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-rw-r--r--fs/affs/amigaffs.c543
1 files changed, 543 insertions, 0 deletions
diff --git a/fs/affs/amigaffs.c b/fs/affs/amigaffs.c
new file mode 100644
index 0000000000..7ba93efc11
--- /dev/null
+++ b/fs/affs/amigaffs.c
@@ -0,0 +1,543 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/fs/affs/amigaffs.c
+ *
+ * (c) 1996 Hans-Joachim Widmaier - Rewritten
+ *
+ * (C) 1993 Ray Burr - Amiga FFS filesystem.
+ *
+ * Please send bug reports to: hjw@zvw.de
+ */
+
+#include <linux/math64.h>
+#include <linux/iversion.h>
+#include "affs.h"
+
+/*
+ * Functions for accessing Amiga-FFS structures.
+ */
+
+
+/* Insert a header block bh into the directory dir
+ * caller must hold AFFS_DIR->i_hash_lock!
+ */
+
+int
+affs_insert_hash(struct inode *dir, struct buffer_head *bh)
+{
+ struct super_block *sb = dir->i_sb;
+ struct buffer_head *dir_bh;
+ u32 ino, hash_ino;
+ int offset;
+
+ ino = bh->b_blocknr;
+ offset = affs_hash_name(sb, AFFS_TAIL(sb, bh)->name + 1, AFFS_TAIL(sb, bh)->name[0]);
+
+ pr_debug("%s(dir=%lu, ino=%d)\n", __func__, dir->i_ino, ino);
+
+ dir_bh = affs_bread(sb, dir->i_ino);
+ if (!dir_bh)
+ return -EIO;
+
+ hash_ino = be32_to_cpu(AFFS_HEAD(dir_bh)->table[offset]);
+ while (hash_ino) {
+ affs_brelse(dir_bh);
+ dir_bh = affs_bread(sb, hash_ino);
+ if (!dir_bh)
+ return -EIO;
+ hash_ino = be32_to_cpu(AFFS_TAIL(sb, dir_bh)->hash_chain);
+ }
+ AFFS_TAIL(sb, bh)->parent = cpu_to_be32(dir->i_ino);
+ AFFS_TAIL(sb, bh)->hash_chain = 0;
+ affs_fix_checksum(sb, bh);
+
+ if (dir->i_ino == dir_bh->b_blocknr)
+ AFFS_HEAD(dir_bh)->table[offset] = cpu_to_be32(ino);
+ else
+ AFFS_TAIL(sb, dir_bh)->hash_chain = cpu_to_be32(ino);
+
+ affs_adjust_checksum(dir_bh, ino);
+ mark_buffer_dirty_inode(dir_bh, dir);
+ affs_brelse(dir_bh);
+
+ dir->i_mtime = inode_set_ctime_current(dir);
+ inode_inc_iversion(dir);
+ mark_inode_dirty(dir);
+
+ return 0;
+}
+
+/* Remove a header block from its directory.
+ * caller must hold AFFS_DIR->i_hash_lock!
+ */
+
+int
+affs_remove_hash(struct inode *dir, struct buffer_head *rem_bh)
+{
+ struct super_block *sb;
+ struct buffer_head *bh;
+ u32 rem_ino, hash_ino;
+ __be32 ino;
+ int offset, retval;
+
+ sb = dir->i_sb;
+ rem_ino = rem_bh->b_blocknr;
+ offset = affs_hash_name(sb, AFFS_TAIL(sb, rem_bh)->name+1, AFFS_TAIL(sb, rem_bh)->name[0]);
+ pr_debug("%s(dir=%lu, ino=%d, hashval=%d)\n", __func__, dir->i_ino,
+ rem_ino, offset);
+
+ bh = affs_bread(sb, dir->i_ino);
+ if (!bh)
+ return -EIO;
+
+ retval = -ENOENT;
+ hash_ino = be32_to_cpu(AFFS_HEAD(bh)->table[offset]);
+ while (hash_ino) {
+ if (hash_ino == rem_ino) {
+ ino = AFFS_TAIL(sb, rem_bh)->hash_chain;
+ if (dir->i_ino == bh->b_blocknr)
+ AFFS_HEAD(bh)->table[offset] = ino;
+ else
+ AFFS_TAIL(sb, bh)->hash_chain = ino;
+ affs_adjust_checksum(bh, be32_to_cpu(ino) - hash_ino);
+ mark_buffer_dirty_inode(bh, dir);
+ AFFS_TAIL(sb, rem_bh)->parent = 0;
+ retval = 0;
+ break;
+ }
+ affs_brelse(bh);
+ bh = affs_bread(sb, hash_ino);
+ if (!bh)
+ return -EIO;
+ hash_ino = be32_to_cpu(AFFS_TAIL(sb, bh)->hash_chain);
+ }
+
+ affs_brelse(bh);
+
+ dir->i_mtime = inode_set_ctime_current(dir);
+ inode_inc_iversion(dir);
+ mark_inode_dirty(dir);
+
