ioctl.c

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/*
 * ioctl.c - NILFS ioctl operations.
 *
 * Copyright (C) 2007, 2008 Nippon Telegraph and Telephone Corporation.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Written by Koji Sato <[email protected]>.
 */

#include <linux/fs.h>
#include <linux/wait.h>
#include <linux/slab.h>
#include <linux/capability.h>   /* capable() */
#include <linux/uaccess.h>  /* copy_from_user(), copy_to_user() */
#include <linux/vmalloc.h>
#include <linux/compat.h>   /* compat_ptr() */
#include <linux/mount.h>    /* mnt_want_write_file(), mnt_drop_write_file() */
#include <linux/buffer_head.h>
#include <linux/nilfs2_fs.h>
#include "nilfs.h"
#include "segment.h"
#include "bmap.h"
#include "cpfile.h"
#include "sufile.h"
#include "dat.h"


static int nilfs_ioctl_wrap_copy(struct the_nilfs *nilfs,
                 struct nilfs_argv *argv, int dir,
                 ssize_t (*dofunc)(struct the_nilfs *,
                           __u64 *, int,
                           void *, size_t, size_t))
{
    void *buf;
    void __user *base = (void __user *)(unsigned long)argv->v_base;
    size_t maxmembs, total, n;
    ssize_t nr;
    int ret, i;
    __u64 pos, ppos;

    if (argv->v_nmembs == 0)
        return 0;

    if (argv->v_size > PAGE_SIZE)
        return -EINVAL;

    buf = (void *)__get_free_pages(GFP_NOFS, 0);
    if (unlikely(!buf))
        return -ENOMEM;
    maxmembs = PAGE_SIZE / argv->v_size;

    ret = 0;
    total = 0;
    pos = argv->v_index;
    for (i = 0; i < argv->v_nmembs; i += n) {
        n = (argv->v_nmembs - i < maxmembs) ?
            argv->v_nmembs - i : maxmembs;
        if ((dir & _IOC_WRITE) &&
            copy_from_user(buf, base + argv->v_size * i,
                   argv->v_size * n)) {
            ret = -EFAULT;
            break;
        }
        ppos = pos;
        nr = dofunc(nilfs, &pos, argv->v_flags, buf, argv->v_size,
                   n);
        if (nr < 0) {
            ret = nr;
            break;
        }
        if ((dir & _IOC_READ) &&
            copy_to_user(base + argv->v_size * i, buf,
                 argv->v_size * nr)) {
            ret = -EFAULT;
            break;
        }
        total += nr;
        if ((size_t)nr < n)
            break;
        if (pos == ppos)
            pos += n;
    }
    argv->v_nmembs = total;

    free_pages((unsigned long)buf, 0);
    return ret;
}

static int nilfs_ioctl_getflags(struct inode *inode, void __user *argp)
{
    unsigned int flags = NILFS_I(inode)->i_flags & FS_FL_USER_VISIBLE;

    return put_user(flags, (int __user *)argp);
}

static int nilfs_ioctl_setflags(struct inode *inode, struct file *filp,
                void __user *argp)
{
    struct nilfs_transaction_info ti;
    unsigned int flags, oldflags;
    int ret;

    if (!inode_owner_or_capable(inode))
        return -EACCES;

    if (get_user(flags, (int __user *)argp))
        return -EFAULT;

    ret = mnt_want_write_file(filp);
    if (ret)
        return ret;

    flags = nilfs_mask_flags(inode->i_mode, flags);

    mutex_lock(&inode->i_mutex);

    oldflags = NILFS_I(inode)->i_flags;

    /*
     * The IMMUTABLE and APPEND_ONLY flags can only be changed by the
     * relevant capability.
     */
    ret = -EPERM;
    if (((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) &&
        !capable(CAP_LINUX_IMMUTABLE))
        goto out;

    ret = nilfs_transaction_begin(inode->i_sb, &ti, 0);
    if (ret)
        goto out;

