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(struct bio *bio) 106 { 107 if (bio) { 108 get_parallel(bio->bi_private); 109 dprintk("%s submitting %s bio %u@%llu\n", __func__, 110 bio_op(bio) == READ ? "read" : "write", 111 bio->bi_iter.bi_size, 112 (unsigned long long)bio->bi_iter.bi_sector); 113 submit_bio(bio); 114 } 115 return NULL; 116 } 117 118 static struct bio * 119 bl_alloc_init_bio(int npg, struct block_device *bdev, sector_t disk_sector, 120 bio_end_io_t end_io, struct parallel_io *par) 121 { 122 struct bio *bio; 123 124 npg = min(npg, BIO_MAX_PAGES); 125 bio = bio_alloc(GFP_NOIO, npg); 126 if (!bio && (current->flags & PF_MEMALLOC)) { 127 while (!bio && (npg /= 2)) 128 bio = bio_alloc(GFP_NOIO, npg); 129 } 130 131 if (bio) { 132 bio->bi_iter.bi_sector = disk_sector; 133 bio_set_dev(bio, bdev); 134 bio->bi_end_io = end_io; 135 bio->bi_private = par; 136 } 137 return bio; 138 } 139 140 static bool offset_in_map(u64 offset, struct pnfs_block_dev_map *map) 141 { 142 return offset >= map->start && offset < map->start + map->len; 143 } 144 145 static struct bio * 146 do_add_page_to_bio(struct bio *bio, int npg, int rw, sector_t isect, 147 struct page *page, struct pnfs_block_dev_map *map, 148 struct pnfs_block_extent *be, bio_end_io_t end_io, 149 struct parallel_io *par, unsigned int offset, int *len) 150 { 151 struct pnfs_block_dev *dev = 152 container_of(be->be_device, struct pnfs_block_dev, node); 153 u64 disk_addr, end; 154 155 dprintk("%s: npg %d rw %d isect %llu offset %u len %d\n", __func__, 156 npg, rw, (unsigned long long)isect, offset, *len); 157 158 /* translate to device offset */ 159 isect += be->be_v_offset; 160 isect -= be->be_f_offset; 161 162 /* translate to physical disk offset */ 163 disk_addr = (u64)isect << SECTOR_SHIFT; 164 if (!offset_in_map(disk_addr, map)) { 165 if (!dev->map(dev, disk_addr, map) || !offset_in_map(disk_addr, map)) 166 return ERR_PTR(-EIO); 167 bio = bl_submit_bio(bio); 168 } 169 disk_addr += map->disk_offset; 170 disk_addr -= map->start; 171 172 /* limit length to what the device mapping allows */ 173 end = disk_addr + *len; 174 if (end >= map->start + map->len) 175 *len = map->start + map->len - disk_addr; 176 177 retry: 178 if (!bio) { 179 bio = bl_alloc_init_bio(npg, map->bdev, 180 disk_addr >> SECTOR_SHIFT, end_io, par); 181 if (!bio) 182 return ERR_PTR(-ENOMEM); 183 bio_set_op_attrs(bio, rw, 0); 184 } 185 if (bio_add_page(bio, page, *len, offset) < *len) { 186 bio = bl_submit_bio(bio); 187 goto retry; 188 } 189 return bio; 190 } 191 192 static void bl_mark_devices_unavailable(struct nfs_pgio_header *header, bool rw) 193 { 194 struct pnfs_block_layout *bl = BLK_LSEG2EXT(header->lseg); 195 size_t bytes_left = header->args.count; 196 sector_t isect, extent_length = 0; 197 struct pnfs_block_extent be; 198 199 isect = header->args.offset >> SECTOR_SHIFT; 200 bytes_left += header->args.offset - (isect << SECTOR_SHIFT); 201 202 while (bytes_left > 0) { 203 if (!ext_tree_lookup(bl, isect, &be, rw)) 204 return; 205 extent_length = be.be_length - (isect - be.be_f_offset); 206 nfs4_mark_deviceid_unavailable(be.be_device); 207 isect += extent_length; 208 if (bytes_left > extent_length << SECTOR_SHIFT) 209 bytes_left -= extent_length << SECTOR_SHIFT; 210 else 211 bytes_left = 0; 212 } 213 } 214 215 static void