Adding upstream version 6.1.76.upstream/6.1.76upstream

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

1 files changed, 957 insertions, 0 deletions

diff --git a/fs/ufs/balloc.c b/fs/ufs/balloc.c
new file mode 100644
index 000000000..2436e3f82
--- /dev/null
+++ b/fs/ufs/balloc.c
@@ -0,0 +1,957 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/fs/ufs/balloc.c
+ *
+ * Copyright (C) 1998
+ * Daniel Pirkl <daniel.pirkl@email.cz>
+ * Charles University, Faculty of Mathematics and Physics
+ *
+ * UFS2 write support Evgeniy Dushistov <dushistov@mail.ru>, 2007
+ */
+
+#include <linux/fs.h>
+#include <linux/stat.h>
+#include <linux/time.h>
+#include <linux/string.h>
+#include <linux/buffer_head.h>
+#include <linux/capability.h>
+#include <linux/bitops.h>
+#include <linux/bio.h>
+#include <asm/byteorder.h>
+
+#include "ufs_fs.h"
+#include "ufs.h"
+#include "swab.h"
+#include "util.h"
+
+#define INVBLOCK ((u64)-1L)
+
+static u64 ufs_add_fragments(struct inode *, u64, unsigned, unsigned);
+static u64 ufs_alloc_fragments(struct inode *, unsigned, u64, unsigned, int *);
+static u64 ufs_alloccg_block(struct inode *, struct ufs_cg_private_info *, u64, int *);
+static u64 ufs_bitmap_search (struct super_block *, struct ufs_cg_private_info *, u64, unsigned);
+static unsigned char ufs_fragtable_8fpb[], ufs_fragtable_other[];
+static void ufs_clusteracct(struct super_block *, struct ufs_cg_private_info *, unsigned, int);
+
+/*
+ * Free 'count' fragments from fragment number 'fragment'
+ */
+void ufs_free_fragments(struct inode *inode, u64 fragment, unsigned count)
+{
+	struct super_block * sb;
+	struct ufs_sb_private_info * uspi;
+	struct ufs_cg_private_info * ucpi;
+	struct ufs_cylinder_group * ucg;
+	unsigned cgno, bit, end_bit, bbase, blkmap, i;
+	u64 blkno;
+	
+	sb = inode->i_sb;
+	uspi = UFS_SB(sb)->s_uspi;
+	
+	UFSD("ENTER, fragment %llu, count %u\n",
+	     (unsigned long long)fragment, count);
+	
+	if (ufs_fragnum(fragment) + count > uspi->s_fpg)
+		ufs_error (sb, "ufs_free_fragments", "internal error");
+
+	mutex_lock(&UFS_SB(sb)->s_lock);
+	
+	cgno = ufs_dtog(uspi, fragment);
+	bit = ufs_dtogd(uspi, fragment);
+	if (cgno >= uspi->s_ncg) {
+		ufs_panic (sb, "ufs_free_fragments", "freeing blocks are outside device");
+		goto failed;
+	}
+		
+	ucpi = ufs_load_cylinder (sb, cgno);
+	if (!ucpi) 
+		goto failed;
+	ucg = ubh_get_ucg (UCPI_UBH(ucpi));
+	if (!ufs_cg_chkmagic(sb, ucg)) {
+		ufs_panic (sb, "ufs_free_fragments", "internal error, bad magic number on cg %u", cgno);
+		goto failed;
+	}
+
+	end_bit = bit + count;
+	bbase = ufs_blknum (bit);
+	blkmap = ubh_blkmap (UCPI_UBH(ucpi), ucpi->c_freeoff, bbase);
+	ufs_fragacct (sb, blkmap, ucg->cg_frsum, -1);
+	for (i = bit; i < end_bit; i++) {
+		if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_freeoff, i))
+			ubh_setbit (UCPI_UBH(ucpi), ucpi->c_freeoff, i);
+		else 
+			ufs_error (sb, "ufs_free_fragments",
+				   "bit already cleared for fragment %u", i);
+	}
+
+	inode_sub_bytes(inode, count << uspi->s_fshift);
+	fs32_add(sb, &ucg->cg_cs.cs_nffree, count);
+	uspi->cs_total.cs_nffree += count;
+	fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, count);
+	blkmap = ubh_blkmap (UCPI_UBH(ucpi), ucpi->c_freeoff, bbase);
+	ufs_fragacct(sb, blkmap, ucg->cg_frsum, 1);
+
+	/*
+	 * Trying to reassemble free fragments into block
+	 */
+	blkno = ufs_fragstoblks (bbase);
+	if (ubh_isblockset(UCPI_UBH(ucpi), ucpi->c_freeoff, blkno)) {
+		fs32_sub(sb, &ucg->cg_cs.cs_nffree, uspi->s_fpb);
+		uspi->cs_total.cs_nffree -= uspi->s_fpb;
+		fs32_sub(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, uspi->s_fpb);
+		if ((UFS_SB(sb)->s_flags & UFS_CG_MASK) == UFS_CG_44BSD)
