1 #include <linux/ceph/ceph_debug.h> 2 3 #include <linux/module.h> 4 #include <linux/sched.h> 5 #include <linux/slab.h> 6 #include <linux/file.h> 7 #include <linux/namei.h> 8 #include <linux/writeback.h> 9 10 #include "super.h" 11 #include "mds_client.h" 12 13 /* 14 * Ceph file operations 15 * 16 * Implement basic open/close functionality, and implement 17 * read/write. 18 * 19 * We implement three modes of file I/O: 20 * - buffered uses the generic_file_aio_{read,write} helpers 21 * 22 * - synchronous is used when there is multi-client read/write 23 * sharing, avoids the page cache, and synchronously waits for an 24 * ack from the OSD. 25 * 26 * - direct io takes the variant of the sync path that references 27 * user pages directly. 28 * 29 * fsync() flushes and waits on dirty pages, but just queues metadata 30 * for writeback: since the MDS can recover size and mtime there is no 31 * need to wait for MDS acknowledgement. 32 */ 33 34 35 /* 36 * Prepare an open request. Preallocate ceph_cap to avoid an 37 * inopportune ENOMEM later. 38 */ 39 static struct ceph_mds_request * 40 prepare_open_request(struct super_block *sb, int flags, int create_mode) 41 { 42 struct ceph_fs_client *fsc = ceph_sb_to_client(sb); 43 struct ceph_mds_client *mdsc = fsc->mdsc; 44 struct ceph_mds_request *req; 45 int want_auth = USE_ANY_MDS; 46 int op = (flags & O_CREAT) ? CEPH_MDS_OP_CREATE : CEPH_MDS_OP_OPEN; 47 48 if (flags & (O_WRONLY|O_RDWR|O_CREAT|O_TRUNC)) 49 want_auth = USE_AUTH_MDS; 50 51 req = ceph_mdsc_create_request(mdsc, op, want_auth); 52 if (IS_ERR(req)) 53 goto out; 54 req->r_fmode = ceph_flags_to_mode(flags); 55 req->r_args.open.flags = cpu_to_le32(flags); 56 req->r_args.open.mode = cpu_to_le32(create_mode); 57 req->r_args.open.preferred = cpu_to_le32(-1); 58 out: 59 return req; 60 } 61 62 /* 63 * initialize private struct file data. 64 * if we fail, clean up by dropping fmode reference on the ceph_inode 65 */ 66 static int ceph_init_file(struct inode *inode, struct file *file, int fmode) 67 { 68 struct ceph_file_info *cf; 69 int ret = 0; 70 71 switch (inode->i_mode & S_IFMT) { 72 case S_IFREG: 73 case S_IFDIR: 74 dout("init_file %p %p 0%o (regular)\n", inode, file, 75 inode->i_mode); 76 cf = kmem_cache_alloc(ceph_file_cachep, GFP_NOFS | __GFP_ZERO); 77 if (cf == NULL) { 78 ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */ 79 return -ENOMEM; 80 } 81 cf->fmode = fmode; 82 cf->next_offset = 2; 83 file->private_data = cf; 84 BUG_ON(inode->i_fop->release != ceph_release); 85 break; 86 87 case S_IFLNK: 88 dout("init_file %p %p 0%o (symlink)\n", inode, file, 89 inode->i_mode); 90 ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */ 91 break; 92 93 default: 94 dout("init_file %p %p 0%o (special)\n", inode, file, 95 inode->i_mode); 96 /* 97 * we need to drop the open ref now, since we don't 98 * have .release set to ceph_release. 99 */ 100 ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */ 101 BUG_ON(inode->i_fop->release == ceph_release); 102 103 /* call the proper open fop */ 104 ret = inode->i_fop->open(inode, file); 105 } 106 return ret; 107 } 108 109 /* 110 * If the filp already has private_data, that means the file was 111 * already opened by intent during lookup, and we do nothing. 112 * 113 * If we already have the requisite capabilities, we can satisfy 114 * the open request locally (no need to request new caps from the 115 * MDS). We do, however, need to inform the MDS (asynchronously) 116 * if our wanted caps set expands. 