fs/xfs/xfs_dfrag.c

   1 /*
   2  * Copyright (c) 2000-2006 Silicon Graphics, Inc.
   3  * All Rights Reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it would be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write the Free Software Foundation,
  16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17  */
  18 #include "xfs.h"
  19 #include "xfs_fs.h"
  20 #include "xfs_types.h"
  21 #include "xfs_bit.h"
  22 #include "xfs_log.h"
  23 #include "xfs_inum.h"
  24 #include "xfs_trans.h"
  25 #include "xfs_sb.h"
  26 #include "xfs_ag.h"
  27 #include "xfs_dir2.h"
  28 #include "xfs_dmapi.h"
  29 #include "xfs_mount.h"
  30 #include "xfs_bmap_btree.h"
  31 #include "xfs_alloc_btree.h"
  32 #include "xfs_ialloc_btree.h"
  33 #include "xfs_dir2_sf.h"
  34 #include "xfs_attr_sf.h"
  35 #include "xfs_dinode.h"
  36 #include "xfs_inode.h"
  37 #include "xfs_inode_item.h"
  38 #include "xfs_bmap.h"
  39 #include "xfs_btree.h"
  40 #include "xfs_ialloc.h"
  41 #include "xfs_itable.h"
  42 #include "xfs_dfrag.h"
  43 #include "xfs_error.h"
  44 #include "xfs_mac.h"
  45 #include "xfs_rw.h"
  46
  47 /*
  48  * Syssgi interface for swapext
  49  */
  50 int
  51 xfs_swapext(
  52         xfs_swapext_t   __user *sxu)
  53 {
  54         xfs_swapext_t   *sxp;
  55         xfs_inode_t     *ip=NULL, *tip=NULL;
  56         xfs_mount_t     *mp;
  57         struct file     *fp = NULL, *tfp = NULL;
  58         bhv_vnode_t     *vp, *tvp;
  59         int             error = 0;
  60
  61         sxp = kmem_alloc(sizeof(xfs_swapext_t), KM_MAYFAIL);
  62         if (!sxp) {
  63                 error = XFS_ERROR(ENOMEM);
  64                 goto error0;
  65         }
  66
  67         if (copy_from_user(sxp, sxu, sizeof(xfs_swapext_t))) {
  68                 error = XFS_ERROR(EFAULT);
  69                 goto error0;
  70         }
  71
  72         /* Pull information for the target fd */
  73         if (((fp = fget((int)sxp->sx_fdtarget)) == NULL) ||
  74             ((vp = vn_from_inode(fp->f_dentry->d_inode)) == NULL))  {
  75                 error = XFS_ERROR(EINVAL);
  76                 goto error0;
  77         }
  78
  79         ip = xfs_vtoi(vp);
  80         if (ip == NULL) {
  81                 error = XFS_ERROR(EBADF);
  82                 goto error0;
  83         }
  84
  85         if (((tfp = fget((int)sxp->sx_fdtmp)) == NULL) ||
  86             ((tvp = vn_from_inode(tfp->f_dentry->d_inode)) == NULL)) {
  87                 error = XFS_ERROR(EINVAL);
  88                 goto error0;
  89         }
  90
  91         tip = xfs_vtoi(tvp);
  92         if (tip == NULL) {
  93                 error = XFS_ERROR(EBADF);
  94                 goto error0;
  95         }
  96
  97         if (ip->i_mount != tip->i_mount) {
  98                 error =  XFS_ERROR(EINVAL);
  99                 goto error0;
 100         }
 101
 102         if (ip->i_ino == tip->i_ino) {
 103                 error =  XFS_ERROR(EINVAL);
 104                 goto error0;
 105         }
 106
 107         mp = ip->i_mount;
 108
 109         if (XFS_FORCED_SHUTDOWN(mp)) {
 110                 error =  XFS_ERROR(EIO);
 111                 goto error0;
 112         }
 113
 114         error = XFS_SWAP_EXTENTS(mp, &ip->i_iocore, &tip->i_iocore, sxp);
 115
 116  error0:
 117         if (fp != NULL)
 118                 fput(fp);
 119         if (tfp != NULL)
 120                 fput(tfp);
 121
 122         if (sxp != NULL)
 123                 kmem_free(sxp, sizeof(xfs_swapext_t));
 124
 125         return error;
 126 }
 127
 128 int
 129 xfs_swap_extents(
 130         xfs_inode_t     *ip,
 131         xfs_inode_t     *tip,
 132         xfs_swapext_t   *sxp)
 133 {
 134         xfs_mount_t     *mp;
 135         xfs_inode_t     *ips[2];
 136         xfs_trans_t     *tp;
 137         xfs_bstat_t     *sbp = &sxp->sx_stat;
 138         bhv_vnode_t     *vp, *tvp;
 139         xfs_ifork_t     *tempifp, *ifp, *tifp;
 140         int             ilf_fields, tilf_fields;
 141         static uint     lock_flags = XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL;
 142         int             error = 0;
 143         int             aforkblks = 0;
 144         int             taforkblks = 0;
 145         __uint64_t      tmp;
 146         char            locked = 0;
 147
 148         mp = ip->i_mount;
 149
 150         tempifp = kmem_alloc(sizeof(xfs_ifork_t), KM_MAYFAIL);
