// SPDX-License-Identifier: GPL-2.0
#include <linux/capability.h>
#include <linux/blkdev.h>
#include <linux/export.h>
#include <linux/gfp.h>
#include <linux/blkpg.h>
#include <linux/hdreg.h>
#include <linux/backing-dev.h>
#include <linux/fs.h>
#include <linux/blktrace_api.h>
#include <linux/pr.h>
#include <linux/uaccess.h>
static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg)
{
struct block_device *bdevp;
struct gendisk *disk;
struct hd_struct *part, *lpart;
struct blkpg_ioctl_arg a;
struct blkpg_partition p;
struct disk_part_iter piter;
long long start, length;
int partno;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg)))
return -EFAULT;
if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition)))
return -EFAULT;
disk = bdev->bd_disk;
if (bdev != bdev->bd_contains)
return -EINVAL;
partno = p.pno;
if (partno <= 0)
return -EINVAL;
switch (a.op) {
case BLKPG_ADD_PARTITION:
start = p.start >> 9;
length = p.length >> 9;
/* check for fit in a hd_struct */
if (sizeof(sector_t) == sizeof(long) &&
sizeof(long long) > sizeof(long)) {
long pstart = start, plength = length;
if (pstart != start || plength != length
|| pstart < 0 || plength < 0 || partno > 65535)
return -EINVAL;
}
/* check if partition is aligned to blocksize */
if (p.start & (bdev_logical_block_size(bdev) - 1))
return -EINVAL;
mutex_lock(&bdev->bd_mutex);
/* overlap? */
disk_part_iter_init(&piter, disk,
DISK_PITER_INCL_EMPTY);
while ((part = disk_part_iter_next(&piter))) {
if (!(start + length <= part->start_sect ||
start >= part->start_sect + part->nr_sects)) {
disk_part_iter_exit(&piter);
mutex_unlock(&bdev->bd_mutex);
return -EBUSY;
}
}
disk_part_iter_exit(&piter);
/* all seems OK */
part = add_partition(disk, partno, start, length,
ADDPART_FLAG_NONE, NULL);
mutex_unlock(&bdev->bd_mutex);
return PTR_ERR_OR_ZERO(part);
case BLKPG_DEL_PARTITION:
part = disk_get_part(disk, partno);
if (!part)
return -ENXIO;
bdevp = bdget(part_devt(part));
disk_put_part(part);
if (!bdevp)
return -ENOMEM;
mutex_lock(&bdevp->bd_mutex);
if (bdevp->bd_openers) {
mutex_unlock(&bdevp->bd_mutex);
bdput(bdevp);
return -EBUSY;
}
/* all seems OK */
fsync_bdev(bdevp);
invalidate_bdev(bdevp);
mutex_lock_nested(&bdev->bd_mutex, 1);
delete_partition(disk, partno);
mutex_unlock(&bdev->bd_mutex);
mutex_unlock(&bdevp->bd_mutex);
bdput(bdevp);
return 0;
case BLKPG_RESIZE_PARTITION:
start = p.start >> 9;
/* new length of partition in bytes */
length = p.length >> 9;
/* check for fit in a hd_struct */
if (sizeof(sector_t) == sizeof(long) &&
sizeof(long long) > sizeof(long)) {
long pstart = start, plength = length;
if (pstart != start || plength != length
|| pstart < 0 || plength < 0)
return -EINVAL;
}
part = disk_get_part(disk, partno);
if (!part)
return -ENXIO;
bdevp = bdget(part_devt(part));
if (!bdevp) {
disk_put_part(part);
return -ENOMEM;
}
mutex_lock(&bdevp->bd_mutex);
mutex_lock_nested(&bdev->bd_mutex, 1);
if (start != part->start_sect) {
mutex_unlock(&bdevp->bd_mutex);
mutex_unlock(&bdev->bd_mutex);
bdput(bdevp);
disk_put_part(part);
return -EINVAL;
}
/* overlap? */
disk_part_iter_init(&piter, disk,
DISK_PITER_INCL_EMPTY);
while ((lpart = disk_part_iter_next(&piter))) {
if (lpart->partno != partno &&
!(start + length <= lpart->start_sect ||
start >= lpart->start_sect + lpart->nr_sects)
) {
disk_part_iter_exit(&piter);
mutex_unlock(&bdevp->bd_mutex);
mutex_unlock(&bdev->bd_mutex);
bdput(bdevp);
disk_put_part(part);
return -EBUSY;
}
}
disk_part_iter_exit(&piter);
part_nr_sects_write(part, (sector_t)length);
i_size_write(bdevp->bd_inode, p.length);
mutex_unlock(&bdevp->bd_mutex);
mutex_unlock(&bdev->bd_mutex);
bdput(bdevp);
disk_put_part(part);
return 0;
default:
return -EINVAL;
}
}
/*
* This is an exported API for the block driver, and will not
* acquire bd_mutex. This API should be used in case that
* caller has held bd_mutex already.