117 */ 118 int ceph_open(struct inode *inode, struct file *file) 119 { 120 struct ceph_inode_info *ci = ceph_inode(inode); 121 struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb); 122 struct ceph_mds_client *mdsc = fsc->mdsc; 123 struct ceph_mds_request *req; 124 struct ceph_file_info *cf = file->private_data; 125 struct inode *parent_inode = file->f_dentry->d_parent->d_inode; 126 int err; 127 int flags, fmode, wanted; 128 129 if (cf) { 130 dout("open file %p is already opened\n", file); 131 return 0; 132 } 133 134 /* filter out O_CREAT|O_EXCL; vfs did that already. yuck. */ 135 flags = file->f_flags & ~(O_CREAT|O_EXCL); 136 if (S_ISDIR(inode->i_mode)) 137 flags = O_DIRECTORY; /* mds likes to know */ 138 139 dout("open inode %p ino %llx.%llx file %p flags %d (%d)\n", inode, 140 ceph_vinop(inode), file, flags, file->f_flags); 141 fmode = ceph_flags_to_mode(flags); 142 wanted = ceph_caps_for_mode(fmode); 143 144 /* snapped files are read-only */ 145 if (ceph_snap(inode) != CEPH_NOSNAP && (file->f_mode & FMODE_WRITE)) 146 return -EROFS; 147 148 /* trivially open snapdir */ 149 if (ceph_snap(inode) == CEPH_SNAPDIR) { 150 spin_lock(&inode->i_lock); 151 __ceph_get_fmode(ci, fmode); 152 spin_unlock(&inode->i_lock); 153 return ceph_init_file(inode, file, fmode); 154 } 155 156 /* 157 * No need to block if we have caps on the auth MDS (for 158 * write) or any MDS (for read). Update wanted set 159 * asynchronously. 160 */ 161 spin_lock(&inode->i_lock); 162 if (__ceph_is_any_real_caps(ci) && 163 (((fmode & CEPH_FILE_MODE_WR) == 0) || ci->i_auth_cap)) { 164 int mds_wanted = __ceph_caps_mds_wanted(ci); 165 int issued = __ceph_caps_issued(ci, NULL); 166 167 dout("open %p fmode %d want %s issued %s using existing\n", 168 inode, fmode, ceph_cap_string(wanted), 169 ceph_cap_string(issued)); 170 __ceph_get_fmode(ci, fmode); 171 spin_unlock(&inode->i_lock); 172 173 /* adjust wanted? */ 174 if ((issued & wanted) != wanted && 175 (mds_wanted & wanted) != wanted && 176 ceph_snap(inode) != CEPH_SNAPDIR) 177 ceph_check_caps(ci, 0, NULL); 178 179 return ceph_init_file(inode, file, fmode); 180 } else if (ceph_snap(inode) != CEPH_NOSNAP && 181 (ci->i_snap_caps & wanted) == wanted) { 182 __ceph_get_fmode(ci, fmode); 183 spin_unlock(&inode->i_lock); 184 return ceph_init_file(inode, file, fmode); 185 } 186 spin_unlock(&inode->i_lock); 187 188 dout("open fmode %d wants %s\n", fmode, ceph_cap_string(wanted)); 189 req = prepare_open_request(inode->i_sb, flags, 0); 190 if (IS_ERR(req)) { 191 err = PTR_ERR(req); 192 goto out; 193 } 194 req->r_inode = inode; 195 ihold(inode); 196 req->r_num_caps = 1; 197 err = ceph_mdsc_do_request(mdsc, parent_inode, req); 198 if (!err) 199 err = ceph_init_file(inode, file, req->r_fmode); 200 ceph_mdsc_put_request(req); 201 dout("open result=%d on %llx.%llx\n", err, ceph_vinop(inode)); 202 out: 203 return err; 204 } 205 206 207 /* 208 * Do a lookup + open with a single request. 209 * 210 * If this succeeds, but some subsequent check in the vfs 211 * may_open() fails, the struct *file gets cleaned up (i.e. 212 * ceph_release gets called). So fear not! 213 */ 214 /* 215 * flags 216 * path_lookup_open -> LOOKUP_OPEN 217 * path_lookup_create -> LOOKUP_OPEN|LOOKUP_CREATE 218 */ 219 struct dentry *ceph_lookup_open(struct inode *dir, struct dentry *dentry, 220 struct nameidata *nd, int mode, 221 int locked_dir) 222 { 223 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb); 224 struct ceph_mds_client *mdsc = fsc->mdsc; 225 struct file *file = nd->intent.open.file; 226 struct inode *parent_inode = get_dentry_parent_inode(file->f_dentry); 227 struct ceph_mds_request *req; 228 int err; 229 int flags = nd->intent.open.flags - 1; /* silly vfs! */ 230 231 dout("ceph_lookup_open dentry %p '%.