+			ufs_clusteracct (sb, ucpi, blkno, 1);
+		fs32_add(sb, &ucg->cg_cs.cs_nbfree, 1);
+		uspi->cs_total.cs_nbfree++;
+		fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nbfree, 1);
+		if (uspi->fs_magic != UFS2_MAGIC) {
+			unsigned cylno = ufs_cbtocylno (bbase);
+
+			fs16_add(sb, &ubh_cg_blks(ucpi, cylno,
+						  ufs_cbtorpos(bbase)), 1);
+			fs32_add(sb, &ubh_cg_blktot(ucpi, cylno), 1);
+		}
+	}
+	
+	ubh_mark_buffer_dirty (USPI_UBH(uspi));
+	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
+	if (sb->s_flags & SB_SYNCHRONOUS)
+		ubh_sync_block(UCPI_UBH(ucpi));
+	ufs_mark_sb_dirty(sb);
+
+	mutex_unlock(&UFS_SB(sb)->s_lock);
+	UFSD("EXIT\n");
+	return;
+
+failed:
+	mutex_unlock(&UFS_SB(sb)->s_lock);
+	UFSD("EXIT (FAILED)\n");
+	return;
+}
+
+/*
+ * Free 'count' fragments from fragment number 'fragment' (free whole blocks)
+ */
+void ufs_free_blocks(struct inode *inode, u64 fragment, unsigned count)
+{
+	struct super_block * sb;
+	struct ufs_sb_private_info * uspi;
+	struct ufs_cg_private_info * ucpi;
+	struct ufs_cylinder_group * ucg;
+	unsigned overflow, cgno, bit, end_bit, i;
+	u64 blkno;
+	
+	sb = inode->i_sb;
+	uspi = UFS_SB(sb)->s_uspi;
+
+	UFSD("ENTER, fragment %llu, count %u\n",
+	     (unsigned long long)fragment, count);
+	
+	if ((fragment & uspi->s_fpbmask) || (count & uspi->s_fpbmask)) {
+		ufs_error (sb, "ufs_free_blocks", "internal error, "
+			   "fragment %llu, count %u\n",
+			   (unsigned long long)fragment, count);
+		goto failed;
+	}
+
+	mutex_lock(&UFS_SB(sb)->s_lock);
+	
+do_more:
+	overflow = 0;
+	cgno = ufs_dtog(uspi, fragment);
+	bit = ufs_dtogd(uspi, fragment);
+	if (cgno >= uspi->s_ncg) {
+		ufs_panic (sb, "ufs_free_blocks", "freeing blocks are outside device");
+		goto failed_unlock;
+	}
+	end_bit = bit + count;
+	if (end_bit > uspi->s_fpg) {
+		overflow = bit + count - uspi->s_fpg;
+		count -= overflow;
+		end_bit -= overflow;
+	}
+
+	ucpi = ufs_load_cylinder (sb, cgno);
+	if (!ucpi) 
+		goto failed_unlock;
+	ucg = ubh_get_ucg (UCPI_UBH(ucpi));
+	if (!ufs_cg_chkmagic(sb, ucg)) {
+		ufs_panic (sb, "ufs_free_blocks", "internal error, bad magic number on cg %u", cgno);
+		goto failed_unlock;
+	}
+
+	for (i = bit; i < end_bit; i += uspi->s_fpb) {
+		blkno = ufs_fragstoblks(i);
+		if (ubh_isblockset(UCPI_UBH(ucpi), ucpi->c_freeoff, blkno)) {
+			ufs_error(sb, "ufs_free_blocks", "freeing free fragment");
+		}
+		ubh_setblock(UCPI_UBH(ucpi), ucpi->c_freeoff, blkno);
+		inode_sub_bytes(inode, uspi->s_fpb << uspi->s_fshift);
+		if ((UFS_SB(sb)->s_flags & UFS_CG_MASK) == UFS_CG_44BSD)
+			ufs_clusteracct (sb, ucpi, blkno, 1);
+
+		fs32_add(sb, &ucg->cg_cs.cs_nbfree, 1);
+		uspi->cs_total.cs_nbfree++;
+		fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nbfree, 1);
+
+		if (uspi->fs_magic != UFS2_MAGIC) {
+			unsigned cylno = ufs_cbtocylno(i);
+
+			fs16_add(sb, &ubh_cg_blks(ucpi, cylno,
+						  ufs_cbtorpos(i)), 1);
+			fs32_add(sb, &ubh_cg_blktot(ucpi, cylno), 1);
+		}
+	}
+
+	ubh_mark_buffer_dirty (USPI_UBH(uspi));
+	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
+	if (sb->s_flags & SB_SYNCHRONOUS)
+		ubh_sync_block(UCPI_UBH(ucpi));
+
+	if (overflow) {
+		fragment += count;
+		count = overflow;
+		goto do_more;
+	}
+
+	ufs_mark_sb_dirty(sb);
+	mutex_unlock(&UFS_SB(sb)->s_lock);
+	UFSD("EXIT\n");
+	return;
+
+failed_unlock:
+	mutex_unlock(&UFS_SB(sb)->s_lock);
+failed:
+	UFSD("EXIT (FAILED)\n");
+	return;
+}
+
+/*
+ * Modify inode page cache in such way:
+ * have - blocks with b_blocknr equal to oldb...oldb+count-1
+ * get - blocks with b_blocknr equal to newb...newb+count-1
+ * also we suppose that oldb...oldb+count-1 blocks
+ * situated at the end of file.
