ISDN: Introduce .owner

The current way of passing a command to inc the module use count is
inherently racy, so expose a struct module *owner instead (which makes
it possible to fix this race, though that's not done yet).

Also, add some missing #include <linux/interrupt.h>

drivers/isdn/act2000/module.c

@@ -436,12 +436,6 @@ act2000_command(act2000_card * card, isdn_ctrl * c)
 				return -ENODEV;
 			printk(KERN_DEBUG "act2000 CMD_GETSIL not implemented\n");
 			return 0;
-		case ISDN_CMD_LOCK:
-			MOD_INC_USE_COUNT;
-			return 0;
-		case ISDN_CMD_UNLOCK:
-			MOD_DEC_USE_COUNT;
-			return 0;
         }
 	
         return -EINVAL;
@@ -620,6 +614,7 @@ act2000_alloccard(int bus, int port, int irq, char *id)
 	INIT_WORK(&card->rcv_tq, (void *) (void *) actcapi_dispatch, card);
 	INIT_WORK(&card->poll_tq, (void *) (void *) act2000_receive, card);
 	init_timer(&card->ptimer);
+	SET_MODULE_OWNER(&card->interface);
         card->interface.channels = ACT2000_BCH;
         card->interface.maxbufsize = 4000;
         card->interface.command = if_command;

drivers/isdn/capi/capidrv.c

@@ -1787,20 +1787,6 @@ static int capidrv_command(isdn_ctrl * c, capidrv_contr * card)
 		bchan->msn[0] = 0;
 		return 0;
 
-	case ISDN_CMD_LOCK:
-		if (debugmode > 1)
-			printk(KERN_DEBUG "capidrv-%d: ISDN_CMD_LOCK (%ld)\n", card->contrnr, c->arg);
-		MOD_INC_USE_COUNT;
-		break;
-
-	case ISDN_CMD_UNLOCK:
-		if (debugmode > 1)
-			printk(KERN_DEBUG "capidrv-%d: ISDN_CMD_UNLOCK (%ld)\n",
-					card->contrnr, c->arg);
-		MOD_DEC_USE_COUNT;
-		break;
-
-/* never called */
 	case ISDN_CMD_GETL2:
 		if (debugmode)
 			printk(KERN_DEBUG "capidrv-%d: ISDN_CMD_GETL2\n",

drivers/isdn/eicon/eicon_mod.c

@@ -569,12 +569,6 @@ eicon_command(eicon_card * card, isdn_ctrl * c)
 				return -ENODEV;
 			eicon_log(card, 1, "eicon CMD_GETSIL not implemented\n");
 			return 0;
-		case ISDN_CMD_LOCK:
-			MOD_INC_USE_COUNT;
-			return 0;
-		case ISDN_CMD_UNLOCK:
-			MOD_DEC_USE_COUNT;
-			return 0;
 #ifdef CONFIG_ISDN_TTY_FAX
 		case ISDN_CMD_FAXCMD:
 			if (!card->flags & EICON_FLAGS_RUNNING)
@@ -877,6 +871,7 @@ eicon_alloccard(int Type, int membase, int irq, char *id, int card_id)
 		tasklet_init(&card->snd_tq, eicon_transmit, (unsigned long)card);
 		tasklet_init(&card->rcv_tq, eicon_rcv_dispatch, (unsigned long)card);
 		tasklet_init(&card->ack_tq, eicon_ack_dispatch, (unsigned long)card);
+		SET_MODULE_OWNER(&card->interface);
 		card->interface.maxbufsize = 4000;
 		card->interface.command = if_command;
 		card->interface.writebuf_skb = if_sendbuf;

drivers/isdn/hardware/eicon/i4lididrv.c

@@ -629,12 +629,6 @@ eicon_command(eicon_card * card, isdn_ctrl * c)
 				return -ENODEV;
 			eicon_log(card, 1, "%s: CMD_GETSIL not implemented\n", DRIVERLNAME);
 			return 0;
-		case ISDN_CMD_LOCK:
-			MOD_INC_USE_COUNT;
-			return 0;
-		case ISDN_CMD_UNLOCK:
-			MOD_DEC_USE_COUNT;
-			return 0;
 #ifdef CONFIG_ISDN_TTY_FAX
 		case ISDN_CMD_FAXCMD:
 			if (!card->flags & EICON_FLAGS_RUNNING)
@@ -961,6 +955,7 @@ eicon_alloccard(DESCRIPTOR *d)
 	skb_queue_head_init(&card->sackq);
 	skb_queue_head_init(&card->statq);
 	card->statq_entries = 0;
+	SET_MODULE_OWNER(&card->interface);
 	card->interface.maxbufsize = 4000;
 	card->interface.command = if_command;
 	card->interface.writebuf_skb = if_sendbuf;

