]> pilppa.com Git - linux-2.6-omap-h63xx.git/commitdiff
ocfs2: Add xattr bucket iteration for large numbers of EAs
authorTao Ma <tao.ma@oracle.com>
Mon, 18 Aug 2008 09:38:50 +0000 (17:38 +0800)
committerMark Fasheh <mfasheh@suse.com>
Mon, 13 Oct 2008 23:57:03 +0000 (16:57 -0700)
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 <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
fs/ocfs2/ocfs2_fs.h
fs/ocfs2/xattr.c
fs/ocfs2/xattr.h

index 98e1f8bba0e105d7a16331fa2c1b15da88ace6bc..8d5e72f2c5cfd9325431ef516b848ac873037750 100644 (file)
@@ -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__ */
 
 
index 67bebd9259e7787ff7f659c943a68c3b4c38b2f6..fb17f7fe4c66b458b11440e61121b112ec45ae80 100644 (file)
@@ -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;
+}
index ed32377be9db8c3fd67eba4f0a5b3f8600f7b9e6..02afa87d5e695acb86fe55342a399773e8170083 100644 (file)
@@ -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 */