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 out: 58 return req; 59 } 60 61 /* 62 * initialize private struct file data. 63 * if we fail, clean up by dropping fmode reference on the ceph_inode 64 */ 65 static int ceph_init_file(struct inode *inode, struct file *file, int fmode) 66 { 67 struct ceph_file_info *cf; 68 int ret = 0; 69 70 switch (inode->i_mode & S_IFMT) { 71 case S_IFREG: 72 case S_IFDIR: 73 dout("init_file %p %p 0%o (regular)\n", inode, file, 74 inode->i_mode); 75 cf = kmem_cache_alloc(ceph_file_cachep, GFP_NOFS | __GFP_ZERO); 76 if (cf == NULL) { 77 ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */ 78 return -ENOMEM; 79 } 80 cf->fmode = fmode; 81 cf->next_offset = 2; 82 file->private_data = cf; 83 BUG_ON(inode->i_fop->release != ceph_release); 84 break; 85 86 case S_IFLNK: 87 dout("init_file %p %p 0%o (symlink)\n", inode, file, 88 inode->i_mode); 89 ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */ 90 break; 91 92 default: 93 dout("init_file %p %p 0%o (special)\n", inode, file, 94 inode->i_mode); 95 /* 96 * we need to drop the open ref now, since we don't 97 * have .release set to ceph_release. 98 */ 99 ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */ 100 BUG_ON(inode->i_fop->release == ceph_release); 101 102 /* call the proper open fop */ 103 ret = inode->i_fop->open(inode, file); 104 } 105 return ret; 106 } 107 108 /* 109 * If the filp already has private_data, that means the file was 110 * already opened by intent during lookup, and we do nothing. 111 * 112 * If we already have the requisite capabilities, we can satisfy 113 * the open request locally (no need to request new caps from the 114 * MDS). We do, however, need to inform the MDS (asynchronously) 115 * if our wanted caps set expands. 116 */ 117 int ceph_open(struct inode *inode, struct file *file) 118 { 119 struct ceph_inode_info *ci = ceph_inode(inode); 120 struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb); 121 struct ceph_mds_client *mdsc = fsc->mdsc; 122 struct ceph_mds_request *req; 123 struct ceph_file_info *cf = file->private_data; 124 struct inode *parent_inode = NULL; 125 int err; 126 int flags, fmode, wanted; 127 128 if (cf) { 129 dout("open file %p is already opened\n", file); 130 return 0; 131 } 132 133 /* filter out O_CREAT|O_EXCL; vfs did that already. yuck. */ 134 flags = file->f_flags & ~(O_CREAT|O_EXCL); 135 if (S_ISDIR(inode->i_mode)) 136 flags = O_DIRECTORY; /* mds likes to know */ 137 138 dout("open inode %p ino %llx.%llx file %p flags %d (%d)\n", inode, 139 ceph_vinop(inode), file, flags, file->f_flags); 140 fmode = ceph_flags_to_mode(flags); 141 wanted = ceph_caps_for_mode(fmode); 142 143 /* snapped files are read-only */ 144 if (ceph_snap(inode) != CEPH_NOSNAP && (file->f_mode & FMODE_WRITE)) 145 return -EROFS; 146 147 /* trivially open snapdir */ 148 if (ceph_snap(inode) == CEPH_SNAPDIR) { 149 spin_lock(&ci->i_ceph_lock); 150 __ceph_get_fmode(ci, fmode); 151 spin_unlock(&ci->i_ceph_lock); 152 return ceph_init_file(inode, file, fmode); 153 } 154 155 /* 156 * No need to block if we have caps on the auth MDS (for 157 * write) or any MDS (for read). Update wanted set 158 * asynchronously. 