Re: [RFC v4 16/25] drm: Make ioctls available for in-kernel clients

On Sat, Apr 14, 2018 at 01:53:09PM +0200, Noralf Trønnes wrote:

Make ioctl wrappers for functions that will be used by the in-kernel API. The following functions are touched:

• drm_mode_create_dumb_ioctl()
• drm_mode_destroy_dumb_ioctl()
• drm_mode_addfb2()
• drm_mode_rmfb()
• drm_prime_handle_to_fd_ioctl()

drm_mode_addfb2() also gets the ability to override the debug name.

Signed-off-by: Noralf Trønnes noralf@tronnes.org

drivers/gpu/drm/drm_crtc_internal.h | 18 ++++++++++--- drivers/gpu/drm/drm_dumb_buffers.c | 33 ++++++++++++++++-------- drivers/gpu/drm/drm_framebuffer.c | 50 ++++++++++++++++++++++++------------- drivers/gpu/drm/drm_internal.h | 3 +++ drivers/gpu/drm/drm_ioc32.c | 2 +- drivers/gpu/drm/drm_ioctl.c | 4 +-- drivers/gpu/drm/drm_prime.c | 13 +++++++--- 7 files changed, 84 insertions(+), 39 deletions(-)

diff --git a/drivers/gpu/drm/drm_crtc_internal.h b/drivers/gpu/drm/drm_crtc_internal.h index 3c2b82865ad2..8f8886ac0e4d 100644 --- a/drivers/gpu/drm/drm_crtc_internal.h +++ b/drivers/gpu/drm/drm_crtc_internal.h @@ -62,6 +62,12 @@ int drm_mode_getresources(struct drm_device *dev,

/* drm_dumb_buffers.c */ +int drm_mode_create_dumb(struct drm_device *dev,

• 	 struct drm_mode_create_dumb *args,
  

• 	 struct drm_file *file_priv);
  

+int drm_mode_destroy_dumb(struct drm_device *dev, u32 handle,

• 	  struct drm_file *file_priv);
  

/* IOCTLs */ int drm_mode_create_dumb_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv); @@ -163,14 +169,18 @@ int drm_framebuffer_check_src_coords(uint32_t src_x, uint32_t src_y, const struct drm_framebuffer *fb); void drm_fb_release(struct drm_file *file_priv);

+int drm_mode_addfb2(struct drm_device *dev, struct drm_mode_fb_cmd2 *r,

•     struct drm_file *file_priv, const char *comm);
  

+int drm_mode_rmfb(struct drm_device *dev, u32 fb_id,

•   struct drm_file *file_priv);
  
  

/* IOCTL */ int drm_mode_addfb(struct drm_device *dev, void *data, struct drm_file *file_priv); -int drm_mode_addfb2(struct drm_device *dev,

•     void *data, struct drm_file *file_priv);
  

-int drm_mode_rmfb(struct drm_device *dev,

•   void *data, struct drm_file *file_priv);
  

+int drm_mode_addfb2_ioctl(struct drm_device *dev,

• 	  void *data, struct drm_file *file_priv);
  

+int drm_mode_rmfb_ioctl(struct drm_device *dev,

• 	void *data, struct drm_file *file_priv);
  

int drm_mode_getfb(struct drm_device *dev, void *data, struct drm_file *file_priv); int drm_mode_dirtyfb_ioctl(struct drm_device *dev, diff --git a/drivers/gpu/drm/drm_dumb_buffers.c b/drivers/gpu/drm/drm_dumb_buffers.c index 39ac15ce4702..eed9687b8698 100644 --- a/drivers/gpu/drm/drm_dumb_buffers.c +++ b/drivers/gpu/drm/drm_dumb_buffers.c @@ -53,10 +53,10 @@

• a hardware-specific ioctl to allocate suitable buffer objects.

*/

-int drm_mode_create_dumb_ioctl(struct drm_device *dev,

• 	       void *data, struct drm_file *file_priv)
  

+int drm_mode_create_dumb(struct drm_device *dev,

• 	 struct drm_mode_create_dumb *args,
  

• 	 struct drm_file *file_priv)
  

{

• struct drm_mode_create_dumb *args = data; u32 cpp, stride, size;

  if (!dev->driver->dumb_create)

@@ -91,6 +91,12 @@ int drm_mode_create_dumb_ioctl(struct drm_device *dev, return dev->driver->dumb_create(file_priv, dev, args); }

+int drm_mode_create_dumb_ioctl(struct drm_device *dev,

• 	       void *data, struct drm_file *file_priv)
  

+{

• return drm_mode_create_dumb(dev, data, file_priv);

+}

/**

• drm_mode_mmap_dumb_ioctl - create an mmap offset for a dumb backing storage buffer
• @dev: DRM device

@@ -122,17 +128,22 @@ int drm_mode_mmap_dumb_ioctl(struct drm_device *dev, &args->offset); }

+int drm_mode_destroy_dumb(struct drm_device *dev, u32 handle,

• 	  struct drm_file *file_priv)
  

