From 3afe7eb37f4d47f31d30a81c1b42ca02eab01e44 Mon Sep 17 00:00:00 2001 From: Alexander Belyakov Date: Thu, 25 Sep 2008 17:53:24 +0400 Subject: [PATCH] [MTD] [NOR] fix cfi_cmdset_0001 FL_SYNCING race (take 2) The patch fixes CFI issue with multipartitional devices leading to the set of errors or even deadlock. The problem is CFI FL_SYNCING state race with flash operations (e.g. erase suspend). It is reproduced by running intensive writes on one JFFS2 partition and simultaneously performing mount/unmount cycle on another partition of the same chip. Signed-off-by: Alexander Belyakov Acked-by: Nicolas Pitre Signed-off-by: David Woodhouse --- drivers/mtd/chips/cfi_cmdset_0001.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) diff --git a/drivers/mtd/chips/cfi_cmdset_0001.c b/drivers/mtd/chips/cfi_cmdset_0001.c index 5157e3cb4b9e..c93a8be5d5f1 100644 --- a/drivers/mtd/chips/cfi_cmdset_0001.c +++ b/drivers/mtd/chips/cfi_cmdset_0001.c @@ -725,6 +725,10 @@ static int chip_ready (struct map_info *map, struct flchip *chip, unsigned long struct cfi_pri_intelext *cfip = cfi->cmdset_priv; unsigned long timeo = jiffies + HZ; + /* Prevent setting state FL_SYNCING for chip in suspended state. */ + if (mode == FL_SYNCING && chip->oldstate != FL_READY) + goto sleep; + switch (chip->state) { case FL_STATUS: @@ -830,8 +834,9 @@ static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr DECLARE_WAITQUEUE(wait, current); retry: - if (chip->priv && (mode == FL_WRITING || mode == FL_ERASING - || mode == FL_OTP_WRITE || mode == FL_SHUTDOWN)) { + if (chip->priv && + (mode == FL_WRITING || mode == FL_ERASING || mode == FL_OTP_WRITE + || mode == FL_SHUTDOWN) && chip->state != FL_SYNCING) { /* * OK. We have possibility for contention on the write/erase * operations which are global to the real chip and not per @@ -881,6 +886,14 @@ static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr return ret; } spin_lock(&shared->lock); + + /* We should not own chip if it is already + * in FL_SYNCING state. Put contender and retry. */ + if (chip->state == FL_SYNCING) { + put_chip(map, contender, contender->start); + spin_unlock(contender->mutex); + goto retry; + } spin_unlock(contender->mutex); }