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-rw-r--r--fs/ocfs2/suballoc.c111
1 files changed, 95 insertions, 16 deletions
diff --git a/fs/ocfs2/suballoc.c b/fs/ocfs2/suballoc.c
index 9619984153..f7b483f0de 100644
--- a/fs/ocfs2/suballoc.c
+++ b/fs/ocfs2/suballoc.c
@@ -50,6 +50,10 @@ struct ocfs2_suballoc_result {
u64 sr_blkno; /* The first allocated block */
unsigned int sr_bit_offset; /* The bit in the bg */
unsigned int sr_bits; /* How many bits we claimed */
+ unsigned int sr_max_contig_bits; /* The length for contiguous
+ * free bits, only available
+ * for cluster group
+ */
};
static u64 ocfs2_group_from_res(struct ocfs2_suballoc_result *res)
@@ -1272,6 +1276,26 @@ static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
return ret;
}
+u16 ocfs2_find_max_contig_free_bits(void *bitmap,
+ u16 total_bits, u16 start)
+{
+ u16 offset, free_bits;
+ u16 contig_bits = 0;
+
+ while (start < total_bits) {
+ offset = ocfs2_find_next_zero_bit(bitmap, total_bits, start);
+ if (offset == total_bits)
+ break;
+
+ start = ocfs2_find_next_bit(bitmap, total_bits, offset);
+ free_bits = start - offset;
+ if (contig_bits < free_bits)
+ contig_bits = free_bits;
+ }
+
+ return contig_bits;
+}
+
static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb,
struct buffer_head *bg_bh,
unsigned int bits_wanted,
@@ -1280,6 +1304,7 @@ static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb,
{
void *bitmap;
u16 best_offset, best_size;
+ u16 prev_best_size = 0;
int offset, start, found, status = 0;
struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
@@ -1306,6 +1331,7 @@ static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb,
/* got a zero after some ones */
found = 1;
start = offset + 1;
+ prev_best_size = best_size;
}
if (found > best_size) {
best_size = found;
@@ -1318,6 +1344,8 @@ static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb,
}
}
+ /* best_size will be allocated, we save prev_best_size */
+ res->sr_max_contig_bits = prev_best_size;
if (best_size) {
res->sr_bit_offset = best_offset;
res->sr_bits = best_size;
@@ -1335,11 +1363,16 @@ int ocfs2_block_group_set_bits(handle_t *handle,
struct ocfs2_group_desc *bg,
struct buffer_head *group_bh,
unsigned int bit_off,
- unsigned int num_bits)
+ unsigned int num_bits,
+ unsigned int max_contig_bits,
+ int fastpath)
{
int status;
void *bitmap = bg->bg_bitmap;
int journal_type = OCFS2_JOURNAL_ACCESS_WRITE;
+ unsigned int start = bit_off + num_bits;
+ u16 contig_bits;
+ struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb);
/* All callers get the descriptor via
* ocfs2_read_group_descriptor(). Any corruption is a code bug. */
@@ -1371,6 +1404,29 @@ int ocfs2_block_group_set_bits(handle_t *handle,
while(num_bits--)
ocfs2_set_bit(bit_off++, bitmap);
+ /*
+ * this is optimize path, caller set old contig value
+ * in max_contig_bits to bypass finding action.
+ */
+ if (fastpath) {
+ bg->bg_contig_free_bits = cpu_to_le16(max_contig_bits);
+ } else if (ocfs2_is_cluster_bitmap(alloc_inode)) {
+ /*
+ * Usually, the block group bitmap allocates only 1 bit
+ * at a time, while the cluster group allocates n bits
+ * each time. Therefore, we only save the contig bits for
+ * the cluster group.
+ */
+ contig_bits = ocfs2_find_max_contig_free_bits(bitmap,
+ le16_to_cpu(bg->bg_bits), start);
+ if (contig_bits > max_contig_bits)
+ max_contig_bits = contig_bits;
+ bg->bg_contig_free_bits = cpu_to_le16(max_contig_bits);
+ ocfs2_local_alloc_seen_free_bits(osb, max_contig_bits);
+ } else {
+ bg->bg_contig_free_bits = 0;
+ }
+
ocfs2_journal_dirty(handle, group_bh);
bail:
@@ -1484,7 +1540,12 @@ static int ocfs2_cluster_group_search(struct inode *inode,
BUG_ON(!ocfs2_is_cluster_bitmap(inode));
- if (gd->bg_free_bits_count) {
+ if (le16_to_cpu(gd->bg_contig_free_bits) &&
+ le16_to_cpu(gd->bg_contig_free_bits) < bits_wanted)
+ return -ENOSPC;
+
+ /* ->bg_contig_free_bits may un-initialized, so compare again */
+ if (le16_to_cpu(gd->bg_free_bits_count) >= bits_wanted) {
max_bits = le16_to_cpu(gd->bg_bits);
/* Tail groups in cluster bitmaps which aren't cpg
@@ -1528,13 +1589,6 @@ static int ocfs2_cluster_group_search(struct inode *inode,
* of bits. */
if (min_bits <= res->sr_bits)
search = 0; /* success */
- else if (res->sr_bits) {
- /*
- * Don't show bits which we'll be returning
- * for allocation to the local alloc bitmap.
