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 WARN_ON(!PageLocked(page)); 156 if (!PagePrivate(page)) 157 return; 158 159 ClearPageChecked(page); 160 161 dout("%p invalidatepage %p idx %lu full dirty page\n", 162 inode, page, page->index); 163 164 ceph_put_wrbuffer_cap_refs(ci, 1, snapc); 165 ceph_put_snap_context(snapc); 166 page->private = 0; 167 ClearPagePrivate(page); 168 } 169 170 static int ceph_releasepage(struct page *page, gfp_t g) 171 { 172 dout("%p releasepage %p idx %lu (%sdirty)\n", page->mapping->host, 173 page, page->index, PageDirty(page) ? "" : "not "); 174 175 /* Can we release the page from the cache? */ 176 if (!ceph_release_fscache_page(page, g)) 177 return 0; 178 179 return !PagePrivate(page); 180 } 181 182 /* 183 * read a single page, without unlocking it. 184 */ 185 static int ceph_do_readpage(struct file *filp, struct page *page) 186 { 187 struct inode *inode = file_inode(filp); 188 struct ceph_inode_info *ci = ceph_inode(inode); 189 struct ceph_osd_client *osdc = 190 &ceph_inode_to_client(inode)->client->osdc; 191 int err = 0; 192 u64 off = page_offset(page); 193 u64 len = PAGE_SIZE; 194 195 if (off >= i_size_read(inode)) { 196 zero_user_segment(page, 0, PAGE_SIZE); 197 SetPageUptodate(page); 198 return 0; 199 } 200 201 if (ci->i_inline_version != CEPH_INLINE_NONE) { 202 /* 203 * Uptodate inline data should have been added 204 * into page cache while getting Fcr caps. 205 */ 206 if (off == 0) 207 return -EINVAL; 208 zero_user_segment(page, 0, PAGE_SIZE); 209 SetPageUptodate(page); 210 return 0; 211 } 212 213 err = ceph_readpage_from_fscache(inode, page); 214 if (err == 0) 215 return -EINPROGRESS; 216 217 dout("readpage inode %p file %p page %p index %lu\n", 218 inode, filp, page, page->index); 219 err = ceph_osdc_readpages(osdc, ceph_vino(inode), &ci->i_layout, 220 off, &len, 221 ci->i_truncate_seq, ci->i_truncate_size, 222 &page, 1, 0); 223 if (err == -ENOENT) 224 err = 0; 225 if (err < 0) { 226 SetPageError(page); 227 ceph_fscache_readpage_cancel(inode, page); 228 goto out; 229 } 230 if (err < PAGE_SIZE) 231 /* zero fill remainder of page */ 232 zero_user_segment(page, err, PAGE_SIZE); 233 else 234 flush_dcache_page(page); 235 236 SetPageUptodate(page); 237 ceph_readpage_to_fscache(inode, page); 238 239 out: 240 return err < 0 ? err : 0; 241 } 242 243 static int ceph_readpage(struct file *filp, struct page *page) 244 { 245 int r = ceph_do_readpage(filp, page); 246 if (r != -EINPROGRESS) 247 unlock_page(page); 248 else 249 r = 0; 250 return r; 251 } 252 253 /* 254 * Finish an async read(ahead) op. 255 */ 256 static void finish_read(struct ceph_osd_request *req) 257 { 258 struct inode *inode = req->r_inode; 259 struct ceph_osd_data *osd_data; 260 int rc = req->r_result <= 0 ? req->r_result : 0; 261 int bytes = req->r_result >= 0 ? req->r_result : 0; 262 int num_pages; 263 int i; 264 265 dout("finish_read %p req %p rc %d bytes %d\n", inode, req, rc, bytes); 266 267 /* unlock all pages, zeroing any data we didn't read */ 268 osd_data = osd_req_op_extent_osd_data(req, 0); 269 BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES); 270 num_pages = calc_pages_for((u64)osd_data->alignment, 271 (u64)osd_data->length); 272 for (i = 0; i < num_pages; i++) { 273 struct page *page = osd_data->pages[i]; 274 275 if (rc < 0 && rc != -ENOENT) { 276 ceph_fscache_readpage_cancel(inode, page); 277 goto unlock; 278 } 279 if (bytes < (int)PAGE_SIZE) { 280 /* zero (remainder of) page */ 281 int s = bytes < 0 ? 0 : bytes; 282 zero_user_segment(page, s, PAGE_SIZE); 283 } 284 dout("finish_read %p uptodate %p idx %lu\n", inode, page, 285 page->index); 286 flush_dcache_page(page); 287 SetPageUptodate(page); 288 ceph_readpage_to_fscache(inode, page); 289 unlock: 290 unlock_page(page); 291 put_page(page); 292 bytes -= PAGE_SIZE; 293 } 294 kfree(osd_data->pages); 295 } 296 297 /* 298 * start an async read(ahead) operation. return nr_pages we submitted 299 * a read for on success, or negative error code. 300 */ 301 static int start_read(struct inode *inode, struct list_head *page_list, int max) 302 { 303 struct ceph_osd_client *osdc = 304 &ceph_inode_to_client(inode)->client->osdc; 305 struct ceph_inode_info *ci = ceph_inode(inode); 306 struct page *page = list_entry(page_list->prev, struct page, lru); 307 struct ceph_vino vino; 308 struct ceph_osd_request *req; 309 u64 off; 310 u64 len; 311 int i; 312 struct page **pages; 313 pgoff_t next_index; 314 int nr_pages = 0; 315 int got = 0; 316 int ret = 0; 317 318 if (!current->journal_info) { 319 /* caller of readpages does not hold buffer and read caps 320 * (fadvise, madvise and readahead cases) */ 321 int want = CEPH_CAP_FILE_CACHE; 322 ret = ceph_try_get_caps(ci, CEPH_CAP_FILE_RD, want, &got); 323 if (ret < 0) { 324 dout("start_read %p, error getting cap\n", inode); 325 } else if (!(got & want)) { 326 dout("start_read %p, no cache cap\n", inode); 327 ret = 0; 328 } 329 if (ret <= 0) { 330 if (got) 331 ceph_put_cap_refs(ci, got); 332 while (!list_empty(page_list)) { 333 page = list_entry(page_list->prev, 334 struct page, lru); 335 list_del(&page->lru); 336 put_page(page); 337 } 338 return ret; 339 } 340 } 341 342 off = (u64) page_offset(page); 343 344 /* count pages */ 345 next_index = page->index; 346 list_for_each_entry_reverse(page, page_list, lru) { 347 if (page->index != next_index) 348 break; 349 nr_pages++; 350 next_index++; 351 if (max && nr_pages == max) 352 break; 353 } 354 len = nr_pages << PAGE_SHIFT; 355 dout("start_read %p nr_pages %d is %lld~%lld\n", inode, nr_pages, 356 off, len); 357 vino = ceph_vino(inode); 358 req = ceph_osdc_new_request(osdc, &ci->i_layout, vino, off, &len, 359 0, 1, CEPH_OSD_OP_READ, 360 CEPH_OSD_FLAG_READ, NULL, 361 ci->i_truncate_seq, ci->i_truncate_size, 362 false); 363 if (IS_ERR(req)) { 364 ret = PTR_ERR(req); 365 goto out; 366 } 367 368 /* build page vector */ 369 nr_pages = calc_pages_for(0, len); 370 pages = kmalloc(sizeof(*pages) * nr_pages, GFP_KERNEL); 371 if (!pages) { 372 ret = -ENOMEM; 373 goto out_put; 374 } 375 for (i = 0; i < nr_pages; ++i) { 376 page = list_entry(page_list->prev, struct page, lru); 377 BUG_ON(PageLocked(page)); 378 list_del(&page->lru); 379 380 dout("start_read %p adding %p idx %lu\n", inode, page, 381 page->index); 382 if (add_to_page_cache_lru(page, &inode->i_data, page->index, 383 GFP_KERNEL)) { 384 ceph_fscache_uncache_page(inode, page); 385 put_page(page); 386 dout("start_read %p add_to_page_cache failed %p\n", 387 inode, page); 388 nr_pages = i; 389 if (nr_pages > 0) { 390 len = nr_pages << PAGE_SHIFT; 391 