Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

17 files changed, 6587 insertions, 0 deletions

diff --git a/fs/hpfs/Kconfig b/fs/hpfs/Kconfig
new file mode 100644
index 0000000000..ac1e9318e6
--- /dev/null
+++ b/fs/hpfs/Kconfig
@@ -0,0 +1,17 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config HPFS_FS
+	tristate "OS/2 HPFS file system support"
+	depends on BLOCK
+	select BUFFER_HEAD
+	select FS_IOMAP
+	help
+	  OS/2 is IBM's operating system for PC's, the same as Warp, and HPFS
+	  is the file system used for organizing files on OS/2 hard disk
+	  partitions. Say Y if you want to be able to read files from and
+	  write files to an OS/2 HPFS partition on your hard drive. OS/2
+	  floppies however are in regular MSDOS format, so you don't need this
+	  option in order to be able to read them. Read
+	  <file:Documentation/filesystems/hpfs.rst>.
+
+	  To compile this file system support as a module, choose M here: the
+	  module will be called hpfs.  If unsure, say N.
diff --git a/fs/hpfs/Makefile b/fs/hpfs/Makefile
new file mode 100644
index 0000000000..153c17382c
--- /dev/null
+++ b/fs/hpfs/Makefile
@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for the Linux hpfs filesystem routines.
+#
+
+obj-$(CONFIG_HPFS_FS) += hpfs.o
+
+hpfs-objs := alloc.o anode.o buffer.o dentry.o dir.o dnode.o ea.o file.o \
+	     inode.o map.o name.o namei.o super.o
diff --git a/fs/hpfs/alloc.c b/fs/hpfs/alloc.c
new file mode 100644
index 0000000000..66617b1557
--- /dev/null
+++ b/fs/hpfs/alloc.c
@@ -0,0 +1,582 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/hpfs/alloc.c
+ *
+ *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
+ *
+ *  HPFS bitmap operations
+ */
+
+#include "hpfs_fn.h"
+
+static void hpfs_claim_alloc(struct super_block *s, secno sec)
+{
+	struct hpfs_sb_info *sbi = hpfs_sb(s);
+	if (sbi->sb_n_free != (unsigned)-1) {
+		if (unlikely(!sbi->sb_n_free)) {
+			hpfs_error(s, "free count underflow, allocating sector %08x", sec);
+			sbi->sb_n_free = -1;
+			return;
+		}
+		sbi->sb_n_free--;
+	}
+}
+
+static void hpfs_claim_free(struct super_block *s, secno sec)
+{
+	struct hpfs_sb_info *sbi = hpfs_sb(s);
+	if (sbi->sb_n_free != (unsigned)-1) {
+		if (unlikely(sbi->sb_n_free >= sbi->sb_fs_size)) {
+			hpfs_error(s, "free count overflow, freeing sector %08x", sec);
+			sbi->sb_n_free = -1;
+			return;
+		}
+		sbi->sb_n_free++;
+	}
+}
+
+static void hpfs_claim_dirband_alloc(struct super_block *s, secno sec)
+{
+	struct hpfs_sb_info *sbi = hpfs_sb(s);
+	if (sbi->sb_n_free_dnodes != (unsigned)-1) {
+		if (unlikely(!sbi->sb_n_free_dnodes)) {
+			hpfs_error(s, "dirband free count underflow, allocating sector %08x", sec);
+			sbi->sb_n_free_dnodes = -1;
+			return;
+		}
+		sbi->sb_n_free_dnodes--;
+	}
+}
+
+static void hpfs_claim_dirband_free(struct super_block *s, secno sec)
+{
+	struct hpfs_sb_info *sbi = hpfs_sb(s);
+	if (sbi->sb_n_free_dnodes != (unsigned)-1) {
+		if (unlikely(sbi->sb_n_free_dnodes >= sbi->sb_dirband_size / 4)) {
+			hpfs_error(s, "dirband free count overflow, freeing sector %08x", sec);
+			sbi->sb_n_free_dnodes = -1;
+			return;
+		}
+		sbi->sb_n_free_dnodes++;
+	}
+}
+
+/*
+ * Check if a sector is allocated in bitmap
+ * This is really slow. Turned on only if chk==2
+ */
+
+static int chk_if_allocated(struct super_block *s, secno sec, char *msg)
+{
+	struct quad_buffer_head qbh;
+	__le32 *bmp;
+	if (!(bmp = hpfs_map_bitmap(s, sec >> 14, &qbh, "chk"))) goto fail;
+	if ((le32_to_cpu(bmp[(sec & 0x3fff) >> 5]) >> (sec & 0x1f)) & 1) {
+		hpfs_error(s, "sector '%s' - %08x not allocated in bitmap", msg, sec);
+		goto fail1;
+	}
+	hpfs_brelse4(&qbh);
+	if (sec >= hpfs_sb(s)->sb_dirband_start && sec < hpfs_sb(s)->sb_dirband_start + hpfs_sb(s)->sb_dirband_size) {
+		unsigned ssec = (sec - hpfs_sb(s)->sb_dirband_start) / 4;
+		if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) goto fail;
+		if ((le32_to_cpu(bmp[ssec >> 5]) >> (ssec & 0x1f)) & 1) {
+			hpfs_error(s, "sector '%s' - %08x not allocated in directory bitmap", msg, sec);
+			goto fail1;
+		}
+		hpfs_brelse4(&qbh);
+	}
+	return 0;
+	fail1:
+	hpfs_brelse4(&qbh);
+	fail:
+	return 1;
+}
+
+/*
+ * Check if sector(s) have proper number and additionally check if they're
+ * allocated in bitmap.
+ */
+	
+int hpfs_chk_sectors(struct super_block *s, secno start, int len, char *msg)
+{
+	if (start + len < start || start < 0x12 ||
+	    start + len > hpfs_sb(s)->sb_fs_size) {
+	    	hpfs_error(s, "sector(s) '%s' badly placed at %08x", msg, start);
+		return 1;
+	}
+	if (hpfs_sb(s)->sb_chk>=2) {
+		int i;
+		for (i = 0; i < len; i++)
+			if (chk_if_allocated(s, start + i, msg)) return 1;
+	}
+	return 0;
+}
+
+static secno alloc_in_bmp(struct super_block *s, secno near, unsigned n, unsigned forward)
+{
+	struct quad_buffer_head qbh;
+	__le32 *bmp;
+	unsigned bs = near & ~0x3fff;
+	unsigned nr = (near & 0x3fff) & ~(n - 1);
+	/*unsigned mnr;*/
+	unsigned i, q;
+	int a, b;
+	secno ret = 0;
+	if (n != 1 && n != 4) {
+		hpfs_error(s, "Bad allocation size: %d", n);
+		return 0;
+	}
+	if (bs != ~0x3fff) {
+		if (!(bmp = hpfs_map_bitmap(s, near >> 14, &qbh, "aib"))) goto uls;
+	} else {
+		if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) goto uls;
+	}
+	if (!tstbits(bmp, nr, n + forward)) {
+		ret = bs + nr;
+		goto rt;
+	}
+	q = nr + n; b = 0;
+	while ((a = tstbits(bmp, q, n + forward)) != 0) {
+		q += a;
+		if (n != 1) q = ((q-1)&~(n-1))+n;
+		if (!b) {
+			if (q>>5 != nr>>5) {
+				b = 1;
+				q = nr & 0x1f;
+			}
+		} else if (q > nr) break;
+	}
+	if (!a) {
+		ret = bs + q;
+		goto rt;
+	}
+	nr >>= 5;
+	/*for (i = nr + 1; i != nr; i++, i &= 0x1ff) */
+	i = nr;
+	do {
+		if (!le32_to_cpu(bmp[i])) goto cont;
+		if (n + forward >= 0x3f && le32_to_cpu(bmp[i]) != 0xffffffff) goto cont;
+		q = i<<5;
+		if (i > 0) {
+			unsigned k = le32_to_cpu(bmp[i-1]);
+			while (k & 0x80000000) {
+				q--; k <<= 1;
+			}
+		}
+		if (n != 1) q = ((q-1)&~(n-1))+n;
+		while ((a = tstbits(bmp, q, n + forward)) != 0) {
+			q += a;
+			if (n != 1) q = ((q-1)&~(n-1))+n;
+			if (q>>5 > i) break;
+		}
+		if (!a) {
+			ret = bs + q;
+			goto rt;
+		}
+		cont:
+		i++, i &= 0x1ff;
+	} while (i != nr);
+	rt:
+	if (ret) {
+		if (hpfs_sb(s)->sb_chk && ((ret >> 14) != (bs >> 14) || (le32_to_cpu(bmp[(ret & 0x3fff) >> 5]) | ~(((1 << n) - 1) << (ret & 0x1f))) != 0xffffffff)) {
+			hpfs_error(s, "Allocation doesn't work! Wanted %d, allocated at %08x", n, ret);
+			ret = 0;
+			goto b;
+		}
+		bmp[(ret & 0x3fff) >> 5] &= cpu_to_le32(~(((1 << n) - 1) << (ret & 0x1f)));
+		hpfs_mark_4buffers_dirty(&qbh);
+	}
+	b:
+	hpfs_brelse4(&qbh);
+	uls:
+	return ret;
+}
+
+/*
+ * Allocation strategy:	1) search place near the sector specified
+ *			2) search bitmap where free sectors last found
+ *			3) search all bitmaps
+ *			4) search all bitmaps ignoring number of pre-allocated
+ *				sectors
+ */
+
+secno hpfs_alloc_sector(struct super_block *s, secno near, unsigned n, int forward)
+{
+	secno sec;
+	int i;
+	unsigned n_bmps;
+	struct hpfs_sb_info *sbi = hpfs_sb(s);
+	int f_p = 0;
+	int near_bmp;
+	if (forward < 0) {
+		forward = -forward;
+		f_p = 1;
+	}
+	n_bmps = (sbi->sb_fs_size + 0x4000 - 1) >> 14;
+	if (near && near < sbi->sb_fs_size) {
+		if ((sec = alloc_in_bmp(s, near, n, f_p ? forward : forward/4))) goto ret;
+		near_bmp = near >> 14;
+	} else near_bmp = n_bmps / 2;
+	/*
+	if (b != -1) {
+		if ((sec = alloc_in_bmp(s, b<<14, n, f_p ? forward : forward/2))) {
+			b &= 0x0fffffff;
+			goto ret;
+		}
+		if (b > 0x10000000) if ((sec = alloc_in_bmp(s, (b&0xfffffff)<<14, n, f_p ? forward : 0))) goto ret;
+	*/
+	if (!f_p) if (forward > sbi->sb_max_fwd_alloc) forward = sbi->sb_max_fwd_alloc;
+	less_fwd:
+	for (i = 0; i < n_bmps; i++) {
+		if (near_bmp+i < n_bmps && ((sec = alloc_in_bmp(s, (near_bmp+i) << 14, n, forward)))) {
+			sbi->sb_c_bitmap = near_bmp+i;
+			goto ret;
+		}	
+		if (!forward) {
+			if (near_bmp-i-1 >= 0 && ((sec = alloc_in_bmp(s, (near_bmp-i-1) << 14, n, forward)))) {
+				sbi->sb_c_bitmap = near_bmp-i-1;
+				goto ret;
+			}
+		} else {
+			if (near_bmp+i >= n_bmps && ((sec = alloc_in_bmp(s, (near_bmp+i-n_bmps) << 14, n, forward)))) {
+				sbi->sb_c_bitmap = near_bmp+i-n_bmps;
+				goto ret;
+			}
+		}
+		if (i == 1 && sbi->sb_c_bitmap != -1 && ((sec = alloc_in_bmp(s, (sbi->sb_c_bitmap) << 14, n, forward)))) {
+			goto ret;
+		}
+	}
+	if (!f_p) {
+		if (forward) {
+			sbi->sb_max_fwd_alloc = forward * 3 / 4;
+			forward /= 2;
+			goto less_fwd;
+		}
+	}
+	sec = 0;
+	ret:
+	if (sec) {
+		i = 0;
+		do
+			hpfs_claim_alloc(s, sec + i);
+		while (unlikely(++i < n));
+	}
+	if (sec && f_p) {
+		for (i = 0; i < forward; i++) {
+			if (!hpfs_alloc_if_possible(s, sec + n + i)) {
+				hpfs_error(s, "Prealloc doesn't work! Wanted %d, allocated at %08x, can't allocate %d", forward, sec, i);
+				sec = 0;
+				break;
+			}
+		}
+	}
+	return sec;
+}
+
+static secno alloc_in_dirband(struct super_block *s, secno near)
+{
+	unsigned nr = near;
+	secno sec;
+	struct hpfs_sb_info *sbi = hpfs_sb(s);
+	if (nr < sbi->sb_dirband_start)
+		nr = sbi->sb_dirband_start;
+	if (nr >= sbi->sb_dirband_start + sbi->sb_dirband_size)
+		nr = sbi->sb_dirband_start + sbi->sb_dirband_size - 4;
+	nr -= sbi->sb_dirband_start;
+	nr >>= 2;
+	sec = alloc_in_bmp(s, (~0x3fff) | nr, 1, 0);
+	if (!sec) return 0;
+	hpfs_claim_dirband_alloc(s, sec);
+	return ((sec & 0x3fff) << 2) + sbi->sb_dirband_start;
+}
+
+/* Alloc sector if it's free */
+
+int hpfs_alloc_if_possible(struct super_block *s, secno sec)
+{
+	struct quad_buffer_head qbh;
+	__le32 *bmp;
+	if (!(bmp = hpfs_map_bitmap(s, sec >> 14, &qbh, "aip"))) goto end;
+	if (le32_to_cpu(bmp[(sec & 0x3fff) >> 5]) & (1 << (sec & 0x1f))) {
+		bmp[(sec & 0x3fff) >> 5] &= cpu_to_le32(~(1 << (sec & 0x1f)));
+		hpfs_mark_4buffers_dirty(&qbh);
+		hpfs_brelse4(&qbh);
+		hpfs_claim_alloc(s, sec);
+		return 1;
+	}
+	hpfs_brelse4(&qbh);
+	end:
+	return 0;
+}
+
+/* Free sectors in bitmaps */
+
+void hpfs_free_sectors(struct super_block *s, secno sec, unsigned n)
+{
+	struct quad_buffer_head qbh;
+	__le32 *bmp;
+	struct hpfs_sb_info *sbi = hpfs_sb(s);
+	/*pr_info("2 - ");*/
+	if (!n) return;
+	if (sec < 0x12) {
+		hpfs_error(s, "Trying to free reserved sector %08x", sec);
+		return;
+	}
+	sbi->sb_max_fwd_alloc += n > 0xffff ? 0xffff : n;
+	if (sbi->sb_max_fwd_alloc > 0xffffff) sbi->sb_max_fwd_alloc = 0xffffff;
+	new_map:
+	if (!(bmp = hpfs_map_bitmap(s, sec >> 14, &qbh, "free"))) {
+		return;
+	}	
+	new_tst:
+	if ((le32_to_cpu(bmp[(sec & 0x3fff) >> 5]) >> (sec & 0x1f) & 1)) {
+		hpfs_error(s, "sector %08x not allocated", sec);
+		hpfs_brelse4(&qbh);
+		return;
+	}
+	bmp[(sec & 0x3fff) >> 5] |= cpu_to_le32(1 << (sec & 0x1f));
+	hpfs_claim_free(s, sec);
+	if (!--n) {
+		hpfs_mark_4buffers_dirty(&qbh);
+		hpfs_brelse4(&qbh);
+		return;
+	}	
+	if (!(++sec & 0x3fff)) {
+		hpfs_mark_4buffers_dirty(&qbh);
+		hpfs_brelse4(&qbh);
+		goto new_map;
+	}
+	goto new_tst;
+}
+
+/*
+ * Check if there are at least n free dnodes on the filesystem.
+ * Called before adding to dnode. If we run out of space while
+ * splitting dnodes, it would corrupt dnode tree.
+ */
+
+int hpfs_check_free_dnodes(struct super_block *s, int n)
+{
+	int n_bmps = (hpfs_sb(s)->sb_fs_size + 0x4000 - 1) >> 14;
+	int b = hpfs_sb(s)->sb_c_bitmap & 0x0fffffff;
+	int i, j;
+	__le32 *bmp;
+	struct quad_buffer_head qbh;
+	if ((bmp = hpfs_map_dnode_bitmap(s, &qbh))) {
+		for (j = 0; j < 512; j++) {
+			unsigned k;
+			if (!le32_to_cpu(bmp[j])) continue;
+			for (k = le32_to_cpu(bmp[j]); k; k >>= 1) if (k & 1) if (!--n) {
+				hpfs_brelse4(&qbh);
+				return 0;
+			}
+		}
+	}
+	hpfs_brelse4(&qbh);
+	i = 0;
+	if (hpfs_sb(s)->sb_c_bitmap != -1) {
+		bmp = hpfs_map_bitmap(s, b, &qbh, "chkdn1");
+		goto chk_bmp;
+	}
+	chk_next:
+	if (i == b) i++;
+	if (i >= n_bmps) return 1;
+	bmp = hpfs_map_bitmap(s, i, &qbh, "chkdn2");
+	chk_bmp:
+	if (bmp) {
+		for (j = 0; j < 512; j++) {
+			u32 k;
+			if (!le32_to_cpu(bmp[j])) continue;
+			for (k = 0xf; k; k <<= 4)
+				if ((le32_to_cpu(bmp[j]) & k) == k) {
+					if (!--n) {
+						hpfs_brelse4(&qbh);
+						return 0;
+					}
+				}
+		}
+		hpfs_brelse4(&qbh);
+	}
+	i++;
+	goto chk_next;
+}
+
+void hpfs_free_dnode(struct super_block *s, dnode_secno dno)
+{
+	if (hpfs_sb(s)->sb_chk) if (dno & 3) {
+		hpfs_error(s, "hpfs_free_dnode: dnode %08x not aligned", dno);
+		return;
+	}
+	if (dno < hpfs_sb(s)->sb_dirband_start ||
+	    dno >= hpfs_sb(s)->sb_dirband_start + hpfs_sb(s)->sb_dirband_size) {
+		hpfs_free_sectors(s, dno, 4);
+	} else {
+		struct quad_buffer_head qbh;
+		__le32 *bmp;
+		unsigned ssec = (dno - hpfs_sb(s)->sb_dirband_start) / 4;
+		if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) {
+			return;
+		}
+		bmp[ssec >> 5] |= cpu_to_le32(1 << (ssec & 0x1f));
+		hpfs_mark_4buffers_dirty(&qbh);
+		hpfs_brelse4(&qbh);
+		hpfs_claim_dirband_free(s, dno);
+	}
+}
+
+struct dnode *hpfs_alloc_dnode(struct super_block *s, secno near,
+			 dnode_secno *dno, struct quad_buffer_head *qbh)
+{
+	struct dnode *d;
+	if (hpfs_get_free_dnodes(s) > FREE_DNODES_ADD) {
+		if (!(*dno = alloc_in_dirband(s, near)))
+			if (!(*dno = hpfs_alloc_sector(s, near, 4, 0))) return NULL;
+	} else {
+		if (!(*dno = hpfs_alloc_sector(s, near, 4, 0)))
+			if (!(*dno = alloc_in_dirband(s, near))) return NULL;
+	}
+	if (!(d = hpfs_get_4sectors(s, *dno, qbh))) {
+		hpfs_free_dnode(s, *dno);
+		return NULL;
+	}
+	memset(d, 0, 2048);
+	d->magic = cpu_to_le32(DNODE_MAGIC);
+	d->first_free = cpu_to_le32(52);
+	d->dirent[0] = 32;
+	d->dirent[2] = 8;
+	d->dirent[30] = 1;
+	d->dirent[31] = 255;
+	d->self = cpu_to_le32(*dno);
+	return d;
+}
+
+struct fnode *hpfs_alloc_fnode(struct super_block *s, secno near, fnode_secno *fno,
+			  struct buffer_head **bh)
+{
+	struct fnode *f;
+	if (!(*fno = hpfs_alloc_sector(s, near, 1, FNODE_ALLOC_FWD))) return NULL;
+	if (!(f = hpfs_get_sector(s, *fno, bh))) {
+		hpfs_free_sectors(s, *fno, 1);
+		return NULL;
+	}	
+	memset(f, 0, 512);
+	f->magic = cpu_to_le32(FNODE_MAGIC);
+	f->ea_offs = cpu_to_le16(0xc4);
+	f->btree.n_free_nodes = 8;
+	f->btree.first_free = cpu_to_le16(8);
+	return f;
+}
+
+struct anode *hpfs_alloc_anode(struct super_block *s, secno near, anode_secno *ano,
+			  struct buffer_head **bh)
+{
+	struct anode *a;
+	if (!(*ano = hpfs_alloc_sector(s, near, 1, ANODE_ALLOC_FWD))) return NULL;
+	if (!(a = hpfs_get_sector(s, *ano, bh))) {
+		hpfs_free_sectors(s, *ano, 1);
+		return NULL;
+	}
+	memset(a, 0, 512);
+	a->magic = cpu_to_le32(ANODE_MAGIC);
+	a->self = cpu_to_le32(*ano);
+	a->btree.n_free_nodes = 40;
+	a->btree.n_used_nodes = 0;
+	a->btree.first_free = cpu_to_le16(8);
+	return a;
+}
+
+static unsigned find_run(__le32 *bmp, unsigned *idx)
+{
+	unsigned len;
+	while (tstbits(bmp, *idx, 1)) {
+		(*idx)++;
+		if (unlikely(*idx >= 0x4000))
+			return 0;
+	}
+	len = 1;
+	while (!tstbits(bmp, *idx + len, 1))
+		len++;
+	return len;
+}
+
+static int do_trim(struct super_block *s, secno start, unsigned len, secno limit_start, secno limit_end, unsigned minlen, unsigned *result)
+{
+	int err;
+	secno end;
+	if (fatal_signal_pending(current))
+		return -EINTR;
+	end = start + len;
+	if (start < limit_start)
+		start = limit_start;
+	if (end > limit_end)
+		end = limit_end;
+	if (start >= end)
+		return 0;
+	if (end - start < minlen)
+		return 0;
+	err = sb_issue_discard(s, start, end - start, GFP_NOFS, 0);
+	if (err)
+		return err;
+	*result += end - start;
+	return 0;
+}
+
+int hpfs_trim_fs(struct super_block *s, u64 start, u64 end, u64 minlen, unsigned *result)
+{
+	int err = 0;
+	struct hpfs_sb_info *sbi = hpfs_sb(s);
+	unsigned idx, len, start_bmp, end_bmp;
+	__le32 *bmp;
+	struct quad_buffer_head qbh;
+
+	*result = 0;
+	if (!end || end > sbi->sb_fs_size)
+		end = sbi->sb_fs_size;
+	if (start >= sbi->sb_fs_size)
+		return 0;
+	if (minlen > 0x4000)
+		return 0;
+	if (start < sbi->sb_dirband_start + sbi->sb_dirband_size && end > sbi->sb_dirband_start) {
+		hpfs_lock(s);
+		if (sb_rdonly(s)) {
+			err = -EROFS;
+			goto unlock_1;
+		}
+		if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) {
+			err = -EIO;
+			goto unlock_1;
+		}
+		idx = 0;
+		while ((len = find_run(bmp, &idx)) && !err) {
+			err = do_trim(s, sbi->sb_dirband_start + idx * 4, len * 4, start, end, minlen, result);
+			idx += len;
+		}
+		hpfs_brelse4(&qbh);
+unlock_1:
+		hpfs_unlock(s);
+	}
+	start_bmp = start >> 14;
+	end_bmp = (end + 0x3fff) >> 14;
+	while (start_bmp < end_bmp && !err) {
+		hpfs_lock(s);
+		if (sb_rdonly(s)) {
+			err = -EROFS;
+			goto unlock_2;
+		}
+		if (!(bmp = hpfs_map_bitmap(s, start_bmp, &qbh, "trim"))) {
+			err = -EIO;
+			goto unlock_2;
+		}
+		idx = 0;
+		while ((len = find_run(bmp, &idx)) && !err) {
+			err = do_trim(s, (start_bmp << 14) + idx, len, start, end, minlen, result);
+			idx += len;
+		}
+		hpfs_brelse4(&qbh);
+unlock_2:
+		hpfs_unlock(s);
+		start_bmp++;
+	}
+	return err;
+}
diff --git a/fs/hpfs/anode.c b/fs/hpfs/anode.c
new file mode 100644
index 0000000000..c14c9a035e
--- /dev/null
+++ b/fs/hpfs/anode.c
@@ -0,0 +1,497 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/hpfs/anode.c
+ *
+ *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
+ *
+ *  handling HPFS anode tree that contains file allocation info
+ */
+
+#include "hpfs_fn.h"
+
+/* Find a sector in allocation tree */
+
+secno hpfs_bplus_lookup(struct super_block *s, struct inode *inode,
+		   struct bplus_header *btree, unsigned sec,
+		   struct buffer_head *bh)
+{
+	anode_secno a = -1;
+	struct anode *anode;
+	int i;
+	int c1, c2 = 0;
+	go_down:
+	if (hpfs_sb(s)->sb_chk) if (hpfs_stop_cycles(s, a, &c1, &c2, "hpfs_bplus_lookup")) return -1;
+	if (bp_internal(btree)) {
+		for (i = 0; i < btree->n_used_nodes; i++)
+			if (le32_to_cpu(btree->u.internal[i].file_secno) > sec) {
+				a = le32_to_cpu(btree->u.internal[i].down);
+				brelse(bh);
+				if (!(anode = hpfs_map_anode(s, a, &bh))) return -1;
+				btree = &anode->btree;
+				goto go_down;
+			}
+		hpfs_error(s, "sector %08x not found in internal anode %08x", sec, a);
+		brelse(bh);
+		return -1;
+	}
+	for (i = 0; i < btree->n_used_nodes; i++)
+		if (le32_to_cpu(btree->u.external[i].file_secno) <= sec &&
+		    le32_to_cpu(btree->u.external[i].file_secno) + le32_to_cpu(btree->u.external[i].length) > sec) {
+			a = le32_to_cpu(btree->u.external[i].disk_secno) + sec - le32_to_cpu(btree->u.external[i].file_secno);
+			if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, a, 1, "data")) {
+				brelse(bh);
+				return -1;
+			}
+			if (inode) {
+				struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
+				hpfs_inode->i_file_sec = le32_to_cpu(btree->u.external[i].file_secno);
+				hpfs_inode->i_disk_sec = le32_to_cpu(btree->u.external[i].disk_secno);
+				hpfs_inode->i_n_secs = le32_to_cpu(btree->u.external[i].length);
+			}
+			brelse(bh);
+			return a;
+		}
+	hpfs_error(s, "sector %08x not found in external anode %08x", sec, a);
+	brelse(bh);
+	return -1;
+}
+
+/* Add a sector to tree */
+
+secno hpfs_add_sector_to_btree(struct super_block *s, secno node, int fnod, unsigned fsecno)
+{
+	struct bplus_header *btree;
+	struct anode *anode = NULL, *ranode = NULL;
+	struct fnode *fnode;
+	anode_secno a, na = -1, ra, up = -1;
+	secno se;
+	struct buffer_head *bh, *bh1, *bh2;
+	int n;
+	unsigned fs;
+	int c1, c2 = 0;
+	if (fnod) {
+		if (!(fnode = hpfs_map_fnode(s, node, &bh))) return -1;
+		btree = &fnode->btree;
+	} else {
+		if (!(anode = hpfs_map_anode(s, node, &bh))) return -1;
+		btree = &anode->btree;
+	}
+	a = node;
+	go_down:
+	if ((n = btree->n_used_nodes - 1) < -!!fnod) {
+		hpfs_error(s, "anode %08x has no entries", a);
+		brelse(bh);
+		return -1;
+	}
+	if (bp_internal(btree)) {
+		a = le32_to_cpu(btree->u.internal[n].down);
+		btree->u.internal[n].file_secno = cpu_to_le32(-1);
+		mark_buffer_dirty(bh);
+		brelse(bh);
+		if (hpfs_sb(s)->sb_chk)
+			if (hpfs_stop_cycles(s, a, &c1, &c2, "hpfs_add_sector_to_btree #1")) return -1;
+		if (!(anode = hpfs_map_anode(s, a, &bh))) return -1;
+		btree = &anode->btree;
+		goto go_down;
+	}
+	if (n >= 0) {
+		if (le32_to_cpu(btree->u.external[n].file_secno) + le32_to_cpu(btree->u.external[n].length) != fsecno) {
+			hpfs_error(s, "allocated size %08x, trying to add sector %08x, %cnode %08x",
+				le32_to_cpu(btree->u.external[n].file_secno) + le32_to_cpu(btree->u.external[n].length), fsecno,
+				fnod?'f':'a', node);
+			brelse(bh);
+			return -1;
+		}
+		if (hpfs_alloc_if_possible(s, se = le32_to_cpu(btree->u.external[n].disk_secno) + le32_to_cpu(btree->u.external[n].length))) {
+			le32_add_cpu(&btree->u.external[n].length, 1);
+			mark_buffer_dirty(bh);
+			brelse(bh);
+			return se;
+		}
+	} else {
+		if (fsecno) {
+			hpfs_error(s, "empty file %08x, trying to add sector %08x", node, fsecno);
+			brelse(bh);
+			return -1;
+		}
+		se = !fnod ? node : (node + 16384) & ~16383;
+	}	
+	if (!(se = hpfs_alloc_sector(s, se, 1, fsecno*ALLOC_M>ALLOC_FWD_MAX ? ALLOC_FWD_MAX : fsecno*ALLOC_M<ALLOC_FWD_MIN ? ALLOC_FWD_MIN : fsecno*ALLOC_M))) {
+		brelse(bh);
+		return -1;
+	}
+	fs = n < 0 ? 0 : le32_to_cpu(btree->u.external[n].file_secno) + le32_to_cpu(btree->u.external[n].length);
+	if (!btree->n_free_nodes) {
+		up = a != node ? le32_to_cpu(anode->up) : -1;
+		if (!(anode = hpfs_alloc_anode(s, a, &na, &bh1))) {
+			brelse(bh);
+			hpfs_free_sectors(s, se, 1);
+			return -1;
+		}
+		if (a == node && fnod) {
+			anode->up = cpu_to_le32(node);
+			anode->btree.flags |= BP_fnode_parent;
+			anode->btree.n_used_nodes = btree->n_used_nodes;
+			anode->btree.first_free = btree->first_free;
+			anode->btree.n_free_nodes = 40 - anode->btree.n_used_nodes;
+			memcpy(&anode->u, &btree->u, btree->n_used_nodes * 12);
+			btree->flags |= BP_internal;
+			btree->n_free_nodes = 11;
+			btree->n_used_nodes = 1;
+			btree->first_free = cpu_to_le16((char *)&(btree->u.internal[1]) - (char *)btree);
+			btree->u.internal[0].file_secno = cpu_to_le32(-1);
+			btree->u.internal[0].down = cpu_to_le32(na);
+			mark_buffer_dirty(bh);
+		} else if (!(ranode = hpfs_alloc_anode(s, /*a*/0, &ra, &bh2))) {
+			brelse(bh);
+			brelse(bh1);
+			hpfs_free_sectors(s, se, 1);
+			hpfs_free_sectors(s, na, 1);
+			return -1;
+		}
+		brelse(bh);
+		bh = bh1;
+		btree = &anode->btree;
+	}
+	btree->n_free_nodes--; n = btree->n_used_nodes++;
+	le16_add_cpu(&btree->first_free, 12);
+	btree->u.external[n].disk_secno = cpu_to_le32(se);
+	btree->u.external[n].file_secno = cpu_to_le32(fs);
+	btree->u.external[n].length = cpu_to_le32(1);
+	mark_buffer_dirty(bh);
+	brelse(bh);
+	if ((a == node && fnod) || na == -1) return se;
+	c2 = 0;
+	while (up != (anode_secno)-1) {
+		struct anode *new_anode;
+		if (hpfs_sb(s)->sb_chk)
+			if (hpfs_stop_cycles(s, up, &c1, &c2, "hpfs_add_sector_to_btree #2")) return -1;
+		if (up != node || !fnod) {
+			if (!(anode = hpfs_map_anode(s, up, &bh))) return -1;
+			btree = &anode->btree;
+		} else {
+			if (!(fnode = hpfs_map_fnode(s, up, &bh))) return -1;
+			btree = &fnode->btree;
+		}
+		if (btree->n_free_nodes) {
+			btree->n_free_nodes--; n = btree->n_used_nodes++;
+			le16_add_cpu(&btree->first_free, 8);
+			btree->u.internal[n].file_secno = cpu_to_le32(-1);
+			btree->u.internal[n].down = cpu_to_le32(na);
+			btree->u.internal[n-1].file_secno = cpu_to_le32(fs);
+			mark_buffer_dirty(bh);
+			brelse(bh);
+			brelse(bh2);
+			hpfs_free_sectors(s, ra, 1);
+			if ((anode = hpfs_map_anode(s, na, &bh))) {
+				anode->up = cpu_to_le32(up);
+				if (up == node && fnod)
+					anode->btree.flags |= BP_fnode_parent;
+				else
+					anode->btree.flags &= ~BP_fnode_parent;
+				mark_buffer_dirty(bh);
+				brelse(bh);
+			}
+			return se;
+		}
+		up = up != node ? le32_to_cpu(anode->up) : -1;
+		btree->u.internal[btree->n_used_nodes - 1].file_secno = cpu_to_le32(/*fs*/-1);
+		mark_buffer_dirty(bh);
+		brelse(bh);
+		a = na;
+		if ((new_anode = hpfs_alloc_anode(s, a, &na, &bh))) {
+			anode = new_anode;
+			/*anode->up = cpu_to_le32(up != -1 ? up : ra);*/
+			anode->btree.flags |= BP_internal;
+			anode->btree.n_used_nodes = 1;
+			anode->btree.n_free_nodes = 59;
+			anode->btree.first_free = cpu_to_le16(16);
+			anode->btree.u.internal[0].down = cpu_to_le32(a);
+			anode->btree.u.internal[0].file_secno = cpu_to_le32(-1);
+			mark_buffer_dirty(bh);
+			brelse(bh);
+			if ((anode = hpfs_map_anode(s, a, &bh))) {
+				anode->up = cpu_to_le32(na);
+				mark_buffer_dirty(bh);
+				brelse(bh);
+			}
+		} else na = a;
+	}
+	if ((anode = hpfs_map_anode(s, na, &bh))) {
+		anode->up = cpu_to_le32(node);
+		if (fnod)
+			anode->btree.flags |= BP_fnode_parent;
+		mark_buffer_dirty(bh);
+		brelse(bh);
+	}
+	if (!fnod) {
+		if (!(anode = hpfs_map_anode(s, node, &bh))) {
+			brelse(bh2);
+			return -1;
+		}
+		btree = &anode->btree;
+	} else {
+		if (!(fnode = hpfs_map_fnode(s, node, &bh))) {
+			brelse(bh2);
+			return -1;
+		}
+		btree = &fnode->btree;
+	}
+	ranode->up = cpu_to_le32(node);
+	memcpy(&ranode->btree, btree, le16_to_cpu(btree->first_free));
+	if (fnod)
+		ranode->btree.flags |= BP_fnode_parent;
+	ranode->btree.n_free_nodes = (bp_internal(&ranode->btree) ? 60 : 40) - ranode->btree.n_used_nodes;
+	if (bp_internal(&ranode->btree)) for (n = 0; n < ranode->btree.n_used_nodes; n++) {
+		struct anode *unode;
+		if ((unode = hpfs_map_anode(s, le32_to_cpu(ranode->u.internal[n].down), &bh1))) {
+			unode->up = cpu_to_le32(ra);
+			unode->btree.flags &= ~BP_fnode_parent;
+			mark_buffer_dirty(bh1);
+			brelse(bh1);
+		}
+	}
+	btree->flags |= BP_internal;
+	btree->n_free_nodes = fnod ? 10 : 58;
+	btree->n_used_nodes = 2;
+	btree->first_free = cpu_to_le16((char *)&btree->u.internal[2] - (char *)btree);
+	btree->u.internal[0].file_secno = cpu_to_le32(fs);
+	btree->u.internal[0].down = cpu_to_le32(ra);
+	btree->u.internal[1].file_secno = cpu_to_le32(-1);
+	btree->u.internal[1].down = cpu_to_le32(na);
+	mark_buffer_dirty(bh);
+	brelse(bh);
+	mark_buffer_dirty(bh2);
+	brelse(bh2);
+	return se;
+}
+
+/*
+ * Remove allocation tree. Recursion would look much nicer but
+ * I want to avoid it because it can cause stack overflow.
