xfs: merge xfs_itobp into xfs_imap_to_bp

All callers of xfs_imap_to_bp want the dinode pointer, so let's calculate it
inside xfs_imap_to_bp.  Once that is done xfs_itobp becomes a fairly pointless
wrapper which can be replaced with direct calls to xfs_imap_to_bp.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

5 files changed, 54 insertions, 91 deletions

diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 257f3c463e0e..34c985de5fa0 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -132,23 +132,28 @@ xfs_inobp_check(
 #endif
 
 /*
- * Find the buffer associated with the given inode map
- * We do basic validation checks on the buffer once it has been
- * retrieved from disk.
+ * This routine is called to map an inode to the buffer containing the on-disk
+ * version of the inode.  It returns a pointer to the buffer containing the
+ * on-disk inode in the bpp parameter, and in the dipp parameter it returns a
+ * pointer to the on-disk inode within that buffer.
+ *
+ * If a non-zero error is returned, then the contents of bpp and dipp are
+ * undefined.
  */
-STATIC int
+int
 xfs_imap_to_bp(
-        xfs_mount_t     *mp,
-        xfs_trans_t     *tp,
-        struct xfs_imap *imap,
-        xfs_buf_t       **bpp,
-        uint            buf_flags,
-        uint            iget_flags)
+        struct xfs_mount        *mp,
+        struct xfs_trans        *tp,
+        struct xfs_imap         *imap,
+        struct xfs_dinode       **dipp,
+        struct xfs_buf          **bpp,
+        uint                    buf_flags,
+        uint                    iget_flags)
 {
-        int             error;
-        int             i;
-        int             ni;
-        xfs_buf_t       *bp;
+        struct xfs_buf          *bp;
+        int                     error;
+        int                     i;
+        int                     ni;
 
         buf_flags |= XBF_UNMAPPED;
         error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, imap->im_blkno,
@@ -189,8 +194,8 @@ xfs_imap_to_bp(
                                 xfs_trans_brelse(tp, bp);
                                 return XFS_ERROR(EINVAL);
                         }
-                        XFS_CORRUPTION_ERROR("xfs_imap_to_bp",
-                                                XFS_ERRLEVEL_HIGH, mp, dip);
+                        XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_HIGH,
+                                             mp, dip);
 #ifdef DEBUG
                         xfs_emerg(mp,
                                 "bad inode magic/vsn daddr %lld #%d (magic=%x)",
@@ -204,7 +209,9 @@ xfs_imap_to_bp(
         }
 
         xfs_inobp_check(mp, bp);
+
         *bpp = bp;
+        *dipp = (struct xfs_dinode *)xfs_buf_offset(bp, imap->im_boffset);
         return 0;
 }
 
@@ -240,63 +247,15 @@ xfs_inotobp(
         if (error)
                 return error;
 
-        error = xfs_imap_to_bp(mp, tp, &imap, &bp, 0, imap_flags);
+        error = xfs_imap_to_bp(mp, tp, &imap, dipp, &bp, 0, imap_flags);
         if (error)
                 return error;
 
-        *dipp = (xfs_dinode_t *)xfs_buf_offset(bp, imap.im_boffset);
         *bpp = bp;
         *offset = imap.im_boffset;
         return 0;
 }
 
