xfs_ioctl.c

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/*
 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * 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.
 *
 * This program is distributed in the hope that it would 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 the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_log.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_alloc.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_ioctl.h"
#include "xfs_rtalloc.h"
#include "xfs_itable.h"
#include "xfs_error.h"
#include "xfs_attr.h"
#include "xfs_bmap.h"
#include "xfs_buf_item.h"
#include "xfs_utils.h"
#include "xfs_dfrag.h"
#include "xfs_fsops.h"
#include "xfs_vnodeops.h"
#include "xfs_discard.h"
#include "xfs_quota.h"
#include "xfs_inode_item.h"
#include "xfs_export.h"
#include "xfs_trace.h"

#include <linux/capability.h>
#include <linux/dcache.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/exportfs.h>

/*
 * xfs_find_handle maps from userspace xfs_fsop_handlereq structure to
 * a file or fs handle.
 *
 * XFS_IOC_PATH_TO_FSHANDLE
 *    returns fs handle for a mount point or path within that mount point
 * XFS_IOC_FD_TO_HANDLE
 *    returns full handle for a FD opened in user space
 * XFS_IOC_PATH_TO_HANDLE
 *    returns full handle for a path
 */
int
xfs_find_handle(
    unsigned int        cmd,
    xfs_fsop_handlereq_t    *hreq)
{
    int         hsize;
    xfs_handle_t        handle;
    struct inode        *inode;
    struct fd       f = {0};
    struct path     path;
    int         error;
    struct xfs_inode    *ip;

    if (cmd == XFS_IOC_FD_TO_HANDLE) {
        f = fdget(hreq->fd);
        if (!f.file)
            return -EBADF;
        inode = f.file->f_path.dentry->d_inode;
    } else {
        error = user_lpath((const char __user *)hreq->path, &path);
        if (error)
            return error;
        inode = path.dentry->d_inode;
    }
    ip = XFS_I(inode);

    /*
     * We can only generate handles for inodes residing on a XFS filesystem,
     * and only for regular files, directories or symbolic links.
     */
    error = -EINVAL;
    if (inode->i_sb->s_magic != XFS_SB_MAGIC)
        goto out_put;

    error = -EBADF;
    if (!S_ISREG(inode->i_mode) &&
        !S_ISDIR(inode->i_mode) &&
        !S_ISLNK(inode->i_mode))
        goto out_put;


    memcpy(&handle.ha_fsid, ip->i_mount->m_fixedfsid, sizeof(xfs_fsid_t));

    if (cmd == XFS_IOC_PATH_TO_FSHANDLE) {
        /*
         * This handle only contains an fsid, zero the rest.
         */
        memset(&handle.ha_fid, 0, sizeof(handle.ha_fid));
        hsize = sizeof(xfs_fsid_t);
    } else {
        int     lock_mode;

        lock_mode = xfs_ilock_map_shared(ip);
        handle.ha_fid.fid_len = sizeof(xfs_fid_t) -
                    sizeof(handle.ha_fid.fid_len);
        handle.ha_fid.fid_pad = 0;
        handle.ha_fid.fid_gen = ip->i_d.di_gen;
        handle.ha_fid.fid_ino = ip->i_ino;
        xfs_iunlock_map_shared(ip, lock_mode);

        hsize = XFS_HSIZE(handle);
    }

    error = -EFAULT;
    if (copy_to_user(hreq->ohandle, &handle, hsize) ||
        copy_to_user(hreq->ohandlen, &hsize, sizeof(__s32)))
        goto out_put;

    error = 0;

 out_put:
    if (cmd == XFS_IOC_FD_TO_HANDLE)
        fdput(f);
    else
        path_put(&path);
    return error;
}

/*
 * No need to do permission checks on the various pathname components
 * as the handle operations are privileged.
 */
STATIC int
xfs_handle_acceptable(
    void            *context,
    struct dentry       *dentry)
{
    return 1;
}

/*
 * Convert userspace handle data into a dentry.
 */
struct dentry *
xfs_handle_to_dentry(
    struct file     *parfilp,
    void __user     *uhandle,
    u32         hlen)
{
    xfs_handle_t        handle;
    struct xfs_fid64    fid;

    /*
     * Only allow handle opens under a directory.
     */
    if (!S_ISDIR(parfilp->f_path.dentry->d_inode->i_mode))
        return ERR_PTR(-ENOTDIR);

    if (hlen != sizeof(xfs_handle_t))
        return ERR_PTR(-EINVAL);
    if (copy_from_user(&handle, uhandle, hlen))
        return ERR_PTR(-EFAULT);
    if (handle.ha_fid.fid_len !=
        sizeof(handle.ha_fid) - sizeof(handle.ha_fid.fid_len))
        return ERR_PTR(-EINVAL);

    memset(&fid, 0, sizeof(struct fid));
    fid.ino = handle.ha_fid.fid_ino;
    fid.gen = handle.ha_fid.fid_gen;

    return exportfs_decode_fh(parfilp->f_path.mnt, (struct fid *)&fid, 3,
            FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG,
            xfs_handle_acceptable, NULL);
}

STATIC struct dentry *
xfs_handlereq_to_dentry(
    struct file     *parfilp,
    xfs_fsop_handlereq_t    *hreq)
{
    return xfs_handle_to_dentry(parfilp, hreq->ihandle, hreq->ihandlen);
}

int
xfs_open_by_handle(
    struct file     *parfilp,
    xfs_fsop_handlereq_t    *hreq)
{
    const struct cred   *cred = current_cred();
    int         error;
    int         fd;
    int         permflag;
    struct file     *filp;
    struct inode        *inode;
    struct dentry       *dentry;
    fmode_t         fmode;
    struct path     path;

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

    dentry = xfs_handlereq_to_dentry(parfilp, hreq);
    if (IS_ERR(dentry))
        return PTR_ERR(dentry);
    inode = dentry->d_inode;

    /* Restrict xfs_open_by_handle to directories & regular files. */
    if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode))) {
        error = -XFS_ERROR(EPERM);
        goto out_dput;
    }

#if BITS_PER_LONG != 32
    hreq->oflags |= O_LARGEFILE;
#endif

    permflag = hreq->oflags;
    fmode = OPEN_FMODE(permflag);
    if ((!(permflag & O_APPEND) || (permflag & O_TRUNC)) &&
        (fmode & FMODE_WRITE) && IS_APPEND(inode)) {
        error = -XFS_ERROR(EPERM);
        goto out_dput;
    }

    if ((fmode & FMODE_WRITE) && IS_IMMUTABLE(inode)) {
        error = -XFS_ERROR(EACCES);
        goto out_dput;
    }