+ */
+
+void hpfs_remove_btree(struct super_block *s, struct bplus_header *btree)
+{
+	struct bplus_header *btree1 = btree;
+	struct anode *anode = NULL;
+	anode_secno ano = 0, oano;
+	struct buffer_head *bh;
+	int level = 0;
+	int pos = 0;
+	int i;
+	int c1, c2 = 0;
+	int d1, d2;
+	go_down:
+	d2 = 0;
+	while (bp_internal(btree1)) {
+		ano = le32_to_cpu(btree1->u.internal[pos].down);
+		if (level) brelse(bh);
+		if (hpfs_sb(s)->sb_chk)
+			if (hpfs_stop_cycles(s, ano, &d1, &d2, "hpfs_remove_btree #1"))
+				return;
+		if (!(anode = hpfs_map_anode(s, ano, &bh))) return;
+		btree1 = &anode->btree;
+		level++;
+		pos = 0;
+	}
+	for (i = 0; i < btree1->n_used_nodes; i++)
+		hpfs_free_sectors(s, le32_to_cpu(btree1->u.external[i].disk_secno), le32_to_cpu(btree1->u.external[i].length));
+	go_up:
+	if (!level) return;
+	brelse(bh);
+	if (hpfs_sb(s)->sb_chk)
+		if (hpfs_stop_cycles(s, ano, &c1, &c2, "hpfs_remove_btree #2")) return;
+	hpfs_free_sectors(s, ano, 1);
+	oano = ano;
+	ano = le32_to_cpu(anode->up);
+	if (--level) {
+		if (!(anode = hpfs_map_anode(s, ano, &bh))) return;
+		btree1 = &anode->btree;
+	} else btree1 = btree;
+	for (i = 0; i < btree1->n_used_nodes; i++) {
+		if (le32_to_cpu(btree1->u.internal[i].down) == oano) {
+			if ((pos = i + 1) < btree1->n_used_nodes)
+				goto go_down;
+			else
+				goto go_up;
+		}
+	}
+	hpfs_error(s,
+		   "reference to anode %08x not found in anode %08x "
+		   "(probably bad up pointer)",
+		   oano, level ? ano : -1);
+	if (level)
+		brelse(bh);
+}
+
+/* Just a wrapper around hpfs_bplus_lookup .. used for reading eas */
+
+static secno anode_lookup(struct super_block *s, anode_secno a, unsigned sec)
+{
+	struct anode *anode;
+	struct buffer_head *bh;
+	if (!(anode = hpfs_map_anode(s, a, &bh))) return -1;
+	return hpfs_bplus_lookup(s, NULL, &anode->btree, sec, bh);
+}
+
+int hpfs_ea_read(struct super_block *s, secno a, int ano, unsigned pos,
+	    unsigned len, char *buf)
+{
+	struct buffer_head *bh;
+	char *data;
+	secno sec;
+	unsigned l;
+	while (len) {
+		if (ano) {
+			if ((sec = anode_lookup(s, a, pos >> 9)) == -1)
+				return -1;
+		} else sec = a + (pos >> 9);
+		if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, sec, 1, "ea #1")) return -1;
+		if (!(data = hpfs_map_sector(s, sec, &bh, (len - 1) >> 9)))
+			return -1;
+		l = 0x200 - (pos & 0x1ff); if (l > len) l = len;
+		memcpy(buf, data + (pos & 0x1ff), l);
+		brelse(bh);
+		buf += l; pos += l; len -= l;
+	}
+	return 0;
+}
+
+int hpfs_ea_write(struct super_block *s, secno a, int ano, unsigned pos,
+	     unsigned len, const char *buf)
+{
+	struct buffer_head *bh;
+	char *data;
+	secno sec;
+	unsigned l;
+	while (len) {
+		if (ano) {
+			if ((sec = anode_lookup(s, a, pos >> 9)) == -1)
+				return -1;
+		} else sec = a + (pos >> 9);
+		if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, sec, 1, "ea #2")) return -1;
+		if (!(data = hpfs_map_sector(s, sec, &bh, (len - 1) >> 9)))
+			return -1;
+		l = 0x200 - (pos & 0x1ff); if (l > len) l = len;
+		memcpy(data + (pos & 0x1ff), buf, l);
+		mark_buffer_dirty(bh);
+		brelse(bh);
+		buf += l; pos += l; len -= l;
+	}
+	return 0;
+}
+
+void hpfs_ea_remove(struct super_block *s, secno a, int ano, unsigned len)
+{
+	struct anode *anode;
+	struct buffer_head *bh;
+	if (ano) {
+		if (!(anode = hpfs_map_anode(s, a, &bh))) return;
+		hpfs_remove_btree(s, &anode->btree);
+		brelse(bh);
+		hpfs_free_sectors(s, a, 1);
+	} else hpfs_free_sectors(s, a, (len + 511) >> 9);
+}
+
+/* Truncate allocation tree. Doesn't join anodes - I hope it doesn't matter */
+
+void hpfs_truncate_btree(struct super_block *s, secno f, int fno, unsigned secs)
+{
+	struct fnode *fnode;
+	struct anode *anode;
+	struct buffer_head *bh;
+	struct bplus_header *btree;
+	anode_secno node = f;
+	int i, j, nodes;
+	int c1, c2 = 0;
+	if (fno) {
+		if (!(fnode = hpfs_map_fnode(s, f, &bh))) return;
+		btree = &fnode->btree;
+	} else {
+		if (!(anode = hpfs_map_anode(s, f, &bh))) return;
+		btree = &anode->btree;
+	}
+	if (!secs) {
+		hpfs_remove_btree(s, btree);
+		if (fno) {
+			btree->n_free_nodes = 8;
+			btree->n_used_nodes = 0;
+			btree->first_free = cpu_to_le16(8);
+			btree->flags &= ~BP_internal;
+			mark_buffer_dirty(bh);
+		} else hpfs_free_sectors(s, f, 1);
+		brelse(bh);
+		return;
+	}
+	while (bp_internal(btree)) {
+		nodes = btree->n_used_nodes + btree->n_free_nodes;
+		for (i = 0; i < btree->n_used_nodes; i++)
+			if (le32_to_cpu(btree->u.internal[i].file_secno) >= secs) goto f;
+		brelse(bh);
+		hpfs_error(s, "internal btree %08x doesn't end with -1", node);
+		return;
+		f:
+		for (j = i + 1; j < btree->n_used_nodes; j++)
+			hpfs_ea_remove(s, le32_to_cpu(btree->u.internal[j].down), 1, 0);
+		btree->n_used_nodes = i + 1;
+		btree->n_free_nodes = nodes - btree->n_used_nodes;
+		btree->first_free = cpu_to_le16(8 + 8 * btree->n_used_nodes);
+		mark_buffer_dirty(bh);
+		if (btree->u.internal[i].file_secno == cpu_to_le32(secs)) {
+			brelse(bh);
+			return;
+		}
+		node = le32_to_cpu(btree->u.internal[i].down);
+		brelse(bh);
+		if (hpfs_sb(s)->sb_chk)
+			if (hpfs_stop_cycles(s, node, &c1, &c2, "hpfs_truncate_btree"))
+				return;
+		if (!(anode = hpfs_map_anode(s, node, &bh))) return;
+		btree = &anode->btree;
+	}	
+	nodes = btree->n_used_nodes + btree->n_free_nodes;
+	for (i = 0; i < btree->n_used_nodes; i++)
+		if (le32_to_cpu(btree->u.external[i].file_secno) + le32_to_cpu(btree->u.external[i].length) >= secs) goto ff;
+	brelse(bh);
+	return;
+	ff:
+	if (secs <= le32_to_cpu(btree->u.external[i].file_secno)) {
+		hpfs_error(s, "there is an allocation error in file %08x, sector %08x", f, secs);
+		if (i) i--;
+	}
+	else if (le32_to_cpu(btree->u.external[i].file_secno) + le32_to_cpu(btree->u.external[i].length) > secs) {
+		hpfs_free_sectors(s, le32_to_cpu(btree->u.external[i].disk_secno) + secs -
+			le32_to_cpu(btree->u.external[i].file_secno), le32_to_cpu(btree->u.external[i].length)
+			- secs + le32_to_cpu(btree->u.external[i].file_secno)); /* I hope gcc optimizes this :-) */
+		btree->u.external[i].length = cpu_to_le32(secs - le32_to_cpu(btree->u.external[i].file_secno));
+	}
+	for (j = i + 1; j < btree->n_used_nodes; j++)
+		hpfs_free_sectors(s, le32_to_cpu(btree->u.external[j].disk_secno), le32_to_cpu(btree->u.external[j].length));
+	btree->n_used_nodes = i + 1;
+	btree->n_free_nodes = nodes - btree->n_used_nodes;
+	btree->first_free = cpu_to_le16(8 + 12 * btree->n_used_nodes);
+	mark_buffer_dirty(bh);
+	brelse(bh);
+}
+
+/* Remove file or directory and it's eas - note that directory must
+   be empty when this is called. */
+
+void hpfs_remove_fnode(struct super_block *s, fnode_secno fno)
+{
+	struct buffer_head *bh;
+	struct fnode *fnode;
+	struct extended_attribute *ea;
+	struct extended_attribute *ea_end;
+	if (!(fnode = hpfs_map_fnode(s, fno, &bh))) return;
+	if (!fnode_is_dir(fnode)) hpfs_remove_btree(s, &fnode->btree);
+	else hpfs_remove_dtree(s, le32_to_cpu(fnode->u.external[0].disk_secno));
+	ea_end = fnode_end_ea(fnode);
+	for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
+		if (ea_indirect(ea))
+			hpfs_ea_remove(s, ea_sec(ea), ea_in_anode(ea), ea_len(ea));
+	hpfs_ea_ext_remove(s, le32_to_cpu(fnode->ea_secno), fnode_in_anode(fnode), le32_to_cpu(fnode->ea_size_l));
+	brelse(bh);
+	hpfs_free_sectors(s, fno, 1);
+}
diff --git a/fs/hpfs/buffer.c b/fs/hpfs/buffer.c
new file mode 100644
index 0000000000..d39246865c
--- /dev/null
+++ b/fs/hpfs/buffer.c
@@ -0,0 +1,232 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/hpfs/buffer.c
+ *
+ *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
+ *
+ *  general buffer i/o
+ */
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/blkdev.h>
+#include "hpfs_fn.h"
+
+secno hpfs_search_hotfix_map(struct super_block *s, secno sec)
+{
+	unsigned i;
+	struct hpfs_sb_info *sbi = hpfs_sb(s);
+	for (i = 0; unlikely(i < sbi->n_hotfixes); i++) {
+		if (sbi->hotfix_from[i] == sec) {
+			return sbi->hotfix_to[i];
+		}
+	}
+	return sec;
+}
+
+unsigned hpfs_search_hotfix_map_for_range(struct super_block *s, secno sec, unsigned n)
+{
+	unsigned i;
+	struct hpfs_sb_info *sbi = hpfs_sb(s);
+	for (i = 0; unlikely(i < sbi->n_hotfixes); i++) {
+		if (sbi->hotfix_from[i] >= sec && sbi->hotfix_from[i] < sec + n) {
+			n = sbi->hotfix_from[i] - sec;
+		}
+	}
+	return n;
+}
+
+void hpfs_prefetch_sectors(struct super_block *s, unsigned secno, int n)
+{
+	struct buffer_head *bh;
+	struct blk_plug plug;
+
+	if (n <= 0 || unlikely(secno >= hpfs_sb(s)->sb_fs_size))
+		return;
+
+	if (unlikely(hpfs_search_hotfix_map_for_range(s, secno, n) != n))
+		return;
+
+	bh = sb_find_get_block(s, secno);
+	if (bh) {
+		if (buffer_uptodate(bh)) {
+			brelse(bh);
+			return;
+		}
+		brelse(bh);
+	}
+
+	blk_start_plug(&plug);
+	while (n > 0) {
+		if (unlikely(secno >= hpfs_sb(s)->sb_fs_size))
+			break;
+		sb_breadahead(s, secno);
+		secno++;
+		n--;
+	}
+	blk_finish_plug(&plug);
+}
+
+/* Map a sector into a buffer and return pointers to it and to the buffer. */
+
+void *hpfs_map_sector(struct super_block *s, unsigned secno, struct buffer_head **bhp,
+		 int ahead)
+{
+	struct buffer_head *bh;
+
+	hpfs_lock_assert(s);
+
+	hpfs_prefetch_sectors(s, secno, ahead);
+
+	cond_resched();
+
+	*bhp = bh = sb_bread(s, hpfs_search_hotfix_map(s, secno));
+	if (bh != NULL)
+		return bh->b_data;
+	else {
+		pr_err("%s(): read error\n", __func__);
+		return NULL;
+	}
+}
+
+/* Like hpfs_map_sector but don't read anything */
+
+void *hpfs_get_sector(struct super_block *s, unsigned secno, struct buffer_head **bhp)
+{
+	struct buffer_head *bh;
+	/*return hpfs_map_sector(s, secno, bhp, 0);*/
+
+	hpfs_lock_assert(s);
+
+	cond_resched();
+
+	if ((*bhp = bh = sb_getblk(s, hpfs_search_hotfix_map(s, secno))) != NULL) {
+		if (!buffer_uptodate(bh)) wait_on_buffer(bh);
+		set_buffer_uptodate(bh);
+		return bh->b_data;
+	} else {
+		pr_err("%s(): getblk failed\n", __func__);
+		return NULL;
+	}
+}
+
+/* Map 4 sectors into a 4buffer and return pointers to it and to the buffer. */
+
+void *hpfs_map_4sectors(struct super_block *s, unsigned secno, struct quad_buffer_head *qbh,
+		   int ahead)
+{
+	char *data;
+
+	hpfs_lock_assert(s);
+
+	cond_resched();
+
+	if (secno & 3) {
+		pr_err("%s(): unaligned read\n", __func__);
+		return NULL;
+	}
+
+	hpfs_prefetch_sectors(s, secno, 4 + ahead);
+
+	if (!hpfs_map_sector(s, secno + 0, &qbh->bh[0], 0)) goto bail0;
+	if (!hpfs_map_sector(s, secno + 1, &qbh->bh[1], 0)) goto bail1;
+	if (!hpfs_map_sector(s, secno + 2, &qbh->bh[2], 0)) goto bail2;
+	if (!hpfs_map_sector(s, secno + 3, &qbh->bh[3], 0)) goto bail3;
+
+	if (likely(qbh->bh[1]->b_data == qbh->bh[0]->b_data + 1 * 512) &&
+	    likely(qbh->bh[2]->b_data == qbh->bh[0]->b_data + 2 * 512) &&
+	    likely(qbh->bh[3]->b_data == qbh->bh[0]->b_data + 3 * 512)) {
+		return qbh->data = qbh->bh[0]->b_data;
+	}
+
+	qbh->data = data = kmalloc(2048, GFP_NOFS);
+	if (!data) {
+		pr_err("%s(): out of memory\n", __func__);
+		goto bail4;
+	}
+
+	memcpy(data + 0 * 512, qbh->bh[0]->b_data, 512);
+	memcpy(data + 1 * 512, qbh->bh[1]->b_data, 512);
+	memcpy(data + 2 * 512, qbh->bh[2]->b_data, 512);
+	memcpy(data + 3 * 512, qbh->bh[3]->b_data, 512);
+
+	return data;
+
+ bail4:
+	brelse(qbh->bh[3]);
+ bail3:
+	brelse(qbh->bh[2]);
+ bail2:
+	brelse(qbh->bh[1]);
+ bail1:
+	brelse(qbh->bh[0]);
+ bail0:
+	return NULL;
+}
+
+/* Don't read sectors */
+
+void *hpfs_get_4sectors(struct super_block *s, unsigned secno,
+                          struct quad_buffer_head *qbh)
+{
+	cond_resched();
+
+	hpfs_lock_assert(s);
+
+	if (secno & 3) {
+		pr_err("%s(): unaligned read\n", __func__);
+		return NULL;
+	}
+
+	if (!hpfs_get_sector(s, secno + 0, &qbh->bh[0])) goto bail0;
+	if (!hpfs_get_sector(s, secno + 1, &qbh->bh[1])) goto bail1;
+	if (!hpfs_get_sector(s, secno + 2, &qbh->bh[2])) goto bail2;
+	if (!hpfs_get_sector(s, secno + 3, &qbh->bh[3])) goto bail3;
+
+	if (likely(qbh->bh[1]->b_data == qbh->bh[0]->b_data + 1 * 512) &&
+	    likely(qbh->bh[2]->b_data == qbh->bh[0]->b_data + 2 * 512) &&
+	    likely(qbh->bh[3]->b_data == qbh->bh[0]->b_data + 3 * 512)) {
+		return qbh->data = qbh->bh[0]->b_data;
+	}
+
+	if (!(qbh->data = kmalloc(2048, GFP_NOFS))) {
+		pr_err("%s(): out of memory\n", __func__);
+		goto bail4;
+	}
+	return qbh->data;
+
+bail4:
+	brelse(qbh->bh[3]);
+bail3:
+	brelse(qbh->bh[2]);
+bail2:
+	brelse(qbh->bh[1]);
+bail1:
+	brelse(qbh->bh[0]);
+bail0:
+	return NULL;
+}
+	
+
+void hpfs_brelse4(struct quad_buffer_head *qbh)
+{
+	if (unlikely(qbh->data != qbh->bh[0]->b_data))
+		kfree(qbh->data);
+	brelse(qbh->bh[0]);
+	brelse(qbh->bh[1]);
+	brelse(qbh->bh[2]);
+	brelse(qbh->bh[3]);
+}	
+
+void hpfs_mark_4buffers_dirty(struct quad_buffer_head *qbh)
+{
+	if (unlikely(qbh->data != qbh->bh[0]->b_data)) {
+		memcpy(qbh->bh[0]->b_data, qbh->data + 0 * 512, 512);
+		memcpy(qbh->bh[1]->b_data, qbh->data + 1 * 512, 512);
+		memcpy(qbh->bh[2]->b_data, qbh->data + 2 * 512, 512);
+		memcpy(qbh->bh[3]->b_data, qbh->data + 3 * 512, 512);
+	}
+	mark_buffer_dirty(qbh->bh[0]);
+	mark_buffer_dirty(qbh->bh[1]);
+	mark_buffer_dirty(qbh->bh[2]);
+	mark_buffer_dirty(qbh->bh[3]);
+}
diff --git a/fs/hpfs/dentry.c b/fs/hpfs/dentry.c
new file mode 100644
index 0000000000..89a36fdc68
--- /dev/null
+++ b/fs/hpfs/dentry.c
@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/hpfs/dentry.c
+ *
+ *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
+ *
+ *  dcache operations
+ */
+
+#include "hpfs_fn.h"
+
+/*
+ * Note: the dentry argument is the parent dentry.
+ */
+
+static int hpfs_hash_dentry(const struct dentry *dentry, struct qstr *qstr)
+{
+	unsigned long	 hash;
+	int		 i;
+	unsigned l = qstr->len;
+
+	if (l == 1) if (qstr->name[0]=='.') goto x;
+	if (l == 2) if (qstr->name[0]=='.' || qstr->name[1]=='.') goto x;
+	hpfs_adjust_length(qstr->name, &l);
+	/*if (hpfs_chk_name(qstr->name,&l))*/
+		/*return -ENAMETOOLONG;*/
+		/*return -ENOENT;*/
+	x:
+
+	hash = init_name_hash(dentry);
+	for (i = 0; i < l; i++)
+		hash = partial_name_hash(hpfs_upcase(hpfs_sb(dentry->d_sb)->sb_cp_table,qstr->name[i]), hash);
+	qstr->hash = end_name_hash(hash);
+
+	return 0;
+}
+
+static int hpfs_compare_dentry(const struct dentry *dentry,
+		unsigned int len, const char *str, const struct qstr *name)
+{
+	unsigned al = len;
+	unsigned bl = name->len;
+
+	hpfs_adjust_length(str, &al);
+	/*hpfs_adjust_length(b->name, &bl);*/
+
+	/*
+	 * 'str' is the nane of an already existing dentry, so the name
+	 * must be valid. 'name' must be validated first.
+	 */
+
+	if (hpfs_chk_name(name->name, &bl))
+		return 1;
+	if (hpfs_compare_names(dentry->d_sb, str, al, name->name, bl, 0))
+		return 1;
+	return 0;
+}
+
+const struct dentry_operations hpfs_dentry_operations = {
+	.d_hash		= hpfs_hash_dentry,
+	.d_compare	= hpfs_compare_dentry,
+};
diff --git a/fs/hpfs/dir.c b/fs/hpfs/dir.c
new file mode 100644
index 0000000000..f36566d612
--- /dev/null
+++ b/fs/hpfs/dir.c
@@ -0,0 +1,329 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/hpfs/dir.c
+ *
+ *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
+ *
+ *  directory VFS functions
+ */
+
+#include <linux/slab.h>
+#include "hpfs_fn.h"
+
+static int hpfs_dir_release(struct inode *inode, struct file *filp)
+{
+	hpfs_lock(inode->i_sb);
+	hpfs_del_pos(inode, &filp->f_pos);
+	/*hpfs_write_if_changed(inode);*/
+	hpfs_unlock(inode->i_sb);
+	return 0;
+}
+
+/* This is slow, but it's not used often */
+
+static loff_t hpfs_dir_lseek(struct file *filp, loff_t off, int whence)
+{
+	loff_t new_off = off + (whence == 1 ? filp->f_pos : 0);
+	loff_t pos;
+	struct quad_buffer_head qbh;
+	struct inode *i = file_inode(filp);
+	struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
+	struct super_block *s = i->i_sb;
+
+	/* Somebody else will have to figure out what to do here */
+	if (whence == SEEK_DATA || whence == SEEK_HOLE)
+		return -EINVAL;
+
+	inode_lock(i);
+	hpfs_lock(s);
+
+	/*pr_info("dir lseek\n");*/
+	if (new_off == 0 || new_off == 1 || new_off == 11 || new_off == 12 || new_off == 13) goto ok;
+	pos = ((loff_t) hpfs_de_as_down_as_possible(s, hpfs_inode->i_dno) << 4) + 1;
+	while (pos != new_off) {
+		if (map_pos_dirent(i, &pos, &qbh)) hpfs_brelse4(&qbh);
+		else goto fail;
+		if (pos == 12) goto fail;
+	}
+	if (unlikely(hpfs_add_pos(i, &filp->f_pos) < 0)) {
+		hpfs_unlock(s);
+		inode_unlock(i);
+		return -ENOMEM;
+	}
+ok:
+	filp->f_pos = new_off;
+	hpfs_unlock(s);
+	inode_unlock(i);
+	return new_off;
+fail:
+	/*pr_warn("illegal lseek: %016llx\n", new_off);*/
+	hpfs_unlock(s);
+	inode_unlock(i);
+	return -ESPIPE;
+}
+
+static int hpfs_readdir(struct file *file, struct dir_context *ctx)
+{
+	struct inode *inode = file_inode(file);
+	struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
+	struct quad_buffer_head qbh;
+	struct hpfs_dirent *de;
+	int lc;
+	loff_t next_pos;
+	unsigned char *tempname;
+	int c1, c2 = 0;
+	int ret = 0;
+
+	hpfs_lock(inode->i_sb);
+
+	if (hpfs_sb(inode->i_sb)->sb_chk) {
+		if (hpfs_chk_sectors(inode->i_sb, inode->i_ino, 1, "dir_fnode")) {
+			ret = -EFSERROR;
+			goto out;
+		}
+		if (hpfs_chk_sectors(inode->i_sb, hpfs_inode->i_dno, 4, "dir_dnode")) {
+			ret = -EFSERROR;
+			goto out;
+		}
+	}
+	if (hpfs_sb(inode->i_sb)->sb_chk >= 2) {
+		struct buffer_head *bh;
+		struct fnode *fno;
+		int e = 0;
+		if (!(fno = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) {
+			ret = -EIOERROR;
+			goto out;
+		}
+		if (!fnode_is_dir(fno)) {
+			e = 1;
+			hpfs_error(inode->i_sb, "not a directory, fnode %08lx",
+					(unsigned long)inode->i_ino);
+		}
+		if (hpfs_inode->i_dno != le32_to_cpu(fno->u.external[0].disk_secno)) {
+			e = 1;
+			hpfs_error(inode->i_sb, "corrupted inode: i_dno == %08x, fnode -> dnode == %08x", hpfs_inode->i_dno, le32_to_cpu(fno->u.external[0].disk_secno));
+		}
+		brelse(bh);
+		if (e) {
+			ret = -EFSERROR;
+			goto out;
+		}
+	}
+	lc = hpfs_sb(inode->i_sb)->sb_lowercase;
+	if (ctx->pos == 12) { /* diff -r requires this (note, that diff -r */
+		ctx->pos = 13; /* also fails on msdos filesystem in 2.0) */
+		goto out;
+	}
+	if (ctx->pos == 13) {
+		ret = -ENOENT;
+		goto out;
+	}
+	
+	while (1) {
+		again:
+		/* This won't work when cycle is longer than number of dirents
+		   accepted by filldir, but what can I do?
+		   maybe killall -9 ls helps */
+		if (hpfs_sb(inode->i_sb)->sb_chk)
+			if (hpfs_stop_cycles(inode->i_sb, ctx->pos, &c1, &c2, "hpfs_readdir")) {
+				ret = -EFSERROR;
+				goto out;
+			}
+		if (ctx->pos == 12)
+			goto out;
+		if (ctx->pos == 3 || ctx->pos == 4 || ctx->pos == 5) {
+			pr_err("pos==%d\n", (int)ctx->pos);
+			goto out;
+		}
+		if (ctx->pos == 0) {
+			if (!dir_emit_dot(file, ctx))
+				goto out;
+			ctx->pos = 11;
+		}
+		if (ctx->pos == 11) {
+			if (!dir_emit(ctx, "..", 2, hpfs_inode->i_parent_dir, DT_DIR))
+				goto out;
+			ctx->pos = 1;
+		}
+		if (ctx->pos == 1) {
+			ret = hpfs_add_pos(inode, &file->f_pos);
+			if (unlikely(ret < 0))
+				goto out;
+			ctx->pos = ((loff_t) hpfs_de_as_down_as_possible(inode->i_sb, hpfs_inode->i_dno) << 4) + 1;
+		}
+		next_pos = ctx->pos;
+		if (!(de = map_pos_dirent(inode, &next_pos, &qbh))) {
+			ctx->pos = next_pos;
+			ret = -EIOERROR;
+			goto out;
+		}
+		if (de->first || de->last) {
+			if (hpfs_sb(inode->i_sb)->sb_chk) {
+				if (de->first && !de->last && (de->namelen != 2
+				    || de ->name[0] != 1 || de->name[1] != 1))
+					hpfs_error(inode->i_sb, "hpfs_readdir: bad ^A^A entry; pos = %08lx", (unsigned long)ctx->pos);
+				if (de->last && (de->namelen != 1 || de ->name[0] != 255))
+					hpfs_error(inode->i_sb, "hpfs_readdir: bad \\377 entry; pos = %08lx", (unsigned long)ctx->pos);
+			}
+			hpfs_brelse4(&qbh);
+			ctx->pos = next_pos;
+			goto again;
+		}
+		tempname = hpfs_translate_name(inode->i_sb, de->name, de->namelen, lc, de->not_8x3);
+		if (!dir_emit(ctx, tempname, de->namelen, le32_to_cpu(de->fnode), DT_UNKNOWN)) {
+			if (tempname != de->name) kfree(tempname);
+			hpfs_brelse4(&qbh);
+			goto out;
+		}
+		ctx->pos = next_pos;
+		if (tempname != de->name) kfree(tempname);
+		hpfs_brelse4(&qbh);
+	}
+out:
+	hpfs_unlock(inode->i_sb);
+	return ret;
+}
+
+/*
+ * lookup.  Search the specified directory for the specified name, set
+ * *result to the corresponding inode.
+ *
+ * lookup uses the inode number to tell read_inode whether it is reading
+ * the inode of a directory or a file -- file ino's are odd, directory
+ * ino's are even.  read_inode avoids i/o for file inodes; everything
+ * needed is up here in the directory.  (And file fnodes are out in
+ * the boondocks.)
+ *
+ *    - M.P.: this is over, sometimes we've got to read file's fnode for eas
+ *	      inode numbers are just fnode sector numbers; iget lock is used
+ *	      to tell read_inode to read fnode or not.
+ */
+
+struct dentry *hpfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
+{
+	const unsigned char *name = dentry->d_name.name;
+	unsigned len = dentry->d_name.len;
+	struct quad_buffer_head qbh;
+	struct hpfs_dirent *de;
+	ino_t ino;
+	int err;
+	struct inode *result = NULL;
+	struct hpfs_inode_info *hpfs_result;
+
+	hpfs_lock(dir->i_sb);
+	if ((err = hpfs_chk_name(name, &len))) {
+		if (err == -ENAMETOOLONG) {
+			hpfs_unlock(dir->i_sb);
+			return ERR_PTR(-ENAMETOOLONG);
+		}
+		goto end_add;
+	}
+
+	/*
+	 * '.' and '..' will never be passed here.
+	 */
+
+	de = map_dirent(dir, hpfs_i(dir)->i_dno, name, len, NULL, &qbh);
+
+	/*
+	 * This is not really a bailout, just means file not found.
+	 */
+
+	if (!de) goto end;
+
+	/*
+	 * Get inode number, what we're after.
+	 */
+
+	ino = le32_to_cpu(de->fnode);
+
+	/*
+	 * Go find or make an inode.
