1 /* 2 * linux/fs/nfs/blocklayout/blocklayout.c 3 * 4 * Module for the NFSv4.1 pNFS block layout driver. 5 * 6 * Copyright (c) 2006 The Regents of the University of Michigan. 7 * All rights reserved. 8 * 9 * Andy Adamson <andros@citi.umich.edu> 10 * Fred Isaman <iisaman@umich.edu> 11 * 12 * permission is granted to use, copy, create derivative works and 13 * redistribute this software and such derivative works for any purpose, 14 * so long as the name of the university of michigan is not used in 15 * any advertising or publicity pertaining to the use or distribution 16 * of this software without specific, written prior authorization. if 17 * the above copyright notice or any other identification of the 18 * university of michigan is included in any copy of any portion of 19 * this software, then the disclaimer below must also be included. 20 * 21 * this software is provided as is, without representation from the 22 * university of michigan as to its fitness for any purpose, and without 23 * warranty by the university of michigan of any kind, either express 24 * or implied, including without limitation the implied warranties of 25 * merchantability and fitness for a particular purpose. the regents 26 * of the university of michigan shall not be liable for any damages, 27 * including special, indirect, incidental, or consequential damages, 28 * with respect to any claim arising out or in connection with the use 29 * of the software, even if it has been or is hereafter advised of the 30 * possibility of such damages. 31 */ 32 33 #include <linux/module.h> 34 #include <linux/init.h> 35 #include <linux/mount.h> 36 #include <linux/namei.h> 37 #include <linux/bio.h> /* struct bio */ 38 #include <linux/prefetch.h> 39 #include <linux/pagevec.h> 40 41 #include "../pnfs.h" 42 #include "../nfs4session.h" 43 #include "../internal.h" 44 #include "blocklayout.h" 45 46 #define NFSDBG_FACILITY NFSDBG_PNFS_LD 47 48 MODULE_LICENSE("GPL"); 49 MODULE_AUTHOR("Andy Adamson <andros@citi.umich.edu>"); 50 MODULE_DESCRIPTION("The NFSv4.1 pNFS Block layout driver"); 51 52 static bool is_hole(struct pnfs_block_extent *be) 53 { 54 switch (be->be_state) { 55 case PNFS_BLOCK_NONE_DATA: 56 return true; 57 case PNFS_BLOCK_INVALID_DATA: 58 return be->be_tag ? false : true; 59 default: 60 return false; 61 } 62 } 63 64 /* The data we are handed might be spread across several bios. We need 65 * to track when the last one is finished. 66 */ 67 struct parallel_io { 68 struct kref refcnt; 69 void (*pnfs_callback) (void *data); 70 void *data; 71 }; 72 73 static inline struct parallel_io *alloc_parallel(void *data) 74 { 75 struct parallel_io *rv; 76 77 rv = kmalloc(sizeof(*rv), GFP_NOFS); 78 if (rv) { 79 rv->data = data; 80 kref_init(&rv->refcnt); 81 } 82 return rv; 83 } 84 85 static inline void get_parallel(struct parallel_io *p) 86 { 87 kref_get(&p->refcnt); 88 } 89 90 static void destroy_parallel(struct kref *kref) 91 { 92 struct parallel_io *p = container_of(kref, struct parallel_io, refcnt); 93 94 dprintk("%s enter\n", __func__); 95 p->pnfs_callback(p->data); 96 kfree(p); 97 } 98 99 static inline void put_parallel(struct parallel_io *p) 100 { 101 kref_put(&p->refcnt, destroy_parallel); 102 } 103 104 static struct bio * 105 bl_submit_bio(int rw, struct bio *bio) 106 { 107 if (bio) { 108 get_parallel(bio->bi_private); 109 dprintk("%s submitting %s bio %u@%llu\n", __func__, 110 rw == READ ? "read" : "write", bio->bi_iter.bi_size, 111 (unsigned long long)bio->bi_iter.bi_sector); 112 submit_bio(rw, bio); 113 } 114 return NULL; 115 } 116 117 static struct bio * 118 bl_alloc_init_bio(int npg, struct block_device *bdev, sector_t disk_sector, 119 bio_end_io_t end_io, struct parallel_io *par) 120 { 121 struct bio *bio; 122 123 npg = min(npg, BIO_MAX_PAGES); 124 bio = bio_alloc(GFP_NOIO, npg); 125 if (!bio && (current->flags & PF_MEMALLOC)) { 126 while (!bio && (npg /= 2)) 127 bio = bio_alloc(GFP_NOIO, npg); 128 } 129 130 if (bio) { 131 bio->bi_iter.bi_sector = disk_sector; 132 bio->bi_bdev = bdev; 133 bio->bi_end_io = end_io; 134 bio->bi_private = par; 135 } 136 return bio; 137 } 138 139 static struct bio * 140 do_add_page_to_bio(struct bio *bio, int npg, int rw, sector_t isect, 141 struct page *page, struct pnfs_block_dev_map *map, 142 struct pnfs_block_extent *be, bio_end_io_t end_io, 143 struct parallel_io *par, unsigned int offset, int *len) 144 { 145 struct pnfs_block_dev *dev = 146 container_of(be->be_device, struct pnfs_block_dev, node); 147 u64 disk_addr, end; 148 149 dprintk("%s: npg %d rw %d isect %llu offset %u len %d\n", __func__, 150 npg, rw, (unsigned long long)isect, offset, *len); 151 152 /* translate to device offset */ 153 isect += be->be_v_offset; 154 isect -= be->be_f_offset; 155 156 /* translate to physical disk offset */ 157 disk_addr = (u64)isect << SECTOR_SHIFT; 158 if (disk_addr < map->start || disk_addr >= map->start + map->len) { 159 if (!dev->map(dev, disk_addr, map)) 160 return ERR_PTR(-EIO); 161 bio = bl_submit_bio(rw, bio); 162 } 163 disk_addr += map->disk_offset; 164 disk_addr -= map->start; 165 166 /* limit length to what the device mapping allows */ 167 end = disk_addr + *len; 168 if (end >= map->start + map->len) 169 *len = map->start + map->len - disk_addr; 170 171 retry: 172 if (!bio) { 173 bio = bl_alloc_init_bio(npg, map->bdev, 174 disk_addr >> SECTOR_SHIFT, end_io, par); 175 if (!bio) 176 return ERR_PTR(-ENOMEM); 177 } 178 if (bio_add_page(bio, page, *len, offset) < *len) { 179 bio = bl_submit_bio(rw, bio); 180 goto retry; 181 } 182 return bio; 183 } 184 185 static void bl_end_io_read(struct bio *bio) 186 { 187 struct parallel_io *par = bio->bi_private; 188 189 if (bio->bi_error) { 190 struct nfs_pgio_header *header = par->data; 191 192 if (!header->pnfs_error) 193 header->pnfs_error = -EIO; 194 pnfs_set_lo_fail(header->lseg); 195 } 196 197 bio_put(bio); 198 put_parallel(par); 199 } 200 201 static void bl_read_cleanup(struct work_struct *work) 202 { 203 struct rpc_task *task; 204 struct nfs_pgio_header *hdr; 205 dprintk("%s enter\n", __func__); 206 task = container_of(work, struct rpc_task, u.tk_work); 207 hdr = container_of(task, struct nfs_pgio_header, task); 208 pnfs_ld_read_done(hdr); 209 } 210 211 static void 212 bl_end_par_io_read(void *data) 213 { 214 struct nfs_pgio_header *hdr = data; 215 216 hdr->task.tk_status = hdr->pnfs_error; 217 INIT_WORK(&hdr->task.u.tk_work, bl_read_cleanup); 218 schedule_work(&hdr->task.u.tk_work); 219 } 220 221 static enum pnfs_try_status 222 bl_read_pagelist(struct nfs_pgio_header *header) 223 { 224 struct pnfs_block_layout *bl = BLK_LSEG2EXT(header->lseg); 225 struct pnfs_block_dev_map map = { .start = NFS4_MAX_UINT64 }; 226 struct bio *bio = NULL; 227 struct pnfs_block_extent be; 228 sector_t isect, extent_length = 0; 229 struct parallel_io *par; 230 loff_t f_offset = header->args.offset; 231 size_t