Thomas Zimmermann
2023-Mar-20 15:07 UTC
[PATCH v2 0/8] drm/fbdev-generic: Mandatory shadow buffering
After adding fbdev-dma and converting drivers, all users of fbdev-generic require shadow buffering. Make it mandatory and remove all other codepaths. This change greatly simplifies the code for generic fbdev emulation. It will work with any driver that supports GEM's vmap and vunmap. The change further allows for a number of cleanups and fixes. The flag prefer_shadow_fbdev is unused and to be removed. Probing in fbdev-generic is now simple enough to roll back if it fails. Further simplify the code for exporting the framebuffer's physical address. Finally rename the symbols to follow other fbdev emulation. v2: * handle screen_size in separate patches (Javier) Thomas Zimmermann (8): drm/fbdev-generic: Always use shadow buffering drm/fbdev-generic: Remove unused prefer_shadow_fbdev flag drm/fb-helper: Export drm_fb_helper_release_info() drm/fb-helper: Support smem_len in deferred I/O drm/fbdev-generic: Set screen size to size of GEM buffer drm/fbdev-generic: Clean up after failed probing drm/fb-helper: Consolidate CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM drm/fbdev-generic: Rename symbols drivers/gpu/drm/drm_fb_helper.c | 63 ++++--- drivers/gpu/drm/drm_fbdev_dma.c | 9 +- drivers/gpu/drm/drm_fbdev_generic.c | 279 +++++++++------------------- drivers/gpu/drm/tiny/bochs.c | 1 - drivers/gpu/drm/vmwgfx/vmwgfx_kms.c | 1 - include/drm/drm_fb_helper.h | 14 +- include/drm/drm_mode_config.h | 7 - 7 files changed, 130 insertions(+), 244 deletions(-) base-commit: 3333280906872bb8c2dff02666c7a8e46f085b24 -- 2.40.0
Thomas Zimmermann
2023-Mar-20 15:07 UTC
[PATCH v2 1/8] drm/fbdev-generic: Always use shadow buffering
Remove all codepaths that implement fbdev output directly on GEM
buffers. Always allocate a shadow buffer in system memory and set
up deferred I/O for mmap.
The fbdev code that operated directly on GEM buffers was used by
drivers based on GEM DMA helpers. Those drivers have been migrated
to use fbdev-dma, a dedicated fbdev emulation for DMA memory. All
remaining users of fbdev-generic require shadow buffering.
Memory management of the remaining callers uses TTM, GEM SHMEM
helpers or a variant of GEM DMA helpers that is incompatible with
fbdev-dma. Therefore remove the unused codepaths from fbdev-generic
and simplify the code.
Using a shadow buffer with deferred I/O is probably the best case
for most remaining callers. Some of the TTM-based drivers might
benefit from a dedicated fbdev emulation that operates directly on
the driver's video memory.
Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
Reviewed-by: Javier Martinez Canillas <javierm at redhat.com>
Acked-by: Zack Rusin <zackr at vmware.com>
---
drivers/gpu/drm/drm_fbdev_generic.c | 184 +++++-----------------------
1 file changed, 30 insertions(+), 154 deletions(-)
diff --git a/drivers/gpu/drm/drm_fbdev_generic.c
b/drivers/gpu/drm/drm_fbdev_generic.c
index 4d6325e91565..e48a8e82378d 100644
--- a/drivers/gpu/drm/drm_fbdev_generic.c
+++ b/drivers/gpu/drm/drm_fbdev_generic.c
@@ -11,16 +11,6 @@
#include <drm/drm_fbdev_generic.h>
-static bool drm_fbdev_use_shadow_fb(struct drm_fb_helper *fb_helper)
-{
- struct drm_device *dev = fb_helper->dev;
- struct drm_framebuffer *fb = fb_helper->fb;
-
- return dev->mode_config.prefer_shadow_fbdev ||
- dev->mode_config.prefer_shadow ||
- fb->funcs->dirty;
-}
-
/* @user: 1=userspace, 0=fbcon */
static int drm_fbdev_fb_open(struct fb_info *info, int user)
{
@@ -46,115 +36,33 @@ static int drm_fbdev_fb_release(struct fb_info *info, int
user)
static void drm_fbdev_fb_destroy(struct fb_info *info)
{
struct drm_fb_helper *fb_helper = info->par;
- void *shadow = NULL;
+ void *shadow = info->screen_buffer;
if (!fb_helper->dev)
return;
- if (info->fbdefio)
- fb_deferred_io_cleanup(info);
- if (drm_fbdev_use_shadow_fb(fb_helper))
- shadow = info->screen_buffer;
-
+ fb_deferred_io_cleanup(info);
drm_fb_helper_fini(fb_helper);
-
- if (shadow)
- vfree(shadow);
- else if (fb_helper->buffer)
- drm_client_buffer_vunmap(fb_helper->buffer);
-
+ vfree(shadow);
drm_client_framebuffer_delete(fb_helper->buffer);