+ *
+ * We can come here from ufs_writepage or ufs_prepare_write,
+ * locked_page is argument of these functions, so we already lock it.
+ */
+static void ufs_change_blocknr(struct inode *inode, sector_t beg,
+			       unsigned int count, sector_t oldb,
+			       sector_t newb, struct page *locked_page)
+{
+	const unsigned blks_per_page =
+		1 << (PAGE_SHIFT - inode->i_blkbits);
+	const unsigned mask = blks_per_page - 1;
+	struct address_space * const mapping = inode->i_mapping;
+	pgoff_t index, cur_index, last_index;
+	unsigned pos, j, lblock;
+	sector_t end, i;
+	struct page *page;
+	struct buffer_head *head, *bh;
+
+	UFSD("ENTER, ino %lu, count %u, oldb %llu, newb %llu\n",
+	      inode->i_ino, count,
+	     (unsigned long long)oldb, (unsigned long long)newb);
+
+	BUG_ON(!locked_page);
+	BUG_ON(!PageLocked(locked_page));
+
+	cur_index = locked_page->index;
+	end = count + beg;
+	last_index = end >> (PAGE_SHIFT - inode->i_blkbits);
+	for (i = beg; i < end; i = (i | mask) + 1) {
+		index = i >> (PAGE_SHIFT - inode->i_blkbits);
+
+		if (likely(cur_index != index)) {
+			page = ufs_get_locked_page(mapping, index);
+			if (!page)/* it was truncated */
+				continue;
+			if (IS_ERR(page)) {/* or EIO */
+				ufs_error(inode->i_sb, __func__,
+					  "read of page %llu failed\n",
+					  (unsigned long long)index);
+				continue;
+			}
+		} else
+			page = locked_page;
+
+		head = page_buffers(page);
+		bh = head;
+		pos = i & mask;
+		for (j = 0; j < pos; ++j)
+			bh = bh->b_this_page;
+
+
+		if (unlikely(index == last_index))
+			lblock = end & mask;
+		else
+			lblock = blks_per_page;
+
+		do {
+			if (j >= lblock)
+				break;
+			pos = (i - beg) + j;
+
+			if (!buffer_mapped(bh))
+					map_bh(bh, inode->i_sb, oldb + pos);
+			if (bh_read(bh, 0) < 0) {
+				ufs_error(inode->i_sb, __func__,
+					  "read of block failed\n");
+				break;
+			}
+
+			UFSD(" change from %llu to %llu, pos %u\n",
+			     (unsigned long long)(pos + oldb),
+			     (unsigned long long)(pos + newb), pos);
+
+			bh->b_blocknr = newb + pos;
+			clean_bdev_bh_alias(bh);
+			mark_buffer_dirty(bh);
+			++j;
+			bh = bh->b_this_page;
+		} while (bh != head);
+
+		if (likely(cur_index != index))
+			ufs_put_locked_page(page);
+ 	}
+	UFSD("EXIT\n");
+}
+
+static void ufs_clear_frags(struct inode *inode, sector_t beg, unsigned int n,
+			    int sync)
+{
+	struct buffer_head *bh;
+	sector_t end = beg + n;
+
+	for (; beg < end; ++beg) {
+		bh = sb_getblk(inode->i_sb, beg);
+		lock_buffer(bh);
+		memset(bh->b_data, 0, inode->i_sb->s_blocksize);
+		set_buffer_uptodate(bh);
+		mark_buffer_dirty(bh);
+		unlock_buffer(bh);
+		if (IS_SYNC(inode) || sync)
+			sync_dirty_buffer(bh);
+		brelse(bh);
+	}
+}
+
+u64 ufs_new_fragments(struct inode *inode, void *p, u64 fragment,
+			   u64 goal, unsigned count, int *err,
+			   struct page *locked_page)
+{
+	struct super_block * sb;
+	struct ufs_sb_private_info * uspi;
+	struct ufs_super_block_first * usb1;
+	unsigned cgno, oldcount, newcount;
+	u64 tmp, request, result;
+	
+	UFSD("ENTER, ino %lu, fragment %llu, goal %llu, count %u\n",
+	     inode->i_ino, (unsigned long long)fragment,
+	     (unsigned long long)goal, count);
+	
+	sb = inode->i_sb;
+	uspi = UFS_SB(sb)->s_uspi;
+	usb1 = ubh_get_usb_first(uspi);
+	*err = -ENOSPC;
+
+	mutex_lock(&UFS_SB(sb)->s_lock);
+	tmp = ufs_data_ptr_to_cpu(sb, p);
+
+	if (count + ufs_fragnum(fragment) > uspi->s_fpb) {
