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 7c905305406b6f18ddfa1e9d7f403fa77873aa6d..5255b5e20e132021c46259eb0f44de8c3af3fb10 100644 (file)
--- a/drivers/isdn/gigaset/bas-gigaset.c
+++ b/drivers/isdn/gigaset/bas-gigaset.c
@@ -134,7 +134,6 @@ struct bas_cardstate {
 
 
 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 @@ static int gigaset_probe(struct usb_interface *interface,
                 __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 @@ allocerr:
 error:
        freeurbs(cs);
        usb_set_intfdata(interface, NULL);
-       gigaset_unassign(cs);
+       gigaset_freecs(cs);
        return -ENODEV;
 }
 
@@ -2362,7 +2361,7 @@ static void gigaset_disconnect(struct usb_interface *interface)
        ucs->interface = NULL;
        ucs->udev = NULL;
        cs->dev = NULL;
-       gigaset_unassign(cs);
+       gigaset_freecs(cs);
 }
 
 /* gigaset_suspend
@@ -2501,12 +2500,6 @@ static int __init bas_gigaset_init(void)
                                       &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 @@ static int __init bas_gigaset_init(void)
        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 @@ error:  if (cardstate)
  */
 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 */
-
-       /* 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);
-       }
-       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);
+       /* 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 */
+               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;
        }
-       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 f8f7d7e553bf1b7916ccbd207d1823ec4fef773b..aacedec4986fc7e98cc9f827b935274acc645a41 100644 (file)
--- a/drivers/isdn/gigaset/common.c
+++ b/drivers/isdn/gigaset/common.c
@@ -31,7 +31,6 @@ MODULE_PARM_DESC(debug, "debug level");
 /* 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 @@ int gigaset_get_channel(struct bc_state *bcs)
        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 @@ void gigaset_free_channel(struct bc_state *bcs)
        }
        --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 @@ static struct cardstate *alloc_cs(struct gigaset_driver *drv)
 {
        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 @@ static void make_valid(struct cardstate *cs, unsigned mask)
        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 @@ static void make_invalid(struct cardstate *cs, unsigned mask)
        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 @@ error:
 }
 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 @@ void gigaset_shutdown(struct cardstate *cs)
 
 exit:
        mutex_unlock(&cs->mutex);
+       return 0;
 }
 EXPORT_SYMBOL_GPL(gigaset_shutdown);
 
@@ -954,13 +959,11 @@ struct cardstate *gigaset_get_cs_by_id(int id)
        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 @@ void gigaset_debugdrivers(void)
                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 @@ static struct cardstate *gigaset_get_cs_by_minor(unsigned minor)
                        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 @@ void gigaset_freedriver(struct gigaset_driver *drv)
        gigaset_if_freedriver(drv);
 
        kfree(drv->cs);
-       kfree(drv->flags);
        kfree(drv);
 }
 EXPORT_SYMBOL_GPL(gigaset_freedriver);
@@ -1080,12 +1081,8 @@ struct gigaset_driver *gigaset_initdriver(unsigned minor, unsigned minors,
        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 @@ error:
 }
 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 92986a5d40550e5309046721501d16dbb29e0161..f365993161fcc6a2a8432e4d890c9ddef45b628a 100644 (file)
--- a/drivers/isdn/gigaset/gigaset.h
+++ b/drivers/isdn/gigaset/gigaset.h
@@ -435,6 +435,7 @@ struct cardstate {
        unsigned minor_index;
        struct device *dev;
        struct device *tty_dev;
+       unsigned flags;
 
        const struct gigaset_ops *ops;
 
@@ -539,7 +540,6 @@ struct gigaset_driver {
        unsigned minor;
        unsigned minors;
        struct cardstate *cs;
-       unsigned *flags;
        int blocked;
 
        const struct gigaset_ops *ops;
@@ -767,10 +767,6 @@ void gigaset_freedriver(struct gigaset_driver *drv);
 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 @@ int gigaset_start(struct cardstate *cs);
 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 f4731c9984f6941ce05cc4b88fbde6dc82ee98b7..af195b07c191b6b02b09c57548f6477334672a92 100644 (file)
--- a/drivers/isdn/gigaset/interface.c
+++ b/drivers/isdn/gigaset/interface.c
@@ -161,7 +161,7 @@ static int if_open(struct tty_struct *tty, struct file *filp)
        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 @@ static void if_close(struct tty_struct *tty, struct file *filp)
        }
 
        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 c58ddee68dea0604af121f52e0f593e780d2f232..77d20ab0cd4d422b31226c9093a08eedb22ad937 100644 (file)
--- a/drivers/isdn/gigaset/usb-gigaset.c
+++ b/drivers/isdn/gigaset/usb-gigaset.c
@@ -115,7 +115,6 @@ static int gigaset_resume(struct usb_interface *intf);
 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 @@ static int gigaset_probe(struct usb_interface *interface,
 
        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 @@ error:
        usb_put_dev(ucs->udev);
        ucs->udev = NULL;
        ucs->interface = NULL;
-       gigaset_unassign(cs);
+       gigaset_freecs(cs);
        return retval;
 }
 
@@ -852,7 +850,7 @@ static void gigaset_disconnect(struct usb_interface *interface)
        ucs->interface = NULL;
        ucs->udev = NULL;
        cs->dev = NULL;
-       gigaset_unassign(cs);
+       gigaset_freecs(cs);
 }
 
 /* gigaset_suspend
@@ -934,11 +932,6 @@ static int __init usb_gigaset_init(void)
                                       &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 @@ static int __init usb_gigaset_init(void)
        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 @@ error:    if (cardstate)
  */
 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 @@ static void __exit usb_gigaset_exit(void)
        /* 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;
 }