Here's an updated patch for 2.6.23.13 that fixes a problem introduced due to
patching that I discovered while testing the 2.6.23.13 change I sent out earlier
today (the -mm tree patch does not suffer from this problem).
Thanks,
Abhishek
Signed-off-by: Abhishek Rai <[email protected]>
diff -rupdN linux-2.6.23.13-clean/fs/ext3/balloc.c linux-2.6.23.13-ext3mc/fs/ext3/balloc.c
--- linux-2.6.23.13-clean/fs/ext3/balloc.c 2008-01-09 12:18:17.000000000 -0500
+++ linux-2.6.23.13-ext3mc/fs/ext3/balloc.c 2008-01-12 23:59:36.000000000 -0500
@@ -33,6 +33,29 @@
* super block. Each descriptor contains the number of the bitmap block and
* the free blocks count in the block. The descriptors are loaded in memory
* when a file system is mounted (see ext3_fill_super).
+ *
+ * A note on ext3 metaclustering:
+ *
+ * Start of End of
+ * block group block group
+ * ________________________________________________________________
+ * | NON-MC REGION | MC REGION |
+ * | |Overflow |
+ * |Data blocks and |data Indirect |
+ * |overflow indirect blocks |blocks blocks |
+ * |----------> |-------> <--------|
+ * |________________________________________________________________|
+ *
+ * Every block group has at its end a semi-reserved region called the
+ * metacluster mostly used for allocating indirect blocks. Under normal
+ * circumstances, the metacluster is used only for allocating indirect
+ * blocks which are allocated in decreasing order of block numbers.
+ * The non-Metacluster region is used for data block allocation which are
+ * allocated in increasing order of block numbers. However, when the MC
+ * runs out of space, indirect blocks can be allocated in the non-MC
+ * region along with the data blocks in the forward direction. Similarly,
+ * when non-MC runs out of space, new data blocks are allocated in MC but
+ * in the forward direction.
*/
@@ -108,6 +131,88 @@ read_block_bitmap(struct super_block *sb
error_out:
return bh;
}
+
+
+/*
+ * Count number of free blocks in a block group that don't lie in the
+ * metacluster region of the block group.
+ */
+static void
+ext3_init_grp_free_nonmc_blocks(struct super_block *sb,
+ struct buffer_head *bitmap_bh,
+ unsigned long block_group)
+{
+ struct ext3_sb_info *sbi = EXT3_SB(sb);
+ struct ext3_bg_info *bgi = &sbi->s_bginfo[block_group];
+
+ BUG_ON(!test_opt(sb, METACLUSTER));
+
+ spin_lock(sb_bgl_lock(sbi, block_group));
+ if (bgi->bgi_free_nonmc_blocks_count >= 0)
+ goto out;
+
+ bgi->bgi_free_nonmc_blocks_count =
+ ext3_count_free(bitmap_bh, sbi->s_nonmc_blocks_per_group/8);
+
+out:
+ spin_unlock(sb_bgl_lock(sbi, block_group));
+ BUG_ON(bgi->bgi_free_nonmc_blocks_count >
+ sbi->s_nonmc_blocks_per_group);
+}
+
+/*
+ * ext3_update_nonmc_block_count:
+ * Update bgi_free_nonmc_blocks_count for block group 'group_no' following
+ * an allocation or deallocation.
+ *
+ * @group_no: affected block group
+ * @start: start of the [de]allocated range
+ * @count: number of blocks [de]allocated
+ * @allocation: 1 if blocks were allocated, 0 otherwise.
+ */
+static inline void
+ext3_update_nonmc_block_count(struct ext3_sb_info *sbi, unsigned long group_no,
+ ext3_grpblk_t start, unsigned long count,
+ int allocation)
+{
+ struct ext3_bg_info *bginfo = &sbi->s_bginfo[group_no];
+ ext3_grpblk_t change;
+
+ BUG_ON(bginfo->bgi_free_nonmc_blocks_count < 0);
+ BUG_ON(start >= sbi->s_nonmc_blocks_per_group);
+
+ change = min_t(ext3_grpblk_t, start + count,
+ sbi->s_nonmc_blocks_per_group) - start;
+
+ spin_lock(sb_bgl_lock(sbi, group_no));
+ BUG_ON(bginfo->bgi_free_nonmc_blocks_count >
+ sbi->s_nonmc_blocks_per_group);
+ BUG_ON(allocation && bginfo->bgi_free_nonmc_blocks_count < change);
+
+ bginfo->bgi_free_nonmc_blocks_count += (allocation ? -change : change);
+
+ BUG_ON(bginfo->bgi_free_nonmc_blocks_count >
+ sbi->s_nonmc_blocks_per_group);
+ spin_unlock(sb_bgl_lock(sbi, group_no));
+}
+
+/*
+ * allow_mc_alloc:
+ * Check if we can use metacluster region of a block group for general
+ * allocation if needed. Ideally, we should allow this only if
+ * bgi_free_nonmc_blocks_count == 0, but sometimes there is a small number
+ * of blocks which don't get allocated in the first pass, no point
+ * breaking our file at the metacluster boundary because of that, so we
+ * relax the limit to 8.
+ */
+static inline int allow_mc_alloc(struct ext3_sb_info *sbi,
+ struct ext3_bg_info *bgi,
+ ext3_grpblk_t blk)
+{
+ return !(blk >= 0 && blk >= sbi->s_nonmc_blocks_per_group &&
+ bgi->bgi_free_nonmc_blocks_count >= 8);
+}
+
/*
* The reservation window structure operations
* --------------------------------------------
@@ -424,6 +529,7 @@ void ext3_free_blocks_sb(handle_t *handl
struct ext3_group_desc * desc;
struct ext3_super_block * es;
struct ext3_sb_info *sbi;
+ struct ext3_bg_info *bgi;
int err = 0, ret;
ext3_grpblk_t group_freed;
@@ -463,6 +569,13 @@ do_more:
if (!desc)
goto error_return;
+ if (test_opt(sb, METACLUSTER)) {
+ bgi = &sbi->s_bginfo[block_group];
+ if (bgi->bgi_free_nonmc_blocks_count < 0)
+ ext3_init_grp_free_nonmc_blocks(sb, bitmap_bh,
+ block_group);
+ }
+
if (in_range (le32_to_cpu(desc->bg_block_bitmap), block, count) ||
in_range (le32_to_cpu(desc->bg_inode_bitmap), block, count) ||
in_range (block, le32_to_cpu(desc->bg_inode_table),
@@ -582,6 +695,9 @@ do_more:
if (!err) err = ret;
*pdquot_freed_blocks += group_freed;
+ if (test_opt(sb, METACLUSTER) && bit < sbi->s_nonmc_blocks_per_group)
+ ext3_update_nonmc_block_count(sbi, block_group, bit, count, 0);
+
if (overflow && !err) {
block += count;
count = overflow;
@@ -687,6 +803,50 @@ bitmap_search_next_usable_block(ext3_grp
return -1;
}
+static ext3_grpblk_t
+bitmap_find_prev_zero_bit(char *map, ext3_grpblk_t start, ext3_grpblk_t lowest)
+{
+ ext3_grpblk_t k, blk;
+
+ k = start & ~7;
+ while (lowest <= k) {
+ if (map[k/8] != '\255' &&
+ (blk = ext3_find_next_zero_bit(map, k + 8, k))
+ < (k + 8))
+ return blk;
+
+ k -= 8;
+ }
+ return -1;
+}
+
+static ext3_grpblk_t
+bitmap_search_prev_usable_block(ext3_grpblk_t start, struct buffer_head *bh,
+ ext3_grpblk_t lowest)
+{
+ ext3_grpblk_t next;
+ struct journal_head *jh = bh2jh(bh);
+
+ /*
+ * The bitmap search --- search backward alternately through the actual
+ * bitmap and the last-committed copy until we find a bit free in
+ * both
+ */
+ while (start >= lowest) {
+ next = bitmap_find_prev_zero_bit(bh->b_data, start, lowest);
+ if (next < lowest)
+ return -1;
+ if (ext3_test_allocatable(next, bh))
+ return next;
+ jbd_lock_bh_state(bh);
+ if (jh->b_committed_data)
+ start = bitmap_find_prev_zero_bit(jh->b_committed_data,
+ next, lowest);
+ jbd_unlock_bh_state(bh);
+ }
+ return -1;
+}
+
/**
* find_next_usable_block()
* @start: the starting block (group relative) to find next
@@ -794,19 +954,27 @@ claim_block(spinlock_t *lock, ext3_grpbl
* file's own reservation window;
* Otherwise, the allocation range starts from the give goal block, ends at
* the block group's last block.
- *
- * If we failed to allocate the desired block then we may end up crossing to a
- * new bitmap. In that case we must release write access to the old one via
- * ext3_journal_release_buffer(), else we'll run out of credits.
