Commit c560a679 authored by Takashi Iwai's avatar Takashi Iwai
Browse files

ALSA: core: Remove child proc file elements recursively 



This patch changes the way to manage the resource release of proc
files: namely, let snd_info_free_entry() freeing the whole children.

This makes it us possible to drop the snd_device_*() management.  Then
snd_card_proc_new() becomes merely a wrapper to
snd_info_create_card_entry().

Together with this change, now you need to call snd_info_free_entry()
for a proc entry created via snd_card_proc_new(), while it was freed
via snd_device_free() beforehand.

Acked-by: default avatarJaroslav Kysela <perex@perex.cz>
Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 886364f6

include/sound/info.h

+7 −2
Original line number Diff line number Diff line
@@ -24,6 +24,7 @@ 


#include <linux/poll.h>

#include <linux/seq_file.h>

#include <sound/core.h>



/* buffer for information */

struct snd_info_buffer {
@@ -146,8 +147,12 @@ void snd_info_card_id_change(struct snd_card *card); 
int snd_info_register(struct snd_info_entry *entry);



/* for card drivers */

int snd_card_proc_new(struct snd_card *card, const char *name,

		      struct snd_info_entry **entryp);

static inline int snd_card_proc_new(struct snd_card *card, const char *name,

				    struct snd_info_entry **entryp)

{

	*entryp = snd_info_create_card_entry(card, name, card->proc_root);

	return *entryp ? 0 : -ENOMEM;

}



static inline void snd_info_set_text_ops(struct snd_info_entry *entry, 

	void *private_data,

sound/core/info.c

+13 −66
Original line number Diff line number Diff line
@@ -760,92 +760,39 @@ EXPORT_SYMBOL(snd_info_create_card_entry); 


static void snd_info_disconnect(struct snd_info_entry *entry)

{

	struct list_head *p, *n;



	list_for_each_safe(p, n, &entry->children) {

		snd_info_disconnect(list_entry(p, struct snd_info_entry, list));

	}

	struct snd_info_entry *p, *n;



	if (!entry->p)

		return;

	list_for_each_entry_safe(p, n, &entry->children, list)

		snd_info_disconnect(p);

	list_del_init(&entry->list);

	proc_remove(entry->p);

	entry->p = NULL;

}



static int snd_info_dev_free_entry(struct snd_device *device)

{

	struct snd_info_entry *entry = device->device_data;

	snd_info_free_entry(entry);

	return 0;

}



static int snd_info_dev_register_entry(struct snd_device *device)

{

	struct snd_info_entry *entry = device->device_data;

	return snd_info_register(entry);

}



/**

 * snd_card_proc_new - create an info entry for the given card

 * @card: the card instance

 * @name: the file name

 * @entryp: the pointer to store the new info entry

 *

 * Creates a new info entry and assigns it to the given card.

 * Unlike snd_info_create_card_entry(), this function registers the

 * info entry as an ALSA device component, so that it can be

 * unregistered/released without explicit call.

 * Also, you don't have to register this entry via snd_info_register(),

 * since this will be registered by snd_card_register() automatically.

 *

 * The parent is assumed as card->proc_root.

 *

 * For releasing this entry, use snd_device_free() instead of

 * snd_info_free_entry(). 

 *

 * Return: Zero if successful, or a negative error code on failure.

 */

int snd_card_proc_new(struct snd_card *card, const char *name,

		      struct snd_info_entry **entryp)

{

	static struct snd_device_ops ops = {

		.dev_free = snd_info_dev_free_entry,

		.dev_register =	snd_info_dev_register_entry,

		/* disconnect is done via snd_info_card_disconnect() */

	};

	struct snd_info_entry *entry;

	int err;



	entry = snd_info_create_card_entry(card, name, card->proc_root);

	if (! entry)

		return -ENOMEM;

	if ((err = snd_device_new(card, SNDRV_DEV_INFO, entry, &ops)) < 0) {

		snd_info_free_entry(entry);

		return err;

	}

	if (entryp)

		*entryp = entry;

	return 0;

}



EXPORT_SYMBOL(snd_card_proc_new);



/**

 * snd_info_free_entry - release the info entry

 * @entry: the info entry

 *

 * Releases the info entry.  Don't call this after registered.

 * Releases the info entry.

 */

void snd_info_free_entry(struct snd_info_entry * entry)

{

	if (entry == NULL)

	struct snd_info_entry *p, *n;



	if (!entry)

		return;

	if (entry->p) {

		mutex_lock(&info_mutex);

		snd_info_disconnect(entry);

		mutex_unlock(&info_mutex);

	}



	/* free all children at first */

	list_for_each_entry_safe(p, n, &entry->children, list)

		snd_info_free_entry(p);



	kfree(entry->name);

	if (entry->private_free)

		entry->private_free(entry);

sound/pci/hda/patch_hdmi.c

+1 −1
Original line number Diff line number Diff line
@@ -592,7 +592,7 @@ static int eld_proc_new(struct hdmi_spec_per_pin *per_pin, int index) 
static void eld_proc_free(struct hdmi_spec_per_pin *per_pin)

{

	if (!per_pin->codec->bus->shutdown && per_pin->proc_entry) {

		snd_device_free(per_pin->codec->card, per_pin->proc_entry);

		snd_info_free_entry(per_pin->proc_entry);

		per_pin->proc_entry = NULL;

	}

}

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