LXR linux-old/fs/xfs/xfs

   1/*
   2 * Copyright (c) 2000-2002 Silicon Graphics, Inc.  All Rights Reserved.
   3 *
   4 * This program is free software; you can redistribute it and/or modify it
   5 * under the terms of version 2 of the GNU General Public License as
   6 * published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it would be useful, but
   9 * WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  11 *
  12 * Further, this software is distributed without any warranty that it is
  13 * free of the rightful claim of any third person regarding infringement
  14 * or the like.  Any license provided herein, whether implied or
  15 * otherwise, applies only to this software file.  Patent licenses, if
  16 * any, provided herein do not apply to combinations of this program with
  17 * other software, or any other product whatsoever.
  18 *
  19 * You should have received a copy of the GNU General Public License along
  20 * with this program; if not, write the Free Software Foundation, Inc., 59
  21 * Temple Place - Suite 330, Boston MA 02111-1307, USA.
  22 *
  23 * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
  24 * Mountain View, CA  94043, or:
  25 *
  26 * http://www.sgi.com
  27 *
  28 * For further information regarding this notice, see:
  29 *
  30 * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
  31 */
  32
  33#include "xfs.h"
  34#include "xfs_macros.h"
  35#include "xfs_types.h"
  36#include "xfs_inum.h"
  37#include "xfs_log.h"
  38#include "xfs_trans.h"
  39#include "xfs_sb.h"
  40#include "xfs_dir.h"
  41#include "xfs_dir2.h"
  42#include "xfs_dmapi.h"
  43#include "xfs_mount.h"
  44#include "xfs_ag.h"
  45#include "xfs_alloc_btree.h"
  46#include "xfs_bmap_btree.h"
  47#include "xfs_ialloc_btree.h"
  48#include "xfs_btree.h"
  49#include "xfs_attr_sf.h"
  50#include "xfs_dir_sf.h"
  51#include "xfs_dir2_sf.h"
  52#include "xfs_dinode.h"
  53#include "xfs_inode_item.h"
  54#include "xfs_inode.h"
  55#include "xfs_bmap.h"
  56#include "xfs_ialloc.h"
  57#include "xfs_itable.h"
  58#include "xfs_dfrag.h"
  59#include "xfs_error.h"
  60#include "xfs_mac.h"
  61#include "xfs_rw.h"
  62
  63/*
  64 * Syssgi interface for swapext
  65 */
  66int
  67xfs_swapext(
  68        xfs_swapext_t   __user *sxp)
  69{
  70        xfs_swapext_t   sx;
  71        xfs_inode_t     *ip=NULL, *tip=NULL, *ips[2];
  72        xfs_trans_t     *tp;
  73        xfs_mount_t     *mp;
  74        xfs_bstat_t     *sbp;
  75        struct file     *fp = NULL, *tfp = NULL;
  76        vnode_t         *vp, *tvp;
  77        bhv_desc_t      *bdp, *tbdp;
  78        vn_bhv_head_t   *bhp, *tbhp;
  79        uint            lock_flags=0;
  80        int             ilf_fields, tilf_fields;
  81        int             error = 0;
  82        xfs_ifork_t     tempif, *ifp, *tifp;
  83        __uint64_t      tmp;
  84        int             aforkblks = 0;
  85        int             taforkblks = 0;
  86        int             locked = 0;
  87
  88        if (copy_from_user(&sx, sxp, sizeof(sx)))
  89                return XFS_ERROR(EFAULT);
  90
  91        /* Pull information for the target fd */
  92        if (((fp = fget((int)sx.sx_fdtarget)) == NULL) ||
  93            ((vp = LINVFS_GET_VP(fp->f_dentry->d_inode)) == NULL))  {
  94                error = XFS_ERROR(EINVAL);
  95                goto error0;
  96        }
  97
  98        bhp = VN_BHV_HEAD(vp);
  99        bdp = vn_bhv_lookup(bhp, &xfs_vnodeops);
 100        if (bdp == NULL) {
 101                error = XFS_ERROR(EBADF);
 102                goto error0;
 103        } else {
 104                ip = XFS_BHVTOI(bdp);
 105        }
 106
 107        if (((tfp = fget((int)sx.sx_fdtmp)) == NULL) ||
 108            ((tvp = LINVFS_GET_VP(tfp->f_dentry->d_inode)) == NULL)) {
 109                error = XFS_ERROR(EINVAL);
 110                goto error0;
 111        }
 112
 113        tbhp = VN_BHV_HEAD(tvp);
 114        tbdp = vn_bhv_lookup(tbhp, &xfs_vnodeops);
 115        if (tbdp == NULL) {
 116                error = XFS_ERROR(EBADF);
 117                goto error0;
 118        } else {
 119                tip = XFS_BHVTOI(tbdp);
 120        }
 121
 122        if (ip->i_mount != tip->i_mount) {
 123                error =  XFS_ERROR(EINVAL);
 124                goto error0;
 125        }
 126
 127        if (ip->i_ino == tip->i_ino) {
 128                error =  XFS_ERROR(EINVAL);