+	 */
+
+	result = iget_locked(dir->i_sb, ino);
+	if (!result) {
+		hpfs_error(dir->i_sb, "hpfs_lookup: can't get inode");
+		result = ERR_PTR(-ENOMEM);
+		goto bail1;
+	}
+	if (result->i_state & I_NEW) {
+		hpfs_init_inode(result);
+		if (de->directory)
+			hpfs_read_inode(result);
+		else if (le32_to_cpu(de->ea_size) && hpfs_sb(dir->i_sb)->sb_eas)
+			hpfs_read_inode(result);
+		else {
+			result->i_mode |= S_IFREG;
+			result->i_mode &= ~0111;
+			result->i_op = &hpfs_file_iops;
+			result->i_fop = &hpfs_file_ops;
+			set_nlink(result, 1);
+		}
+		unlock_new_inode(result);
+	}
+	hpfs_result = hpfs_i(result);
+	if (!de->directory) hpfs_result->i_parent_dir = dir->i_ino;
+
+	if (de->has_acl || de->has_xtd_perm) if (!sb_rdonly(dir->i_sb)) {
+		hpfs_error(result->i_sb, "ACLs or XPERM found. This is probably HPFS386. This driver doesn't support it now. Send me some info on these structures");
+		iput(result);
+		result = ERR_PTR(-EINVAL);
+		goto bail1;
+	}
+
+	/*
+	 * Fill in the info from the directory if this is a newly created
+	 * inode.
+	 */
+
+	if (!inode_get_ctime(result).tv_sec) {
+		time64_t csec = local_to_gmt(dir->i_sb, le32_to_cpu(de->creation_date));
+
+		inode_set_ctime(result, csec ? csec : 1, 0);
+		result->i_mtime.tv_sec = local_to_gmt(dir->i_sb, le32_to_cpu(de->write_date));
+		result->i_mtime.tv_nsec = 0;
+		result->i_atime.tv_sec = local_to_gmt(dir->i_sb, le32_to_cpu(de->read_date));
+		result->i_atime.tv_nsec = 0;
+		hpfs_result->i_ea_size = le32_to_cpu(de->ea_size);
+		if (!hpfs_result->i_ea_mode && de->read_only)
+			result->i_mode &= ~0222;
+		if (!de->directory) {
+			if (result->i_size == -1) {
+				result->i_size = le32_to_cpu(de->file_size);
+				result->i_data.a_ops = &hpfs_aops;
+				hpfs_i(result)->mmu_private = result->i_size;
+			/*
+			 * i_blocks should count the fnode and any anodes.
+			 * We count 1 for the fnode and don't bother about
+			 * anodes -- the disk heads are on the directory band
+			 * and we want them to stay there.
+			 */
+				result->i_blocks = 1 + ((result->i_size + 511) >> 9);
+			}
+		}
+	}
+
+bail1:
+	hpfs_brelse4(&qbh);
+
+	/*
+	 * Made it.
+	 */
+
+end:
+end_add:
+	hpfs_unlock(dir->i_sb);
+	return d_splice_alias(result, dentry);
+}
+
+const struct file_operations hpfs_dir_ops =
+{
+	.llseek		= hpfs_dir_lseek,
+	.read		= generic_read_dir,
+	.iterate_shared	= hpfs_readdir,
+	.release	= hpfs_dir_release,
+	.fsync		= hpfs_file_fsync,
+	.unlocked_ioctl	= hpfs_ioctl,
+	.compat_ioctl	= compat_ptr_ioctl,
+};
diff --git a/fs/hpfs/dnode.c b/fs/hpfs/dnode.c
new file mode 100644
index 0000000000..4ada525c5c
--- /dev/null
+++ b/fs/hpfs/dnode.c
@@ -0,0 +1,1095 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/hpfs/dnode.c
+ *
+ *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
+ *
+ *  handling directory dnode tree - adding, deleteing & searching for dirents
+ */
+
+#include "hpfs_fn.h"
+
+static loff_t get_pos(struct dnode *d, struct hpfs_dirent *fde)
+{
+	struct hpfs_dirent *de;
+	struct hpfs_dirent *de_end = dnode_end_de(d);
+	int i = 1;
+	for (de = dnode_first_de(d); de < de_end; de = de_next_de(de)) {
+		if (de == fde) return ((loff_t) le32_to_cpu(d->self) << 4) | (loff_t)i;
+		i++;
+	}
+	pr_info("%s(): not_found\n", __func__);
+	return ((loff_t)le32_to_cpu(d->self) << 4) | (loff_t)1;
+}
+
+int hpfs_add_pos(struct inode *inode, loff_t *pos)
+{
+	struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
+	int i = 0;
+	loff_t **ppos;
+
+	if (hpfs_inode->i_rddir_off)
+		for (; hpfs_inode->i_rddir_off[i]; i++)
+			if (hpfs_inode->i_rddir_off[i] == pos)
+				return 0;
+	if (!(i&0x0f)) {
+		ppos = kmalloc_array(i + 0x11, sizeof(loff_t *), GFP_NOFS);
+		if (!ppos) {
+			pr_err("out of memory for position list\n");
+			return -ENOMEM;
+		}
+		if (hpfs_inode->i_rddir_off) {
+			memcpy(ppos, hpfs_inode->i_rddir_off, i * sizeof(loff_t));
+			kfree(hpfs_inode->i_rddir_off);
+		}
+		hpfs_inode->i_rddir_off = ppos;
+	}
+	hpfs_inode->i_rddir_off[i] = pos;
+	hpfs_inode->i_rddir_off[i + 1] = NULL;
+	return 0;
+}
+
+void hpfs_del_pos(struct inode *inode, loff_t *pos)
+{
+	struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
+	loff_t **i, **j;
+
+	if (!hpfs_inode->i_rddir_off) goto not_f;
+	for (i = hpfs_inode->i_rddir_off; *i; i++) if (*i == pos) goto fnd;
+	goto not_f;
+	fnd:
+	for (j = i + 1; *j; j++) ;
+	*i = *(j - 1);
+	*(j - 1) = NULL;
+	if (j - 1 == hpfs_inode->i_rddir_off) {
+		kfree(hpfs_inode->i_rddir_off);
+		hpfs_inode->i_rddir_off = NULL;
+	}
+	return;
+	not_f:
+	/*pr_warn("position pointer %p->%08x not found\n",
+		  pos, (int)*pos);*/
+	return;
+}
+
+static void for_all_poss(struct inode *inode, void (*f)(loff_t *, loff_t, loff_t),
+			 loff_t p1, loff_t p2)
+{
+	struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
+	loff_t **i;
+
+	if (!hpfs_inode->i_rddir_off) return;
+	for (i = hpfs_inode->i_rddir_off; *i; i++) (*f)(*i, p1, p2);
+	return;
+}
+
+static void hpfs_pos_subst(loff_t *p, loff_t f, loff_t t)
+{
+	if (*p == f) *p = t;
+}
+
+/*void hpfs_hpfs_pos_substd(loff_t *p, loff_t f, loff_t t)
+{
+	if ((*p & ~0x3f) == (f & ~0x3f)) *p = (t & ~0x3f) | (*p & 0x3f);
+}*/
+
+static void hpfs_pos_ins(loff_t *p, loff_t d, loff_t c)
+{
+	if ((*p & ~0x3f) == (d & ~0x3f) && (*p & 0x3f) >= (d & 0x3f)) {
+		int n = (*p & 0x3f) + c;
+		if (n > 0x3f)
+			pr_err("%s(): %08x + %d\n",
+				__func__, (int)*p, (int)c >> 8);
+		else
+			*p = (*p & ~0x3f) | n;
+	}
+}
+
+static void hpfs_pos_del(loff_t *p, loff_t d, loff_t c)
+{
+	if ((*p & ~0x3f) == (d & ~0x3f) && (*p & 0x3f) >= (d & 0x3f)) {
+		int n = (*p & 0x3f) - c;
+		if (n < 1)
+			pr_err("%s(): %08x - %d\n",
+				__func__, (int)*p, (int)c >> 8);
+		else
+			*p = (*p & ~0x3f) | n;
+	}
+}
+
+static struct hpfs_dirent *dnode_pre_last_de(struct dnode *d)
+{
+	struct hpfs_dirent *de, *de_end, *dee = NULL, *deee = NULL;
+	de_end = dnode_end_de(d);
+	for (de = dnode_first_de(d); de < de_end; de = de_next_de(de)) {
+		deee = dee; dee = de;
+	}	
+	return deee;
+}
+
+static struct hpfs_dirent *dnode_last_de(struct dnode *d)
+{
+	struct hpfs_dirent *de, *de_end, *dee = NULL;
+	de_end = dnode_end_de(d);
+	for (de = dnode_first_de(d); de < de_end; de = de_next_de(de)) {
+		dee = de;
+	}	
+	return dee;
+}
+
+static void set_last_pointer(struct super_block *s, struct dnode *d, dnode_secno ptr)
+{
+	struct hpfs_dirent *de;
+	if (!(de = dnode_last_de(d))) {
+		hpfs_error(s, "set_last_pointer: empty dnode %08x", le32_to_cpu(d->self));
+		return;
+	}
+	if (hpfs_sb(s)->sb_chk) {
+		if (de->down) {
+			hpfs_error(s, "set_last_pointer: dnode %08x has already last pointer %08x",
+				le32_to_cpu(d->self), de_down_pointer(de));
+			return;
+		}
+		if (le16_to_cpu(de->length) != 32) {
+			hpfs_error(s, "set_last_pointer: bad last dirent in dnode %08x", le32_to_cpu(d->self));
+			return;
+		}
+	}
+	if (ptr) {
+		le32_add_cpu(&d->first_free, 4);
+		if (le32_to_cpu(d->first_free) > 2048) {
+			hpfs_error(s, "set_last_pointer: too long dnode %08x", le32_to_cpu(d->self));
+			le32_add_cpu(&d->first_free, -4);
+			return;
+		}
+		de->length = cpu_to_le16(36);
+		de->down = 1;
+		*(__le32 *)((char *)de + 32) = cpu_to_le32(ptr);
+	}
+}
+
+/* Add an entry to dnode and don't care if it grows over 2048 bytes */
+
+struct hpfs_dirent *hpfs_add_de(struct super_block *s, struct dnode *d,
+				const unsigned char *name,
+				unsigned namelen, secno down_ptr)
+{
+	struct hpfs_dirent *de;
+	struct hpfs_dirent *de_end = dnode_end_de(d);
+	unsigned d_size = de_size(namelen, down_ptr);
+	for (de = dnode_first_de(d); de < de_end; de = de_next_de(de)) {
+		int c = hpfs_compare_names(s, name, namelen, de->name, de->namelen, de->last);
+		if (!c) {
+			hpfs_error(s, "name (%c,%d) already exists in dnode %08x", *name, namelen, le32_to_cpu(d->self));
+			return NULL;
+		}
+		if (c < 0) break;
+	}
+	memmove((char *)de + d_size, de, (char *)de_end - (char *)de);
+	memset(de, 0, d_size);
+	if (down_ptr) {
+		*(__le32 *)((char *)de + d_size - 4) = cpu_to_le32(down_ptr);
+		de->down = 1;
+	}
+	de->length = cpu_to_le16(d_size);
+	de->not_8x3 = hpfs_is_name_long(name, namelen);
+	de->namelen = namelen;
+	memcpy(de->name, name, namelen);
+	le32_add_cpu(&d->first_free, d_size);
+	return de;
+}
+
+/* Delete dirent and don't care about its subtree */
+
+static void hpfs_delete_de(struct super_block *s, struct dnode *d,
+			   struct hpfs_dirent *de)
+{
+	if (de->last) {
+		hpfs_error(s, "attempt to delete last dirent in dnode %08x", le32_to_cpu(d->self));
+		return;
+	}
+	d->first_free = cpu_to_le32(le32_to_cpu(d->first_free) - le16_to_cpu(de->length));
+	memmove(de, de_next_de(de), le32_to_cpu(d->first_free) + (char *)d - (char *)de);
+}
+
+static void fix_up_ptrs(struct super_block *s, struct dnode *d)
+{
+	struct hpfs_dirent *de;
+	struct hpfs_dirent *de_end = dnode_end_de(d);
+	dnode_secno dno = le32_to_cpu(d->self);
+	for (de = dnode_first_de(d); de < de_end; de = de_next_de(de))
+		if (de->down) {
+			struct quad_buffer_head qbh;
+			struct dnode *dd;
+			if ((dd = hpfs_map_dnode(s, de_down_pointer(de), &qbh))) {
+				if (le32_to_cpu(dd->up) != dno || dd->root_dnode) {
+					dd->up = cpu_to_le32(dno);
+					dd->root_dnode = 0;
+					hpfs_mark_4buffers_dirty(&qbh);
+				}
+				hpfs_brelse4(&qbh);
+			}
+		}
+}
+
+/* Add an entry to dnode and do dnode splitting if required */
+
+static int hpfs_add_to_dnode(struct inode *i, dnode_secno dno,
+			     const unsigned char *name, unsigned namelen,
+			     struct hpfs_dirent *new_de, dnode_secno down_ptr)
+{
+	struct quad_buffer_head qbh, qbh1, qbh2;
+	struct dnode *d, *ad, *rd, *nd = NULL;
+	dnode_secno adno, rdno;
+	struct hpfs_dirent *de;
+	struct hpfs_dirent nde;
+	unsigned char *nname;
+	int h;
+	int pos;
+	struct buffer_head *bh;
+	struct fnode *fnode;
+	int c1, c2 = 0;
+	if (!(nname = kmalloc(256, GFP_NOFS))) {
+		pr_err("out of memory, can't add to dnode\n");
+		return 1;
+	}
+	go_up:
+	if (namelen >= 256) {
+		hpfs_error(i->i_sb, "%s(): namelen == %d", __func__, namelen);
+		kfree(nd);
+		kfree(nname);
+		return 1;
+	}
+	if (!(d = hpfs_map_dnode(i->i_sb, dno, &qbh))) {
+		kfree(nd);
+		kfree(nname);
+		return 1;
+	}
+	go_up_a:
+	if (hpfs_sb(i->i_sb)->sb_chk)
+		if (hpfs_stop_cycles(i->i_sb, dno, &c1, &c2, "hpfs_add_to_dnode")) {
+			hpfs_brelse4(&qbh);
+			kfree(nd);
+			kfree(nname);
+			return 1;
+		}
+	if (le32_to_cpu(d->first_free) + de_size(namelen, down_ptr) <= 2048) {
+		loff_t t;
+		copy_de(de=hpfs_add_de(i->i_sb, d, name, namelen, down_ptr), new_de);
+		t = get_pos(d, de);
+		for_all_poss(i, hpfs_pos_ins, t, 1);
+		for_all_poss(i, hpfs_pos_subst, 4, t);
+		for_all_poss(i, hpfs_pos_subst, 5, t + 1);
+		hpfs_mark_4buffers_dirty(&qbh);
+		hpfs_brelse4(&qbh);
+		kfree(nd);
+		kfree(nname);
+		return 0;
+	}
+	if (!nd) if (!(nd = kmalloc(0x924, GFP_NOFS))) {
+		/* 0x924 is a max size of dnode after adding a dirent with
+		   max name length. We alloc this only once. There must
+		   not be any error while splitting dnodes, otherwise the
+		   whole directory, not only file we're adding, would
+		   be lost. */
+		pr_err("out of memory for dnode splitting\n");
+		hpfs_brelse4(&qbh);
+		kfree(nname);
+		return 1;
+	}	
+	memcpy(nd, d, le32_to_cpu(d->first_free));
+	copy_de(de = hpfs_add_de(i->i_sb, nd, name, namelen, down_ptr), new_de);
+	for_all_poss(i, hpfs_pos_ins, get_pos(nd, de), 1);
+	h = ((char *)dnode_last_de(nd) - (char *)nd) / 2 + 10;
+	if (!(ad = hpfs_alloc_dnode(i->i_sb, le32_to_cpu(d->up), &adno, &qbh1))) {
+		hpfs_error(i->i_sb, "unable to alloc dnode - dnode tree will be corrupted");
+		hpfs_brelse4(&qbh);
+		kfree(nd);
+		kfree(nname);
+		return 1;
+	}
+	i->i_size += 2048;
+	i->i_blocks += 4;
+	pos = 1;
+	for (de = dnode_first_de(nd); (char *)de_next_de(de) - (char *)nd < h; de = de_next_de(de)) {
+		copy_de(hpfs_add_de(i->i_sb, ad, de->name, de->namelen, de->down ? de_down_pointer(de) : 0), de);
+		for_all_poss(i, hpfs_pos_subst, ((loff_t)dno << 4) | pos, ((loff_t)adno << 4) | pos);
+		pos++;
+	}
+	copy_de(new_de = &nde, de);
+	memcpy(nname, de->name, de->namelen);
+	name = nname;
+	namelen = de->namelen;
+	for_all_poss(i, hpfs_pos_subst, ((loff_t)dno << 4) | pos, 4);
+	down_ptr = adno;
+	set_last_pointer(i->i_sb, ad, de->down ? de_down_pointer(de) : 0);
+	de = de_next_de(de);
+	memmove((char *)nd + 20, de, le32_to_cpu(nd->first_free) + (char *)nd - (char *)de);
+	le32_add_cpu(&nd->first_free, -((char *)de - (char *)nd - 20));
+	memcpy(d, nd, le32_to_cpu(nd->first_free));
+	for_all_poss(i, hpfs_pos_del, (loff_t)dno << 4, pos);
+	fix_up_ptrs(i->i_sb, ad);
+	if (!d->root_dnode) {
+		ad->up = d->up;
+		dno = le32_to_cpu(ad->up);
+		hpfs_mark_4buffers_dirty(&qbh);
+		hpfs_brelse4(&qbh);
+		hpfs_mark_4buffers_dirty(&qbh1);
+		hpfs_brelse4(&qbh1);
+		goto go_up;
+	}
+	if (!(rd = hpfs_alloc_dnode(i->i_sb, le32_to_cpu(d->up), &rdno, &qbh2))) {
+		hpfs_error(i->i_sb, "unable to alloc dnode - dnode tree will be corrupted");
+		hpfs_brelse4(&qbh);
+		hpfs_brelse4(&qbh1);
+		kfree(nd);
+		kfree(nname);
+		return 1;
+	}
+	i->i_size += 2048;
+	i->i_blocks += 4;
+	rd->root_dnode = 1;
+	rd->up = d->up;
+	if (!(fnode = hpfs_map_fnode(i->i_sb, le32_to_cpu(d->up), &bh))) {
+		hpfs_free_dnode(i->i_sb, rdno);
+		hpfs_brelse4(&qbh);
+		hpfs_brelse4(&qbh1);
+		hpfs_brelse4(&qbh2);
+		kfree(nd);
+		kfree(nname);
+		return 1;
+	}
+	fnode->u.external[0].disk_secno = cpu_to_le32(rdno);
+	mark_buffer_dirty(bh);
+	brelse(bh);
+	hpfs_i(i)->i_dno = rdno;
+	d->up = ad->up = cpu_to_le32(rdno);
+	d->root_dnode = ad->root_dnode = 0;
+	hpfs_mark_4buffers_dirty(&qbh);
+	hpfs_brelse4(&qbh);
+	hpfs_mark_4buffers_dirty(&qbh1);
+	hpfs_brelse4(&qbh1);
+	qbh = qbh2;
+	set_last_pointer(i->i_sb, rd, dno);
+	dno = rdno;
+	d = rd;
+	goto go_up_a;
+}
+
+/*
+ * Add an entry to directory btree.
+ * I hate such crazy directory structure.
+ * It's easy to read but terrible to write.
+ * I wrote this directory code 4 times.
+ * I hope, now it's finally bug-free.
+ */
+
+int hpfs_add_dirent(struct inode *i,
+		    const unsigned char *name, unsigned namelen,
+		    struct hpfs_dirent *new_de)
+{
+	struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
+	struct dnode *d;
+	struct hpfs_dirent *de, *de_end;
+	struct quad_buffer_head qbh;
+	dnode_secno dno;
+	int c;
+	int c1, c2 = 0;
+	dno = hpfs_inode->i_dno;
+	down:
+	if (hpfs_sb(i->i_sb)->sb_chk)
+		if (hpfs_stop_cycles(i->i_sb, dno, &c1, &c2, "hpfs_add_dirent")) return 1;
+	if (!(d = hpfs_map_dnode(i->i_sb, dno, &qbh))) return 1;
+	de_end = dnode_end_de(d);
+	for (de = dnode_first_de(d); de < de_end; de = de_next_de(de)) {
+		if (!(c = hpfs_compare_names(i->i_sb, name, namelen, de->name, de->namelen, de->last))) {
+			hpfs_brelse4(&qbh);
+			return -1;
+		}	
+		if (c < 0) {
+			if (de->down) {
+				dno = de_down_pointer(de);
+				hpfs_brelse4(&qbh);
+				goto down;
+			}
+			break;
+		}
+	}
+	hpfs_brelse4(&qbh);
+	if (hpfs_check_free_dnodes(i->i_sb, FREE_DNODES_ADD)) {
+		c = 1;
+		goto ret;
+	}	
+	c = hpfs_add_to_dnode(i, dno, name, namelen, new_de, 0);
+	ret:
+	return c;
+}
+
+/* 
+ * Find dirent with higher name in 'from' subtree and move it to 'to' dnode.
+ * Return the dnode we moved from (to be checked later if it's empty)
+ */
+
+static secno move_to_top(struct inode *i, dnode_secno from, dnode_secno to)
+{
+	dnode_secno dno, ddno;
+	dnode_secno chk_up = to;
+	struct dnode *dnode;
+	struct quad_buffer_head qbh;
+	struct hpfs_dirent *de, *nde;
+	int a;
+	loff_t t;
+	int c1, c2 = 0;
+	dno = from;
+	while (1) {
+		if (hpfs_sb(i->i_sb)->sb_chk)
+			if (hpfs_stop_cycles(i->i_sb, dno, &c1, &c2, "move_to_top"))
+				return 0;
+		if (!(dnode = hpfs_map_dnode(i->i_sb, dno, &qbh))) return 0;
+		if (hpfs_sb(i->i_sb)->sb_chk) {
+			if (le32_to_cpu(dnode->up) != chk_up) {
+				hpfs_error(i->i_sb, "move_to_top: up pointer from %08x should be %08x, is %08x",
+					dno, chk_up, le32_to_cpu(dnode->up));
+				hpfs_brelse4(&qbh);
+				return 0;
+			}
+			chk_up = dno;
+		}
+		if (!(de = dnode_last_de(dnode))) {
+			hpfs_error(i->i_sb, "move_to_top: dnode %08x has no last de", dno);
+			hpfs_brelse4(&qbh);
+			return 0;
+		}
+		if (!de->down) break;
+		dno = de_down_pointer(de);
+		hpfs_brelse4(&qbh);
+	}
+	while (!(de = dnode_pre_last_de(dnode))) {
+		dnode_secno up = le32_to_cpu(dnode->up);
+		hpfs_brelse4(&qbh);
+		hpfs_free_dnode(i->i_sb, dno);
+		i->i_size -= 2048;
+		i->i_blocks -= 4;
+		for_all_poss(i, hpfs_pos_subst, ((loff_t)dno << 4) | 1, 5);
+		if (up == to) return to;
+		if (!(dnode = hpfs_map_dnode(i->i_sb, up, &qbh))) return 0;
+		if (dnode->root_dnode) {
+			hpfs_error(i->i_sb, "move_to_top: got to root_dnode while moving from %08x to %08x", from, to);
+			hpfs_brelse4(&qbh);
+			return 0;
+		}
+		de = dnode_last_de(dnode);
+		if (!de || !de->down) {
+			hpfs_error(i->i_sb, "move_to_top: dnode %08x doesn't point down to %08x", up, dno);
+			hpfs_brelse4(&qbh);
+			return 0;
+		}
+		le32_add_cpu(&dnode->first_free, -4);
+		le16_add_cpu(&de->length, -4);
+		de->down = 0;
+		hpfs_mark_4buffers_dirty(&qbh);
+		dno = up;
+	}
+	t = get_pos(dnode, de);
+	for_all_poss(i, hpfs_pos_subst, t, 4);
+	for_all_poss(i, hpfs_pos_subst, t + 1, 5);
+	if (!(nde = kmalloc(le16_to_cpu(de->length), GFP_NOFS))) {
+		hpfs_error(i->i_sb, "out of memory for dirent - directory will be corrupted");
+		hpfs_brelse4(&qbh);
+		return 0;
+	}
+	memcpy(nde, de, le16_to_cpu(de->length));
+	ddno = de->down ? de_down_pointer(de) : 0;
+	hpfs_delete_de(i->i_sb, dnode, de);
+	set_last_pointer(i->i_sb, dnode, ddno);
+	hpfs_mark_4buffers_dirty(&qbh);
+	hpfs_brelse4(&qbh);
+	a = hpfs_add_to_dnode(i, to, nde->name, nde->namelen, nde, from);
+	kfree(nde);
+	if (a) return 0;
+	return dno;
+}
+
+/* 
+ * Check if a dnode is empty and delete it from the tree
+ * (chkdsk doesn't like empty dnodes)
+ */
+
+static void delete_empty_dnode(struct inode *i, dnode_secno dno)
+{
+	struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
+	struct quad_buffer_head qbh;
+	struct dnode *dnode;
+	dnode_secno down, up, ndown;
+	int p;
+	struct hpfs_dirent *de;
+	int c1, c2 = 0;
+	try_it_again:
+	if (hpfs_stop_cycles(i->i_sb, dno, &c1, &c2, "delete_empty_dnode")) return;
+	if (!(dnode = hpfs_map_dnode(i->i_sb, dno, &qbh))) return;
+	if (le32_to_cpu(dnode->first_free) > 56) goto end;
+	if (le32_to_cpu(dnode->first_free) == 52 || le32_to_cpu(dnode->first_free) == 56) {
+		struct hpfs_dirent *de_end;
+		int root = dnode->root_dnode;
+		up = le32_to_cpu(dnode->up);
+		de = dnode_first_de(dnode);
+		down = de->down ? de_down_pointer(de) : 0;
+		if (hpfs_sb(i->i_sb)->sb_chk) if (root && !down) {
+			hpfs_error(i->i_sb, "delete_empty_dnode: root dnode %08x is empty", dno);
+			goto end;
+		}
+		hpfs_brelse4(&qbh);
+		hpfs_free_dnode(i->i_sb, dno);
+		i->i_size -= 2048;
+		i->i_blocks -= 4;
+		if (root) {
+			struct fnode *fnode;
+			struct buffer_head *bh;
+			struct dnode *d1;
+			struct quad_buffer_head qbh1;
+			if (hpfs_sb(i->i_sb)->sb_chk)
+				if (up != i->i_ino) {
+					hpfs_error(i->i_sb,
+						   "bad pointer to fnode, dnode %08x, pointing to %08x, should be %08lx",
+						   dno, up,
+						   (unsigned long)i->i_ino);
+					return;
+				}
+			if ((d1 = hpfs_map_dnode(i->i_sb, down, &qbh1))) {
+				d1->up = cpu_to_le32(up);
+				d1->root_dnode = 1;
+				hpfs_mark_4buffers_dirty(&qbh1);
+				hpfs_brelse4(&qbh1);
+			}
+			if ((fnode = hpfs_map_fnode(i->i_sb, up, &bh))) {
+				fnode->u.external[0].disk_secno = cpu_to_le32(down);
+				mark_buffer_dirty(bh);
+				brelse(bh);
+			}
+			hpfs_inode->i_dno = down;
+			for_all_poss(i, hpfs_pos_subst, ((loff_t)dno << 4) | 1, (loff_t) 12);
+			return;
+		}
+		if (!(dnode = hpfs_map_dnode(i->i_sb, up, &qbh))) return;
+		p = 1;
+		de_end = dnode_end_de(dnode);
+		for (de = dnode_first_de(dnode); de < de_end; de = de_next_de(de), p++)
+			if (de->down) if (de_down_pointer(de) == dno) goto fnd;
+		hpfs_error(i->i_sb, "delete_empty_dnode: pointer to dnode %08x not found in dnode %08x", dno, up);
+		goto end;
+		fnd:
+		for_all_poss(i, hpfs_pos_subst, ((loff_t)dno << 4) | 1, ((loff_t)up << 4) | p);
+		if (!down) {
+			de->down = 0;
+			le16_add_cpu(&de->length, -4);
+			le32_add_cpu(&dnode->first_free, -4);
+			memmove(de_next_de(de), (char *)de_next_de(de) + 4,
+				(char *)dnode + le32_to_cpu(dnode->first_free) - (char *)de_next_de(de));
+		} else {
+			struct dnode *d1;
+			struct quad_buffer_head qbh1;
+			*(dnode_secno *) ((void *) de + le16_to_cpu(de->length) - 4) = down;
+			if ((d1 = hpfs_map_dnode(i->i_sb, down, &qbh1))) {
+				d1->up = cpu_to_le32(up);
+				hpfs_mark_4buffers_dirty(&qbh1);
+				hpfs_brelse4(&qbh1);
+			}
+		}
+	} else {
+		hpfs_error(i->i_sb, "delete_empty_dnode: dnode %08x, first_free == %03x", dno, le32_to_cpu(dnode->first_free));
+		goto end;
+	}
+
+	if (!de->last) {
+		struct hpfs_dirent *de_next = de_next_de(de);
+		struct hpfs_dirent *de_cp;
+		struct dnode *d1;
+		struct quad_buffer_head qbh1;
+		if (!de_next->down) goto endm;
+		ndown = de_down_pointer(de_next);
+		if (!(de_cp = kmalloc(le16_to_cpu(de->length), GFP_NOFS))) {
+			pr_err("out of memory for dtree balancing\n");
+			goto endm;
+		}
+		memcpy(de_cp, de, le16_to_cpu(de->length));
+		hpfs_delete_de(i->i_sb, dnode, de);
+		hpfs_mark_4buffers_dirty(&qbh);
+		hpfs_brelse4(&qbh);
+		for_all_poss(i, hpfs_pos_subst, ((loff_t)up << 4) | p, 4);
+		for_all_poss(i, hpfs_pos_del, ((loff_t)up << 4) | p, 1);
+		if (de_cp->down) if ((d1 = hpfs_map_dnode(i->i_sb, de_down_pointer(de_cp), &qbh1))) {
+			d1->up = cpu_to_le32(ndown);
+			hpfs_mark_4buffers_dirty(&qbh1);
+			hpfs_brelse4(&qbh1);
+		}
+		hpfs_add_to_dnode(i, ndown, de_cp->name, de_cp->namelen, de_cp, de_cp->down ? de_down_pointer(de_cp) : 0);
+		/*pr_info("UP-TO-DNODE: %08x (ndown = %08x, down = %08x, dno = %08x)\n",
+		  up, ndown, down, dno);*/
+		dno = up;
+		kfree(de_cp);
+		goto try_it_again;
+	} else {
+		struct hpfs_dirent *de_prev = dnode_pre_last_de(dnode);
+		struct hpfs_dirent *de_cp;
+		struct dnode *d1;
+		struct quad_buffer_head qbh1;
+		dnode_secno dlp;
+		if (!de_prev) {
+			hpfs_error(i->i_sb, "delete_empty_dnode: empty dnode %08x", up);
+			hpfs_mark_4buffers_dirty(&qbh);
+			hpfs_brelse4(&qbh);
+			dno = up;
+			goto try_it_again;
+		}
+		if (!de_prev->down) goto endm;
+		ndown = de_down_pointer(de_prev);
+		if ((d1 = hpfs_map_dnode(i->i_sb, ndown, &qbh1))) {
+			struct hpfs_dirent *del = dnode_last_de(d1);
+			dlp = del->down ? de_down_pointer(del) : 0;
+			if (!dlp && down) {
+				if (le32_to_cpu(d1->first_free) > 2044) {
+					if (hpfs_sb(i->i_sb)->sb_chk >= 2) {
+						pr_err("unbalanced dnode tree, see hpfs.txt 4 more info\n");
+						pr_err("terminating balancing operation\n");
+					}
+					hpfs_brelse4(&qbh1);
+					goto endm;
+				}
+				if (hpfs_sb(i->i_sb)->sb_chk >= 2) {
+					pr_err("unbalanced dnode tree, see hpfs.txt 4 more info\n");
+					pr_err("goin'on\n");
+				}
+				le16_add_cpu(&del->length, 4);
+				del->down = 1;
+				le32_add_cpu(&d1->first_free, 4);
+			}
+			if (dlp && !down) {
+				le16_add_cpu(&del->length, -4);
+				del->down = 0;
+				le32_add_cpu(&d1->first_free, -4);
+			} else if (down)
+				*(__le32 *) ((void *) del + le16_to_cpu(del->length) - 4) = cpu_to_le32(down);
+		} else goto endm;
+		if (!(de_cp = kmalloc(le16_to_cpu(de_prev->length), GFP_NOFS))) {
+			pr_err("out of memory for dtree balancing\n");
+			hpfs_brelse4(&qbh1);
+			goto endm;
+		}
+		hpfs_mark_4buffers_dirty(&qbh1);
+		hpfs_brelse4(&qbh1);
+		memcpy(de_cp, de_prev, le16_to_cpu(de_prev->length));
+		hpfs_delete_de(i->i_sb, dnode, de_prev);
+		if (!de_prev->down) {
+			le16_add_cpu(&de_prev->length, 4);
+			de_prev->down = 1;
+			le32_add_cpu(&dnode->first_free, 4);
+		}
+		*(__le32 *) ((void *) de_prev + le16_to_cpu(de_prev->length) - 4) = cpu_to_le32(ndown);
+		hpfs_mark_4buffers_dirty(&qbh);
+		hpfs_brelse4(&qbh);
+		for_all_poss(i, hpfs_pos_subst, ((loff_t)up << 4) | (p - 1), 4);
+		for_all_poss(i, hpfs_pos_subst, ((loff_t)up << 4) | p, ((loff_t)up << 4) | (p - 1));
+		if (down) if ((d1 = hpfs_map_dnode(i->i_sb, de_down_pointer(de), &qbh1))) {
+			d1->up = cpu_to_le32(ndown);
+			hpfs_mark_4buffers_dirty(&qbh1);
+			hpfs_brelse4(&qbh1);
+		}
