1 #include <linux/ceph/ceph_debug.h> 2 3 #include <linux/backing-dev.h> 4 #include <linux/fs.h> 5 #include <linux/mm.h> 6 #include <linux/pagemap.h> 7 #include <linux/writeback.h> /* generic_writepages */ 8 #include <linux/slab.h> 9 #include <linux/pagevec.h> 10 #include <linux/task_io_accounting_ops.h> 11 #include <linux/signal.h> 12 13 #include "super.h" 14 #include "mds_client.h" 15 #include "cache.h" 16 #include <linux/ceph/osd_client.h> 17 18 /* 19 * Ceph address space ops. 20 * 21 * There are a few funny things going on here. 22 * 23 * The page->private field is used to reference a struct 24 * ceph_snap_context for _every_ dirty page. This indicates which 25 * snapshot the page was logically dirtied in, and thus which snap 26 * context needs to be associated with the osd write during writeback. 27 * 28 * Similarly, struct ceph_inode_info maintains a set of counters to 29 * count dirty pages on the inode. In the absence of snapshots, 30 * i_wrbuffer_ref == i_wrbuffer_ref_head == the dirty page count. 31 * 32 * When a snapshot is taken (that is, when the client receives 33 * notification that a snapshot was taken), each inode with caps and 34 * with dirty pages (dirty pages implies there is a cap) gets a new 35 * ceph_cap_snap in the i_cap_snaps list (which is sorted in ascending 36 * order, new snaps go to the tail). The i_wrbuffer_ref_head count is 37 * moved to capsnap->dirty. (Unless a sync write is currently in 38 * progress. In that case, the capsnap is said to be "pending", new 39 * writes cannot start, and the capsnap isn't "finalized" until the 40 * write completes (or fails) and a final size/mtime for the inode for 41 * that snap can be settled upon.) i_wrbuffer_ref_head is reset to 0. 42 * 43 * On writeback, we must submit writes to the osd IN SNAP ORDER. So, 44 * we look for the first capsnap in i_cap_snaps and write out pages in 45 * that snap context _only_. Then we move on to the next capsnap, 46 * eventually reaching the "live" or "head" context (i.e., pages that 47 * are not yet snapped) and are writing the most recently dirtied 48 * pages. 49 * 50 * Invalidate and so forth must take care to ensure the dirty page 51 * accounting is preserved. 52 */ 53 54 #define CONGESTION_ON_THRESH(congestion_kb) (congestion_kb >> (PAGE_SHIFT-10)) 55 #define CONGESTION_OFF_THRESH(congestion_kb) \ 56 (CONGESTION_ON_THRESH(congestion_kb) - \ 57 (CONGESTION_ON_THRESH(congestion_kb) >> 2)) 58 59 static inline struct ceph_snap_context *page_snap_context(struct page *page) 60 { 61 if (PagePrivate(page)) 62 return (void *)page->private; 63 return NULL; 64 } 65 66 /* 67 * Dirty a page. Optimistically adjust accounting, on the assumption 68 * that we won't race with invalidate. If we do, readjust. 69 */ 70 static int ceph_set_page_dirty(struct page *page) 71 { 72 struct address_space *mapping = page->mapping; 73 struct inode *inode; 74 struct ceph_inode_info *ci; 75 struct ceph_snap_context *snapc; 76 int ret; 77 78 if (unlikely(!mapping)) 79 return !TestSetPageDirty(page); 80 81 if (PageDirty(page)) { 82 dout("%p set_page_dirty %p idx %lu -- already dirty\n", 83 mapping->host, page, page->index); 84 BUG_ON(!PagePrivate(page)); 85 return 0; 86 } 87 88 inode = mapping->host; 89 ci = ceph_inode(inode); 90 91 /* dirty the head */ 92 spin_lock(&ci->i_ceph_lock); 93 BUG_ON(ci->i_wr_ref == 0); // caller should hold Fw reference 94 if (__ceph_have_pending_cap_snap(ci)) { 95 struct ceph_cap_snap *capsnap = 96 list_last_entry(&ci->i_cap_snaps, 97 struct ceph_cap_snap, 98 ci_item); 99 snapc = ceph_get_snap_context(capsnap->context); 100 capsnap->dirty_pages++; 101 } else { 102 BUG_ON(!ci->i_head_snapc); 103 snapc = ceph_get_snap_context(ci->i_head_snapc); 104 ++ci->i_wrbuffer_ref_head; 105 } 106 if (ci->i_wrbuffer_ref == 0) 107 ihold(inode); 108 ++ci->i_wrbuffer_ref; 109 dout("%p set_page_dirty %p idx %lu head %d/%d -> %d/%d " 110 "snapc %p seq %lld (%d snaps)\n", 111 mapping->host, page, page->index, 112 ci->i_wrbuffer_ref-1, ci->i_wrbuffer_ref_head-1, 113 ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head, 114 snapc, snapc->seq, snapc->num_snaps); 115 spin_unlock(&ci->i_ceph_lock); 116 117 /* 118 * Reference snap context in page->private. Also set 119 * PagePrivate so that we get invalidatepage callback. 120 */ 121 BUG_ON(PagePrivate(page)); 122 page->private = (unsigned long)snapc; 123 SetPagePrivate(page); 124 125 ret = __set_page_dirty_nobuffers(page); 126 WARN_ON(!PageLocked(page)); 127 WARN_ON(!page->mapping); 128 129 return ret; 130 } 131 132 /* 133 * If we are truncating the full page (i.e. offset == 0), adjust the 134 * dirty page counters appropriately. Only called if there is private 135 * data on the page. 136 */ 137 static void ceph_invalidatepage(struct page *page, unsigned int offset, 138 unsigned int length) 139 { 140 struct inode *inode; 141 struct ceph_inode_info *ci; 142 struct ceph_snap_context *snapc = page_snap_context(page); 143 144 inode = page->mapping->host; 145 ci = ceph_inode(inode); 146 147 if (offset != 0 || length != PAGE_SIZE) { 148 dout("%p invalidatepage %p idx %lu partial dirty page %u~%u\n", 149 inode, page, page->index, offset, length); 150 return; 151 } 152 153 ceph_invalidate_fscache_page(inode, page); 154 155 if (!PagePrivate(page)) 156 return; 157 158 /* 159 * We can get non-dirty pages here due to races between 160 * set_page_dirty and truncate_complete_page; just spit out a 161 * warning, in case we end up with accounting problems later. 162 */ 163 if (!PageDirty(page)) 164 pr_err("%p invalidatepage %p page not dirty\n", inode, page); 165 166 ClearPageChecked(page); 167 168 dout("%p invalidatepage %p idx %lu full dirty page\n", 169 inode, page, page->index); 170 171 ceph_put_wrbuffer_cap_refs(ci, 1, snapc); 172 ceph_put_snap_context(snapc); 173 page->private = 0; 174 ClearPagePrivate(page); 175 } 176 177 static int ceph_releasepage(struct page *page, gfp_t g) 178 { 179 dout("%p releasepage %p idx %lu (%sdirty)\n", page->mapping->host, 180 page, page->index, PageDirty(page) ? "" : "not "); 181 182 /* Can we release the page from the cache? */ 183 if (!ceph_release_fscache_page(page, g)) 184 return 0; 185 186 return !PagePrivate(page); 187 } 188 189 /* 190 * read a single page, without unlocking it. 191 */ 192 static int readpage_nounlock(struct file *filp, struct page *page) 193 { 194 struct inode *inode = file_inode(filp); 195 struct ceph_inode_info *ci = ceph_inode(inode); 196 struct ceph_osd_client *osdc = 197 &ceph_inode_to_client(inode)->client->osdc; 198 int err = 0; 199 u64 off = page_offset(page); 200 u64 len = PAGE_SIZE; 201 202 if (off >= i_size_read(inode)) { 203 zero_user_segment(page, 0, PAGE_SIZE); 204 SetPageUptodate(page); 205 return 0; 206 } 207 208 if (ci->i_inline_version != CEPH_INLINE_NONE) { 209 /* 210 * Uptodate inline data should have been added 211 * into page cache while getting Fcr caps. 212 */ 213 if (off == 0) 214 return -EINVAL; 215 zero_user_segment(page, 0, PAGE_SIZE); 216 SetPageUptodate(page); 217 return 0; 218 } 219 220 err = ceph_readpage_from_fscache(inode, page); 221 if (err == 0) 222 goto out; 223 224 dout("readpage inode %p file %p page %p index %lu\n", 225 inode, filp, page, page->index); 226 err = ceph_osdc_readpages(osdc, ceph_vino(inode), &ci->i_layout, 227 off, &len, 228 ci->i_truncate_seq, ci->i_truncate_size, 229 &page, 1, 0); 230 if (err == -ENOENT) 231 err = 0; 232 if (err < 0) { 233 SetPageError(page); 234 ceph_fscache_readpage_cancel(inode, page); 235 goto out; 236 } 237 if (err < PAGE_SIZE) 238 /* zero fill remainder of page */ 239 zero_user_segment(page, err, PAGE_SIZE); 240 else 241 flush_dcache_page(page); 242 243 SetPageUptodate(page); 244 ceph_readpage_to_fscache(inode, page); 245 246 out: 247 return err < 0 ? err : 0; 248 } 249 250 static int ceph_readpage(struct file *filp, struct page *page) 251 { 252 int r = readpage_nounlock(filp, page); 253 unlock_page(page); 254 return r; 255 } 256 257 /* 258 * Finish an async read(ahead) op. 259 */ 260 static void finish_read(struct ceph_osd_request *req) 261 { 262 struct inode *inode = req->r_inode; 263 struct ceph_osd_data *osd_data; 264 int rc = req->r_result <= 0 ? req->r_result : 0; 265 int bytes = req->r_result >= 0 ? req->r_result : 0; 266 int num_pages; 267 int i; 268 269 dout("finish_read %p req %p rc %d bytes %d\n", inode, req, rc, bytes); 270 271 /* unlock all pages, zeroing any data we didn't read */ 272 osd_data = osd_req_op_extent_osd_data(req, 0); 273 BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES); 274 num_pages = calc_pages_for((u64)osd_data->alignment, 275 (u64)osd_data->length); 276 for (i = 0; i < num_pages; i++) { 277 struct page *page = osd_data->pages[i]; 278 279 if (rc < 0 && rc != -ENOENT) { 280 ceph_fscache_readpage_cancel(inode, page); 281 goto unlock; 282 } 283 if (bytes < (int)PAGE_SIZE) { 284 /* zero (remainder of) page */ 285 int s = bytes < 0 ? 0 : bytes; 286 zero_user_segment(page, s, PAGE_SIZE); 287 } 288 dout("finish_read %p uptodate %p idx %lu\n", inode, page, 289 page->index); 290 flush_dcache_page(page); 291 SetPageUptodate(page); 292 ceph_readpage_to_fscache(inode, page); 293 unlock: 294 unlock_page(page); 295 put_page(page); 296 bytes -= PAGE_SIZE; 297 } 298 kfree(osd_data->pages); 299 } 300 301 /* 302 * start an async read(ahead) operation. return nr_pages we submitted 303 * a read for on success, or negative error code. 304 */ 305 static int start_read(struct inode *inode, struct list_head *page_list, int max) 306 { 307 struct ceph_osd_client *osdc = 308 &ceph_inode_to_client(inode)->client->osdc; 309 struct ceph_inode_info *ci = ceph_inode(inode); 310 struct page *page = list_entry(page_list->prev, struct page, lru); 311 struct ceph_vino vino; 312 struct ceph_osd_request *req; 313 u64 off; 314 u64 len; 315 int i; 316 struct page **pages; 317 pgoff_t next_index; 318 int nr_pages = 0; 319 int got = 0; 320 int ret = 0; 321 322 if (!current->journal_info) { 323 /* caller of readpages does not hold buffer and read caps 324 * (fadvise, madvise and readahead cases) */ 325 int want = CEPH_CAP_FILE_CACHE; 326 ret = ceph_try_get_caps(ci, CEPH_CAP_FILE_RD, want, &got); 327 if (ret < 0) { 328 dout("start_read %p, error getting cap\n", inode); 329 } else if (!(got & want)) { 330 dout("start_read %p, no cache cap\n", inode); 331 ret = 0; 332 } 333 if (ret <= 0) { 334 if (got) 335 ceph_put_cap_refs(ci, got); 336 while (!list_empty(page_list)) { 337 page = list_entry(page_list->prev, 338 struct page, lru); 339 list_del(&page->lru); 340 put_page(page); 341 } 342 return ret; 343 } 344 } 345 346 off = (u64) page_offset(page); 347 348 /* count pages */ 349 next_index = page->index; 350 list_for_each_entry_reverse(page, page_list, lru) { 351 if (page->index != next_index) 352 break; 353 nr_pages++; 354 next_index++; 355 if (max && nr_pages == max) 356 break; 357 } 358 len = nr_pages << PAGE_SHIFT; 359 dout("start_read %p nr_pages %d is %lld~%lld\n", inode, nr_pages, 360 off, len); 361 vino = ceph_vino(inode); 362 req = ceph_osdc_new_request(osdc, &ci->i_layout, vino, off, &len, 363 0, 1, CEPH_OSD_OP_READ, 364 CEPH_OSD_FLAG_READ, NULL, 365 ci->i_truncate_seq, ci->i_truncate_size, 366 false); 367 if (IS_ERR(req)) { 368 ret = PTR_ERR(req); 369 goto out; 370 } 371 372 /* build page vector */ 373 nr_pages = calc_pages_for(0, len); 374 pages = kmalloc(sizeof(*pages) * nr_pages, GFP_KERNEL); 375 if (!pages) { 376 ret = -ENOMEM; 377 goto out_put; 378 } 379 for (i = 0; i < nr_pages; ++i) { 380 page = list_entry(page_list->prev, struct page, lru); 381 BUG_ON(PageLocked(page)); 382 list_del(&page->lru); 383 384 dout("start_read %p adding %p idx %lu\n", inode, page, 385 page->index); 386 if (add_to_page_cache_lru(page, &inode->i_data, page->index, 387 GFP_KERNEL)) { 388 ceph_fscache_uncache_page(inode, page); 389 put_page(page); 390 dout("start_read %p add_to_page_cache failed %p\n", 391 inode, page); 392 nr_pages = i; 393 if (nr_pages > 0) { 394 len = nr_pages << PAGE_SHIFT; 395 osd_req_op_extent_update(req, 0, len); 396 break; 397 } 398 goto out_pages; 399 } 400 pages[i] = page; 401 } 402 osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0, false, false); 403 req->r_callback = finish_read; 404 req->r_inode = inode; 405 406 dout("start_read %p starting %p %lld~%lld\n", inode, req, off, len); 407 ret = ceph_osdc_start_request(osdc, req, false); 408 if (ret < 0) 409 goto out_pages; 410 ceph_osdc_put_request(req); 411 412 /* After adding locked pages to page cache, the inode holds cache cap. 413 * So we can drop our cap refs. */ 414 if (got) 415 ceph_put_cap_refs(ci, got); 416 417 return nr_pages; 418 419 out_pages: 420 for (i = 0; i < nr_pages; ++i) { 421 ceph_fscache_readpage_cancel(inode, pages[i]); 422 unlock_page(pages[i]); 423 } 424 ceph_put_page_vector(pages, nr_pages, false); 425 out_put: 426 ceph_osdc_put_request(req); 427 out: 428 if (got) 429 ceph_put_cap_refs(ci, got); 430 return ret; 431 } 432 433 434 /* 435 * Read multiple pages. Leave pages we don't read + unlock in page_list; 436 * the caller (VM) cleans them up. 437 */ 438 static int ceph_readpages(struct file *file, struct address_space *mapping, 439 struct list_head *page_list, unsigned nr_pages) 440 { 441 struct inode *inode = file_inode(file); 442 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 443 int rc = 0; 444 int max = 0; 445 446 if (ceph_inode(inode)->i_inline_version != CEPH_INLINE_NONE) 447 return -EINVAL; 448 449 rc = ceph_readpages_from_fscache(mapping->host, mapping, page_list, 450 &nr_pages); 451 452 if (rc == 0) 453 goto out; 454 455 if (fsc->mount_options->rsize >= PAGE_SIZE) 456 max = (fsc->mount_options->rsize + PAGE_SIZE - 1) 457 >> PAGE_SHIFT; 458 459 dout("readpages %p file %p nr_pages %d max %d\n", inode, 460 file, nr_pages, 461 max); 462 while (!list_empty(page_list)) { 463 rc = start_read(inode, page_list, max); 464 if (rc < 0) 465 goto out; 466 } 467 out: 468 ceph_fscache_readpages_cancel(inode, page_list); 469 470 dout("readpages %p file %p ret %d\n", inode, file, rc); 471 return rc; 472 } 473 474 /* 475 * Get ref for the oldest snapc for an inode with dirty data... that is, the 476 * only snap context we are allowed to write back. 477 */ 478 static struct ceph_snap_context *get_oldest_context(struct inode *inode, 479 loff_t *snap_size, 480 u64 *truncate_size, 481 u32 *truncate_seq) 482 { 483 struct ceph_inode_info *ci = ceph_inode(inode); 484 struct ceph_snap_context *snapc = NULL; 485 struct ceph_cap_snap *capsnap = NULL; 486 487 spin_lock(&ci->i_ceph_lock); 488 list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) { 489 dout(" cap_snap %p snapc %p has %d dirty pages\n", capsnap, 490 capsnap->context, capsnap->dirty_pages); 491 if (capsnap->dirty_pages) { 492 snapc = ceph_get_snap_context(capsnap->context); 493 if (snap_size) 494 *snap_size = capsnap->size; 495 if (truncate_size) 496 *truncate_size = capsnap->truncate_size; 497 if (truncate_seq) 498 *truncate_seq = capsnap->truncate_seq; 499 break; 500 } 501 } 502 if (!snapc && ci->i_wrbuffer_ref_head) { 503 snapc = ceph_get_snap_context(ci->i_head_snapc); 504 dout(" head snapc %p has %d dirty pages\n", 505 snapc, ci->i_wrbuffer_ref_head); 506 if (truncate_size) 507 *truncate_size = ci->i_truncate_size; 508 if (truncate_seq) 509 *truncate_seq = ci->i_truncate_seq; 510 } 511 spin_unlock(&ci->i_ceph_lock); 512 return snapc; 513 } 514 515 /* 516 * Write a single page, but leave the page locked. 