    /* Can't write directories. */
    if (S_ISDIR(inode->i_mode) && (fmode & FMODE_WRITE)) {
        error = -XFS_ERROR(EISDIR);
        goto out_dput;
    }

    fd = get_unused_fd();
    if (fd < 0) {
        error = fd;
        goto out_dput;
    }

    path.mnt = parfilp->f_path.mnt;
    path.dentry = dentry;
    filp = dentry_open(&path, hreq->oflags, cred);
    dput(dentry);
    if (IS_ERR(filp)) {
        put_unused_fd(fd);
        return PTR_ERR(filp);
    }

    if (S_ISREG(inode->i_mode)) {
        filp->f_flags |= O_NOATIME;
        filp->f_mode |= FMODE_NOCMTIME;
    }

    fd_install(fd, filp);
    return fd;

 out_dput:
    dput(dentry);
    return error;
}

/*
 * This is a copy from fs/namei.c:vfs_readlink(), except for removing it's
 * unused first argument.
 */
STATIC int
do_readlink(
    char __user     *buffer,
    int         buflen,
    const char      *link)
{
        int len;

    len = PTR_ERR(link);
    if (IS_ERR(link))
        goto out;

    len = strlen(link);
    if (len > (unsigned) buflen)
        len = buflen;
    if (copy_to_user(buffer, link, len))
        len = -EFAULT;
 out:
    return len;
}


int
xfs_readlink_by_handle(
    struct file     *parfilp,
    xfs_fsop_handlereq_t    *hreq)
{
    struct dentry       *dentry;
    __u32           olen;
    void            *link;
    int         error;

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

    dentry = xfs_handlereq_to_dentry(parfilp, hreq);
    if (IS_ERR(dentry))
        return PTR_ERR(dentry);

    /* Restrict this handle operation to symlinks only. */
    if (!S_ISLNK(dentry->d_inode->i_mode)) {
        error = -XFS_ERROR(EINVAL);
        goto out_dput;
    }

    if (copy_from_user(&olen, hreq->ohandlen, sizeof(__u32))) {
        error = -XFS_ERROR(EFAULT);
        goto out_dput;
    }

    link = kmalloc(MAXPATHLEN+1, GFP_KERNEL);
    if (!link) {
        error = -XFS_ERROR(ENOMEM);
        goto out_dput;
    }

    error = -xfs_readlink(XFS_I(dentry->d_inode), link);
    if (error)
        goto out_kfree;
    error = do_readlink(hreq->ohandle, olen, link);
    if (error)
        goto out_kfree;

 out_kfree:
    kfree(link);
 out_dput:
    dput(dentry);
    return error;
}

STATIC int
xfs_fssetdm_by_handle(
    struct file     *parfilp,
    void            __user *arg)
{
    int         error;
    struct fsdmidata    fsd;
    xfs_fsop_setdm_handlereq_t dmhreq;
    struct dentry       *dentry;

    if (!capable(CAP_MKNOD))
        return -XFS_ERROR(EPERM);
    if (copy_from_user(&dmhreq, arg, sizeof(xfs_fsop_setdm_handlereq_t)))
        return -XFS_ERROR(EFAULT);

    error = mnt_want_write_file(parfilp);
    if (error)
        return error;

    dentry = xfs_handlereq_to_dentry(parfilp, &dmhreq.hreq);
    if (IS_ERR(dentry)) {
        mnt_drop_write_file(parfilp);
        return PTR_ERR(dentry);
    }

    if (IS_IMMUTABLE(dentry->d_inode) || IS_APPEND(dentry->d_inode)) {
        error = -XFS_ERROR(EPERM);
        goto out;
    }

    if (copy_from_user(&fsd, dmhreq.data, sizeof(fsd))) {
        error = -XFS_ERROR(EFAULT);
        goto out;
    }

    error = -xfs_set_dmattrs(XFS_I(dentry->d_inode), fsd.fsd_dmevmask,
                 fsd.fsd_dmstate);

 out:
    mnt_drop_write_file(parfilp);
    dput(dentry);
    return error;
}

STATIC int
xfs_attrlist_by_handle(
    struct file     *parfilp,
    void            __user *arg)
{
    int         error = -ENOMEM;
    attrlist_cursor_kern_t  *cursor;
    xfs_fsop_attrlist_handlereq_t al_hreq;
    struct dentry       *dentry;
    char            *kbuf;

    if (!capable(CAP_SYS_ADMIN))
        return -XFS_ERROR(EPERM);
    if (copy_from_user(&al_hreq, arg, sizeof(xfs_fsop_attrlist_handlereq_t)))
        return -XFS_ERROR(EFAULT);
    if (al_hreq.buflen > XATTR_LIST_MAX)
        return -XFS_ERROR(EINVAL);

    /*
     * Reject flags, only allow namespaces.
     */
    if (al_hreq.flags & ~(ATTR_ROOT | ATTR_SECURE))
        return -XFS_ERROR(EINVAL);

    dentry = xfs_handlereq_to_dentry(parfilp, &al_hreq.hreq);
    if (IS_ERR(dentry))
        return PTR_ERR(dentry);

    kbuf = kzalloc(al_hreq.buflen, GFP_KERNEL);
    if (!kbuf)
        goto out_dput;

    cursor = (attrlist_cursor_kern_t *)&al_hreq.pos;
    error = -xfs_attr_list(XFS_I(dentry->d_inode), kbuf, al_hreq.buflen,
                    al_hreq.flags, cursor);
    if (error)
        goto out_kfree;

    if (copy_to_user(al_hreq.buffer, kbuf, al_hreq.buflen))
        error = -EFAULT;

 out_kfree:
    kfree(kbuf);
 out_dput:
    dput(dentry);
    return error;
}

int
xfs_attrmulti_attr_get(
    struct inode        *inode,
    unsigned char       *name,
    unsigned char       __user *ubuf,
    __uint32_t      *len,
    __uint32_t      flags)
{
    unsigned char       *kbuf;
    int         error = EFAULT;

    if (*len > XATTR_SIZE_MAX)
        return EINVAL;
    kbuf = kmem_zalloc(*len, KM_SLEEP | KM_MAYFAIL);
    if (!kbuf) {
        kbuf = kmem_zalloc_large(*len);
        if (!kbuf)
            return ENOMEM;
    }

