gpu: nvgpu: add safety for vidmem addresses

Add new API set_vidmem_page_alloc() which sets BIT(0)
in sg_dma_address() only for vidmem allocation

Add and use new API get_vidmem_page_alloc() which
receives scatterlist and returns pointer to vidmem
allocation i.e. struct gk20a_page_alloc *alloc
In this API, check if BIT(0) is set or not in
sg_dma_address() before converting it to allocation
address

In gk20a_mm_smmu_vaddr_translate(), ensure that
the address is pure IOVA address by verifying that
BIT(0) is not set in that address

Jira DNVGPU-22

Change-Id: Ib53ff4b63ac59a8d870bc01d0af59839c6143334
Signed-off-by: Deepak Nibade <dnibade@nvidia.com>
Reviewed-on: http://git-master/r/1216142
(cherry picked from commit 03c9fbdaa40746dc43335cd8fbe9f97ef2ef50c9)
Reviewed-on: http://git-master/r/1219705
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 39 insertions, 13 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/mm_gk20a.c b/drivers/gpu/nvgpu/gk20a/mm_gk20a.c
index 555353e2..634ae86a 100644
--- a/drivers/gpu/nvgpu/gk20a/mm_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/mm_gk20a.c
@@ -58,6 +58,34 @@
 static void gk20a_vidmem_clear_mem_worker(struct work_struct *work);
 #endif
 
+static inline void
+set_vidmem_page_alloc(struct scatterlist *sgl, u64 addr)
+{
+        /* set bit 0 to indicate vidmem allocation */
+        sg_dma_address(sgl) = (addr | 1ULL);
+}
+
+static inline bool
+is_vidmem_page_alloc(u64 addr)
+{
+        return !!(addr & 1ULL);
+}
+
+static inline struct gk20a_page_alloc *
+get_vidmem_page_alloc(struct scatterlist *sgl)
+{
+        u64 addr;
+
+        addr = sg_dma_address(sgl);
+
+        if (is_vidmem_page_alloc(addr))
+                addr = addr & ~1ULL;
+        else
+                WARN_ON(1);
+
+        return (struct gk20a_page_alloc *)(uintptr_t)addr;
+}
+
 int gk20a_mem_begin(struct gk20a *g, struct mem_desc *mem)
 {
         void *cpu_va;
@@ -149,8 +177,7 @@ static inline void pramin_access_batched(struct gk20a *g, struct mem_desc *mem,
         struct page_alloc_chunk *chunk = NULL;
         u32 byteoff, start_reg, until_end, n;
 
-        alloc = (struct gk20a_page_alloc *)(uintptr_t)
-                                sg_dma_address(mem->sgt->sgl);
+        alloc = get_vidmem_page_alloc(mem->sgt->sgl);
         list_for_each_entry(chunk, &alloc->alloc_chunks, list_entry) {
                 if (offset >= chunk->length)
                         offset -= chunk->length;
@@ -2197,8 +2224,7 @@ static u64 gk20a_mm_get_align(struct gk20a *g, struct scatterlist *sgl,
         u64 buf_addr;
 
         if (aperture == APERTURE_VIDMEM) {
-                struct gk20a_page_alloc *alloc = (struct gk20a_page_alloc *)
-                                        (uintptr_t)sg_dma_address(sgl);
+                struct gk20a_page_alloc *alloc = get_vidmem_page_alloc(sgl);
                 struct page_alloc_chunk *chunk = NULL;
 
                 list_for_each_entry(chunk, &alloc->alloc_chunks, list_entry) {
@@ -2914,8 +2940,7 @@ static int gk20a_gmmu_clear_vidmem_mem(struct gk20a *g, struct mem_desc *mem)
         if (g->mm.vidmem.ce_ctx_id == ~0)
                 return -EINVAL;
 
-        alloc = (struct gk20a_page_alloc *)(uintptr_t)
-                        sg_dma_address(mem->sgt->sgl);
+        alloc = get_vidmem_page_alloc(mem->sgt->sgl);
 
         list_for_each_entry(chunk, &alloc->alloc_chunks, list_entry) {
                 if (gk20a_last_fence)
@@ -3038,7 +3063,7 @@ int gk20a_gmmu_alloc_attr_vid_at(struct gk20a *g, enum dma_attr attr,
         if (err)
                 goto fail_kfree;
 
-        sg_dma_address(mem->sgt->sgl) = addr;
+        set_vidmem_page_alloc(mem->sgt->sgl, addr);
         sg_set_page(mem->sgt->sgl, NULL, size, 0);
 
         mem->size = size;
@@ -3082,7 +3107,7 @@ static void gk20a_gmmu_free_attr_vid(struct gk20a *g, enum dma_attr attr,
         } else {
                 gk20a_memset(g, mem, 0, 0, mem->size);
                 gk20a_free(mem->allocator,
-                           sg_dma_address(mem->sgt->sgl));
+                           (u64)get_vidmem_page_alloc(mem->sgt->sgl));
                 gk20a_free_sgtable(&mem->sgt);
 
                 mem->size = 0;
@@ -3120,8 +3145,7 @@ u64 gk20a_mem_get_base_addr(struct gk20a *g, struct mem_desc *mem,
         u64 addr;
 
         if (mem->aperture == APERTURE_VIDMEM) {
-                alloc = (struct gk20a_page_alloc *)(uintptr_t)
-                                sg_dma_address(mem->sgt->sgl);
+                alloc = get_vidmem_page_alloc(mem->sgt->sgl);
 
                 /* This API should not be used with > 1 chunks */
                 WARN_ON(alloc->nr_chunks != 1);
@@ -3159,7 +3183,7 @@ static void gk20a_vidmem_clear_mem_worker(struct work_struct *work)
         while ((mem = get_pending_mem_desc(mm)) != NULL) {
                 gk20a_gmmu_clear_vidmem_mem(g, mem);
                 gk20a_free(mem->allocator,
-                           sg_dma_address(mem->sgt->sgl));
+                           (u64)get_vidmem_page_alloc(mem->sgt->sgl));
                 gk20a_free_sgtable(&mem->sgt);
 
                 WARN_ON(atomic_dec_return(&mm->vidmem.clears_pending) < 0);
@@ -3400,6 +3424,9 @@ void gk20a_free_sgtable(struct sg_table **sgt)
 
 u64 gk20a_mm_smmu_vaddr_translate(struct gk20a *g, dma_addr_t iova)
 {
+        /* ensure it is not vidmem allocation */
+        WARN_ON(is_vidmem_page_alloc((u64)iova));
+
         if (device_is_iommuable(dev_from_gk20a(g)) &&
                         g->ops.mm.get_physical_addr_bits)
                 return iova | 1ULL << g->ops.mm.get_physical_addr_bits(g);
@@ -3747,8 +3774,7 @@ static int update_gmmu_ptes_locked(struct vm_gk20a *vm,
                                 pgsz_idx, gpu_va, gpu_end-1, iova);
 
                 if (sgt) {
-                        alloc = (struct gk20a_page_alloc *)(uintptr_t)
-                                        sg_dma_address(sgt->sgl);
+                        alloc = get_vidmem_page_alloc(sgt->sgl);
 
                         list_for_each_entry(chunk, &alloc->alloc_chunks,
                                                         list_entry) {