-
-/*
- * This routine is called to map an inode to the buffer containing
- * the on-disk version of the inode.  It returns a pointer to the
- * buffer containing the on-disk inode in the bpp parameter, and in
- * the dip parameter it returns a pointer to the on-disk inode within
- * that buffer.
- *
- * If a non-zero error is returned, then the contents of bpp and
- * dipp are undefined.
- *
- * 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_imap()).
- */
-int
-xfs_itobp(
-        xfs_mount_t     *mp,
-        xfs_trans_t     *tp,
-        xfs_inode_t     *ip,
-        xfs_dinode_t    **dipp,
-        xfs_buf_t       **bpp,
-        uint            buf_flags)
-{
-        xfs_buf_t       *bp;
-        int             error;
-
-        ASSERT(ip->i_imap.im_blkno != 0);
-
-        error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &bp, buf_flags, 0);
-        if (error)
-                return error;
-
-        if (!bp) {
-                ASSERT(buf_flags & XBF_TRYLOCK);
-                ASSERT(tp == NULL);
-                *bpp = NULL;
-                return EAGAIN;
-        }
-
-        *dipp = (xfs_dinode_t *)xfs_buf_offset(bp, ip->i_imap.im_boffset);
-        *bpp = bp;
-        return 0;
-}
-
 /*
  * Move inode type and inode format specific information from the
  * on-disk inode to the in-core inode.  For fifos, devs, and sockets
@@ -796,10 +755,9 @@ xfs_iread(
         /*
          * Get pointers to the on-disk inode and the buffer containing it.
          */
-        error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &bp, 0, iget_flags);
+        error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &bp, 0, iget_flags);
         if (error)
                 return error;
-        dip = (xfs_dinode_t *)xfs_buf_offset(bp, ip->i_imap.im_boffset);
 
         /*
          * If we got something that isn't an inode it means someone
@@ -876,7 +834,7 @@ xfs_iread(
         /*
          * Use xfs_trans_brelse() to release the buffer containing the
          * on-disk inode, because it was acquired with xfs_trans_read_buf()
-         * in xfs_itobp() above.  If tp is NULL, this is just a normal
+         * in xfs_imap_to_bp() above.  If tp is NULL, this is just a normal
          * brelse().  If we're within a transaction, then xfs_trans_brelse()
          * will only release the buffer if it is not dirty within the
          * transaction.  It will be OK to release the buffer in this case,
@@ -1355,7 +1313,8 @@ 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);
+                error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
+                                       0, 0);
                 if (error)
                         return error;
 
@@ -1429,16 +1388,16 @@ xfs_iunlink_remove(
 
         if (be32_to_cpu(agi->agi_unlinked[bucket_index]) == agino) {
                 /*
-                 * We're at the head of the list.  Get the inode's
-                 * on-disk buffer to see if there is anyone after us
-                 * on the list.  Only modify our next pointer if it
-                 * is not already NULLAGINO.  This saves us the overhead
-                 * of dealing with the buffer when there is no need to
-                 * change it.
+                 * We're at the head of the list.  Get the inode's on-disk
+                 * buffer to see if there is anyone after us on the list.
+                 * Only modify our next pointer if it is not already NULLAGINO.
+                 * This saves us the overhead of dealing with the buffer when
+                 * there is no need to change it.
                  */
-                error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0);
+                error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
+                                       0, 0);
                 if (error) {
-                        xfs_warn(mp, "%s: xfs_itobp() returned error %d.",
+                        xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.",
                                 __func__, error);
                         return error;
                 }
@@ -1493,13 +1452,15 @@ xfs_iunlink_remove(
                         ASSERT(next_agino != NULLAGINO);
                         ASSERT(next_agino != 0);
                 }
+
                 /*
-                 * Now last_ibp points to the buffer previous to us on
-                 * the unlinked list.  Pull us from the list.
+                 * 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);
+                error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
+                                       0, 0);
                 if (error) {
-                        xfs_warn(mp, "%s: xfs_itobp(2) returned error %d.",
+                        xfs_warn(mp, "%s: xfs_imap_to_bp(2) returned error %d.",
                                 __func__, error);
                         return error;
                 }
@@ -1749,7 +1710,8 @@ xfs_ifree(
 
         xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
 
-        error = xfs_itobp(ip->i_mount, tp, ip, &dip, &ibp, 0);
+        error = xfs_imap_to_bp(ip->i_mount, tp, &ip->i_imap, &dip, &ibp,
+                               0, 0);
         if (error)
                 return error;
 
