[PATCH AUTOSEL 5.1 043/375] drm/nouveau/bar/nv50: ensure BAR is mapped

Sasha Levin
2019-05-22T19:22:30Z

From: Jon Derrick <jonathan.derrick@intel.com>

[ Upstream commit f10b83de1fd49216a4c657816f48001437e4bdd5 ]

If the BAR is zero size, it indicates it was never successfully mapped.
Ensure that the BAR is valid during initialization before attempting to
use it.

Signed-off-by: Jon Derrick <jonathan.derrick@intel.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/nouveau/nvkm/subdev/bar/nv50.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/bar/nv50.c b/drivers/gpu/drm/nouveau/nvkm/subdev/bar/nv50.c
index 157b076a12723..38c9c086754b6 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/bar/nv50.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/bar/nv50.c
@@ -109,7 +109,7 @@ nv50_bar_oneinit(struct nvkm_bar *base)
struct nvkm_device *device = bar->base.subdev.device;
static struct lock_class_key bar1_lock;
static struct lock_class_key bar2_lock;
- u64 start, limit;
+ u64 start, limit, size;
int ret;

ret = nvkm_gpuobj_new(device, 0x20000, 0, false, NULL, &bar->mem);
@@ -127,7 +127,10 @@ nv50_bar_oneinit(struct nvkm_bar *base)

/* BAR2 */
start = 0x0100000000ULL;
- limit = start + device->func->resource_size(device, 3);
+ size = device->func->resource_size(device, 3);
+ if (!size)
+ return -ENOMEM;
+ limit = start + size;

ret = nvkm_vmm_new(device, start, limit-- - start, NULL, 0,
&bar2_lock, "bar2", &bar->bar2_vmm);
@@ -164,7 +167,10 @@ nv50_bar_oneinit(struct nvkm_bar *base)

/* BAR1 */
start = 0x0000000000ULL;
- limit = start + device->func->resource_size(device, 1);
+ size = device->func->resource_size(device, 1);
+ if (!size)
+ return -ENOMEM;
+ limit = start + size;

ret = nvkm_vmm_new(device, start, limit-- - start, NULL, 0,
&bar1_lock, "bar1", &bar->bar1_vmm);
--
2.20.1