So we can create GPU mappings without R/W permissions. Particularly useful to debug corruptions caused by out-of-bound writes.
Signed-off-by: Boris Brezillon boris.brezillon@collabora.com --- drivers/gpu/drm/panfrost/panfrost_drv.c | 14 ++++++++++++-- drivers/gpu/drm/panfrost/panfrost_gem.c | 2 ++ drivers/gpu/drm/panfrost/panfrost_gem.h | 2 ++ drivers/gpu/drm/panfrost/panfrost_mmu.c | 8 +++++++- include/uapi/drm/panfrost_drm.h | 2 ++ 5 files changed, 25 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panfrost/panfrost_drv.c index 82ad9a67f251..40e4a4db3ab1 100644 --- a/drivers/gpu/drm/panfrost/panfrost_drv.c +++ b/drivers/gpu/drm/panfrost/panfrost_drv.c @@ -75,6 +75,10 @@ static int panfrost_ioctl_get_param(struct drm_device *ddev, void *data, struct return 0; }
+#define PANFROST_BO_FLAGS \ + (PANFROST_BO_NOEXEC | PANFROST_BO_HEAP | \ + PANFROST_BO_NOREAD | PANFROST_BO_NOWRITE) + static int panfrost_ioctl_create_bo(struct drm_device *dev, void *data, struct drm_file *file) { @@ -84,7 +88,7 @@ static int panfrost_ioctl_create_bo(struct drm_device *dev, void *data, struct panfrost_gem_mapping *mapping;
if (!args->size || args->pad || - (args->flags & ~(PANFROST_BO_NOEXEC | PANFROST_BO_HEAP))) + (args->flags & ~PANFROST_BO_FLAGS)) return -EINVAL;
/* Heaps should never be executable */ @@ -92,6 +96,11 @@ static int panfrost_ioctl_create_bo(struct drm_device *dev, void *data, !(args->flags & PANFROST_BO_NOEXEC)) return -EINVAL;
+ /* Executable implies readable */ + if ((args->flags & PANFROST_BO_NOREAD) && + !(args->flags & PANFROST_BO_NOEXEC)) + return -EINVAL; + bo = panfrost_gem_create_with_handle(file, dev, args->size, args->flags, &args->handle); if (IS_ERR(bo)) @@ -520,6 +529,7 @@ DEFINE_DRM_GEM_FOPS(panfrost_drm_driver_fops); * - 1.0 - initial interface * - 1.1 - adds HEAP and NOEXEC flags for CREATE_BO * - 1.2 - adds AFBC_FEATURES query + * - 1.3 - adds PANFROST_BO_NO{READ,WRITE} flags */ static const struct drm_driver panfrost_drm_driver = { .driver_features = DRIVER_RENDER | DRIVER_GEM | DRIVER_SYNCOBJ, @@ -532,7 +542,7 @@ static const struct drm_driver panfrost_drm_driver = { .desc = "panfrost DRM", .date = "20180908", .major = 1, - .minor = 2, + .minor = 3,
.gem_create_object = panfrost_gem_create_object, .prime_handle_to_fd = drm_gem_prime_handle_to_fd, diff --git a/drivers/gpu/drm/panfrost/panfrost_gem.c b/drivers/gpu/drm/panfrost/panfrost_gem.c index 23377481f4e3..d6c1bb1445f2 100644 --- a/drivers/gpu/drm/panfrost/panfrost_gem.c +++ b/drivers/gpu/drm/panfrost/panfrost_gem.c @@ -251,6 +251,8 @@ panfrost_gem_create_with_handle(struct drm_file *file_priv,
bo = to_panfrost_bo(&shmem->base); bo->noexec = !!(flags & PANFROST_BO_NOEXEC); + bo->noread = !!(flags & PANFROST_BO_NOREAD); + bo->nowrite = !!(flags & PANFROST_BO_NOWRITE); bo->is_heap = !!(flags & PANFROST_BO_HEAP);
/* diff --git a/drivers/gpu/drm/panfrost/panfrost_gem.h b/drivers/gpu/drm/panfrost/panfrost_gem.h index 8088d5fd8480..6246b5fef446 100644 --- a/drivers/gpu/drm/panfrost/panfrost_gem.h +++ b/drivers/gpu/drm/panfrost/panfrost_gem.h @@ -37,6 +37,8 @@ struct panfrost_gem_object { atomic_t gpu_usecount;
bool noexec :1; + bool noread :1; + bool nowrite :1; bool is_heap :1; };
diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c index f51d3f791a17..6a5c9d94d6f2 100644 --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c @@ -307,7 +307,7 @@ int panfrost_mmu_map(struct panfrost_gem_mapping *mapping) struct drm_gem_object *obj = &bo->base.base; struct panfrost_device *pfdev = to_panfrost_device(obj->dev); struct sg_table *sgt; - int prot = IOMMU_READ | IOMMU_WRITE; + int prot = 0;
if (WARN_ON(mapping->active)) return 0; @@ -315,6 +315,12 @@ int panfrost_mmu_map(struct panfrost_gem_mapping *mapping) if (bo->noexec) prot |= IOMMU_NOEXEC;
+ if (!bo->nowrite) + prot |= IOMMU_WRITE; + + if (!bo->noread) + prot |= IOMMU_READ; + sgt = drm_gem_shmem_get_pages_sgt(obj); if (WARN_ON(IS_ERR(sgt))) return PTR_ERR(sgt); diff --git a/include/uapi/drm/panfrost_drm.h b/include/uapi/drm/panfrost_drm.h index 061e700dd06c..a2de81225125 100644 --- a/include/uapi/drm/panfrost_drm.h +++ b/include/uapi/drm/panfrost_drm.h @@ -86,6 +86,8 @@ struct drm_panfrost_wait_bo {
#define PANFROST_BO_NOEXEC 1 #define PANFROST_BO_HEAP 2 +#define PANFROST_BO_NOREAD 4 +#define PANFROST_BO_NOWRITE 8
/** * struct drm_panfrost_create_bo - ioctl argument for creating Panfrost BOs.