fs/fuse/file.c

   1 /*
   2   FUSE: Filesystem in Userspace
   3   Copyright (C) 2001-2006  Miklos Szeredi <miklos@szeredi.hu>
   4
   5   This program can be distributed under the terms of the GNU GPL.
   6   See the file COPYING.
   7 */
   8
   9 #include "fuse_i.h"
  10
  11 #include <linux/pagemap.h>
  12 #include <linux/slab.h>
  13 #include <linux/kernel.h>
  14 #include <linux/sched.h>
  15
  16 static const struct file_operations fuse_direct_io_file_operations;
  17
  18 static int fuse_send_open(struct inode *inode, struct file *file, int isdir,
  19                           struct fuse_open_out *outargp)
  20 {
  21         struct fuse_conn *fc = get_fuse_conn(inode);
  22         struct fuse_open_in inarg;
  23         struct fuse_req *req;
  24         int err;
  25
  26         req = fuse_get_req(fc);
  27         if (IS_ERR(req))
  28                 return PTR_ERR(req);
  29
  30         memset(&inarg, 0, sizeof(inarg));
  31         inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
  32         req->in.h.opcode = isdir ? FUSE_OPENDIR : FUSE_OPEN;
  33         req->in.h.nodeid = get_node_id(inode);
  34         req->in.numargs = 1;
  35         req->in.args[0].size = sizeof(inarg);
  36         req->in.args[0].value = &inarg;
  37         req->out.numargs = 1;
  38         req->out.args[0].size = sizeof(*outargp);
  39         req->out.args[0].value = outargp;
  40         request_send(fc, req);
  41         err = req->out.h.error;
  42         fuse_put_request(fc, req);
  43
  44         return err;
  45 }
  46
  47 struct fuse_file *fuse_file_alloc(void)
  48 {
  49         struct fuse_file *ff;
  50         ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL);
  51         if (ff) {
  52                 ff->reserved_req = fuse_request_alloc();
  53                 if (!ff->reserved_req) {
  54                         kfree(ff);
  55                         ff = NULL;
  56                 }
  57         }
  58         return ff;
  59 }
  60
  61 void fuse_file_free(struct fuse_file *ff)
  62 {
  63         fuse_request_free(ff->reserved_req);
  64         kfree(ff);
  65 }
  66
  67 void fuse_finish_open(struct inode *inode, struct file *file,
  68                       struct fuse_file *ff, struct fuse_open_out *outarg)
  69 {
  70         if (outarg->open_flags & FOPEN_DIRECT_IO)
  71                 file->f_op = &fuse_direct_io_file_operations;
  72         if (!(outarg->open_flags & FOPEN_KEEP_CACHE))
  73                 invalidate_mapping_pages(inode->i_mapping, 0, -1);
  74         ff->fh = outarg->fh;
  75         file->private_data = ff;
  76 }
  77
  78 int fuse_open_common(struct inode *inode, struct file *file, int isdir)
  79 {
  80         struct fuse_open_out outarg;
  81         struct fuse_file *ff;
  82         int err;
  83
  84         /* VFS checks this, but only _after_ ->open() */
  85         if (file->f_flags & O_DIRECT)
  86                 return -EINVAL;
  87
  88         err = generic_file_open(inode, file);
  89         if (err)
  90                 return err;
  91
  92         /* If opening the root node, no lookup has been performed on
  93            it, so the attributes must be refreshed */
  94         if (get_node_id(inode) == FUSE_ROOT_ID) {
  95                 err = fuse_do_getattr(inode);
  96                 if (err)
  97                         return err;
  98         }
  99
 100         ff = fuse_file_alloc();
 101         if (!ff)
 102                 return -ENOMEM;
 103
 104         err = fuse_send_open(inode, file, isdir, &outarg);
 105         if (err)
 106                 fuse_file_free(ff);
 107         else {
 108                 if (isdir)
 109                         outarg.open_flags &= ~FOPEN_DIRECT_IO;
 110                 fuse_finish_open(inode, file, ff, &outarg);
 111         }
 112
 113         return err;
 114 }
 115
 116 struct fuse_req *fuse_release_fill(struct fuse_file *ff, u64 nodeid, int flags,
 117                                    int opcode)
 118 {
 119         struct fuse_req *req = ff->reserved_req;
 120         struct fuse_release_in *inarg = &req->misc.release_in;
 121
 122         inarg->fh = ff->fh;
 123         inarg->flags = flags;
 124         req->in.h.opcode = opcode;
 125         req->in.h.nodeid = nodeid;
 126         req->in.numargs = 1;
