From 76d8b277f7b715f78ee3cb09ee112563639693a5 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 28 Nov 2008 14:23:40 +1100 Subject: [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 Reviewed-by: Dave Chinner Signed-off-by: Niv Sardi --- fs/xfs/xfs_inode.c | 80 +++++++++++++++++++++++------------------------------- 1 file changed, 34 insertions(+), 46 deletions(-) (limited to 'fs/xfs/xfs_inode.c') diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c index 083395cd675..1d5c28b144a 100644 --- a/fs/xfs/xfs_inode.c +++ b/fs/xfs/xfs_inode.c @@ -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); @@ -889,15 +865,27 @@ 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 @@ -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); -- cgit v1.2.3