    NILFS_I(inode)->i_flags = (oldflags & ~FS_FL_USER_MODIFIABLE) |
        (flags & FS_FL_USER_MODIFIABLE);

    nilfs_set_inode_flags(inode);
    inode->i_ctime = CURRENT_TIME;
    if (IS_SYNC(inode))
        nilfs_set_transaction_flag(NILFS_TI_SYNC);

    nilfs_mark_inode_dirty(inode);
    ret = nilfs_transaction_commit(inode->i_sb);
out:
    mutex_unlock(&inode->i_mutex);
    mnt_drop_write_file(filp);
    return ret;
}

static int nilfs_ioctl_getversion(struct inode *inode, void __user *argp)
{
    return put_user(inode->i_generation, (int __user *)argp);
}

static int nilfs_ioctl_change_cpmode(struct inode *inode, struct file *filp,
                     unsigned int cmd, void __user *argp)
{
    struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
    struct nilfs_transaction_info ti;
    struct nilfs_cpmode cpmode;
    int ret;

    if (!capable(CAP_SYS_ADMIN))
        return -EPERM;

    ret = mnt_want_write_file(filp);
    if (ret)
        return ret;

    ret = -EFAULT;
    if (copy_from_user(&cpmode, argp, sizeof(cpmode)))
        goto out;

    mutex_lock(&nilfs->ns_snapshot_mount_mutex);

    nilfs_transaction_begin(inode->i_sb, &ti, 0);
    ret = nilfs_cpfile_change_cpmode(
        nilfs->ns_cpfile, cpmode.cm_cno, cpmode.cm_mode);
    if (unlikely(ret < 0))
        nilfs_transaction_abort(inode->i_sb);
    else
        nilfs_transaction_commit(inode->i_sb); /* never fails */

    mutex_unlock(&nilfs->ns_snapshot_mount_mutex);
out:
    mnt_drop_write_file(filp);
    return ret;
}

static int
nilfs_ioctl_delete_checkpoint(struct inode *inode, struct file *filp,
                  unsigned int cmd, void __user *argp)
{
    struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
    struct nilfs_transaction_info ti;
    __u64 cno;
    int ret;

    if (!capable(CAP_SYS_ADMIN))
        return -EPERM;

    ret = mnt_want_write_file(filp);
    if (ret)
        return ret;

    ret = -EFAULT;
    if (copy_from_user(&cno, argp, sizeof(cno)))
        goto out;

    nilfs_transaction_begin(inode->i_sb, &ti, 0);
    ret = nilfs_cpfile_delete_checkpoint(nilfs->ns_cpfile, cno);
    if (unlikely(ret < 0))
        nilfs_transaction_abort(inode->i_sb);
    else
        nilfs_transaction_commit(inode->i_sb); /* never fails */
out:
    mnt_drop_write_file(filp);
    return ret;
}

static ssize_t
nilfs_ioctl_do_get_cpinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
              void *buf, size_t size, size_t nmembs)
{
    int ret;

    down_read(&nilfs->ns_segctor_sem);
    ret = nilfs_cpfile_get_cpinfo(nilfs->ns_cpfile, posp, flags, buf,
                      size, nmembs);
    up_read(&nilfs->ns_segctor_sem);
    return ret;
}

static int nilfs_ioctl_get_cpstat(struct inode *inode, struct file *filp,
                  unsigned int cmd, void __user *argp)
{
    struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
    struct nilfs_cpstat cpstat;
    int ret;

    down_read(&nilfs->ns_segctor_sem);
    ret = nilfs_cpfile_get_stat(nilfs->ns_cpfile, &cpstat);
    up_read(&nilfs->ns_segctor_sem);
    if (ret < 0)
        return ret;

    if (copy_to_user(argp, &cpstat, sizeof(cpstat)))
        ret = -EFAULT;
    return ret;
}

static ssize_t
nilfs_ioctl_do_get_suinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
              void *buf, size_t size, size_t nmembs)
{
    int ret;

    down_read(&nilfs->ns_segctor_sem);
    ret = nilfs_sufile_get_suinfo(nilfs->ns_sufile, *posp, buf, size,
                      nmembs);
    up_read(&nilfs->ns_segctor_sem);
    return ret;
}

static int nilfs_ioctl_get_sustat(struct inode *inode, struct file *filp,
                  unsigned int cmd, void __user *argp)
{
    struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
    struct nilfs_sustat sustat;
    int ret;

