rapidio: add lock protection for doorbell list
Add lock protection around doorbell list handling to prevent list
corruption on SMP platforms.
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Andre van Herk <andre.van.herk@prodrive-technologies.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rapidio/rio.c b/drivers/rapidio/rio.c
index 03b8c5a..e42f97e 100644
--- a/drivers/rapidio/rio.c
+++ b/drivers/rapidio/rio.c
@@ -362,7 +362,9 @@
dbell->dinb = dinb;
dbell->dev_id = dev_id;
+ mutex_lock(&mport->lock);
list_add_tail(&dbell->node, &mport->dbells);
+ mutex_unlock(&mport->lock);
out:
return rc;
@@ -426,12 +428,15 @@
int rc = 0, found = 0;
struct rio_dbell *dbell;
+ mutex_lock(&mport->lock);
list_for_each_entry(dbell, &mport->dbells, node) {
if ((dbell->res->start == start) && (dbell->res->end == end)) {
+ list_del(&dbell->node);
found = 1;
break;
}
}
+ mutex_unlock(&mport->lock);
/* If we can't find an exact match, fail */
if (!found) {
@@ -439,9 +444,6 @@
goto out;
}
- /* Delete from list */
- list_del(&dbell->node);
-
/* Release the doorbell resource */
rc = release_resource(dbell->res);
@@ -2024,6 +2026,7 @@
mport->id = next_portid++;
mport->host_deviceid = rio_get_hdid(mport->id);
mport->nscan = NULL;
+ mutex_init(&mport->lock);
return 0;
}
diff --git a/include/linux/rio.h b/include/linux/rio.h
index f833773..948f605 100644
--- a/include/linux/rio.h
+++ b/include/linux/rio.h
@@ -248,6 +248,7 @@
* @node: Node in global list of master ports
* @nnode: Node in network list of master ports
* @net: RIO net this mport is attached to
+ * @lock: lock to synchronize lists manipulations
* @iores: I/O mem resource that this master port interface owns
* @riores: RIO resources that this master port interfaces owns
* @inb_msg: RIO inbound message event descriptors
@@ -271,6 +272,7 @@
struct list_head node; /* node in global list of ports */
struct list_head nnode; /* node in net list of ports */
struct rio_net *net; /* RIO net this mport is attached to */
+ struct mutex lock;
struct resource iores;
struct resource riores[RIO_MAX_MPORT_RESOURCES];
struct rio_msg inb_msg[RIO_MAX_MBOX];