*s' flags %d mode 0%o\n", 232 dentry, dentry->d_name.len, dentry->d_name.name, flags, mode); 233 234 /* do the open */ 235 req = prepare_open_request(dir->i_sb, flags, mode); 236 if (IS_ERR(req)) 237 return ERR_CAST(req); 238 req->r_dentry = dget(dentry); 239 req->r_num_caps = 2; 240 if (flags & O_CREAT) { 241 req->r_dentry_drop = CEPH_CAP_FILE_SHARED; 242 req->r_dentry_unless = CEPH_CAP_FILE_EXCL; 243 } 244 req->r_locked_dir = dir; /* caller holds dir->i_mutex */ 245 err = ceph_mdsc_do_request(mdsc, parent_inode, req); 246 dentry = ceph_finish_lookup(req, dentry, err); 247 if (!err && (flags & O_CREAT) && !req->r_reply_info.head->is_dentry) 248 err = ceph_handle_notrace_create(dir, dentry); 249 if (!err) 250 err = ceph_init_file(req->r_dentry->d_inode, file, 251 req->r_fmode); 252 ceph_mdsc_put_request(req); 253 dout("ceph_lookup_open result=%p\n", dentry); 254 return dentry; 255 } 256 257 int ceph_release(struct inode *inode, struct file *file) 258 { 259 struct ceph_inode_info *ci = ceph_inode(inode); 260 struct ceph_file_info *cf = file->private_data; 261 262 dout("release inode %p file %p\n", inode, file); 263 ceph_put_fmode(ci, cf->fmode); 264 if (cf->last_readdir) 265 ceph_mdsc_put_request(cf->last_readdir); 266 kfree(cf->last_name); 267 kfree(cf->dir_info); 268 dput(cf->dentry); 269 kmem_cache_free(ceph_file_cachep, cf); 270 271 /* wake up anyone waiting for caps on this inode */ 272 wake_up_all(&ci->i_cap_wq); 273 return 0; 274 } 275 276 /* 277 * Read a range of bytes striped over one or more objects. Iterate over 278 * objects we stripe over. (That's not atomic, but good enough for now.) 279 * 280 * If we get a short result from the OSD, check against i_size; we need to 281 * only return a short read to the caller if we hit EOF. 282 */ 283 static int striped_read(struct inode *inode, 284 u64 off, u64 len, 285 struct page **pages, int num_pages, 286 int *checkeof, bool o_direct, 287 unsigned long buf_align) 288 { 289 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 290 struct ceph_inode_info *ci = ceph_inode(inode); 291 u64 pos, this_len; 292 int io_align, page_align; 293 int left, pages_left; 294 int read; 295 struct page **page_pos; 296 int ret; 297 bool hit_stripe, was_short; 298 299 /* 300 * we may need to do multiple reads. not atomic, unfortunately. 301 */ 302 pos = off; 303 left = len; 304 page_pos = pages; 305 pages_left = num_pages; 306 read = 0; 307 io_align = off & ~PAGE_MASK; 308 309 more: 310 if (o_direct) 311 page_align = (pos - io_align + buf_align) & ~PAGE_MASK; 312 else 313 page_align = pos & ~PAGE_MASK; 314 this_len = left; 315 ret = ceph_osdc_readpages(&fsc->client->osdc, ceph_vino(inode), 316 &ci->i_layout, pos, &this_len, 317 ci->i_truncate_seq, 318 ci->i_truncate_size, 319 page_pos, pages_left, page_align); 320 if (ret == -ENOENT) 321 ret = 0; 322 hit_stripe = this_len < left; 323 was_short = ret >= 0 && ret < this_len; 324 dout("striped_read %llu~%u (read %u) got %d%s%s\n", pos, left, read, 325 ret, hit_stripe ? " HITSTRIPE" : "", was_short ? " SHORT" : ""); 326 327 if (ret > 0) { 328 int didpages = (page_align + ret) >> PAGE_CACHE_SHIFT; 329 330 if (read < pos - off) { 331 dout(" zero gap %llu to %llu\n", off + read, pos); 332 ceph_zero_page_vector_range(page_align + read, 333 pos - off - read, pages); 334 } 335 pos += ret; 336 read = pos - off; 337 left -= ret; 338 page_pos += didpages; 339 pages_left -= didpages; 340 341 /* hit stripe? */ 342 if (left && hit_stripe) 343 goto more; 344 } 345 346 if (was_short) { 347 /* did