    down_read(&nilfs->ns_segctor_sem);
    ret = nilfs_sufile_get_stat(nilfs->ns_sufile, &sustat);
    up_read(&nilfs->ns_segctor_sem);
    if (ret < 0)
        return ret;

    if (copy_to_user(argp, &sustat, sizeof(sustat)))
        ret = -EFAULT;
    return ret;
}

static ssize_t
nilfs_ioctl_do_get_vinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
             void *buf, size_t size, size_t nmembs)
{
    int ret;

    down_read(&nilfs->ns_segctor_sem);
    ret = nilfs_dat_get_vinfo(nilfs->ns_dat, buf, size, nmembs);
    up_read(&nilfs->ns_segctor_sem);
    return ret;
}

static ssize_t
nilfs_ioctl_do_get_bdescs(struct the_nilfs *nilfs, __u64 *posp, int flags,
              void *buf, size_t size, size_t nmembs)
{
    struct nilfs_bmap *bmap = NILFS_I(nilfs->ns_dat)->i_bmap;
    struct nilfs_bdesc *bdescs = buf;
    int ret, i;

    down_read(&nilfs->ns_segctor_sem);
    for (i = 0; i < nmembs; i++) {
        ret = nilfs_bmap_lookup_at_level(bmap,
                         bdescs[i].bd_offset,
                         bdescs[i].bd_level + 1,
                         &bdescs[i].bd_blocknr);
        if (ret < 0) {
            if (ret != -ENOENT) {
                up_read(&nilfs->ns_segctor_sem);
                return ret;
            }
            bdescs[i].bd_blocknr = 0;
        }
    }
    up_read(&nilfs->ns_segctor_sem);
    return nmembs;
}

static int nilfs_ioctl_get_bdescs(struct inode *inode, struct file *filp,
                  unsigned int cmd, void __user *argp)
{
    struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
    struct nilfs_argv argv;
    int ret;

    if (copy_from_user(&argv, argp, sizeof(argv)))
        return -EFAULT;

    if (argv.v_size != sizeof(struct nilfs_bdesc))
        return -EINVAL;

    ret = nilfs_ioctl_wrap_copy(nilfs, &argv, _IOC_DIR(cmd),
                    nilfs_ioctl_do_get_bdescs);
    if (ret < 0)
        return ret;

    if (copy_to_user(argp, &argv, sizeof(argv)))
        ret = -EFAULT;
    return ret;
}

static int nilfs_ioctl_move_inode_block(struct inode *inode,
                    struct nilfs_vdesc *vdesc,
                    struct list_head *buffers)
{
    struct buffer_head *bh;
    int ret;

    if (vdesc->vd_flags == 0)
        ret = nilfs_gccache_submit_read_data(
            inode, vdesc->vd_offset, vdesc->vd_blocknr,
            vdesc->vd_vblocknr, &bh);
    else
        ret = nilfs_gccache_submit_read_node(
            inode, vdesc->vd_blocknr, vdesc->vd_vblocknr, &bh);

    if (unlikely(ret < 0)) {
        if (ret == -ENOENT)
            printk(KERN_CRIT
                   "%s: invalid virtual block address (%s): "
                   "ino=%llu, cno=%llu, offset=%llu, "
                   "blocknr=%llu, vblocknr=%llu\n",
                   __func__, vdesc->vd_flags ? "node" : "data",
                   (unsigned long long)vdesc->vd_ino,
                   (unsigned long long)vdesc->vd_cno,
                   (unsigned long long)vdesc->vd_offset,
                   (unsigned long long)vdesc->vd_blocknr,
                   (unsigned long long)vdesc->vd_vblocknr);
        return ret;
    }
    if (unlikely(!list_empty(&bh->b_assoc_buffers))) {
        printk(KERN_CRIT "%s: conflicting %s buffer: ino=%llu, "
               "cno=%llu, offset=%llu, blocknr=%llu, vblocknr=%llu\n",
               __func__, vdesc->vd_flags ? "node" : "data",
               (unsigned long long)vdesc->vd_ino,
               (unsigned long long)vdesc->vd_cno,
               (unsigned long long)vdesc->vd_offset,
               (unsigned long long)vdesc->vd_blocknr,
               (unsigned long long)vdesc->vd_vblocknr);
        brelse(bh);
        return -EEXIST;
    }
    list_add_tail(&bh->b_assoc_buffers, buffers);
    return 0;
}

