| Message ID | 1450341626-6695-23-git-send-email-laurent.pinchart+renesas@ideasonboard.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Laurent, Thanks for the set! On Thu, Dec 17, 2015 at 10:40:00AM +0200, Laurent Pinchart wrote: > The media devnode core associates devnodes with files by storing the > devnode pointer in the file structure private_data field. In order to > allow tracking of per-file-handle data introduce a new media devnode > file handle structure that stores the devnode pointer, and store a > pointer to that structure in the file private_data field. > > Users of the media devnode code (the only existing user being > media_device) are responsible for managing their own subclass of the > media_devnode_fh structure. > > Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> > --- > drivers/media/media-device.c | 22 ++++++++++++++++++++++ > drivers/media/media-devnode.c | 19 +++++++++---------- > include/media/media-devnode.h | 18 +++++++++++++++++- > 3 files changed, 48 insertions(+), 11 deletions(-) > > diff --git a/drivers/media/media-device.c b/drivers/media/media-device.c > index 7b39440192d6..285f7d79d848 100644 > --- a/drivers/media/media-device.c > +++ b/drivers/media/media-device.c > @@ -24,23 +24,45 @@ > #include <linux/export.h> > #include <linux/ioctl.h> > #include <linux/media.h> > +#include <linux/slab.h> > #include <linux/types.h> > > #include <media/media-device.h> > #include <media/media-devnode.h> > #include <media/media-entity.h> > > +struct media_device_fh { > + struct media_devnode_fh fh; > +}; > + > +static inline struct media_device_fh *media_device_fh(struct file *filp) > +{ > + return container_of(filp->private_data, struct media_device_fh, fh); > +} > + > /* ----------------------------------------------------------------------------- > * Userspace API > */ > > static int media_device_open(struct file *filp) > { > + struct media_device_fh *fh; > + > + fh = kzalloc(sizeof(*media_device_fh), GFP_KERNEL); sizeof(*fh) ? With that fixed, Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com> > + if (!fh) > + return -ENOMEM; > + > + filp->private_data = &fh->fh; > + > return 0; > } > > static int media_device_close(struct file *filp) > { > + struct media_device_fh *fh = media_device_fh(filp); > + > + kfree(fh); > + > return 0; > } > > diff --git a/drivers/media/media-devnode.c b/drivers/media/media-devnode.c > index ebf9626e5ae5..67bac29838d3 100644 > --- a/drivers/media/media-devnode.c > +++ b/drivers/media/media-devnode.c > @@ -154,6 +154,7 @@ static long media_compat_ioctl(struct file *filp, unsigned int cmd, > /* Override for the open function */ > static int media_open(struct inode *inode, struct file *filp) > { > + struct media_devnode_fh *fh; > struct media_devnode *mdev; > int ret; > > @@ -175,16 +176,15 @@ static int media_open(struct inode *inode, struct file *filp) > get_device(&mdev->dev); > mutex_unlock(&media_devnode_lock); > > - filp->private_data = mdev; > - > - if (mdev->fops->open) { > - ret = mdev->fops->open(filp); > - if (ret) { > - put_device(&mdev->dev); > - return ret; > - } > + ret = mdev->fops->open(filp); > + if (ret) { > + put_device(&mdev->dev); > + return ret; > } > > + fh = filp->private_data; > + fh->devnode = mdev; > + > return 0; > } > > @@ -193,8 +193,7 @@ static int media_release(struct inode *inode, struct file *filp) > { > struct media_devnode *mdev = media_devnode_data(filp); > > - if (mdev->fops->release) > - mdev->fops->release(filp); > + mdev->fops->release(filp); > > /* decrease the refcount unconditionally since the release() > return value is ignored. */ > diff --git a/include/media/media-devnode.h b/include/media/media-devnode.h > index 17ddae32060d..ce81047cb4fc 100644 > --- a/include/media/media-devnode.h > +++ b/include/media/media-devnode.h > @@ -52,6 +52,20 @@ struct media_file_operations { > }; > > /** > + * struct media_devnode_fh - Media device node file handle > + * @devnode: pointer to the media device node > + * > + * This structure serves as a base for per-file-handle data storage. Media > + * device node users embed media_devnode_fh in their custom file handle data > + * structures and store the media_devnode_fh in the file private_data in order > + * to let the media device node core locate the media_devnode corresponding to a > + * file handle. > + */ > +struct media_devnode_fh { > + struct media_devnode *devnode; > +}; > + > +/** > * struct media_devnode - Media device node > * @fops: pointer to struct media_file_operations with media device ops > * @dev: struct device pointer for the media controller device > @@ -92,7 +106,9 @@ void media_devnode_unregister(struct media_devnode *mdev); > > static inline struct media_devnode *media_devnode_data(struct file *filp) > { > - return filp->private_data; > + struct media_devnode_fh *fh = filp->private_data; > + > + return fh->devnode; > } > > static inline int media_devnode_is_registered(struct media_devnode *mdev)
