ocfs2: Validate metadata only when it's read from disk.

Add an optional validation hook to ocfs2_read_blocks().  Now the
validation function is only called when a block was actually read off of
disk.  It is not called when the buffer was in cache.

We add a buffer state bit BH_NeedsValidate to flag these buffers.  It
must always be one higher than the last JBD2 buffer state bit.

The dinode, dirblock, extent_block, and xattr_block validators are
lifted to this scheme directly.  The group_descriptor validator needs to
be split into two pieces.  The first part only needs the gd buffer and
is passed to ocfs2_read_block().  The second part requires the dinode as
well, and is called every time.  It's only 3 compares, so it's tiny.
This also allows us to clean up the non-fatal gd check used by resize.c.
It now has no magic argument.

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 14:49:19 -08:00
committed by Mark Fasheh
parent 4ae1d69bed
commit 970e4936d7
10 changed files with 149 additions and 97 deletions

View File

@ -165,16 +165,15 @@ void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac);
u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster);
/*
* By default, ocfs2_validate_group_descriptor() calls ocfs2_error() when it
* By default, ocfs2_read_group_descriptor() calls ocfs2_error() when it
* finds a problem. A caller that wants to check a group descriptor
* without going readonly passes a nonzero clean_error. This is only
* resize, really. Everyone else should be using
* ocfs2_read_group_descriptor().
* without going readonly should read the block with ocfs2_read_block[s]()
* and then checking it with this function. This is only resize, really.
* Everyone else should be using ocfs2_read_group_descriptor().
*/
int ocfs2_validate_group_descriptor(struct super_block *sb,
struct ocfs2_dinode *di,
struct buffer_head *bh,
int clean_error);
int ocfs2_check_group_descriptor(struct super_block *sb,
struct ocfs2_dinode *di,
struct buffer_head *bh);
/*
* Read a group descriptor block into *bh. If *bh is NULL, a bh will be
* allocated. This is a cached read. The descriptor will be validated with