159 */ 160 spin_lock(&ci->i_ceph_lock); 161 if (__ceph_is_any_real_caps(ci) && 162 (((fmode & CEPH_FILE_MODE_WR) == 0) || ci->i_auth_cap)) { 163 int mds_wanted = __ceph_caps_mds_wanted(ci); 164 int issued = __ceph_caps_issued(ci, NULL); 165 166 dout("open %p fmode %d want %s issued %s using existing\n", 167 inode, fmode, ceph_cap_string(wanted), 168 ceph_cap_string(issued)); 169 __ceph_get_fmode(ci, fmode); 170 spin_unlock(&ci->i_ceph_lock); 171 172 /* adjust wanted? */ 173 if ((issued & wanted) != wanted && 174 (mds_wanted & wanted) != wanted && 175 ceph_snap(inode) != CEPH_SNAPDIR) 176 ceph_check_caps(ci, 0, NULL); 177 178 return ceph_init_file(inode, file, fmode); 179 } else if (ceph_snap(inode) != CEPH_NOSNAP && 180 (ci->i_snap_caps & wanted) == wanted) { 181 __ceph_get_fmode(ci, fmode); 182 spin_unlock(&ci->i_ceph_lock); 183 return ceph_init_file(inode, file, fmode); 184 } 185 spin_unlock(&ci->i_ceph_lock); 186 187 dout("open fmode %d wants %s\n", fmode, ceph_cap_string(wanted)); 188 req = prepare_open_request(inode->i_sb, flags, 0); 189 if (IS_ERR(req)) { 190 err = PTR_ERR(req); 191 goto out; 192 } 193 req->r_inode = inode; 194 ihold(inode); 195 req->r_num_caps = 1; 196 if (flags & (O_CREAT|O_TRUNC)) 197 parent_inode = ceph_get_dentry_parent_inode(file->f_dentry); 198 err = ceph_mdsc_do_request(mdsc, parent_inode, req); 199 iput(parent_inode); 200 if (!err) 201 err = ceph_init_file(inode, file, req->r_fmode); 202 ceph_mdsc_put_request(req); 203 dout("open result=%d on %llx.%llx\n", err, ceph_vinop(inode)); 204 out: 205 return err; 206 } 207 208 209 /* 210 * Do a lookup + open with a single request. 211 * 212 * If this succeeds, but some subsequent check in the vfs 213 * may_open() fails, the struct *file gets cleaned up (i.e. 214 * ceph_release gets called). So fear not! 215 */ 216 int ceph_lookup_open(struct inode *dir, struct dentry *dentry, 217 struct file *file, unsigned flags, umode_t mode, 218 int *opened) 219 { 220 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb); 221 struct ceph_mds_client *mdsc = fsc->mdsc; 222 struct ceph_mds_request *req; 223 struct dentry *ret; 224 int err; 225 226 dout("ceph_lookup_open dentry %p '%.*s' flags %d mode 0%o\n", 227 dentry, dentry->d_name.len, dentry->d_name.name, flags, mode); 228 229 /* do the open */ 230 req = prepare_open_request(dir->i_sb, flags, mode); 231 if (IS_ERR(req)) 232 return PTR_ERR(req); 233 req->r_dentry = dget(dentry); 234 req->r_num_caps = 2; 235 if (flags & O_CREAT) { 236 req->r_dentry_drop = CEPH_CAP_FILE_SHARED; 237 req->r_dentry_unless = CEPH_CAP_FILE_EXCL; 238 } 239 req->r_locked_dir = dir; /* caller holds dir->i_mutex */ 240 err = ceph_mdsc_do_request(mdsc, 241 (flags & (O_CREAT|O_TRUNC)) ? dir : NULL, 242 req); 243 err = ceph_handle_snapdir(req, dentry, err); 244 if (err) 245 goto out; 246 if ((flags & O_CREAT) && !req->r_reply_info.head->is_dentry) 247 err = ceph_handle_notrace_create(dir, dentry); 248 if (err) 249 goto out; 250 err = finish_open(file, req->r_dentry, ceph_open, opened); 251 out: 252 ret = ceph_finish_lookup(req, dentry, err); 253 ceph_mdsc_put_request(req); 254 dout("ceph_lookup_open result=%p\n", ret); 255 256 if (IS_ERR(ret)) 257 return PTR_ERR(ret); 258 259 dput(ret); 260 return err; 261 } 262 263 int ceph_release(struct inode *inode, struct file *file) 264 { 265 struct ceph_inode_info *ci = ceph_inode(inode); 266 struct ceph_file_info *cf = file->private_data; 267 268 dout("release inode %p file %p\n", inode, file); 269 ceph_put_fmode(ci, cf->fmode); 270 if (cf->last_readdir) 271 ceph_mdsc_put_request(cf->last_readdir); 272 kfree(cf->last_name); 273 kfree(cf->dir_info); 274 dput(cf->dentry); 275 kmem_cache_free(ceph_file_cachep, cf); 276 277 /* wake up anyone waiting