drm/nouveau/fb: protect comptags with private mutex

nvkm_subdev.mutex is going away.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>

drivers/gpu/drm/nouveau/include/nvkm/subdev/fb.h

@@ -36,7 +36,11 @@ struct nvkm_fb {
 	struct nvkm_blob vpr_scrubber;
 
 	struct nvkm_ram *ram;
-	struct nvkm_mm tags;
+
+	struct {
+		struct mutex mutex; /* protects mm and nvkm_memory::tags */
+		struct nvkm_mm mm;
+	} tags;
 
 	struct {
 		struct nvkm_fb_tile region[16];

drivers/gpu/drm/nouveau/nvkm/core/memory.c

@@ -33,13 +33,13 @@ nvkm_memory_tags_put(struct nvkm_memory *memory, struct nvkm_device *device,
 	struct nvkm_fb *fb = device->fb;
 	struct nvkm_tags *tags = *ptags;
 	if (tags) {
-		mutex_lock(&fb->subdev.mutex);
+		mutex_lock(&fb->tags.mutex);
 		if (refcount_dec_and_test(&tags->refcount)) {
-			nvkm_mm_free(&fb->tags, &tags->mn);
+			nvkm_mm_free(&fb->tags.mm, &tags->mn);
 			kfree(memory->tags);
 			memory->tags = NULL;
 		}
-		mutex_unlock(&fb->subdev.mutex);
+		mutex_unlock(&fb->tags.mutex);
 		*ptags = NULL;
 	}
 }
@@ -52,29 +52,29 @@ nvkm_memory_tags_get(struct nvkm_memory *memory, struct nvkm_device *device,
 	struct nvkm_fb *fb = device->fb;
 	struct nvkm_tags *tags;
 
-	mutex_lock(&fb->subdev.mutex);
+	mutex_lock(&fb->tags.mutex);
 	if ((tags = memory->tags)) {
 		/* If comptags exist for the memory, but a different amount
 		 * than requested, the buffer is being mapped with settings
 		 * that are incompatible with existing mappings.
 		 */
 		if (tags->mn && tags->mn->length != nr) {
-			mutex_unlock(&fb->subdev.mutex);
+			mutex_unlock(&fb->tags.mutex);
 			return -EINVAL;
 		}
 
 		refcount_inc(&tags->refcount);
-		mutex_unlock(&fb->subdev.mutex);
+		mutex_unlock(&fb->tags.mutex);
 		*ptags = tags;
 		return 0;
 	}
 
 	if (!(tags = kmalloc(sizeof(*tags), GFP_KERNEL))) {
-		mutex_unlock(&fb->subdev.mutex);
+		mutex_unlock(&fb->tags.mutex);
 		return -ENOMEM;
 	}
 
-	if (!nvkm_mm_head(&fb->tags, 0, 1, nr, nr, 1, &tags->mn)) {
+	if (!nvkm_mm_head(&fb->tags.mm, 0, 1, nr, nr, 1, &tags->mn)) {
 		if (clr)
 			clr(device, tags->mn->offset, tags->mn->length);
 	} else {
@@ -92,7 +92,7 @@ nvkm_memory_tags_get(struct nvkm_memory *memory, struct nvkm_device *device,
 
 	refcount_set(&tags->refcount, 1);
 	*ptags = memory->tags = tags;
-	mutex_unlock(&fb->subdev.mutex);
+	mutex_unlock(&fb->tags.mutex);
 	return 0;
 }
 

drivers/gpu/drm/nouveau/nvkm/subdev/fb/base.c

@@ -122,7 +122,7 @@ nvkm_fb_oneinit(struct nvkm_subdev *subdev)
 		nvkm_debug(subdev, "%d comptags\n", tags);
 	}
 
-	return nvkm_mm_init(&fb->tags, 0, 0, tags, 1);
+	return nvkm_mm_init(&fb->tags.mm, 0, 0, tags, 1);
 }
 
 static int
@@ -205,7 +205,9 @@ nvkm_fb_dtor(struct nvkm_subdev *subdev)
 	for (i = 0; i < fb->tile.regions; i++)
 		fb->func->tile.fini(fb, i, &fb->tile.region[i]);
 
-	nvkm_mm_fini(&fb->tags);
+	nvkm_mm_fini(&fb->tags.mm);
+	mutex_destroy(&fb->tags.mutex);
+
 	nvkm_ram_del(&fb->ram);
 
 	nvkm_blob_dtor(&fb->vpr_scrubber);
@@ -230,8 +232,8 @@ nvkm_fb_ctor(const struct nvkm_fb_func *func, struct nvkm_device *device,
 	nvkm_subdev_ctor(&nvkm_fb, device, index, &fb->subdev);
 	fb->func = func;
 	fb->tile.regions = fb->func->tile.regions;
-	fb->page = nvkm_longopt(device->cfgopt, "NvFbBigPage",
-				fb->func->default_bigpage);
+	fb->page = nvkm_longopt(device->cfgopt, "NvFbBigPage", fb->func->default_bigpage);
+	mutex_init(&fb->tags.mutex);
 }
 