*/
int __blkdev_reread_part(struct block_device *bdev)
{
struct gendisk *disk = bdev->bd_disk;
if (!disk_part_scan_enabled(disk) || bdev != bdev->bd_contains)
return -EINVAL;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
lockdep_assert_held(&bdev->bd_mutex);
return rescan_partitions(disk, bdev);
}
EXPORT_SYMBOL(__blkdev_reread_part);
/*
* This is an exported API for the block driver, and will
* try to acquire bd_mutex. If bd_mutex has been held already
* in current context, please call __blkdev_reread_part().
*
* Make sure the held locks in current context aren't required
* in open()/close() handler and I/O path for avoiding ABBA deadlock:
* - bd_mutex is held before calling block driver's open/close
* handler
* - reading partition table may submit I/O to the block device
*/
int blkdev_reread_part(struct block_device *bdev)
{
int res;
mutex_lock(&bdev->bd_mutex);
res = __blkdev_reread_part(bdev);
mutex_unlock(&bdev->bd_mutex);
return res;
}
EXPORT_SYMBOL(blkdev_reread_part);
static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode,
unsigned long arg, unsigned long flags)
{
uint64_t range[2];
uint64_t start, len;
struct request_queue *q = bdev_get_queue(bdev);
struct address_space *mapping = bdev->bd_inode->i_mapping;
if (!(mode & FMODE_WRITE))
return -EBADF;
if (!blk_queue_discard(q))
return -EOPNOTSUPP;
if (copy_from_user(range, (void __user *)arg, sizeof(range)))
return -EFAULT;
start = range[0];
len = range[1];
if (start & 511)
return -EINVAL;
if (len & 511)
return -EINVAL;
if (start + len > i_size_read(bdev->bd_inode))
return -EINVAL;
truncate_inode_pages_range(mapping, start, start + len - 1);
return blkdev_issue_discard(bdev, start >> 9, len >> 9,
GFP_KERNEL, flags);
}
static int blk_ioctl_zeroout(struct block_device *bdev, fmode_t mode,
unsigned long arg)
{
uint64_t range[2];
struct address_space *mapping;
uint64_t start, end, len;
if (!(mode & FMODE_WRITE))
return -EBADF;
if (copy_from_user(range, (void __user *)arg, sizeof(range)))
return -EFAULT;
start = range[0];
len = range[1];
end = start + len - 1;
if (start & 511)
return -EINVAL;
if (len & 511)
return -EINVAL;
if (end >= (uint64_t)i_size_read(bdev->bd_inode))
return -EINVAL;
if (end < start)
return -EINVAL;
/* Invalidate the page cache, including dirty pages */
mapping = bdev->bd_inode->i_mapping;
truncate_inode_pages_range(mapping, start, end);
return blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL,
BLKDEV_ZERO_NOUNMAP);
}
static int put_ushort(unsigned long arg, unsigned short val)
{
return put_user(val, (unsigned short __user *)arg);
}
static int put_int(unsigned long arg, int val)
{
return put_user(val, (int __user *)arg);
}
static int put_uint(unsigned long arg, unsigned int val)
{
return put_user(val, (unsigned int __user *)arg);
}
static int put_long(unsigned long arg, long val)
{
return put_user(val, (long __user *)arg);
}
static int put_ulong(unsigned long arg, unsigned long val)
{
return put_user(val, (unsigned long __user *)arg);
}
static int put_u64(unsigned long arg, u64 val)
{
return put_user(val, (u64 __user *)arg);
}
int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
unsigned cmd, unsigned long arg)
{
struct gendisk *disk = bdev->bd_disk;
if (disk->fops->ioctl)
return disk->fops->ioctl(bdev, mode, cmd, arg);
return -ENOTTY;
}
/*
* For the record: _GPL here is only because somebody decided to slap it
* on the previous export. Sheer idiocy, since it wasn't copyrightable
* at all and could be open-coded without any exports by anybody who cares.