for caps on this inode */ 278 wake_up_all(&ci->i_cap_wq); 279 return 0; 280 } 281 282 /* 283 * Read a range of bytes striped over one or more objects. Iterate over 284 * objects we stripe over. (That's not atomic, but good enough for now.) 285 * 286 * If we get a short result from the OSD, check against i_size; we need to 287 * only return a short read to the caller if we hit EOF. 288 */ 289 static int striped_read(struct inode *inode, 290 u64 off, u64 len, 291 struct page **pages, int num_pages, 292 int *checkeof, bool o_direct, 293 unsigned long buf_align) 294 { 295 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 296 struct ceph_inode_info *ci = ceph_inode(inode); 297 u64 pos, this_len; 298 int io_align, page_align; 299 int left, pages_left; 300 int read; 301 struct page **page_pos; 302 int ret; 303 bool hit_stripe, was_short; 304 305 /* 306 * we may need to do multiple reads. not atomic, unfortunately. 307 */ 308 pos = off; 309 left = len; 310 page_pos = pages; 311 pages_left = num_pages; 312 read = 0; 313 io_align = off & ~PAGE_MASK; 314 315 more: 316 if (o_direct) 317 page_align = (pos - io_align + buf_align) & ~PAGE_MASK; 318 else 319 page_align = pos & ~PAGE_MASK; 320 this_len = left; 321 ret = ceph_osdc_readpages(&fsc->client->osdc, ceph_vino(inode), 322 &ci->i_layout, pos, &this_len, 323 ci->i_truncate_seq, 324 ci->i_truncate_size, 325 page_pos, pages_left, page_align); 326 if (ret == -ENOENT) 327 ret = 0; 328 hit_stripe = this_len < left; 329 was_short = ret >= 0 && ret < this_len; 330 dout("striped_read %llu~%u (read %u) got %d%s%s\n", pos, left, read, 331 ret, hit_stripe ? " HITSTRIPE" : "", was_short ? " SHORT" : ""); 332 333 if (ret > 0) { 334 int didpages = (page_align + ret) >> PAGE_CACHE_SHIFT; 335 336 if (read < pos - off) { 337 dout(" zero gap %llu to %llu\n", off + read, pos); 338 ceph_zero_page_vector_range(page_align + read, 339 pos - off - read, pages); 340 } 341 pos += ret; 342 read = pos - off; 343 left -= ret; 344 page_pos += didpages; 345 pages_left -= didpages; 346 347 /* hit stripe? */ 348 if (left && hit_stripe) 349 goto more; 350 } 351 352 if (was_short) { 353 /* did we bounce off eof? */ 354 if (pos + left > inode->i_size) 355 *checkeof = 1; 356 357 /* zero trailing bytes (inside i_size) */ 358 if (left > 0 && pos < inode->i_size) { 359 if (pos + left > inode->i_size) 360 left = inode->i_size - pos; 361 362 dout("zero tail %d\n", left); 363 ceph_zero_page_vector_range(page_align + read, left, 364 pages); 365 read += left; 366 } 367 } 368 369 if (ret >= 0) 370 ret = read; 371 dout("striped_read returns %d\n", ret); 372 return ret; 373 } 374 375 /* 376 * Completely synchronous read and write methods. Direct from __user 377 * buffer to osd, or directly to user pages (if O_DIRECT). 378 * 379 * If the read spans object boundary, just do multiple reads. 380 */ 381 static ssize_t ceph_sync_read(struct file *file, char __user *data, 382 unsigned len, loff_t *poff, int *checkeof) 383 { 384 struct inode *inode = file->f_dentry->d_inode; 385 struct page **pages; 386 u64 off = *poff; 387 int num_pages, ret; 388 389 dout("sync_read on file %p %llu~%u %s\n", file, off, len, 390 (file->f_flags & O_DIRECT) ? "O_DIRECT" : ""); 391 392 if (file->f_flags & O_DIRECT) { 393 num_pages = calc_pages_for((unsigned long)data, len); 394 pages = ceph_get_direct_page_vector(data, num_pages, true); 395 } else { 396 num_pages = calc_pages_for(off, len); 397 pages = ceph_alloc_page_vector(num_pages, GFP_NOFS); 398 } 399 if (IS_ERR(pages)) 400 return PTR_ERR(pages); 401 402 /* 403 * flush any page cache pages in this range. this 404 * will make concurrent normal and sync io slow, 405 * but it will at least behave sensibly when they are 406 * in sequence. 