+		ufs_warning(sb, "ufs_new_fragments", "internal warning"
+			    " fragment %llu, count %u",
+			    (unsigned long long)fragment, count);
+		count = uspi->s_fpb - ufs_fragnum(fragment); 
+	}
+	oldcount = ufs_fragnum (fragment);
+	newcount = oldcount + count;
+
+	/*
+	 * Somebody else has just allocated our fragments
+	 */
+	if (oldcount) {
+		if (!tmp) {
+			ufs_error(sb, "ufs_new_fragments", "internal error, "
+				  "fragment %llu, tmp %llu\n",
+				  (unsigned long long)fragment,
+				  (unsigned long long)tmp);
+			mutex_unlock(&UFS_SB(sb)->s_lock);
+			return INVBLOCK;
+		}
+		if (fragment < UFS_I(inode)->i_lastfrag) {
+			UFSD("EXIT (ALREADY ALLOCATED)\n");
+			mutex_unlock(&UFS_SB(sb)->s_lock);
+			return 0;
+		}
+	}
+	else {
+		if (tmp) {
+			UFSD("EXIT (ALREADY ALLOCATED)\n");
+			mutex_unlock(&UFS_SB(sb)->s_lock);
+			return 0;
+		}
+	}
+
+	/*
+	 * There is not enough space for user on the device
+	 */
+	if (unlikely(ufs_freefrags(uspi) <= uspi->s_root_blocks)) {
+		if (!capable(CAP_SYS_RESOURCE)) {
+			mutex_unlock(&UFS_SB(sb)->s_lock);
+			UFSD("EXIT (FAILED)\n");
+			return 0;
+		}
+	}
+
+	if (goal >= uspi->s_size) 
+		goal = 0;
+	if (goal == 0) 
+		cgno = ufs_inotocg (inode->i_ino);
+	else
+		cgno = ufs_dtog(uspi, goal);
+	 
+	/*
+	 * allocate new fragment
+	 */
+	if (oldcount == 0) {
+		result = ufs_alloc_fragments (inode, cgno, goal, count, err);
+		if (result) {
+			ufs_clear_frags(inode, result + oldcount,
+					newcount - oldcount, locked_page != NULL);
+			*err = 0;
+			write_seqlock(&UFS_I(inode)->meta_lock);
+			ufs_cpu_to_data_ptr(sb, p, result);
+			UFS_I(inode)->i_lastfrag =
+				max(UFS_I(inode)->i_lastfrag, fragment + count);
+			write_sequnlock(&UFS_I(inode)->meta_lock);
+		}
+		mutex_unlock(&UFS_SB(sb)->s_lock);
+		UFSD("EXIT, result %llu\n", (unsigned long long)result);
+		return result;
+	}
+
+	/*
+	 * resize block
+	 */
+	result = ufs_add_fragments(inode, tmp, oldcount, newcount);
+	if (result) {
+		*err = 0;
+		read_seqlock_excl(&UFS_I(inode)->meta_lock);
+		UFS_I(inode)->i_lastfrag = max(UFS_I(inode)->i_lastfrag,
+						fragment + count);
+		read_sequnlock_excl(&UFS_I(inode)->meta_lock);
+		ufs_clear_frags(inode, result + oldcount, newcount - oldcount,
+				locked_page != NULL);
+		mutex_unlock(&UFS_SB(sb)->s_lock);
+		UFSD("EXIT, result %llu\n", (unsigned long long)result);
+		return result;
+	}
+
+	/*
+	 * allocate new block and move data
+	 */
+	if (fs32_to_cpu(sb, usb1->fs_optim) == UFS_OPTSPACE) {
+		request = newcount;
+		if (uspi->cs_total.cs_nffree < uspi->s_space_to_time)
+			usb1->fs_optim = cpu_to_fs32(sb, UFS_OPTTIME);
+	} else {
+		request = uspi->s_fpb;
+		if (uspi->cs_total.cs_nffree > uspi->s_time_to_space)
+			usb1->fs_optim = cpu_to_fs32(sb, UFS_OPTSPACE);
+	}
+	result = ufs_alloc_fragments (inode, cgno, goal, request, err);
+	if (result) {
+		ufs_clear_frags(inode, result + oldcount, newcount - oldcount,
+				locked_page != NULL);
+		mutex_unlock(&UFS_SB(sb)->s_lock);
+		ufs_change_blocknr(inode, fragment - oldcount, oldcount,
+				   uspi->s_sbbase + tmp,
+				   uspi->s_sbbase + result, locked_page);
+		*err = 0;
+		write_seqlock(&UFS_I(inode)->meta_lock);
+		ufs_cpu_to_data_ptr(sb, p, result);
+		UFS_I(inode)->i_lastfrag = max(UFS_I(inode)->i_lastfrag,
+						fragment + count);
+		write_sequnlock(&UFS_I(inode)->meta_lock);
+		if (newcount < request)