+		hpfs_add_to_dnode(i, ndown, de_cp->name, de_cp->namelen, de_cp, dlp);
+		dno = up;
+		kfree(de_cp);
+		goto try_it_again;
+	}
+	endm:
+	hpfs_mark_4buffers_dirty(&qbh);
+	end:
+	hpfs_brelse4(&qbh);
+}
+
+
+/* Delete dirent from directory */
+
+int hpfs_remove_dirent(struct inode *i, dnode_secno dno, struct hpfs_dirent *de,
+		       struct quad_buffer_head *qbh, int depth)
+{
+	struct dnode *dnode = qbh->data;
+	dnode_secno down = 0;
+	loff_t t;
+	if (de->first || de->last) {
+		hpfs_error(i->i_sb, "hpfs_remove_dirent: attempt to delete first or last dirent in dnode %08x", dno);
+		hpfs_brelse4(qbh);
+		return 1;
+	}
+	if (de->down) down = de_down_pointer(de);
+	if (depth && (de->down || (de == dnode_first_de(dnode) && de_next_de(de)->last))) {
+		if (hpfs_check_free_dnodes(i->i_sb, FREE_DNODES_DEL)) {
+			hpfs_brelse4(qbh);
+			return 2;
+		}
+	}
+	for_all_poss(i, hpfs_pos_del, (t = get_pos(dnode, de)) + 1, 1);
+	hpfs_delete_de(i->i_sb, dnode, de);
+	hpfs_mark_4buffers_dirty(qbh);
+	hpfs_brelse4(qbh);
+	if (down) {
+		dnode_secno a = move_to_top(i, down, dno);
+		for_all_poss(i, hpfs_pos_subst, 5, t);
+		if (a) delete_empty_dnode(i, a);
+		return !a;
+	}
+	delete_empty_dnode(i, dno);
+	return 0;
+}
+
+void hpfs_count_dnodes(struct super_block *s, dnode_secno dno, int *n_dnodes,
+		       int *n_subdirs, int *n_items)
+{
+	struct dnode *dnode;
+	struct quad_buffer_head qbh;
+	struct hpfs_dirent *de;
+	dnode_secno ptr, odno = 0;
+	int c1, c2 = 0;
+	int d1, d2 = 0;
+	go_down:
+	if (n_dnodes) (*n_dnodes)++;
+	if (hpfs_sb(s)->sb_chk)
+		if (hpfs_stop_cycles(s, dno, &c1, &c2, "hpfs_count_dnodes #1")) return;
+	ptr = 0;
+	go_up:
+	if (!(dnode = hpfs_map_dnode(s, dno, &qbh))) return;
+	if (hpfs_sb(s)->sb_chk) if (odno && odno != -1 && le32_to_cpu(dnode->up) != odno)
+		hpfs_error(s, "hpfs_count_dnodes: bad up pointer; dnode %08x, down %08x points to %08x", odno, dno, le32_to_cpu(dnode->up));
+	de = dnode_first_de(dnode);
+	if (ptr) while(1) {
+		if (de->down) if (de_down_pointer(de) == ptr) goto process_de;
+		if (de->last) {
+			hpfs_brelse4(&qbh);
+			hpfs_error(s, "hpfs_count_dnodes: pointer to dnode %08x not found in dnode %08x, got here from %08x",
+				ptr, dno, odno);
+			return;
+		}
+		de = de_next_de(de);
+	}
+	next_de:
+	if (de->down) {
+		odno = dno;
+		dno = de_down_pointer(de);
+		hpfs_brelse4(&qbh);
+		goto go_down;
+	}
+	process_de:
+	if (!de->first && !de->last && de->directory && n_subdirs) (*n_subdirs)++;
+	if (!de->first && !de->last && n_items) (*n_items)++;
+	if ((de = de_next_de(de)) < dnode_end_de(dnode)) goto next_de;
+	ptr = dno;
+	dno = le32_to_cpu(dnode->up);
+	if (dnode->root_dnode) {
+		hpfs_brelse4(&qbh);
+		return;
+	}
+	hpfs_brelse4(&qbh);
+	if (hpfs_sb(s)->sb_chk)
+		if (hpfs_stop_cycles(s, ptr, &d1, &d2, "hpfs_count_dnodes #2")) return;
+	odno = -1;
+	goto go_up;
+}
+
+static struct hpfs_dirent *map_nth_dirent(struct super_block *s, dnode_secno dno, int n,
+					  struct quad_buffer_head *qbh, struct dnode **dn)
+{
+	int i;
+	struct hpfs_dirent *de, *de_end;
+	struct dnode *dnode;
+	dnode = hpfs_map_dnode(s, dno, qbh);
+	if (!dnode) return NULL;
+	if (dn) *dn=dnode;
+	de = dnode_first_de(dnode);
+	de_end = dnode_end_de(dnode);
+	for (i = 1; de < de_end; i++, de = de_next_de(de)) {
+		if (i == n) {
+			return de;
+		}	
+		if (de->last) break;
+	}
+	hpfs_brelse4(qbh);
+	hpfs_error(s, "map_nth_dirent: n too high; dnode = %08x, requested %08x", dno, n);
+	return NULL;
+}
+
+dnode_secno hpfs_de_as_down_as_possible(struct super_block *s, dnode_secno dno)
+{
+	struct quad_buffer_head qbh;
+	dnode_secno d = dno;
+	dnode_secno up = 0;
+	struct hpfs_dirent *de;
+	int c1, c2 = 0;
+
+	again:
+	if (hpfs_sb(s)->sb_chk)
+		if (hpfs_stop_cycles(s, d, &c1, &c2, "hpfs_de_as_down_as_possible"))
+			return d;
+	if (!(de = map_nth_dirent(s, d, 1, &qbh, NULL))) return dno;
+	if (hpfs_sb(s)->sb_chk)
+		if (up && le32_to_cpu(((struct dnode *)qbh.data)->up) != up)
+			hpfs_error(s, "hpfs_de_as_down_as_possible: bad up pointer; dnode %08x, down %08x points to %08x", up, d, le32_to_cpu(((struct dnode *)qbh.data)->up));
+	if (!de->down) {
+		hpfs_brelse4(&qbh);
+		return d;
+	}
+	up = d;
+	d = de_down_pointer(de);
+	hpfs_brelse4(&qbh);
+	goto again;
+}
+
+struct hpfs_dirent *map_pos_dirent(struct inode *inode, loff_t *posp,
+				   struct quad_buffer_head *qbh)
+{
+	loff_t pos;
+	unsigned c;
+	dnode_secno dno;
+	struct hpfs_dirent *de, *d;
+	struct hpfs_dirent *up_de;
+	struct hpfs_dirent *end_up_de;
+	struct dnode *dnode;
+	struct dnode *up_dnode;
+	struct quad_buffer_head qbh0;
+
+	pos = *posp;
+	dno = pos >> 6 << 2;
+	pos &= 077;
+	if (!(de = map_nth_dirent(inode->i_sb, dno, pos, qbh, &dnode)))
+		goto bail;
+
+	/* Going to the next dirent */
+	if ((d = de_next_de(de)) < dnode_end_de(dnode)) {
+		if (!(++*posp & 077)) {
+			hpfs_error(inode->i_sb,
+				"map_pos_dirent: pos crossed dnode boundary; pos = %08llx",
+				(unsigned long long)*posp);
+			goto bail;
+		}
+		/* We're going down the tree */
+		if (d->down) {
+			*posp = ((loff_t) hpfs_de_as_down_as_possible(inode->i_sb, de_down_pointer(d)) << 4) + 1;
+		}
+	
+		return de;
+	}
+
+	/* Going up */
+	if (dnode->root_dnode) goto bail;
+
+	if (!(up_dnode = hpfs_map_dnode(inode->i_sb, le32_to_cpu(dnode->up), &qbh0)))
+		goto bail;
+
+	end_up_de = dnode_end_de(up_dnode);
+	c = 0;
+	for (up_de = dnode_first_de(up_dnode); up_de < end_up_de;
+	     up_de = de_next_de(up_de)) {
+		if (!(++c & 077)) hpfs_error(inode->i_sb,
+			"map_pos_dirent: pos crossed dnode boundary; dnode = %08x", le32_to_cpu(dnode->up));
+		if (up_de->down && de_down_pointer(up_de) == dno) {
+			*posp = ((loff_t) le32_to_cpu(dnode->up) << 4) + c;
+			hpfs_brelse4(&qbh0);
+			return de;
+		}
+	}
+	
+	hpfs_error(inode->i_sb, "map_pos_dirent: pointer to dnode %08x not found in parent dnode %08x",
+		dno, le32_to_cpu(dnode->up));
+	hpfs_brelse4(&qbh0);
+	
+	bail:
+	*posp = 12;
+	return de;
+}
+
+/* Find a dirent in tree */
+
+struct hpfs_dirent *map_dirent(struct inode *inode, dnode_secno dno,
+			       const unsigned char *name, unsigned len,
+			       dnode_secno *dd, struct quad_buffer_head *qbh)
+{
+	struct dnode *dnode;
+	struct hpfs_dirent *de;
+	struct hpfs_dirent *de_end;
+	int c1, c2 = 0;
+
+	if (!S_ISDIR(inode->i_mode)) hpfs_error(inode->i_sb, "map_dirent: not a directory\n");
+	again:
+	if (hpfs_sb(inode->i_sb)->sb_chk)
+		if (hpfs_stop_cycles(inode->i_sb, dno, &c1, &c2, "map_dirent")) return NULL;
+	if (!(dnode = hpfs_map_dnode(inode->i_sb, dno, qbh))) return NULL;
+	
+	de_end = dnode_end_de(dnode);
+	for (de = dnode_first_de(dnode); de < de_end; de = de_next_de(de)) {
+		int t = hpfs_compare_names(inode->i_sb, name, len, de->name, de->namelen, de->last);
+		if (!t) {
+			if (dd) *dd = dno;
+			return de;
+		}
+		if (t < 0) {
+			if (de->down) {
+				dno = de_down_pointer(de);
+				hpfs_brelse4(qbh);
+				goto again;
+			}
+		break;
+		}
+	}
+	hpfs_brelse4(qbh);
+	return NULL;
+}
+
+/*
+ * Remove empty directory. In normal cases it is only one dnode with two
+ * entries, but we must handle also such obscure cases when it's a tree
+ * of empty dnodes.
+ */
+
+void hpfs_remove_dtree(struct super_block *s, dnode_secno dno)
+{
+	struct quad_buffer_head qbh;
+	struct dnode *dnode;
+	struct hpfs_dirent *de;
+	dnode_secno d1, d2, rdno = dno;
+	while (1) {
+		if (!(dnode = hpfs_map_dnode(s, dno, &qbh))) return;
+		de = dnode_first_de(dnode);
+		if (de->last) {
+			if (de->down) d1 = de_down_pointer(de);
+			else goto error;
+			hpfs_brelse4(&qbh);
+			hpfs_free_dnode(s, dno);
+			dno = d1;
+		} else break;
+	}
+	if (!de->first) goto error;
+	d1 = de->down ? de_down_pointer(de) : 0;
+	de = de_next_de(de);
+	if (!de->last) goto error;
+	d2 = de->down ? de_down_pointer(de) : 0;
+	hpfs_brelse4(&qbh);
+	hpfs_free_dnode(s, dno);
+	do {
+		while (d1) {
+			if (!(dnode = hpfs_map_dnode(s, dno = d1, &qbh))) return;
+			de = dnode_first_de(dnode);
+			if (!de->last) goto error;
+			d1 = de->down ? de_down_pointer(de) : 0;
+			hpfs_brelse4(&qbh);
+			hpfs_free_dnode(s, dno);
+		}
+		d1 = d2;
+		d2 = 0;
+	} while (d1);
+	return;
+	error:
+	hpfs_brelse4(&qbh);
+	hpfs_free_dnode(s, dno);
+	hpfs_error(s, "directory %08x is corrupted or not empty", rdno);
+}
+
+/* 
+ * Find dirent for specified fnode. Use truncated 15-char name in fnode as
+ * a help for searching.
+ */
+
+struct hpfs_dirent *map_fnode_dirent(struct super_block *s, fnode_secno fno,
+				     struct fnode *f, struct quad_buffer_head *qbh)
+{
+	unsigned char *name1;
+	unsigned char *name2;
+	int name1len, name2len;
+	struct dnode *d;
+	dnode_secno dno, downd;
+	struct fnode *upf;
+	struct buffer_head *bh;
+	struct hpfs_dirent *de, *de_end;
+	int c;
+	int c1, c2 = 0;
+	int d1, d2 = 0;
+	name1 = f->name;
+	if (!(name2 = kmalloc(256, GFP_NOFS))) {
+		pr_err("out of memory, can't map dirent\n");
+		return NULL;
+	}
+	if (f->len <= 15)
+		memcpy(name2, name1, name1len = name2len = f->len);
+	else {
+		memcpy(name2, name1, 15);
+		memset(name2 + 15, 0xff, 256 - 15);
+		/*name2[15] = 0xff;*/
+		name1len = 15; name2len = 256;
+	}
+	if (!(upf = hpfs_map_fnode(s, le32_to_cpu(f->up), &bh))) {
+		kfree(name2);
+		return NULL;
+	}	
+	if (!fnode_is_dir(upf)) {
+		brelse(bh);
+		hpfs_error(s, "fnode %08x has non-directory parent %08x", fno, le32_to_cpu(f->up));
+		kfree(name2);
+		return NULL;
+	}
+	dno = le32_to_cpu(upf->u.external[0].disk_secno);
+	brelse(bh);
+	go_down:
+	downd = 0;
+	go_up:
+	if (!(d = hpfs_map_dnode(s, dno, qbh))) {
+		kfree(name2);
+		return NULL;
+	}
+	de_end = dnode_end_de(d);
+	de = dnode_first_de(d);
+	if (downd) {
+		while (de < de_end) {
+			if (de->down) if (de_down_pointer(de) == downd) goto f;
+			de = de_next_de(de);
+		}
+		hpfs_error(s, "pointer to dnode %08x not found in dnode %08x", downd, dno);
+		hpfs_brelse4(qbh);
+		kfree(name2);
+		return NULL;
+	}
+	next_de:
+	if (le32_to_cpu(de->fnode) == fno) {
+		kfree(name2);
+		return de;
+	}
+	c = hpfs_compare_names(s, name1, name1len, de->name, de->namelen, de->last);
+	if (c < 0 && de->down) {
+		dno = de_down_pointer(de);
+		hpfs_brelse4(qbh);
+		if (hpfs_sb(s)->sb_chk)
+			if (hpfs_stop_cycles(s, dno, &c1, &c2, "map_fnode_dirent #1")) {
+				kfree(name2);
+				return NULL;
+		}
+		goto go_down;
+	}
+	f:
+	if (le32_to_cpu(de->fnode) == fno) {
+		kfree(name2);
+		return de;
+	}
+	c = hpfs_compare_names(s, name2, name2len, de->name, de->namelen, de->last);
+	if (c < 0 && !de->last) goto not_found;
+	if ((de = de_next_de(de)) < de_end) goto next_de;
+	if (d->root_dnode) goto not_found;
+	downd = dno;
+	dno = le32_to_cpu(d->up);
+	hpfs_brelse4(qbh);
+	if (hpfs_sb(s)->sb_chk)
+		if (hpfs_stop_cycles(s, downd, &d1, &d2, "map_fnode_dirent #2")) {
+			kfree(name2);
+			return NULL;
+		}
+	goto go_up;
+	not_found:
+	hpfs_brelse4(qbh);
+	hpfs_error(s, "dirent for fnode %08x not found", fno);
+	kfree(name2);
+	return NULL;
+}
diff --git a/fs/hpfs/ea.c b/fs/hpfs/ea.c
new file mode 100644
index 0000000000..102ba18e56
--- /dev/null
+++ b/fs/hpfs/ea.c
@@ -0,0 +1,368 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/hpfs/ea.c
+ *
+ *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
+ *
+ *  handling extended attributes
+ */
+
+#include "hpfs_fn.h"
+
+/* Remove external extended attributes. ano specifies whether a is a 
+   direct sector where eas starts or an anode */
+
+void hpfs_ea_ext_remove(struct super_block *s, secno a, int ano, unsigned len)
+{
+	unsigned pos = 0;
+	while (pos < len) {
+		char ex[4 + 255 + 1 + 8];
+		struct extended_attribute *ea = (struct extended_attribute *)ex;
+		if (pos + 4 > len) {
+			hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
+				ano ? "anode" : "sectors", a, len);
+			return;
+		}
+		if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return;
+		if (ea_indirect(ea)) {
+			if (ea_valuelen(ea) != 8) {
+				hpfs_error(s, "ea_indirect(ea) set while ea->valuelen!=8, %s %08x, pos %08x",
+					ano ? "anode" : "sectors", a, pos);
+				return;
+			}
+			if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 9, ex+4))
+				return;
+			hpfs_ea_remove(s, ea_sec(ea), ea_in_anode(ea), ea_len(ea));
+		}
+		pos += ea->namelen + ea_valuelen(ea) + 5;
+	}
+	if (!ano) hpfs_free_sectors(s, a, (len+511) >> 9);
+	else {
+		struct buffer_head *bh;
+		struct anode *anode;
+		if ((anode = hpfs_map_anode(s, a, &bh))) {
+			hpfs_remove_btree(s, &anode->btree);
+			brelse(bh);
+			hpfs_free_sectors(s, a, 1);
+		}
+	}
+}
+
+static char *get_indirect_ea(struct super_block *s, int ano, secno a, int size)
+{
+	char *ret;
+	if (!(ret = kmalloc(size + 1, GFP_NOFS))) {
+		pr_err("out of memory for EA\n");
+		return NULL;
+	}
+	if (hpfs_ea_read(s, a, ano, 0, size, ret)) {
+		kfree(ret);
+		return NULL;
+	}
+	ret[size] = 0;
+	return ret;
+}
+
+static void set_indirect_ea(struct super_block *s, int ano, secno a,
+			    const char *data, int size)
+{
+	hpfs_ea_write(s, a, ano, 0, size, data);
+}
+
+/* Read an extended attribute named 'key' into the provided buffer */
+
+int hpfs_read_ea(struct super_block *s, struct fnode *fnode, char *key,
+		char *buf, int size)
+{
+	unsigned pos;
+	int ano, len;
+	secno a;
+	char ex[4 + 255 + 1 + 8];
+	struct extended_attribute *ea;
+	struct extended_attribute *ea_end = fnode_end_ea(fnode);
+	for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
+		if (!strcmp(ea->name, key)) {
+			if (ea_indirect(ea))
+				goto indirect;
+			if (ea_valuelen(ea) >= size)
+				return -EINVAL;
+			memcpy(buf, ea_data(ea), ea_valuelen(ea));
+			buf[ea_valuelen(ea)] = 0;
+			return 0;
+		}
+	a = le32_to_cpu(fnode->ea_secno);
+	len = le32_to_cpu(fnode->ea_size_l);
+	ano = fnode_in_anode(fnode);
+	pos = 0;
+	while (pos < len) {
+		ea = (struct extended_attribute *)ex;
+		if (pos + 4 > len) {
+			hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
+				ano ? "anode" : "sectors", a, len);
+			return -EIO;
+		}
+		if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return -EIO;
+		if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea_indirect(ea) ? 8 : 0), ex + 4))
+			return -EIO;
+		if (!strcmp(ea->name, key)) {
+			if (ea_indirect(ea))
+				goto indirect;
+			if (ea_valuelen(ea) >= size)
+				return -EINVAL;
+			if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea_valuelen(ea), buf))
+				return -EIO;
+			buf[ea_valuelen(ea)] = 0;
+			return 0;
+		}
+		pos += ea->namelen + ea_valuelen(ea) + 5;
+	}
+	return -ENOENT;
+indirect:
+	if (ea_len(ea) >= size)
+		return -EINVAL;
+	if (hpfs_ea_read(s, ea_sec(ea), ea_in_anode(ea), 0, ea_len(ea), buf))
+		return -EIO;
+	buf[ea_len(ea)] = 0;
+	return 0;
+}
+
+/* Read an extended attribute named 'key' */
+char *hpfs_get_ea(struct super_block *s, struct fnode *fnode, char *key, int *size)
+{
+	char *ret;
+	unsigned pos;
+	int ano, len;
+	secno a;
+	struct extended_attribute *ea;
+	struct extended_attribute *ea_end = fnode_end_ea(fnode);
+	for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
+		if (!strcmp(ea->name, key)) {
+			if (ea_indirect(ea))
+				return get_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), *size = ea_len(ea));
+			if (!(ret = kmalloc((*size = ea_valuelen(ea)) + 1, GFP_NOFS))) {
+				pr_err("out of memory for EA\n");
+				return NULL;
+			}
+			memcpy(ret, ea_data(ea), ea_valuelen(ea));
+			ret[ea_valuelen(ea)] = 0;
+			return ret;
+		}
+	a = le32_to_cpu(fnode->ea_secno);
+	len = le32_to_cpu(fnode->ea_size_l);
+	ano = fnode_in_anode(fnode);
+	pos = 0;
+	while (pos < len) {
+		char ex[4 + 255 + 1 + 8];
+		ea = (struct extended_attribute *)ex;
+		if (pos + 4 > len) {
+			hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
+				ano ? "anode" : "sectors", a, len);
+			return NULL;
+		}
+		if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return NULL;
+		if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea_indirect(ea) ? 8 : 0), ex + 4))
+			return NULL;
+		if (!strcmp(ea->name, key)) {
+			if (ea_indirect(ea))
+				return get_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), *size = ea_len(ea));
+			if (!(ret = kmalloc((*size = ea_valuelen(ea)) + 1, GFP_NOFS))) {
+				pr_err("out of memory for EA\n");
+				return NULL;
+			}
+			if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea_valuelen(ea), ret)) {
+				kfree(ret);
+				return NULL;
+			}
+			ret[ea_valuelen(ea)] = 0;
+			return ret;
+		}
+		pos += ea->namelen + ea_valuelen(ea) + 5;
+	}
+	return NULL;
+}
+
+/* 
+ * Update or create extended attribute 'key' with value 'data'. Note that
+ * when this ea exists, it MUST have the same size as size of data.
+ * This driver can't change sizes of eas ('cause I just don't need it).
+ */
+
+void hpfs_set_ea(struct inode *inode, struct fnode *fnode, const char *key,
+		 const char *data, int size)
+{
+	fnode_secno fno = inode->i_ino;
+	struct super_block *s = inode->i_sb;
+	unsigned pos;
+	int ano, len;
+	secno a;
+	unsigned char h[4];
+	struct extended_attribute *ea;
+	struct extended_attribute *ea_end = fnode_end_ea(fnode);
+	for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
+		if (!strcmp(ea->name, key)) {
+			if (ea_indirect(ea)) {
+				if (ea_len(ea) == size)
+					set_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), data, size);
+			} else if (ea_valuelen(ea) == size) {
+				memcpy(ea_data(ea), data, size);
+			}
+			return;
+		}
+	a = le32_to_cpu(fnode->ea_secno);
+	len = le32_to_cpu(fnode->ea_size_l);
+	ano = fnode_in_anode(fnode);
+	pos = 0;
+	while (pos < len) {
+		char ex[4 + 255 + 1 + 8];
+		ea = (struct extended_attribute *)ex;
+		if (pos + 4 > len) {
+			hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
+				ano ? "anode" : "sectors", a, len);
+			return;
+		}
+		if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return;
+		if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea_indirect(ea) ? 8 : 0), ex + 4))
+			return;
+		if (!strcmp(ea->name, key)) {
+			if (ea_indirect(ea)) {
+				if (ea_len(ea) == size)
+					set_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), data, size);
+			}
+			else {
+				if (ea_valuelen(ea) == size)
+					hpfs_ea_write(s, a, ano, pos + 4 + ea->namelen + 1, size, data);
+			}
+			return;
+		}
+		pos += ea->namelen + ea_valuelen(ea) + 5;
+	}
+	if (!le16_to_cpu(fnode->ea_offs)) {
+		/*if (le16_to_cpu(fnode->ea_size_s)) {
+			hpfs_error(s, "fnode %08x: ea_size_s == %03x, ea_offs == 0",
+				inode->i_ino, le16_to_cpu(fnode->ea_size_s));
+			return;
+		}*/
+		fnode->ea_offs = cpu_to_le16(0xc4);
+	}
+	if (le16_to_cpu(fnode->ea_offs) < 0xc4 || le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s) > 0x200) {
+		hpfs_error(s, "fnode %08lx: ea_offs == %03x, ea_size_s == %03x",
+			(unsigned long)inode->i_ino,
+			le16_to_cpu(fnode->ea_offs), le16_to_cpu(fnode->ea_size_s));
+		return;
+	}
+	if ((le16_to_cpu(fnode->ea_size_s) || !le32_to_cpu(fnode->ea_size_l)) &&
+	     le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s) + strlen(key) + size + 5 <= 0x200) {
+		ea = fnode_end_ea(fnode);
+		*(char *)ea = 0;
+		ea->namelen = strlen(key);
+		ea->valuelen_lo = size;
+		ea->valuelen_hi = size >> 8;
+		strcpy(ea->name, key);
+		memcpy(ea_data(ea), data, size);
+		fnode->ea_size_s = cpu_to_le16(le16_to_cpu(fnode->ea_size_s) + strlen(key) + size + 5);
+		goto ret;
+	}
+	/* Most the code here is 99.9993422% unused. I hope there are no bugs.
+	   But what .. HPFS.IFS has also bugs in ea management. */
+	if (le16_to_cpu(fnode->ea_size_s) && !le32_to_cpu(fnode->ea_size_l)) {
+		secno n;
+		struct buffer_head *bh;
+		char *data;
+		if (!(n = hpfs_alloc_sector(s, fno, 1, 0))) return;
+		if (!(data = hpfs_get_sector(s, n, &bh))) {
+			hpfs_free_sectors(s, n, 1);
+			return;
+		}
+		memcpy(data, fnode_ea(fnode), le16_to_cpu(fnode->ea_size_s));
+		fnode->ea_size_l = cpu_to_le32(le16_to_cpu(fnode->ea_size_s));
+		fnode->ea_size_s = cpu_to_le16(0);
+		fnode->ea_secno = cpu_to_le32(n);
+		fnode->flags &= ~FNODE_anode;
+		mark_buffer_dirty(bh);
+		brelse(bh);
+	}
+	pos = le32_to_cpu(fnode->ea_size_l) + 5 + strlen(key) + size;
+	len = (le32_to_cpu(fnode->ea_size_l) + 511) >> 9;
+	if (pos >= 30000) goto bail;
+	while (((pos + 511) >> 9) > len) {
+		if (!len) {
+			secno q = hpfs_alloc_sector(s, fno, 1, 0);
+			if (!q) goto bail;
+			fnode->ea_secno = cpu_to_le32(q);
+			fnode->flags &= ~FNODE_anode;
+			len++;
+		} else if (!fnode_in_anode(fnode)) {
+			if (hpfs_alloc_if_possible(s, le32_to_cpu(fnode->ea_secno) + len)) {
+				len++;
+			} else {
+				/* Aargh... don't know how to create ea anodes :-( */
+				/*struct buffer_head *bh;
+				struct anode *anode;
+				anode_secno a_s;
+				if (!(anode = hpfs_alloc_anode(s, fno, &a_s, &bh)))
+					goto bail;
+				anode->up = cpu_to_le32(fno);
+				anode->btree.fnode_parent = 1;
+				anode->btree.n_free_nodes--;
+				anode->btree.n_used_nodes++;
+				anode->btree.first_free = cpu_to_le16(le16_to_cpu(anode->btree.first_free) + 12);
+				anode->u.external[0].disk_secno = cpu_to_le32(le32_to_cpu(fnode->ea_secno));
+				anode->u.external[0].file_secno = cpu_to_le32(0);
+				anode->u.external[0].length = cpu_to_le32(len);
+				mark_buffer_dirty(bh);
+				brelse(bh);
+				fnode->flags |= FNODE_anode;
+				fnode->ea_secno = cpu_to_le32(a_s);*/
+				secno new_sec;
+				int i;
+				if (!(new_sec = hpfs_alloc_sector(s, fno, 1, 1 - ((pos + 511) >> 9))))
+					goto bail;
+				for (i = 0; i < len; i++) {
+					struct buffer_head *bh1, *bh2;
+					void *b1, *b2;
+					if (!(b1 = hpfs_map_sector(s, le32_to_cpu(fnode->ea_secno) + i, &bh1, len - i - 1))) {
+						hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
+						goto bail;
+					}
+					if (!(b2 = hpfs_get_sector(s, new_sec + i, &bh2))) {
+						brelse(bh1);
+						hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
+						goto bail;
+					}
+					memcpy(b2, b1, 512);
+					brelse(bh1);
+					mark_buffer_dirty(bh2);
+					brelse(bh2);
+				}
+				hpfs_free_sectors(s, le32_to_cpu(fnode->ea_secno), len);
+				fnode->ea_secno = cpu_to_le32(new_sec);
+				len = (pos + 511) >> 9;
+			}
+		}
+		if (fnode_in_anode(fnode)) {
+			if (hpfs_add_sector_to_btree(s, le32_to_cpu(fnode->ea_secno),
+						     0, len) != -1) {
+				len++;
+			} else {
+				goto bail;
+			}
+		}
+	}
+	h[0] = 0;
+	h[1] = strlen(key);
+	h[2] = size & 0xff;
+	h[3] = size >> 8;
+	if (hpfs_ea_write(s, le32_to_cpu(fnode->ea_secno), fnode_in_anode(fnode), le32_to_cpu(fnode->ea_size_l), 4, h)) goto bail;
+	if (hpfs_ea_write(s, le32_to_cpu(fnode->ea_secno), fnode_in_anode(fnode), le32_to_cpu(fnode->ea_size_l) + 4, h[1] + 1, key)) goto bail;
+	if (hpfs_ea_write(s, le32_to_cpu(fnode->ea_secno), fnode_in_anode(fnode), le32_to_cpu(fnode->ea_size_l) + 5 + h[1], size, data)) goto bail;
+	fnode->ea_size_l = cpu_to_le32(pos);
+	ret:
+	hpfs_i(inode)->i_ea_size += 5 + strlen(key) + size;
+	return;
+	bail:
+	if (le32_to_cpu(fnode->ea_secno))
+		if (fnode_in_anode(fnode)) hpfs_truncate_btree(s, le32_to_cpu(fnode->ea_secno), 1, (le32_to_cpu(fnode->ea_size_l) + 511) >> 9);
+		else hpfs_free_sectors(s, le32_to_cpu(fnode->ea_secno) + ((le32_to_cpu(fnode->ea_size_l) + 511) >> 9), len - ((le32_to_cpu(fnode->ea_size_l) + 511) >> 9));
+	else fnode->ea_secno = fnode->ea_size_l = cpu_to_le32(0);
+}
+	
diff --git a/fs/hpfs/file.c b/fs/hpfs/file.c
new file mode 100644
index 0000000000..1bb8d97cd9
--- /dev/null
+++ b/fs/hpfs/file.c
@@ -0,0 +1,271 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/hpfs/file.c
+ *
+ *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
+ *
+ *  file VFS functions
+ */
+
+#include "hpfs_fn.h"
+#include <linux/mpage.h>
+#include <linux/iomap.h>
+#include <linux/fiemap.h>
+
+#define BLOCKS(size) (((size) + 511) >> 9)
+
+static int hpfs_file_release(struct inode *inode, struct file *file)
+{
+	hpfs_lock(inode->i_sb);
+	hpfs_write_if_changed(inode);
+	hpfs_unlock(inode->i_sb);
+	return 0;
+}
+
+int hpfs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync)
+{
+	struct inode *inode = file->f_mapping->host;
+	int ret;
+
+	ret = file_write_and_wait_range(file, start, end);
+	if (ret)
+		return ret;
+	return sync_blockdev(inode->i_sb->s_bdev);
+}
+
+/*
+ * generic_file_read often calls bmap with non-existing sector,
+ * so we must ignore such errors.