static int nilfs_ioctl_move_blocks(struct super_block *sb,
                   struct nilfs_argv *argv, void *buf)
{
    size_t nmembs = argv->v_nmembs;
    struct the_nilfs *nilfs = sb->s_fs_info;
    struct inode *inode;
    struct nilfs_vdesc *vdesc;
    struct buffer_head *bh, *n;
    LIST_HEAD(buffers);
    ino_t ino;
    __u64 cno;
    int i, ret;

    for (i = 0, vdesc = buf; i < nmembs; ) {
        ino = vdesc->vd_ino;
        cno = vdesc->vd_cno;
        inode = nilfs_iget_for_gc(sb, ino, cno);
        if (IS_ERR(inode)) {
            ret = PTR_ERR(inode);
            goto failed;
        }
        if (list_empty(&NILFS_I(inode)->i_dirty)) {
            /*
             * Add the inode to GC inode list. Garbage Collection
             * is serialized and no two processes manipulate the
             * list simultaneously.
             */
            igrab(inode);
            list_add(&NILFS_I(inode)->i_dirty,
                 &nilfs->ns_gc_inodes);
        }

        do {
            ret = nilfs_ioctl_move_inode_block(inode, vdesc,
                               &buffers);
            if (unlikely(ret < 0)) {
                iput(inode);
                goto failed;
            }
            vdesc++;
        } while (++i < nmembs &&
             vdesc->vd_ino == ino && vdesc->vd_cno == cno);

        iput(inode); /* The inode still remains in GC inode list */
    }

    list_for_each_entry_safe(bh, n, &buffers, b_assoc_buffers) {
        ret = nilfs_gccache_wait_and_mark_dirty(bh);
        if (unlikely(ret < 0)) {
            WARN_ON(ret == -EEXIST);
            goto failed;
        }
        list_del_init(&bh->b_assoc_buffers);
        brelse(bh);
    }
    return nmembs;

 failed:
    list_for_each_entry_safe(bh, n, &buffers, b_assoc_buffers) {
        list_del_init(&bh->b_assoc_buffers);
        brelse(bh);
    }
    return ret;
}

static int nilfs_ioctl_delete_checkpoints(struct the_nilfs *nilfs,
                      struct nilfs_argv *argv, void *buf)
{
    size_t nmembs = argv->v_nmembs;
    struct inode *cpfile = nilfs->ns_cpfile;
    struct nilfs_period *periods = buf;
    int ret, i;

    for (i = 0; i < nmembs; i++) {
        ret = nilfs_cpfile_delete_checkpoints(
            cpfile, periods[i].p_start, periods[i].p_end);
        if (ret < 0)
            return ret;
    }
    return nmembs;
}

static int nilfs_ioctl_free_vblocknrs(struct the_nilfs *nilfs,
                      struct nilfs_argv *argv, void *buf)
{
    size_t nmembs = argv->v_nmembs;
    int ret;

    ret = nilfs_dat_freev(nilfs->ns_dat, buf, nmembs);

    return (ret < 0) ? ret : nmembs;
}

static int nilfs_ioctl_mark_blocks_dirty(struct the_nilfs *nilfs,
                     struct nilfs_argv *argv, void *buf)
{
    size_t nmembs = argv->v_nmembs;
    struct nilfs_bmap *bmap = NILFS_I(nilfs->ns_dat)->i_bmap;
    struct nilfs_bdesc *bdescs = buf;
    int ret, i;

