xfs: simplify xfs_zero_remaining_bytes

xfs_zero_remaining_bytes() open codes a log of buffer manupulations
to do a read forllowed by a write. It can simply be replaced by an
uncached read followed by a xfs_bwrite() call.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index c53cc03..aa70620 100644 (file)
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -1122,14 +1122,6 @@ xfs_zero_remaining_bytes(
        if (endoff > XFS_ISIZE(ip))
                endoff = XFS_ISIZE(ip);
 
-       bp = xfs_buf_get_uncached(XFS_IS_REALTIME_INODE(ip) ?
-                                       mp->m_rtdev_targp : mp->m_ddev_targp,
-                                 BTOBB(mp->m_sb.sb_blocksize), 0);
-       if (!bp)
-               return -ENOMEM;
-
-       xfs_buf_unlock(bp);
-
        for (offset = startoff; offset <= endoff; offset = lastoffset + 1) {
                uint lock_mode;
 
@@ -1152,32 +1144,24 @@ xfs_zero_remaining_bytes(
                ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
                if (imap.br_state == XFS_EXT_UNWRITTEN)
                        continue;
-               XFS_BUF_UNDONE(bp);
-               XFS_BUF_UNWRITE(bp);
-               XFS_BUF_READ(bp);
-               XFS_BUF_SET_ADDR(bp, xfs_fsb_to_db(ip, imap.br_startblock));
 
-               error = xfs_buf_submit_wait(bp);
-               if (error) {
-                       xfs_buf_ioerror_alert(bp,
-                                       "xfs_zero_remaining_bytes(read)");
-                       break;
-               }
+               error = xfs_buf_read_uncached(XFS_IS_REALTIME_INODE(ip) ?
+                               mp->m_rtdev_targp : mp->m_ddev_targp,
+                               xfs_fsb_to_db(ip, imap.br_startblock),
+                               BTOBB(mp->m_sb.sb_blocksize),
+                               0, &bp, NULL);
+               if (error)
+                       return error;
+
                memset(bp->b_addr +
-                       (offset - XFS_FSB_TO_B(mp, imap.br_startoff)),
-                     0, lastoffset - offset + 1);
-               XFS_BUF_UNDONE(bp);
-               XFS_BUF_UNREAD(bp);
-               XFS_BUF_WRITE(bp);
+                               (offset - XFS_FSB_TO_B(mp, imap.br_startoff)),
+                      0, lastoffset - offset + 1);
 
-               error = xfs_buf_submit_wait(bp);
-               if (error) {
-                       xfs_buf_ioerror_alert(bp,
-                                       "xfs_zero_remaining_bytes(write)");
-                       break;
-               }
+               error = xfs_bwrite(bp);
+               xfs_buf_relse(bp);
+               if (error)
+                       return error;
        }
-       xfs_buf_free(bp);
        return error;
 }