Gigaset: permit module unload
Fix the initialization and reference counting of the Gigaset driver modules
so that they can be unloaded when they are not actually in use.
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Cc: Hansjoerg Lipp <hjlipp@web.de>
Cc: Greg KH <gregkh@suse.de>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/isdn/gigaset/bas-gigaset.c b/drivers/isdn/gigaset/bas-gigaset.c
index 7c90530..5255b5e 100644
--- a/drivers/isdn/gigaset/bas-gigaset.c
+++ b/drivers/isdn/gigaset/bas-gigaset.c
@@ -134,7 +134,6 @@
static struct gigaset_driver *driver = NULL;
-static struct cardstate *cardstate = NULL;
/* usb specific object needed to register this driver with the usb subsystem */
static struct usb_driver gigaset_usb_driver = {
@@ -2247,11 +2246,11 @@
__func__, le16_to_cpu(udev->descriptor.idVendor),
le16_to_cpu(udev->descriptor.idProduct));
- cs = gigaset_getunassignedcs(driver);
- if (!cs) {
- dev_err(&udev->dev, "no free cardstate\n");
+ /* allocate memory for our device state and intialize it */
+ cs = gigaset_initcs(driver, BAS_CHANNELS, 0, 0, cidmode,
+ GIGASET_MODULENAME);
+ if (!cs)
return -ENODEV;
- }
ucs = cs->hw.bas;
/* save off device structure ptrs for later use */
@@ -2320,7 +2319,7 @@
error:
freeurbs(cs);
usb_set_intfdata(interface, NULL);
- gigaset_unassign(cs);
+ gigaset_freecs(cs);
return -ENODEV;
}
@@ -2362,7 +2361,7 @@
ucs->interface = NULL;
ucs->udev = NULL;
cs->dev = NULL;
- gigaset_unassign(cs);
+ gigaset_freecs(cs);
}
/* gigaset_suspend
@@ -2501,12 +2500,6 @@
&gigops, THIS_MODULE)) == NULL)
goto error;
- /* allocate memory for our device state and intialize it */
- cardstate = gigaset_initcs(driver, BAS_CHANNELS, 0, 0, cidmode,
- GIGASET_MODULENAME);
- if (!cardstate)
- goto error;
-
/* register this driver with the USB subsystem */
result = usb_register(&gigaset_usb_driver);
if (result < 0) {
@@ -2518,9 +2511,7 @@
info(DRIVER_DESC);
return 0;
-error: if (cardstate)
- gigaset_freecs(cardstate);
- cardstate = NULL;
+error:
if (driver)
gigaset_freedriver(driver);
driver = NULL;
@@ -2532,43 +2523,50 @@
*/
static void __exit bas_gigaset_exit(void)
{
- struct bas_cardstate *ucs = cardstate->hw.bas;
+ struct bas_cardstate *ucs;
+ int i;
gigaset_blockdriver(driver); /* => probe will fail
* => no gigaset_start any more
*/
- gigaset_shutdown(cardstate);
- /* from now on, no isdn callback should be possible */
+ /* stop all connected devices */
+ for (i = 0; i < driver->minors; i++) {
+ if (gigaset_shutdown(driver->cs + i) < 0)
+ continue; /* no device */
+ /* from now on, no isdn callback should be possible */
- /* close all still open channels */
- if (ucs->basstate & BS_B1OPEN) {
- gig_dbg(DEBUG_INIT, "closing B1 channel");
- usb_control_msg(ucs->udev, usb_sndctrlpipe(ucs->udev, 0),
- HD_CLOSE_B1CHANNEL, OUT_VENDOR_REQ, 0, 0,