517 * 518 * If we get a write error, set the page error bit, but still adjust the 519 * dirty page accounting (i.e., page is no longer dirty). 520 */ 521 static int writepage_nounlock(struct page *page, struct writeback_control *wbc) 522 { 523 struct inode *inode; 524 struct ceph_inode_info *ci; 525 struct ceph_fs_client *fsc; 526 struct ceph_osd_client *osdc; 527 struct ceph_snap_context *snapc, *oldest; 528 loff_t page_off = page_offset(page); 529 loff_t snap_size = -1; 530 long writeback_stat; 531 u64 truncate_size; 532 u32 truncate_seq; 533 int err = 0, len = PAGE_SIZE; 534 535 dout("writepage %p idx %lu\n", page, page->index); 536 537 if (!page->mapping || !page->mapping->host) { 538 dout("writepage %p - no mapping\n", page); 539 return -EFAULT; 540 } 541 inode = page->mapping->host; 542 ci = ceph_inode(inode); 543 fsc = ceph_inode_to_client(inode); 544 osdc = &fsc->client->osdc; 545 546 /* verify this is a writeable snap context */ 547 snapc = page_snap_context(page); 548 if (snapc == NULL) { 549 dout("writepage %p page %p not dirty?\n", inode, page); 550 goto out; 551 } 552 oldest = get_oldest_context(inode, &snap_size, 553 &truncate_size, &truncate_seq); 554 if (snapc->seq > oldest->seq) { 555 dout("writepage %p page %p snapc %p not writeable - noop\n", 556 inode, page, snapc); 557 /* we should only noop if called by kswapd */ 558 WARN_ON((current->flags & PF_MEMALLOC) == 0); 559 ceph_put_snap_context(oldest); 560 goto out; 561 } 562 ceph_put_snap_context(oldest); 563 564 if (snap_size == -1) 565 snap_size = i_size_read(inode); 566 567 /* is this a partial page at end of file? */ 568 if (page_off >= snap_size) { 569 dout("%p page eof %llu\n", page, snap_size); 570 goto out; 571 } 572 if (snap_size < page_off + len) 573 len = snap_size - page_off; 574 575 dout("writepage %p page %p index %lu on %llu~%u snapc %p\n", 576 inode, page, page->index, page_off, len, snapc); 577 578 writeback_stat = atomic_long_inc_return(&fsc->writeback_count); 579 if (writeback_stat > 580 CONGESTION_ON_THRESH(fsc->mount_options->congestion_kb)) 581 set_bdi_congested(&fsc->backing_dev_info, BLK_RW_ASYNC); 582 583 set_page_writeback(page); 584 err = ceph_osdc_writepages(osdc, ceph_vino(inode), 585 &ci->i_layout, snapc, 586 page_off, len, 587 truncate_seq, truncate_size, 588 &inode->i_mtime, &page, 1); 589 if (err < 0) { 590 struct writeback_control tmp_wbc; 591 if (!wbc) 592 wbc = &tmp_wbc; 593 if (err == -ERESTARTSYS) { 594 /* killed by SIGKILL */ 595 dout("writepage interrupted page %p\n", page); 596 redirty_page_for_writepage(wbc, page); 597 end_page_writeback(page); 598 goto out; 599 } 600 dout("writepage setting page/mapping error %d %p\n", 601 err, page); 602 SetPageError(page); 603 mapping_set_error(&inode->i_data, err); 604 wbc->pages_skipped++; 605 } else { 606 dout("writepage cleaned page %p\n", page); 607 err = 0; /* vfs expects us to return 0 */ 608 } 609 page->private = 0; 610 ClearPagePrivate(page); 611 end_page_writeback(page); 612 ceph_put_wrbuffer_cap_refs(ci, 1, snapc); 613 ceph_put_snap_context(snapc); /* page's reference */ 614 out: 615 return err; 616 } 617 618 static int ceph_writepage(struct page *page, struct writeback_control *wbc) 619 { 620 int err; 621 struct inode *inode = page->mapping->host; 622 BUG_ON(!inode); 623 ihold(inode); 624 err = writepage_nounlock(page, wbc); 625 if (err == -ERESTARTSYS) { 626 /* direct memory reclaimer was killed by SIGKILL. return 0 627 * to prevent caller from setting mapping/page error */ 628 err = 0; 629 } 630 unlock_page(page); 631 iput(inode); 632 return err; 633 } 634 635 /* 636 * lame release_pages helper. release_pages() isn't exported to 637 * modules. 638 */ 639 static void ceph_release_pages(struct page **pages, int num) 640 { 641 struct pagevec pvec; 642 int i; 643 644 pagevec_init(&pvec, 0); 645 for (i = 0; i < num; i++) { 646 if (pagevec_add(&pvec, pages[i]) == 0) 647 pagevec_release(&pvec); 648 } 649 pagevec_release(&pvec); 650 } 651 652 /* 653 * async writeback completion handler. 654 * 655 * If we get an error, set the mapping error bit, but not the individual 656 * page error bits. 657 */ 658 static void writepages_finish(struct ceph_osd_request *req) 659 { 660 struct inode *inode = req->r_inode; 661 struct ceph_inode_info *ci = ceph_inode(inode); 662 struct ceph_osd_data *osd_data; 663 struct page *page; 664 int num_pages, total_pages = 0; 665 int i, j; 666 int rc = req->r_result; 667 struct ceph_snap_context *snapc = req->r_snapc; 668 struct address_space *mapping = inode->i_mapping; 669 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 670 bool remove_page; 671 672 dout("writepages_finish %p rc %d\n", inode, rc); 673 if (rc < 0) 674 mapping_set_error(mapping, rc); 675 676 /* 677 * We lost the cache cap, need to truncate the page before 678 * it is unlocked, otherwise we'd truncate it later in the 679 * page truncation thread, possibly losing some data that 680 * raced its way in 681 */ 682 remove_page = !(ceph_caps_issued(ci) & 683 (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)); 684 685 /* clean all pages */ 686 for (i = 0; i < req->r_num_ops; i++) { 687 if (req->r_ops[i].op != CEPH_OSD_OP_WRITE) 688 break; 689 690 osd_data = osd_req_op_extent_osd_data(req, i); 691 BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES); 692 num_pages = calc_pages_for((u64)osd_data->alignment, 693 (u64)osd_data->length); 694 total_pages += num_pages; 695 for (j = 0; j < num_pages; j++) { 696 page = osd_data->pages[j]; 697 BUG_ON(!page); 698 WARN_ON(!PageUptodate(page)); 699 700 if (atomic_long_dec_return(&fsc->writeback_count) < 701 CONGESTION_OFF_THRESH( 702 fsc->mount_options->congestion_kb)) 703 clear_bdi_congested(&fsc->backing_dev_info, 704 BLK_RW_ASYNC); 705 706 if (rc < 0) 707 SetPageError(page); 708 709 ceph_put_snap_context(page_snap_context(page)); 710 page->private = 0; 711 ClearPagePrivate(page); 712 dout("unlocking %p\n", page); 713 end_page_writeback(page); 714 715 if (remove_page) 716 generic_error_remove_page(inode->i_mapping, 717 page); 718 719 unlock_page(page); 720 } 721 dout("writepages_finish %p wrote %llu bytes cleaned %d pages\n", 722 inode, osd_data->length, rc >= 0 ? num_pages : 0); 723 724 ceph_release_pages(osd_data->pages, num_pages); 725 } 726 727 