[src/netbsd-3]: src/sys/dev Pull up following revision(s) (requested by chs i...

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

details:   https://anonhg.NetBSD.org/src/rev/f54640f0f390
branches:  netbsd-3
changeset: 577882:f54640f0f390
user:      tron <tron%NetBSD.org@localhost>
date:      Fri Mar 17 15:18:50 2006 +0000

description:
Pull up following revision(s) (requested by chs in ticket #1202):
        sys/dev/fssvar.h: revision 1.13 via patch
        sys/dev/fss.c: revision 1.23 via patch
use lockmgr() instead of bespoke code for mutual exclusion in fss_ioctl().
only take the lock when we actually need it (and particularly not for
unknown cmds that are just going to fail immediately).  fixes PR 33060.

diffstat:

 sys/dev/fss.c    |  29 ++++++++++-------------------
 sys/dev/fssvar.h |   4 ++--
 2 files changed, 12 insertions(+), 21 deletions(-)

diffs (120 lines):

diff -r ac96da161411 -r f54640f0f390 sys/dev/fss.c
--- a/sys/dev/fss.c     Fri Mar 10 13:29:41 2006 +0000
+++ b/sys/dev/fss.c     Fri Mar 17 15:18:50 2006 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: fss.c,v 1.13.2.2 2005/04/21 19:01:40 tron Exp $        */
+/*     $NetBSD: fss.c,v 1.13.2.3 2006/03/17 15:18:50 tron Exp $        */
 
 /*-
  * Copyright (c) 2003 The NetBSD Foundation, Inc.
@@ -43,7 +43,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: fss.c,v 1.13.2.2 2005/04/21 19:01:40 tron Exp $");
+__KERNEL_RCSID(0, "$NetBSD: fss.c,v 1.13.2.3 2006/03/17 15:18:50 tron Exp $");
 
 #include "fss.h"
 
@@ -165,6 +165,7 @@
                sc->sc_unit = i;
                sc->sc_bdev = NODEV;
                simple_lock_init(&sc->sc_slock);
+               lockinit(&sc->sc_lock, PRIBIO, "fsslock", 0, 0);
                bufq_alloc(&sc->sc_bufq, BUFQ_FCFS|BUFQ_SORT_RAWBLOCK);
        }
 }
@@ -265,7 +266,7 @@
 int
 fss_ioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
 {
-       int s, error;
+       int error;
        struct fss_softc *sc;
        struct fss_set *fss = (struct fss_set *)data;
        struct fss_get *fsg = (struct fss_get *)data;
@@ -273,37 +274,31 @@
        if ((sc = FSS_DEV_TO_SOFTC(dev)) == NULL)
                return ENODEV;
 
-       FSS_LOCK(sc, s);
-       while ((sc->sc_flags & FSS_EXCL) == FSS_EXCL) {
-               error = ltsleep(sc, PRIBIO|PCATCH, "fsslock", 0, &sc->sc_slock);
-               if (error) {
-                       FSS_UNLOCK(sc, s);
-                       return error;
-               }
-       }
-       sc->sc_flags |= FSS_EXCL;
-       FSS_UNLOCK(sc, s);
-
        switch (cmd) {
        case FSSIOCSET:
+               lockmgr(&sc->sc_lock, LK_EXCLUSIVE, NULL);
                if ((flag & FWRITE) == 0)
                        error = EPERM;
                else if ((sc->sc_flags & FSS_ACTIVE) != 0)
                        error = EBUSY;
                else
                        error = fss_create_snapshot(sc, fss, p);
+               lockmgr(&sc->sc_lock, LK_RELEASE, NULL);
                break;
 
        case FSSIOCCLR:
+               lockmgr(&sc->sc_lock, LK_EXCLUSIVE, NULL);
                if ((flag & FWRITE) == 0)
                        error = EPERM;
                else if ((sc->sc_flags & FSS_ACTIVE) == 0)
                        error = ENXIO;
                else
                        error = fss_delete_snapshot(sc, p);
+               lockmgr(&sc->sc_lock, LK_RELEASE, NULL);
                break;
 
        case FSSIOCGET:
+               lockmgr(&sc->sc_lock, LK_EXCLUSIVE, NULL);
                switch (sc->sc_flags & (FSS_PERSISTENT | FSS_ACTIVE)) {
                case FSS_ACTIVE:
                        memcpy(fsg->fsg_mount, sc->sc_mntname, MNAMELEN);
@@ -325,6 +320,7 @@
                        error = ENXIO;
                        break;
                }
+               lockmgr(&sc->sc_lock, LK_RELEASE, NULL);
                break;
 
        case FSSIOFSET:
@@ -342,11 +338,6 @@
                break;
        }
 
-       FSS_LOCK(sc, s);
-       sc->sc_flags &= ~FSS_EXCL;
-       FSS_UNLOCK(sc, s);
-       wakeup(sc);
-
        return error;
 }
 
diff -r ac96da161411 -r f54640f0f390 sys/dev/fssvar.h
--- a/sys/dev/fssvar.h  Fri Mar 10 13:29:41 2006 +0000
+++ b/sys/dev/fssvar.h  Fri Mar 17 15:18:50 2006 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: fssvar.h,v 1.8.2.1 2005/04/21 19:01:59 tron Exp $      */
+/*     $NetBSD: fssvar.h,v 1.8.2.2 2006/03/17 15:18:50 tron Exp $      */
 
 /*-
  * Copyright (c) 2003 The NetBSD Foundation, Inc.
@@ -144,11 +144,11 @@
 struct fss_softc {
        int             sc_unit;        /* Logical unit number */
        struct simplelock sc_slock;     /* Protect this softc */
+       struct lock     sc_lock;        /* Protect this softc */
        volatile int    sc_flags;       /* Flags */
 #define FSS_ACTIVE     0x01            /* Snapshot is active */
 #define FSS_ERROR      0x02            /* I/O error occurred */
 #define FSS_BS_THREAD  0x04            /* Kernel thread is running */
-#define FSS_EXCL       0x08            /* Exclusive access granted */
 #define FSS_BS_ALLOC   0x10            /* Allocate backing store */
 #define FSS_PERSISTENT 0x20            /* File system internal snapshot */
 #define FSS_CDEV_OPEN  0x40            /* character device open */