osd_req_op_extent_update(req, 0, len); 392 break; 393 } 394 goto out_pages; 395 } 396 pages[i] = page; 397 } 398 osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0, false, false); 399 req->r_callback = finish_read; 400 req->r_inode = inode; 401 402 dout("start_read %p starting %p %lld~%lld\n", inode, req, off, len); 403 ret = ceph_osdc_start_request(osdc, req, false); 404 if (ret < 0) 405 goto out_pages; 406 ceph_osdc_put_request(req); 407 408 /* After adding locked pages to page cache, the inode holds cache cap. 409 * So we can drop our cap refs. */ 410 if (got) 411 ceph_put_cap_refs(ci, got); 412 413 return nr_pages; 414 415 out_pages: 416 for (i = 0; i < nr_pages; ++i) { 417 ceph_fscache_readpage_cancel(inode, pages[i]); 418 unlock_page(pages[i]); 419 } 420 ceph_put_page_vector(pages, nr_pages, false); 421 out_put: 422 ceph_osdc_put_request(req); 423 out: 424 if (got) 425 ceph_put_cap_refs(ci, got); 426 return ret; 427 } 428 429 430 /* 431 * Read multiple pages. Leave pages we don't read + unlock in page_list; 432 * the caller (VM) cleans them up. 433 */ 434 static int ceph_readpages(struct file *file, struct address_space *mapping, 435 struct list_head *page_list, unsigned nr_pages) 436 { 437 struct inode *inode = file_inode(file); 438 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 439 int rc = 0; 440 int max = 0; 441 442 if (ceph_inode(inode)->i_inline_version != CEPH_INLINE_NONE) 443 return -EINVAL; 444 445 rc = ceph_readpages_from_fscache(mapping->host, mapping, page_list, 446 &nr_pages); 447 448 if (rc == 0) 449 goto out; 450 451 max = fsc->mount_options->rsize >> PAGE_SHIFT; 452 dout("readpages %p file %p nr_pages %d max %d\n", 453 inode, file, nr_pages, max); 454 while (!list_empty(page_list)) { 455 rc = start_read(inode, page_list, max); 456 if (rc < 0) 457 goto out; 458 } 459 out: 460 ceph_fscache_readpages_cancel(inode, page_list); 461 462 dout("readpages %p file %p ret %d\n", inode, file, rc); 463 return rc; 464 } 465 466 struct ceph_writeback_ctl 467 { 468 loff_t i_size; 469 u64 truncate_size; 470 u32 truncate_seq; 471 bool size_stable; 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 * 479 get_oldest_context(struct inode *inode, struct ceph_writeback_ctl *ctl, 480 struct ceph_snap_context *page_snapc) 481 { 482 struct ceph_inode_info *ci = ceph_inode(inode); 483 struct ceph_snap_context *snapc = NULL; 484 struct ceph_cap_snap *capsnap = NULL; 485 486 spin_lock(&ci->i_ceph_lock); 487 list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) { 488 dout(" cap_snap %p snapc %p has %d dirty pages\n", capsnap, 489 capsnap->context, capsnap->dirty_pages); 490 if (!capsnap->dirty_pages) 491 continue; 492 493 /* get i_size, truncate_{seq,size} for page_snapc? */ 494 if (snapc && capsnap->context != page_snapc) 495 continue; 496 497 if (ctl) { 498 if (capsnap->writing) { 499 ctl->i_size = i_size_read(inode); 500 ctl->size_stable = false; 501 } else { 502 ctl->i_size = capsnap->size; 503 ctl->size_stable = true; 504 } 505 ctl->truncate_size = capsnap->truncate_size; 506 ctl->truncate_seq = capsnap->truncate_seq; 507 } 508 509 if (snapc) 510 break; 511 512 snapc = ceph_get_snap_context(capsnap->context); 513 if (!page_snapc || 514 page_snapc == snapc || 515 page_snapc->seq > snapc->seq) 516 break; 517 } 518 if (!snapc && ci->i_wrbuffer_ref_head) { 519 snapc = ceph_get_snap_context(ci->i_head_snapc); 520 dout(" head snapc %p has %d dirty pages\n", 521 snapc, ci->i_wrbuffer_ref_head); 522 if (ctl) { 523 ctl->i_size = i_size_read(inode); 524 ctl->truncate_size = ci->i_truncate_size; 525 ctl->truncate_seq = ci->i_truncate_seq; 526 ctl->size_stable = false; 527 } 528 } 529 spin_unlock(&ci->i_ceph_lock); 530 return snapc; 531 } 532 533 static u64 get_writepages_data_length(struct inode *inode, 534 struct page *page, u64 start) 535 { 536 struct ceph_inode_info *ci = ceph_inode(inode); 537 struct ceph_snap_context *snapc = page_snap_context(page); 538 struct ceph_cap_snap *capsnap = NULL; 539 u64 end = i_size_read(inode); 540 541 if (snapc != ci->i_head_snapc) { 542 bool found = false; 543 spin_lock(&ci->i_ceph_lock); 544 list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) { 545 if (capsnap->context == snapc) { 546 if (!capsnap->writing) 547 end = capsnap->size; 548 found = true; 549 break; 550 } 551 } 552 spin_unlock(&ci->i_ceph_lock); 553 WARN_ON(!found); 554 } 555 if (end > page_offset(page) + PAGE_SIZE) 556 end = page_offset(page) + PAGE_SIZE; 557 return end > start ? end - start : 0; 558 } 559 560 /* 561 * Write a single page, but leave the page locked. 562 * 563 * If we get a write error, set the page error bit, but still adjust the 564 * dirty page accounting (i.e., page is no longer dirty). 565 */ 566 static int writepage_nounlock(struct page *page, struct writeback_control *wbc) 567 { 568 struct inode *inode; 569 struct ceph_inode_info *ci; 570 struct ceph_fs_client *fsc; 571 struct ceph_snap_context *snapc, *oldest; 572 loff_t page_off = page_offset(page); 573 long writeback_stat; 574 int err, len = PAGE_SIZE; 575 struct ceph_writeback_ctl ceph_wbc; 576 577 dout("writepage %p idx %lu\n", page, page->index); 578 579 inode = page->mapping->host; 580 ci = ceph_inode(inode); 581 fsc = ceph_inode_to_client(inode); 582 583 /* verify this is a writeable snap context */ 584 snapc = page_snap_context(page); 585 if (!snapc) { 586 dout("writepage %p page %p not dirty?\n", inode, page); 587 return 0; 588 } 589 oldest = get_oldest_context(inode, &ceph_wbc, snapc); 590 if (snapc->seq > oldest->seq) { 591 dout("writepage %p page %p snapc %p not writeable - noop\n", 592 inode, page, snapc); 593 /* we should only noop if called by kswapd */ 594 WARN_ON(!