 151         if (!tempifp) {
 152                 error = XFS_ERROR(ENOMEM);
 153                 goto error0;
 154         }
 155
 156         sbp = &sxp->sx_stat;
 157         vp = XFS_ITOV(ip);
 158         tvp = XFS_ITOV(tip);
 159
 160         /* Lock in i_ino order */
 161         if (ip->i_ino < tip->i_ino) {
 162                 ips[0] = ip;
 163                 ips[1] = tip;
 164         } else {
 165                 ips[0] = tip;
 166                 ips[1] = ip;
 167         }
 168
 169         xfs_lock_inodes(ips, 2, 0, lock_flags);
 170         locked = 1;
 171
 172         /* Check permissions */
 173         error = xfs_iaccess(ip, S_IWUSR, NULL);
 174         if (error)
 175                 goto error0;
 176
 177         error = xfs_iaccess(tip, S_IWUSR, NULL);
 178         if (error)
 179                 goto error0;
 180
 181         /* Verify that both files have the same format */
 182         if ((ip->i_d.di_mode & S_IFMT) != (tip->i_d.di_mode & S_IFMT)) {
 183                 error = XFS_ERROR(EINVAL);
 184                 goto error0;
 185         }
 186
 187         /* Verify both files are either real-time or non-realtime */
 188         if ((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) !=
 189             (tip->i_d.di_flags & XFS_DIFLAG_REALTIME)) {
 190                 error = XFS_ERROR(EINVAL);
 191                 goto error0;
 192         }
 193
 194         /* Should never get a local format */
 195         if (ip->i_d.di_format == XFS_DINODE_FMT_LOCAL ||
 196             tip->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
 197                 error = XFS_ERROR(EINVAL);
 198                 goto error0;
 199         }
 200
 201         if (VN_CACHED(tvp) != 0) {
 202                 xfs_inval_cached_trace(&tip->i_iocore, 0, -1, 0, -1);
 203                 bhv_vop_flushinval_pages(tvp, 0, -1, FI_REMAPF_LOCKED);
 204         }
 205
 206         /* Verify O_DIRECT for ftmp */
 207         if (VN_CACHED(tvp) != 0) {
 208                 error = XFS_ERROR(EINVAL);
 209                 goto error0;
 210         }
 211
 212         /* Verify all data are being swapped */
 213         if (sxp->sx_offset != 0 ||
 214             sxp->sx_length != ip->i_d.di_size ||
 215             sxp->sx_length != tip->i_d.di_size) {
 216                 error = XFS_ERROR(EFAULT);
 217                 goto error0;
 218         }
 219
 220         /*
 221          * If the target has extended attributes, the tmp file
 222          * must also in order to ensure the correct data fork
 223          * format.
 224          */
 225         if ( XFS_IFORK_Q(ip) != XFS_IFORK_Q(tip) ) {
 226                 error = XFS_ERROR(EINVAL);
 227                 goto error0;
 228         }
 229
 230         /*
 231          * Compare the current change & modify times with that
 232          * passed in.  If they differ, we abort this swap.
 233          * This is the mechanism used to ensure the calling
 234          * process that the file was not changed out from
 235          * under it.
 236          */
 237         if ((sbp->bs_ctime.tv_sec != ip->i_d.di_ctime.t_sec) ||
 238             (sbp->bs_ctime.tv_nsec != ip->i_d.di_ctime.t_nsec) ||
 239             (sbp->bs_mtime.tv_sec != ip->i_d.di_mtime.t_sec) ||
 240             (sbp->bs_mtime.tv_nsec != ip->i_d.di_mtime.t_nsec)) {
 241                 error = XFS_ERROR(EBUSY);
 242                 goto error0;
 243         }
 244
 245         /* We need to fail if the file is memory mapped.  Once we have tossed
 246          * all existing pages, the page fault will have no option
 247          * but to go to the filesystem for pages. By making the page fault call
 248          * vop_read (or write in the case of autogrow) they block on the iolock
 249          * until we have switched the extents.
 250          */
 251         if (VN_MAPPED(vp)) {
 252                 error = XFS_ERROR(EBUSY);
 253                 goto error0;
 254         }
 255
 256         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 257         xfs_iunlock(tip, XFS_ILOCK_EXCL);
 258
 259         /*
 260          * There is a race condition here since we gave up the
 261          * ilock.  However, the data fork will not change since
 262          * we have the iolock (locked for truncation too) so we
 263          * are safe.  We don't really care if non-io related
 264          * fields change.
