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_dir.h"
  25 #include "xfs_dir2.h"
  26 #include "xfs_trans.h"
  27 #include "xfs_dmapi.h"
  28 #include "xfs_mount.h"
  29 #include "xfs_bmap_btree.h"
  30 #include "xfs_alloc_btree.h"
  31 #include "xfs_ialloc_btree.h"
  32 #include "xfs_alloc.h"
  33 #include "xfs_btree.h"
  34 #include "xfs_attr_sf.h"
  35 #include "xfs_dir_sf.h"
  36 #include "xfs_dir2_sf.h"
  37 #include "xfs_dinode.h"
  38 #include "xfs_inode.h"
  39 #include "xfs_error.h"
  40 #include "xfs_rw.h"
  41 #include "xfs_ioctl32.h"
  42
  43 #include <linux/dcache.h>
  44 #include <linux/smp_lock.h>
  45
  46 static struct vm_operations_struct xfs_file_vm_ops;
  47 #ifdef CONFIG_XFS_DMAPI
  48 static struct vm_operations_struct xfs_dmapi_file_vm_ops;
  49 #endif
  50
  51 STATIC inline ssize_t
  52 __xfs_file_read(
  53         struct kiocb            *iocb,
  54         char                    __user *buf,
  55         int                     ioflags,
  56         size_t                  count,
  57         loff_t                  pos)
  58 {
  59         struct iovec            iov = {buf, count};
  60         struct file             *file = iocb->ki_filp;
  61         vnode_t                 *vp = vn_from_inode(file->f_dentry->d_inode);
  62         ssize_t                 rval;
  63
  64         BUG_ON(iocb->ki_pos != pos);
  65
  66         if (unlikely(file->f_flags & O_DIRECT))
  67                 ioflags |= IO_ISDIRECT;
  68         VOP_READ(vp, iocb, &iov, 1, &iocb->ki_pos, ioflags, NULL, rval);
  69         return rval;
  70 }
  71
  72 STATIC ssize_t
  73 xfs_file_aio_read(
  74         struct kiocb            *iocb,
  75         char                    __user *buf,
  76         size_t                  count,
  77         loff_t                  pos)
  78 {
  79         return __xfs_file_read(iocb, buf, IO_ISAIO, count, pos);
  80 }
  81
  82 STATIC ssize_t
  83 xfs_file_aio_read_invis(
  84         struct kiocb            *iocb,
  85         char                    __user *buf,
  86         size_t                  count,
  87         loff_t                  pos)
  88 {
  89         return __xfs_file_read(iocb, buf, IO_ISAIO|IO_INVIS, count, pos);
  90 }
  91
  92 STATIC inline ssize_t
  93 __xfs_file_write(
  94         struct kiocb    *iocb,
  95         const char      __user *buf,
  96         int             ioflags,
  97         size_t          count,
  98         loff_t          pos)
  99 {
 100         struct iovec    iov = {(void __user *)buf, count};
 101         struct file     *file = iocb->ki_filp;
 102         struct inode    *inode = file->f_mapping->host;
 103         vnode_t         *vp = vn_from_inode(inode);
 104         ssize_t         rval;
 105
 106         BUG_ON(iocb->ki_pos != pos);
 107         if (unlikely(file->f_flags & O_DIRECT))
 108                 ioflags |= IO_ISDIRECT;
 109
 110         VOP_WRITE(vp, iocb, &iov, 1, &iocb->ki_pos, ioflags, NULL, rval);
 111         return rval;
 112 }
 113
 114 STATIC ssize_t
 115 xfs_file_aio_write(
 116         struct kiocb            *iocb,
 117         const char              __user *buf,
 118         size_t                  count,
 119         loff_t                  pos)
 120 {
 121         return __xfs_file_write(iocb, buf, IO_ISAIO, count, pos);
 122 }
 123
 124 STATIC ssize_t
 125 xfs_file_aio_write_invis(
 126         struct kiocb            *iocb,
 127         const char              __user *buf,
 128         size_t                  count,
 129         loff_t                  pos)
 130 {