- drm_client_release(&fb_helper->client);
+ drm_client_release(&fb_helper->client);
drm_fb_helper_unprepare(fb_helper);
kfree(fb_helper);
}
-static int drm_fbdev_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
-{
- struct drm_fb_helper *fb_helper = info->par;
-
- if (drm_fbdev_use_shadow_fb(fb_helper))
- return fb_deferred_io_mmap(info, vma);
- else if (fb_helper->dev->driver->gem_prime_mmap)
- return
fb_helper->dev->driver->gem_prime_mmap(fb_helper->buffer->gem,
vma);
- else
- return -ENODEV;
-}
-
-static bool drm_fbdev_use_iomem(struct fb_info *info)
-{
- struct drm_fb_helper *fb_helper = info->par;
- struct drm_client_buffer *buffer = fb_helper->buffer;
-
- return !drm_fbdev_use_shadow_fb(fb_helper) && buffer->map.is_iomem;
-}
-
-static ssize_t drm_fbdev_fb_read(struct fb_info *info, char __user *buf,
- size_t count, loff_t *ppos)
-{
- ssize_t ret;
-
- if (drm_fbdev_use_iomem(info))
- ret = drm_fb_helper_cfb_read(info, buf, count, ppos);
- else
- ret = drm_fb_helper_sys_read(info, buf, count, ppos);
-
- return ret;
-}
-
-static ssize_t drm_fbdev_fb_write(struct fb_info *info, const char __user *buf,
- size_t count, loff_t *ppos)
-{
- ssize_t ret;
-
- if (drm_fbdev_use_iomem(info))
- ret = drm_fb_helper_cfb_write(info, buf, count, ppos);
- else
- ret = drm_fb_helper_sys_write(info, buf, count, ppos);
-
- return ret;
-}
-
-static void drm_fbdev_fb_fillrect(struct fb_info *info,
- const struct fb_fillrect *rect)
-{
- if (drm_fbdev_use_iomem(info))
- drm_fb_helper_cfb_fillrect(info, rect);
- else
- drm_fb_helper_sys_fillrect(info, rect);
-}
-
-static void drm_fbdev_fb_copyarea(struct fb_info *info,
- const struct fb_copyarea *area)
-{
- if (drm_fbdev_use_iomem(info))
- drm_fb_helper_cfb_copyarea(info, area);
- else
- drm_fb_helper_sys_copyarea(info, area);
-}
-
-static void drm_fbdev_fb_imageblit(struct fb_info *info,
- const struct fb_image *image)
-{
- if (drm_fbdev_use_iomem(info))
- drm_fb_helper_cfb_imageblit(info, image);
- else
- drm_fb_helper_sys_imageblit(info, image);
-}
-
static const struct fb_ops drm_fbdev_fb_ops = {
.owner = THIS_MODULE,
- DRM_FB_HELPER_DEFAULT_OPS,
.fb_open = drm_fbdev_fb_open,
.fb_release = drm_fbdev_fb_release,
+ .fb_read = drm_fb_helper_sys_read,
+ .fb_write = drm_fb_helper_sys_write,
+ DRM_FB_HELPER_DEFAULT_OPS,
+ .fb_fillrect = drm_fb_helper_sys_fillrect,
+ .fb_copyarea = drm_fb_helper_sys_copyarea,
+ .fb_imageblit = drm_fb_helper_sys_imageblit,
+ .fb_mmap = fb_deferred_io_mmap,
.fb_destroy = drm_fbdev_fb_destroy,
- .fb_mmap = drm_fbdev_fb_mmap,
- .fb_read = drm_fbdev_fb_read,
- .fb_write = drm_fbdev_fb_write,
- .fb_fillrect = drm_fbdev_fb_fillrect,
- .fb_copyarea = drm_fbdev_fb_copyarea,
- .fb_imageblit = drm_fbdev_fb_imageblit,
};
/*
@@ -169,7 +77,6 @@ static int drm_fbdev_fb_probe(struct drm_fb_helper
*fb_helper,
struct drm_framebuffer *fb;
struct fb_info *info;
u32 format;
- struct iosys_map map;
int ret;
drm_dbg_kms(dev, "surface width(%d), height(%d) and bpp(%d)\n",
@@ -197,44 +104,21 @@ static int drm_fbdev_fb_probe(struct drm_fb_helper
*fb_helper,
drm_fb_helper_fill_info(info, fb_helper, sizes);
- if (drm_fbdev_use_shadow_fb(fb_helper)) {
- info->screen_buffer = vzalloc(info->screen_size);
- if (!info->screen_buffer)
- return -ENOMEM;
- info->flags |= FBINFO_VIRTFB | FBINFO_READS_FAST;
+ info->screen_buffer = vzalloc(info->screen_size);
+ if (!info->screen_buffer)
+ return -ENOMEM;
+ info->flags |= FBINFO_VIRTFB | FBINFO_READS_FAST;
- /* Set a default deferred I/O handler */
- fb_helper->fbdefio.delay = HZ / 20;
- fb_helper->fbdefio.deferred_io = drm_fb_helper_deferred_io;
+ info->fix.smem_start =
page_to_phys(vmalloc_to_page(info->screen_buffer));
- info->fbdefio = &fb_helper->fbdefio;
- ret = fb_deferred_io_init(info);
- if (ret)
- return ret;
- } else {
- /* buffer is mapped for HW framebuffer */
- ret = drm_client_buffer_vmap(fb_helper->buffer, &map);
- if (ret)
- return ret;
- if (map.is_iomem) {
- info->screen_base = map.vaddr_iomem;
- } else {
- info->screen_buffer = map.vaddr;
- info->flags |= FBINFO_VIRTFB;
- }
-
- /*
- * 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 (fb_helper->hint_leak_smem_start && info->fix.smem_start ==
0 &&
- !drm_WARN_ON_ONCE(dev, map.is_iomem))
