// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_ioctl.h"
#include "xfs_alloc.h"
#include "xfs_rtalloc.h"
#include "xfs_itable.h"
#include "xfs_error.h"
#include "xfs_attr.h"
#include "xfs_bmap.h"
#include "xfs_bmap_util.h"
#include "xfs_fsops.h"
#include "xfs_discard.h"
#include "xfs_quota.h"
#include "xfs_export.h"
#include "xfs_trace.h"
#include "xfs_icache.h"
#include "xfs_symlink.h"
#include "xfs_trans.h"
#include "xfs_acl.h"
#include "xfs_btree.h"
#include <linux/fsmap.h>
#include "xfs_fsmap.h"
#include "scrub/xfs_scrub.h"
#include "xfs_sb.h"

#include <linux/capability.h>
#include <linux/cred.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 = {NULL};
        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 = file_inode(f.file);
        } else {
                error = user_lpath((const char __user *)hreq->path, &path);
                if (error)
                        return error;
                inode = d_inode(path.dentry);
        }
        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 {
                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 = inode->i_generation;
                handle.ha_fid.fid_ino = ip->i_ino;
                hsize = sizeof(xfs_handle_t);
        }

        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(file_inode(parfilp)->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 -EPERM;

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

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

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

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

        fd = get_unused_fd_flags(0);
        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;
}

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

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

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

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

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

        error = vfs_readlink(dentry, hreq->ohandle, olen);

 out_dput:
        dput(dentry);
        return error;
}

int
xfs_set_dmattrs(
        xfs_inode_t     *ip,
        uint            evmask,
        uint16_t        state)
{
        xfs_mount_t     *mp = ip->i_mount;
        xfs_trans_t     *tp;
        int             error;

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

        if (XFS_FORCED_SHUTDOWN(mp))
                return -EIO;

        error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ichange, 0, 0, 0, &tp);
        if (error)
                return error;

        xfs_ilock(ip, XFS_ILOCK_EXCL);
        xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);

        ip->i_d.di_dmevmask = evmask;
        ip->i_d.di_dmstate  = state;

        xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
        error = xfs_trans_commit(tp);

        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 -EPERM;
        if (copy_from_user(&dmhreq, arg, sizeof(xfs_fsop_setdm_handlereq_t)))
                return -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(d_inode(dentry)) || IS_APPEND(d_inode(dentry))) {
                error = -EPERM;
                goto out;
        }

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

        error = xfs_set_dmattrs(XFS_I(d_inode(dentry)), 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;
        struct xfs_fsop_attrlist_handlereq __user       *p = arg;
        xfs_fsop_attrlist_handlereq_t al_hreq;
        struct dentry           *dentry;
        char                    *kbuf;

        if (!capable(CAP_SYS_ADMIN))
                return -EPERM;
        if (copy_from_user(&al_hreq, arg, sizeof(xfs_fsop_attrlist_handlereq_t)))
                return -EFAULT;
        if (al_hreq.buflen < sizeof(struct attrlist) ||
            al_hreq.buflen > XFS_XATTR_LIST_MAX)
                return -EINVAL;

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

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

        kbuf = kmem_zalloc_large(al_hreq.buflen, KM_SLEEP);
        if (!kbuf)
                goto out_dput;

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

        if (copy_to_user(&p->pos, cursor, sizeof(attrlist_cursor_kern_t))) {
                error = -EFAULT;
                goto out_kfree;
        }

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

out_kfree:
        kmem_free(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 > XFS_XATTR_SIZE_MAX)
                return -EINVAL;
        kbuf = kmem_zalloc_large(*len, KM_SLEEP);
        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:
        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;

        if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
                return -EPERM;
        if (len > XFS_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);
        if (!error)
                xfs_forget_acl(inode, name, flags);
        kfree(kbuf);
        return error;
}

int
xfs_attrmulti_attr_remove(
        struct inode            *inode,
        unsigned char           *name,
        uint32_t                flags)
{
        int                     error;

        if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
                return -EPERM;
        error = xfs_attr_remove(XFS_I(inode), name, flags);
        if (!error)
                xfs_forget_acl(inode, name, flags);
        return error;
}

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 -EPERM;
        if (copy_from_user(&am_hreq, arg, sizeof(xfs_fsop_attrmulti_handlereq_t)))
                return -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;
        }

        error = -ENOMEM;
        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(
                                        d_inode(dentry), 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(
                                        d_inode(dentry), 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(
                                        d_inode(dentry), 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 = -EFAULT;

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

int
xfs_ioc_space(
        struct file             *filp,
        unsigned int            cmd,
        xfs_flock64_t           *bf)
{
        struct inode            *inode = file_inode(filp);
        struct xfs_inode        *ip = XFS_I(inode);
        struct iattr            iattr;
        enum xfs_prealloc_flags flags = 0;
        uint                    iolock = XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL;
        int                     error;

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

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

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

        if (filp->f_flags & O_DSYNC)
                flags |= XFS_PREALLOC_SYNC;
        if (filp->f_mode & FMODE_NOCMTIME)
                flags |= XFS_PREALLOC_INVISIBLE;