+ */
+
+static secno hpfs_bmap(struct inode *inode, unsigned file_secno, unsigned *n_secs)
+{
+	struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
+	unsigned n, disk_secno;
+	struct fnode *fnode;
+	struct buffer_head *bh;
+	if (BLOCKS(hpfs_i(inode)->mmu_private) <= file_secno) return 0;
+	n = file_secno - hpfs_inode->i_file_sec;
+	if (n < hpfs_inode->i_n_secs) {
+		*n_secs = hpfs_inode->i_n_secs - n;
+		return hpfs_inode->i_disk_sec + n;
+	}
+	if (!(fnode = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) return 0;
+	disk_secno = hpfs_bplus_lookup(inode->i_sb, inode, &fnode->btree, file_secno, bh);
+	if (disk_secno == -1) return 0;
+	if (hpfs_chk_sectors(inode->i_sb, disk_secno, 1, "bmap")) return 0;
+	n = file_secno - hpfs_inode->i_file_sec;
+	if (n < hpfs_inode->i_n_secs) {
+		*n_secs = hpfs_inode->i_n_secs - n;
+		return hpfs_inode->i_disk_sec + n;
+	}
+	*n_secs = 1;
+	return disk_secno;
+}
+
+void hpfs_truncate(struct inode *i)
+{
+	if (IS_IMMUTABLE(i)) return /*-EPERM*/;
+	hpfs_lock_assert(i->i_sb);
+
+	hpfs_i(i)->i_n_secs = 0;
+	i->i_blocks = 1 + ((i->i_size + 511) >> 9);
+	hpfs_i(i)->mmu_private = i->i_size;
+	hpfs_truncate_btree(i->i_sb, i->i_ino, 1, ((i->i_size + 511) >> 9));
+	hpfs_write_inode(i);
+	hpfs_i(i)->i_n_secs = 0;
+}
+
+static int hpfs_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create)
+{
+	int r;
+	secno s;
+	unsigned n_secs;
+	hpfs_lock(inode->i_sb);
+	s = hpfs_bmap(inode, iblock, &n_secs);
+	if (s) {
+		if (bh_result->b_size >> 9 < n_secs)
+			n_secs = bh_result->b_size >> 9;
+		n_secs = hpfs_search_hotfix_map_for_range(inode->i_sb, s, n_secs);
+		if (unlikely(!n_secs)) {
+			s = hpfs_search_hotfix_map(inode->i_sb, s);
+			n_secs = 1;
+		}
+		map_bh(bh_result, inode->i_sb, s);
+		bh_result->b_size = n_secs << 9;
+		goto ret_0;
+	}
+	if (!create) goto ret_0;
+	if (iblock<<9 != hpfs_i(inode)->mmu_private) {
+		BUG();
+		r = -EIO;
+		goto ret_r;
+	}
+	if ((s = hpfs_add_sector_to_btree(inode->i_sb, inode->i_ino, 1, inode->i_blocks - 1)) == -1) {
+		hpfs_truncate_btree(inode->i_sb, inode->i_ino, 1, inode->i_blocks - 1);
+		r = -ENOSPC;
+		goto ret_r;
+	}
+	inode->i_blocks++;
+	hpfs_i(inode)->mmu_private += 512;
+	set_buffer_new(bh_result);
+	map_bh(bh_result, inode->i_sb, hpfs_search_hotfix_map(inode->i_sb, s));
+	ret_0:
+	r = 0;
+	ret_r:
+	hpfs_unlock(inode->i_sb);
+	return r;
+}
+
+static int hpfs_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
+		unsigned flags, struct iomap *iomap, struct iomap *srcmap)
+{
+	struct super_block *sb = inode->i_sb;
+	unsigned int blkbits = inode->i_blkbits;
+	unsigned int n_secs;
+	secno s;
+
+	if (WARN_ON_ONCE(flags & (IOMAP_WRITE | IOMAP_ZERO)))
+		return -EINVAL;
+
+	iomap->bdev = inode->i_sb->s_bdev;
+	iomap->offset = offset;
+
+	hpfs_lock(sb);
+	s = hpfs_bmap(inode, offset >> blkbits, &n_secs);
+	if (s) {
+		n_secs = hpfs_search_hotfix_map_for_range(sb, s,
+				min_t(loff_t, n_secs, length));
+		if (unlikely(!n_secs)) {
+			s = hpfs_search_hotfix_map(sb, s);
+			n_secs = 1;
+		}
+		iomap->type = IOMAP_MAPPED;
+		iomap->flags = IOMAP_F_MERGED;
+		iomap->addr = (u64)s << blkbits;
+		iomap->length = (u64)n_secs << blkbits;
+	} else {
+		iomap->type = IOMAP_HOLE;
+		iomap->addr = IOMAP_NULL_ADDR;
+		iomap->length = 1 << blkbits;
+	}
+
+	hpfs_unlock(sb);
+	return 0;
+}
+
+static const struct iomap_ops hpfs_iomap_ops = {
+	.iomap_begin		= hpfs_iomap_begin,
+};
+
+static int hpfs_read_folio(struct file *file, struct folio *folio)
+{
+	return mpage_read_folio(folio, hpfs_get_block);
+}
+
+static void hpfs_readahead(struct readahead_control *rac)
+{
+	mpage_readahead(rac, hpfs_get_block);
+}
+
+static int hpfs_writepages(struct address_space *mapping,
+			   struct writeback_control *wbc)
+{
+	return mpage_writepages(mapping, wbc, hpfs_get_block);
+}
+
+static void hpfs_write_failed(struct address_space *mapping, loff_t to)
+{
+	struct inode *inode = mapping->host;
+
+	hpfs_lock(inode->i_sb);
+
+	if (to > inode->i_size) {
+		truncate_pagecache(inode, inode->i_size);
+		hpfs_truncate(inode);
+	}
+
+	hpfs_unlock(inode->i_sb);
+}
+
+static int hpfs_write_begin(struct file *file, struct address_space *mapping,
+			loff_t pos, unsigned len,
+			struct page **pagep, void **fsdata)
+{
+	int ret;
+
+	*pagep = NULL;
+	ret = cont_write_begin(file, mapping, pos, len, pagep, fsdata,
+				hpfs_get_block,
+				&hpfs_i(mapping->host)->mmu_private);
+	if (unlikely(ret))
+		hpfs_write_failed(mapping, pos + len);
+
+	return ret;
+}
+
+static int hpfs_write_end(struct file *file, struct address_space *mapping,
+			loff_t pos, unsigned len, unsigned copied,
+			struct page *pagep, void *fsdata)
+{
+	struct inode *inode = mapping->host;
+	int err;
+	err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata);
+	if (err < len)
+		hpfs_write_failed(mapping, pos + len);
+	if (!(err < 0)) {
+		/* make sure we write it on close, if not earlier */
+		hpfs_lock(inode->i_sb);
+		hpfs_i(inode)->i_dirty = 1;
+		hpfs_unlock(inode->i_sb);
+	}
+	return err;
+}
+
+static sector_t _hpfs_bmap(struct address_space *mapping, sector_t block)
+{
+	return generic_block_bmap(mapping, block, hpfs_get_block);
+}
+
+static int hpfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, u64 start, u64 len)
+{
+	int ret;
+
+	inode_lock(inode);
+	len = min_t(u64, len, i_size_read(inode));
+	ret = iomap_fiemap(inode, fieinfo, start, len, &hpfs_iomap_ops);
+	inode_unlock(inode);
+
+	return ret;
+}
+
+const struct address_space_operations hpfs_aops = {
+	.dirty_folio	= block_dirty_folio,
+	.invalidate_folio = block_invalidate_folio,
+	.read_folio = hpfs_read_folio,
+	.readahead = hpfs_readahead,
+	.writepages = hpfs_writepages,
+	.write_begin = hpfs_write_begin,
+	.write_end = hpfs_write_end,
+	.bmap = _hpfs_bmap,
+	.migrate_folio = buffer_migrate_folio,
+};
+
+const struct file_operations hpfs_file_ops =
+{
+	.llseek		= generic_file_llseek,
+	.read_iter	= generic_file_read_iter,
+	.write_iter	= generic_file_write_iter,
+	.mmap		= generic_file_mmap,
+	.release	= hpfs_file_release,
+	.fsync		= hpfs_file_fsync,
+	.splice_read	= filemap_splice_read,
+	.unlocked_ioctl	= hpfs_ioctl,
+	.compat_ioctl	= compat_ptr_ioctl,
+};
+
+const struct inode_operations hpfs_file_iops =
+{
+	.setattr	= hpfs_setattr,
+	.fiemap		= hpfs_fiemap,
+};
diff --git a/fs/hpfs/hpfs.h b/fs/hpfs/hpfs.h
new file mode 100644
index 0000000000..281dec8f63
--- /dev/null
+++ b/fs/hpfs/hpfs.h
@@ -0,0 +1,561 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ *  linux/fs/hpfs/hpfs.h
+ *
+ *  HPFS structures by Chris Smith, 1993
+ *
+ *  a little bit modified by Mikulas Patocka, 1998-1999
+ */
+
+/* The paper
+
+     Duncan, Roy
+     Design goals and implementation of the new High Performance File System
+     Microsoft Systems Journal  Sept 1989  v4 n5 p1(13)
+
+   describes what HPFS looked like when it was new, and it is the source
+   of most of the information given here.  The rest is conjecture.
+
+   For definitive information on the Duncan paper, see it, not this file.
+   For definitive information on HPFS, ask somebody else -- this is guesswork.
+   There are certain to be many mistakes. */
+
+#if !defined(__LITTLE_ENDIAN) && !defined(__BIG_ENDIAN)
+#error unknown endian
+#endif
+
+/* Notation */
+
+typedef u32 secno;			/* sector number, partition relative */
+
+typedef secno dnode_secno;		/* sector number of a dnode */
+typedef secno fnode_secno;		/* sector number of an fnode */
+typedef secno anode_secno;		/* sector number of an anode */
+
+typedef u32 time32_t;		/* 32-bit time_t type */
+
+/* sector 0 */
+
+/* The boot block is very like a FAT boot block, except that the
+   29h signature byte is 28h instead, and the ID string is "HPFS". */
+
+#define BB_MAGIC 0xaa55
+
+struct hpfs_boot_block
+{
+  u8 jmp[3];
+  u8 oem_id[8];
+  u8 bytes_per_sector[2];	/* 512 */
+  u8 sectors_per_cluster;
+  u8 n_reserved_sectors[2];
+  u8 n_fats;
+  u8 n_rootdir_entries[2];
+  u8 n_sectors_s[2];
+  u8 media_byte;
+  __le16 sectors_per_fat;
+  __le16 sectors_per_track;
+  __le16 heads_per_cyl;
+  __le32 n_hidden_sectors;
+  __le32 n_sectors_l;		/* size of partition */
+  u8 drive_number;
+  u8 mbz;
+  u8 sig_28h;			/* 28h */
+  u8 vol_serno[4];
+  u8 vol_label[11];
+  u8 sig_hpfs[8];		/* "HPFS    " */
+  u8 pad[448];
+  __le16 magic;			/* aa55 */
+};
+
+
+/* sector 16 */
+
+/* The super block has the pointer to the root directory. */
+
+#define SB_MAGIC 0xf995e849
+
+struct hpfs_super_block
+{
+  __le32 magic;				/* f995 e849 */
+  __le32 magic1;			/* fa53 e9c5, more magic? */
+  u8 version;				/* version of a filesystem  usually 2 */
+  u8 funcversion;			/* functional version - oldest version
+  					   of filesystem that can understand
+					   this disk */
+  __le16 zero;				/* 0 */
+  __le32 root;				/* fnode of root directory */
+  __le32 n_sectors;			/* size of filesystem */
+  __le32 n_badblocks;			/* number of bad blocks */
+  __le32 bitmaps;			/* pointers to free space bit maps */
+  __le32 zero1;				/* 0 */
+  __le32 badblocks;			/* bad block list */
+  __le32 zero3;				/* 0 */
+  __le32 last_chkdsk;			/* date last checked, 0 if never */
+  __le32 last_optimize;			/* date last optimized, 0 if never */
+  __le32 n_dir_band;			/* number of sectors in dir band */
+  __le32 dir_band_start;			/* first sector in dir band */
+  __le32 dir_band_end;			/* last sector in dir band */
+  __le32 dir_band_bitmap;		/* free space map, 1 dnode per bit */
+  u8 volume_name[32];			/* not used */
+  __le32 user_id_table;			/* 8 preallocated sectors - user id */
+  u32 zero6[103];			/* 0 */
+};
+
+
+/* sector 17 */
+
+/* The spare block has pointers to spare sectors.  */
+
+#define SP_MAGIC 0xf9911849
+
+struct hpfs_spare_block
+{
+  __le32 magic;				/* f991 1849 */
+  __le32 magic1;				/* fa52 29c5, more magic? */
+
+#ifdef __LITTLE_ENDIAN
+  u8 dirty: 1;				/* 0 clean, 1 "improperly stopped" */
+  u8 sparedir_used: 1;			/* spare dirblks used */
+  u8 hotfixes_used: 1;			/* hotfixes used */
+  u8 bad_sector: 1;			/* bad sector, corrupted disk (???) */
+  u8 bad_bitmap: 1;			/* bad bitmap */
+  u8 fast: 1;				/* partition was fast formatted */
+  u8 old_wrote: 1;			/* old version wrote to partition */
+  u8 old_wrote_1: 1;			/* old version wrote to partition (?) */
+#else
+  u8 old_wrote_1: 1;			/* old version wrote to partition (?) */
+  u8 old_wrote: 1;			/* old version wrote to partition */
+  u8 fast: 1;				/* partition was fast formatted */
+  u8 bad_bitmap: 1;			/* bad bitmap */
+  u8 bad_sector: 1;			/* bad sector, corrupted disk (???) */
+  u8 hotfixes_used: 1;			/* hotfixes used */
+  u8 sparedir_used: 1;			/* spare dirblks used */
+  u8 dirty: 1;				/* 0 clean, 1 "improperly stopped" */
+#endif
+
+#ifdef __LITTLE_ENDIAN
+  u8 install_dasd_limits: 1;		/* HPFS386 flags */
+  u8 resynch_dasd_limits: 1;
+  u8 dasd_limits_operational: 1;
+  u8 multimedia_active: 1;
+  u8 dce_acls_active: 1;
+  u8 dasd_limits_dirty: 1;
+  u8 flag67: 2;
+#else
+  u8 flag67: 2;
+  u8 dasd_limits_dirty: 1;
+  u8 dce_acls_active: 1;
+  u8 multimedia_active: 1;
+  u8 dasd_limits_operational: 1;
+  u8 resynch_dasd_limits: 1;
+  u8 install_dasd_limits: 1;		/* HPFS386 flags */
+#endif
+
+  u8 mm_contlgulty;
+  u8 unused;
+
+  __le32 hotfix_map;			/* info about remapped bad sectors */
+  __le32 n_spares_used;			/* number of hotfixes */
+  __le32 n_spares;			/* number of spares in hotfix map */
+  __le32 n_dnode_spares_free;		/* spare dnodes unused */
+  __le32 n_dnode_spares;		/* length of spare_dnodes[] list,
+					   follows in this block*/
+  __le32 code_page_dir;			/* code page directory block */
+  __le32 n_code_pages;			/* number of code pages */
+  __le32 super_crc;			/* on HPFS386 and LAN Server this is
+  					   checksum of superblock, on normal
+					   OS/2 unused */
+  __le32 spare_crc;			/* on HPFS386 checksum of spareblock */
+  __le32 zero1[15];			/* unused */
+  __le32 spare_dnodes[100];		/* emergency free dnode list */
+  __le32 zero2[1];			/* room for more? */
+};
+
+/* The bad block list is 4 sectors long.  The first word must be zero,
+   the remaining words give n_badblocks bad block numbers.
+   I bet you can see it coming... */
+
+#define BAD_MAGIC 0
+       
+/* The hotfix map is 4 sectors long.  It looks like
+
+       secno from[n_spares];
+       secno to[n_spares];
+
+   The to[] list is initialized to point to n_spares preallocated empty
+   sectors.  The from[] list contains the sector numbers of bad blocks
+   which have been remapped to corresponding sectors in the to[] list.
+   n_spares_used gives the length of the from[] list. */
+
+
+/* Sectors 18 and 19 are preallocated and unused.
+   Maybe they're spares for 16 and 17, but simple substitution fails. */
+
+
+/* The code page info pointed to by the spare block consists of an index
+   block and blocks containing uppercasing tables.  I don't know what
+   these are for (CHKDSK, maybe?) -- OS/2 does not seem to use them
+   itself.  Linux doesn't use them either. */
+
+/* block pointed to by spareblock->code_page_dir */
+
+#define CP_DIR_MAGIC 0x494521f7
+
+struct code_page_directory
+{
+  __le32 magic;				/* 4945 21f7 */
+  __le32 n_code_pages;			/* number of pointers following */
+  __le32 zero1[2];
+  struct {
+    __le16 ix;				/* index */
+    __le16 code_page_number;		/* code page number */
+    __le32 bounds;			/* matches corresponding word
+					   in data block */
+    __le32 code_page_data;		/* sector number of a code_page_data
+					   containing c.p. array */
+    __le16 index;			/* index in c.p. array in that sector*/
+    __le16 unknown;			/* some unknown value; usually 0;
+    					   2 in Japanese version */
+  } array[31];				/* unknown length */
+};
+
+/* blocks pointed to by code_page_directory */
+
+#define CP_DATA_MAGIC 0x894521f7
+
+struct code_page_data
+{
+  __le32 magic;				/* 8945 21f7 */
+  __le32 n_used;			/* # elements used in c_p_data[] */
+  __le32 bounds[3];			/* looks a bit like
+					     (beg1,end1), (beg2,end2)
+					   one byte each */
+  __le16 offs[3];			/* offsets from start of sector
+					   to start of c_p_data[ix] */
+  struct {
+    __le16 ix;				/* index */
+    __le16 code_page_number;		/* code page number */
+    __le16 unknown;			/* the same as in cp directory */
+    u8 map[128];			/* upcase table for chars 80..ff */
+    __le16 zero2;
+  } code_page[3];
+  u8 incognita[78];
+};
+
+
+/* Free space bitmaps are 4 sectors long, which is 16384 bits.
+   16384 sectors is 8 meg, and each 8 meg band has a 4-sector bitmap.
+   Bit order in the maps is little-endian.  0 means taken, 1 means free.
+
+   Bit map sectors are marked allocated in the bit maps, and so are sectors 
+   off the end of the partition.
+
+   Band 0 is sectors 0-3fff, its map is in sectors 18-1b.
+   Band 1 is 4000-7fff, its map is in 7ffc-7fff.
+   Band 2 is 8000-ffff, its map is in 8000-8003.
+   The remaining bands have maps in their first (even) or last (odd) 4 sectors
+     -- if the last, partial, band is odd its map is in its last 4 sectors.
+
+   The bitmap locations are given in a table pointed to by the super block.
+   No doubt they aren't constrained to be at 18, 7ffc, 8000, ...; that is
+   just where they usually are.
+
+   The "directory band" is a bunch of sectors preallocated for dnodes.
+   It has a 4-sector free space bitmap of its own.  Each bit in the map
+   corresponds to one 4-sector dnode, bit 0 of the map corresponding to
+   the first 4 sectors of the directory band.  The entire band is marked
+   allocated in the main bitmap.   The super block gives the locations
+   of the directory band and its bitmap.  ("band" doesn't mean it is
+   8 meg long; it isn't.)  */
+
+
+/* dnode: directory.  4 sectors long */
+
+/* A directory is a tree of dnodes.  The fnode for a directory
+   contains one pointer, to the root dnode of the tree.  The fnode
+   never moves, the dnodes do the B-tree thing, splitting and merging
+   as files are added and removed.  */
+
+#define DNODE_MAGIC   0x77e40aae
+
+struct dnode {
+  __le32 magic;				/* 77e4 0aae */
+  __le32 first_free;			/* offset from start of dnode to
+					   first free dir entry */
+#ifdef __LITTLE_ENDIAN
+  u8 root_dnode: 1;			/* Is it root dnode? */
+  u8 increment_me: 7;			/* some kind of activity counter? */
+					/* Neither HPFS.IFS nor CHKDSK cares
+					   if you change this word */
+#else
+  u8 increment_me: 7;			/* some kind of activity counter? */
+					/* Neither HPFS.IFS nor CHKDSK cares
+					   if you change this word */
+  u8 root_dnode: 1;			/* Is it root dnode? */
+#endif
+  u8 increment_me2[3];
+  __le32 up;				/* (root dnode) directory's fnode
+					   (nonroot) parent dnode */
+  __le32 self;			/* pointer to this dnode */
+  u8 dirent[2028];			/* one or more dirents */
+};
+
+struct hpfs_dirent {
+  __le16 length;			/* offset to next dirent */
+
+#ifdef __LITTLE_ENDIAN
+  u8 first: 1;				/* set on phony ^A^A (".") entry */
+  u8 has_acl: 1;
+  u8 down: 1;				/* down pointer present (after name) */
+  u8 last: 1;				/* set on phony \377 entry */
+  u8 has_ea: 1;				/* entry has EA */
+  u8 has_xtd_perm: 1;			/* has extended perm list (???) */
+  u8 has_explicit_acl: 1;
+  u8 has_needea: 1;			/* ?? some EA has NEEDEA set
+					   I have no idea why this is
+					   interesting in a dir entry */
+#else
+  u8 has_needea: 1;			/* ?? some EA has NEEDEA set
+					   I have no idea why this is
+					   interesting in a dir entry */
+  u8 has_explicit_acl: 1;
+  u8 has_xtd_perm: 1;			/* has extended perm list (???) */
+  u8 has_ea: 1;				/* entry has EA */
+  u8 last: 1;				/* set on phony \377 entry */
+  u8 down: 1;				/* down pointer present (after name) */
+  u8 has_acl: 1;
+  u8 first: 1;				/* set on phony ^A^A (".") entry */
+#endif
+
+#ifdef __LITTLE_ENDIAN
+  u8 read_only: 1;			/* dos attrib */
+  u8 hidden: 1;				/* dos attrib */
+  u8 system: 1;				/* dos attrib */
+  u8 flag11: 1;				/* would be volume label dos attrib */
+  u8 directory: 1;			/* dos attrib */
+  u8 archive: 1;			/* dos attrib */
+  u8 not_8x3: 1;			/* name is not 8.3 */
+  u8 flag15: 1;
+#else
+  u8 flag15: 1;
+  u8 not_8x3: 1;			/* name is not 8.3 */
+  u8 archive: 1;			/* dos attrib */
+  u8 directory: 1;			/* dos attrib */
+  u8 flag11: 1;				/* would be volume label dos attrib */
+  u8 system: 1;				/* dos attrib */
+  u8 hidden: 1;				/* dos attrib */
+  u8 read_only: 1;			/* dos attrib */
+#endif
+
+  __le32 fnode;				/* fnode giving allocation info */
+  __le32 write_date;			/* mtime */
+  __le32 file_size;			/* file length, bytes */
+  __le32 read_date;			/* atime */
+  __le32 creation_date;			/* ctime */
+  __le32 ea_size;			/* total EA length, bytes */
+  u8 no_of_acls;			/* number of ACL's (low 3 bits) */
+  u8 ix;				/* code page index (of filename), see
+					   struct code_page_data */
+  u8 namelen;				/* file name length */
+  u8 name[];				/* file name */
+  /* dnode_secno down;	  btree down pointer, if present,
+     			  follows name on next word boundary, or maybe it
+			  precedes next dirent, which is on a word boundary. */
+};
+
+
+/* B+ tree: allocation info in fnodes and anodes */
+
+/* dnodes point to fnodes which are responsible for listing the sectors
+   assigned to the file.  This is done with trees of (length,address)
+   pairs.  (Actually triples, of (length, file-address, disk-address)
+   which can represent holes.  Find out if HPFS does that.)
+   At any rate, fnodes contain a small tree; if subtrees are needed
+   they occupy essentially a full block in anodes.  A leaf-level tree node
+   has 3-word entries giving sector runs, a non-leaf node has 2-word
+   entries giving subtree pointers.  A flag in the header says which. */
+
+struct bplus_leaf_node
+{
+  __le32 file_secno;			/* first file sector in extent */
+  __le32 length;			/* length, sectors */
+  __le32 disk_secno;			/* first corresponding disk sector */
+};
+
+struct bplus_internal_node
+{
+  __le32 file_secno;			/* subtree maps sectors < this  */
+  __le32 down;				/* pointer to subtree */
+};
+
+enum {
+	BP_hbff = 1,
+	BP_fnode_parent = 0x20,
+	BP_binary_search = 0x40,
+	BP_internal = 0x80
+};
+struct bplus_header
+{
+  u8 flags;				/* bit 0 - high bit of first free entry offset
+					   bit 5 - we're pointed to by an fnode,
+					   the data btree or some ea or the
+					   main ea bootage pointer ea_secno
+					   bit 6 - suggest binary search (unused)
+					   bit 7 - 1 -> (internal) tree of anodes
+						   0 -> (leaf) list of extents */
+  u8 fill[3];
+  u8 n_free_nodes;			/* free nodes in following array */
+  u8 n_used_nodes;			/* used nodes in following array */
+  __le16 first_free;			/* offset from start of header to
+					   first free node in array */
+  union {
+	/* (internal) 2-word entries giving subtree pointers */
+	DECLARE_FLEX_ARRAY(struct bplus_internal_node, internal);
+	/* (external) 3-word entries giving sector runs */
+	DECLARE_FLEX_ARRAY(struct bplus_leaf_node, external);
+  } u;
+};
+
+static inline bool bp_internal(struct bplus_header *bp)
+{
+	return bp->flags & BP_internal;
+}
+
+static inline bool bp_fnode_parent(struct bplus_header *bp)
+{
+	return bp->flags & BP_fnode_parent;
+}
+
+/* fnode: root of allocation b+ tree, and EA's */
+
+/* Every file and every directory has one fnode, pointed to by the directory
+   entry and pointing to the file's sectors or directory's root dnode.  EA's
+   are also stored here, and there are said to be ACL's somewhere here too. */
+
+#define FNODE_MAGIC 0xf7e40aae
+
+enum {FNODE_anode = cpu_to_le16(2), FNODE_dir = cpu_to_le16(256)};
+struct fnode
+{
+  __le32 magic;				/* f7e4 0aae */
+  __le32 zero1[2];			/* read history */
+  u8 len, name[15];			/* true length, truncated name */
+  __le32 up;				/* pointer to file's directory fnode */
+  __le32 acl_size_l;
+  __le32 acl_secno;
+  __le16 acl_size_s;
+  u8 acl_anode;
+  u8 zero2;				/* history bit count */
+  __le32 ea_size_l;			/* length of disk-resident ea's */
+  __le32 ea_secno;			/* first sector of disk-resident ea's*/
+  __le16 ea_size_s;			/* length of fnode-resident ea's */
+
+  __le16 flags;				/* bit 1 set -> ea_secno is an anode */
+					/* bit 8 set -> directory.  first & only extent
+					   points to dnode. */
+  struct bplus_header btree;		/* b+ tree, 8 extents or 12 subtrees */
+  union {
+    struct bplus_leaf_node external[8];
+    struct bplus_internal_node internal[12];
+  } u;
+
+  __le32 file_size;			/* file length, bytes */
+  __le32 n_needea;			/* number of EA's with NEEDEA set */
+  u8 user_id[16];			/* unused */
+  __le16 ea_offs;			/* offset from start of fnode
+					   to first fnode-resident ea */
+  u8 dasd_limit_treshhold;
+  u8 dasd_limit_delta;
+  __le32 dasd_limit;
+  __le32 dasd_usage;
+  u8 ea[316];				/* zero or more EA's, packed together
+					   with no alignment padding.
+					   (Do not use this name, get here
+					   via fnode + ea_offs. I think.) */
+};
+
+static inline bool fnode_in_anode(struct fnode *p)
+{
+	return (p->flags & FNODE_anode) != 0;
+}
+
+static inline bool fnode_is_dir(struct fnode *p)
+{
+	return (p->flags & FNODE_dir) != 0;
+}
+
+
+/* anode: 99.44% pure allocation tree */
+
+#define ANODE_MAGIC 0x37e40aae
+
+struct anode
+{
+  __le32 magic;				/* 37e4 0aae */
+  __le32 self;				/* pointer to this anode */
+  __le32 up;				/* parent anode or fnode */
+
+  struct bplus_header btree;		/* b+tree, 40 extents or 60 subtrees */
+  union {
+    struct bplus_leaf_node external[40];
+    struct bplus_internal_node internal[60];
+  } u;
+
+  __le32 fill[3];			/* unused */
+};
+
+
+/* extended attributes.
+
+   A file's EA info is stored as a list of (name,value) pairs.  It is
+   usually in the fnode, but (if it's large) it is moved to a single
+   sector run outside the fnode, or to multiple runs with an anode tree
+   that points to them.
+
+   The value of a single EA is stored along with the name, or (if large)
+   it is moved to a single sector run, or multiple runs pointed to by an
+   anode tree, pointed to by the value field of the (name,value) pair.
+
+   Flags in the EA tell whether the value is immediate, in a single sector
+   run, or in multiple runs.  Flags in the fnode tell whether the EA list
+   is immediate, in a single run, or in multiple runs. */
+
+enum {EA_indirect = 1, EA_anode = 2, EA_needea = 128 };
+struct extended_attribute
+{
+  u8 flags;				/* bit 0 set -> value gives sector number
+					   where real value starts */
+					/* bit 1 set -> sector is an anode
+					   that points to fragmented value */
+					/* bit 7 set -> required ea */
+  u8 namelen;				/* length of name, bytes */
+  u8 valuelen_lo;			/* length of value, bytes */
+  u8 valuelen_hi;			/* length of value, bytes */
+  u8 name[];
+  /*
+    u8 name[namelen];			ascii attrib name
+    u8 nul;				terminating '\0', not counted
+    u8 value[valuelen];			value, arbitrary
+      if this.flags & 1, valuelen is 8 and the value is
+        u32 length;			real length of value, bytes
+        secno secno;			sector address where it starts
+      if this.anode, the above sector number is the root of an anode tree
+        which points to the value.