+ return retval;
+}
+
+static void
+affs_fix_dcache(struct inode *inode, u32 entry_ino)
+{
+ struct dentry *dentry;
+ spin_lock(&inode->i_lock);
+ hlist_for_each_entry(dentry, &inode->i_dentry, d_u.d_alias) {
+ if (entry_ino == (u32)(long)dentry->d_fsdata) {
+ dentry->d_fsdata = (void *)inode->i_ino;
+ break;
+ }
+ }
+ spin_unlock(&inode->i_lock);
+}
+
+
+/* Remove header from link chain */
+
+static int
+affs_remove_link(struct dentry *dentry)
+{
+ struct inode *dir, *inode = d_inode(dentry);
+ struct super_block *sb = inode->i_sb;
+ struct buffer_head *bh, *link_bh = NULL;
+ u32 link_ino, ino;
+ int retval;
+
+ pr_debug("%s(key=%ld)\n", __func__, inode->i_ino);
+ retval = -EIO;
+ bh = affs_bread(sb, inode->i_ino);
+ if (!bh)
+ goto done;
+
+ link_ino = (u32)(long)dentry->d_fsdata;
+ if (inode->i_ino == link_ino) {
+ /* we can't remove the head of the link, as its blocknr is still used as ino,
+ * so we remove the block of the first link instead.
+ */
+ link_ino = be32_to_cpu(AFFS_TAIL(sb, bh)->link_chain);
+ link_bh = affs_bread(sb, link_ino);
+ if (!link_bh)
+ goto done;
+
+ dir = affs_iget(sb, be32_to_cpu(AFFS_TAIL(sb, link_bh)->parent));
+ if (IS_ERR(dir)) {
+ retval = PTR_ERR(dir);
+ goto done;
+ }
+
+ affs_lock_dir(dir);
+ /*
+ * if there's a dentry for that block, make it
+ * refer to inode itself.
+ */
+ affs_fix_dcache(inode, link_ino);
+ retval = affs_remove_hash(dir, link_bh);
+ if (retval) {
+ affs_unlock_dir(dir);
+ goto done;
+ }
+ mark_buffer_dirty_inode(link_bh, inode);
+
+ memcpy(AFFS_TAIL(sb, bh)->name, AFFS_TAIL(sb, link_bh)->name, 32);
+ retval = affs_insert_hash(dir, bh);
+ if (retval) {
+ affs_unlock_dir(dir);
+ goto done;
+ }
+ mark_buffer_dirty_inode(bh, inode);
+
+ affs_unlock_dir(dir);
+ iput(dir);
+ } else {
+ link_bh = affs_bread(sb, link_ino);
+ if (!link_bh)
+ goto done;
+ }
+
+ while ((ino = be32_to_cpu(AFFS_TAIL(sb, bh)->link_chain)) != 0) {
+ if (ino == link_ino) {
+ __be32 ino2 = AFFS_TAIL(sb, link_bh)->link_chain;
+ AFFS_TAIL(sb, bh)->link_chain = ino2;
+ affs_adjust_checksum(bh, be32_to_cpu(ino2) - link_ino);
+ mark_buffer_dirty_inode(bh, inode);
+ retval = 0;
+ /* Fix the link count, if bh is a normal header block without links */
+ switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) {
+ case ST_LINKDIR:
+ case ST_LINKFILE:
+ break;
+ default:
+ if (!AFFS_TAIL(sb, bh)->link_chain)
+ set_nlink(inode, 1);
+ }
+ affs_free_block(sb, link_ino);
+ goto done;
+ }
+ affs_brelse(bh);
+ bh = affs_bread(sb, ino);
+ if (!bh)
+ goto done;
+ }
+ retval = -ENOENT;
+done:
+ affs_brelse(link_bh);
+ affs_brelse(bh);
+ return retval;
+}
+
+
+static int
+affs_empty_dir(struct inode *inode)
+{
+ struct super_block *sb = inode->i_sb;
+ struct buffer_head *bh;
+ int retval, size;
+
+ retval = -EIO;
+ bh = affs_bread(sb, inode->i_ino);
+ if (!bh)
+ goto done;
+
+ retval = -ENOTEMPTY;
+ for (size = AFFS_SB(sb)->s_hashsize - 1; size >= 0; size--)
+ if (AFFS_HEAD(bh)->table[size])
+ goto not_empty;
+ retval = 0;
+not_empty:
+ affs_brelse(bh);
+done:
+ return retval;
+}
+
+
+/* Remove a filesystem object. If the object to be removed has
+ * links to it, one of the links must be changed to inherit
+ * the file or directory. As above, any inode will do.
