[PATCH 8/8] MTD: make mtdtrans thread freezeable.

From: Maxim Levitsky
Date: Fri Jan 22 2010 - 19:26:34 EST


>From ebc69b9819f963a17574aa42e93f409368acdfaa Mon Sep 17 00:00:00 2001
From: Maxim Levitsky <maximlevitsky@xxxxxxxxx>
Date: Sat, 23 Jan 2010 02:09:33 +0200
Subject: [PATCH 8/8] MTD: make mtdtrans thread freezeable.

This makes the mtd blktrans thread enter the freezer in between accesses
to nand device.
This will ensure that we aren't suspening the system in the middle
of page read/write and even worse erase, which is a bad idea.

Signed-off-by: Maxim Levitsky <maximlevitsky@xxxxxxxxx>
---
drivers/mtd/mtd_blkdevs.c | 14 +++++++-------
1 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/mtd/mtd_blkdevs.c b/drivers/mtd/mtd_blkdevs.c
index 33bdef1..ed82396 100644
--- a/drivers/mtd/mtd_blkdevs.c
+++ b/drivers/mtd/mtd_blkdevs.c
@@ -20,6 +20,7 @@
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/kthread.h>
+#include <linux/freezer.h>
#include <asm/uaccess.h>

#include "mtdcore.h"
@@ -79,36 +80,35 @@ static int mtd_blktrans_thread(void *arg)
struct request_queue *rq = dev->rq;
struct request *req = NULL;

- spin_lock_irq(rq->queue_lock);
+ set_freezable();

while (!kthread_should_stop()) {
int res;

+ try_to_freeze();
+
+ spin_lock_irq(rq->queue_lock);
if (!req && !(req = blk_fetch_request(rq))) {
set_current_state(TASK_INTERRUPTIBLE);
spin_unlock_irq(rq->queue_lock);
schedule();
- spin_lock_irq(rq->queue_lock);
continue;
}
-
spin_unlock_irq(rq->queue_lock);

+
mutex_lock(&dev->lock);
res = do_blktrans_request(dev->tr, dev, req);
mutex_unlock(&dev->lock);

spin_lock_irq(rq->queue_lock);
-
if (!__blk_end_request_cur(req, res))
req = NULL;
+ spin_unlock_irq(rq->queue_lock);
}

if (req)
__blk_end_request_all(req, -EIO);
-
- spin_unlock_irq(rq->queue_lock);
-
return 0;
}

--
1.6.3.3



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/