 127         req->in.args[0].size = sizeof(struct fuse_release_in);
 128         req->in.args[0].value = inarg;
 129         kfree(ff);
 130
 131         return req;
 132 }
 133
 134 int fuse_release_common(struct inode *inode, struct file *file, int isdir)
 135 {
 136         struct fuse_file *ff = file->private_data;
 137         if (ff) {
 138                 struct fuse_conn *fc = get_fuse_conn(inode);
 139                 struct fuse_req *req;
 140
 141                 req = fuse_release_fill(ff, get_node_id(inode), file->f_flags,
 142                                         isdir ? FUSE_RELEASEDIR : FUSE_RELEASE);
 143
 144                 /* Hold vfsmount and dentry until release is finished */
 145                 req->vfsmount = mntget(file->f_path.mnt);
 146                 req->dentry = dget(file->f_path.dentry);
 147                 request_send_background(fc, req);
 148         }
 149
 150         /* Return value is ignored by VFS */
 151         return 0;
 152 }
 153
 154 static int fuse_open(struct inode *inode, struct file *file)
 155 {
 156         return fuse_open_common(inode, file, 0);
 157 }
 158
 159 static int fuse_release(struct inode *inode, struct file *file)
 160 {
 161         return fuse_release_common(inode, file, 0);
 162 }
 163
 164 /*
 165  * Scramble the ID space with XTEA, so that the value of the files_struct
 166  * pointer is not exposed to userspace.
 167  */
 168 static u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id)
 169 {
 170         u32 *k = fc->scramble_key;
 171         u64 v = (unsigned long) id;
 172         u32 v0 = v;
 173         u32 v1 = v >> 32;
 174         u32 sum = 0;
 175         int i;
 176
 177         for (i = 0; i < 32; i++) {
 178                 v0 += ((v1 << 4 ^ v1 >> 5) + v1) ^ (sum + k[sum & 3]);
 179                 sum += 0x9E3779B9;
 180                 v1 += ((v0 << 4 ^ v0 >> 5) + v0) ^ (sum + k[sum>>11 & 3]);
 181         }
 182
 183         return (u64) v0 + ((u64) v1 << 32);
 184 }
 185
 186 static int fuse_flush(struct file *file, fl_owner_t id)
 187 {
 188         struct inode *inode = file->f_path.dentry->d_inode;
 189         struct fuse_conn *fc = get_fuse_conn(inode);
 190         struct fuse_file *ff = file->private_data;
 191         struct fuse_req *req;
 192         struct fuse_flush_in inarg;
 193         int err;
 194
 195         if (is_bad_inode(inode))
 196                 return -EIO;
 197
 198         if (fc->no_flush)
 199                 return 0;
 200
 201         req = fuse_get_req_nofail(fc, file);
 202         memset(&inarg, 0, sizeof(inarg));
 203         inarg.fh = ff->fh;
 204         inarg.lock_owner = fuse_lock_owner_id(fc, id);
 205         req->in.h.opcode = FUSE_FLUSH;
 206         req->in.h.nodeid = get_node_id(inode);
 207         req->in.numargs = 1;
 208         req->in.args[0].size = sizeof(inarg);
 209         req->in.args[0].value = &inarg;
 210         req->force = 1;
 211         request_send(fc, req);
 212         err = req->out.h.error;
 213         fuse_put_request(fc, req);
 214         if (err == -ENOSYS) {
 215                 fc->no_flush = 1;
 216                 err = 0;
 217         }
 218         return err;
 219 }
 220
 221 int fuse_fsync_common(struct file *file, struct dentry *de, int datasync,
 222                       int isdir)
 223 {
 224         struct inode *inode = de->d_inode;
 225         struct fuse_conn *fc = get_fuse_conn(inode);
 226         struct fuse_file *ff = file->private_data;
 227         struct fuse_req *req;
 228         struct fuse_fsync_in inarg;
 229         int err;
 230
 231         if (is_bad_inode(inode))
 232                 return -EIO;
 233
 234         if ((!isdir && fc->no_fsync) || (isdir && fc->no_fsyncdir))
 235                 return 0;
 236
 237         req = fuse_get_req(fc);
 238         if (IS_ERR(req))
 239                 return PTR_ERR(req);
 240
 241         memset(&inarg, 0, sizeof(inarg));
 242         inarg.fh = ff->fh;
 243         inarg.fsync_flags = datasync ? 1 : 0;
 244         req->in.h.opcode = isdir ? FUSE_FSYNCDIR : FUSE_FSYNC;
 245         req->in.h.nodeid = get_node_id(inode);
 246         req->in.numargs = 1;
 247         req->in.args[0].size = sizeof(inarg);
 248         req->in.args[0].value = &inarg;
 249         request_send(fc, req);