*/
static ext3_grpblk_t
ext3_try_to_allocate(struct super_block *sb, handle_t *handle, int group,
struct buffer_head *bitmap_bh, ext3_grpblk_t grp_goal,
unsigned long *count, struct ext3_reserve_window *my_rsv)
{
+ struct ext3_sb_info *sbi = EXT3_SB(sb);
+ struct ext3_group_desc *gdp;
+ struct ext3_bg_info *bgi = NULL;
+ struct buffer_head *gdp_bh;
ext3_fsblk_t group_first_block;
ext3_grpblk_t start, end;
unsigned long num = 0;
+ const int metaclustering = test_opt(sb, METACLUSTER);
+
+ if (metaclustering)
+ bgi = &sbi->s_bginfo[group];
+
+ gdp = ext3_get_group_desc(sb, group, &gdp_bh);
+ if (!gdp)
+ goto fail_access;
/* we do allocation within the reservation window if we have a window */
if (my_rsv) {
@@ -851,8 +1019,10 @@ repeat:
}
start = grp_goal;
- if (!claim_block(sb_bgl_lock(EXT3_SB(sb), group),
- grp_goal, bitmap_bh)) {
+ if (metaclustering && !allow_mc_alloc(sbi, bgi, grp_goal))
+ goto fail_access;
+
+ if (!claim_block(sb_bgl_lock(sbi, group), grp_goal, bitmap_bh)) {
/*
* The block was allocated by another thread, or it was
* allocated and then freed by another thread
@@ -867,8 +1037,8 @@ repeat:
grp_goal++;
while (num < *count && grp_goal < end
&& ext3_test_allocatable(grp_goal, bitmap_bh)
- && claim_block(sb_bgl_lock(EXT3_SB(sb), group),
- grp_goal, bitmap_bh)) {
+ && (!metaclustering || allow_mc_alloc(sbi, bgi, grp_goal))
+ && claim_block(sb_bgl_lock(sbi, group), grp_goal, bitmap_bh)) {
num++;
grp_goal++;
}
@@ -1099,7 +1269,9 @@ static int alloc_new_reservation(struct
/*
* find_next_reservable_window() simply finds a reservable window
- * inside the given range(start_block, group_end_block).
+ * inside the given range(start_block, group_end_block). The
+ * reservation window must have a reservable free bit inside it for our
+ * callers to work correctly.
*
* To make sure the reservation window has a free bit inside it, we
* need to check the bitmap after we found a reservable window.
@@ -1131,10 +1303,17 @@ retry:
my_rsv->rsv_start - group_first_block,
bitmap_bh, group_end_block - group_first_block + 1);
- if (first_free_block < 0) {
+ if (first_free_block < 0 ||
+ (test_opt(sb, METACLUSTER)
+ && !allow_mc_alloc(EXT3_SB(sb), &EXT3_SB(sb)->s_bginfo[group],
+ first_free_block))) {
/*
- * no free block left on the bitmap, no point
- * to reserve the space. return failed.
+ * No free block left on the bitmap, no point to reserve space,
+ * return failed. We also fail here if metaclustering is enabled
+ * and the first free block in the window lies in the
+ * metacluster while there are free non-mc blocks in the block
+ * group, such a window or any window following it is not useful
+ * to us.
*/
spin_lock(rsv_lock);
if (!rsv_is_empty(&my_rsv->rsv_window))
@@ -1237,25 +1416,17 @@ ext3_try_to_allocate_with_rsv(struct sup
unsigned int group, struct buffer_head *bitmap_bh,
ext3_grpblk_t grp_goal,
struct ext3_reserve_window_node * my_rsv,
- unsigned long *count, int *errp)
+ unsigned long *count)
{
+ struct ext3_bg_info *bgi;
ext3_fsblk_t group_first_block, group_last_block;
ext3_grpblk_t ret = 0;
- int fatal;
unsigned long num = *count;
- *errp = 0;
-
- /*
- * Make sure we use undo access for the bitmap, because it is critical
- * that we do the frozen_data COW on bitmap buffers in all cases even
- * if the buffer is in BJ_Forget state in the committing transaction.
- */
- BUFFER_TRACE(bitmap_bh, "get undo access for new block");
- fatal = ext3_journal_get_undo_access(handle, bitmap_bh);
- if (fatal) {
- *errp = fatal;
- return -1;
+ if (test_opt(sb, METACLUSTER)) {
+ bgi = &EXT3_SB(sb)->s_bginfo[group];
+ if (bgi->bgi_free_nonmc_blocks_count < 0)
+ ext3_init_grp_free_nonmc_blocks(sb, bitmap_bh, group);
}
/*
@@ -1331,19 +1502,6 @@ ext3_try_to_allocate_with_rsv(struct sup
num = *count;
}
out:
- if (ret >= 0) {
- BUFFER_TRACE(bitmap_bh, "journal_dirty_metadata for "
- "bitmap block");
- fatal = ext3_journal_dirty_metadata(handle, bitmap_bh);
- if (fatal) {
- *errp = fatal;
- return -1;
- }
- return ret;
- }
-
- BUFFER_TRACE(bitmap_bh, "journal_release_buffer");
- ext3_journal_release_buffer(handle, bitmap_bh);
return ret;
}
@@ -1389,22 +1547,149 @@ int ext3_should_retry_alloc(struct super
return journal_force_commit_nested(EXT3_SB(sb)->s_journal);
}
+/*
+ * ext3_alloc_indirect_blocks:
+ * Helper function for ext3_new_blocks. Allocates indirect blocks from the
+ * metacluster region only and stores their numbers in new_blocks[].
+ */
+int ext3_alloc_indirect_blocks(struct super_block *sb,
+ struct buffer_head *bitmap_bh,
+ struct ext3_group_desc *gdp,
+ int group_no, unsigned long indirect_blks,
+ ext3_fsblk_t new_blocks[])
+{
+ struct ext3_bg_info *bgi = &EXT3_SB(sb)->s_bginfo[group_no];
+ ext3_grpblk_t blk = EXT3_BLOCKS_PER_GROUP(sb) - 1;
+ ext3_grpblk_t mc_start = EXT3_SB(sb)->s_nonmc_blocks_per_group;
+ ext3_fsblk_t group_first_block;
+ int allocated = 0;
+
+ BUG_ON(!test_opt(sb, METACLUSTER));
+
+ /* This check is racy but that wouldn't harm us. */
+ if (bgi->bgi_free_nonmc_blocks_count >=
+ le16_to_cpu(gdp->bg_free_blocks_count))
+ return 0;
+
+ group_first_block = ext3_group_first_block_no(sb, group_no);
+ while (allocated < indirect_blks && blk >= mc_start) {
+ if (!ext3_test_allocatable(blk, bitmap_bh)) {
+ blk = bitmap_search_prev_usable_block(blk, bitmap_bh,
+ mc_start);
+ continue;
+ }
+ if (claim_block(sb_bgl_lock(EXT3_SB(sb), group_no), blk,
+ bitmap_bh)) {
+ new_blocks[allocated++] = group_first_block + blk;
+ } else {
+ /*
+ * The block was allocated by another thread, or it
+ * was allocated and then freed by another thread
+ */
+ cpu_relax();
+ }
+ if (allocated < indirect_blks)
+ blk = bitmap_search_prev_usable_block(blk, bitmap_bh,
+ mc_start);
+ }
+ return allocated;
+}
+
+/*
+ * check_allocated_blocks:
+ * Helper function for ext3_new_blocks. Checks newly allocated block
+ * numbers.
+ */
+int check_allocated_blocks(ext3_fsblk_t blk, unsigned long num,
+ struct super_block *sb, int group_no,
+ struct ext3_group_desc *gdp,
+ struct buffer_head *bitmap_bh)
+{
+ struct ext3_super_block *es = EXT3_SB(sb)->s_es;
+ struct ext3_sb_info *sbi = EXT3_SB(sb);
+ ext3_fsblk_t grp_blk = blk - ext3_group_first_block_no(sb, group_no);
+
+ if (in_range(le32_to_cpu(gdp->bg_block_bitmap), blk, num) ||
+ in_range(le32_to_cpu(gdp->bg_inode_bitmap), blk, num) ||
+ in_range(blk, le32_to_cpu(gdp->bg_inode_table),
+ EXT3_SB(sb)->s_itb_per_group) ||
+ in_range(blk + num - 1, le32_to_cpu(gdp->bg_inode_table),
+ EXT3_SB(sb)->s_itb_per_group))
+ ext3_error(sb, "ext3_new_blocks",
+ "Allocating block in system zone - "
+ "blocks from "E3FSBLK", length %lu",
+ blk, num);
+
+#ifdef CONFIG_JBD_DEBUG
+ {
+ struct buffer_head *debug_bh;
+
+ /* Record bitmap buffer state in the newly allocated block */
+ debug_bh = sb_find_get_block(sb, blk);
+ if (debug_bh) {
+ BUFFER_TRACE(debug_bh, "state when allocated");
+ BUFFER_TRACE2(debug_bh, bitmap_bh, "bitmap state");
+ brelse(debug_bh);
+ }
+ }
+ jbd_lock_bh_state(bitmap_bh);
+ spin_lock(sb_bgl_lock(sbi, group_no));
+ if (buffer_jbd(bitmap_bh) && bh2jh(bitmap_bh)->b_committed_data) {
+ int i;
+
+ for (i = 0; i < num; i++) {
+ if (ext3_test_bit(grp_blk+i,
+ bh2jh(bitmap_bh)->b_committed_data))
+ printk(KERN_ERR "%s: block was unexpectedly set"
+ " in b_committed_data\n", __FUNCTION__);
+ }
+ }
+ ext3_debug("found bit %d\n", grp_blk);
+ spin_unlock(sb_bgl_lock(sbi, group_no));
+ jbd_unlock_bh_state(bitmap_bh);
+#endif
+
+ if (blk + num - 1 >= le32_to_cpu(es->s_blocks_count)) {
+ ext3_error(sb, "ext3_new_blocks",
+ "block("E3FSBLK") >= blocks count(%d) - "
+ "block_group = %d, es == %p ", blk,
+ le32_to_cpu(es->s_blocks_count), group_no, es);
+ return 1;
+ }
+
+ return 0;
+}
+
/**
- * ext3_new_blocks() -- core block(s) allocation function
- * @handle: handle to this transaction
- * @inode: file inode
- * @goal: given target block(filesystem wide)
- * @count: target number of blocks to allocate
- * @errp: error code
+ * ext3_new_blocks - allocate indirect blocks and direct blocks.
