[PATCH 03/20] drm/i915/gtt: Check va range against vm size

Mika Kuoppala
2015-05-21T14:37:52Z

Check the allocation area against the known end
of address space instead of against fixed value.

v2: Return ENODEV on internal bugs (Chris)

Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
---
drivers/gpu/drm/i915/i915_gem_gtt.c | 18 +++++++++++-------
1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 0ffd459..6f79680 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -756,9 +756,6 @@ static int gen8_ppgtt_alloc_page_directories(struct i915_hw_ppgtt *ppgtt,

WARN_ON(!bitmap_empty(new_pds, GEN8_LEGACY_PDPES));

- /* FIXME: upper bound must not overflow 32 bits */
- WARN_ON((start + length) > (1ULL << 32));
-
gen8_for_each_pdpe(pd, pdp, start, length, temp, pdpe) {
if (pd)
continue;
@@ -857,7 +854,10 @@ static int gen8_alloc_va_range(struct i915_address_space *vm,
* actually use the other side of the canonical address space.
*/
if (WARN_ON(start + length < start))
- return -ERANGE;
+ return -ENODEV;
+
+ if (WARN_ON(start + length > ppgtt->base.total))
+ return -ENODEV;

ret = alloc_gen8_temp_bitmaps(&new_page_dirs, &new_page_tables);
if (ret)
@@ -1291,7 +1291,7 @@ static void gen6_initialize_pt(struct i915_address_space *vm,
}

static int gen6_alloc_va_range(struct i915_address_space *vm,
- uint64_t start, uint64_t length)
+ uint64_t start_in, uint64_t length_in)
{
DECLARE_BITMAP(new_page_tables, I915_PDES);
struct drm_device *dev = vm->dev;
@@ -1299,11 +1299,15 @@ static int gen6_alloc_va_range(struct i915_address_space *vm,
struct i915_hw_ppgtt *ppgtt =
container_of(vm, struct i915_hw_ppgtt, base);
struct i915_page_table *pt;
- const uint32_t start_save = start, length_save = length;
+ uint32_t start, length, start_save, length_save;
uint32_t pde, temp;
int ret;

- WARN_ON(upper_32_bits(start));
+ if (WARN_ON(start_in + length_in > ppgtt->base.total))
+ return -ENODEV;
+
+ start = start_save = start_in;
+ length = length_save = length_in;

bitmap_zero(new_page_tables, I915_PDES);