[XFS] stop using xfs_itobp in xfs_iread

The only caller of xfs_itobp that doesn't have i_blkno setup is now
the initial inode read.  It needs access to the whole xfs_imap so using
xfs_inotobp is not an option.  Instead opencode the buffer lookup in
xfs_iread and kill all the functionality for the initial map from
xfs_itobp.

(First sent on October 21st)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
This commit is contained in:
Christoph Hellwig 2008-11-28 14:23:40 +11:00 committed by Niv Sardi
parent 23fac50f95
commit 76d8b277f7
3 changed files with 37 additions and 49 deletions

View File

@ -262,15 +262,11 @@ xfs_inotobp(
* If a non-zero error is returned, then the contents of bpp and
* dipp are undefined.
*
* If the inode is new and has not yet been initialized, use xfs_imap()
* to determine the size and location of the buffer to read from disk.
* If the inode has already been mapped to its buffer and read in once,
* then use the mapping information stored in the inode rather than
* calling xfs_imap(). This allows us to avoid the overhead of looking
* at the inode btree for small block file systems (see xfs_dilocate()).
* We can tell whether the inode has been mapped in before by comparing
* its disk block address to 0. Only uninitialized inodes will have
* 0 for the disk block address.
* The inode is expected to already been mapped to its buffer and read
* in once, thus we can use the mapping information stored in the inode
* rather than calling xfs_imap(). This allows us to avoid the overhead
* of looking at the inode btree for small block file systems
* (see xfs_dilocate()).
*/
int
xfs_itobp(
@ -279,40 +275,19 @@ xfs_itobp(
xfs_inode_t *ip,
xfs_dinode_t **dipp,
xfs_buf_t **bpp,
xfs_daddr_t bno,
uint imap_flags,
uint buf_flags)
{
xfs_imap_t imap;
xfs_buf_t *bp;
int error;
if (ip->i_blkno == (xfs_daddr_t)0) {
imap.im_blkno = bno;
error = xfs_imap(mp, tp, ip->i_ino, &imap,
XFS_IMAP_LOOKUP | imap_flags);
if (error)
return error;
ASSERT(ip->i_blkno != 0);
/*
* Fill in the fields in the inode that will be used to
* map the inode to its buffer from now on.
*/
ip->i_blkno = imap.im_blkno;
ip->i_len = imap.im_len;
ip->i_boffset = imap.im_boffset;
} else {
/*
* We've already mapped the inode once, so just use the
* mapping that we saved the first time.
*/
imap.im_blkno = ip->i_blkno;
imap.im_len = ip->i_len;
imap.im_boffset = ip->i_boffset;
}
ASSERT(bno == 0 || bno == imap.im_blkno);
imap.im_blkno = ip->i_blkno;
imap.im_len = ip->i_len;
imap.im_boffset = ip->i_boffset;
error = xfs_imap_to_bp(mp, tp, &imap, &bp, buf_flags, imap_flags);
error = xfs_imap_to_bp(mp, tp, &imap, &bp, buf_flags, 0);
if (error)
return error;
@ -882,6 +857,7 @@ xfs_iread(
xfs_buf_t *bp;
xfs_dinode_t *dip;
xfs_inode_t *ip;
xfs_imap_t imap;
int error;
ip = xfs_inode_alloc(mp, ino);
@ -889,16 +865,28 @@ xfs_iread(
return ENOMEM;
/*
* Get pointer's to the on-disk inode and the buffer containing it.
* If the inode number refers to a block outside the file system
* then xfs_itobp() will return NULL. In this case we should
* return NULL as well. Set i_blkno to 0 so that xfs_itobp() will
* know that this is a new incore inode.
* Get pointers to the on-disk inode and the buffer containing it.
*/
error = xfs_itobp(mp, tp, ip, &dip, &bp, bno, imap_flags, XFS_BUF_LOCK);
imap.im_blkno = bno;
error = xfs_imap(mp, tp, ip->i_ino, &imap,
XFS_IMAP_LOOKUP | imap_flags);
if (error)
goto out_destroy_inode;
/*
* Fill in the fields in the inode that will be used to
* map the inode to its buffer from now on.
*/
ip->i_blkno = imap.im_blkno;
ip->i_len = imap.im_len;
ip->i_boffset = imap.im_boffset;
ASSERT(bno == 0 || bno == imap.im_blkno);
error = xfs_imap_to_bp(mp, tp, &imap, &bp, XFS_BUF_LOCK, imap_flags);
if (error)
goto out_destroy_inode;
dip = (xfs_dinode_t *)xfs_buf_offset(bp, imap.im_boffset);
/*
* If we got something that isn't an inode it means someone
* (nfs or dmi) has a stale handle.
@ -1878,7 +1866,7 @@ xfs_iunlink(
* Here we put the head pointer into our next pointer,
* and then we fall through to point the head at us.
*/
error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0, 0, XFS_BUF_LOCK);
error = xfs_itobp(mp, tp, ip, &dip, &ibp, XFS_BUF_LOCK);
if (error)
return error;
@ -1960,7 +1948,7 @@ xfs_iunlink_remove(
* of dealing with the buffer when there is no need to
* change it.
*/
error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0, 0, XFS_BUF_LOCK);
error = xfs_itobp(mp, tp, ip, &dip, &ibp, XFS_BUF_LOCK);
if (error) {
cmn_err(CE_WARN,
"xfs_iunlink_remove: xfs_itobp() returned an error %d on %s. Returning error.",
@ -2022,7 +2010,7 @@ xfs_iunlink_remove(
* Now last_ibp points to the buffer previous to us on
* the unlinked list. Pull us from the list.
*/
error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0, 0, XFS_BUF_LOCK);
error = xfs_itobp(mp, tp, ip, &dip, &ibp, XFS_BUF_LOCK);
if (error) {
cmn_err(CE_WARN,
"xfs_iunlink_remove: xfs_itobp() returned an error %d on %s. Returning error.",
@ -2277,7 +2265,7 @@ xfs_ifree(
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
error = xfs_itobp(ip->i_mount, tp, ip, &dip, &ibp, 0, 0, XFS_BUF_LOCK);
error = xfs_itobp(ip->i_mount, tp, ip, &dip, &ibp, XFS_BUF_LOCK);
if (error)
return error;
@ -3191,7 +3179,7 @@ xfs_iflush(
/*
* Get the buffer containing the on-disk inode.
*/
error = xfs_itobp(mp, NULL, ip, &dip, &bp, 0, 0,
error = xfs_itobp(mp, NULL, ip, &dip, &bp,
noblock ? XFS_BUF_TRYLOCK : XFS_BUF_LOCK);
if (error || !bp) {
xfs_ifunlock(ip);

