From 69917e431210f8712fe050f47b7561e7dae89521 Mon Sep 17 00:00:00 2001
From: Liu Bo <liub.liubo@gmail.com>
Date: Fri, 7 Sep 2012 20:01:28 -0600
Subject: Btrfs: fix a bug in parsing return value in logical resolve
In logical resolve, we parse extent_from_logical()'s 'ret' as a kind of flag.
It is possible to lose our errors because
(-EXXXX & BTRFS_EXTENT_FLAG_TREE_BLOCK) is true.
I'm not sure if it is on purpose, it just looks too hacky if it is.
I'd rather use a real flag and a 'ret' to catch errors.
Acked-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Liu Bo <liub.liubo@gmail.com>
---
fs/btrfs/backref.c | 24 ++++++++++++++++--------
fs/btrfs/backref.h | 3 ++-
fs/btrfs/ioctl.c | 6 ++++--
fs/btrfs/scrub.c | 14 ++++++++------
fs/btrfs/send.c | 7 ++++---
5 files changed, 34 insertions(+), 20 deletions(-)
(limited to 'fs')
diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index e600857d3ca..ab286e5bfe3 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -1193,7 +1193,8 @@ char *btrfs_iref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path,
* tree blocks and <0 on error.
*/
int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical,
- struct btrfs_path *path, struct btrfs_key *found_key)
+ struct btrfs_path *path, struct btrfs_key *found_key,
+ u64 *flags_ret)
{
int ret;
u64 flags;
@@ -1237,10 +1238,17 @@ int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical,
(unsigned long long)found_key->objectid,
(unsigned long long)found_key->offset,
(unsigned long long)flags, item_size);
- if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
- return BTRFS_EXTENT_FLAG_TREE_BLOCK;
- if (flags & BTRFS_EXTENT_FLAG_DATA)
- return BTRFS_EXTENT_FLAG_DATA;
+
+ WARN_ON(!flags_ret);
+ if (flags_ret) {
+ if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
+ *flags_ret = BTRFS_EXTENT_FLAG_TREE_BLOCK;
+ else if (flags & BTRFS_EXTENT_FLAG_DATA)
+ *flags_ret = BTRFS_EXTENT_FLAG_DATA;
+ else
+ BUG_ON(1);
+ return 0;
+ }
return -EIO;
}
@@ -1433,15 +1441,15 @@ int iterate_inodes_from_logical(u64 logical, struct btrfs_fs_info *fs_info,
{
int ret;
u64 extent_item_pos;
+ u64 flags = 0;
struct btrfs_key found_key;
int search_commit_root = path->search_commit_root;
- ret = extent_from_logical(fs_info, logical, path,
- &found_key);
+ ret = extent_from_logical(fs_info, logical, path, &found_key, &flags);
btrfs_release_path(path);
if (ret < 0)
return ret;
- if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK)
+ if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
return -EINVAL;
extent_item_pos = logical - found_key.objectid;
diff --git a/fs/btrfs/backref.h b/fs/btrfs/backref.h
index 032f4dc7eab..4fda5d8029a 100644
--- a/fs/btrfs/backref.h
+++ b/fs/btrfs/backref.h
@@ -40,7 +40,8 @@ int inode_item_info(u64 inum, u64 ioff, struct btrfs_root *fs_root,
struct btrfs_path *path);
int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical,
- struct btrfs_path *path, struct btrfs_key *found_key);
+ struct btrfs_path *path, struct btrfs_key *found_key,
+ u64 *flags);
int tree_backref_for_extent(unsigned long *ptr, struct extent_buffer *eb,
struct btrfs_extent_item *ei, u32 item_size,
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index de886ac7ba0..48ff3f7317b 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -3211,6 +3211,7 @@ static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
int ret = 0;
int size;
u64 extent_item_pos;
+ u64 flags = 0;
struct btrfs_ioctl_logical_ino_args *loi;
struct btrfs_data_container *inodes = NULL;
struct btrfs_path *path = NULL;
@@ -3240,10 +3241,11 @@ static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
goto out;
}
- ret = extent_from_logical(root->fs_info, loi->logical, path, &key);
+ ret = extent_from_logical(root->fs_info, loi->logical, path, &key,
+ &flags);
btrfs_release_path(path);
- if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK)
+ if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
ret = -ENOENT;
if (ret < 0)
goto out;
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 4e9eafe01c5..d3bb901ade4 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -352,13 +352,14 @@ static void scrub_print_warning(const char *errstr, struct scrub_block *sblock)
struct extent_buffer *eb;
struct btrfs_extent_item *ei;
struct scrub_warning swarn;
- u32 item_size;
- int ret;
+ unsigned long ptr = 0;
+ u64 extent_item_pos;
+ u64 flags = 0;
u64 ref_root;
+ u32 item_size;
u8 ref_level;
- unsigned long ptr = 0;
const int bufsize = 4096;
- u64 extent_item_pos;
+ int ret;
path = btrfs_alloc_path();
@@ -375,7 +376,8 @@ static void scrub_print_warning(const char *errstr, struct scrub_block *sblock)
if (!path || !swarn.scratch_buf || !swarn.msg_buf)
goto out;
- ret = extent_from_logical(fs_info, swarn.logical, path, &found_key);
+ ret = extent_from_logical(fs_info, swarn.logical, path, &found_key,
+ &flags);
if (ret < 0)
goto out;
@@ -387,7 +389,7 @@ static void scrub_print_warning(const char *errstr, struct scrub_block *sblock)
item_size = btrfs_item_size_nr(eb, path->slots[0]);
btrfs_release_path(path);
- if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
+ if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
do {
ret = tree_backref_for_extent(&ptr, eb, ei, item_size,
&ref_root, &ref_level);
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index e5c867996aa..c6ef070a8dc 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -1152,6 +1152,7 @@ static int find_extent_clone(struct send_ctx *sctx,
u64 disk_byte;
u64 num_bytes;
u64 extent_item_pos;
+ u64 flags = 0;
struct btrfs_file_extent_item *fi;
struct extent_buffer *eb = path->nodes[0];
struct backref_ctx *backref_ctx = NULL;
@@ -1198,13 +1199,13 @@ static int find_extent_clone(struct send_ctx *sctx,
}
logical = disk_byte + btrfs_file_extent_offset(eb, fi);
- ret = extent_from_logical(sctx->send_root->fs_info,
- disk_byte, tmp_path, &found_key);
+ ret = extent_from_logical(sctx->send_root->fs_info, disk_byte, tmp_path,
+ &found_key, &flags);
btrfs_release_path(tmp_path);
if (ret < 0)
goto out;
- if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
+ if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
ret = -EIO;
goto out;
}
--
cgit v1.2.3-18-g5258