[ALSA] dynamic minors (3/6): store device-specific object pointers dy…

…namically

Instead of storing the pointers to the device-specific structures in an
array, put them into the struct snd_minor, and look them up dynamically.

This makes the device type modules independent of the minor number
encoding.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

include/sound/core.h

@@ -187,6 +187,7 @@ struct snd_minor {
 	int card;			/* card number */
 	int device;			/* device number */
 	struct file_operations *f_ops;	/* file operations */
+	void *private_data;		/* private data for f_ops->open */
 	char name[0];			/* device name (keep at the end of
 								structure) */
 };
@@ -199,13 +200,17 @@ extern int snd_ecards_limit;
 void snd_request_card(int card);
 
 int snd_register_device(int type, struct snd_card *card, int dev,
-			struct file_operations *f_ops, const char *name);
+			struct file_operations *f_ops, void *private_data,
+			const char *name);
 int snd_unregister_device(int type, struct snd_card *card, int dev);
+void *snd_lookup_minor_data(unsigned int minor, int type);
 
 #ifdef CONFIG_SND_OSSEMUL
 int snd_register_oss_device(int type, struct snd_card *card, int dev,
-			    struct file_operations *f_ops, const char *name);
+			    struct file_operations *f_ops, void *private_data,
+			    const char *name);
 int snd_unregister_oss_device(int type, struct snd_card *card, int dev);
+void *snd_lookup_oss_minor_data(unsigned int minor, int type);
 #endif
 
 int snd_minor_info_init(void);

include/sound/hwdep.h

@@ -43,6 +43,7 @@ struct snd_hwdep_ops {
 
 struct snd_hwdep {
 	struct snd_card *card;
+	struct list_head list;
 	int device;
 	char id[32];
 	char name[80];

include/sound/pcm.h

@@ -412,6 +412,7 @@ struct snd_pcm_str {
 
 struct snd_pcm {
 	struct snd_card *card;
+	struct list_head list;
 	unsigned int device;	/* device number */
 	unsigned int info_flags;
 	unsigned short dev_class;
@@ -439,7 +440,6 @@ struct snd_pcm_notify {
  *  Registering
  */
 
-extern struct snd_pcm *snd_pcm_devices[];
 extern struct file_operations snd_pcm_f_ops[2];
 
 int snd_pcm_new(struct snd_card *card, char *id, int device,

include/sound/rawmidi.h

@@ -113,7 +113,7 @@ struct snd_rawmidi_str {
 
 struct snd_rawmidi {
 	struct snd_card *card;
-
+	struct list_head list;
 	unsigned int device;		/* device number */
 	unsigned int info_flags;	/* SNDRV_RAWMIDI_INFO_XXXX */
 	char id[64];
@@ -165,8 +165,8 @@ int snd_rawmidi_transmit(struct snd_rawmidi_substream *substream,
 /* main midi functions */
 
 int snd_rawmidi_info_select(struct snd_card *card, struct snd_rawmidi_info *info);
-int snd_rawmidi_kernel_open(int cardnum, int device, int subdevice, int mode,
-			    struct snd_rawmidi_file *rfile);
+int snd_rawmidi_kernel_open(struct snd_card *card, int device, int subdevice,
+			    int mode, struct snd_rawmidi_file *rfile);
 int snd_rawmidi_kernel_release(struct snd_rawmidi_file *rfile);
 int snd_rawmidi_output_params(struct snd_rawmidi_substream *substream,
 			      struct snd_rawmidi_params *params);

sound/core/control.c

@@ -47,13 +47,12 @@ static LIST_HEAD(snd_control_compat_ioctls);
 
 static int snd_ctl_open(struct inode *inode, struct file *file)
 {
-	int cardnum = SNDRV_MINOR_CARD(iminor(inode));
 	unsigned long flags;
 	struct snd_card *card;
 	struct snd_ctl_file *ctl;
 	int err;
 
-	card = snd_cards[cardnum];
+	card = snd_lookup_minor_data(iminor(inode), SNDRV_DEVICE_TYPE_CONTROL);
 	if (!card) {
 		err = -ENODEV;
 		goto __error1;
@@ -1277,8 +1276,8 @@ static int snd_ctl_dev_register(struct snd_device *device)
 	cardnum = card->number;
 	snd_assert(cardnum >= 0 && cardnum < SNDRV_CARDS, return -ENXIO);
 	sprintf(name, "controlC%i", cardnum);
-	if ((err = snd_register_device(SNDRV_DEVICE_TYPE_CONTROL,
-				       card, -1, &snd_ctl_f_ops, name)) < 0)
+	if ((err = snd_register_device(SNDRV_DEVICE_TYPE_CONTROL, card, -1,
+				       &snd_ctl_f_ops, card, name)) < 0)
 		return err;
 	return 0;
 }

sound/core/hwdep.c

@@ -35,18 +35,27 @@ MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>");
 MODULE_DESCRIPTION("Hardware dependent layer");
 MODULE_LICENSE("GPL");
 
