linux/sound/core/memalloc.c
Clemens Ladisch fea952e5cc ALSA: core: sparse cleanups
Change the core code where sparse complains.  In most cases, this means
just adding annotations to confirm that we indeed want to do the dirty
things we're doing.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-02-14 17:10:11 +01:00

547 lines
13 KiB
C

/*
* Copyright (c) by Jaroslav Kysela <perex@perex.cz>
* Takashi Iwai <tiwai@suse.de>
*
* Generic memory allocators
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/seq_file.h>
#include <asm/uaccess.h>
#include <linux/dma-mapping.h>
#include <linux/moduleparam.h>
#include <linux/mutex.h>
#include <sound/memalloc.h>
MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>, Jaroslav Kysela <perex@perex.cz>");
MODULE_DESCRIPTION("Memory allocator for ALSA system.");
MODULE_LICENSE("GPL");
/*
*/
static DEFINE_MUTEX(list_mutex);
static LIST_HEAD(mem_list_head);
/* buffer preservation list */
struct snd_mem_list {
struct snd_dma_buffer buffer;
unsigned int id;
struct list_head list;
};
/* id for pre-allocated buffers */
#define SNDRV_DMA_DEVICE_UNUSED (unsigned int)-1
/*
*
* Generic memory allocators
*
*/
static long snd_allocated_pages; /* holding the number of allocated pages */
static inline void inc_snd_pages(int order)
{
snd_allocated_pages += 1 << order;
}
static inline void dec_snd_pages(int order)
{
snd_allocated_pages -= 1 << order;
}
/**
* snd_malloc_pages - allocate pages with the given size
* @size: the size to allocate in bytes
* @gfp_flags: the allocation conditions, GFP_XXX
*
* Allocates the physically contiguous pages with the given size.
*
* Returns the pointer of the buffer, or NULL if no enoguh memory.
*/
void *snd_malloc_pages(size_t size, gfp_t gfp_flags)
{
int pg;
void *res;
if (WARN_ON(!size))
return NULL;
if (WARN_ON(!gfp_flags))
return NULL;
gfp_flags |= __GFP_COMP; /* compound page lets parts be mapped */
pg = get_order(size);
if ((res = (void *) __get_free_pages(gfp_flags, pg)) != NULL)
inc_snd_pages(pg);
return res;
}
/**
* snd_free_pages - release the pages
* @ptr: the buffer pointer to release
* @size: the allocated buffer size
*
* Releases the buffer allocated via snd_malloc_pages().
*/
void snd_free_pages(void *ptr, size_t size)
{
int pg;
if (ptr == NULL)
return;
pg = get_order(size);
dec_snd_pages(pg);
free_pages((unsigned long) ptr, pg);
}
/*
*
* Bus-specific memory allocators
*
*/
#ifdef CONFIG_HAS_DMA
/* allocate the coherent DMA pages */
static void *snd_malloc_dev_pages(struct device *dev, size_t size, dma_addr_t *dma)
{
int pg;
void *res;
gfp_t gfp_flags;
if (WARN_ON(!dma))
return NULL;
pg = get_order(size);
gfp_flags = GFP_KERNEL
| __GFP_COMP /* compound page lets parts be mapped */
| __GFP_NORETRY /* don't trigger OOM-killer */
| __GFP_NOWARN; /* no stack trace print - this call is non-critical */
res = dma_alloc_coherent(dev, PAGE_SIZE << pg, dma, gfp_flags);
if (res != NULL)
inc_snd_pages(pg);
return res;
}
/* free the coherent DMA pages */
static void snd_free_dev_pages(struct device *dev, size_t size, void *ptr,
dma_addr_t dma)
{
int pg;
if (ptr == NULL)
return;
pg = get_order(size);
dec_snd_pages(pg);
dma_free_coherent(dev, PAGE_SIZE << pg, ptr, dma);
}
#endif /* CONFIG_HAS_DMA */
/*
*
* ALSA generic memory management
*
*/
/**
* snd_dma_alloc_pages - allocate the buffer area according to the given type
* @type: the DMA buffer type
* @device: the device pointer
* @size: the buffer size to allocate
* @dmab: buffer allocation record to store the allocated data
*
* Calls the memory-allocator function for the corresponding
* buffer type.