    error = xfs_attr_get(XFS_I(inode), name, kbuf, (int *)len, flags);
    if (error)
        goto out_kfree;

    if (copy_to_user(ubuf, kbuf, *len))
        error = EFAULT;

 out_kfree:
    if (is_vmalloc_addr(kbuf))
        kmem_free_large(kbuf);
    else
        kmem_free(kbuf);
    return error;
}

int
xfs_attrmulti_attr_set(
    struct inode        *inode,
    unsigned char       *name,
    const unsigned char __user *ubuf,
    __uint32_t      len,
    __uint32_t      flags)
{
    unsigned char       *kbuf;
    int         error = EFAULT;

    if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
        return EPERM;
    if (len > XATTR_SIZE_MAX)
        return EINVAL;

    kbuf = memdup_user(ubuf, len);
    if (IS_ERR(kbuf))
        return PTR_ERR(kbuf);

    error = xfs_attr_set(XFS_I(inode), name, kbuf, len, flags);

    return error;
}

int
xfs_attrmulti_attr_remove(
    struct inode        *inode,
    unsigned char       *name,
    __uint32_t      flags)
{
    if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
        return EPERM;
    return xfs_attr_remove(XFS_I(inode), name, flags);
}

STATIC int
xfs_attrmulti_by_handle(
    struct file     *parfilp,
    void            __user *arg)
{
    int         error;
    xfs_attr_multiop_t  *ops;
    xfs_fsop_attrmulti_handlereq_t am_hreq;
    struct dentry       *dentry;
    unsigned int        i, size;
    unsigned char       *attr_name;

    if (!capable(CAP_SYS_ADMIN))
        return -XFS_ERROR(EPERM);
    if (copy_from_user(&am_hreq, arg, sizeof(xfs_fsop_attrmulti_handlereq_t)))
        return -XFS_ERROR(EFAULT);

    /* overflow check */
    if (am_hreq.opcount >= INT_MAX / sizeof(xfs_attr_multiop_t))
        return -E2BIG;

    dentry = xfs_handlereq_to_dentry(parfilp, &am_hreq.hreq);
    if (IS_ERR(dentry))
        return PTR_ERR(dentry);

    error = E2BIG;
    size = am_hreq.opcount * sizeof(xfs_attr_multiop_t);
    if (!size || size > 16 * PAGE_SIZE)
        goto out_dput;

    ops = memdup_user(am_hreq.ops, size);
    if (IS_ERR(ops)) {
        error = PTR_ERR(ops);
        goto out_dput;
    }

    attr_name = kmalloc(MAXNAMELEN, GFP_KERNEL);
    if (!attr_name)
        goto out_kfree_ops;

    error = 0;
    for (i = 0; i < am_hreq.opcount; i++) {
        ops[i].am_error = strncpy_from_user((char *)attr_name,
                ops[i].am_attrname, MAXNAMELEN);
        if (ops[i].am_error == 0 || ops[i].am_error == MAXNAMELEN)
            error = -ERANGE;
        if (ops[i].am_error < 0)
            break;

        switch (ops[i].am_opcode) {
        case ATTR_OP_GET:
            ops[i].am_error = xfs_attrmulti_attr_get(
                    dentry->d_inode, attr_name,
                    ops[i].am_attrvalue, &ops[i].am_length,
                    ops[i].am_flags);
            break;
        case ATTR_OP_SET:
            ops[i].am_error = mnt_want_write_file(parfilp);
            if (ops[i].am_error)
                break;
            ops[i].am_error = xfs_attrmulti_attr_set(
                    dentry->d_inode, attr_name,
                    ops[i].am_attrvalue, ops[i].am_length,
                    ops[i].am_flags);
            mnt_drop_write_file(parfilp);
            break;
        case ATTR_OP_REMOVE:
            ops[i].am_error = mnt_want_write_file(parfilp);
            if (ops[i].am_error)
                break;
            ops[i].am_error = xfs_attrmulti_attr_remove(
                    dentry->d_inode, attr_name,
                    ops[i].am_flags);
            mnt_drop_write_file(parfilp);
            break;
        default:
            ops[i].am_error = EINVAL;
        }
    }

    if (copy_to_user(am_hreq.ops, ops, size))
        error = XFS_ERROR(EFAULT);

    kfree(attr_name);
 out_kfree_ops:
    kfree(ops);
 out_dput:
    dput(dentry);
    return -error;
}

int
xfs_ioc_space(
    struct xfs_inode    *ip,
    struct inode        *inode,
    struct file     *filp,
    int         ioflags,
    unsigned int        cmd,
    xfs_flock64_t       *bf)
{
    int         attr_flags = 0;
    int         error;

    /*
     * Only allow the sys admin to reserve space unless
     * unwritten extents are enabled.
     */
    if (!xfs_sb_version_hasextflgbit(&ip->i_mount->m_sb) &&
        !capable(CAP_SYS_ADMIN))
        return -XFS_ERROR(EPERM);

    if (inode->i_flags & (S_IMMUTABLE|S_APPEND))
        return -XFS_ERROR(EPERM);

    if (!(filp->f_mode & FMODE_WRITE))
        return -XFS_ERROR(EBADF);

    if (!S_ISREG(inode->i_mode))
        return -XFS_ERROR(EINVAL);

    if (filp->f_flags & (O_NDELAY|O_NONBLOCK))
        attr_flags |= XFS_ATTR_NONBLOCK;

    if (filp->f_flags & O_DSYNC)
        attr_flags |= XFS_ATTR_SYNC;

    if (ioflags & IO_INVIS)
        attr_flags |= XFS_ATTR_DMI;

    error = mnt_want_write_file(filp);
    if (error)
        return error;
    error = xfs_change_file_space(ip, cmd, bf, filp->f_pos, attr_flags);
    mnt_drop_write_file(filp);
    return -error;
}

STATIC int
xfs_ioc_bulkstat(
    xfs_mount_t     *mp,
    unsigned int        cmd,
    void            __user *arg)
{
    xfs_fsop_bulkreq_t  bulkreq;
    int         count;  /* # of records returned */
    xfs_ino_t       inlast; /* last inode number */
    int         done;
    int         error;

    /* done = 1 if there are more stats to get and if bulkstat */
    /* should be called again (unused here, but used in dmapi) */