- NULL, 0, BAS_TIMEOUT);
+ /* close all still open channels */
+ ucs = driver->cs[i].hw.bas;
+ if (ucs->basstate & BS_B1OPEN) {
+ gig_dbg(DEBUG_INIT, "closing B1 channel");
+ usb_control_msg(ucs->udev,
+ usb_sndctrlpipe(ucs->udev, 0),
+ HD_CLOSE_B1CHANNEL, OUT_VENDOR_REQ,
+ 0, 0, NULL, 0, BAS_TIMEOUT);
+ }
+ if (ucs->basstate & BS_B2OPEN) {
+ gig_dbg(DEBUG_INIT, "closing B2 channel");
+ usb_control_msg(ucs->udev,
+ usb_sndctrlpipe(ucs->udev, 0),
+ HD_CLOSE_B2CHANNEL, OUT_VENDOR_REQ,
+ 0, 0, NULL, 0, BAS_TIMEOUT);
+ }
+ if (ucs->basstate & BS_ATOPEN) {
+ gig_dbg(DEBUG_INIT, "closing AT channel");
+ usb_control_msg(ucs->udev,
+ usb_sndctrlpipe(ucs->udev, 0),
+ HD_CLOSE_ATCHANNEL, OUT_VENDOR_REQ,
+ 0, 0, NULL, 0, BAS_TIMEOUT);
+ }
+ ucs->basstate = 0;
}
- if (ucs->basstate & BS_B2OPEN) {
- gig_dbg(DEBUG_INIT, "closing B2 channel");
- usb_control_msg(ucs->udev, usb_sndctrlpipe(ucs->udev, 0),
- HD_CLOSE_B2CHANNEL, OUT_VENDOR_REQ, 0, 0,
- NULL, 0, BAS_TIMEOUT);
- }
- if (ucs->basstate & BS_ATOPEN) {
- gig_dbg(DEBUG_INIT, "closing AT channel");
- usb_control_msg(ucs->udev, usb_sndctrlpipe(ucs->udev, 0),
- HD_CLOSE_ATCHANNEL, OUT_VENDOR_REQ, 0, 0,
- NULL, 0, BAS_TIMEOUT);
- }
- ucs->basstate = 0;
/* deregister this driver with the USB subsystem */
usb_deregister(&gigaset_usb_driver);
/* this will call the disconnect-callback */
/* from now on, no disconnect/probe callback should be running */
- gigaset_freecs(cardstate);
- cardstate = NULL;
gigaset_freedriver(driver);
driver = NULL;
}
diff --git a/drivers/isdn/gigaset/common.c b/drivers/isdn/gigaset/common.c
index f8f7d7e5..aacedec 100644
--- a/drivers/isdn/gigaset/common.c
+++ b/drivers/isdn/gigaset/common.c
@@ -31,7 +31,6 @@
/* driver state flags */
#define VALID_MINOR 0x01
#define VALID_ID 0x02
-#define ASSIGNED 0x04
void gigaset_dbg_buffer(enum debuglevel level, const unsigned char *msg,
size_t len, const unsigned char *buf)
@@ -178,7 +177,7 @@
unsigned long flags;
spin_lock_irqsave(&bcs->cs->lock, flags);
- if (bcs->use_count) {
+ if (bcs->use_count || !try_module_get(bcs->cs->driver->owner)) {
gig_dbg(DEBUG_ANY, "could not allocate channel %d",
bcs->channel);
spin_unlock_irqrestore(&bcs->cs->lock, flags);
@@ -203,6 +202,7 @@
}
--bcs->use_count;
bcs->busy = 0;
+ module_put(bcs->cs->driver->owner);
gig_dbg(DEBUG_ANY, "freed channel %d", bcs->channel);
spin_unlock_irqrestore(&bcs->cs->lock, flags);
}
@@ -356,31 +356,28 @@
{
unsigned long flags;
unsigned i;
+ struct cardstate *cs;
struct cardstate *ret = NULL;
spin_lock_irqsave(&drv->lock, flags);
+ if (drv->blocked)
+ goto exit;
for (i = 0; i < drv->minors; ++i) {
- if (!(drv->flags[i] & VALID_MINOR)) {
- if (try_module_get(drv->owner)) {
- drv->flags[i] = VALID_MINOR;
- ret = drv->cs + i;
- }
+ cs = drv->cs + i;
+ if (!(cs->flags & VALID_MINOR)) {
