dmaengine: idxd: fix wq settings post wq disable

commit 0f225705cf6536826318180831e18a74595efc8d upstream.

By the spec, wq size and group association is not changeable unless device
is disabled. Exclude clearing the shadow copy on wq disable/reset. This
allows wq type to be changed after disable to be re-enabled.

Move the size and group association to its own cleanup and only call it
during device disable.

Fixes: 0dcfe41e9a4c ("dmanegine: idxd: cleanup all device related bits after disabling device")
Reported-by: Lucas Van <lucas.van@intel.com>
Tested-by: Lucas Van <lucas.van@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163951291732.2987775.13576571320501115257.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/dma/idxd/device.c b/drivers/dma/idxd/device.c
index 419b206..b468ca3 100644 (file)
--- a/drivers/dma/idxd/device.c
+++ b/drivers/dma/idxd/device.c
@@ -394,8 +394,6 @@ static void idxd_wq_disable_cleanup(struct idxd_wq *wq)
        lockdep_assert_held(&wq->wq_lock);
        memset(wq->wqcfg, 0, idxd->wqcfg_size);
        wq->type = IDXD_WQT_NONE;
-       wq->size = 0;
-       wq->group = NULL;
        wq->threshold = 0;
        wq->priority = 0;
        wq->ats_dis = 0;
@@ -404,6 +402,15 @@ static void idxd_wq_disable_cleanup(struct idxd_wq *wq)
        memset(wq->name, 0, WQ_NAME_SIZE);
 }
 
+static void idxd_wq_device_reset_cleanup(struct idxd_wq *wq)
+{
+       lockdep_assert_held(&wq->wq_lock);
+
+       idxd_wq_disable_cleanup(wq);
+       wq->size = 0;
+       wq->group = NULL;
+}
+
 static void idxd_wq_ref_release(struct percpu_ref *ref)
 {
        struct idxd_wq *wq = container_of(ref, struct idxd_wq, wq_active);
@@ -711,6 +718,7 @@ static void idxd_device_wqs_clear_state(struct idxd_device *idxd)
 
                if (wq->state == IDXD_WQ_ENABLED) {
                        idxd_wq_disable_cleanup(wq);
+                       idxd_wq_device_reset_cleanup(wq);
                        wq->state = IDXD_WQ_DISABLED;
                }
        }