Fix fuse device and data free.

glk · Oct 14, 2011 · 68764d7 · 68764d7
1 parent efbb506
commit 68764d7
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Showing 4 changed files with 137 additions and 129 deletions.
diff --git a/fuse_module/fuse_device.c b/fuse_module/fuse_device.c
@@ -87,8 +87,8 @@ fuse_device_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
 
 	FUSE_LOCK();
 	if (fuse_get_devdata(dev)) {
+		fdata_trydestroy(fdata);
 		FUSE_UNLOCK();
-		fdata_destroy(fdata);
 		goto busy;
 	} else {
 		fdata->dataflags |= FSESS_OPENED;
@@ -108,48 +108,37 @@ static int
 fuse_device_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
 {
 	struct fuse_data *data;
+	struct fuse_ticket *tick;
 
-	FUSE_LOCK();
 	data = fuse_get_devdata(dev);
-	if (! data)
+	if (!data)
 		panic("no fuse data upon fuse device close");
 	KASSERT(data->dataflags | FSESS_OPENED,
 	        ("fuse device is already closed upon close"));
 	fdata_set_dead(data);
+
+	FUSE_LOCK();
         data->dataflags &= ~FSESS_OPENED;
-	fuse_lck_mtx_lock(data->aw_mtx);
 
+	fuse_lck_mtx_lock(data->aw_mtx);
 	/* wakup poll()ers */
 	selwakeuppri(&data->ks_rsel, PZERO + 1);
-
-	DEBUG("mntco %d\n", data->mntco);
-	if (data->mntco > 0) {
-		struct fuse_ticket *tick;
-
-		/* Don't let syscall handlers wait in vain */
-		while ((tick = fuse_aw_pop(data))) {
-			fuse_lck_mtx_lock(tick->tk_aw_mtx);
-			fticket_set_answered(tick);
-			tick->tk_aw_errno = ENOTCONN;
-			wakeup(tick);
-			fuse_lck_mtx_unlock(tick->tk_aw_mtx);
-			fuse_lck_mtx_unlock(data->aw_mtx);
-			FUSE_ASSERT_AW_DONE(tick);
-			fuse_ticket_drop(tick);
-			fuse_lck_mtx_lock(data->aw_mtx);
-		}
-		fuse_lck_mtx_unlock(data->aw_mtx);
-
-		FUSE_UNLOCK();
-		goto out;
+	/* Don't let syscall handlers wait in vain */
+	while ((tick = fuse_aw_pop(data))) {
+		fuse_lck_mtx_lock(tick->tk_aw_mtx);
+		fticket_set_answered(tick);
+		tick->tk_aw_errno = ENOTCONN;
+		wakeup(tick);
+		fuse_lck_mtx_unlock(tick->tk_aw_mtx);
+		FUSE_ASSERT_AW_DONE(tick);
+		fuse_ticket_drop(tick);
 	}
-	dev->si_drv1 = NULL;
 	fuse_lck_mtx_unlock(data->aw_mtx);
-	FUSE_UNLOCK();
 
-	fdata_destroy(data);
+	dev->si_drv1 = NULL;
+	fdata_trydestroy(data);
+	FUSE_UNLOCK();
 
-out:
 	DEBUG("%s: device closed by thread %d.\n", dev->si_name, td->td_tid);
 	return(0);
 }

diff --git a/fuse_module/fuse_ipc.c b/fuse_module/fuse_ipc.c
@@ -341,14 +341,11 @@ fdata_alloc(struct cdev *fdev, struct ucred *cred)
 
     data = malloc(sizeof(struct fuse_data), M_FUSEMSG, M_WAITOK | M_ZERO);
 
-    data->mpri = FM_NOMOUNTED;
     data->fdev = fdev;
-    data->dataflags = 0;
     mtx_init(&data->ms_mtx, "fuse message list mutex", NULL, MTX_DEF);
     STAILQ_INIT(&data->ms_head);
     mtx_init(&data->aw_mtx, "fuse answer list mutex", NULL, MTX_DEF);
     TAILQ_INIT(&data->aw_head);
-    data->ticketer = 0;
     data->daemoncred = crhold(cred);
     data->daemon_timeout = FUSE_DEFAULT_DAEMON_TIMEOUT;
 
@@ -360,9 +357,23 @@ fdata_alloc(struct cdev *fdev, struct ucred *cred)
 }
 
 void
-fdata_destroy(struct fuse_data *data)
+fdata_trydestroy(struct fuse_data *data)
 {
-    debug_printf("data=%p, destroy.mntco = %d\n", data, data->mntco);
+    DEBUG("data=%p data.mp=%p data.fdev=%p data.flags=%04x\n",
+	data, data->mp, data->fdev, data->dataflags);
+
+    if (data->mp != NULL) {
+        MPASS(data->mp->mnt_data == data);
+        return;
+    }
+
+    if (data->fdev->si_drv1 != NULL) {
+        MPASS(data->fdev->si_drv1 == data);
+        return;
+    }
+
+    DEBUG("destroy: data=%p\n", data);
+    MPASS((data->dataflags & FSESS_OPENED) == 0);
 
     /* Driving off stage all that stuff thrown at device... */
     mtx_destroy(&data->ms_mtx);
@@ -381,19 +392,18 @@ fdata_set_dead(struct fuse_data *data)
 {
     debug_printf("data=%p\n", data);
 
-    fuse_lck_mtx_lock(data->ms_mtx);
+    FUSE_LOCK();
     if (fdata_get_dead(data)) {
-        fuse_lck_mtx_unlock(data->ms_mtx);
+        FUSE_UNLOCK();
         return;
     }
 
+    fuse_lck_mtx_lock(data->ms_mtx);
     data->dataflags |= FSESS_DEAD;
     wakeup_one(data);
     selwakeuppri(&data->ks_rsel, PZERO + 1);
-    fuse_lck_mtx_unlock(data->ms_mtx);
-
-    FUSE_LOCK();
     wakeup(&data->ticketer);
+    fuse_lck_mtx_unlock(data->ms_mtx);
     FUSE_UNLOCK();
 }
 

diff --git a/fuse_module/fuse_ipc.h b/fuse_module/fuse_ipc.h
@@ -127,8 +127,6 @@ struct fuse_data {
     struct cdev               *fdev;
     struct mount              *mp;
     struct vnode              *vroot;
-    enum mountpri              mpri;
-    int                        mntco;
     struct ucred              *daemoncred;
     int                        dataflags;
 
@@ -179,15 +177,14 @@ static __inline__
 struct fuse_data *
 fuse_get_devdata(struct cdev *fdev)
 {
-	return (fdev->si_drv1);
+    return fdev->si_drv1;
 }
 
 static __inline__
 struct fuse_data *
 fuse_get_mpdata(struct mount *mp)
 {
-    struct fuse_data *data = mp->mnt_data;
-    return (data->mpri == FM_PRIMARY ? data : NULL);
+    return mp->mnt_data;
 }
 
 static __inline__
@@ -276,7 +273,7 @@ fuse_libabi_geq(struct fuse_data *data, uint32_t abi_maj, uint32_t abi_min)
 }
 
 struct fuse_data *fdata_alloc(struct cdev *dev, struct ucred *cred);
-void fdata_destroy(struct fuse_data *data);
+void fdata_trydestroy(struct fuse_data *data);
 void fdata_set_dead(struct fuse_data *data);
 
 static __inline__