From cb2ce93e5b050fb9182eb6b6ff64428333436f73 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 27 Nov 2020 19:53:34 +0000 Subject: [PATCH] drm/i915/gem: Differentiate oom failures from invalid map types After a cursory check on the parameters to i915_gem_object_pin_map(), where we return a precise error, if the backend rejects the mapping we always return PTR_ERR(-ENOMEM). Let us also return a more precise error here so we can differentiate between running out of memory and programming errors (or situations where we may be trying different paths and looking for an error from an unsupported map). Signed-off-by: Chris Wilson Cc: Matthew Auld Reviewed-by: Matthew Auld Link: https://patchwork.freedesktop.org/patch/msgid/20201127195334.13134-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/gem/i915_gem_pages.c | 26 ++++++++++++-------------- 1 file changed, 12 insertions(+), 14 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_pages.c b/drivers/gpu/drm/i915/gem/i915_gem_pages.c index e2c7b2a..6dad9ea 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_pages.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_pages.c @@ -238,7 +238,7 @@ unlock: /* The 'mapping' part of i915_gem_object_pin_map() below */ static void *i915_gem_object_map_page(struct drm_i915_gem_object *obj, - enum i915_map_type type) + enum i915_map_type type) { unsigned long n_pages = obj->base.size >> PAGE_SHIFT, i; struct page *stack[32], **pages = stack, *page; @@ -281,7 +281,7 @@ static void *i915_gem_object_map_page(struct drm_i915_gem_object *obj, /* Too big for stack -- allocate temporary array instead */ pages = kvmalloc_array(n_pages, sizeof(*pages), GFP_KERNEL); if (!pages) - return NULL; + return ERR_PTR(-ENOMEM); } i = 0; @@ -294,7 +294,7 @@ static void *i915_gem_object_map_page(struct drm_i915_gem_object *obj, } static void *i915_gem_object_map_pfn(struct drm_i915_gem_object *obj, - enum i915_map_type type) + enum i915_map_type type) { resource_size_t iomap = obj->mm.region->iomap.base - obj->mm.region->region.start; @@ -305,13 +305,13 @@ static void *i915_gem_object_map_pfn(struct drm_i915_gem_object *obj, void *vaddr; if (type != I915_MAP_WC) - return NULL; + return ERR_PTR(-ENODEV); if (n_pfn > ARRAY_SIZE(stack)) { /* Too big for stack -- allocate temporary array instead */ pfns = kvmalloc_array(n_pfn, sizeof(*pfns), GFP_KERNEL); if (!pfns) - return NULL; + return ERR_PTR(-ENOMEM); } i = 0; @@ -349,8 +349,10 @@ void *i915_gem_object_pin_map(struct drm_i915_gem_object *obj, GEM_BUG_ON(i915_gem_object_has_pinned_pages(obj)); err = ____i915_gem_object_get_pages(obj); - if (err) - goto err_unlock; + if (err) { + ptr = ERR_PTR(err); + goto out_unlock; + } smp_mb__before_atomic(); } @@ -362,7 +364,7 @@ void *i915_gem_object_pin_map(struct drm_i915_gem_object *obj, ptr = page_unpack_bits(obj->mm.mapping, &has_type); if (ptr && has_type != type) { if (pinned) { - err = -EBUSY; + ptr = ERR_PTR(-EBUSY); goto err_unpin; } @@ -374,15 +376,13 @@ void *i915_gem_object_pin_map(struct drm_i915_gem_object *obj, if (!ptr) { if (GEM_WARN_ON(type == I915_MAP_WC && !static_cpu_has(X86_FEATURE_PAT))) - ptr = NULL; + ptr = ERR_PTR(-ENODEV); else if (i915_gem_object_has_struct_page(obj)) ptr = i915_gem_object_map_page(obj, type); else ptr = i915_gem_object_map_pfn(obj, type); - if (!ptr) { - err = -ENOMEM; + if (IS_ERR(ptr)) goto err_unpin; - } obj->mm.mapping = page_pack_bits(ptr, type); } @@ -393,8 +393,6 @@ out_unlock: err_unpin: atomic_dec(&obj->mm.pages_pin_count); -err_unlock: - ptr = ERR_PTR(err); goto out_unlock; } -- 2.7.4