    for (i = 0; i < nmembs; i++) {
        /* XXX: use macro or inline func to check liveness */
        ret = nilfs_bmap_lookup_at_level(bmap,
                         bdescs[i].bd_offset,
                         bdescs[i].bd_level + 1,
                         &bdescs[i].bd_blocknr);
        if (ret < 0) {
            if (ret != -ENOENT)
                return ret;
            bdescs[i].bd_blocknr = 0;
        }
        if (bdescs[i].bd_blocknr != bdescs[i].bd_oblocknr)
            /* skip dead block */
            continue;
        if (bdescs[i].bd_level == 0) {
            ret = nilfs_mdt_mark_block_dirty(nilfs->ns_dat,
                             bdescs[i].bd_offset);
            if (ret < 0) {
                WARN_ON(ret == -ENOENT);
                return ret;
            }
        } else {
            ret = nilfs_bmap_mark(bmap, bdescs[i].bd_offset,
                          bdescs[i].bd_level);
            if (ret < 0) {
                WARN_ON(ret == -ENOENT);
                return ret;
            }
        }
    }
    return nmembs;
}

int nilfs_ioctl_prepare_clean_segments(struct the_nilfs *nilfs,
                       struct nilfs_argv *argv, void **kbufs)
{
    const char *msg;
    int ret;

    ret = nilfs_ioctl_delete_checkpoints(nilfs, &argv[1], kbufs[1]);
    if (ret < 0) {
        /*
         * can safely abort because checkpoints can be removed
         * independently.
         */
        msg = "cannot delete checkpoints";
        goto failed;
    }
    ret = nilfs_ioctl_free_vblocknrs(nilfs, &argv[2], kbufs[2]);
    if (ret < 0) {
        /*
         * can safely abort because DAT file is updated atomically
         * using a copy-on-write technique.
         */
        msg = "cannot delete virtual blocks from DAT file";
        goto failed;
    }
    ret = nilfs_ioctl_mark_blocks_dirty(nilfs, &argv[3], kbufs[3]);
    if (ret < 0) {
        /*
         * can safely abort because the operation is nondestructive.
         */
        msg = "cannot mark copying blocks dirty";
        goto failed;
    }
    return 0;

 failed:
    printk(KERN_ERR "NILFS: GC failed during preparation: %s: err=%d\n",
           msg, ret);
    return ret;
}

static int nilfs_ioctl_clean_segments(struct inode *inode, struct file *filp,
                      unsigned int cmd, void __user *argp)
{
    struct nilfs_argv argv[5];
    static const size_t argsz[5] = {
        sizeof(struct nilfs_vdesc),
        sizeof(struct nilfs_period),
        sizeof(__u64),
        sizeof(struct nilfs_bdesc),
        sizeof(__u64),
    };
    void __user *base;
    void *kbufs[5];
    struct the_nilfs *nilfs;
    size_t len, nsegs;
    int n, ret;

    if (!capable(CAP_SYS_ADMIN))
        return -EPERM;

    ret = mnt_want_write_file(filp);
    if (ret)
        return ret;

    ret = -EFAULT;
    if (copy_from_user(argv, argp, sizeof(argv)))
        goto out;

    ret = -EINVAL;
    nsegs = argv[4].v_nmembs;
    if (argv[4].v_size != argsz[4])
        goto out;
    if (nsegs > UINT_MAX / sizeof(__u64))
        goto out;

    /*
     * argv[4] points to segment numbers this ioctl cleans.  We
     * use kmalloc() for its buffer because memory used for the
     * segment numbers is enough small.
     */
    kbufs[4] = memdup_user((void __user *)(unsigned long)argv[4].v_base,
                   nsegs * sizeof(__u64));
    if (IS_ERR(kbufs[4])) {
        ret = PTR_ERR(kbufs[4]);
        goto out;
    }
    nilfs = inode->i_sb->s_fs_info;

    for (n = 0; n < 4; n++) {
        ret = -EINVAL;
        if (argv[n].v_size != argsz[n])
            goto out_free;

        if (argv[n].v_nmembs > nsegs * nilfs->ns_blocks_per_segment)
            goto out_free;

        if (argv[n].v_nmembs >= UINT_MAX / argv[n].v_size)
            goto out_free;

        len = argv[n].v_size * argv[n].v_nmembs;
        base = (void __user *)(unsigned long)argv[n].v_base;
        if (len == 0) {
            kbufs[n] = NULL;
            continue;
        }

        kbufs[n] = vmalloc(len);
        if (!kbufs[n]) {
            ret = -ENOMEM;
            goto out_free;
        }
        if (copy_from_user(kbufs[n], base, len)) {
            ret = -EFAULT;
            vfree(kbufs[n]);
            goto out_free;
        }
    }

