// SPDX-License-Identifier: GPL-2.0
/*
 * ide-floppy IOCTLs handling.
 */

#include <linux/kernel.h>
#include <linux/ide.h>
#include <linux/cdrom.h>
#include <linux/mutex.h>

#include <asm/unaligned.h>

#include <scsi/scsi_ioctl.h>

#include "ide-floppy.h"

/*
 * Obtain the list of formattable capacities.
 * Very similar to ide_floppy_get_capacity, except that we push the capacity
 * descriptors to userland, instead of our own structures.
 *
 * Userland gives us the following structure:
 *
 * struct idefloppy_format_capacities {
 *      int nformats;
 *      struct {
 *              int nblocks;
 *              int blocksize;
 *      } formats[];
 * };
 *
 * userland initializes nformats to the number of allocated formats[] records.
 * On exit we set nformats to the number of records we've actually initialized.
 */

static DEFINE_MUTEX(ide_floppy_ioctl_mutex);
static int ide_floppy_get_format_capacities(ide_drive_t *drive,
                                            struct ide_atapi_pc *pc,
                                            int __user *arg)
{
        struct ide_disk_obj *floppy = drive->driver_data;
        int i, blocks, length, u_array_size, u_index;
        int __user *argp;
        u8 pc_buf[256], header_len, desc_cnt;

        if (get_user(u_array_size, arg))
                return -EFAULT;

        if (u_array_size <= 0)
                return -EINVAL;

        ide_floppy_create_read_capacity_cmd(pc);

        if (ide_queue_pc_tail(drive, floppy->disk, pc, pc_buf, pc->req_xfer)) {
                printk(KERN_ERR "ide-floppy: Can't get floppy parameters\n");
                return -EIO;
        }

        header_len = pc_buf[3];
        desc_cnt = header_len / 8; /* capacity descriptor of 8 bytes */

        u_index = 0;
        argp = arg + 1;

        /*
         * We always skip the first capacity descriptor.  That's the current
         * capacity.  We are interested in the remaining descriptors, the
         * formattable capacities.
         */
        for (i = 1; i < desc_cnt; i++) {
                unsigned int desc_start = 4 + i*8;

                if (u_index >= u_array_size)
                        break;  /* User-supplied buffer too small */

                blocks = be32_to_cpup((__be32 *)&pc_buf[desc_start]);
                length = be16_to_cpup((__be16 *)&pc_buf[desc_start + 6]);

                if (put_user(blocks, argp))
                        return -EFAULT;

                ++argp;

                if (put_user(length, argp))
                        return -EFAULT;

                ++argp;

                ++u_index;
        }

        if (put_user(u_index, arg))
                return -EFAULT;

        return 0;
}

static void ide_floppy_create_format_unit_cmd(struct ide_atapi_pc *pc,
                                              u8 *buf, int b, int l,
                                              int flags)
{
        ide_init_pc(pc);
        pc->c[0] = GPCMD_FORMAT_UNIT;
        pc->c[1] = 0x17;

        memset(buf, 0, 12);
        buf[1] = 0xA2;
        /* Default format list header, u8 1: FOV/DCRT/IMM bits set */

        if (flags & 1)                          /* Verify bit on... */
                buf[1] ^= 0x20;                 /* ... turn off DCRT bit */
        buf[3] = 8;

        put_unaligned(cpu_to_be32(b), (unsigned int *)(&buf[4]));
        put_unaligned(cpu_to_be32(l), (unsigned int *)(&buf[8]));
        pc->req_xfer = 12;
        pc->flags |= PC_FLAG_WRITING;
}

static int ide_floppy_get_sfrp_bit(ide_drive_t *drive, struct ide_atapi_pc *pc)
{
        struct ide_disk_obj *floppy = drive->driver_data;
        u8 buf[20];

        drive->atapi_flags &= ~IDE_AFLAG_SRFP;

        ide_floppy_create_mode_sense_cmd(pc, IDEFLOPPY_CAPABILITIES_PAGE);
        pc->flags |= PC_FLAG_SUPPRESS_ERROR;

        if (ide_queue_pc_tail(drive, floppy->disk, pc, buf, pc->req_xfer))
                return 1;

        if (buf[8 + 2] & 0x40)
                drive->atapi_flags |= IDE_AFLAG_SRFP;

        return 0;
}

static int ide_floppy_format_unit(ide_drive_t *drive, struct ide_atapi_pc *pc,
                                  int __user *arg)
{
        struct ide_disk_obj *floppy = drive->driver_data;
        u8 buf[12];
        int blocks, length, flags, err = 0;

        if (floppy->openers > 1) {
                /* Don't format if someone is using the disk */
                drive->dev_flags &= ~IDE_DFLAG_FORMAT_IN_PROGRESS;
                return -EBUSY;
        }

        drive->dev_flags |= IDE_DFLAG_FORMAT_IN_PROGRESS;