+ * @handle: handle to this transaction
+ * @inode: file inode
+ * @goal: given target block(filesystem wide)
+ * @indirect_blks number of indirect blocks to allocate
+ * @blks number of direct blocks to allocate
+ * @new_blocks this will store the block numbers of indirect blocks
+ * and direct blocks upon return.
*
- * ext3_new_blocks uses a goal block to assist allocation. It tries to
- * allocate block(s) from the block group contains the goal block first. If that
- * fails, it will try to allocate block(s) from other block groups without
- * any specific goal block.
+ * returns the number of direct blocks allocated. Fewer than requested
+ * number of direct blocks may be allocated but all requested indirect
+ * blocks must be allocated in order to return success.
*
+ * Without metaclustering, ext3_new_block allocates all blocks using a
+ * goal block to assist allocation. It tries to allocate block(s) from
+ * the block group contains the goal block first. If that fails, it will
+ * try to allocate block(s) from other block groups without any specific
+ * goal block.
+ *
+ * With metaclustering, the only difference is that indirect block
+ * allocation is first attempted in the metacluster region of the same
+ * block group failing which they are allocated along with direct blocks.
+ *
+ * This function also updates quota and i_blocks field.
*/
-ext3_fsblk_t ext3_new_blocks(handle_t *handle, struct inode *inode,
- ext3_fsblk_t goal, unsigned long *count, int *errp)
+int ext3_new_blocks(handle_t *handle, struct inode *inode,
+ ext3_fsblk_t goal, int indirect_blks, int blks,
+ ext3_fsblk_t new_blocks[4], int *errp)
+
{
struct buffer_head *bitmap_bh = NULL;
struct buffer_head *gdp_bh;
@@ -1413,10 +1698,16 @@ ext3_fsblk_t ext3_new_blocks(handle_t *h
ext3_grpblk_t grp_target_blk; /* blockgroup relative goal block */
ext3_grpblk_t grp_alloc_blk; /* blockgroup-relative allocated block*/
ext3_fsblk_t ret_block; /* filesyetem-wide allocated block */
+ ext3_fsblk_t group_first_block; /* first block in the group */
int bgi; /* blockgroup iteration index */
int fatal = 0, err;
int performed_allocation = 0;
ext3_grpblk_t free_blocks; /* number of free blocks in a group */
+ unsigned long ngroups;
+ unsigned long grp_mc_alloc;/* blocks allocated from mc in a group */
+ unsigned long grp_alloc; /* blocks allocated outside mc in a group */
+ int indirect_blks_done = 0;/* total ind blocks allocated so far */
+ int blks_done = 0; /* total direct blocks allocated */
struct super_block *sb;
struct ext3_group_desc *gdp;
struct ext3_super_block *es;
@@ -1424,23 +1715,23 @@ ext3_fsblk_t ext3_new_blocks(handle_t *h
struct ext3_reserve_window_node *my_rsv = NULL;
struct ext3_block_alloc_info *block_i;
unsigned short windowsz = 0;
+ int i;
#ifdef EXT3FS_DEBUG
static int goal_hits, goal_attempts;
#endif
- unsigned long ngroups;
- unsigned long num = *count;
*errp = -ENOSPC;
sb = inode->i_sb;
if (!sb) {
- printk("ext3_new_block: nonexistent device");
+ printk(KERN_INFO "ext3_new_blocks: nonexistent device");
+ *errp = -ENODEV;
return 0;
}
/*
* Check quota for allocation of this block.
*/
- if (DQUOT_ALLOC_BLOCK(inode, num)) {
+ if (DQUOT_ALLOC_BLOCK(inode, indirect_blks + blks)) {
*errp = -EDQUOT;
return 0;
}
@@ -1474,73 +1765,194 @@ ext3_fsblk_t ext3_new_blocks(handle_t *h
group_no = (goal - le32_to_cpu(es->s_first_data_block)) /
EXT3_BLOCKS_PER_GROUP(sb);
goal_group = group_no;
-retry_alloc:
- gdp = ext3_get_group_desc(sb, group_no, &gdp_bh);
- if (!gdp)
- goto io_error;
-
- free_blocks = le16_to_cpu(gdp->bg_free_blocks_count);
- /*
- * if there is not enough free blocks to make a new resevation
- * turn off reservation for this allocation
- */
- if (my_rsv && (free_blocks < windowsz)
- && (rsv_is_empty(&my_rsv->rsv_window)))
- my_rsv = NULL;
-
- if (free_blocks > 0) {
- grp_target_blk = ((goal - le32_to_cpu(es->s_first_data_block)) %
- EXT3_BLOCKS_PER_GROUP(sb));
- bitmap_bh = read_block_bitmap(sb, group_no);
- if (!bitmap_bh)
- goto io_error;
- grp_alloc_blk = ext3_try_to_allocate_with_rsv(sb, handle,
- group_no, bitmap_bh, grp_target_blk,
- my_rsv, &num, &fatal);
- if (fatal)
- goto out;
- if (grp_alloc_blk >= 0)
- goto allocated;
- }
+retry_alloc:
+ grp_target_blk = ((goal - le32_to_cpu(es->s_first_data_block)) %
+ EXT3_BLOCKS_PER_GROUP(sb));
ngroups = EXT3_SB(sb)->s_groups_count;
smp_rmb();
/*
- * Now search the rest of the groups. We assume that
- * i and gdp correctly point to the last group visited.
+ * Iterate over successive block groups for allocating (any) indirect
+ * blocks and direct blocks until at least one direct block has been
+ * allocated. If metaclustering is enabled, we try allocating indirect
+ * blocks first in the metacluster region and then in the general
+ * region and if that fails too, we repeat the same algorithm in the
+ * next block group and so on. This not only keeps the indirect blocks
+ * together in the metacluster, but also keeps them in close proximity
+ * to their corresponding direct blocks.
+ *
+ * The search begins and ends at the goal group, though the second time
+ * we are at the goal group we try allocating without a goal.
*/
- for (bgi = 0; bgi < ngroups; bgi++) {
- group_no++;
+ bgi = 0;
+ while (bgi < ngroups + 1) {
+ grp_mc_alloc = 0;
+
if (group_no >= ngroups)
group_no = 0;
+
gdp = ext3_get_group_desc(sb, group_no, &gdp_bh);
if (!gdp)
goto io_error;
+
free_blocks = le16_to_cpu(gdp->bg_free_blocks_count);
- /*
- * skip this group if the number of
- * free blocks is less than half of the reservation
- * window size.
- */
- if (free_blocks <= (windowsz/2))
- continue;
+ if (group_no == goal_group) {
+ if (my_rsv && (free_blocks < windowsz)
+ && (rsv_is_empty(&my_rsv->rsv_window)))
+ my_rsv = NULL;
+ if (free_blocks == 0)
+ goto next;
+ } else if (free_blocks <= windowsz/2)
+ goto next;
- brelse(bitmap_bh);
bitmap_bh = read_block_bitmap(sb, group_no);
if (!bitmap_bh)
goto io_error;
+
/*
- * try to allocate block(s) from this group, without a goal(-1).
+ * Make sure we use undo access for the bitmap, because it is
+ * critical that we do the frozen_data COW on bitmap buffers in
+ * all cases even if the buffer is in BJ_Forget state in the
+ * committing transaction.
+ */
+ BUFFER_TRACE(bitmap_bh, "get undo access for new block");
+ fatal = ext3_journal_get_undo_access(handle, bitmap_bh);
+ if (fatal)
+ goto out;
+
+ /*
+ * If metaclustering is enabled, first try to allocate indirect
+ * blocks in the metacluster.
*/
+ if (test_opt(sb, METACLUSTER) &&
+ indirect_blks_done < indirect_blks)
+ grp_mc_alloc = ext3_alloc_indirect_blocks(sb,
+ bitmap_bh, gdp, group_no,
+ indirect_blks - indirect_blks_done,
+ new_blocks + indirect_blks_done);
+
+ /* Allocate data blocks and any leftover indirect blocks. */
+ grp_alloc = indirect_blks + blks
+ - (indirect_blks_done + grp_mc_alloc);
grp_alloc_blk = ext3_try_to_allocate_with_rsv(sb, handle,
- group_no, bitmap_bh, -1, my_rsv,
- &num, &fatal);
+ group_no, bitmap_bh, grp_target_blk,
+ my_rsv, &grp_alloc);
+ if (grp_alloc_blk < 0)
+ grp_alloc = 0;
+
+ /*
+ * If we couldn't allocate anything, there is nothing more to
+ * do with this block group, so move over to the next. But
+ * before that We must release write access to the old one via
+ * ext3_journal_release_buffer(), else we'll run out of credits.