 250         err = req->out.h.error;
 251         fuse_put_request(fc, req);
 252         if (err == -ENOSYS) {
 253                 if (isdir)
 254                         fc->no_fsyncdir = 1;
 255                 else
 256                         fc->no_fsync = 1;
 257                 err = 0;
 258         }
 259         return err;
 260 }
 261
 262 static int fuse_fsync(struct file *file, struct dentry *de, int datasync)
 263 {
 264         return fuse_fsync_common(file, de, datasync, 0);
 265 }
 266
 267 void fuse_read_fill(struct fuse_req *req, struct file *file,
 268                     struct inode *inode, loff_t pos, size_t count, int opcode)
 269 {
 270         struct fuse_file *ff = file->private_data;
 271         struct fuse_read_in *inarg = &req->misc.read_in;
 272
 273         inarg->fh = ff->fh;
 274         inarg->offset = pos;
 275         inarg->size = count;
 276         req->in.h.opcode = opcode;
 277         req->in.h.nodeid = get_node_id(inode);
 278         req->in.numargs = 1;
 279         req->in.args[0].size = sizeof(struct fuse_read_in);
 280         req->in.args[0].value = inarg;
 281         req->out.argpages = 1;
 282         req->out.argvar = 1;
 283         req->out.numargs = 1;
 284         req->out.args[0].size = count;
 285 }
 286
 287 static size_t fuse_send_read(struct fuse_req *req, struct file *file,
 288                              struct inode *inode, loff_t pos, size_t count)
 289 {
 290         struct fuse_conn *fc = get_fuse_conn(inode);
 291         fuse_read_fill(req, file, inode, pos, count, FUSE_READ);
 292         request_send(fc, req);
 293         return req->out.args[0].size;
 294 }
 295
 296 static int fuse_readpage(struct file *file, struct page *page)
 297 {
 298         struct inode *inode = page->mapping->host;
 299         struct fuse_conn *fc = get_fuse_conn(inode);
 300         struct fuse_req *req;
 301         int err;
 302
 303         err = -EIO;
 304         if (is_bad_inode(inode))
 305                 goto out;
 306
 307         req = fuse_get_req(fc);
 308         err = PTR_ERR(req);
 309         if (IS_ERR(req))
 310                 goto out;
 311
 312         req->out.page_zeroing = 1;
 313         req->num_pages = 1;
 314         req->pages[0] = page;
 315         fuse_send_read(req, file, inode, page_offset(page), PAGE_CACHE_SIZE);
 316         err = req->out.h.error;
 317         fuse_put_request(fc, req);
 318         if (!err)
 319                 SetPageUptodate(page);
 320         fuse_invalidate_attr(inode); /* atime changed */
 321  out:
 322         unlock_page(page);
 323         return err;
 324 }
 325
 326 static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req)
 327 {
 328         int i;
 329
 330         fuse_invalidate_attr(req->pages[0]->mapping->host); /* atime changed */
 331
 332         for (i = 0; i < req->num_pages; i++) {
 333                 struct page *page = req->pages[i];
 334                 if (!req->out.h.error)
 335                         SetPageUptodate(page);
 336                 else
 337                         SetPageError(page);
 338                 unlock_page(page);
 339         }
 340         fuse_put_request(fc, req);
 341 }
 342
 343 static void fuse_send_readpages(struct fuse_req *req, struct file *file,
 344                                 struct inode *inode)
 345 {
 346         struct fuse_conn *fc = get_fuse_conn(inode);
 347         loff_t pos = page_offset(req->pages[0]);
 348         size_t count = req->num_pages << PAGE_CACHE_SHIFT;
 349         req->out.page_zeroing = 1;
 350         fuse_read_fill(req, file, inode, pos, count, FUSE_READ);
 351         if (fc->async_read) {
 352                 get_file(file);
 353                 req->file = file;
 354                 req->end = fuse_readpages_end;
 355                 request_send_background(fc, req);
 356         } else {
 357                 request_send(fc, req);
 358                 fuse_readpages_end(fc, req);
 359         }
 360 }
 361
 362 struct fuse_readpages_data {
 363         struct fuse_req *req;
 364         struct file *file;
 365         struct inode *inode;
 366 };
 367
 368 static int fuse_readpages_fill(void *_data, struct page *page)
 369 {
 370         struct fuse_readpages_data *data = _data;
 371         struct fuse_req *req = data->req;