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

    if (XFS_FORCED_SHUTDOWN(mp))
        return -XFS_ERROR(EIO);

    if (copy_from_user(&bulkreq, arg, sizeof(xfs_fsop_bulkreq_t)))
        return -XFS_ERROR(EFAULT);

    if (copy_from_user(&inlast, bulkreq.lastip, sizeof(__s64)))
        return -XFS_ERROR(EFAULT);

    if ((count = bulkreq.icount) <= 0)
        return -XFS_ERROR(EINVAL);

    if (bulkreq.ubuffer == NULL)
        return -XFS_ERROR(EINVAL);

    if (cmd == XFS_IOC_FSINUMBERS)
        error = xfs_inumbers(mp, &inlast, &count,
                    bulkreq.ubuffer, xfs_inumbers_fmt);
    else if (cmd == XFS_IOC_FSBULKSTAT_SINGLE)
        error = xfs_bulkstat_single(mp, &inlast,
                        bulkreq.ubuffer, &done);
    else    /* XFS_IOC_FSBULKSTAT */
        error = xfs_bulkstat(mp, &inlast, &count, xfs_bulkstat_one,
                     sizeof(xfs_bstat_t), bulkreq.ubuffer,
                     &done);

    if (error)
        return -error;

    if (bulkreq.ocount != NULL) {
        if (copy_to_user(bulkreq.lastip, &inlast,
                        sizeof(xfs_ino_t)))
            return -XFS_ERROR(EFAULT);

        if (copy_to_user(bulkreq.ocount, &count, sizeof(count)))
            return -XFS_ERROR(EFAULT);
    }

    return 0;
}

STATIC int
xfs_ioc_fsgeometry_v1(
    xfs_mount_t     *mp,
    void            __user *arg)
{
    xfs_fsop_geom_t         fsgeo;
    int         error;

    error = xfs_fs_geometry(mp, &fsgeo, 3);
    if (error)
        return -error;

    /*
     * Caller should have passed an argument of type
     * xfs_fsop_geom_v1_t.  This is a proper subset of the
     * xfs_fsop_geom_t that xfs_fs_geometry() fills in.
     */
    if (copy_to_user(arg, &fsgeo, sizeof(xfs_fsop_geom_v1_t)))
        return -XFS_ERROR(EFAULT);
    return 0;
}

STATIC int
xfs_ioc_fsgeometry(
    xfs_mount_t     *mp,
    void            __user *arg)
{
    xfs_fsop_geom_t     fsgeo;
    int         error;

    error = xfs_fs_geometry(mp, &fsgeo, 4);
    if (error)
        return -error;

    if (copy_to_user(arg, &fsgeo, sizeof(fsgeo)))
        return -XFS_ERROR(EFAULT);
    return 0;
}

/*
 * Linux extended inode flags interface.
 */

STATIC unsigned int
xfs_merge_ioc_xflags(
    unsigned int    flags,
    unsigned int    start)
{
    unsigned int    xflags = start;

    if (flags & FS_IMMUTABLE_FL)
        xflags |= XFS_XFLAG_IMMUTABLE;
    else
        xflags &= ~XFS_XFLAG_IMMUTABLE;
    if (flags & FS_APPEND_FL)
        xflags |= XFS_XFLAG_APPEND;
    else
        xflags &= ~XFS_XFLAG_APPEND;
    if (flags & FS_SYNC_FL)
        xflags |= XFS_XFLAG_SYNC;
    else
        xflags &= ~XFS_XFLAG_SYNC;
    if (flags & FS_NOATIME_FL)
        xflags |= XFS_XFLAG_NOATIME;
    else
        xflags &= ~XFS_XFLAG_NOATIME;
    if (flags & FS_NODUMP_FL)
        xflags |= XFS_XFLAG_NODUMP;
    else
        xflags &= ~XFS_XFLAG_NODUMP;

    return xflags;
}

STATIC unsigned int
xfs_di2lxflags(
    __uint16_t  di_flags)
{
    unsigned int    flags = 0;

    if (di_flags & XFS_DIFLAG_IMMUTABLE)
        flags |= FS_IMMUTABLE_FL;
    if (di_flags & XFS_DIFLAG_APPEND)
        flags |= FS_APPEND_FL;
    if (di_flags & XFS_DIFLAG_SYNC)
        flags |= FS_SYNC_FL;
    if (di_flags & XFS_DIFLAG_NOATIME)
        flags |= FS_NOATIME_FL;
    if (di_flags & XFS_DIFLAG_NODUMP)
        flags |= FS_NODUMP_FL;
    return flags;
}

STATIC int
xfs_ioc_fsgetxattr(
    xfs_inode_t     *ip,
    int         attr,
    void            __user *arg)
{
    struct fsxattr      fa;

    memset(&fa, 0, sizeof(struct fsxattr));

    xfs_ilock(ip, XFS_ILOCK_SHARED);
    fa.fsx_xflags = xfs_ip2xflags(ip);
    fa.fsx_extsize = ip->i_d.di_extsize << ip->i_mount->m_sb.sb_blocklog;
    fa.fsx_projid = xfs_get_projid(ip);

    if (attr) {
        if (ip->i_afp) {
            if (ip->i_afp->if_flags & XFS_IFEXTENTS)
                fa.fsx_nextents = ip->i_afp->if_bytes /
                            sizeof(xfs_bmbt_rec_t);
            else
                fa.fsx_nextents = ip->i_d.di_anextents;
        } else
            fa.fsx_nextents = 0;
    } else {
        if (ip->i_df.if_flags & XFS_IFEXTENTS)
            fa.fsx_nextents = ip->i_df.if_bytes /
                        sizeof(xfs_bmbt_rec_t);
        else
            fa.fsx_nextents = ip->i_d.di_nextents;
    }
    xfs_iunlock(ip, XFS_ILOCK_SHARED);

    if (copy_to_user(arg, &fa, sizeof(fa)))
        return -EFAULT;
    return 0;
}

STATIC void
xfs_set_diflags(
    struct xfs_inode    *ip,
    unsigned int        xflags)
{
    unsigned int        di_flags;

