fs/xfs/linux-2.6/xfs_file.c

   1 /*
   2  * Copyright (c) 2000-2005 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_bit.h"
  20 #include "xfs_log.h"
  21 #include "xfs_inum.h"
  22 #include "xfs_sb.h"
  23 #include "xfs_ag.h"
  24 #include "xfs_dir2.h"
  25 #include "xfs_trans.h"
  26 #include "xfs_dmapi.h"
  27 #include "xfs_mount.h"
  28 #include "xfs_bmap_btree.h"
  29 #include "xfs_alloc_btree.h"
  30 #include "xfs_ialloc_btree.h"
  31 #include "xfs_alloc.h"
  32 #include "xfs_btree.h"
  33 #include "xfs_attr_sf.h"
  34 #include "xfs_dir2_sf.h"
  35 #include "xfs_dinode.h"
  36 #include "xfs_inode.h"
  37 #include "xfs_error.h"
  38 #include "xfs_rw.h"
  39 #include "xfs_ioctl32.h"
  40
  41 #include <linux/dcache.h>
  42 #include <linux/smp_lock.h>
  43
  44 static struct vm_operations_struct xfs_file_vm_ops;
  45 #ifdef CONFIG_XFS_DMAPI
  46 static struct vm_operations_struct xfs_dmapi_file_vm_ops;
  47 #endif
  48
  49 STATIC inline ssize_t
  50 __xfs_file_read(
  51         struct kiocb            *iocb,
  52         const struct iovec      *iov,
  53         unsigned long           nr_segs,
  54         int                     ioflags,
  55         loff_t                  pos)
  56 {
  57         struct file             *file = iocb->ki_filp;
  58         bhv_vnode_t             *vp = vn_from_inode(file->f_path.dentry->d_inode);
  59
  60         BUG_ON(iocb->ki_pos != pos);
  61         if (unlikely(file->f_flags & O_DIRECT))
  62                 ioflags |= IO_ISDIRECT;
  63         return bhv_vop_read(vp, iocb, iov, nr_segs, &iocb->ki_pos,
  64                                 ioflags, NULL);
  65 }
  66
  67 STATIC ssize_t
  68 xfs_file_aio_read(
  69         struct kiocb            *iocb,
  70         const struct iovec      *iov,
  71         unsigned long           nr_segs,
  72         loff_t                  pos)
  73 {
  74         return __xfs_file_read(iocb, iov, nr_segs, IO_ISAIO, pos);
  75 }
  76
  77 STATIC ssize_t
  78 xfs_file_aio_read_invis(
  79         struct kiocb            *iocb,
  80         const struct iovec      *iov,
  81         unsigned long           nr_segs,
  82         loff_t                  pos)
  83 {
  84         return __xfs_file_read(iocb, iov, nr_segs, IO_ISAIO|IO_INVIS, pos);
  85 }
  86
  87 STATIC inline ssize_t
  88 __xfs_file_write(
  89         struct kiocb            *iocb,
  90         const struct iovec      *iov,
  91         unsigned long           nr_segs,
  92         int                     ioflags,
  93         loff_t                  pos)
  94 {
  95         struct file     *file = iocb->ki_filp;
  96         struct inode    *inode = file->f_mapping->host;
  97         bhv_vnode_t     *vp = vn_from_inode(inode);
  98
  99         BUG_ON(iocb->ki_pos != pos);
 100         if (unlikely(file->f_flags & O_DIRECT))
 101                 ioflags |= IO_ISDIRECT;
 102         return bhv_vop_write(vp, iocb, iov, nr_segs, &iocb->ki_pos,
 103                                 ioflags, NULL);
 104 }
 105
 106 STATIC ssize_t
 107 xfs_file_aio_write(
 108         struct kiocb            *iocb,
 109         const struct iovec      *iov,
 110         unsigned long           nr_segs,
 111         loff_t                  pos)
 112 {
 113         return __xfs_file_write(iocb, iov, nr_segs, IO_ISAIO, pos);
 114 }
 115
 116 STATIC ssize_t
 117 xfs_file_aio_write_invis(
 118         struct kiocb            *iocb,
 119         const struct iovec      *iov,
 120         unsigned long           nr_segs,
 121         loff_t                  pos)
 122 {
 123         return __xfs_file_write(iocb, iov, nr_segs, IO_ISAIO|IO_INVIS, pos);
