Revert 1.166 (but keep the bufq_wait() interface change), for this is wrong

and the bufq pointer might be NULL at the time it is `saved'.

Found the hard way on sparc due to the limited kva, with all disk active
processes ending up sleeping on "buf_needva".

ok kettenis@ krw@

diff --git a/sys/kern/vfs_bio.c b/sys/kern/vfs_bio.c
index e773694..c7da914 100644 (file)
--- a/sys/kern/vfs_bio.c
+++ b/sys/kern/vfs_bio.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: vfs_bio.c,v 1.166 2015/01/09 05:04:22 tedu Exp $      */
+/*     $OpenBSD: vfs_bio.c,v 1.167 2015/01/18 14:01:54 miod Exp $      */
 /*     $NetBSD: vfs_bio.c,v 1.44 1996/06/11 11:15:36 pk Exp $  */
 
 /*
@@ -516,7 +516,6 @@ bwrite(struct buf *bp)
        int rv, async, wasdelayed, s;
        struct vnode *vp;
        struct mount *mp;
-       struct bufq *bq;
 
        vp = bp->b_vp;
        if (vp != NULL)
@@ -570,7 +569,6 @@ bwrite(struct buf *bp)
 
        /* Initiate disk write.  Make sure the appropriate party is charged. */
        bp->b_vp->v_numoutput++;
-       bq = bp->b_bq;
        splx(s);
        SET(bp->b_flags, B_WRITEINPROG);
        VOP_STRATEGY(bp);
@@ -580,8 +578,8 @@ bwrite(struct buf *bp)
         * the number of outstanding write bufs drops below the low
         * water mark.
         */
-       if (bq)
-               bufq_wait(bq);
+       if (bp->b_bq)
+               bufq_wait(bp->b_bq);
 
        if (async)
                return (0);