bytes_left = header->args.count; 232 unsigned int pg_offset = header->args.pgbase, pg_len; 233 struct page **pages = header->args.pages; 234 int pg_index = header->args.pgbase >> PAGE_SHIFT; 235 const bool is_dio = (header->dreq != NULL); 236 struct blk_plug plug; 237 int i; 238 239 dprintk("%s enter nr_pages %u offset %lld count %u\n", __func__, 240 header->page_array.npages, f_offset, 241 (unsigned int)header->args.count); 242 243 par = alloc_parallel(header); 244 if (!par) 245 return PNFS_NOT_ATTEMPTED; 246 par->pnfs_callback = bl_end_par_io_read; 247 248 blk_start_plug(&plug); 249 250 isect = (sector_t) (f_offset >> SECTOR_SHIFT); 251 /* Code assumes extents are page-aligned */ 252 for (i = pg_index; i < header->page_array.npages; i++) { 253 if (extent_length <= 0) { 254 /* We've used up the previous extent */ 255 bio = bl_submit_bio(READ, bio); 256 257 /* Get the next one */ 258 if (!ext_tree_lookup(bl, isect, &be, false)) { 259 header->pnfs_error = -EIO; 260 goto out; 261 } 262 extent_length = be.be_length - (isect - be.be_f_offset); 263 } 264 265 if (is_dio) { 266 if (pg_offset + bytes_left > PAGE_SIZE) 267 pg_len = PAGE_SIZE - pg_offset; 268 else 269 pg_len = bytes_left; 270 } else { 271 BUG_ON(pg_offset != 0); 272 pg_len = PAGE_SIZE; 273 } 274 275 if (is_hole(&be)) { 276 bio = bl_submit_bio(READ, bio); 277 /* Fill hole w/ zeroes w/o accessing device */ 278 dprintk("%s Zeroing page for hole\n", __func__); 279 zero_user_segment(pages[i], pg_offset, pg_len); 280 281 /* invalidate map */ 282 map.start = NFS4_MAX_UINT64; 283 } else { 284 bio = do_add_page_to_bio(bio, 285 header->page_array.npages - i, 286 READ, 287 isect, pages[i], &map, &be, 288 bl_end_io_read, par, 289 pg_offset, &pg_len); 290 if (IS_ERR(bio)) { 291 header->pnfs_error = PTR_ERR(bio); 292 bio = NULL; 293 goto out; 294 } 295 } 296 isect += (pg_len >> SECTOR_SHIFT); 297 extent_length -= (pg_len >> SECTOR_SHIFT); 298 f_offset += pg_len; 299 bytes_left -= pg_len; 300 pg_offset = 0; 301 } 302 if ((isect << SECTOR_SHIFT) >= header->inode->i_size) { 303 header->res.eof = 1; 304 header->res.count = header->inode->i_size - header->args.offset; 305 } else { 306 header->res.count = (isect << SECTOR_SHIFT) - header->args.offset; 307 } 308 out: 309 bl_submit_bio(READ, bio); 310 blk_finish_plug(&plug); 311 put_parallel(par); 312 return PNFS_ATTEMPTED; 313 } 314 315 static void bl_end_io_write(struct bio *bio) 316 { 317 struct parallel_io *par = bio->bi_private; 318 struct nfs_pgio_header *header = par->data; 319 320 if (bio->bi_error) { 321 if (!header->pnfs_error) 322 header->pnfs_error = -EIO; 323 pnfs_set_lo_fail(header->lseg); 324 } 325 bio_put(bio); 326 put_parallel(par); 327 } 328 329 /* Function scheduled for call during bl_end_par_io_write, 330 * it marks sectors as written and extends the commitlist. 331 */ 332 static void bl_write_cleanup(struct work_struct *work) 333 { 334 struct rpc_task *task = container_of(work, struct rpc_task, u.tk_work); 335 struct nfs_pgio_header *hdr = 336 container_of(task, struct nfs_pgio_header, task); 337 338 dprintk("%s enter\n", __func__); 339 340 if (likely(!hdr->pnfs_error)) { 341 struct pnfs_block_layout *bl = BLK_LSEG2EXT(hdr->lseg); 342 u64 start = hdr->args.offset & (loff_t)PAGE_MASK; 343 u64 end = (hdr->args.offset + hdr->args.count + 344 PAGE_SIZE - 1) & (loff_t)PAGE_MASK; 345 346 ext_tree_mark_written(bl, start >> SECTOR_SHIFT, 347 (end - start) >> SECTOR_SHIFT); 