(current->flags & PF_MEMALLOC)); 595 ceph_put_snap_context(oldest); 596 redirty_page_for_writepage(wbc, page); 597 return 0; 598 } 599 ceph_put_snap_context(oldest); 600 601 /* is this a partial page at end of file? */ 602 if (page_off >= ceph_wbc.i_size) { 603 dout("%p page eof %llu\n", page, ceph_wbc.i_size); 604 page->mapping->a_ops->invalidatepage(page, 0, PAGE_SIZE); 605 return 0; 606 } 607 608 if (ceph_wbc.i_size < page_off + len) 609 len = ceph_wbc.i_size - page_off; 610 611 dout("writepage %p page %p index %lu on %llu~%u snapc %p seq %lld\n", 612 inode, page, page->index, page_off, len, snapc, snapc->seq); 613 614 writeback_stat = atomic_long_inc_return(&fsc->writeback_count); 615 if (writeback_stat > 616 CONGESTION_ON_THRESH(fsc->mount_options->congestion_kb)) 617 set_bdi_congested(inode_to_bdi(inode), BLK_RW_ASYNC); 618 619 set_page_writeback(page); 620 err = ceph_osdc_writepages(&fsc->client->osdc, ceph_vino(inode), 621 &ci->i_layout, snapc, page_off, len, 622 ceph_wbc.truncate_seq, 623 ceph_wbc.truncate_size, 624 &inode->i_mtime, &page, 1); 625 if (err < 0) { 626 struct writeback_control tmp_wbc; 627 if (!wbc) 628 wbc = &tmp_wbc; 629 if (err == -ERESTARTSYS) { 630 /* killed by SIGKILL */ 631 dout("writepage interrupted page %p\n", page); 632 redirty_page_for_writepage(wbc, page); 633 end_page_writeback(page); 634 return err; 635 } 636 dout("writepage setting page/mapping error %d %p\n", 637 err, page); 638 SetPageError(page); 639 mapping_set_error(&inode->i_data, err); 640 wbc->pages_skipped++; 641 } else { 642 dout("writepage cleaned page %p\n", page); 643 err = 0; /* vfs expects us to return 0 */ 644 } 645 page->private = 0; 646 ClearPagePrivate(page); 647 end_page_writeback(page); 648 ceph_put_wrbuffer_cap_refs(ci, 1, snapc); 649 ceph_put_snap_context(snapc); /* page's reference */ 650 return err; 651 } 652 653 static int ceph_writepage(struct page *page, struct writeback_control *wbc) 654 { 655 int err; 656 struct inode *inode = page->mapping->host; 657 BUG_ON(!inode); 658 ihold(inode); 659 err = writepage_nounlock(page, wbc); 660 if (err == -ERESTARTSYS) { 661 /* direct memory reclaimer was killed by SIGKILL. return 0 662 * to prevent caller from setting mapping/page error */ 663 err = 0; 664 } 665 unlock_page(page); 666 iput(inode); 667 return err; 668 } 669 670 /* 671 * lame release_pages helper. release_pages() isn't exported to 672 * modules. 673 */ 674 static void ceph_release_pages(struct page **pages, int num) 675 { 676 struct pagevec pvec; 677 int i; 678 679 pagevec_init(&pvec, 0); 680 for (i = 0; i < num; i++) { 681 if (pagevec_add(&pvec, pages[i]) == 0) 682 pagevec_release(&pvec); 683 } 684 pagevec_release(&pvec); 685 } 686 687 /* 688 * async writeback completion handler. 689 * 690 * If we get an error, set the mapping error bit, but not the individual 691 * page error bits. 692 */ 693 static void writepages_finish(struct ceph_osd_request *req) 694 { 695 struct inode *inode = req->r_inode; 696 struct ceph_inode_info *ci = ceph_inode(inode); 697 struct ceph_osd_data *osd_data; 698 struct page *page; 699 int num_pages, total_pages = 0; 700 int i, j; 701 int rc = req->r_result; 702 struct ceph_snap_context *snapc = req->r_snapc; 703 struct address_space *mapping = inode->i_mapping; 704 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 705 bool remove_page; 706 707 dout("writepages_finish %p rc %d\n", inode, rc); 708 if (rc < 0) { 709 mapping_set_error(mapping, rc); 710 ceph_set_error_write(ci); 711 } else { 712 ceph_clear_error_write(ci); 713 } 714 715 /* 716 * We lost the cache cap, need to truncate the page before 717 * it is unlocked, otherwise we'd truncate it later in the 718 * page truncation thread, possibly losing some data that 719 * raced its way in 720 */ 721 remove_page = !(ceph_caps_issued(ci) & 722 (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)); 723 724 /* clean all pages */ 725 for (i = 0; i < req->r_num_ops; i++) { 726 if (req->r_ops[i].op != CEPH_OSD_OP_WRITE) 727 break; 728 729 osd_data = osd_req_op_extent_osd_data(req, i); 730 BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES); 731 num_pages = calc_pages_for((u64)osd_data->alignment, 732 (u64)osd_data->length); 733 total_pages += num_pages; 734 for (j = 0; j < num_pages; j++) { 735 page = osd_data->pages[j]; 736 BUG_ON(!page); 737 WARN_ON(!PageUptodate(page)); 738 739 if (atomic_long_dec_return(&fsc->writeback_count) < 740 CONGESTION_OFF_THRESH( 741 fsc->mount_options->congestion_kb)) 742 clear_bdi_congested(inode_to_bdi(inode), 743 BLK_RW_ASYNC); 744 745 ceph_put_snap_context(page_snap_context(page)); 746 page->private = 0; 747 ClearPagePrivate(page); 748 dout("unlocking %p\n", page); 749 end_page_writeback(page); 750 751 if (remove_page) 752 generic_error_remove_page(inode->i_mapping, 753 page); 754 755 unlock_page(page); 756 } 757 dout("writepages_finish %p wrote %llu bytes cleaned %d pages\n", 758 inode, osd_data->length, rc >= 0 ? num_pages : 0); 759 760 ceph_release_pages(osd_data->pages, num_pages); 761 } 762 763 ceph_put_wrbuffer_cap_refs(ci, total_pages, snapc); 764 765 osd_data = osd_req_op_extent_osd_data(req, 0); 766 if (osd_data->pages_from_pool) 767 mempool_free(osd_data->pages, 768 ceph_sb_to_client(inode->i_sb)->wb_pagevec_pool); 769 else 770 kfree(osd_data->pages); 771 ceph_osdc_put_request(req); 772 } 773 774 /* 775 * initiate async writeback 776 */ 777 static int ceph_writepages_start(struct address_space *mapping, 778 struct writeback_control *wbc) 779 { 780 struct inode *inode = mapping->host; 781 struct ceph_inode_info *ci = ceph_inode(inode); 782 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 783 struct ceph_vino vino = ceph_vino(inode); 784 pgoff_t index, start, end; 785 int range_whole = 0; 786 int should_loop = 1; 787 struct ceph_snap_context *snapc = NULL, *last_snapc = NULL, *pgsnapc; 788 struct pagevec pvec; 789 int done = 0; 790 int rc = 0; 791 unsigned int wsize = i_blocksize(inode); 792 struct ceph_osd_request *req = NULL; 793 struct ceph_writeback_ctl ceph_wbc; 794 795 dout("writepages_start %p (mode=%s)\n", inode, 796 wbc->sync_mode == WB_SYNC_NONE ? "NONE" : 797 (wbc->sync_mode == WB_SYNC_ALL ? "ALL" : "HOLD")); 798 799 if (READ_ONCE(fsc->mount_state) == CEPH_MOUNT_SHUTDOWN) { 800 if (ci->i_wrbuffer_ref > 0) { 801 pr_warn_ratelimited( 802 "writepage_start %p %lld forced umount\n", 803 inode, ceph_ino(inode)); 804 } 805 mapping_set_error(mapping, -EIO); 806 return -EIO; /* we're in a forced umount, don't write! */ 807 } 808 if (fsc->mount_options->wsize < wsize) 809 wsize = fsc->mount_options->wsize; 810 811 pagevec_init(&pvec, 0); 812 813 /* where to start/end? */ 814 if (wbc->range_cyclic) { 815 start = mapping->writeback_index; /* Start from prev offset */ 816 end = -1; 817 dout(" cyclic, start at %lu\n", start); 818 } else { 819 start = wbc->range_start >> PAGE_SHIFT; 820 end = wbc->range_end >> PAGE_SHIFT; 821 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) 822 range_whole = 1; 823 should_loop = 0; 824 dout(" not cyclic, %lu to %lu\n", start, end); 825 } 826 index = start; 827 828 retry: 829 /* find oldest snap context with dirty data */ 830 ceph_put_snap_context(snapc); 831 snapc = get_oldest_context(inode, &ceph_wbc, NULL); 832 if (!snapc) { 833 /* hmm, why does writepages get called when there 834 is no dirty data? */ 835 dout(" no snap context with dirty data?