Message ID | 1440631758-30303-2-git-send-email-tiago.vignatti@intel.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Hi all, On 27 August 2015 at 00:29, Tiago Vignatti <tiago.vignatti@intel.com> wrote: > From: Daniel Thompson <daniel.thompson@linaro.org> > > Currently DRM_IOCTL_PRIME_HANDLE_TO_FD rejects all flags except > (DRM|O)_CLOEXEC making it difficult (maybe impossible) for userspace > to mmap() the resulting dma-buf even when this is supported by the > DRM driver. > > It is trivial to relax the restriction and permit read/write access. > This is safe because the flags are seldom touched by drm; mostly they > are passed verbatim to dma_buf calls. > Strictly speaking shouldn't this patch be the last one in the series ? I.e. we should lift this restriction, after the sync method (ioctl/syscall/etc.) is in place. Or perhaps I missed something ? Thanks Emil
On 08/27/2015 01:36 PM, Emil Velikov wrote: > Hi all, > > On 27 August 2015 at 00:29, Tiago Vignatti <tiago.vignatti@intel.com> wrote: >> From: Daniel Thompson <daniel.thompson@linaro.org> >> >> Currently DRM_IOCTL_PRIME_HANDLE_TO_FD rejects all flags except >> (DRM|O)_CLOEXEC making it difficult (maybe impossible) for userspace >> to mmap() the resulting dma-buf even when this is supported by the >> DRM driver. >> >> It is trivial to relax the restriction and permit read/write access. >> This is safe because the flags are seldom touched by drm; mostly they >> are passed verbatim to dma_buf calls. >> > Strictly speaking shouldn't this patch be the last one in the series ? > I.e. we should lift this restriction, after the sync method > (ioctl/syscall/etc.) is in place. Or perhaps I missed something ? I think you're right about it, Emil. Thank you, Tiago
diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c index 27aa718..df6cdc7 100644 --- a/drivers/gpu/drm/drm_prime.c +++ b/drivers/gpu/drm/drm_prime.c @@ -329,7 +329,7 @@ static const struct dma_buf_ops drm_gem_prime_dmabuf_ops = { * drm_gem_prime_export - helper library implementation of the export callback * @dev: drm_device to export from * @obj: GEM object to export - * @flags: flags like DRM_CLOEXEC + * @flags: flags like DRM_CLOEXEC and DRM_RDWR * * This is the implementation of the gem_prime_export functions for GEM drivers * using the PRIME helpers. @@ -628,7 +628,6 @@ int drm_prime_handle_to_fd_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) { struct drm_prime_handle *args = data; - uint32_t flags; if (!drm_core_check_feature(dev, DRIVER_PRIME)) return -EINVAL; @@ -637,14 +636,11 @@ int drm_prime_handle_to_fd_ioctl(struct drm_device *dev, void *data, return -ENOSYS; /* check flags are valid */ - if (args->flags & ~DRM_CLOEXEC) + if (args->flags & ~(DRM_CLOEXEC | DRM_RDWR)) return -EINVAL; - /* we only want to pass DRM_CLOEXEC which is == O_CLOEXEC */ - flags = args->flags & DRM_CLOEXEC; - return dev->driver->prime_handle_to_fd(dev, file_priv, - args->handle, flags, &args->fd); + args->handle, args->flags, &args->fd); } int drm_prime_fd_to_handle_ioctl(struct drm_device *dev, void *data, diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h index 3801584..ad8223e 100644 --- a/include/uapi/drm/drm.h +++ b/include/uapi/drm/drm.h @@ -668,6 +668,7 @@ struct drm_set_client_cap { __u64 value; }; +#define DRM_RDWR O_RDWR #define DRM_CLOEXEC O_CLOEXEC struct drm_prime_handle { __u32 handle;