*
* Returns zero if the buffer with the given size is allocated successfuly,
* other a negative value at error.
*/
int snd_dma_alloc_pages(int type, struct device *device, size_t size,
struct snd_dma_buffer *dmab)
{
if (WARN_ON(!size))
return -ENXIO;
if (WARN_ON(!dmab))
return -ENXIO;
dmab->dev.type = type;
dmab->dev.dev = device;
dmab->bytes = 0;
switch (type) {
case SNDRV_DMA_TYPE_CONTINUOUS:
dmab->area = snd_malloc_pages(size,
(__force gfp_t)(unsigned long)device);
dmab->addr = 0;
break;
#ifdef CONFIG_HAS_DMA
case SNDRV_DMA_TYPE_DEV:
dmab->area = snd_malloc_dev_pages(device, size, &dmab->addr);
break;
#endif
#ifdef CONFIG_SND_DMA_SGBUF
case SNDRV_DMA_TYPE_DEV_SG:
snd_malloc_sgbuf_pages(device, size, dmab, NULL);
break;
#endif
default:
printk(KERN_ERR "snd-malloc: invalid device type %d\n", type);
dmab->area = NULL;
dmab->addr = 0;
return -ENXIO;
}
if (! dmab->area)
return -ENOMEM;
dmab->bytes = size;
return 0;
}
/**
* snd_dma_alloc_pages_fallback - allocate the buffer area according to the given type with fallback
* @type: the DMA buffer type
* @device: the device pointer
* @size: the buffer size to allocate
* @dmab: buffer allocation record to store the allocated data
*
* Calls the memory-allocator function for the corresponding
* buffer type. When no space is left, this function reduces the size and
* tries to allocate again. The size actually allocated is stored in
* res_size argument.
*
* Returns zero if the buffer with the given size is allocated successfuly,
* other a negative value at error.
*/
int snd_dma_alloc_pages_fallback(int type, struct device *device, size_t size,
struct snd_dma_buffer *dmab)
{
int err;
while ((err = snd_dma_alloc_pages(type, device, size, dmab)) < 0) {
size_t aligned_size;
if (err != -ENOMEM)
return err;
if (size <= PAGE_SIZE)
return -ENOMEM;
aligned_size = PAGE_SIZE << get_order(size);
if (size != aligned_size)
size = aligned_size;
else
size >>= 1;
}
if (! dmab->area)
return -ENOMEM;
return 0;
}
/**
* snd_dma_free_pages - release the allocated buffer
* @dmab: the buffer allocation record to release
*
* Releases the allocated buffer via snd_dma_alloc_pages().
*/
void snd_dma_free_pages(struct snd_dma_buffer *dmab)
{
switch (dmab->dev.type) {
case SNDRV_DMA_TYPE_CONTINUOUS:
snd_free_pages(dmab->area, dmab->bytes);
break;
#ifdef CONFIG_HAS_DMA
case SNDRV_DMA_TYPE_DEV:
snd_free_dev_pages(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);
break;
#endif
#ifdef CONFIG_SND_DMA_SGBUF
case SNDRV_DMA_TYPE_DEV_SG:
snd_free_sgbuf_pages(dmab);
break;
#endif
default:
printk(KERN_ERR "snd-malloc: invalid device type %d\n", dmab->dev.type);
}
}
/**
* snd_dma_get_reserved - get the reserved buffer for the given device
* @dmab: the buffer allocation record to store
* @id: the buffer id
*
* Looks for the reserved-buffer list and re-uses if the same buffer
* is found in the list. When the buffer is found, it's removed from the free list.
*
* Returns the size of buffer if the buffer is found, or zero if not found.