+			ufs_free_fragments (inode, result + newcount, request - newcount);
+		ufs_free_fragments (inode, tmp, oldcount);
+		UFSD("EXIT, result %llu\n", (unsigned long long)result);
+		return result;
+	}
+
+	mutex_unlock(&UFS_SB(sb)->s_lock);
+	UFSD("EXIT (FAILED)\n");
+	return 0;
+}		
+
+static bool try_add_frags(struct inode *inode, unsigned frags)
+{
+	unsigned size = frags * i_blocksize(inode);
+	spin_lock(&inode->i_lock);
+	__inode_add_bytes(inode, size);
+	if (unlikely((u32)inode->i_blocks != inode->i_blocks)) {
+		__inode_sub_bytes(inode, size);
+		spin_unlock(&inode->i_lock);
+		return false;
+	}
+	spin_unlock(&inode->i_lock);
+	return true;
+}
+
+static u64 ufs_add_fragments(struct inode *inode, u64 fragment,
+			     unsigned oldcount, unsigned newcount)
+{
+	struct super_block * sb;
+	struct ufs_sb_private_info * uspi;
+	struct ufs_cg_private_info * ucpi;
+	struct ufs_cylinder_group * ucg;
+	unsigned cgno, fragno, fragoff, count, fragsize, i;
+	
+	UFSD("ENTER, fragment %llu, oldcount %u, newcount %u\n",
+	     (unsigned long long)fragment, oldcount, newcount);
+	
+	sb = inode->i_sb;
+	uspi = UFS_SB(sb)->s_uspi;
+	count = newcount - oldcount;
+	
+	cgno = ufs_dtog(uspi, fragment);
+	if (fs32_to_cpu(sb, UFS_SB(sb)->fs_cs(cgno).cs_nffree) < count)
+		return 0;
+	if ((ufs_fragnum (fragment) + newcount) > uspi->s_fpb)
+		return 0;
+	ucpi = ufs_load_cylinder (sb, cgno);
+	if (!ucpi)
+		return 0;
+	ucg = ubh_get_ucg (UCPI_UBH(ucpi));
+	if (!ufs_cg_chkmagic(sb, ucg)) {
+		ufs_panic (sb, "ufs_add_fragments",
+			"internal error, bad magic number on cg %u", cgno);
+		return 0;
+	}
+
+	fragno = ufs_dtogd(uspi, fragment);
+	fragoff = ufs_fragnum (fragno);
+	for (i = oldcount; i < newcount; i++)
+		if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_freeoff, fragno + i))
+			return 0;
+
+	if (!try_add_frags(inode, count))
+		return 0;
+	/*
+	 * Block can be extended
+	 */
+	ucg->cg_time = ufs_get_seconds(sb);
+	for (i = newcount; i < (uspi->s_fpb - fragoff); i++)
+		if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_freeoff, fragno + i))
+			break;
+	fragsize = i - oldcount;
+	if (!fs32_to_cpu(sb, ucg->cg_frsum[fragsize]))
+		ufs_panic (sb, "ufs_add_fragments",
+			"internal error or corrupted bitmap on cg %u", cgno);
+	fs32_sub(sb, &ucg->cg_frsum[fragsize], 1);
+	if (fragsize != count)
+		fs32_add(sb, &ucg->cg_frsum[fragsize - count], 1);
+	for (i = oldcount; i < newcount; i++)
+		ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_freeoff, fragno + i);
+
+	fs32_sub(sb, &ucg->cg_cs.cs_nffree, count);
+	fs32_sub(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, count);
+	uspi->cs_total.cs_nffree -= count;
+	
+	ubh_mark_buffer_dirty (USPI_UBH(uspi));
+	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
+	if (sb->s_flags & SB_SYNCHRONOUS)
+		ubh_sync_block(UCPI_UBH(ucpi));
+	ufs_mark_sb_dirty(sb);
+
+	UFSD("EXIT, fragment %llu\n", (unsigned long long)fragment);
+	
+	return fragment;
+}
+
+#define UFS_TEST_FREE_SPACE_CG \
+	ucg = (struct ufs_cylinder_group *) UFS_SB(sb)->s_ucg[cgno]->b_data; \
+	if (fs32_to_cpu(sb, ucg->cg_cs.cs_nbfree)) \
+		goto cg_found; \
+	for (k = count; k < uspi->s_fpb; k++) \
+		if (fs32_to_cpu(sb, ucg->cg_frsum[k])) \
+			goto cg_found; 
+
+static u64 ufs_alloc_fragments(struct inode *inode, unsigned cgno,
+			       u64 goal, unsigned count, int *err)
+{
+	struct super_block * sb;
+	struct ufs_sb_private_info * uspi;
+	struct ufs_cg_private_info * ucpi;
