ocfs2: Wrap inode block reads in a dedicated function.
The ocfs2 code currently reads inodes off disk with a simple
ocfs2_read_block() call. Each place that does this has a different set
of sanity checks it performs. Some check only the signature. A couple
validate the block number (the block read vs di->i_blkno). A couple
others check for VALID_FL. Only one place validates i_fs_generation. A
couple check nothing. Even when an error is found, they don't all do
the same thing.
We wrap inode reading into ocfs2_read_inode_block(). This will validate
all the above fields, going readonly if they are invalid (they never
should be). ocfs2_read_inode_block_full() is provided for the places
that want to pass read_block flags. Every caller is passing a struct
inode with a valid ip_blkno, so we don't need a separate blkno argument
either.
We will remove the validation checks from the rest of the code in a
later commit, as they are no longer necessary.
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
index 7aa00d5..9eb701b8 100644
--- a/fs/ocfs2/inode.c
+++ b/fs/ocfs2/inode.c
@@ -214,12 +214,11 @@
return 0;
}
-int ocfs2_populate_inode(struct inode *inode, struct ocfs2_dinode *fe,
- int create_ino)
+void ocfs2_populate_inode(struct inode *inode, struct ocfs2_dinode *fe,
+ int create_ino)
{
struct super_block *sb;
struct ocfs2_super *osb;
- int status = -EINVAL;
int use_plocks = 1;
mlog_entry("(0x%p, size:%llu)\n", inode,
@@ -232,25 +231,17 @@
ocfs2_mount_local(osb) || !ocfs2_stack_supports_plocks())
use_plocks = 0;
- /* this means that read_inode cannot create a superblock inode
- * today. change if needed. */
- if (!OCFS2_IS_VALID_DINODE(fe) ||
- !(fe->i_flags & cpu_to_le32(OCFS2_VALID_FL))) {
- mlog(0, "Invalid dinode: i_ino=%lu, i_blkno=%llu, "
- "signature = %.*s, flags = 0x%x\n",
- inode->i_ino,
- (unsigned long long)le64_to_cpu(fe->i_blkno), 7,
- fe->i_signature, le32_to_cpu(fe->i_flags));
- goto bail;
- }
+ /*
+ * These have all been checked by ocfs2_read_inode_block() or set
+ * by ocfs2_mknod_locked(), so a failure is a code bug.
+ */
+ BUG_ON(!OCFS2_IS_VALID_DINODE(fe)); /* This means that read_inode
+ cannot create a superblock
+ inode today. change if
+ that is needed. */
+ BUG_ON(!(fe->i_flags & cpu_to_le32(OCFS2_VALID_FL)));
+ BUG_ON(le32_to_cpu(fe->i_fs_generation) != osb->fs_generation);
- if (le32_to_cpu(fe->i_fs_generation) != osb->fs_generation) {
- mlog(ML_ERROR, "file entry generation does not match "
- "superblock! osb->fs_generation=%x, "
- "fe->i_fs_generation=%x\n",
- osb->fs_generation, le32_to_cpu(fe->i_fs_generation));
- goto bail;
- }
OCFS2_I(inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
OCFS2_I(inode)->ip_attr = le32_to_cpu(fe->i_attr);
@@ -354,10 +345,7 @@
ocfs2_set_inode_flags(inode);
- status = 0;
-bail:
- mlog_exit(status);
- return status;
+ mlog_exit_void();
}
static int ocfs2_read_locked_inode(struct inode *inode,