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

        xfs_ilock(ip, iolock);
        error = xfs_break_layouts(inode, &iolock, BREAK_UNMAP);
        if (error)
                goto out_unlock;

        switch (bf->l_whence) {
        case 0: /*SEEK_SET*/
                break;
        case 1: /*SEEK_CUR*/
                bf->l_start += filp->f_pos;
                break;
        case 2: /*SEEK_END*/
                bf->l_start += XFS_ISIZE(ip);
                break;
        default:
                error = -EINVAL;
                goto out_unlock;
        }

        /*
         * length of <= 0 for resv/unresv/zero is invalid.  length for
         * alloc/free is ignored completely and we have no idea what userspace
         * might have set it to, so set it to zero to allow range
         * checks to pass.
         */
        switch (cmd) {
        case XFS_IOC_ZERO_RANGE:
        case XFS_IOC_RESVSP:
        case XFS_IOC_RESVSP64:
        case XFS_IOC_UNRESVSP:
        case XFS_IOC_UNRESVSP64:
                if (bf->l_len <= 0) {
                        error = -EINVAL;
                        goto out_unlock;
                }
                break;
        default:
                bf->l_len = 0;
                break;
        }

        if (bf->l_start < 0 ||
            bf->l_start > inode->i_sb->s_maxbytes ||
            bf->l_start + bf->l_len < 0 ||
            bf->l_start + bf->l_len >= inode->i_sb->s_maxbytes) {
                error = -EINVAL;
                goto out_unlock;
        }

        switch (cmd) {
        case XFS_IOC_ZERO_RANGE:
                flags |= XFS_PREALLOC_SET;
                error = xfs_zero_file_space(ip, bf->l_start, bf->l_len);
                break;
        case XFS_IOC_RESVSP:
        case XFS_IOC_RESVSP64:
                flags |= XFS_PREALLOC_SET;
                error = xfs_alloc_file_space(ip, bf->l_start, bf->l_len,
                                                XFS_BMAPI_PREALLOC);
                break;
        case XFS_IOC_UNRESVSP:
        case XFS_IOC_UNRESVSP64:
                error = xfs_free_file_space(ip, bf->l_start, bf->l_len);
                break;
        case XFS_IOC_ALLOCSP:
        case XFS_IOC_ALLOCSP64:
        case XFS_IOC_FREESP:
        case XFS_IOC_FREESP64:
                flags |= XFS_PREALLOC_CLEAR;
                if (bf->l_start > XFS_ISIZE(ip)) {
                        error = xfs_alloc_file_space(ip, XFS_ISIZE(ip),
                                        bf->l_start - XFS_ISIZE(ip), 0);
                        if (error)
                                goto out_unlock;
                }

                iattr.ia_valid = ATTR_SIZE;
                iattr.ia_size = bf->l_start;

                error = xfs_vn_setattr_size(file_dentry(filp), &iattr);
                break;
        default:
                ASSERT(0);
                error = -EINVAL;
        }

        if (error)
                goto out_unlock;

        error = xfs_update_prealloc_flags(ip, flags);

out_unlock:
        xfs_iunlock(ip, iolock);
        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 -EIO;

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

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

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

        if (bulkreq.ubuffer == NULL)
                return -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_one(mp, inlast, bulkreq.ubuffer,
                                        sizeof(xfs_bstat_t), NULL, &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 -EFAULT;

                if (copy_to_user(bulkreq.ocount, &count, sizeof(count)))
                        return -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->m_sb, &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 -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->m_sb, &fsgeo, 4);
        if (error)
                return error;

        if (copy_to_user(arg, &fsgeo, sizeof(fsgeo)))
                return -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 |= FS_XFLAG_IMMUTABLE;
        else
                xflags &= ~FS_XFLAG_IMMUTABLE;
        if (flags & FS_APPEND_FL)
                xflags |= FS_XFLAG_APPEND;
        else
                xflags &= ~FS_XFLAG_APPEND;
        if (flags & FS_SYNC_FL)
                xflags |= FS_XFLAG_SYNC;
        else
                xflags &= ~FS_XFLAG_SYNC;
        if (flags & FS_NOATIME_FL)
                xflags |= FS_XFLAG_NOATIME;
        else
                xflags &= ~FS_XFLAG_NOATIME;
        if (flags & FS_NODUMP_FL)
                xflags |= FS_XFLAG_NODUMP;
        else
                xflags &= ~FS_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_cowextsize = ip->i_d.di_cowextsize <<
                        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 = xfs_iext_count(ip->i_afp);
                        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 = xfs_iext_count(&ip->i_df);
                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 uint16_t
xfs_flags2diflags(
        struct xfs_inode        *ip,
        unsigned int            xflags)
{
        /* can't set PREALLOC this way, just preserve it */
        uint16_t                di_flags =
                (ip->i_d.di_flags & XFS_DIFLAG_PREALLOC);