+ * The buffer will not be freed. If the header is a link, the
+ * block will be marked as free.
+ * This function returns a negative error number in case of
+ * an error, else 0 if the inode is to be deleted or 1 if not.
+ */
+
+int
+affs_remove_header(struct dentry *dentry)
+{
+ struct super_block *sb;
+ struct inode *inode, *dir;
+ struct buffer_head *bh = NULL;
+ int retval;
+
+ dir = d_inode(dentry->d_parent);
+ sb = dir->i_sb;
+
+ retval = -ENOENT;
+ inode = d_inode(dentry);
+ if (!inode)
+ goto done;
+
+ pr_debug("%s(key=%ld)\n", __func__, inode->i_ino);
+ retval = -EIO;
+ bh = affs_bread(sb, (u32)(long)dentry->d_fsdata);
+ if (!bh)
+ goto done;
+
+ affs_lock_link(inode);
+ affs_lock_dir(dir);
+ switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) {
+ case ST_USERDIR:
+ /* if we ever want to support links to dirs
+ * i_hash_lock of the inode must only be
+ * taken after some checks
+ */
+ affs_lock_dir(inode);
+ retval = affs_empty_dir(inode);
+ affs_unlock_dir(inode);
+ if (retval)
+ goto done_unlock;
+ break;
+ default:
+ break;
+ }
+
+ retval = affs_remove_hash(dir, bh);
+ if (retval)
+ goto done_unlock;
+ mark_buffer_dirty_inode(bh, inode);
+
+ affs_unlock_dir(dir);
+
+ if (inode->i_nlink > 1)
+ retval = affs_remove_link(dentry);
+ else
+ clear_nlink(inode);
+ affs_unlock_link(inode);
+ inode_set_ctime_current(inode);
+ mark_inode_dirty(inode);
+
+done:
+ affs_brelse(bh);
+ return retval;
+
+done_unlock:
+ affs_unlock_dir(dir);
+ affs_unlock_link(inode);
+ goto done;
+}
+
+/* Checksum a block, do various consistency checks and optionally return
+ the blocks type number. DATA points to the block. If their pointers
+ are non-null, *PTYPE and *STYPE are set to the primary and secondary
+ block types respectively, *HASHSIZE is set to the size of the hashtable
+ (which lets us calculate the block size).
+ Returns non-zero if the block is not consistent. */
+
+u32
+affs_checksum_block(struct super_block *sb, struct buffer_head *bh)
+{
+ __be32 *ptr = (__be32 *)bh->b_data;
+ u32 sum;
+ int bsize;
+
+ sum = 0;
+ for (bsize = sb->s_blocksize / sizeof(__be32); bsize > 0; bsize--)
+ sum += be32_to_cpu(*ptr++);
+ return sum;
+}
+
+/*
+ * Calculate the checksum of a disk block and store it
+ * at the indicated position.
+ */
+
+void
+affs_fix_checksum(struct super_block *sb, struct buffer_head *bh)
+{
+ int cnt = sb->s_blocksize / sizeof(__be32);
+ __be32 *ptr = (__be32 *)bh->b_data;
+ u32 checksum;
+ __be32 *checksumptr;
+
+ checksumptr = ptr + 5;
+ *checksumptr = 0;
+ for (checksum = 0; cnt > 0; ptr++, cnt--)
+ checksum += be32_to_cpu(*ptr);
+ *checksumptr = cpu_to_be32(-checksum);
+}
+
+void
+affs_secs_to_datestamp(time64_t secs, struct affs_date *ds)
+{
+ u32 days;
+ u32 minute;
+ s32 rem;
+
+ secs -= sys_tz.tz_minuteswest * 60 + AFFS_EPOCH_DELTA;
+ if (secs < 0)
+ secs = 0;
+ days = div_s64_rem(secs, 86400, &rem);
+ minute = rem / 60;
+ rem -= minute * 60;
+
+ ds->days = cpu_to_be32(days);
+ ds->mins = cpu_to_be32(minute);
+ ds->ticks = cpu_to_be32(rem * 50);
+}
+
+umode_t
+affs_prot_to_mode(u32 prot)
+{
+ umode_t mode = 0;
+
+ if (!(prot & FIBF_NOWRITE))
+ mode |= 0200;
+ if (!(prot & FIBF_NOREAD))
+ mode |= 0400;
+ if (!(prot & FIBF_NOEXECUTE))
+ mode |= 0100;
+ if (prot & FIBF_GRP_WRITE)
+ mode |= 0020;
+ if (prot & FIBF_GRP_READ)
+ mode |= 0040;
+ if (prot & FIBF_GRP_EXECUTE)
+ mode |= 0010;
+ if (prot & FIBF_OTR_WRITE)
+ mode |= 0002;
+ if (prot & FIBF_OTR_READ)
+ mode |= 0004;
+ if (prot & FIBF_OTR_EXECUTE)
+ mode |= 0001;
+
+ return mode;
+}
+
+void
+affs_mode_to_prot(struct inode *inode)
+{
+ u32 prot = AFFS_I(inode)->i_protect;
+ umode_t mode = inode->i_mode;
+
+ /*
+ * First, clear all RWED bits for owner, group, other.
