[ALSA] Make buffer size of proc text interface variable (7e4eeec8) · Commits · 戴 / test

include/sound/info.h

+3 −3

Original line number	Diff line number	Diff line
		@@ -27,9 +27,9 @@
		/* buffer for information */
		struct snd_info_buffer {
		char buffer; / pointer to begin of buffer */
		char curr; / current position in buffer */
		unsigned long size; /* current size */
		unsigned long len; /* total length of buffer */
		unsigned int curr; /* current position in buffer */
		unsigned int size; /* current size */
		unsigned int len; /* total length of buffer */
		int stop; /* stop flag */
		int error; /* error code */
		};

sound/core/info.c

+79 −70

Original line number	Diff line number	Diff line
		@@ -21,7 +21,6 @@

		#include <sound/driver.h>
		#include <linux/init.h>
		#include <linux/vmalloc.h>
		#include <linux/time.h>
		#include <linux/smp_lock.h>
		#include <linux/string.h>
		@@ -82,6 +81,24 @@ static int snd_info_version_init(void);
		static int snd_info_version_done(void);


		/* resize the proc r/w buffer */
		static int resize_info_buffer(struct snd_info_buffer *buffer,
		unsigned int nsize)
		{
		char *nbuf;

		nsize = PAGE_ALIGN(nsize);
		nbuf = kmalloc(nsize, GFP_KERNEL);
		if (! nbuf)
		return -ENOMEM;

		memcpy(nbuf, buffer->buffer, buffer->len);
		kfree(buffer->buffer);
		buffer->buffer = nbuf;
		buffer->len = nsize;
		return 0;
		}

		/**
		* snd_iprintf - printf on the procfs buffer
		* @buffer: the procfs buffer
		@@ -95,17 +112,25 @@ int snd_iprintf(struct snd_info_buffer buffer, char fmt,...)
		{
		va_list args;
		int len, res;
		int err = 0;

		if (buffer->stop \|\| buffer->error)
		return 0;
		len = buffer->len - buffer->size;
		va_start(args, fmt);
		res = vsnprintf(buffer->curr, len, fmt, args);
		va_end(args);
		if (res >= len) {
		buffer->stop = 1;
		return 0;
		for (;;) {
		res = vsnprintf(buffer->buffer + buffer->curr, len, fmt, args);
		if (res < len)
		break;
		err = resize_info_buffer(buffer, buffer->len + PAGE_SIZE);
		if (err < 0)
		break;
		len = buffer->len - buffer->size;
		}
		va_end(args);

		if (err < 0)
		return err;
		buffer->curr += res;
		buffer->size += res;
		return res;
		@@ -225,7 +250,7 @@ static ssize_t snd_info_entry_write(struct file file, const char __user buffer
		struct snd_info_private_data *data;
		struct snd_info_entry *entry;
		struct snd_info_buffer *buf;
		size_t size = 0;
		ssize_t size = 0;
		loff_t pos;