*/
size_t snd_dma_get_reserved_buf(struct snd_dma_buffer *dmab, unsigned int id)
{
struct snd_mem_list *mem;
if (WARN_ON(!dmab))
return 0;
mutex_lock(&list_mutex);
list_for_each_entry(mem, &mem_list_head, list) {
if (mem->id == id &&
(mem->buffer.dev.dev == NULL || dmab->dev.dev == NULL ||
! memcmp(&mem->buffer.dev, &dmab->dev, sizeof(dmab->dev)))) {
struct device *dev = dmab->dev.dev;
list_del(&mem->list);
*dmab = mem->buffer;
if (dmab->dev.dev == NULL)
dmab->dev.dev = dev;
kfree(mem);
mutex_unlock(&list_mutex);
return dmab->bytes;
}
}
mutex_unlock(&list_mutex);
return 0;
}
/**
* snd_dma_reserve_buf - reserve the buffer
* @dmab: the buffer to reserve
* @id: the buffer id
*
* Reserves the given buffer as a reserved buffer.
*
* Returns zero if successful, or a negative code at error.
*/
int snd_dma_reserve_buf(struct snd_dma_buffer *dmab, unsigned int id)
{
struct snd_mem_list *mem;
if (WARN_ON(!dmab))
return -EINVAL;
mem = kmalloc(sizeof(*mem), GFP_KERNEL);
if (! mem)
return -ENOMEM;
mutex_lock(&list_mutex);
mem->buffer = *dmab;
mem->id = id;
list_add_tail(&mem->list, &mem_list_head);
mutex_unlock(&list_mutex);
return 0;
}
/*
* purge all reserved buffers
*/
static void free_all_reserved_pages(void)
{
struct list_head *p;
struct snd_mem_list *mem;
mutex_lock(&list_mutex);
while (! list_empty(&mem_list_head)) {
p = mem_list_head.next;
mem = list_entry(p, struct snd_mem_list, list);
list_del(p);
snd_dma_free_pages(&mem->buffer);
kfree(mem);
}
mutex_unlock(&list_mutex);
}
#ifdef CONFIG_PROC_FS
/*
* proc file interface
*/
#define SND_MEM_PROC_FILE "driver/snd-page-alloc"
static struct proc_dir_entry *snd_mem_proc;
static int snd_mem_proc_read(struct seq_file *seq, void *offset)
{
long pages = snd_allocated_pages >> (PAGE_SHIFT-12);
struct snd_mem_list *mem;
int devno;
static char *types[] = { "UNKNOWN", "CONT", "DEV", "DEV-SG" };
mutex_lock(&list_mutex);
seq_printf(seq, "pages : %li bytes (%li pages per %likB)\n",
pages * PAGE_SIZE, pages, PAGE_SIZE / 1024);
devno = 0;
list_for_each_entry(mem, &mem_list_head, list) {
devno++;
seq_printf(seq, "buffer %d : ID %08x : type %s\n",
devno, mem->id, types[mem->buffer.dev.type]);
seq_printf(seq, " addr = 0x%lx, size = %d bytes\n",
(unsigned long)mem->buffer.addr,
(int)mem->buffer.bytes);
}
mutex_unlock(&list_mutex);
return 0;
}
static int snd_mem_proc_open(struct inode *inode, struct file *file)
{
return single_open(file, snd_mem_proc_read, NULL);
}
/* FIXME: for pci only - other bus? */
#ifdef CONFIG_PCI
#define gettoken(bufp) strsep(bufp, " \t\n")
static ssize_t snd_mem_proc_write(struct file *file, const char __user * buffer,
size_t count, loff_t * ppos)
{
char buf[128];
char *token, *p;
if (count > sizeof(buf) - 1)
return -EINVAL;
if (copy_from_user(buf, buffer, count))
return -EFAULT;
buf[count] = '\0';
p = buf;
token = gettoken(&p);
if (! token || *token == '#')
return count;
if (strcmp(token, "add") == 0) {
char *endp;
int vendor, device, size, buffers;
long mask;
int i, alloced;
