dev.h File Reference

#include <core/system.h>
#include <mm/vm.h>
#include <fs/vfs.h>
#include <sys/proc.h>
#include <fs/iobuf.h>

Go to the source code of this file.

Data Structures
struct	devid
	Which device: its kind (S_IFCHR or S_IFBLK) and numbers. More...
struct	dev
	A device driver: its operations, any of which may be NULL. More...

Macros
#define	DEV(major, minor)
#define	DEV_MAJOR(dev)
#define	DEV_MINOR(dev)
#define	VNODE_DEV(vnode)

Functions
void	kdev_init (void)
	Starts the device layer, at boot.
void	kdev_chrdev_register (devid_t major, struct dev *dev)
	Registers a driver as the character device of a major number.
void	kdev_blkdev_register (devid_t major, struct dev *dev)
	Registers a driver as the block device of a major number.
int	kdev_sync (void)
	Writes what the block cache holds that was written, and what the block devices hold in their write caches, to the media.
ssize_t	kdev_read (struct devid *dd, off_t offset, struct iobuf *io)
	Reads from a device: a character device through its driver, a block device in blocks.
ssize_t	kdev_write (struct devid *dd, off_t offset, struct iobuf *io)
	Writes to a device: a character device through its driver, a block device in blocks.
int	kdev_ioctl (struct devid *dd, int request, void *argp)
	Passes an ioctl() to a device's driver.
int	kdev_map (struct devid *dd, struct vm_space *vm_space, struct vm_entry *vm_entry)
	Maps a device into an address space (mmap() of a framebuffer).
struct fops *	kdev_fops (struct devid *dd)
	Returns the file operations of a device.
int	kdev_file_open (struct devid *dd, struct file *file)
	Opens a device, through its driver's file operations.
ssize_t	kdev_file_read (struct devid *dd, struct file *file, struct iobuf *io)
	Reads an open device file, through its driver's file operations.
ssize_t	kdev_file_write (struct devid *dd, struct file *file, struct iobuf *io)
	Writes to an open device file, through its driver's file operations.
off_t	kdev_file_lseek (struct devid *dd, struct file *file, off_t offset, int whence)
	Moves an open device file's offset, through its driver's file operations.
ssize_t	kdev_file_close (struct devid *dd, struct file *file)
	Closes an open device file, through its driver's file operations.
int	kdev_file_ioctl (struct devid *dd, struct file *file, int request, void *argp)
	Passes an ioctl() on an open device file to its driver's file operations.
int	kdev_file_can_read (struct devid *dd, struct file *file, size_t size)
	Asks a device's driver whether a read wouldn't have to wait.
int	kdev_file_can_write (struct devid *dd, struct file *file, size_t size)
	Asks a device's driver whether a write wouldn't have to wait.
int	kdev_file_eof (struct devid *dd, struct file *file)
	Asks a device's driver whether a read that found no data is at the end of the file.

Variables
struct dev	ttydev
struct dev	pcidev
struct dev	atadev
struct dev	fbdev
struct dev	rddev

Macro Definition Documentation

DEV

#define DEV	(		major,
			minor )

Value:

((dev_t)(((major) & 0xFF) << 8) | ((minor) & 0xFF))

Definition at line 76 of file dev.h.

Referenced by ext2_inode_build(), ext2_vmknod(), kmain(), load_ramdisk(), minix_vmknod(), ptm_new(), pts_new(), root_dev(), and tty_open().

DEV_MAJOR

#define DEV_MAJOR

(

dev

)

Value:

((devid_t)(((dev) >> 8) & 0xFF))

Definition at line 77 of file dev.h.

Referenced by ext2_vmknod(), minix_vmknod(), vt_file_close(), and vt_file_open().

DEV_MINOR

#define DEV_MINOR

(

dev

)

Value:

((devid_t)(((dev) >> 0) & 0xFF))

Definition at line 78 of file dev.h.

Referenced by ext2_vmknod(), minix_vmknod(), uart_can_read(), uart_file_eof(), uart_file_open(), uart_read_timeout(), vt_file_close(), and vt_file_open().

VNODE_DEV

#define VNODE_DEV

(

vnode

)

Value:

((struct devid){.type = (vnode)->mode & S_IFMT, .major = DEV_MAJOR((vnode)->rdev), .minor = DEV_MINOR((vnode)->rdev)})

Definition at line 79 of file dev.h.

Referenced by ctty_open(), posix_file_read(), ptm_can_read(), pts_can_read(), pts_eof(), pts_open(), pts_read_timeout(), vfs_file_can_read(), vfs_file_can_write(), vfs_file_close(), vfs_file_eof(), vfs_file_ioctl(), vfs_file_lseek(), vfs_file_open(), vfs_file_read(), vfs_file_write(), vfs_ioctl(), vfs_map(), vfs_read_io(), vfs_write_io(), and vt_file().