drivers/isdn/hisax/callc.c

@@ -29,8 +29,6 @@ const char *lli_revision = "$Revision: 2.51.6.6 $";
 
 extern struct IsdnCard cards[];
 extern int nrcards;
-extern void HiSax_mod_dec_use_count(struct IsdnCardState *cs);
-extern void HiSax_mod_inc_use_count(struct IsdnCardState *cs);
 
 static int init_b_st(struct Channel *chanp, int incoming);
 static void release_b_st(struct Channel *chanp);
@@ -1584,22 +1582,6 @@ HiSax_command(isdn_ctrl * ic)
 					break;
 			}
 			break;
-		case (ISDN_CMD_LOCK):
-			HiSax_mod_inc_use_count(csta);
-#ifdef MODULE
-			if (csta->channel[0].debug & 0x400)
-				HiSax_putstatus(csta, "   LOCK ", "modcnt %lx",
-					MOD_USE_COUNT);
-#endif				/* MODULE */
-			break;
-		case (ISDN_CMD_UNLOCK):
-			HiSax_mod_dec_use_count(csta);
-#ifdef MODULE
-			if (csta->channel[0].debug & 0x400)
-				HiSax_putstatus(csta, " UNLOCK ", "modcnt %lx",
-					MOD_USE_COUNT);
-#endif				/* MODULE */
-			break;
 		case (ISDN_CMD_IOCTL):
 			switch (ic->arg) {
 				case (0):

drivers/isdn/hisax/config.c

@@ -942,6 +942,7 @@ static int __devinit checkcard(int cardnr, char *id, int *busy_flag)
 	cs->status_write = cs->status_buf;
 	cs->status_end = cs->status_buf + HISAX_STATUS_BUFSIZE - 1;
 	cs->typ = card->typ;
+	SET_MODULE_OWNER(&cs->iif);
 	strcpy(cs->iif.id, id);
 	cs->iif.channels = 2;
 	cs->iif.maxbufsize = MAX_DATA_SIZE;
@@ -1769,6 +1770,7 @@ int hisax_register(struct hisax_d_if *hisax_d_if, struct hisax_b_if *b_if[],
 	hisax_d_if->cs = cs;
 	cs->hw.hisax_d_if = hisax_d_if;
 	cs->cardmsg = hisax_cardmsg;
+	cs->iif.owner = hisax_d_if->owner; // FIXME should be done before registering
 	INIT_WORK(&cs->work, hisax_bh, cs);
 	cs->channel[0].d_st->l1.l2l1 = hisax_d_l2l1;
 	for (i = 0; i < 2; i++) {
@@ -2053,33 +2055,6 @@ static void EChannel_proc_rcv(struct hisax_d_if *d_if)
 	}
 }
 
-void HiSax_mod_dec_use_count(struct IsdnCardState *cs)
-{
-	struct module *mod;
-
-	if (cs && cs->cardmsg == hisax_cardmsg) {
-		mod = cs->hw.hisax_d_if->owner;
-		if (mod)
-			__MOD_DEC_USE_COUNT(mod);
-	} else {
-		MOD_DEC_USE_COUNT;
-	}
-}
-
-void HiSax_mod_inc_use_count(struct IsdnCardState *cs)
-{
-	struct module *mod;
-
-	if (cs && cs->cardmsg == hisax_cardmsg) {
-		mod = cs->hw.hisax_d_if->owner;
-		if (mod)
-		// hope we do win the race...
-			try_inc_mod_count(mod);
-	} else {
-		MOD_INC_USE_COUNT;
-	}
-}
-
 #include <linux/pci.h>
 
 static struct pci_device_id hisax_pci_tbl[] __initdata = {

drivers/isdn/i4l/isdn_common.c

@@ -429,7 +429,6 @@ struct isdn_driver {
 	atomic_t            refcnt;
 	unsigned long       flags;            /* Misc driver Flags           */
 	unsigned long       features;
-	int                 locks;            /* Number of locks             */
 	int                 channels;         /* Number of channels          */
 	wait_queue_head_t   st_waitq;         /* Wait-Queue for status-reads */
 	int                 maxbufsize;       /* Maximum Buffersize supported*/
@@ -630,14 +629,6 @@ drv_stat_unload(struct fsm_inst *fi, int pr, void *arg)
 	spin_unlock_irqrestore(&drivers_lock, flags);
 	put_drv(drv);
 