407 */ 408 ret = filemap_write_and_wait(inode->i_mapping); 409 if (ret < 0) 410 goto done; 411 412 ret = striped_read(inode, off, len, pages, num_pages, checkeof, 413 file->f_flags & O_DIRECT, 414 (unsigned long)data & ~PAGE_MASK); 415 416 if (ret >= 0 && (file->f_flags & O_DIRECT) == 0) 417 ret = ceph_copy_page_vector_to_user(pages, data, off, ret); 418 if (ret >= 0) 419 *poff = off + ret; 420 421 done: 422 if (file->f_flags & O_DIRECT) 423 ceph_put_page_vector(pages, num_pages, true); 424 else 425 ceph_release_page_vector(pages, num_pages); 426 dout("sync_read result %d\n", ret); 427 return ret; 428 } 429 430 /* 431 * Write commit callback, called if we requested both an ACK and 432 * ONDISK commit reply from the OSD. 433 */ 434 static void sync_write_commit(struct ceph_osd_request *req, 435 struct ceph_msg *msg) 436 { 437 struct ceph_inode_info *ci = ceph_inode(req->r_inode); 438 439 dout("sync_write_commit %p tid %llu\n", req, req->r_tid); 440 spin_lock(&ci->i_unsafe_lock); 441 list_del_init(&req->r_unsafe_item); 442 spin_unlock(&ci->i_unsafe_lock); 443 ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR); 444 } 445 446 /* 447 * Synchronous write, straight from __user pointer or user pages (if 448 * O_DIRECT). 449 * 450 * If write spans object boundary, just do multiple writes. (For a 451 * correct atomic write, we should e.g. take write locks on all 452 * objects, rollback on failure, etc.) 453 */ 454 static ssize_t ceph_sync_write(struct file *file, const char __user *data, 455 size_t left, loff_t *offset) 456 { 457 struct inode *inode = file->f_dentry->d_inode; 458 struct ceph_inode_info *ci = ceph_inode(inode); 459 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 460 struct ceph_osd_request *req; 461 struct page **pages; 462 int num_pages; 463 long long unsigned pos; 464 u64 len; 465 int written = 0; 466 int flags; 467 int do_sync = 0; 468 int check_caps = 0; 469 int page_align, io_align; 470 unsigned long buf_align; 471 int ret; 472 struct timespec mtime = CURRENT_TIME; 473 474 if (ceph_snap(file->f_dentry->d_inode) != CEPH_NOSNAP) 475 return -EROFS; 476 477 dout("sync_write on file %p %lld~%u %s\n", file, *offset, 478 (unsigned)left, (file->f_flags & O_DIRECT) ? "O_DIRECT" : ""); 479 480 if (file->f_flags & O_APPEND) 481 pos = i_size_read(inode); 482 else 483 pos = *offset; 484 485 ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + left); 486 if (ret < 0) 487 return ret; 488 489 ret = invalidate_inode_pages2_range(inode->i_mapping, 490 pos >> PAGE_CACHE_SHIFT, 491 (pos + left) >> PAGE_CACHE_SHIFT); 492 if (ret < 0) 493 dout("invalidate_inode_pages2_range returned %d\n", ret); 494 495 flags = CEPH_OSD_FLAG_ORDERSNAP | 496 CEPH_OSD_FLAG_ONDISK | 497 CEPH_OSD_FLAG_WRITE; 498 if ((file->f_flags & (O_SYNC|O_DIRECT)) == 0) 499 flags |= CEPH_OSD_FLAG_ACK; 500 else 501 do_sync = 1; 502 503 /* 504 * we may need to do multiple writes here if we span an object 505 * boundary. this isn't atomic, unfortunately. :( 506 */ 507 more: 508 io_align = pos & ~PAGE_MASK; 509 buf_align = (unsigned long)data & ~PAGE_MASK; 510 len = left; 511 if (file->f_flags & O_DIRECT) { 512 /* write from beginning of first page, regardless of 