 265          */
 266
 267         bhv_vop_toss_pages(vp, 0, -1, FI_REMAPF);
 268
 269         tp = xfs_trans_alloc(mp, XFS_TRANS_SWAPEXT);
 270         if ((error = xfs_trans_reserve(tp, 0,
 271                                      XFS_ICHANGE_LOG_RES(mp), 0,
 272                                      0, 0))) {
 273                 xfs_iunlock(ip,  XFS_IOLOCK_EXCL);
 274                 xfs_iunlock(tip, XFS_IOLOCK_EXCL);
 275                 xfs_trans_cancel(tp, 0);
 276                 locked = 0;
 277                 goto error0;
 278         }
 279         xfs_lock_inodes(ips, 2, 0, XFS_ILOCK_EXCL);
 280
 281         /*
 282          * Count the number of extended attribute blocks
 283          */
 284         if ( ((XFS_IFORK_Q(ip) != 0) && (ip->i_d.di_anextents > 0)) &&
 285              (ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
 286                 error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK, &aforkblks);
 287                 if (error) {
 288                         xfs_trans_cancel(tp, 0);
 289                         goto error0;
 290                 }
 291         }
 292         if ( ((XFS_IFORK_Q(tip) != 0) && (tip->i_d.di_anextents > 0)) &&
 293              (tip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
 294                 error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK,
 295                         &taforkblks);
 296                 if (error) {
 297                         xfs_trans_cancel(tp, 0);
 298                         goto error0;
 299                 }
 300         }
 301
 302         /*
 303          * Swap the data forks of the inodes
 304          */
 305         ifp = &ip->i_df;
 306         tifp = &tip->i_df;
 307         *tempifp = *ifp;        /* struct copy */
 308         *ifp = *tifp;           /* struct copy */
 309         *tifp = *tempifp;       /* struct copy */
 310
 311         /*
 312          * Fix the on-disk inode values
 313          */
 314         tmp = (__uint64_t)ip->i_d.di_nblocks;
 315         ip->i_d.di_nblocks = tip->i_d.di_nblocks - taforkblks + aforkblks;
 316         tip->i_d.di_nblocks = tmp + taforkblks - aforkblks;
 317
 318         tmp = (__uint64_t) ip->i_d.di_nextents;
 319         ip->i_d.di_nextents = tip->i_d.di_nextents;
 320         tip->i_d.di_nextents = tmp;
 321
 322         tmp = (__uint64_t) ip->i_d.di_format;
 323         ip->i_d.di_format = tip->i_d.di_format;
 324         tip->i_d.di_format = tmp;
 325
 326         ilf_fields = XFS_ILOG_CORE;
 327
 328         switch(ip->i_d.di_format) {
 329         case XFS_DINODE_FMT_EXTENTS:
 330                 /* If the extents fit in the inode, fix the
 331                  * pointer.  Otherwise it's already NULL or
 332                  * pointing to the extent.
 333                  */
 334                 if (ip->i_d.di_nextents <= XFS_INLINE_EXTS) {
 335                         ifp->if_u1.if_extents =
 336                                 ifp->if_u2.if_inline_ext;
 337                 }
 338                 ilf_fields |= XFS_ILOG_DEXT;
 339                 break;
 340         case XFS_DINODE_FMT_BTREE:
 341                 ilf_fields |= XFS_ILOG_DBROOT;
 342                 break;
 343         }
 344
 345         tilf_fields = XFS_ILOG_CORE;
 346
 347         switch(tip->i_d.di_format) {
 348         case XFS_DINODE_FMT_EXTENTS:
 349                 /* If the extents fit in the inode, fix the
 350                  * pointer.  Otherwise it's already NULL or
 351                  * pointing to the extent.
 352                  */
 353                 if (tip->i_d.di_nextents <= XFS_INLINE_EXTS) {
 354                         tifp->if_u1.if_extents =
 355                                 tifp->if_u2.if_inline_ext;
 356                 }
 357                 tilf_fields |= XFS_ILOG_DEXT;
 358                 break;
 359         case XFS_DINODE_FMT_BTREE:
 360                 tilf_fields |= XFS_ILOG_DBROOT;
 361                 break;
 362         }
 363
 364         /*
 365          * Increment vnode ref counts since xfs_trans_commit &
 366          * xfs_trans_cancel will both unlock the inodes and
 367          * decrement the associated ref counts.
 368          */
 369         VN_HOLD(vp);
 370         VN_HOLD(tvp);
 371
 372         xfs_trans_ijoin(tp, ip, lock_flags);
 373         xfs_trans_ijoin(tp, tip, lock_flags);
 374
 375         xfs_trans_log_inode(tp, ip,  ilf_fields);
 376         xfs_trans_log_inode(tp, tip, tilf_fields);
 377
 378         /*
 379          * If this is a synchronous mount, make sure that the
 380          * transaction goes to disk before returning to the user.
 381          */
 382         if (mp->m_flags & XFS_MOUNT_WSYNC) {
 383                 xfs_trans_set_sync(tp);
 384         }
 385
 386         error = xfs_trans_commit(tp, XFS_TRANS_SWAPEXT, NULL);
 387         locked = 0;
 388
 389  error0:
 390         if (locked) {
 391                 xfs_iunlock(ip,  lock_flags);
 392                 xfs_iunlock(tip, lock_flags);
 393         }
 394         if (tempifp != NULL)
 395                 kmem_free(tempifp, sizeof(xfs_ifork_t));
 396         return error;
 397 }