[PATCH] convert fs/9p/ to mutexes, fix locking bugs

Convert fs/9p/mux.c from semaphore to mutex.

NOTE: fixed locking bugs in the process - the code was using semaphores
the other way around.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Ingo Molnar 2006-03-23 03:00:19 -08:00 committed by Linus Torvalds
parent 9331b3157c
commit 4f7a07b887

View file

@ -31,6 +31,7 @@
#include <linux/poll.h>
#include <linux/kthread.h>
#include <linux/idr.h>
#include <linux/mutex.h>
#include "debug.h"
#include "v9fs.h"
@ -110,7 +111,7 @@ static void v9fs_pollwait(struct file *filp, wait_queue_head_t * wait_address,
static u16 v9fs_mux_get_tag(struct v9fs_mux_data *);
static void v9fs_mux_put_tag(struct v9fs_mux_data *, u16);
static DECLARE_MUTEX(v9fs_mux_task_lock);
static DEFINE_MUTEX(v9fs_mux_task_lock);
static struct workqueue_struct *v9fs_mux_wq;
static int v9fs_mux_num;
@ -166,7 +167,7 @@ static int v9fs_mux_poll_start(struct v9fs_mux_data *m)
dprintk(DEBUG_MUX, "mux %p muxnum %d procnum %d\n", m, v9fs_mux_num,
v9fs_mux_poll_task_num);
up(&v9fs_mux_task_lock);
mutex_lock(&v9fs_mux_task_lock);
n = v9fs_mux_calc_poll_procs(v9fs_mux_num + 1);
if (n > v9fs_mux_poll_task_num) {
@ -225,7 +226,7 @@ static int v9fs_mux_poll_start(struct v9fs_mux_data *m)
}
v9fs_mux_num++;
down(&v9fs_mux_task_lock);
mutex_unlock(&v9fs_mux_task_lock);
return 0;
}
@ -235,7 +236,7 @@ static void v9fs_mux_poll_stop(struct v9fs_mux_data *m)
int i;
struct v9fs_mux_poll_task *vpt;
up(&v9fs_mux_task_lock);
mutex_lock(&v9fs_mux_task_lock);
vpt = m->poll_task;
list_del(&m->mux_list);
for(i = 0; i < ARRAY_SIZE(m->poll_waddr); i++) {
@ -252,7 +253,7 @@ static void v9fs_mux_poll_stop(struct v9fs_mux_data *m)
v9fs_mux_poll_task_num--;
}
v9fs_mux_num--;
down(&v9fs_mux_task_lock);
mutex_unlock(&v9fs_mux_task_lock);
}
/**