348 } 349 350 pnfs_ld_write_done(hdr); 351 } 352 353 /* Called when last of bios associated with a bl_write_pagelist call finishes */ 354 static void bl_end_par_io_write(void *data) 355 { 356 struct nfs_pgio_header *hdr = data; 357 358 hdr->task.tk_status = hdr->pnfs_error; 359 hdr->verf.committed = NFS_FILE_SYNC; 360 INIT_WORK(&hdr->task.u.tk_work, bl_write_cleanup); 361 schedule_work(&hdr->task.u.tk_work); 362 } 363 364 static enum pnfs_try_status 365 bl_write_pagelist(struct nfs_pgio_header *header, int sync) 366 { 367 struct pnfs_block_layout *bl = BLK_LSEG2EXT(header->lseg); 368 struct pnfs_block_dev_map map = { .start = NFS4_MAX_UINT64 }; 369 struct bio *bio = NULL; 370 struct pnfs_block_extent be; 371 sector_t isect, extent_length = 0; 372 struct parallel_io *par = NULL; 373 loff_t offset = header->args.offset; 374 size_t count = header->args.count; 375 struct page **pages = header->args.pages; 376 int pg_index = header->args.pgbase >> PAGE_SHIFT; 377 unsigned int pg_len; 378 struct blk_plug plug; 379 int i; 380 381 dprintk("%s enter, %Zu@%lld\n", __func__, count, offset); 382 383 /* At this point, header->page_aray is a (sequential) list of nfs_pages. 384 * We want to write each, and if there is an error set pnfs_error 385 * to have it redone using nfs. 386 */ 387 par = alloc_parallel(header); 388 if (!par) 389 return PNFS_NOT_ATTEMPTED; 390 par->pnfs_callback = bl_end_par_io_write; 391 392 blk_start_plug(&plug); 393 394 /* we always write out the whole page */ 395 offset = offset & (loff_t)PAGE_MASK; 396 isect = offset >> SECTOR_SHIFT; 397 398 for (i = pg_index; i < header->page_array.npages; i++) { 399 if (extent_length <= 0) { 400 /* We've used up the previous extent */ 401 bio = bl_submit_bio(WRITE, bio); 402 /* Get the next one */ 403 if (!ext_tree_lookup(bl, isect, &be, true)) { 404 header->pnfs_error = -EINVAL; 405 goto out; 406 } 407 408 extent_length = be.be_length - (isect - be.be_f_offset); 409 } 410 411 pg_len = PAGE_SIZE; 412 bio = do_add_page_to_bio(bio, header->page_array.npages - i, 413 WRITE, isect, pages[i], &map, &be, 414 bl_end_io_write, par, 415 0, &pg_len); 416 if (IS_ERR(bio)) { 417 header->pnfs_error = PTR_ERR(bio); 418 bio = NULL; 419 goto out; 420 } 421 422 offset += pg_len; 423 count -= pg_len; 424 isect += (pg_len >> SECTOR_SHIFT); 425 extent_length -= (pg_len >> SECTOR_SHIFT); 426 } 427 428 header->res.count = header->args.count; 429 out: 430 bl_submit_bio(WRITE, bio); 431 blk_finish_plug(&plug); 432 put_parallel(par); 433 return PNFS_ATTEMPTED; 434 } 435 436 static void bl_free_layout_hdr(struct pnfs_layout_hdr *lo) 437 { 438 struct pnfs_block_layout *bl = BLK_LO2EXT(lo); 439 int err; 440 441 dprintk("%s enter\n", __func__); 442 443 err = ext_tree_remove(bl, true, 0, LLONG_MAX); 444 WARN_ON(err); 445 446 kfree(bl); 447 } 448 449 static struct pnfs_layout_hdr *__bl_alloc_layout_hdr(struct inode *inode, 450 gfp_t gfp_flags, bool is_scsi_layout) 451 { 452 struct pnfs_block_layout *bl; 453 454 dprintk("%s enter\n", __func__); 455 bl = kzalloc(sizeof(*bl), gfp_flags); 456 if (!bl) 457 return NULL; 458 459 bl->bl_ext_rw = RB_ROOT; 460 bl->bl_ext_ro = RB_ROOT; 461 spin_lock_init(&bl->bl_ext_lock); 462 463 bl->bl_scsi_layout = is_scsi_layout; 464 return &bl->bl_layout; 465 } 466 467 static struct pnfs_layout_hdr *bl_alloc_layout_hdr(struct inode *inode, 468 gfp_t gfp_flags) 469 { 470 return __bl_alloc_layout_hdr(inode, gfp_flags, false); 