    /* can't set PREALLOC this way, just preserve it */
    di_flags = (ip->i_d.di_flags & XFS_DIFLAG_PREALLOC);
    if (xflags & XFS_XFLAG_IMMUTABLE)
        di_flags |= XFS_DIFLAG_IMMUTABLE;
    if (xflags & XFS_XFLAG_APPEND)
        di_flags |= XFS_DIFLAG_APPEND;
    if (xflags & XFS_XFLAG_SYNC)
        di_flags |= XFS_DIFLAG_SYNC;
    if (xflags & XFS_XFLAG_NOATIME)
        di_flags |= XFS_DIFLAG_NOATIME;
    if (xflags & XFS_XFLAG_NODUMP)
        di_flags |= XFS_DIFLAG_NODUMP;
    if (xflags & XFS_XFLAG_PROJINHERIT)
        di_flags |= XFS_DIFLAG_PROJINHERIT;
    if (xflags & XFS_XFLAG_NODEFRAG)
        di_flags |= XFS_DIFLAG_NODEFRAG;
    if (xflags & XFS_XFLAG_FILESTREAM)
        di_flags |= XFS_DIFLAG_FILESTREAM;
    if (S_ISDIR(ip->i_d.di_mode)) {
        if (xflags & XFS_XFLAG_RTINHERIT)
            di_flags |= XFS_DIFLAG_RTINHERIT;
        if (xflags & XFS_XFLAG_NOSYMLINKS)
            di_flags |= XFS_DIFLAG_NOSYMLINKS;
        if (xflags & XFS_XFLAG_EXTSZINHERIT)
            di_flags |= XFS_DIFLAG_EXTSZINHERIT;
    } else if (S_ISREG(ip->i_d.di_mode)) {
        if (xflags & XFS_XFLAG_REALTIME)
            di_flags |= XFS_DIFLAG_REALTIME;
        if (xflags & XFS_XFLAG_EXTSIZE)
            di_flags |= XFS_DIFLAG_EXTSIZE;
    }

    ip->i_d.di_flags = di_flags;
}

STATIC void
xfs_diflags_to_linux(
    struct xfs_inode    *ip)
{
    struct inode        *inode = VFS_I(ip);
    unsigned int        xflags = xfs_ip2xflags(ip);

    if (xflags & XFS_XFLAG_IMMUTABLE)
        inode->i_flags |= S_IMMUTABLE;
    else
        inode->i_flags &= ~S_IMMUTABLE;
    if (xflags & XFS_XFLAG_APPEND)
        inode->i_flags |= S_APPEND;
    else
        inode->i_flags &= ~S_APPEND;
    if (xflags & XFS_XFLAG_SYNC)
        inode->i_flags |= S_SYNC;
    else
        inode->i_flags &= ~S_SYNC;
    if (xflags & XFS_XFLAG_NOATIME)
        inode->i_flags |= S_NOATIME;
    else
        inode->i_flags &= ~S_NOATIME;
}

#define FSX_PROJID  1
#define FSX_EXTSIZE 2
#define FSX_XFLAGS  4
#define FSX_NONBLOCK    8

STATIC int
xfs_ioctl_setattr(
    xfs_inode_t     *ip,
    struct fsxattr      *fa,
    int         mask)
{
    struct xfs_mount    *mp = ip->i_mount;
    struct xfs_trans    *tp;
    unsigned int        lock_flags = 0;
    struct xfs_dquot    *udqp = NULL;
    struct xfs_dquot    *gdqp = NULL;
    struct xfs_dquot    *olddquot = NULL;
    int         code;

    trace_xfs_ioctl_setattr(ip);

    if (mp->m_flags & XFS_MOUNT_RDONLY)
        return XFS_ERROR(EROFS);
    if (XFS_FORCED_SHUTDOWN(mp))
        return XFS_ERROR(EIO);

    /*
     * Disallow 32bit project ids when projid32bit feature is not enabled.
     */
    if ((mask & FSX_PROJID) && (fa->fsx_projid > (__uint16_t)-1) &&
            !xfs_sb_version_hasprojid32bit(&ip->i_mount->m_sb))
        return XFS_ERROR(EINVAL);

    /*
     * If disk quotas is on, we make sure that the dquots do exist on disk,
     * before we start any other transactions. Trying to do this later
     * is messy. We don't care to take a readlock to look at the ids
     * in inode here, because we can't hold it across the trans_reserve.
     * If the IDs do change before we take the ilock, we're covered
     * because the i_*dquot fields will get updated anyway.
     */
    if (XFS_IS_QUOTA_ON(mp) && (mask & FSX_PROJID)) {
        code = xfs_qm_vop_dqalloc(ip, ip->i_d.di_uid,
                     ip->i_d.di_gid, fa->fsx_projid,
                     XFS_QMOPT_PQUOTA, &udqp, &gdqp);
        if (code)
            return code;
    }

    /*
     * For the other attributes, we acquire the inode lock and
     * first do an error checking pass.
     */
    tp = xfs_trans_alloc(mp, XFS_TRANS_SETATTR_NOT_SIZE);
    code = xfs_trans_reserve(tp, 0, XFS_ICHANGE_LOG_RES(mp), 0, 0, 0);
    if (code)
        goto error_return;

    lock_flags = XFS_ILOCK_EXCL;
    xfs_ilock(ip, lock_flags);

    /*
     * CAP_FOWNER overrides the following restrictions:
     *
     * The user ID of the calling process must be equal
     * to the file owner ID, except in cases where the
     * CAP_FSETID capability is applicable.
     */
    if (current_fsuid() != ip->i_d.di_uid && !capable(CAP_FOWNER)) {
        code = XFS_ERROR(EPERM);
        goto error_return;
    }

    /*
     * Do a quota reservation only if projid is actually going to change.
     */
    if (mask & FSX_PROJID) {
        if (XFS_IS_QUOTA_RUNNING(mp) &&
            XFS_IS_PQUOTA_ON(mp) &&
            xfs_get_projid(ip) != fa->fsx_projid) {
            ASSERT(tp);
            code = xfs_qm_vop_chown_reserve(tp, ip, udqp, gdqp,
                        capable(CAP_FOWNER) ?
                        XFS_QMOPT_FORCE_RES : 0);
            if (code)   /* out of quota */
                goto error_return;
        }
    }

    if (mask & FSX_EXTSIZE) {
        /*
         * Can't change extent size if any extents are allocated.
         */
        if (ip->i_d.di_nextents &&
            ((ip->i_d.di_extsize << mp->m_sb.sb_blocklog) !=
             fa->fsx_extsize)) {
            code = XFS_ERROR(EINVAL);   /* EFBIG? */
            goto error_return;
        }

