// SPDX-License-Identifier: GPL-2.0
#include <linux/capability.h>
#include <linux/compat.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>
#include "blk.h"

static int blkpg_do_ioctl(struct block_device *bdev,
                          struct blkpg_partition __user *upart, int op)
{
        struct blkpg_partition p;
        long long start, length;

        if (!capable(CAP_SYS_ADMIN))
                return -EACCES;
        if (copy_from_user(&p, upart, sizeof(struct blkpg_partition)))
                return -EFAULT;
        if (bdev_is_partition(bdev))
                return -EINVAL;

        if (p.pno <= 0)
                return -EINVAL;

        if (op == BLKPG_DEL_PARTITION)
                return bdev_del_partition(bdev, p.pno);

        start = p.start >> SECTOR_SHIFT;
        length = p.length >> SECTOR_SHIFT;

        /* check for fit in a hd_struct */
        if (sizeof(sector_t) < sizeof(long long)) {
                long pstart = start, plength = length;

                if (pstart != start || plength != length || pstart < 0 ||
                    plength < 0 || p.pno > 65535)
                        return -EINVAL;
        }

        switch (op) {
        case BLKPG_ADD_PARTITION:
                /* check if partition is aligned to blocksize */
                if (p.start & (bdev_logical_block_size(bdev) - 1))
                        return -EINVAL;
                return bdev_add_partition(bdev, p.pno, start, length);
        case BLKPG_RESIZE_PARTITION:
                return bdev_resize_partition(bdev, p.pno, start, length);
        default:
                return -EINVAL;
        }
}

static int blkpg_ioctl(struct block_device *bdev,
                       struct blkpg_ioctl_arg __user *arg)
{
        struct blkpg_partition __user *udata;
        int op;

        if (get_user(op, &arg->op) || get_user(udata, &arg->data))
                return -EFAULT;

        return blkpg_do_ioctl(bdev, udata, op);
}

#ifdef CONFIG_COMPAT
struct compat_blkpg_ioctl_arg {
        compat_int_t op;
        compat_int_t flags;
        compat_int_t datalen;
        compat_caddr_t data;
};

static int compat_blkpg_ioctl(struct block_device *bdev,
                              struct compat_blkpg_ioctl_arg __user *arg)
{
        compat_caddr_t udata;
        int op;

        if (get_user(op, &arg->op) || get_user(udata, &arg->data))
                return -EFAULT;

        return blkpg_do_ioctl(bdev, compat_ptr(udata), op);
}
#endif

static int blkdev_reread_part(struct block_device *bdev)
{
        int ret;

        if (!disk_part_scan_enabled(bdev->bd_disk) || bdev_is_partition(bdev))
                return -EINVAL;
        if (!capable(CAP_SYS_ADMIN))
                return -EACCES;

        mutex_lock(&bdev->bd_mutex);
        ret = bdev_disk_changed(bdev, false);
        mutex_unlock(&bdev->bd_mutex);

        return ret;
}

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);
        int err;

        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;

        err = truncate_bdev_range(bdev, mode, start, start + len - 1);
        if (err)
                return err;

        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];
        uint64_t start, end, len;
        int err;

        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 */
        err = truncate_bdev_range(bdev, mode, start, end);
        if (err)
                return err;

        return blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL,
                        BLKDEV_ZERO_NOUNMAP);
}

static int put_ushort(unsigned short __user *argp, unsigned short val)
{
        return put_user(val, argp);
}

static int put_int(int __user *argp, int val)
{
        return put_user(val, argp);
}

static int put_uint(unsigned int __user *argp, unsigned int val)
{
        return put_user(val, argp);
}

static int put_long(long __user *argp, long val)
{
        return put_user(val, argp);
}

static int put_ulong(unsigned long __user *argp, unsigned long val)
{
        return put_user(val, argp);
}

static int put_u64(u64 __user *argp, u64 val)
{
        return put_user(val, argp);
}

#ifdef CONFIG_COMPAT
static int compat_put_long(compat_long_t __user *argp, long val)
{
        return put_user(val, argp);
}

static int compat_put_ulong(compat_ulong_t __user *argp, compat_ulong_t val)
{
        return put_user(val, argp);
}
#endif