 372         struct inode *inode = data->inode;
 373         struct fuse_conn *fc = get_fuse_conn(inode);
 374
 375         if (req->num_pages &&
 376             (req->num_pages == FUSE_MAX_PAGES_PER_REQ ||
 377              (req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_read ||
 378              req->pages[req->num_pages - 1]->index + 1 != page->index)) {
 379                 fuse_send_readpages(req, data->file, inode);
 380                 data->req = req = fuse_get_req(fc);
 381                 if (IS_ERR(req)) {
 382                         unlock_page(page);
 383                         return PTR_ERR(req);
 384                 }
 385         }
 386         req->pages[req->num_pages] = page;
 387         req->num_pages ++;
 388         return 0;
 389 }
 390
 391 static int fuse_readpages(struct file *file, struct address_space *mapping,
 392                           struct list_head *pages, unsigned nr_pages)
 393 {
 394         struct inode *inode = mapping->host;
 395         struct fuse_conn *fc = get_fuse_conn(inode);
 396         struct fuse_readpages_data data;
 397         int err;
 398
 399         err = -EIO;
 400         if (is_bad_inode(inode))
 401                 goto out;
 402
 403         data.file = file;
 404         data.inode = inode;
 405         data.req = fuse_get_req(fc);
 406         err = PTR_ERR(data.req);
 407         if (IS_ERR(data.req))
 408                 goto out;
 409
 410         err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data);
 411         if (!err) {
 412                 if (data.req->num_pages)
 413                         fuse_send_readpages(data.req, file, inode);
 414                 else
 415                         fuse_put_request(fc, data.req);
 416         }
 417 out:
 418         return err;
 419 }
 420
 421 static size_t fuse_send_write(struct fuse_req *req, struct file *file,
 422                               struct inode *inode, loff_t pos, size_t count)
 423 {
 424         struct fuse_conn *fc = get_fuse_conn(inode);
 425         struct fuse_file *ff = file->private_data;
 426         struct fuse_write_in inarg;
 427         struct fuse_write_out outarg;
 428
 429         memset(&inarg, 0, sizeof(struct fuse_write_in));
 430         inarg.fh = ff->fh;
 431         inarg.offset = pos;
 432         inarg.size = count;
 433         req->in.h.opcode = FUSE_WRITE;
 434         req->in.h.nodeid = get_node_id(inode);
 435         req->in.argpages = 1;
 436         req->in.numargs = 2;
 437         req->in.args[0].size = sizeof(struct fuse_write_in);
 438         req->in.args[0].value = &inarg;
 439         req->in.args[1].size = count;
 440         req->out.numargs = 1;
 441         req->out.args[0].size = sizeof(struct fuse_write_out);
 442         req->out.args[0].value = &outarg;
 443         request_send(fc, req);
 444         return outarg.size;
 445 }
 446
 447 static int fuse_prepare_write(struct file *file, struct page *page,
 448                               unsigned offset, unsigned to)
 449 {
 450         /* No op */
 451         return 0;
 452 }
 453
 454 static int fuse_commit_write(struct file *file, struct page *page,
 455                              unsigned offset, unsigned to)
 456 {
 457         int err;
 458         size_t nres;
 459         unsigned count = to - offset;
 460         struct inode *inode = page->mapping->host;
 461         struct fuse_conn *fc = get_fuse_conn(inode);
 462         loff_t pos = page_offset(page) + offset;
 463         struct fuse_req *req;
 464
 465         if (is_bad_inode(inode))
 466                 return -EIO;
 467
 468         req = fuse_get_req(fc);
 469         if (IS_ERR(req))
 470                 return PTR_ERR(req);
 471
 472         req->num_pages = 1;
 473         req->pages[0] = page;
 474         req->page_offset = offset;
 475         nres = fuse_send_write(req, file, inode, pos, count);
 476         err = req->out.h.error;
 477         fuse_put_request(fc, req);
 478         if (!err && nres != count)
 479                 err = -EIO;
 480         if (!err) {
 481                 pos += count;
 482                 spin_lock(&fc->lock);
 483                 if (pos > inode->i_size)
 484                         i_size_write(inode, pos);
 485                 spin_unlock(&fc->lock);