471 } 472 473 static struct pnfs_layout_hdr *sl_alloc_layout_hdr(struct inode *inode, 474 gfp_t gfp_flags) 475 { 476 return __bl_alloc_layout_hdr(inode, gfp_flags, true); 477 } 478 479 static void bl_free_lseg(struct pnfs_layout_segment *lseg) 480 { 481 dprintk("%s enter\n", __func__); 482 kfree(lseg); 483 } 484 485 /* Tracks info needed to ensure extents in layout obey constraints of spec */ 486 struct layout_verification { 487 u32 mode; /* R or RW */ 488 u64 start; /* Expected start of next non-COW extent */ 489 u64 inval; /* Start of INVAL coverage */ 490 u64 cowread; /* End of COW read coverage */ 491 }; 492 493 /* Verify the extent meets the layout requirements of the pnfs-block draft, 494 * section 2.3.1. 495 */ 496 static int verify_extent(struct pnfs_block_extent *be, 497 struct layout_verification *lv) 498 { 499 if (lv->mode == IOMODE_READ) { 500 if (be->be_state == PNFS_BLOCK_READWRITE_DATA || 501 be->be_state == PNFS_BLOCK_INVALID_DATA) 502 return -EIO; 503 if (be->be_f_offset != lv->start) 504 return -EIO; 505 lv->start += be->be_length; 506 return 0; 507 } 508 /* lv->mode == IOMODE_RW */ 509 if (be->be_state == PNFS_BLOCK_READWRITE_DATA) { 510 if (be->be_f_offset != lv->start) 511 return -EIO; 512 if (lv->cowread > lv->start) 513 return -EIO; 514 lv->start += be->be_length; 515 lv->inval = lv->start; 516 return 0; 517 } else if (be->be_state == PNFS_BLOCK_INVALID_DATA) { 518 if (be->be_f_offset != lv->start) 519 return -EIO; 520 lv->start += be->be_length; 521 return 0; 522 } else if (be->be_state == PNFS_BLOCK_READ_DATA) { 523 if (be->be_f_offset > lv->start) 524 return -EIO; 525 if (be->be_f_offset < lv->inval) 526 return -EIO; 527 if (be->be_f_offset < lv->cowread) 528 return -EIO; 529 /* It looks like you might want to min this with lv->start, 530 * but you really don't. 531 */ 532 lv->inval = lv->inval + be->be_length; 533 lv->cowread = be->be_f_offset + be->be_length; 534 return 0; 535 } else 536 return -EIO; 537 } 538 539 static int decode_sector_number(__be32 **rp, sector_t *sp) 540 { 541 uint64_t s; 542 543 *rp = xdr_decode_hyper(*rp, &s); 544 if (s & 0x1ff) { 545 printk(KERN_WARNING "NFS: %s: sector not aligned\n", __func__); 546 return -1; 547 } 548 *sp = s >> SECTOR_SHIFT; 549 return 0; 550 } 551 552 static int 553 bl_alloc_extent(struct xdr_stream *xdr, struct pnfs_layout_hdr *lo, 554 struct layout_verification *lv, struct list_head *extents, 555 gfp_t gfp_mask) 556 { 557 struct pnfs_block_extent *be; 558 struct nfs4_deviceid id; 559 int error; 560 __be32 *p; 561 562 p = xdr_inline_decode(xdr, 28 + NFS4_DEVICEID4_SIZE); 563 if (!p) 564 return -EIO; 565 566 be = kzalloc(sizeof(*be), GFP_NOFS); 567 if (!be) 568 return -ENOMEM; 569 570 memcpy(&id, p, NFS4_DEVICEID4_SIZE); 571 p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE); 572 573 error = -EIO; 574 be->be_device = nfs4_find_get_deviceid(NFS_SERVER(lo->plh_inode), &id, 575 lo->plh_lc_cred, gfp_mask); 576 if (!be->be_device) 577 goto out_free_be; 578 579 /* 580 * The next three values are read in as bytes, but stored in the 581 * extent structure in 512-byte granularity. 