Re: [PATCH] [CFI] Prevent erase command invocation on suspended chip

Nicolas Pitre
2007-11-07T13:44:31Z

On Wed, 7 Nov 2007, Alexander Belyakov wrote:

> Hello,
>
> while running stress tests we have met cfi_cmdset_0001.c driver issue.
> Working on multipartitional devices with erase suspend on write
> feature enabled it is possible to get erase operation invoked on chip
> with suspended erase. get_chip() looses information about earlier
> suspended erase and new erase operation gets issued. New erase
> operations report successful completion, but blocks remain dirty
> causing, for example, JFFS2 error messages like:
>
> ...
> Newly-erased block contained word 0x20031985 at offset 0x00200000
> Newly-erased block contained word 0x20031985 at offset 0x00280000
> Newly-erased block contained word 0x20031985 at offset 0x00240000
> ...
>
>
> The patch below fixes that issue.
>
> Signed-off-by: Alexander Belyakov <alexander.belyakov@intel.com>

Acked-by: Nicolas Pitre <nico@cam.org>

>
> diff -uNr a/drivers/mtd/chips/cfi_cmdset_0001.c
> b/drivers/mtd/chips/cfi_cmdset_0001.c
> --- a/drivers/mtd/chips/cfi_cmdset_0001.c 2007-11-06 11:40:24.000000000 +0300
> +++ b/drivers/mtd/chips/cfi_cmdset_0001.c 2007-11-06 20:37:03.000000000 +0300
> @@ -795,6 +795,7 @@
> static int get_chip(struct map_info *map, struct flchip *chip,
> unsigned long adr, int mode)
> {
> int ret;
> + DECLARE_WAITQUEUE(wait, current);
>
> retry:
> if (chip->priv && (mode == FL_WRITING || mode == FL_ERASING
> @@ -851,6 +852,20 @@
> spin_unlock(contender->mutex);
> }
>
> + /* Check if we already have suspended erase
> + * on this chip. Sleep. */
> + if (mode == FL_ERASING && shared->erasing
> + && shared->erasing->oldstate == FL_ERASING) {
> + spin_unlock(&shared->lock);
> + set_current_state(TASK_UNINTERRUPTIBLE);
> + add_wait_queue(&chip->wq, &wait);
> + spin_unlock(chip->mutex);
> + schedule();
> + remove_wait_queue(&chip->wq, &wait);
> + spin_lock(chip->mutex);
> + goto retry;
> + }
> +
> /* We now own it */
> shared->writing = chip;
> if (mode == FL_ERASING)
>

Nicolas