fd.h File Reference

operation handlers More...

Include dependency graph for fd.h:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Data Structures
struct	rtdm_fd_ops
	More...

Functions
int	rtdm_open_handler (struct rtdm_fd *fd, int oflags)
	Open handler for named devices. More...
int	rtdm_socket_handler (struct rtdm_fd *fd, int protocol)
	Socket creation handler for protocol devices. More...
void	rtdm_close_handler (struct rtdm_fd *fd)
	Close handler. More...
int	rtdm_ioctl_handler (struct rtdm_fd *fd, unsigned int request, void __user *arg)
	IOCTL handler. More...
ssize_t	rtdm_read_handler (struct rtdm_fd *fd, void __user *buf, size_t size)
	Read handler. More...
ssize_t	rtdm_write_handler (struct rtdm_fd *fd, const void __user *buf, size_t size)
	Write handler. More...
ssize_t	rtdm_recvmsg_handler (struct rtdm_fd *fd, struct user_msghdr *msg, int flags)
	Receive message handler. More...
ssize_t	rtdm_sendmsg_handler (struct rtdm_fd *fd, const struct user_msghdr *msg, int flags)
	Transmit message handler. More...
int	rtdm_select_handler (struct rtdm_fd *fd, struct xnselector *selector, unsigned int type, unsigned int index)
	Select handler. More...
int	rtdm_mmap_handler (struct rtdm_fd *fd, struct vm_area_struct *vma)
	Memory mapping handler. More...
unsigned long	rtdm_get_unmapped_area_handler (struct rtdm_fd *fd, unsigned long len, unsigned long pgoff, unsigned long flags)
	Allocate mapping region in address space. More...
struct rtdm_fd *	rtdm_fd_get (int ufd, unsigned int magic)
	Retrieve and lock a RTDM file descriptor. More...
int	rtdm_fd_lock (struct rtdm_fd *fd)
	Hold a reference on a RTDM file descriptor. More...
void	rtdm_fd_put (struct rtdm_fd *fd)
	Release a RTDM file descriptor obtained via rtdm_fd_get() More...
void	rtdm_fd_unlock (struct rtdm_fd *fd)
	Drop a reference on a RTDM file descriptor. More...
int	rtdm_fd_select (int ufd, struct xnselector *selector, unsigned int type)
	Bind a selector to specified event types of a given file descriptor. More...

Detailed Description

operation handlers

Function Documentation

rtdm_fd_get()

struct rtdm_fd* rtdm_fd_get	(	int	ufd,
		unsigned int	magic
	)

Retrieve and lock a RTDM file descriptor.

Parameters

[in]	ufd	User-side file descriptor
[in]	magic	Magic word for lookup validation

Returns

Pointer to the RTDM file descriptor matching ufd. Otherwise:

• ERR_PTR(-EADV) if the use-space handle is either invalid, or not managed by RTDM.
• ERR_PTR(-EBADF) if the underlying device is being torn down at the time of the call.

Note

The file descriptor returned must be later released by a call to rtdm_fd_put().

Tags

unrestricted

rtdm_fd_lock()

int rtdm_fd_lock

(

struct rtdm_fd *

fd

)

Hold a reference on a RTDM file descriptor.

Parameters

[in]

fd

Target file descriptor

Note

rtdm_fd_lock() increments the reference counter of fd. You only need to call this function in special scenarios, e.g. when keeping additional references to the file descriptor that have different lifetimes. Only use rtdm_fd_lock() on descriptors that are currently locked via an earlier rtdm_fd_get()/rtdm_fd_lock() or while running a device operation handler.

Tags

unrestricted

rtdm_fd_put()

void rtdm_fd_put

(

struct rtdm_fd *

fd

)

Release a RTDM file descriptor obtained via rtdm_fd_get()

Parameters

[in]

fd

RTDM file descriptor to release

Note

Every call to rtdm_fd_get() must be matched by a call to rtdm_fd_put().

Tags

unrestricted

rtdm_fd_select()

int rtdm_fd_select	(	int	ufd,
		struct xnselector *	selector,
		unsigned int	type
	)

Bind a selector to specified event types of a given file descriptor.

This function is invoked by higher RTOS layers implementing select-like services. It shall not be called directly by RTDM drivers.

Parameters

[in]	ufd	User-side file descriptor to bind to
[in,out]	selector	Selector object that shall be bound to the given event
[in]	type	Event type the caller is interested in

Returns

0 on success, otherwise:

• -EADV is returned if the file descriptor ufd cannot be resolved.
• -EBADF is returned if the underlying device is being torn down at the time of the call.
• -EINVAL is returned if type is invalid.

Tags

task-unrestricted

rtdm_fd_unlock()

void rtdm_fd_unlock

(

struct rtdm_fd *

fd

)

Drop a reference on a RTDM file descriptor.

Parameters

[in]

fd

Target file descriptor

Note

Every call to rtdm_fd_lock() must be matched by a call to rtdm_fd_unlock().

Tags

unrestricted