From a7b4c636d83034f0e89d58651ef2e9b96564489a Mon Sep 17 00:00:00 2001 From: Alexandre Bounine Date: Tue, 22 Mar 2016 14:26:35 -0700 Subject: [PATCH] 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 Cc: Matt Porter Cc: Aurelien Jacquiot Cc: Andre van Herk Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rapidio/rio.c | 9 ++++++--- include/linux/rio.h | 2 ++ 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/rapidio/rio.c b/drivers/rapidio/rio.c index 03b8c5af72bb..e42f97e9e62a 100644 --- a/drivers/rapidio/rio.c +++ b/drivers/rapidio/rio.c @@ -362,7 +362,9 @@ rio_setup_inb_dbell(struct rio_mport *mport, void *dev_id, struct resource *res, 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 rio_release_inb_dbell(struct rio_mport *mport, u16 start, u16 end) 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 @@ int rio_release_inb_dbell(struct rio_mport *mport, u16 start, u16 end) goto out; } - /* Delete from list */ - list_del(&dbell->node); - /* Release the doorbell resource */ rc = release_resource(dbell->res); @@ -2024,6 +2026,7 @@ int rio_mport_initialize(struct rio_mport *mport) 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 f833773cdc68..948f60550ae5 100644 --- a/include/linux/rio.h +++ b/include/linux/rio.h @@ -248,6 +248,7 @@ enum rio_phy_type { * @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 rio_mport { 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];