582 */ 583 if (decode_sector_number(&p, &be->be_f_offset) < 0) 584 goto out_put_deviceid; 585 if (decode_sector_number(&p, &be->be_length) < 0) 586 goto out_put_deviceid; 587 if (decode_sector_number(&p, &be->be_v_offset) < 0) 588 goto out_put_deviceid; 589 be->be_state = be32_to_cpup(p++); 590 591 error = verify_extent(be, lv); 592 if (error) { 593 dprintk("%s: extent verification failed\n", __func__); 594 goto out_put_deviceid; 595 } 596 597 list_add_tail(&be->be_list, extents); 598 return 0; 599 600 out_put_deviceid: 601 nfs4_put_deviceid_node(be->be_device); 602 out_free_be: 603 kfree(be); 604 return error; 605 } 606 607 static struct pnfs_layout_segment * 608 bl_alloc_lseg(struct pnfs_layout_hdr *lo, struct nfs4_layoutget_res *lgr, 609 gfp_t gfp_mask) 610 { 611 struct layout_verification lv = { 612 .mode = lgr->range.iomode, 613 .start = lgr->range.offset >> SECTOR_SHIFT, 614 .inval = lgr->range.offset >> SECTOR_SHIFT, 615 .cowread = lgr->range.offset >> SECTOR_SHIFT, 616 }; 617 struct pnfs_block_layout *bl = BLK_LO2EXT(lo); 618 struct pnfs_layout_segment *lseg; 619 struct xdr_buf buf; 620 struct xdr_stream xdr; 621 struct page *scratch; 622 int status, i; 623 uint32_t count; 624 __be32 *p; 625 LIST_HEAD(extents); 626 627 dprintk("---> %s\n", __func__); 628 629 lseg = kzalloc(sizeof(*lseg), gfp_mask); 630 if (!lseg) 631 return ERR_PTR(-ENOMEM); 632 633 status = -ENOMEM; 634 scratch = alloc_page(gfp_mask); 635 if (!scratch) 636 goto out; 637 638 xdr_init_decode_pages(&xdr, &buf, 639 lgr->layoutp->pages, lgr->layoutp->len); 640 xdr_set_scratch_buffer(&xdr, page_address(scratch), PAGE_SIZE); 641 642 status = -EIO; 643 p = xdr_inline_decode(&xdr, 4); 644 if (unlikely(!p)) 645 goto out_free_scratch; 646 647 count = be32_to_cpup(p++); 648 dprintk("%s: number of extents %d\n", __func__, count); 649 650 /* 651 * Decode individual extents, putting them in temporary staging area 652 * until whole layout is decoded to make error recovery easier. 653 */ 654 for (i = 0; i < count; i++) { 655 status = bl_alloc_extent(&xdr, lo, &lv, &extents, gfp_mask); 656 if (status) 657 goto process_extents; 658 } 659 660 if (lgr->range.offset + lgr->range.length != 661 lv.start << SECTOR_SHIFT) { 662 dprintk("%s Final length mismatch\n", __func__); 663 status = -EIO; 664 goto process_extents; 665 } 666 667 if (lv.start < lv.cowread) { 668 dprintk("%s Final uncovered COW extent\n", __func__); 669 status = -EIO; 670 } 671 672 process_extents: 673 while (!list_empty(&extents)) { 674 struct pnfs_block_extent *be = 675 list_first_entry(&extents, struct pnfs_block_extent, 676 be_list); 677 list_del(&be->be_list); 678 679 if (!status) 680 status = ext_tree_insert(bl, be); 681 682 if (status) { 683 nfs4_put_deviceid_node(be->be_device); 684 kfree(be); 685 } 686 } 687 688 out_free_scratch: 689 __free_page(scratch); 690 out: 691 dprintk("%s returns %d\n", __func__, status); 692 if (status) { 693 kfree(lseg); 694 return ERR_PTR(status); 695 } 696 return lseg; 697 } 698 699 static void 700 bl_return_range(struct pnfs_layout_hdr *lo, 701 struct pnfs_layout_range *range) 702 { 703 struct pnfs_block_layout *bl = BLK_LO2EXT(lo); 704 sector_t offset = range->offset >> SECTOR_SHIFT, end; 705 706 if (range->offset % 8) { 707 dprintk("%s: offset %lld not block size aligned\n", 708 __func__, range->offset); 709 return; 710 } 711 712 if (range->length != NFS4_MAX_UINT64) { 713 if (range->length % 8) { 714 dprintk("%s: length %lld not block size aligned\n", 715 __func__, range->length); 716 return; 717 } 718 719 end = offset + (range->length >> SECTOR_SHIFT); 720 } else { 721 end = round_down(NFS4_MAX_UINT64, PAGE_SIZE); 722 } 723 724 ext_tree_remove(bl, range->iomode & IOMODE_RW, offset, end); 725 } 726 727 static int 728 