 131         return __xfs_file_write(iocb, buf, IO_ISAIO|IO_INVIS, count, pos);
 132 }
 133
 134 STATIC inline ssize_t
 135 __xfs_file_readv(
 136         struct file             *file,
 137         const struct iovec      *iov,
 138         int                     ioflags,
 139         unsigned long           nr_segs,
 140         loff_t                  *ppos)
 141 {
 142         struct inode    *inode = file->f_mapping->host;
 143         vnode_t         *vp = vn_from_inode(inode);
 144         struct kiocb    kiocb;
 145         ssize_t         rval;
 146
 147         init_sync_kiocb(&kiocb, file);
 148         kiocb.ki_pos = *ppos;
 149
 150         if (unlikely(file->f_flags & O_DIRECT))
 151                 ioflags |= IO_ISDIRECT;
 152         VOP_READ(vp, &kiocb, iov, nr_segs, &kiocb.ki_pos, ioflags, NULL, rval);
 153
 154         *ppos = kiocb.ki_pos;
 155         return rval;
 156 }
 157
 158 STATIC ssize_t
 159 xfs_file_readv(
 160         struct file             *file,
 161         const struct iovec      *iov,
 162         unsigned long           nr_segs,
 163         loff_t                  *ppos)
 164 {
 165         return __xfs_file_readv(file, iov, 0, nr_segs, ppos);
 166 }
 167
 168 STATIC ssize_t
 169 xfs_file_readv_invis(
 170         struct file             *file,
 171         const struct iovec      *iov,
 172         unsigned long           nr_segs,
 173         loff_t                  *ppos)
 174 {
 175         return __xfs_file_readv(file, iov, IO_INVIS, nr_segs, ppos);
 176 }
 177
 178 STATIC inline ssize_t
 179 __xfs_file_writev(
 180         struct file             *file,
 181         const struct iovec      *iov,
 182         int                     ioflags,
 183         unsigned long           nr_segs,
 184         loff_t                  *ppos)
 185 {
 186         struct inode    *inode = file->f_mapping->host;
 187         vnode_t         *vp = vn_from_inode(inode);
 188         struct kiocb    kiocb;
 189         ssize_t         rval;
 190
 191         init_sync_kiocb(&kiocb, file);
 192         kiocb.ki_pos = *ppos;
 193         if (unlikely(file->f_flags & O_DIRECT))
 194                 ioflags |= IO_ISDIRECT;
 195
 196         VOP_WRITE(vp, &kiocb, iov, nr_segs, &kiocb.ki_pos, ioflags, NULL, rval);
 197
 198         *ppos = kiocb.ki_pos;
 199         return rval;
 200 }
 201
 202 STATIC ssize_t
 203 xfs_file_writev(
 204         struct file             *file,
 205         const struct iovec      *iov,
 206         unsigned long           nr_segs,
 207         loff_t                  *ppos)
 208 {
 209         return __xfs_file_writev(file, iov, 0, nr_segs, ppos);
 210 }
 211
 212 STATIC ssize_t
 213 xfs_file_writev_invis(
 214         struct file             *file,
 215         const struct iovec      *iov,
 216         unsigned long           nr_segs,
 217         loff_t                  *ppos)
 218 {
 219         return __xfs_file_writev(file, iov, IO_INVIS, nr_segs, ppos);
 220 }
 221
 222 STATIC ssize_t
 223 xfs_file_sendfile(
 224         struct file             *filp,
 225         loff_t                  *pos,
 226         size_t                  count,
 227         read_actor_t            actor,
 228         void                    *target)
 229 {
 230         vnode_t                 *vp = vn_from_inode(filp->f_dentry->d_inode);
 231         ssize_t                 rval;
 232
 233         VOP_SENDFILE(vp, filp, pos, 0, count, actor, target, NULL, rval);
 234         return rval;
 235 }
 236
 237 STATIC ssize_t
 238 xfs_file_sendfile_invis(
 239         struct file             *filp,