- info->fix.smem_start -
page_to_phys(virt_to_page(info->screen_buffer));
-#endif
- }
+ /* Set a default deferred I/O handler */
+ fb_helper->fbdefio.delay = HZ / 20;
+ fb_helper->fbdefio.deferred_io = drm_fb_helper_deferred_io;
+
+ info->fbdefio = &fb_helper->fbdefio;
+ ret = fb_deferred_io_init(info);
+ if (ret)
+ return ret;
return 0;
}
@@ -318,18 +202,13 @@ static int drm_fbdev_fb_dirty(struct drm_fb_helper
*helper, struct drm_clip_rect
struct drm_device *dev = helper->dev;
int ret;
- if (!drm_fbdev_use_shadow_fb(helper))
- return 0;
-
/* Call damage handlers only if necessary */
if (!(clip->x1 < clip->x2 && clip->y1 < clip->y2))
return 0;
- if (helper->buffer) {
- ret = drm_fbdev_damage_blit(helper, clip);
- if (drm_WARN_ONCE(dev, ret, "Damage blitter failed: ret=%d\n",
ret))
- return ret;
- }
+ ret = drm_fbdev_damage_blit(helper, clip);
+ if (drm_WARN_ONCE(dev, ret, "Damage blitter failed: ret=%d\n", ret))
+ return ret;
if (helper->fb->funcs->dirty) {
ret = helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, clip, 1);
@@ -415,12 +294,9 @@ static const struct drm_client_funcs drm_fbdev_client_funcs
= {
* suspend/resume need to call drm_fb_helper_set_suspend_unlocked() themselves.
* Simple drivers might use drm_mode_config_helper_suspend().
*
- * Drivers that set the dirty callback on their framebuffer will get a shadow
- * fbdev buffer that is blitted onto the real buffer. This is done in order to
- * make deferred I/O work with all kinds of buffers. A shadow buffer can be
- * requested explicitly by setting struct drm_mode_config.prefer_shadow or
- * struct drm_mode_config.prefer_shadow_fbdev to true beforehand. This is
- * required to use generic fbdev emulation with SHMEM helpers.
+ * In order to provide fixed mmap-able memory ranges, generic fbdev emulation
+ * uses a shadow buffer in system memory. The implementation blits the shadow
+ * fbdev buffer onto the real buffer in regular intervals.
*
* This function is safe to call even when there are no connectors present.
* Setup will be retried on the next hotplug event.
--
2.40.0
Thomas Zimmermann
2023-Mar-20 15:07 UTC
[PATCH v2 2/8] drm/fbdev-generic: Remove unused prefer_shadow_fbdev flag
Remove the flag prefer_shadow_fbdev from struct drm_mode_config.
Drivers set this flag to enable shadow buffering in the generic
fbdev emulation. Such shadow buffering is now mandatory, so the
flag is unused.
Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
Reviewed-by: Javier Martinez Canillas <javierm at redhat.com>
Reviewed-by: Zack Rusin <zackr at vmware.com>
---
drivers/gpu/drm/tiny/bochs.c | 1 -
drivers/gpu/drm/vmwgfx/vmwgfx_kms.c | 1 -
include/drm/drm_mode_config.h | 7 -------
3 files changed, 9 deletions(-)
diff --git a/drivers/gpu/drm/tiny/bochs.c b/drivers/gpu/drm/tiny/bochs.c
index 024346054c70..d254679a136e 100644
--- a/drivers/gpu/drm/tiny/bochs.c
+++ b/drivers/gpu/drm/tiny/bochs.c
@@ -545,7 +545,6 @@ static int bochs_kms_init(struct bochs_device *bochs)
bochs->dev->mode_config.preferred_depth = 24;
bochs->dev->mode_config.prefer_shadow = 0;
- bochs->dev->mode_config.prefer_shadow_fbdev = 1;
bochs->dev->mode_config.quirk_addfb_prefer_host_byte_order = true;
bochs->dev->mode_config.funcs = &bochs_mode_funcs;
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
index 84d6380b9895..5162a7a12792 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
@@ -2112,7 +2112,6 @@ int vmw_kms_init(struct vmw_private *dev_priv)
dev->mode_config.max_width = dev_priv->texture_max_width;
dev->mode_config.max_height = dev_priv->texture_max_height;
dev->mode_config.preferred_depth = dev_priv->assume_16bpp ? 16 : 32;
- dev->mode_config.prefer_shadow_fbdev = !dev_priv->has_mob;
drm_mode_create_suggested_offset_properties(dev);
vmw_kms_create_hotplug_mode_update_property(dev_priv);
diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h
index e5b053001d22..973119a9176b 100644
--- a/include/drm/drm_mode_config.h
+++ b/include/drm/drm_mode_config.h
@@ -890,13 +890,6 @@ struct drm_mode_config {
/* dumb ioctl parameters */
uint32_t preferred_depth, prefer_shadow;
- /**
- * @prefer_shadow_fbdev:
- *
- * Hint to framebuffer emulation to prefer shadow-fb rendering.
