fs/xfs/xfs_dfrag.c

   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  */
  66 int
  67 xfs_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 }