Data Structures
struct	rtdm_fd_ops
	More...

Macros
#define	RTDM_MAX_MINOR 4096
	Maximum number of named devices per driver.

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...

int	rtdm_dev_register (struct rtdm_device *dev)
	Register a RTDM device. More...

void	rtdm_dev_unregister (struct rtdm_device *dev)
	Unregister a RTDM device. More...

int	rtdm_drv_set_sysclass (struct rtdm_driver drv, struct class cls)
	Set the kernel device class of a RTDM driver. More...

Device Flags
Static flags describing a RTDM device
#define	RTDM_EXCLUSIVE 0x0001
	If set, only a single instance of the device can be requested by an application.

#define	RTDM_FIXED_MINOR 0x0002
	Use fixed minor provided in the rtdm_device description for registering. More...

#define	RTDM_NAMED_DEVICE 0x0010
	If set, the device is addressed via a clear-text name.

#define	RTDM_PROTOCOL_DEVICE 0x0020
	If set, the device is addressed via a combination of protocol ID and socket type.

#define	RTDM_DEVICE_TYPE_MASK 0x00F0
	Mask selecting the device type.

#define	RTDM_SECURE_DEVICE 0x80000000
	Flag indicating a secure variant of RTDM (not supported here)

Detailed Description

Macro Definition Documentation

◆ RTDM_FIXED_MINOR

#define RTDM_FIXED_MINOR 0x0002

Use fixed minor provided in the rtdm_device description for registering.

If this flag is absent, the RTDM core assigns minor numbers to devices managed by a driver in order of registration.

Function Documentation

◆ rtdm_close_handler()

void rtdm_close_handler ( struct rtdm_fd * fd )

Close handler.

Parameters

[in] fd File descriptor associated with opened device instance.

See also: close() in IEEE Std 1003.1, http://www.opengroup.org/onlinepubs/009695399

◆ rtdm_dev_register()

int rtdm_dev_register ( struct rtdm_device * dev )

Register a RTDM device.

Registers a device in the RTDM namespace.

Parameters

[in] dev Device descriptor.

Returns: 0 is returned upon success. Otherwise:

-EINVAL is returned if the descriptor contains invalid entries. RTDM_PROFILE_INFO() must appear in the list of initializers for the driver properties.
-EEXIST is returned if the specified device name of protocol ID is already in use.
-ENOMEM is returned if a memory allocation failed in the process of registering the device.
-EAGAIN is returned if no registry slot is available (check/raise CONFIG_XENO_OPT_REGISTRY_NRSLOTS).
-ENOSYS is returned if the real-time core is disabled.
-ENXIO is returned if no valid minor could be assigned

Tags: secondary-only

◆ rtdm_dev_unregister()

void rtdm_dev_unregister ( struct rtdm_device * dev )

Unregister a RTDM device.

Removes the device from the RTDM namespace. This routine first attempts to teardown all active connections to the device prior to unregistering.

Parameters

[in] dev Device descriptor.

Tags: secondary-only

References rtdm_device::driver.

◆ rtdm_drv_set_sysclass()

int rtdm_drv_set_sysclass	(	struct rtdm_driver *	drv,
		struct class *	cls
	)

Set the kernel device class of a RTDM driver.

Set the kernel device class assigned to the RTDM driver. By default, RTDM drivers belong to Linux's "rtdm" device class, creating a device node hierarchy rooted at /dev/rtdm, and sysfs nodes under /sys/class/rtdm.

This call assigns a user-defined kernel device class to the RTDM driver, so that its devices are created into a different system hierarchy.

rtdm_drv_set_sysclass() is meaningful only before the first device which is attached to drv is registered by a call to rtdm_dev_register().

Parameters

[in]	drv	Address of the RTDM driver descriptor.
[in]	cls	Pointer to the kernel device class. NULL is allowed to clear a previous setting, switching back to the default "rtdm" device class.

Returns: 0 on success, otherwise:

-EBUSY is returned if the kernel device class has already been set for drv, or some device(s) attached to drv are currently registered.

Tags: task-unrestricted

Attention: The kernel device class set by this call is not related to the RTDM class identification as defined by the RTDM profiles in any way. This is strictly related to the Linux kernel device hierarchy.

References rtdm_driver::profile_info.

◆ rtdm_get_unmapped_area_handler()

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.

When present, this optional handler should return the start address of a free region in the process's address space, large enough to cover the ongoing mmap() operation. If unspecified, the default architecture-defined handler is invoked.

Most drivers can omit this handler, except on MMU-less platforms (see second note).

Parameters

[in]	fd	File descriptor
[in]	len	Length of the requested region
[in]	pgoff	Page frame number to map to (see second note).
[in]	flags	Requested mapping flags

Returns: The start address of the mapping region on success. On failure, a negative error code should be returned, with -ENOSYS meaning that the driver does not want to provide such information, in which case the ongoing mmap() operation will fail.

Note: The address hint passed to the mmap() request is deliberately ignored by RTDM, and therefore not passed to this handler.; On MMU-less platforms, this handler is required because RTDM issues mapping requests over a shareable character device internally. In such context, the RTDM core may pass a null pgoff argument to the handler, for probing for the logical start address of the memory region to map to. Otherwise, when pgoff is non-zero, pgoff << PAGE_SHIFT is usually returned.

◆ rtdm_ioctl_handler()

int rtdm_ioctl_handler	(	struct rtdm_fd *	fd,
		unsigned int	request,
		void __user *	arg
	)

IOCTL handler.

Parameters

[in]	fd	File descriptor
[in]	request	Request number as passed by the user
[in,out]	arg	Request argument as passed by the user

Returns: A positive value or 0 on success. On failure return either -ENOSYS, to request that the function be called again from the opposite realtime/non-realtime context, or another negative error code.