+	struct ufs_cylinder_group * ucg;
+	unsigned oldcg, i, j, k, allocsize;
+	u64 result;
+	
+	UFSD("ENTER, ino %lu, cgno %u, goal %llu, count %u\n",
+	     inode->i_ino, cgno, (unsigned long long)goal, count);
+
+	sb = inode->i_sb;
+	uspi = UFS_SB(sb)->s_uspi;
+	oldcg = cgno;
+	
+	/*
+	 * 1. searching on preferred cylinder group
+	 */
+	UFS_TEST_FREE_SPACE_CG
+
+	/*
+	 * 2. quadratic rehash
+	 */
+	for (j = 1; j < uspi->s_ncg; j *= 2) {
+		cgno += j;
+		if (cgno >= uspi->s_ncg) 
+			cgno -= uspi->s_ncg;
+		UFS_TEST_FREE_SPACE_CG
+	}
+
+	/*
+	 * 3. brute force search
+	 * We start at i = 2 ( 0 is checked at 1.step, 1 at 2.step )
+	 */
+	cgno = (oldcg + 1) % uspi->s_ncg;
+	for (j = 2; j < uspi->s_ncg; j++) {
+		cgno++;
+		if (cgno >= uspi->s_ncg)
+			cgno = 0;
+		UFS_TEST_FREE_SPACE_CG
+	}
+	
+	UFSD("EXIT (FAILED)\n");
+	return 0;
+
+cg_found:
+	ucpi = ufs_load_cylinder (sb, cgno);
+	if (!ucpi)
+		return 0;
+	ucg = ubh_get_ucg (UCPI_UBH(ucpi));
+	if (!ufs_cg_chkmagic(sb, ucg)) 
+		ufs_panic (sb, "ufs_alloc_fragments",
+			"internal error, bad magic number on cg %u", cgno);
+	ucg->cg_time = ufs_get_seconds(sb);
+
+	if (count == uspi->s_fpb) {
+		result = ufs_alloccg_block (inode, ucpi, goal, err);
+		if (result == INVBLOCK)
+			return 0;
+		goto succed;
+	}
+
+	for (allocsize = count; allocsize < uspi->s_fpb; allocsize++)
+		if (fs32_to_cpu(sb, ucg->cg_frsum[allocsize]) != 0)
+			break;
+	
+	if (allocsize == uspi->s_fpb) {
+		result = ufs_alloccg_block (inode, ucpi, goal, err);
+		if (result == INVBLOCK)
+			return 0;
+		goal = ufs_dtogd(uspi, result);
+		for (i = count; i < uspi->s_fpb; i++)
+			ubh_setbit (UCPI_UBH(ucpi), ucpi->c_freeoff, goal + i);
+		i = uspi->s_fpb - count;
+
+		inode_sub_bytes(inode, i << uspi->s_fshift);
+		fs32_add(sb, &ucg->cg_cs.cs_nffree, i);
+		uspi->cs_total.cs_nffree += i;
+		fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, i);
+		fs32_add(sb, &ucg->cg_frsum[i], 1);
+		goto succed;
+	}
+
+	result = ufs_bitmap_search (sb, ucpi, goal, allocsize);
+	if (result == INVBLOCK)
+		return 0;
+	if (!try_add_frags(inode, count))
+		return 0;
+	for (i = 0; i < count; i++)
+		ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_freeoff, result + i);
+	
+	fs32_sub(sb, &ucg->cg_cs.cs_nffree, count);
+	uspi->cs_total.cs_nffree -= count;
+	fs32_sub(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, count);
+	fs32_sub(sb, &ucg->cg_frsum[allocsize], 1);
+
+	if (count != allocsize)
+		fs32_add(sb, &ucg->cg_frsum[allocsize - count], 1);
+
+succed:
+	ubh_mark_buffer_dirty (USPI_UBH(uspi));
+	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
+	if (sb->s_flags & SB_SYNCHRONOUS)
+		ubh_sync_block(UCPI_UBH(ucpi));
+	ufs_mark_sb_dirty(sb);
+
+	result += cgno * uspi->s_fpg;
+	UFSD("EXIT3, result %llu\n", (unsigned long long)result);
+	return result;
+}
+
+static u64 ufs_alloccg_block(struct inode *inode,
+			     struct ufs_cg_private_info *ucpi,
+			     u64 goal, int *err)
+{
+	struct super_block * sb;
+	struct ufs_sb_private_info * uspi;
+	struct ufs_cylinder_group * ucg;
+	u64 result, blkno;
+
+	UFSD("ENTER, goal %llu\n", (unsigned long long)goal);
+
+	sb = inode->i_sb;
+	uspi = UFS_SB(sb)->s_uspi;
+	ucg = ubh_get_ucg(UCPI_UBH(ucpi));
+
+	if (goal == 0) {
+		goal = ucpi->c_rotor;
+		goto norot;
+	}
+	goal = ufs_blknum (goal);
+	goal = ufs_dtogd(uspi, goal);
+	
+	/*
+	 * If the requested block is available, use it.