 486
 487                 if (offset == 0 && to == PAGE_CACHE_SIZE)
 488                         SetPageUptodate(page);
 489         }
 490         fuse_invalidate_attr(inode);
 491         return err;
 492 }
 493
 494 static void fuse_release_user_pages(struct fuse_req *req, int write)
 495 {
 496         unsigned i;
 497
 498         for (i = 0; i < req->num_pages; i++) {
 499                 struct page *page = req->pages[i];
 500                 if (write)
 501                         set_page_dirty_lock(page);
 502                 put_page(page);
 503         }
 504 }
 505
 506 static int fuse_get_user_pages(struct fuse_req *req, const char __user *buf,
 507                                unsigned nbytes, int write)
 508 {
 509         unsigned long user_addr = (unsigned long) buf;
 510         unsigned offset = user_addr & ~PAGE_MASK;
 511         int npages;
 512
 513         /* This doesn't work with nfsd */
 514         if (!current->mm)
 515                 return -EPERM;
 516
 517         nbytes = min(nbytes, (unsigned) FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT);
 518         npages = (nbytes + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
 519         npages = min(max(npages, 1), FUSE_MAX_PAGES_PER_REQ);
 520         down_read(&current->mm->mmap_sem);
 521         npages = get_user_pages(current, current->mm, user_addr, npages, write,
 522                                 0, req->pages, NULL);
 523         up_read(&current->mm->mmap_sem);
 524         if (npages < 0)
 525                 return npages;
 526
 527         req->num_pages = npages;
 528         req->page_offset = offset;
 529         return 0;
 530 }
 531
 532 static ssize_t fuse_direct_io(struct file *file, const char __user *buf,
 533                               size_t count, loff_t *ppos, int write)
 534 {
 535         struct inode *inode = file->f_path.dentry->d_inode;
 536         struct fuse_conn *fc = get_fuse_conn(inode);
 537         size_t nmax = write ? fc->max_write : fc->max_read;
 538         loff_t pos = *ppos;
 539         ssize_t res = 0;
 540         struct fuse_req *req;
 541
 542         if (is_bad_inode(inode))
 543                 return -EIO;
 544
 545         req = fuse_get_req(fc);
 546         if (IS_ERR(req))
 547                 return PTR_ERR(req);
 548
 549         while (count) {
 550                 size_t nres;
 551                 size_t nbytes = min(count, nmax);
 552                 int err = fuse_get_user_pages(req, buf, nbytes, !write);
 553                 if (err) {
 554                         res = err;
 555                         break;
 556                 }
 557                 nbytes = (req->num_pages << PAGE_SHIFT) - req->page_offset;
 558                 nbytes = min(count, nbytes);
 559                 if (write)
 560                         nres = fuse_send_write(req, file, inode, pos, nbytes);
 561                 else
 562                         nres = fuse_send_read(req, file, inode, pos, nbytes);
 563                 fuse_release_user_pages(req, !write);
 564                 if (req->out.h.error) {
 565                         if (!res)
 566                                 res = req->out.h.error;
 567                         break;
 568                 } else if (nres > nbytes) {
 569                         res = -EIO;
 570                         break;
 571                 }
 572                 count -= nres;
 573                 res += nres;
 574                 pos += nres;
 575                 buf += nres;
 576                 if (nres != nbytes)
 577                         break;
 578                 if (count) {
 579                         fuse_put_request(fc, req);
 580                         req = fuse_get_req(fc);
 581                         if (IS_ERR(req))
 582                                 break;
 583                 }
 584         }
 585         fuse_put_request(fc, req);
 586         if (res > 0) {
 587                 if (write) {
 588                         spin_lock(&fc->lock);
 589                         if (pos > inode->i_size)
 590                                 i_size_write(inode, pos);
 591                         spin_unlock(&fc->lock);
 592                 }
 593                 *ppos = pos;
 594         }
 595         fuse_invalidate_attr(inode);
 596
