lkml.org 
[lkml]   [2008]   [Dec]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 37/45] ocfs2: Wrap extent block reads in a dedicated function.
Date
From: Joel Becker <joel.becker@oracle.com>

We weren't consistently checking extent blocks after we read them.
Most places checked the signature, but none checked h_blkno or
h_fs_signature. Create a toplevel ocfs2_read_extent_block() that does
the read and the validation.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
---
fs/ocfs2/alloc.c | 151 ++++++++++++++++++++++++++++++++-----------------
fs/ocfs2/alloc.h | 8 +++
fs/ocfs2/extent_map.c | 23 ++------
fs/ocfs2/ocfs2.h | 8 ---
4 files changed, 111 insertions(+), 79 deletions(-)
diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index 320545b..f430cc6 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -678,6 +678,66 @@ struct ocfs2_merge_ctxt {
int c_split_covers_rec;
};

+static int ocfs2_validate_extent_block(struct super_block *sb,
+ struct buffer_head *bh)
+{
+ struct ocfs2_extent_block *eb =
+ (struct ocfs2_extent_block *)bh->b_data;
+
+ if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
+ ocfs2_error(sb,
+ "Extent block #%llu has bad signature %.*s",
+ (unsigned long long)bh->b_blocknr, 7,
+ eb->h_signature);
+ return -EINVAL;
+ }
+
+ if (le64_to_cpu(eb->h_blkno) != bh->b_blocknr) {
+ ocfs2_error(sb,
+ "Extent block #%llu has an invalid h_blkno "
+ "of %llu",
+ (unsigned long long)bh->b_blocknr,
+ (unsigned long long)le64_to_cpu(eb->h_blkno));
+ return -EINVAL;
+ }
+
+ if (le32_to_cpu(eb->h_fs_generation) != OCFS2_SB(sb)->fs_generation) {
+ ocfs2_error(sb,
+ "Extent block #%llu has an invalid "
+ "h_fs_generation of #%u",
+ (unsigned long long)bh->b_blocknr,
+ le32_to_cpu(eb->h_fs_generation));
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+int ocfs2_read_extent_block(struct inode *inode, u64 eb_blkno,
+ struct buffer_head **bh)
+{
+ int rc;
+ struct buffer_head *tmp = *bh;
+
+ rc = ocfs2_read_block(inode, eb_blkno, &tmp);
+ if (rc)
+ goto out;
+
+ rc = ocfs2_validate_extent_block(inode->i_sb, tmp);
+ if (rc) {
+ brelse(tmp);
+ goto out;
+ }
+
+ /* If ocfs2_read_block() got us a new bh, pass it up. */
+ if (!*bh)
+ *bh = tmp;
+
+out:
+ return rc;
+}
+
+
/*
* How many free extents have we got before we need more meta data?
*/
@@ -697,8 +757,7 @@ int ocfs2_num_free_extents(struct ocfs2_super *osb,
last_eb_blk = ocfs2_et_get_last_eb_blk(et);

if (last_eb_blk) {
- retval = ocfs2_read_block(inode, last_eb_blk,
- &eb_bh);
+ retval = ocfs2_read_extent_block(inode, last_eb_blk, &eb_bh);
if (retval < 0) {
mlog_errno(retval);
goto bail;
@@ -900,11 +959,8 @@ static int ocfs2_add_branch(struct ocfs2_super *osb,
for(i = 0; i < new_blocks; i++) {
bh = new_eb_bhs[i];
eb = (struct ocfs2_extent_block *) bh->b_data;
- if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
- OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, eb);
- status = -EIO;
- goto bail;
- }
+ /* ocfs2_create_new_meta_bhs() should create it right! */
+ BUG_ON(!OCFS2_IS_VALID_EXTENT_BLOCK(eb));
eb_el = &eb->h_list;

status = ocfs2_journal_access(handle, inode, bh,
@@ -1044,11 +1100,8 @@ static int ocfs2_shift_tree_depth(struct ocfs2_super *osb,
}

eb = (struct ocfs2_extent_block *) new_eb_bh->b_data;
- if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
- OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, eb);
- status = -EIO;
- goto bail;
- }
+ /* ocfs2_create_new_meta_bhs() should create it right! */
+ BUG_ON(!OCFS2_IS_VALID_EXTENT_BLOCK(eb));

eb_el = &eb->h_list;
root_el = et->et_root_el;
@@ -1168,18 +1221,13 @@ static int ocfs2_find_branch_target(struct ocfs2_super *osb,
brelse(bh);
bh = NULL;