See also: ioctl() in IEEE Std 1003.1, http://www.opengroup.org/onlinepubs/009695399

◆ rtdm_mmap_handler()

int rtdm_mmap_handler	(	struct rtdm_fd *	fd,
		struct vm_area_struct *	vma
	)

Memory mapping handler.

Parameters

[in]	fd	File descriptor
[in]	vma	Virtual memory area descriptor

Returns: 0 on success. On failure, a negative error code is returned.

See also: mmap() in POSIX.1-2001, http://pubs.opengroup.org/onlinepubs/7908799/xsh/mmap.html

Note: The address hint passed to the mmap() request is deliberately ignored by RTDM.

◆ rtdm_open_handler()

int rtdm_open_handler	(	struct rtdm_fd *	fd,
		int	oflags
	)

Open handler for named devices.

Parameters

[in]	fd	File descriptor associated with opened device instance
[in]	oflags	Open flags as passed by the user

The file descriptor carries a device minor information which can be retrieved by a call to rtdm_fd_minor(fd). The minor number can be used for distinguishing devices managed by a driver.

Returns: 0 on success. On failure, a negative error code is returned.

See also: open() in IEEE Std 1003.1, http://www.opengroup.org/onlinepubs/009695399

◆ rtdm_read_handler()

ssize_t rtdm_read_handler	(	struct rtdm_fd *	fd,
		void __user *	buf,
		size_t	size
	)

Read handler.

Parameters

[in]	fd	File descriptor
[out]	buf	Input buffer as passed by the user
[in]	size	Number of bytes the user requests to read

Returns: On success, the number of bytes read. On failure return either -ENOSYS, to request that this handler be called again from the opposite realtime/non-realtime context, or another negative error code.

See also: read() in IEEE Std 1003.1, http://www.opengroup.org/onlinepubs/009695399

◆ rtdm_recvmsg_handler()

ssize_t rtdm_recvmsg_handler	(	struct rtdm_fd *	fd,
		struct user_msghdr *	msg,
		int	flags
	)

Receive message handler.

Parameters

[in]	fd	File descriptor
[in,out]	msg	Message descriptor as passed by the user, automatically mirrored to safe kernel memory in case of user mode call
[in]	flags	Message flags as passed by the user

Returns: On success, the number of bytes received. On failure return either -ENOSYS, to request that this handler be called again from the opposite realtime/non-realtime context, or another negative error code.

See also: recvmsg() in IEEE Std 1003.1, http://www.opengroup.org/onlinepubs/009695399

◆ rtdm_select_handler()

int rtdm_select_handler	(	struct rtdm_fd *	fd,
		struct xnselector *	selector,
		unsigned int	type,
		unsigned int	index
	)

Select handler.

Parameters

[in]	fd	File descriptor
	selector	Pointer to the selector structure
	type	Type of events (XNSELECT_READ, XNSELECT_WRITE, or XNSELECT_EXCEPT)
	index	Index of the file descriptor

Returns: 0 on success. On failure, a negative error code is returned.

See also: select() in POSIX.1-2001, http://pubs.opengroup.org/onlinepubs/007908799/xsh/select.html

◆ rtdm_sendmsg_handler()

ssize_t rtdm_sendmsg_handler	(	struct rtdm_fd *	fd,
		const struct user_msghdr *	msg,
		int	flags
	)

Transmit message handler.

Parameters

[in]	fd	File descriptor
[in]	msg	Message descriptor as passed by the user, automatically mirrored to safe kernel memory in case of user mode call
[in]	flags	Message flags as passed by the user

Returns: On success, the number of bytes transmitted. On failure return either -ENOSYS, to request that this handler be called again from the opposite realtime/non-realtime context, or another negative error code.

See also: sendmsg() in IEEE Std 1003.1, http://www.opengroup.org/onlinepubs/009695399

◆ rtdm_socket_handler()

int rtdm_socket_handler	(	struct rtdm_fd *	fd,
		int	protocol
	)

Socket creation handler for protocol devices.

Parameters

[in]	fd	File descriptor associated with opened device instance
[in]	protocol	Protocol number as passed by the user

Returns: 0 on success. On failure, a negative error code is returned.

See also: socket() in IEEE Std 1003.1, http://www.opengroup.org/onlinepubs/009695399

◆ rtdm_write_handler()

ssize_t rtdm_write_handler	(	struct rtdm_fd *	fd,
		const void __user *	buf,
		size_t	size
	)

Write handler.

Parameters

[in]	fd	File descriptor
[in]	buf	Output buffer as passed by the user
[in]	size	Number of bytes the user requests to write

Returns: On success, the number of bytes written. On failure return either -ENOSYS, to request that this handler be called again from the opposite realtime/non-realtime context, or another negative error code.

See also: write() in IEEE Std 1003.1, http://www.opengroup.org/onlinepubs/009695399

Data Structures

Macros

Functions

Device Flags

Detailed Description

Macro Definition Documentation

◆ RTDM_FIXED_MINOR

Function Documentation

◆ rtdm_close_handler()

◆ rtdm_dev_register()

◆ rtdm_dev_unregister()

◆ rtdm_drv_set_sysclass()

◆ rtdm_get_unmapped_area_handler()

◆ rtdm_ioctl_handler()

◆ rtdm_mmap_handler()

◆ rtdm_open_handler()

◆ rtdm_read_handler()

◆ rtdm_recvmsg_handler()

◆ rtdm_select_handler()

◆ rtdm_sendmsg_handler()

◆ rtdm_socket_handler()

◆ rtdm_write_handler()