 597         return res;
 598 }
 599
 600 static ssize_t fuse_direct_read(struct file *file, char __user *buf,
 601                                      size_t count, loff_t *ppos)
 602 {
 603         return fuse_direct_io(file, buf, count, ppos, 0);
 604 }
 605
 606 static ssize_t fuse_direct_write(struct file *file, const char __user *buf,
 607                                  size_t count, loff_t *ppos)
 608 {
 609         struct inode *inode = file->f_path.dentry->d_inode;
 610         ssize_t res;
 611         /* Don't allow parallel writes to the same file */
 612         mutex_lock(&inode->i_mutex);
 613         res = generic_write_checks(file, ppos, &count, 0);
 614         if (!res)
 615                 res = fuse_direct_io(file, buf, count, ppos, 1);
 616         mutex_unlock(&inode->i_mutex);
 617         return res;
 618 }
 619
 620 static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma)
 621 {
 622         if ((vma->vm_flags & VM_SHARED)) {
 623                 if ((vma->vm_flags & VM_WRITE))
 624                         return -ENODEV;
 625                 else
 626                         vma->vm_flags &= ~VM_MAYWRITE;
 627         }
 628         return generic_file_mmap(file, vma);
 629 }
 630
 631 static int fuse_set_page_dirty(struct page *page)
 632 {
 633         printk("fuse_set_page_dirty: should not happen\n");
 634         dump_stack();
 635         return 0;
 636 }
 637
 638 static int convert_fuse_file_lock(const struct fuse_file_lock *ffl,
 639                                   struct file_lock *fl)
 640 {
 641         switch (ffl->type) {
 642         case F_UNLCK:
 643                 break;
 644
 645         case F_RDLCK:
 646         case F_WRLCK:
 647                 if (ffl->start > OFFSET_MAX || ffl->end > OFFSET_MAX ||
 648                     ffl->end < ffl->start)
 649                         return -EIO;
 650
 651                 fl->fl_start = ffl->start;
 652                 fl->fl_end = ffl->end;
 653                 fl->fl_pid = ffl->pid;
 654                 break;
 655
 656         default:
 657                 return -EIO;
 658         }
 659         fl->fl_type = ffl->type;
 660         return 0;
 661 }
 662
 663 static void fuse_lk_fill(struct fuse_req *req, struct file *file,
 664                          const struct file_lock *fl, int opcode, pid_t pid)
 665 {
 666         struct inode *inode = file->f_path.dentry->d_inode;
 667         struct fuse_conn *fc = get_fuse_conn(inode);
 668         struct fuse_file *ff = file->private_data;
 669         struct fuse_lk_in *arg = &req->misc.lk_in;
 670
 671         arg->fh = ff->fh;
 672         arg->owner = fuse_lock_owner_id(fc, fl->fl_owner);
 673         arg->lk.start = fl->fl_start;
 674         arg->lk.end = fl->fl_end;
 675         arg->lk.type = fl->fl_type;
 676         arg->lk.pid = pid;
 677         req->in.h.opcode = opcode;
 678         req->in.h.nodeid = get_node_id(inode);
 679         req->in.numargs = 1;
 680         req->in.args[0].size = sizeof(*arg);
 681         req->in.args[0].value = arg;
 682 }
 683
 684 static int fuse_getlk(struct file *file, struct file_lock *fl)
 685 {
 686         struct inode *inode = file->f_path.dentry->d_inode;
 687         struct fuse_conn *fc = get_fuse_conn(inode);
 688         struct fuse_req *req;
 689         struct fuse_lk_out outarg;
 690         int err;
 691
 692         req = fuse_get_req(fc);
 693         if (IS_ERR(req))
 694                 return PTR_ERR(req);
 695
 696         fuse_lk_fill(req, file, fl, FUSE_GETLK, 0);
 697         req->out.numargs = 1;
 698         req->out.args[0].size = sizeof(outarg);
 699         req->out.args[0].value = &outarg;
 700         request_send(fc, req);
 701         err = req->out.h.error;
 702         fuse_put_request(fc, req);
 703         if (!err)
 704                 err = convert_fuse_file_lock(&outarg.lk, fl);
 705
 706         return err;
 707 }
 708
 709 static int fuse_setlk(struct file *file, struct file_lock *fl)
 710 {
 711         struct inode *inode = file->f_path.dentry->d_inode;
 712         struct fuse_conn *fc = get_fuse_conn(inode);
 713         struct fuse_req *req;
 714         int opcode = (fl->fl_flags & FL_SLEEP) ? FUSE_SETLKW : FUSE_SETLK;
 715         pid_t pid = fl->fl_type != F_UNLCK ? current->tgid : 0;
