read.c File Reference

Reading from a vnode: from its device, or through its filesystem. More...

#include <core/system.h>
#include <fs/vfs.h>
#include <fs/iobuf.h>
#include <dev/dev.h>

Go to the source code of this file.

Functions
ssize_t	vfs_read_io (struct vnode *vnode, off_t off, struct iobuf *io)
	Reads from a vnode into an iobuf (user or kernel memory).
ssize_t	vfs_read (struct vnode *vnode, off_t off, size_t size, void *buf)
	Reads from a vnode into a kernel buffer.

Detailed Description

Reading from a vnode: from its device, or through its filesystem.

Definition in file read.c.

Function Documentation

vfs_read()

ssize_t vfs_read	(	struct vnode *	vnode,
		off_t	off,
		size_t	size,
		void *	buf )

Reads from a vnode into a kernel buffer.

Parameters

vnode	the vnode
off	where to read from
size	how many bytes to read
buf	the buffer

Returns

the number of bytes read, or a negative errno

Definition at line 52 of file read.c.

References iobuf_init(), vfs_read(), and vfs_read_io().

Referenced by binfmt_elf_check(), binfmt_elf_load_segments(), cpio_load(), exec_script(), ext2_io(), ext2_load(), link_path(), minix_block_read(), minix_inode_read(), minix_load(), vfs_read(), vfs_readlink(), vnode_page_in(), and vnode_pages_update().

vfs_read_io()

ssize_t vfs_read_io	(	struct vnode *	vnode,
		off_t	off,
		struct iobuf *	io )

Reads from a vnode into an iobuf (user or kernel memory).

Parameters

vnode	the vnode
off	where to read from
io	where the data goes, and how much is wanted

Returns

the number of bytes read, -EINVAL for an invalid vnode, -ENOSYS if its filesystem can't read, or another negative errno

Definition at line 20 of file read.c.

References vnode::fs, ISDEV, kdev_read(), LOG_DEBUG, vops::read, iobuf::resid, vfs_read_io(), VNODE_DEV, and fs::vops.

Referenced by cpio_read(), posix_file_read(), vfs_read(), and vfs_read_io().