*/
EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl);
static int blkdev_pr_register(struct block_device *bdev,
struct pr_registration __user *arg)
{
const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
struct pr_registration reg;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (!ops || !ops->pr_register)
return -EOPNOTSUPP;
if (copy_from_user(®, arg, sizeof(reg)))
return -EFAULT;
if (reg.flags & ~PR_FL_IGNORE_KEY)
return -EOPNOTSUPP;
return ops->pr_register(bdev, reg.old_key, reg.new_key, reg.flags);
}
static int blkdev_pr_reserve(struct block_device *bdev,
struct pr_reservation __user *arg)
{
const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
struct pr_reservation rsv;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (!ops || !ops->pr_reserve)
return -EOPNOTSUPP;
if (copy_from_user(&rsv, arg, sizeof(rsv)))
return -EFAULT;
if (rsv.flags & ~PR_FL_IGNORE_KEY)
return -EOPNOTSUPP;
return ops->pr_reserve(bdev, rsv.key, rsv.type, rsv.flags);
}
static int blkdev_pr_release(struct block_device *bdev,
struct pr_reservation __user *arg)
{
const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
struct pr_reservation rsv;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (!ops || !ops->pr_release)
return -EOPNOTSUPP;
if (copy_from_user(&rsv, arg, sizeof(rsv)))
return -EFAULT;
if (rsv.flags)
return -EOPNOTSUPP;
return ops->pr_release(bdev, rsv.key, rsv.type);
}
static int blkdev_pr_preempt(struct block_device *bdev,
struct pr_preempt __user *arg, bool abort)
{
const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
struct pr_preempt p;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (!ops || !ops->pr_preempt)
return -EOPNOTSUPP;
if (copy_from_user(&p, arg, sizeof(p)))
return -EFAULT;
if (p.flags)
return -EOPNOTSUPP;
return ops->pr_preempt(bdev, p.old_key, p.new_key, p.type, abort);
}
static int blkdev_pr_clear(struct block_device *bdev,
struct pr_clear __user *arg)
{
const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
struct pr_clear c;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (!ops || !ops->pr_clear)
return -EOPNOTSUPP;
if (copy_from_user(&c, arg, sizeof(c)))
return -EFAULT;
if (c.flags)
return -EOPNOTSUPP;
return ops->pr_clear(bdev, c.key);
}
/*
* Is it an unrecognized ioctl? The correct returns are either
* ENOTTY (final) or ENOIOCTLCMD ("I don't know this one, try a
* fallback"). ENOIOCTLCMD gets turned into ENOTTY by the ioctl
* code before returning.
*
* Confused drivers sometimes return EINVAL, which is wrong. It
* means "I understood the ioctl command, but the parameters to
* it were wrong".
*
* We should aim to just fix the broken drivers, the EINVAL case
* should go away.
*/
static inline int is_unrecognized_ioctl(int ret)
{
return ret == -EINVAL ||
ret == -ENOTTY ||
ret == -ENOIOCTLCMD;
}
static int blkdev_flushbuf(struct block_device *bdev, fmode_t mode,
unsigned cmd, unsigned long arg)
{
int ret;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
if (!is_unrecognized_ioctl(ret))
return ret;
fsync_bdev(bdev);
invalidate_bdev(bdev);
return 0;
}
static int blkdev_roset(struct block_device *bdev, fmode_t mode,
unsigned cmd, unsigned long arg)
{
int ret, n;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
if (!is_unrecognized_ioctl(ret))
return ret;
if (get_user(n, (int __user *)arg))
return -EFAULT;
set_device_ro(bdev, n);
return 0;
}
static int blkdev_getgeo(struct block_device *bdev,
struct hd_geometry __user *argp)
{
struct gendisk *disk = bdev->bd_disk;
struct hd_geometry geo;
int ret;
if (!argp)
return -EINVAL;
if (!disk->fops->getgeo)
return -ENOTTY;
/*
* We need to set the startsect first, the driver may
* want to override it.
