The msm driver implements a custom dumb_map_offset callback. This implementation acquires the msm_gem_lock, but the underlying drm_gem_create_mmap_offset() function is already thread-safe regarding the VMA offset manager (it acquires the mgr->vm_lock internally).
Switching to the generic drm_gem_dumb_map_offset() helper provides several benefits: 1. Removes the unnecessary locking overhead (locking leftovers). 2. Adds a missing check to reject mapping of imported objects, which is invalid for dumb buffers. 3. Allows for the removal of the msm_gem_dumb_map_offset() wrapper and the msm_gem_mmap_offset() helper function. The logic from msm_gem_mmap_offset() has been inlined into msm_ioctl_gem_info() to maintain functionality without the separate helper. This addresses the TODO: "Documentation/gpu/todo.rst: Remove custom dumb_map_offset implementations" Signed-off-by: Swaraj Gaikwad <[email protected]> --- Compile-tested only. drivers/gpu/drm/msm/msm_drv.c | 8 +++--- drivers/gpu/drm/msm/msm_gem.c | 49 ----------------------------------- drivers/gpu/drm/msm/msm_gem.h | 3 --- 3 files changed, 5 insertions(+), 55 deletions(-) diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c index 7e977fec4100..bf20550c5814 100644 --- a/drivers/gpu/drm/msm/msm_drv.c +++ b/drivers/gpu/drm/msm/msm_drv.c @@ -588,7 +588,9 @@ static int msm_ioctl_gem_info(struct drm_device *dev, void *data, switch (args->info) { case MSM_INFO_GET_OFFSET: - args->value = msm_gem_mmap_offset(obj); + ret = drm_gem_create_mmap_offset(obj); + if (ret == 0) + args->value = drm_vma_node_offset_addr(&obj->vma_node); break; case MSM_INFO_GET_IOVA: ret = msm_ioctl_gem_info_iova(dev, file, obj, &args->value); @@ -836,7 +838,7 @@ static const struct drm_driver msm_driver = { .open = msm_open, .postclose = msm_postclose, .dumb_create = msm_gem_dumb_create, - .dumb_map_offset = msm_gem_dumb_map_offset, + .dumb_map_offset = drm_gem_dumb_map_offset, .gem_prime_import = msm_gem_prime_import, .gem_prime_import_sg_table = msm_gem_prime_import_sg_table, #ifdef CONFIG_DEBUG_FS @@ -859,7 +861,7 @@ static const struct drm_driver msm_kms_driver = { .open = msm_open, .postclose = msm_postclose, .dumb_create = msm_gem_dumb_create, - .dumb_map_offset = msm_gem_dumb_map_offset, + .dumb_map_offset = drm_gem_dumb_map_offset, .gem_prime_import_sg_table = msm_gem_prime_import_sg_table, #ifdef CONFIG_DEBUG_FS .debugfs_init = msm_debugfs_init, diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c index 017411a0bf45..da74f1413f94 100644 --- a/drivers/gpu/drm/msm/msm_gem.c +++ b/drivers/gpu/drm/msm/msm_gem.c @@ -375,34 +375,6 @@ static vm_fault_t msm_gem_fault(struct vm_fault *vmf) return ret; } -/** get mmap offset */ -static uint64_t mmap_offset(struct drm_gem_object *obj) -{ - struct drm_device *dev = obj->dev; - int ret; - - msm_gem_assert_locked(obj); - - /* Make it mmapable */ - ret = drm_gem_create_mmap_offset(obj); - - if (ret) { - DRM_DEV_ERROR(dev->dev, "could not allocate mmap offset\n"); - return 0; - } - - return drm_vma_node_offset_addr(&obj->vma_node); -} - -uint64_t msm_gem_mmap_offset(struct drm_gem_object *obj) -{ - uint64_t offset; - - msm_gem_lock(obj); - offset = mmap_offset(obj); - msm_gem_unlock(obj); - return offset; -} static struct drm_gpuva *lookup_vma(struct drm_gem_object *obj, struct drm_gpuvm *vm) @@ -730,27 +702,6 @@ int msm_gem_dumb_create(struct drm_file *file, struct drm_device *dev, MSM_BO_SCANOUT | MSM_BO_WC, &args->handle, "dumb"); } -int msm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev, - uint32_t handle, uint64_t *offset) -{ - struct drm_gem_object *obj; - int ret = 0; - - /* GEM does all our handle to object mapping */ - obj = drm_gem_object_lookup(file, handle); - if (obj == NULL) { - ret = -ENOENT; - goto fail; - } - - *offset = msm_gem_mmap_offset(obj); - - drm_gem_object_put(obj); - -fail: - return ret; -} - static void *get_vaddr(struct drm_gem_object *obj, unsigned madv) { struct msm_gem_object *msm_obj = to_msm_bo(obj); diff --git a/drivers/gpu/drm/msm/msm_gem.h b/drivers/gpu/drm/msm/msm_gem.h index a4cf31853c50..92ada1d69250 100644 --- a/drivers/gpu/drm/msm/msm_gem.h +++ b/drivers/gpu/drm/msm/msm_gem.h @@ -262,7 +262,6 @@ struct msm_gem_object { void msm_gem_vma_get(struct drm_gem_object *obj); void msm_gem_vma_put(struct drm_gem_object *obj); -uint64_t msm_gem_mmap_offset(struct drm_gem_object *obj); int msm_gem_prot(struct drm_gem_object *obj); int msm_gem_pin_vma_locked(struct drm_gem_object *obj, struct drm_gpuva *vma); void msm_gem_unpin_locked(struct drm_gem_object *obj); @@ -285,8 +284,6 @@ struct page **msm_gem_pin_pages_locked(struct drm_gem_object *obj); void msm_gem_unpin_pages_locked(struct drm_gem_object *obj); int msm_gem_dumb_create(struct drm_file *file, struct drm_device *dev, struct drm_mode_create_dumb *args); -int msm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev, - uint32_t handle, uint64_t *offset); void *msm_gem_get_vaddr_locked(struct drm_gem_object *obj); void *msm_gem_get_vaddr(struct drm_gem_object *obj); void *msm_gem_get_vaddr_active(struct drm_gem_object *obj); base-commit: 8f0b4cce4481fb22653697cced8d0d04027cb1e8 -- 2.52.0
