e90dae1f58
The new ioctl code passes the wrong file pointer to the underlying device. No file pointer is available so make a temporary fake one. ioctl_by_bdev() does set_fs(KERNEL_DS) so it's for ioctls originating within the kernel and unsuitable here. We are processing ioctls that originated in userspace and mapping them to different devices. Fixing the existing callers that pass a NULL file struct and consolidating the fake_file users are separate matters to solve in later patches. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
144 lines
2.9 KiB
C
144 lines
2.9 KiB
C
/*
|
|
* Copyright (C) 2001-2003 Sistina Software (UK) Limited.
|
|
*
|
|
* This file is released under the GPL.
|
|
*/
|
|
|
|
#include "dm.h"
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/init.h>
|
|
#include <linux/blkdev.h>
|
|
#include <linux/bio.h>
|
|
#include <linux/slab.h>
|
|
|
|
#define DM_MSG_PREFIX "linear"
|
|
|
|
/*
|
|
* Linear: maps a linear range of a device.
|
|
*/
|
|
struct linear_c {
|
|
struct dm_dev *dev;
|
|
sector_t start;
|
|
};
|
|
|
|
/*
|
|
* Construct a linear mapping: <dev_path> <offset>
|
|
*/
|
|
static int linear_ctr(struct dm_target *ti, unsigned int argc, char **argv)
|
|
{
|
|
struct linear_c *lc;
|
|
unsigned long long tmp;
|
|
|
|
if (argc != 2) {
|
|
ti->error = "Invalid argument count";
|
|
return -EINVAL;
|
|
}
|
|
|
|
lc = kmalloc(sizeof(*lc), GFP_KERNEL);
|
|
if (lc == NULL) {
|
|
ti->error = "dm-linear: Cannot allocate linear context";
|
|
return -ENOMEM;
|
|
}
|
|
|
|
if (sscanf(argv[1], "%llu", &tmp) != 1) {
|
|
ti->error = "dm-linear: Invalid device sector";
|
|
goto bad;
|
|
}
|
|
lc->start = tmp;
|
|
|
|
if (dm_get_device(ti, argv[0], lc->start, ti->len,
|
|
dm_table_get_mode(ti->table), &lc->dev)) {
|
|
ti->error = "dm-linear: Device lookup failed";
|
|
goto bad;
|
|
}
|
|
|
|
ti->private = lc;
|
|
return 0;
|
|
|
|
bad:
|
|
kfree(lc);
|
|
return -EINVAL;
|
|
}
|
|
|
|
static void linear_dtr(struct dm_target *ti)
|
|
{
|
|
struct linear_c *lc = (struct linear_c *) ti->private;
|
|
|
|
dm_put_device(ti, lc->dev);
|
|
kfree(lc);
|
|
}
|
|
|
|
static int linear_map(struct dm_target *ti, struct bio *bio,
|
|
union map_info *map_context)
|
|
{
|
|
struct linear_c *lc = (struct linear_c *) ti->private;
|
|
|
|
bio->bi_bdev = lc->dev->bdev;
|
|
bio->bi_sector = lc->start + (bio->bi_sector - ti->begin);
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int linear_status(struct dm_target *ti, status_type_t type,
|
|
char *result, unsigned int maxlen)
|
|
{
|
|
struct linear_c *lc = (struct linear_c *) ti->private;
|
|
|
|
switch (type) {
|
|
case STATUSTYPE_INFO:
|
|
result[0] = '\0';
|
|
break;
|
|
|
|
case STATUSTYPE_TABLE:
|
|
snprintf(result, maxlen, "%s %llu", lc->dev->name,
|
|
(unsigned long long)lc->start);
|
|
break;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int linear_ioctl(struct dm_target *ti, struct inode *inode,
|
|
struct file *filp, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
struct linear_c *lc = (struct linear_c *) ti->private;
|
|
struct block_device *bdev = lc->dev->bdev;
|
|
struct file fake_file = {};
|
|
struct dentry fake_dentry = {};
|
|
|
|
fake_file.f_mode = lc->dev->mode;
|
|
fake_file.f_dentry = &fake_dentry;
|
|
fake_dentry.d_inode = bdev->bd_inode;
|
|
|
|
return blkdev_driver_ioctl(bdev->bd_inode, &fake_file, bdev->bd_disk, cmd, arg);
|
|
}
|
|
|
|
static struct target_type linear_target = {
|
|
.name = "linear",
|
|
.version= {1, 0, 2},
|
|
.module = THIS_MODULE,
|
|
.ctr = linear_ctr,
|
|
.dtr = linear_dtr,
|
|
.map = linear_map,
|
|
.status = linear_status,
|
|
.ioctl = linear_ioctl,
|
|
};
|
|
|
|
int __init dm_linear_init(void)
|
|
{
|
|
int r = dm_register_target(&linear_target);
|
|
|
|
if (r < 0)
|
|
DMERR("register failed %d", r);
|
|
|
|
return r;
|
|
}
|
|
|
|
void dm_linear_exit(void)
|
|
{
|
|
int r = dm_unregister_target(&linear_target);
|
|
|
|
if (r < 0)
|
|
DMERR("unregister failed %d", r);
|
|
}
|