- */
- bool prefer_shadow_fbdev;
-
/**
* @quirk_addfb_prefer_xbgr_30bpp:
*
--
2.40.0
Thomas Zimmermann
2023-Mar-20 15:07 UTC
[PATCH v2 3/8] drm/fb-helper: Export drm_fb_helper_release_info()
Export the fb_info release code as drm_fb_helper_release_info(). Will
help with cleaning up failed fbdev probing.
Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
Reviewed-by: Javier Martinez Canillas <javierm at redhat.com>
Acked-by: Zack Rusin <zackr at vmware.com>
---
drivers/gpu/drm/drm_fb_helper.c | 33 ++++++++++++++++++++++++---------
include/drm/drm_fb_helper.h | 5 +++++
2 files changed, 29 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index a39998047f8a..7e96ed9efdb5 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -538,6 +538,29 @@ struct fb_info *drm_fb_helper_alloc_info(struct
drm_fb_helper *fb_helper)
}
EXPORT_SYMBOL(drm_fb_helper_alloc_info);
+/**
+ * drm_fb_helper_release_info - release fb_info and its members
+ * @fb_helper: driver-allocated fbdev helper
+ *
+ * A helper to release fb_info and the member cmap. Drivers do not
+ * need to release the allocated fb_info structure themselves, this is
+ * automatically done when calling drm_fb_helper_fini().
+ */
+void drm_fb_helper_release_info(struct drm_fb_helper *fb_helper)
+{
+ struct fb_info *info = fb_helper->info;
+
+ if (!info)
+ return;
+
+ fb_helper->info = NULL;
+
+ if (info->cmap.len)
+ fb_dealloc_cmap(&info->cmap);
+ framebuffer_release(info);
+}
+EXPORT_SYMBOL(drm_fb_helper_release_info);
+
/**
* drm_fb_helper_unregister_info - unregister fb_info framebuffer device
* @fb_helper: driver-allocated fbdev helper, can be NULL
@@ -561,8 +584,6 @@ EXPORT_SYMBOL(drm_fb_helper_unregister_info);
*/
void drm_fb_helper_fini(struct drm_fb_helper *fb_helper)
{
- struct fb_info *info;
-
if (!fb_helper)
return;
@@ -574,13 +595,7 @@ void drm_fb_helper_fini(struct drm_fb_helper *fb_helper)
cancel_work_sync(&fb_helper->resume_work);
cancel_work_sync(&fb_helper->damage_work);
- info = fb_helper->info;
- if (info) {
- if (info->cmap.len)
- fb_dealloc_cmap(&info->cmap);
- framebuffer_release(info);
- }
- fb_helper->info = NULL;
+ drm_fb_helper_release_info(fb_helper);
mutex_lock(&kernel_fb_helper_lock);
if (!list_empty(&fb_helper->kernel_fb_list)) {
diff --git a/include/drm/drm_fb_helper.h b/include/drm/drm_fb_helper.h
index 013654de3fc5..c5822ec2fdd1 100644
--- a/include/drm/drm_fb_helper.h
+++ b/include/drm/drm_fb_helper.h
@@ -256,6 +256,7 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper);
struct fb_info *drm_fb_helper_alloc_info(struct drm_fb_helper *fb_helper);
+void drm_fb_helper_release_info(struct drm_fb_helper *fb_helper);
void drm_fb_helper_unregister_info(struct drm_fb_helper *fb_helper);
void drm_fb_helper_fill_info(struct fb_info *info,
struct drm_fb_helper *fb_helper,
@@ -365,6 +366,10 @@ drm_fb_helper_alloc_info(struct drm_fb_helper *fb_helper)
return NULL;
}
+static inline void drm_fb_helper_release_info(struct drm_fb_helper *fb_helper)
+{
+}
+
static inline void drm_fb_helper_unregister_info(struct drm_fb_helper
*fb_helper)
{
}
--
2.40.0
Thomas Zimmermann
2023-Mar-20 15:07 UTC
[PATCH v2 4/8] drm/fb-helper: Support smem_len in deferred I/O
The size of the framebuffer can either be stored in screen_info or
smem_len. Take both into account in the deferred I/O code.
Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
---
drivers/gpu/drm/drm_fb_helper.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 7e96ed9efdb5..bb0b25209b3e 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -672,7 +672,7 @@ static void drm_fb_helper_memory_range_to_clip(struct
fb_info *info, off_t off,
void drm_fb_helper_deferred_io(struct fb_info *info, struct list_head
*pagereflist)
{
struct drm_fb_helper *helper = info->par;
- unsigned long start, end, min_off, max_off;
+ unsigned long start, end, min_off, max_off, total_size;
struct fb_deferred_io_pageref *pageref;
struct drm_rect damage_area;
@@ -690,7 +690,11 @@ void drm_fb_helper_deferred_io(struct fb_info *info, struct
list_head *pagerefli
* of the screen and account for non-existing scanlines. Hence,
* keep the covered memory area within the screen buffer.
