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ocfs2: Use buckets in ocfs2_xattr_bucket_find().

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Change the ocfs2_xattr_bucket_find() function to use ocfs2_xattr_bucket
as its abstraction.  This makes for more efficient reads, as buckets are
linear blocks, and also has improved caching characteristics.  It also
reads better.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
This commit is contained in:
Joel Becker 2008-10-27 15:01:54 -07:00 committed by Mark Fasheh
parent ba93712759
commit e2356a3f02
1 changed files with 31 additions and 58 deletions
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89
fs/ocfs2/xattr.c
View file

@ -2248,7 +2248,7 @@ typedef int (xattr_bucket_func)(struct inode *inode,
void *para);
static int ocfs2_find_xe_in_bucket(struct inode *inode,
struct buffer_head *header_bh,
struct ocfs2_xattr_bucket *bucket,
int name_index,
const char *name,
u32 name_hash,
@ -2256,11 +2256,9 @@ static int ocfs2_find_xe_in_bucket(struct inode *inode,
int *found)
{
int i, ret = 0, cmp = 1, block_off, new_offset;
struct ocfs2_xattr_header *xh =
(struct ocfs2_xattr_header *)header_bh->b_data;
struct ocfs2_xattr_header *xh = bucket_xh(bucket);
size_t name_len = strlen(name);
struct ocfs2_xattr_entry *xe = NULL;
struct buffer_head *name_bh = NULL;
char *xe_name;
/*
@ -2291,19 +2289,8 @@ static int ocfs2_find_xe_in_bucket(struct inode *inode,
break;
}
ret = ocfs2_read_block(inode, header_bh->b_blocknr + block_off,
&name_bh);
if (ret) {
mlog_errno(ret);
break;
}
xe_name = name_bh->b_data + new_offset;
cmp = memcmp(name, xe_name, name_len);
brelse(name_bh);
name_bh = NULL;
if (cmp == 0) {
xe_name = bucket_block(bucket, block_off) + new_offset;
if (!memcmp(name, xe_name, name_len)) {
*xe_index = i;
*found = 1;
ret = 0;
@ -2333,39 +2320,42 @@ static int ocfs2_xattr_bucket_find(struct inode *inode,
struct ocfs2_xattr_search *xs)
{
int ret, found = 0;
struct buffer_head *bh = NULL;
struct buffer_head *lower_bh = NULL;
struct ocfs2_xattr_header *xh = NULL;
struct ocfs2_xattr_entry *xe = NULL;
u16 index = 0;
u16 blk_per_bucket = ocfs2_blocks_per_xattr_bucket(inode->i_sb);
int low_bucket = 0, bucket, high_bucket;
struct ocfs2_xattr_bucket *search;
u32 last_hash;
u64 blkno;
u64 blkno, lower_blkno = 0;
ret = ocfs2_read_block(inode, p_blkno, &bh);
search = ocfs2_xattr_bucket_new(inode);
if (!search) {
ret = -ENOMEM;
mlog_errno(ret);
goto out;
}
ret = ocfs2_read_xattr_bucket(search, p_blkno);
if (ret) {
mlog_errno(ret);
goto out;
}
xh = (struct ocfs2_xattr_header *)bh->b_data;
xh = bucket_xh(search);
high_bucket = le16_to_cpu(xh->xh_num_buckets) - 1;
while (low_bucket <= high_bucket) {
brelse(bh);
bh = NULL;
ocfs2_xattr_bucket_relse(search);
bucket = (low_bucket + high_bucket) / 2;
blkno = p_blkno + bucket * blk_per_bucket;
ret = ocfs2_read_block(inode, blkno, &bh);
ret = ocfs2_read_xattr_bucket(search, blkno);
if (ret) {
mlog_errno(ret);
goto out;
}
xh = (struct ocfs2_xattr_header *)bh->b_data;
xh = bucket_xh(search);
xe = &xh->xh_entries[0];
if (name_hash < le32_to_cpu(xe->xe_name_hash)) {
high_bucket = bucket - 1;
@ -2382,10 +2372,8 @@ static int ocfs2_xattr_bucket_find(struct inode *inode,
last_hash = le32_to_cpu(xe->xe_name_hash);
/* record lower_bh which may be the insert place. */
brelse(lower_bh);
lower_bh = bh;
bh = NULL;
/* record lower_blkno which may be the insert place. */
lower_blkno = blkno;
if (name_hash > le32_to_cpu(xe->xe_name_hash)) {
low_bucket = bucket + 1;
@ -2393,7 +2381,7 @@ static int ocfs2_xattr_bucket_find(struct inode *inode,
}
/* the searched xattr should reside in this bucket if exists. */
ret = ocfs2_find_xe_in_bucket(inode, lower_bh,
ret = ocfs2_find_xe_in_bucket(inode, search,
name_index, name, name_hash,
&index, &found);
if (ret) {
@ -2408,35 +2396,21 @@ static int ocfs2_xattr_bucket_find(struct inode *inode,
* When the xattr's hash value is in the gap of 2 buckets, we will
* always set it to the previous bucket.
*/
if (!lower_bh) {
/*
* We can't find any bucket whose first name_hash is less
* than the find name_hash.
*/
BUG_ON(bh->b_blocknr != p_blkno);
lower_bh = bh;
bh = NULL;
if (!lower_blkno)
lower_blkno = p_blkno;
/* This should be in cache - we just read it during the search */
ret = ocfs2_read_xattr_bucket(xs->bucket, lower_blkno);
if (ret) {
mlog_errno(ret);
goto out;
}
xs->bucket->bu_bhs[0] = lower_bh;
lower_bh = NULL;
xs->header = bucket_xh(xs->bucket);
xs->base = bucket_block(xs->bucket, 0);
xs->end = xs->base + inode->i_sb->s_blocksize;
if (found) {
/*
* If we have found the xattr enty, read all the blocks in
* this bucket.
*/
ret = ocfs2_read_blocks(inode, bucket_blkno(xs->bucket) + 1,
blk_per_bucket - 1, &xs->bucket->bu_bhs[1],
0);
if (ret) {
mlog_errno(ret);
goto out;
}
xs->here = &xs->header->xh_entries[index];
mlog(0, "find xattr %s in bucket %llu, entry = %u\n", name,
(unsigned long long)bucket_blkno(xs->bucket), index);
@ -2444,8 +2418,7 @@ static int ocfs2_xattr_bucket_find(struct inode *inode,
ret = -ENODATA;
out:
brelse(bh);
brelse(lower_bh);
ocfs2_xattr_bucket_free(search);
return ret;
}