From: Tao Ma Date: Mon, 18 Aug 2008 09:38:50 +0000 (+0800) Subject: ocfs2: Add xattr bucket iteration for large numbers of EAs X-Git-Tag: v2.6.28-rc1~572^2~41 X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=0c044f0b24b9128ba8c297149d88bd81f2e36af3;p=linux-2.6-omap-h63xx.git ocfs2: Add xattr bucket iteration for large numbers of EAs Ocfs2 breaks up xattr index tree leaves into 4k regions, called buckets. Attributes are stored within a given bucket, depending on hash value. After a discussion with Mark, we decided that the per-bucket index (xe_entry[]) would only exist in the 1st block of a bucket. Likewise, name/value pairs will not straddle more than one block. This allows the majority of operations to work directly on the buffer heads in a leaf block. This patch adds code to iterate the buckets in an EA. A new abstration of ocfs2_xattr_bucket is added. It records the bhs in this bucket and ocfs2_xattr_header. This keeps the code neat, improving readibility. Signed-off-by: Tao Ma Signed-off-by: Mark Fasheh --- diff --git a/fs/ocfs2/ocfs2_fs.h b/fs/ocfs2/ocfs2_fs.h index 98e1f8bba0e..8d5e72f2c5c 100644 --- a/fs/ocfs2/ocfs2_fs.h +++ b/fs/ocfs2/ocfs2_fs.h @@ -755,8 +755,13 @@ struct ocfs2_xattr_header { __le16 xh_count; /* contains the count of how many records are in the local xattr storage. */ - __le16 xh_reserved1; - __le32 xh_reserved2; + __le16 xh_free_start; /* current offset for storing + xattr. */ + __le16 xh_name_value_len; /* total length of name/value + length in this bucket. */ + __le16 xh_num_buckets; /* bucket nums in one extent + record, only valid in the + first bucket. */ __le64 xh_csum; struct ocfs2_xattr_entry xh_entries[0]; /* xattr entry list. */ }; @@ -793,6 +798,10 @@ struct ocfs2_xattr_tree_root { #define OCFS2_XATTR_SIZE(size) (((size) + OCFS2_XATTR_ROUND) & \ ~(OCFS2_XATTR_ROUND)) +#define OCFS2_XATTR_BUCKET_SIZE 4096 +#define OCFS2_XATTR_MAX_BLOCKS_PER_BUCKET (OCFS2_XATTR_BUCKET_SIZE \ + / OCFS2_MIN_BLOCKSIZE) + /* * On disk structure for xattr block. */ @@ -963,6 +972,17 @@ static inline u64 ocfs2_backup_super_blkno(struct super_block *sb, int index) return 0; } + +static inline u16 ocfs2_xattr_recs_per_xb(struct super_block *sb) +{ + int size; + + size = sb->s_blocksize - + offsetof(struct ocfs2_xattr_block, + xb_attrs.xb_root.xt_list.l_recs); + + return size / sizeof(struct ocfs2_extent_rec); +} #else static inline int ocfs2_fast_symlink_chars(int blocksize) { @@ -1046,6 +1066,17 @@ static inline uint64_t ocfs2_backup_super_blkno(int blocksize, int index) return 0; } + +static inline int ocfs2_xattr_recs_per_xb(int blocksize) +{ + int size; + + size = blocksize - + offsetof(struct ocfs2_xattr_block, + xb_attrs.xb_root.xt_list.l_recs); + + return size / sizeof(struct ocfs2_extent_rec); +} #endif /* __KERNEL__ */ diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c index 67bebd9259e..fb17f7fe4c6 100644 --- a/fs/ocfs2/xattr.c +++ b/fs/ocfs2/xattr.c @@ -52,6 +52,7 @@ #include "suballoc.h" #include "uptodate.h" #include "buffer_head_io.h" +#include "super.h" #include "xattr.h" @@ -60,6 +61,11 @@ struct ocfs2_xattr_def_value_root { struct ocfs2_extent_rec er; }; +struct ocfs2_xattr_bucket { + struct buffer_head *bhs[OCFS2_XATTR_MAX_BLOCKS_PER_BUCKET]; + struct ocfs2_xattr_header *xh; +}; + #define OCFS2_XATTR_ROOT_SIZE (sizeof(struct ocfs2_xattr_def_value_root)) #define OCFS2_XATTR_INLINE_SIZE 80 @@ -99,6 +105,11 @@ struct ocfs2_xattr_search { int not_found; }; +static int ocfs2_xattr_tree_list_index_block(struct inode *inode, + struct ocfs2_xattr_tree_root *xt, + char *buffer, + size_t buffer_size); + static inline struct xattr_handler *ocfs2_xattr_handler(int name_index) { struct xattr_handler *handler = NULL; @@ -483,7 +494,7 @@ static int ocfs2_xattr_block_list(struct inode *inode, size_t buffer_size) { struct buffer_head *blk_bh = NULL; - struct ocfs2_xattr_header *header = NULL; + struct ocfs2_xattr_block *xb; int ret = 0; if (!di->i_xattr_loc) @@ -503,10 +514,17 @@ static int ocfs2_xattr_block_list(struct inode *inode, goto cleanup; } - header = &((struct ocfs2_xattr_block *)blk_bh->b_data)-> - xb_attrs.xb_header; + xb = (struct ocfs2_xattr_block *)blk_bh->b_data; - ret = ocfs2_xattr_list_entries(inode, header, buffer, buffer_size); + if (!(le16_to_cpu(xb->xb_flags) & OCFS2_XATTR_INDEXED)) { + struct ocfs2_xattr_header *header = &xb->xb_attrs.xb_header; + ret = ocfs2_xattr_list_entries(inode, header, + buffer, buffer_size); + } else { + struct ocfs2_xattr_tree_root *xt = &xb->xb_attrs.xb_root; + ret = ocfs2_xattr_tree_list_index_block(inode, xt, + buffer, buffer_size); + } cleanup: brelse(blk_bh); @@ -1923,3 +1941,232 @@ cleanup: return ret; } +/* + * Find the xattr extent rec which may contains name_hash. + * e_cpos will be the first name hash of the xattr rec. + * el must be the ocfs2_xattr_header.xb_attrs.xb_root.xt_list. + */ +static int ocfs2_xattr_get_rec(struct inode *inode, + u32 name_hash, + u64 *p_blkno, + u32 *e_cpos, + u32 *num_clusters, + struct ocfs2_extent_list *el) +{ + int ret = 0, i; + struct buffer_head *eb_bh = NULL; + struct ocfs2_extent_block *eb; + struct ocfs2_extent_rec *rec = NULL; + u64 e_blkno = 0; + + if (el->l_tree_depth) { + ret = ocfs2_find_leaf(inode, el, name_hash, &eb_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + eb = (struct ocfs2_extent_block *) eb_bh->b_data; + el = &eb->h_list; + + if (el->l_tree_depth) { + ocfs2_error(inode->i_sb, + "Inode %lu has non zero tree depth in " + "xattr tree block %llu\n", inode->i_ino, + (unsigned long long)eb_bh->b_blocknr); + ret = -EROFS; + goto out; + } + } + + for (i = le16_to_cpu(el->l_next_free_rec) - 1; i >= 0; i--) { + rec = &el->l_recs[i]; + + if (le32_to_cpu(rec->e_cpos) <= name_hash) { + e_blkno = le64_to_cpu(rec->e_blkno); + break; + } + } + + if (!e_blkno) { + ocfs2_error(inode->i_sb, "Inode %lu has bad extent " + "record (%u, %u, 0) in xattr", inode->i_ino, + le32_to_cpu(rec->e_cpos), + ocfs2_rec_clusters(el, rec)); + ret = -EROFS; + goto out; + } + + *p_blkno = le64_to_cpu(rec->e_blkno); + *num_clusters = le16_to_cpu(rec->e_leaf_clusters); + if (e_cpos) + *e_cpos = le32_to_cpu(rec->e_cpos); +out: + brelse(eb_bh); + return ret; +} + +typedef int (xattr_bucket_func)(struct inode *inode, + struct ocfs2_xattr_bucket *bucket, + void *para); + +static int ocfs2_iterate_xattr_buckets(struct inode *inode, + u64 blkno, + u32 clusters, + xattr_bucket_func *func, + void *para) +{ + int i, j, ret = 0; + int blk_per_bucket = ocfs2_blocks_per_xattr_bucket(inode->i_sb); + u32 bpc = ocfs2_xattr_buckets_per_cluster(OCFS2_SB(inode->i_sb)); + u32 num_buckets = clusters * bpc; + struct ocfs2_xattr_bucket bucket; + + memset(&bucket, 0, sizeof(bucket)); + + mlog(0, "iterating xattr buckets in %u clusters starting from %llu\n", + clusters, blkno); + + for (i = 0; i < num_buckets; i++, blkno += blk_per_bucket) { + ret = ocfs2_read_blocks(OCFS2_SB(inode->i_sb), + blkno, blk_per_bucket, + bucket.bhs, OCFS2_BH_CACHED, inode); + if (ret) { + mlog_errno(ret); + goto out; + } + + bucket.xh = (struct