From e2356a3f02cfdbce735465a2b40b6dc72a764c26 Mon Sep 17 00:00:00 2001 From: Joel Becker Date: Mon, 27 Oct 2008 15:01:54 -0700 Subject: [PATCH] ocfs2: Use buckets in ocfs2_xattr_bucket_find(). 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 Signed-off-by: Mark Fasheh --- fs/ocfs2/xattr.c | 89 +++++++++++++++++------------------------------- 1 file changed, 31 insertions(+), 58 deletions(-) diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c index 766494ed6e11..46986c635eb8 100644 --- a/fs/ocfs2/xattr.c +++ b/fs/ocfs2/xattr.c @@ -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; }