        /*
         * Extent size must be a multiple of the appropriate block
         * size, if set at all. It must also be smaller than the
         * maximum extent size supported by the filesystem.
         *
         * Also, for non-realtime files, limit the extent size hint to
         * half the size of the AGs in the filesystem so alignment
         * doesn't result in extents larger than an AG.
         */
        if (fa->fsx_extsize != 0) {
            xfs_extlen_t    size;
            xfs_fsblock_t   extsize_fsb;

            extsize_fsb = XFS_B_TO_FSB(mp, fa->fsx_extsize);
            if (extsize_fsb > MAXEXTLEN) {
                code = XFS_ERROR(EINVAL);
                goto error_return;
            }

            if (XFS_IS_REALTIME_INODE(ip) ||
                ((mask & FSX_XFLAGS) &&
                (fa->fsx_xflags & XFS_XFLAG_REALTIME))) {
                size = mp->m_sb.sb_rextsize <<
                       mp->m_sb.sb_blocklog;
            } else {
                size = mp->m_sb.sb_blocksize;
                if (extsize_fsb > mp->m_sb.sb_agblocks / 2) {
                    code = XFS_ERROR(EINVAL);
                    goto error_return;
                }
            }

            if (fa->fsx_extsize % size) {
                code = XFS_ERROR(EINVAL);
                goto error_return;
            }
        }
    }


    if (mask & FSX_XFLAGS) {
        /*
         * Can't change realtime flag if any extents are allocated.
         */
        if ((ip->i_d.di_nextents || ip->i_delayed_blks) &&
            (XFS_IS_REALTIME_INODE(ip)) !=
            (fa->fsx_xflags & XFS_XFLAG_REALTIME)) {
            code = XFS_ERROR(EINVAL);   /* EFBIG? */
            goto error_return;
        }

        /*
         * If realtime flag is set then must have realtime data.
         */
        if ((fa->fsx_xflags & XFS_XFLAG_REALTIME)) {
            if ((mp->m_sb.sb_rblocks == 0) ||
                (mp->m_sb.sb_rextsize == 0) ||
                (ip->i_d.di_extsize % mp->m_sb.sb_rextsize)) {
                code = XFS_ERROR(EINVAL);
                goto error_return;
            }
        }

        /*
         * Can't modify an immutable/append-only file unless
         * we have appropriate permission.
         */
        if ((ip->i_d.di_flags &
                (XFS_DIFLAG_IMMUTABLE|XFS_DIFLAG_APPEND) ||
             (fa->fsx_xflags &
                (XFS_XFLAG_IMMUTABLE | XFS_XFLAG_APPEND))) &&
            !capable(CAP_LINUX_IMMUTABLE)) {
            code = XFS_ERROR(EPERM);
            goto error_return;
        }
    }

    xfs_trans_ijoin(tp, ip, 0);

    /*
     * Change file ownership.  Must be the owner or privileged.
     */
    if (mask & FSX_PROJID) {
        /*
         * CAP_FSETID overrides the following restrictions:
         *
         * The set-user-ID and set-group-ID bits of a file will be
         * cleared upon successful return from chown()
         */
        if ((ip->i_d.di_mode & (S_ISUID|S_ISGID)) &&
            !capable(CAP_FSETID))
            ip->i_d.di_mode &= ~(S_ISUID|S_ISGID);

        /*
         * Change the ownerships and register quota modifications
         * in the transaction.
         */
        if (xfs_get_projid(ip) != fa->fsx_projid) {
            if (XFS_IS_QUOTA_RUNNING(mp) && XFS_IS_PQUOTA_ON(mp)) {
                olddquot = xfs_qm_vop_chown(tp, ip,
                            &ip->i_gdquot, gdqp);
            }
            xfs_set_projid(ip, fa->fsx_projid);

            /*
             * We may have to rev the inode as well as
             * the superblock version number since projids didn't
             * exist before DINODE_VERSION_2 and SB_VERSION_NLINK.
             */
            if (ip->i_d.di_version == 1)
                xfs_bump_ino_vers2(tp, ip);
        }

    }

    if (mask & FSX_EXTSIZE)
        ip->i_d.di_extsize = fa->fsx_extsize >> mp->m_sb.sb_blocklog;
    if (mask & FSX_XFLAGS) {
        xfs_set_diflags(ip, fa->fsx_xflags);
        xfs_diflags_to_linux(ip);
    }

    xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
    xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);

    XFS_STATS_INC(xs_ig_attrchg);

    /*
     * If this is a synchronous mount, make sure that the
     * transaction goes to disk before returning to the user.
     * This is slightly sub-optimal in that truncates require
     * two sync transactions instead of one for wsync filesystems.
     * One for the truncate and one for the timestamps since we
     * don't want to change the timestamps unless we're sure the
     * truncate worked.  Truncates are less than 1% of the laddis
     * mix so this probably isn't worth the trouble to optimize.
     */
    if (mp->m_flags & XFS_MOUNT_WSYNC)
        xfs_trans_set_sync(tp);
    code = xfs_trans_commit(tp, 0);
    xfs_iunlock(ip, lock_flags);

    /*
     * Release any dquot(s) the inode had kept before chown.
     */
    xfs_qm_dqrele(olddquot);
    xfs_qm_dqrele(udqp);
    xfs_qm_dqrele(gdqp);

    return code;

 error_return:
    xfs_qm_dqrele(udqp);
    xfs_qm_dqrele(gdqp);
    xfs_trans_cancel(tp, 0);
    if (lock_flags)
        xfs_iunlock(ip, lock_flags);
    return code;
}

STATIC int
xfs_ioc_fssetxattr(
    xfs_inode_t     *ip,
    struct file     *filp,
    void            __user *arg)
{
    struct fsxattr      fa;
    unsigned int        mask;
    int error;

    if (copy_from_user(&fa, arg, sizeof(fa)))
        return -EFAULT;

    mask = FSX_XFLAGS | FSX_EXTSIZE | FSX_PROJID;
    if (filp->f_flags & (O_NDELAY|O_NONBLOCK))
        mask |= FSX_NONBLOCK;

    error = mnt_want_write_file(filp);
    if (error)
        return error;
    error = xfs_ioctl_setattr(ip, &fa, mask);
    mnt_drop_write_file(filp);
    return -error;
}

