From: Matthew Auld matthew.auld@intel.com
[ Upstream commit aff1e0b09b54b64944b7fe32997229552737b9e9 ]
If we encounter some monster sized local-memory page that exceeds the maximum sg length (UINT32_MAX), ensure that don't end up with some misaligned address in the entry that follows, leading to fireworks later. Also ensure we have some coverage of this in the selftests.
v2(Chris): - Use round_down consistently to avoid udiv errors v3(Nirmoy): - Also update the max_segment in the selftest
Fixes: f701b16d4cc5 ("drm/i915/ttm: add i915_sg_from_buddy_resource") Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/6379 Signed-off-by: Matthew Auld matthew.auld@intel.com Cc: Thomas Hellström thomas.hellstrom@linux.intel.com Cc: Nirmoy Das nirmoy.das@linux.intel.com Reviewed-by: Nirmoy Das nirmoy.das@intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20220711085859.24198-1-matthew... (cherry picked from commit bc99f1209f19fefa3ee11e77464ccfae541f4291) Signed-off-by: Rodrigo Vivi rodrigo.vivi@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 11 ++++++++-- drivers/gpu/drm/i915/i915_scatterlist.c | 19 +++++++++++++---- drivers/gpu/drm/i915/i915_scatterlist.h | 6 ++++-- drivers/gpu/drm/i915/intel_region_ttm.c | 10 ++++++--- drivers/gpu/drm/i915/intel_region_ttm.h | 3 ++- .../drm/i915/selftests/intel_memory_region.c | 21 +++++++++++++++++-- drivers/gpu/drm/i915/selftests/mock_region.c | 3 ++- 7 files changed, 58 insertions(+), 15 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c index 45cc5837ce00..342ca303eae4 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c @@ -583,10 +583,15 @@ i915_ttm_resource_get_st(struct drm_i915_gem_object *obj, struct ttm_resource *res) { struct ttm_buffer_object *bo = i915_gem_to_ttm(obj); + u64 page_alignment;
if (!i915_ttm_gtt_binds_lmem(res)) return i915_ttm_tt_get_st(bo->ttm);
+ page_alignment = bo->page_alignment << PAGE_SHIFT; + if (!page_alignment) + page_alignment = obj->mm.region->min_page_size; + /* * If CPU mapping differs, we need to add the ttm_tt pages to * the resulting st. Might make sense for GGTT. @@ -597,7 +602,8 @@ i915_ttm_resource_get_st(struct drm_i915_gem_object *obj, struct i915_refct_sgt *rsgt;
rsgt = intel_region_ttm_resource_to_rsgt(obj->mm.region, - res); + res, + page_alignment); if (IS_ERR(rsgt)) return rsgt;
@@ -606,7 +612,8 @@ i915_ttm_resource_get_st(struct drm_i915_gem_object *obj, return i915_refct_sgt_get(obj->ttm.cached_io_rsgt); }
- return intel_region_ttm_resource_to_rsgt(obj->mm.region, res); + return intel_region_ttm_resource_to_rsgt(obj->mm.region, res, + page_alignment); }
static int i915_ttm_truncate(struct drm_i915_gem_object *obj) diff --git a/drivers/gpu/drm/i915/i915_scatterlist.c b/drivers/gpu/drm/i915/i915_scatterlist.c index 159571b9bd24..f63b50b71e10 100644 --- a/drivers/gpu/drm/i915/i915_scatterlist.c +++ b/drivers/gpu/drm/i915/i915_scatterlist.c @@ -68,6 +68,7 @@ void i915_refct_sgt_init(struct i915_refct_sgt *rsgt, size_t size) * drm_mm_node * @node: The drm_mm_node. * @region_start: An offset to add to the dma addresses of the sg list. + * @page_alignment: Required page alignment for each sg entry. Power of two. * * Create a struct sg_table, initializing it from a struct drm_mm_node, * taking a maximum segment length into account, splitting into segments @@ -77,15 +78,18 @@ void i915_refct_sgt_init(struct i915_refct_sgt *rsgt, size_t size) * error code cast to an error pointer on failure. */ struct i915_refct_sgt *i915_rsgt_from_mm_node(const struct drm_mm_node *node, - u64 region_start) + u64 region_start, + u64 page_alignment) { - const u64 max_segment = SZ_1G; /* Do we have a limit on this? */ + const u64 max_segment = round_down(UINT_MAX, page_alignment); u64 segment_pages = max_segment >> PAGE_SHIFT; u64 block_size, offset, prev_end; struct i915_refct_sgt *rsgt; struct sg_table *st; struct scatterlist *sg;
