diff options
| author | Alexander Block <ablock84@googlemail.com> | 2012-07-28 14:44:34 +0400 |
|---|---|---|
| committer | Chris Mason <chris.mason@fusionio.com> | 2012-10-01 23:18:49 +0400 |
| commit | 35075bb046cc91f42a0e5336bdc07f3279061add (patch) | |
| tree | 7ed070a614d0ad0b80412e93bfefc5902706800b /fs | |
| parent | ee849c0472a9fe1dc09fe8390965d993b9c4e979 (diff) | |
| download | linux-35075bb046cc91f42a0e5336bdc07f3279061add.tar.xz | |
Btrfs: use kmalloc instead of stack for backref_ctx
Make sure to never get in trouble due to the backref_ctx
which was on the stack before.
Commit is a result of Arne's review.
Signed-off-by: Alexander Block <ablock84@googlemail.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/btrfs/send.c | 29 |
1 files changed, 18 insertions, 11 deletions
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index a25be0c1a6b9..36711123bdcf 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -1149,7 +1149,7 @@ static int find_extent_clone(struct send_ctx *sctx, u64 extent_item_pos; struct btrfs_file_extent_item *fi; struct extent_buffer *eb = path->nodes[0]; - struct backref_ctx backref_ctx; + struct backref_ctx *backref_ctx = NULL; struct clone_root *cur_clone_root; struct btrfs_key found_key; struct btrfs_path *tmp_path; @@ -1159,6 +1159,12 @@ static int find_extent_clone(struct send_ctx *sctx, if (!tmp_path) return -ENOMEM; + backref_ctx = kmalloc(sizeof(*backref_ctx), GFP_NOFS); + if (!backref_ctx) { + ret = -ENOMEM; + goto out; + } + if (data_offset >= ino_size) { /* * There may be extents that lie behind the file's size. @@ -1206,12 +1212,12 @@ static int find_extent_clone(struct send_ctx *sctx, cur_clone_root->found_refs = 0; } - backref_ctx.sctx = sctx; - backref_ctx.found = 0; - backref_ctx.cur_objectid = ino; - backref_ctx.cur_offset = data_offset; - backref_ctx.found_itself = 0; - backref_ctx.extent_len = num_bytes; + backref_ctx->sctx = sctx; + backref_ctx->found = 0; + backref_ctx->cur_objectid = ino; + backref_ctx->cur_offset = data_offset; + backref_ctx->found_itself = 0; + backref_ctx->extent_len = num_bytes; /* * The last extent of a file may be too large due to page alignment. @@ -1219,7 +1225,7 @@ static int find_extent_clone(struct send_ctx *sctx, * __iterate_backrefs work. */ if (data_offset + num_bytes >= ino_size) - backref_ctx.extent_len = ino_size - data_offset; + backref_ctx->extent_len = ino_size - data_offset; /* * Now collect all backrefs. @@ -1227,11 +1233,11 @@ static int find_extent_clone(struct send_ctx *sctx, extent_item_pos = logical - found_key.objectid; ret = iterate_extent_inodes(sctx->send_root->fs_info, found_key.objectid, extent_item_pos, 1, - __iterate_backrefs, &backref_ctx); + __iterate_backrefs, backref_ctx); if (ret < 0) goto out; - if (!backref_ctx.found_itself) { + if (!backref_ctx->found_itself) { /* found a bug in backref code? */ ret = -EIO; printk(KERN_ERR "btrfs: ERROR did not find backref in " @@ -1246,7 +1252,7 @@ verbose_printk(KERN_DEBUG "btrfs: find_extent_clone: data_offset=%llu, " "num_bytes=%llu, logical=%llu\n", data_offset, ino, num_bytes, logical); - if (!backref_ctx.found) + if (!backref_ctx->found) verbose_printk("btrfs: no clones found\n"); cur_clone_root = NULL; @@ -1271,6 +1277,7 @@ verbose_printk(KERN_DEBUG "btrfs: find_extent_clone: data_offset=%llu, " out: btrfs_free_path(tmp_path); + kfree(backref_ctx); return ret; } |