/*
 *   fs/cifs/ioctl.c
 *
 *   vfs operations that deal with io control
 *
 *   Copyright (C) International Business Machines  Corp., 2005,2013
 *   Author(s): Steve French (sfrench@us.ibm.com)
 *
 *   This library is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as published
 *   by the Free Software Foundation; either version 2.1 of the License, or
 *   (at your option) any later version.
 *
 *   This library is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 *   the GNU Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public License
 *   along with this library; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <linux/fs.h>
#include <linux/file.h>
#include <linux/mount.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_debug.h"
#include "cifsfs.h"
#include "cifs_ioctl.h"
#include <linux/btrfs.h>

static int cifs_file_clone_range(unsigned int xid, struct file *src_file,
                          struct file *dst_file)
{
        struct inode *src_inode = file_inode(src_file);
        struct inode *target_inode = file_inode(dst_file);
        struct cifsFileInfo *smb_file_src;
        struct cifsFileInfo *smb_file_target;
        struct cifs_tcon *src_tcon;
        struct cifs_tcon *target_tcon;
        int rc;

        cifs_dbg(FYI, "ioctl clone range\n");

        if (!src_file->private_data || !dst_file->private_data) {
                rc = -EBADF;
                cifs_dbg(VFS, "missing cifsFileInfo on copy range src file\n");
                goto out;
        }

        rc = -EXDEV;
        smb_file_target = dst_file->private_data;
        smb_file_src = src_file->private_data;
        src_tcon = tlink_tcon(smb_file_src->tlink);
        target_tcon = tlink_tcon(smb_file_target->tlink);

        if (src_tcon->ses != target_tcon->ses) {
                cifs_dbg(VFS, "source and target of copy not on same server\n");
                goto out;
        }

        /*
         * Note: cifs case is easier than btrfs since server responsible for
         * checks for proper open modes and file type and if it wants
         * server could even support copy of range where source = target
         */
        lock_two_nondirectories(target_inode, src_inode);

        cifs_dbg(FYI, "about to flush pages\n");
        /* should we flush first and last page first */
        truncate_inode_pages(&target_inode->i_data, 0);

        if (target_tcon->ses->server->ops->clone_range)
                rc = target_tcon->ses->server->ops->clone_range(xid,
                        smb_file_src, smb_file_target, 0, src_inode->i_size, 0);
        else
                rc = -EOPNOTSUPP;

        /* force revalidate of size and timestamps of target file now
           that target is updated on the server */
        CIFS_I(target_inode)->time = 0;
        /* although unlocking in the reverse order from locking is not
           strictly necessary here it is a little cleaner to be consistent */
        unlock_two_nondirectories(src_inode, target_inode);
out:
        return rc;
}

static long cifs_ioctl_clone(unsigned int xid, struct file *dst_file,
                        unsigned long srcfd)
{
        int rc;
        struct fd src_file;
        struct inode *src_inode;

        cifs_dbg(FYI, "ioctl clone range\n");
        /* the destination must be opened for writing */
        if (!(dst_file->f_mode & FMODE_WRITE)) {
                cifs_dbg(FYI, "file target not open for write\n");
                return -EINVAL;
        }

        /* check if target volume is readonly and take reference */
        rc = mnt_want_write_file(dst_file);
        if (rc) {
                cifs_dbg(FYI, "mnt_want_write failed with rc %d\n", rc);
                return rc;
        }

        src_file = fdget(srcfd);
        if (!src_file.file) {
                rc = -EBADF;
                goto out_drop_write;
        }

        if (src_file.file->f_op->unlocked_ioctl != cifs_ioctl) {
                rc = -EBADF;
                cifs_dbg(VFS, "src file seems to be from a different filesystem type\n");
                goto out_fput;
        }

        src_inode = file_inode(src_file.file);
        rc = -EINVAL;
        if (S_ISDIR(src_inode->i_mode))
                goto out_fput;

        rc = cifs_file_clone_range(xid, src_file.file, dst_file);

out_fput:
        fdput(src_file);
out_drop_write:
        mnt_drop_write_file(dst_file);
        return rc;
}

static long smb_mnt_get_fsinfo(unsigned int xid, struct cifs_tcon *tcon,
                                void __user *arg)
{
        int rc = 0;
        struct smb_mnt_fs_info *fsinf;

        fsinf = kzalloc(sizeof(struct smb_mnt_fs_info), GFP_KERNEL);
        if (fsinf == NULL)
                return -ENOMEM;

