drm/i915: introduce mem->reserved

In the following patch we need to reserve regions unaccessible to the
driver during initialization, so add mem->reserved for collecting such
regions.

v2: turn into an actual intel_memory_region_reserve api

Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20210127131417.393872-4-matthew.auld@intel.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/intel_memory_region.c b/drivers/gpu/drm/i915/intel_memory_region.c
index b1b610b..49d306b 100644 (file)
--- a/drivers/gpu/drm/i915/intel_memory_region.c
+++ b/drivers/gpu/drm/i915/intel_memory_region.c
@@ -156,9 +156,22 @@ int intel_memory_region_init_buddy(struct intel_memory_region *mem)
 
 void intel_memory_region_release_buddy(struct intel_memory_region *mem)
 {
+       i915_buddy_free_list(&mem->mm, &mem->reserved);
        i915_buddy_fini(&mem->mm);
 }
 
+int intel_memory_region_reserve(struct intel_memory_region *mem,
+                               u64 offset, u64 size)
+{
+       int ret;
+
+       mutex_lock(&mem->mm_lock);
+       ret = i915_buddy_alloc_range(&mem->mm, &mem->reserved, offset, size);
+       mutex_unlock(&mem->mm_lock);
+
+       return ret;
+}
+
 struct intel_memory_region *
 intel_memory_region_create(struct drm_i915_private *i915,
                           resource_size_t start,
@@ -185,6 +198,7 @@ intel_memory_region_create(struct drm_i915_private *i915,
        mutex_init(&mem->objects.lock);
        INIT_LIST_HEAD(&mem->objects.list);
        INIT_LIST_HEAD(&mem->objects.purgeable);
+       INIT_LIST_HEAD(&mem->reserved);
 
        mutex_init(&mem->mm_lock);
 

diff --git a/drivers/gpu/drm/i915/intel_memory_region.h b/drivers/gpu/drm/i915/intel_memory_region.h
index 6ffc067..d17e4fe 100644 (file)
--- a/drivers/gpu/drm/i915/intel_memory_region.h
+++ b/drivers/gpu/drm/i915/intel_memory_region.h
@@ -89,6 +89,8 @@ struct intel_memory_region {
        unsigned int id;
        char name[8];
 
+       struct list_head reserved;
+
        dma_addr_t remap_addr;
 
        struct {
@@ -113,6 +115,9 @@ void __intel_memory_region_put_pages_buddy(struct intel_memory_region *mem,
                                           struct list_head *blocks);
 void __intel_memory_region_put_block_buddy(struct i915_buddy_block *block);
 
+int intel_memory_region_reserve(struct intel_memory_region *mem,
+                               u64 offset, u64 size);
+
 struct intel_memory_region *
 intel_memory_region_create(struct drm_i915_private *i915,
                           resource_size_t start,

diff --git a/drivers/gpu/drm/i915/selftests/intel_memory_region.c b/drivers/gpu/drm/i915/selftests/intel_memory_region.c
index ce7adfa..6434852 100644 (file)
--- a/drivers/gpu/drm/i915/selftests/intel_memory_region.c
+++ b/drivers/gpu/drm/i915/selftests/intel_memory_region.c
@@ -144,6 +144,82 @@ static bool is_contiguous(struct drm_i915_gem_object *obj)
        return true;
 }
 
+static int igt_mock_reserve(void *arg)
+{
+       struct intel_memory_region *mem = arg;
+       resource_size_t avail = resource_size(&mem->region);
+       struct drm_i915_gem_object *obj;
+       const u32 chunk_size = SZ_32M;
+       u32 i, offset, count, *order;
+       u64 allocated, cur_avail;
+       I915_RND_STATE(prng);
+       LIST_HEAD(objects);
+       int err = 0;
+
+       if (!list_empty(&mem->reserved)) {
+               pr_err("%s region reserved list is not empty\n", __func__);
+               return -EINVAL;
+       }
+
+       count = avail / chunk_size;
+       order = i915_random_order(count, &prng);
+       if (!order)
+               return 0;
+
+       /* Reserve a bunch of ranges within the region */
+       for (i = 0; i < count; ++i) {
+               u64 start = order[i] * chunk_size;
+               u64 size = i915_prandom_u32_max_state(chunk_size, &prng);
+
+               /* Allow for some really big holes */
+               if (!size)
+                       continue;
+
+               size = round_up(size, PAGE_SIZE);
+               offset = igt_random_offset(&prng, 0, chunk_size, size,
+                                          PAGE_SIZE);
+
+               err = intel_memory_region_reserve(mem, start + offset, size);
+               if (err) {
+                       pr_err("%s failed to reserve range", __func__);
+                       goto out_close;
+               }
+
+               /* XXX: maybe sanity check the block range here? */
+               avail -= size;
+       }
+
+       /* Try to see if we can allocate from the remaining space */
+       allocated = 0;
+       cur_avail = avail;
+       do {
+               u32 size = i915_prandom_u32_max_state(cur_avail, &prng);
+
+               size = max_t(u32, round_up(size, PAGE_SIZE), PAGE_SIZE);
+               obj = igt_object_create(mem, &objects, size, 0);
+               if (IS_ERR(obj)) {
+                       if (PTR_ERR(obj) == -ENXIO)
+                               break;
+
+                       err = PTR_ERR(obj);
+                       goto out_close;
+               }
+               cur_avail -= size;
+               allocated += size;
+       } while (1);
+
+       if (allocated != avail) {
+               pr_err("%s mismatch between allocation and free space", __func__);
+               err = -EINVAL;
+       }
+
+out_close:
+       kfree(order);
+       close_objects(mem, &objects);
+       i915_buddy_free_list(&mem->mm, &mem->reserved);
+       return err;
+}
+
 static int igt_mock_contiguous(void *arg)
 {
        struct intel_memory_region *mem = arg;
@@ -930,6 +1006,7 @@ static int perf_memcpy(void *arg)
 int intel_memory_region_mock_selftests(void)
 {
        static const struct i915_subtest tests[] = {
+               SUBTEST(igt_mock_reserve),
                SUBTEST(igt_mock_fill),
                SUBTEST(igt_mock_contiguous),
                SUBTEST(igt_mock_splintered_region),