Author: kib
Date: Sat Jul 11 11:21:56 2015
New Revision: 285384
URL: https://svnweb.freebsd.org/changeset/base/285384
Log:
Do not allow creation of the dirty buffers for the dead buffer
objects, i.e. for buffer objects which vnode was reclaimed. Buffer
cache cannot write such buffers. Return the error and discard the
buffer immediately on write attempt.
BO_DIRTY now always set during vnode reclamation, since it is used not
only for the INVARIANTS checks. Do allow placement of the clean
buffers on dead bufobj list, otherwise filesystems cannot use bufcache
at all after the devvp reclaim.
Reported and tested by: trasz
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Modified:
head/sys/kern/vfs_bio.c
head/sys/kern/vfs_subr.c
Modified: head/sys/kern/vfs_bio.c
==============================================================================
--- head/sys/kern/vfs_bio.c Sat Jul 11 04:55:01 2015 (r285383)
+++ head/sys/kern/vfs_bio.c Sat Jul 11 11:21:56 2015 (r285384)
@@ -1205,6 +1205,12 @@ bufwrite(struct buf *bp)
int vp_md;
CTR3(KTR_BUF, "bufwrite(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags);
+ if ((bp->b_bufobj->bo_flag & BO_DEAD) != 0) {
+ bp->b_flags |= B_INVAL | B_RELBUF;
+ bp->b_flags &= ~B_CACHE;
+ brelse(bp);
+ return (ENXIO);
+ }
if (bp->b_flags & B_INVAL) {
brelse(bp);
return (0);
Modified: head/sys/kern/vfs_subr.c
==============================================================================
--- head/sys/kern/vfs_subr.c Sat Jul 11 04:55:01 2015 (r285383)
+++ head/sys/kern/vfs_subr.c Sat Jul 11 11:21:56 2015 (r285384)
@@ -1584,7 +1584,8 @@ buf_vlist_add(struct buf *bp, struct buf
int error;
ASSERT_BO_WLOCKED(bo);
- KASSERT((bo->bo_flag & BO_DEAD) == 0, ("dead bo %p", bo));
+ KASSERT((xflags & BX_VNDIRTY) == 0 || (bo->bo_flag & BO_DEAD) == 0,
+ ("dead bo %p", bo));
KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0,
("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags));
bp->b_xflags |= xflags;
@@ -2841,7 +2842,7 @@ vgonel(struct vnode *vp)
while (vinvalbuf(vp, 0, 0, 0) != 0)
;
}
-#ifdef INVARIANTS
+
BO_LOCK(&vp->v_bufobj);
KASSERT(TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd) &&
vp->v_bufobj.bo_dirty.bv_cnt == 0 &&
@@ -2850,7 +2851,6 @@ vgonel(struct vnode *vp)
("vp %p bufobj not invalidated", vp));
vp->v_bufobj.bo_flag |= BO_DEAD;
BO_UNLOCK(&vp->v_bufobj);
-#endif
/*
* Reclaim the vnode.
_______________________________________________
[email protected] mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-head
To unsubscribe, send any mail to "[email protected]"