ceph_put_wrbuffer_cap_refs(ci, total_pages, snapc); 728 729 osd_data = osd_req_op_extent_osd_data(req, 0); 730 if (osd_data->pages_from_pool) 731 mempool_free(osd_data->pages, 732 ceph_sb_to_client(inode->i_sb)->wb_pagevec_pool); 733 else 734 kfree(osd_data->pages); 735 ceph_osdc_put_request(req); 736 } 737 738 /* 739 * initiate async writeback 740 */ 741 static int ceph_writepages_start(struct address_space *mapping, 742 struct writeback_control *wbc) 743 { 744 struct inode *inode = mapping->host; 745 struct ceph_inode_info *ci = ceph_inode(inode); 746 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 747 struct ceph_vino vino = ceph_vino(inode); 748 pgoff_t index, start, end; 749 int range_whole = 0; 750 int should_loop = 1; 751 pgoff_t max_pages = 0, max_pages_ever = 0; 752 struct ceph_snap_context *snapc = NULL, *last_snapc = NULL, *pgsnapc; 753 struct pagevec pvec; 754 int done = 0; 755 int rc = 0; 756 unsigned int wsize = i_blocksize(inode); 757 struct ceph_osd_request *req = NULL; 758 int do_sync = 0; 759 loff_t snap_size, i_size; 760 u64 truncate_size; 761 u32 truncate_seq; 762 763 /* 764 * Include a 'sync' in the OSD request if this is a data 765 * integrity write (e.g., O_SYNC write or fsync()), or if our 766 * cap is being revoked. 767 */ 768 if ((wbc->sync_mode == WB_SYNC_ALL) || 769 ceph_caps_revoking(ci, CEPH_CAP_FILE_BUFFER)) 770 do_sync = 1; 771 dout("writepages_start %p dosync=%d (mode=%s)\n", 772 inode, do_sync, 773 wbc->sync_mode == WB_SYNC_NONE ? "NONE" : 774 (wbc->sync_mode == WB_SYNC_ALL ? "ALL" : "HOLD")); 775 776 if (READ_ONCE(fsc->mount_state) == CEPH_MOUNT_SHUTDOWN) { 777 if (ci->i_wrbuffer_ref > 0) { 778 pr_warn_ratelimited( 779 "writepage_start %p %lld forced umount\n", 780 inode, ceph_ino(inode)); 781 } 782 mapping_set_error(mapping, -EIO); 783 return -EIO; /* we're in a forced umount, don't write! */ 784 } 785 if (fsc->mount_options->wsize && fsc->mount_options->wsize < wsize) 786 wsize = fsc->mount_options->wsize; 787 if (wsize < PAGE_SIZE) 788 wsize = PAGE_SIZE; 789 max_pages_ever = wsize >> PAGE_SHIFT; 790 791 pagevec_init(&pvec, 0); 792 793 /* where to start/end? */ 794 if (wbc->range_cyclic) { 795 start = mapping->writeback_index; /* Start from prev offset */ 796 end = -1; 797 dout(" cyclic, start at %lu\n", start); 798 } else { 799 start = wbc->range_start >> PAGE_SHIFT; 800 end = wbc->range_end >> PAGE_SHIFT; 801 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) 802 range_whole = 1; 803 should_loop = 0; 804 dout(" not cyclic, %lu to %lu\n", start, end); 805 } 806 index = start; 807 808 retry: 809 /* find oldest snap context with dirty data */ 810 ceph_put_snap_context(snapc); 811 snap_size = -1; 812 snapc = get_oldest_context(inode, &snap_size, 813 &truncate_size, &truncate_seq); 814 if (!snapc) { 815 /* hmm, why does writepages get called when there 816 is no dirty data? */ 817 dout(" no snap context with dirty data?\n"); 818 goto out; 819 } 820 dout(" oldest snapc is %p seq %lld (%d snaps)\n", 821 snapc, snapc->seq, snapc->num_snaps); 822 823 i_size = i_size_read(inode); 824 825 if (last_snapc && snapc != last_snapc) { 826 /* if we switched to a newer snapc, restart our scan at the 827 * start of the original file range. */ 828 dout(" snapc differs from last pass, restarting at %lu\n", 829 index); 830 index = start; 831 } 832 last_snapc = snapc; 833 834 while (!done && index <= end) { 835 unsigned i; 836 int first; 837 pgoff_t strip_unit_end = 0; 838 int num_ops = 0, op_idx; 839 int pvec_pages, locked_pages = 0; 840 struct page **pages = NULL, **data_pages; 841 mempool_t *pool = NULL; /* Becomes non-null if mempool used */ 842 struct page *page; 843 int want; 844 u64 offset = 0, len = 0; 845 846 max_pages = max_pages_ever; 847 848 get_more_pages: 849 first = -1; 850 want = min(end - index, 851 min((pgoff_t)PAGEVEC_SIZE, 852 max_pages - (pgoff_t)locked_pages) - 1) 853 + 1; 854 pvec_pages = pagevec_lookup_tag(&pvec, mapping, &index, 855 PAGECACHE_TAG_DIRTY, 856 want); 857 dout("pagevec_lookup_tag got %d\n", pvec_pages); 858 if (!pvec_pages && !locked_pages) 859 break; 860 for (i = 0; i < pvec_pages && locked_pages < max_pages; i++) { 861 page = pvec.pages[i]; 862 dout("? %p idx %lu\n", page, page->index); 863 if (locked_pages == 0) 864 lock_page(page); /* first page */ 865 else if (!trylock_page(page)) 866 break; 867 868 /* only dirty pages, or our accounting breaks */ 869 if (unlikely(!PageDirty(page)) || 870 unlikely(page->mapping != mapping)) { 871 dout("!dirty or !mapping %p\n", page); 872 unlock_page(page); 873 break; 874 } 875 if (!wbc->range_cyclic && page->index > end) { 876 dout("end of range %p\n", page); 877 done = 1; 878 unlock_page(page); 879 break; 880 } 881 if (strip_unit_end && (page->index > strip_unit_end)) { 882 dout("end of strip unit %p\n", page); 883 unlock_page(page); 884 break; 885 } 886 if (wbc->sync_mode != WB_SYNC_NONE) { 887 dout("waiting on writeback %p\n", page); 888 wait_on_page_writeback(page); 889 } 890 if (page_offset(page) >= 891 (snap_size == -1 ? i_size : snap_size)) { 892 dout("%p page eof %llu\n", page, 893 (snap_size == -1 ? i_size : snap_size)); 894 done = 1; 895 unlock_page(page); 896 break; 897 } 898 if (PageWriteback(page)) { 899 dout("%p under writeback\n", page); 900 unlock_page(page); 901 break; 902 } 903 904 /* only if matching snap context */ 905 pgsnapc = page_snap_context(page); 906 if (pgsnapc->seq > snapc->seq) { 907 dout("page snapc %p %lld > oldest %p %lld\n", 908 pgsnapc, pgsnapc->seq, snapc, snapc->seq); 909 unlock_page(page); 910 if (!locked_pages) 911 continue; /* keep looking for snap */ 912 break; 913 } 914 915 if (!clear_page_dirty_for_io(page)) { 916 dout("%p !clear_page_dirty_for_io\n", page); 917 unlock_page(page); 918 break; 919 } 920 921 /* 922 * We have something to write. If this is 923 * the first locked page this time through, 924 * calculate max possinle write size and 925 * allocate a page array 926 */ 927 if (locked_pages == 0) { 928 u64 objnum; 929 u64 objoff; 930 931 /* prepare async write request */ 932 offset = (u64)page_offset(page); 933 len = wsize; 934 935 rc = ceph_calc_file_object_mapping(&ci->i_layout, 936 offset, len, 937 &objnum, &objoff, 938 &len); 939 if (rc < 0) { 940 unlock_page(page); 941 break; 942 } 943 944 num_ops = 1 + do_sync; 945 strip_unit_end = page->index + 946 ((len - 1) >> PAGE_SHIFT); 947 948 BUG_ON(pages); 949 max_pages = calc_pages_for(0, (u64)len); 950 pages = kmalloc(max_pages * sizeof (*pages), 951 GFP_NOFS); 952 if (!pages) { 953 pool = fsc->wb_pagevec_pool; 954 pages = mempool_alloc(pool, GFP_NOFS); 955 BUG_ON(!pages); 956 } 957 958 len = 0; 959 } else if (page->index != 960 (offset + len) >> PAGE_SHIFT) { 961 if (num_ops >= (pool ? CEPH_OSD_SLAB_OPS : 962 CEPH_OSD_MAX_OPS)) { 963 redirty_page_for_writepage(wbc, page); 964 unlock_page(page); 965 break; 966 } 967 968 num_ops++; 969 offset = (u64)page_offset(page); 970 len = 0; 971 } 972 973 /* note position of first page in pvec */ 974 if (first < 0) 975 first = i; 976 dout("%p will write page %p idx %lu\n", 977 inode, page, page->index); 978 979 if (atomic_long_inc_return(&fsc->writeback_count) > 980 CONGESTION_ON_THRESH( 981 fsc->mount_options->congestion_kb)) { 982 set_bdi_congested(&fsc->backing_dev_info, 