STATIC int
xfs_ioc_getxflags(
    xfs_inode_t     *ip,
    void            __user *arg)
{
    unsigned int        flags;

    flags = xfs_di2lxflags(ip->i_d.di_flags);
    if (copy_to_user(arg, &flags, sizeof(flags)))
        return -EFAULT;
    return 0;
}

STATIC int
xfs_ioc_setxflags(
    xfs_inode_t     *ip,
    struct file     *filp,
    void            __user *arg)
{
    struct fsxattr      fa;
    unsigned int        flags;
    unsigned int        mask;
    int error;

    if (copy_from_user(&flags, arg, sizeof(flags)))
        return -EFAULT;

    if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
              FS_NOATIME_FL | FS_NODUMP_FL | \
              FS_SYNC_FL))
        return -EOPNOTSUPP;

    mask = FSX_XFLAGS;
    if (filp->f_flags & (O_NDELAY|O_NONBLOCK))
        mask |= FSX_NONBLOCK;
    fa.fsx_xflags = xfs_merge_ioc_xflags(flags, xfs_ip2xflags(ip));

    error = mnt_want_write_file(filp);
    if (error)
        return error;
    error = xfs_ioctl_setattr(ip, &fa, mask);
    mnt_drop_write_file(filp);
    return -error;
}

STATIC int
xfs_getbmap_format(void **ap, struct getbmapx *bmv, int *full)
{
    struct getbmap __user   *base = *ap;

    /* copy only getbmap portion (not getbmapx) */
    if (copy_to_user(base, bmv, sizeof(struct getbmap)))
        return XFS_ERROR(EFAULT);

    *ap += sizeof(struct getbmap);
    return 0;
}

STATIC int
xfs_ioc_getbmap(
    struct xfs_inode    *ip,
    int         ioflags,
    unsigned int        cmd,
    void            __user *arg)
{
    struct getbmapx     bmx;
    int         error;

    if (copy_from_user(&bmx, arg, sizeof(struct getbmapx)))
        return -XFS_ERROR(EFAULT);

    if (bmx.bmv_count < 2)
        return -XFS_ERROR(EINVAL);

    bmx.bmv_iflags = (cmd == XFS_IOC_GETBMAPA ? BMV_IF_ATTRFORK : 0);
    if (ioflags & IO_INVIS)
        bmx.bmv_iflags |= BMV_IF_NO_DMAPI_READ;

    error = xfs_getbmap(ip, &bmx, xfs_getbmap_format,
                (struct getbmap *)arg+1);
    if (error)
        return -error;

    /* copy back header - only size of getbmap */
    if (copy_to_user(arg, &bmx, sizeof(struct getbmap)))
        return -XFS_ERROR(EFAULT);
    return 0;
}

STATIC int
xfs_getbmapx_format(void **ap, struct getbmapx *bmv, int *full)
{
    struct getbmapx __user  *base = *ap;

    if (copy_to_user(base, bmv, sizeof(struct getbmapx)))
        return XFS_ERROR(EFAULT);

    *ap += sizeof(struct getbmapx);
    return 0;
}

STATIC int
xfs_ioc_getbmapx(
    struct xfs_inode    *ip,
    void            __user *arg)
{
    struct getbmapx     bmx;
    int         error;

    if (copy_from_user(&bmx, arg, sizeof(bmx)))
        return -XFS_ERROR(EFAULT);

    if (bmx.bmv_count < 2)
        return -XFS_ERROR(EINVAL);

    if (bmx.bmv_iflags & (~BMV_IF_VALID))
        return -XFS_ERROR(EINVAL);

    error = xfs_getbmap(ip, &bmx, xfs_getbmapx_format,
                (struct getbmapx *)arg+1);
    if (error)
        return -error;

    /* copy back header */
    if (copy_to_user(arg, &bmx, sizeof(struct getbmapx)))
        return -XFS_ERROR(EFAULT);

    return 0;
}

/*
 * Note: some of the ioctl's return positive numbers as a
 * byte count indicating success, such as readlink_by_handle.
 * So we don't "sign flip" like most other routines.  This means
 * true errors need to be returned as a negative value.
 */
long
xfs_file_ioctl(
    struct file     *filp,
    unsigned int        cmd,
    unsigned long       p)
{
    struct inode        *inode = filp->f_path.dentry->d_inode;
    struct xfs_inode    *ip = XFS_I(inode);
    struct xfs_mount    *mp = ip->i_mount;
    void            __user *arg = (void __user *)p;
    int         ioflags = 0;
    int         error;

    if (filp->f_mode & FMODE_NOCMTIME)
        ioflags |= IO_INVIS;

    trace_xfs_file_ioctl(ip);

    switch (cmd) {
    case FITRIM:
        return xfs_ioc_trim(mp, arg);
    case XFS_IOC_ALLOCSP:
    case XFS_IOC_FREESP:
    case XFS_IOC_RESVSP:
    case XFS_IOC_UNRESVSP:
    case XFS_IOC_ALLOCSP64:
    case XFS_IOC_FREESP64:
    case XFS_IOC_RESVSP64:
    case XFS_IOC_UNRESVSP64:
    case XFS_IOC_ZERO_RANGE: {
        xfs_flock64_t       bf;

        if (copy_from_user(&bf, arg, sizeof(bf)))
            return -XFS_ERROR(EFAULT);
        return xfs_ioc_space(ip, inode, filp, ioflags, cmd, &bf);
    }
    case XFS_IOC_DIOINFO: {
        struct dioattr  da;
        xfs_buftarg_t   *target =
            XFS_IS_REALTIME_INODE(ip) ?
            mp->m_rtdev_targp : mp->m_ddev_targp;

        da.d_mem = da.d_miniosz = 1 << target->bt_sshift;
        da.d_maxiosz = INT_MAX & ~(da.d_miniosz - 1);

        if (copy_to_user(arg, &da, sizeof(da)))
            return -XFS_ERROR(EFAULT);
        return 0;
    }

    case XFS_IOC_FSBULKSTAT_SINGLE:
    case XFS_IOC_FSBULKSTAT:
    case XFS_IOC_FSINUMBERS:
        return xfs_ioc_bulkstat(mp, cmd, arg);

    case XFS_IOC_FSGEOMETRY_V1:
        return xfs_ioc_fsgeometry_v1(mp, arg);

    case XFS_IOC_FSGEOMETRY:
        return xfs_ioc_fsgeometry(mp, arg);

    case XFS_IOC_GETVERSION:
        return put_user(inode->i_generation, (int __user *)arg);

    case XFS_IOC_FSGETXATTR:
        return xfs_ioc_fsgetxattr(ip, 0, arg);
    case XFS_IOC_FSGETXATTRA:
        return xfs_ioc_fsgetxattr(ip, 1, arg);
    case XFS_IOC_FSSETXATTR:
        return xfs_ioc_fssetxattr(ip, filp, arg);
    case XFS_IOC_GETXFLAGS:
        return xfs_ioc_getxflags(ip, arg);
    case XFS_IOC_SETXFLAGS:
        return xfs_ioc_setxflags(ip, filp, arg);

    case XFS_IOC_FSSETDM: {
        struct fsdmidata    dmi;

        if (copy_from_user(&dmi, arg, sizeof(dmi)))
            return -XFS_ERROR(EFAULT);