 124 }
 125
 126 STATIC ssize_t
 127 xfs_file_sendfile(
 128         struct file             *filp,
 129         loff_t                  *pos,
 130         size_t                  count,
 131         read_actor_t            actor,
 132         void                    *target)
 133 {
 134         return bhv_vop_sendfile(vn_from_inode(filp->f_path.dentry->d_inode),
 135                                 filp, pos, 0, count, actor, target, NULL);
 136 }
 137
 138 STATIC ssize_t
 139 xfs_file_sendfile_invis(
 140         struct file             *filp,
 141         loff_t                  *pos,
 142         size_t                  count,
 143         read_actor_t            actor,
 144         void                    *target)
 145 {
 146         return bhv_vop_sendfile(vn_from_inode(filp->f_path.dentry->d_inode),
 147                                 filp, pos, IO_INVIS, count, actor, target, NULL);
 148 }
 149
 150 STATIC ssize_t
 151 xfs_file_splice_read(
 152         struct file             *infilp,
 153         loff_t                  *ppos,
 154         struct pipe_inode_info  *pipe,
 155         size_t                  len,
 156         unsigned int            flags)
 157 {
 158         return bhv_vop_splice_read(vn_from_inode(infilp->f_path.dentry->d_inode),
 159                                    infilp, ppos, pipe, len, flags, 0, NULL);
 160 }
 161
 162 STATIC ssize_t
 163 xfs_file_splice_read_invis(
 164         struct file             *infilp,
 165         loff_t                  *ppos,
 166         struct pipe_inode_info  *pipe,
 167         size_t                  len,
 168         unsigned int            flags)
 169 {
 170         return bhv_vop_splice_read(vn_from_inode(infilp->f_path.dentry->d_inode),
 171                                    infilp, ppos, pipe, len, flags, IO_INVIS,
 172                                    NULL);
 173 }
 174
 175 STATIC ssize_t
 176 xfs_file_splice_write(
 177         struct pipe_inode_info  *pipe,
 178         struct file             *outfilp,
 179         loff_t                  *ppos,
 180         size_t                  len,
 181         unsigned int            flags)
 182 {
 183         return bhv_vop_splice_write(vn_from_inode(outfilp->f_path.dentry->d_inode),
 184                                     pipe, outfilp, ppos, len, flags, 0, NULL);
 185 }
 186
 187 STATIC ssize_t
 188 xfs_file_splice_write_invis(
 189         struct pipe_inode_info  *pipe,
 190         struct file             *outfilp,
 191         loff_t                  *ppos,
 192         size_t                  len,
 193         unsigned int            flags)
 194 {
 195         return bhv_vop_splice_write(vn_from_inode(outfilp->f_path.dentry->d_inode),
 196                                     pipe, outfilp, ppos, len, flags, IO_INVIS,
 197                                     NULL);
 198 }
 199
 200 STATIC int
 201 xfs_file_open(
 202         struct inode    *inode,
 203         struct file     *filp)
 204 {
 205         if (!(filp->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
 206                 return -EFBIG;
 207         return -bhv_vop_open(vn_from_inode(inode), NULL);
 208 }
 209
 210 STATIC int
 211 xfs_file_close(
 212         struct file     *filp,
 213         fl_owner_t      id)
 214 {
 215         return -bhv_vop_close(vn_from_inode(filp->f_path.dentry->d_inode), 0,
 216                                 file_count(filp) > 1 ? L_FALSE : L_TRUE, NULL);
 217 }
 218
 219 STATIC int
 220 xfs_file_release(
 221         struct inode    *inode,
 222         struct file     *filp)
 223 {
 224         bhv_vnode_t     *vp = vn_from_inode(inode);
 225
