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>
diff --git a/drivers/block/rsxx/cregs.c b/drivers/block/rsxx/cregs.c
index 2241564..0539a25 100644
--- a/drivers/block/rsxx/cregs.c
+++ b/drivers/block/rsxx/cregs.c
@@ -99,22 +99,6 @@
}
}
-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 @@
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 @@
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 @@
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 @@
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 @@
"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 @@
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 @@
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 @@
"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);
}