-static struct snd_hwdep *snd_hwdep_devices[SNDRV_CARDS * SNDRV_MINOR_HWDEPS];
-
+static LIST_HEAD(snd_hwdep_devices);
 static DECLARE_MUTEX(register_mutex);
 
 static int snd_hwdep_free(struct snd_hwdep *hwdep);
 static int snd_hwdep_dev_free(struct snd_device *device);
 static int snd_hwdep_dev_register(struct snd_device *device);
 static int snd_hwdep_dev_unregister(struct snd_device *device);
 
-/*
 
- */
+static struct snd_hwdep *snd_hwdep_search(struct snd_card *card, int device)
+{
+	struct list_head *p;
+	struct snd_hwdep *hwdep;
+
+	list_for_each(p, &snd_hwdep_devices) {
+		hwdep = list_entry(p, struct snd_hwdep, list);
+		if (hwdep->card == card && hwdep->device == device)
+			return hwdep;
+	}
+	return NULL;
+}
 
 static loff_t snd_hwdep_llseek(struct file * file, loff_t offset, int orig)
 {
@@ -77,34 +86,25 @@ static ssize_t snd_hwdep_write(struct file * file, const char __user *buf,
 static int snd_hwdep_open(struct inode *inode, struct file * file)
 {
 	int major = imajor(inode);
-	int cardnum;
-	int device;
 	struct snd_hwdep *hw;
 	int err;
 	wait_queue_t wait;
 
 	if (major == snd_major) {
-		cardnum = SNDRV_MINOR_CARD(iminor(inode));
-		device = SNDRV_MINOR_DEVICE(iminor(inode)) - SNDRV_MINOR_HWDEP;
+		hw = snd_lookup_minor_data(iminor(inode),
+					   SNDRV_DEVICE_TYPE_HWDEP);
 #ifdef CONFIG_SND_OSSEMUL
 	} else if (major == SOUND_MAJOR) {
-		cardnum = SNDRV_MINOR_OSS_CARD(iminor(inode));
-		device = 0;
+		hw = snd_lookup_oss_minor_data(iminor(inode),
+					       SNDRV_OSS_DEVICE_TYPE_DMFM);
 #endif
 	} else
 		return -ENXIO;
-	cardnum %= SNDRV_CARDS;
-	device %= SNDRV_MINOR_HWDEPS;
-	hw = snd_hwdep_devices[(cardnum * SNDRV_MINOR_HWDEPS) + device];
 	if (hw == NULL)
 		return -ENODEV;
 
 	if (!hw->ops.open)
 		return -ENXIO;
-#ifdef CONFIG_SND_OSSEMUL
-	if (major == SOUND_MAJOR && hw->oss_type < 0)
-		return -ENXIO;
-#endif
 
 	if (!try_module_get(hw->card->module))
 		return -EFAULT;
@@ -265,42 +265,43 @@ static int snd_hwdep_control_ioctl(struct snd_card *card,
 				   struct snd_ctl_file * control,
 				   unsigned int cmd, unsigned long arg)
 {
-	unsigned int tmp;
-
-	tmp = card->number * SNDRV_MINOR_HWDEPS;
 	switch (cmd) {
 	case SNDRV_CTL_IOCTL_HWDEP_NEXT_DEVICE:
 		{
 			int device;
 
 			if (get_user(device, (int __user *)arg))
 				return -EFAULT;
+			down(&register_mutex);
 			device = device < 0 ? 0 : device + 1;
 			while (device < SNDRV_MINOR_HWDEPS) {
-				if (snd_hwdep_devices[tmp + device])
+				if (snd_hwdep_search(card, device))
 					break;
 				device++;
 			}
 			if (device >= SNDRV_MINOR_HWDEPS)
 				device = -1;
+			up(&register_mutex);
 			if (put_user(device, (int __user *)arg))
 				return -EFAULT;
 			return 0;
 		}
 	case SNDRV_CTL_IOCTL_HWDEP_INFO:
 		{
 			struct snd_hwdep_info __user *info = (struct snd_hwdep_info __user *)arg;
-			int device;
+			int device, err;
 			struct snd_hwdep *hwdep;
 