        if (xflags & FS_XFLAG_IMMUTABLE)
                di_flags |= XFS_DIFLAG_IMMUTABLE;
        if (xflags & FS_XFLAG_APPEND)
                di_flags |= XFS_DIFLAG_APPEND;
        if (xflags & FS_XFLAG_SYNC)
                di_flags |= XFS_DIFLAG_SYNC;
        if (xflags & FS_XFLAG_NOATIME)
                di_flags |= XFS_DIFLAG_NOATIME;
        if (xflags & FS_XFLAG_NODUMP)
                di_flags |= XFS_DIFLAG_NODUMP;
        if (xflags & FS_XFLAG_NODEFRAG)
                di_flags |= XFS_DIFLAG_NODEFRAG;
        if (xflags & FS_XFLAG_FILESTREAM)
                di_flags |= XFS_DIFLAG_FILESTREAM;
        if (S_ISDIR(VFS_I(ip)->i_mode)) {
                if (xflags & FS_XFLAG_RTINHERIT)
                        di_flags |= XFS_DIFLAG_RTINHERIT;
                if (xflags & FS_XFLAG_NOSYMLINKS)
                        di_flags |= XFS_DIFLAG_NOSYMLINKS;
                if (xflags & FS_XFLAG_EXTSZINHERIT)
                        di_flags |= XFS_DIFLAG_EXTSZINHERIT;
                if (xflags & FS_XFLAG_PROJINHERIT)
                        di_flags |= XFS_DIFLAG_PROJINHERIT;
        } else if (S_ISREG(VFS_I(ip)->i_mode)) {
                if (xflags & FS_XFLAG_REALTIME)
                        di_flags |= XFS_DIFLAG_REALTIME;
                if (xflags & FS_XFLAG_EXTSIZE)
                        di_flags |= XFS_DIFLAG_EXTSIZE;
        }

        return di_flags;
}

STATIC uint64_t
xfs_flags2diflags2(
        struct xfs_inode        *ip,
        unsigned int            xflags)
{
        uint64_t                di_flags2 =
                (ip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK);

        if (xflags & FS_XFLAG_DAX)
                di_flags2 |= XFS_DIFLAG2_DAX;
        if (xflags & FS_XFLAG_COWEXTSIZE)
                di_flags2 |= XFS_DIFLAG2_COWEXTSIZE;

        return di_flags2;
}

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

        if (xflags & FS_XFLAG_IMMUTABLE)
                inode->i_flags |= S_IMMUTABLE;
        else
                inode->i_flags &= ~S_IMMUTABLE;
        if (xflags & FS_XFLAG_APPEND)
                inode->i_flags |= S_APPEND;
        else
                inode->i_flags &= ~S_APPEND;
        if (xflags & FS_XFLAG_SYNC)
                inode->i_flags |= S_SYNC;
        else
                inode->i_flags &= ~S_SYNC;
        if (xflags & FS_XFLAG_NOATIME)
                inode->i_flags |= S_NOATIME;
        else
                inode->i_flags &= ~S_NOATIME;
#if 0   /* disabled until the flag switching races are sorted out */
        if (xflags & FS_XFLAG_DAX)
                inode->i_flags |= S_DAX;
        else
                inode->i_flags &= ~S_DAX;
#endif
}

static int
xfs_ioctl_setattr_xflags(
        struct xfs_trans        *tp,
        struct xfs_inode        *ip,
        struct fsxattr          *fa)
{
        struct xfs_mount        *mp = ip->i_mount;
        uint64_t                di_flags2;

        /* 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 & FS_XFLAG_REALTIME))
                return -EINVAL;

        /* If realtime flag is set then must have realtime device */
        if (fa->fsx_xflags & FS_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))
                        return -EINVAL;
        }

        /* Clear reflink if we are actually able to set the rt flag. */
        if ((fa->fsx_xflags & FS_XFLAG_REALTIME) && xfs_is_reflink_inode(ip))
                ip->i_d.di_flags2 &= ~XFS_DIFLAG2_REFLINK;

        /* Don't allow us to set DAX mode for a reflinked file for now. */
        if ((fa->fsx_xflags & FS_XFLAG_DAX) && xfs_is_reflink_inode(ip))
                return -EINVAL;

        /*
         * 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 & (FS_XFLAG_IMMUTABLE | FS_XFLAG_APPEND))) &&
            !capable(CAP_LINUX_IMMUTABLE))
                return -EPERM;

        /* diflags2 only valid for v3 inodes. */
        di_flags2 = xfs_flags2diflags2(ip, fa->fsx_xflags);
        if (di_flags2 && ip->i_d.di_version < 3)
                return -EINVAL;

        ip->i_d.di_flags = xfs_flags2diflags(ip, fa->fsx_xflags);
        ip->i_d.di_flags2 = di_flags2;

        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(mp, xs_ig_attrchg);
        return 0;
}

/*
 * If we are changing DAX flags, we have to ensure the file is clean and any
 * cached objects in the address space are invalidated and removed. This
 * requires us to lock out other IO and page faults similar to a truncate
 * operation. The locks need to be held until the transaction has been committed
 * so that the cache invalidation is atomic with respect to the DAX flag
 * manipulation.
 */
static int
xfs_ioctl_setattr_dax_invalidate(
        struct xfs_inode        *ip,
        struct fsxattr          *fa,
        int                     *join_flags)
{
        struct inode            *inode = VFS_I(ip);
        struct super_block      *sb = inode->i_sb;
        int                     error;

        *join_flags = 0;

