drm/i915: use i915_sg_dma_sizes() for all backends

We rely on page_sizes.sg in setup_scratch_page() reporting the correct
value if the underlying sgl is not contiguous, however in
get_pages_internal() we are only looking at the layout of the created
pages when calculating the sg_page_sizes, and not the final sgl, which
could in theory be completely different. In such a situation we might
incorrectly think we have a 64K scratch page, when it is actually only
4K or similar split over multiple non-contiguous entries, which could
lead to broken behaviour when touching the scratch space within the
padding of a 64K GTT page-table. For most of the other backends we
already just call i915_sg_dma_sizes() on the final mapping, so rather
just move that into __i915_gem_object_set_pages() to avoid such issues
coming back to bite us later.

v2: Update missing conversion in gvt

Suggested-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Stuart Summers <stuart.summers@intel.com>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221108103238.165447-1-matthew.auld@intel.com

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c
index ec6f7ae..1df74f7 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c
@@ -238,7 +238,6 @@ static int i915_gem_object_get_pages_dmabuf(struct drm_i915_gem_object *obj)
 {
        struct drm_i915_private *i915 = to_i915(obj->base.dev);
        struct sg_table *sgt;
-       unsigned int sg_page_sizes;
 
        assert_object_held(obj);
 
@@ -262,8 +261,7 @@ static int i915_gem_object_get_pages_dmabuf(struct drm_i915_gem_object *obj)
            (!HAS_LLC(i915) && !IS_DG1(i915)))
                wbinvd_on_all_cpus();
 
-       sg_page_sizes = i915_sg_dma_sizes(sgt->sgl);
-       __i915_gem_object_set_pages(obj, sgt, sg_page_sizes);
+       __i915_gem_object_set_pages(obj, sgt);
 
        return 0;
 }

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_internal.c b/drivers/gpu/drm/i915/gem/i915_gem_internal.c
index 629acb4..f66bcef 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_internal.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_internal.c
@@ -35,7 +35,6 @@ static int i915_gem_object_get_pages_internal(struct drm_i915_gem_object *obj)
        struct drm_i915_private *i915 = to_i915(obj->base.dev);
        struct sg_table *st;
        struct scatterlist *sg;
-       unsigned int sg_page_sizes;
        unsigned int npages;
        int max_order = MAX_ORDER;
        unsigned int max_segment;
@@ -64,7 +63,6 @@ create_st:
 
        sg = st->sgl;
        st->nents = 0;
-       sg_page_sizes = 0;
 
        do {
                int order = min(fls(npages) - 1, max_order);
@@ -83,7 +81,6 @@ create_st:
                } while (1);
 
                sg_set_page(sg, page, PAGE_SIZE << order, 0);
-               sg_page_sizes |= PAGE_SIZE << order;
                st->nents++;
 
                npages -= 1 << order;
@@ -105,7 +102,7 @@ create_st:
                goto err;
        }
 
-       __i915_gem_object_set_pages(obj, st, sg_page_sizes);
+       __i915_gem_object_set_pages(obj, st);
 
        return 0;
 

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h
index 6b9ecff..3db5376 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_object.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h
@@ -403,8 +403,7 @@ i915_gem_object_get_dma_address(struct drm_i915_gem_object *obj,
                                unsigned long n);
 
 void __i915_gem_object_set_pages(struct drm_i915_gem_object *obj,
-                                struct sg_table *pages,
-                                unsigned int sg_page_sizes);
+                                struct sg_table *pages);
 
 int ____i915_gem_object_get_pages(struct drm_i915_gem_object *obj);
 int __i915_gem_object_get_pages(struct drm_i915_gem_object *obj);

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_pages.c b/drivers/gpu/drm/i915/gem/i915_gem_pages.c
index 16f8456..05a2772 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_pages.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_pages.c
@@ -16,8 +16,7 @@
 #include "i915_gem_mman.h"
 
 void __i915_gem_object_set_pages(struct drm_i915_gem_object *obj,
-                                struct sg_table *pages,
-                                unsigned int sg_page_sizes)
+                                struct sg_table *pages)
 {
        struct drm_i915_private *i915 = to_i915(obj->base.dev);
        unsigned long supported = RUNTIME_INFO(i915)->page_sizes;
@@ -45,8 +44,8 @@ void __i915_gem_object_set_pages(struct drm_i915_gem_object *obj,
 
        obj->mm.pages = pages;
 
-       GEM_BUG_ON(!sg_page_sizes);
-       obj->mm.page_sizes.phys = sg_page_sizes;
+       obj->mm.page_sizes.phys = i915_sg_dma_sizes(pages->sgl);
+       GEM_BUG_ON(!obj->mm.page_sizes.phys);
 