        /*
         * Send ATAPI_FORMAT_UNIT to the drive.
         *
         * Userland gives us the following structure:
         *
         * struct idefloppy_format_command {
         *        int nblocks;
         *        int blocksize;
         *        int flags;
         *        } ;
         *
         * flags is a bitmask, currently, the only defined flag is:
         *
         *        0x01 - verify media after format.
         */
        if (get_user(blocks, arg) ||
                        get_user(length, arg+1) ||
                        get_user(flags, arg+2)) {
                err = -EFAULT;
                goto out;
        }

        ide_floppy_get_sfrp_bit(drive, pc);
        ide_floppy_create_format_unit_cmd(pc, buf, blocks, length, flags);

        if (ide_queue_pc_tail(drive, floppy->disk, pc, buf, pc->req_xfer))
                err = -EIO;

out:
        if (err)
                drive->dev_flags &= ~IDE_DFLAG_FORMAT_IN_PROGRESS;
        return err;
}

/*
 * Get ATAPI_FORMAT_UNIT progress indication.
 *
 * Userland gives a pointer to an int.  The int is set to a progress
 * indicator 0-65536, with 65536=100%.
 *
 * If the drive does not support format progress indication, we just check
 * the dsc bit, and return either 0 or 65536.
 */

static int ide_floppy_get_format_progress(ide_drive_t *drive,
                                          struct ide_atapi_pc *pc,
                                          int __user *arg)
{
        struct ide_disk_obj *floppy = drive->driver_data;
        u8 sense_buf[18];
        int progress_indication = 0x10000;

        if (drive->atapi_flags & IDE_AFLAG_SRFP) {
                ide_create_request_sense_cmd(drive, pc);
                if (ide_queue_pc_tail(drive, floppy->disk, pc, sense_buf,
                                      pc->req_xfer))
                        return -EIO;

                if (floppy->sense_key == 2 &&
                    floppy->asc == 4 &&
                    floppy->ascq == 4)
                        progress_indication = floppy->progress_indication;

                /* Else assume format_unit has finished, and we're at 0x10000 */
        } else {
                ide_hwif_t *hwif = drive->hwif;
                unsigned long flags;
                u8 stat;

                local_irq_save(flags);
                stat = hwif->tp_ops->read_status(hwif);
                local_irq_restore(flags);

                progress_indication = ((stat & ATA_DSC) == 0) ? 0 : 0x10000;
        }

        if (put_user(progress_indication, arg))
                return -EFAULT;

        return 0;
}

static int ide_floppy_lockdoor(ide_drive_t *drive, struct ide_atapi_pc *pc,
                               unsigned long arg, unsigned int cmd)
{
        struct ide_disk_obj *floppy = drive->driver_data;
        struct gendisk *disk = floppy->disk;
        int prevent = (arg && cmd != CDROMEJECT) ? 1 : 0;

        if (floppy->openers > 1)
                return -EBUSY;

        ide_set_media_lock(drive, disk, prevent);

        if (cmd == CDROMEJECT)
                ide_do_start_stop(drive, disk, 2);

        return 0;
}

static int ide_floppy_format_ioctl(ide_drive_t *drive, struct ide_atapi_pc *pc,
                                   fmode_t mode, unsigned int cmd,
                                   void __user *argp)
{
        switch (cmd) {
        case IDEFLOPPY_IOCTL_FORMAT_SUPPORTED:
                return 0;
        case IDEFLOPPY_IOCTL_FORMAT_GET_CAPACITY:
                return ide_floppy_get_format_capacities(drive, pc, argp);
        case IDEFLOPPY_IOCTL_FORMAT_START:
                if (!(mode & FMODE_WRITE))
                        return -EPERM;
                return ide_floppy_format_unit(drive, pc, (int __user *)argp);
        case IDEFLOPPY_IOCTL_FORMAT_GET_PROGRESS:
                return ide_floppy_get_format_progress(drive, pc, argp);
        default:
                return -ENOTTY;
        }
}

int ide_floppy_ioctl(ide_drive_t *drive, struct block_device *bdev,
                     fmode_t mode, unsigned int cmd, unsigned long arg)
{
        struct ide_atapi_pc pc;
        void __user *argp = (void __user *)arg;
        int err;

        mutex_lock(&ide_floppy_ioctl_mutex);
        if (cmd == CDROMEJECT || cmd == CDROM_LOCKDOOR) {
                err = ide_floppy_lockdoor(drive, &pc, arg, cmd);
                goto out;
        }

        err = ide_floppy_format_ioctl(drive, &pc, mode, cmd, argp);
        if (err != -ENOTTY)
                goto out;

        /*
         * skip SCSI_IOCTL_SEND_COMMAND (deprecated)
         * and CDROM_SEND_PACKET (legacy) ioctls
         */
        if (cmd != CDROM_SEND_PACKET && cmd != SCSI_IOCTL_SEND_COMMAND)
                err = scsi_cmd_blk_ioctl(bdev, mode, cmd, argp);

        if (err == -ENOTTY)
                err = generic_ide_ioctl(drive, bdev, cmd, arg);

out:
        mutex_unlock(&ide_floppy_ioctl_mutex);
        return err;
}