983 BLK_RW_ASYNC); 984 } 985 986 pages[locked_pages] = page; 987 locked_pages++; 988 len += PAGE_SIZE; 989 } 990 991 /* did we get anything? */ 992 if (!locked_pages) 993 goto release_pvec_pages; 994 if (i) { 995 int j; 996 BUG_ON(!locked_pages || first < 0); 997 998 if (pvec_pages && i == pvec_pages && 999 locked_pages < max_pages) { 1000 dout("reached end pvec, trying for more\n"); 1001 pagevec_reinit(&pvec); 1002 goto get_more_pages; 1003 } 1004 1005 /* shift unused pages over in the pvec... we 1006 * will need to release them below. */ 1007 for (j = i; j < pvec_pages; j++) { 1008 dout(" pvec leftover page %p\n", pvec.pages[j]); 1009 pvec.pages[j-i+first] = pvec.pages[j]; 1010 } 1011 pvec.nr -= i-first; 1012 } 1013 1014 new_request: 1015 offset = page_offset(pages[0]); 1016 len = wsize; 1017 1018 req = ceph_osdc_new_request(&fsc->client->osdc, 1019 &ci->i_layout, vino, 1020 offset, &len, 0, num_ops, 1021 CEPH_OSD_OP_WRITE, 1022 CEPH_OSD_FLAG_WRITE, 1023 snapc, truncate_seq, 1024 truncate_size, false); 1025 if (IS_ERR(req)) { 1026 req = ceph_osdc_new_request(&fsc->client->osdc, 1027 &ci->i_layout, vino, 1028 offset, &len, 0, 1029 min(num_ops, 1030 CEPH_OSD_SLAB_OPS), 1031 CEPH_OSD_OP_WRITE, 1032 CEPH_OSD_FLAG_WRITE, 1033 snapc, truncate_seq, 1034 truncate_size, true); 1035 BUG_ON(IS_ERR(req)); 1036 } 1037 BUG_ON(len < page_offset(pages[locked_pages - 1]) + 1038 PAGE_SIZE - offset); 1039 1040 req->r_callback = writepages_finish; 1041 req->r_inode = inode; 1042 1043 /* Format the osd request message and submit the write */ 1044 len = 0; 1045 data_pages = pages; 1046 op_idx = 0; 1047 for (i = 0; i < locked_pages; i++) { 1048 u64 cur_offset = page_offset(pages[i]); 1049 if (offset + len != cur_offset) { 1050 if (op_idx + do_sync + 1 == req->r_num_ops) 1051 break; 1052 osd_req_op_extent_dup_last(req, op_idx, 1053 cur_offset - offset); 1054 dout("writepages got pages at %llu~%llu\n", 1055 offset, len); 1056 osd_req_op_extent_osd_data_pages(req, op_idx, 1057 data_pages, len, 0, 1058 !!pool, false); 1059 osd_req_op_extent_update(req, op_idx, len); 1060 1061 len = 0; 1062 offset = cur_offset; 1063 data_pages = pages + i; 1064 op_idx++; 1065 } 1066 1067 set_page_writeback(pages[i]); 1068 len += PAGE_SIZE; 1069 } 1070 1071 if (snap_size != -1) { 1072 len = min(len, snap_size - offset); 1073 } else if (i == locked_pages) { 1074 /* writepages_finish() clears writeback pages 1075 * according to the data length, so make sure 1076 * data length covers all locked pages */ 1077 u64 min_len = len + 1 - PAGE_SIZE; 1078 len = min(len, (u64)i_size_read(inode) - offset); 1079 len = max(len, min_len); 1080 } 1081 dout("writepages got pages at %llu~%llu\n", offset, len); 1082 1083 osd_req_op_extent_osd_data_pages(req, op_idx, data_pages, len, 1084 0, !!pool, false); 1085 osd_req_op_extent_update(req, op_idx, len); 1086 1087 if (do_sync) { 1088 op_idx++; 1089 osd_req_op_init(req, op_idx, CEPH_OSD_OP_STARTSYNC, 0); 1090 } 1091 BUG_ON(op_idx + 1 != req->r_num_ops); 1092 1093 pool = NULL; 1094 if (i < locked_pages) { 1095 BUG_ON(num_ops <= req->r_num_ops); 1096 num_ops -= req->r_num_ops; 1097 num_ops += do_sync; 1098 locked_pages -= i; 1099 1100 /* allocate new pages array for next request */ 1101 data_pages = pages; 1102 pages = kmalloc(locked_pages * sizeof (*pages), 1103 GFP_NOFS); 1104 if (!pages) { 1105 pool = fsc->wb_pagevec_pool; 1106 pages = mempool_alloc(pool, GFP_NOFS); 1107 BUG_ON(!pages); 1108 } 1109 memcpy(pages, data_pages + i, 1110 locked_pages * sizeof(*pages)); 1111 memset(data_pages + i, 0, 1112 locked_pages * sizeof(*pages)); 1113 } else { 1114 BUG_ON(num_ops != req->r_num_ops); 1115 index = pages[i - 1]->index + 1; 1116 /* request message now owns the pages array */ 1117 pages = NULL; 1118 } 1119 1120 req->r_mtime = inode->i_mtime; 1121 rc = ceph_osdc_start_request(&fsc->client->osdc, req, true); 1122 BUG_ON(rc); 1123 req = NULL; 1124 1125 wbc->nr_to_write -= i; 1126 if (pages) 1127 goto new_request; 1128 1129 if (wbc->nr_to_write <= 0) 1130 done = 1; 1131 1132 release_pvec_pages: 1133 dout("pagevec_release on %d pages (%p)\n", (int)pvec.nr, 1134 pvec.nr ? pvec.pages[0] : NULL); 1135 pagevec_release(&pvec); 1136 1137 if (locked_pages && !done) 1138 goto retry; 1139 } 1140 1141 if (should_loop && !done) { 1142 /* more to do; loop back to beginning of file */ 1143 dout("writepages looping back to beginning of file\n"); 1144 should_loop = 0; 1145 index = 0; 1146 goto retry; 1147 } 1148 1149 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0)) 1150 mapping->writeback_index = index; 1151 1152 out: 1153 ceph_osdc_put_request(req); 1154 ceph_put_snap_context(snapc); 1155 dout("writepages done, rc = %d\n", rc); 1156 return rc; 1157 } 1158 1159 1160 1161 /* 1162 * See if a given @snapc is either writeable, or already written. 1163 */ 1164 static int context_is_writeable_or_written(struct inode *inode, 1165 struct ceph_snap_context *snapc) 1166 { 1167 struct ceph_snap_context *oldest = get_oldest_context(inode, NULL, 1168 NULL, NULL); 1169 int ret = !oldest || snapc->seq <= oldest->seq; 1170 1171 ceph_put_snap_context(oldest); 1172 return ret; 1173 } 1174 1175 /* 1176 * We are only allowed to write into/dirty the page if the page is 1177 * clean, or already dirty within the same snap context. 1178 * 1179 * called with page locked. 1180 * return success with page locked, 1181 * or any failure (incl -EAGAIN) with page unlocked. 1182 */ 1183 static int ceph_update_writeable_page(struct file *file, 1184 loff_t pos, unsigned len, 1185 struct page *page) 1186 { 1187 struct inode *inode = file_inode(file); 1188 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 1189 struct ceph_inode_info *ci = ceph_inode(inode); 1190 loff_t page_off = pos & PAGE_MASK; 1191 int pos_in_page = pos & ~PAGE_MASK; 1192 int end_in_page = pos_in_page + len; 1193 loff_t i_size; 1194 int r; 1195 struct ceph_snap_context *snapc, *oldest; 1196 1197 if (READ_ONCE(fsc->mount_state) == CEPH_MOUNT_SHUTDOWN) { 1198 dout(" page %p forced umount\n", page); 1199 unlock_page(page); 1200 return -EIO; 1201 } 1202 1203 retry_locked: 1204 /* writepages currently holds page lock, but if we change that later, */ 1205 wait_on_page_writeback(page); 1206 1207 snapc = page_snap_context(page); 1208 if (snapc && snapc != ci->i_head_snapc) { 1209 /* 1210 * this page is already dirty in another (older) snap 1211 * context! is it writeable now? 1212 */ 1213 oldest = get_oldest_context(inode, NULL, NULL, NULL); 1214 1215 if (snapc->seq > oldest->seq) { 1216 ceph_put_snap_context(oldest); 1217 dout(" page %p snapc %p not current or oldest\n", 1218 page, snapc); 1219 /* 1220 * queue for writeback, and wait for snapc to 1221 * be writeable or written 1222 */ 1223 snapc = ceph_get_snap_context(snapc); 1224 unlock_page(page); 1225 ceph_queue_writeback(inode); 1226 r = wait_event_killable(ci->i_cap_wq, 1227 context_is_writeable_or_written(inode, snapc)); 1228 ceph_put_snap_context(snapc); 1229 if (r == -ERESTARTSYS) 1230 return r; 1231 return -EAGAIN; 1232 } 1233 ceph_put_snap_context(oldest); 1234 1235 /* yay, writeable, do it now (without dropping page lock) */ 1236 dout(" page %p snapc %p not current, but oldest\n", 1237 page, snapc); 1238 if (!clear_page_dirty_for_io(page)) 1239 goto retry_locked; 1240 r = writepage_nounlock(page, NULL); 1241 if (r < 0) 1242 goto fail_nosnap; 1243 goto retry_locked; 1244 } 1245 1246 if (PageUptodate(page)) { 1247 dout(" page %p already uptodate\n", page); 1248 return 0; 1249 } 1250 1251 /* full page? */ 1252 if (pos_in_page == 0 && len == PAGE_SIZE) 1253 return 0; 1254 1255 /* past end of file? */ 1256 i_size = i_size_read(inode); 1257 1258 if (page_off >= i_size || 1259 (pos_in_page == 0 && (pos+len) >= i_size && 1260 end_in_page - pos_in_page != PAGE_SIZE)) { 1261 dout(" zeroing %p 0 - %d and %d - %d\n", 1262 page, pos_in_page, end_in_page, (int)PAGE_SIZE); 1263 zero_user_segments(page, 1264 0, pos_in_page, 1265 end_in_page, PAGE_SIZE); 1266 return 0; 1267 } 1268 1269 /* we need to read it. */ 1270 r = readpage_nounlock(file, page); 1271 if (r < 0) 1272 goto fail_nosnap; 1273 goto retry_locked; 1274 fail_nosnap: 1275 unlock_page(page); 1276 return r; 1277 } 1278 1279 /* 1280 * We are only allowed to write into/dirty the page if the page is 1281 * clean, or already dirty within the same snap context. 1282 */ 1283 static int ceph_write_begin(struct file *file, struct address_space *mapping, 1284 loff_t pos, unsigned len, unsigned flags, 1285 struct page **pagep, void **fsdata) 1286 { 1287 struct inode *inode = file_inode(file); 1288 struct page *page; 1289 pgoff_t index = pos >> PAGE_SHIFT; 1290 int r; 1291 1292 do { 1293 /* get a page */ 1294 page = grab_cache_page_write_begin(mapping, index, 0); 1295 if (!page) 1296 return -ENOMEM; 1297 1298 dout("write_begin file %p inode %p page %p %d~%d\n", file, 1299 inode, page, (int)pos, (int)len); 1300 1301 r = ceph_update_writeable_page(file, pos, len, page); 1302 if (r < 0) 1303 put_page(page); 1304 else 1305 *pagep = page; 1306 } while (r == -EAGAIN); 1307 1308 return r; 1309 } 1310 1311 /* 1312 * we don't do anything in here that simple_write_end doesn't do 1313 * except adjust dirty page accounting 1314 */ 1315 static int ceph_write_end(struct file *file, struct address_space *mapping, 1316 loff_t pos, unsigned len, unsigned copied, 1317 struct page *page, void *fsdata) 1318 { 1319 struct inode *inode = file_inode(file); 1320 int check_cap = 0; 1321 1322 dout("write_end file %p inode %p page %p %d~%d (%d)\n", file, 1323 inode, page, (int)pos, (int)copied, (int)len); 1324 1325 /* zero the stale part of the page if we did a short copy */ 1326 if (!PageUptodate(page)) { 1327 if (copied < len) { 1328 copied = 0; 1329 goto out; 1330 } 1331 SetPageUptodate(page); 1332 } 1333 1334 /* did file size increase? */ 1335 if (pos+copied > i_size_read(inode)) 1336 check_cap = ceph_inode_set_size(inode, pos+copied); 1337 1338 set_page_dirty(page); 1339 1340 out: 1341 unlock_page(page); 1342 put_page(page); 1343 1344 if (check_cap) 1345 ceph_check_caps(ceph_inode(inode), CHECK_CAPS_AUTHONLY, NULL); 1346 1347 return copied; 1348 } 1349 1350 /* 1351 * we set .direct_IO to indicate direct io is supported, but since we 1352 * intercept O_DIRECT reads and writes early, this function should 1353 * never get called. 1354 */ 1355 static ssize_t ceph_direct_io(struct kiocb *iocb, struct iov_iter *iter) 1356 { 1357 WARN_ON(1); 1358 return -EINVAL; 1359 } 1360 1361 const struct address_space_operations ceph_aops = { 1362 .readpage = ceph_readpage, 1363 .readpages = ceph_readpages, 1364 .writepage = ceph_writepage, 1365 .writepages = ceph_writepages_start, 1366 .write_begin = ceph_write_begin, 1367 .write_end = ceph_write_end, 1368 .set_page_dirty = ceph_set_page_dirty, 1369 .invalidatepage = ceph_invalidatepage, 1370 .releasepage = ceph_releasepage, 1371 .direct_IO = ceph_direct_io, 1372 }; 1373 1374 static void ceph_block_sigs(sigset_t *oldset) 1375 { 1376 sigset_t mask; 1377 siginitsetinv(&mask, sigmask(SIGKILL)); 1378 sigprocmask(SIG_BLOCK, &mask, oldset); 1379 } 1380 1381 static void ceph_restore_sigs(sigset_t *oldset) 1382 { 1383 sigprocmask(SIG_SETMASK, oldset, NULL); 1384 } 1385 1386 /* 1387 * vm ops 1388 */ 1389 static int ceph_filemap_fault(struct vm_fault *vmf) 1390 { 1391 struct vm_area_struct *vma = vmf->vma; 1392 struct inode *inode = file_inode(vma->vm_file); 1393 struct ceph_inode_info *ci = ceph_inode(inode); 1394 struct ceph_file_info *fi = vma->vm_file->private_data; 1395 struct page *pinned_page = NULL; 1396 loff_t off = vmf->pgoff << PAGE_SHIFT; 1397 int want, got, ret; 1398 sigset_t oldset; 1399 1400 ceph_block_sigs(&oldset); 1401 1402 dout("filemap_fault %p %llx.%llx %llu~%zd trying to get caps\n", 1403 inode, ceph_vinop(inode), off, (size_t)PAGE_SIZE); 1404 if (fi->fmode & CEPH_FILE_MODE_LAZY) 1405 want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO; 1406 else 1407 want = CEPH_CAP_FILE_CACHE; 1408 1409 got = 0; 1410 ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, -1, &got, &pinned_page); 1411 if (ret < 0) 1412 goto out_restore; 1413 1414 dout("filemap_fault %p %llu~%zd got cap refs on %s\n", 1415 inode, off, (size_t)PAGE_SIZE, ceph_cap_string(got)); 1416 1417 if ((got & (CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO)) || 1418 ci->i_inline_version == CEPH_INLINE_NONE) { 1419 current->journal_info = vma->vm_file; 1420 ret = filemap_fault(vmf); 1421 current->journal_info = NULL; 1422 } else 1423 ret = -EAGAIN; 1424 1425 dout("filemap_fault %p %llu~%zd dropping cap refs on %s ret %d\n", 1426 inode, off, (size_t)PAGE_SIZE, ceph_cap_string(got), ret); 1427 if (pinned_page) 1428 put_page(pinned_page); 1429 ceph_put_cap_refs(ci, got); 1430 1431 if (ret != -EAGAIN) 1432 goto out_restore; 1433 1434 /* read inline data */ 1435 if (off >= PAGE_SIZE) { 1436 /* does not support inline data > PAGE_SIZE */ 1437 ret = VM_FAULT_SIGBUS; 1438 } else { 1439 int ret1; 1440 struct address_space *mapping = inode->i_mapping; 1441 struct page *page = find_or_create_page(mapping, 0, 1442 mapping_gfp_constraint(mapping, 1443 ~__GFP_FS)); 1444 if (!page) { 1445 ret = VM_FAULT_OOM; 1446 goto out_inline; 1447 } 1448 ret1 = __ceph_do_getattr(inode, page, 1449 CEPH_STAT_CAP_INLINE_DATA, true); 1450 if (ret1 < 0 || off >= i_size_read(inode)) { 1451 unlock_page(page); 1452 put_page(page); 1453 if (ret1 < 0) 1454 ret = ret1; 1455 else 1456 ret = VM_FAULT_SIGBUS; 1457 goto out_inline; 1458 } 1459 if (ret1 < PAGE_SIZE) 1460 zero_user_segment(page, ret1, PAGE_SIZE); 1461 else 1462 flush_dcache_page(page); 1463 SetPageUptodate(page); 1464 vmf->page = page; 1465 ret = VM_FAULT_MAJOR | VM_FAULT_LOCKED; 1466 out_inline: 1467 dout("filemap_fault %p %llu~%zd read inline data ret %d\n", 1468 inode, off, (size_t)PAGE_SIZE, ret); 1469 } 1470 out_restore: 1471 ceph_restore_sigs(&oldset); 1472 if (ret < 0) 1473 ret = (ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS; 1474 1475 return ret; 1476 } 1477 1478 /* 1479 * Reuse write_begin here for simplicity. 