 129                goto error0;
 130        }
 131
 132        mp = ip->i_mount;
 133
 134        sbp = &sx.sx_stat;
 135
 136        if (XFS_FORCED_SHUTDOWN(mp)) {
 137                error =  XFS_ERROR(EIO);
 138                goto error0;
 139        }
 140
 141        locked = 1;
 142
 143        /* Lock in i_ino order */
 144        if (ip->i_ino < tip->i_ino) {
 145                ips[0] = ip;
 146                ips[1] = tip;
 147        } else {
 148                ips[0] = tip;
 149                ips[1] = ip;
 150        }
 151        lock_flags = XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL;
 152        xfs_lock_inodes(ips, 2, 0, lock_flags);
 153
 154        /* Check permissions */
 155        error = xfs_iaccess(ip, S_IWUSR, NULL);
 156        if (error)
 157                goto error0;
 158
 159        error = xfs_iaccess(tip, S_IWUSR, NULL);
 160        if (error)
 161                goto error0;
 162
 163        /* Verify that both files have the same format */
 164        if ((ip->i_d.di_mode & S_IFMT) != (tip->i_d.di_mode & S_IFMT)) {
 165                error = XFS_ERROR(EINVAL);
 166                goto error0;
 167        }
 168
 169        /* Verify both files are either real-time or non-realtime */
 170        if ((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) !=
 171            (tip->i_d.di_flags & XFS_DIFLAG_REALTIME)) {
 172                error = XFS_ERROR(EINVAL);
 173                goto error0;
 174        }
 175
 176        /* Should never get a local format */
 177        if (ip->i_d.di_format == XFS_DINODE_FMT_LOCAL ||
 178            tip->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
 179                error = XFS_ERROR(EINVAL);
 180                goto error0;
 181        }
 182
 183        if (VN_CACHED(tvp) != 0)
 184                xfs_inval_cached_pages(XFS_ITOV(tip), &(tip->i_iocore),
 185                                                (loff_t)0, 0, 0);
 186
 187        /* Verify O_DIRECT for ftmp */
 188        if (VN_CACHED(tvp) != 0) {
 189                error = XFS_ERROR(EINVAL);
 190                goto error0;
 191        }
 192
 193        /* Verify all data are being swapped */
 194        if (sx.sx_offset != 0 ||
 195            sx.sx_length != ip->i_d.di_size ||
 196            sx.sx_length != tip->i_d.di_size) {
 197                error = XFS_ERROR(EFAULT);
 198                goto error0;
 199        }
 200
 201        /*
 202         * If the target has extended attributes, the tmp file
 203         * must also in order to ensure the correct data fork
 204         * format.
 205         */
 206        if ( XFS_IFORK_Q(ip) != XFS_IFORK_Q(tip) ) {
 207                error = XFS_ERROR(EINVAL);
 208                goto error0;
 209        }
 210
 211        /*
 212         * Compare the current change & modify times with that
 213         * passed in.  If they differ, we abort this swap.
 214         * This is the mechanism used to ensure the calling
 215         * process that the file was not changed out from
 216         * under it.
 217         */
 218        if ((sbp->bs_ctime.tv_sec != ip->i_d.di_ctime.t_sec) ||
 219            (sbp->bs_ctime.tv_nsec != ip->i_d.di_ctime.t_nsec) ||
 220            (sbp->bs_mtime.tv_sec != ip->i_d.di_mtime.t_sec) ||
 221            (sbp->bs_mtime.tv_nsec != ip->i_d.di_mtime.t_nsec)) {
 222                error = XFS_ERROR(EBUSY);
 223                goto error0;
 224        }
 225
 226        /* We need to fail if the file is memory mapped.  Once we have tossed
 227         * all existing pages, the page fault will have no option
 228         * but to go to the filesystem for pages. By making the page fault call
 229         * VOP_READ (or write in the case of autogrow) they block on the iolock
 230         * until we have switched the extents.
 231         */
 232        if (VN_MAPPED(vp)) {
 233                error = XFS_ERROR(EBUSY);
 234                goto error0;
 235        }
 236
 237        xfs_iunlock(ip, XFS_ILOCK_EXCL);
 238        xfs_iunlock(tip, XFS_ILOCK_EXCL);
 239
 240        /*
 241         * There is a race condition here since we gave up the
 242         * ilock.  However, the data fork will not change since
 243         * we have the iolock (locked for truncation too) so we
 244         * are safe.  We don't really care if non-io related
 245         * fields change.