Function Documentation

kdev_blkdev_register()

void kdev_blkdev_register	(	devid_t	major,
		struct dev *	dev )

Registers a driver as the block device of a major number.

A driver registered before for that major is replaced.

Parameters

major	the major number
dev	the driver

Definition at line 605 of file kdev.c.

References blkdev, kdev_blkdev_register(), dev::name, and printk().

Referenced by ata_probe(), kdev_blkdev_register(), and rd_probe().

kdev_chrdev_register()

void kdev_chrdev_register	(	devid_t	major,
		struct dev *	dev )

Registers a driver as the character device of a major number.

A driver registered before for that major is replaced.

Parameters

major	the major number
dev	the driver

Definition at line 575 of file kdev.c.

References chrdev, kdev_chrdev_register(), dev::name, and printk().

Referenced by fbdev_probe(), kdev_chrdev_register(), memdev_probe(), ps2mouse_probe(), pty_init(), ttydev_probe(), and vt_probe().

kdev_file_can_read()

int kdev_file_can_read	(	struct devid *	dd,
		struct file *	file,
		size_t	size )

Asks a device's driver whether a read wouldn't have to wait.

Parameters

dd	the device's number
file	the open file
size	how much would be read

Returns

whether it can be read, or a negative errno

Definition at line 513 of file kdev.c.

References fops::can_read, dev::fops, kdev_file_can_read(), kdev_get(), and NULL.

Referenced by kdev_file_can_read(), and vfs_file_can_read().

kdev_file_can_write()

int kdev_file_can_write	(	struct devid *	dd,
		struct file *	file,
		size_t	size )

Asks a device's driver whether a write wouldn't have to wait.

Parameters

dd	the device's number
file	the open file
size	how much would be written

Returns

whether it can be written, or a negative errno

Definition at line 534 of file kdev.c.

References fops::can_write, dev::fops, kdev_file_can_write(), kdev_get(), and NULL.

Referenced by kdev_file_can_write(), and vfs_file_can_write().

kdev_file_close()

ssize_t kdev_file_close	(	struct devid *	dd,
		struct file *	file )

Closes an open device file, through its driver's file operations.

Parameters

dd	the device's number
file	the open file

Returns

0, or a negative errno

Definition at line 468 of file kdev.c.

References fops::close, dev::fops, kdev_file_close(), kdev_get(), NULL, and posix_file_close().

Referenced by kdev_file_close(), and vfs_file_close().

kdev_file_eof()

int kdev_file_eof	(	struct devid *	dd,
		struct file *	file )

Asks a device's driver whether a read that found no data is at the end of the file.

Parameters

dd	the device's number
file	the open file

Returns

whether it is, or a negative errno

Definition at line 555 of file kdev.c.

References fops::eof, dev::fops, kdev_file_eof(), kdev_get(), and NULL.

Referenced by kdev_file_eof(), and vfs_file_eof().

kdev_file_ioctl()

int kdev_file_ioctl	(	struct devid *	dd,
		struct file *	file,
		int	request,
		void *	argp )

Passes an ioctl() on an open device file to its driver's file operations.

Parameters

dd	the device's number
file	the open file
request	the request
argp	its argument

Returns

what the driver returns, or a negative errno

Definition at line 492 of file kdev.c.

References dev::fops, fops::ioctl, kdev_file_ioctl(), kdev_get(), and NULL.

Referenced by kdev_file_ioctl(), and vfs_file_ioctl().

kdev_file_lseek()

off_t kdev_file_lseek	(	struct devid *	dd,
		struct file *	file,
		off_t	offset,
		int	whence )

Moves an open device file's offset, through its driver's file operations.

Parameters

dd	the device's number
file	the open file
offset	the offset
whence	what it is from (SEEK_SET, SEEK_CUR, SEEK_END)

Returns

the new offset, or a negative errno (-ESPIPE for a device that can't seek)

Definition at line 447 of file kdev.c.

References dev::fops, kdev_file_lseek(), kdev_get(), fops::lseek, and NULL.

Referenced by kdev_file_lseek(), and vfs_file_lseek().

kdev_file_open()

int kdev_file_open	(	struct devid *	dd,
		struct file *	file )

Opens a device, through its driver's file operations.

Parameters

dd	the device's number
file	the open file

Returns

0, or a negative errno (-ENXIO if there is no such device)

Definition at line 381 of file kdev.c.

References dev::fops, kdev_file_open(), kdev_get(), NULL, and fops::open.