we bounce off eof? */ 348 if (pos + left > inode->i_size) 349 *checkeof = 1; 350 351 /* zero trailing bytes (inside i_size) */ 352 if (left > 0 && pos < inode->i_size) { 353 if (pos + left > inode->i_size) 354 left = inode->i_size - pos; 355 356 dout("zero tail %d\n", left); 357 ceph_zero_page_vector_range(page_align + read, left, 358 pages); 359 read += left; 360 } 361 } 362 363 if (ret >= 0) 364 ret = read; 365 dout("striped_read returns %d\n", ret); 366 return ret; 367 } 368 369 /* 370 * Completely synchronous read and write methods. Direct from __user 371 * buffer to osd, or directly to user pages (if O_DIRECT). 372 * 373 * If the read spans object boundary, just do multiple reads. 374 */ 375 static ssize_t ceph_sync_read(struct file *file, char __user *data, 376 unsigned len, loff_t *poff, int *checkeof) 377 { 378 struct inode *inode = file->f_dentry->d_inode; 379 struct page **pages; 380 u64 off = *poff; 381 int num_pages, ret; 382 383 dout("sync_read on file %p %llu~%u %s\n", file, off, len, 384 (file->f_flags & O_DIRECT) ? "O_DIRECT" : ""); 385 386 if (file->f_flags & O_DIRECT) { 387 num_pages = calc_pages_for((unsigned long)data, len); 388 pages = ceph_get_direct_page_vector(data, num_pages, true); 389 } else { 390 num_pages = calc_pages_for(off, len); 391 pages = ceph_alloc_page_vector(num_pages, GFP_NOFS); 392 } 393 if (IS_ERR(pages)) 394 return PTR_ERR(pages); 395 396 /* 397 * flush any page cache pages in this range. this 398 * will make concurrent normal and sync io slow, 399 * but it will at least behave sensibly when they are 400 * in sequence. 401 */ 402 ret = filemap_write_and_wait(inode->i_mapping); 403 if (ret < 0) 404 goto done; 405 406 ret = striped_read(inode, off, len, pages, num_pages, checkeof, 407 file->f_flags & O_DIRECT, 408 (unsigned long)data & ~PAGE_MASK); 409 410 if (ret >= 0 && (file->f_flags & O_DIRECT) == 0) 411 ret = ceph_copy_page_vector_to_user(pages, data, off, ret); 412 if (ret >= 0) 413 *poff = off + ret; 414 415 done: 416 if (file->f_flags & O_DIRECT) 417 ceph_put_page_vector(pages, num_pages, true); 418 else 419 ceph_release_page_vector(pages, num_pages); 420 dout("sync_read result %d\n", ret); 421 return ret; 422 } 423 424 /* 425 * Write commit callback, called if we requested both an ACK and 426 * ONDISK commit reply from the OSD. 427 */ 428 static void sync_write_commit(struct ceph_osd_request *req, 429 struct ceph_msg *msg) 430 { 431 struct ceph_inode_info *ci = ceph_inode(req->r_inode); 432 433 dout("sync_write_commit %p tid %llu\n", req, req->r_tid); 434 spin_lock(&ci->i_unsafe_lock); 435 list_del_init(&req->r_unsafe_item); 436 spin_unlock(&ci->i_unsafe_lock); 437 ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR); 438 } 439 440 /* 441 * Synchronous write, straight from __user pointer or user pages (if 442 * O_DIRECT). 443 * 444 * If write spans object boundary, just do multiple writes. (For a 445 * correct atomic write, we should e.g. take write locks on all 446 * objects, rollback on failure, etc.) 447 */ 448 static ssize_t ceph_sync_write(struct file *file, const char __user *data, 449 size_t left, loff_t *offset) 450 { 451 struct inode *inode = file->f_dentry->d_inode; 452 struct ceph_inode_info *ci = ceph_inode(inode); 453 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 454 struct ceph_osd_request *req; 455 struct page **pages; 456 int num_pages; 457 long long unsigned pos; 458 u64 len; 459 int written = 0; 460 int flags; 461 int do_sync = 0; 462 int check_caps = 0; 463 int page_align, io_align; 464 unsigned long buf_align; 465 int ret; 466 struct timespec