+ * Then, recalculate them afresh.
+ *
+ * We'll always clear the delete-inhibit bit for the owner, as that is
+ * the classic single-user mode AmigaOS protection bit and we need to
+ * stay compatible with all scenarios.
+ *
+ * Since multi-user AmigaOS is an extension, we'll only set the
+ * delete-allow bit if any of the other bits in the same user class
+ * (group/other) are used.
+ */
+ prot &= ~(FIBF_NOEXECUTE | FIBF_NOREAD
+ | FIBF_NOWRITE | FIBF_NODELETE
+ | FIBF_GRP_EXECUTE | FIBF_GRP_READ
+ | FIBF_GRP_WRITE | FIBF_GRP_DELETE
+ | FIBF_OTR_EXECUTE | FIBF_OTR_READ
+ | FIBF_OTR_WRITE | FIBF_OTR_DELETE);
+
+ /* Classic single-user AmigaOS flags. These are inverted. */
+ if (!(mode & 0100))
+ prot |= FIBF_NOEXECUTE;
+ if (!(mode & 0400))
+ prot |= FIBF_NOREAD;
+ if (!(mode & 0200))
+ prot |= FIBF_NOWRITE;
+
+ /* Multi-user extended flags. Not inverted. */
+ if (mode & 0010)
+ prot |= FIBF_GRP_EXECUTE;
+ if (mode & 0040)
+ prot |= FIBF_GRP_READ;
+ if (mode & 0020)
+ prot |= FIBF_GRP_WRITE;
+ if (mode & 0070)
+ prot |= FIBF_GRP_DELETE;
+
+ if (mode & 0001)
+ prot |= FIBF_OTR_EXECUTE;
+ if (mode & 0004)
+ prot |= FIBF_OTR_READ;
+ if (mode & 0002)
+ prot |= FIBF_OTR_WRITE;
+ if (mode & 0007)
+ prot |= FIBF_OTR_DELETE;
+
+ AFFS_I(inode)->i_protect = prot;
+}
+
+void
+affs_error(struct super_block *sb, const char *function, const char *fmt, ...)
+{
+ struct va_format vaf;
+ va_list args;
+
+ va_start(args, fmt);
+ vaf.fmt = fmt;
+ vaf.va = &args;
+ pr_crit("error (device %s): %s(): %pV\n", sb->s_id, function, &vaf);
+ if (!sb_rdonly(sb))
+ pr_warn("Remounting filesystem read-only\n");
+ sb->s_flags |= SB_RDONLY;
+ va_end(args);
+}
+
+void
+affs_warning(struct super_block *sb, const char *function, const char *fmt, ...)
+{
+ struct va_format vaf;
+ va_list args;
+
+ va_start(args, fmt);
+ vaf.fmt = fmt;
+ vaf.va = &args;
+ pr_warn("(device %s): %s(): %pV\n", sb->s_id, function, &vaf);
+ va_end(args);
+}
+
+bool
+affs_nofilenametruncate(const struct dentry *dentry)
+{
+ return affs_test_opt(AFFS_SB(dentry->d_sb)->s_flags, SF_NO_TRUNCATE);
+}
+
+/* Check if the name is valid for a affs object. */
+
+int
+affs_check_name(const unsigned char *name, int len, bool notruncate)
+{
+ int i;
+
+ if (len > AFFSNAMEMAX) {
+ if (notruncate)
+ return -ENAMETOOLONG;
+ len = AFFSNAMEMAX;
+ }
+ for (i = 0; i < len; i++) {
+ if (name[i] < ' ' || name[i] == ':'
+ || (name[i] > 0x7e && name[i] < 0xa0))
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/* This function copies name to bstr, with at most 30
+ * characters length. The bstr will be prepended by
+ * a length byte.
+ * NOTE: The name will must be already checked by
+ * affs_check_name()!
+ */
+
+int
+affs_copy_name(unsigned char *bstr, struct dentry *dentry)
+{
+ u32 len = min(dentry->d_name.len, AFFSNAMEMAX);
+
+ *bstr++ = len;
+ memcpy(bstr, dentry->d_name.name, len);
+ return len;
+}
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