bl_prepare_layoutcommit(struct nfs4_layoutcommit_args *arg) 729 { 730 return ext_tree_prepare_commit(arg); 731 } 732 733 static void 734 bl_cleanup_layoutcommit(struct nfs4_layoutcommit_data *lcdata) 735 { 736 ext_tree_mark_committed(&lcdata->args, lcdata->res.status); 737 } 738 739 static int 740 bl_set_layoutdriver(struct nfs_server *server, const struct nfs_fh *fh) 741 { 742 dprintk("%s enter\n", __func__); 743 744 if (server->pnfs_blksize == 0) { 745 dprintk("%s Server did not return blksize\n", __func__); 746 return -EINVAL; 747 } 748 if (server->pnfs_blksize > PAGE_SIZE) { 749 printk(KERN_ERR "%s: pNFS blksize %d not supported.\n", 750 __func__, server->pnfs_blksize); 751 return -EINVAL; 752 } 753 754 return 0; 755 } 756 757 static bool 758 is_aligned_req(struct nfs_pageio_descriptor *pgio, 759 struct nfs_page *req, unsigned int alignment, bool is_write) 760 { 761 /* 762 * Always accept buffered writes, higher layers take care of the 763 * right alignment. 764 */ 765 if (pgio->pg_dreq == NULL) 766 return true; 767 768 if (!IS_ALIGNED(req->wb_offset, alignment)) 769 return false; 770 771 if (IS_ALIGNED(req->wb_bytes, alignment)) 772 return true; 773 774 if (is_write && 775 (req_offset(req) + req->wb_bytes == i_size_read(pgio->pg_inode))) { 776 /* 777 * If the write goes up to the inode size, just write 778 * the full page. Data past the inode size is 779 * guaranteed to be zeroed by the higher level client 780 * code, and this behaviour is mandated by RFC 5663 781 * section 2.3.2. 782 */ 783 return true; 784 } 785 786 return false; 787 } 788 789 static void 790 bl_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req) 791 { 792 if (!is_aligned_req(pgio, req, SECTOR_SIZE, false)) { 793 nfs_pageio_reset_read_mds(pgio); 794 return; 795 } 796 797 pnfs_generic_pg_init_read(pgio, req); 798 } 799 800 /* 801 * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number 802 * of bytes (maximum @req->wb_bytes) that can be coalesced. 803 */ 804 static size_t 805 bl_pg_test_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, 806 struct nfs_page *req) 807 { 808 if (!is_aligned_req(pgio, req, SECTOR_SIZE, false)) 809 return 0; 810 return pnfs_generic_pg_test(pgio, prev, req); 811 } 812 813 /* 814 * Return the number of contiguous bytes for a given inode 815 * starting at page frame idx. 816 */ 817 static u64 pnfs_num_cont_bytes(struct inode *inode, pgoff_t idx) 818 { 819 struct address_space *mapping = inode->i_mapping; 820 pgoff_t end; 821 822 /* Optimize common case that writes from 0 to end of file */ 823 end = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE); 824 if (end != inode->i_mapping->nrpages) { 825 rcu_read_lock(); 826 end = page_cache_next_hole(mapping, idx + 1, ULONG_MAX); 827 rcu_read_unlock(); 828 } 829 830 if (!end) 831 return i_size_read(inode) - (idx << PAGE_SHIFT); 832 else 833 return (end - idx) << PAGE_SHIFT; 834 } 835 836 static void 837 bl_pg_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *req) 838 { 839 u64 wb_size; 840 841 if (!is_aligned_req(pgio, req, PAGE_SIZE, true)) { 842 nfs_pageio_reset_write_mds(pgio); 843 return; 844 } 845 846 if (pgio->pg_dreq == NULL) 847 wb_size = pnfs_num_cont_bytes(pgio->pg_inode, 848 req->wb_index); 849 else 850 wb_size = nfs_dreq_bytes_left(pgio->pg_dreq); 851 852 pnfs_generic_pg_init_write(pgio, req, wb_size); 853 } 854 855 /* 856 * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number 857 * of bytes (maximum @req->wb_bytes) that can be coalesced. 