        /*
         * It is only valid to set the DAX flag on regular files and
         * directories on filesystems where the block size is equal to the page
         * size. On directories it serves as an inherited hint so we don't
         * have to check the device for dax support or flush pagecache.
         */
        if (fa->fsx_xflags & FS_XFLAG_DAX) {
                if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)))
                        return -EINVAL;
                if (S_ISREG(inode->i_mode) &&
                    !bdev_dax_supported(xfs_find_bdev_for_inode(VFS_I(ip)),
                                sb->s_blocksize))
                        return -EINVAL;
        }

        /* If the DAX state is not changing, we have nothing to do here. */
        if ((fa->fsx_xflags & FS_XFLAG_DAX) && IS_DAX(inode))
                return 0;
        if (!(fa->fsx_xflags & FS_XFLAG_DAX) && !IS_DAX(inode))
                return 0;

        if (S_ISDIR(inode->i_mode))
                return 0;

        /* lock, flush and invalidate mapping in preparation for flag change */
        xfs_ilock(ip, XFS_MMAPLOCK_EXCL | XFS_IOLOCK_EXCL);
        error = filemap_write_and_wait(inode->i_mapping);
        if (error)
                goto out_unlock;
        error = invalidate_inode_pages2(inode->i_mapping);
        if (error)
                goto out_unlock;

        *join_flags = XFS_MMAPLOCK_EXCL | XFS_IOLOCK_EXCL;
        return 0;

out_unlock:
        xfs_iunlock(ip, XFS_MMAPLOCK_EXCL | XFS_IOLOCK_EXCL);
        return error;

}

/*
 * Set up the transaction structure for the setattr operation, checking that we
 * have permission to do so. On success, return a clean transaction and the
 * inode locked exclusively ready for further operation specific checks. On
 * failure, return an error without modifying or locking the inode.
 *
 * The inode might already be IO locked on call. If this is the case, it is
 * indicated in @join_flags and we take full responsibility for ensuring they
 * are unlocked from now on. Hence if we have an error here, we still have to
 * unlock them. Otherwise, once they are joined to the transaction, they will
 * be unlocked on commit/cancel.
 */
static struct xfs_trans *
xfs_ioctl_setattr_get_trans(
        struct xfs_inode        *ip,
        int                     join_flags)
{
        struct xfs_mount        *mp = ip->i_mount;
        struct xfs_trans        *tp;
        int                     error = -EROFS;

        if (mp->m_flags & XFS_MOUNT_RDONLY)
                goto out_unlock;
        error = -EIO;
        if (XFS_FORCED_SHUTDOWN(mp))
                goto out_unlock;

        error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ichange, 0, 0, 0, &tp);
        if (error)
                return ERR_PTR(error);

        xfs_ilock(ip, XFS_ILOCK_EXCL);
        xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL | join_flags);
        join_flags = 0;

        /*
         * 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 (!inode_owner_or_capable(VFS_I(ip))) {
                error = -EPERM;
                goto out_cancel;
        }

        if (mp->m_flags & XFS_MOUNT_WSYNC)
                xfs_trans_set_sync(tp);

        return tp;

out_cancel:
        xfs_trans_cancel(tp);
out_unlock:
        if (join_flags)
                xfs_iunlock(ip, join_flags);
        return ERR_PTR(error);
}

/*
 * extent size hint validation is somewhat cumbersome. Rules are:
 *
 * 1. extent size hint is only valid for directories and regular files
 * 2. FS_XFLAG_EXTSIZE is only valid for regular files
 * 3. FS_XFLAG_EXTSZINHERIT is only valid for directories.
 * 4. can only be changed on regular files if no extents are allocated
 * 5. can be changed on directories at any time
 * 6. extsize hint of 0 turns off hints, clears inode flags.
 * 7. Extent size must be a multiple of the appropriate block size.
 * 8. for non-realtime files, the extent size hint must be limited
 *    to half the AG size to avoid alignment extending the extent beyond the
 *    limits of the AG.
 *
 * Please keep this function in sync with xfs_scrub_inode_extsize.
 */
static int
xfs_ioctl_setattr_check_extsize(
        struct xfs_inode        *ip,
        struct fsxattr          *fa)
{
        struct xfs_mount        *mp = ip->i_mount;

        if ((fa->fsx_xflags & FS_XFLAG_EXTSIZE) && !S_ISREG(VFS_I(ip)->i_mode))
                return -EINVAL;

        if ((fa->fsx_xflags & FS_XFLAG_EXTSZINHERIT) &&
            !S_ISDIR(VFS_I(ip)->i_mode))
                return -EINVAL;

        if (S_ISREG(VFS_I(ip)->i_mode) && ip->i_d.di_nextents &&
            ((ip->i_d.di_extsize << mp->m_sb.sb_blocklog) != fa->fsx_extsize))
                return -EINVAL;