struct pci_dev *pci;
if ((token = gettoken(&p)) == NULL ||
(vendor = simple_strtol(token, NULL, 0)) <= 0 ||
(token = gettoken(&p)) == NULL ||
(device = simple_strtol(token, NULL, 0)) <= 0 ||
(token = gettoken(&p)) == NULL ||
(mask = simple_strtol(token, NULL, 0)) < 0 ||
(token = gettoken(&p)) == NULL ||
(size = memparse(token, &endp)) < 64*1024 ||
size > 16*1024*1024 /* too big */ ||
(token = gettoken(&p)) == NULL ||
(buffers = simple_strtol(token, NULL, 0)) <= 0 ||
buffers > 4) {
printk(KERN_ERR "snd-page-alloc: invalid proc write format\n");
return count;
}
vendor &= 0xffff;
device &= 0xffff;
alloced = 0;
pci = NULL;
while ((pci = pci_get_device(vendor, device, pci)) != NULL) {
if (mask > 0 && mask < 0xffffffff) {
if (pci_set_dma_mask(pci, mask) < 0 ||
pci_set_consistent_dma_mask(pci, mask) < 0) {
printk(KERN_ERR "snd-page-alloc: cannot set DMA mask %lx for pci %04x:%04x\n", mask, vendor, device);
pci_dev_put(pci);
return count;
}
}
for (i = 0; i < buffers; i++) {
struct snd_dma_buffer dmab;
memset(&dmab, 0, sizeof(dmab));
if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, snd_dma_pci_data(pci),
size, &dmab) < 0) {
printk(KERN_ERR "snd-page-alloc: cannot allocate buffer pages (size = %d)\n", size);
pci_dev_put(pci);
return count;
}
snd_dma_reserve_buf(&dmab, snd_dma_pci_buf_id(pci));
}
alloced++;
}
if (! alloced) {
for (i = 0; i < buffers; i++) {
struct snd_dma_buffer dmab;
memset(&dmab, 0, sizeof(dmab));
/* FIXME: We can allocate only in ZONE_DMA
* without a device pointer!
*/
if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, NULL,
size, &dmab) < 0) {
printk(KERN_ERR "snd-page-alloc: cannot allocate buffer pages (size = %d)\n", size);
break;
}
snd_dma_reserve_buf(&dmab, (unsigned int)((vendor << 16) | device));
}
}
} else if (strcmp(token, "erase") == 0)
/* FIXME: need for releasing each buffer chunk? */
free_all_reserved_pages();
else
printk(KERN_ERR "snd-page-alloc: invalid proc cmd\n");
return count;
}
#endif /* CONFIG_PCI */
static const struct file_operations snd_mem_proc_fops = {
.owner = THIS_MODULE,
.open = snd_mem_proc_open,
.read = seq_read,
#ifdef CONFIG_PCI
.write = snd_mem_proc_write,
#endif
.llseek = seq_lseek,
.release = single_release,
};
#endif /* CONFIG_PROC_FS */
/*
* module entry
*/
static int __init snd_mem_init(void)
{
#ifdef CONFIG_PROC_FS
snd_mem_proc = proc_create(SND_MEM_PROC_FILE, 0644, NULL,
&snd_mem_proc_fops);
#endif
return 0;
}
static void __exit snd_mem_exit(void)
{
remove_proc_entry(SND_MEM_PROC_FILE, NULL);
free_all_reserved_pages();
if (snd_allocated_pages > 0)
printk(KERN_ERR "snd-malloc: Memory leak? pages not freed = %li\n", snd_allocated_pages);
}
module_init(snd_mem_init)
module_exit(snd_mem_exit)
/*
* exports
*/
EXPORT_SYMBOL(snd_dma_alloc_pages);
EXPORT_SYMBOL(snd_dma_alloc_pages_fallback);
EXPORT_SYMBOL(snd_dma_free_pages);
EXPORT_SYMBOL(snd_dma_get_reserved_buf);
EXPORT_SYMBOL(snd_dma_reserve_buf);
EXPORT_SYMBOL(snd_malloc_pages);
EXPORT_SYMBOL(snd_free_pages);