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

        error = xfs_set_dmattrs(ip, dmi.fsd_dmevmask,
                dmi.fsd_dmstate);
        mnt_drop_write_file(filp);
        return -error;
    }

    case XFS_IOC_GETBMAP:
    case XFS_IOC_GETBMAPA:
        return xfs_ioc_getbmap(ip, ioflags, cmd, arg);

    case XFS_IOC_GETBMAPX:
        return xfs_ioc_getbmapx(ip, arg);

    case XFS_IOC_FD_TO_HANDLE:
    case XFS_IOC_PATH_TO_HANDLE:
    case XFS_IOC_PATH_TO_FSHANDLE: {
        xfs_fsop_handlereq_t    hreq;

        if (copy_from_user(&hreq, arg, sizeof(hreq)))
            return -XFS_ERROR(EFAULT);
        return xfs_find_handle(cmd, &hreq);
    }
    case XFS_IOC_OPEN_BY_HANDLE: {
        xfs_fsop_handlereq_t    hreq;

        if (copy_from_user(&hreq, arg, sizeof(xfs_fsop_handlereq_t)))
            return -XFS_ERROR(EFAULT);
        return xfs_open_by_handle(filp, &hreq);
    }
    case XFS_IOC_FSSETDM_BY_HANDLE:
        return xfs_fssetdm_by_handle(filp, arg);

    case XFS_IOC_READLINK_BY_HANDLE: {
        xfs_fsop_handlereq_t    hreq;

        if (copy_from_user(&hreq, arg, sizeof(xfs_fsop_handlereq_t)))
            return -XFS_ERROR(EFAULT);
        return xfs_readlink_by_handle(filp, &hreq);
    }
    case XFS_IOC_ATTRLIST_BY_HANDLE:
        return xfs_attrlist_by_handle(filp, arg);

    case XFS_IOC_ATTRMULTI_BY_HANDLE:
        return xfs_attrmulti_by_handle(filp, arg);

    case XFS_IOC_SWAPEXT: {
        struct xfs_swapext  sxp;

        if (copy_from_user(&sxp, arg, sizeof(xfs_swapext_t)))
            return -XFS_ERROR(EFAULT);
        error = mnt_want_write_file(filp);
        if (error)
            return error;
        error = xfs_swapext(&sxp);
        mnt_drop_write_file(filp);
        return -error;
    }

    case XFS_IOC_FSCOUNTS: {
        xfs_fsop_counts_t out;

        error = xfs_fs_counts(mp, &out);
        if (error)
            return -error;

        if (copy_to_user(arg, &out, sizeof(out)))
            return -XFS_ERROR(EFAULT);
        return 0;
    }

    case XFS_IOC_SET_RESBLKS: {
        xfs_fsop_resblks_t inout;
        __uint64_t     in;

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

        if (mp->m_flags & XFS_MOUNT_RDONLY)
            return -XFS_ERROR(EROFS);

        if (copy_from_user(&inout, arg, sizeof(inout)))
            return -XFS_ERROR(EFAULT);

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

        /* input parameter is passed in resblks field of structure */
        in = inout.resblks;
        error = xfs_reserve_blocks(mp, &in, &inout);
        mnt_drop_write_file(filp);
        if (error)
            return -error;

        if (copy_to_user(arg, &inout, sizeof(inout)))
            return -XFS_ERROR(EFAULT);
        return 0;
    }

    case XFS_IOC_GET_RESBLKS: {
        xfs_fsop_resblks_t out;

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

        error = xfs_reserve_blocks(mp, NULL, &out);
        if (error)
            return -error;

        if (copy_to_user(arg, &out, sizeof(out)))
            return -XFS_ERROR(EFAULT);

        return 0;
    }

    case XFS_IOC_FSGROWFSDATA: {
        xfs_growfs_data_t in;

        if (copy_from_user(&in, arg, sizeof(in)))
            return -XFS_ERROR(EFAULT);

        error = mnt_want_write_file(filp);
        if (error)
            return error;
        error = xfs_growfs_data(mp, &in);
        mnt_drop_write_file(filp);
        return -error;
    }

    case XFS_IOC_FSGROWFSLOG: {
        xfs_growfs_log_t in;

        if (copy_from_user(&in, arg, sizeof(in)))
            return -XFS_ERROR(EFAULT);

        error = mnt_want_write_file(filp);
        if (error)
            return error;
        error = xfs_growfs_log(mp, &in);
        mnt_drop_write_file(filp);
        return -error;
    }

    case XFS_IOC_FSGROWFSRT: {
        xfs_growfs_rt_t in;

        if (copy_from_user(&in, arg, sizeof(in)))
            return -XFS_ERROR(EFAULT);

        error = mnt_want_write_file(filp);
        if (error)
            return error;
        error = xfs_growfs_rt(mp, &in);
        mnt_drop_write_file(filp);
        return -error;
    }

    case XFS_IOC_GOINGDOWN: {
        __uint32_t in;

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

        if (get_user(in, (__uint32_t __user *)arg))
            return -XFS_ERROR(EFAULT);

        error = xfs_fs_goingdown(mp, in);
        return -error;
    }

    case XFS_IOC_ERROR_INJECTION: {
        xfs_error_injection_t in;

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

        if (copy_from_user(&in, arg, sizeof(in)))
            return -XFS_ERROR(EFAULT);

        error = xfs_errortag_add(in.errtag, mp);
        return -error;
    }

    case XFS_IOC_ERROR_CLEARALL:
        if (!capable(CAP_SYS_ADMIN))
            return -EPERM;

        error = xfs_errortag_clearall(mp, 1);
        return -error;

    default:
        return -ENOTTY;
    }
}