\n"); 836 goto out; 837 } 838 dout(" oldest snapc is %p seq %lld (%d snaps)\n", 839 snapc, snapc->seq, snapc->num_snaps); 840 841 if (last_snapc && snapc != last_snapc) { 842 /* if we switched to a newer snapc, restart our scan at the 843 * start of the original file range. */ 844 dout(" snapc differs from last pass, restarting at %lu\n", 845 index); 846 index = start; 847 } 848 last_snapc = snapc; 849 850 while (!done && index <= end) { 851 int num_ops = 0, op_idx; 852 unsigned i, pvec_pages, max_pages, locked_pages = 0; 853 struct page **pages = NULL, **data_pages; 854 mempool_t *pool = NULL; /* Becomes non-null if mempool used */ 855 struct page *page; 856 pgoff_t strip_unit_end = 0; 857 u64 offset = 0, len = 0; 858 859 max_pages = wsize >> PAGE_SHIFT; 860 861 get_more_pages: 862 pvec_pages = min_t(unsigned, PAGEVEC_SIZE, 863 max_pages - locked_pages); 864 if (end - index < (u64)(pvec_pages - 1)) 865 pvec_pages = (unsigned)(end - index) + 1; 866 867 pvec_pages = pagevec_lookup_tag(&pvec, mapping, &index, 868 PAGECACHE_TAG_DIRTY, 869 pvec_pages); 870 dout("pagevec_lookup_tag got %d\n", pvec_pages); 871 if (!pvec_pages && !locked_pages) 872 break; 873 for (i = 0; i < pvec_pages && locked_pages < max_pages; i++) { 874 page = pvec.pages[i]; 875 dout("? %p idx %lu\n", page, page->index); 876 if (locked_pages == 0) 877 lock_page(page); /* first page */ 878 else if (!trylock_page(page)) 879 break; 880 881 /* only dirty pages, or our accounting breaks */ 882 if (unlikely(!PageDirty(page)) || 883 unlikely(page->mapping != mapping)) { 884 dout("!dirty or !mapping %p\n", page); 885 unlock_page(page); 886 continue; 887 } 888 if (!wbc->range_cyclic && page->index > end) { 889 dout("end of range %p\n", page); 890 done = 1; 891 unlock_page(page); 892 break; 893 } 894 if (strip_unit_end && (page->index > strip_unit_end)) { 895 dout("end of strip unit %p\n", page); 896 unlock_page(page); 897 break; 898 } 899 if (page_offset(page) >= ceph_wbc.i_size) { 900 dout("%p page eof %llu\n", 901 page, ceph_wbc.i_size); 902 done = 1; 903 unlock_page(page); 904 break; 905 } 906 if (PageWriteback(page)) { 907 if (wbc->sync_mode == WB_SYNC_NONE) { 908 dout("%p under writeback\n", page); 909 unlock_page(page); 910 continue; 911 } 912 dout("waiting on writeback %p\n", page); 913 wait_on_page_writeback(page); 914 } 915 916 /* only if matching snap context */ 917 pgsnapc = page_snap_context(page); 918 if (pgsnapc->seq > snapc->seq) { 919 dout("page snapc %p %lld > oldest %p %lld\n", 920 pgsnapc, pgsnapc->seq, snapc, snapc->seq); 921 unlock_page(page); 922 continue; 923 } 924 925 if (!clear_page_dirty_for_io(page)) { 926 dout("%p !clear_page_dirty_for_io\n", page); 927 unlock_page(page); 928 continue; 929 } 930 931 /* 932 * We have something to write. If this is 933 * the first locked page this time through, 934 * calculate max possinle write size and 935 * allocate a page array 936 */ 937 if (locked_pages == 0) { 938 u64 objnum; 939 u64 objoff; 940 941 /* prepare async write request */ 942 offset = (u64)page_offset(page); 943 len = wsize; 944 945 rc = ceph_calc_file_object_mapping(&ci->i_layout, 946 offset, len, 947 &objnum, &objoff, 948 &len); 949 if (rc < 0) { 950 unlock_page(page); 951 break; 952 } 953 954 num_ops = 1; 955 strip_unit_end = page->index + 956 ((len - 1) >> PAGE_SHIFT); 957 958 BUG_ON(pages); 959 max_pages = calc_pages_for(0, (u64)len); 960 pages = kmalloc(max_pages * sizeof (*pages), 961 GFP_NOFS); 962 if (!pages) { 963 pool = fsc->wb_pagevec_pool; 964 pages = mempool_alloc(pool, GFP_NOFS); 965 BUG_ON(!pages); 966 } 967 968 len = 0; 969 } else if (page->index != 970 (offset + len) >> PAGE_SHIFT) { 971 if (num_ops >= (pool ? CEPH_OSD_SLAB_OPS : 972 CEPH_OSD_MAX_OPS)) { 973 redirty_page_for_writepage(wbc, page); 974 unlock_page(page); 975 break; 976 } 977 978 num_ops++; 979 offset = (u64)page_offset(page); 980 len = 0; 981 } 982 983 /* note position of first page in pvec */ 984 dout("%p will write page %p idx %lu\n", 985 inode, page, page->index); 986 987 if (atomic_long_inc_return(&fsc->writeback_count) > 988 CONGESTION_ON_THRESH( 989 fsc->mount_options->congestion_kb)) { 990 set_bdi_congested(inode_to_bdi(inode), 991 BLK_RW_ASYNC); 992 } 993 994 995 pages[locked_pages++] = page; 996 pvec.pages[i] = NULL; 997 998 len += PAGE_SIZE; 999 } 1000 1001 /* did we get anything? */ 1002 if (!locked_pages) 1003 goto release_pvec_pages; 1004 if (i) { 1005 unsigned j, n = 0; 1006 /* shift unused page to beginning of pvec */ 1007 for (j = 0; j < pvec_pages; j++) { 1008 if (!pvec.pages[j]) 1009 continue; 1010 if (n < j) 1011 pvec.pages[n] = pvec.pages[j]; 1012 n++; 1013 } 1014 pvec.nr = n; 1015 1016 if (pvec_pages && i == pvec_pages && 1017 locked_pages < max_pages) { 1018 dout("reached end pvec, trying for more\n"); 1019 pagevec_release(&pvec); 1020 goto get_more_pages; 1021 } 1022 } 1023 1024 new_request: 1025 offset = page_offset(pages[0]); 1026 len = wsize; 1027 1028 req = ceph_osdc_new_request(&fsc->client->osdc, 1029 &ci->i_layout, vino, 1030 offset, &len, 0, num_ops, 1031 CEPH_OSD_OP_WRITE, CEPH_OSD_FLAG_WRITE, 1032 snapc, ceph_wbc.truncate_seq, 1033 ceph_wbc.truncate_size, false); 1034 if (IS_ERR(req)) { 1035 req = ceph_osdc_new_request(&fsc->client->osdc, 1036 &ci->i_layout, vino, 1037 offset, &len, 0, 1038 min(num_ops, 1039 CEPH_OSD_SLAB_OPS), 1040 CEPH_OSD_OP_WRITE, 1041 CEPH_OSD_FLAG_WRITE, 1042 snapc, ceph_wbc.truncate_seq, 1043 ceph_wbc.truncate_size, true); 1044 BUG_ON(IS_ERR(req)); 1045 } 1046 BUG_ON(len < page_offset(pages[locked_pages - 1]) + 1047 PAGE_SIZE - offset); 1048 1049 req->r_callback = writepages_finish; 1050 req->r_inode = inode; 1051 1052 /* Format the osd request message and submit the write */ 1053 len = 0; 1054 data_pages = pages; 1055 op_idx = 0; 1056 for (i = 0; i < locked_pages; i++) { 1057 u64 cur_offset = page_offset(pages[i]); 1058 if (offset + len != cur_offset) { 1059 if (op_idx + 1 == req->r_num_ops) 1060 break; 1061 osd_req_op_extent_dup_last(req, op_idx, 1062 cur_offset - offset); 1063 dout("writepages got pages at %llu~%llu\n", 1064 offset, len); 1065 osd_req_op_extent_osd_data_pages(req, op_idx, 1066 data_pages, len, 0, 1067 !!pool, false); 1068 osd_req_op_extent_update(req, op_idx, len); 1069 1070 len = 0; 1071 offset = cur_offset; 1072 data_pages = pages + i; 1073 op_idx++; 1074 } 1075 1076 set_page_writeback(pages[i]); 1077 len += PAGE_SIZE; 1078 } 1079 1080 if (ceph_wbc.size_stable) { 1081 len = min(len, ceph_wbc.i_size - offset); 1082 } else if (i == locked_pages) { 1083 /* writepages_finish() clears writeback pages 1084 * according to the data length, so make sure 1085 * data length covers all locked pages */ 1086 u64 min_len = len + 1 - PAGE_SIZE; 