-	while (drv->locks > 0) {
-		isdn_ctrl cmd;
-		cmd.driver = drv->di;
-		cmd.arg = 0;
-		cmd.command = ISDN_CMD_UNLOCK;
-		__drv_command(drv, &cmd);
-		drv->locks--;
-	}
 	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
 		if (slots[i].di == drv->di) {
  			slots[i].di = -1;
@@ -993,23 +984,14 @@ static int isdn_wildmat(char *s, char *p);
 static void
 isdn_lock_driver(struct isdn_driver *drv)
 {
-	isdn_ctrl cmd;
-
-	cmd.driver = drv->di;
-	cmd.arg = 0;
-	cmd.command = ISDN_CMD_LOCK;
-	__drv_command(drv, &cmd);
+	// FIXME don't ignore return value
+	try_module_get(drv->interface->owner);
 }
 
 static void
 isdn_unlock_driver(struct isdn_driver *drv)
 {
-	isdn_ctrl cmd;
-
-	cmd.driver = drv->di;
-	cmd.arg = 0;
-	cmd.command = ISDN_CMD_UNLOCK;
-	__drv_command(drv, &cmd);
+	module_put(drv->interface->owner);
 }
 
 #if defined(ISDN_DEBUG_NET_DUMP) || defined(ISDN_DEBUG_MODEM_DUMP)
@@ -1135,10 +1117,6 @@ __drv_command(struct isdn_driver *drv, isdn_ctrl *c)
 {
 #ifdef ISDN_DEBUG_COMMAND
 	switch (c->command) {
-	case ISDN_CMD_LOCK: 
-		printk(KERN_DEBUG "ISDN_CMD_LOCK %d/%ld\n", c->driver, c->arg & 0xff); break;
-	case ISDN_CMD_UNLOCK: 
-		printk(KERN_DEBUG "ISDN_CMD_UNLOCK %d/%ld\n", c->driver, c->arg & 0xff); break;
 	case ISDN_CMD_SETL2: 
 		printk(KERN_DEBUG "ISDN_CMD_SETL2 %d/%ld\n", c->driver, c->arg & 0xff); break;
 	case ISDN_CMD_SETL3: 

drivers/isdn/icn/icn.c

@@ -1471,12 +1471,6 @@ icn_command(isdn_ctrl * c, icn_card * card)
 			if (!card->flags & ICN_FLAGS_RUNNING)
 				return -ENODEV;
 			break;
-		case ISDN_CMD_LOCK:
-			MOD_INC_USE_COUNT;
-			break;
-		case ISDN_CMD_UNLOCK:
-			MOD_DEC_USE_COUNT;
-			break;
 		default:
 			return -EINVAL;
 	}
@@ -1577,6 +1571,7 @@ icn_initcard(int port, char *id)
 	}
 	memset((char *) card, 0, sizeof(icn_card));
 	card->port = port;
+	SET_MODULE_OWNER(&card->interface);
 	card->interface.hl_hdrlen = 1;
 	card->interface.channels = ICN_BCH;
 	card->interface.maxbufsize = 4000;

drivers/isdn/isdnloop/isdnloop.c

@@ -1375,12 +1375,6 @@ isdnloop_command(isdn_ctrl * c, isdnloop_card * card)
 				if (!card->flags & ISDNLOOP_FLAGS_RUNNING)
 					return -ENODEV;
 				break;
-		case ISDN_CMD_LOCK:
-				MOD_INC_USE_COUNT;
-				break;
-		case ISDN_CMD_UNLOCK:
-				MOD_DEC_USE_COUNT;
-				break;
 		default:
 				return -EINVAL;
 			}
@@ -1482,6 +1476,7 @@ isdnloop_initcard(char *id)
 		return (isdnloop_card *) 0;
 	}
 	memset((char *) card, 0, sizeof(isdnloop_card));
+	SET_MODULE_OWNER(&card->interface);
 	card->interface.channels = ISDNLOOP_BCH;
 	card->interface.hl_hdrlen  = 1; /* scratch area for storing ack flag*/ 
 	card->interface.maxbufsize = 4000;

drivers/isdn/pcbit/drv.c

@@ -171,9 +171,10 @@ int pcbit_init_dev(int board, int mem_base, int irq)
 
 	dev->dev_if = dev_if;
 
-	dev_if->channels = 2;
-
+	SET_MODULE_OWNER(dev_if);
 
+	dev_if->channels = 2;
+	
 	dev_if->features = (ISDN_FEATURE_P_EURO  | ISDN_FEATURE_L3_TRANS | 
 			    ISDN_FEATURE_L2_HDLC | ISDN_FEATURE_L2_TRANS );
 