+ */
+ if (grp_mc_alloc == 0 && grp_alloc == 0) {
+ BUFFER_TRACE(bitmap_bh, "journal_release_buffer");
+ ext3_journal_release_buffer(handle, bitmap_bh);
+ goto next;
+ }
+
+ BUFFER_TRACE(bitmap_bh, "journal_dirty_metadata for "
+ "bitmap block");
+ fatal = ext3_journal_dirty_metadata(handle, bitmap_bh);
if (fatal)
goto out;
- if (grp_alloc_blk >= 0)
+
+ ext3_debug("using block group %d(%d)\n",
+ group_no, gdp->bg_free_blocks_count);
+
+ BUFFER_TRACE(gdp_bh, "get_write_access");
+ fatal = ext3_journal_get_write_access(handle, gdp_bh);
+ if (fatal)
+ goto out;
+
+ /* Should this be called before ext3_journal_dirty_metadata? */
+ for (i = 0; i < grp_mc_alloc; i++) {
+ if (check_allocated_blocks(
+ new_blocks[indirect_blks_done + i], 1, sb,
+ group_no, gdp, bitmap_bh))
+ goto out;
+ }
+ if (grp_alloc > 0) {
+ ret_block = ext3_group_first_block_no(sb, group_no) +
+ grp_alloc_blk;
+ if (check_allocated_blocks(ret_block, grp_alloc, sb,
+ group_no, gdp, bitmap_bh))
+ goto out;
+ }
+
+ indirect_blks_done += grp_mc_alloc;
+ performed_allocation = 1;
+
+ /* The caller will add the new buffer to the journal. */
+ if (grp_alloc > 0)
+ ext3_debug("allocating block %lu. "
+ "Goal hits %d of %d.\n",
+ ret_block, goal_hits, goal_attempts);
+
+ spin_lock(sb_bgl_lock(sbi, group_no));
+ gdp->bg_free_blocks_count =
+ cpu_to_le16(le16_to_cpu(gdp->bg_free_blocks_count) -
+ (grp_mc_alloc + grp_alloc));
+ spin_unlock(sb_bgl_lock(sbi, group_no));
+ percpu_counter_mod(&sbi->s_freeblocks_counter,
+ -(grp_mc_alloc + grp_alloc));
+
+ BUFFER_TRACE(gdp_bh, "journal_dirty_metadata for "
+ "group descriptor");
+ err = ext3_journal_dirty_metadata(handle, gdp_bh);
+ if (!fatal)
+ fatal = err;
+
+ sb->s_dirt = 1;
+ if (fatal)
+ goto out;
+
+ brelse(bitmap_bh);
+ bitmap_bh = NULL;
+
+ if (grp_alloc == 0)
+ goto next;
+
+ /* Update block group non-mc block count since we used some. */
+ if (test_opt(sb, METACLUSTER) &&
+ grp_alloc_blk < sbi->s_nonmc_blocks_per_group)
+ ext3_update_nonmc_block_count(sbi, group_no,
+ grp_alloc_blk, grp_alloc, 1);
+
+ /*
+ * Assign all the non-mc blocks that we allocated from this
+ * block group.
+ */
+ group_first_block = ext3_group_first_block_no(sb, group_no);
+ while (grp_alloc > 0 && indirect_blks_done < indirect_blks) {
+ new_blocks[indirect_blks_done++] =
+ group_first_block + grp_alloc_blk;
+ grp_alloc_blk++;
+ grp_alloc--;
+ }
+
+ if (grp_alloc > 0) {
+ blks_done = grp_alloc;
+ new_blocks[indirect_blks_done] =
+ group_first_block + grp_alloc_blk;
goto allocated;
+ }
+
+ /*
+ * If we allocated something but not the minimum required,
+ * it's OK to retry in this group as it might have more free
+ * blocks.
+ */
+ continue;
+
+next:
+ bgi++;
+ group_no++;
+ grp_target_blk = -1;
}
+
/*
* We may end up a bogus ealier ENOSPC error due to
* filesystem is "full" of reservations, but
@@ -1559,96 +1971,11 @@ retry_alloc:
goto out;
allocated:
-
- ext3_debug("using block group %d(%d)\n",
- group_no, gdp->bg_free_blocks_count);
-
- BUFFER_TRACE(gdp_bh, "get_write_access");
- fatal = ext3_journal_get_write_access(handle, gdp_bh);
- if (fatal)
- goto out;
-
- ret_block = grp_alloc_blk + ext3_group_first_block_no(sb, group_no);
-
- if (in_range(le32_to_cpu(gdp->bg_block_bitmap), ret_block, num) ||
- in_range(le32_to_cpu(gdp->bg_inode_bitmap), ret_block, num) ||
- in_range(ret_block, le32_to_cpu(gdp->bg_inode_table),
- EXT3_SB(sb)->s_itb_per_group) ||
- in_range(ret_block + num - 1, le32_to_cpu(gdp->bg_inode_table),
- EXT3_SB(sb)->s_itb_per_group))
- ext3_error(sb, "ext3_new_block",
- "Allocating block in system zone - "
- "blocks from "E3FSBLK", length %lu",
- ret_block, num);
-
- performed_allocation = 1;
-
-#ifdef CONFIG_JBD_DEBUG
- {
- struct buffer_head *debug_bh;
-
- /* Record bitmap buffer state in the newly allocated block */
- debug_bh = sb_find_get_block(sb, ret_block);
- if (debug_bh) {
- BUFFER_TRACE(debug_bh, "state when allocated");
- BUFFER_TRACE2(debug_bh, bitmap_bh, "bitmap state");
- brelse(debug_bh);
- }
- }
- jbd_lock_bh_state(bitmap_bh);
- spin_lock(sb_bgl_lock(sbi, group_no));
- if (buffer_jbd(bitmap_bh) && bh2jh(bitmap_bh)->b_committed_data) {
- int i;
-
- for (i = 0; i < num; i++) {
- if (ext3_test_bit(grp_alloc_blk+i,
- bh2jh(bitmap_bh)->b_committed_data)) {
- printk("%s: block was unexpectedly set in "
- "b_committed_data\n", __FUNCTION__);
- }
- }
- }
- ext3_debug("found bit %d\n", grp_alloc_blk);
- spin_unlock(sb_bgl_lock(sbi, group_no));
- jbd_unlock_bh_state(bitmap_bh);
-#endif
-
- if (ret_block + num - 1 >= le32_to_cpu(es->s_blocks_count)) {
- ext3_error(sb, "ext3_new_block",
- "block("E3FSBLK") >= blocks count(%d) - "
- "block_group = %d, es == %p ", ret_block,
- le32_to_cpu(es->s_blocks_count), group_no, es);
- goto out;
- }
-
- /*
- * It is up to the caller to add the new buffer to a journal
- * list of some description. We don't know in advance whether
- * the caller wants to use it as metadata or data.
- */
- ext3_debug("allocating block %lu. Goal hits %d of %d.\n",
- ret_block, goal_hits, goal_attempts);
-
- spin_lock(sb_bgl_lock(sbi, group_no));
- gdp->bg_free_blocks_count =
- cpu_to_le16(le16_to_cpu(gdp->bg_free_blocks_count)-num);
- spin_unlock(sb_bgl_lock(sbi, group_no));
- percpu_counter_mod(&sbi->s_freeblocks_counter, -num);
-
- BUFFER_TRACE(gdp_bh, "journal_dirty_metadata for group descriptor");
- err = ext3_journal_dirty_metadata(handle, gdp_bh);
- if (!fatal)
- fatal = err;
-
- sb->s_dirt = 1;
- if (fatal)
- goto out;
-
*errp = 0;
- brelse(bitmap_bh);
- DQUOT_FREE_BLOCK(inode, *count-num);
- *count = num;
- return ret_block;
+ DQUOT_FREE_BLOCK(inode,
+ indirect_blks + blks - indirect_blks_done - blks_done);
+
+ return blks_done;
io_error:
*errp = -EIO;
@@ -1661,7 +1988,13 @@ out:
* Undo the block allocation
*/
if (!performed_allocation)
- DQUOT_FREE_BLOCK(inode, *count);
+ DQUOT_FREE_BLOCK(inode, indirect_blks + blks);
+ /*
+ * Free any indirect blocks we allocated already. If the transaction
+ * has been aborted this is essentially a no-op.
+ */
+ for (i = 0; i < indirect_blks_done; i++)
+ ext3_free_blocks(handle, inode, new_blocks[i], 1);
brelse(bitmap_bh);
return 0;
}
@@ -1669,9 +2002,13 @@ out:
ext3_fsblk_t ext3_new_block(handle_t *handle, struct inode *inode,
ext3_fsblk_t goal, int *errp)
{
- unsigned long count = 1;
+ ext3_fsblk_t new_blocks[4];
- return ext3_new_blocks(handle, inode, goal, &count, errp);
+ ext3_new_blocks(handle, inode, goal, 0, 1, new_blocks, errp);
+ if (*errp)
+ return 0;
+
+ return new_blocks[0];
}
/**
diff -rupdN linux-2.6.23.13-clean/fs/ext3/bitmap.c linux-2.6.23.13-ext3mc/fs/ext3/bitmap.c
--- linux-2.6.23.13-clean/fs/ext3/bitmap.c 2008-01-09 12:18:17.000000000 -0500
+++ linux-2.6.23.13-ext3mc/fs/ext3/bitmap.c 2008-01-12 22:30:19.000000000 -0500
@@ -11,8 +11,6 @@
#include <linux/jbd.h>
#include <linux/ext3_fs.h>
-#ifdef EXT3FS_DEBUG
-
static int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
unsigned long ext3_count_free (struct buffer_head * map, unsigned int numchars)
@@ -27,6 +25,3 @@ unsigned long ext3_count_free (struct bu
nibblemap[(map->b_data[i] >> 4) & 0xf];
return (sum);
}
-
-#endif /* EXT3FS_DEBUG */
-
diff -rupdN linux-2.6.23.13-clean/fs/ext3/inode.c linux-2.6.23.13-ext3mc/fs/ext3/inode.c
--- linux-2.6.23.13-clean/fs/ext3/inode.c 2008-01-09 12:18:17.000000000 -0500
+++ linux-2.6.23.13-ext3mc/fs/ext3/inode.c 2008-01-14 14:12:13.000000000 -0500
@@ -36,10 +36,33 @@
#include <linux/mpage.h>
#include <linux/uio.h>
#include <linux/bio.h>
+#include <linux/sort.h>
#include "xattr.h"
#include "acl.h"
+typedef struct {
+ __le32 *p;
+ __le32 key;
+ struct buffer_head *bh;
+} Indirect;
+
+struct ext3_ind_read_info {
+ int count;
+ int seq_prefetch;
+ long size;
+ struct buffer_head *bh[0];
+};
+
+# define EXT3_IND_READ_INFO_SIZE(_c) \
+ (sizeof(struct ext3_ind_read_info) + \
+ sizeof(struct buffer_head *) * (_c))
+
+# define EXT3_IND_READ_MAX (32)
+
static int ext3_writepage_trans_blocks(struct inode *inode);
+static Indirect *ext3_read_indblocks(struct inode *inode, int iblock,
+ int depth, int offsets[4],
+ Indirect chain[4], int *err);
/*
* Test whether an inode is a fast symlink.
