#include <defs.h>
|
|
#include <string.h>
|
|
#include <stat.h>
|
|
#include <dev.h>
|
|
#include <inode.h>
|
|
#include <unistd.h>
|
|
#include <error.h>
|
|
|
|
/*
|
|
* dev_open - Called for each open().
|
|
*/
|
|
static int
|
|
dev_open(struct inode *node, uint32_t open_flags) {
|
|
if (open_flags & (O_CREAT | O_TRUNC | O_EXCL | O_APPEND)) {
|
|
return -E_INVAL;
|
|
}
|
|
struct device *dev = vop_info(node, device);
|
|
return dop_open(dev, open_flags);
|
|
}
|
|
|
|
/*
|
|
* dev_close - Called on the last close(). Just pass through.
|
|
*/
|
|
static int
|
|
dev_close(struct inode *node) {
|
|
struct device *dev = vop_info(node, device);
|
|
return dop_close(dev);
|
|
}
|
|
|
|
/*
|
|
* dev_read -Called for read. Hand off to iobuf.
|
|
*/
|
|
static int
|
|
dev_read(struct inode *node, struct iobuf *iob) {
|
|
struct device *dev = vop_info(node, device);
|
|
return dop_io(dev, iob, 0);
|
|
}
|
|
|
|
/*
|
|
* dev_write -Called for write. Hand off to iobuf.
|
|
*/
|
|
static int
|
|
dev_write(struct inode *node, struct iobuf *iob) {
|
|
struct device *dev = vop_info(node, device);
|
|
return dop_io(dev, iob, 1);
|
|
}
|
|
|
|
/*
|
|
* dev_ioctl - Called for ioctl(). Just pass through.
|
|
*/
|
|
static int
|
|
dev_ioctl(struct inode *node, int op, void *data) {
|
|
struct device *dev = vop_info(node, device);
|
|
return dop_ioctl(dev, op, data);
|
|
}
|
|
|
|
/*
|
|
* dev_fstat - Called for stat().
|
|
* Set the type and the size (block devices only).
|
|
* The link count for a device is always 1.
|
|
*/
|
|
static int
|
|
dev_fstat(struct inode *node, struct stat *stat) {
|
|
int ret;
|
|
memset(stat, 0, sizeof(struct stat));
|
|
if ((ret = vop_gettype(node, &(stat->st_mode))) != 0) {
|
|
return ret;
|
|
}
|
|
struct device *dev = vop_info(node, device);
|
|
stat->st_nlinks = 1;
|
|
stat->st_blocks = dev->d_blocks;
|
|
stat->st_size = stat->st_blocks * dev->d_blocksize;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* dev_gettype - Return the type. A device is a "block device" if it has a known
|
|
* length. A device that generates data in a stream is a "character
|
|
* device".
|
|
*/
|
|
static int
|
|
dev_gettype(struct inode *node, uint32_t *type_store) {
|
|
struct device *dev = vop_info(node, device);
|
|
*type_store = (dev->d_blocks > 0) ? S_IFBLK : S_IFCHR;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* dev_tryseek - Attempt a seek.
|
|
* For block devices, require block alignment.
|
|
* For character devices, prohibit seeking entirely.
|
|
*/
|
|
static int
|
|
dev_tryseek(struct inode *node, off_t pos) {
|
|
struct device *dev = vop_info(node, device);
|
|
if (dev->d_blocks > 0) {
|
|
if ((pos % dev->d_blocksize) == 0) {
|
|
if (pos >= 0 && pos < dev->d_blocks * dev->d_blocksize) {
|
|
return 0;
|
|
}
|
|
}
|
|
}
|
|
return -E_INVAL;
|
|
}
|
|
|
|
/*
|
|
* dev_lookup - Name lookup.
|
|
*
|
|
* One interesting feature of device:name pathname syntax is that you
|
|
* can implement pathnames on arbitrary devices. For instance, if you
|
|
* had a graphics device that supported multiple resolutions (which we
|
|
* don't), you might arrange things so that you could open it with
|
|
* pathnames like "video:800x600/24bpp" in order to select the operating
|
|
* mode.
|
|
*
|
|
* However, we have no support for this in the base system.
|
|
*/
|
|
static int
|
|
dev_lookup(struct inode *node, char *path, struct inode **node_store) {
|
|
if (*path != '\0') {
|
|
return -E_NOENT;
|
|
}
|
|
vop_ref_inc(node);
|
|
*node_store = node;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Function table for device inodes.
|
|
*/
|
|
static const struct inode_ops dev_node_ops = {
|
|
.vop_magic = VOP_MAGIC,
|
|
.vop_open = dev_open,
|
|
.vop_close = dev_close,
|
|
.vop_read = dev_read,
|
|
.vop_write = dev_write,
|
|
.vop_fstat = dev_fstat,
|
|
.vop_ioctl = dev_ioctl,
|
|
.vop_gettype = dev_gettype,
|
|
.vop_tryseek = dev_tryseek,
|
|
.vop_lookup = dev_lookup,
|
|
};
|
|
|
|
#define init_device(x) \
|
|
do { \
|
|
extern void dev_init_##x(void); \
|
|
dev_init_##x(); \
|
|
} while (0)
|
|
|
|
/* dev_init - Initialization functions for builtin vfs-level devices. */
|
|
void
|
|
dev_init(void) {
|
|
// init_device(null);
|
|
init_device(stdin);
|
|
init_device(stdout);
|
|
init_device(disk0);
|
|
}
|
|
/* dev_create_inode - Create inode for a vfs-level device. */
|
|
struct inode *
|
|
dev_create_inode(void) {
|
|
struct inode *node;
|
|
if ((node = alloc_inode(device)) != NULL) {
|
|
vop_init(node, &dev_node_ops, NULL);
|
|
}
|
|
return node;
|
|
}
|
|
|