+ cs->flags = VALID_MINOR;
+ ret = cs;
break;
}
}
+exit:
spin_unlock_irqrestore(&drv->lock, flags);
return ret;
}
static void free_cs(struct cardstate *cs)
{
- unsigned long flags;
- struct gigaset_driver *drv = cs->driver;
- spin_lock_irqsave(&drv->lock, flags);
- if (drv->flags[cs->minor_index] & VALID_MINOR)
- module_put(drv->owner);
- drv->flags[cs->minor_index] = 0;
- spin_unlock_irqrestore(&drv->lock, flags);
+ cs->flags = 0;
}
static void make_valid(struct cardstate *cs, unsigned mask)
@@ -388,7 +385,7 @@
unsigned long flags;
struct gigaset_driver *drv = cs->driver;
spin_lock_irqsave(&drv->lock, flags);
- drv->flags[cs->minor_index] |= mask;
+ cs->flags |= mask;
spin_unlock_irqrestore(&drv->lock, flags);
}
@@ -397,7 +394,7 @@
unsigned long flags;
struct gigaset_driver *drv = cs->driver;
spin_lock_irqsave(&drv->lock, flags);
- drv->flags[cs->minor_index] &= ~mask;
+ cs->flags &= ~mask;
spin_unlock_irqrestore(&drv->lock, flags);
}
@@ -893,10 +890,17 @@
}
EXPORT_SYMBOL_GPL(gigaset_start);
-void gigaset_shutdown(struct cardstate *cs)
+/* gigaset_shutdown
+ * check if a device is associated to the cardstate structure and stop it
+ * return value: 0 if ok, -1 if no device was associated
+ */
+int gigaset_shutdown(struct cardstate *cs)
{
mutex_lock(&cs->mutex);
+ if (!(cs->flags & VALID_MINOR))
+ return -1;
+
cs->waiting = 1;
if (!gigaset_add_event(cs, &cs->at_state, EV_SHUTDOWN, NULL, 0, NULL)) {
@@ -913,6 +917,7 @@
exit:
mutex_unlock(&cs->mutex);
+ return 0;
}
EXPORT_SYMBOL_GPL(gigaset_shutdown);
@@ -954,13 +959,11 @@
list_for_each_entry(drv, &drivers, list) {
spin_lock(&drv->lock);
for (i = 0; i < drv->minors; ++i) {
- if (drv->flags[i] & VALID_ID) {
- cs = drv->cs + i;
- if (cs->myid == id)
- ret = cs;
- }
- if (ret)
+ cs = drv->cs + i;
+ if ((cs->flags & VALID_ID) && cs->myid == id) {
+ ret = cs;
break;
+ }
}
spin_unlock(&drv->lock);
if (ret)
@@ -983,10 +986,9 @@
spin_lock(&drv->lock);
for (i = 0; i < drv->minors; ++i) {
gig_dbg(DEBUG_DRIVER, " index %u", i);
- gig_dbg(DEBUG_DRIVER, " flags 0x%02x",
- drv->flags[i]);
cs = drv->cs + i;
gig_dbg(DEBUG_DRIVER, " cardstate %p", cs);
+ gig_dbg(DEBUG_DRIVER, " flags 0x%02x", cs->flags);
gig_dbg(DEBUG_DRIVER, " minor_index %u",
cs->minor_index);
gig_dbg(DEBUG_DRIVER, " driver %p", cs->driver);
@@ -1010,7 +1012,7 @@
continue;
index = minor - drv->minor;
spin_lock(&drv->lock);
- if (drv->flags[index] & VALID_MINOR)
+ if (drv->cs[index].flags & VALID_MINOR)
ret = drv->cs + index;
spin_unlock(&drv->lock);
if (ret)
@@ -1038,7 +1040,6 @@
gigaset_if_freedriver(drv);
kfree(drv->cs);
- kfree(drv->flags);
kfree(drv);
}
EXPORT_SYMBOL_GPL(gigaset_freedriver);
@@ -1080,12 +1081,8 @@
if (!drv->cs)
goto error;
- drv->flags = kmalloc(minors * sizeof *drv->flags, GFP_KERNEL);
- if (!drv->flags)