 240         loff_t                  *pos,
 241         size_t                  count,
 242         read_actor_t            actor,
 243         void                    *target)
 244 {
 245         vnode_t                 *vp = vn_from_inode(filp->f_dentry->d_inode);
 246         ssize_t                 rval;
 247
 248         VOP_SENDFILE(vp, filp, pos, IO_INVIS, count, actor, target, NULL, rval);
 249         return rval;
 250 }
 251
 252 STATIC ssize_t
 253 xfs_file_splice_read(
 254         struct file             *infilp,
 255         struct pipe_inode_info  *pipe,
 256         size_t                  len,
 257         unsigned int            flags)
 258 {
 259         vnode_t                 *vp = vn_from_inode(infilp->f_dentry->d_inode);
 260         ssize_t                 rval;
 261
 262         VOP_SPLICE_READ(vp, infilp, pipe, len, flags, 0, NULL, rval);
 263         return rval;
 264 }
 265
 266 STATIC ssize_t
 267 xfs_file_splice_read_invis(
 268         struct file             *infilp,
 269         struct pipe_inode_info  *pipe,
 270         size_t                  len,
 271         unsigned int            flags)
 272 {
 273         vnode_t                 *vp = vn_from_inode(infilp->f_dentry->d_inode);
 274         ssize_t                 rval;
 275
 276         VOP_SPLICE_READ(vp, infilp, pipe, len, flags, IO_INVIS, NULL, rval);
 277         return rval;
 278 }
 279
 280 STATIC ssize_t
 281 xfs_file_splice_write(
 282         struct pipe_inode_info  *pipe,
 283         struct file             *outfilp,
 284         size_t                  len,
 285         unsigned int            flags)
 286 {
 287         vnode_t                 *vp = vn_from_inode(outfilp->f_dentry->d_inode);
 288         ssize_t                 rval;
 289
 290         VOP_SPLICE_WRITE(vp, pipe, outfilp, len, flags, 0, NULL, rval);
 291         return rval;
 292 }
 293
 294 STATIC ssize_t
 295 xfs_file_splice_write_invis(
 296         struct pipe_inode_info  *pipe,
 297         struct file             *outfilp,
 298         size_t                  len,
 299         unsigned int            flags)
 300 {
 301         vnode_t                 *vp = vn_from_inode(outfilp->f_dentry->d_inode);
 302         ssize_t                 rval;
 303
 304         VOP_SPLICE_WRITE(vp, pipe, outfilp, len, flags, IO_INVIS, NULL, rval);
 305         return rval;
 306 }
 307
 308 STATIC int
 309 xfs_file_open(
 310         struct inode    *inode,
 311         struct file     *filp)
 312 {
 313         vnode_t         *vp = vn_from_inode(inode);
 314         int             error;
 315
 316         if (!(filp->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
 317                 return -EFBIG;
 318         VOP_OPEN(vp, NULL, error);
 319         return -error;
 320 }
 321
 322 STATIC int
 323 xfs_file_release(
 324         struct inode    *inode,
 325         struct file     *filp)
 326 {
 327         vnode_t         *vp = vn_from_inode(inode);
 328         int             error = 0;
 329
 330         if (vp)
 331                 VOP_RELEASE(vp, error);
 332         return -error;
 333 }
 334
 335 STATIC int
 336 xfs_file_fsync(
 337         struct file     *filp,
 338         struct dentry   *dentry,
 339         int             datasync)
 340 {
 341         struct inode    *inode = dentry->d_inode;
 342         vnode_t         *vp = vn_from_inode(inode);
 343         int             error;
 344         int             flags = FSYNC_WAIT;
 345
 346         if (datasync)
 347                 flags |= FSYNC_DATA;
 348         VOP_FSYNC(vp, flags, NULL, (xfs_off_t)0, (xfs_off_t)-1, error);
