Introduce new eptdev abstraction based on anonymous inode. The new API is exactly same with legacy one except:
- It's anonymous and devnode/path free. - Its fops->open() is empty. Signed-off-by: Dawei Li <dawei...@linux.dev> --- drivers/rpmsg/rpmsg_char.c | 49 ++++++++++++++++++++++++++++++++++++++ drivers/rpmsg/rpmsg_char.h | 23 ++++++++++++++++++ 2 files changed, 72 insertions(+) diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c index 6c19f2146698..babc63cc4238 100644 --- a/drivers/rpmsg/rpmsg_char.c +++ b/drivers/rpmsg/rpmsg_char.c @@ -13,6 +13,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include <linux/anon_inodes.h> #include <linux/cdev.h> #include <linux/device.h> #include <linux/fs.h> @@ -517,6 +518,54 @@ int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent } EXPORT_SYMBOL(rpmsg_chrdev_eptdev_create); +static const struct file_operations rpmsg_anonymous_eptdev_fops = { + .owner = THIS_MODULE, + .release = rpmsg_eptdev_release, + .read_iter = rpmsg_eptdev_read_iter, + .write_iter = rpmsg_eptdev_write_iter, + .poll = rpmsg_eptdev_poll, + .unlocked_ioctl = rpmsg_eptdev_ioctl, + .compat_ioctl = compat_ptr_ioctl, +}; + +int rpmsg_anonymous_eptdev_create(struct rpmsg_device *rpdev, struct device *parent, + struct rpmsg_channel_info chinfo, unsigned int flags, + int *pfd) +{ + struct rpmsg_eptdev *eptdev; + int ret, fd; + + /* Anonymous inode only supports these file flags */ + if (flags & ~(O_ACCMODE | O_NONBLOCK | O_CLOEXEC)) + return -EINVAL; + + eptdev = rpmsg_eptdev_alloc(rpdev, parent, false); + if (IS_ERR(eptdev)) + return PTR_ERR(eptdev); + + ret = rpmsg_eptdev_add(eptdev, chinfo, false); + if (ret) { + dev_err(&eptdev->dev, "failed to add %s\n", eptdev->chinfo.name); + return ret; + } + + fd = anon_inode_getfd("rpmsg-eptdev", &rpmsg_anonymous_eptdev_fops, eptdev, flags); + if (fd < 0) { + put_device(&eptdev->dev); + return fd; + } + + mutex_lock(&eptdev->ept_lock); + ret = __rpmsg_eptdev_open(eptdev); + mutex_unlock(&eptdev->ept_lock); + + if (!ret) + *pfd = fd; + + return ret; +} +EXPORT_SYMBOL(rpmsg_anonymous_eptdev_create); + static int rpmsg_chrdev_probe(struct rpmsg_device *rpdev) { struct rpmsg_channel_info chinfo; diff --git a/drivers/rpmsg/rpmsg_char.h b/drivers/rpmsg/rpmsg_char.h index 117d9cbc52f0..70ce2c511f13 100644 --- a/drivers/rpmsg/rpmsg_char.h +++ b/drivers/rpmsg/rpmsg_char.h @@ -19,6 +19,22 @@ int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent, struct rpmsg_channel_info chinfo); +/** + * rpmsg_anonymous_eptdev_create() - register anonymous device and its associated + * fd based on an endpoint + * @rpdev: prepared rpdev to be used for creating endpoints + * @parent: parent device + * @chinfo: associated endpoint channel information. + * @flag: file flag + * @pfd: fd in represent of endpoint device + * + * This function create a new rpmsg endpoint device and its associated fd to instantiate a new + * endpoint based on chinfo information. + */ +int rpmsg_anonymous_eptdev_create(struct rpmsg_device *rpdev, struct device *parent, + struct rpmsg_channel_info chinfo, unsigned int flags, + int *pfd); + /** * rpmsg_chrdev_eptdev_destroy() - destroy created char device endpoint. * @data: private data associated to the endpoint device @@ -36,6 +52,13 @@ static inline int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct return -ENXIO; } +static inline int rpmsg_anonymous_eptdev_create(struct rpmsg_device *rpdev, struct device *parent, + struct rpmsg_channel_info chinfo, + unsigned int flags, int *pfd) +{ + return -ENXIO; +} + static inline int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data) { return -ENXIO; -- 2.25.1