korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-17 01:04:19 +08:00
Code Issues Packages Projects Releases Wiki Activity

[MIPS] RTLX: Protect rtlx_{read,write} with mutex.

Browse Source 
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
Ralf Baechle 2007-03-15 17:13:47 +00:00
parent 61dcc6f4d9
commit bc4809e939
1 changed files with 6 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
arch/mips/kernel/rtlx.c
View File

@ -54,6 +54,7 @@ static struct chan_waitqueues {
wait_queue_head_t rt_queue;
wait_queue_head_t lx_queue;
atomic_t in_open;
struct mutex mutex;
} channel_wqs[RTLX_CHANNELS];
static struct irqaction irq;
@ -314,6 +315,7 @@ ssize_t rtlx_read(int index, void *buff, size_t count, int user)
lx = &rtlx->channel[index];
mutex_lock(&channel_wqs[index].mutex);
smp_rmb();
lx_write = lx->lx_write;
@ -334,6 +336,7 @@ ssize_t rtlx_read(int index, void *buff, size_t count, int user)
smp_wmb();
lx->lx_read = (lx->lx_read + count) % lx->buffer_size;
smp_wmb();
mutex_unlock(&channel_wqs[index].mutex);
return count;
}
@ -349,6 +352,7 @@ ssize_t rtlx_write(int index, void *buffer, size_t count, int user)
rt = &rtlx->channel[index];
mutex_lock(&channel_wqs[index].mutex);
smp_rmb();
rt_read = rt->rt_read;
@ -368,6 +372,7 @@ ssize_t rtlx_write(int index, void *buffer, size_t count, int user)
smp_wmb();
rt->rt_write = (rt->rt_write + count) % rt->buffer_size;
smp_wmb();
mutex_unlock(&channel_wqs[index].mutex);
return count;
}
@ -486,6 +491,7 @@ static int rtlx_module_init(void)
init_waitqueue_head(&channel_wqs[i].rt_queue);
init_waitqueue_head(&channel_wqs[i].lx_queue);
atomic_set(&channel_wqs[i].in_open, 0);
mutex_init(&channel_wqs[i].mutex);
dev = device_create(mt_class, NULL, MKDEV(major, i),
"%s%d", module_name, i);