@@ -279,12 +280,6 @@ int pcbit_command(isdn_ctrl* ctl)
 	case ISDN_CMD_GETL2:
 		return chan->proto;
 		break;
-	case ISDN_CMD_LOCK:
-		MOD_INC_USE_COUNT;
-		break;
-	case ISDN_CMD_UNLOCK:
-		MOD_DEC_USE_COUNT;
-		break;
 	case ISDN_CMD_CLREAZ:
 		pcbit_clear_msn(dev);
 		break;

drivers/isdn/sc/command.c

@@ -34,8 +34,6 @@ int setl2(int card, unsigned long arg);
 int getl2(int card, unsigned long arg);
 int setl3(int card, unsigned long arg);
 int getl3(int card, unsigned long arg);
-int lock(void);
-int unlock(void);
 int acceptb(int card, unsigned long channel);
 
 extern int cinst;
@@ -70,8 +68,8 @@ static char *commands[] = { "ISDN_CMD_IOCTL",
 			    "ISDN_CMD_GETL2",
 			    "ISDN_CMD_SETL3",
 			    "ISDN_CMD_GETL3",
-			    "ISDN_CMD_LOCK",
-			    "ISDN_CMD_UNLOCK",
+			    NULL,
+			    NULL,
 			    "ISDN_CMD_SUSPEND",
 			    "ISDN_CMD_RESUME" };
 
@@ -158,10 +156,6 @@ int command(isdn_ctrl *cmd)
 		return setl3(card, cmd->arg);
 	case ISDN_CMD_GETL3:
 		return getl3(card, cmd->arg);
-	case ISDN_CMD_LOCK:
-		return lock();
-	case ISDN_CMD_UNLOCK:
-		return unlock();
 	default:
 		return -EINVAL;
 	}
@@ -499,19 +493,6 @@ int getsil(int card, unsigned long arg, char *num)
 	return 0;
 }
 
-
-int lock()
-{
-	MOD_INC_USE_COUNT;
-	return 0;
-}
-
-int unlock()
-{
-	MOD_DEC_USE_COUNT;
-	return 0;
-}
-
 int reset(int card)
 {
 	unsigned long flags;

drivers/isdn/sc/init.c

@@ -6,6 +6,7 @@
 
 #include <linux/module.h>
 #include <linux/init.h>
+#include <linux/interrupt.h>
 #include "includes.h"
 #include "hardware.h"
 #include "card.h"
@@ -286,6 +287,7 @@ static int __init sc_init(void)
 		}
 		memset(interface, 0, sizeof(isdn_if));
 
+		SET_MODULE_OWNER(interface);
 		interface->hl_hdrlen = 0;
 		interface->channels = channels;
 		interface->maxbufsize = BUFFER_SIZE;

drivers/isdn/tpam/tpam_commands.c

@@ -95,12 +95,6 @@ int tpam_command(isdn_ctrl *c) {
 						  c->arg >> 8);
 		case ISDN_CMD_GETL2:
 			return tpam_command_getl2(card, c->arg);
-		case ISDN_CMD_LOCK:
-			MOD_INC_USE_COUNT;
-			return 0;
-		case ISDN_CMD_UNLOCK:
-			MOD_DEC_USE_COUNT;
-			return 0;
 		case ISDN_CMD_PROCEED:
 			return tpam_command_proceed(card, c->arg);
 		default:

drivers/isdn/tpam/tpam_main.c

@@ -14,6 +14,7 @@
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/sched.h>
+#include <linux/interrupt.h>
 
 #include <linux/init.h>
 #include <asm/io.h>
@@ -131,6 +132,7 @@ static int __devinit tpam_probe(struct pci_dev *dev, const struct pci_device_id
 	copy_to_pam_dword(card, (void *)0x01840070, 0x00000010);
 
 	/* fill the ISDN link layer structure */
+	SET_MODULE_OWNER(&card->interface);
 	card->interface.channels = TPAM_NBCHANNEL;
 	card->interface.maxbufsize = TPAM_MAXBUFSIZE;
 	card->interface.features = 

include/linux/isdnif.h

@@ -173,8 +173,6 @@ typedef struct
 #define ISDN_CMD_GETL2   11       /* Get B-Chan. Layer2-Parameter          */
 #define ISDN_CMD_SETL3   12       /* Set B-Chan. Layer3-Parameter          */
 #define ISDN_CMD_GETL3   13       /* Get B-Chan. Layer3-Parameter          */
-#define ISDN_CMD_LOCK    14       /* Signal usage by upper levels          */
-#define ISDN_CMD_UNLOCK  15       /* Release usage-lock                    */
 #define ISDN_CMD_SUSPEND 16       /* Suspend connection                    */
 #define ISDN_CMD_RESUME  17       /* Resume connection                     */
 #define ISDN_CMD_PROCEED 18       /* Proceed with call establishment       */
@@ -423,6 +421,8 @@ typedef struct {
  *
  */
 typedef struct {
+  struct module *owner;
+
   /* Number of channels supported by this driver
    */
   int channels;