bl_end_io_read(struct bio *bio) 216 { 217 struct parallel_io *par = bio->bi_private; 218 219 if (bio->bi_status) { 220 struct nfs_pgio_header *header = par->data; 221 222 if (!header->pnfs_error) 223 header->pnfs_error = -EIO; 224 pnfs_set_lo_fail(header->lseg); 225 bl_mark_devices_unavailable(header, false); 226 } 227 228 bio_put(bio); 229 put_parallel(par); 230 } 231 232 static void bl_read_cleanup(struct work_struct *work) 233 { 234 struct rpc_task *task; 235 struct nfs_pgio_header *hdr; 236 dprintk("%s enter\n", __func__); 237 task = container_of(work, struct rpc_task, u.tk_work); 238 hdr = container_of(task, struct nfs_pgio_header, task); 239 pnfs_ld_read_done(hdr); 240 } 241 242 static void 243 bl_end_par_io_read(void *data) 244 { 245 struct nfs_pgio_header *hdr = data; 246 247 hdr->task.tk_status = hdr->pnfs_error; 248 INIT_WORK(&hdr->task.u.tk_work, bl_read_cleanup); 249 schedule_work(&hdr->task.u.tk_work); 250 } 251 252 static enum pnfs_try_status 253 bl_read_pagelist(struct nfs_pgio_header *header) 254 { 255 struct pnfs_block_layout *bl = BLK_LSEG2EXT(header->lseg); 256 struct pnfs_block_dev_map map = { .start = NFS4_MAX_UINT64 }; 257 struct bio *bio = NULL; 258 struct pnfs_block_extent be; 259 sector_t isect, extent_length = 0; 260 struct parallel_io *par; 261 loff_t f_offset = header->args.offset; 262 size_t bytes_left = header->args.count; 263 unsigned int pg_offset = header->args.pgbase, pg_len; 264 struct page **pages = header->args.pages; 265 int pg_index = header->args.pgbase >> PAGE_SHIFT; 266 const bool is_dio = (header->dreq != NULL); 267 struct blk_plug plug; 268 int i; 269 270 dprintk("%s enter nr_pages %u offset %lld count %u\n", __func__, 271 header->page_array.npages, f_offset, 272 (unsigned int)header->args.count); 273 274 par = alloc_parallel(header); 275 if (!par) 276 return PNFS_NOT_ATTEMPTED; 277 par->pnfs_callback = bl_end_par_io_read; 278 279 blk_start_plug(&plug); 280 281 isect = (sector_t) (f_offset >> SECTOR_SHIFT); 282 /* Code assumes extents are page-aligned */ 283 for (i = pg_index; i < header->page_array.npages; i++) { 284 if (extent_length <= 0) { 285 /* We've used up the previous extent */ 286 bio = bl_submit_bio(bio); 287 288 /* Get the next one */ 289 if (!ext_tree_lookup(bl, isect, &be, false)) { 290 header->pnfs_error = -EIO; 291 goto out; 292 } 293 extent_length = be.be_length - (isect - be.be_f_offset); 294 } 295 296 if (is_dio) { 297 if (pg_offset + bytes_left > PAGE_SIZE) 298 pg_len = PAGE_SIZE - pg_offset; 299 else 300 pg_len = bytes_left; 301 } else { 302 BUG_ON(pg_offset != 0); 303 pg_len = PAGE_SIZE; 304 } 305 306 if (is_hole(&be)) { 307 bio = bl_submit_bio(bio); 308 /* Fill hole w/ zeroes w/o accessing device */ 309 dprintk("%s Zeroing page for hole\n", __func__); 310 zero_user_segment(pages[i], pg_offset, pg_len); 311 312 /* invalidate map */ 313 map.start = NFS4_MAX_UINT64; 314 } else { 315 bio = do_add_page_to_bio(bio, 316 header->page_array.npages - i, 317 READ, 318 isect, pages[i], &map, &be, 319 bl_end_io_read, par, 320 pg_offset, &pg_len); 321 if (IS_ERR(bio)) { 322 header->pnfs_error = PTR_ERR(bio); 323 bio = NULL; 324 goto out; 325 } 326 } 327 isect += (pg_len >> SECTOR_SHIFT); 328 extent_length -= (pg_len >> SECTOR_SHIFT); 329 f_offset += pg_len; 330 bytes_left -= pg_len; 331 pg_offset = 0; 332 } 333 