1087 len = get_writepages_data_length(inode, pages[i - 1], 1088 offset); 1089 len = max(len, min_len); 1090 } 1091 dout("writepages got pages at %llu~%llu\n", offset, len); 1092 1093 osd_req_op_extent_osd_data_pages(req, op_idx, data_pages, len, 1094 0, !!pool, false); 1095 osd_req_op_extent_update(req, op_idx, len); 1096 1097 BUG_ON(op_idx + 1 != req->r_num_ops); 1098 1099 pool = NULL; 1100 if (i < locked_pages) { 1101 BUG_ON(num_ops <= req->r_num_ops); 1102 num_ops -= req->r_num_ops; 1103 locked_pages -= i; 1104 1105 /* allocate new pages array for next request */ 1106 data_pages = pages; 1107 pages = kmalloc(locked_pages * sizeof (*pages), 1108 GFP_NOFS); 1109 if (!pages) { 1110 pool = fsc->wb_pagevec_pool; 1111 pages = mempool_alloc(pool, GFP_NOFS); 1112 BUG_ON(!pages); 1113 } 1114 memcpy(pages, data_pages + i, 1115 locked_pages * sizeof(*pages)); 1116 memset(data_pages + i, 0, 1117 locked_pages * sizeof(*pages)); 1118 } else { 1119 BUG_ON(num_ops != req->r_num_ops); 1120 index = pages[i - 1]->index + 1; 1121 /* request message now owns the pages array */ 1122 pages = NULL; 1123 } 1124 1125 req->r_mtime = inode->i_mtime; 1126 rc = ceph_osdc_start_request(&fsc->client->osdc, req, true); 1127 BUG_ON(rc); 1128 req = NULL; 1129 1130 wbc->nr_to_write -= i; 1131 if (pages) 1132 goto new_request; 1133 1134 if (wbc->nr_to_write <= 0) 1135 done = 1; 1136 1137 release_pvec_pages: 1138 dout("pagevec_release on %d pages (%p)\n", (int)pvec.nr, 1139 pvec.nr ? pvec.pages[0] : NULL); 1140 pagevec_release(&pvec); 1141 1142 if (locked_pages && !done) 1143 goto retry; 1144 } 1145 1146 if (should_loop && !done) { 1147 /* more to do; loop back to beginning of file */ 1148 dout("writepages looping back to beginning of file\n"); 1149 should_loop = 0; 1150 index = 0; 1151 goto retry; 1152 } 1153 1154 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0)) 1155 mapping->writeback_index = index; 1156 1157 out: 1158 ceph_osdc_put_request(req); 1159 ceph_put_snap_context(snapc); 1160 dout("writepages done, rc = %d\n", rc); 1161 return rc; 1162 } 1163 1164 1165 1166 /* 1167 * See if a given @snapc is either writeable, or already written. 1168 */ 1169 static int context_is_writeable_or_written(struct inode *inode, 1170 struct ceph_snap_context *snapc) 1171 { 1172 struct ceph_snap_context *oldest = get_oldest_context(inode, NULL, NULL); 1173 int ret = !oldest || snapc->seq <= oldest->seq; 1174 1175 ceph_put_snap_context(oldest); 1176 return ret; 1177 } 1178 1179 /* 1180 * We are only allowed to write into/dirty the page if the page is 1181 * clean, or already dirty within the same snap context. 1182 * 1183 * called with page locked. 1184 * return success with page locked, 1185 * or any failure (incl -EAGAIN) with page unlocked. 1186 */ 1187 static int ceph_update_writeable_page(struct file *file, 1188 loff_t pos, unsigned len, 1189 struct page *page) 1190 { 1191 struct inode *inode = file_inode(file); 1192 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 1193 struct ceph_inode_info *ci = ceph_inode(inode); 1194 loff_t page_off = pos & PAGE_MASK; 1195 int pos_in_page = pos & ~PAGE_MASK; 1196 int end_in_page = pos_in_page + len; 1197 loff_t i_size; 1198 int r; 1199 struct ceph_snap_context *snapc, *oldest; 1200 1201 if (READ_ONCE(fsc->mount_state) == CEPH_MOUNT_SHUTDOWN) { 1202 dout(" page %p forced umount\n", page); 1203 unlock_page(page); 1204 return -EIO; 1205 } 1206 1207 retry_locked: 1208 /* writepages currently holds page lock, but if we change that later, */ 1209 wait_on_page_writeback(page); 1210 1211 snapc = page_snap_context(page); 1212 if (snapc && snapc != ci->i_head_snapc) { 1213 /* 1214 * this page is already dirty in another (older) snap 1215 * context! is it writeable now? 1216 */ 1217 oldest = get_oldest_context(inode, NULL, NULL); 1218 if (snapc->seq > oldest->seq) { 1219 ceph_put_snap_context(oldest); 1220 dout(" page %p snapc %p not current or oldest\n", 1221 page, snapc); 1222 /* 1223 * queue for writeback, and wait for snapc to 1224 * be writeable or written 1225 */ 1226 snapc = ceph_get_snap_context(snapc); 1227 unlock_page(page); 1228 ceph_queue_writeback(inode); 1229 r = wait_event_killable(ci->i_cap_wq, 1230 context_is_writeable_or_written(inode, snapc)); 1231 ceph_put_snap_context(snapc); 1232 if (r == -ERESTARTSYS) 1233 return r; 1234 return -EAGAIN; 1235 } 1236 ceph_put_snap_context(oldest); 1237 1238 /* yay, writeable, do it now (without dropping page lock) */ 1239 dout(" page %p snapc %p not current, but oldest\n", 1240 page, snapc); 1241 if (!clear_page_dirty_for_io(page)) 1242 goto retry_locked; 1243 r = writepage_nounlock(page, NULL); 1244 if (r < 0) 1245 goto fail_unlock; 1246 goto retry_locked; 1247 } 1248 1249 if (PageUptodate(page)) { 1250 dout(" page %p already uptodate\n", page); 1251 return 0; 1252 } 1253 1254 /* full page? */ 1255 if (pos_in_page == 0 && len == PAGE_SIZE) 1256 return 0; 1257 1258 /* past end of file? */ 1259 i_size = i_size_read(inode); 1260 1261 if (page_off >= i_size || 1262 (pos_in_page == 0 && (pos+len) >= i_size && 1263 end_in_page - pos_in_page != PAGE_SIZE)) { 1264 dout(" zeroing %p 0 - %d and %d - %d\n", 1265 page, pos_in_page, end_in_page, (int)PAGE_SIZE); 1266 zero_user_segments(page, 1267 0, pos_in_page, 1268 end_in_page, PAGE_SIZE); 1269 return 0; 1270 } 1271 1272 /* we need to read it. */ 1273 r = ceph_do_readpage(file, page); 1274 if (r < 0) { 1275 if (r == -EINPROGRESS) 1276 return -EAGAIN; 1277 goto fail_unlock; 1278 } 1279 goto retry_locked; 1280 fail_unlock: 1281 unlock_page(page); 1282 return r; 1283 } 1284 1285 /* 1286 * We are only allowed to write into/dirty the page if the page is 1287 * clean, or already dirty within the same snap context. 