From a85955568939e20e573cf42095d90c8476c9cec1 Mon Sep 17 00:00:00 2001 From: Thomas Zimmermann Date: Tue, 3 Nov 2020 10:30:13 +0100 Subject: [PATCH] drm/gem: Store client buffer mappings as struct dma_buf_map Kernel DRM clients now store their framebuffer address in an instance of struct dma_buf_map. Depending on the buffer's location, the address refers to system or I/O memory. Callers of drm_client_buffer_vmap() receive a copy of the value in the call's supplied arguments. It can be accessed and modified with dma_buf_map interfaces. v6: * don't call page_to_phys() on framebuffers in I/O memory; warn instead (Daniel) Signed-off-by: Thomas Zimmermann Reviewed-by: Daniel Vetter Tested-by: Sam Ravnborg Link: https://patchwork.freedesktop.org/patch/msgid/20201103093015.1063-9-tzimmermann@suse.de --- drivers/gpu/drm/drm_client.c | 34 +++++++++++++++++++-------------- drivers/gpu/drm/drm_fb_helper.c | 32 ++++++++++++++++++++----------- include/drm/drm_client.h | 7 ++++--- 3 files changed, 45 insertions(+), 28 deletions(-) diff --git a/drivers/gpu/drm/drm_client.c b/drivers/gpu/drm/drm_client.c index ac0082bed966..fe573acf1067 100644 --- a/drivers/gpu/drm/drm_client.c +++ b/drivers/gpu/drm/drm_client.c @@ -235,7 +235,7 @@ static void drm_client_buffer_delete(struct drm_client_buffer *buffer) { struct drm_device *dev = buffer->client->dev; - drm_gem_vunmap(buffer->gem, buffer->vaddr); + drm_gem_vunmap(buffer->gem, &buffer->map); if (buffer->gem) drm_gem_object_put(buffer->gem); @@ -291,25 +291,31 @@ err_delete: /** * drm_client_buffer_vmap - Map DRM client buffer into address space * @buffer: DRM client buffer + * @map_copy: Returns the mapped memory's address * * This function maps a client buffer into kernel address space. If the - * buffer is already mapped, it returns the mapping's address. + * buffer is already mapped, it returns the existing mapping's address. * * Client buffer mappings are not ref'counted. Each call to * drm_client_buffer_vmap() should be followed by a call to * drm_client_buffer_vunmap(); or the client buffer should be mapped * throughout its lifetime. * + * The returned address is a copy of the internal value. In contrast to + * other vmap interfaces, you don't need it for the client's vunmap + * function. So you can modify it at will during blit and draw operations. + * * Returns: - * The mapped memory's address + * 0 on success, or a negative errno code otherwise. */ -void *drm_client_buffer_vmap(struct drm_client_buffer *buffer) +int +drm_client_buffer_vmap(struct drm_client_buffer *buffer, struct dma_buf_map *map_copy) { - struct dma_buf_map map; + struct dma_buf_map *map = &buffer->map; int ret; - if (buffer->vaddr) - return buffer->vaddr; + if (dma_buf_map_is_set(map)) + goto out; /* * FIXME: The dependency on GEM here isn't required, we could @@ -319,13 +325,14 @@ void *drm_client_buffer_vmap(struct drm_client_buffer *buffer) * fd_install step out of the driver backend hooks, to make that * final step optional for internal users. */ - ret = drm_gem_vmap(buffer->gem, &map); + ret = drm_gem_vmap(buffer->gem, map); if (ret) - return ERR_PTR(ret); + return ret; - buffer->vaddr = map.vaddr; +out: + *map_copy = *map; - return map.vaddr; + return 0; } EXPORT_SYMBOL(drm_client_buffer_vmap); @@ -339,10 +346,9 @@ EXPORT_SYMBOL(drm_client_buffer_vmap); */ void drm_client_buffer_vunmap(struct drm_client_buffer *buffer) { - struct dma_buf_map map = DMA_BUF_MAP_INIT_VADDR(buffer->vaddr); + struct dma_buf_map *map = &buffer->map; - drm_gem_vunmap(buffer->gem, &map); - buffer->vaddr = NULL; + drm_gem_vunmap(buffer->gem, map); } EXPORT_SYMBOL(drm_client_buffer_vunmap); diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 92e0db30fdf7..a0d88130fedb 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -378,7 +378,7 @@ static void drm_fb_helper_dirty_blit_real(struct drm_fb_helper *fb_helper, unsigned int cpp = fb->format->cpp[0]; size_t offset = clip->y1 * fb->pitches[0] + clip->x1 * cpp; void *src = fb_helper->fbdev->screen_buffer + offset; - void *dst = fb_helper->buffer->vaddr + offset; + void *dst = fb_helper->buffer->map.vaddr + offset; size_t len = (clip->x2 - clip->x1) * cpp; unsigned int y; @@ -400,7 +400,8 @@ static void drm_fb_helper_dirty_work(struct work_struct *work) struct drm_clip_rect *clip = &helper->dirty_clip; struct drm_clip_rect clip_copy; unsigned long flags; - void *vaddr; + struct dma_buf_map map; + int ret; spin_lock_irqsave(&helper->dirty_lock, flags); clip_copy = *clip; @@ -413,8 +414,8 @@ static void drm_fb_helper_dirty_work(struct work_struct *work) /* Generic fbdev uses a shadow buffer */ if (helper->buffer) { - vaddr = drm_client_buffer_vmap(helper->buffer); - if (IS_ERR(vaddr)) + ret = drm_client_buffer_vmap(helper->buffer, &map); + if (ret) return; drm_fb_helper_dirty_blit_real(helper, &clip_copy); } @@ -2060,7 +2061,8 @@ static int drm_fb_helper_generic_probe(struct drm_fb_helper *fb_helper, struct drm_framebuffer *fb; struct fb_info *fbi; u32 format; - void *vaddr; + struct dma_buf_map map; + int ret; drm_dbg_kms(dev, "surface width(%d), height(%d) and bpp(%d)\n", sizes->surface_width, sizes->surface_height, @@ -2096,14 +2098,22 @@ static int drm_fb_helper_generic_probe(struct drm_fb_helper *fb_helper, fb_deferred_io_init(fbi); } else { /* buffer is mapped for HW framebuffer */ - vaddr = drm_client_buffer_vmap(fb_helper->buffer); - if (IS_ERR(vaddr)) - return PTR_ERR(vaddr); + ret = drm_client_buffer_vmap(fb_helper->buffer, &map); + if (ret) + return ret; + if (map.is_iomem) + fbi->screen_base = map.vaddr_iomem; + else + fbi->screen_buffer = map.vaddr; - fbi->screen_buffer = vaddr; - /* Shamelessly leak the physical address to user-space */ + /* + * Shamelessly leak the physical address to user-space. As + * page_to_phys() is undefined for I/O memory, warn in this + * case. + */ #if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM) - if (drm_leak_fbdev_smem && fbi->fix.smem_start == 0) + if (drm_leak_fbdev_smem && fbi->fix.smem_start == 0 && + !drm_WARN_ON_ONCE(dev, map.is_iomem)) fbi->fix.smem_start = page_to_phys(virt_to_page(fbi->screen_buffer)); #endif diff --git a/include/drm/drm_client.h b/include/drm/drm_client.h index 7aaea665bfc2..f07f2fb02e75 100644 --- a/include/drm/drm_client.h +++ b/include/drm/drm_client.h @@ -3,6 +3,7 @@ #ifndef _DRM_CLIENT_H_ #define _DRM_CLIENT_H_ +#include #include #include #include @@ -141,9 +142,9 @@ struct drm_client_buffer { struct drm_gem_object *gem; /** - * @vaddr: Virtual address for the buffer + * @map: Virtual address for the buffer */ - void *vaddr; + struct dma_buf_map map; /** * @fb: DRM framebuffer @@ -155,7 +156,7 @@ struct drm_client_buffer * drm_client_framebuffer_create(struct drm_client_dev *client, u32 width, u32 height, u32 format); void drm_client_framebuffer_delete(struct drm_client_buffer *buffer); int drm_client_framebuffer_flush(struct drm_client_buffer *buffer, struct drm_rect *rect); -void *drm_client_buffer_vmap(struct drm_client_buffer *buffer); +int drm_client_buffer_vmap(struct drm_client_buffer *buffer, struct dma_buf_map *map); void drm_client_buffer_vunmap(struct drm_client_buffer *buffer); int drm_client_modeset_create(struct drm_client_dev *client); -- 2.34.1