*/
- max_off = min(max_off, info->screen_size);
+ if (info->screen_size)
+ total_size = info->screen_size;
+ else
+ total_size = info->fix.smem_len;
+ max_off = min(max_off, total_size);
if (min_off < max_off) {
drm_fb_helper_memory_range_to_clip(info, min_off, max_off - min_off,
&damage_area);
--
2.40.0
Thomas Zimmermann
2023-Mar-20 15:07 UTC
[PATCH v2 5/8] drm/fbdev-generic: Set screen size to size of GEM buffer
The size of the screen memory should be equivalent to the size of the screen's GEM buffer. Don't recalculate the value. Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de> --- drivers/gpu/drm/drm_fbdev_generic.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/drm_fbdev_generic.c b/drivers/gpu/drm/drm_fbdev_generic.c index e48a8e82378d..73834a3cc6b0 100644 --- a/drivers/gpu/drm/drm_fbdev_generic.c +++ b/drivers/gpu/drm/drm_fbdev_generic.c @@ -7,6 +7,7 @@ #include <drm/drm_drv.h> #include <drm/drm_fb_helper.h> #include <drm/drm_framebuffer.h> +#include <drm/drm_gem.h> #include <drm/drm_print.h> #include <drm/drm_fbdev_generic.h> @@ -74,8 +75,8 @@ static int drm_fbdev_fb_probe(struct drm_fb_helper *fb_helper, struct drm_client_dev *client = &fb_helper->client; struct drm_device *dev = fb_helper->dev; struct drm_client_buffer *buffer; - struct drm_framebuffer *fb; struct fb_info *info; + size_t screen_size; u32 format; int ret; @@ -91,20 +92,20 @@ static int drm_fbdev_fb_probe(struct drm_fb_helper *fb_helper, fb_helper->buffer = buffer; fb_helper->fb = buffer->fb; - fb = buffer->fb; + screen_size = buffer->gem->size; info = drm_fb_helper_alloc_info(fb_helper); if (IS_ERR(info)) return PTR_ERR(info); info->fbops = &drm_fbdev_fb_ops; - info->screen_size = sizes->surface_height * fb->pitches[0]; - info->fix.smem_len = info->screen_size; + info->screen_size = screen_size; + info->fix.smem_len = screen_size; info->flags = FBINFO_DEFAULT; drm_fb_helper_fill_info(info, fb_helper, sizes); - info->screen_buffer = vzalloc(info->screen_size); + info->screen_buffer = vzalloc(screen_size); if (!info->screen_buffer) return -ENOMEM; info->flags |= FBINFO_VIRTFB | FBINFO_READS_FAST; -- 2.40.0
Thomas Zimmermann
2023-Mar-20 15:07 UTC
[PATCH v2 6/8] drm/fbdev-generic: Clean up after failed probing
Clean up fbdev and client state if the probe function fails. It
used to leak allocated resources. Also reorder the individual steps
to simplify cleanup.
v2:
* move screen_size update into separate patches
Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
Reviewed-by: Javier Martinez Canillas <javierm at redhat.com>
Acked-by: Zack Rusin <zackr at vmware.com>
---
drivers/gpu/drm/drm_fbdev_generic.c | 40 ++++++++++++++++++++---------
1 file changed, 28 insertions(+), 12 deletions(-)
diff --git a/drivers/gpu/drm/drm_fbdev_generic.c
b/drivers/gpu/drm/drm_fbdev_generic.c
index 73834a3cc6b0..e7eeba0c44b4 100644
--- a/drivers/gpu/drm/drm_fbdev_generic.c
+++ b/drivers/gpu/drm/drm_fbdev_generic.c
@@ -77,6 +77,7 @@ static int drm_fbdev_fb_probe(struct drm_fb_helper *fb_helper,
struct drm_client_buffer *buffer;
struct fb_info *info;
size_t screen_size;
+ void *screen_buffer;
u32 format;
int ret;
@@ -92,36 +93,51 @@ static int drm_fbdev_fb_probe(struct drm_fb_helper
*fb_helper,
fb_helper->buffer = buffer;
fb_helper->fb = buffer->fb;
+
screen_size = buffer->gem->size;
+ screen_buffer = vzalloc(screen_size);
+ if (!screen_buffer) {
+ ret = -ENOMEM;
+ goto err_drm_client_framebuffer_delete;
+ }
info = drm_fb_helper_alloc_info(fb_helper);
- if (IS_ERR(info))
- return PTR_ERR(info);
+ if (IS_ERR(info)) {
+ ret = PTR_ERR(info);
+ goto err_vfree;
+ }
+
+ drm_fb_helper_fill_info(info, fb_helper, sizes);
info->fbops = &drm_fbdev_fb_ops;
- info->screen_size = screen_size;
- info->fix.smem_len = screen_size;
info->flags = FBINFO_DEFAULT;
- drm_fb_helper_fill_info(info, fb_helper, sizes);
-
- info->screen_buffer = vzalloc(screen_size);
- if (!info->screen_buffer)
- return -ENOMEM;
+ /* screen */
info->flags |= FBINFO_VIRTFB | FBINFO_READS_FAST;
-
+ info->screen_buffer = screen_buffer;
info->fix.smem_start =
page_to_phys(vmalloc_to_page(info->screen_buffer));
+ info->fix.smem_len = screen_size;
- /* Set a default deferred I/O handler */
+ /* deferred I/O */
fb_helper->fbdefio.delay = HZ / 20;
fb_helper->fbdefio.deferred_io = drm_fb_helper_deferred_io;
info->fbdefio = &fb_helper->fbdefio;
ret = fb_deferred_io_init(info);
if (ret)
- return ret;
+ goto err_drm_fb_helper_release_info;
return 0;
+
+err_drm_fb_helper_release_info:
+ drm_fb_helper_release_info(fb_helper);
+err_vfree:
+ vfree(screen_buffer);
+err_drm_client_framebuffer_delete:
+ fb_helper->fb = NULL;
+ fb_helper->buffer = NULL;
+ drm_client_framebuffer_delete(buffer);
+ return ret;
}
static void drm_fbdev_damage_blit_real(struct drm_fb_helper *fb_helper,
--
2.40.0
Thomas Zimmermann
2023-Mar-20 15:07 UTC
[PATCH v2 7/8] drm/fb-helper: Consolidate CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM
Consolidate all handling of CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM by
making the module parameter optional in drm_fb_helper.c.