- status = ocfs2_read_block(inode, blkno, &bh);
+ status = ocfs2_read_extent_block(inode, blkno, &bh);
if (status < 0) {
mlog_errno(status);
goto bail;
}

eb = (struct ocfs2_extent_block *) bh->b_data;
- if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
- OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, eb);
- status = -EIO;
- goto bail;
- }
el = &eb->h_list;

if (le16_to_cpu(el->l_next_free_rec) <
@@ -1532,7 +1580,7 @@ static int __ocfs2_find_path(struct inode *inode,

brelse(bh);
bh = NULL;
- ret = ocfs2_read_block(inode, blkno, &bh);
+ ret = ocfs2_read_extent_block(inode, blkno, &bh);
if (ret) {
mlog_errno(ret);
goto out;
@@ -1540,11 +1588,6 @@ static int __ocfs2_find_path(struct inode *inode,

eb = (struct ocfs2_extent_block *) bh->b_data;
el = &eb->h_list;
- if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
- OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, eb);
- ret = -EIO;
- goto out;
- }

if (le16_to_cpu(el->l_next_free_rec) >
le16_to_cpu(el->l_count)) {
@@ -4089,8 +4132,15 @@ ocfs2_figure_merge_contig_type(struct inode *inode, struct ocfs2_path *path,
le16_to_cpu(new_el->l_count)) {
bh = path_leaf_bh(left_path);
eb = (struct ocfs2_extent_block *)bh->b_data;
- OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb,
- eb);
+ ocfs2_error(inode->i_sb,
+ "Extent block #%llu has an "
+ "invalid l_next_free_rec of "
+ "%d. It should have "
+ "matched the l_count of %d",
+ (unsigned long long)le64_to_cpu(eb->h_blkno),
+ le16_to_cpu(new_el->l_next_free_rec),
+ le16_to_cpu(new_el->l_count));
+ status = -EINVAL;
goto out;
}
rec = &new_el->l_recs[
@@ -4139,8 +4189,12 @@ ocfs2_figure_merge_contig_type(struct inode *inode, struct ocfs2_path *path,
if (le16_to_cpu(new_el->l_next_free_rec) <= 1) {
bh = path_leaf_bh(right_path);
eb = (struct ocfs2_extent_block *)bh->b_data;
- OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb,
- eb);
+ ocfs2_error(inode->i_sb,
+ "Extent block #%llu has an "
+ "invalid l_next_free_rec of %d",
+ (unsigned long long)le64_to_cpu(eb->h_blkno),
+ le16_to_cpu(new_el->l_next_free_rec));
+ status = -EINVAL;
goto out;
}
rec = &new_el->l_recs[1];
@@ -4286,7 +4340,9 @@ static int ocfs2_figure_insert_type(struct inode *inode,
* ocfs2_figure_insert_type() and ocfs2_add_branch()
* may want it later.
*/
- ret = ocfs2_read_block(inode, ocfs2_et_get_last_eb_blk(et), &bh);
+ ret = ocfs2_read_extent_block(inode,
+ ocfs2_et_get_last_eb_blk(et),
+ &bh);
if (ret) {
mlog_exit(ret);
goto out;
@@ -4752,20 +4808,15 @@ static int __ocfs2_mark_extent_written(struct inode *inode,
if (path->p_tree_depth) {
struct ocfs2_extent_block *eb;

- ret = ocfs2_read_block(inode, ocfs2_et_get_last_eb_blk(et),
- &last_eb_bh);
+ ret = ocfs2_read_extent_block(inode,
+ ocfs2_et_get_last_eb_blk(et),
+ &last_eb_bh);
if (ret) {
mlog_exit(ret);
goto out;
}

eb = (struct ocfs2_extent_block *) last_eb_bh->b_data;
- if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
- OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, eb);
- ret = -EROFS;
- goto out;
- }
-
rightmost_el = &eb->h_list;
} else
rightmost_el = path_root_el(path);
@@ -4910,8 +4961,9 @@ static int ocfs2_split_tree(struct inode *inode, struct ocfs2_extent_tree *et,

depth = path->p_tree_depth;
if (depth > 0) {
- ret = ocfs2_read_block(inode, ocfs2_et_get_last_eb_blk(et),
- &last_eb_bh);
+ ret = ocfs2_read_extent_block(inode,
+ ocfs2_et_get_last_eb_blk(et),
+ &last_eb_bh);
if (ret < 0) {
mlog_errno(ret);
goto out;
@@ -6231,11 +6283,10 @@ static int ocfs2_find_new_last_ext_blk(struct inode *inode,

eb = (struct ocfs2_extent_block *) bh->b_data;
el = &eb->h_list;
- if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
- OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, eb);
- ret = -EROFS;
- goto out;
- }
+
+ /* ocfs2_find_leaf() gets the eb from ocfs2_read_extent_block().
+ * Any corruption is a code bug. */
+ BUG_ON(!OCFS2_IS_VALID_EXTENT_BLOCK(eb));