*/
memset(&geo, 0, sizeof(geo));
geo.start = get_start_sect(bdev);
ret = disk->fops->getgeo(bdev, &geo);
if (ret)
return ret;
if (copy_to_user(argp, &geo, sizeof(geo)))
return -EFAULT;
return 0;
}
/* set the logical block size */
static int blkdev_bszset(struct block_device *bdev, fmode_t mode,
int __user *argp)
{
int ret, n;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
if (!argp)
return -EINVAL;
if (get_user(n, argp))
return -EFAULT;
if (!(mode & FMODE_EXCL)) {
bdgrab(bdev);
if (blkdev_get(bdev, mode | FMODE_EXCL, &bdev) < 0)
return -EBUSY;
}
ret = set_blocksize(bdev, n);
if (!(mode & FMODE_EXCL))
blkdev_put(bdev, mode | FMODE_EXCL);
return ret;
}
/*
* always keep this in sync with compat_blkdev_ioctl()
*/
int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
unsigned long arg)
{
void __user *argp = (void __user *)arg;
loff_t size;
unsigned int max_sectors;
switch (cmd) {
case BLKFLSBUF:
return blkdev_flushbuf(bdev, mode, cmd, arg);
case BLKROSET:
return blkdev_roset(bdev, mode, cmd, arg);
case BLKDISCARD:
return blk_ioctl_discard(bdev, mode, arg, 0);
case BLKSECDISCARD:
return blk_ioctl_discard(bdev, mode, arg,
BLKDEV_DISCARD_SECURE);
case BLKZEROOUT:
return blk_ioctl_zeroout(bdev, mode, arg);
case BLKREPORTZONE:
return blkdev_report_zones_ioctl(bdev, mode, cmd, arg);
case BLKRESETZONE:
return blkdev_reset_zones_ioctl(bdev, mode, cmd, arg);
case BLKGETZONESZ:
return put_uint(arg, bdev_zone_sectors(bdev));
case BLKGETNRZONES:
return put_uint(arg, blkdev_nr_zones(bdev));
case HDIO_GETGEO:
return blkdev_getgeo(bdev, argp);
case BLKRAGET:
case BLKFRAGET:
if (!arg)
return -EINVAL;
return put_long(arg, (bdev->bd_bdi->ra_pages*PAGE_SIZE) / 512);
case BLKROGET:
return put_int(arg, bdev_read_only(bdev) != 0);
case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */
return put_int(arg, block_size(bdev));
case BLKSSZGET: /* get block device logical block size */
return put_int(arg, bdev_logical_block_size(bdev));
case BLKPBSZGET: /* get block device physical block size */
return put_uint(arg, bdev_physical_block_size(bdev));
case BLKIOMIN:
return put_uint(arg, bdev_io_min(bdev));
case BLKIOOPT:
return put_uint(arg, bdev_io_opt(bdev));
case BLKALIGNOFF:
return put_int(arg, bdev_alignment_offset(bdev));
case BLKDISCARDZEROES:
return put_uint(arg, 0);
case BLKSECTGET:
max_sectors = min_t(unsigned int, USHRT_MAX,
queue_max_sectors(bdev_get_queue(bdev)));
return put_ushort(arg, max_sectors);
case BLKROTATIONAL:
return put_ushort(arg, !blk_queue_nonrot(bdev_get_queue(bdev)));
case BLKRASET:
case BLKFRASET:
if(!capable(CAP_SYS_ADMIN))
return -EACCES;
bdev->bd_bdi->ra_pages = (arg * 512) / PAGE_SIZE;
return 0;
case BLKBSZSET:
return blkdev_bszset(bdev, mode, argp);
case BLKPG:
return blkpg_ioctl(bdev, argp);
case BLKRRPART:
return blkdev_reread_part(bdev);
case BLKGETSIZE:
size = i_size_read(bdev->bd_inode);
if ((size >> 9) > ~0UL)
return -EFBIG;
return put_ulong(arg, size >> 9);
case BLKGETSIZE64:
return put_u64(arg, i_size_read(bdev->bd_inode));
case BLKTRACESTART:
case BLKTRACESTOP:
case BLKTRACESETUP:
case BLKTRACETEARDOWN:
return blk_trace_ioctl(bdev, cmd, argp);
case IOC_PR_REGISTER:
return blkdev_pr_register(bdev, argp);
case IOC_PR_RESERVE:
return blkdev_pr_reserve(bdev, argp);
case IOC_PR_RELEASE:
return blkdev_pr_release(bdev, argp);
case IOC_PR_PREEMPT:
return blkdev_pr_preempt(bdev, argp, false);
case IOC_PR_PREEMPT_ABORT:
return blkdev_pr_preempt(bdev, argp, true);
case IOC_PR_CLEAR:
return blkdev_pr_clear(bdev, argp);
default:
return __blkdev_driver_ioctl(bdev, mode, cmd, arg);
}
}
EXPORT_SYMBOL_GPL(blkdev_ioctl);