- */
- ocfs2_local_alloc_seen_free_bits(osb, res->sr_bits);
- }
}
return search;
@@ -1553,7 +1607,7 @@ static int ocfs2_block_group_search(struct inode *inode,
BUG_ON(min_bits != 1);
BUG_ON(ocfs2_is_cluster_bitmap(inode));
- if (bg->bg_free_bits_count) {
+ if (le16_to_cpu(bg->bg_free_bits_count) >= bits_wanted) {
ret = ocfs2_block_group_find_clear_bits(OCFS2_SB(inode->i_sb),
group_bh, bits_wanted,
le16_to_cpu(bg->bg_bits),
@@ -1713,7 +1767,8 @@ static int ocfs2_search_one_group(struct ocfs2_alloc_context *ac,
}
ret = ocfs2_block_group_set_bits(handle, alloc_inode, gd, group_bh,
- res->sr_bit_offset, res->sr_bits);
+ res->sr_bit_offset, res->sr_bits,
+ res->sr_max_contig_bits, 0);
if (ret < 0) {
ocfs2_rollback_alloc_dinode_counts(alloc_inode, ac->ac_bh,
res->sr_bits,
@@ -1847,7 +1902,9 @@ static int ocfs2_search_chain(struct ocfs2_alloc_context *ac,
bg,
group_bh,
res->sr_bit_offset,
- res->sr_bits);
+ res->sr_bits,
+ res->sr_max_contig_bits,
+ 0);
if (status < 0) {
ocfs2_rollback_alloc_dinode_counts(alloc_inode,
ac->ac_bh, res->sr_bits, chain);
@@ -1949,7 +2006,7 @@ static int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *ac,
for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i ++) {
if (i == victim)
continue;
- if (!cl->cl_recs[i].c_free)
+ if (le32_to_cpu(cl->cl_recs[i].c_free) < bits_wanted)
continue;
ac->ac_chain = i;
@@ -2161,7 +2218,9 @@ int ocfs2_claim_new_inode_at_loc(handle_t *handle,
bg,
bg_bh,
res->sr_bit_offset,
- res->sr_bits);
+ res->sr_bits,
+ res->sr_max_contig_bits,
+ 0);
if (ret < 0) {
ocfs2_rollback_alloc_dinode_counts(ac->ac_inode,
ac->ac_bh, res->sr_bits, chain);
@@ -2380,11 +2439,13 @@ static int ocfs2_block_group_clear_bits(handle_t *handle,
struct buffer_head *group_bh,
unsigned int bit_off,
unsigned int num_bits,
+ unsigned int max_contig_bits,
void (*undo_fn)(unsigned int bit,
unsigned long *bmap))
{
int status;
unsigned int tmp;
+ u16 contig_bits;
struct ocfs2_group_desc *undo_bg = NULL;
struct journal_head *jh;
@@ -2431,6 +2492,20 @@ static int ocfs2_block_group_clear_bits(handle_t *handle,
num_bits);
}
+ /*
+ * TODO: even 'num_bits == 1' (the worst case, release 1 cluster),
+ * we still need to rescan whole bitmap.
+ */
+ if (ocfs2_is_cluster_bitmap(alloc_inode)) {
+ contig_bits = ocfs2_find_max_contig_free_bits(bg->bg_bitmap,
+ le16_to_cpu(bg->bg_bits), 0);
+ if (contig_bits > max_contig_bits)
+ max_contig_bits = contig_bits;
+ bg->bg_contig_free_bits = cpu_to_le16(max_contig_bits);
+ } else {
+ bg->bg_contig_free_bits = 0;
+ }
+
if (undo_fn)
spin_unlock(&jh->b_state_lock);
@@ -2457,6 +2532,7 @@ static int _ocfs2_free_suballoc_bits(handle_t *handle,
struct ocfs2_chain_list *cl = &fe->id2.i_chain;
struct buffer_head *group_bh = NULL;
struct ocfs2_group_desc *group;
+ __le16 old_bg_contig_free_bits = 0;
/* The alloc_bh comes from ocfs2_free_dinode() or
* ocfs2_free_clusters(). The callers have all locked the
@@ -2481,9 +2557,11 @@ static int _ocfs2_free_suballoc_bits(handle_t *handle,
BUG_ON((count + start_bit) > le16_to_cpu(group->bg_bits));
+ if (ocfs2_is_cluster_bitmap(alloc_inode))
+ old_bg_contig_free_bits = group->bg_contig_free_bits;
status = ocfs2_block_group_clear_bits(handle, alloc_inode,
group, group_bh,
- start_bit, count, undo_fn);
+ start_bit, count, 0, undo_fn);
if (status < 0) {
mlog_errno(status);
goto bail;
@@ -2494,7 +2572,8 @@ static int _ocfs2_free_suballoc_bits(handle_t *handle,
if (status < 0) {
mlog_errno(status);
ocfs2_block_group_set_bits(handle, alloc_inode, group, group_bh,
- start_bit, count);
+ start_bit, count,
+ le16_to_cpu(old_bg_contig_free_bits), 1);
goto bail;
}