diff options
author | Philip J Kelleher <pjk1939@linux.vnet.ibm.com> | 2013-02-25 12:31:31 -0600 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2013-03-11 19:53:55 +0100 |
commit | 03ac03a8971bd7e9f8c8b20a309b61beaf154d60 (patch) | |
tree | 310c2b5750e53387f45a4144e4454b181143bdc4 /drivers/block | |
parent | f37912039eb04979f269de0a7dc1a601702df51a (diff) |
block: IBM RamSan 70/80 fixes inconsistent locking.
This patch includes changes to the cregs locking scheme. Before,
inconsistant locking would occur because of misuse of spin_lock,
spin_lock_bh, and counter parts.
Signed-off-by: Philip J Kelleher <pjk1939@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/block')
-rw-r--r-- | drivers/block/rsxx/cregs.c | 44 |
1 files changed, 18 insertions, 26 deletions
diff --git a/drivers/block/rsxx/cregs.c b/drivers/block/rsxx/cregs.c index 224156435261..0539a25877eb 100644 --- a/drivers/block/rsxx/cregs.c +++ b/drivers/block/rsxx/cregs.c @@ -99,22 +99,6 @@ static void copy_from_creg_data(struct rsxx_cardinfo *card, } } -static struct creg_cmd *pop_active_cmd(struct rsxx_cardinfo *card) -{ - struct creg_cmd *cmd; - - /* - * Spin lock is needed because this can be called in atomic/interrupt - * context. - */ - spin_lock_bh(&card->creg_ctrl.lock); - cmd = card->creg_ctrl.active_cmd; - card->creg_ctrl.active_cmd = NULL; - spin_unlock_bh(&card->creg_ctrl.lock); - - return cmd; -} - static void creg_issue_cmd(struct rsxx_cardinfo *card, struct creg_cmd *cmd) { iowrite32(cmd->addr, card->regmap + CREG_ADD); @@ -189,11 +173,11 @@ static int creg_queue_cmd(struct rsxx_cardinfo *card, cmd->cb_private = cb_private; cmd->status = 0; - spin_lock(&card->creg_ctrl.lock); + spin_lock_bh(&card->creg_ctrl.lock); list_add_tail(&cmd->list, &card->creg_ctrl.queue); card->creg_ctrl.q_depth++; creg_kick_queue(card); - spin_unlock(&card->creg_ctrl.lock); + spin_unlock_bh(&card->creg_ctrl.lock); return 0; } @@ -203,7 +187,11 @@ static void creg_cmd_timed_out(unsigned long data) struct rsxx_cardinfo *card = (struct rsxx_cardinfo *) data; struct creg_cmd *cmd; - cmd = pop_active_cmd(card); + spin_lock(&card->creg_ctrl.lock); + cmd = card->creg_ctrl.active_cmd; + card->creg_ctrl.active_cmd = NULL; + spin_unlock(&card->creg_ctrl.lock); + if (cmd == NULL) { card->creg_ctrl.creg_stats.creg_timeout++; dev_warn(CARD_TO_DEV(card), @@ -240,7 +228,11 @@ static void creg_cmd_done(struct work_struct *work) if (del_timer_sync(&card->creg_ctrl.cmd_timer) == 0) card->creg_ctrl.creg_stats.failed_cancel_timer++; - cmd = pop_active_cmd(card); + spin_lock_bh(&card->creg_ctrl.lock); + cmd = card->creg_ctrl.active_cmd; + card->creg_ctrl.active_cmd = NULL; + spin_unlock_bh(&card->creg_ctrl.lock); + if (cmd == NULL) { dev_err(CARD_TO_DEV(card), "Spurious creg interrupt!\n"); @@ -289,10 +281,10 @@ creg_done: kmem_cache_free(creg_cmd_pool, cmd); - spin_lock(&card->creg_ctrl.lock); + spin_lock_bh(&card->creg_ctrl.lock); card->creg_ctrl.active = 0; creg_kick_queue(card); - spin_unlock(&card->creg_ctrl.lock); + spin_unlock_bh(&card->creg_ctrl.lock); } static void creg_reset(struct rsxx_cardinfo *card) @@ -317,7 +309,7 @@ static void creg_reset(struct rsxx_cardinfo *card) "Resetting creg interface for recovery\n"); /* Cancel outstanding commands */ - spin_lock(&card->creg_ctrl.lock); + spin_lock_bh(&card->creg_ctrl.lock); list_for_each_entry_safe(cmd, tmp, &card->creg_ctrl.queue, list) { list_del(&cmd->list); card->creg_ctrl.q_depth--; @@ -338,7 +330,7 @@ static void creg_reset(struct rsxx_cardinfo *card) card->creg_ctrl.active = 0; } - spin_unlock(&card->creg_ctrl.lock); + spin_unlock_bh(&card->creg_ctrl.lock); card->creg_ctrl.reset = 0; spin_lock_irqsave(&card->irq_lock, flags); @@ -705,7 +697,7 @@ void rsxx_creg_destroy(struct rsxx_cardinfo *card) int cnt = 0; /* Cancel outstanding commands */ - spin_lock(&card->creg_ctrl.lock); + spin_lock_bh(&card->creg_ctrl.lock); list_for_each_entry_safe(cmd, tmp, &card->creg_ctrl.queue, list) { list_del(&cmd->list); if (cmd->cb) @@ -730,7 +722,7 @@ void rsxx_creg_destroy(struct rsxx_cardinfo *card) "Canceled active creg command\n"); kmem_cache_free(creg_cmd_pool, cmd); } - spin_unlock(&card->creg_ctrl.lock); + spin_unlock_bh(&card->creg_ctrl.lock); cancel_work_sync(&card->creg_ctrl.done_work); } |