@@ -233,12 +256,6 @@ no_delete:
clear_inode(inode); /* We must guarantee clearing of inode... */
}
-typedef struct {
- __le32 *p;
- __le32 key;
- struct buffer_head *bh;
-} Indirect;
-
static inline void add_chain(Indirect *p, struct buffer_head *bh, __le32 *v)
{
p->key = *(p->p = v);
@@ -352,18 +369,21 @@ static int ext3_block_to_path(struct ino
* the whole chain, all way to the data (returns %NULL, *err == 0).
*/
static Indirect *ext3_get_branch(struct inode *inode, int depth, int *offsets,
- Indirect chain[4], int *err)
+ Indirect chain[4], int ind_readahead, int *err)
{
struct super_block *sb = inode->i_sb;
Indirect *p = chain;
struct buffer_head *bh;
+ int index;
*err = 0;
/* i_data is not going away, no lock needed */
add_chain (chain, NULL, EXT3_I(inode)->i_data + *offsets);
if (!p->key)
goto no_block;
- while (--depth) {
+ for (index = 0; index < depth - 1; index++) {
+ if (ind_readahead && depth > 2 && index == depth - 2)
+ break;
bh = sb_bread(sb, le32_to_cpu(p->key));
if (!bh)
goto failure;
@@ -396,7 +416,11 @@ no_block:
* It is used when heuristic for sequential allocation fails.
* Rules are:
* + if there is a block to the left of our position - allocate near it.
- * + if pointer will live in indirect block - allocate near that block.
+ * + If METACLUSTER options is not specified, allocate the data
+ * block close to the metadata block. Otherwise, if pointer will live in
+ * indirect block, we cannot allocate near the indirect block since
+ * indirect blocks are allocated in the metacluster, just put in the same
+ * cylinder group as the inode.
* + if pointer will live in inode - allocate in the same
* cylinder group.
*
@@ -421,9 +445,11 @@ static ext3_fsblk_t ext3_find_near(struc
return le32_to_cpu(*p);
}
- /* No such thing, so let's try location of indirect block */
- if (ind->bh)
- return ind->bh->b_blocknr;
+ if (!test_opt(inode->i_sb, METACLUSTER)) {
+ /* No such thing, so let's try location of indirect block */
+ if (ind->bh)
+ return ind->bh->b_blocknr;
+ }
/*
* It is going to be referred to from the inode itself? OK, just put it
@@ -475,8 +501,7 @@ static ext3_fsblk_t ext3_find_goal(struc
* @blks: number of data blocks to be mapped.
* @blocks_to_boundary: the offset in the indirect block
*
- * return the total number of blocks to be allocate, including the
- * direct and indirect blocks.
+ * return the total number of direct blocks to be allocated.
*/
static int ext3_blks_to_allocate(Indirect *branch, int k, unsigned long blks,
int blocks_to_boundary)
@@ -505,75 +530,18 @@ static int ext3_blks_to_allocate(Indirec
}
/**
- * ext3_alloc_blocks: multiple allocate blocks needed for a branch
- * @indirect_blks: the number of blocks need to allocate for indirect
- * blocks
- *
- * @new_blocks: on return it will store the new block numbers for
- * the indirect blocks(if needed) and the first direct block,
- * @blks: on return it will store the total number of allocated
- * direct blocks
- */
-static int ext3_alloc_blocks(handle_t *handle, struct inode *inode,
- ext3_fsblk_t goal, int indirect_blks, int blks,
- ext3_fsblk_t new_blocks[4], int *err)
-{
- int target, i;
- unsigned long count = 0;
- int index = 0;
- ext3_fsblk_t current_block = 0;
- int ret = 0;
-
- /*
- * Here we try to allocate the requested multiple blocks at once,
- * on a best-effort basis.
- * To build a branch, we should allocate blocks for
- * the indirect blocks(if not allocated yet), and at least
- * the first direct block of this branch. That's the
- * minimum number of blocks need to allocate(required)
- */
- target = blks + indirect_blks;
-
- while (1) {
- count = target;
- /* allocating blocks for indirect blocks and direct blocks */
- current_block = ext3_new_blocks(handle,inode,goal,&count,err);
- if (*err)
- goto failed_out;
-
- target -= count;
- /* allocate blocks for indirect blocks */
- while (index < indirect_blks && count) {
- new_blocks[index++] = current_block++;
- count--;
- }
-
- if (count > 0)
- break;
- }
-
- /* save the new block number for the first direct block */
- new_blocks[index] = current_block;
-
- /* total number of blocks allocated for direct blocks */
- ret = count;
- *err = 0;
- return ret;
-failed_out:
- for (i = 0; i <index; i++)
- ext3_free_blocks(handle, inode, new_blocks[i], 1);
- return ret;
-}
-
-/**
* ext3_alloc_branch - allocate and set up a chain of blocks.
* @inode: owner
* @indirect_blks: number of allocated indirect blocks
* @blks: number of allocated direct blocks
+ * @goal: goal for allocation
* @offsets: offsets (in the blocks) to store the pointers to next.
* @branch: place to store the chain in.
*
- * This function allocates blocks, zeroes out all but the last one,
+ * returns error and number of direct blocks allocated via *blks
+ *
+ * This function allocates indirect_blks + *blks, zeroes out all
+ * indirect blocks,
* links them into chain and (if we are synchronous) writes them to disk.
* In other words, it prepares a branch that can be spliced onto the
* inode. It stores the information about that chain in the branch[], in
@@ -602,7 +570,7 @@ static int ext3_alloc_branch(handle_t *h
ext3_fsblk_t new_blocks[4];
ext3_fsblk_t current_block;
- num = ext3_alloc_blocks(handle, inode, goal, indirect_blks,
+ num = ext3_new_blocks(handle, inode, goal, indirect_blks,
*blks, new_blocks, &err);
if (err)
return err;
@@ -799,17 +767,21 @@ int ext3_get_blocks_handle(handle_t *han
int blocks_to_boundary = 0;
int depth;
struct ext3_inode_info *ei = EXT3_I(inode);
- int count = 0;
+ int count = 0, ind_readahead;
ext3_fsblk_t first_block = 0;
-
J_ASSERT(handle != NULL || create == 0);
depth = ext3_block_to_path(inode,iblock,offsets,&blocks_to_boundary);
if (depth == 0)
goto out;
- partial = ext3_get_branch(inode, depth, offsets, chain, &err);
+ ind_readahead = !create && depth > 2;
+ partial = ext3_get_branch(inode, depth, offsets, chain,
+ ind_readahead, &err);
+ if (!partial && ind_readahead)
+ partial = ext3_read_indblocks(inode, iblock, depth,
+ offsets, chain, &err);
/* Simplest case - block found, no allocation needed */
if (!partial) {
@@ -844,7 +816,7 @@ int ext3_get_blocks_handle(handle_t *han
}
/* Next simple case - plain lookup or failed read of indirect block */
- if (!create || err == -EIO)
+ if (!create || (err && err != -EAGAIN))
goto cleanup;
mutex_lock(&ei->truncate_mutex);
@@ -866,7 +838,8 @@ int ext3_get_blocks_handle(handle_t *han
brelse(partial->bh);
partial--;
}
- partial = ext3_get_branch(inode, depth, offsets, chain, &err);
+ partial = ext3_get_branch(inode, depth, offsets, chain, 0,
+ &err);
if (!partial) {
count++;
mutex_unlock(&ei->truncate_mutex);
@@ -1907,7 +1880,7 @@ static Indirect *ext3_find_shared(struct
/* Make k index the deepest non-null offest + 1 */
for (k = depth; k > 1 && !offsets[k-1]; k--)
;
- partial = ext3_get_branch(inode, k, offsets, chain, &err);
+ partial = ext3_get_branch(inode, k, offsets, chain, 0, &err);
/* Writer: pointers */
if (!partial)
partial = chain + k-1;
@@ -3230,3 +3203,561 @@ int ext3_change_inode_journal_flag(struc
return err;
}
+
+/*
+ * ext3_ind_read_end_bio --
+ *
+ * bio callback for read IO issued from ext3_read_indblocks.
+ * May be called multiple times until the whole I/O completes at
+ * which point bio->bi_size = 0 and it frees read_info and bio.
+ * The first time it is called, first_bh is unlocked so that any sync
+ * waier can unblock.
+ */
+static int ext3_ind_read_end_bio(struct bio *bio, unsigned int bytes_done,
+ int err)
+{
+ struct ext3_ind_read_info *read_info = bio->bi_private;
+ struct buffer_head *bh;
+ int uptodate = !err && test_bit(BIO_UPTODATE, &bio->bi_flags);
+ int i;
+
+ if (err == -EOPNOTSUPP)
+ set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
+
+ /* Wait for all buffers to finish - is this needed? */
+ if (bio->bi_size)
+ return 1;
+
+ for (i = 0; i < read_info->count; i++) {
+ bh = read_info->bh[i];
+ if (err == -EOPNOTSUPP)
+ set_bit(BH_Eopnotsupp, &bh->b_state);
+
+ if (uptodate) {
+ BUG_ON(buffer_uptodate(bh));
+ BUG_ON(ext3_buffer_prefetch(bh));
+ set_buffer_uptodate(bh);
+ if (read_info->seq_prefetch)
+ ext3_set_buffer_prefetch(bh);
+ }
+
+ unlock_buffer(bh);
+ brelse(bh);
+ }
+
+ kfree(read_info);
+ bio_put(bio);
+ return 0;
+}
+
+/*
+ * ext3_get_max_read --
+ * @inode: inode of file.