        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)
                        return -EINVAL;

                if (XFS_IS_REALTIME_INODE(ip) ||
                    (fa->fsx_xflags & FS_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)
                                return -EINVAL;
                }

                if (fa->fsx_extsize % size)
                        return -EINVAL;
        } else
                fa->fsx_xflags &= ~(FS_XFLAG_EXTSIZE | FS_XFLAG_EXTSZINHERIT);

        return 0;
}

/*
 * CoW extent size hint validation rules are:
 *
 * 1. CoW extent size hint can only be set if reflink is enabled on the fs.
 *    The inode does not have to have any shared blocks, but it must be a v3.
 * 2. FS_XFLAG_COWEXTSIZE is only valid for directories and regular files;
 *    for a directory, the hint is propagated to new files.
 * 3. Can be changed on files & directories at any time.
 * 4. CoW extsize hint of 0 turns off hints, clears inode flags.
 * 5. Extent size must be a multiple of the appropriate block size.
 * 6. The extent size hint must be limited to half the AG size to avoid
 *    alignment extending the extent beyond the limits of the AG.
 *
 * Please keep this function in sync with xfs_scrub_inode_cowextsize.
 */
static int
xfs_ioctl_setattr_check_cowextsize(
        struct xfs_inode        *ip,
        struct fsxattr          *fa)
{
        struct xfs_mount        *mp = ip->i_mount;

        if (!(fa->fsx_xflags & FS_XFLAG_COWEXTSIZE))
                return 0;

        if (!xfs_sb_version_hasreflink(&ip->i_mount->m_sb) ||
            ip->i_d.di_version != 3)
                return -EINVAL;

        if (!S_ISREG(VFS_I(ip)->i_mode) && !S_ISDIR(VFS_I(ip)->i_mode))
                return -EINVAL;

        if (fa->fsx_cowextsize != 0) {
                xfs_extlen_t    size;
                xfs_fsblock_t   cowextsize_fsb;

                cowextsize_fsb = XFS_B_TO_FSB(mp, fa->fsx_cowextsize);
                if (cowextsize_fsb > MAXEXTLEN)
                        return -EINVAL;

                size = mp->m_sb.sb_blocksize;
                if (cowextsize_fsb > mp->m_sb.sb_agblocks / 2)
                        return -EINVAL;

                if (fa->fsx_cowextsize % size)
                        return -EINVAL;
        } else
                fa->fsx_xflags &= ~FS_XFLAG_COWEXTSIZE;

        return 0;
}

static int
xfs_ioctl_setattr_check_projid(
        struct xfs_inode        *ip,
        struct fsxattr          *fa)
{
        /* Disallow 32bit project ids if projid32bit feature is not enabled. */
        if (fa->fsx_projid > (uint16_t)-1 &&
            !xfs_sb_version_hasprojid32bit(&ip->i_mount->m_sb))
                return -EINVAL;

        /*
         * Project Quota ID state is only allowed to change from within the init
         * namespace. Enforce that restriction only if we are trying to change
         * the quota ID state. Everything else is allowed in user namespaces.
         */
        if (current_user_ns() == &init_user_ns)
                return 0;

        if (xfs_get_projid(ip) != fa->fsx_projid)
                return -EINVAL;
        if ((fa->fsx_xflags & FS_XFLAG_PROJINHERIT) !=
            (ip->i_d.di_flags & XFS_DIFLAG_PROJINHERIT))
                return -EINVAL;

        return 0;
}

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

        trace_xfs_ioctl_setattr(ip);

        code = xfs_ioctl_setattr_check_projid(ip, fa);
        if (code)
                return code;

        /*
         * 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)) {
                code = xfs_qm_vop_dqalloc(ip, ip->i_d.di_uid,
                                         ip->i_d.di_gid, fa->fsx_projid,
                                         XFS_QMOPT_PQUOTA, &udqp, NULL, &pdqp);
                if (code)
                        return code;
        }

        /*
         * Changing DAX config may require inode locking for mapping
         * invalidation. These need to be held all the way to transaction commit
         * or cancel time, so need to be passed through to
         * xfs_ioctl_setattr_get_trans() so it can apply them to the join call
         * appropriately.
         */
        code = xfs_ioctl_setattr_dax_invalidate(ip, fa, &join_flags);
        if (code)
                goto error_free_dquots;

        tp = xfs_ioctl_setattr_get_trans(ip, join_flags);
        if (IS_ERR(tp)) {
                code = PTR_ERR(tp);
                goto error_free_dquots;
        }


        if (XFS_IS_QUOTA_RUNNING(mp) && XFS_IS_PQUOTA_ON(mp) &&
            xfs_get_projid(ip) != fa->fsx_projid) {
                code = xfs_qm_vop_chown_reserve(tp, ip, udqp, NULL, pdqp,
                                capable(CAP_FOWNER) ?  XFS_QMOPT_FORCE_RES : 0);
                if (code)       /* out of quota */
                        goto error_trans_cancel;
        }

        code = xfs_ioctl_setattr_check_extsize(ip, fa);
        if (code)
                goto error_trans_cancel;

        code = xfs_ioctl_setattr_check_cowextsize(ip, fa);
        if (code)
                goto error_trans_cancel;

        code = xfs_ioctl_setattr_xflags(tp, ip, fa);
        if (code)
                goto error_trans_cancel;

        /*
         * Change file ownership.  Must be the owner or privileged.  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 ((VFS_I(ip)->i_mode & (S_ISUID|S_ISGID)) &&
            !capable_wrt_inode_uidgid(VFS_I(ip), CAP_FSETID))
                VFS_I(ip)->i_mode &= ~(S_ISUID|S_ISGID);