if ((isect << SECTOR_SHIFT) >= header->inode->i_size) { 334 header->res.eof = 1; 335 header->res.count = header->inode->i_size - header->args.offset; 336 } else { 337 header->res.count = (isect << SECTOR_SHIFT) - header->args.offset; 338 } 339 out: 340 bl_submit_bio(bio); 341 blk_finish_plug(&plug); 342 put_parallel(par); 343 return PNFS_ATTEMPTED; 344 } 345 346 static void bl_end_io_write(struct bio *bio) 347 { 348 struct parallel_io *par = bio->bi_private; 349 struct nfs_pgio_header *header = par->data; 350 351 if (bio->bi_status) { 352 if (!header->pnfs_error) 353 header->pnfs_error = -EIO; 354 pnfs_set_lo_fail(header->lseg); 355 bl_mark_devices_unavailable(header, true); 356 } 357 bio_put(bio); 358 put_parallel(par); 359 } 360 361 /* Function scheduled for call during bl_end_par_io_write, 362 * it marks sectors as written and extends the commitlist. 363 */ 364 static void bl_write_cleanup(struct work_struct *work) 365 { 366 struct rpc_task *task = container_of(work, struct rpc_task, u.tk_work); 367 struct nfs_pgio_header *hdr = 368 container_of(task, struct nfs_pgio_header, task); 369 370 dprintk("%s enter\n", __func__); 371 372 if (likely(!hdr->pnfs_error)) { 373 struct pnfs_block_layout *bl = BLK_LSEG2EXT(hdr->lseg); 374 u64 start = hdr->args.offset & (loff_t)PAGE_MASK; 375 u64 end = (hdr->args.offset + hdr->args.count + 376 PAGE_SIZE - 1) & (loff_t)PAGE_MASK; 377 u64 lwb = hdr->args.offset + hdr->args.count; 378 379 ext_tree_mark_written(bl, start >> SECTOR_SHIFT, 380 (end - start) >> SECTOR_SHIFT, lwb); 381 } 382 383 pnfs_ld_write_done(hdr); 384 } 385 386 /* Called when last of bios associated with a bl_write_pagelist call finishes */ 387 static void bl_end_par_io_write(void *data) 388 { 389 struct nfs_pgio_header *hdr = data; 390 391 hdr->task.tk_status = hdr->pnfs_error; 392 hdr->verf.committed = NFS_FILE_SYNC; 393 INIT_WORK(&hdr->task.u.tk_work, bl_write_cleanup); 394 schedule_work(&hdr->task.u.tk_work); 395 } 396 397 static enum pnfs_try_status 398 bl_write_pagelist(struct nfs_pgio_header *header, int sync) 399 { 400 struct pnfs_block_layout *bl = BLK_LSEG2EXT(header->lseg); 401 struct pnfs_block_dev_map map = { .start = NFS4_MAX_UINT64 }; 402 struct bio *bio = NULL; 403 struct pnfs_block_extent be; 404 sector_t isect, extent_length = 0; 405 struct parallel_io *par = NULL; 406 loff_t offset = header->args.offset; 407 size_t count = header->args.count; 408 struct page **pages = header->args.pages; 409 int pg_index = header->args.pgbase >> PAGE_SHIFT; 410 unsigned int pg_len; 411 struct blk_plug plug; 412 int i; 413 414 dprintk("%s enter, %zu@%lld\n", __func__, count, offset); 415 416 /* At this point, header->page_aray is a (sequential) list of nfs_pages. 417 * We want to write each, and if there is an error set pnfs_error 418 * to have it redone using nfs. 419 */ 420 par = alloc_parallel(header); 421 if (!par) 422 return PNFS_NOT_ATTEMPTED; 423 par->pnfs_callback = bl_end_par_io_write; 424 425 blk_start_plug(&plug); 426 427 /* we always write out the whole page */ 428 offset = offset & (loff_t)PAGE_MASK; 429 isect = offset >> SECTOR_SHIFT; 430 431 for (i = pg_index; i < header->page_array.npages; i++) { 432 if (extent_length <= 0) { 433 /* We've used up the previous extent */ 434 bio = bl_submit_bio(bio); 435 /* Get the next one */ 436 if (!ext_tree_lookup(bl, isect, &be, true)) { 437 header->pnfs_error = -EINVAL; 438 goto out; 439 } 440 441 extent_length = be.be_length - (isect - be.be_f_offset); 442 } 443 444 pg_len = PAGE_SIZE; 445 bio = do_add_page_to_bio(bio, header->page_array.npages - i, 446 WRITE, isect, pages[i], &map, &be, 447 bl_end_io_write, par, 448 0, &pg_len); 449 if (IS_ERR(bio)) { 450 header->pnfs_error = PTR_ERR(bio); 451 bio = NULL; 452 goto out; 453 } 454 455 offset += pg_len; 456 count -= pg_len; 457 isect += (pg_len >> SECTOR_SHIFT); 458 extent_length -= (pg_len >> SECTOR_SHIFT); 459 } 460 461 header->res.count = header->args.count; 462 out: 463 bl_submit_bio(bio); 464 blk_finish_plug(&plug); 465 put_parallel(par); 466 return PNFS_ATTEMPTED; 467 } 468 469 static void bl_free_layout_hdr(struct pnfs_layout_hdr *lo) 470 { 471 struct pnfs_block_layout *bl = BLK_LO2EXT(lo); 472 int err; 473 474 dprintk("%s enter\n", __func__); 475 476 err = ext_tree_remove(bl, true, 0, LLONG_MAX); 477 WARN_ON(err); 478 479 kfree_rcu(bl, bl_layout.plh_rcu); 480 } 481 482 static struct pnfs_layout_hdr *__bl_alloc_layout_hdr(struct inode *inode, 483 gfp_t gfp_flags, bool is_scsi_layout) 484 { 485 struct pnfs_block_layout *bl; 486 487 dprintk("%s enter\n", __func__); 488 bl = kzalloc(sizeof(*bl), gfp_flags); 489 if (!bl) 490 return NULL; 491 492 bl->bl_ext_rw = RB_ROOT; 493 bl->bl_ext_ro = RB_ROOT; 494 spin_lock_init(&bl->bl_ext_lock); 495 496 bl->bl_scsi_layout = is_scsi_layout; 497 return &bl->bl_layout; 498 } 499 500 static struct pnfs_layout_hdr *bl_alloc_layout_hdr(struct inode *inode, 501 gfp_t gfp_flags) 502 { 503 return __bl_alloc_layout_hdr(inode, gfp_flags, false); 504 } 505 506 static struct pnfs_layout_hdr *sl_alloc_layout_hdr(struct inode *inode, 507 gfp_t gfp_flags) 508 { 509 return __bl_alloc_layout_hdr(inode, gfp_flags, true); 510 } 511 512 static void bl_free_lseg(struct pnfs_layout_segment *lseg) 513 { 514 dprintk("%s enter\n", __func__); 515 kfree(lseg); 516 } 517 518 /* Tracks info needed to ensure extents in layout obey constraints of spec */ 519 struct layout_verification { 520 u32 mode; /* R or RW */ 521 u64 start; /* Expected start of next non-COW extent */ 522 u64 inval; /* Start of INVAL coverage */ 523 u64 cowread; /* End of COW read coverage */ 524 }; 525 526 /* Verify the extent meets the layout requirements of the pnfs-block draft, 527 * section 2.3.1. 528 */ 529 static int verify_extent(struct pnfs_block_extent *be, 530 struct layout_verification *lv) 531 { 532 if (lv->mode == IOMODE_READ) { 533 if (be->be_state == PNFS_BLOCK_READWRITE_DATA || 534 be->be_state == PNFS_BLOCK_INVALID_DATA) 535 return -EIO; 536 if (be->be_f_offset != lv->start) 537 return -EIO; 538 lv->start += be->be_length; 539 return 0; 540 } 541 /* lv->mode == IOMODE_RW */ 542 if (be->be_state == PNFS_BLOCK_READWRITE_DATA) { 543 if (be->be_f_offset != lv->start) 544 return -EIO; 545 if (lv->cowread > lv->start) 546 return -EIO; 547 lv->start += be->be_length; 548 lv->inval = lv->start; 549 return 0; 550 } else if (be->be_state == PNFS_BLOCK_INVALID_DATA) { 551 if (be->be_f_offset != lv->start) 552 return -EIO; 553 lv->start += be->be_length; 554 return 0; 555 } else if (be->be_state == PNFS_BLOCK_READ_DATA) { 556 if (be->be_f_offset > lv->start) 557 return -EIO; 558 if (be->be_f_offset < lv->inval) 559 return -EIO; 560 if (be->be_f_offset < lv->cowread) 561 return -EIO; 562 /* It looks like you might want to min this with lv->start, 563 * but you really don't. 564 */ 565 lv->inval = lv->inval + be->be_length; 566 lv->cowread = be->be_f_offset + be->be_length; 567 return 0; 568 } else 569 return -EIO; 570 } 571 572 static int decode_sector_number(__be32 **rp, sector_t *sp) 573 { 574 uint64_t s; 575 576 *rp = xdr_decode_hyper(*rp, &s); 577 if (s & 0x1ff) { 578 printk(KERN_WARNING "NFS: %s: sector not aligned\n", __func__); 579 return -1; 580 } 581 *sp = s >> SECTOR_SHIFT; 582 return 0; 583 } 584 585 static struct nfs4_deviceid_node * 586 bl_find_get_deviceid(struct nfs_server *server, 587 const struct nfs4_deviceid *id, const struct cred *cred, 588 gfp_t gfp_mask) 589 { 590 struct nfs4_deviceid_node *node; 591 unsigned long start, end; 592 593 retry: 594 node = nfs4_find_get_deviceid(server, id, cred, gfp_mask); 595 if (!node) 596 return ERR_PTR(-ENODEV); 597 598 if (test_bit(NFS_DEVICEID_UNAVAILABLE, &node->flags) == 0) 599 return node; 600 601 end = jiffies; 602 start = end - PNFS_DEVICE_RETRY_TIMEOUT; 603 if (!time_in_range(node->timestamp_unavailable, start, end)) { 604 nfs4_delete_deviceid(node->ld, node->nfs_client, id); 605 goto retry; 606 } 607 return ERR_PTR(-ENODEV); 608 } 609 610 static int 611 bl_alloc_extent(struct xdr_stream *xdr, struct pnfs_layout_hdr *lo, 612 struct layout_verification *lv, struct list_head *extents, 613 gfp_t gfp_mask) 614 { 615 struct pnfs_block_extent *be; 616 struct nfs4_deviceid id; 617 int error; 618 __be32 *p; 619 620 p = xdr_inline_decode(xdr, 28 + NFS4_DEVICEID4_SIZE); 621 if (!p) 622 return -EIO; 623 624 be = kzalloc(sizeof(*be), GFP_NOFS); 625 if (!be) 626 return -ENOMEM; 627 628 memcpy(&id, p, NFS4_DEVICEID4_SIZE); 629 p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE); 630 631 be->be_device = bl_find_get_deviceid(NFS_SERVER(lo->plh_inode), &id, 632 lo->plh_lc_cred, gfp_mask); 633 if (IS_ERR(be->be_device)) { 634 error = PTR_ERR(be->be_device); 635 goto out_free_be; 636 } 637 638 /* 639 * The next three values are read in as bytes, but stored in the 640 * extent structure in 512-byte granularity. 641 */ 642 error = -EIO; 643 if (decode_sector_number(&p, &be->be_f_offset) < 0) 644 goto out_put_deviceid; 645 if (decode_sector_number(&p, &be->be_length) < 0) 646 goto out_put_deviceid; 647 if (decode_sector_number(&p, &be->be_v_offset) < 0) 648 goto out_put_deviceid; 649 be->be_state = be32_to_cpup(p++); 650 651 error = verify_extent(be, lv); 652 if (error) { 653 dprintk("%s: extent verification failed\n", __func__); 654 goto out_put_deviceid; 655 } 656 657 list_add_tail(&be->be_list, extents); 658 return 0; 659 660 out_put_deviceid: 661 nfs4_put_deviceid_node(be->be_device); 662 out_free_be: 663 kfree(be); 664 return error; 665 } 666 667 static struct pnfs_layout_segment * 668 bl_alloc_lseg(struct pnfs_layout_hdr *lo, struct nfs4_layoutget_res *lgr, 669 gfp_t gfp_mask) 670 { 671 struct layout_verification lv = { 672 .mode = lgr->range.iomode, 673 .start = lgr->range.offset >> SECTOR_SHIFT, 674 .inval = lgr->range.offset >> SECTOR_SHIFT, 675 .cowread = lgr->range.offset >> SECTOR_SHIFT, 676 }; 677 struct pnfs_block_layout *bl = BLK_LO2EXT(lo); 678 struct pnfs_layout_segment *lseg; 679 struct xdr_buf buf; 680 struct xdr_stream