 349         return -error;
 350 }
 351
 352 #ifdef CONFIG_XFS_DMAPI
 353 STATIC struct page *
 354 xfs_vm_nopage(
 355         struct vm_area_struct   *area,
 356         unsigned long           address,
 357         int                     *type)
 358 {
 359         struct inode    *inode = area->vm_file->f_dentry->d_inode;
 360         vnode_t         *vp = vn_from_inode(inode);
 361         xfs_mount_t     *mp = XFS_VFSTOM(vp->v_vfsp);
 362         int             error;
 363
 364         ASSERT_ALWAYS(vp->v_vfsp->vfs_flag & VFS_DMI);
 365
 366         error = XFS_SEND_MMAP(mp, area, 0);
 367         if (error)
 368                 return NULL;
 369
 370         return filemap_nopage(area, address, type);
 371 }
 372 #endif /* CONFIG_XFS_DMAPI */
 373
 374 STATIC int
 375 xfs_file_readdir(
 376         struct file     *filp,
 377         void            *dirent,
 378         filldir_t       filldir)
 379 {
 380         int             error = 0;
 381         vnode_t         *vp = vn_from_inode(filp->f_dentry->d_inode);
 382         uio_t           uio;
 383         iovec_t         iov;
 384         int             eof = 0;
 385         caddr_t         read_buf;
 386         int             namelen, size = 0;
 387         size_t          rlen = PAGE_CACHE_SIZE;
 388         xfs_off_t       start_offset, curr_offset;
 389         xfs_dirent_t    *dbp = NULL;
 390
 391         /* Try fairly hard to get memory */
 392         do {
 393                 if ((read_buf = (caddr_t)kmalloc(rlen, GFP_KERNEL)))
 394                         break;
 395                 rlen >>= 1;
 396         } while (rlen >= 1024);
 397
 398         if (read_buf == NULL)
 399                 return -ENOMEM;
 400
 401         uio.uio_iov = &iov;
 402         uio.uio_segflg = UIO_SYSSPACE;
 403         curr_offset = filp->f_pos;
 404         if (filp->f_pos != 0x7fffffff)
 405                 uio.uio_offset = filp->f_pos;
 406         else
 407                 uio.uio_offset = 0xffffffff;
 408
 409         while (!eof) {
 410                 uio.uio_resid = iov.iov_len = rlen;
 411                 iov.iov_base = read_buf;
 412                 uio.uio_iovcnt = 1;
 413
 414                 start_offset = uio.uio_offset;
 415
 416                 VOP_READDIR(vp, &uio, NULL, &eof, error);
 417                 if ((uio.uio_offset == start_offset) || error) {
 418                         size = 0;
 419                         break;
 420                 }
 421
 422                 size = rlen - uio.uio_resid;
 423                 dbp = (xfs_dirent_t *)read_buf;
 424                 while (size > 0) {
 425                         namelen = strlen(dbp->d_name);
 426
 427                         if (filldir(dirent, dbp->d_name, namelen,
 428                                         (loff_t) curr_offset & 0x7fffffff,
 429                                         (ino_t) dbp->d_ino,
 430                                         DT_UNKNOWN)) {
 431                                 goto done;
 432                         }
 433                         size -= dbp->d_reclen;
 434                         curr_offset = (loff_t)dbp->d_off /* & 0x7fffffff */;
 435                         dbp = (xfs_dirent_t *)((char *)dbp + dbp->d_reclen);
 436                 }
 437         }
 438 done:
 439         if (!error) {
 440                 if (size == 0)
 441                         filp->f_pos = uio.uio_offset & 0x7fffffff;
 442                 else if (dbp)
 443                         filp->f_pos = curr_offset;
 444         }
 445
 446         kfree(read_buf);
