drm/udl: Move vmap out of commit tail

Vmap operations may acquire the dmabuf reservation lock, which is not
allowed within atomic commit-tail functions. Therefore move vmap and
vunmap from the damage handler into prepare_fb and cleanup_fb callbacks.

The mapping is provided as GEM shadow-buffered plane. The functions in
the commit tail use the pre-established mapping for damage handling.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210208115538.6430-8-tzimmermann@suse.de

diff --git a/drivers/gpu/drm/udl/udl_modeset.c b/drivers/gpu/drm/udl/udl_modeset.c
index 9d34ec9..8d98bf6 100644 (file)
--- a/drivers/gpu/drm/udl/udl_modeset.c
+++ b/drivers/gpu/drm/udl/udl_modeset.c
@@ -15,6 +15,7 @@
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_damage_helper.h>
 #include <drm/drm_fourcc.h>
+#include <drm/drm_gem_atomic_helper.h>
 #include <drm/drm_gem_framebuffer_helper.h>
 #include <drm/drm_gem_shmem_helper.h>
 #include <drm/drm_modeset_helper_vtables.h>
@@ -266,18 +267,17 @@ static int udl_aligned_damage_clip(struct drm_rect *clip, int x, int y,
        return 0;
 }
 
-static int udl_handle_damage(struct drm_framebuffer *fb, int x, int y,
-                            int width, int height)
+static int udl_handle_damage(struct drm_framebuffer *fb, const struct dma_buf_map *map,
+                            int x, int y, int width, int height)
 {
        struct drm_device *dev = fb->dev;
        struct dma_buf_attachment *import_attach = fb->obj[0]->import_attach;
+       void *vaddr = map->vaddr; /* TODO: Use mapping abstraction properly */
        int i, ret, tmp_ret;
        char *cmd;
        struct urb *urb;
        struct drm_rect clip;
        int log_bpp;
-       struct dma_buf_map map;
-       void *vaddr;
 
        ret = udl_log_cpp(fb->format->cpp[0]);
        if (ret < 0)
@@ -297,17 +297,10 @@ static int udl_handle_damage(struct drm_framebuffer *fb, int x, int y,
                        return ret;
        }
 
-       ret = drm_gem_shmem_vmap(fb->obj[0], &map);
-       if (ret) {
-               DRM_ERROR("failed to vmap fb\n");
-               goto out_dma_buf_end_cpu_access;
-       }
-       vaddr = map.vaddr; /* TODO: Use mapping abstraction properly */
-
        urb = udl_get_urb(dev);
        if (!urb) {
                ret = -ENOMEM;
-               goto out_drm_gem_shmem_vunmap;
+               goto out_dma_buf_end_cpu_access;
        }
        cmd = urb->transfer_buffer;
 
@@ -320,7 +313,7 @@ static int udl_handle_damage(struct drm_framebuffer *fb, int x, int y,
                                       &cmd, byte_offset, dev_byte_offset,
                                       byte_width);
                if (ret)
-                       goto out_drm_gem_shmem_vunmap;
+                       goto out_dma_buf_end_cpu_access;
        }
 
        if (cmd > (char *)urb->transfer_buffer) {
@@ -336,8 +329,6 @@ static int udl_handle_damage(struct drm_framebuffer *fb, int x, int y,
 
        ret = 0;
 
-out_drm_gem_shmem_vunmap:
-       drm_gem_shmem_vunmap(fb->obj[0], &map);
 out_dma_buf_end_cpu_access:
        if (import_attach) {
                tmp_ret = dma_buf_end_cpu_access(import_attach->dmabuf,
@@ -375,6 +366,7 @@ udl_simple_display_pipe_enable(struct drm_simple_display_pipe *pipe,
        struct drm_framebuffer *fb = plane_state->fb;
        struct udl_device *udl = to_udl(dev);
        struct drm_display_mode *mode = &crtc_state->mode;
+       struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
        char *buf;
        char *wrptr;
        int color_depth = UDL_COLOR_DEPTH_16BPP;
@@ -400,7 +392,7 @@ udl_simple_display_pipe_enable(struct drm_simple_display_pipe *pipe,
 
        udl->mode_buf_len = wrptr - buf;
 
-       udl_handle_damage(fb, 0, 0, fb->width, fb->height);
+       udl_handle_damage(fb, &shadow_plane_state->map[0], 0, 0, fb->width, fb->height);
 
        if (!crtc_state->mode_changed)
                return;
@@ -435,6 +427,7 @@ udl_simple_display_pipe_update(struct drm_simple_display_pipe *pipe,
                               struct drm_plane_state *old_plane_state)
 {
        struct drm_plane_state *state = pipe->plane.state;
+       struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(state);
        struct drm_framebuffer *fb = state->fb;
        struct drm_rect rect;
 
@@ -442,17 +435,16 @@ udl_simple_display_pipe_update(struct drm_simple_display_pipe *pipe,
                return;
 
        if (drm_atomic_helper_damage_merged(old_plane_state, state, &rect))
-               udl_handle_damage(fb, rect.x1, rect.y1, rect.x2 - rect.x1,
-                                 rect.y2 - rect.y1);
+               udl_handle_damage(fb, &shadow_plane_state->map[0], rect.x1, rect.y1,
+                                 rect.x2 - rect.x1, rect.y2 - rect.y1);
 }
 
-static const
-struct drm_simple_display_pipe_funcs udl_simple_display_pipe_funcs = {
+static const struct drm_simple_display_pipe_funcs udl_simple_display_pipe_funcs = {
        .mode_valid = udl_simple_display_pipe_mode_valid,
        .enable = udl_simple_display_pipe_enable,
        .disable = udl_simple_display_pipe_disable,
        .update = udl_simple_display_pipe_update,
-       .prepare_fb = drm_gem_fb_simple_display_pipe_prepare_fb,
+       DRM_GEM_SIMPLE_DISPLAY_PIPE_SHADOW_PLANE_FUNCS,
 };
 
 /*