+ * @block: block number in file (starting from zero).
+ * @offset_in_dind_block: offset of the indirect block inside it's
+ * parent doubly-indirect block.
+ *
+ * Compute the maximum no. of indirect blocks that can be read
+ * satisfying following constraints:
+ * - Don't read indirect blocks beyond the end of current
+ * doubly-indirect block.
+ * - Don't read beyond eof.
+ */
+static inline unsigned long ext3_get_max_read(const struct inode *inode,
+ int block,
+ int offset_in_dind_block)
+{
+ const struct super_block *sb = inode->i_sb;
+ unsigned long max_read;
+ unsigned long ptrs = EXT3_ADDR_PER_BLOCK(inode->i_sb);
+ unsigned long ptrs_bits = EXT3_ADDR_PER_BLOCK_BITS(inode->i_sb);
+ unsigned long blocks_in_file =
+ (inode->i_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits;
+ unsigned long remaining_ind_blks_in_dind =
+ (ptrs >= offset_in_dind_block) ? (ptrs - offset_in_dind_block)
+ : 0;
+ unsigned long remaining_ind_blks_before_eof =
+ ((blocks_in_file - EXT3_NDIR_BLOCKS + ptrs - 1) >> ptrs_bits) -
+ ((block - EXT3_NDIR_BLOCKS) >> ptrs_bits);
+
+ BUG_ON(block >= blocks_in_file);
+
+ max_read = min_t(unsigned long, remaining_ind_blks_in_dind,
+ remaining_ind_blks_before_eof);
+
+ BUG_ON(max_read < 1);
+
+ return max_read;
+}
+
+static void ext3_read_indblocks_submit(struct bio **pbio,
+ struct ext3_ind_read_info **pread_info,
+ int *read_cnt, int seq_prefetch)
+{
+ struct bio *bio = *pbio;
+ struct ext3_ind_read_info *read_info = *pread_info;
+
+ BUG_ON(*read_cnt < 1);
+
+ read_info->seq_prefetch = seq_prefetch;
+ read_info->count = *read_cnt;
+ read_info->size = bio->bi_size;
+ bio->bi_private = read_info;
+ bio->bi_end_io = ext3_ind_read_end_bio;
+ submit_bio(READ, bio);
+
+ *pbio = NULL;
+ *pread_info = NULL;
+ *read_cnt = 0;
+}
+
+struct ind_block_info {
+ ext3_fsblk_t blockno;
+ struct buffer_head *bh;
+};
+
+static int ind_info_cmp(const void *a, const void *b)
+{
+ struct ind_block_info *info_a = (struct ind_block_info *)a;
+ struct ind_block_info *info_b = (struct ind_block_info *)b;
+
+ return info_a->blockno - info_b->blockno;
+}
+
+static void ind_info_swap(void *a, void *b, int size)
+{
+ struct ind_block_info *info_a = (struct ind_block_info *)a;
+ struct ind_block_info *info_b = (struct ind_block_info *)b;
+ struct ind_block_info tmp;
+
+ tmp = *info_a;
+ *info_a = *info_b;
+ *info_b = tmp;
+}
+
+/*
+ * ext3_read_indblocks_async --
+ * @sb: super block
+ * @ind_blocks[]: array of indirect block numbers on disk
+ * @count: maximum number of indirect blocks to read
+ * @first_bh: buffer_head for indirect block ind_blocks[0], may be
+ * NULL
+ * @seq_prefetch: if this is part of a sequential prefetch and buffers'
+ * prefetch bit must be set.
+ * @blocks_done: number of blocks considered for prefetching.
+ *
+ * Issue a single bio request to read upto count buffers identified in
+ * ind_blocks[]. Fewer than count buffers may be read in some cases:
+ * - If a buffer is found to be uptodate and it's prefetch bit is set, we
+ * don't look at any more buffers as they will most likely be in the cache.
+ * - We skip buffers we cannot lock without blocking (except for first_bh
+ * if specified).
+ * - We skip buffers beyond a certain range on disk.
+ *
+ * This function must issue read on first_bh if specified unless of course
+ * it's already uptodate.
+ */
+static int ext3_read_indblocks_async(struct super_block *sb,
+ const __le32 ind_blocks[], int count,
+ struct buffer_head *first_bh,
+ int seq_prefetch,
+ unsigned long *blocks_done)
+{
+ struct buffer_head *bh;
+ struct bio *bio = NULL;
+ struct ext3_ind_read_info *read_info = NULL;
+ int read_cnt = 0, blk;
+ ext3_fsblk_t prev_blk = 0, io_start_blk = 0, curr;
+ struct ind_block_info *ind_info = NULL;
+ int err = 0, ind_info_count = 0;
+
+ BUG_ON(count < 1);
+ /* Don't move this to ext3_get_max_read() since callers often need to
+ * trim the count returned by that function. So this bound must only
+ * be imposed at the last moment. */
+ count = min_t(unsigned long, count, EXT3_IND_READ_MAX);
+ *blocks_done = 0UL;
+
+ if (count == 1 && first_bh) {
+ lock_buffer(first_bh);
+ get_bh(first_bh);
+ first_bh->b_end_io = end_buffer_read_sync;
+ submit_bh(READ, first_bh);
+ *blocks_done = 1UL;
+ return 0;
+ }
+
+ ind_info = kmalloc(count * sizeof(*ind_info), GFP_KERNEL);
+ if (unlikely(!ind_info))
+ return -ENOMEM;
+
+ /*
+ * First pass: sort block numbers for all indirect blocks that we'll
+ * read. This allows us to scan blocks in sequenial order during the
+ * second pass which helps coalasce requests to contiguous blocks.
+ * Since we sort block numbers here instead of assuming any specific
+ * layout on the disk, we have some protection against different
+ * indirect block layout strategies as long as they keep all indirect
+ * blocks close by.
+ */
+ for (blk = 0; blk < count; blk++) {
+ curr = le32_to_cpu(ind_blocks[blk]);
+ if (!curr)
+ continue;
+
+ /*
+ * Skip this block if it lies too far from blocks we have
+ * already decided to read. "Too far" should typically indicate
+ * lying on a different track on the disk. EXT3_IND_READ_MAX
+ * seems reasonable for most disks.
+ */
+ if (io_start_blk > 0 &&
+ (max(io_start_blk, curr) - min(io_start_blk, curr) >=
+ EXT3_IND_READ_MAX))
+ continue;
+
+ if (blk == 0 && first_bh) {
+ bh = first_bh;
+ get_bh(first_bh);
+ } else {
+ bh = sb_getblk(sb, curr);
+ if (unlikely(!bh)) {
+ err = -ENOMEM;
+ goto failure;
+ }
+ }
+
+ if (buffer_uptodate(bh)) {
+ if (ext3_buffer_prefetch(bh)) {
+ brelse(bh);
+ break;
+ }
+ brelse(bh);
+ continue;
+ }
+
+ if (io_start_blk == 0)
+ io_start_blk = curr;
+
+ ind_info[ind_info_count].blockno = curr;
+ ind_info[ind_info_count].bh = bh;
+ ind_info_count++;
+ }
+ *blocks_done = blk;
+
+ sort(ind_info, ind_info_count, sizeof(*ind_info),
+ ind_info_cmp, ind_info_swap);
+
+ /* Second pass: compose bio requests and issue them. */
+ for (blk = 0; blk < ind_info_count; blk++) {
+ bh = ind_info[blk].bh;
+ curr = ind_info[blk].blockno;
+
+ if (prev_blk > 0 && curr != prev_blk + 1) {
+ ext3_read_indblocks_submit(&bio, &read_info,
+ &read_cnt, seq_prefetch);
+ prev_blk = 0;
+ }
+
+ /* Lock the buffer without blocking, skipping any buffers
+ * which would require us to block. first_bh when specified is
+ * an exception as caller typically wants it to be read for
+ * sure (e.g., ext3_read_indblocks_sync).
+ */
+ if (bh == first_bh) {
+ lock_buffer(bh);
+ } else if (test_set_buffer_locked(bh)) {
+ brelse(bh);
+ continue;
+ }
+
+ /* Check again with the buffer locked. */
+ if (buffer_uptodate(bh)) {
+ if (ext3_buffer_prefetch(bh)) {
+ unlock_buffer(bh);
+ brelse(bh);
+ break;
+ }
+ unlock_buffer(bh);
+ brelse(bh);
+ continue;
+ }
+
+ if (read_cnt == 0) {
+ /* read_info freed in ext3_ind_read_end_bio(). */
+ read_info = kmalloc(EXT3_IND_READ_INFO_SIZE(count),
+ GFP_KERNEL);
+ if (unlikely(!read_info)) {
+ err = -ENOMEM;
+ goto failure;
+ }
+
+ bio = bio_alloc(GFP_KERNEL, count);
+ if (unlikely(!bio)) {
+ err = -ENOMEM;
+ goto failure;
+ }
+ bio->bi_sector = bh->b_blocknr * (bh->b_size >> 9);
+ bio->bi_bdev = bh->b_bdev;
+ }
+
+ if (bio_add_page(bio, bh->b_page, bh->b_size, bh_offset(bh))
+ < bh->b_size) {
+ brelse(bh);
+ if (read_cnt == 0)
+ goto failure;
+
+ break;
+ }
+
+ read_info->bh[read_cnt++] = bh;
+ prev_blk = curr;
+ }
+
+ if (read_cnt == 0)
+ goto done;
+
+ ext3_read_indblocks_submit(&bio, &read_info, &read_cnt, seq_prefetch);
+
+ kfree(ind_info);
+ return 0;
+
+failure:
+ while (--read_cnt >= 0) {
+ unlock_buffer(read_info->bh[read_cnt]);
+ brelse(read_info->bh[read_cnt]);
+ }
+ *blocks_done = 0UL;
+
+done:
+ kfree(read_info);
+
+ if (bio)
+ bio_put(bio);
+
+ kfree(ind_info);
+ return err;
+}
+
+/*
+ * ext3_read_indblocks_sync --
+ * @sb: super block
+ * @ind_blocks[]: array of indirect block numbers on disk
+ * @count: maximum number of indirect blocks to read
+ * @first_bh: buffer_head for indirect block ind_blocks[0], must be
+ * non-NULL.