1288 */ 1289 static int ceph_write_begin(struct file *file, struct address_space *mapping, 1290 loff_t pos, unsigned len, unsigned flags, 1291 struct page **pagep, void **fsdata) 1292 { 1293 struct inode *inode = file_inode(file); 1294 struct page *page; 1295 pgoff_t index = pos >> PAGE_SHIFT; 1296 int r; 1297 1298 do { 1299 /* get a page */ 1300 page = grab_cache_page_write_begin(mapping, index, 0); 1301 if (!page) 1302 return -ENOMEM; 1303 1304 dout("write_begin file %p inode %p page %p %d~%d\n", file, 1305 inode, page, (int)pos, (int)len); 1306 1307 r = ceph_update_writeable_page(file, pos, len, page); 1308 if (r < 0) 1309 put_page(page); 1310 else 1311 *pagep = page; 1312 } while (r == -EAGAIN); 1313 1314 return r; 1315 } 1316 1317 /* 1318 * we don't do anything in here that simple_write_end doesn't do 1319 * except adjust dirty page accounting 1320 */ 1321 static int ceph_write_end(struct file *file, struct address_space *mapping, 1322 loff_t pos, unsigned len, unsigned copied, 1323 struct page *page, void *fsdata) 1324 { 1325 struct inode *inode = file_inode(file); 1326 bool check_cap = false; 1327 1328 dout("write_end file %p inode %p page %p %d~%d (%d)\n", file, 1329 inode, page, (int)pos, (int)copied, (int)len); 1330 1331 /* zero the stale part of the page if we did a short copy */ 1332 if (!PageUptodate(page)) { 1333 if (copied < len) { 1334 copied = 0; 1335 goto out; 1336 } 1337 SetPageUptodate(page); 1338 } 1339 1340 /* did file size increase? */ 1341 if (pos+copied > i_size_read(inode)) 1342 check_cap = ceph_inode_set_size(inode, pos+copied); 1343 1344 set_page_dirty(page); 1345 1346 out: 1347 unlock_page(page); 1348 put_page(page); 1349 1350 if (check_cap) 1351 ceph_check_caps(ceph_inode(inode), CHECK_CAPS_AUTHONLY, NULL); 1352 1353 return copied; 1354 } 1355 1356 /* 1357 * we set .direct_IO to indicate direct io is supported, but since we 1358 * intercept O_DIRECT reads and writes early, this function should 1359 * never get called. 1360 */ 1361 static ssize_t ceph_direct_io(struct kiocb *iocb, struct iov_iter *iter) 1362 { 1363 WARN_ON(1); 1364 return -EINVAL; 1365 } 1366 1367 const struct address_space_operations ceph_aops = { 1368 .readpage = ceph_readpage, 1369 .readpages = ceph_readpages, 1370 .writepage = ceph_writepage, 1371 .writepages = ceph_writepages_start, 1372 .write_begin = ceph_write_begin, 1373 .write_end = ceph_write_end, 1374 .set_page_dirty = ceph_set_page_dirty, 1375 .invalidatepage = ceph_invalidatepage, 1376 .releasepage = ceph_releasepage, 1377 .direct_IO = ceph_direct_io, 1378 }; 1379 1380 static void ceph_block_sigs(sigset_t *oldset) 1381 { 1382 sigset_t mask; 1383 siginitsetinv(&mask, sigmask(SIGKILL)); 1384 sigprocmask(SIG_BLOCK, &mask, oldset); 1385 } 1386 1387 static void ceph_restore_sigs(sigset_t *oldset) 1388 { 1389 sigprocmask(SIG_SETMASK, oldset, NULL); 1390 } 1391 1392 /* 1393 * vm ops 1394 */ 1395 static int ceph_filemap_fault(struct vm_fault *vmf) 1396 { 1397 struct vm_area_struct *vma = vmf->vma; 1398 struct inode *inode = file_inode(vma->vm_file); 1399 struct ceph_inode_info *ci = ceph_inode(inode); 1400 struct ceph_file_info *fi = vma->vm_file->private_data; 1401 struct page *pinned_page = NULL; 1402 loff_t off = vmf->pgoff << PAGE_SHIFT; 1403 int want, got, ret; 1404 sigset_t oldset; 1405 1406 ceph_block_sigs(&oldset); 1407 1408 dout("filemap_fault %p %llx.%llx %llu~%zd trying to get caps\n", 1409 inode, ceph_vinop(inode), off, (size_t)PAGE_SIZE); 1410 if (fi->fmode & CEPH_FILE_MODE_LAZY) 1411 want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO; 1412 else 1413 want = CEPH_CAP_FILE_CACHE; 1414 1415 got = 0; 1416 ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, -1, &got, &pinned_page); 1417 if (ret < 0) 1418 goto out_restore; 1419 1420 dout("filemap_fault %p %llu~%zd got cap refs on %s\n", 1421 inode, off, (size_t)PAGE_SIZE, ceph_cap_string(got)); 1422 1423 if ((got & (CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO)) || 1424 ci->i_inline_version == CEPH_INLINE_NONE) { 1425 current->journal_info = vma->vm_file; 1426 ret = filemap_fault(vmf); 1427 current->journal_info = NULL; 1428 } else 1429 ret = -EAGAIN; 1430 1431 dout("filemap_fault %p %llu~%zd dropping cap refs on %s ret %d\n", 1432 inode, off, (size_t)PAGE_SIZE, ceph_cap_string(got), ret); 1433 if (pinned_page) 1434 put_page(pinned_page); 1435 ceph_put_cap_refs(ci, got); 1436 1437 if (ret != -EAGAIN) 1438 goto out_restore; 1439 1440 /* read inline data */ 1441 if (off >= PAGE_SIZE) { 1442 /* does not support inline data > PAGE_SIZE */ 1443 ret = VM_FAULT_SIGBUS; 1444 } else { 1445 int ret1; 1446 struct address_space *mapping = inode->i_mapping; 1447 struct page *page = find_or_create_page(mapping, 0, 1448 mapping_gfp_constraint(mapping, 1449 ~__GFP_FS)); 1450 if (!page) { 1451 ret = VM_FAULT_OOM; 1452 goto out_inline; 1453 } 1454 ret1 = __ceph_do_getattr(inode, page, 1455 CEPH_STAT_CAP_INLINE_DATA, true); 1456 if (ret1 < 0 || off >= i_size_read(inode)) { 1457 unlock_page(page); 1458 put_page(page); 1459 if (ret1 < 0) 1460 ret = ret1; 1461 else 1462 ret = VM_FAULT_SIGBUS; 1463 goto out_inline; 1464 } 1465 if (ret1 < PAGE_SIZE) 1466 zero_user_segment(page, ret1, PAGE_SIZE); 1467 else 1468 flush_dcache_page(page); 1469 SetPageUptodate(page); 1470 vmf->page = page; 1471 ret = VM_FAULT_MAJOR | VM_FAULT_LOCKED; 1472 out_inline: 1473 dout("filemap_fault %p %llu~%zd read inline data ret %d\n", 1474 inode, off, (size_t)PAGE_SIZE, ret); 1475 } 1476 out_restore: 1477 ceph_restore_sigs(&oldset); 1478 if (ret < 0) 1479 ret = (ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS; 1480 1481 return ret; 1482 } 1483 1484 /* 1485 * Reuse write_begin here for simplicity. 1486 */ 1487 static int ceph_page_mkwrite(struct vm_fault *vmf) 1488 { 1489 struct vm_area_struct *vma = vmf->vma; 1490 struct inode *inode = file_inode(vma->vm_file); 1491 struct ceph_inode_info *ci = ceph_inode(inode); 1492 struct ceph_file_info *fi = vma->vm_file->private_data; 1493 struct ceph_cap_flush *prealloc_cf; 1494 struct page *page = vmf->page; 1495 loff_t off = page_offset(page); 1496 loff_t size = i_size_read(inode); 1497 size_t len; 1498 int want, got, ret; 1499 sigset_t oldset; 1500 1501 prealloc_cf = ceph_alloc_cap_flush(); 1502 if (!prealloc_cf) 1503 return VM_FAULT_OOM; 1504 1505 ceph_block_sigs(&oldset); 1506 1507 if (ci->i_inline_version != CEPH_INLINE_NONE) { 1508 struct page *locked_page = NULL; 1509 if (off == 0) { 1510 lock_page(page); 1511 locked_page = page; 1512 } 1513 ret = ceph_uninline_data(vma->vm_file, locked_page); 1514 if (locked_page) 1515 unlock_page(locked_page); 1516 if (ret < 0) 1517 goto out_free; 1518 } 1519 1520 if (off + PAGE_SIZE <= size) 1521 len = PAGE_SIZE; 1522 else 1523 len = size & ~PAGE_MASK; 1524 1525 dout("page_mkwrite %p %llx.