    /*
     * nilfs_ioctl_move_blocks() will call nilfs_iget_for_gc(),
     * which will operates an inode list without blocking.
     * To protect the list from concurrent operations,
     * nilfs_ioctl_move_blocks should be atomic operation.
     */
    if (test_and_set_bit(THE_NILFS_GC_RUNNING, &nilfs->ns_flags)) {
        ret = -EBUSY;
        goto out_free;
    }

    ret = nilfs_ioctl_move_blocks(inode->i_sb, &argv[0], kbufs[0]);
    if (ret < 0)
        printk(KERN_ERR "NILFS: GC failed during preparation: "
            "cannot read source blocks: err=%d\n", ret);
    else
        ret = nilfs_clean_segments(inode->i_sb, argv, kbufs);

    nilfs_remove_all_gcinodes(nilfs);
    clear_nilfs_gc_running(nilfs);

out_free:
    while (--n >= 0)
        vfree(kbufs[n]);
    kfree(kbufs[4]);
out:
    mnt_drop_write_file(filp);
    return ret;
}

static int nilfs_ioctl_sync(struct inode *inode, struct file *filp,
                unsigned int cmd, void __user *argp)
{
    __u64 cno;
    int ret;
    struct the_nilfs *nilfs;

    ret = nilfs_construct_segment(inode->i_sb);
    if (ret < 0)
        return ret;

    nilfs = inode->i_sb->s_fs_info;
    if (nilfs_test_opt(nilfs, BARRIER)) {
        ret = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL);
        if (ret == -EIO)
            return ret;
    }

    if (argp != NULL) {
        down_read(&nilfs->ns_segctor_sem);
        cno = nilfs->ns_cno - 1;
        up_read(&nilfs->ns_segctor_sem);
        if (copy_to_user(argp, &cno, sizeof(cno)))
            return -EFAULT;
    }
    return 0;
}

static int nilfs_ioctl_resize(struct inode *inode, struct file *filp,
                  void __user *argp)
{
    __u64 newsize;
    int ret = -EPERM;

    if (!capable(CAP_SYS_ADMIN))
        goto out;

    ret = mnt_want_write_file(filp);
    if (ret)
        goto out;

    ret = -EFAULT;
    if (copy_from_user(&newsize, argp, sizeof(newsize)))
        goto out_drop_write;

    ret = nilfs_resize_fs(inode->i_sb, newsize);

out_drop_write:
    mnt_drop_write_file(filp);
out:
    return ret;
}

static int nilfs_ioctl_set_alloc_range(struct inode *inode, void __user *argp)
{
    struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
    __u64 range[2];
    __u64 minseg, maxseg;
    unsigned long segbytes;
    int ret = -EPERM;

    if (!capable(CAP_SYS_ADMIN))
        goto out;

    ret = -EFAULT;
    if (copy_from_user(range, argp, sizeof(__u64[2])))
        goto out;

    ret = -ERANGE;
    if (range[1] > i_size_read(inode->i_sb->s_bdev->bd_inode))
        goto out;

    segbytes = nilfs->ns_blocks_per_segment * nilfs->ns_blocksize;

    minseg = range[0] + segbytes - 1;
    do_div(minseg, segbytes);
    maxseg = NILFS_SB2_OFFSET_BYTES(range[1]);
    do_div(maxseg, segbytes);
    maxseg--;

    ret = nilfs_sufile_set_alloc_range(nilfs->ns_sufile, minseg, maxseg);
out:
    return ret;
}

static int nilfs_ioctl_get_info(struct inode *inode, struct file *filp,
                unsigned int cmd, void __user *argp,
                size_t membsz,
                ssize_t (*dofunc)(struct the_nilfs *,
                          __u64 *, int,
                          void *, size_t, size_t))