 447         return -error;
 448 }
 449
 450 STATIC int
 451 xfs_file_mmap(
 452         struct file     *filp,
 453         struct vm_area_struct *vma)
 454 {
 455         struct inode    *ip = filp->f_dentry->d_inode;
 456         vnode_t         *vp = vn_from_inode(ip);
 457         vattr_t         vattr;
 458         int             error;
 459
 460         vma->vm_ops = &xfs_file_vm_ops;
 461
 462 #ifdef CONFIG_XFS_DMAPI
 463         if (vp->v_vfsp->vfs_flag & VFS_DMI) {
 464                 vma->vm_ops = &xfs_dmapi_file_vm_ops;
 465         }
 466 #endif /* CONFIG_XFS_DMAPI */
 467
 468         vattr.va_mask = XFS_AT_UPDATIME;
 469         VOP_SETATTR(vp, &vattr, XFS_AT_UPDATIME, NULL, error);
 470         if (likely(!error))
 471                 __vn_revalidate(vp, &vattr);    /* update flags */
 472         return 0;
 473 }
 474
 475
 476 STATIC long
 477 xfs_file_ioctl(
 478         struct file     *filp,
 479         unsigned int    cmd,
 480         unsigned long   arg)
 481 {
 482         int             error;
 483         struct inode    *inode = filp->f_dentry->d_inode;
 484         vnode_t         *vp = vn_from_inode(inode);
 485
 486         VOP_IOCTL(vp, inode, filp, 0, cmd, (void __user *)arg, error);
 487         VMODIFY(vp);
 488
 489         /* NOTE:  some of the ioctl's return positive #'s as a
 490          *        byte count indicating success, such as
 491          *        readlink_by_handle.  So we don't "sign flip"
 492          *        like most other routines.  This means true
 493          *        errors need to be returned as a negative value.
 494          */
 495         return error;
 496 }
 497
 498 STATIC long
 499 xfs_file_ioctl_invis(
 500         struct file     *filp,
 501         unsigned int    cmd,
 502         unsigned long   arg)
 503 {
 504         struct inode    *inode = filp->f_dentry->d_inode;
 505         vnode_t         *vp = vn_from_inode(inode);
 506         int             error;
 507
 508         VOP_IOCTL(vp, inode, filp, IO_INVIS, cmd, (void __user *)arg, error);
 509         VMODIFY(vp);
 510
 511         /* NOTE:  some of the ioctl's return positive #'s as a
 512          *        byte count indicating success, such as
 513          *        readlink_by_handle.  So we don't "sign flip"
 514          *        like most other routines.  This means true
 515          *        errors need to be returned as a negative value.
 516          */
 517         return error;
 518 }
 519
 520 #ifdef CONFIG_XFS_DMAPI
 521 #ifdef HAVE_VMOP_MPROTECT
 522 STATIC int
 523 xfs_vm_mprotect(
 524         struct vm_area_struct *vma,
 525         unsigned int    newflags)
 526 {
 527         vnode_t         *vp = vn_from_inode(vma->vm_file->f_dentry->d_inode);
 528         int             error = 0;
 529
 530         if (vp->v_vfsp->vfs_flag & VFS_DMI) {
 531                 if ((vma->vm_flags & VM_MAYSHARE) &&
 532                     (newflags & VM_WRITE) && !(vma->vm_flags & VM_WRITE)) {
 533                         xfs_mount_t     *mp = XFS_VFSTOM(vp->v_vfsp);
 534
 535                         error = XFS_SEND_MMAP(mp, vma, VM_WRITE);
 536                     }
 537         }
 538         return error;
 539 }
 540 #endif /* HAVE_VMOP_MPROTECT */
 541 #endif /* CONFIG_XFS_DMAPI */
 542
 543 #ifdef HAVE_FOP_OPEN_EXEC
 544 /* If the user is attempting to execute a file that is offline then
 545  * we have to trigger a DMAPI READ event before the file is marked as busy
 546  * otherwise the invisible I/O will not be able to write to the file to bring
 547  * it back online.
