xfs: kill xfs_read_buf()

xfs_read_buf() is effectively the same as xfs_trans_read_buf() when called
outside a transaction context. The error handling is slightly different in that
xfs_read_buf stales the errored buffer it gets back, but there is probably good
reason for xfs_trans_read_buf() for doing this.

Hence update xfs_trans_read_buf() to the same error handling as xfs_read_buf(),
and convert all the callers of xfs_read_buf() to use the former function. We can
then remove xfs_read_buf().

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

6 files changed, 11 insertions, 63 deletions

diff --git a/fs/xfs/xfs_attr.c b/fs/xfs/xfs_attr.c
index c8ef9a9c312b..ad85bed99de8 100644
--- a/fs/xfs/xfs_attr.c
+++ b/fs/xfs/xfs_attr.c
@@ -1987,8 +1987,8 @@ xfs_attr_rmtval_get(xfs_da_args_t *args)
                                (map[i].br_startblock != HOLESTARTBLOCK));
                         dblkno = XFS_FSB_TO_DADDR(mp, map[i].br_startblock);
                         blkcnt = XFS_FSB_TO_BB(mp, map[i].br_blockcount);
-                        error = xfs_read_buf(mp, mp->m_ddev_targp, dblkno,
-                                             blkcnt, XBF_DONT_BLOCK, &bp);
+                        error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp,
+                                                   dblkno, blkcnt, 0, &bp);
                         if (error)
                                 return(error);
 
diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c
index 874d39883dab..e9f5bc0eea92 100644
--- a/fs/xfs/xfs_fsops.c
+++ b/fs/xfs/xfs_fsops.c
@@ -402,7 +402,7 @@ xfs_growfs_data_private(
 
         /* update secondary superblocks. */
         for (agno = 1; agno < nagcount; agno++) {
-                error = xfs_read_buf(mp, mp->m_ddev_targp,
+                error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp,
                                   XFS_AGB_TO_DADDR(mp, agno, XFS_SB_BLOCK(mp)),
                                   XFS_FSS_TO_BB(mp, 1), 0, &bp);
                 if (error) {
diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index 0d9bdb6bace4..c8ee0fc49042 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -2539,14 +2539,11 @@ xlog_recover_dquot_pass2(
                 return XFS_ERROR(EIO);
         ASSERT(dq_f->qlf_len == 1);
 
-        error = xfs_read_buf(mp, mp->m_ddev_targp,
-                             dq_f->qlf_blkno,
-                             XFS_FSB_TO_BB(mp, dq_f->qlf_len),
-                             0, &bp);
-        if (error) {
-                xfs_buf_ioerror_alert(bp, "xlog_recover_do..(read#3)");
+        error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp, dq_f->qlf_blkno,
+                                   XFS_FSB_TO_BB(mp, dq_f->qlf_len), 0, &bp);
+        if (error)
                 return error;
-        }
+
         ASSERT(bp);
         ddq = (xfs_disk_dquot_t *)xfs_buf_offset(bp, dq_f->qlf_boffset);
 
diff --git a/fs/xfs/xfs_rw.c b/fs/xfs/xfs_rw.c
index 2ce97758f4c7..3c2488a11165 100644
--- a/fs/xfs/xfs_rw.c
+++ b/fs/xfs/xfs_rw.c
@@ -92,56 +92,6 @@ xfs_do_force_shutdown(
 }
 
 /*
- * This isn't an absolute requirement, but it is
- * just a good idea to call xfs_read_buf instead of
- * directly doing a read_buf call. For one, we shouldn't
- * be doing this disk read if we are in SHUTDOWN state anyway,
- * so this stops that from happening. Secondly, this does all
- * the error checking stuff and the brelse if appropriate for
- * the caller, so the code can be a little leaner.
- */
-
-int
-xfs_read_buf(
-        struct xfs_mount *mp,
-        xfs_buftarg_t    *target,
-        xfs_daddr_t      blkno,
-        int              len,
-        uint             flags,
-        xfs_buf_t        **bpp)
-{
-        xfs_buf_t        *bp;
-        int              error;
-
-        if (!flags)
-                flags = XBF_MAPPED;
-
-        bp = xfs_buf_read(target, blkno, len, flags);
-        if (!bp)
-                return XFS_ERROR(EIO);
-        error = bp->b_error;
-        if (!error && !XFS_FORCED_SHUTDOWN(mp)) {
-                *bpp = bp;
-        } else {
-                *bpp = NULL;
-                if (error) {
-                        xfs_buf_ioerror_alert(bp, __func__);
-                } else {
-                        error = XFS_ERROR(EIO);
-                }
-                if (bp) {
-                        XFS_BUF_UNDONE(bp);
-                        xfs_buf_stale(bp);
-                        /*
-                         * brelse clears B_ERROR and b_error
-                         */
-                        xfs_buf_relse(bp);
-                }
-        }
-        return (error);
-}
-
-/*
  * helper function to extract extent size hint from inode
  */
 xfs_extlen_t
diff --git a/fs/xfs/xfs_rw.h b/fs/xfs/xfs_rw.h
index bbdb9ad6a4ba..967b3a4b76ab 100644
--- a/fs/xfs/xfs_rw.h
+++ b/fs/xfs/xfs_rw.h
@@ -39,9 +39,6 @@ xfs_fsb_to_db(struct xfs_inode *ip, xfs_fsblock_t fsb)
 /*
  * Prototypes for functions in xfs_rw.c.
  */
-extern int xfs_read_buf(struct xfs_mount *mp, xfs_buftarg_t *btp,
-                        xfs_daddr_t blkno, int len, uint flags,
-                        struct xfs_buf **bpp);
 extern xfs_extlen_t xfs_get_extsz_hint(struct xfs_inode *ip);
 
 #endif /* __XFS_RW_H__ */
diff --git a/fs/xfs/xfs_trans_buf.c b/fs/xfs/xfs_trans_buf.c
index f9cb7ee04dae..5e4cf617e56c 100644
--- a/fs/xfs/xfs_trans_buf.c
+++ b/fs/xfs/xfs_trans_buf.c
@@ -274,6 +274,8 @@ xfs_trans_read_buf(
         xfs_buf_log_item_t      *bip;
         int                     error;
 
+        *bpp = NULL;
+
         if (flags == 0)
                 flags = XBF_MAPPED;
 
@@ -289,6 +291,8 @@ xfs_trans_read_buf(
                 if (bp->b_error) {
                         error = bp->b_error;
                         xfs_buf_ioerror_alert(bp, __func__);
+                        XFS_BUF_UNDONE(bp);
+                        xfs_buf_stale(bp);
                         xfs_buf_relse(bp);
                         return error;
                 }