1480 */ 1481 static int ceph_page_mkwrite(struct vm_fault *vmf) 1482 { 1483 struct vm_area_struct *vma = vmf->vma; 1484 struct inode *inode = file_inode(vma->vm_file); 1485 struct ceph_inode_info *ci = ceph_inode(inode); 1486 struct ceph_file_info *fi = vma->vm_file->private_data; 1487 struct ceph_cap_flush *prealloc_cf; 1488 struct page *page = vmf->page; 1489 loff_t off = page_offset(page); 1490 loff_t size = i_size_read(inode); 1491 size_t len; 1492 int want, got, ret; 1493 sigset_t oldset; 1494 1495 prealloc_cf = ceph_alloc_cap_flush(); 1496 if (!prealloc_cf) 1497 return VM_FAULT_OOM; 1498 1499 ceph_block_sigs(&oldset); 1500 1501 if (ci->i_inline_version != CEPH_INLINE_NONE) { 1502 struct page *locked_page = NULL; 1503 if (off == 0) { 1504 lock_page(page); 1505 locked_page = page; 1506 } 1507 ret = ceph_uninline_data(vma->vm_file, locked_page); 1508 if (locked_page) 1509 unlock_page(locked_page); 1510 if (ret < 0) 1511 goto out_free; 1512 } 1513 1514 if (off + PAGE_SIZE <= size) 1515 len = PAGE_SIZE; 1516 else 1517 len = size & ~PAGE_MASK; 1518 1519 dout("page_mkwrite %p %llx.%llx %llu~%zd getting caps i_size %llu\n", 1520 inode, ceph_vinop(inode), off, len, size); 1521 if (fi->fmode & CEPH_FILE_MODE_LAZY) 1522 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO; 1523 else 1524 want = CEPH_CAP_FILE_BUFFER; 1525 1526 got = 0; 1527 ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, off + len, 1528 &got, NULL); 1529 if (ret < 0) 1530 goto out_free; 1531 1532 dout("page_mkwrite %p %llu~%zd got cap refs on %s\n", 1533 inode, off, len, ceph_cap_string(got)); 1534 1535 /* Update time before taking page lock */ 1536 file_update_time(vma->vm_file); 1537 1538 do { 1539 lock_page(page); 1540 1541 if ((off > size) || (page->mapping != inode->i_mapping)) { 1542 unlock_page(page); 1543 ret = VM_FAULT_NOPAGE; 1544 break; 1545 } 1546 1547 ret = ceph_update_writeable_page(vma->vm_file, off, len, page); 1548 if (ret >= 0) { 1549 /* success. we'll keep the page locked. */ 1550 set_page_dirty(page); 1551 ret = VM_FAULT_LOCKED; 1552 } 1553 } while (ret == -EAGAIN); 1554 1555 if (ret == VM_FAULT_LOCKED || 1556 ci->i_inline_version != CEPH_INLINE_NONE) { 1557 int dirty; 1558 spin_lock(&ci->i_ceph_lock); 1559 ci->i_inline_version = CEPH_INLINE_NONE; 1560 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR, 1561 &prealloc_cf); 1562 spin_unlock(&ci->i_ceph_lock); 1563 if (dirty) 1564 __mark_inode_dirty(inode, dirty); 1565 } 1566 1567 dout("page_mkwrite %p %llu~%zd dropping cap refs on %s ret %d\n", 1568 inode, off, len, ceph_cap_string(got), ret); 1569 ceph_put_cap_refs(ci, got); 1570 out_free: 1571 ceph_restore_sigs(&oldset); 1572 ceph_free_cap_flush(prealloc_cf); 1573 if (ret < 0) 1574 ret = (ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS; 1575 return ret; 1576 } 1577 1578 void ceph_fill_inline_data(struct inode *inode, struct page *locked_page, 1579 char *data, size_t len) 1580 { 1581 struct address_space *mapping = inode->i_mapping; 1582 struct page *page; 1583 1584 if (locked_page) { 1585 page = locked_page; 1586 } else { 1587 if (i_size_read(inode) == 0) 1588 return; 1589 page = find_or_create_page(mapping, 0, 1590 mapping_gfp_constraint(mapping, 1591 ~__GFP_FS)); 1592 if (!page) 1593 return; 1594 if (PageUptodate(page)) { 1595 unlock_page(page); 1596 put_page(page); 1597 return; 1598 } 1599 } 1600 1601 dout("fill_inline_data %p %llx.%llx len %zu locked_page %p\n", 1602 inode, ceph_vinop(inode), len, locked_page); 1603 1604 if (len > 0) { 1605 void *kaddr = kmap_atomic(page); 1606 memcpy(kaddr, data, len); 1607 kunmap_atomic(kaddr); 1608 } 1609 1610 if (page != locked_page) { 1611 if (len < PAGE_SIZE) 1612 zero_user_segment(page, len, PAGE_SIZE); 1613 else 1614 flush_dcache_page(page); 1615 1616 SetPageUptodate(page); 1617 unlock_page(page); 1618 put_page(page); 1619 } 1620 } 1621 1622 int ceph_uninline_data(struct file *filp, struct page *locked_page) 1623 { 1624 struct inode *inode = file_inode(filp); 1625 struct ceph_inode_info *ci = ceph_inode(inode); 1626 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 1627 struct ceph_osd_request *req; 1628 struct page *page = NULL; 1629 u64 len, inline_version; 1630 int err = 0; 1631 bool from_pagecache = false; 1632 1633 spin_lock(&ci->i_ceph_lock); 1634 inline_version = ci->i_inline_version; 1635 spin_unlock(&ci->i_ceph_lock); 1636 1637 dout("uninline_data %p %llx.%llx inline_version %llu\n", 1638 inode, ceph_vinop(inode), inline_version); 1639 1640 if (inline_version == 1 || /* initial version, no data */ 1641 inline_version == CEPH_INLINE_NONE) 1642 goto out; 1643 1644 if (locked_page) { 1645 page = locked_page; 1646 WARN_ON(!PageUptodate(page)); 1647 } else if (ceph_caps_issued(ci) & 1648 (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) { 1649 page = find_get_page(inode->i_mapping, 0); 1650 if (page) { 1651 if (PageUptodate(page)) { 1652 from_pagecache = true; 1653 lock_page(page); 1654 } else { 1655 put_page(page); 1656 page = NULL; 1657 } 1658 } 1659 } 1660 1661 if (page) { 1662 len = i_size_read(inode); 1663 if (len > PAGE_SIZE) 1664 len = PAGE_SIZE; 1665 } else { 1666 page = __page_cache_alloc(GFP_NOFS); 1667 if (!page) { 1668 err = -ENOMEM; 1669 goto out; 1670 } 1671 err = __ceph_do_getattr(inode, page, 1672 CEPH_STAT_CAP_INLINE_DATA, true); 1673 if (err < 0) { 1674 /* no inline data */ 1675 if (err == -ENODATA) 1676 err = 0; 1677 goto out; 1678 } 1679 len = err; 1680 } 1681 1682 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout, 1683 ceph_vino(inode), 0, &len, 0, 1, 1684 CEPH_OSD_OP_CREATE, CEPH_OSD_FLAG_WRITE, 1685 NULL, 0, 0, false); 1686 if (IS_ERR(req)) { 1687 err = PTR_ERR(req); 1688 goto out; 1689 } 1690 1691 req->r_mtime = inode->i_mtime; 1692 err = ceph_osdc_start_request(&fsc->client->osdc, req, false); 1693 if (!err) 1694 err = ceph_osdc_wait_request(&fsc->client->osdc, req); 1695 ceph_osdc_put_request(req); 1696 if (err < 0) 1697 goto out; 1698 1699 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout, 1700 ceph_vino(inode), 0, &len, 1, 3, 1701 CEPH_OSD_OP_WRITE, CEPH_OSD_FLAG_WRITE, 1702 NULL, ci->i_truncate_seq, 1703 ci->i_truncate_size, false); 1704 if (IS_ERR(req)) { 1705 err = PTR_ERR(req); 1706 goto out; 1707 } 1708 1709 osd_req_op_extent_osd_data_pages(req, 1, &page, len, 0, false, false); 1710 1711 { 1712 __le64 xattr_buf = cpu_to_le64(inline_version); 1713 err = osd_req_op_xattr_init(req, 0, CEPH_OSD_OP_CMPXATTR, 1714 "inline_version", &xattr_buf, 1715 sizeof(xattr_buf), 1716 CEPH_OSD_CMPXATTR_OP_GT, 1717 CEPH_OSD_CMPXATTR_MODE_U64); 1718 if (err) 1719 goto out_put; 1720 } 1721 1722 { 1723 char xattr_buf[32]; 1724 int xattr_len = snprintf(xattr_buf, sizeof(xattr_buf), 1725 "%llu", inline_version); 1726 err = osd_req_op_xattr_init(req, 2, CEPH_OSD_OP_SETXATTR, 1727 "inline_version", 1728 xattr_buf, xattr_len, 0, 0); 1729 if (err) 1730 goto out_put; 1731 } 1732 1733 req->r_mtime = inode->i_mtime; 1734 err = ceph_osdc_start_request(&fsc->client->osdc, req, false); 1735 if (!err) 1736 err = ceph_osdc_wait_request(&fsc->client->osdc, req); 1737 out_put: 1738 ceph_osdc_put_request(req); 1739 if (err == -ECANCELED) 1740 err = 0; 1741 out: 1742 if (page && page != locked_page) { 1743 if (from_pagecache) { 1744 unlock_page(page); 1745 put_page(page); 1746 } else 1747 __free_pages(page, 0); 1748 } 1749 1750 dout("uninline_data %p %llx.