858 */ 859 static size_t 860 bl_pg_test_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, 861 struct nfs_page *req) 862 { 863 if (!is_aligned_req(pgio, req, PAGE_SIZE, true)) 864 return 0; 865 return pnfs_generic_pg_test(pgio, prev, req); 866 } 867 868 static const struct nfs_pageio_ops bl_pg_read_ops = { 869 .pg_init = bl_pg_init_read, 870 .pg_test = bl_pg_test_read, 871 .pg_doio = pnfs_generic_pg_readpages, 872 .pg_cleanup = pnfs_generic_pg_cleanup, 873 }; 874 875 static const struct nfs_pageio_ops bl_pg_write_ops = { 876 .pg_init = bl_pg_init_write, 877 .pg_test = bl_pg_test_write, 878 .pg_doio = pnfs_generic_pg_writepages, 879 .pg_cleanup = pnfs_generic_pg_cleanup, 880 }; 881 882 static struct pnfs_layoutdriver_type blocklayout_type = { 883 .id = LAYOUT_BLOCK_VOLUME, 884 .name = "LAYOUT_BLOCK_VOLUME", 885 .owner = THIS_MODULE, 886 .flags = PNFS_LAYOUTRET_ON_SETATTR | 887 PNFS_READ_WHOLE_PAGE, 888 .read_pagelist = bl_read_pagelist, 889 .write_pagelist = bl_write_pagelist, 890 .alloc_layout_hdr = bl_alloc_layout_hdr, 891 .free_layout_hdr = bl_free_layout_hdr, 892 .alloc_lseg = bl_alloc_lseg, 893 .free_lseg = bl_free_lseg, 894 .return_range = bl_return_range, 895 .prepare_layoutcommit = bl_prepare_layoutcommit, 896 .cleanup_layoutcommit = bl_cleanup_layoutcommit, 897 .set_layoutdriver = bl_set_layoutdriver, 898 .alloc_deviceid_node = bl_alloc_deviceid_node, 899 .free_deviceid_node = bl_free_deviceid_node, 900 .pg_read_ops = &bl_pg_read_ops, 901 .pg_write_ops = &bl_pg_write_ops, 902 .sync = pnfs_generic_sync, 903 }; 904 905 static struct pnfs_layoutdriver_type scsilayout_type = { 906 .id = LAYOUT_SCSI, 907 .name = "LAYOUT_SCSI", 908 .owner = THIS_MODULE, 909 .flags = PNFS_LAYOUTRET_ON_SETATTR | 910 PNFS_READ_WHOLE_PAGE, 911 .read_pagelist = bl_read_pagelist, 912 .write_pagelist = bl_write_pagelist, 913 .alloc_layout_hdr = sl_alloc_layout_hdr, 914 .free_layout_hdr = bl_free_layout_hdr, 915 .alloc_lseg = bl_alloc_lseg, 916 .free_lseg = bl_free_lseg, 917 .return_range = bl_return_range, 918 .prepare_layoutcommit = bl_prepare_layoutcommit, 919 .cleanup_layoutcommit = bl_cleanup_layoutcommit, 920 .set_layoutdriver = bl_set_layoutdriver, 921 .alloc_deviceid_node = bl_alloc_deviceid_node, 922 .free_deviceid_node = bl_free_deviceid_node, 923 .pg_read_ops = &bl_pg_read_ops, 924 .pg_write_ops = &bl_pg_write_ops, 925 .sync = pnfs_generic_sync, 926 }; 927 928 929 static int __init nfs4blocklayout_init(void) 930 { 931 int ret; 932 933 dprintk("%s: NFSv4 Block Layout Driver Registering...\n", __func__); 934 935 ret = bl_init_pipefs(); 936 if (ret) 937 goto out; 938 939 ret = pnfs_register_layoutdriver(&blocklayout_type); 940 if (ret) 941 goto out_cleanup_pipe; 942 943 ret = pnfs_register_layoutdriver(&scsilayout_type); 944 if (ret) 945 goto out_unregister_block; 946 return 0; 947 948 out_unregister_block: 949 pnfs_unregister_layoutdriver(&blocklayout_type); 950 out_cleanup_pipe: 951 bl_cleanup_pipefs(); 952 out: 953 return ret; 954 } 955 956 static void __exit nfs4blocklayout_exit(void) 957 { 958 dprintk("%s: NFSv4 Block Layout Driver Unregistering...\n", 959 __func__); 960 961 pnfs_unregister_layoutdriver(&scsilayout_type); 962 pnfs_unregister_layoutdriver(&blocklayout_type); 963 bl_cleanup_pipefs(); 964 } 965 966 MODULE_ALIAS("nfs-layouttype4-3"); 967 968 module_init(nfs4blocklayout_init); 969 module_exit(nfs4blocklayout_exit); 970