513 io alignment */ 514 page_align = (pos - io_align + buf_align) & ~PAGE_MASK; 515 num_pages = calc_pages_for((unsigned long)data, len); 516 } else { 517 page_align = pos & ~PAGE_MASK; 518 num_pages = calc_pages_for(pos, len); 519 } 520 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout, 521 ceph_vino(inode), pos, &len, 522 CEPH_OSD_OP_WRITE, flags, 523 ci->i_snap_realm->cached_context, 524 do_sync, 525 ci->i_truncate_seq, ci->i_truncate_size, 526 &mtime, false, 2, page_align); 527 if (!req) 528 return -ENOMEM; 529 530 if (file->f_flags & O_DIRECT) { 531 pages = ceph_get_direct_page_vector(data, num_pages, false); 532 if (IS_ERR(pages)) { 533 ret = PTR_ERR(pages); 534 goto out; 535 } 536 537 /* 538 * throw out any page cache pages in this range. this 539 * may block. 540 */ 541 truncate_inode_pages_range(inode->i_mapping, pos, 542 (pos+len) | (PAGE_CACHE_SIZE-1)); 543 } else { 544 pages = ceph_alloc_page_vector(num_pages, GFP_NOFS); 545 if (IS_ERR(pages)) { 546 ret = PTR_ERR(pages); 547 goto out; 548 } 549 ret = ceph_copy_user_to_page_vector(pages, data, pos, len); 550 if (ret < 0) { 551 ceph_release_page_vector(pages, num_pages); 552 goto out; 553 } 554 555 if ((file->f_flags & O_SYNC) == 0) { 556 /* get a second commit callback */ 557 req->r_safe_callback = sync_write_commit; 558 req->r_own_pages = 1; 559 } 560 } 561 req->r_pages = pages; 562 req->r_num_pages = num_pages; 563 req->r_inode = inode; 564 565 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false); 566 if (!ret) { 567 if (req->r_safe_callback) { 568 /* 569 * Add to inode unsafe list only after we 570 * start_request so that a tid has been assigned. 571 */ 572 spin_lock(&ci->i_unsafe_lock); 573 list_add_tail(&req->r_unsafe_item, 574 &ci->i_unsafe_writes); 575 spin_unlock(&ci->i_unsafe_lock); 576 ceph_get_cap_refs(ci, CEPH_CAP_FILE_WR); 577 } 578 579 ret = ceph_osdc_wait_request(&fsc->client->osdc, req); 580 if (ret < 0 && req->r_safe_callback) { 581 spin_lock(&ci->i_unsafe_lock); 582 list_del_init(&req->r_unsafe_item); 583 spin_unlock(&ci->i_unsafe_lock); 584 ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR); 585 } 586 } 587 588 if (file->f_flags & O_DIRECT) 589 ceph_put_page_vector(pages, num_pages, false); 590 else if (file->f_flags & O_SYNC) 591 ceph_release_page_vector(pages, num_pages); 592 593 out: 594 ceph_osdc_put_request(req); 595 if (ret == 0) { 596 pos += len; 597 written += len; 598 left -= len; 599 data += written; 600 if (left) 601 goto more; 602 603 ret = written; 604 *offset = pos; 605 if (pos > i_size_read(inode)) 606 check_caps = ceph_inode_set_size(inode, pos); 607 if (check_caps) 608 ceph_check_caps(ceph_inode(inode), CHECK_CAPS_AUTHONLY, 609 NULL); 610 } 611 return ret; 612 } 613 614 /* 615 * Wrap generic_file_aio_read with checks for cap bits on the inode. 616 * Atomically grab references, so that those bits are not released 617 * back to the MDS mid-read. 618 * 619 * Hmm, the sync read case isn't actually async... should it be? 620 */ 621 static ssize_t ceph_aio_read(struct kiocb *iocb, const struct iovec *iov, 622 unsigned long nr_segs, loff_t pos) 623 { 624 struct file *filp = iocb->ki_filp; 625 struct ceph_file_info *fi = filp->private_data; 626 loff_t *ppos = &iocb->ki_pos; 627 size_t len = iov->iov_len; 628 struct inode *inode = filp->f_dentry->d_inode; 629 struct ceph_inode_info *ci = ceph_inode(inode); 630 void __user *base = iov->iov_base; 631 ssize_t ret; 632 int want, got = 0; 633 