mirror of
https://github.com/torvalds/linux.git
synced 2024-11-01 09:41:44 +00:00
1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
138 lines
2.8 KiB
C
138 lines
2.8 KiB
C
|
|
#include <linux/kernel.h>
|
|
#include <linux/dirent.h>
|
|
#include <linux/string.h>
|
|
|
|
#include "do_mounts.h"
|
|
|
|
void __init mount_devfs(void)
|
|
{
|
|
sys_mount("devfs", "/dev", "devfs", 0, NULL);
|
|
}
|
|
|
|
void __init umount_devfs(char *path)
|
|
{
|
|
sys_umount(path, 0);
|
|
}
|
|
|
|
/*
|
|
* If the dir will fit in *buf, return its length. If it won't fit, return
|
|
* zero. Return -ve on error.
|
|
*/
|
|
static int __init do_read_dir(int fd, void *buf, int len)
|
|
{
|
|
long bytes, n;
|
|
char *p = buf;
|
|
sys_lseek(fd, 0, 0);
|
|
|
|
for (bytes = 0; bytes < len; bytes += n) {
|
|
n = sys_getdents64(fd, (struct linux_dirent64 *)(p + bytes),
|
|
len - bytes);
|
|
if (n < 0)
|
|
return n;
|
|
if (n == 0)
|
|
return bytes;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Try to read all of a directory. Returns the contents at *p, which
|
|
* is kmalloced memory. Returns the number of bytes read at *len. Returns
|
|
* NULL on error.
|
|
*/
|
|
static void * __init read_dir(char *path, int *len)
|
|
{
|
|
int size;
|
|
int fd = sys_open(path, 0, 0);
|
|
|
|
*len = 0;
|
|
if (fd < 0)
|
|
return NULL;
|
|
|
|
for (size = 1 << 9; size <= (PAGE_SIZE << MAX_ORDER); size <<= 1) {
|
|
void *p = kmalloc(size, GFP_KERNEL);
|
|
int n;
|
|
if (!p)
|
|
break;
|
|
n = do_read_dir(fd, p, size);
|
|
if (n > 0) {
|
|
sys_close(fd);
|
|
*len = n;
|
|
return p;
|
|
}
|
|
kfree(p);
|
|
if (n == -EINVAL)
|
|
continue; /* Try a larger buffer */
|
|
if (n < 0)
|
|
break;
|
|
}
|
|
sys_close(fd);
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* recursively scan <path>, looking for a device node of type <dev>
|
|
*/
|
|
static int __init find_in_devfs(char *path, unsigned dev)
|
|
{
|
|
char *end = path + strlen(path);
|
|
int rest = path + 64 - end;
|
|
int size;
|
|
char *p = read_dir(path, &size);
|
|
char *s;
|
|
|
|
if (!p)
|
|
return -1;
|
|
for (s = p; s < p + size; s += ((struct linux_dirent64 *)s)->d_reclen) {
|
|
struct linux_dirent64 *d = (struct linux_dirent64 *)s;
|
|
if (strlen(d->d_name) + 2 > rest)
|
|
continue;
|
|
switch (d->d_type) {
|
|
case DT_BLK:
|
|
sprintf(end, "/%s", d->d_name);
|
|
if (bstat(path) != dev)
|
|
break;
|
|
kfree(p);
|
|
return 0;
|
|
case DT_DIR:
|
|
if (strcmp(d->d_name, ".") == 0)
|
|
break;
|
|
if (strcmp(d->d_name, "..") == 0)
|
|
break;
|
|
sprintf(end, "/%s", d->d_name);
|
|
if (find_in_devfs(path, dev) < 0)
|
|
break;
|
|
kfree(p);
|
|
return 0;
|
|
}
|
|
}
|
|
kfree(p);
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* create a device node called <name> which points to
|
|
* <devfs_name> if possible, otherwise find a device node
|
|
* which matches <dev> and make <name> a symlink pointing to it.
|
|
*/
|
|
int __init create_dev(char *name, dev_t dev, char *devfs_name)
|
|
{
|
|
char path[64];
|
|
|
|
sys_unlink(name);
|
|
if (devfs_name && devfs_name[0]) {
|
|
if (strncmp(devfs_name, "/dev/", 5) == 0)
|
|
devfs_name += 5;
|
|
sprintf(path, "/dev/%s", devfs_name);
|
|
if (sys_access(path, 0) == 0)
|
|
return sys_symlink(devfs_name, name);
|
|
}
|
|
if (!dev)
|
|
return -1;
|
|
strcpy(path, "/dev");
|
|
if (find_in_devfs(path, new_encode_dev(dev)) < 0)
|
|
return -1;
|
|
return sys_symlink(path + 5, name);
|
|
}
|