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ocfs2: Wrap inode block reads in a dedicated function.

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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>
This commit is contained in:
Joel Becker
2008-11-13 14:49:11 -08:00
committed by Mark Fasheh
parent a68979b857
commit b657c95c11
12 changed files with 136 additions and 97 deletions
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136
fs/ocfs2/inode.c
View File

@@ -214,12 +214,11 @@ static int ocfs2_init_locked_inode(struct inode *inode, void *opaque)
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 @@ int ocfs2_populate_inode(struct inode *inode, struct ocfs2_dinode *fe,
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 @@ int ocfs2_populate_inode(struct inode *inode, struct ocfs2_dinode *fe,
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 @@ static int ocfs2_read_locked_inode(struct inode *inode,
}
}
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 @@ static int ocfs2_read_locked_inode(struct inode *inode,
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 @@ static int ocfs2_read_locked_inode(struct inode *inode,
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 @@ void ocfs2_refresh_inode(struct inode *inode,
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);
}