 226         if (vp)
 227                 return -bhv_vop_release(vp);
 228         return 0;
 229 }
 230
 231 STATIC int
 232 xfs_file_fsync(
 233         struct file     *filp,
 234         struct dentry   *dentry,
 235         int             datasync)
 236 {
 237         bhv_vnode_t     *vp = vn_from_inode(dentry->d_inode);
 238         int             flags = FSYNC_WAIT;
 239
 240         if (datasync)
 241                 flags |= FSYNC_DATA;
 242         if (VN_TRUNC(vp))
 243                 VUNTRUNCATE(vp);
 244         return -bhv_vop_fsync(vp, flags, NULL, (xfs_off_t)0, (xfs_off_t)-1);
 245 }
 246
 247 #ifdef CONFIG_XFS_DMAPI
 248 STATIC struct page *
 249 xfs_vm_nopage(
 250         struct vm_area_struct   *area,
 251         unsigned long           address,
 252         int                     *type)
 253 {
 254         struct inode    *inode = area->vm_file->f_path.dentry->d_inode;
 255         bhv_vnode_t     *vp = vn_from_inode(inode);
 256
 257         ASSERT_ALWAYS(vp->v_vfsp->vfs_flag & VFS_DMI);
 258         if (XFS_SEND_MMAP(XFS_VFSTOM(vp->v_vfsp), area, 0))
 259                 return NULL;
 260         return filemap_nopage(area, address, type);
 261 }
 262 #endif /* CONFIG_XFS_DMAPI */
 263
 264 STATIC int
 265 xfs_file_readdir(
 266         struct file     *filp,
 267         void            *dirent,
 268         filldir_t       filldir)
 269 {
 270         int             error = 0;
 271         bhv_vnode_t     *vp = vn_from_inode(filp->f_path.dentry->d_inode);
 272         uio_t           uio;
 273         iovec_t         iov;
 274         int             eof = 0;
 275         caddr_t         read_buf;
 276         int             namelen, size = 0;
 277         size_t          rlen = PAGE_CACHE_SIZE;
 278         xfs_off_t       start_offset, curr_offset;
 279         xfs_dirent_t    *dbp = NULL;
 280
 281         /* Try fairly hard to get memory */
 282         do {
 283                 if ((read_buf = kmalloc(rlen, GFP_KERNEL)))
 284                         break;
 285                 rlen >>= 1;
 286         } while (rlen >= 1024);
 287
 288         if (read_buf == NULL)
 289                 return -ENOMEM;
 290
 291         uio.uio_iov = &iov;
 292         uio.uio_segflg = UIO_SYSSPACE;
 293         curr_offset = filp->f_pos;
 294         if (filp->f_pos != 0x7fffffff)
 295                 uio.uio_offset = filp->f_pos;
 296         else
 297                 uio.uio_offset = 0xffffffff;
 298
 299         while (!eof) {
 300                 uio.uio_resid = iov.iov_len = rlen;
 301                 iov.iov_base = read_buf;
 302                 uio.uio_iovcnt = 1;
 303
 304                 start_offset = uio.uio_offset;
 305
 306                 error = bhv_vop_readdir(vp, &uio, NULL, &eof);
 307                 if ((uio.uio_offset == start_offset) || error) {
 308                         size = 0;
 309                         break;
 310                 }
 311
 312                 size = rlen - uio.uio_resid;
 313                 dbp = (xfs_dirent_t *)read_buf;
 314                 while (size > 0) {
 315                         namelen = strlen(dbp->d_name);
 316
 317                         if (filldir(dirent, dbp->d_name, namelen,
 318                                         (loff_t) curr_offset & 0x7fffffff,
 319                                         (ino_t) dbp->d_ino,
 320                                         DT_UNKNOWN)) {
 321                                 goto done;
 322                         }
 323                         size -= dbp->d_reclen;
 324                         curr_offset = (loff_t)dbp->d_off /* & 0x7fffffff */;