@@ -2428,7 +2390,7 @@ xfs_iflush(
         /*
          * For stale inodes we cannot rely on the backing buffer remaining
          * stale in cache for the remaining life of the stale inode and so
-         * xfs_itobp() below may give us a buffer that no longer contains
+         * xfs_imap_to_bp() below may give us a buffer that no longer contains
          * inodes below. We have to check this after ensuring the inode is
          * unpinned so that it is safe to reclaim the stale inode after the
          * flush call.
@@ -2454,7 +2416,8 @@ xfs_iflush(
         /*
          * Get the buffer containing the on-disk inode.
          */
-        error = xfs_itobp(mp, NULL, ip, &dip, &bp, XBF_TRYLOCK);
+        error = xfs_imap_to_bp(mp, NULL, &ip->i_imap, &dip, &bp, XBF_TRYLOCK,
+                               0);
         if (error || !bp) {
                 xfs_ifunlock(ip);
                 return error;
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index 1efff36a75b6..942fd7f9110b 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -560,9 +560,9 @@ do { \
 int             xfs_inotobp(struct xfs_mount *, struct xfs_trans *,
                             xfs_ino_t, struct xfs_dinode **,
                             struct xfs_buf **, int *, uint);
-int             xfs_itobp(struct xfs_mount *, struct xfs_trans *,
-                          struct xfs_inode *, struct xfs_dinode **,
-                          struct xfs_buf **, uint);
+int             xfs_imap_to_bp(struct xfs_mount *, struct xfs_trans *,
+                               struct xfs_imap *, struct xfs_dinode **,
+                               struct xfs_buf **, uint, uint);
 int             xfs_iread(struct xfs_mount *, struct xfs_trans *,
                           struct xfs_inode *, uint);
 void            xfs_dinode_to_disk(struct xfs_dinode *,
diff --git a/fs/xfs/xfs_itable.c b/fs/xfs/xfs_itable.c
index eff577a9b67f..01d10a66e302 100644
--- a/fs/xfs/xfs_itable.c
+++ b/fs/xfs/xfs_itable.c
@@ -555,7 +555,7 @@ xfs_bulkstat_single(
 
         /*
          * note that requesting valid inode numbers which are not allocated
-         * to inodes will most likely cause xfs_itobp to generate warning
+         * to inodes will most likely cause xfs_imap_to_bp to generate warning
          * messages about bad magic numbers. This is ok. The fact that
          * the inode isn't actually an inode is handled by the
          * error check below. Done this way to make the usual case faster
diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index a76ba886e738..5da3ace352bf 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -3106,7 +3106,7 @@ xlog_recover_process_one_iunlink(
         /*
          * Get the on disk inode to find the next inode in the bucket.
          */
-        error = xfs_itobp(mp, NULL, ip, &dip, &ibp, 0);
+        error = xfs_imap_to_bp(mp, NULL, &ip->i_imap, &dip, &ibp, 0, 0);
         if (error)
                 goto fail_iput;
 
diff --git a/fs/xfs/xfs_sync.c b/fs/xfs/xfs_sync.c
index 1e9ee064dbb2..e61fc1519073 100644
--- a/fs/xfs/xfs_sync.c
+++ b/fs/xfs/xfs_sync.c
@@ -712,8 +712,8 @@ restart:
          * Note that xfs_iflush will never block on the inode buffer lock, as
          * xfs_ifree_cluster() can lock the inode buffer before it locks the
          * ip->i_lock, and we are doing the exact opposite here.  As a result,
-         * doing a blocking xfs_itobp() to get the cluster buffer would result
-         * in an ABBA deadlock with xfs_ifree_cluster().
+         * doing a blocking xfs_imap_to_bp() to get the cluster buffer would
+         * result in an ABBA deadlock with xfs_ifree_cluster().
          *
          * As xfs_ifree_cluser() must gather all inodes that are active in the
          * cache to mark them stale, if we hit this case we don't actually want