+ GEM_BUG_ON(!max_segment); + rsgt = kmalloc(sizeof(*rsgt), GFP_KERNEL); if (!rsgt) return ERR_PTR(-ENOMEM); @@ -112,6 +116,8 @@ struct i915_refct_sgt *i915_rsgt_from_mm_node(const struct drm_mm_node *node, sg = __sg_next(sg);
sg_dma_address(sg) = region_start + offset; + GEM_BUG_ON(!IS_ALIGNED(sg_dma_address(sg), + page_alignment)); sg_dma_len(sg) = 0; sg->length = 0; st->nents++; @@ -138,6 +144,7 @@ struct i915_refct_sgt *i915_rsgt_from_mm_node(const struct drm_mm_node *node, * i915_buddy_block list * @res: The struct i915_ttm_buddy_resource. * @region_start: An offset to add to the dma addresses of the sg list. + * @page_alignment: Required page alignment for each sg entry. Power of two. * * Create a struct sg_table, initializing it from struct i915_buddy_block list, * taking a maximum segment length into account, splitting into segments @@ -147,11 +154,12 @@ struct i915_refct_sgt *i915_rsgt_from_mm_node(const struct drm_mm_node *node, * error code cast to an error pointer on failure. */ struct i915_refct_sgt *i915_rsgt_from_buddy_resource(struct ttm_resource *res, - u64 region_start) + u64 region_start, + u64 page_alignment) { struct i915_ttm_buddy_resource *bman_res = to_ttm_buddy_resource(res); const u64 size = res->num_pages << PAGE_SHIFT; - const u64 max_segment = rounddown(UINT_MAX, PAGE_SIZE); + const u64 max_segment = round_down(UINT_MAX, page_alignment); struct drm_buddy *mm = bman_res->mm; struct list_head *blocks = &bman_res->blocks; struct drm_buddy_block *block; @@ -161,6 +169,7 @@ struct i915_refct_sgt *i915_rsgt_from_buddy_resource(struct ttm_resource *res, resource_size_t prev_end;
GEM_BUG_ON(list_empty(blocks)); + GEM_BUG_ON(!max_segment);
rsgt = kmalloc(sizeof(*rsgt), GFP_KERNEL); if (!rsgt) @@ -191,6 +200,8 @@ struct i915_refct_sgt *i915_rsgt_from_buddy_resource(struct ttm_resource *res, sg = __sg_next(sg);
sg_dma_address(sg) = region_start + offset; + GEM_BUG_ON(!IS_ALIGNED(sg_dma_address(sg), + page_alignment)); sg_dma_len(sg) = 0; sg->length = 0; st->nents++; diff --git a/drivers/gpu/drm/i915/i915_scatterlist.h b/drivers/gpu/drm/i915/i915_scatterlist.h index 12c6a1684081..b13e4cdea923 100644 --- a/drivers/gpu/drm/i915/i915_scatterlist.h +++ b/drivers/gpu/drm/i915/i915_scatterlist.h @@ -213,9 +213,11 @@ static inline void __i915_refct_sgt_init(struct i915_refct_sgt *rsgt, void i915_refct_sgt_init(struct i915_refct_sgt *rsgt, size_t size);
struct i915_refct_sgt *i915_rsgt_from_mm_node(const struct drm_mm_node *node, - u64 region_start); + u64 region_start, + u64 page_alignment);
struct i915_refct_sgt *i915_rsgt_from_buddy_resource(struct ttm_resource *res, - u64 region_start); + u64 region_start, + u64 page_alignment);
#endif diff --git a/drivers/gpu/drm/i915/intel_region_ttm.c b/drivers/gpu/drm/i915/intel_region_ttm.c index 737ef3f4ab54..d896558cf458 100644 --- a/drivers/gpu/drm/i915/intel_region_ttm.c +++ b/drivers/gpu/drm/i915/intel_region_ttm.c @@ -151,6 +151,7 @@ int intel_region_ttm_fini(struct intel_memory_region *mem) * Convert an opaque TTM resource manager resource to a refcounted sg_table. * @mem: The memory region. * @res: The resource manager resource obtained from the TTM resource manager. + * @page_alignment: Required page alignment for each sg entry. Power of two. * * The gem backends typically use sg-tables for operations on the underlying * io_memory. So provide a way for the backends to translate the @@ -160,16 +161,19 @@ int intel_region_ttm_fini(struct intel_memory_region *mem) */ struct i915_refct_sgt * intel_region_ttm_resource_to_rsgt(struct intel_memory_region *mem, - struct ttm_resource *res) + struct ttm_resource *res, + u64 page_alignment) { if (mem->is_range_manager) { struct ttm_range_mgr_node *range_node = to_ttm_range_mgr_node(res);