 int

drivers/gpu/drm/nouveau/nvkm/subdev/fb/nv20.c

@@ -45,7 +45,7 @@ nv20_fb_tile_comp(struct nvkm_fb *fb, int i, u32 size, u32 flags,
 {
 	u32 tiles = DIV_ROUND_UP(size, 0x40);
 	u32 tags  = round_up(tiles / fb->ram->parts, 0x40);
-	if (!nvkm_mm_head(&fb->tags, 0, 1, tags, tags, 1, &tile->tag)) {
+	if (!nvkm_mm_head(&fb->tags.mm, 0, 1, tags, tags, 1, &tile->tag)) {
 		if (!(flags & 2)) tile->zcomp = 0x00000000; /* Z16 */
 		else              tile->zcomp = 0x04000000; /* Z24S8 */
 		tile->zcomp |= tile->tag->offset;
@@ -63,7 +63,7 @@ nv20_fb_tile_fini(struct nvkm_fb *fb, int i, struct nvkm_fb_tile *tile)
 	tile->limit = 0;
 	tile->pitch = 0;
 	tile->zcomp = 0;
-	nvkm_mm_free(&fb->tags, &tile->tag);
+	nvkm_mm_free(&fb->tags.mm, &tile->tag);
 }
 
 void

drivers/gpu/drm/nouveau/nvkm/subdev/fb/nv25.c

@@ -32,7 +32,7 @@ nv25_fb_tile_comp(struct nvkm_fb *fb, int i, u32 size, u32 flags,
 {
 	u32 tiles = DIV_ROUND_UP(size, 0x40);
 	u32 tags  = round_up(tiles / fb->ram->parts, 0x40);
-	if (!nvkm_mm_head(&fb->tags, 0, 1, tags, tags, 1, &tile->tag)) {
+	if (!nvkm_mm_head(&fb->tags.mm, 0, 1, tags, tags, 1, &tile->tag)) {
 		if (!(flags & 2)) tile->zcomp = 0x00100000; /* Z16 */
 		else              tile->zcomp = 0x00200000; /* Z24S8 */
 		tile->zcomp |= tile->tag->offset;

drivers/gpu/drm/nouveau/nvkm/subdev/fb/nv30.c

@@ -51,7 +51,7 @@ nv30_fb_tile_comp(struct nvkm_fb *fb, int i, u32 size, u32 flags,
 {
 	u32 tiles = DIV_ROUND_UP(size, 0x40);
 	u32 tags  = round_up(tiles / fb->ram->parts, 0x40);
-	if (!nvkm_mm_head(&fb->tags, 0, 1, tags, tags, 1, &tile->tag)) {
+	if (!nvkm_mm_head(&fb->tags.mm, 0, 1, tags, tags, 1, &tile->tag)) {
 		if (flags & 2) tile->zcomp |= 0x01000000; /* Z16 */
 		else           tile->zcomp |= 0x02000000; /* Z24S8 */
 		tile->zcomp |= ((tile->tag->offset           ) >> 6);

drivers/gpu/drm/nouveau/nvkm/subdev/fb/nv35.c

@@ -32,7 +32,7 @@ nv35_fb_tile_comp(struct nvkm_fb *fb, int i, u32 size, u32 flags,
 {
 	u32 tiles = DIV_ROUND_UP(size, 0x40);
 	u32 tags  = round_up(tiles / fb->ram->parts, 0x40);
-	if (!nvkm_mm_head(&fb->tags, 0, 1, tags, tags, 1, &tile->tag)) {
+	if (!nvkm_mm_head(&fb->tags.mm, 0, 1, tags, tags, 1, &tile->tag)) {
 		if (flags & 2) tile->zcomp |= 0x04000000; /* Z16 */
 		else           tile->zcomp |= 0x08000000; /* Z24S8 */
 		tile->zcomp |= ((tile->tag->offset           ) >> 6);

drivers/gpu/drm/nouveau/nvkm/subdev/fb/nv36.c

@@ -32,7 +32,7 @@ nv36_fb_tile_comp(struct nvkm_fb *fb, int i, u32 size, u32 flags,
 {
 	u32 tiles = DIV_ROUND_UP(size, 0x40);
 	u32 tags  = round_up(tiles / fb->ram->parts, 0x40);
-	if (!nvkm_mm_head(&fb->tags, 0, 1, tags, tags, 1, &tile->tag)) {
+	if (!nvkm_mm_head(&fb->tags.mm, 0, 1, tags, tags, 1, &tile->tag)) {
 		if (flags & 2) tile->zcomp |= 0x10000000; /* Z16 */
 		else           tile->zcomp |= 0x20000000; /* Z24S8 */
 		tile->zcomp |= ((tile->tag->offset           ) >> 6);

drivers/gpu/drm/nouveau/nvkm/subdev/fb/nv40.c

@@ -33,7 +33,7 @@ nv40_fb_tile_comp(struct nvkm_fb *fb, int i, u32 size, u32 flags,
 	u32 tiles = DIV_ROUND_UP(size, 0x80);
 	u32 tags  = round_up(tiles / fb->ram->parts, 0x100);
 	if ( (flags & 2) &&
-	    !nvkm_mm_head(&fb->tags, 0, 1, tags, tags, 1, &tile->tag)) {
+	    !nvkm_mm_head(&fb->tags.mm, 0, 1, tags, tags, 1, &tile->tag)) {
 		tile->zcomp  = 0x28000000; /* Z24S8_SPLIT_GRAD */
 		tile->zcomp |= ((tile->tag->offset           ) >> 8);
 		tile->zcomp |= ((tile->tag->offset + tags - 1) >> 8) << 13;

drivers/gpu/drm/nouveau/nvkm/subdev/ltc/gf100.c

@@ -200,8 +200,8 @@ gf100_ltc_oneinit_tag_ram(struct nvkm_ltc *ltc)
 	}
 
 mm_init:
-	nvkm_mm_fini(&fb->tags);
-	return nvkm_mm_init(&fb->tags, 0, 0, ltc->num_tags, 1);
+	nvkm_mm_fini(&fb->tags.mm);
+	return nvkm_mm_init(&fb->tags.mm, 0, 0, ltc->num_tags, 1);
 }
 
 int