+	 */
+	if (ubh_isblockset(UCPI_UBH(ucpi), ucpi->c_freeoff, ufs_fragstoblks(goal))) {
+		result = goal;
+		goto gotit;
+	}
+	
+norot:	
+	result = ufs_bitmap_search (sb, ucpi, goal, uspi->s_fpb);
+	if (result == INVBLOCK)
+		return INVBLOCK;
+	ucpi->c_rotor = result;
+gotit:
+	if (!try_add_frags(inode, uspi->s_fpb))
+		return 0;
+	blkno = ufs_fragstoblks(result);
+	ubh_clrblock (UCPI_UBH(ucpi), ucpi->c_freeoff, blkno);
+	if ((UFS_SB(sb)->s_flags & UFS_CG_MASK) == UFS_CG_44BSD)
+		ufs_clusteracct (sb, ucpi, blkno, -1);
+
+	fs32_sub(sb, &ucg->cg_cs.cs_nbfree, 1);
+	uspi->cs_total.cs_nbfree--;
+	fs32_sub(sb, &UFS_SB(sb)->fs_cs(ucpi->c_cgx).cs_nbfree, 1);
+
+	if (uspi->fs_magic != UFS2_MAGIC) {
+		unsigned cylno = ufs_cbtocylno((unsigned)result);
+
+		fs16_sub(sb, &ubh_cg_blks(ucpi, cylno,
+					  ufs_cbtorpos((unsigned)result)), 1);
+		fs32_sub(sb, &ubh_cg_blktot(ucpi, cylno), 1);
+	}
+	
+	UFSD("EXIT, result %llu\n", (unsigned long long)result);
+
+	return result;
+}
+
+static unsigned ubh_scanc(struct ufs_sb_private_info *uspi,
+			  struct ufs_buffer_head *ubh,
+			  unsigned begin, unsigned size,
+			  unsigned char *table, unsigned char mask)
+{
+	unsigned rest, offset;
+	unsigned char *cp;
+	
+
+	offset = begin & ~uspi->s_fmask;
+	begin >>= uspi->s_fshift;
+	for (;;) {
+		if ((offset + size) < uspi->s_fsize)
+			rest = size;
+		else
+			rest = uspi->s_fsize - offset;
+		size -= rest;
+		cp = ubh->bh[begin]->b_data + offset;
+		while ((table[*cp++] & mask) == 0 && --rest)
+			;
+		if (rest || !size)
+			break;
+		begin++;
+		offset = 0;
+	}
+	return (size + rest);
+}
+
+/*
+ * Find a block of the specified size in the specified cylinder group.
+ * @sp: pointer to super block
+ * @ucpi: pointer to cylinder group info
+ * @goal: near which block we want find new one
+ * @count: specified size
+ */
+static u64 ufs_bitmap_search(struct super_block *sb,
+			     struct ufs_cg_private_info *ucpi,
+			     u64 goal, unsigned count)
+{
+	/*
+	 * Bit patterns for identifying fragments in the block map
+	 * used as ((map & mask_arr) == want_arr)
+	 */
+	static const int mask_arr[9] = {
+		0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f, 0xff, 0x1ff, 0x3ff
+	};
+	static const int want_arr[9] = {
+		0x0, 0x2, 0x6, 0xe, 0x1e, 0x3e, 0x7e, 0xfe, 0x1fe
+	};
+	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
+	unsigned start, length, loc;
+	unsigned pos, want, blockmap, mask, end;
+	u64 result;
+
+	UFSD("ENTER, cg %u, goal %llu, count %u\n", ucpi->c_cgx,
+	     (unsigned long long)goal, count);
+
+	if (goal)
+		start = ufs_dtogd(uspi, goal) >> 3;
+	else
+		start = ucpi->c_frotor >> 3;
+		
+	length = ((uspi->s_fpg + 7) >> 3) - start;
+	loc = ubh_scanc(uspi, UCPI_UBH(ucpi), ucpi->c_freeoff + start, length,
+		(uspi->s_fpb == 8) ? ufs_fragtable_8fpb : ufs_fragtable_other,
+		1 << (count - 1 + (uspi->s_fpb & 7))); 
+	if (loc == 0) {
+		length = start + 1;
+		loc = ubh_scanc(uspi, UCPI_UBH(ucpi), ucpi->c_freeoff, length,
+				(uspi->s_fpb == 8) ? ufs_fragtable_8fpb :
+				ufs_fragtable_other,
+				1 << (count - 1 + (uspi->s_fpb & 7)));
+		if (loc == 0) {
+			ufs_error(sb, "ufs_bitmap_search",
+				  "bitmap corrupted on cg %u, start %u,"
+				  " length %u, count %u, freeoff %u\n",
+				  ucpi->c_cgx, start, length, count,
+				  ucpi->c_freeoff);
+			return INVBLOCK;
+		}
+		start = 0;
+	}
+	result = (start + length - loc) << 3;
+	ucpi->c_frotor = result;
+
+	/*
+	 * found the byte in the map
+	 */
+
+	for (end = result + 8; result < end; result += uspi->s_fpb) {
+		blockmap = ubh_blkmap(UCPI_UBH(ucpi), ucpi->c_freeoff, result);
+		blockmap <<= 1;
+		mask = mask_arr[count];
+		want = want_arr[count];
+		for (pos = 0; pos <= uspi->s_fpb - count; pos++) {
+			if ((blockmap & mask) == want) {
+				UFSD("EXIT, result %llu\n",
+				     (unsigned long long)result);
+				return result + pos;
+ 			}
+			mask <<= 1;
+			want <<= 1;
+ 		}
+ 	}
+
+	ufs_error(sb, "ufs_bitmap_search", "block not in map on cg %u\n",
+		  ucpi->c_cgx);
+	UFSD("EXIT (FAILED)\n");
+	return INVBLOCK;
+}
+
+static void ufs_clusteracct(struct super_block * sb,
+	struct ufs_cg_private_info * ucpi, unsigned blkno, int cnt)
+{
+	struct ufs_sb_private_info * uspi;
+	int i, start, end, forw, back;
+	
+	uspi = UFS_SB(sb)->s_uspi;
+	if (uspi->s_contigsumsize <= 0)
+		return;
+
+	if (cnt > 0)
+		ubh_setbit(UCPI_UBH(ucpi), ucpi->c_clusteroff, blkno);
+	else
+		ubh_clrbit(UCPI_UBH(ucpi), ucpi->c_clusteroff, blkno);
+
+	/*
+	 * Find the size of the cluster going forward.