- goto error;
-
for (i = 0; i < minors; ++i) {
- drv->flags[i] = 0;
+ drv->cs[i].flags = 0;
drv->cs[i].driver = drv;
drv->cs[i].ops = drv->ops;
drv->cs[i].minor_index = i;
@@ -1106,53 +1103,9 @@
}
EXPORT_SYMBOL_GPL(gigaset_initdriver);
-/* For drivers without fixed assignment device<->cardstate (usb) */
-struct cardstate *gigaset_getunassignedcs(struct gigaset_driver *drv)
-{
- unsigned long flags;
- struct cardstate *cs = NULL;
- unsigned i;
-
- spin_lock_irqsave(&drv->lock, flags);
- if (drv->blocked)
- goto exit;
- for (i = 0; i < drv->minors; ++i) {
- if ((drv->flags[i] & VALID_MINOR) &&
- !(drv->flags[i] & ASSIGNED)) {
- drv->flags[i] |= ASSIGNED;
- cs = drv->cs + i;
- break;
- }
- }
-exit:
- spin_unlock_irqrestore(&drv->lock, flags);
- return cs;
-}
-EXPORT_SYMBOL_GPL(gigaset_getunassignedcs);
-
-void gigaset_unassign(struct cardstate *cs)
-{
- unsigned long flags;
- unsigned *minor_flags;
- struct gigaset_driver *drv;
-
- if (!cs)
- return;
- drv = cs->driver;
- spin_lock_irqsave(&drv->lock, flags);
- minor_flags = drv->flags + cs->minor_index;
- if (*minor_flags & VALID_MINOR)
- *minor_flags &= ~ASSIGNED;
- spin_unlock_irqrestore(&drv->lock, flags);
-}
-EXPORT_SYMBOL_GPL(gigaset_unassign);
-
void gigaset_blockdriver(struct gigaset_driver *drv)
{
- unsigned long flags;
- spin_lock_irqsave(&drv->lock, flags);
drv->blocked = 1;
- spin_unlock_irqrestore(&drv->lock, flags);
}
EXPORT_SYMBOL_GPL(gigaset_blockdriver);
diff --git a/drivers/isdn/gigaset/gigaset.h b/drivers/isdn/gigaset/gigaset.h
index 92986a5..f365993 100644
--- a/drivers/isdn/gigaset/gigaset.h
+++ b/drivers/isdn/gigaset/gigaset.h
@@ -435,6 +435,7 @@
unsigned minor_index;
struct device *dev;
struct device *tty_dev;
+ unsigned flags;
const struct gigaset_ops *ops;
@@ -539,7 +540,6 @@
unsigned minor;
unsigned minors;
struct cardstate *cs;
- unsigned *flags;
int blocked;
const struct gigaset_ops *ops;
@@ -767,10 +767,6 @@
void gigaset_debugdrivers(void);
struct cardstate *gigaset_get_cs_by_tty(struct tty_struct *tty);
struct cardstate *gigaset_get_cs_by_id(int id);
-
-/* For drivers without fixed assignment device<->cardstate (usb) */
-struct cardstate *gigaset_getunassignedcs(struct gigaset_driver *drv);
-void gigaset_unassign(struct cardstate *cs);
void gigaset_blockdriver(struct gigaset_driver *drv);
/* Allocate and initialize card state. Calls hardware dependent
@@ -789,7 +785,7 @@
void gigaset_stop(struct cardstate *cs);
/* Tell common.c that the driver is being unloaded. */
-void gigaset_shutdown(struct cardstate *cs);
+int gigaset_shutdown(struct cardstate *cs);
/* Tell common.c that an skb has been sent. */
void gigaset_skb_sent(struct bc_state *bcs, struct sk_buff *skb);
diff --git a/drivers/isdn/gigaset/interface.c b/drivers/isdn/gigaset/interface.c
index f4731c9..af195b0 100644