Referenced by ctty_open(), kdev_file_open(), and vfs_file_open().

kdev_file_read()

ssize_t kdev_file_read	(	struct devid *	dd,
		struct file *	file,
		struct iobuf *	io )

Reads an open device file, through its driver's file operations.

Parameters

dd	the device's number
file	the open file
io	where to put what is read

Returns

how many bytes were read, or a negative errno

Definition at line 402 of file kdev.c.

References dev::fops, kdev_file_read(), kdev_get(), NULL, and fops::read.

Referenced by kdev_file_read(), and vfs_file_read().

kdev_file_write()

ssize_t kdev_file_write	(	struct devid *	dd,
		struct file *	file,
		struct iobuf *	io )

Writes to an open device file, through its driver's file operations.

Parameters

dd	the device's number
file	the open file
io	what to write

Returns

how many bytes were written, or a negative errno

Definition at line 423 of file kdev.c.

References dev::fops, kdev_file_write(), kdev_get(), NULL, and fops::write.

Referenced by kdev_file_write(), and vfs_file_write().

kdev_fops()

struct fops * kdev_fops

(

struct devid *

dd

)

Returns the file operations of a device.

Parameters

dd	the device's number

Returns

its file operations, or NULL if there is no such device

Definition at line 52 of file kdev.c.

References dev::fops, kdev_fops(), kdev_get(), and NULL.

Referenced by kdev_fops(), and posix_file_read().

kdev_init()

void kdev_init

(

void

)

Starts the device layer, at boot.

It has nothing to set up: the drivers register themselves.

Definition at line 615 of file kdev.c.

References kdev_init(), and printk().

Referenced by kdev_init(), and kmain().

kdev_ioctl()

int kdev_ioctl	(	struct devid *	dd,
		int	request,
		void *	argp )

Passes an ioctl() to a device's driver.

Parameters

dd	the device's number
request	the request
argp	its argument

Returns

what the driver returns, or -ENXIO if it takes no ioctl()

Definition at line 340 of file kdev.c.

References dev::ioctl, kdev_get(), kdev_ioctl(), and NULL.

Referenced by kdev_ioctl(), and vfs_ioctl().

kdev_map()

int kdev_map	(	struct devid *	dd,
		struct vm_space *	vm_space,
		struct vm_entry *	vm_entry )

Maps a device into an address space (mmap() of a framebuffer).

Parameters

dd	the device's number
vm_space	the address space
vm_entry	the mapping

Returns

0, or a negative errno (-ENXIO if the device can't be mapped)

Definition at line 361 of file kdev.c.

References kdev_get(), kdev_map(), dev::map, and NULL.

Referenced by kdev_map(), and vfs_map().

kdev_read()

ssize_t kdev_read	(	struct devid *	dd,
		off_t	offset,
		struct iobuf *	io )

Reads from a device: a character device through its driver, a block device in blocks.

Parameters

dd	the device's number
offset	where to read from, in bytes
io	where to put what is read

Returns

how many bytes were read, or a negative errno

Definition at line 297 of file kdev.c.

References dev::bread, kdev_blk_io(), kdev_get(), kdev_read(), NULL, dev::read, and devid::type.

Referenced by kdev_read(), and vfs_read_io().

kdev_sync()

int kdev_sync

(

void

)

Writes what the block cache holds that was written, and what the block devices hold in their write caches, to the media.

Returns

0, or a negative errno if a write failed

Definition at line 587 of file kdev.c.

References blkcache_flush(), blkdev, kdev_sync(), and dev::sync.

Referenced by kdev_sync(), kernel_reboot(), and sys_sync().

kdev_write()

ssize_t kdev_write	(	struct devid *	dd,
		off_t	offset,
		struct iobuf *	io )

Writes to a device: a character device through its driver, a block device in blocks.

Parameters

dd	the device's number
offset	where to write, in bytes
io	what to write

Returns

how many bytes were written, or a negative errno

Definition at line 319 of file kdev.c.

References dev::bwrite, kdev_blk_io(), kdev_get(), kdev_write(), NULL, devid::type, and dev::write.

Referenced by kdev_write(), and vfs_write_io().

Variable Documentation

atadev

struct dev atadev

extern

Definition at line 592 of file ata.c.

Referenced by ata_probe().

fbdev

struct dev fbdev

extern

Definition at line 167 of file fbdev.c.

pcidev

struct dev pcidev

extern

Definition at line 225 of file pci.c.

rddev

struct dev rddev

extern

Definition at line 93 of file ramdisk.c.

ttydev

struct dev ttydev

extern

Definition at line 121 of file tty.c.