diff --git a/drivers/media/media-device.c b/drivers/media/media-device.c index 7b39440192d6..285f7d79d848 100644 --- a/drivers/media/media-device.c +++ b/drivers/media/media-device.c @@ -24,23 +24,45 @@ #include <linux/export.h> #include <linux/ioctl.h> #include <linux/media.h> +#include <linux/slab.h> #include <linux/types.h> #include <media/media-device.h> #include <media/media-devnode.h> #include <media/media-entity.h> +struct media_device_fh { + struct media_devnode_fh fh; +}; + +static inline struct media_device_fh *media_device_fh(struct file *filp) +{ + return container_of(filp->private_data, struct media_device_fh, fh); +} + /* ----------------------------------------------------------------------------- * Userspace API */ static int media_device_open(struct file *filp) { + struct media_device_fh *fh; + + fh = kzalloc(sizeof(*media_device_fh), GFP_KERNEL); + if (!fh) + return -ENOMEM; + + filp->private_data = &fh->fh; + return 0; } static int media_device_close(struct file *filp) { + struct media_device_fh *fh = media_device_fh(filp); + + kfree(fh); + return 0; } diff --git a/drivers/media/media-devnode.c b/drivers/media/media-devnode.c index ebf9626e5ae5..67bac29838d3 100644 --- a/drivers/media/media-devnode.c +++ b/drivers/media/media-devnode.c @@ -154,6 +154,7 @@ static long media_compat_ioctl(struct file *filp, unsigned int cmd, /* Override for the open function */ static int media_open(struct inode *inode, struct file *filp) { + struct media_devnode_fh *fh; struct media_devnode *mdev; int ret; @@ -175,16 +176,15 @@ static int media_open(struct inode *inode, struct file *filp) get_device(&mdev->dev); mutex_unlock(&media_devnode_lock); - filp->private_data = mdev; - - if (mdev->fops->open) { - ret = mdev->fops->open(filp); - if (ret) { - put_device(&mdev->dev); - return ret; - } + ret = mdev->fops->open(filp); + if (ret) { + put_device(&mdev->dev); + return ret; } + fh = filp->private_data; + fh->devnode = mdev; + return 0; } @@ -193,8 +193,7 @@ static int media_release(struct inode *inode, struct file *filp) { struct media_devnode *mdev = media_devnode_data(filp); - if (mdev->fops->release) - mdev->fops->release(filp); + mdev->fops->release(filp); /* decrease the refcount unconditionally since the release() return value is ignored. */ diff --git a/include/media/media-devnode.h b/include/media/media-devnode.h index 17ddae32060d..ce81047cb4fc 100644 --- a/include/media/media-devnode.h +++ b/include/media/media-devnode.h @@ -52,6 +52,20 @@ struct media_file_operations { }; /** + * struct media_devnode_fh - Media device node file handle + * @devnode: pointer to the media device node + * + * This structure serves as a base for per-file-handle data storage. Media + * device node users embed media_devnode_fh in their custom file handle data + * structures and store the media_devnode_fh in the file private_data in order + * to let the media device node core locate the media_devnode corresponding to a + * file handle. + */ +struct media_devnode_fh { + struct media_devnode *devnode; +}; + +/** * struct media_devnode - Media device node * @fops: pointer to struct media_file_operations with media device ops * @dev: struct device pointer for the media controller device @@ -92,7 +106,9 @@ void media_devnode_unregister(struct media_devnode *mdev); static inline struct media_devnode *media_devnode_data(struct file *filp) { - return filp->private_data; + struct media_devnode_fh *fh = filp->private_data; + + return fh->devnode; } static inline int media_devnode_is_registered(struct media_devnode *mdev)
The media devnode core associates devnodes with files by storing the devnode pointer in the file structure private_data field. In order to allow tracking of per-file-handle data introduce a new media devnode file handle structure that stores the devnode pointer, and store a pointer to that structure in the file private_data field. Users of the media devnode code (the only existing user being media_device) are responsible for managing their own subclass of the media_devnode_fh structure. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> --- drivers/media/media-device.c | 22 ++++++++++++++++++++++ drivers/media/media-devnode.c | 19 +++++++++---------- include/media/media-devnode.h | 18 +++++++++++++++++- 3 files changed, 48 insertions(+), 11 deletions(-)