--- a/drivers/isdn/gigaset/interface.c
+++ b/drivers/isdn/gigaset/interface.c
@@ -161,7 +161,7 @@
tty->driver_data = NULL;
cs = gigaset_get_cs_by_tty(tty);
- if (!cs)
+ if (!cs || !try_module_get(cs->driver->owner))
return -ENODEV;
if (mutex_lock_interruptible(&cs->mutex))
@@ -207,6 +207,8 @@
}
mutex_unlock(&cs->mutex);
+
+ module_put(cs->driver->owner);
}
static int if_ioctl(struct tty_struct *tty, struct file *file,
diff --git a/drivers/isdn/gigaset/usb-gigaset.c b/drivers/isdn/gigaset/usb-gigaset.c
index c58ddee..77d20ab 100644
--- a/drivers/isdn/gigaset/usb-gigaset.c
+++ b/drivers/isdn/gigaset/usb-gigaset.c
@@ -115,7 +115,6 @@
static int gigaset_pre_reset(struct usb_interface *intf);
static struct gigaset_driver *driver = NULL;
-static struct cardstate *cardstate = NULL;
/* usb specific object needed to register this driver with the usb subsystem */
static struct usb_driver gigaset_usb_driver = {
@@ -727,11 +726,10 @@
dev_info(&udev->dev, "%s: Device matched ... !\n", __func__);
- cs = gigaset_getunassignedcs(driver);
- if (!cs) {
- dev_warn(&udev->dev, "no free cardstate\n");
+ /* allocate memory for our device state and intialize it */
+ cs = gigaset_initcs(driver, 1, 1, 0, cidmode, GIGASET_MODULENAME);
+ if (!cs)
return -ENODEV;
- }
ucs = cs->hw.usb;
/* save off device structure ptrs for later use */
@@ -818,7 +816,7 @@
usb_put_dev(ucs->udev);
ucs->udev = NULL;
ucs->interface = NULL;
- gigaset_unassign(cs);
+ gigaset_freecs(cs);
return retval;
}
@@ -852,7 +850,7 @@
ucs->interface = NULL;
ucs->udev = NULL;
cs->dev = NULL;
- gigaset_unassign(cs);
+ gigaset_freecs(cs);
}
/* gigaset_suspend
@@ -934,11 +932,6 @@
&ops, THIS_MODULE)) == NULL)
goto error;
- /* allocate memory for our device state and intialize it */
- cardstate = gigaset_initcs(driver, 1, 1, 0, cidmode, GIGASET_MODULENAME);
- if (!cardstate)
- goto error;
-
/* register this driver with the USB subsystem */
result = usb_register(&gigaset_usb_driver);
if (result < 0) {
@@ -951,9 +944,7 @@
info(DRIVER_DESC);
return 0;
-error: if (cardstate)
- gigaset_freecs(cardstate);
- cardstate = NULL;
+error:
if (driver)
gigaset_freedriver(driver);
driver = NULL;
@@ -967,11 +958,16 @@
*/
static void __exit usb_gigaset_exit(void)
{
+ int i;
+
gigaset_blockdriver(driver); /* => probe will fail
* => no gigaset_start any more
*/
- gigaset_shutdown(cardstate);
+ /* stop all connected devices */
+ for (i = 0; i < driver->minors; i++)
+ gigaset_shutdown(driver->cs + i);
+
/* from now on, no isdn callback should be possible */
/* deregister this driver with the USB subsystem */
@@ -979,8 +975,6 @@
/* this will call the disconnect-callback */
/* from now on, no disconnect/probe callback should be running */
- gigaset_freecs(cardstate);
- cardstate = NULL;
gigaset_freedriver(driver);
driver = NULL;
}