int checkeof = 0, read = 0; 634 635 dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n", 636 inode, ceph_vinop(inode), pos, (unsigned)len, inode); 637 again: 638 __ceph_do_pending_vmtruncate(inode); 639 if (fi->fmode & CEPH_FILE_MODE_LAZY) 640 want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO; 641 else 642 want = CEPH_CAP_FILE_CACHE; 643 ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, &got, -1); 644 if (ret < 0) 645 goto out; 646 dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n", 647 inode, ceph_vinop(inode), pos, (unsigned)len, 648 ceph_cap_string(got)); 649 650 if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 || 651 (iocb->ki_filp->f_flags & O_DIRECT) || 652 (inode->i_sb->s_flags & MS_SYNCHRONOUS) || 653 (fi->flags & CEPH_F_SYNC)) 654 /* hmm, this isn't really async... */ 655 ret = ceph_sync_read(filp, base, len, ppos, &checkeof); 656 else 657 ret = generic_file_aio_read(iocb, iov, nr_segs, pos); 658 659 out: 660 dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n", 661 inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret); 662 ceph_put_cap_refs(ci, got); 663 664 if (checkeof && ret >= 0) { 665 int statret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE); 666 667 /* hit EOF or hole? */ 668 if (statret == 0 && *ppos < inode->i_size) { 669 dout("aio_read sync_read hit hole, ppos %lld < size %lld, reading more\n", *ppos, inode->i_size); 670 read += ret; 671 base += ret; 672 len -= ret; 673 checkeof = 0; 674 goto again; 675 } 676 } 677 if (ret >= 0) 678 ret += read; 679 680 return ret; 681 } 682 683 /* 684 * Take cap references to avoid releasing caps to MDS mid-write. 685 * 686 * If we are synchronous, and write with an old snap context, the OSD 687 * may return EOLDSNAPC. In that case, retry the write.. _after_ 688 * dropping our cap refs and allowing the pending snap to logically 689 * complete _before_ this write occurs. 690 * 691 * If we are near ENOSPC, write synchronously. 692 */ 693 static ssize_t ceph_aio_write(struct kiocb *iocb, const struct iovec *iov, 694 unsigned long nr_segs, loff_t pos) 695 { 696 struct file *file = iocb->ki_filp; 697 struct ceph_file_info *fi = file->private_data; 698 struct inode *inode = file->f_dentry->d_inode; 699 struct ceph_inode_info *ci = ceph_inode(inode); 700 struct ceph_osd_client *osdc = 701 &ceph_sb_to_client(inode->i_sb)->client->osdc; 702 loff_t endoff = pos + iov->iov_len; 703 int want, got = 0; 704 int ret, err; 705 706 if (ceph_snap(inode) != CEPH_NOSNAP) 707 return -EROFS; 708 709 retry_snap: 710 if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL)) 711 return -ENOSPC; 712 __ceph_do_pending_vmtruncate(inode); 713 dout("aio_write %p %llx.%llx %llu~%u getting caps. i_size %llu\n", 714 inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len, 715 inode->i_size); 716 if (fi->fmode & CEPH_FILE_MODE_LAZY) 717 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO; 718 else 719 want = CEPH_CAP_FILE_BUFFER; 720 ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, &got, endoff); 721 if (ret < 0) 722 goto out_put; 723 724 dout("aio_write %p %llx.