 246         */
 247
 248        VOP_TOSS_PAGES(vp, 0, -1, FI_REMAPF);
 249
 250        tp = xfs_trans_alloc(mp, XFS_TRANS_SWAPEXT);
 251        if ((error = xfs_trans_reserve(tp, 0,
 252                                     XFS_ICHANGE_LOG_RES(mp), 0,
 253                                     0, 0))) {
 254                xfs_iunlock(ip,  XFS_IOLOCK_EXCL);
 255                xfs_iunlock(tip, XFS_IOLOCK_EXCL);
 256                xfs_trans_cancel(tp, 0);
 257                return error;
 258        }
 259        xfs_lock_inodes(ips, 2, 0, XFS_ILOCK_EXCL);
 260
 261        /*
 262         * Count the number of extended attribute blocks
 263         */
 264        if ( ((XFS_IFORK_Q(ip) != 0) && (ip->i_d.di_anextents > 0)) &&
 265             (ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
 266                error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK, &aforkblks);
 267                if (error) {
 268                        xfs_iunlock(ip,  lock_flags);
 269                        xfs_iunlock(tip, lock_flags);
 270                        xfs_trans_cancel(tp, 0);
 271                        return error;
 272                }
 273        }
 274        if ( ((XFS_IFORK_Q(tip) != 0) && (tip->i_d.di_anextents > 0)) &&
 275             (tip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
 276                error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK,
 277                        &taforkblks);
 278                if (error) {
 279                        xfs_iunlock(ip,  lock_flags);
 280                        xfs_iunlock(tip, lock_flags);
 281                        xfs_trans_cancel(tp, 0);
 282                        return error;
 283                }
 284        }
 285
 286        /*
 287         * Swap the data forks of the inodes
 288         */
 289        ifp = &ip->i_df;
 290        tifp = &tip->i_df;
 291        tempif = *ifp;  /* struct copy */
 292        *ifp = *tifp;   /* struct copy */
 293        *tifp = tempif; /* struct copy */
 294
 295        /*
 296         * Fix the on-disk inode values
 297         */
 298        tmp = (__uint64_t)ip->i_d.di_nblocks;
 299        ip->i_d.di_nblocks = tip->i_d.di_nblocks - taforkblks + aforkblks;
 300        tip->i_d.di_nblocks = tmp + taforkblks - aforkblks;
 301
 302        tmp = (__uint64_t) ip->i_d.di_nextents;
 303        ip->i_d.di_nextents = tip->i_d.di_nextents;
 304        tip->i_d.di_nextents = tmp;
 305
 306        tmp = (__uint64_t) ip->i_d.di_format;
 307        ip->i_d.di_format = tip->i_d.di_format;
 308        tip->i_d.di_format = tmp;
 309
 310        ilf_fields = XFS_ILOG_CORE;
 311
 312        switch(ip->i_d.di_format) {
 313        case XFS_DINODE_FMT_EXTENTS:
 314                /* If the extents fit in the inode, fix the
 315                 * pointer.  Otherwise it's already NULL or
 316                 * pointing to the extent.
 317                 */
 318                if (ip->i_d.di_nextents <= XFS_INLINE_EXTS) {
 319                        ifp->if_u1.if_extents =
 320                                ifp->if_u2.if_inline_ext;
 321                }
 322                ilf_fields |= XFS_ILOG_DEXT;
 323                break;
 324        case XFS_DINODE_FMT_BTREE:
 325                ilf_fields |= XFS_ILOG_DBROOT;
 326                break;
 327        }
 328
 329        tilf_fields = XFS_ILOG_CORE;
 330
 331        switch(tip->i_d.di_format) {
 332        case XFS_DINODE_FMT_EXTENTS:
 333                /* If the extents fit in the inode, fix the
 334                 * pointer.  Otherwise it's already NULL or
 335                 * pointing to the extent.
 336                 */
 337                if (tip->i_d.di_nextents <= XFS_INLINE_EXTS) {
 338                        tifp->if_u1.if_extents =
 339                                tifp->if_u2.if_inline_ext;
 340                }
 341                tilf_fields |= XFS_ILOG_DEXT;
 342                break;
 343        case XFS_DINODE_FMT_BTREE:
 344                tilf_fields |= XFS_ILOG_DBROOT;
 345                break;
 346        }
 347
 348        /*
 349         * Increment vnode ref counts since xfs_trans_commit &
 350         * xfs_trans_cancel will both unlock the inodes and
 351         * decrement the associated ref counts.
 352         */
 353        VN_HOLD(vp);
 354        VN_HOLD(tvp);
 355
 356        xfs_trans_ijoin(tp, ip, lock_flags);
 357        xfs_trans_ijoin(tp, tip, lock_flags);
 358
 359        xfs_trans_log_inode(tp, ip,  ilf_fields);
 360        xfs_trans_log_inode(tp, tip, tilf_fields);
 361
 362        /*
 363         * If this is a synchronous mount, make sure that the
 364         * transaction goes to disk before returning to the user.
 365         */
 366        if (mp->m_flags & XFS_MOUNT_WSYNC) {
 367                xfs_trans_set_sync(tp);
 368        }
 369
 370        error = xfs_trans_commit(tp, XFS_TRANS_SWAPEXT, NULL);
 371
 372        fput(fp);
 373        fput(tfp);
 374
 375        return error;
 376
 377 error0:
 378        if (locked) {
 379                xfs_iunlock(ip,  lock_flags);
 380                xfs_iunlock(tip, lock_flags);
 381        }
 382
 383        if (fp != NULL) fput(fp);
 384        if (tfp != NULL) fput(tfp);
 385
 386        return error;
 387}
 388