 			if (get_user(device, &info->device))
 				return -EFAULT;
-			if (device < 0 || device >= SNDRV_MINOR_HWDEPS)
-				return -ENXIO;
-			hwdep = snd_hwdep_devices[tmp + device];
-			if (hwdep == NULL)
-				return -ENXIO;
-			return snd_hwdep_info(hwdep, info);
+			down(&register_mutex);
+			hwdep = snd_hwdep_search(card, device);
+			if (hwdep)
+				err = snd_hwdep_info(hwdep, info);
+			else
+				err = -ENXIO;
+			up(&register_mutex);
+			return err;
 		}
 	}
 	return -ENOIOCTLCMD;
@@ -397,23 +398,22 @@ static int snd_hwdep_dev_free(struct snd_device *device)
 static int snd_hwdep_dev_register(struct snd_device *device)
 {
 	struct snd_hwdep *hwdep = device->device_data;
-	int idx, err;
+	int err;
 	char name[32];
 
 	down(&register_mutex);
-	idx = (hwdep->card->number * SNDRV_MINOR_HWDEPS) + hwdep->device;
-	if (snd_hwdep_devices[idx]) {
+	if (snd_hwdep_search(hwdep->card, hwdep->device)) {
 		up(&register_mutex);
 		return -EBUSY;
 	}
-	snd_hwdep_devices[idx] = hwdep;
+	list_add_tail(&hwdep->list, &snd_hwdep_devices);
 	sprintf(name, "hwC%iD%i", hwdep->card->number, hwdep->device);
 	if ((err = snd_register_device(SNDRV_DEVICE_TYPE_HWDEP,
 				       hwdep->card, hwdep->device,
-				       &snd_hwdep_f_ops, name)) < 0) {
+				       &snd_hwdep_f_ops, hwdep, name)) < 0) {
 		snd_printk(KERN_ERR "unable to register hardware dependent device %i:%i\n",
 			   hwdep->card->number, hwdep->device);
-		snd_hwdep_devices[idx] = NULL;
+		list_del(&hwdep->list);
 		up(&register_mutex);
 		return err;
 	}
@@ -425,7 +425,7 @@ static int snd_hwdep_dev_register(struct snd_device *device)
 		} else {
 			if (snd_register_oss_device(hwdep->oss_type,
 						    hwdep->card, hwdep->device,
-						    &snd_hwdep_f_ops,
+						    &snd_hwdep_f_ops, hwdep,
 						    hwdep->oss_dev) < 0) {
 				snd_printk(KERN_ERR "unable to register OSS compatibility device %i:%i\n",
 					   hwdep->card->number, hwdep->device);
@@ -441,12 +441,10 @@ static int snd_hwdep_dev_register(struct snd_device *device)
 static int snd_hwdep_dev_unregister(struct snd_device *device)
 {
 	struct snd_hwdep *hwdep = device->device_data;
-	int idx;
 
 	snd_assert(hwdep != NULL, return -ENXIO);
 	down(&register_mutex);
-	idx = (hwdep->card->number * SNDRV_MINOR_HWDEPS) + hwdep->device;
-	if (snd_hwdep_devices[idx] != hwdep) {
+	if (snd_hwdep_search(hwdep->card, hwdep->device) != hwdep) {
 		up(&register_mutex);
 		return -EINVAL;
 	}
@@ -455,7 +453,7 @@ static int snd_hwdep_dev_unregister(struct snd_device *device)
 		snd_unregister_oss_device(hwdep->oss_type, hwdep->card, hwdep->device);
 #endif
 	snd_unregister_device(SNDRV_DEVICE_TYPE_HWDEP, hwdep->card, hwdep->device);
-	snd_hwdep_devices[idx] = NULL;
+	list_del(&hwdep->list);
 	up(&register_mutex);
 	return snd_hwdep_free(hwdep);
 }
@@ -467,18 +465,14 @@ static int snd_hwdep_dev_unregister(struct snd_device *device)
 static void snd_hwdep_proc_read(struct snd_info_entry *entry,
 				struct snd_info_buffer *buffer)
 {
-	int idx;
+	struct list_head *p;
 	struct snd_hwdep *hwdep;
 
 	down(&register_mutex);
-	for (idx = 0; idx < SNDRV_CARDS * SNDRV_MINOR_HWDEPS; idx++) {
-		hwdep = snd_hwdep_devices[idx];
-		if (hwdep == NULL)
-			continue;
+	list_for_each(p, &snd_hwdep_devices) {
+		hwdep = list_entry(p, struct snd_hwdep, list);
 		snd_iprintf(buffer, "%02i-%02i: %s\n",
-					idx / SNDRV_MINOR_HWDEPS,
-					idx % SNDRV_MINOR_HWDEPS,
-					hwdep->name);
+			    hwdep->card->number, hwdep->device, hwdep->name);
 	}
 	up(&register_mutex);
 }
@@ -493,9 +487,8 @@ static int __init alsa_hwdep_init(void)
 {
 	struct snd_info_entry *entry;
 