        /*
         * Calculate the supported page-sizes which fit into the given

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_phys.c b/drivers/gpu/drm/i915/gem/i915_gem_phys.c
index 0d0e46d..6845357 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_phys.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_phys.c
@@ -79,7 +79,7 @@ static int i915_gem_object_get_pages_phys(struct drm_i915_gem_object *obj)
 
        /* We're no longer struct page backed */
        obj->mem_flags &= ~I915_BO_FLAG_STRUCT_PAGE;
-       __i915_gem_object_set_pages(obj, st, sg->length);
+       __i915_gem_object_set_pages(obj, st);
 
        return 0;
 
@@ -209,11 +209,8 @@ static int i915_gem_object_shmem_to_phys(struct drm_i915_gem_object *obj)
        return 0;
 
 err_xfer:
-       if (!IS_ERR_OR_NULL(pages)) {
-               unsigned int sg_page_sizes = i915_sg_dma_sizes(pages->sgl);
-
-               __i915_gem_object_set_pages(obj, pages, sg_page_sizes);
-       }
+       if (!IS_ERR_OR_NULL(pages))
+               __i915_gem_object_set_pages(obj, pages);
        return err;
 }
 

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
index 2f78044..9c759df 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
@@ -247,7 +247,7 @@ rebuild_st:
        if (i915_gem_object_can_bypass_llc(obj))
                obj->cache_dirty = true;
 
-       __i915_gem_object_set_pages(obj, st, i915_sg_dma_sizes(st->sgl));
+       __i915_gem_object_set_pages(obj, st);
 
        return 0;
 

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
index 0c70711..bc95210 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
@@ -628,7 +628,7 @@ static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
                   sg_dma_len(pages->sgl),
                   POISON_INUSE);
 
-       __i915_gem_object_set_pages(obj, pages, obj->stolen->size);
+       __i915_gem_object_set_pages(obj, pages);
 
        return 0;
 }

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
index 2c8b2d5..e4e55e3 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
@@ -815,8 +815,7 @@ static int __i915_ttm_get_pages(struct drm_i915_gem_object *obj,
 
                GEM_BUG_ON(obj->mm.rsgt);
                obj->mm.rsgt = rsgt;
-               __i915_gem_object_set_pages(obj, &rsgt->table,
-                                           i915_sg_dma_sizes(rsgt->table.sgl));
+               __i915_gem_object_set_pages(obj, &rsgt->table);
        }
 
        GEM_BUG_ON(bo->ttm && ((obj->base.size >> PAGE_SHIFT) < bo->ttm->num_pages));

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
index ca7a388..9348b18 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
@@ -131,7 +131,6 @@ static int i915_gem_userptr_get_pages(struct drm_i915_gem_object *obj)
        const unsigned long num_pages = obj->base.size >> PAGE_SHIFT;
        unsigned int max_segment = i915_sg_segment_size(obj->base.dev->dev);
        struct sg_table *st;
-       unsigned int sg_page_sizes;
        struct page **pvec;
        int ret;
 
@@ -170,8 +169,7 @@ alloc_table:
        if (i915_gem_object_can_bypass_llc(obj))
                obj->cache_dirty = true;
 
-       sg_page_sizes = i915_sg_dma_sizes(st->sgl);
-       __i915_gem_object_set_pages(obj, st, sg_page_sizes);
+       __i915_gem_object_set_pages(obj, st);
 
        return 0;
 

diff --git a/drivers/gpu/drm/i915/gem/selftests/huge_gem_object.c b/drivers/gpu/drm/i915/gem/selftests/huge_gem_object.c
index f963b8e..cbd9b62 100644 (file)
--- a/drivers/gpu/drm/i915/gem/selftests/huge_gem_object.c
+++ b/drivers/gpu/drm/i915/gem/selftests/huge_gem_object.c
@@ -68,7 +68,7 @@ static int huge_get_pages(struct drm_i915_gem_object *obj)
        if (i915_gem_gtt_prepare_pages(obj, pages))
                goto err;
 
-       __i915_gem_object_set_pages(obj, pages, PAGE_SIZE);
+       __i915_gem_object_set_pages(obj, pages);
 
        return 0;
 

diff --git a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c b/drivers/gpu/drm/i915/gem/selftests/huge_pages.c
index 0cb99e7..beaf27e 100644 (file)
--- a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c
+++ b/drivers/gpu/drm/i915/gem/selftests/huge_pages.c
@@ -136,7 +136,7 @@ static int get_huge_pages(struct drm_i915_gem_object *obj)
                goto err;
 