+	 */
+	start = blkno + 1;
+	end = start + uspi->s_contigsumsize;
+	if ( end >= ucpi->c_nclusterblks)
+		end = ucpi->c_nclusterblks;
+	i = ubh_find_next_zero_bit (UCPI_UBH(ucpi), ucpi->c_clusteroff, end, start);
+	if (i > end)
+		i = end;
+	forw = i - start;
+	
+	/*
+	 * Find the size of the cluster going backward.
+	 */
+	start = blkno - 1;
+	end = start - uspi->s_contigsumsize;
+	if (end < 0 ) 
+		end = -1;
+	i = ubh_find_last_zero_bit (UCPI_UBH(ucpi), ucpi->c_clusteroff, start, end);
+	if ( i < end) 
+		i = end;
+	back = start - i;
+	
+	/*
+	 * Account for old cluster and the possibly new forward and
+	 * back clusters.
+	 */
+	i = back + forw + 1;
+	if (i > uspi->s_contigsumsize)
+		i = uspi->s_contigsumsize;
+	fs32_add(sb, (__fs32*)ubh_get_addr(UCPI_UBH(ucpi), ucpi->c_clustersumoff + (i << 2)), cnt);
+	if (back > 0)
+		fs32_sub(sb, (__fs32*)ubh_get_addr(UCPI_UBH(ucpi), ucpi->c_clustersumoff + (back << 2)), cnt);
+	if (forw > 0)
+		fs32_sub(sb, (__fs32*)ubh_get_addr(UCPI_UBH(ucpi), ucpi->c_clustersumoff + (forw << 2)), cnt);
+}
+
+
+static unsigned char ufs_fragtable_8fpb[] = {
+	0x00, 0x01, 0x01, 0x02, 0x01, 0x01, 0x02, 0x04, 0x01, 0x01, 0x01, 0x03, 0x02, 0x03, 0x04, 0x08,
+	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x02, 0x03, 0x03, 0x02, 0x04, 0x05, 0x08, 0x10,
+	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
+	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 0x04, 0x05, 0x05, 0x06, 0x08, 0x09, 0x10, 0x20,
+	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,	
+	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11,
+	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0A,
+	0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04, 0x08, 0x09, 0x09, 0x0A, 0x10, 0x11, 0x20, 0x40,
+	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
+	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11,
+	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
+	0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07, 0x05, 0x05, 0x05, 0x07, 0x09, 0x09, 0x11, 0x21,
+	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0A,
+	0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07, 0x02, 0x03, 0x03, 0x02, 0x06, 0x07, 0x0A, 0x12,
+	0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04, 0x05, 0x05, 0x05, 0x07, 0x06, 0x07, 0x04, 0x0C,
+	0x08, 0x09, 0x09, 0x0A, 0x09, 0x09, 0x0A, 0x0C, 0x10, 0x11, 0x11, 0x12, 0x20, 0x21, 0x40, 0x80,
+};
+
+static unsigned char ufs_fragtable_other[] = {
+	0x00, 0x16, 0x16, 0x2A, 0x16, 0x16, 0x26, 0x4E, 0x16, 0x16, 0x16, 0x3E, 0x2A, 0x3E, 0x4E, 0x8A,
+	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
+	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
+	0x2A, 0x3E, 0x3E, 0x2A, 0x3E, 0x3E, 0x2E, 0x6E, 0x3E, 0x3E, 0x3E, 0x3E, 0x2A, 0x3E, 0x6E, 0xAA,
+	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
+	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
+	0x26, 0x36, 0x36, 0x2E, 0x36, 0x36, 0x26, 0x6E, 0x36, 0x36, 0x36, 0x3E, 0x2E, 0x3E, 0x6E, 0xAE,
+	0x4E, 0x5E, 0x5E, 0x6E, 0x5E, 0x5E, 0x6E, 0x4E, 0x5E, 0x5E, 0x5E, 0x7E, 0x6E, 0x7E, 0x4E, 0xCE,
+	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
+	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
+	0x16, 0x16, 0x16, 0x3E, 0x16, 0x16, 0x36, 0x5E, 0x16, 0x16, 0x16, 0x3E, 0x3E, 0x3E, 0x5E, 0x9E,
+	0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E, 0xBE,
+	0x2A, 0x3E, 0x3E, 0x2A, 0x3E, 0x3E, 0x2E, 0x6E, 0x3E, 0x3E, 0x3E, 0x3E, 0x2A, 0x3E, 0x6E, 0xAA,
+	0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E,	0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x3E, 0x7E, 0xBE,
+	0x4E, 0x5E, 0x5E, 0x6E, 0x5E, 0x5E, 0x6E, 0x4E, 0x5E, 0x5E, 0x5E, 0x7E, 0x6E, 0x7E, 0x4E, 0xCE,
+	0x8A, 0x9E, 0x9E, 0xAA, 0x9E, 0x9E, 0xAE, 0xCE, 0x9E, 0x9E, 0x9E, 0xBE, 0xAA, 0xBE, 0xCE, 0x8A,
+};