        /* Change the ownerships and register project quota modifications */
        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_pdquot, pdqp);
                }
                ASSERT(ip->i_d.di_version > 1);
                xfs_set_projid(ip, fa->fsx_projid);
        }

        /*
         * Only set the extent size hint if we've already determined that the
         * extent size hint should be set on the inode. If no extent size flags
         * are set on the inode then unconditionally clear the extent size hint.
         */
        if (ip->i_d.di_flags & (XFS_DIFLAG_EXTSIZE | XFS_DIFLAG_EXTSZINHERIT))
                ip->i_d.di_extsize = fa->fsx_extsize >> mp->m_sb.sb_blocklog;
        else
                ip->i_d.di_extsize = 0;
        if (ip->i_d.di_version == 3 &&
            (ip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE))
                ip->i_d.di_cowextsize = fa->fsx_cowextsize >>
                                mp->m_sb.sb_blocklog;
        else
                ip->i_d.di_cowextsize = 0;

        code = xfs_trans_commit(tp);

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

        return code;

error_trans_cancel:
        xfs_trans_cancel(tp);
error_free_dquots:
        xfs_qm_dqrele(udqp);
        xfs_qm_dqrele(pdqp);
        return code;
}

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

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

        error = mnt_want_write_file(filp);
        if (error)
                return error;
        error = xfs_ioctl_setattr(ip, &fa);
        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(
        struct xfs_inode        *ip,
        struct file             *filp,
        void                    __user *arg)
{
        struct xfs_trans        *tp;
        struct fsxattr          fa;
        unsigned int            flags;
        int                     join_flags = 0;
        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;

        fa.fsx_xflags = xfs_merge_ioc_xflags(flags, xfs_ip2xflags(ip));

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

        /*
         * Changing DAX config may require inode locking for mapping
         * invalidation. These need to be held all the way to transaction commit
         * or cancel time, so need to be passed through to
         * xfs_ioctl_setattr_get_trans() so it can apply them to the join call
         * appropriately.
         */
        error = xfs_ioctl_setattr_dax_invalidate(ip, &fa, &join_flags);
        if (error)
                goto out_drop_write;

        tp = xfs_ioctl_setattr_get_trans(ip, join_flags);
        if (IS_ERR(tp)) {
                error = PTR_ERR(tp);
                goto out_drop_write;
        }

        error = xfs_ioctl_setattr_xflags(tp, ip, &fa);
        if (error) {
                xfs_trans_cancel(tp);
                goto out_drop_write;
        }

        error = xfs_trans_commit(tp);
out_drop_write:
        mnt_drop_write_file(filp);
        return error;
}

static bool
xfs_getbmap_format(
        struct kgetbmap         *p,
        struct getbmapx __user  *u,
        size_t                  recsize)
{
        if (put_user(p->bmv_offset, &u->bmv_offset) ||
            put_user(p->bmv_block, &u->bmv_block) ||
            put_user(p->bmv_length, &u->bmv_length) ||
            put_user(0, &u->bmv_count) ||
            put_user(0, &u->bmv_entries))
                return false;
        if (recsize < sizeof(struct getbmapx))
                return true;
        if (put_user(0, &u->bmv_iflags) ||
            put_user(p->bmv_oflags, &u->bmv_oflags) ||
            put_user(0, &u->bmv_unused1) ||
            put_user(0, &u->bmv_unused2))
                return false;
        return true;
}

STATIC int
xfs_ioc_getbmap(
        struct file             *file,
        unsigned int            cmd,
        void                    __user *arg)
{
        struct getbmapx         bmx = { 0 };
        struct kgetbmap         *buf;
        size_t                  recsize;
        int                     error, i;

        switch (cmd) {
        case XFS_IOC_GETBMAPA:
                bmx.bmv_iflags = BMV_IF_ATTRFORK;
                /*FALLTHRU*/
        case XFS_IOC_GETBMAP:
                if (file->f_mode & FMODE_NOCMTIME)
                        bmx.bmv_iflags |= BMV_IF_NO_DMAPI_READ;
                /* struct getbmap is a strict subset of struct getbmapx. */
                recsize = sizeof(struct getbmap);
                break;
        case XFS_IOC_GETBMAPX:
                recsize = sizeof(struct getbmapx);
                break;
        default:
                return -EINVAL;
        }

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

        if (bmx.bmv_count < 2)
                return -EINVAL;
        if (bmx.bmv_count > ULONG_MAX / recsize)
                return -ENOMEM;

        buf = kmem_zalloc_large(bmx.bmv_count * sizeof(*buf), 0);
        if (!buf)
                return -ENOMEM;

        error = xfs_getbmap(XFS_I(file_inode(file)), &bmx, buf);
        if (error)
                goto out_free_buf;

        error = -EFAULT;
        if (copy_to_user(arg, &bmx, recsize))
                goto out_free_buf;
        arg += recsize;

        for (i = 0; i < bmx.bmv_entries; i++) {
                if (!xfs_getbmap_format(buf + i, arg, recsize))
                        goto out_free_buf;
                arg += recsize;
        }

        error = 0;
out_free_buf:
        kmem_free(buf);
        return error;
}

struct getfsmap_info {
        struct xfs_mount        *mp;
        struct fsmap_head __user *data;
        unsigned int            idx;
        __u32                   last_flags;
};