@@ -460,11 +448,14 @@
}
}
- if (can_lock)
- status = ocfs2_read_blocks(inode, args->fi_blkno, 1, &bh,
- OCFS2_BH_IGNORE_CACHE);
- else
+ if (can_lock) {
+ status = ocfs2_read_inode_block_full(inode, &bh,
+ OCFS2_BH_IGNORE_CACHE);
+ } else {
status = ocfs2_read_blocks_sync(osb, args->fi_blkno, 1, &bh);
+ if (!status)
+ status = ocfs2_validate_inode_block(osb->sb, bh);
+ }
if (status < 0) {
mlog_errno(status);
goto bail;
@@ -472,12 +463,6 @@
status = -EINVAL;
fe = (struct ocfs2_dinode *) bh->b_data;
- if (!OCFS2_IS_VALID_DINODE(fe)) {
- mlog(0, "Invalid dinode #%llu: signature = %.*s\n",
- (unsigned long long)args->fi_blkno, 7,
- fe->i_signature);
- goto bail;
- }
/*
* This is a code bug. Right now the caller needs to
@@ -491,10 +476,9 @@
if (S_ISCHR(le16_to_cpu(fe->i_mode)) ||
S_ISBLK(le16_to_cpu(fe->i_mode)))
- inode->i_rdev = huge_decode_dev(le64_to_cpu(fe->id1.dev1.i_rdev));
+ inode->i_rdev = huge_decode_dev(le64_to_cpu(fe->id1.dev1.i_rdev));
- if (ocfs2_populate_inode(inode, fe, 0) < 0)
- goto bail;
+ ocfs2_populate_inode(inode, fe, 0);
BUG_ON(args->fi_blkno != le64_to_cpu(fe->i_blkno));
@@ -1264,3 +1248,79 @@
spin_unlock(&OCFS2_I(inode)->ip_lock);
}
+
+int ocfs2_validate_inode_block(struct super_block *sb,
+ struct buffer_head *bh)
+{
+ int rc = -EINVAL;
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)bh->b_data;
+
+ BUG_ON(!buffer_uptodate(bh));
+
+ if (!OCFS2_IS_VALID_DINODE(di)) {
+ ocfs2_error(sb, "Invalid dinode #%llu: signature = %.*s\n",
+ (unsigned long long)bh->b_blocknr, 7,
+ di->i_signature);
+ goto bail;
+ }
+
+ if (le64_to_cpu(di->i_blkno) != bh->b_blocknr) {
+ ocfs2_error(sb, "Invalid dinode #%llu: i_blkno is %llu\n",
+ (unsigned long long)bh->b_blocknr,
+ (unsigned long long)le64_to_cpu(di->i_blkno));
+ goto bail;
+ }
+
+ if (!(di->i_flags & cpu_to_le32(OCFS2_VALID_FL))) {
+ ocfs2_error(sb,
+ "Invalid dinode #%llu: OCFS2_VALID_FL not set\n",
+ (unsigned long long)bh->b_blocknr);
+ goto bail;
+ }
+
+ if (le32_to_cpu(di->i_fs_generation) !=
+ OCFS2_SB(sb)->fs_generation) {
+ ocfs2_error(sb,
+ "Invalid dinode #%llu: fs_generation is %u\n",
+ (unsigned long long)bh->b_blocknr,
+ le32_to_cpu(di->i_fs_generation));
+ goto bail;
+ }
+
+ rc = 0;
+
+bail:
+ return rc;
+}
+
+int ocfs2_read_inode_block_full(struct inode *inode, struct buffer_head **bh,
+ int flags)
+{
+ int rc;
+ struct buffer_head *tmp = *bh;
+
+ rc = ocfs2_read_blocks(inode, OCFS2_I(inode)->ip_blkno, 1, &tmp,
+ flags);
+ if (rc)
+ goto out;
+
+ if (!(flags & OCFS2_BH_READAHEAD)) {
+ rc = ocfs2_validate_inode_block(inode->i_sb, tmp);
+ if (rc) {
+ brelse(tmp);
+ goto out;
+ }
+ }
+
+ /* If ocfs2_read_blocks() got us a new bh, pass it up. */
+ if (!*bh)
+ *bh = tmp;
+
+out:
+ return rc;
+}
+
+int ocfs2_read_inode_block(struct inode *inode, struct buffer_head **bh)
+{
+ return ocfs2_read_inode_block_full(inode, bh, 0);
+}