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);

#ifdef CONFIG_COMPAT
/*
 * This is the equivalent of compat_ptr_ioctl(), to be used by block
 * drivers that implement only commands that are completely compatible
 * between 32-bit and 64-bit user space
 */
int blkdev_compat_ptr_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,
                                         (unsigned long)compat_ptr(arg));

        return -ENOIOCTLCMD;
}
EXPORT_SYMBOL(blkdev_compat_ptr_ioctl);
#endif

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(&reg, 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;
}

#ifdef CONFIG_COMPAT
struct compat_hd_geometry {
        unsigned char heads;
        unsigned char sectors;
        unsigned short cylinders;
        u32 start;
};

static int compat_hdio_getgeo(struct block_device *bdev,
                              struct compat_hd_geometry __user *ugeo)
{
        struct gendisk *disk = bdev->bd_disk;
        struct hd_geometry geo;
        int ret;

        if (!ugeo)
                return -EINVAL;
        if (!disk->fops->getgeo)
                return -ENOTTY;

        memset(&geo, 0, sizeof(geo));
        /*
         * We need to set the startsect first, the driver may
         * want to override it.
         */
        geo.start = get_start_sect(bdev);
        ret = disk->fops->getgeo(bdev, &geo);
        if (ret)
                return ret;

        ret = copy_to_user(ugeo, &geo, 4);
        ret |= put_user(geo.start, &ugeo->start);
        if (ret)
                ret = -EFAULT;

        return ret;
}
#endif

/* 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)
                return set_blocksize(bdev, n);

        if (IS_ERR(blkdev_get_by_dev(bdev->bd_dev, mode | FMODE_EXCL, &bdev)))
                return -EBUSY;
        ret = set_blocksize(bdev, n);
        blkdev_put(bdev, mode | FMODE_EXCL);

        return ret;
}

/*
 * Common commands that are handled the same way on native and compat
 * user space. Note the separate arg/argp parameters that are needed
 * to deal with the compat_ptr() conversion.
 */
static int blkdev_common_ioctl(struct block_device *bdev, fmode_t mode,
                                unsigned cmd, unsigned long arg, void __user *argp)
{
        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:
        case BLKOPENZONE:
        case BLKCLOSEZONE:
        case BLKFINISHZONE:
                return blkdev_zone_mgmt_ioctl(bdev, mode, cmd, arg);
        case BLKGETZONESZ:
                return put_uint(argp, bdev_zone_sectors(bdev));
        case BLKGETNRZONES:
                return put_uint(argp, blkdev_nr_zones(bdev->bd_disk));
        case BLKROGET:
                return put_int(argp, bdev_read_only(bdev) != 0);
        case BLKSSZGET: /* get block device logical block size */
                return put_int(argp, bdev_logical_block_size(bdev));
        case BLKPBSZGET: /* get block device physical block size */
                return put_uint(argp, bdev_physical_block_size(bdev));
        case BLKIOMIN:
                return put_uint(argp, bdev_io_min(bdev));
        case BLKIOOPT:
                return put_uint(argp, bdev_io_opt(bdev));
        case BLKALIGNOFF:
                return put_int(argp, bdev_alignment_offset(bdev));
        case BLKDISCARDZEROES:
                return put_uint(argp, 0);
        case BLKSECTGET:
                max_sectors = min_t(unsigned int, USHRT_MAX,
                                    queue_max_sectors(bdev_get_queue(bdev)));
                return put_ushort(argp, max_sectors);
        case BLKROTATIONAL:
                return put_ushort(argp, !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 BLKRRPART:
                return blkdev_reread_part(bdev);
        case BLKTRACESTART:
        case BLKTRACESTOP:
        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 -ENOIOCTLCMD;
        }
}

/*
 * Always keep this in sync with compat_blkdev_ioctl()
 * to handle all incompatible commands in both functions.
 *
 * New commands must be compatible and go into blkdev_common_ioctl
 */
int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
                        unsigned long arg)
{
        int ret;
        loff_t size;
        void __user *argp = (void __user *)arg;

        switch (cmd) {
        /* These need separate implementations for the data structure */
        case HDIO_GETGEO:
                return blkdev_getgeo(bdev, argp);
        case BLKPG:
                return blkpg_ioctl(bdev, argp);