STATIC int
xfs_getfsmap_format(struct xfs_fsmap *xfm, void *priv)
{
        struct getfsmap_info    *info = priv;
        struct fsmap            fm;

        trace_xfs_getfsmap_mapping(info->mp, xfm);

        info->last_flags = xfm->fmr_flags;
        xfs_fsmap_from_internal(&fm, xfm);
        if (copy_to_user(&info->data->fmh_recs[info->idx++], &fm,
                        sizeof(struct fsmap)))
                return -EFAULT;

        return 0;
}

STATIC int
xfs_ioc_getfsmap(
        struct xfs_inode        *ip,
        struct fsmap_head       __user *arg)
{
        struct getfsmap_info    info = { NULL };
        struct xfs_fsmap_head   xhead = {0};
        struct fsmap_head       head;
        bool                    aborted = false;
        int                     error;

        if (copy_from_user(&head, arg, sizeof(struct fsmap_head)))
                return -EFAULT;
        if (memchr_inv(head.fmh_reserved, 0, sizeof(head.fmh_reserved)) ||
            memchr_inv(head.fmh_keys[0].fmr_reserved, 0,
                       sizeof(head.fmh_keys[0].fmr_reserved)) ||
            memchr_inv(head.fmh_keys[1].fmr_reserved, 0,
                       sizeof(head.fmh_keys[1].fmr_reserved)))
                return -EINVAL;

        xhead.fmh_iflags = head.fmh_iflags;
        xhead.fmh_count = head.fmh_count;
        xfs_fsmap_to_internal(&xhead.fmh_keys[0], &head.fmh_keys[0]);
        xfs_fsmap_to_internal(&xhead.fmh_keys[1], &head.fmh_keys[1]);

        trace_xfs_getfsmap_low_key(ip->i_mount, &xhead.fmh_keys[0]);
        trace_xfs_getfsmap_high_key(ip->i_mount, &xhead.fmh_keys[1]);

        info.mp = ip->i_mount;
        info.data = arg;
        error = xfs_getfsmap(ip->i_mount, &xhead, xfs_getfsmap_format, &info);
        if (error == XFS_BTREE_QUERY_RANGE_ABORT) {
                error = 0;
                aborted = true;
        } else if (error)
                return error;

        /* If we didn't abort, set the "last" flag in the last fmx */
        if (!aborted && info.idx) {
                info.last_flags |= FMR_OF_LAST;
                if (copy_to_user(&info.data->fmh_recs[info.idx - 1].fmr_flags,
                                &info.last_flags, sizeof(info.last_flags)))
                        return -EFAULT;
        }

        /* copy back header */
        head.fmh_entries = xhead.fmh_entries;
        head.fmh_oflags = xhead.fmh_oflags;
        if (copy_to_user(arg, &head, sizeof(struct fsmap_head)))
                return -EFAULT;

        return 0;
}

STATIC int
xfs_ioc_scrub_metadata(
        struct xfs_inode                *ip,
        void                            __user *arg)
{
        struct xfs_scrub_metadata       scrub;
        int                             error;

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

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

        error = xfs_scrub_metadata(ip, &scrub);
        if (error)
                return error;

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

        return 0;
}

int
xfs_ioc_swapext(
        xfs_swapext_t   *sxp)
{
        xfs_inode_t     *ip, *tip;
        struct fd       f, tmp;
        int             error = 0;

        /* Pull information for the target fd */
        f = fdget((int)sxp->sx_fdtarget);
        if (!f.file) {
                error = -EINVAL;
                goto out;
        }

        if (!(f.file->f_mode & FMODE_WRITE) ||
            !(f.file->f_mode & FMODE_READ) ||
            (f.file->f_flags & O_APPEND)) {
                error = -EBADF;
                goto out_put_file;
        }

        tmp = fdget((int)sxp->sx_fdtmp);
        if (!tmp.file) {
                error = -EINVAL;
                goto out_put_file;
        }

        if (!(tmp.file->f_mode & FMODE_WRITE) ||
            !(tmp.file->f_mode & FMODE_READ) ||
            (tmp.file->f_flags & O_APPEND)) {
                error = -EBADF;
                goto out_put_tmp_file;
        }

        if (IS_SWAPFILE(file_inode(f.file)) ||
            IS_SWAPFILE(file_inode(tmp.file))) {
                error = -EINVAL;
                goto out_put_tmp_file;
        }

        /*
         * We need to ensure that the fds passed in point to XFS inodes
         * before we cast and access them as XFS structures as we have no
         * control over what the user passes us here.
         */
        if (f.file->f_op != &xfs_file_operations ||
            tmp.file->f_op != &xfs_file_operations) {
                error = -EINVAL;
                goto out_put_tmp_file;
        }

        ip = XFS_I(file_inode(f.file));
        tip = XFS_I(file_inode(tmp.file));

        if (ip->i_mount != tip->i_mount) {
                error = -EINVAL;
                goto out_put_tmp_file;
        }

        if (ip->i_ino == tip->i_ino) {
                error = -EINVAL;
                goto out_put_tmp_file;
        }

        if (XFS_FORCED_SHUTDOWN(ip->i_mount)) {
                error = -EIO;
                goto out_put_tmp_file;
        }

        error = xfs_swap_extents(ip, tip, sxp);

 out_put_tmp_file:
        fdput(tmp);
 out_put_file:
        fdput(f);
 out:
        return error;
}

static int
xfs_ioc_getlabel(
        struct xfs_mount        *mp,
        char                    __user *user_label)
{
        struct xfs_sb           *sbp = &mp->m_sb;
        char                    label[XFSLABEL_MAX + 1];

