Given a physical cpos and length, decrement the refcount in the tree. If the refcount for any portion of the extent goes to zero, that portion is queued for freeing.
Signed-off-by: Tao Ma <[email protected]> --- fs/ocfs2/refcounttree.c | 227 ++++++++++++++++++++++++++++++++++++++++++++++- fs/ocfs2/refcounttree.h | 4 + 2 files changed, 229 insertions(+), 2 deletions(-) diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c index bc4bfb8..58b2c12 100644 --- a/fs/ocfs2/refcounttree.c +++ b/fs/ocfs2/refcounttree.c @@ -603,6 +603,10 @@ static void ocfs2_refcount_rec_merge(struct ocfs2_refcount_block *rb, ocfs2_rotate_refcount_rec_left(rb, index); } +/* + * Change the refcount indexed by "index" in ref_bh. + * If refcount reaches 0, remove it. + */ static int ocfs2_change_refcount_rec(handle_t *handle, struct ocfs2_caching_info *ci, struct buffer_head *ref_leaf_bh, @@ -611,7 +615,8 @@ static int ocfs2_change_refcount_rec(handle_t *handle, int ret; struct ocfs2_refcount_block *rb = (struct ocfs2_refcount_block *)ref_leaf_bh->b_data; - struct ocfs2_refcount_rec *rec = &rb->rf_records.rl_recs[index]; + struct ocfs2_refcount_list *rl = &rb->rf_records; + struct ocfs2_refcount_rec *rec = &rl->rl_recs[index]; ret = ocfs2_journal_access_rb(handle, ci, ref_leaf_bh, OCFS2_JOURNAL_ACCESS_WRITE); @@ -624,7 +629,18 @@ static int ocfs2_change_refcount_rec(handle_t *handle, le32_to_cpu(rec->r_refcount), change); le32_add_cpu(&rec->r_refcount, change); - ocfs2_refcount_rec_merge(rb, index); + if (!rec->r_refcount) { + if (index != le16_to_cpu(rl->rl_used) - 1) { + memmove(rec, rec + 1, + (le16_to_cpu(rl->rl_used) - index - 1) * + sizeof(struct ocfs2_refcount_rec)); + memset(&rl->rl_recs[le16_to_cpu(rl->rl_used) - 1], + 0, sizeof(struct ocfs2_refcount_rec)); + } + + le16_add_cpu(&rl->rl_used, -1); + } else + ocfs2_refcount_rec_merge(rb, index); ret = ocfs2_journal_dirty(handle, ref_leaf_bh); if (ret) @@ -1288,3 +1304,210 @@ out: brelse(ref_leaf_bh); return ret; } + +static int ocfs2_remove_refcount_extent(handle_t *handle, + struct ocfs2_caching_info *ci, + struct buffer_head *ref_root_bh, + struct buffer_head *ref_leaf_bh, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_cached_dealloc_ctxt *dealloc) +{ + int ret; + struct super_block *sb = ocfs2_metadata_cache_get_super(ci); + struct ocfs2_refcount_block *rb = + (struct ocfs2_refcount_block *)ref_leaf_bh->b_data; + struct ocfs2_extent_tree et; + + BUG_ON(rb->rf_records.rl_used); + + ocfs2_init_refcount_extent_tree(&et, ci, ref_root_bh); + ret = ocfs2_remove_extent(handle, &et, le32_to_cpu(rb->rf_cpos), + 1, meta_ac, dealloc); + if (ret) { + mlog_errno(ret); + goto out; + } + + ret = ocfs2_journal_access_rb(handle, ci, ref_root_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto out; + } + + rb = (struct ocfs2_refcount_block *)ref_root_bh->b_data; + + le32_add_cpu(&rb->rf_clusters, -1); + + /* + * check whether we need to restore the root refcount block if + * there is no leaf extent block at atll. + */ + if (!rb->rf_list.l_next_free_rec) { + BUG_ON(rb->rf_clusters); + + mlog(0, "reset refcount block root %llu to a leaf block.\n", + (unsigned long long)ref_root_bh->b_blocknr); + + memset(&rb->rf_records, 0, sb->s_blocksize - + offsetof(struct ocfs2_refcount_block, rf_records)); + rb->rf_flags = cpu_to_le32(OCFS2_REFCOUNT_LEAF_FL); + rb->rf_records.rl_count = + cpu_to_le16(ocfs2_refcount_recs_per_rb(sb)); + } + + ocfs2_journal_dirty(handle, ref_root_bh); + +out: + return ret; +} + +static int ocfs2_decrease_refcount_rec(handle_t *handle, + struct ocfs2_caching_info *ci, + struct buffer_head *ref_root_bh, + struct buffer_head *ref_leaf_bh, + int index, u64 cpos, unsigned int len, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_cached_dealloc_ctxt *dealloc) +{ + int ret; + struct ocfs2_refcount_block *rb = + (struct ocfs2_refcount_block *)ref_leaf_bh->b_data; + struct ocfs2_refcount_rec *rec = &rb->rf_records.rl_recs[index]; + + BUG_ON(cpos < le64_to_cpu(rec->r_cpos)); + BUG_ON(cpos + len > + le64_to_cpu(rec->r_cpos) + le32_to_cpu(rec->r_clusters)); + + if (cpos == le64_to_cpu(rec->r_cpos) && cpos + len == + le64_to_cpu(rec->r_cpos) + le32_to_cpu(rec->r_clusters)) + ret = ocfs2_change_refcount_rec(handle, ci, + ref_leaf_bh, index, -1); + else { + struct ocfs2_refcount_rec split = *rec; + split.r_cpos = cpu_to_le64(cpos); + split.r_clusters = cpu_to_le32(len); + + le32_add_cpu(&split.r_refcount, -1); + + mlog(0, "split refcount rec, start %llu, " + "len %u, count %u, original start %llu, len %u\n", + (unsigned long long)le64_to_cpu(split.r_cpos), + len, le32_to_cpu(split.r_refcount), + (unsigned long long)le64_to_cpu(rec->r_cpos), + le32_to_cpu(rec->r_clusters)); + ret = ocfs2_split_refcount_rec(handle, ci, + ref_root_bh, ref_leaf_bh, + &split, index, + meta_ac, dealloc); + } + + if (ret) { + mlog_errno(ret); + goto out; + } + + /* Remove the leaf refcount block if it contains no refcount record. */ + if (!rb->rf_records.rl_used && ref_leaf_bh != ref_root_bh) { + ret = ocfs2_remove_refcount_extent(handle, ci, ref_root_bh, + ref_leaf_bh, meta_ac, + dealloc); + if (ret) + mlog_errno(ret); + } + +out: + return ret; +} + +static int __ocfs2_decrease_refcount(handle_t *handle, + struct ocfs2_caching_info *ci, + struct buffer_head *ref_root_bh, + u64 cpos, u32 len, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_cached_dealloc_ctxt *dealloc) +{ + int ret = 0, index = 0; + struct ocfs2_refcount_rec rec; + unsigned int r_count = 0, r_len; + struct super_block *sb = ocfs2_metadata_cache_get_super(ci); + struct buffer_head *ref_leaf_bh = NULL; + + mlog(0, "Tree owner %llu, decrease refcount start %llu, len %u\n", + (unsigned long long)ocfs2_metadata_cache_owner(ci), + (unsigned long long)cpos, len); + + while (len) { + ret = ocfs2_get_refcount_rec(ci, ref_root_bh, + cpos, len, &rec, &index, + &ref_leaf_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + r_count = le32_to_cpu(rec.r_refcount); + BUG_ON(r_count == 0); + + r_len = min((u64)(cpos + len), le64_to_cpu(rec.r_cpos) + + le32_to_cpu(rec.r_clusters)) - cpos; + + ret = ocfs2_decrease_refcount_rec(handle, ci, ref_root_bh, + ref_leaf_bh, index, + cpos, r_len, + meta_ac, dealloc); + if (ret) { + mlog_errno(ret); + goto out; + } + + if (le32_to_cpu(rec.r_refcount) == 1) { + ret = ocfs2_cache_cluster_dealloc(dealloc, + ocfs2_clusters_to_blocks(sb, cpos), + r_len); + if (ret) { + mlog_errno(ret); + goto out; + } + } + + cpos += r_len; + len -= r_len; + brelse(ref_leaf_bh); + ref_leaf_bh = NULL; + } + +out: + brelse(ref_leaf_bh); + return ret; +} + +int ocfs2_decrease_refcount(struct inode *inode, struct buffer_head *di_bh, + handle_t *handle, u32 cpos, u32 len, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_cached_dealloc_ctxt *dealloc) +{ + int ret; + struct ocfs2_inode_info *oi = OCFS2_I(inode); + struct buffer_head *ref_root_bh = NULL; + struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data; + + BUG_ON(!(oi->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL)); + BUG_ON(!di->i_refcount_loc); + + ret = ocfs2_read_refcount_block(INODE_CACHE(inode), + le64_to_cpu(di->i_refcount_loc), + &ref_root_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + ret = __ocfs2_decrease_refcount(handle, INODE_CACHE(inode), ref_root_bh, + cpos, len, meta_ac, dealloc); + if (ret) + mlog_errno(ret); +out: + brelse(ref_root_bh); + return ret; +} diff --git a/fs/ocfs2/refcounttree.h b/fs/ocfs2/refcounttree.h index 9f4bdac..92fe116 100644 --- a/fs/ocfs2/refcounttree.h +++ b/fs/ocfs2/refcounttree.h @@ -23,4 +23,8 @@ int ocfs2_set_refcount_tree(struct inode *inode, u64 blkno); int ocfs2_remove_refcount_tree(struct inode *inode, struct buffer_head *di_bh); +int ocfs2_decrease_refcount(struct inode *inode, struct buffer_head *di_bh, + handle_t *handle, u32 cpos, u32 len, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_cached_dealloc_ctxt *dealloc); #endif /* OCFS2_REFCOUNTTREE_H */ -- 1.6.2.rc2.16.gf474c _______________________________________________ Ocfs2-devel mailing list [email protected] http://oss.oracle.com/mailman/listinfo/ocfs2-devel