mtime = CURRENT_TIME; 467 468 if (ceph_snap(file->f_dentry->d_inode) != CEPH_NOSNAP) 469 return -EROFS; 470 471 dout("sync_write on file %p %lld~%u %s\n", file, *offset, 472 (unsigned)left, (file->f_flags & O_DIRECT) ? "O_DIRECT" : ""); 473 474 if (file->f_flags & O_APPEND) 475 pos = i_size_read(inode); 476 else 477 pos = *offset; 478 479 ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + left); 480 if (ret < 0) 481 return ret; 482 483 ret = invalidate_inode_pages2_range(inode->i_mapping, 484 pos >> PAGE_CACHE_SHIFT, 485 (pos + left) >> PAGE_CACHE_SHIFT); 486 if (ret < 0) 487 dout("invalidate_inode_pages2_range returned %d\n", ret); 488 489 flags = CEPH_OSD_FLAG_ORDERSNAP | 490 CEPH_OSD_FLAG_ONDISK | 491 CEPH_OSD_FLAG_WRITE; 492 if ((file->f_flags & (O_SYNC|O_DIRECT)) == 0) 493 flags |= CEPH_OSD_FLAG_ACK; 494 else 495 do_sync = 1; 496 497 /* 498 * we may need to do multiple writes here if we span an object 499 * boundary. this isn't atomic, unfortunately. :( 500 */ 501 more: 502 io_align = pos & ~PAGE_MASK; 503 buf_align = (unsigned long)data & ~PAGE_MASK; 504 len = left; 505 if (file->f_flags & O_DIRECT) { 506 /* write from beginning of first page, regardless of 507 io alignment */ 508 page_align = (pos - io_align + buf_align) & ~PAGE_MASK; 509 num_pages = calc_pages_for((unsigned long)data, len); 510 } else { 511 page_align = pos & ~PAGE_MASK; 512 num_pages = calc_pages_for(pos, len); 513 } 514 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout, 515 ceph_vino(inode), pos, &len, 516 CEPH_OSD_OP_WRITE, flags, 517 ci->i_snap_realm->cached_context, 518 do_sync, 519 ci->i_truncate_seq, ci->i_truncate_size, 520 &mtime, false, 2, page_align); 521 if (!req) 522 return -ENOMEM; 523 524 if (file->f_flags & O_DIRECT) { 525 pages = ceph_get_direct_page_vector(data, num_pages, false); 526 if (IS_ERR(pages)) { 527 ret = PTR_ERR(pages); 528 goto out; 529 } 530 531 /* 532 * throw out any page cache pages in this range. this 533 * may block. 534 */ 535 truncate_inode_pages_range(inode->i_mapping, pos, 536 (pos+len) | (PAGE_CACHE_SIZE-1)); 537 } else { 538 pages = ceph_alloc_page_vector(num_pages, GFP_NOFS); 539 if (IS_ERR(pages)) { 540 ret = PTR_ERR(pages); 541 goto out; 542 } 543 ret = ceph_copy_user_to_page_vector(pages, data, pos, len); 544 if (ret < 0) { 545 ceph_release_page_vector(pages, num_pages); 546 goto out; 547 } 548 549 if ((file->f_flags & O_SYNC) == 0) { 550 /* get a second commit callback */ 551 req->r_safe_callback = sync_write_commit; 552 req->r_own_pages = 1; 553 } 554 } 555 req->r_pages = pages; 556 req->r_num_pages = num_pages; 557 req->r_inode = inode; 558 559 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false); 560 if (!ret) { 561 if (req->r_safe_callback) { 562 /* 563 * Add to inode unsafe list only after we 564 * start_request so that a tid has been assigned. 565 */ 566 spin_lock(&ci->i_unsafe_lock); 567 list_add_tail(&req->r_unsafe_item, 568 &ci->i_unsafe_writes); 569 spin_unlock(&ci->i_unsafe_lock); 570 ceph_get_cap_refs(ci, CEPH_CAP_FILE_WR); 571 } 572 573 ret = ceph_osdc_wait_request(&fsc->client->osdc, req); 574 if (ret < 0 && req->r_safe_callback) { 575 spin_lock(&ci->i_unsafe_lock); 576 list_del_init(&req->r_unsafe_item); 577 spin_unlock(&ci->i_unsafe_lock); 578 ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR); 579 } 580 } 581 582 if (file->f_flags & O_DIRECT) 583 ceph_put_page_vector(pages, num_pages, false); 584 else if (file->f_flags & O_SYNC) 585 ceph_release_page_vector(pages, num_pages); 586 587 out: 588 ceph_osdc_put_request(req); 589 if (ret == 0) { 590 pos += len; 591 written += len; 592 left -= len; 593 data += written; 594 if (left) 595 goto more; 596 597 ret = written; 598 *offset = pos; 599 if (pos > i_size_read(inode)) 600 check_caps = ceph_inode_set_size(inode, pos); 601 if (check_caps) 602 ceph_check_caps(ceph_inode(inode), CHECK_CAPS_AUTHONLY, 603 NULL); 604 } 605 return ret; 606 } 607 608 /* 609 * Wrap generic_file_aio_read with checks for cap bits on the inode. 