return i915_rsgt_from_mm_node(&range_node->mm_nodes[0], - mem->region.start); + mem->region.start, + page_alignment); } else { - return i915_rsgt_from_buddy_resource(res, mem->region.start); + return i915_rsgt_from_buddy_resource(res, mem->region.start, + page_alignment); } }
diff --git a/drivers/gpu/drm/i915/intel_region_ttm.h b/drivers/gpu/drm/i915/intel_region_ttm.h index fdee5e7bd46c..b17e494ef79c 100644 --- a/drivers/gpu/drm/i915/intel_region_ttm.h +++ b/drivers/gpu/drm/i915/intel_region_ttm.h @@ -24,7 +24,8 @@ int intel_region_ttm_fini(struct intel_memory_region *mem);
struct i915_refct_sgt * intel_region_ttm_resource_to_rsgt(struct intel_memory_region *mem, - struct ttm_resource *res); + struct ttm_resource *res, + u64 page_alignment);
void intel_region_ttm_resource_free(struct intel_memory_region *mem, struct ttm_resource *res); diff --git a/drivers/gpu/drm/i915/selftests/intel_memory_region.c b/drivers/gpu/drm/i915/selftests/intel_memory_region.c index ba32893e0873..0250a114fe0a 100644 --- a/drivers/gpu/drm/i915/selftests/intel_memory_region.c +++ b/drivers/gpu/drm/i915/selftests/intel_memory_region.c @@ -451,7 +451,6 @@ static int igt_mock_splintered_region(void *arg)
static int igt_mock_max_segment(void *arg) { - const unsigned int max_segment = rounddown(UINT_MAX, PAGE_SIZE); struct intel_memory_region *mem = arg; struct drm_i915_private *i915 = mem->i915; struct i915_ttm_buddy_resource *res; @@ -460,7 +459,10 @@ static int igt_mock_max_segment(void *arg) struct drm_buddy *mm; struct list_head *blocks; struct scatterlist *sg; + I915_RND_STATE(prng); LIST_HEAD(objects); + unsigned int max_segment; + unsigned int ps; u64 size; int err = 0;
@@ -472,7 +474,13 @@ static int igt_mock_max_segment(void *arg) */
size = SZ_8G; - mem = mock_region_create(i915, 0, size, PAGE_SIZE, 0, 0); + ps = PAGE_SIZE; + if (i915_prandom_u64_state(&prng) & 1) + ps = SZ_64K; /* For something like DG2 */ + + max_segment = round_down(UINT_MAX, ps); + + mem = mock_region_create(i915, 0, size, ps, 0, 0); if (IS_ERR(mem)) return PTR_ERR(mem);
@@ -498,12 +506,21 @@ static int igt_mock_max_segment(void *arg) }
for (sg = obj->mm.pages->sgl; sg; sg = sg_next(sg)) { + dma_addr_t daddr = sg_dma_address(sg); + if (sg->length > max_segment) { pr_err("%s: Created an oversized scatterlist entry, %u > %u\n", __func__, sg->length, max_segment); err = -EINVAL; goto out_close; } + + if (!IS_ALIGNED(daddr, ps)) { + pr_err("%s: Created an unaligned scatterlist entry, addr=%pa, ps=%u\n", + __func__, &daddr, ps); + err = -EINVAL; + goto out_close; + } }
out_close: diff --git a/drivers/gpu/drm/i915/selftests/mock_region.c b/drivers/gpu/drm/i915/selftests/mock_region.c index f64325491f35..6f7c9820d3e9 100644 --- a/drivers/gpu/drm/i915/selftests/mock_region.c +++ b/drivers/gpu/drm/i915/selftests/mock_region.c @@ -32,7 +32,8 @@ static int mock_region_get_pages(struct drm_i915_gem_object *obj) return PTR_ERR(obj->mm.res);
obj->mm.rsgt = intel_region_ttm_resource_to_rsgt(obj->mm.region, - obj->mm.res); + obj->mm.res, + obj->mm.region->min_page_size); if (IS_ERR(obj->mm.rsgt)) { err = PTR_ERR(obj->mm.rsgt); goto err_free_resource;