View File

@ -157,7 +157,7 @@ typedef struct xfs_icdinode {
#define XFS_IFEXTIREC 0x08 /* Indirection array of extent blocks */
/*
* Flags for xfs_inotobp, xfs_itobp(), xfs_imap() and xfs_dilocate().
* Flags for xfs_inotobp, xfs_imap() and xfs_dilocate().
*/
#define XFS_IMAP_LOOKUP 0x1
#define XFS_IMAP_BULKSTAT 0x2
@ -550,7 +550,7 @@ int xfs_inotobp(struct xfs_mount *, struct xfs_trans *,
struct xfs_buf **, int *, uint);
int xfs_itobp(struct xfs_mount *, struct xfs_trans *,
struct xfs_inode *, struct xfs_dinode **,
struct xfs_buf **, xfs_daddr_t, uint, uint);
struct xfs_buf **, uint);
void xfs_dinode_from_disk(struct xfs_icdinode *,
struct xfs_dinode *);
void xfs_dinode_to_disk(struct xfs_dinode *,

View File

@ -3169,7 +3169,7 @@ xlog_recover_process_one_iunlink(
* Get the on disk inode to find the next inode in the bucket.
*/
ASSERT(ip != NULL);
error = xfs_itobp(mp, NULL, ip, &dip, &ibp, 0, 0, XFS_BUF_LOCK);
error = xfs_itobp(mp, NULL, ip, &dip, &ibp, XFS_BUF_LOCK);
if (error)
goto fail;