From 4748aa16d5273bf4b42d3581e5e33da1faa69722 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 7 Nov 2019 18:05:58 +0000 Subject: drm: Expose a method for creating anonymous struct file around drm_minor Sometimes we need to create a struct file to wrap a drm_device, as it the user were to have opened /dev/dri/card0 but to do so anonymously (i.e. for internal use). Provide a utility method to create a struct file with the drm_device->driver.fops, that wrap the drm_device. v2: Restrict usage to selftests Signed-off-by: Chris Wilson Cc: Daniel Vetter Reviewed-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20191107180601.30815-2-chris@chris-wilson.co.uk --- drivers/gpu/drm/drm_file.c | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) (limited to 'drivers/gpu/drm/drm_file.c') diff --git a/drivers/gpu/drm/drm_file.c b/drivers/gpu/drm/drm_file.c index ea34bc991858..4d9385d1bf2d 100644 --- a/drivers/gpu/drm/drm_file.c +++ b/drivers/gpu/drm/drm_file.c @@ -31,7 +31,9 @@ * OTHER DEALINGS IN THE SOFTWARE. */ +#include #include +#include #include #include #include @@ -754,3 +756,43 @@ void drm_send_event(struct drm_device *dev, struct drm_pending_event *e) spin_unlock_irqrestore(&dev->event_lock, irqflags); } EXPORT_SYMBOL(drm_send_event); + +/** + * mock_drm_getfile - Create a new struct file for the drm device + * @minor: drm minor to wrap (e.g. #drm_device.primary) + * @flags: file creation mode (O_RDWR etc) + * + * This create a new struct file that wraps a DRM file context around a + * DRM minor. This mimicks userspace opening e.g. /dev/dri/card0, but without + * invoking userspace. The struct file may be operated on using its f_op + * (the drm_device.driver.fops) to mimick userspace operations, or be supplied + * to userspace facing functions as an internal/anonymous client. + * + * RETURNS: + * Pointer to newly created struct file, ERR_PTR on failure. + */ +struct file *mock_drm_getfile(struct drm_minor *minor, unsigned int flags) +{ + struct drm_device *dev = minor->dev; + struct drm_file *priv; + struct file *file; + + priv = drm_file_alloc(minor); + if (IS_ERR(priv)) + return ERR_CAST(priv); + + file = anon_inode_getfile("drm", dev->driver->fops, priv, flags); + if (IS_ERR(file)) { + drm_file_free(priv); + return file; + } + + /* Everyone shares a single global address space */ + file->f_mapping = dev->anon_inode->i_mapping; + + drm_dev_get(dev); + priv->filp = file; + + return file; +} +EXPORT_SYMBOL_FOR_TESTS_ONLY(mock_drm_getfile); -- cgit v1.2.3