[PATCH] use mutex instead of semaphore in DMA pool handler

From: Matthias Kaehlcke
Date: Tue Apr 24 2007 - 16:42:50 EST


the DMA pool handler uses a semaphore as mutex. use the mutex API
instead of the (binary) semaphore

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@xxxxxxxxx>

--

diff --git a/drivers/base/dmapool.c b/drivers/base/dmapool.c
index cd467c9..9406259 100644
--- a/drivers/base/dmapool.c
+++ b/drivers/base/dmapool.c
@@ -37,7 +37,7 @@ struct dma_page { /* cacheable header for 'allocation' bytes */

#define POOL_TIMEOUT_JIFFIES ((100 /* msec */ * HZ) / 1000)

-static DECLARE_MUTEX (pools_lock);
+static DEFINE_MUTEX (pools_lock);

static ssize_t
show_pools (struct device *dev, struct device_attribute *attr, char *buf)
@@ -55,7 +55,7 @@ show_pools (struct device *dev, struct device_attribute *attr, char *buf)
size -= temp;
next += temp;

- down (&pools_lock);
+ mutex_lock(&pools_lock);
list_for_each_entry(pool, &dev->dma_pools, pools) {
unsigned pages = 0;
unsigned blocks = 0;
@@ -73,7 +73,7 @@ show_pools (struct device *dev, struct device_attribute *attr, char *buf)
size -= temp;
next += temp;
}
- up (&pools_lock);
+ mutex_unlock(&pools_lock);

return PAGE_SIZE - size;
}
@@ -143,7 +143,7 @@ dma_pool_create (const char *name, struct device *dev,
if (dev) {
int ret;

- down (&pools_lock);
+ mutex_lock(&pools_lock);
if (list_empty (&dev->dma_pools))
ret = device_create_file (dev, &dev_attr_pools);
else
@@ -155,7 +155,7 @@ dma_pool_create (const char *name, struct device *dev,
kfree(retval);
retval = NULL;
}
- up (&pools_lock);
+ mutex_unlock(&pools_lock);
} else
INIT_LIST_HEAD (&retval->pools);

@@ -231,11 +231,11 @@ pool_free_page (struct dma_pool *pool, struct dma_page *page)
void
dma_pool_destroy (struct dma_pool *pool)
{
- down (&pools_lock);
+ mutex_lock(&pools_lock);
list_del (&pool->pools);
if (pool->dev && list_empty (&pool->dev->dma_pools))
device_remove_file (pool->dev, &dev_attr_pools);
- up (&pools_lock);
+ mutex_unlock(&pools_lock);

while (!list_empty (&pool->page_list)) {
struct dma_page *page;

--

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