[src/trunk]: src/sys/dev struct buf::b_iodone is not called at splbio() any m...

[bouyer <bouyer%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/26d56373442f
branches:  trunk
changeset: 751068:26d56373442f
user:      bouyer <bouyer%NetBSD.org@localhost>
date:      Sat Jan 23 18:31:04 2010 +0000

description:
struct buf::b_iodone is not called at splbio() any more.
Make sure non-MPsafe iodone callbacks raise the SPL as appropriate.
Fix buffer corruption issue I noticed in dk(4), and probable similar
issues in vnd(4) and cgd(4).

diffstat:

 sys/dev/cgd.c        |  8 +++++---
 sys/dev/dkwedge/dk.c |  8 +++++---
 sys/dev/vnd.c        |  6 ++++--
 3 files changed, 14 insertions(+), 8 deletions(-)

diffs (123 lines):

diff -r 24b26ce49917 -r 26d56373442f sys/dev/cgd.c
--- a/sys/dev/cgd.c     Sat Jan 23 18:26:37 2010 +0000
+++ b/sys/dev/cgd.c     Sat Jan 23 18:31:04 2010 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: cgd.c,v 1.68 2010/01/20 19:00:47 dyoung Exp $ */
+/* $NetBSD: cgd.c,v 1.69 2010/01/23 18:31:04 bouyer Exp $ */
 
 /*-
  * Copyright (c) 2002 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: cgd.c,v 1.68 2010/01/20 19:00:47 dyoung Exp $");
+__KERNEL_RCSID(0, "$NetBSD: cgd.c,v 1.69 2010/01/23 18:31:04 bouyer Exp $");
 
 #include <sys/types.h>
 #include <sys/param.h>
@@ -411,13 +411,13 @@
        return 0;
 }
 
-/* expected to be called at splbio() */
 static void
 cgdiodone(struct buf *nbp)
 {
        struct  buf *obp = nbp->b_private;
        struct  cgd_softc *cs = getcgd_softc(obp->b_dev);
        struct  dk_softc *dksc = &cs->sc_dksc;
+       int s;
 
        KDASSERT(cs);
 
@@ -453,10 +453,12 @@
        obp->b_resid = 0;
        if (obp->b_error != 0)
                obp->b_resid = obp->b_bcount;
+       s = splbio();
        disk_unbusy(&dksc->sc_dkdev, obp->b_bcount - obp->b_resid,
            (obp->b_flags & B_READ));
        biodone(obp);
        dk_iodone(di, dksc);
+       splx(s);
 }
 
 /* XXX: we should probably put these into dksubr.c, mostly */
diff -r 24b26ce49917 -r 26d56373442f sys/dev/dkwedge/dk.c
--- a/sys/dev/dkwedge/dk.c      Sat Jan 23 18:26:37 2010 +0000
+++ b/sys/dev/dkwedge/dk.c      Sat Jan 23 18:31:04 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: dk.c,v 1.52 2009/12/27 01:37:17 jakllsch Exp $ */
+/*     $NetBSD: dk.c,v 1.53 2010/01/23 18:31:04 bouyer Exp $   */
 
 /*-
  * Copyright (c) 2004, 2005, 2006, 2007 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: dk.c,v 1.52 2009/12/27 01:37:17 jakllsch Exp $");
+__KERNEL_RCSID(0, "$NetBSD: dk.c,v 1.53 2010/01/23 18:31:04 bouyer Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_dkwedge.h"
@@ -1198,7 +1198,6 @@
  * dkiodone:
  *
  *     I/O to a wedge has completed; alert the top half.
- *     NOTE: Must be called at splbio()!
  */
 static void
 dkiodone(struct buf *bp)
@@ -1206,6 +1205,8 @@
        struct buf *obp = bp->b_private;
        struct dkwedge_softc *sc = dkwedge_lookup(obp->b_dev);
 
+       int s = splbio();
+
        if (bp->b_error != 0)
                obp->b_error = bp->b_error;
        obp->b_resid = bp->b_resid;
@@ -1223,6 +1224,7 @@
 
        /* Kick the queue in case there is more work we can do. */
        dkstart(sc);
+       splx(s);
 }
 
 /*
diff -r 24b26ce49917 -r 26d56373442f sys/dev/vnd.c
--- a/sys/dev/vnd.c     Sat Jan 23 18:26:37 2010 +0000
+++ b/sys/dev/vnd.c     Sat Jan 23 18:31:04 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: vnd.c,v 1.205 2009/12/06 16:33:18 dsl Exp $    */
+/*     $NetBSD: vnd.c,v 1.206 2010/01/23 18:31:04 bouyer Exp $ */
 
 /*-
  * Copyright (c) 1996, 1997, 1998, 2008 The NetBSD Foundation, Inc.
@@ -130,7 +130,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vnd.c,v 1.205 2009/12/06 16:33:18 dsl Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vnd.c,v 1.206 2010/01/23 18:31:04 bouyer Exp $");
 
 #if defined(_KERNEL_OPT)
 #include "fs_nfs.h"
@@ -874,6 +874,7 @@
        struct vndxfer *vnx = VND_BUFTOXFER(bp);
        struct vnd_softc *vnd = vnx->vx_vnd;
        struct buf *obp = bp->b_private;
+       int s = splbio();
 
        KASSERT(&vnx->vx_buf == bp);
        KASSERT(vnd->sc_active > 0);
@@ -889,6 +890,7 @@
        if (vnd->sc_active == 0) {
                wakeup(&vnd->sc_tab);
        }
+       splx(s);
        obp->b_error = bp->b_error;
        obp->b_resid = bp->b_resid;
        buf_destroy(bp);