 325                         dbp = (xfs_dirent_t *)((char *)dbp + dbp->d_reclen);
 326                 }
 327         }
 328 done:
 329         if (!error) {
 330                 if (size == 0)
 331                         filp->f_pos = uio.uio_offset & 0x7fffffff;
 332                 else if (dbp)
 333                         filp->f_pos = curr_offset;
 334         }
 335
 336         kfree(read_buf);
 337         return -error;
 338 }
 339
 340 STATIC int
 341 xfs_file_mmap(
 342         struct file     *filp,
 343         struct vm_area_struct *vma)
 344 {
 345         vma->vm_ops = &xfs_file_vm_ops;
 346
 347 #ifdef CONFIG_XFS_DMAPI
 348         if (vn_from_inode(filp->f_path.dentry->d_inode)->v_vfsp->vfs_flag & VFS_DMI)
 349                 vma->vm_ops = &xfs_dmapi_file_vm_ops;
 350 #endif /* CONFIG_XFS_DMAPI */
 351
 352         file_accessed(filp);
 353         return 0;
 354 }
 355
 356 STATIC long
 357 xfs_file_ioctl(
 358         struct file     *filp,
 359         unsigned int    cmd,
 360         unsigned long   p)
 361 {
 362         int             error;
 363         struct inode    *inode = filp->f_path.dentry->d_inode;
 364         bhv_vnode_t     *vp = vn_from_inode(inode);
 365
 366         error = bhv_vop_ioctl(vp, inode, filp, 0, cmd, (void __user *)p);
 367         VMODIFY(vp);
 368
 369         /* NOTE:  some of the ioctl's return positive #'s as a
 370          *        byte count indicating success, such as
 371          *        readlink_by_handle.  So we don't "sign flip"
 372          *        like most other routines.  This means true
 373          *        errors need to be returned as a negative value.
 374          */
 375         return error;
 376 }
 377
 378 STATIC long
 379 xfs_file_ioctl_invis(
 380         struct file     *filp,
 381         unsigned int    cmd,
 382         unsigned long   p)
 383 {
 384         int             error;
 385         struct inode    *inode = filp->f_path.dentry->d_inode;
 386         bhv_vnode_t     *vp = vn_from_inode(inode);
 387
 388         error = bhv_vop_ioctl(vp, inode, filp, IO_INVIS, cmd, (void __user *)p);
 389         VMODIFY(vp);
 390
 391         /* NOTE:  some of the ioctl's return positive #'s as a
 392          *        byte count indicating success, such as
 393          *        readlink_by_handle.  So we don't "sign flip"
 394          *        like most other routines.  This means true
 395          *        errors need to be returned as a negative value.
 396          */
 397         return error;
 398 }
 399
 400 #ifdef CONFIG_XFS_DMAPI
 401 #ifdef HAVE_VMOP_MPROTECT
 402 STATIC int
 403 xfs_vm_mprotect(
 404         struct vm_area_struct *vma,
 405         unsigned int    newflags)
 406 {
 407         bhv_vnode_t     *vp = vn_from_inode(vma->vm_file->f_path.dentry->d_inode);
 408         int             error = 0;
 409
 410         if (vp->v_vfsp->vfs_flag & VFS_DMI) {
 411                 if ((vma->vm_flags & VM_MAYSHARE) &&
 412                     (newflags & VM_WRITE) && !(vma->vm_flags & VM_WRITE)) {
 413                         xfs_mount_t     *mp = XFS_VFSTOM(vp->v_vfsp);
 414
 415                         error = XFS_SEND_MMAP(mp, vma, VM_WRITE);
 416                     }
 417         }
 418         return error;
 419 }
 420 #endif /* HAVE_VMOP_MPROTECT */
 421 #endif /* CONFIG_XFS_DMAPI */
 422
 423 #ifdef HAVE_FOP_OPEN_EXEC
 424 /* If the user is attempting to execute a file that is offline then
 425  * we have to trigger a DMAPI READ event before the file is marked as busy
 426  * otherwise the invisible I/O will not be able to write to the file to bring
 427  * it back online.
