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