+ * @seq_prefetch: set prefetch bit of buffers, used when this is part of
+ * a sequential prefetch.
+ * @blocks_done: number of blocks considered for prefetching.
+ *
+ * Synchronously read at most count indirect blocks listed in
+ * ind_blocks[]. This function calls ext3_read_indblocks_async() to do all
+ * the hard work. It waits for read to complete on first_bh before
+ * returning.
+ */
+
+static int ext3_read_indblocks_sync(struct super_block *sb,
+ const __le32 ind_blocks[], int count,
+ struct buffer_head *first_bh,
+ int seq_prefetch,
+ unsigned long *blocks_done)
+{
+ int err;
+
+ BUG_ON(count < 1);
+ BUG_ON(!first_bh);
+
+ err = ext3_read_indblocks_async(sb, ind_blocks, count, first_bh,
+ seq_prefetch, blocks_done);
+ if (err)
+ return err;
+
+ wait_on_buffer(first_bh);
+ if (!buffer_uptodate(first_bh))
+ err = -EIO;
+
+ /* if seq_prefetch != 0, ext3_read_indblocks_async() sets prefetch bit
+ * for all buffers, but the first buffer for sync IO is never a prefetch
+ * buffer since it's needed presently so mark it so.
+ */
+ if (seq_prefetch)
+ ext3_clear_buffer_prefetch(first_bh);
+
+ BUG_ON(ext3_buffer_prefetch(first_bh));
+
+ return err;
+}
+
+/*
+ * ext3_read_indblocks --
+ *
+ * @inode: inode of file
+ * @iblock: block number inside file (starting from 0).
+ * @depth: depth of path from inode to data block.
+ * @offsets: array of offsets within blocks identified in 'chain'.
+ * @chain: array of Indirect with info about all levels of blocks until
+ * the data block.
+ * @err: error pointer.
+ *
+ * This function is called after reading all metablocks leading to 'iblock'
+ * except the (singly) indirect block. It reads the indirect block if not
+ * already in the cache and may also prefetch next few indirect blocks.
+ * It uses a combination of synchronous and asynchronous requests to
+ * accomplish this. We do prefetching even for random reads by reading
+ * ahead one indirect block since reads of size >=512KB have at least 12%
+ * chance of spanning two indirect blocks.
+ */
+
+static Indirect *ext3_read_indblocks(struct inode *inode, int iblock,
+ int depth, int offsets[4],
+ Indirect chain[4], int *err)
+{
+ struct super_block *sb = inode->i_sb;
+ struct buffer_head *first_bh, *prev_bh;
+ unsigned long max_read, blocks_done = 0;
+ __le32 *ind_blocks;
+
+ /* Must have doubly indirect block for prefetching indirect blocks. */
+ BUG_ON(depth <= 2);
+ BUG_ON(!chain[depth-2].key);
+
+ *err = 0;
+
+ /* Handle first block */
+ ind_blocks = chain[depth-2].p;
+ first_bh = sb_getblk(sb, le32_to_cpu(ind_blocks[0]));
+ if (unlikely(!first_bh)) {
+ printk(KERN_ERR "Failed to get block %u for sb %p\n",
+ le32_to_cpu(ind_blocks[0]), sb);
+ goto failure;
+ }
+
+ BUG_ON(first_bh->b_size != sb->s_blocksize);
+
+ if (buffer_uptodate(first_bh)) {
+ /* Found the buffer in cache, either it was accessed recently or
+ * it was prefetched while reading previous indirect block(s).
+ * We need to figure out if we need to prefetch the following
+ * indirect blocks.
+ */
+ if (!ext3_buffer_prefetch(first_bh)) {
+ /* Either we've seen this indirect block before while
+ * accessing another data block, or this is a random
+ * read. In the former case, we must have done the
+ * needful the first time we had a cache hit on this
+ * indirect block, in the latter case we obviously
+ * don't need to do any prefetching.
+ */
+ goto done;
+ }
+
+ max_read = ext3_get_max_read(inode, iblock,
+ offsets[depth-2]);
+
+ /* This indirect block is in the cache due to prefetching and
+ * this is its first cache hit, clear the prefetch bit and
+ * make sure the following blocks are also prefetched.
+ */
+ ext3_clear_buffer_prefetch(first_bh);
+
+ if (max_read >= 2) {
+ /* ext3_read_indblocks_async() stops at the first
+ * indirect block which has the prefetch bit set which
+ * will most likely be the very next indirect block.
+ */
+ ext3_read_indblocks_async(sb, &ind_blocks[1],
+ max_read - 1,
+ NULL, 1, &blocks_done);
+ }
+
+ } else {
+ /* Buffer is not in memory, we need to read it. If we are
+ * reading sequentially from the previous indirect block, we
+ * have just detected a sequential read and we must prefetch
+ * some indirect blocks for future.
+ */
+
+ max_read = ext3_get_max_read(inode, iblock,
+ offsets[depth-2]);
+
+ if ((ind_blocks - (__le32 *)chain[depth-2].bh->b_data) >= 1) {
+ prev_bh = sb_getblk(sb, le32_to_cpu(ind_blocks[-1]));
+ if (buffer_uptodate(prev_bh) &&
+ !ext3_buffer_prefetch(prev_bh)) {
+ /* Detected sequential read. */
+ brelse(prev_bh);
+
+ /* Sync read indirect block, also read the next
+ * few indirect blocks.
+ */
+ *err = ext3_read_indblocks_sync(sb, ind_blocks,
+ max_read, first_bh, 1,
+ &blocks_done);
+
+ if (*err)
+ goto out;
+
+ /* In case the very next indirect block is
+ * discontiguous by a non-trivial amount,
+ * ext3_read_indblocks_sync() above won't
+ * prefetch it (indicated by blocks_done < 2).
+ * So to help sequential read, schedule an
+ * async request for reading the next
+ * contiguous indirect block range (which
+ * in metaclustering case would be the next
+ * metacluster, without metaclustering it
+ * would be the next indirect block). This is
+ * expected to benefit the non-metaclustering
+ * case.
+ */
+ if (max_read >= 2 && blocks_done < 2)
+ ext3_read_indblocks_async(sb,
+ &ind_blocks[1],
+ max_read - 1,
+ NULL, 1, &blocks_done);
+
+ goto done;
+ }
+ brelse(prev_bh);
+ }
+
+ /* Either random read, or sequential detection failed above.
+ * We always prefetch the next indirect block in this case
+ * whenever possible.
+ * This is because for random reads of size ~512KB, there is
+ * >12% chance that a read will span two indirect blocks.
