libxfs: rename buffer cache index variable b_bn

To stop external users from using b_bn as the disk address of the
buffer, rename it to b_rhash_key to indicate that it is the buffer
cache index, not the block number of the buffer. Code that needs the
disk address should use xfs_buf_daddr() to obtain it.

Inspired-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
[sandeen: moved the xfs_buf_daddr changes to prior patch]
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>

diff --git a/libxfs/libxfs_io.h b/libxfs/libxfs_io.h
index a4d0a913c8232ce5c2ca7284a3fa218cede3a2a6..8a42f500c2eeb0b6af873f148b27e8b6e01731a2 100644 (file)
--- a/libxfs/libxfs_io.h
+++ b/libxfs/libxfs_io.h
@@ -79,7 +79,7 @@ struct xfs_buf_ops {
 struct xfs_buf {
        struct cache_node       b_node;
        unsigned int            b_flags;
-       xfs_daddr_t             b_bn;
+       xfs_daddr_t             b_cache_key;    /* buffer cache index */
        unsigned int            b_length;
        struct xfs_buftarg      *b_target;
        pthread_mutex_t         b_lock;
@@ -122,7 +122,7 @@ static inline xfs_daddr_t xfs_buf_daddr(struct xfs_buf *bp)
 
 static inline void xfs_buf_set_daddr(struct xfs_buf *bp, xfs_daddr_t blkno)
 {
-       assert(bp->b_bn == XFS_BUF_DADDR_NULL);
+       assert(bp->b_cache_key == XFS_BUF_DADDR_NULL);
        bp->b_maps[0].bm_bn = blkno;
 }
 

diff --git a/libxfs/rdwr.c b/libxfs/rdwr.c
index f07fad6222746a33d79a40804bc85f2090c939d6..e26f725e181a7aefa5d7e19726f7dd0af75f2c96 100644 (file)
--- a/libxfs/rdwr.c
+++ b/libxfs/rdwr.c
@@ -205,7 +205,7 @@ libxfs_bcompare(struct cache_node *node, cache_key_t key)
        struct xfs_bufkey       *bkey = (struct xfs_bufkey *)key;
 
        if (bp->b_target->bt_bdev == bkey->buftarg->bt_bdev &&
-           bp->b_bn == bkey->blkno) {
+           bp->b_cache_key == bkey->blkno) {
                if (bp->b_length == bkey->bblen)
                        return CACHE_HIT;
 #ifdef IO_BCOMPARE_CHECK
@@ -230,7 +230,7 @@ __initbuf(struct xfs_buf *bp, struct xfs_buftarg *btp, xfs_daddr_t bno,
                unsigned int bytes)
 {
        bp->b_flags = 0;
-       bp->b_bn = bno;
+       bp->b_cache_key = bno;
        bp->b_length = BTOBB(bytes);
        bp->b_target = btp;
        bp->b_mount = btp->bt_mount;
@@ -256,7 +256,7 @@ __initbuf(struct xfs_buf *bp, struct xfs_buftarg *btp, xfs_daddr_t bno,
 
        if (bp->b_maps == &bp->__b_map) {
                bp->b_nmaps = 1;
-               bp->b_maps[0].bm_bn = bp->b_bn;
+               bp->b_maps[0].bm_bn = bno;
                bp->b_maps[0].bm_len = bp->b_length;
        }
 }
@@ -591,7 +591,7 @@ libxfs_readbufr(struct xfs_buftarg *btp, xfs_daddr_t blkno, struct xfs_buf *bp,
        error = __read_buf(fd, bp->b_addr, bytes, LIBXFS_BBTOOFF64(blkno), flags);
        if (!error &&
            bp->b_target->bt_bdev == btp->bt_bdev &&
-           bp->b_bn == blkno &&
+           bp->b_cache_key == blkno &&
            bp->b_length == len)
                bp->b_flags |= LIBXFS_B_UPTODATE;
        bp->b_error = error;