610 * Atomically grab references, so that those bits are not released 611 * back to the MDS mid-read. 612 * 613 * Hmm, the sync read case isn't actually async... should it be? 614 */ 615 static ssize_t ceph_aio_read(struct kiocb *iocb, const struct iovec *iov, 616 unsigned long nr_segs, loff_t pos) 617 { 618 struct file *filp = iocb->ki_filp; 619 struct ceph_file_info *fi = filp->private_data; 620 loff_t *ppos = &iocb->ki_pos; 621 size_t len = iov->iov_len; 622 struct inode *inode = filp->f_dentry->d_inode; 623 struct ceph_inode_info *ci = ceph_inode(inode); 624 void __user *base = iov->iov_base; 625 ssize_t ret; 626 int want, got = 0; 627 int checkeof = 0, read = 0; 628 629 dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n", 630 inode, ceph_vinop(inode), pos, (unsigned)len, inode); 631 again: 632 __ceph_do_pending_vmtruncate(inode); 633 if (fi->fmode & CEPH_FILE_MODE_LAZY) 634 want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO; 635 else 636 want = CEPH_CAP_FILE_CACHE; 637 ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, &got, -1); 638 if (ret < 0) 639 goto out; 640 dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n", 641 inode, ceph_vinop(inode), pos, (unsigned)len, 642 ceph_cap_string(got)); 643 644 if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 || 645 (iocb->ki_filp->f_flags & O_DIRECT) || 646 (inode->i_sb->s_flags & MS_SYNCHRONOUS)) 647 /* hmm, this isn't really async... */ 648 ret = ceph_sync_read(filp, base, len, ppos, &checkeof); 649 else 650 ret = generic_file_aio_read(iocb, iov, nr_segs, pos); 651 652 out: 653 dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n", 654 inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret); 655 ceph_put_cap_refs(ci, got); 656 657 if (checkeof && ret >= 0) { 658 int statret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE); 659 660 /* hit EOF or hole? */ 661 if (statret == 0 && *ppos < inode->i_size) { 662 dout("aio_read sync_read hit hole, ppos %lld < size %lld, reading more\n", *ppos, inode->i_size); 663 read += ret; 664 base += ret; 665 len -= ret; 666 checkeof = 0; 667 goto again; 668 } 669 } 670 if (ret >= 0) 671 ret += read; 672 673 return ret; 674 } 675 676 /* 677 * Take cap references to avoid releasing caps to MDS mid-write. 678 * 679 * If we are synchronous, and write with an old snap context, the OSD 680 * may return EOLDSNAPC. In that case, retry the write.. _after_ 681 * dropping our cap refs and allowing the pending snap to logically 682 * complete _before_ this write occurs. 683 * 684 * If we are near ENOSPC, write synchronously. 685 */ 686 static ssize_t ceph_aio_write(struct kiocb *iocb, const struct iovec *iov, 687 unsigned long nr_segs, loff_t pos) 688 { 689 struct file *file = iocb->ki_filp; 690 struct ceph_file_info *fi = file->private_data; 691 struct inode *inode = file->f_dentry->d_inode; 692 struct ceph_inode_info *ci = ceph_inode(inode); 693 struct ceph_osd_client *osdc = 694 &ceph_sb_to_client(inode->i_sb)->client->osdc; 695 loff_t endoff = pos + iov->iov_len; 696 int want, got = 0; 697 int ret, err; 698 699 if (ceph_snap(inode) != CEPH_NOSNAP) 700 return -EROFS; 701 702 retry_snap: 703 if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL)) 704 return -ENOSPC; 705 __ceph_do_pending_vmtruncate(inode); 706 dout("aio_write %p %llx.