From 18034584784168c73bc8dd57104ea48c42f38527 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 18 Aug 2016 17:16:45 +0100 Subject: [PATCH] drm/i915: Fallback to single page pwrite/pread if unable to release fence If we cannot release the fence (for example if someone is inexplicably trying to write into a tiled framebuffer that is currently pinned to the display! *cough* kms_frontbuffer_tracking *cough*) fallback to using the page-by-page pwrite/pread interface, rather than fail the syscall entirely. Since this is triggerable by the user (along pwrite) we have to remove the WARN_ON(fence->pin_count). Signed-off-by: Chris Wilson Reviewed-by: Joonas Lahtinen Link: http://patchwork.freedesktop.org/patch/msgid/20160818161718.27187-6-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_gem.c | 30 ++++++++++++++++++------------ drivers/gpu/drm/i915/i915_gem_fence.c | 2 +- 2 files changed, 19 insertions(+), 13 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 5adbf8c..a609522 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -754,6 +754,15 @@ i915_gem_gtt_pread(struct drm_device *dev, int ret; vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, PIN_MAPPABLE); + if (!IS_ERR(vma)) { + node.start = i915_ggtt_offset(vma); + node.allocated = false; + ret = i915_gem_object_put_fence(obj); + if (ret) { + i915_vma_unpin(vma); + vma = ERR_PTR(ret); + } + } if (IS_ERR(vma)) { ret = insert_mappable_node(dev_priv, &node, PAGE_SIZE); if (ret) @@ -766,12 +775,6 @@ i915_gem_gtt_pread(struct drm_device *dev, } i915_gem_object_pin_pages(obj); - } else { - node.start = i915_ggtt_offset(vma); - node.allocated = false; - ret = i915_gem_object_put_fence(obj); - if (ret) - goto out_unpin; } ret = i915_gem_object_set_to_gtt_domain(obj, false); @@ -1058,6 +1061,15 @@ i915_gem_gtt_pwrite_fast(struct drm_i915_private *i915, vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, PIN_MAPPABLE | PIN_NONBLOCK); + if (!IS_ERR(vma)) { + node.start = i915_ggtt_offset(vma); + node.allocated = false; + ret = i915_gem_object_put_fence(obj); + if (ret) { + i915_vma_unpin(vma); + vma = ERR_PTR(ret); + } + } if (IS_ERR(vma)) { ret = insert_mappable_node(i915, &node, PAGE_SIZE); if (ret) @@ -1070,12 +1082,6 @@ i915_gem_gtt_pwrite_fast(struct drm_i915_private *i915, } i915_gem_object_pin_pages(obj); - } else { - node.start = i915_ggtt_offset(vma); - node.allocated = false; - ret = i915_gem_object_put_fence(obj); - if (ret) - goto out_unpin; } ret = i915_gem_object_set_to_gtt_domain(obj, true); diff --git a/drivers/gpu/drm/i915/i915_gem_fence.c b/drivers/gpu/drm/i915/i915_gem_fence.c index 334c3c4..b0c6c27 100644 --- a/drivers/gpu/drm/i915/i915_gem_fence.c +++ b/drivers/gpu/drm/i915/i915_gem_fence.c @@ -298,7 +298,7 @@ i915_gem_object_put_fence(struct drm_i915_gem_object *obj) fence = &dev_priv->fence_regs[obj->fence_reg]; - if (WARN_ON(fence->pin_count)) + if (fence->pin_count) return -EBUSY; i915_gem_object_fence_lost(obj); -- 2.7.4