+{

• if (!dev->driver->dumb_create)

• return -ENOSYS;
  

• if (dev->driver->dumb_destroy)

• return dev->driver->dumb_destroy(file_priv, dev, handle);
  

• else

• return drm_gem_dumb_destroy(file_priv, dev, handle);
  

+}

int drm_mode_destroy_dumb_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) { struct drm_mode_destroy_dumb *args = data;

• if (!dev->driver->dumb_create)

• return -ENOSYS;
  

• if (dev->driver->dumb_destroy)

• return dev->driver->dumb_destroy(file_priv, dev, args->handle);
  

• else

• return drm_gem_dumb_destroy(file_priv, dev, args->handle);
  

• return drm_mode_destroy_dumb(dev, args->handle, file_priv);

}

diff --git a/drivers/gpu/drm/drm_framebuffer.c b/drivers/gpu/drm/drm_framebuffer.c index 8c4d32adcc17..16769e4db5c0 100644 --- a/drivers/gpu/drm/drm_framebuffer.c +++ b/drivers/gpu/drm/drm_framebuffer.c @@ -125,7 +125,7 @@ int drm_mode_addfb(struct drm_device *dev, dev->driver->driver_features & DRIVER_PREFER_XBGR_30BPP) r.pixel_format = DRM_FORMAT_XBGR2101010;

• ret = drm_mode_addfb2(dev, &r, file_priv);

• ret = drm_mode_addfb2_ioctl(dev, &r, file_priv); if (ret) return ret;

@@ -310,23 +310,23 @@ drm_internal_framebuffer_create(struct drm_device *dev,

/**

• drm_mode_addfb2 - add an FB to the graphics configuration

• • @dev: drm device for the ioctl
• • @data: data pointer for the ioctl
• • @file_priv: drm file for the ioctl call

• • @dev: drm device
• • @r: pointer to request structure
• • @file_priv: drm file
• • @comm: optionally override the allocator name used for debug output
  • Add a new FB to the specified CRTC, given a user request with format. This is
  • the 2nd version of the addfb ioctl, which supports multi-planar framebuffers
  • and uses fourcc codes as pixel format specifiers.

• • Called by the user via ioctl.

• • Called by the user via ioctl, or by an in-kernel client.
  • Returns:
  • Zero on success, negative errno on failure.
  */

-int drm_mode_addfb2(struct drm_device *dev,

•     void *data, struct drm_file *file_priv)
  

+int drm_mode_addfb2(struct drm_device *dev, struct drm_mode_fb_cmd2 *r,

•     struct drm_file *file_priv, const char *comm)
  

API bikeshed: I'd drop the 2 (it's not relevant for in-kernel users), and maybe return the handle right away to avoid callers having to do silly stuff? If the return value is 0, then something failed.

Could even make @r const, if we do a quick on-stack copy to reinforce that idea.

But feel free to ignore, probably not making things better here :-)

{

• struct drm_mode_fb_cmd2 *r = data; struct drm_framebuffer *fb;

  if (!drm_core_check_feature(dev, DRIVER_MODESET))

@@ -336,6 +336,9 @@ int drm_mode_addfb2(struct drm_device *dev, if (IS_ERR(fb)) return PTR_ERR(fb);

• if (comm)

• strscpy(fb->comm, comm, TASK_COMM_LEN);
  

• DRM_DEBUG_KMS("[FB:%d]\n", fb->base.id); r->fb_id = fb->base.id;

@@ -347,6 +350,12 @@ int drm_mode_addfb2(struct drm_device *dev, return 0; }

+int drm_mode_addfb2_ioctl(struct drm_device *dev,

• 	  void *data, struct drm_file *file_priv)
  

+{

• return drm_mode_addfb2(dev, data, file_priv, NULL);

+}

struct drm_mode_rmfb_work { struct work_struct work; struct list_head fbs; @@ -367,29 +376,28 @@ static void drm_mode_rmfb_work_fn(struct work_struct *w)

/**

• drm_mode_rmfb - remove an FB from the configuration

• • @dev: drm device for the ioctl
• • @data: data pointer for the ioctl
• • @file_priv: drm file for the ioctl call

• • @dev: drm device
• • @fb_id: id of framebuffer to remove
• • @file_priv: drm file

• • Remove the FB specified by the user.

• • Remove the specified FB.

• • Called by the user via ioctl.