%llx inline_version %llu = %d\n", 1751 inode, ceph_vinop(inode), inline_version, err); 1752 return err; 1753 } 1754 1755 static const struct vm_operations_struct ceph_vmops = { 1756 .fault = ceph_filemap_fault, 1757 .page_mkwrite = ceph_page_mkwrite, 1758 }; 1759 1760 int ceph_mmap(struct file *file, struct vm_area_struct *vma) 1761 { 1762 struct address_space *mapping = file->f_mapping; 1763 1764 if (!mapping->a_ops->readpage) 1765 return -ENOEXEC; 1766 file_accessed(file); 1767 vma->vm_ops = &ceph_vmops; 1768 return 0; 1769 } 1770 1771 enum { 1772 POOL_READ = 1, 1773 POOL_WRITE = 2, 1774 }; 1775 1776 static int __ceph_pool_perm_get(struct ceph_inode_info *ci, 1777 s64 pool, struct ceph_string *pool_ns) 1778 { 1779 struct ceph_fs_client *fsc = ceph_inode_to_client(&ci->vfs_inode); 1780 struct ceph_mds_client *mdsc = fsc->mdsc; 1781 struct ceph_osd_request *rd_req = NULL, *wr_req = NULL; 1782 struct rb_node **p, *parent; 1783 struct ceph_pool_perm *perm; 1784 struct page **pages; 1785 size_t pool_ns_len; 1786 int err = 0, err2 = 0, have = 0; 1787 1788 down_read(&mdsc->pool_perm_rwsem); 1789 p = &mdsc->pool_perm_tree.rb_node; 1790 while (*p) { 1791 perm = rb_entry(*p, struct ceph_pool_perm, node); 1792 if (pool < perm->pool) 1793 p = &(*p)->rb_left; 1794 else if (pool > perm->pool) 1795 p = &(*p)->rb_right; 1796 else { 1797 int ret = ceph_compare_string(pool_ns, 1798 perm->pool_ns, 1799 perm->pool_ns_len); 1800 if (ret < 0) 1801 p = &(*p)->rb_left; 1802 else if (ret > 0) 1803 p = &(*p)->rb_right; 1804 else { 1805 have = perm->perm; 1806 break; 1807 } 1808 } 1809 } 1810 up_read(&mdsc->pool_perm_rwsem); 1811 if (*p) 1812 goto out; 1813 1814 if (pool_ns) 1815 dout("__ceph_pool_perm_get pool %lld ns %.*s no perm cached\n", 1816 pool, (int)pool_ns->len, pool_ns->str); 1817 else 1818 dout("__ceph_pool_perm_get pool %lld no perm cached\n", pool); 1819 1820 down_write(&mdsc->pool_perm_rwsem); 1821 p = &mdsc->pool_perm_tree.rb_node; 1822 parent = NULL; 1823 while (*p) { 1824 parent = *p; 1825 perm = rb_entry(parent, struct ceph_pool_perm, node); 1826 if (pool < perm->pool) 1827 p = &(*p)->rb_left; 1828 else if (pool > perm->pool) 1829 p = &(*p)->rb_right; 1830 else { 1831 int ret = ceph_compare_string(pool_ns, 1832 perm->pool_ns, 1833 perm->pool_ns_len); 1834 if (ret < 0) 1835 p = &(*p)->rb_left; 1836 else if (ret > 0) 1837 p = &(*p)->rb_right; 1838 else { 1839 have = perm->perm; 1840 break; 1841 } 1842 } 1843 } 1844 if (*p) { 1845 up_write(&mdsc->pool_perm_rwsem); 1846 goto out; 1847 } 1848 1849 rd_req = ceph_osdc_alloc_request(&fsc->client->osdc, NULL, 1850 1, false, GFP_NOFS); 1851 if (!rd_req) { 1852 err = -ENOMEM; 1853 goto out_unlock; 1854 } 1855 1856 rd_req->r_flags = CEPH_OSD_FLAG_READ; 1857 osd_req_op_init(rd_req, 0, CEPH_OSD_OP_STAT, 0); 1858 rd_req->r_base_oloc.pool = pool; 1859 if (pool_ns) 1860 rd_req->r_base_oloc.pool_ns = ceph_get_string(pool_ns); 1861 ceph_oid_printf(&rd_req->r_base_oid, "%llx.00000000", ci->i_vino.ino); 1862 1863 err = ceph_osdc_alloc_messages(rd_req, GFP_NOFS); 1864 if (err) 1865 goto out_unlock; 1866 1867 wr_req = ceph_osdc_alloc_request(&fsc->client->osdc, NULL, 1868 1, false, GFP_NOFS); 1869 if (!wr_req) { 1870 err = -ENOMEM; 1871 goto out_unlock; 1872 } 1873 1874 wr_req->r_flags = CEPH_OSD_FLAG_WRITE; 1875 osd_req_op_init(wr_req, 0, CEPH_OSD_OP_CREATE, CEPH_OSD_OP_FLAG_EXCL); 1876 ceph_oloc_copy(&wr_req->r_base_oloc, &rd_req->r_base_oloc); 1877 ceph_oid_copy(&wr_req->r_base_oid, &rd_req->r_base_oid); 1878 1879 err = ceph_osdc_alloc_messages(wr_req, GFP_NOFS); 1880 if (err) 1881 goto out_unlock; 1882 1883 /* one page should be large enough for STAT data */ 1884 pages = ceph_alloc_page_vector(1, GFP_KERNEL); 1885 if (IS_ERR(pages)) { 1886 err = PTR_ERR(pages); 1887 goto out_unlock; 1888 } 1889 1890 osd_req_op_raw_data_in_pages(rd_req, 0, pages, PAGE_SIZE, 1891 0, false, true); 1892 err = ceph_osdc_start_request(&fsc->client->osdc, rd_req, false); 1893 1894 wr_req->r_mtime = ci->vfs_inode.i_mtime; 1895 err2 = ceph_osdc_start_request(&fsc->client->osdc, wr_req, false); 1896 1897 if (!err) 1898 err = ceph_osdc_wait_request(&fsc->client->osdc, rd_req); 1899 if (!err2) 1900 err2 = ceph_osdc_wait_request(&fsc->client->osdc, wr_req); 1901 1902 if (err >= 0 || err == -ENOENT) 1903 have |= POOL_READ; 1904 else if (err != -EPERM) 1905 goto out_unlock; 1906 1907 if (err2 == 0 || err2 == -EEXIST) 1908 have |= POOL_WRITE; 1909 else if (err2 != -EPERM) { 1910 err = err2; 1911 goto out_unlock; 1912 } 1913 1914 pool_ns_len = pool_ns ? pool_ns->len : 0; 1915 perm = kmalloc(sizeof(*perm) + pool_ns_len + 1, GFP_NOFS); 1916 if (!perm) { 1917 err = -ENOMEM; 1918 goto out_unlock; 1919 } 1920 1921 perm->pool = pool; 1922 perm->perm = have; 1923 perm->pool_ns_len = pool_ns_len; 1924 if (pool_ns_len > 0) 1925 memcpy(perm->pool_ns, pool_ns->str, pool_ns_len); 1926 perm->pool_ns[pool_ns_len] = 0; 1927 1928 rb_link_node(&perm->node, parent, p); 1929 rb_insert_color(&perm->node, &mdsc->pool_perm_tree); 1930 err = 0; 1931 out_unlock: 1932 up_write(&mdsc->pool_perm_rwsem); 1933 1934 ceph_osdc_put_request(rd_req); 1935 ceph_osdc_put_request(wr_req); 1936 out: 1937 if (!err) 1938 err = have; 1939 if (pool_ns) 1940 dout("__ceph_pool_perm_get pool %lld ns %.*s result = %d\n", 1941 pool, (int)pool_ns->len, pool_ns->str, err); 1942 else 1943 dout("__ceph_pool_perm_get pool %lld result = %d\n", pool, err); 1944 return err; 1945 } 1946 1947 int ceph_pool_perm_check(struct ceph_inode_info *ci, int need) 1948 { 1949 s64 pool; 1950 struct ceph_string *pool_ns; 1951 int ret, flags; 1952 1953 if (ci->i_vino.snap != CEPH_NOSNAP) { 1954 /* 1955 * Pool permission check needs to write to the first object. 1956 * But for snapshot, head of the first object may have alread 1957 * been deleted. Skip check to avoid creating orphan object. 1958 */ 1959 return 0; 1960 } 1961 1962 if (ceph_test_mount_opt(ceph_inode_to_client(&ci->vfs_inode), 1963 NOPOOLPERM)) 1964 return 0; 1965 1966 spin_lock(&ci->i_ceph_lock); 1967 flags = ci->i_ceph_flags; 1968 pool = ci->i_layout.pool_id; 1969 spin_unlock(&ci->i_ceph_lock); 1970 check: 1971 if (flags & CEPH_I_POOL_PERM) { 1972 if ((need & CEPH_CAP_FILE_RD) && !(flags & CEPH_I_POOL_RD)) { 1973 dout("ceph_pool_perm_check pool %lld no read perm\n", 1974 pool); 1975 return -EPERM; 1976 } 1977 if ((need & CEPH_CAP_FILE_WR) && !(flags & CEPH_I_POOL_WR)) { 1978 dout("ceph_pool_perm_check pool %lld no write perm\n", 1979 pool); 1980 return -EPERM; 1981 } 1982 return 0; 1983 } 1984 1985 pool_ns = ceph_try_get_string(ci->i_layout.pool_ns); 1986 ret = __ceph_pool_perm_get(ci, pool, pool_ns); 1987 ceph_put_string(pool_ns); 1988 if (ret < 0) 1989 return ret; 1990 1991 flags = CEPH_I_POOL_PERM; 1992 if (ret & POOL_READ) 1993 flags |= CEPH_I_POOL_RD; 1994 if (ret & POOL_WRITE) 1995 flags |= CEPH_I_POOL_WR; 1996 1997 spin_lock(&ci->i_ceph_lock); 1998 if (pool == ci->i_layout.pool_id && 1999 pool_ns == rcu_dereference_raw(ci->i_layout.pool_ns)) { 2000 ci->i_ceph_flags |= flags; 2001 } else { 2002 pool = ci->i_layout.pool_id; 2003 flags = ci->i_ceph_flags; 2004 } 2005 spin_unlock(&ci->i_ceph_lock); 2006 goto check; 2007 } 2008 2009 void ceph_pool_perm_destroy(struct ceph_mds_client *mdsc) 2010 { 2011 struct ceph_pool_perm *perm; 2012 struct rb_node *n; 2013 2014 while (!RB_EMPTY_ROOT(&mdsc->pool_perm_tree)) { 2015 n = rb_first(&mdsc->pool_perm_tree); 2016 perm = rb_entry(n, struct ceph_pool_perm, node); 2017 rb_erase(n, &mdsc->pool_perm_tree); 2018 kfree(perm); 2019 } 2020 } 2021