Without the config option, modules can set smem_start in struct
fb_info for internal usage, but not export if to userspace. The
address can only be exported by enabling the option and setting
the module parameter. Also update the comment.
Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
Reviewed-by: Javier Martinez Canillas <javierm at redhat.com>
Acked-by: Zack Rusin <zackr at vmware.com>
---
drivers/gpu/drm/drm_fb_helper.c | 22 ++++++++--------------
drivers/gpu/drm/drm_fbdev_dma.c | 9 +--------
include/drm/drm_fb_helper.h | 9 ---------
3 files changed, 9 insertions(+), 31 deletions(-)
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index bb0b25209b3e..63ec95e86d0e 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -60,16 +60,17 @@ MODULE_PARM_DESC(drm_fbdev_overalloc,
* In order to keep user-space compatibility, we want in certain use-cases
* to keep leaking the fbdev physical address to the user-space program
* handling the fbdev buffer.
- * This is a bad habit essentially kept into closed source opengl driver
- * that should really be moved into open-source upstream projects instead
- * of using legacy physical addresses in user space to communicate with
- * other out-of-tree kernel modules.
+ *
+ * This is a bad habit, essentially kept to support closed-source OpenGL
+ * drivers that should really be moved into open-source upstream projects
+ * instead of using legacy physical addresses in user space to communicate
+ * with other out-of-tree kernel modules.
*
* This module_param *should* be removed as soon as possible and be
* considered as a broken and legacy behaviour from a modern fbdev device.
*/
-#if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM)
static bool drm_leak_fbdev_smem;
+#if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM)
module_param_unsafe(drm_leak_fbdev_smem, bool, 0600);
MODULE_PARM_DESC(drm_leak_fbdev_smem,
"Allow unsafe leaking fbdev physical smem address
[default=false]");
@@ -1983,10 +1984,6 @@ static int drm_fb_helper_single_fb_probe(struct
drm_fb_helper *fb_helper)
return ret;
}
-#if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM)
- fb_helper->hint_leak_smem_start = drm_leak_fbdev_smem;
-#endif
-
/* push down into drivers */
ret = (*fb_helper->funcs->fb_probe)(fb_helper, &sizes);
if (ret < 0)
@@ -2185,11 +2182,8 @@ __drm_fb_helper_initial_config_and_unlock(struct
drm_fb_helper *fb_helper)
info = fb_helper->info;
info->var.pixclock = 0;
- /* Shamelessly allow physical address leaking to userspace */
-#if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM)
- if (!fb_helper->hint_leak_smem_start)
-#endif
- /* don't leak any physical addresses to userspace */
+
+ if (!drm_leak_fbdev_smem)
info->flags |= FBINFO_HIDE_SMEM_START;
/* Need to drop locks to avoid recursive deadlock in
diff --git a/drivers/gpu/drm/drm_fbdev_dma.c b/drivers/gpu/drm/drm_fbdev_dma.c
index cf553ac12a0f..728deffcc0d9 100644
--- a/drivers/gpu/drm/drm_fbdev_dma.c
+++ b/drivers/gpu/drm/drm_fbdev_dma.c
@@ -136,16 +136,9 @@ static int drm_fbdev_dma_helper_fb_probe(struct
drm_fb_helper *fb_helper,
info->flags |= FBINFO_READS_FAST; /* signal caching */
info->screen_size = sizes->surface_height * fb->pitches[0];
info->screen_buffer = map.vaddr;
+ info->fix.smem_start = page_to_phys(virt_to_page(info->screen_buffer));
info->fix.smem_len = info->screen_size;
-#if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM)
- /*
- * Shamelessly leak the physical address to user-space.
- */
- if (fb_helper->hint_leak_smem_start && !info->fix.smem_start)
- info->fix.smem_start = page_to_phys(virt_to_page(info->screen_buffer));
-#endif
-
return 0;
err_drm_client_buffer_vunmap:
diff --git a/include/drm/drm_fb_helper.h b/include/drm/drm_fb_helper.h
index c5822ec2fdd1..72032c354a30 100644
--- a/include/drm/drm_fb_helper.h
+++ b/include/drm/drm_fb_helper.h
@@ -195,15 +195,6 @@ struct drm_fb_helper {
*/
int preferred_bpp;
- /**
- * @hint_leak_smem_start:
- *
- * Hint to the fbdev emulation to store the framebuffer's physical
- * address in struct &fb_info.fix.smem_start. If the hint is unset,
- * the smem_start field should always be cleared to zero.