+  */
+};
+
+static inline bool ea_indirect(struct extended_attribute *ea)
+{
+	return ea->flags & EA_indirect;
+}
+
+static inline bool ea_in_anode(struct extended_attribute *ea)
+{
+	return ea->flags & EA_anode;
+}
+
+/*
+   Local Variables:
+   comment-column: 40
+   End:
+*/
diff --git a/fs/hpfs/hpfs_fn.h b/fs/hpfs/hpfs_fn.h
new file mode 100644
index 0000000000..f5a2476c47
--- /dev/null
+++ b/fs/hpfs/hpfs_fn.h
@@ -0,0 +1,379 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ *  linux/fs/hpfs/hpfs_fn.h
+ *
+ *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
+ *
+ *  function headers
+ */
+
+//#define DBG
+//#define DEBUG_LOCKS
+#ifdef pr_fmt
+#undef pr_fmt
+#endif
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/mutex.h>
+#include <linux/pagemap.h>
+#include <linux/buffer_head.h>
+#include <linux/slab.h>
+#include <linux/sched/signal.h>
+#include <linux/blkdev.h>
+#include <asm/unaligned.h>
+
+#include "hpfs.h"
+
+#define EIOERROR  EIO
+#define EFSERROR  EUCLEAN
+
+#define ANODE_ALLOC_FWD	512
+#define FNODE_ALLOC_FWD	0
+#define ALLOC_FWD_MIN	16
+#define ALLOC_FWD_MAX	128
+#define ALLOC_M		1
+#define FNODE_RD_AHEAD	16
+#define ANODE_RD_AHEAD	0
+#define DNODE_RD_AHEAD	72
+#define COUNT_RD_AHEAD	62
+
+#define FREE_DNODES_ADD	58
+#define FREE_DNODES_DEL	29
+
+#define CHKCOND(x,y) if (!(x)) printk y
+
+struct hpfs_inode_info {
+	loff_t mmu_private;
+	ino_t i_parent_dir;	/* (directories) gives fnode of parent dir */
+	unsigned i_dno;		/* (directories) root dnode */
+	unsigned i_dpos;	/* (directories) temp for readdir */
+	unsigned i_dsubdno;	/* (directories) temp for readdir */
+	unsigned i_file_sec;	/* (files) minimalist cache of alloc info */
+	unsigned i_disk_sec;	/* (files) minimalist cache of alloc info */
+	unsigned i_n_secs;	/* (files) minimalist cache of alloc info */
+	unsigned i_ea_size;	/* size of extended attributes */
+	unsigned i_ea_mode : 1;	/* file's permission is stored in ea */
+	unsigned i_ea_uid : 1;	/* file's uid is stored in ea */
+	unsigned i_ea_gid : 1;	/* file's gid is stored in ea */
+	unsigned i_dirty : 1;
+	loff_t **i_rddir_off;
+	struct inode vfs_inode;
+};
+
+struct hpfs_sb_info {
+	struct mutex hpfs_mutex;	/* global hpfs lock */
+	ino_t sb_root;			/* inode number of root dir */
+	unsigned sb_fs_size;		/* file system size, sectors */
+	unsigned sb_bitmaps;		/* sector number of bitmap list */
+	unsigned sb_dirband_start;	/* directory band start sector */
+	unsigned sb_dirband_size;	/* directory band size, dnodes */
+	unsigned sb_dmap;		/* sector number of dnode bit map */
+	unsigned sb_n_free;		/* free blocks for statfs, or -1 */
+	unsigned sb_n_free_dnodes;	/* free dnodes for statfs, or -1 */
+	kuid_t sb_uid;			/* uid from mount options */
+	kgid_t sb_gid;			/* gid from mount options */
+	umode_t sb_mode;		/* mode from mount options */
+	unsigned sb_eas : 2;		/* eas: 0-ignore, 1-ro, 2-rw */
+	unsigned sb_err : 2;		/* on errs: 0-cont, 1-ro, 2-panic */
+	unsigned sb_chk : 2;		/* checks: 0-no, 1-normal, 2-strict */
+	unsigned sb_lowercase : 1;	/* downcase filenames hackery */
+	unsigned sb_was_error : 1;	/* there was an error, set dirty flag */
+	unsigned sb_chkdsk : 2;		/* chkdsk: 0-no, 1-on errs, 2-allways */
+	unsigned char *sb_cp_table;	/* code page tables: */
+					/* 	128 bytes uppercasing table & */
+					/*	128 bytes lowercasing table */
+	__le32 *sb_bmp_dir;		/* main bitmap directory */
+	unsigned sb_c_bitmap;		/* current bitmap */
+	unsigned sb_max_fwd_alloc;	/* max forwad allocation */
+	int sb_timeshift;
+	struct rcu_head rcu;
+
+	unsigned n_hotfixes;
+	secno hotfix_from[256];
+	secno hotfix_to[256];
+};
+
+/* Four 512-byte buffers and the 2k block obtained by concatenating them */
+
+struct quad_buffer_head {
+	struct buffer_head *bh[4];
+	void *data;
+};
+
+/* The b-tree down pointer from a dir entry */
+
+static inline dnode_secno de_down_pointer (struct hpfs_dirent *de)
+{
+  CHKCOND(de->down,("HPFS: de_down_pointer: !de->down\n"));
+  return le32_to_cpu(*(__le32 *) ((void *) de + le16_to_cpu(de->length) - 4));
+}
+
+/* The first dir entry in a dnode */
+
+static inline struct hpfs_dirent *dnode_first_de (struct dnode *dnode)
+{
+  return (void *) dnode->dirent;
+}
+
+/* The end+1 of the dir entries */
+
+static inline struct hpfs_dirent *dnode_end_de (struct dnode *dnode)
+{
+  CHKCOND(le32_to_cpu(dnode->first_free)>=0x14 && le32_to_cpu(dnode->first_free)<=0xa00,("HPFS: dnode_end_de: dnode->first_free = %x\n",(unsigned)le32_to_cpu(dnode->first_free)));
+  return (void *) dnode + le32_to_cpu(dnode->first_free);
+}
+
+/* The dir entry after dir entry de */
+
+static inline struct hpfs_dirent *de_next_de (struct hpfs_dirent *de)
+{
+  CHKCOND(le16_to_cpu(de->length)>=0x20 && le16_to_cpu(de->length)<0x800,("HPFS: de_next_de: de->length = %x\n",(unsigned)le16_to_cpu(de->length)));
+  return (void *) de + le16_to_cpu(de->length);
+}
+
+static inline struct extended_attribute *fnode_ea(struct fnode *fnode)
+{
+	return (struct extended_attribute *)((char *)fnode + le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s));
+}
+
+static inline struct extended_attribute *fnode_end_ea(struct fnode *fnode)
+{
+	return (struct extended_attribute *)((char *)fnode + le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s));
+}
+
+static unsigned ea_valuelen(struct extended_attribute *ea)
+{
+	return ea->valuelen_lo + 256 * ea->valuelen_hi;
+}
+
+static inline struct extended_attribute *next_ea(struct extended_attribute *ea)
+{
+	return (struct extended_attribute *)((char *)ea + 5 + ea->namelen + ea_valuelen(ea));
+}
+
+static inline secno ea_sec(struct extended_attribute *ea)
+{
+	return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 9 + ea->namelen)));
+}
+
+static inline secno ea_len(struct extended_attribute *ea)
+{
+	return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 5 + ea->namelen)));
+}
+
+static inline char *ea_data(struct extended_attribute *ea)
+{
+	return (char *)((char *)ea + 5 + ea->namelen);
+}
+
+static inline unsigned de_size(int namelen, secno down_ptr)
+{
+	return ((0x1f + namelen + 3) & ~3) + (down_ptr ? 4 : 0);
+}
+
+static inline void copy_de(struct hpfs_dirent *dst, struct hpfs_dirent *src)
+{
+	int a;
+	int n;
+	if (!dst || !src) return;
+	a = dst->down;
+	n = dst->not_8x3;
+	memcpy((char *)dst + 2, (char *)src + 2, 28);
+	dst->down = a;
+	dst->not_8x3 = n;
+}
+
+static inline unsigned tstbits(__le32 *bmp, unsigned b, unsigned n)
+{
+	int i;
+	if ((b >= 0x4000) || (b + n - 1 >= 0x4000)) return n;
+	if (!((le32_to_cpu(bmp[(b & 0x3fff) >> 5]) >> (b & 0x1f)) & 1)) return 1;
+	for (i = 1; i < n; i++)
+		if (!((le32_to_cpu(bmp[((b+i) & 0x3fff) >> 5]) >> ((b+i) & 0x1f)) & 1))
+			return i + 1;
+	return 0;
+}
+
+/* alloc.c */
+
+int hpfs_chk_sectors(struct super_block *, secno, int, char *);
+secno hpfs_alloc_sector(struct super_block *, secno, unsigned, int);
+int hpfs_alloc_if_possible(struct super_block *, secno);
+void hpfs_free_sectors(struct super_block *, secno, unsigned);
+int hpfs_check_free_dnodes(struct super_block *, int);
+void hpfs_free_dnode(struct super_block *, secno);
+struct dnode *hpfs_alloc_dnode(struct super_block *, secno, dnode_secno *, struct quad_buffer_head *);
+struct fnode *hpfs_alloc_fnode(struct super_block *, secno, fnode_secno *, struct buffer_head **);
+struct anode *hpfs_alloc_anode(struct super_block *, secno, anode_secno *, struct buffer_head **);
+int hpfs_trim_fs(struct super_block *, u64, u64, u64, unsigned *);
+
+/* anode.c */
+
+secno hpfs_bplus_lookup(struct super_block *, struct inode *, struct bplus_header *, unsigned, struct buffer_head *);
+secno hpfs_add_sector_to_btree(struct super_block *, secno, int, unsigned);
+void hpfs_remove_btree(struct super_block *, struct bplus_header *);
+int hpfs_ea_read(struct super_block *, secno, int, unsigned, unsigned, char *);
+int hpfs_ea_write(struct super_block *, secno, int, unsigned, unsigned, const char *);
+void hpfs_ea_remove(struct super_block *, secno, int, unsigned);
+void hpfs_truncate_btree(struct super_block *, secno, int, unsigned);
+void hpfs_remove_fnode(struct super_block *, fnode_secno fno);
+
+/* buffer.c */
+
+secno hpfs_search_hotfix_map(struct super_block *s, secno sec);
+unsigned hpfs_search_hotfix_map_for_range(struct super_block *s, secno sec, unsigned n);
+void hpfs_prefetch_sectors(struct super_block *, unsigned, int);
+void *hpfs_map_sector(struct super_block *, unsigned, struct buffer_head **, int);
+void *hpfs_get_sector(struct super_block *, unsigned, struct buffer_head **);
+void *hpfs_map_4sectors(struct super_block *, unsigned, struct quad_buffer_head *, int);
+void *hpfs_get_4sectors(struct super_block *, unsigned, struct quad_buffer_head *);
+void hpfs_brelse4(struct quad_buffer_head *);
+void hpfs_mark_4buffers_dirty(struct quad_buffer_head *);
+
+/* dentry.c */
+
+extern const struct dentry_operations hpfs_dentry_operations;
+
+/* dir.c */
+
+struct dentry *hpfs_lookup(struct inode *, struct dentry *, unsigned int);
+extern const struct file_operations hpfs_dir_ops;
+
+/* dnode.c */
+
+int hpfs_add_pos(struct inode *, loff_t *);
+void hpfs_del_pos(struct inode *, loff_t *);
+struct hpfs_dirent *hpfs_add_de(struct super_block *, struct dnode *,
+				const unsigned char *, unsigned, secno);
+int hpfs_add_dirent(struct inode *, const unsigned char *, unsigned,
+		    struct hpfs_dirent *);
+int hpfs_remove_dirent(struct inode *, dnode_secno, struct hpfs_dirent *, struct quad_buffer_head *, int);
+void hpfs_count_dnodes(struct super_block *, dnode_secno, int *, int *, int *);
+dnode_secno hpfs_de_as_down_as_possible(struct super_block *, dnode_secno dno);
+struct hpfs_dirent *map_pos_dirent(struct inode *, loff_t *, struct quad_buffer_head *);
+struct hpfs_dirent *map_dirent(struct inode *, dnode_secno,
+			       const unsigned char *, unsigned, dnode_secno *,
+			       struct quad_buffer_head *);
+void hpfs_remove_dtree(struct super_block *, dnode_secno);
+struct hpfs_dirent *map_fnode_dirent(struct super_block *, fnode_secno, struct fnode *, struct quad_buffer_head *);
+
+/* ea.c */
+
+void hpfs_ea_ext_remove(struct super_block *, secno, int, unsigned);
+int hpfs_read_ea(struct super_block *, struct fnode *, char *, char *, int);
+char *hpfs_get_ea(struct super_block *, struct fnode *, char *, int *);
+void hpfs_set_ea(struct inode *, struct fnode *, const char *,
+		 const char *, int);
+
+/* file.c */
+
+int hpfs_file_fsync(struct file *, loff_t, loff_t, int);
+void hpfs_truncate(struct inode *);
+extern const struct file_operations hpfs_file_ops;
+extern const struct inode_operations hpfs_file_iops;
+extern const struct address_space_operations hpfs_aops;
+
+/* inode.c */
+
+void hpfs_init_inode(struct inode *);
+void hpfs_read_inode(struct inode *);
+void hpfs_write_inode(struct inode *);
+void hpfs_write_inode_nolock(struct inode *);
+int hpfs_setattr(struct mnt_idmap *, struct dentry *, struct iattr *);
+void hpfs_write_if_changed(struct inode *);
+void hpfs_evict_inode(struct inode *);
+
+/* map.c */
+
+__le32 *hpfs_map_dnode_bitmap(struct super_block *, struct quad_buffer_head *);
+__le32 *hpfs_map_bitmap(struct super_block *, unsigned, struct quad_buffer_head *, char *);
+void hpfs_prefetch_bitmap(struct super_block *, unsigned);
+unsigned char *hpfs_load_code_page(struct super_block *, secno);
+__le32 *hpfs_load_bitmap_directory(struct super_block *, secno bmp);
+void hpfs_load_hotfix_map(struct super_block *s, struct hpfs_spare_block *spareblock);
+struct fnode *hpfs_map_fnode(struct super_block *s, ino_t, struct buffer_head **);
+struct anode *hpfs_map_anode(struct super_block *s, anode_secno, struct buffer_head **);
+struct dnode *hpfs_map_dnode(struct super_block *s, dnode_secno, struct quad_buffer_head *);
+dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino);
+
+/* name.c */
+
+unsigned char hpfs_upcase(unsigned char *, unsigned char);
+int hpfs_chk_name(const unsigned char *, unsigned *);
+unsigned char *hpfs_translate_name(struct super_block *, unsigned char *, unsigned, int, int);
+int hpfs_compare_names(struct super_block *, const unsigned char *, unsigned,
+		       const unsigned char *, unsigned, int);
+int hpfs_is_name_long(const unsigned char *, unsigned);
+void hpfs_adjust_length(const unsigned char *, unsigned *);
+
+/* namei.c */
+
+extern const struct inode_operations hpfs_dir_iops;
+extern const struct address_space_operations hpfs_symlink_aops;
+
+static inline struct hpfs_inode_info *hpfs_i(struct inode *inode)
+{
+	return container_of(inode, struct hpfs_inode_info, vfs_inode);
+}
+
+static inline struct hpfs_sb_info *hpfs_sb(struct super_block *sb)
+{
+	return sb->s_fs_info;
+}
+
+/* super.c */
+
+__printf(2, 3)
+void hpfs_error(struct super_block *, const char *, ...);
+int hpfs_stop_cycles(struct super_block *, int, int *, int *, char *);
+unsigned hpfs_get_free_dnodes(struct super_block *);
+long hpfs_ioctl(struct file *file, unsigned cmd, unsigned long arg);
+
+/*
+ * local time (HPFS) to GMT (Unix)
+ */
+
+static inline time64_t local_to_gmt(struct super_block *s, time64_t t)
+{
+	extern struct timezone sys_tz;
+	return t + sys_tz.tz_minuteswest * 60 + hpfs_sb(s)->sb_timeshift;
+}
+
+static inline time32_t gmt_to_local(struct super_block *s, time64_t t)
+{
+	extern struct timezone sys_tz;
+	return t - sys_tz.tz_minuteswest * 60 - hpfs_sb(s)->sb_timeshift;
+}
+
+static inline time32_t local_get_seconds(struct super_block *s)
+{
+	return gmt_to_local(s, ktime_get_real_seconds());
+}
+
+/*
+ * Locking:
+ *
+ * hpfs_lock() locks the whole filesystem. It must be taken
+ * on any method called by the VFS.
+ *
+ * We don't do any per-file locking anymore, it is hard to
+ * review and HPFS is not performance-sensitive anyway.
+ */
+static inline void hpfs_lock(struct super_block *s)
+{
+	struct hpfs_sb_info *sbi = hpfs_sb(s);
+	mutex_lock(&sbi->hpfs_mutex);
+}
+
+static inline void hpfs_unlock(struct super_block *s)
+{
+	struct hpfs_sb_info *sbi = hpfs_sb(s);
+	mutex_unlock(&sbi->hpfs_mutex);
+}
+
+static inline void hpfs_lock_assert(struct super_block *s)
+{
+	struct hpfs_sb_info *sbi = hpfs_sb(s);
+	WARN_ON(!mutex_is_locked(&sbi->hpfs_mutex));
+}
diff --git a/fs/hpfs/inode.c b/fs/hpfs/inode.c
new file mode 100644
index 0000000000..479166378b
--- /dev/null
+++ b/fs/hpfs/inode.c
@@ -0,0 +1,318 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/hpfs/inode.c
+ *
+ *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
+ *
+ *  inode VFS functions
+ */
+
+#include <linux/slab.h>
+#include <linux/user_namespace.h>
+#include "hpfs_fn.h"
+
+void hpfs_init_inode(struct inode *i)
+{
+	struct super_block *sb = i->i_sb;
+	struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
+
+	i->i_uid = hpfs_sb(sb)->sb_uid;
+	i->i_gid = hpfs_sb(sb)->sb_gid;
+	i->i_mode = hpfs_sb(sb)->sb_mode;
+	i->i_size = -1;
+	i->i_blocks = -1;
+	
+	hpfs_inode->i_dno = 0;
+	hpfs_inode->i_n_secs = 0;
+	hpfs_inode->i_file_sec = 0;
+	hpfs_inode->i_disk_sec = 0;
+	hpfs_inode->i_dpos = 0;
+	hpfs_inode->i_dsubdno = 0;
+	hpfs_inode->i_ea_mode = 0;
+	hpfs_inode->i_ea_uid = 0;
+	hpfs_inode->i_ea_gid = 0;
+	hpfs_inode->i_ea_size = 0;
+
+	hpfs_inode->i_rddir_off = NULL;
+	hpfs_inode->i_dirty = 0;
+
+	inode_set_ctime(i, 0, 0);
+	i->i_mtime.tv_sec = i->i_mtime.tv_nsec = 0;
+	i->i_atime.tv_sec = i->i_atime.tv_nsec = 0;
+}
+
+void hpfs_read_inode(struct inode *i)
+{
+	struct buffer_head *bh;
+	struct fnode *fnode;
+	struct super_block *sb = i->i_sb;
+	struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
+	void *ea;
+	int ea_size;
+
+	if (!(fnode = hpfs_map_fnode(sb, i->i_ino, &bh))) {
+		/*i->i_mode |= S_IFREG;
+		i->i_mode &= ~0111;
+		i->i_op = &hpfs_file_iops;
+		i->i_fop = &hpfs_file_ops;
+		clear_nlink(i);*/
+		make_bad_inode(i);
+		return;
+	}
+	if (hpfs_sb(i->i_sb)->sb_eas) {
+		if ((ea = hpfs_get_ea(i->i_sb, fnode, "UID", &ea_size))) {
+			if (ea_size == 2) {
+				i_uid_write(i, le16_to_cpu(*(__le16*)ea));
+				hpfs_inode->i_ea_uid = 1;
+			}
+			kfree(ea);
+		}
+		if ((ea = hpfs_get_ea(i->i_sb, fnode, "GID", &ea_size))) {
+			if (ea_size == 2) {
+				i_gid_write(i, le16_to_cpu(*(__le16*)ea));
+				hpfs_inode->i_ea_gid = 1;
+			}
+			kfree(ea);
+		}
+		if ((ea = hpfs_get_ea(i->i_sb, fnode, "SYMLINK", &ea_size))) {
+			kfree(ea);
+			i->i_mode = S_IFLNK | 0777;
+			i->i_op = &page_symlink_inode_operations;
+			inode_nohighmem(i);
+			i->i_data.a_ops = &hpfs_symlink_aops;
+			set_nlink(i, 1);
+			i->i_size = ea_size;
+			i->i_blocks = 1;
+			brelse(bh);
+			return;
+		}
+		if ((ea = hpfs_get_ea(i->i_sb, fnode, "MODE", &ea_size))) {
+			int rdev = 0;
+			umode_t mode = hpfs_sb(sb)->sb_mode;
+			if (ea_size == 2) {
+				mode = le16_to_cpu(*(__le16*)ea);
+				hpfs_inode->i_ea_mode = 1;
+			}
+			kfree(ea);
+			i->i_mode = mode;
+			if (S_ISBLK(mode) || S_ISCHR(mode)) {
+				if ((ea = hpfs_get_ea(i->i_sb, fnode, "DEV", &ea_size))) {
+					if (ea_size == 4)
+						rdev = le32_to_cpu(*(__le32*)ea);
+					kfree(ea);
+				}
+			}
+			if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
+				brelse(bh);
+				set_nlink(i, 1);
+				i->i_size = 0;
+				i->i_blocks = 1;
+				init_special_inode(i, mode,
+					new_decode_dev(rdev));
+				return;
+			}
+		}
+	}
+	if (fnode_is_dir(fnode)) {
+		int n_dnodes, n_subdirs;
+		i->i_mode |= S_IFDIR;
+		i->i_op = &hpfs_dir_iops;
+		i->i_fop = &hpfs_dir_ops;
+		hpfs_inode->i_parent_dir = le32_to_cpu(fnode->up);
+		hpfs_inode->i_dno = le32_to_cpu(fnode->u.external[0].disk_secno);
+		if (hpfs_sb(sb)->sb_chk >= 2) {
+			struct buffer_head *bh0;
+			if (hpfs_map_fnode(sb, hpfs_inode->i_parent_dir, &bh0)) brelse(bh0);
+		}
+		n_dnodes = 0; n_subdirs = 0;
+		hpfs_count_dnodes(i->i_sb, hpfs_inode->i_dno, &n_dnodes, &n_subdirs, NULL);
+		i->i_blocks = 4 * n_dnodes;
+		i->i_size = 2048 * n_dnodes;
+		set_nlink(i, 2 + n_subdirs);
+	} else {
+		i->i_mode |= S_IFREG;
+		if (!hpfs_inode->i_ea_mode) i->i_mode &= ~0111;
+		i->i_op = &hpfs_file_iops;
+		i->i_fop = &hpfs_file_ops;
+		set_nlink(i, 1);
+		i->i_size = le32_to_cpu(fnode->file_size);
+		i->i_blocks = ((i->i_size + 511) >> 9) + 1;
+		i->i_data.a_ops = &hpfs_aops;
+		hpfs_i(i)->mmu_private = i->i_size;
+	}
+	brelse(bh);
+}
+
+static void hpfs_write_inode_ea(struct inode *i, struct fnode *fnode)
+{
+	struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
+	/*if (le32_to_cpu(fnode->acl_size_l) || le16_to_cpu(fnode->acl_size_s)) {
+		   Some unknown structures like ACL may be in fnode,
+		   we'd better not overwrite them
+		hpfs_error(i->i_sb, "fnode %08x has some unknown HPFS386 structures", i->i_ino);
+	} else*/ if (hpfs_sb(i->i_sb)->sb_eas >= 2) {
+		__le32 ea;
+		if (!uid_eq(i->i_uid, hpfs_sb(i->i_sb)->sb_uid) || hpfs_inode->i_ea_uid) {
+			ea = cpu_to_le32(i_uid_read(i));
+			hpfs_set_ea(i, fnode, "UID", (char*)&ea, 2);
+			hpfs_inode->i_ea_uid = 1;
+		}
+		if (!gid_eq(i->i_gid, hpfs_sb(i->i_sb)->sb_gid) || hpfs_inode->i_ea_gid) {
+			ea = cpu_to_le32(i_gid_read(i));
+			hpfs_set_ea(i, fnode, "GID", (char *)&ea, 2);
+			hpfs_inode->i_ea_gid = 1;
+		}
+		if (!S_ISLNK(i->i_mode))
+			if ((i->i_mode != ((hpfs_sb(i->i_sb)->sb_mode & ~(S_ISDIR(i->i_mode) ? 0 : 0111))
+			  | (S_ISDIR(i->i_mode) ? S_IFDIR : S_IFREG))
+			  && i->i_mode != ((hpfs_sb(i->i_sb)->sb_mode & ~(S_ISDIR(i->i_mode) ? 0222 : 0333))
+			  | (S_ISDIR(i->i_mode) ? S_IFDIR : S_IFREG))) || hpfs_inode->i_ea_mode) {
+				ea = cpu_to_le32(i->i_mode);
+				/* sick, but legal */
+				hpfs_set_ea(i, fnode, "MODE", (char *)&ea, 2);
+				hpfs_inode->i_ea_mode = 1;
+			}
+		if (S_ISBLK(i->i_mode) || S_ISCHR(i->i_mode)) {
+			ea = cpu_to_le32(new_encode_dev(i->i_rdev));
+			hpfs_set_ea(i, fnode, "DEV", (char *)&ea, 4);
+		}
+	}
+}
+
+void hpfs_write_inode(struct inode *i)
+{
+	struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
+	struct inode *parent;
+	if (i->i_ino == hpfs_sb(i->i_sb)->sb_root) return;
+	if (hpfs_inode->i_rddir_off && !atomic_read(&i->i_count)) {
+		if (*hpfs_inode->i_rddir_off)
+			pr_err("write_inode: some position still there\n");
+		kfree(hpfs_inode->i_rddir_off);
+		hpfs_inode->i_rddir_off = NULL;
+	}
+	if (!i->i_nlink) {
+		return;
+	}
+	parent = iget_locked(i->i_sb, hpfs_inode->i_parent_dir);
+	if (parent) {
+		hpfs_inode->i_dirty = 0;
+		if (parent->i_state & I_NEW) {
+			hpfs_init_inode(parent);
+			hpfs_read_inode(parent);
+			unlock_new_inode(parent);
+		}
+		hpfs_write_inode_nolock(i);
+		iput(parent);
+	}
+}
+
+void hpfs_write_inode_nolock(struct inode *i)
+{
+	struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
+	struct buffer_head *bh;
+	struct fnode *fnode;
+	struct quad_buffer_head qbh;
+	struct hpfs_dirent *de;
+	if (i->i_ino == hpfs_sb(i->i_sb)->sb_root) return;
+	if (!(fnode = hpfs_map_fnode(i->i_sb, i->i_ino, &bh))) return;
+	if (i->i_ino != hpfs_sb(i->i_sb)->sb_root && i->i_nlink) {
+		if (!(de = map_fnode_dirent(i->i_sb, i->i_ino, fnode, &qbh))) {
+			brelse(bh);
+			return;
+		}
+	} else de = NULL;
+	if (S_ISREG(i->i_mode)) {
+		fnode->file_size = cpu_to_le32(i->i_size);
+		if (de) de->file_size = cpu_to_le32(i->i_size);
+	} else if (S_ISDIR(i->i_mode)) {
+		fnode->file_size = cpu_to_le32(0);
+		if (de) de->file_size = cpu_to_le32(0);
+	}
+	hpfs_write_inode_ea(i, fnode);
+	if (de) {
+		de->write_date = cpu_to_le32(gmt_to_local(i->i_sb, i->i_mtime.tv_sec));
+		de->read_date = cpu_to_le32(gmt_to_local(i->i_sb, i->i_atime.tv_sec));
+		de->creation_date = cpu_to_le32(gmt_to_local(i->i_sb, inode_get_ctime(i).tv_sec));
+		de->read_only = !(i->i_mode & 0222);
+		de->ea_size = cpu_to_le32(hpfs_inode->i_ea_size);
+		hpfs_mark_4buffers_dirty(&qbh);
+		hpfs_brelse4(&qbh);
+	}
+	if (S_ISDIR(i->i_mode)) {
+		if ((de = map_dirent(i, hpfs_inode->i_dno, "\001\001", 2, NULL, &qbh))) {
+			de->write_date = cpu_to_le32(gmt_to_local(i->i_sb, i->i_mtime.tv_sec));
+			de->read_date = cpu_to_le32(gmt_to_local(i->i_sb, i->i_atime.tv_sec));
+			de->creation_date = cpu_to_le32(gmt_to_local(i->i_sb, inode_get_ctime(i).tv_sec));
+			de->read_only = !(i->i_mode & 0222);
+			de->ea_size = cpu_to_le32(/*hpfs_inode->i_ea_size*/0);
+			de->file_size = cpu_to_le32(0);
+			hpfs_mark_4buffers_dirty(&qbh);
+			hpfs_brelse4(&qbh);
+		} else
+			hpfs_error(i->i_sb,
+				"directory %08lx doesn't have '.' entry",
+				(unsigned long)i->i_ino);
+	}
+	mark_buffer_dirty(bh);
+	brelse(bh);
+}
+
+int hpfs_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
+		 struct iattr *attr)
+{
+	struct inode *inode = d_inode(dentry);
+	int error = -EINVAL;
+
+	hpfs_lock(inode->i_sb);
+	if (inode->i_ino == hpfs_sb(inode->i_sb)->sb_root)
+		goto out_unlock;
+	if ((attr->ia_valid & ATTR_UID) &&
+	    from_kuid(&init_user_ns, attr->ia_uid) >= 0x10000)
+		goto out_unlock;
+	if ((attr->ia_valid & ATTR_GID) &&
+	    from_kgid(&init_user_ns, attr->ia_gid) >= 0x10000)
+		goto out_unlock;
+	if ((attr->ia_valid & ATTR_SIZE) && attr->ia_size > inode->i_size)
+		goto out_unlock;
+
+	error = setattr_prepare(&nop_mnt_idmap, dentry, attr);
+	if (error)
+		goto out_unlock;
+
+	if ((attr->ia_valid & ATTR_SIZE) &&
+	    attr->ia_size != i_size_read(inode)) {
+		error = inode_newsize_ok(inode, attr->ia_size);
+		if (error)
+			goto out_unlock;
+
+		truncate_setsize(inode, attr->ia_size);
+		hpfs_truncate(inode);
+	}
+
+	setattr_copy(&nop_mnt_idmap, inode, attr);
+
+	hpfs_write_inode(inode);
+
+ out_unlock:
+	hpfs_unlock(inode->i_sb);
+	return error;
+}
+
+void hpfs_write_if_changed(struct inode *inode)
+{
+	struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
+
+	if (hpfs_inode->i_dirty)
+		hpfs_write_inode(inode);
+}
+
+void hpfs_evict_inode(struct inode *inode)
+{
+	truncate_inode_pages_final(&inode->i_data);
+	clear_inode(inode);
+	if (!inode->i_nlink) {
+		hpfs_lock(inode->i_sb);
+		hpfs_remove_fnode(inode->i_sb, inode->i_ino);
+		hpfs_unlock(inode->i_sb);
+	}
+}
diff --git a/fs/hpfs/map.c b/fs/hpfs/map.c
new file mode 100644
index 0000000000..ecd9fccd16
--- /dev/null
+++ b/fs/hpfs/map.c
@@ -0,0 +1,335 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/hpfs/map.c
+ *
+ *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
+ *
+ *  mapping structures to memory with some minimal checks
+ */
+
+#include "hpfs_fn.h"
+
+__le32 *hpfs_map_dnode_bitmap(struct super_block *s, struct quad_buffer_head *qbh)
+{
+	return hpfs_map_4sectors(s, hpfs_sb(s)->sb_dmap, qbh, 0);
+}
+
+__le32 *hpfs_map_bitmap(struct super_block *s, unsigned bmp_block,
+			 struct quad_buffer_head *qbh, char *id)
+{
+	secno sec;
+	__le32 *ret;
+	unsigned n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14;
+	if (hpfs_sb(s)->sb_chk) if (bmp_block >= n_bands) {
+		hpfs_error(s, "hpfs_map_bitmap called with bad parameter: %08x at %s", bmp_block, id);
+		return NULL;
+	}
+	sec = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block]);
+	if (!sec || sec > hpfs_sb(s)->sb_fs_size-4) {
+		hpfs_error(s, "invalid bitmap block pointer %08x -> %08x at %s", bmp_block, sec, id);
+		return NULL;
+	}
+	ret = hpfs_map_4sectors(s, sec, qbh, 4);
+	if (ret) hpfs_prefetch_bitmap(s, bmp_block + 1);
+	return ret;
+}
+
+void hpfs_prefetch_bitmap(struct super_block *s, unsigned bmp_block)
+{
+	unsigned to_prefetch, next_prefetch;
+	unsigned n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14;
+	if (unlikely(bmp_block >= n_bands))
+		return;
+	to_prefetch = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block]);
+	if (unlikely(bmp_block + 1 >= n_bands))
+		next_prefetch = 0;
+	else
+		next_prefetch = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block + 1]);
+	hpfs_prefetch_sectors(s, to_prefetch, 4 + 4 * (to_prefetch + 4 == next_prefetch));
+}
+
+/*
+ * Load first code page into kernel memory, return pointer to 256-byte array,
+ * first 128 bytes are uppercasing table for chars 128-255, next 128 bytes are
+ * lowercasing table
+ */
+
+unsigned char *hpfs_load_code_page(struct super_block *s, secno cps)
+{
+	struct buffer_head *bh;
+	secno cpds;
+	unsigned cpi;
+	unsigned char *ptr;
+	unsigned char *cp_table;
+	int i;
+	struct code_page_data *cpd;
+	struct code_page_directory *cp = hpfs_map_sector(s, cps, &bh, 0);
+	if (!cp) return NULL;
+	if (le32_to_cpu(cp->magic) != CP_DIR_MAGIC) {
+		pr_err("Code page directory magic doesn't match (magic = %08x)\n",
+			le32_to_cpu(cp->magic));
+		brelse(bh);
+		return NULL;
+	}
+	if (!le32_to_cpu(cp->n_code_pages)) {
+		pr_err("n_code_pages == 0\n");
+		brelse(bh);
+		return NULL;
+	}
+	cpds = le32_to_cpu(cp->array[0].code_page_data);
+	cpi = le16_to_cpu(cp->array[0].index);
+	brelse(bh);
+
+	if (cpi >= 3) {
+		pr_err("Code page index out of array\n");
+		return NULL;
+	}
+	
+	if (!(cpd = hpfs_map_sector(s, cpds, &bh, 0))) return NULL;
+	if (le16_to_cpu(cpd->offs[cpi]) > 0x178) {
+		pr_err("Code page index out of sector\n");
+		brelse(bh);
+		return NULL;
+	}
+	ptr = (unsigned char *)cpd + le16_to_cpu(cpd->offs[cpi]) + 6;
+	if (!(cp_table = kmalloc(256, GFP_KERNEL))) {
+		pr_err("out of memory for code page table\n");
+		brelse(bh);
+		return NULL;
+	}
+	memcpy(cp_table, ptr, 128);
+	brelse(bh);
+
+	/* Try to build lowercasing table from uppercasing one */
+
+	for (i=128; i<256; i++) cp_table[i]=i;
+	for (i=128; i<256; i++) if (cp_table[i-128]!=i && cp_table[i-128]>=128)
+		cp_table[cp_table[i-128]] = i;
+	
+	return cp_table;
+}
+
+__le32 *hpfs_load_bitmap_directory(struct super_block *s, secno bmp)
+{
+	struct buffer_head *bh;
+	int n = (hpfs_sb(s)->sb_fs_size + 0x200000 - 1) >> 21;
+	int i;
+	__le32 *b;
+	if (!(b = kmalloc_array(n, 512, GFP_KERNEL))) {
+		pr_err("can't allocate memory for bitmap directory\n");
+		return NULL;
+	}	
+	for (i=0;i<n;i++) {
+		__le32 *d = hpfs_map_sector(s, bmp+i, &bh, n - i - 1);
+		if (!d) {
+			kfree(b);
+			return NULL;
+		}
+		memcpy((char *)b + 512 * i, d, 512);
+		brelse(bh);
+	}
+	return b;
+}
+
+void hpfs_load_hotfix_map(struct super_block *s, struct hpfs_spare_block *spareblock)
+{
+	struct quad_buffer_head qbh;
+	__le32 *directory;
+	u32 n_hotfixes, n_used_hotfixes;
+	unsigned i;
+
+	n_hotfixes = le32_to_cpu(spareblock->n_spares);
+	n_used_hotfixes = le32_to_cpu(spareblock->n_spares_used);
+