        fsinf->version = 1;
        fsinf->protocol_id = tcon->ses->server->vals->protocol_id;
        fsinf->device_characteristics =
                        le32_to_cpu(tcon->fsDevInfo.DeviceCharacteristics);
        fsinf->device_type = le32_to_cpu(tcon->fsDevInfo.DeviceType);
        fsinf->fs_attributes = le32_to_cpu(tcon->fsAttrInfo.Attributes);
        fsinf->max_path_component =
                le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength);
#ifdef CONFIG_CIFS_SMB2
        fsinf->vol_serial_number = tcon->vol_serial_number;
        fsinf->vol_create_time = le64_to_cpu(tcon->vol_create_time);
        fsinf->share_flags = tcon->share_flags;
        fsinf->share_caps = le32_to_cpu(tcon->capabilities);
        fsinf->sector_flags = tcon->ss_flags;
        fsinf->optimal_sector_size = tcon->perf_sector_size;
        fsinf->max_bytes_chunk = tcon->max_bytes_chunk;
        fsinf->maximal_access = tcon->maximal_access;
#endif /* SMB2 */
        fsinf->cifs_posix_caps = le64_to_cpu(tcon->fsUnixInfo.Capability);

        if (copy_to_user(arg, fsinf, sizeof(struct smb_mnt_fs_info)))
                rc = -EFAULT;

        kfree(fsinf);
        return rc;
}

long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
{
        struct inode *inode = file_inode(filep);
        int rc = -ENOTTY; /* strange error - but the precedent */
        unsigned int xid;
        struct cifs_sb_info *cifs_sb;
        struct cifsFileInfo *pSMBFile = filep->private_data;
        struct cifs_tcon *tcon;
        __u64   ExtAttrBits = 0;
        __u64   caps;

        xid = get_xid();

        cifs_sb = CIFS_SB(inode->i_sb);

        switch (command) {
                case FS_IOC_GETFLAGS:
                        if (pSMBFile == NULL)
                                break;
                        tcon = tlink_tcon(pSMBFile->tlink);
                        caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
#ifdef CONFIG_CIFS_POSIX
                        if (CIFS_UNIX_EXTATTR_CAP & caps) {
                                __u64   ExtAttrMask = 0;
                                rc = CIFSGetExtAttr(xid, tcon,
                                                    pSMBFile->fid.netfid,
                                                    &ExtAttrBits, &ExtAttrMask);
                                if (rc == 0)
                                        rc = put_user(ExtAttrBits &
                                                FS_FL_USER_VISIBLE,
                                                (int __user *)arg);
                                if (rc != EOPNOTSUPP)
                                        break;
                        }
#endif /* CONFIG_CIFS_POSIX */
                        rc = 0;
                        if (CIFS_I(inode)->cifsAttrs & ATTR_COMPRESSED) {
                                /* add in the compressed bit */
                                ExtAttrBits = FS_COMPR_FL;
                                rc = put_user(ExtAttrBits & FS_FL_USER_VISIBLE,
                                              (int __user *)arg);
                        }
                        break;
                case FS_IOC_SETFLAGS:
                        if (pSMBFile == NULL)
                                break;
                        tcon = tlink_tcon(pSMBFile->tlink);
                        caps = le64_to_cpu(tcon->fsUnixInfo.Capability);

                        if (get_user(ExtAttrBits, (int __user *)arg)) {
                                rc = -EFAULT;
                                break;
                        }

                        /*
                         * if (CIFS_UNIX_EXTATTR_CAP & caps)
                         *      rc = CIFSSetExtAttr(xid, tcon,
                         *                     pSMBFile->fid.netfid,
                         *                     extAttrBits,
                         *                     &ExtAttrMask);
                         * if (rc != EOPNOTSUPP)
                         *      break;
                         */

                        /* Currently only flag we can set is compressed flag */
                        if ((ExtAttrBits & FS_COMPR_FL) == 0)
                                break;

                        /* Try to set compress flag */
                        if (tcon->ses->server->ops->set_compression) {
                                rc = tcon->ses->server->ops->set_compression(
                                                        xid, tcon, pSMBFile);
                                cifs_dbg(FYI, "set compress flag rc %d\n", rc);
                        }
                        break;
                case CIFS_IOC_COPYCHUNK_FILE:
                        rc = cifs_ioctl_clone(xid, filep, arg);
                        break;
                case CIFS_IOC_SET_INTEGRITY:
                        if (pSMBFile == NULL)
                                break;
                        tcon = tlink_tcon(pSMBFile->tlink);
                        if (tcon->ses->server->ops->set_integrity)
                                rc = tcon->ses->server->ops->set_integrity(xid,
                                                tcon, pSMBFile);
                        else
                                rc = -EOPNOTSUPP;
                        break;
                case CIFS_IOC_GET_MNT_INFO:
                        tcon = tlink_tcon(pSMBFile->tlink);
                        rc = smb_mnt_get_fsinfo(xid, tcon, (void __user *)arg);
                        break;
                default:
                        cifs_dbg(FYI, "unsupported ioctl\n");
                        break;
        }

        free_xid(xid);
        return rc;
}