[PATCH v2 16/18] drm/i915: Check against correct user_size limit in 48b ppgtt mode

Michel Thierry
2015-06-10T16:47:26Z

GTT is only 32b and its max value is 4GB. In order to allow objects
bigger than 4GB in 48b PPGTT, i915_gem_userptr_ioctl needs to check
against max 48b range (1ULL << 48).

Whenever possible, read the PPGTT's total instead of the GTT one, this
will be accurate in 32 and 48 bit modes.

v2: Use the default ctx to infer the ppgtt max size (Akash).

Cc: Akash Goel <akash.goel@intel.com>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
---
drivers/gpu/drm/i915/i915_gem_userptr.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_userptr.c b/drivers/gpu/drm/i915/i915_gem_userptr.c
index 1f4e5a3..9783415 100644
--- a/drivers/gpu/drm/i915/i915_gem_userptr.c
+++ b/drivers/gpu/drm/i915/i915_gem_userptr.c
@@ -789,8 +789,10 @@ int
i915_gem_userptr_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
{
struct drm_i915_private *dev_priv = dev->dev_private;
+ struct drm_i915_file_private *file_priv = file->driver_priv;
struct drm_i915_gem_userptr *args = data;
struct drm_i915_gem_object *obj;
+ struct intel_context *ctx;
int ret;
u32 handle;

@@ -801,8 +803,14 @@ i915_gem_userptr_ioctl(struct drm_device *dev, void *data, struct drm_file *file
if (offset_in_page(args->user_ptr | args->user_size))
return -EINVAL;

- if (args->user_size > dev_priv->gtt.base.total)
- return -E2BIG;
+ ctx = i915_gem_context_get(file_priv, DEFAULT_CONTEXT_HANDLE);
+ if (ctx->ppgtt) {
+ if (args->user_size > ctx->ppgtt->base.total)
+ return -E2BIG;
+ } else {
+ if (args->user_size > dev_priv->gtt.base.total)
+ return -E2BIG;
+ }

if (!access_ok(args->flags & I915_USERPTR_READ_ONLY ? VERIFY_READ : VERIFY_WRITE,
(char __user *)(unsigned long)args->user_ptr, args->user_size))
--
2.4.0