- */
- bool hint_leak_smem_start;
-
#ifdef CONFIG_FB_DEFERRED_IO
/**
* @fbdefio:
--
2.40.0
Rename symbols to match the style of other fbdev-emulation source
code. No functional changes.
Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
Reviewed-by: Javier Martinez Canillas <javierm at redhat.com>
Acked-by: Zack Rusin <zackr at vmware.com>
---
drivers/gpu/drm/drm_fbdev_generic.c | 66 ++++++++++++++---------------
1 file changed, 33 insertions(+), 33 deletions(-)
diff --git a/drivers/gpu/drm/drm_fbdev_generic.c
b/drivers/gpu/drm/drm_fbdev_generic.c
index e7eeba0c44b4..8e5148bf40bb 100644
--- a/drivers/gpu/drm/drm_fbdev_generic.c
+++ b/drivers/gpu/drm/drm_fbdev_generic.c
@@ -13,7 +13,7 @@
#include <drm/drm_fbdev_generic.h>
/* @user: 1=userspace, 0=fbcon */
-static int drm_fbdev_fb_open(struct fb_info *info, int user)
+static int drm_fbdev_generic_fb_open(struct fb_info *info, int user)
{
struct drm_fb_helper *fb_helper = info->par;
@@ -24,7 +24,7 @@ static int drm_fbdev_fb_open(struct fb_info *info, int user)
return 0;
}
-static int drm_fbdev_fb_release(struct fb_info *info, int user)
+static int drm_fbdev_generic_fb_release(struct fb_info *info, int user)
{
struct drm_fb_helper *fb_helper = info->par;
@@ -34,7 +34,7 @@ static int drm_fbdev_fb_release(struct fb_info *info, int
user)
return 0;
}
-static void drm_fbdev_fb_destroy(struct fb_info *info)
+static void drm_fbdev_generic_fb_destroy(struct fb_info *info)
{
struct drm_fb_helper *fb_helper = info->par;
void *shadow = info->screen_buffer;
@@ -52,10 +52,10 @@ static void drm_fbdev_fb_destroy(struct fb_info *info)
kfree(fb_helper);
}
-static const struct fb_ops drm_fbdev_fb_ops = {
+static const struct fb_ops drm_fbdev_generic_fb_ops = {
.owner = THIS_MODULE,
- .fb_open = drm_fbdev_fb_open,
- .fb_release = drm_fbdev_fb_release,
+ .fb_open = drm_fbdev_generic_fb_open,
+ .fb_release = drm_fbdev_generic_fb_release,
.fb_read = drm_fb_helper_sys_read,
.fb_write = drm_fb_helper_sys_write,
DRM_FB_HELPER_DEFAULT_OPS,
@@ -63,14 +63,14 @@ static const struct fb_ops drm_fbdev_fb_ops = {
.fb_copyarea = drm_fb_helper_sys_copyarea,
.fb_imageblit = drm_fb_helper_sys_imageblit,
.fb_mmap = fb_deferred_io_mmap,
- .fb_destroy = drm_fbdev_fb_destroy,
+ .fb_destroy = drm_fbdev_generic_fb_destroy,
};
/*
* This function uses the client API to create a framebuffer backed by a dumb
buffer.
*/
-static int drm_fbdev_fb_probe(struct drm_fb_helper *fb_helper,
- struct drm_fb_helper_surface_size *sizes)
+static int drm_fbdev_generic_helper_fb_probe(struct drm_fb_helper *fb_helper,
+ struct drm_fb_helper_surface_size *sizes)
{
struct drm_client_dev *client = &fb_helper->client;
struct drm_device *dev = fb_helper->dev;
@@ -109,7 +109,7 @@ static int drm_fbdev_fb_probe(struct drm_fb_helper
*fb_helper,
drm_fb_helper_fill_info(info, fb_helper, sizes);
- info->fbops = &drm_fbdev_fb_ops;
+ info->fbops = &drm_fbdev_generic_fb_ops;
info->flags = FBINFO_DEFAULT;
/* screen */
@@ -140,9 +140,9 @@ static int drm_fbdev_fb_probe(struct drm_fb_helper
*fb_helper,
return ret;
}
-static void drm_fbdev_damage_blit_real(struct drm_fb_helper *fb_helper,
- struct drm_clip_rect *clip,
- struct iosys_map *dst)
+static void drm_fbdev_generic_damage_blit_real(struct drm_fb_helper *fb_helper,
+ struct drm_clip_rect *clip,
+ struct iosys_map *dst)
{
struct drm_framebuffer *fb = fb_helper->fb;
size_t offset = clip->y1 * fb->pitches[0];
@@ -179,8 +179,8 @@ static void drm_fbdev_damage_blit_real(struct drm_fb_helper
*fb_helper,
}
}
-static int drm_fbdev_damage_blit(struct drm_fb_helper *fb_helper,
- struct drm_clip_rect *clip)
+static int drm_fbdev_generic_damage_blit(struct drm_fb_helper *fb_helper,
+ struct drm_clip_rect *clip)
{
struct drm_client_buffer *buffer = fb_helper->buffer;
struct iosys_map map, dst;