*new_last_eb = bh;
get_bh(*new_last_eb);
@@ -7140,20 +7191,14 @@ int ocfs2_prepare_truncate(struct ocfs2_super *osb,
ocfs2_init_dealloc_ctxt(&(*tc)->tc_dealloc);

if (fe->id2.i_list.l_tree_depth) {
- status = ocfs2_read_block(inode, le64_to_cpu(fe->i_last_eb_blk),
- &last_eb_bh);
+ status = ocfs2_read_extent_block(inode,
+ le64_to_cpu(fe->i_last_eb_blk),
+ &last_eb_bh);
if (status < 0) {
mlog_errno(status);
goto bail;
}
eb = (struct ocfs2_extent_block *) last_eb_bh->b_data;
- if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
- OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, eb);
-
- brelse(last_eb_bh);
- status = -EIO;
- goto bail;
- }
}

(*tc)->tc_last_eb_bh = last_eb_bh;
diff --git a/fs/ocfs2/alloc.h b/fs/ocfs2/alloc.h
index 0fbf8fc..59d37d1 100644
--- a/fs/ocfs2/alloc.h
+++ b/fs/ocfs2/alloc.h
@@ -73,6 +73,14 @@ void ocfs2_init_xattr_value_extent_tree(struct ocfs2_extent_tree *et,
struct buffer_head *bh,
struct ocfs2_xattr_value_root *xv);

+/*
+ * Read an extent block into *bh. If *bh is NULL, a bh will be
+ * allocated. This is a cached read. The extent block will be validated
+ * with ocfs2_validate_extent_block().
+ */
+int ocfs2_read_extent_block(struct inode *inode, u64 eb_blkno,
+ struct buffer_head **bh);
+
struct ocfs2_alloc_context;
int ocfs2_insert_extent(struct ocfs2_super *osb,
handle_t *handle,
diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c
index b686b31..0bd9d96 100644
--- a/fs/ocfs2/extent_map.c
+++ b/fs/ocfs2/extent_map.c
@@ -293,7 +293,7 @@ static int ocfs2_last_eb_is_empty(struct inode *inode,
struct ocfs2_extent_block *eb;
struct ocfs2_extent_list *el;

- ret = ocfs2_read_block(inode, last_eb_blk, &eb_bh);
+ ret = ocfs2_read_extent_block(inode, last_eb_blk, &eb_bh);
if (ret) {
mlog_errno(ret);
goto out;
@@ -302,12 +302,6 @@ static int ocfs2_last_eb_is_empty(struct inode *inode,
eb = (struct ocfs2_extent_block *) eb_bh->b_data;
el = &eb->h_list;

- if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
- ret = -EROFS;
- OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, eb);
- goto out;
- }
-
if (el->l_tree_depth) {
ocfs2_error(inode->i_sb,
"Inode %lu has non zero tree depth in "
@@ -381,23 +375,16 @@ static int ocfs2_figure_hole_clusters(struct inode *inode,
if (le64_to_cpu(eb->h_next_leaf_blk) == 0ULL)
goto no_more_extents;

- ret = ocfs2_read_block(inode,
- le64_to_cpu(eb->h_next_leaf_blk),
- &next_eb_bh);
+ ret = ocfs2_read_extent_block(inode,
+ le64_to_cpu(eb->h_next_leaf_blk),
+ &next_eb_bh);
if (ret) {
mlog_errno(ret);
goto out;
}
- next_eb = (struct ocfs2_extent_block *)next_eb_bh->b_data;
-
- if (!OCFS2_IS_VALID_EXTENT_BLOCK(next_eb)) {
- ret = -EROFS;
- OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, next_eb);
- goto out;
- }

+ next_eb = (struct ocfs2_extent_block *)next_eb_bh->b_data;
el = &next_eb->h_list;
-
i = ocfs2_search_for_hole_index(el, v_cluster);
}

diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index 82ba887..f04b229 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -447,14 +447,6 @@ static inline int ocfs2_uses_extended_slot_map(struct ocfs2_super *osb)
#define OCFS2_IS_VALID_EXTENT_BLOCK(ptr) \
(!strcmp((ptr)->h_signature, OCFS2_EXTENT_BLOCK_SIGNATURE))

-#define OCFS2_RO_ON_INVALID_EXTENT_BLOCK(__sb, __eb) do { \
- typeof(__eb) ____eb = (__eb); \
- ocfs2_error((__sb), \
- "Extent Block # %llu has bad signature %.*s", \
- (unsigned long long)le64_to_cpu((____eb)->h_blkno), 7, \
- (____eb)->h_signature); \
-} while (0)
-
#define OCFS2_IS_VALID_GROUP_DESC(ptr) \
(!strcmp((ptr)->bg_signature, OCFS2_GROUP_DESC_SIGNATURE))

--
1.5.6


\
 
 \ /
  Last update: 2008-12-19 23:09    [from the cache]
©2003-2014 Jasper Spaans. Advertise on this site