 428  */
 429 STATIC int
 430 xfs_file_open_exec(
 431         struct inode    *inode)
 432 {
 433         bhv_vnode_t     *vp = vn_from_inode(inode);
 434
 435         if (unlikely(vp->v_vfsp->vfs_flag & VFS_DMI)) {
 436                 xfs_mount_t     *mp = XFS_VFSTOM(vp->v_vfsp);
 437                 xfs_inode_t     *ip = xfs_vtoi(vp);
 438
 439                 if (!ip)
 440                         return -EINVAL;
 441                 if (DM_EVENT_ENABLED(vp->v_vfsp, ip, DM_EVENT_READ))
 442                         return -XFS_SEND_DATA(mp, DM_EVENT_READ, vp,
 443                                                0, 0, 0, NULL);
 444         }
 445         return 0;
 446 }
 447 #endif /* HAVE_FOP_OPEN_EXEC */
 448
 449 const struct file_operations xfs_file_operations = {
 450         .llseek         = generic_file_llseek,
 451         .read           = do_sync_read,
 452         .write          = do_sync_write,
 453         .aio_read       = xfs_file_aio_read,
 454         .aio_write      = xfs_file_aio_write,
 455         .sendfile       = xfs_file_sendfile,
 456         .splice_read    = xfs_file_splice_read,
 457         .splice_write   = xfs_file_splice_write,
 458         .unlocked_ioctl = xfs_file_ioctl,
 459 #ifdef CONFIG_COMPAT
 460         .compat_ioctl   = xfs_file_compat_ioctl,
 461 #endif
 462         .mmap           = xfs_file_mmap,
 463         .open           = xfs_file_open,
 464         .flush          = xfs_file_close,
 465         .release        = xfs_file_release,
 466         .fsync          = xfs_file_fsync,
 467 #ifdef HAVE_FOP_OPEN_EXEC
 468         .open_exec      = xfs_file_open_exec,
 469 #endif
 470 };
 471
 472 const struct file_operations xfs_invis_file_operations = {
 473         .llseek         = generic_file_llseek,
 474         .read           = do_sync_read,
 475         .write          = do_sync_write,
 476         .aio_read       = xfs_file_aio_read_invis,
 477         .aio_write      = xfs_file_aio_write_invis,
 478         .sendfile       = xfs_file_sendfile_invis,
 479         .splice_read    = xfs_file_splice_read_invis,
 480         .splice_write   = xfs_file_splice_write_invis,
 481         .unlocked_ioctl = xfs_file_ioctl_invis,
 482 #ifdef CONFIG_COMPAT
 483         .compat_ioctl   = xfs_file_compat_invis_ioctl,
 484 #endif
 485         .mmap           = xfs_file_mmap,
 486         .open           = xfs_file_open,
 487         .flush          = xfs_file_close,
 488         .release        = xfs_file_release,
 489         .fsync          = xfs_file_fsync,
 490 };
 491
 492
 493 const struct file_operations xfs_dir_file_operations = {
 494         .read           = generic_read_dir,
 495         .readdir        = xfs_file_readdir,
 496         .unlocked_ioctl = xfs_file_ioctl,
 497 #ifdef CONFIG_COMPAT
 498         .compat_ioctl   = xfs_file_compat_ioctl,
 499 #endif
 500         .fsync          = xfs_file_fsync,
 501 };
 502
 503 static struct vm_operations_struct xfs_file_vm_ops = {
 504         .nopage         = filemap_nopage,
 505         .populate       = filemap_populate,
 506 };
 507
 508 #ifdef CONFIG_XFS_DMAPI
 509 static struct vm_operations_struct xfs_dmapi_file_vm_ops = {
 510         .nopage         = xfs_vm_nopage,
 511         .populate       = filemap_populate,
 512 #ifdef HAVE_VMOP_MPROTECT
 513         .mprotect       = xfs_vm_mprotect,
 514 #endif
 515 };
 516 #endif /* CONFIG_XFS_DMAPI */