@@ -204,7 +204,7 @@ static int drm_fbdev_damage_blit(struct drm_fb_helper
*fb_helper,
goto out;
dst = map;
- drm_fbdev_damage_blit_real(fb_helper, clip, &dst);
+ drm_fbdev_generic_damage_blit_real(fb_helper, clip, &dst);
drm_client_buffer_vunmap(buffer);
@@ -214,7 +214,8 @@ static int drm_fbdev_damage_blit(struct drm_fb_helper
*fb_helper,
return ret;
}
-static int drm_fbdev_fb_dirty(struct drm_fb_helper *helper, struct
drm_clip_rect *clip)
+static int drm_fbdev_generic_helper_fb_dirty(struct drm_fb_helper *helper,
+ struct drm_clip_rect *clip)
{
struct drm_device *dev = helper->dev;
int ret;
@@ -223,7 +224,7 @@ static int drm_fbdev_fb_dirty(struct drm_fb_helper *helper,
struct drm_clip_rect
if (!(clip->x1 < clip->x2 && clip->y1 < clip->y2))
return 0;
- ret = drm_fbdev_damage_blit(helper, clip);
+ ret = drm_fbdev_generic_damage_blit(helper, clip);
if (drm_WARN_ONCE(dev, ret, "Damage blitter failed: ret=%d\n", ret))
return ret;
@@ -236,12 +237,12 @@ static int drm_fbdev_fb_dirty(struct drm_fb_helper
*helper, struct drm_clip_rect
return 0;
}
-static const struct drm_fb_helper_funcs drm_fb_helper_generic_funcs = {
- .fb_probe = drm_fbdev_fb_probe,
- .fb_dirty = drm_fbdev_fb_dirty,
+static const struct drm_fb_helper_funcs drm_fbdev_generic_helper_funcs = {
+ .fb_probe = drm_fbdev_generic_helper_fb_probe,
+ .fb_dirty = drm_fbdev_generic_helper_fb_dirty,
};
-static void drm_fbdev_client_unregister(struct drm_client_dev *client)
+static void drm_fbdev_generic_client_unregister(struct drm_client_dev *client)
{
struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
@@ -254,14 +255,14 @@ static void drm_fbdev_client_unregister(struct
drm_client_dev *client)
}
}
-static int drm_fbdev_client_restore(struct drm_client_dev *client)
+static int drm_fbdev_generic_client_restore(struct drm_client_dev *client)
{
drm_fb_helper_lastclose(client->dev);
return 0;
}
-static int drm_fbdev_client_hotplug(struct drm_client_dev *client)
+static int drm_fbdev_generic_client_hotplug(struct drm_client_dev *client)
{
struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
struct drm_device *dev = client->dev;
@@ -290,11 +291,11 @@ static int drm_fbdev_client_hotplug(struct drm_client_dev
*client)
return ret;
}
-static const struct drm_client_funcs drm_fbdev_client_funcs = {
+static const struct drm_client_funcs drm_fbdev_generic_client_funcs = {
.owner = THIS_MODULE,
- .unregister = drm_fbdev_client_unregister,
- .restore = drm_fbdev_client_restore,
- .hotplug = drm_fbdev_client_hotplug,
+ .unregister = drm_fbdev_generic_client_unregister,
+ .restore = drm_fbdev_generic_client_restore,
+ .hotplug = drm_fbdev_generic_client_hotplug,
};
/**
@@ -320,8 +321,7 @@ static const struct drm_client_funcs drm_fbdev_client_funcs
= {
*
* The fbdev is destroyed by drm_dev_unregister().
*/
-void drm_fbdev_generic_setup(struct drm_device *dev,
- unsigned int preferred_bpp)
+void drm_fbdev_generic_setup(struct drm_device *dev, unsigned int
preferred_bpp)
{
struct drm_fb_helper *fb_helper;
int ret;
@@ -332,15 +332,15 @@ void drm_fbdev_generic_setup(struct drm_device *dev,
fb_helper = kzalloc(sizeof(*fb_helper), GFP_KERNEL);
if (!fb_helper)
return;
- drm_fb_helper_prepare(dev, fb_helper, preferred_bpp,
&drm_fb_helper_generic_funcs);
+ drm_fb_helper_prepare(dev, fb_helper, preferred_bpp,
&drm_fbdev_generic_helper_funcs);
- ret = drm_client_init(dev, &fb_helper->client, "fbdev",
&drm_fbdev_client_funcs);
+ ret = drm_client_init(dev, &fb_helper->client, "fbdev",
&drm_fbdev_generic_client_funcs);
if (ret) {
drm_err(dev, "Failed to register client: %d\n", ret);
goto err_drm_client_init;
}
- ret = drm_fbdev_client_hotplug(&fb_helper->client);
+ ret = drm_fbdev_generic_client_hotplug(&fb_helper->client);
if (ret)
drm_dbg_kms(dev, "client hotplug ret=%d\n", ret);
--
2.40.0