-	memset(snd_hwdep_devices, 0, sizeof(snd_hwdep_devices));
 	if ((entry = snd_info_create_module_entry(THIS_MODULE, "hwdep", NULL)) != NULL) {
-		entry->c.text.read_size = 512;
+		entry->c.text.read_size = PAGE_SIZE;
 		entry->c.text.read = snd_hwdep_proc_read;
 		if (snd_info_register(entry) < 0) {
 			snd_info_free_entry(entry);

sound/core/oss/mixer_oss.c

@@ -41,12 +41,13 @@ MODULE_ALIAS_SNDRV_MINOR(SNDRV_MINOR_OSS_MIXER);
 
 static int snd_mixer_oss_open(struct inode *inode, struct file *file)
 {
-	int cardnum = SNDRV_MINOR_OSS_CARD(iminor(inode));
 	struct snd_card *card;
 	struct snd_mixer_oss_file *fmixer;
 	int err;
 
-	if ((card = snd_cards[cardnum]) == NULL)
+	card = snd_lookup_oss_minor_data(iminor(inode),
+					 SNDRV_OSS_DEVICE_TYPE_MIXER);
+	if (card == NULL)
 		return -ENODEV;
 	if (card->mixer_oss == NULL)
 		return -ENODEV;
@@ -1286,7 +1287,7 @@ static int snd_mixer_oss_notify_handler(struct snd_card *card, int cmd)
 		sprintf(name, "mixer%i%i", card->number, 0);
 		if ((err = snd_register_oss_device(SNDRV_OSS_DEVICE_TYPE_MIXER,
 						   card, 0,
-						   &snd_mixer_oss_f_ops,
+						   &snd_mixer_oss_f_ops, card,
 						   name)) < 0) {
 			snd_printk(KERN_ERR "unable to register OSS mixer device %i:%i\n",
 				   card->number, 0);

sound/core/oss/pcm_oss.c

@@ -1834,9 +1834,6 @@ static int snd_task_name(struct task_struct *task, char *name, size_t size)
 
 static int snd_pcm_oss_open(struct inode *inode, struct file *file)
 {
-	int minor = iminor(inode);
-	int cardnum = SNDRV_MINOR_OSS_CARD(minor);
-	int device;
 	int err;
 	char task_name[32];
 	struct snd_pcm *pcm;
@@ -1845,11 +1842,8 @@ static int snd_pcm_oss_open(struct inode *inode, struct file *file)
 	int nonblock;
 	wait_queue_t wait;
 
-	snd_assert(cardnum >= 0 && cardnum < SNDRV_CARDS, return -ENXIO);
-	device = SNDRV_MINOR_OSS_DEVICE(minor) == SNDRV_MINOR_OSS_PCM1 ?
-		adsp_map[cardnum] : dsp_map[cardnum];
-
-	pcm = snd_pcm_devices[(cardnum * SNDRV_PCM_DEVICES) + device];
+	pcm = snd_lookup_oss_minor_data(iminor(inode),
+					SNDRV_OSS_DEVICE_TYPE_PCM);
 	if (pcm == NULL) {
 		err = -ENODEV;
 		goto __error1;
@@ -1890,7 +1884,7 @@ static int snd_pcm_oss_open(struct inode *inode, struct file *file)
 	down(&pcm->open_mutex);
 	while (1) {
 		err = snd_pcm_oss_open_file(file, pcm, &pcm_oss_file,
-					    minor, psetup, csetup);
+					    iminor(inode), psetup, csetup);
 		if (err >= 0)
 			break;
 		if (err == -EAGAIN) {
@@ -2450,7 +2444,7 @@ static void register_oss_dsp(struct snd_pcm *pcm, int index)
 	sprintf(name, "dsp%i%i", pcm->card->number, pcm->device);
 	if (snd_register_oss_device(SNDRV_OSS_DEVICE_TYPE_PCM,
 				    pcm->card, index, &snd_pcm_oss_f_reg,
-				    name) < 0) {
+				    pcm, name) < 0) {
 		snd_printk(KERN_ERR "unable to register OSS PCM device %i:%i\n",
 			   pcm->card->number, pcm->device);
 	}