+	if (n_hotfixes > 256 || n_used_hotfixes > n_hotfixes) {
+		hpfs_error(s, "invalid number of hotfixes: %u, used: %u", n_hotfixes, n_used_hotfixes);
+		return;
+	}
+	if (!(directory = hpfs_map_4sectors(s, le32_to_cpu(spareblock->hotfix_map), &qbh, 0))) {
+		hpfs_error(s, "can't load hotfix map");
+		return;
+	}
+	for (i = 0; i < n_used_hotfixes; i++) {
+		hpfs_sb(s)->hotfix_from[i] = le32_to_cpu(directory[i]);
+		hpfs_sb(s)->hotfix_to[i] = le32_to_cpu(directory[n_hotfixes + i]);
+	}
+	hpfs_sb(s)->n_hotfixes = n_used_hotfixes;
+	hpfs_brelse4(&qbh);
+}
+
+/*
+ * Load fnode to memory
+ */
+
+struct fnode *hpfs_map_fnode(struct super_block *s, ino_t ino, struct buffer_head **bhp)
+{
+	struct fnode *fnode;
+	if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, ino, 1, "fnode")) {
+		return NULL;
+	}
+	if ((fnode = hpfs_map_sector(s, ino, bhp, FNODE_RD_AHEAD))) {
+		if (hpfs_sb(s)->sb_chk) {
+			struct extended_attribute *ea;
+			struct extended_attribute *ea_end;
+			if (le32_to_cpu(fnode->magic) != FNODE_MAGIC) {
+				hpfs_error(s, "bad magic on fnode %08lx",
+					(unsigned long)ino);
+				goto bail;
+			}
+			if (!fnode_is_dir(fnode)) {
+				if ((unsigned)fnode->btree.n_used_nodes + (unsigned)fnode->btree.n_free_nodes !=
+				    (bp_internal(&fnode->btree) ? 12 : 8)) {
+					hpfs_error(s,
+					   "bad number of nodes in fnode %08lx",
+					    (unsigned long)ino);
+					goto bail;
+				}
+				if (le16_to_cpu(fnode->btree.first_free) !=
+				    8 + fnode->btree.n_used_nodes * (bp_internal(&fnode->btree) ? 8 : 12)) {
+					hpfs_error(s,
+					    "bad first_free pointer in fnode %08lx",
+					    (unsigned long)ino);
+					goto bail;
+				}
+			}
+			if (le16_to_cpu(fnode->ea_size_s) && (le16_to_cpu(fnode->ea_offs) < 0xc4 ||
+			   le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s) > 0x200)) {
+				hpfs_error(s,
+					"bad EA info in fnode %08lx: ea_offs == %04x ea_size_s == %04x",
+					(unsigned long)ino,
+					le16_to_cpu(fnode->ea_offs), le16_to_cpu(fnode->ea_size_s));
+				goto bail;
+			}
+			ea = fnode_ea(fnode);
+			ea_end = fnode_end_ea(fnode);
+			while (ea != ea_end) {
+				if (ea > ea_end) {
+					hpfs_error(s, "bad EA in fnode %08lx",
+						(unsigned long)ino);
+					goto bail;
+				}
+				ea = next_ea(ea);
+			}
+		}
+	}
+	return fnode;
+	bail:
+	brelse(*bhp);
+	return NULL;
+}
+
+struct anode *hpfs_map_anode(struct super_block *s, anode_secno ano, struct buffer_head **bhp)
+{
+	struct anode *anode;
+	if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, ano, 1, "anode")) return NULL;
+	if ((anode = hpfs_map_sector(s, ano, bhp, ANODE_RD_AHEAD)))
+		if (hpfs_sb(s)->sb_chk) {
+			if (le32_to_cpu(anode->magic) != ANODE_MAGIC) {
+				hpfs_error(s, "bad magic on anode %08x", ano);
+				goto bail;
+			}
+			if (le32_to_cpu(anode->self) != ano) {
+				hpfs_error(s, "self pointer invalid on anode %08x", ano);
+				goto bail;
+			}
+			if ((unsigned)anode->btree.n_used_nodes + (unsigned)anode->btree.n_free_nodes !=
+			    (bp_internal(&anode->btree) ? 60 : 40)) {
+				hpfs_error(s, "bad number of nodes in anode %08x", ano);
+				goto bail;
+			}
+			if (le16_to_cpu(anode->btree.first_free) !=
+			    8 + anode->btree.n_used_nodes * (bp_internal(&anode->btree) ? 8 : 12)) {
+				hpfs_error(s, "bad first_free pointer in anode %08x", ano);
+				goto bail;
+			}
+		}
+	return anode;
+	bail:
+	brelse(*bhp);
+	return NULL;
+}
+
+/*
+ * Load dnode to memory and do some checks
+ */
+
+struct dnode *hpfs_map_dnode(struct super_block *s, unsigned secno,
+			     struct quad_buffer_head *qbh)
+{
+	struct dnode *dnode;
+	if (hpfs_sb(s)->sb_chk) {
+		if (hpfs_chk_sectors(s, secno, 4, "dnode")) return NULL;
+		if (secno & 3) {
+			hpfs_error(s, "dnode %08x not byte-aligned", secno);
+			return NULL;
+		}	
+	}
+	if ((dnode = hpfs_map_4sectors(s, secno, qbh, DNODE_RD_AHEAD)))
+		if (hpfs_sb(s)->sb_chk) {
+			unsigned p, pp = 0;
+			unsigned char *d = (unsigned char *)dnode;
+			int b = 0;
+			if (le32_to_cpu(dnode->magic) != DNODE_MAGIC) {
+				hpfs_error(s, "bad magic on dnode %08x", secno);
+				goto bail;
+			}
+			if (le32_to_cpu(dnode->self) != secno)
+				hpfs_error(s, "bad self pointer on dnode %08x self = %08x", secno, le32_to_cpu(dnode->self));
+			/* Check dirents - bad dirents would cause infinite
+			   loops or shooting to memory */
+			if (le32_to_cpu(dnode->first_free) > 2048) {
+				hpfs_error(s, "dnode %08x has first_free == %08x", secno, le32_to_cpu(dnode->first_free));
+				goto bail;
+			}
+			for (p = 20; p < le32_to_cpu(dnode->first_free); p += d[p] + (d[p+1] << 8)) {
+				struct hpfs_dirent *de = (struct hpfs_dirent *)((char *)dnode + p);
+				if (le16_to_cpu(de->length) > 292 || (le16_to_cpu(de->length) < 32) || (le16_to_cpu(de->length) & 3) || p + le16_to_cpu(de->length) > 2048) {
+					hpfs_error(s, "bad dirent size in dnode %08x, dirent %03x, last %03x", secno, p, pp);
+					goto bail;
+				}
+				if (((31 + de->namelen + de->down*4 + 3) & ~3) != le16_to_cpu(de->length)) {
+					if (((31 + de->namelen + de->down*4 + 3) & ~3) < le16_to_cpu(de->length) && s->s_flags & SB_RDONLY) goto ok;
+					hpfs_error(s, "namelen does not match dirent size in dnode %08x, dirent %03x, last %03x", secno, p, pp);
+					goto bail;
+				}
+				ok:
+				if (hpfs_sb(s)->sb_chk >= 2) b |= 1 << de->down;
+				if (de->down) if (de_down_pointer(de) < 0x10) {
+					hpfs_error(s, "bad down pointer in dnode %08x, dirent %03x, last %03x", secno, p, pp);
+					goto bail;
+				}
+				pp = p;
+				
+			}
+			if (p != le32_to_cpu(dnode->first_free)) {
+				hpfs_error(s, "size on last dirent does not match first_free; dnode %08x", secno);
+				goto bail;
+			}
+			if (d[pp + 30] != 1 || d[pp + 31] != 255) {
+				hpfs_error(s, "dnode %08x does not end with \\377 entry", secno);
+				goto bail;
+			}
+			if (b == 3)
+				pr_err("unbalanced dnode tree, dnode %08x; see hpfs.txt 4 more info\n",
+					secno);
+		}
+	return dnode;
+	bail:
+	hpfs_brelse4(qbh);
+	return NULL;
+}
+
+dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino)
+{
+	struct buffer_head *bh;
+	struct fnode *fnode;
+	dnode_secno dno;
+
+	fnode = hpfs_map_fnode(s, ino, &bh);
+	if (!fnode)
+		return 0;
+
+	dno = le32_to_cpu(fnode->u.external[0].disk_secno);
+	brelse(bh);
+	return dno;
+}
diff --git a/fs/hpfs/name.c b/fs/hpfs/name.c
new file mode 100644
index 0000000000..ef7ba77f36
--- /dev/null
+++ b/fs/hpfs/name.c
@@ -0,0 +1,114 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/hpfs/name.c
+ *
+ *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
+ *
+ *  operations with filenames
+ */
+
+#include "hpfs_fn.h"
+
+static inline int not_allowed_char(unsigned char c)
+{
+	return c<' ' || c=='"' || c=='*' || c=='/' || c==':' || c=='<' ||
+	      c=='>' || c=='?' || c=='\\' || c=='|';
+}
+
+static inline int no_dos_char(unsigned char c)
+{	/* Characters that are allowed in HPFS but not in DOS */
+	return c=='+' || c==',' || c==';' || c=='=' || c=='[' || c==']';
+}
+
+static inline unsigned char upcase(unsigned char *dir, unsigned char a)
+{
+	if (a<128 || a==255) return a>='a' && a<='z' ? a - 0x20 : a;
+	if (!dir) return a;
+	return dir[a-128];
+}
+
+unsigned char hpfs_upcase(unsigned char *dir, unsigned char a)
+{
+	return upcase(dir, a);
+}
+
+static inline unsigned char locase(unsigned char *dir, unsigned char a)
+{
+	if (a<128 || a==255) return a>='A' && a<='Z' ? a + 0x20 : a;
+	if (!dir) return a;
+	return dir[a];
+}
+
+int hpfs_chk_name(const unsigned char *name, unsigned *len)
+{
+	int i;
+	if (*len > 254) return -ENAMETOOLONG;
+	hpfs_adjust_length(name, len);
+	if (!*len) return -EINVAL;
+	for (i = 0; i < *len; i++) if (not_allowed_char(name[i])) return -EINVAL;
+	if (*len == 1) if (name[0] == '.') return -EINVAL;
+	if (*len == 2) if (name[0] == '.' && name[1] == '.') return -EINVAL;
+	return 0;
+}
+
+unsigned char *hpfs_translate_name(struct super_block *s, unsigned char *from,
+			  unsigned len, int lc, int lng)
+{
+	unsigned char *to;
+	int i;
+	if (hpfs_sb(s)->sb_chk >= 2) if (hpfs_is_name_long(from, len) != lng) {
+		pr_err("Long name flag mismatch - name ");
+		for (i = 0; i < len; i++)
+			pr_cont("%c", from[i]);
+		pr_cont(" misidentified as %s.\n", lng ? "short" : "long");
+		pr_err("It's nothing serious. It could happen because of bug in OS/2.\nSet checks=normal to disable this message.\n");
+	}
+	if (!lc) return from;
+	if (!(to = kmalloc(len, GFP_KERNEL))) {
+		pr_err("can't allocate memory for name conversion buffer\n");
+		return from;
+	}
+	for (i = 0; i < len; i++) to[i] = locase(hpfs_sb(s)->sb_cp_table,from[i]);
+	return to;
+}
+
+int hpfs_compare_names(struct super_block *s,
+		       const unsigned char *n1, unsigned l1,
+		       const unsigned char *n2, unsigned l2, int last)
+{
+	unsigned l = l1 < l2 ? l1 : l2;
+	unsigned i;
+	if (last) return -1;
+	for (i = 0; i < l; i++) {
+		unsigned char c1 = upcase(hpfs_sb(s)->sb_cp_table,n1[i]);
+		unsigned char c2 = upcase(hpfs_sb(s)->sb_cp_table,n2[i]);
+		if (c1 < c2) return -1;
+		if (c1 > c2) return 1;
+	}
+	if (l1 < l2) return -1;
+	if (l1 > l2) return 1;
+	return 0;
+}
+
+int hpfs_is_name_long(const unsigned char *name, unsigned len)
+{
+	int i,j;
+	for (i = 0; i < len && name[i] != '.'; i++)
+		if (no_dos_char(name[i])) return 1;
+	if (!i || i > 8) return 1;
+	if (i == len) return 0;
+	for (j = i + 1; j < len; j++)
+		if (name[j] == '.' || no_dos_char(name[i])) return 1;
+	return j - i > 4;
+}
+
+/* OS/2 clears dots and spaces at the end of file name, so we have to */
+
+void hpfs_adjust_length(const unsigned char *name, unsigned *len)
+{
+	if (!*len) return;
+	if (*len == 1 && name[0] == '.') return;
+	if (*len == 2 && name[0] == '.' && name[1] == '.') return;
+	while (*len && (name[*len - 1] == '.' || name[*len - 1] == ' '))
+		(*len)--;
+}
diff --git a/fs/hpfs/namei.c b/fs/hpfs/namei.c
new file mode 100644
index 0000000000..f4eb8d6f59
--- /dev/null
+++ b/fs/hpfs/namei.c
@@ -0,0 +1,624 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/hpfs/namei.c
+ *
+ *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
+ *
+ *  adding & removing files & directories
+ */
+#include <linux/sched.h>
+#include "hpfs_fn.h"
+
+static void hpfs_update_directory_times(struct inode *dir)
+{
+	time64_t t = local_to_gmt(dir->i_sb, local_get_seconds(dir->i_sb));
+	if (t == dir->i_mtime.tv_sec &&
+	    t == inode_get_ctime(dir).tv_sec)
+		return;
+	dir->i_mtime = inode_set_ctime(dir, t, 0);
+	hpfs_write_inode_nolock(dir);
+}
+
+static int hpfs_mkdir(struct mnt_idmap *idmap, struct inode *dir,
+		      struct dentry *dentry, umode_t mode)
+{
+	const unsigned char *name = dentry->d_name.name;
+	unsigned len = dentry->d_name.len;
+	struct quad_buffer_head qbh0;
+	struct buffer_head *bh;
+	struct hpfs_dirent *de;
+	struct fnode *fnode;
+	struct dnode *dnode;
+	struct inode *result;
+	fnode_secno fno;
+	dnode_secno dno;
+	int r;
+	struct hpfs_dirent dee;
+	int err;
+	if ((err = hpfs_chk_name(name, &len))) return err==-ENOENT ? -EINVAL : err;
+	hpfs_lock(dir->i_sb);
+	err = -ENOSPC;
+	fnode = hpfs_alloc_fnode(dir->i_sb, hpfs_i(dir)->i_dno, &fno, &bh);
+	if (!fnode)
+		goto bail;
+	dnode = hpfs_alloc_dnode(dir->i_sb, fno, &dno, &qbh0);
+	if (!dnode)
+		goto bail1;
+	memset(&dee, 0, sizeof dee);
+	dee.directory = 1;
+	if (!(mode & 0222)) dee.read_only = 1;
+	/*dee.archive = 0;*/
+	dee.hidden = name[0] == '.';
+	dee.fnode = cpu_to_le32(fno);
+	dee.creation_date = dee.write_date = dee.read_date = cpu_to_le32(local_get_seconds(dir->i_sb));
+	result = new_inode(dir->i_sb);
+	if (!result)
+		goto bail2;
+	hpfs_init_inode(result);
+	result->i_ino = fno;
+	hpfs_i(result)->i_parent_dir = dir->i_ino;
+	hpfs_i(result)->i_dno = dno;
+	result->i_mtime = result->i_atime =
+		inode_set_ctime(result, local_to_gmt(dir->i_sb, le32_to_cpu(dee.creation_date)), 0);
+	hpfs_i(result)->i_ea_size = 0;
+	result->i_mode |= S_IFDIR;
+	result->i_op = &hpfs_dir_iops;
+	result->i_fop = &hpfs_dir_ops;
+	result->i_blocks = 4;
+	result->i_size = 2048;
+	set_nlink(result, 2);
+	if (dee.read_only)
+		result->i_mode &= ~0222;
+
+	r = hpfs_add_dirent(dir, name, len, &dee);
+	if (r == 1)
+		goto bail3;
+	if (r == -1) {
+		err = -EEXIST;
+		goto bail3;
+	}
+	fnode->len = len;
+	memcpy(fnode->name, name, len > 15 ? 15 : len);
+	fnode->up = cpu_to_le32(dir->i_ino);
+	fnode->flags |= FNODE_dir;
+	fnode->btree.n_free_nodes = 7;
+	fnode->btree.n_used_nodes = 1;
+	fnode->btree.first_free = cpu_to_le16(0x14);
+	fnode->u.external[0].disk_secno = cpu_to_le32(dno);
+	fnode->u.external[0].file_secno = cpu_to_le32(-1);
+	dnode->root_dnode = 1;
+	dnode->up = cpu_to_le32(fno);
+	de = hpfs_add_de(dir->i_sb, dnode, "\001\001", 2, 0);
+	de->creation_date = de->write_date = de->read_date = cpu_to_le32(local_get_seconds(dir->i_sb));
+	if (!(mode & 0222)) de->read_only = 1;
+	de->first = de->directory = 1;
+	/*de->hidden = de->system = 0;*/
+	de->fnode = cpu_to_le32(fno);
+	mark_buffer_dirty(bh);
+	brelse(bh);
+	hpfs_mark_4buffers_dirty(&qbh0);
+	hpfs_brelse4(&qbh0);
+	inc_nlink(dir);
+	insert_inode_hash(result);
+
+	if (!uid_eq(result->i_uid, current_fsuid()) ||
+	    !gid_eq(result->i_gid, current_fsgid()) ||
+	    result->i_mode != (mode | S_IFDIR)) {
+		result->i_uid = current_fsuid();
+		result->i_gid = current_fsgid();
+		result->i_mode = mode | S_IFDIR;
+		hpfs_write_inode_nolock(result);
+	}
+	hpfs_update_directory_times(dir);
+	d_instantiate(dentry, result);
+	hpfs_unlock(dir->i_sb);
+	return 0;
+bail3:
+	iput(result);
+bail2:
+	hpfs_brelse4(&qbh0);
+	hpfs_free_dnode(dir->i_sb, dno);
+bail1:
+	brelse(bh);
+	hpfs_free_sectors(dir->i_sb, fno, 1);
+bail:
+	hpfs_unlock(dir->i_sb);
+	return err;
+}
+
+static int hpfs_create(struct mnt_idmap *idmap, struct inode *dir,
+		       struct dentry *dentry, umode_t mode, bool excl)
+{
+	const unsigned char *name = dentry->d_name.name;
+	unsigned len = dentry->d_name.len;
+	struct inode *result = NULL;
+	struct buffer_head *bh;
+	struct fnode *fnode;
+	fnode_secno fno;
+	int r;
+	struct hpfs_dirent dee;
+	int err;
+	if ((err = hpfs_chk_name(name, &len)))
+		return err==-ENOENT ? -EINVAL : err;
+	hpfs_lock(dir->i_sb);
+	err = -ENOSPC;
+	fnode = hpfs_alloc_fnode(dir->i_sb, hpfs_i(dir)->i_dno, &fno, &bh);
+	if (!fnode)
+		goto bail;
+	memset(&dee, 0, sizeof dee);
+	if (!(mode & 0222)) dee.read_only = 1;
+	dee.archive = 1;
+	dee.hidden = name[0] == '.';
+	dee.fnode = cpu_to_le32(fno);
+	dee.creation_date = dee.write_date = dee.read_date = cpu_to_le32(local_get_seconds(dir->i_sb));
+
+	result = new_inode(dir->i_sb);
+	if (!result)
+		goto bail1;
+	
+	hpfs_init_inode(result);
+	result->i_ino = fno;
+	result->i_mode |= S_IFREG;
+	result->i_mode &= ~0111;
+	result->i_op = &hpfs_file_iops;
+	result->i_fop = &hpfs_file_ops;
+	set_nlink(result, 1);
+	hpfs_i(result)->i_parent_dir = dir->i_ino;
+	result->i_mtime = result->i_atime =
+		inode_set_ctime(result, local_to_gmt(dir->i_sb, le32_to_cpu(dee.creation_date)), 0);
+	hpfs_i(result)->i_ea_size = 0;
+	if (dee.read_only)
+		result->i_mode &= ~0222;
+	result->i_blocks = 1;
+	result->i_size = 0;
+	result->i_data.a_ops = &hpfs_aops;
+	hpfs_i(result)->mmu_private = 0;
+
+	r = hpfs_add_dirent(dir, name, len, &dee);
+	if (r == 1)
+		goto bail2;
+	if (r == -1) {
+		err = -EEXIST;
+		goto bail2;
+	}
+	fnode->len = len;
+	memcpy(fnode->name, name, len > 15 ? 15 : len);
+	fnode->up = cpu_to_le32(dir->i_ino);
+	mark_buffer_dirty(bh);
+	brelse(bh);
+
+	insert_inode_hash(result);
+
+	if (!uid_eq(result->i_uid, current_fsuid()) ||
+	    !gid_eq(result->i_gid, current_fsgid()) ||
+	    result->i_mode != (mode | S_IFREG)) {
+		result->i_uid = current_fsuid();
+		result->i_gid = current_fsgid();
+		result->i_mode = mode | S_IFREG;
+		hpfs_write_inode_nolock(result);
+	}
+	hpfs_update_directory_times(dir);
+	d_instantiate(dentry, result);
+	hpfs_unlock(dir->i_sb);
+	return 0;
+
+bail2:
+	iput(result);
+bail1:
+	brelse(bh);
+	hpfs_free_sectors(dir->i_sb, fno, 1);
+bail:
+	hpfs_unlock(dir->i_sb);
+	return err;
+}
+
+static int hpfs_mknod(struct mnt_idmap *idmap, struct inode *dir,
+		      struct dentry *dentry, umode_t mode, dev_t rdev)
+{
+	const unsigned char *name = dentry->d_name.name;
+	unsigned len = dentry->d_name.len;
+	struct buffer_head *bh;
+	struct fnode *fnode;
+	fnode_secno fno;
+	int r;
+	struct hpfs_dirent dee;
+	struct inode *result = NULL;
+	int err;
+	if ((err = hpfs_chk_name(name, &len))) return err==-ENOENT ? -EINVAL : err;
+	if (hpfs_sb(dir->i_sb)->sb_eas < 2) return -EPERM;
+	hpfs_lock(dir->i_sb);
+	err = -ENOSPC;
+	fnode = hpfs_alloc_fnode(dir->i_sb, hpfs_i(dir)->i_dno, &fno, &bh);
+	if (!fnode)
+		goto bail;
+	memset(&dee, 0, sizeof dee);
+	if (!(mode & 0222)) dee.read_only = 1;
+	dee.archive = 1;
+	dee.hidden = name[0] == '.';
+	dee.fnode = cpu_to_le32(fno);
+	dee.creation_date = dee.write_date = dee.read_date = cpu_to_le32(local_get_seconds(dir->i_sb));
+
+	result = new_inode(dir->i_sb);
+	if (!result)
+		goto bail1;
+
+	hpfs_init_inode(result);
+	result->i_ino = fno;
+	hpfs_i(result)->i_parent_dir = dir->i_ino;
+	result->i_mtime = result->i_atime =
+		inode_set_ctime(result, local_to_gmt(dir->i_sb, le32_to_cpu(dee.creation_date)), 0);
+	hpfs_i(result)->i_ea_size = 0;
+	result->i_uid = current_fsuid();
+	result->i_gid = current_fsgid();
+	set_nlink(result, 1);
+	result->i_size = 0;
+	result->i_blocks = 1;
+	init_special_inode(result, mode, rdev);
+
+	r = hpfs_add_dirent(dir, name, len, &dee);
+	if (r == 1)
+		goto bail2;
+	if (r == -1) {
+		err = -EEXIST;
+		goto bail2;
+	}
+	fnode->len = len;
+	memcpy(fnode->name, name, len > 15 ? 15 : len);
+	fnode->up = cpu_to_le32(dir->i_ino);
+	mark_buffer_dirty(bh);
+
+	insert_inode_hash(result);
+
+	hpfs_write_inode_nolock(result);
+	hpfs_update_directory_times(dir);
+	d_instantiate(dentry, result);
+	brelse(bh);
+	hpfs_unlock(dir->i_sb);
+	return 0;
+bail2:
+	iput(result);
+bail1:
+	brelse(bh);
+	hpfs_free_sectors(dir->i_sb, fno, 1);
+bail:
+	hpfs_unlock(dir->i_sb);
+	return err;
+}
+
+static int hpfs_symlink(struct mnt_idmap *idmap, struct inode *dir,
+			struct dentry *dentry, const char *symlink)
+{
+	const unsigned char *name = dentry->d_name.name;
+	unsigned len = dentry->d_name.len;
+	struct buffer_head *bh;
+	struct fnode *fnode;
+	fnode_secno fno;
+	int r;
+	struct hpfs_dirent dee;
+	struct inode *result;
+	int err;
+	if ((err = hpfs_chk_name(name, &len))) return err==-ENOENT ? -EINVAL : err;
+	hpfs_lock(dir->i_sb);
+	if (hpfs_sb(dir->i_sb)->sb_eas < 2) {
+		hpfs_unlock(dir->i_sb);
+		return -EPERM;
+	}
+	err = -ENOSPC;
+	fnode = hpfs_alloc_fnode(dir->i_sb, hpfs_i(dir)->i_dno, &fno, &bh);
+	if (!fnode)
+		goto bail;
+	memset(&dee, 0, sizeof dee);
+	dee.archive = 1;
+	dee.hidden = name[0] == '.';
+	dee.fnode = cpu_to_le32(fno);
+	dee.creation_date = dee.write_date = dee.read_date = cpu_to_le32(local_get_seconds(dir->i_sb));
+
+	result = new_inode(dir->i_sb);
+	if (!result)
+		goto bail1;
+	result->i_ino = fno;
+	hpfs_init_inode(result);
+	hpfs_i(result)->i_parent_dir = dir->i_ino;
+	result->i_mtime = result->i_atime =
+		inode_set_ctime(result, local_to_gmt(dir->i_sb, le32_to_cpu(dee.creation_date)), 0);
+	hpfs_i(result)->i_ea_size = 0;
+	result->i_mode = S_IFLNK | 0777;
+	result->i_uid = current_fsuid();
+	result->i_gid = current_fsgid();
+	result->i_blocks = 1;
+	set_nlink(result, 1);
+	result->i_size = strlen(symlink);
+	inode_nohighmem(result);
+	result->i_op = &page_symlink_inode_operations;
+	result->i_data.a_ops = &hpfs_symlink_aops;
+
+	r = hpfs_add_dirent(dir, name, len, &dee);
+	if (r == 1)
+		goto bail2;
+	if (r == -1) {
+		err = -EEXIST;
+		goto bail2;
+	}
+	fnode->len = len;
+	memcpy(fnode->name, name, len > 15 ? 15 : len);
+	fnode->up = cpu_to_le32(dir->i_ino);
+	hpfs_set_ea(result, fnode, "SYMLINK", symlink, strlen(symlink));
+	mark_buffer_dirty(bh);
+	brelse(bh);
+
+	insert_inode_hash(result);
+
+	hpfs_write_inode_nolock(result);
+	hpfs_update_directory_times(dir);
+	d_instantiate(dentry, result);
+	hpfs_unlock(dir->i_sb);
+	return 0;
+bail2:
+	iput(result);
+bail1:
+	brelse(bh);
+	hpfs_free_sectors(dir->i_sb, fno, 1);
+bail:
+	hpfs_unlock(dir->i_sb);
+	return err;
+}
+
+static int hpfs_unlink(struct inode *dir, struct dentry *dentry)
+{
+	const unsigned char *name = dentry->d_name.name;
+	unsigned len = dentry->d_name.len;
+	struct quad_buffer_head qbh;
+	struct hpfs_dirent *de;
+	struct inode *inode = d_inode(dentry);
+	dnode_secno dno;
+	int r;
+	int err;
+
+	hpfs_lock(dir->i_sb);
+	hpfs_adjust_length(name, &len);
+
+	err = -ENOENT;
+	de = map_dirent(dir, hpfs_i(dir)->i_dno, name, len, &dno, &qbh);
+	if (!de)
+		goto out;
+
+	err = -EPERM;
+	if (de->first)
+		goto out1;
+
+	err = -EISDIR;
+	if (de->directory)
+		goto out1;
+
+	r = hpfs_remove_dirent(dir, dno, de, &qbh, 1);
+	switch (r) {
+	case 1:
+		hpfs_error(dir->i_sb, "there was error when removing dirent");
+		err = -EFSERROR;
+		break;
+	case 2:		/* no space for deleting */
+		err = -ENOSPC;
+		break;
+	default:
+		drop_nlink(inode);
+		err = 0;
+	}
+	goto out;
+
+out1:
+	hpfs_brelse4(&qbh);
+out:
+	if (!err)
+		hpfs_update_directory_times(dir);
+	hpfs_unlock(dir->i_sb);
+	return err;
+}
+
+static int hpfs_rmdir(struct inode *dir, struct dentry *dentry)
+{
+	const unsigned char *name = dentry->d_name.name;
+	unsigned len = dentry->d_name.len;
+	struct quad_buffer_head qbh;
+	struct hpfs_dirent *de;
+	struct inode *inode = d_inode(dentry);
+	dnode_secno dno;
+	int n_items = 0;
+	int err;
+	int r;
+
+	hpfs_adjust_length(name, &len);
+	hpfs_lock(dir->i_sb);
+	err = -ENOENT;
+	de = map_dirent(dir, hpfs_i(dir)->i_dno, name, len, &dno, &qbh);
+	if (!de)
+		goto out;
+
+	err = -EPERM;
+	if (de->first)
+		goto out1;
+
+	err = -ENOTDIR;
+	if (!de->directory)
+		goto out1;
+
+	hpfs_count_dnodes(dir->i_sb, hpfs_i(inode)->i_dno, NULL, NULL, &n_items);
+	err = -ENOTEMPTY;
+	if (n_items)
+		goto out1;
+
+	r = hpfs_remove_dirent(dir, dno, de, &qbh, 1);
+	switch (r) {
+	case 1:
+		hpfs_error(dir->i_sb, "there was error when removing dirent");
+		err = -EFSERROR;
+		break;
+	case 2:
+		err = -ENOSPC;
+		break;
+	default:
+		drop_nlink(dir);
+		clear_nlink(inode);
+		err = 0;
+	}
+	goto out;
+out1:
+	hpfs_brelse4(&qbh);
+out:
+	if (!err)
+		hpfs_update_directory_times(dir);
+	hpfs_unlock(dir->i_sb);
+	return err;
+}
+
+static int hpfs_symlink_read_folio(struct file *file, struct folio *folio)
+{
+	struct page *page = &folio->page;
+	char *link = page_address(page);
+	struct inode *i = page->mapping->host;
+	struct fnode *fnode;
+	struct buffer_head *bh;
+	int err;
+
+	err = -EIO;
+	hpfs_lock(i->i_sb);
+	if (!(fnode = hpfs_map_fnode(i->i_sb, i->i_ino, &bh)))
+		goto fail;
+	err = hpfs_read_ea(i->i_sb, fnode, "SYMLINK", link, PAGE_SIZE);
+	brelse(bh);
+	if (err)
+		goto fail;
+	hpfs_unlock(i->i_sb);
+	SetPageUptodate(page);
+	unlock_page(page);
+	return 0;
+
+fail:
+	hpfs_unlock(i->i_sb);
+	SetPageError(page);
+	unlock_page(page);
+	return err;
+}
+
+const struct address_space_operations hpfs_symlink_aops = {
+	.read_folio	= hpfs_symlink_read_folio
+};
+
+static int hpfs_rename(struct mnt_idmap *idmap, struct inode *old_dir,
+		       struct dentry *old_dentry, struct inode *new_dir,
+		       struct dentry *new_dentry, unsigned int flags)
+{
+	const unsigned char *old_name = old_dentry->d_name.name;
+	unsigned old_len = old_dentry->d_name.len;
+	const unsigned char *new_name = new_dentry->d_name.name;
+	unsigned new_len = new_dentry->d_name.len;
+	struct inode *i = d_inode(old_dentry);
+	struct inode *new_inode = d_inode(new_dentry);
+	struct quad_buffer_head qbh, qbh1;
+	struct hpfs_dirent *dep, *nde;
+	struct hpfs_dirent de;
+	dnode_secno dno;
+	int r;
+	struct buffer_head *bh;
+	struct fnode *fnode;
+	int err;
+
+	if (flags & ~RENAME_NOREPLACE)
+		return -EINVAL;
+
+	if ((err = hpfs_chk_name(new_name, &new_len))) return err;
+	err = 0;
+	hpfs_adjust_length(old_name, &old_len);
+
+	hpfs_lock(i->i_sb);
+	/* order doesn't matter, due to VFS exclusion */
+	
+	/* Erm? Moving over the empty non-busy directory is perfectly legal */
+	if (new_inode && S_ISDIR(new_inode->i_mode)) {
+		err = -EINVAL;
+		goto end1;
+	}
+
+	if (!(dep = map_dirent(old_dir, hpfs_i(old_dir)->i_dno, old_name, old_len, &dno, &qbh))) {
+		hpfs_error(i->i_sb, "lookup succeeded but map dirent failed");
+		err = -ENOENT;
+		goto end1;
+	}
+	copy_de(&de, dep);
+	de.hidden = new_name[0] == '.';
+
+	if (new_inode) {
+		int r;
+		if ((r = hpfs_remove_dirent(old_dir, dno, dep, &qbh, 1)) != 2) {
+			if ((nde = map_dirent(new_dir, hpfs_i(new_dir)->i_dno, new_name, new_len, NULL, &qbh1))) {
+				clear_nlink(new_inode);
+				copy_de(nde, &de);
+				memcpy(nde->name, new_name, new_len);
+				hpfs_mark_4buffers_dirty(&qbh1);
+				hpfs_brelse4(&qbh1);
+				goto end;
+			}
+			hpfs_error(new_dir->i_sb, "hpfs_rename: could not find dirent");
+			err = -EFSERROR;
+			goto end1;
+		}
+		err = -ENOSPC;
+		goto end1;
+	}
+
+	if (new_dir == old_dir) hpfs_brelse4(&qbh);
+
+	if ((r = hpfs_add_dirent(new_dir, new_name, new_len, &de))) {
+		if (r == -1) hpfs_error(new_dir->i_sb, "hpfs_rename: dirent already exists!");
+		err = r == 1 ? -ENOSPC : -EFSERROR;
+		if (new_dir != old_dir) hpfs_brelse4(&qbh);
+		goto end1;
+	}
+	
+	if (new_dir == old_dir)
+		if (!(dep = map_dirent(old_dir, hpfs_i(old_dir)->i_dno, old_name, old_len, &dno, &qbh))) {
+			hpfs_error(i->i_sb, "lookup succeeded but map dirent failed at #2");
+			err = -ENOENT;
+			goto end1;
+		}
+
+	if ((r = hpfs_remove_dirent(old_dir, dno, dep, &qbh, 0))) {
+		hpfs_error(i->i_sb, "hpfs_rename: could not remove dirent");
+		err = r == 2 ? -ENOSPC : -EFSERROR;
+		goto end1;
+	}
+
+end:
+	hpfs_i(i)->i_parent_dir = new_dir->i_ino;
+	if (S_ISDIR(i->i_mode)) {
+		inc_nlink(new_dir);
+		drop_nlink(old_dir);
+	}
+	if ((fnode = hpfs_map_fnode(i->i_sb, i->i_ino, &bh))) {
+		fnode->up = cpu_to_le32(new_dir->i_ino);
+		fnode->len = new_len;
+		memcpy(fnode->name, new_name, new_len>15?15:new_len);
+		if (new_len < 15) memset(&fnode->name[new_len], 0, 15 - new_len);
+		mark_buffer_dirty(bh);
+		brelse(bh);
+	}
+end1:
+	if (!err) {
+		hpfs_update_directory_times(old_dir);
+		hpfs_update_directory_times(new_dir);
+	}
+	hpfs_unlock(i->i_sb);
+	return err;
+}
+
+const struct inode_operations hpfs_dir_iops =
+{
+	.create		= hpfs_create,
+	.lookup		= hpfs_lookup,
+	.unlink		= hpfs_unlink,
+	.symlink	= hpfs_symlink,
+	.mkdir		= hpfs_mkdir,
+	.rmdir		= hpfs_rmdir,
+	.mknod		= hpfs_mknod,
+	.rename		= hpfs_rename,
+	.setattr	= hpfs_setattr,
+};
diff --git a/fs/hpfs/super.c b/fs/hpfs/super.c
new file mode 100644
index 0000000000..758a515641
--- /dev/null
+++ b/fs/hpfs/super.c
@@ -0,0 +1,794 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  linux/fs/hpfs/super.c
+ *
+ *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
+ *
+ *  mounting, unmounting, error handling
+ */
+
+#include "hpfs_fn.h"
+#include <linux/module.h>
+#include <linux/parser.h>
+#include <linux/init.h>
+#include <linux/statfs.h>
+#include <linux/magic.h>
+#include <linux/sched.h>
+#include <linux/bitmap.h>
+#include <linux/slab.h>
+#include <linux/seq_file.h>
+
+/* Mark the filesystem dirty, so that chkdsk checks it when os/2 booted */
+
+static void mark_dirty(struct super_block *s, int remount)
+{
+	if (hpfs_sb(s)->sb_chkdsk && (remount || !sb_rdonly(s))) {
+		struct buffer_head *bh;
+		struct hpfs_spare_block *sb;
+		if ((sb = hpfs_map_sector(s, 17, &bh, 0))) {
+			sb->dirty = 1;
+			sb->old_wrote = 0;
+			mark_buffer_dirty(bh);
+			sync_dirty_buffer(bh);
+			brelse(bh);
+		}
+	}
+}
+
+/* Mark the filesystem clean (mark it dirty for chkdsk if chkdsk==2 or if there
+   were errors) */
+
+static void unmark_dirty(struct super_block *s)
+{
+	struct buffer_head *bh;
+	struct hpfs_spare_block *sb;
+	if (sb_rdonly(s)) return;
+	sync_blockdev(s->s_bdev);
+	if ((sb = hpfs_map_sector(s, 17, &bh, 0))) {
+		sb->dirty = hpfs_sb(s)->sb_chkdsk > 1 - hpfs_sb(s)->sb_was_error;
+		sb->old_wrote = hpfs_sb(s)->sb_chkdsk >= 2 && !hpfs_sb(s)->sb_was_error;
+		mark_buffer_dirty(bh);
+		sync_dirty_buffer(bh);
+		brelse(bh);
+	}
+}
+
+/* Filesystem error... */
+void hpfs_error(struct super_block *s, const char *fmt, ...)
