[net-next 3/3] eventpoll: Add epoll ioctl for epoll_params
From: Joe Damato <hidden>
Date: 2024-01-24 02:54:29
Also in:
lkml, netdev
Subsystem:
documentation, filesystems (vfs and infrastructure), the rest · Maintainers:
Jonathan Corbet, Alexander Viro, Christian Brauner, Linus Torvalds
Add an ioctl for getting and setting epoll_params. User programs can use this ioctl to get and set the busy poll usec time or packet budget params for a specific epoll context. Signed-off-by: Joe Damato <redacted> --- .../userspace-api/ioctl/ioctl-number.rst | 1 + fs/eventpoll.c | 41 +++++++++++++++++++ include/uapi/linux/eventpoll.h | 12 ++++++ 3 files changed, 54 insertions(+)
diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst b/Documentation/userspace-api/ioctl/ioctl-number.rst
index 457e16f06e04..b33918232f78 100644
--- a/Documentation/userspace-api/ioctl/ioctl-number.rst
+++ b/Documentation/userspace-api/ioctl/ioctl-number.rst@@ -309,6 +309,7 @@ Code Seq# Include File Comments 0x89 0B-DF linux/sockios.h 0x89 E0-EF linux/sockios.h SIOCPROTOPRIVATE range 0x89 F0-FF linux/sockios.h SIOCDEVPRIVATE range +0x8A 00-1F linux/eventpoll.h 0x8B all linux/wireless.h 0x8C 00-3F WiNRADiO driver <http://www.winradio.com.au/>
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 40bd97477b91..d973147c015c 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c@@ -869,6 +869,45 @@ static void ep_clear_and_put(struct eventpoll *ep) ep_free(ep); } +static long ep_eventpoll_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + int ret; + struct eventpoll *ep; + struct epoll_params epoll_params; + void __user *uarg = (void __user *) arg; + + if (!is_file_epoll(file)) + return -EINVAL; + + ep = file->private_data; + + switch (cmd) { +#ifdef CONFIG_NET_RX_BUSY_POLL + case EPIOCSPARAMS: + if (copy_from_user(&epoll_params, uarg, sizeof(epoll_params))) + return -EFAULT; + + ep->busy_poll_usecs = epoll_params.busy_poll_usecs; + ep->busy_poll_budget = epoll_params.busy_poll_budget; + return 0; + + case EPIOCGPARAMS: + memset(&epoll_params, 0, sizeof(epoll_params)); + epoll_params.busy_poll_usecs = ep->busy_poll_usecs; + epoll_params.busy_poll_budget = ep->busy_poll_budget; + if (copy_to_user(uarg, &epoll_params, sizeof(epoll_params))) + return -EFAULT; + + return 0; +#endif + default: + ret = -EINVAL; + break; + } + + return ret; +} + static int ep_eventpoll_release(struct inode *inode, struct file *file) { struct eventpoll *ep = file->private_data;
@@ -975,6 +1014,8 @@ static const struct file_operations eventpoll_fops = { .release = ep_eventpoll_release, .poll = ep_eventpoll_poll, .llseek = noop_llseek, + .unlocked_ioctl = ep_eventpoll_ioctl, + .compat_ioctl = compat_ptr_ioctl, }; /*
diff --git a/include/uapi/linux/eventpoll.h b/include/uapi/linux/eventpoll.h
index cfbcc4cc49ac..9211103779c4 100644
--- a/include/uapi/linux/eventpoll.h
+++ b/include/uapi/linux/eventpoll.h@@ -85,4 +85,16 @@ struct epoll_event { __u64 data; } EPOLL_PACKED; +struct epoll_params { + u64 busy_poll_usecs; + u16 busy_poll_budget; + + /* for future fields */ + uint8_t data[118]; +} EPOLL_PACKED; + +#define EPOLL_IOC_TYPE 0x8A +#define EPIOCSPARAMS _IOW(EPOLL_IOC_TYPE, 0x01, struct epoll_params) +#define EPIOCGPARAMS _IOR(EPOLL_IOC_TYPE, 0x02, struct epoll_params) + #endif /* _UAPI_LINUX_EVENTPOLL_H */
--
2.25.1