 716         int err;
 717
 718         /* Unlock on close is handled by the flush method */
 719         if (fl->fl_flags & FL_CLOSE)
 720                 return 0;
 721
 722         req = fuse_get_req(fc);
 723         if (IS_ERR(req))
 724                 return PTR_ERR(req);
 725
 726         fuse_lk_fill(req, file, fl, opcode, pid);
 727         request_send(fc, req);
 728         err = req->out.h.error;
 729         /* locking is restartable */
 730         if (err == -EINTR)
 731                 err = -ERESTARTSYS;
 732         fuse_put_request(fc, req);
 733         return err;
 734 }
 735
 736 static int fuse_file_lock(struct file *file, int cmd, struct file_lock *fl)
 737 {
 738         struct inode *inode = file->f_path.dentry->d_inode;
 739         struct fuse_conn *fc = get_fuse_conn(inode);
 740         int err;
 741
 742         if (cmd == F_GETLK) {
 743                 if (fc->no_lock) {
 744                         posix_test_lock(file, fl);
 745                         err = 0;
 746                 } else
 747                         err = fuse_getlk(file, fl);
 748         } else {
 749                 if (fc->no_lock)
 750                         err = posix_lock_file_wait(file, fl);
 751                 else
 752                         err = fuse_setlk(file, fl);
 753         }
 754         return err;
 755 }
 756
 757 static sector_t fuse_bmap(struct address_space *mapping, sector_t block)
 758 {
 759         struct inode *inode = mapping->host;
 760         struct fuse_conn *fc = get_fuse_conn(inode);
 761         struct fuse_req *req;
 762         struct fuse_bmap_in inarg;
 763         struct fuse_bmap_out outarg;
 764         int err;
 765
 766         if (!inode->i_sb->s_bdev || fc->no_bmap)
 767                 return 0;
 768
 769         req = fuse_get_req(fc);
 770         if (IS_ERR(req))
 771                 return 0;
 772
 773         memset(&inarg, 0, sizeof(inarg));
 774         inarg.block = block;
 775         inarg.blocksize = inode->i_sb->s_blocksize;
 776         req->in.h.opcode = FUSE_BMAP;
 777         req->in.h.nodeid = get_node_id(inode);
 778         req->in.numargs = 1;
 779         req->in.args[0].size = sizeof(inarg);
 780         req->in.args[0].value = &inarg;
 781         req->out.numargs = 1;
 782         req->out.args[0].size = sizeof(outarg);
 783         req->out.args[0].value = &outarg;
 784         request_send(fc, req);
 785         err = req->out.h.error;
 786         fuse_put_request(fc, req);
 787         if (err == -ENOSYS)
 788                 fc->no_bmap = 1;
 789
 790         return err ? 0 : outarg.block;
 791 }
 792
 793 static const struct file_operations fuse_file_operations = {
 794         .llseek         = generic_file_llseek,
 795         .read           = do_sync_read,
 796         .aio_read       = generic_file_aio_read,
 797         .write          = do_sync_write,
 798         .aio_write      = generic_file_aio_write,
 799         .mmap           = fuse_file_mmap,
 800         .open           = fuse_open,
 801         .flush          = fuse_flush,
 802         .release        = fuse_release,
 803         .fsync          = fuse_fsync,
 804         .lock           = fuse_file_lock,
 805         .splice_read    = generic_file_splice_read,
 806 };
 807
 808 static const struct file_operations fuse_direct_io_file_operations = {
 809         .llseek         = generic_file_llseek,
 810         .read           = fuse_direct_read,
 811         .write          = fuse_direct_write,
 812         .open           = fuse_open,
 813         .flush          = fuse_flush,
 814         .release        = fuse_release,
 815         .fsync          = fuse_fsync,
 816         .lock           = fuse_file_lock,
 817         /* no mmap and splice_read */
 818 };
 819
 820 static const struct address_space_operations fuse_file_aops  = {
 821         .readpage       = fuse_readpage,
 822         .prepare_write  = fuse_prepare_write,
 823         .commit_write   = fuse_commit_write,
 824         .readpages      = fuse_readpages,
 825         .set_page_dirty = fuse_set_page_dirty,
 826         .bmap           = fuse_bmap,
 827 };
 828
 829 void fuse_init_file_inode(struct inode *inode)
 830 {
 831         inode->i_fop = &fuse_file_operations;
 832         inode->i_data.a_ops = &fuse_file_aops;
 833 }