+{
+	struct va_format vaf;
+	va_list args;
+
+	va_start(args, fmt);
+
+	vaf.fmt = fmt;
+	vaf.va = &args;
+
+	pr_err("filesystem error: %pV", &vaf);
+
+	va_end(args);
+
+	if (!hpfs_sb(s)->sb_was_error) {
+		if (hpfs_sb(s)->sb_err == 2) {
+			pr_cont("; crashing the system because you wanted it\n");
+			mark_dirty(s, 0);
+			panic("HPFS panic");
+		} else if (hpfs_sb(s)->sb_err == 1) {
+			if (sb_rdonly(s))
+				pr_cont("; already mounted read-only\n");
+			else {
+				pr_cont("; remounting read-only\n");
+				mark_dirty(s, 0);
+				s->s_flags |= SB_RDONLY;
+			}
+		} else if (sb_rdonly(s))
+				pr_cont("; going on - but anything won't be destroyed because it's read-only\n");
+		else
+			pr_cont("; corrupted filesystem mounted read/write - your computer will explode within 20 seconds ... but you wanted it so!\n");
+	} else
+		pr_cont("\n");
+	hpfs_sb(s)->sb_was_error = 1;
+}
+
+/* 
+ * A little trick to detect cycles in many hpfs structures and don't let the
+ * kernel crash on corrupted filesystem. When first called, set c2 to 0.
+ *
+ * BTW. chkdsk doesn't detect cycles correctly. When I had 2 lost directories
+ * nested each in other, chkdsk locked up happilly.
+ */
+
+int hpfs_stop_cycles(struct super_block *s, int key, int *c1, int *c2,
+		char *msg)
+{
+	if (*c2 && *c1 == key) {
+		hpfs_error(s, "cycle detected on key %08x in %s", key, msg);
+		return 1;
+	}
+	(*c2)++;
+	if (!((*c2 - 1) & *c2)) *c1 = key;
+	return 0;
+}
+
+static void free_sbi(struct hpfs_sb_info *sbi)
+{
+	kfree(sbi->sb_cp_table);
+	kfree(sbi->sb_bmp_dir);
+	kfree(sbi);
+}
+
+static void lazy_free_sbi(struct rcu_head *rcu)
+{
+	free_sbi(container_of(rcu, struct hpfs_sb_info, rcu));
+}
+
+static void hpfs_put_super(struct super_block *s)
+{
+	hpfs_lock(s);
+	unmark_dirty(s);
+	hpfs_unlock(s);
+	call_rcu(&hpfs_sb(s)->rcu, lazy_free_sbi);
+}
+
+static unsigned hpfs_count_one_bitmap(struct super_block *s, secno secno)
+{
+	struct quad_buffer_head qbh;
+	unsigned long *bits;
+	unsigned count;
+
+	bits = hpfs_map_4sectors(s, secno, &qbh, 0);
+	if (!bits)
+		return (unsigned)-1;
+	count = bitmap_weight(bits, 2048 * BITS_PER_BYTE);
+	hpfs_brelse4(&qbh);
+	return count;
+}
+
+static unsigned count_bitmaps(struct super_block *s)
+{
+	unsigned n, count, n_bands;
+	n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14;
+	count = 0;
+	for (n = 0; n < COUNT_RD_AHEAD; n++) {
+		hpfs_prefetch_bitmap(s, n);
+	}
+	for (n = 0; n < n_bands; n++) {
+		unsigned c;
+		hpfs_prefetch_bitmap(s, n + COUNT_RD_AHEAD);
+		c = hpfs_count_one_bitmap(s, le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[n]));
+		if (c != (unsigned)-1)
+			count += c;
+	}
+	return count;
+}
+
+unsigned hpfs_get_free_dnodes(struct super_block *s)
+{
+	struct hpfs_sb_info *sbi = hpfs_sb(s);
+	if (sbi->sb_n_free_dnodes == (unsigned)-1) {
+		unsigned c = hpfs_count_one_bitmap(s, sbi->sb_dmap);
+		if (c == (unsigned)-1)
+			return 0;
+		sbi->sb_n_free_dnodes = c;
+	}
+	return sbi->sb_n_free_dnodes;
+}
+
+static int hpfs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	struct super_block *s = dentry->d_sb;
+	struct hpfs_sb_info *sbi = hpfs_sb(s);
+	u64 id = huge_encode_dev(s->s_bdev->bd_dev);
+
+	hpfs_lock(s);
+
+	if (sbi->sb_n_free == (unsigned)-1)
+		sbi->sb_n_free = count_bitmaps(s);
+
+	buf->f_type = s->s_magic;
+	buf->f_bsize = 512;
+	buf->f_blocks = sbi->sb_fs_size;
+	buf->f_bfree = sbi->sb_n_free;
+	buf->f_bavail = sbi->sb_n_free;
+	buf->f_files = sbi->sb_dirband_size / 4;
+	buf->f_ffree = hpfs_get_free_dnodes(s);
+	buf->f_fsid = u64_to_fsid(id);
+	buf->f_namelen = 254;
+
+	hpfs_unlock(s);
+
+	return 0;
+}
+
+
+long hpfs_ioctl(struct file *file, unsigned cmd, unsigned long arg)
+{
+	switch (cmd) {
+		case FITRIM: {
+			struct fstrim_range range;
+			secno n_trimmed;
+			int r;
+			if (!capable(CAP_SYS_ADMIN))
+				return -EPERM;
+			if (copy_from_user(&range, (struct fstrim_range __user *)arg, sizeof(range)))
+				return -EFAULT;
+			r = hpfs_trim_fs(file_inode(file)->i_sb, range.start >> 9, (range.start + range.len) >> 9, (range.minlen + 511) >> 9, &n_trimmed);
+			if (r)
+				return r;
+			range.len = (u64)n_trimmed << 9;
+			if (copy_to_user((struct fstrim_range __user *)arg, &range, sizeof(range)))
+				return -EFAULT;
+			return 0;
+		}
+		default: {
+			return -ENOIOCTLCMD;
+		}
+	}
+}
+
+
+static struct kmem_cache * hpfs_inode_cachep;
+
+static struct inode *hpfs_alloc_inode(struct super_block *sb)
+{
+	struct hpfs_inode_info *ei;
+	ei = alloc_inode_sb(sb, hpfs_inode_cachep, GFP_NOFS);
+	if (!ei)
+		return NULL;
+	return &ei->vfs_inode;
+}
+
+static void hpfs_free_inode(struct inode *inode)
+{
+	kmem_cache_free(hpfs_inode_cachep, hpfs_i(inode));
+}
+
+static void init_once(void *foo)
+{
+	struct hpfs_inode_info *ei = (struct hpfs_inode_info *) foo;
+
+	inode_init_once(&ei->vfs_inode);
+}
+
+static int init_inodecache(void)
+{
+	hpfs_inode_cachep = kmem_cache_create("hpfs_inode_cache",
+					     sizeof(struct hpfs_inode_info),
+					     0, (SLAB_RECLAIM_ACCOUNT|
+						SLAB_MEM_SPREAD|SLAB_ACCOUNT),
+					     init_once);
+	if (hpfs_inode_cachep == NULL)
+		return -ENOMEM;
+	return 0;
+}
+
+static void destroy_inodecache(void)
+{
+	/*
+	 * Make sure all delayed rcu free inodes are flushed before we
+	 * destroy cache.
+	 */
+	rcu_barrier();
+	kmem_cache_destroy(hpfs_inode_cachep);
+}
+
+/*
+ * A tiny parser for option strings, stolen from dosfs.
+ * Stolen again from read-only hpfs.
+ * And updated for table-driven option parsing.
+ */
+
+enum {
+	Opt_help, Opt_uid, Opt_gid, Opt_umask, Opt_case_lower, Opt_case_asis,
+	Opt_check_none, Opt_check_normal, Opt_check_strict,
+	Opt_err_cont, Opt_err_ro, Opt_err_panic,
+	Opt_eas_no, Opt_eas_ro, Opt_eas_rw,
+	Opt_chkdsk_no, Opt_chkdsk_errors, Opt_chkdsk_always,
+	Opt_timeshift, Opt_err,
+};
+
+static const match_table_t tokens = {
+	{Opt_help, "help"},
+	{Opt_uid, "uid=%u"},
+	{Opt_gid, "gid=%u"},
+	{Opt_umask, "umask=%o"},
+	{Opt_case_lower, "case=lower"},
+	{Opt_case_asis, "case=asis"},
+	{Opt_check_none, "check=none"},
+	{Opt_check_normal, "check=normal"},
+	{Opt_check_strict, "check=strict"},
+	{Opt_err_cont, "errors=continue"},
+	{Opt_err_ro, "errors=remount-ro"},
+	{Opt_err_panic, "errors=panic"},
+	{Opt_eas_no, "eas=no"},
+	{Opt_eas_ro, "eas=ro"},
+	{Opt_eas_rw, "eas=rw"},
+	{Opt_chkdsk_no, "chkdsk=no"},
+	{Opt_chkdsk_errors, "chkdsk=errors"},
+	{Opt_chkdsk_always, "chkdsk=always"},
+	{Opt_timeshift, "timeshift=%d"},
+	{Opt_err, NULL},
+};
+
+static int parse_opts(char *opts, kuid_t *uid, kgid_t *gid, umode_t *umask,
+		      int *lowercase, int *eas, int *chk, int *errs,
+		      int *chkdsk, int *timeshift)
+{
+	char *p;
+	int option;
+
+	if (!opts)
+		return 1;
+
+	/*pr_info("Parsing opts: '%s'\n",opts);*/
+
+	while ((p = strsep(&opts, ",")) != NULL) {
+		substring_t args[MAX_OPT_ARGS];
+		int token;
+		if (!*p)
+			continue;
+
+		token = match_token(p, tokens, args);
+		switch (token) {
+		case Opt_help:
+			return 2;
+		case Opt_uid:
+			if (match_int(args, &option))
+				return 0;
+			*uid = make_kuid(current_user_ns(), option);
+			if (!uid_valid(*uid))
+				return 0;
+			break;
+		case Opt_gid:
+			if (match_int(args, &option))
+				return 0;
+			*gid = make_kgid(current_user_ns(), option);
+			if (!gid_valid(*gid))
+				return 0;
+			break;
+		case Opt_umask:
+			if (match_octal(args, &option))
+				return 0;
+			*umask = option;
+			break;
+		case Opt_case_lower:
+			*lowercase = 1;
+			break;
+		case Opt_case_asis:
+			*lowercase = 0;
+			break;
+		case Opt_check_none:
+			*chk = 0;
+			break;
+		case Opt_check_normal:
+			*chk = 1;
+			break;
+		case Opt_check_strict:
+			*chk = 2;
+			break;
+		case Opt_err_cont:
+			*errs = 0;
+			break;
+		case Opt_err_ro:
+			*errs = 1;
+			break;
+		case Opt_err_panic:
+			*errs = 2;
+			break;
+		case Opt_eas_no:
+			*eas = 0;
+			break;
+		case Opt_eas_ro:
+			*eas = 1;
+			break;
+		case Opt_eas_rw:
+			*eas = 2;
+			break;
+		case Opt_chkdsk_no:
+			*chkdsk = 0;
+			break;
+		case Opt_chkdsk_errors:
+			*chkdsk = 1;
+			break;
+		case Opt_chkdsk_always:
+			*chkdsk = 2;
+			break;
+		case Opt_timeshift:
+		{
+			int m = 1;
+			char *rhs = args[0].from;
+			if (!rhs || !*rhs)
+				return 0;
+			if (*rhs == '-') m = -1;
+			if (*rhs == '+' || *rhs == '-') rhs++;
+			*timeshift = simple_strtoul(rhs, &rhs, 0) * m;
+			if (*rhs)
+				return 0;
+			break;
+		}
+		default:
+			return 0;
+		}
+	}
+	return 1;
+}
+
+static inline void hpfs_help(void)
+{
+	pr_info("\n\
+HPFS filesystem options:\n\
+      help              do not mount and display this text\n\
+      uid=xxx           set uid of files that don't have uid specified in eas\n\
+      gid=xxx           set gid of files that don't have gid specified in eas\n\
+      umask=xxx         set mode of files that don't have mode specified in eas\n\
+      case=lower        lowercase all files\n\
+      case=asis         do not lowercase files (default)\n\
+      check=none        no fs checks - kernel may crash on corrupted filesystem\n\
+      check=normal      do some checks - it should not crash (default)\n\
+      check=strict      do extra time-consuming checks, used for debugging\n\
+      errors=continue   continue on errors\n\
+      errors=remount-ro remount read-only if errors found (default)\n\
+      errors=panic      panic on errors\n\
+      chkdsk=no         do not mark fs for chkdsking even if there were errors\n\
+      chkdsk=errors     mark fs dirty if errors found (default)\n\
+      chkdsk=always     always mark fs dirty - used for debugging\n\
+      eas=no            ignore extended attributes\n\
+      eas=ro            read but do not write extended attributes\n\
+      eas=rw            r/w eas => enables chmod, chown, mknod, ln -s (default)\n\
+      timeshift=nnn	add nnn seconds to file times\n\
+\n");
+}
+
+static int hpfs_remount_fs(struct super_block *s, int *flags, char *data)
+{
+	kuid_t uid;
+	kgid_t gid;
+	umode_t umask;
+	int lowercase, eas, chk, errs, chkdsk, timeshift;
+	int o;
+	struct hpfs_sb_info *sbi = hpfs_sb(s);
+
+	sync_filesystem(s);
+
+	*flags |= SB_NOATIME;
+
+	hpfs_lock(s);
+	uid = sbi->sb_uid; gid = sbi->sb_gid;
+	umask = 0777 & ~sbi->sb_mode;
+	lowercase = sbi->sb_lowercase;
+	eas = sbi->sb_eas; chk = sbi->sb_chk; chkdsk = sbi->sb_chkdsk;
+	errs = sbi->sb_err; timeshift = sbi->sb_timeshift;
+
+	if (!(o = parse_opts(data, &uid, &gid, &umask, &lowercase,
+	    &eas, &chk, &errs, &chkdsk, &timeshift))) {
+		pr_err("bad mount options.\n");
+		goto out_err;
+	}
+	if (o == 2) {
+		hpfs_help();
+		goto out_err;
+	}
+	if (timeshift != sbi->sb_timeshift) {
+		pr_err("timeshift can't be changed using remount.\n");
+		goto out_err;
+	}
+
+	unmark_dirty(s);
+
+	sbi->sb_uid = uid; sbi->sb_gid = gid;
+	sbi->sb_mode = 0777 & ~umask;
+	sbi->sb_lowercase = lowercase;
+	sbi->sb_eas = eas; sbi->sb_chk = chk; sbi->sb_chkdsk = chkdsk;
+	sbi->sb_err = errs; sbi->sb_timeshift = timeshift;
+
+	if (!(*flags & SB_RDONLY)) mark_dirty(s, 1);
+
+	hpfs_unlock(s);
+	return 0;
+
+out_err:
+	hpfs_unlock(s);
+	return -EINVAL;
+}
+
+static int hpfs_show_options(struct seq_file *seq, struct dentry *root)
+{
+	struct hpfs_sb_info *sbi = hpfs_sb(root->d_sb);
+
+	seq_printf(seq, ",uid=%u", from_kuid_munged(&init_user_ns, sbi->sb_uid));
+	seq_printf(seq, ",gid=%u", from_kgid_munged(&init_user_ns, sbi->sb_gid));
+	seq_printf(seq, ",umask=%03o", (~sbi->sb_mode & 0777));
+	if (sbi->sb_lowercase)
+		seq_printf(seq, ",case=lower");
+	if (!sbi->sb_chk)
+		seq_printf(seq, ",check=none");
+	if (sbi->sb_chk == 2)
+		seq_printf(seq, ",check=strict");
+	if (!sbi->sb_err)
+		seq_printf(seq, ",errors=continue");
+	if (sbi->sb_err == 2)
+		seq_printf(seq, ",errors=panic");
+	if (!sbi->sb_chkdsk)
+		seq_printf(seq, ",chkdsk=no");
+	if (sbi->sb_chkdsk == 2)
+		seq_printf(seq, ",chkdsk=always");
+	if (!sbi->sb_eas)
+		seq_printf(seq, ",eas=no");
+	if (sbi->sb_eas == 1)
+		seq_printf(seq, ",eas=ro");
+	if (sbi->sb_timeshift)
+		seq_printf(seq, ",timeshift=%d", sbi->sb_timeshift);
+	return 0;
+}
+
+/* Super operations */
+
+static const struct super_operations hpfs_sops =
+{
+	.alloc_inode	= hpfs_alloc_inode,
+	.free_inode	= hpfs_free_inode,
+	.evict_inode	= hpfs_evict_inode,
+	.put_super	= hpfs_put_super,
+	.statfs		= hpfs_statfs,
+	.remount_fs	= hpfs_remount_fs,
+	.show_options	= hpfs_show_options,
+};
+
+static int hpfs_fill_super(struct super_block *s, void *options, int silent)
+{
+	struct buffer_head *bh0, *bh1, *bh2;
+	struct hpfs_boot_block *bootblock;
+	struct hpfs_super_block *superblock;
+	struct hpfs_spare_block *spareblock;
+	struct hpfs_sb_info *sbi;
+	struct inode *root;
+
+	kuid_t uid;
+	kgid_t gid;
+	umode_t umask;
+	int lowercase, eas, chk, errs, chkdsk, timeshift;
+
+	dnode_secno root_dno;
+	struct hpfs_dirent *de = NULL;
+	struct quad_buffer_head qbh;
+
+	int o;
+
+	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
+	if (!sbi) {
+		return -ENOMEM;
+	}
+	s->s_fs_info = sbi;
+
+	mutex_init(&sbi->hpfs_mutex);
+	hpfs_lock(s);
+
+	uid = current_uid();
+	gid = current_gid();
+	umask = current_umask();
+	lowercase = 0;
+	eas = 2;
+	chk = 1;
+	errs = 1;
+	chkdsk = 1;
+	timeshift = 0;
+
+	if (!(o = parse_opts(options, &uid, &gid, &umask, &lowercase,
+	    &eas, &chk, &errs, &chkdsk, &timeshift))) {
+		pr_err("bad mount options.\n");
+		goto bail0;
+	}
+	if (o==2) {
+		hpfs_help();
+		goto bail0;
+	}
+
+	/*sbi->sb_mounting = 1;*/
+	sb_set_blocksize(s, 512);
+	sbi->sb_fs_size = -1;
+	if (!(bootblock = hpfs_map_sector(s, 0, &bh0, 0))) goto bail1;
+	if (!(superblock = hpfs_map_sector(s, 16, &bh1, 1))) goto bail2;
+	if (!(spareblock = hpfs_map_sector(s, 17, &bh2, 0))) goto bail3;
+
+	/* Check magics */
+	if (/*le16_to_cpu(bootblock->magic) != BB_MAGIC
+	    ||*/ le32_to_cpu(superblock->magic) != SB_MAGIC
+	    || le32_to_cpu(spareblock->magic) != SP_MAGIC) {
+		if (!silent)
+			pr_err("Bad magic ... probably not HPFS\n");
+		goto bail4;
+	}
+
+	/* Check version */
+	if (!sb_rdonly(s) && superblock->funcversion != 2 && superblock->funcversion != 3) {
+		pr_err("Bad version %d,%d. Mount readonly to go around\n",
+			(int)superblock->version, (int)superblock->funcversion);
+		pr_err("please try recent version of HPFS driver at http://artax.karlin.mff.cuni.cz/~mikulas/vyplody/hpfs/index-e.cgi and if it still can't understand this format, contact author - mikulas@artax.karlin.mff.cuni.cz\n");
+		goto bail4;
+	}
+
+	s->s_flags |= SB_NOATIME;
+
+	/* Fill superblock stuff */
+	s->s_magic = HPFS_SUPER_MAGIC;
+	s->s_op = &hpfs_sops;
+	s->s_d_op = &hpfs_dentry_operations;
+	s->s_time_min =  local_to_gmt(s, 0);
+	s->s_time_max =  local_to_gmt(s, U32_MAX);
+
+	sbi->sb_root = le32_to_cpu(superblock->root);
+	sbi->sb_fs_size = le32_to_cpu(superblock->n_sectors);
+	sbi->sb_bitmaps = le32_to_cpu(superblock->bitmaps);
+	sbi->sb_dirband_start = le32_to_cpu(superblock->dir_band_start);
+	sbi->sb_dirband_size = le32_to_cpu(superblock->n_dir_band);
+	sbi->sb_dmap = le32_to_cpu(superblock->dir_band_bitmap);
+	sbi->sb_uid = uid;
+	sbi->sb_gid = gid;
+	sbi->sb_mode = 0777 & ~umask;
+	sbi->sb_n_free = -1;
+	sbi->sb_n_free_dnodes = -1;
+	sbi->sb_lowercase = lowercase;
+	sbi->sb_eas = eas;
+	sbi->sb_chk = chk;
+	sbi->sb_chkdsk = chkdsk;
+	sbi->sb_err = errs;
+	sbi->sb_timeshift = timeshift;
+	sbi->sb_was_error = 0;
+	sbi->sb_cp_table = NULL;
+	sbi->sb_c_bitmap = -1;
+	sbi->sb_max_fwd_alloc = 0xffffff;
+
+	if (sbi->sb_fs_size >= 0x80000000) {
+		hpfs_error(s, "invalid size in superblock: %08x",
+			(unsigned)sbi->sb_fs_size);
+		goto bail4;
+	}
+
+	if (spareblock->n_spares_used)
+		hpfs_load_hotfix_map(s, spareblock);
+
+	/* Load bitmap directory */
+	if (!(sbi->sb_bmp_dir = hpfs_load_bitmap_directory(s, le32_to_cpu(superblock->bitmaps))))
+		goto bail4;
+	
+	/* Check for general fs errors*/
+	if (spareblock->dirty && !spareblock->old_wrote) {
+		if (errs == 2) {
+			pr_err("Improperly stopped, not mounted\n");
+			goto bail4;
+		}
+		hpfs_error(s, "improperly stopped");
+	}
+
+	if (!sb_rdonly(s)) {
+		spareblock->dirty = 1;
+		spareblock->old_wrote = 0;
+		mark_buffer_dirty(bh2);
+	}
+
+	if (le32_to_cpu(spareblock->n_dnode_spares) != le32_to_cpu(spareblock->n_dnode_spares_free)) {
+		if (errs >= 2) {
+			pr_err("Spare dnodes used, try chkdsk\n");
+			mark_dirty(s, 0);
+			goto bail4;
+		}
+		hpfs_error(s, "warning: spare dnodes used, try chkdsk");
+		if (errs == 0)
+			pr_err("Proceeding, but your filesystem could be corrupted if you delete files or directories\n");
+	}
+	if (chk) {
+		unsigned a;
+		if (le32_to_cpu(superblock->dir_band_end) - le32_to_cpu(superblock->dir_band_start) + 1 != le32_to_cpu(superblock->n_dir_band) ||
+		    le32_to_cpu(superblock->dir_band_end) < le32_to_cpu(superblock->dir_band_start) || le32_to_cpu(superblock->n_dir_band) > 0x4000) {
+			hpfs_error(s, "dir band size mismatch: dir_band_start==%08x, dir_band_end==%08x, n_dir_band==%08x",
+				le32_to_cpu(superblock->dir_band_start), le32_to_cpu(superblock->dir_band_end), le32_to_cpu(superblock->n_dir_band));
+			goto bail4;
+		}
+		a = sbi->sb_dirband_size;
+		sbi->sb_dirband_size = 0;
+		if (hpfs_chk_sectors(s, le32_to_cpu(superblock->dir_band_start), le32_to_cpu(superblock->n_dir_band), "dir_band") ||
+		    hpfs_chk_sectors(s, le32_to_cpu(superblock->dir_band_bitmap), 4, "dir_band_bitmap") ||
+		    hpfs_chk_sectors(s, le32_to_cpu(superblock->bitmaps), 4, "bitmaps")) {
+			mark_dirty(s, 0);
+			goto bail4;
+		}
+		sbi->sb_dirband_size = a;
+	} else
+		pr_err("You really don't want any checks? You are crazy...\n");
+
+	/* Load code page table */
+	if (le32_to_cpu(spareblock->n_code_pages))
+		if (!(sbi->sb_cp_table = hpfs_load_code_page(s, le32_to_cpu(spareblock->code_page_dir))))
+			pr_err("code page support is disabled\n");
+
+	brelse(bh2);
+	brelse(bh1);
+	brelse(bh0);
+
+	root = iget_locked(s, sbi->sb_root);
+	if (!root)
+		goto bail0;
+	hpfs_init_inode(root);
+	hpfs_read_inode(root);
+	unlock_new_inode(root);
+	s->s_root = d_make_root(root);
+	if (!s->s_root)
+		goto bail0;
+
+	/*
+	 * find the root directory's . pointer & finish filling in the inode
+	 */
+
+	root_dno = hpfs_fnode_dno(s, sbi->sb_root);
+	if (root_dno)
+		de = map_dirent(root, root_dno, "\001\001", 2, NULL, &qbh);
+	if (!de)
+		hpfs_error(s, "unable to find root dir");
+	else {
+		root->i_atime.tv_sec = local_to_gmt(s, le32_to_cpu(de->read_date));
+		root->i_atime.tv_nsec = 0;
+		root->i_mtime.tv_sec = local_to_gmt(s, le32_to_cpu(de->write_date));
+		root->i_mtime.tv_nsec = 0;
+		inode_set_ctime(root,
+				local_to_gmt(s, le32_to_cpu(de->creation_date)),
+				0);
+		hpfs_i(root)->i_ea_size = le32_to_cpu(de->ea_size);
+		hpfs_i(root)->i_parent_dir = root->i_ino;
+		if (root->i_size == -1)
+			root->i_size = 2048;
+		if (root->i_blocks == -1)
+			root->i_blocks = 5;
+		hpfs_brelse4(&qbh);
+	}
+	hpfs_unlock(s);
+	return 0;
+
+bail4:	brelse(bh2);
+bail3:	brelse(bh1);
+bail2:	brelse(bh0);
+bail1:
+bail0:
+	hpfs_unlock(s);
+	free_sbi(sbi);
+	return -EINVAL;
+}
+
+static struct dentry *hpfs_mount(struct file_system_type *fs_type,
+	int flags, const char *dev_name, void *data)
+{
+	return mount_bdev(fs_type, flags, dev_name, data, hpfs_fill_super);
+}
+
+static struct file_system_type hpfs_fs_type = {
+	.owner		= THIS_MODULE,
+	.name		= "hpfs",
+	.mount		= hpfs_mount,
+	.kill_sb	= kill_block_super,
+	.fs_flags	= FS_REQUIRES_DEV,
+};
+MODULE_ALIAS_FS("hpfs");
+
+static int __init init_hpfs_fs(void)
+{
+	int err = init_inodecache();
+	if (err)
+		goto out1;
+	err = register_filesystem(&hpfs_fs_type);
+	if (err)
+		goto out;
+	return 0;
+out:
+	destroy_inodecache();
+out1:
+	return err;
+}
+
+static void __exit exit_hpfs_fs(void)
+{
+	unregister_filesystem(&hpfs_fs_type);
+	destroy_inodecache();
+}
+
+module_init(init_hpfs_fs)
+module_exit(exit_hpfs_fs)
+MODULE_LICENSE("GPL");