%llx %llu~%zd getting caps i_size %llu\n", 1526 inode, ceph_vinop(inode), off, len, size); 1527 if (fi->fmode & CEPH_FILE_MODE_LAZY) 1528 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO; 1529 else 1530 want = CEPH_CAP_FILE_BUFFER; 1531 1532 got = 0; 1533 ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, off + len, 1534 &got, NULL); 1535 if (ret < 0) 1536 goto out_free; 1537 1538 dout("page_mkwrite %p %llu~%zd got cap refs on %s\n", 1539 inode, off, len, ceph_cap_string(got)); 1540 1541 /* Update time before taking page lock */ 1542 file_update_time(vma->vm_file); 1543 1544 do { 1545 lock_page(page); 1546 1547 if ((off > size) || (page->mapping != inode->i_mapping)) { 1548 unlock_page(page); 1549 ret = VM_FAULT_NOPAGE; 1550 break; 1551 } 1552 1553 ret = ceph_update_writeable_page(vma->vm_file, off, len, page); 1554 if (ret >= 0) { 1555 /* success. we'll keep the page locked. */ 1556 set_page_dirty(page); 1557 ret = VM_FAULT_LOCKED; 1558 } 1559 } while (ret == -EAGAIN); 1560 1561 if (ret == VM_FAULT_LOCKED || 1562 ci->i_inline_version != CEPH_INLINE_NONE) { 1563 int dirty; 1564 spin_lock(&ci->i_ceph_lock); 1565 ci->i_inline_version = CEPH_INLINE_NONE; 1566 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR, 1567 &prealloc_cf); 1568 spin_unlock(&ci->i_ceph_lock); 1569 if (dirty) 1570 __mark_inode_dirty(inode, dirty); 1571 } 1572 1573 dout("page_mkwrite %p %llu~%zd dropping cap refs on %s ret %d\n", 1574 inode, off, len, ceph_cap_string(got), ret); 1575 ceph_put_cap_refs(ci, got); 1576 out_free: 1577 ceph_restore_sigs(&oldset); 1578 ceph_free_cap_flush(prealloc_cf); 1579 if (ret < 0) 1580 ret = (ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS; 1581 return ret; 1582 } 1583 1584 void ceph_fill_inline_data(struct inode *inode, struct page *locked_page, 1585 char *data, size_t len) 1586 { 1587 struct address_space *mapping = inode->i_mapping; 1588 struct page *page; 1589 1590 if (locked_page) { 1591 page = locked_page; 1592 } else { 1593 if (i_size_read(inode) == 0) 1594 return; 1595 page = find_or_create_page(mapping, 0, 1596 mapping_gfp_constraint(mapping, 1597 ~__GFP_FS)); 1598 if (!page) 1599 return; 1600 if (PageUptodate(page)) { 1601 unlock_page(page); 1602 put_page(page); 1603 return; 1604 } 1605 } 1606 1607 dout("fill_inline_data %p %llx.%llx len %zu locked_page %p\n", 1608 inode, ceph_vinop(inode), len, locked_page); 1609 1610 if (len > 0) { 1611 void *kaddr = kmap_atomic(page); 1612 memcpy(kaddr, data, len); 1613 kunmap_atomic(kaddr); 1614 } 1615 1616 if (page != locked_page) { 1617 if (len < PAGE_SIZE) 1618 zero_user_segment(page, len, PAGE_SIZE); 1619 else 1620 flush_dcache_page(page); 1621 1622 SetPageUptodate(page); 1623 unlock_page(page); 1624 put_page(page); 1625 } 1626 } 1627 1628 int ceph_uninline_data(struct file *filp, struct page *locked_page) 1629 { 1630 struct inode *inode = file_inode(filp); 1631 struct ceph_inode_info *ci = ceph_inode(inode); 1632 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 1633 struct ceph_osd_request *req; 1634 struct page *page = NULL; 1635 u64 len, inline_version; 1636 int err = 0; 1637 bool from_pagecache = false; 1638 1639 spin_lock(&ci->i_ceph_lock); 1640 inline_version = ci->i_inline_version; 1641 spin_unlock(&ci->i_ceph_lock); 1642 1643 dout("uninline_data %p %llx.%llx inline_version %llu\n", 1644 inode, ceph_vinop(inode), inline_version); 1645 1646 if (inline_version == 1 || /* initial version, no data */ 1647 inline_version == CEPH_INLINE_NONE) 1648 goto out; 1649 1650 if (locked_page) { 1651 page = locked_page; 1652 WARN_ON(!PageUptodate(page)); 1653 } else if (ceph_caps_issued(ci) & 1654 (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) { 1655 page = find_get_page(inode->i_mapping, 0); 1656 if (page) { 1657 if (PageUptodate(page)) { 1658 from_pagecache = true; 1659 lock_page(page); 1660 } else { 1661 put_page(page); 1662 page = NULL; 1663 } 1664 } 1665 } 1666 1667 if (page) { 1668 len = i_size_read(inode); 1669 if (len > PAGE_SIZE) 1670 len = PAGE_SIZE; 1671 } else { 1672 page = __page_cache_alloc(GFP_NOFS); 1673 if (!page) { 1674 err = -ENOMEM; 1675 goto out; 1676 } 1677 err = __ceph_do_getattr(inode, page, 1678 CEPH_STAT_CAP_INLINE_DATA, true); 1679 if (err < 0) { 1680 /* no inline data */ 1681 if (err == -ENODATA) 1682 err = 0; 1683 goto out; 1684 } 1685 len = err; 1686 } 1687 1688 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout, 1689 ceph_vino(inode), 0, &len, 0, 1, 1690 CEPH_OSD_OP_CREATE, CEPH_OSD_FLAG_WRITE, 1691 NULL, 0, 0, false); 1692 if (IS_ERR(req)) { 1693 err = PTR_ERR(req); 1694 goto out; 1695 } 1696 1697 req->r_mtime = inode->i_mtime; 1698 err = ceph_osdc_start_request(&fsc->client->osdc, req, false); 1699 if (!err) 1700 err = ceph_osdc_wait_request(&fsc->client->osdc, req); 1701 ceph_osdc_put_request(req); 1702 if (err < 0) 1703 goto out; 1704 1705 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout, 1706 ceph_vino(inode), 0, &len, 1, 3, 1707 CEPH_OSD_OP_WRITE, CEPH_OSD_FLAG_WRITE, 1708 NULL, ci->i_truncate_seq, 1709 ci->i_truncate_size, false); 1710 if (IS_ERR(req)) { 1711 err = PTR_ERR(req); 1712 goto out; 1713 } 1714 1715 osd_req_op_extent_osd_data_pages(req, 1, &page, len, 0, false, false); 1716 1717 { 1718 __le64 xattr_buf = cpu_to_le64(inline_version); 1719 err = osd_req_op_xattr_init(req, 0, CEPH_OSD_OP_CMPXATTR, 1720 "inline_version", &xattr_buf, 1721 sizeof(xattr_buf), 1722 CEPH_OSD_CMPXATTR_OP_GT, 1723 CEPH_OSD_CMPXATTR_MODE_U64); 1724 if (err) 1725 goto out_put; 1726 } 1727 1728 { 1729 char xattr_buf[32]; 1730 int xattr_len = snprintf(xattr_buf, sizeof(xattr_buf), 1731 "%llu", inline_version); 1732 err = osd_req_op_xattr_init(req, 2, CEPH_OSD_OP_SETXATTR, 1733 "inline_version", 1734 xattr_buf, xattr_len, 0, 0); 1735 if (err) 1736 goto out_put; 1737 } 1738 1739 req->r_mtime = inode->i_mtime; 1740 err = ceph_osdc_start_request(&fsc->client->osdc, req, false); 1741 if (!err) 1742 err = ceph_osdc_wait_request(&fsc->client->osdc, req); 1743 out_put: 1744 ceph_osdc_put_request(req); 1745 if (err == -ECANCELED) 1746 err = 0; 1747 out: 1748 if (page && page != locked_page) { 1749 if (from_pagecache) { 1750 unlock_page(page); 1751 put_page(page); 1752 } else 1753 __free_pages(page, 0); 1754 } 1755 1756 dout("uninline_data %p %llx.%llx inline_version %llu = %d\n", 1757 inode, ceph_vinop(inode), inline_version, err); 1758 return err; 1759 } 1760 1761 static const struct vm_operations_struct ceph_vmops = { 1762 .fault = ceph_filemap_fault, 1763 .page_mkwrite = ceph_page_mkwrite, 1764 }; 1765 1766 int ceph_mmap(struct file *file, struct vm_area_struct *vma) 1767 { 1768 struct address_space *mapping = file->f_mapping; 1769 1770 if (!mapping->a_ops->readpage) 1771 return -ENOEXEC; 1772 file_accessed(file); 1773 vma->vm_ops = &ceph_vmops; 1774 return 0; 1775 } 1776 1777 enum { 1778 POOL_READ = 1, 1779 POOL_WRITE = 2, 1780 }; 1781 1782 static int __ceph_pool_perm_get(struct ceph_inode_info *ci, 1783 s64 pool, struct ceph_string *pool_ns) 1784 { 1785 struct ceph_fs_client *fsc = ceph_inode_to_client(&ci->vfs_inode); 1786 struct ceph_mds_client *mdsc = fsc->mdsc; 1787 struct ceph_osd_request *rd_req = NULL, *wr_req = NULL; 1788 struct rb_node **p, *parent; 1789 struct ceph_pool_perm *perm; 1790 struct page **pages; 1791 size_t pool_ns_len; 1792 int err = 0, err2 = 0, have = 0; 1793 1794 down_read(&mdsc->pool_perm_rwsem); 1795 p = &mdsc->pool_perm_tree.rb_node; 1796 while (*p) { 1797 perm = rb_entry(*p, struct ceph_pool_perm, node); 1798 if (pool < perm->pool) 1799 p = &(*p)->rb_left; 1800 else if (pool > perm->pool) 1801 p = &(*p)->rb_right; 1802 else { 1803 int ret = ceph_compare_string(pool_ns, 1804 perm->pool_ns, 1805 perm->pool_ns_len); 1806 if (ret < 0) 1807 p = &(*p)->rb_left; 1808 else if (ret > 0) 1809 p = &(*p)->rb_right; 1810 else { 1811 have = perm->perm; 1812 break; 1813 } 1814 } 1815 } 1816 up_read(&mdsc->pool_perm_rwsem); 1817 if (*p) 1818 goto out; 1819 1820 if (pool_ns) 1821 dout("__ceph_pool_perm_get pool %lld ns %.