• • Called by the user via ioctl, or by an in-kernel client.
  • Returns:
  • Zero on success, negative errno on failure.
  */

-int drm_mode_rmfb(struct drm_device *dev,

•    void *data, struct drm_file *file_priv)
  

+int drm_mode_rmfb(struct drm_device *dev, u32 fb_id,

•   struct drm_file *file_priv)
  

{ struct drm_framebuffer *fb = NULL; struct drm_framebuffer *fbl = NULL;

• uint32_t *id = data; int found = 0;

  if (!drm_core_check_feature(dev, DRIVER_MODESET)) return -EINVAL;

• fb = drm_framebuffer_lookup(dev, file_priv, *id);

• fb = drm_framebuffer_lookup(dev, file_priv, fb_id); if (!fb) return -ENOENT;

@@ -435,6 +443,14 @@ int drm_mode_rmfb(struct drm_device *dev, return -ENOENT; }

+int drm_mode_rmfb_ioctl(struct drm_device *dev,

• 	void *data, struct drm_file *file_priv)
  

+{

• uint32_t *fb_id = data;
• return drm_mode_rmfb(dev, *fb_id, file_priv);

+}

/**

• drm_mode_getfb - get FB info
• @dev: drm device for the ioctl

diff --git a/drivers/gpu/drm/drm_internal.h b/drivers/gpu/drm/drm_internal.h index 40179c5fc6b8..3f5d7706bcc9 100644 --- a/drivers/gpu/drm/drm_internal.h +++ b/drivers/gpu/drm/drm_internal.h @@ -37,6 +37,9 @@ void drm_pci_agp_destroy(struct drm_device *dev); int drm_pci_set_busid(struct drm_device *dev, struct drm_master *master);

/* drm_prime.c */ +int drm_prime_handle_to_fd(struct drm_device *dev,

• 	   struct drm_prime_handle *args,
  

• 	   struct drm_file *file_priv);
  

int drm_prime_handle_to_fd_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv); int drm_prime_fd_to_handle_ioctl(struct drm_device *dev, void *data, diff --git a/drivers/gpu/drm/drm_ioc32.c b/drivers/gpu/drm/drm_ioc32.c index f8e96e648acf..576d00b7dad5 100644 --- a/drivers/gpu/drm/drm_ioc32.c +++ b/drivers/gpu/drm/drm_ioc32.c @@ -884,7 +884,7 @@ static int compat_drm_mode_addfb2(struct file *file, unsigned int cmd, sizeof(req64.modifier))) return -EFAULT;

• err = drm_ioctl_kernel(file, drm_mode_addfb2, &req64,

• err = drm_ioctl_kernel(file, drm_mode_addfb2_ioctl, &req64, DRM_CONTROL_ALLOW|DRM_UNLOCKED); if (err) return err;

diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c index af782911c505..c69fda5d3875 100644 --- a/drivers/gpu/drm/drm_ioctl.c +++ b/drivers/gpu/drm/drm_ioctl.c @@ -635,8 +635,8 @@ static const struct drm_ioctl_desc drm_ioctls[] = { DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED), DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),

• DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
• DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),

• DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
• DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED), DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED), DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),

diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c index caf675e3e692..e6052ab2bec4 100644 --- a/drivers/gpu/drm/drm_prime.c +++ b/drivers/gpu/drm/drm_prime.c @@ -866,11 +866,10 @@ int drm_gem_prime_fd_to_handle(struct drm_device *dev,

Like with the dumb ioctls you probably want to unwrap this some more here for the prime stuff. I don't think you want the actual fd, but just the underlying struct dma_buf.

Unfortunately this means a bit of rework, since atm the drm_driver->handle_to_fd also gives us the fd, not the dma_buf. Here's what we need (assuming we really need struct dma_buf, and not just a gem bo, which is much easier to get at):

- Change the drm_driver->handle_to_fd interface to handle_to_dma_buf, and put the final dma_buf_fd into drm_prime_handle_to_fd_ioctl. Since dma_buf_fd should already be the very last step (otherwise an implementation is most likely buggy) this shouldn't be a huge step.

If dma_buf_fd fails, then we just do a dma_but_put (aka the ->handle_to_dma_buf callback needs to give us a reference we can use).

- For the internal function just call ->handle_to_dmabuf directly, but don't convert to an fd.

- Similar for the other direction. But I think we don't really need that: We start with the handle from the dumb api, going back to the handle shouldn't ever be needed. Probably best to just remove that.

We can't just create file-descriptors in random calling context (userspace might get upset, no idea what happens from kernel threads).

The dumb buffer internal interfaces lgtm. -Daniel

} EXPORT_SYMBOL(drm_gem_prime_fd_to_handle);

-int drm_prime_handle_to_fd_ioctl(struct drm_device *dev, void *data,

• 		 struct drm_file *file_priv)
  

+int drm_prime_handle_to_fd(struct drm_device *dev,

• 	   struct drm_prime_handle *args,
  

• 	   struct drm_file *file_priv)
  

{

• struct drm_prime_handle *args = data;
• if (!drm_core_check_feature(dev, DRIVER_PRIME)) return -EINVAL;

@@ -885,6 +884,12 @@ int drm_prime_handle_to_fd_ioctl(struct drm_device *dev, void *data, args->handle, args->flags, &args->fd); }

+int drm_prime_handle_to_fd_ioctl(struct drm_device *dev, void *data,

• 		 struct drm_file *file_priv)
  

+{

• return drm_prime_handle_to_fd(dev, data, file_priv);

+}

int drm_prime_fd_to_handle_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) { -- 2.15.1

---

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