+ */
+ *err = ext3_read_indblocks_sync(sb, ind_blocks,
+ (max_read >= 2) ? 2 : 1,
+ first_bh, 0, &blocks_done);
+ if (*err)
+ goto out;
+ }
+
+done:
+ /* Reader: pointers */
+ if (!verify_chain(chain, &chain[depth - 2])) {
+ brelse(first_bh);
+ goto changed;
+ }
+ add_chain(&chain[depth - 1], first_bh,
+ (__le32 *)first_bh->b_data + offsets[depth - 1]);
+ /* Reader: end */
+ if (!chain[depth - 1].key)
+ goto out;
+
+ BUG_ON(!buffer_uptodate(first_bh));
+ return NULL;
+
+changed:
+ *err = -EAGAIN;
+ goto out;
+failure:
+ *err = -EIO;
+out:
+ if (*err) {
+ ext3_debug("Error %d reading indirect blocks\n", *err);
+ return &chain[depth - 2];
+ } else
+ return &chain[depth - 1];
+}
diff -rupdN linux-2.6.23.13-clean/fs/ext3/super.c linux-2.6.23.13-ext3mc/fs/ext3/super.c
--- linux-2.6.23.13-clean/fs/ext3/super.c 2008-01-09 12:18:17.000000000 -0500
+++ linux-2.6.23.13-ext3mc/fs/ext3/super.c 2008-01-12 22:30:19.000000000 -0500
@@ -556,6 +556,9 @@ static int ext3_show_options(struct seq_
else if (test_opt(sb, DATA_FLAGS) == EXT3_MOUNT_WRITEBACK_DATA)
seq_puts(seq, ",data=writeback");
+ if (test_opt(sb, METACLUSTER))
+ seq_puts(seq, ",metacluster");
+
ext3_show_quota_options(seq, sb);
return 0;
@@ -684,7 +687,7 @@ enum {
Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
Opt_ignore, Opt_barrier, Opt_err, Opt_resize, Opt_usrquota,
- Opt_grpquota
+ Opt_grpquota, Opt_metacluster
};
static match_table_t tokens = {
@@ -734,6 +737,7 @@ static match_table_t tokens = {
{Opt_quota, "quota"},
{Opt_usrquota, "usrquota"},
{Opt_barrier, "barrier=%u"},
+ {Opt_metacluster, "metacluster"},
{Opt_err, NULL},
{Opt_resize, "resize"},
};
@@ -1066,6 +1070,9 @@ clear_qf_name:
case Opt_bh:
clear_opt(sbi->s_mount_opt, NOBH);
break;
+ case Opt_metacluster:
+ set_opt(sbi->s_mount_opt, METACLUSTER);
+ break;
default:
printk (KERN_ERR
"EXT3-fs: Unrecognized mount option \"%s\" "
@@ -1594,6 +1601,13 @@ static int ext3_fill_super (struct super
}
sbi->s_frags_per_block = 1;
sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
+ if (test_opt(sb, METACLUSTER)) {
+ sbi->s_nonmc_blocks_per_group = sbi->s_blocks_per_group -
+ sbi->s_blocks_per_group / 12;
+ sbi->s_nonmc_blocks_per_group &= ~7;
+ } else
+ sbi->s_nonmc_blocks_per_group = sbi->s_blocks_per_group;
+
sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
if (EXT3_INODE_SIZE(sb) == 0)
@@ -1695,6 +1709,18 @@ static int ext3_fill_super (struct super
sbi->s_rsv_window_head.rsv_goal_size = 0;
ext3_rsv_window_add(sb, &sbi->s_rsv_window_head);
+ if (test_opt(sb, METACLUSTER)) {
+ sbi->s_bginfo = kmalloc(sbi->s_groups_count *
+ sizeof(*sbi->s_bginfo), GFP_KERNEL);
+ if (!sbi->s_bginfo) {
+ printk(KERN_ERR "EXT3-fs: not enough memory\n");
+ goto failed_mount3;
+ }
+ for (i = 0; i < sbi->s_groups_count; i++)
+ sbi->s_bginfo[i].bgi_free_nonmc_blocks_count = -1;
+ } else
+ sbi->s_bginfo = NULL;
+
/*
* set up enough so that it can read an inode
*/
@@ -1720,16 +1746,16 @@ static int ext3_fill_super (struct super
if (!test_opt(sb, NOLOAD) &&
EXT3_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL)) {
if (ext3_load_journal(sb, es, journal_devnum))
- goto failed_mount3;
+ goto failed_mount4;
} else if (journal_inum) {
if (ext3_create_journal(sb, es, journal_inum))
- goto failed_mount3;
+ goto failed_mount4;
} else {
if (!silent)
printk (KERN_ERR
"ext3: No journal on filesystem on %s\n",
sb->s_id);
- goto failed_mount3;
+ goto failed_mount4;
}
/* We have now updated the journal if required, so we can
@@ -1752,7 +1778,7 @@ static int ext3_fill_super (struct super
(sbi->s_journal, 0, 0, JFS_FEATURE_INCOMPAT_REVOKE)) {
printk(KERN_ERR "EXT3-fs: Journal does not support "
"requested data journaling mode\n");
- goto failed_mount4;
+ goto failed_mount5;
}
default:
break;
@@ -1775,13 +1801,13 @@ static int ext3_fill_super (struct super
if (!sb->s_root) {
printk(KERN_ERR "EXT3-fs: get root inode failed\n");
iput(root);
- goto failed_mount4;
+ goto failed_mount5;
}
if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
dput(sb->s_root);
sb->s_root = NULL;
printk(KERN_ERR "EXT3-fs: corrupt root inode, run e2fsck\n");
- goto failed_mount4;
+ goto failed_mount5;
}
ext3_setup_super (sb, es, sb->s_flags & MS_RDONLY);
@@ -1813,8 +1839,10 @@ cantfind_ext3:
sb->s_id);
goto failed_mount;
-failed_mount4:
+failed_mount5:
journal_destroy(sbi->s_journal);
+failed_mount4:
+ kfree(sbi->s_bginfo);
failed_mount3:
percpu_counter_destroy(&sbi->s_freeblocks_counter);
percpu_counter_destroy(&sbi->s_freeinodes_counter);
diff -rupdN linux-2.6.23.13-clean/include/linux/ext3_fs.h linux-2.6.23.13-ext3mc/include/linux/ext3_fs.h
--- linux-2.6.23.13-clean/include/linux/ext3_fs.h 2008-01-09 12:18:17.000000000 -0500
+++ linux-2.6.23.13-ext3mc/include/linux/ext3_fs.h 2008-01-12 22:30:19.000000000 -0500
@@ -384,6 +384,7 @@ struct ext3_inode {
#define EXT3_MOUNT_QUOTA 0x80000 /* Some quota option set */
#define EXT3_MOUNT_USRQUOTA 0x100000 /* "old" user quota */
#define EXT3_MOUNT_GRPQUOTA 0x200000 /* "old" group quota */
+#define EXT3_MOUNT_METACLUSTER 0x400000 /* Indirect block clustering */
/* Compatibility, for having both ext2_fs.h and ext3_fs.h included at once */
#ifndef _LINUX_EXT2_FS_H
@@ -497,6 +498,7 @@ struct ext3_super_block {
#ifdef __KERNEL__
#include <linux/ext3_fs_i.h>
#include <linux/ext3_fs_sb.h>
+#include <linux/buffer_head.h>
static inline struct ext3_sb_info * EXT3_SB(struct super_block *sb)
{
return sb->s_fs_info;
@@ -732,6 +734,11 @@ struct dir_private_info {
__u32 next_hash;
};
+/* Special bh flag used by the metacluster readahead logic. */
+enum ext3_bh_state_bits {
+ EXT3_BH_PREFETCH = BH_JBD_Sentinel,
+};
+
/* calculate the first block number of the group */
static inline ext3_fsblk_t
ext3_group_first_block_no(struct super_block *sb, unsigned long group_no)
@@ -740,6 +747,24 @@ ext3_group_first_block_no(struct super_b
le32_to_cpu(EXT3_SB(sb)->s_es->s_first_data_block);
}
+static inline void
+ext3_set_buffer_prefetch(struct buffer_head *bh)
+{
+ set_bit(EXT3_BH_PREFETCH, &bh->b_state);
+}
+
+static inline void
+ext3_clear_buffer_prefetch(struct buffer_head *bh)
+{
+ clear_bit(EXT3_BH_PREFETCH, &bh->b_state);
+}
+
+static inline int
+ext3_buffer_prefetch(struct buffer_head *bh)
+{
+ return test_bit(EXT3_BH_PREFETCH, &bh->b_state);
+}
+
/*
* Special error return code only used by dx_probe() and its callers.
*/
@@ -762,8 +787,9 @@ extern int ext3_bg_has_super(struct supe
extern unsigned long ext3_bg_num_gdb(struct super_block *sb, int group);
extern ext3_fsblk_t ext3_new_block (handle_t *handle, struct inode *inode,
ext3_fsblk_t goal, int *errp);
-extern ext3_fsblk_t ext3_new_blocks (handle_t *handle, struct inode *inode,
- ext3_fsblk_t goal, unsigned long *count, int *errp);
+extern int ext3_new_blocks(handle_t *handle, struct inode *inode,
+ ext3_fsblk_t goal, int indirect_blks, int blks,
+ ext3_fsblk_t new_blocks[], int *errp);
extern void ext3_free_blocks (handle_t *handle, struct inode *inode,
ext3_fsblk_t block, unsigned long count);
extern void ext3_free_blocks_sb (handle_t *handle, struct super_block *sb,
diff -rupdN linux-2.6.23.13-clean/include/linux/ext3_fs_sb.h linux-2.6.23.13-ext3mc/include/linux/ext3_fs_sb.h
--- linux-2.6.23.13-clean/include/linux/ext3_fs_sb.h 2008-01-09 12:18:17.000000000 -0500
+++ linux-2.6.23.13-ext3mc/include/linux/ext3_fs_sb.h 2008-01-12 22:30:19.000000000 -0500
@@ -24,6 +24,8 @@
#endif
#include <linux/rbtree.h>
+struct ext3_bg_info;
+
/*
* third extended-fs super-block data in memory
*/
@@ -33,6 +35,7 @@ struct ext3_sb_info {
unsigned long s_inodes_per_block;/* Number of inodes per block */
unsigned long s_frags_per_group;/* Number of fragments in a group */
unsigned long s_blocks_per_group;/* Number of blocks in a group */
+ unsigned long s_nonmc_blocks_per_group;/* Number of non-metacluster blocks in a group */
unsigned long s_inodes_per_group;/* Number of inodes in a group */
unsigned long s_itb_per_group; /* Number of inode table blocks per group */
unsigned long s_gdb_count; /* Number of group descriptor blocks */
@@ -66,6 +69,9 @@ struct ext3_sb_info {
struct rb_root s_rsv_window_root;
struct ext3_reserve_window_node s_rsv_window_head;
+ /* array of per-bg in-memory info */
+ struct ext3_bg_info *s_bginfo;
+
/* Journaling */
struct inode * s_journal_inode;
struct journal_s * s_journal;
@@ -82,4 +88,11 @@ struct ext3_sb_info {
#endif
};
+/*
+ * in-memory data associated with each block group.
+ */
+struct ext3_bg_info {
+ int bgi_free_nonmc_blocks_count;/* Number of free non-metacluster blocks in group */
+};
+
#endif /* _LINUX_EXT3_FS_SB */
diff -rupdN linux-2.6.23.13-clean/include/linux/jbd.h linux-2.6.23.13-ext3mc/include/linux/jbd.h
--- linux-2.6.23.13-clean/include/linux/jbd.h 2008-01-09 12:18:17.000000000 -0500
+++ linux-2.6.23.13-ext3mc/include/linux/jbd.h 2008-01-12 22:30:19.000000000 -0500
@@ -307,6 +307,7 @@ enum jbd_state_bits {
BH_State, /* Pins most journal_head state */
BH_JournalHead, /* Pins bh->b_private and jh->b_bh */
BH_Unshadow, /* Dummy bit, for BJ_Shadow wakeup filtering */
+ BH_JBD_Sentinel, /* Start bit for clients of jbd */
};
BUFFER_FNS(JBD, jbd)