        GEM_BUG_ON(sg_page_sizes != obj->mm.page_mask);
-       __i915_gem_object_set_pages(obj, st, sg_page_sizes);
+       __i915_gem_object_set_pages(obj, st);
 
        return 0;
 
@@ -210,7 +210,6 @@ static int fake_get_huge_pages(struct drm_i915_gem_object *obj)
        const u64 max_len = rounddown_pow_of_two(UINT_MAX);
        struct sg_table *st;
        struct scatterlist *sg;
-       unsigned int sg_page_sizes;
        u64 rem;
 
        st = kmalloc(sizeof(*st), GFP);
@@ -226,7 +225,6 @@ static int fake_get_huge_pages(struct drm_i915_gem_object *obj)
        rem = obj->base.size;
        sg = st->sgl;
        st->nents = 0;
-       sg_page_sizes = 0;
        do {
                unsigned int page_size = get_largest_page_size(i915, rem);
                unsigned int len = min(page_size * div_u64(rem, page_size),
@@ -239,8 +237,6 @@ static int fake_get_huge_pages(struct drm_i915_gem_object *obj)
                sg_dma_len(sg) = len;
                sg_dma_address(sg) = page_size;
 
-               sg_page_sizes |= len;
-
                st->nents++;
 
                rem -= len;
@@ -254,7 +250,7 @@ static int fake_get_huge_pages(struct drm_i915_gem_object *obj)
 
        i915_sg_trim(st);
 
-       __i915_gem_object_set_pages(obj, st, sg_page_sizes);
+       __i915_gem_object_set_pages(obj, st);
 
        return 0;
 }
@@ -286,7 +282,7 @@ static int fake_get_huge_pages_single(struct drm_i915_gem_object *obj)
        sg_dma_len(sg) = obj->base.size;
        sg_dma_address(sg) = page_size;
 
-       __i915_gem_object_set_pages(obj, st, sg->length);
+       __i915_gem_object_set_pages(obj, st);
 
        return 0;
 #undef GFP

diff --git a/drivers/gpu/drm/i915/gvt/dmabuf.c b/drivers/gpu/drm/i915/gvt/dmabuf.c
index 01e54b4..355f1c0 100644 (file)
--- a/drivers/gpu/drm/i915/gvt/dmabuf.c
+++ b/drivers/gpu/drm/i915/gvt/dmabuf.c
@@ -88,7 +88,7 @@ static int vgpu_gem_get_pages(
                sg_dma_address(sg) = dma_addr;
        }
 
-       __i915_gem_object_set_pages(obj, st, PAGE_SIZE);
+       __i915_gem_object_set_pages(obj, st);
 out:
        if (ret) {
                dma_addr_t dma_addr;

diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
index 27c733b..eae7d94 100644 (file)
--- a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
@@ -61,7 +61,6 @@ static int fake_get_pages(struct drm_i915_gem_object *obj)
 #define PFN_BIAS 0x1000
        struct sg_table *pages;
        struct scatterlist *sg;
-       unsigned int sg_page_sizes;
        typeof(obj->base.size) rem;
 
        pages = kmalloc(sizeof(*pages), GFP);
@@ -74,7 +73,6 @@ static int fake_get_pages(struct drm_i915_gem_object *obj)
                return -ENOMEM;
        }
 
-       sg_page_sizes = 0;
        rem = obj->base.size;
        for (sg = pages->sgl; sg; sg = sg_next(sg)) {
                unsigned long len = min_t(typeof(rem), rem, BIT(31));
@@ -83,13 +81,12 @@ static int fake_get_pages(struct drm_i915_gem_object *obj)
                sg_set_page(sg, pfn_to_page(PFN_BIAS), len, 0);
                sg_dma_address(sg) = page_to_phys(sg_page(sg));
                sg_dma_len(sg) = len;
-               sg_page_sizes |= len;
 
                rem -= len;
        }
        GEM_BUG_ON(rem);
 
-       __i915_gem_object_set_pages(obj, pages, sg_page_sizes);
+       __i915_gem_object_set_pages(obj, pages);
 
        return 0;
 #undef GFP

diff --git a/drivers/gpu/drm/i915/selftests/mock_region.c b/drivers/gpu/drm/i915/selftests/mock_region.c
index bac21fe..6324eb3 100644 (file)
--- a/drivers/gpu/drm/i915/selftests/mock_region.c
+++ b/drivers/gpu/drm/i915/selftests/mock_region.c
@@ -41,7 +41,7 @@ static int mock_region_get_pages(struct drm_i915_gem_object *obj)
        }
 
        pages = &obj->mm.rsgt->table;
-       __i915_gem_object_set_pages(obj, pages, i915_sg_dma_sizes(pages->sgl));
+       __i915_gem_object_set_pages(obj, pages);
 
        return 0;