        /* Paranoia */
        BUILD_BUG_ON(sizeof(sbp->sb_fname) > FSLABEL_MAX);

        /* 1 larger than sb_fname, so this ensures a trailing NUL char */
        memset(label, 0, sizeof(label));
        spin_lock(&mp->m_sb_lock);
        strncpy(label, sbp->sb_fname, XFSLABEL_MAX);
        spin_unlock(&mp->m_sb_lock);

        if (copy_to_user(user_label, label, sizeof(label)))
                return -EFAULT;
        return 0;
}

static int
xfs_ioc_setlabel(
        struct file             *filp,
        struct xfs_mount        *mp,
        char                    __user *newlabel)
{
        struct xfs_sb           *sbp = &mp->m_sb;
        char                    label[XFSLABEL_MAX + 1];
        size_t                  len;
        int                     error;

        if (!capable(CAP_SYS_ADMIN))
                return -EPERM;
        /*
         * The generic ioctl allows up to FSLABEL_MAX chars, but XFS is much
         * smaller, at 12 bytes.  We copy one more to be sure we find the
         * (required) NULL character to test the incoming label length.
         * NB: The on disk label doesn't need to be null terminated.
         */
        if (copy_from_user(label, newlabel, XFSLABEL_MAX + 1))
                return -EFAULT;
        len = strnlen(label, XFSLABEL_MAX + 1);
        if (len > sizeof(sbp->sb_fname))
                return -EINVAL;

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

        spin_lock(&mp->m_sb_lock);
        memset(sbp->sb_fname, 0, sizeof(sbp->sb_fname));
        memcpy(sbp->sb_fname, label, len);
        spin_unlock(&mp->m_sb_lock);

        /*
         * Now we do several things to satisfy userspace.
         * In addition to normal logging of the primary superblock, we also
         * immediately write these changes to sector zero for the primary, then
         * update all backup supers (as xfs_db does for a label change), then
         * invalidate the block device page cache.  This is so that any prior
         * buffered reads from userspace (i.e. from blkid) are invalidated,
         * and userspace will see the newly-written label.
         */
        error = xfs_sync_sb_buf(mp);
        if (error)
                goto out;
        /*
         * growfs also updates backup supers so lock against that.
         */
        mutex_lock(&mp->m_growlock);
        error = xfs_update_secondary_sbs(mp);
        mutex_unlock(&mp->m_growlock);

        invalidate_bdev(mp->m_ddev_targp->bt_bdev);

out:
        mnt_drop_write_file(filp);
        return error;
}

/*
 * 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 = file_inode(filp);
        struct xfs_inode        *ip = XFS_I(inode);
        struct xfs_mount        *mp = ip->i_mount;
        void                    __user *arg = (void __user *)p;
        int                     error;

        trace_xfs_file_ioctl(ip);

        switch (cmd) {
        case FITRIM:
                return xfs_ioc_trim(mp, arg);
        case FS_IOC_GETFSLABEL:
                return xfs_ioc_getlabel(mp, arg);
        case FS_IOC_SETFSLABEL:
                return xfs_ioc_setlabel(filp, 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 -EFAULT;
                return xfs_ioc_space(filp, 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 = target->bt_logical_sectorsize;
                da.d_maxiosz = INT_MAX & ~(da.d_miniosz - 1);

                if (copy_to_user(arg, &da, sizeof(da)))
                        return -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 -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:
        case XFS_IOC_GETBMAPX:
                return xfs_ioc_getbmap(filp, cmd, arg);

        case FS_IOC_GETFSMAP:
                return xfs_ioc_getfsmap(ip, arg);

        case XFS_IOC_SCRUB_METADATA:
                return xfs_ioc_scrub_metadata(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 -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 -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 -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 -EFAULT;
                error = mnt_want_write_file(filp);
                if (error)
                        return error;
                error = xfs_ioc_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 -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 -EROFS;

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

                return 0;
        }

        case XFS_IOC_FSGROWFSDATA: {
                xfs_growfs_data_t in;

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

                return xfs_fs_goingdown(mp, in);
        }

        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 -EFAULT;

                return xfs_errortag_add(mp, in.errtag);
        }

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

                return xfs_errortag_clearall(mp);

        case XFS_IOC_FREE_EOFBLOCKS: {
                struct xfs_fs_eofblocks eofb;
                struct xfs_eofblocks keofb;

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

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

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

                error = xfs_fs_eofblocks_from_user(&eofb, &keofb);
                if (error)
                        return error;

                return xfs_icache_free_eofblocks(mp, &keofb);
        }

        default:
                return -ENOTTY;
        }
}