{
    struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
    struct nilfs_argv argv;
    int ret;

    if (copy_from_user(&argv, argp, sizeof(argv)))
        return -EFAULT;

    if (argv.v_size < membsz)
        return -EINVAL;

    ret = nilfs_ioctl_wrap_copy(nilfs, &argv, _IOC_DIR(cmd), dofunc);
    if (ret < 0)
        return ret;

    if (copy_to_user(argp, &argv, sizeof(argv)))
        ret = -EFAULT;
    return ret;
}

long nilfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
    struct inode *inode = filp->f_dentry->d_inode;
    void __user *argp = (void __user *)arg;

    switch (cmd) {
    case FS_IOC_GETFLAGS:
        return nilfs_ioctl_getflags(inode, argp);
    case FS_IOC_SETFLAGS:
        return nilfs_ioctl_setflags(inode, filp, argp);
    case FS_IOC_GETVERSION:
        return nilfs_ioctl_getversion(inode, argp);
    case NILFS_IOCTL_CHANGE_CPMODE:
        return nilfs_ioctl_change_cpmode(inode, filp, cmd, argp);
    case NILFS_IOCTL_DELETE_CHECKPOINT:
        return nilfs_ioctl_delete_checkpoint(inode, filp, cmd, argp);
    case NILFS_IOCTL_GET_CPINFO:
        return nilfs_ioctl_get_info(inode, filp, cmd, argp,
                        sizeof(struct nilfs_cpinfo),
                        nilfs_ioctl_do_get_cpinfo);
    case NILFS_IOCTL_GET_CPSTAT:
        return nilfs_ioctl_get_cpstat(inode, filp, cmd, argp);
    case NILFS_IOCTL_GET_SUINFO:
        return nilfs_ioctl_get_info(inode, filp, cmd, argp,
                        sizeof(struct nilfs_suinfo),
                        nilfs_ioctl_do_get_suinfo);
    case NILFS_IOCTL_GET_SUSTAT:
        return nilfs_ioctl_get_sustat(inode, filp, cmd, argp);
    case NILFS_IOCTL_GET_VINFO:
        return nilfs_ioctl_get_info(inode, filp, cmd, argp,
                        sizeof(struct nilfs_vinfo),
                        nilfs_ioctl_do_get_vinfo);
    case NILFS_IOCTL_GET_BDESCS:
        return nilfs_ioctl_get_bdescs(inode, filp, cmd, argp);
    case NILFS_IOCTL_CLEAN_SEGMENTS:
        return nilfs_ioctl_clean_segments(inode, filp, cmd, argp);
    case NILFS_IOCTL_SYNC:
        return nilfs_ioctl_sync(inode, filp, cmd, argp);
    case NILFS_IOCTL_RESIZE:
        return nilfs_ioctl_resize(inode, filp, argp);
    case NILFS_IOCTL_SET_ALLOC_RANGE:
        return nilfs_ioctl_set_alloc_range(inode, argp);
    default:
        return -ENOTTY;
    }
}

#ifdef CONFIG_COMPAT
long nilfs_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
    switch (cmd) {
    case FS_IOC32_GETFLAGS:
        cmd = FS_IOC_GETFLAGS;
        break;
    case FS_IOC32_SETFLAGS:
        cmd = FS_IOC_SETFLAGS;
        break;
    case FS_IOC32_GETVERSION:
        cmd = FS_IOC_GETVERSION;
        break;
    case NILFS_IOCTL_CHANGE_CPMODE:
    case NILFS_IOCTL_DELETE_CHECKPOINT:
    case NILFS_IOCTL_GET_CPINFO:
    case NILFS_IOCTL_GET_CPSTAT:
    case NILFS_IOCTL_GET_SUINFO:
    case NILFS_IOCTL_GET_SUSTAT:
    case NILFS_IOCTL_GET_VINFO:
    case NILFS_IOCTL_GET_BDESCS:
    case NILFS_IOCTL_CLEAN_SEGMENTS:
    case NILFS_IOCTL_SYNC:
    case NILFS_IOCTL_RESIZE:
    case NILFS_IOCTL_SET_ALLOC_RANGE:
        break;
    default:
        return -ENOIOCTLCMD;
    }
    return nilfs_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
}
#endif