%llx %llu~%u got cap refs on %s\n", 725 inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len, 726 ceph_cap_string(got)); 727 728 if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 || 729 (iocb->ki_filp->f_flags & O_DIRECT) || 730 (inode->i_sb->s_flags & MS_SYNCHRONOUS) || 731 (fi->flags & CEPH_F_SYNC)) { 732 ret = ceph_sync_write(file, iov->iov_base, iov->iov_len, 733 &iocb->ki_pos); 734 } else { 735 /* 736 * buffered write; drop Fw early to avoid slow 737 * revocation if we get stuck on balance_dirty_pages 738 */ 739 int dirty; 740 741 spin_lock(&ci->i_ceph_lock); 742 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR); 743 spin_unlock(&ci->i_ceph_lock); 744 ceph_put_cap_refs(ci, got); 745 746 ret = generic_file_aio_write(iocb, iov, nr_segs, pos); 747 if ((ret >= 0 || ret == -EIOCBQUEUED) && 748 ((file->f_flags & O_SYNC) || IS_SYNC(file->f_mapping->host) 749 || ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_NEARFULL))) { 750 err = vfs_fsync_range(file, pos, pos + ret - 1, 1); 751 if (err < 0) 752 ret = err; 753 } 754 755 if (dirty) 756 __mark_inode_dirty(inode, dirty); 757 goto out; 758 } 759 760 if (ret >= 0) { 761 int dirty; 762 spin_lock(&ci->i_ceph_lock); 763 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR); 764 spin_unlock(&ci->i_ceph_lock); 765 if (dirty) 766 __mark_inode_dirty(inode, dirty); 767 } 768 769 out_put: 770 dout("aio_write %p %llx.%llx %llu~%u dropping cap refs on %s\n", 771 inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len, 772 ceph_cap_string(got)); 773 ceph_put_cap_refs(ci, got); 774 775 out: 776 if (ret == -EOLDSNAPC) { 777 dout("aio_write %p %llx.%llx %llu~%u got EOLDSNAPC, retrying\n", 778 inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len); 779 goto retry_snap; 780 } 781 782 return ret; 783 } 784 785 /* 786 * llseek. be sure to verify file size on SEEK_END. 787 */ 788 static loff_t ceph_llseek(struct file *file, loff_t offset, int origin) 789 { 790 struct inode *inode = file->f_mapping->host; 791 int ret; 792 793 mutex_lock(&inode->i_mutex); 794 __ceph_do_pending_vmtruncate(inode); 795 796 if (origin == SEEK_END || origin == SEEK_DATA || origin == SEEK_HOLE) { 797 ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE); 798 if (ret < 0) { 799 offset = ret; 800 goto out; 801 } 802 } 803 804 switch (origin) { 805 case SEEK_END: 806 offset += inode->i_size; 807 break; 808 case SEEK_CUR: 809 /* 810 * Here we special-case the lseek(fd, 0, SEEK_CUR) 811 * position-querying operation. Avoid rewriting the "same" 812 * f_pos value back to the file because a concurrent read(), 813 * write() or lseek() might have altered it 814 */ 815 if (offset == 0) { 816 offset = file->f_pos; 817 goto out; 818 } 819 offset += file->f_pos; 820 break; 821 case SEEK_DATA: 822 if (offset >= inode->i_size) { 823 ret = -ENXIO; 824 goto out; 825 } 826 break; 827 case SEEK_HOLE: 828 if (offset >= inode->i_size) { 829 ret = -ENXIO; 830 goto out; 831 } 832 offset = inode->i_size; 833 break; 834 } 835 836 if (offset < 0 || offset > inode->i_sb->s_maxbytes) { 837 offset = -EINVAL; 838 goto out; 839 } 840 841 /* Special lock needed here? */ 842 if (offset != file->f_pos) { 843 file->f_pos = offset; 844 file->f_version = 0; 845 } 846 847 out: 848 mutex_unlock(&inode->i_mutex); 849 return offset; 850 } 851 852 const struct file_operations ceph_file_fops = { 853 .open = ceph_open, 854 .release = ceph_release, 855 .llseek = ceph_llseek, 856 .read = do_sync_read, 857 .write = do_sync_write, 858 .aio_read = ceph_aio_read, 859 .aio_write = ceph_aio_write, 860 .mmap = ceph_mmap, 861 .fsync = ceph_fsync, 862 .lock = ceph_lock, 863 .flock = ceph_flock, 864 .splice_read = generic_file_splice_read, 865 .splice_write = generic_file_splice_write, 866 .unlocked_ioctl = ceph_ioctl, 867 .compat_ioctl = ceph_ioctl, 868 }; 869 870