 548  */
 549 STATIC int
 550 xfs_file_open_exec(
 551         struct inode    *inode)
 552 {
 553         vnode_t         *vp = vn_from_inode(inode);
 554         xfs_mount_t     *mp = XFS_VFSTOM(vp->v_vfsp);
 555         int             error = 0;
 556         xfs_inode_t     *ip;
 557
 558         if (vp->v_vfsp->vfs_flag & VFS_DMI) {
 559                 ip = xfs_vtoi(vp);
 560                 if (!ip) {
 561                         error = -EINVAL;
 562                         goto open_exec_out;
 563                 }
 564                 if (DM_EVENT_ENABLED(vp->v_vfsp, ip, DM_EVENT_READ)) {
 565                         error = -XFS_SEND_DATA(mp, DM_EVENT_READ, vp,
 566                                                0, 0, 0, NULL);
 567                 }
 568         }
 569 open_exec_out:
 570         return error;
 571 }
 572 #endif /* HAVE_FOP_OPEN_EXEC */
 573
 574 const struct file_operations xfs_file_operations = {
 575         .llseek         = generic_file_llseek,
 576         .read           = do_sync_read,
 577         .write          = do_sync_write,
 578         .readv          = xfs_file_readv,
 579         .writev         = xfs_file_writev,
 580         .aio_read       = xfs_file_aio_read,
 581         .aio_write      = xfs_file_aio_write,
 582         .sendfile       = xfs_file_sendfile,
 583         .splice_read    = xfs_file_splice_read,
 584         .splice_write   = xfs_file_splice_write,
 585         .unlocked_ioctl = xfs_file_ioctl,
 586 #ifdef CONFIG_COMPAT
 587         .compat_ioctl   = xfs_file_compat_ioctl,
 588 #endif
 589         .mmap           = xfs_file_mmap,
 590         .open           = xfs_file_open,
 591         .release        = xfs_file_release,
 592         .fsync          = xfs_file_fsync,
 593 #ifdef HAVE_FOP_OPEN_EXEC
 594         .open_exec      = xfs_file_open_exec,
 595 #endif
 596 };
 597
 598 const struct file_operations xfs_invis_file_operations = {
 599         .llseek         = generic_file_llseek,
 600         .read           = do_sync_read,
 601         .write          = do_sync_write,
 602         .readv          = xfs_file_readv_invis,
 603         .writev         = xfs_file_writev_invis,
 604         .aio_read       = xfs_file_aio_read_invis,
 605         .aio_write      = xfs_file_aio_write_invis,
 606         .sendfile       = xfs_file_sendfile_invis,
 607         .splice_read    = xfs_file_splice_read_invis,
 608         .splice_write   = xfs_file_splice_write_invis,
 609         .unlocked_ioctl = xfs_file_ioctl_invis,
 610 #ifdef CONFIG_COMPAT
 611         .compat_ioctl   = xfs_file_compat_invis_ioctl,
 612 #endif
 613         .mmap           = xfs_file_mmap,
 614         .open           = xfs_file_open,
 615         .release        = xfs_file_release,
 616         .fsync          = xfs_file_fsync,
 617 };
 618
 619
 620 const struct file_operations xfs_dir_file_operations = {
 621         .read           = generic_read_dir,
 622         .readdir        = xfs_file_readdir,
 623         .unlocked_ioctl = xfs_file_ioctl,
 624 #ifdef CONFIG_COMPAT
 625         .compat_ioctl   = xfs_file_compat_ioctl,
 626 #endif
 627         .fsync          = xfs_file_fsync,
 628 };
 629
 630 static struct vm_operations_struct xfs_file_vm_ops = {
 631         .nopage         = filemap_nopage,
 632         .populate       = filemap_populate,
 633 };
 634
 635 #ifdef CONFIG_XFS_DMAPI
 636 static struct vm_operations_struct xfs_dmapi_file_vm_ops = {
 637         .nopage         = xfs_vm_nopage,
 638         .populate       = filemap_populate,
 639 #ifdef HAVE_VMOP_MPROTECT
 640         .mprotect       = xfs_vm_mprotect,
 641 #endif
 642 };
 643 #endif /* CONFIG_XFS_DMAPI */