%llx %llu~%u getting caps. i_size %llu\n", 707 inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len, 708 inode->i_size); 709 if (fi->fmode & CEPH_FILE_MODE_LAZY) 710 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO; 711 else 712 want = CEPH_CAP_FILE_BUFFER; 713 ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, &got, endoff); 714 if (ret < 0) 715 goto out; 716 717 dout("aio_write %p %llx.%llx %llu~%u got cap refs on %s\n", 718 inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len, 719 ceph_cap_string(got)); 720 721 if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 || 722 (iocb->ki_filp->f_flags & O_DIRECT) || 723 (inode->i_sb->s_flags & MS_SYNCHRONOUS)) { 724 ret = ceph_sync_write(file, iov->iov_base, iov->iov_len, 725 &iocb->ki_pos); 726 } else { 727 ret = generic_file_aio_write(iocb, iov, nr_segs, pos); 728 729 if ((ret >= 0 || ret == -EIOCBQUEUED) && 730 ((file->f_flags & O_SYNC) || IS_SYNC(file->f_mapping->host) 731 || ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_NEARFULL))) { 732 err = vfs_fsync_range(file, pos, pos + ret - 1, 1); 733 if (err < 0) 734 ret = err; 735 } 736 } 737 if (ret >= 0) { 738 int dirty; 739 spin_lock(&inode->i_lock); 740 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR); 741 spin_unlock(&inode->i_lock); 742 if (dirty) 743 __mark_inode_dirty(inode, dirty); 744 } 745 746 out: 747 dout("aio_write %p %llx.%llx %llu~%u dropping cap refs on %s\n", 748 inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len, 749 ceph_cap_string(got)); 750 ceph_put_cap_refs(ci, got); 751 752 if (ret == -EOLDSNAPC) { 753 dout("aio_write %p %llx.%llx %llu~%u got EOLDSNAPC, retrying\n", 754 inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len); 755 goto retry_snap; 756 } 757 758 return ret; 759 } 760 761 /* 762 * llseek. be sure to verify file size on SEEK_END. 763 */ 764 static loff_t ceph_llseek(struct file *file, loff_t offset, int origin) 765 { 766 struct inode *inode = file->f_mapping->host; 767 int ret; 768 769 mutex_lock(&inode->i_mutex); 770 __ceph_do_pending_vmtruncate(inode); 771 switch (origin) { 772 case SEEK_END: 773 ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE); 774 if (ret < 0) { 775 offset = ret; 776 goto out; 777 } 778 offset += inode->i_size; 779 break; 780 case SEEK_CUR: 781 /* 782 * Here we special-case the lseek(fd, 0, SEEK_CUR) 783 * position-querying operation. Avoid rewriting the "same" 784 * f_pos value back to the file because a concurrent read(), 785 * write() or lseek() might have altered it 786 */ 787 if (offset == 0) { 788 offset = file->f_pos; 789 goto out; 790 } 791 offset += file->f_pos; 792 break; 793 } 794 795 if (offset < 0 || offset > inode->i_sb->s_maxbytes) { 796 offset = -EINVAL; 797 goto out; 798 } 799 800 /* Special lock needed here? */ 801 if (offset != file->f_pos) { 802 file->f_pos = offset; 803 file->f_version = 0; 804 } 805 806 out: 807 mutex_unlock(&inode->i_mutex); 808 return offset; 809 } 810 811 const struct file_operations ceph_file_fops = { 812 .open = ceph_open, 813 .release = ceph_release, 814 .llseek = ceph_llseek, 815 .read = do_sync_read, 816 .write = do_sync_write, 817 .aio_read = ceph_aio_read, 818 .aio_write = ceph_aio_write, 819 .mmap = ceph_mmap, 820 .fsync = ceph_fsync, 821 .lock = ceph_lock, 822 .flock = ceph_flock, 823 .splice_read = generic_file_splice_read, 824 .splice_write = generic_file_splice_write, 825 .unlocked_ioctl = ceph_ioctl, 826 .compat_ioctl = ceph_ioctl, 827 }; 828 829