*s no perm cached\n", 1822 pool, (int)pool_ns->len, pool_ns->str); 1823 else 1824 dout("__ceph_pool_perm_get pool %lld no perm cached\n", pool); 1825 1826 down_write(&mdsc->pool_perm_rwsem); 1827 p = &mdsc->pool_perm_tree.rb_node; 1828 parent = NULL; 1829 while (*p) { 1830 parent = *p; 1831 perm = rb_entry(parent, struct ceph_pool_perm, node); 1832 if (pool < perm->pool) 1833 p = &(*p)->rb_left; 1834 else if (pool > perm->pool) 1835 p = &(*p)->rb_right; 1836 else { 1837 int ret = ceph_compare_string(pool_ns, 1838 perm->pool_ns, 1839 perm->pool_ns_len); 1840 if (ret < 0) 1841 p = &(*p)->rb_left; 1842 else if (ret > 0) 1843 p = &(*p)->rb_right; 1844 else { 1845 have = perm->perm; 1846 break; 1847 } 1848 } 1849 } 1850 if (*p) { 1851 up_write(&mdsc->pool_perm_rwsem); 1852 goto out; 1853 } 1854 1855 rd_req = ceph_osdc_alloc_request(&fsc->client->osdc, NULL, 1856 1, false, GFP_NOFS); 1857 if (!rd_req) { 1858 err = -ENOMEM; 1859 goto out_unlock; 1860 } 1861 1862 rd_req->r_flags = CEPH_OSD_FLAG_READ; 1863 osd_req_op_init(rd_req, 0, CEPH_OSD_OP_STAT, 0); 1864 rd_req->r_base_oloc.pool = pool; 1865 if (pool_ns) 1866 rd_req->r_base_oloc.pool_ns = ceph_get_string(pool_ns); 1867 ceph_oid_printf(&rd_req->r_base_oid, "%llx.00000000", ci->i_vino.ino); 1868 1869 err = ceph_osdc_alloc_messages(rd_req, GFP_NOFS); 1870 if (err) 1871 goto out_unlock; 1872 1873 wr_req = ceph_osdc_alloc_request(&fsc->client->osdc, NULL, 1874 1, false, GFP_NOFS); 1875 if (!wr_req) { 1876 err = -ENOMEM; 1877 goto out_unlock; 1878 } 1879 1880 wr_req->r_flags = CEPH_OSD_FLAG_WRITE; 1881 osd_req_op_init(wr_req, 0, CEPH_OSD_OP_CREATE, CEPH_OSD_OP_FLAG_EXCL); 1882 ceph_oloc_copy(&wr_req->r_base_oloc, &rd_req->r_base_oloc); 1883 ceph_oid_copy(&wr_req->r_base_oid, &rd_req->r_base_oid); 1884 1885 err = ceph_osdc_alloc_messages(wr_req, GFP_NOFS); 1886 if (err) 1887 goto out_unlock; 1888 1889 /* one page should be large enough for STAT data */ 1890 pages = ceph_alloc_page_vector(1, GFP_KERNEL); 1891 if (IS_ERR(pages)) { 1892 err = PTR_ERR(pages); 1893 goto out_unlock; 1894 } 1895 1896 osd_req_op_raw_data_in_pages(rd_req, 0, pages, PAGE_SIZE, 1897 0, false, true); 1898 err = ceph_osdc_start_request(&fsc->client->osdc, rd_req, false); 1899 1900 wr_req->r_mtime = ci->vfs_inode.i_mtime; 1901 wr_req->r_abort_on_full = true; 1902 err2 = ceph_osdc_start_request(&fsc->client->osdc, wr_req, false); 1903 1904 if (!err) 1905 err = ceph_osdc_wait_request(&fsc->client->osdc, rd_req); 1906 if (!err2) 1907 err2 = ceph_osdc_wait_request(&fsc->client->osdc, wr_req); 1908 1909 if (err >= 0 || err == -ENOENT) 1910 have |= POOL_READ; 1911 else if (err != -EPERM) 1912 goto out_unlock; 1913 1914 if (err2 == 0 || err2 == -EEXIST) 1915 have |= POOL_WRITE; 1916 else if (err2 != -EPERM) { 1917 err = err2; 1918 goto out_unlock; 1919 } 1920 1921 pool_ns_len = pool_ns ? pool_ns->len : 0; 1922 perm = kmalloc(sizeof(*perm) + pool_ns_len + 1, GFP_NOFS); 1923 if (!perm) { 1924 err = -ENOMEM; 1925 goto out_unlock; 1926 } 1927 1928 perm->pool = pool; 1929 perm->perm = have; 1930 perm->pool_ns_len = pool_ns_len; 1931 if (pool_ns_len > 0) 1932 memcpy(perm->pool_ns, pool_ns->str, pool_ns_len); 1933 perm->pool_ns[pool_ns_len] = 0; 1934 1935 rb_link_node(&perm->node, parent, p); 1936 rb_insert_color(&perm->node, &mdsc->pool_perm_tree); 1937 err = 0; 1938 out_unlock: 1939 up_write(&mdsc->pool_perm_rwsem); 1940 1941 ceph_osdc_put_request(rd_req); 1942 ceph_osdc_put_request(wr_req); 1943 out: 1944 if (!err) 1945 err = have; 1946 if (pool_ns) 1947 dout("__ceph_pool_perm_get pool %lld ns %.*s result = %d\n", 1948 pool, (int)pool_ns->len, pool_ns->str, err); 1949 else 1950 dout("__ceph_pool_perm_get pool %lld result = %d\n", pool, err); 1951 return err; 1952 } 1953 1954 int ceph_pool_perm_check(struct ceph_inode_info *ci, int need) 1955 { 1956 s64 pool; 1957 struct ceph_string *pool_ns; 1958 int ret, flags; 1959 1960 if (ci->i_vino.snap != CEPH_NOSNAP) { 1961 /* 1962 * Pool permission check needs to write to the first object. 1963 * But for snapshot, head of the first object may have alread 1964 * been deleted. Skip check to avoid creating orphan object. 1965 */ 1966 return 0; 1967 } 1968 1969 if (ceph_test_mount_opt(ceph_inode_to_client(&ci->vfs_inode), 1970 NOPOOLPERM)) 1971 return 0; 1972 1973 spin_lock(&ci->i_ceph_lock); 1974 flags = ci->i_ceph_flags; 1975 pool = ci->i_layout.pool_id; 1976 spin_unlock(&ci->i_ceph_lock); 1977 check: 1978 if (flags & CEPH_I_POOL_PERM) { 1979 if ((need & CEPH_CAP_FILE_RD) && !(flags & CEPH_I_POOL_RD)) { 1980 dout("ceph_pool_perm_check pool %lld no read perm\n", 1981 pool); 1982 return -EPERM; 1983 } 1984 if ((need & CEPH_CAP_FILE_WR) && !(flags & CEPH_I_POOL_WR)) { 1985 dout("ceph_pool_perm_check pool %lld no write perm\n", 1986 pool); 1987 return -EPERM; 1988 } 1989 return 0; 1990 } 1991 1992 pool_ns = ceph_try_get_string(ci->i_layout.pool_ns); 1993 ret = __ceph_pool_perm_get(ci, pool, pool_ns); 1994 ceph_put_string(pool_ns); 1995 if (ret < 0) 1996 return ret; 1997 1998 flags = CEPH_I_POOL_PERM; 1999 if (ret & POOL_READ) 2000 flags |= CEPH_I_POOL_RD; 2001 if (ret & POOL_WRITE) 2002 flags |= CEPH_I_POOL_WR; 2003 2004 spin_lock(&ci->i_ceph_lock); 2005 if (pool == ci->i_layout.pool_id && 2006 pool_ns == rcu_dereference_raw(ci->i_layout.pool_ns)) { 2007 ci->i_ceph_flags |= flags; 2008 } else { 2009 pool = ci->i_layout.pool_id; 2010 flags = ci->i_ceph_flags; 2011 } 2012 spin_unlock(&ci->i_ceph_lock); 2013 goto check; 2014 } 2015 2016 void ceph_pool_perm_destroy(struct ceph_mds_client *mdsc) 2017 { 2018 struct ceph_pool_perm *perm; 2019 struct rb_node *n; 2020 2021 while (!RB_EMPTY_ROOT(&mdsc->pool_perm_tree)) { 2022 n = rb_first(&mdsc->pool_perm_tree); 2023 perm = rb_entry(n, struct ceph_pool_perm, node); 2024 rb_erase(n, &mdsc->pool_perm_tree); 2025 kfree(perm); 2026 } 2027 } 2028