        /* Compat mode returns 32-bit data instead of 'long' */
        case BLKRAGET:
        case BLKFRAGET:
                if (!argp)
                        return -EINVAL;
                return put_long(argp, (bdev->bd_bdi->ra_pages*PAGE_SIZE) / 512);
        case BLKGETSIZE:
                size = i_size_read(bdev->bd_inode);
                if ((size >> 9) > ~0UL)
                        return -EFBIG;
                return put_ulong(argp, size >> 9);

        /* The data is compatible, but the command number is different */
        case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */
                return put_int(argp, block_size(bdev));
        case BLKBSZSET:
                return blkdev_bszset(bdev, mode, argp);
        case BLKGETSIZE64:
                return put_u64(argp, i_size_read(bdev->bd_inode));

        /* Incompatible alignment on i386 */
        case BLKTRACESETUP:
                return blk_trace_ioctl(bdev, cmd, argp);
        default:
                break;
        }

        ret = blkdev_common_ioctl(bdev, mode, cmd, arg, argp);
        if (ret == -ENOIOCTLCMD)
                return __blkdev_driver_ioctl(bdev, mode, cmd, arg);

        return ret;
}
EXPORT_SYMBOL_GPL(blkdev_ioctl); /* for /dev/raw */

#ifdef CONFIG_COMPAT

#define BLKBSZGET_32            _IOR(0x12, 112, int)
#define BLKBSZSET_32            _IOW(0x12, 113, int)
#define BLKGETSIZE64_32         _IOR(0x12, 114, int)

/* Most of the generic ioctls are handled in the normal fallback path.
   This assumes the blkdev's low level compat_ioctl always returns
   ENOIOCTLCMD for unknown ioctls. */
long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
{
        int ret;
        void __user *argp = compat_ptr(arg);
        struct inode *inode = file->f_mapping->host;
        struct block_device *bdev = inode->i_bdev;
        struct gendisk *disk = bdev->bd_disk;
        fmode_t mode = file->f_mode;
        loff_t size;

        /*
         * O_NDELAY can be altered using fcntl(.., F_SETFL, ..), so we have
         * to updated it before every ioctl.
         */
        if (file->f_flags & O_NDELAY)
                mode |= FMODE_NDELAY;
        else
                mode &= ~FMODE_NDELAY;

        switch (cmd) {
        /* These need separate implementations for the data structure */
        case HDIO_GETGEO:
                return compat_hdio_getgeo(bdev, argp);
        case BLKPG:
                return compat_blkpg_ioctl(bdev, argp);

        /* Compat mode returns 32-bit data instead of 'long' */
        case BLKRAGET:
        case BLKFRAGET:
                if (!argp)
                        return -EINVAL;
                return compat_put_long(argp,
                               (bdev->bd_bdi->ra_pages * PAGE_SIZE) / 512);
        case BLKGETSIZE:
                size = i_size_read(bdev->bd_inode);
                if ((size >> 9) > ~0UL)
                        return -EFBIG;
                return compat_put_ulong(argp, size >> 9);

        /* The data is compatible, but the command number is different */
        case BLKBSZGET_32: /* get the logical block size (cf. BLKSSZGET) */
                return put_int(argp, bdev_logical_block_size(bdev));
        case BLKBSZSET_32:
                return blkdev_bszset(bdev, mode, argp);
        case BLKGETSIZE64_32:
                return put_u64(argp, i_size_read(bdev->bd_inode));

        /* Incompatible alignment on i386 */
        case BLKTRACESETUP32:
                return blk_trace_ioctl(bdev, cmd, argp);
        default:
                break;
        }

        ret = blkdev_common_ioctl(bdev, mode, cmd, arg, argp);
        if (ret == -ENOIOCTLCMD && disk->fops->compat_ioctl)
                ret = disk->fops->compat_ioctl(bdev, mode, cmd, arg);

        return ret;
}
#endif