libxfs: use uncached buffers for initial mkfs writes

Teach mkfs to use uncached buffers to write the start and end of the
data device, the initial superblock, and the end of the realtime device
instead of open-coding uncached buffers.  This means we can get rid of
libxfs_purgebuf since we handle the state from the start now.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>

diff --git a/libxfs/libxfs_io.h b/libxfs/libxfs_io.h
index 21afc99c1d45f293dd4d976d22de4c1b3d499da9..1d30039ab2dd49ae04260c8f166399a332ea0055 100644 (file)
--- a/libxfs/libxfs_io.h
+++ b/libxfs/libxfs_io.h
@@ -211,7 +211,6 @@ struct xfs_buf *libxfs_getsb(struct xfs_mount *mp);
 extern void    libxfs_bcache_purge(void);
 extern void    libxfs_bcache_free(void);
 extern void    libxfs_bcache_flush(void);
-extern void    libxfs_purgebuf(xfs_buf_t *);
 extern int     libxfs_bcache_overflowed(void);
 
 /* Buffer (Raw) Interfaces */

diff --git a/libxfs/rdwr.c b/libxfs/rdwr.c
index cc7db73b4500887a26f47edd8a0f10bdaaa3d71b..958f6c2c5d746d3c99a038470c599d612a5451c7 100644 (file)
--- a/libxfs/rdwr.c
+++ b/libxfs/rdwr.c
@@ -640,18 +640,6 @@ libxfs_buf_relse(
                libxfs_putbufr(bp);
 }
 
-void
-libxfs_purgebuf(xfs_buf_t *bp)
-{
-       struct xfs_bufkey key = {NULL};
-
-       key.buftarg = bp->b_target;
-       key.blkno = bp->b_bn;
-       key.bblen = bp->b_length;
-
-       cache_node_purge(libxfs_bcache, &key, (struct cache_node *)bp);
-}
-
 static struct cache_node *
 libxfs_balloc(cache_key_t key)
 {

diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c
index 6d1ba933094ad78709434acd4f472a8ed8107e76..d9675bf1e686dc118fc875a3f9c96b475e57dc01 100644 (file)
--- a/mkfs/xfs_mkfs.c
+++ b/mkfs/xfs_mkfs.c
@@ -3351,6 +3351,21 @@ finish_superblock_setup(
 
 }
 
+/* Prepare an uncached buffer, ready to write something out. */
+static inline struct xfs_buf *
+alloc_write_buf(
+       struct xfs_buftarg      *btp,
+       xfs_daddr_t             daddr,
+       int                     bblen)
+{
+       struct xfs_buf          *bp;
+
+       bp = libxfs_buf_get_uncached(btp, bblen, 0);
+       bp->b_bn = daddr;
+       bp->b_maps[0].bm_bn = daddr;
+       return bp;
+}
+
 /*
  * Sanitise the data and log devices and prepare them so libxfs can mount the
  * device successfully. Also check we can access the rt device if configured.
@@ -3399,11 +3414,10 @@ prepare_devices(
         * the end of the device.  (MD sb is ~64k from the end, take out a wider
         * swath to be sure)
         */
-       buf = libxfs_buf_get(mp->m_ddev_targp, (xi->dsize - whack_blks),
-                           whack_blks);
+       buf = alloc_write_buf(mp->m_ddev_targp, (xi->dsize - whack_blks),
+                       whack_blks);
        memset(buf->b_addr, 0, WHACK_SIZE);
        libxfs_writebuf(buf, 0);
-       libxfs_purgebuf(buf);
 
        /*
         * Now zero out the beginning of the device, to obliterate any old
@@ -3411,19 +3425,17 @@ prepare_devices(
         * swap (somewhere around the page size), jfs (32k),
         * ext[2,3] and reiserfs (64k) - and hopefully all else.
         */
-       buf = libxfs_buf_get(mp->m_ddev_targp, 0, whack_blks);
+       buf = alloc_write_buf(mp->m_ddev_targp, 0, whack_blks);
        memset(buf->b_addr, 0, WHACK_SIZE);
        libxfs_writebuf(buf, 0);
-       libxfs_purgebuf(buf);
 
        /* OK, now write the superblock... */
-       buf = libxfs_buf_get(mp->m_ddev_targp, XFS_SB_DADDR,
+       buf = alloc_write_buf(mp->m_ddev_targp, XFS_SB_DADDR,
                        XFS_FSS_TO_BB(mp, 1));
        buf->b_ops = &xfs_sb_buf_ops;
        memset(buf->b_addr, 0, cfg->sectorsize);
        libxfs_sb_to_disk(buf->b_addr, sbp);
        libxfs_writebuf(buf, 0);
-       libxfs_purgebuf(buf);
 
        /* ...and zero the log.... */
        lsunit = sbp->sb_logsunit;
@@ -3438,12 +3450,11 @@ prepare_devices(
 
        /* finally, check we can write the last block in the realtime area */
        if (mp->m_rtdev_targp->dev && cfg->rtblocks > 0) {
-               buf = libxfs_buf_get(mp->m_rtdev_targp,
-                                   XFS_FSB_TO_BB(mp, cfg->rtblocks - 1LL),
-                                   BTOBB(cfg->blocksize));
+               buf = alloc_write_buf(mp->m_rtdev_targp,
+                               XFS_FSB_TO_BB(mp, cfg->rtblocks - 1LL),
+                               BTOBB(cfg->blocksize));
                memset(buf->b_addr, 0, cfg->blocksize);
                libxfs_writebuf(buf, 0);
-               libxfs_purgebuf(buf);
        }
 
 }