		data = file->private_data;
		@@ -241,14 +266,20 @@ static ssize_t snd_info_entry_write(struct file file, const char __user buffer
		buf = data->wbuffer;
		if (buf == NULL)
		return -EIO;
		if (pos >= buf->len)
		mutex_unlock(&entry->access);
		if (pos + count >= buf->len) {
		if (resize_info_buffer(buf, pos + count)) {
		mutex_unlock(&entry->access);
		return -ENOMEM;
		size = buf->len - pos;
		size = min(count, size);
		if (copy_from_user(buf->buffer + pos, buffer, size))
		}
		}
		if (copy_from_user(buf->buffer + pos, buffer, count)) {
		mutex_unlock(&entry->access);
		return -EFAULT;
		if ((long)buf->size < pos + size)
		buf->size = pos + size;
		}
		buf->size = pos + count;
		mutex_unlock(&entry->access);
		size = count;
		break;
		case SNDRV_INFO_CONTENT_DATA:
		if (entry->c.ops->write)
		@@ -283,18 +314,14 @@ static int snd_info_entry_open(struct inode inode, struct file file)
		}
		mode = file->f_flags & O_ACCMODE;
		if (mode == O_RDONLY \|\| mode == O_RDWR) {
		if ((entry->content == SNDRV_INFO_CONTENT_TEXT &&
		!entry->c.text.read_size) \|\|
		(entry->content == SNDRV_INFO_CONTENT_DATA &&
		if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
		entry->c.ops->read == NULL)) {
		err = -ENODEV;
		goto __error;
		}
		}
		if (mode == O_WRONLY \|\| mode == O_RDWR) {
		if ((entry->content == SNDRV_INFO_CONTENT_TEXT &&
		!entry->c.text.write_size) \|\|
		(entry->content == SNDRV_INFO_CONTENT_DATA &&
		if ((entry->content == SNDRV_INFO_CONTENT_DATA &&
		entry->c.ops->write == NULL)) {
		err = -ENODEV;
		goto __error;
		@@ -310,49 +337,23 @@ static int snd_info_entry_open(struct inode inode, struct file file)
		case SNDRV_INFO_CONTENT_TEXT:
		if (mode == O_RDONLY \|\| mode == O_RDWR) {
		buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
		if (buffer == NULL) {
		kfree(data);
		err = -ENOMEM;
		goto __error;
		}
		buffer->len = (entry->c.text.read_size +
		(PAGE_SIZE - 1)) & ~(PAGE_SIZE - 1);
		buffer->buffer = vmalloc(buffer->len);
		if (buffer->buffer == NULL) {
		kfree(buffer);
		kfree(data);
		err = -ENOMEM;
		goto __error;
		}
		buffer->curr = buffer->buffer;
		if (buffer == NULL)
		goto __nomem;
		data->rbuffer = buffer;
		buffer->len = PAGE_SIZE;
		buffer->buffer = kmalloc(buffer->len, GFP_KERNEL);
		if (buffer->buffer == NULL)
		goto __nomem;
		}
		if (mode == O_WRONLY \|\| mode == O_RDWR) {
		buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
		if (buffer == NULL) {
		if (mode == O_RDWR) {
		vfree(data->rbuffer->buffer);
		kfree(data->rbuffer);
		}
		kfree(data);
		err = -ENOMEM;
		goto __error;
		}
		buffer->len = (entry->c.text.write_size +
		(PAGE_SIZE - 1)) & ~(PAGE_SIZE - 1);
		buffer->buffer = vmalloc(buffer->len);
		if (buffer->buffer == NULL) {
		if (mode == O_RDWR) {
		vfree(data->rbuffer->buffer);
		kfree(data->rbuffer);
		}
		kfree(buffer);
		kfree(data);
		err = -ENOMEM;
		goto __error;
		}
		buffer->curr = buffer->buffer;
		if (buffer == NULL)
		goto __nomem;
		data->wbuffer = buffer;
		buffer->len = PAGE_SIZE;
		buffer->buffer = kmalloc(buffer->len, GFP_KERNEL);
		if (buffer->buffer == NULL)
		goto __nomem;
		}
		break;
		case SNDRV_INFO_CONTENT_DATA: /* data */
		@@ -377,6 +378,17 @@ static int snd_info_entry_open(struct inode inode, struct file file)
		}
		return 0;

		__nomem:
		if (data->rbuffer) {
		kfree(data->rbuffer->buffer);
		kfree(data->rbuffer);
		}
		if (data->wbuffer) {
		kfree(data->wbuffer->buffer);
		kfree(data->wbuffer);
		}
		kfree(data);
		err = -ENOMEM;
		__error:
		module_put(entry->module);
		__error1:
		@@ -395,11 +407,11 @@ static int snd_info_entry_release(struct inode inode, struct file file)
		entry = data->entry;
		switch (entry->content) {
		case SNDRV_INFO_CONTENT_TEXT:
		if (mode == O_RDONLY \|\| mode == O_RDWR) {
		vfree(data->rbuffer->buffer);
		if (data->rbuffer) {
		kfree(data->rbuffer->buffer);
		kfree(data->rbuffer);
		}
		if (mode == O_WRONLY \|\| mode == O_RDWR) {
		if (data->wbuffer) {
		if (entry->c.text.write) {
		entry->c.text.write(entry, data->wbuffer);
		if (data->wbuffer->error) {
		@@ -408,7 +420,7 @@ static int snd_info_entry_release(struct inode inode, struct file file)
		data->wbuffer->error);
		}
		}
		vfree(data->wbuffer->buffer);
		kfree(data->wbuffer->buffer);
		kfree(data->wbuffer);
		}
		break;
		@@ -668,25 +680,23 @@ int snd_info_get_line(struct snd_info_buffer buffer, char line, int len)
		if (len <= 0 \|\| buffer->stop \|\| buffer->error)
		return 1;
		while (--len > 0) {
		c = *buffer->curr++;
		c = buffer->buffer[buffer->curr++];
		if (c == '\n') {
		if ((buffer->curr - buffer->buffer) >= (long)buffer->size) {
		if (buffer->curr >= buffer->size)
		buffer->stop = 1;
		}
		break;
		}
		*line++ = c;
		if ((buffer->curr - buffer->buffer) >= (long)buffer->size) {
		if (buffer->curr >= buffer->size) {
		buffer->stop = 1;
		break;
		}
		}
		while (c != '\n' && !buffer->stop) {
		c = *buffer->curr++;
		if ((buffer->curr - buffer->buffer) >= (long)buffer->size) {
		c = buffer->buffer[buffer->curr++];
		if (buffer->curr >= buffer->size)
		buffer->stop = 1;
		}
		}
		*line = '\0';
		return 0;
		}
		@@ -978,7 +988,6 @@ static int __init snd_info_version_init(void)
		entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL);
		if (entry == NULL)
		return -ENOMEM;
		entry->c.text.read_size = 256;
		entry->c.text.read = snd_info_version_read;
		if (snd_info_register(entry) < 0) {
		snd_info_free_entry(entry);

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