ocfs2_xattr_header *)bucket.bhs[0]->b_data; + /* + * The real bucket num in this series of blocks is stored + * in the 1st bucket. + */ + if (i == 0) + num_buckets = le16_to_cpu(bucket.xh->xh_num_buckets); + + mlog(0, "iterating xattr bucket %llu\n", blkno); + if (func) { + ret = func(inode, &bucket, para); + if (ret) { + mlog_errno(ret); + break; + } + } + + for (j = 0; j < blk_per_bucket; j++) + brelse(bucket.bhs[j]); + memset(&bucket, 0, sizeof(bucket)); + } + +out: + for (j = 0; j < blk_per_bucket; j++) + brelse(bucket.bhs[j]); + + return ret; +} + +struct ocfs2_xattr_tree_list { + char *buffer; + size_t buffer_size; +}; + +static int ocfs2_xattr_bucket_get_name_value(struct inode *inode, + struct ocfs2_xattr_header *xh, + int index, + int *block_off, + int *new_offset) +{ + u16 name_offset; + + if (index < 0 || index >= le16_to_cpu(xh->xh_count)) + return -EINVAL; + + name_offset = le16_to_cpu(xh->xh_entries[index].xe_name_offset); + + *block_off = name_offset >> inode->i_sb->s_blocksize_bits; + *new_offset = name_offset % inode->i_sb->s_blocksize; + + return 0; +} + +static int ocfs2_list_xattr_bucket(struct inode *inode, + struct ocfs2_xattr_bucket *bucket, + void *para) +{ + int ret = 0; + struct ocfs2_xattr_tree_list *xl = (struct ocfs2_xattr_tree_list *)para; + size_t size; + int i, block_off, new_offset; + + for (i = 0 ; i < le16_to_cpu(bucket->xh->xh_count); i++) { + struct ocfs2_xattr_entry *entry = &bucket->xh->xh_entries[i]; + struct xattr_handler *handler = + ocfs2_xattr_handler(ocfs2_xattr_get_type(entry)); + + if (handler) { + ret = ocfs2_xattr_bucket_get_name_value(inode, + bucket->xh, + i, + &block_off, + &new_offset); + if (ret) + break; + size = handler->list(inode, xl->buffer, xl->buffer_size, + bucket->bhs[block_off]->b_data + + new_offset, + entry->xe_name_len); + if (xl->buffer) { + if (size > xl->buffer_size) + return -ERANGE; + xl->buffer += size; + } + xl->buffer_size -= size; + } + } + + return ret; +} + +static int ocfs2_xattr_tree_list_index_block(struct inode *inode, + struct ocfs2_xattr_tree_root *xt, + char *buffer, + size_t buffer_size) +{ + struct ocfs2_extent_list *el = &xt->xt_list; + int ret = 0; + u32 name_hash = UINT_MAX, e_cpos = 0, num_clusters = 0; + u64 p_blkno = 0; + struct ocfs2_xattr_tree_list xl = { + .buffer = buffer, + .buffer_size = buffer_size, + }; + + if (le16_to_cpu(el->l_next_free_rec) == 0) + return 0; + + while (name_hash > 0) { + ret = ocfs2_xattr_get_rec(inode, name_hash, &p_blkno, + &e_cpos, &num_clusters, el); + if (ret) { + mlog_errno(ret); + goto out; + } + + ret = ocfs2_iterate_xattr_buckets(inode, p_blkno, num_clusters, + ocfs2_list_xattr_bucket, + &xl); + if (ret) { + mlog_errno(ret); + goto out; + } + + if (e_cpos == 0) + break; + + name_hash = e_cpos - 1; + } + + ret = buffer_size - xl.buffer_size; +out: + return ret; +} diff --git a/fs/ocfs2/xattr.h b/fs/ocfs2/xattr.h index ed32377be9d..02afa87d5e6 100644 --- a/fs/ocfs2/xattr.h +++ b/fs/ocfs2/xattr.h @@ -48,4 +48,13 @@ extern int ocfs2_xattr_set(struct inode *, int, const char *, const void *, extern int ocfs2_xattr_remove(struct inode *inode, struct buffer_head *di_bh); extern struct xattr_handler *ocfs2_xattr_handlers[]; +static inline u16 ocfs2_xattr_buckets_per_cluster(struct ocfs2_super *osb) +{ + return (1 << osb->s_clustersize_bits) / OCFS2_XATTR_BUCKET_SIZE; +} + +static inline u16 ocfs2_blocks_per_xattr_bucket(struct super_block *sb) +{ + return OCFS2_XATTR_BUCKET_SIZE / (1 << sb->s_blocksize_bits); +} #endif /* OCFS2_XATTR_H */