leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

drm/i915/gem: Pull phys pread/pwrite implementations to the backend

Browse Source 
Move the specialised interactions with the physical GEM object from the
pread/pwrite ioctl handler into the phys backend.

Currently, if one is able to exhaust the entire aperture and then try to
pwrite into an object not backed by struct page, we accidentally invoked
the phys pwrite handler on a non-phys object; calamitous.

Fixes: c6790dc223 ("drm/i915: Wean off drm_pci_alloc/drm_pci_free")
Testcase: igt/gem_pwrite/exhaustion
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Cc: stable@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20201105154934.16022-2-chris@chris-wilson.co.uk
This commit is contained in:
Chris Wilson 2020-11-05 15:49:34 +00:00
parent 0049b68845
commit 852e1b3644
2 changed files with 55 additions and 26 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

55
drivers/gpu/drm/i915/gem/i915_gem_phys.c
View File

@ -134,6 +134,58 @@ i915_gem_object_put_pages_phys(struct drm_i915_gem_object *obj,
vaddr, dma);
}
static int
phys_pwrite(struct drm_i915_gem_object *obj,
const struct drm_i915_gem_pwrite *args)
{
void *vaddr = sg_page(obj->mm.pages->sgl) + args->offset;
char __user *user_data = u64_to_user_ptr(args->data_ptr);
int err;
err = i915_gem_object_wait(obj,
I915_WAIT_INTERRUPTIBLE |
I915_WAIT_ALL,
MAX_SCHEDULE_TIMEOUT);
if (err)
return err;
/*
* We manually control the domain here and pretend that it
* remains coherent i.e. in the GTT domain, like shmem_pwrite.
*/
i915_gem_object_invalidate_frontbuffer(obj, ORIGIN_CPU);
if (copy_from_user(vaddr, user_data, args->size))
return -EFAULT;
drm_clflush_virt_range(vaddr, args->size);
intel_gt_chipset_flush(&to_i915(obj->base.dev)->gt);
i915_gem_object_flush_frontbuffer(obj, ORIGIN_CPU);
return 0;
}
static int
phys_pread(struct drm_i915_gem_object *obj,
const struct drm_i915_gem_pread *args)
{
void *vaddr = sg_page(obj->mm.pages->sgl) + args->offset;
char __user *user_data = u64_to_user_ptr(args->data_ptr);
int err;
err = i915_gem_object_wait(obj,
I915_WAIT_INTERRUPTIBLE,
MAX_SCHEDULE_TIMEOUT);
if (err)
return err;
drm_clflush_virt_range(vaddr, args->size);
if (copy_to_user(user_data, vaddr, args->size))
return -EFAULT;
return 0;
}
static void phys_release(struct drm_i915_gem_object *obj)
{
fput(obj->base.filp);
@ -144,6 +196,9 @@ static const struct drm_i915_gem_object_ops i915_gem_phys_ops = {
.get_pages = i915_gem_object_get_pages_phys,
.put_pages = i915_gem_object_put_pages_phys,
.pread = phys_pread,
.pwrite = phys_pwrite,
.release = phys_release,
};

26
drivers/gpu/drm/i915/i915_gem.c
View File

@ -179,30 +179,6 @@ try_again:
return ret;
}
static int
i915_gem_phys_pwrite(struct drm_i915_gem_object *obj,
struct drm_i915_gem_pwrite *args,
struct drm_file *file)
{
void *vaddr = sg_page(obj->mm.pages->sgl) + args->offset;
char __user *user_data = u64_to_user_ptr(args->data_ptr);
/*
* We manually control the domain here and pretend that it
* remains coherent i.e. in the GTT domain, like shmem_pwrite.
*/
i915_gem_object_invalidate_frontbuffer(obj, ORIGIN_CPU);
if (copy_from_user(vaddr, user_data, args->size))
return -EFAULT;
drm_clflush_virt_range(vaddr, args->size);
intel_gt_chipset_flush(&to_i915(obj->base.dev)->gt);
i915_gem_object_flush_frontbuffer(obj, ORIGIN_CPU);
return 0;
}
static int
i915_gem_create(struct drm_file *file,
struct intel_memory_region *mr,
@ -872,8 +848,6 @@ i915_gem_pwrite_ioctl(struct drm_device *dev, void *data,
if (ret == -EFAULT || ret == -ENOSPC) {
if (i915_gem_object_has_struct_page(obj))
ret = i915_gem_shmem_pwrite(obj, args);
else
ret = i915_gem_phys_pwrite(obj, args, file);
}
i915_gem_object_unpin_pages(obj);