xdr; 681 struct page *scratch; 682 int status, i; 683 uint32_t count; 684 __be32 *p; 685 LIST_HEAD(extents); 686 687 dprintk("---> %s\n", __func__); 688 689 lseg = kzalloc(sizeof(*lseg), gfp_mask); 690 if (!lseg) 691 return ERR_PTR(-ENOMEM); 692 693 status = -ENOMEM; 694 scratch = alloc_page(gfp_mask); 695 if (!scratch) 696 goto out; 697 698 xdr_init_decode_pages(&xdr, &buf, 699 lgr->layoutp->pages, lgr->layoutp->len); 700 xdr_set_scratch_page(&xdr, scratch); 701 702 status = -EIO; 703 p = xdr_inline_decode(&xdr, 4); 704 if (unlikely(!p)) 705 goto out_free_scratch; 706 707 count = be32_to_cpup(p++); 708 dprintk("%s: number of extents %d\n", __func__, count); 709 710 /* 711 * Decode individual extents, putting them in temporary staging area 712 * until whole layout is decoded to make error recovery easier. 713 */ 714 for (i = 0; i < count; i++) { 715 status = bl_alloc_extent(&xdr, lo, &lv, &extents, gfp_mask); 716 if (status) 717 goto process_extents; 718 } 719 720 if (lgr->range.offset + lgr->range.length != 721 lv.start << SECTOR_SHIFT) { 722 dprintk("%s Final length mismatch\n", __func__); 723 status = -EIO; 724 goto process_extents; 725 } 726 727 if (lv.start < lv.cowread) { 728 dprintk("%s Final uncovered COW extent\n", __func__); 729 status = -EIO; 730 } 731 732 process_extents: 733 while (!list_empty(&extents)) { 734 struct pnfs_block_extent *be = 735 list_first_entry(&extents, struct pnfs_block_extent, 736 be_list); 737 list_del(&be->be_list); 738 739 if (!status) 740 status = ext_tree_insert(bl, be); 741 742 if (status) { 743 nfs4_put_deviceid_node(be->be_device); 744 kfree(be); 745 } 746 } 747 748 out_free_scratch: 749 __free_page(scratch); 750 out: 751 dprintk("%s returns %d\n", __func__, status); 752 switch (status) { 753 case -ENODEV: 754 /* Our extent block devices are unavailable */ 755 set_bit(NFS_LSEG_UNAVAILABLE, &lseg->pls_flags); 756 fallthrough; 757 case 0: 758 return lseg; 759 default: 760 kfree(lseg); 761 return ERR_PTR(status); 762 } 763 } 764 765 static void 766 bl_return_range(struct pnfs_layout_hdr *lo, 767 struct pnfs_layout_range *range) 768 { 769 struct pnfs_block_layout *bl = BLK_LO2EXT(lo); 770 sector_t offset = range->offset >> SECTOR_SHIFT, end; 771 772 if (range->offset % 8) { 773 dprintk("%s: offset %lld not block size aligned\n", 774 __func__, range->offset); 775 return; 776 } 777 778 if (range->length != NFS4_MAX_UINT64) { 779 if (range->length % 8) { 780 dprintk("%s: length %lld not block size aligned\n", 781 __func__, range->length); 782 return; 783 } 784 785 end = offset + (range->length >> SECTOR_SHIFT); 786 } else { 787 end = round_down(NFS4_MAX_UINT64, PAGE_SIZE); 788 } 789 790 ext_tree_remove(bl, range->iomode & IOMODE_RW, offset, end); 791 } 792 793 static int 794 bl_prepare_layoutcommit(struct nfs4_layoutcommit_args *arg) 795 { 796 return ext_tree_prepare_commit(arg); 797 } 798 799 static void 800 bl_cleanup_layoutcommit(struct nfs4_layoutcommit_data *lcdata) 801 { 802 ext_tree_mark_committed(&lcdata->args, lcdata->res.status); 803 } 804 805 static int 806 bl_set_layoutdriver(struct nfs_server *server, const struct nfs_fh *fh) 807 { 808 dprintk("%s enter\n", __func__); 809 810 if (server->pnfs_blksize == 0) { 811 dprintk("%s Server did not return blksize\n", __func__); 812 return -EINVAL; 813 } 814 if (server->pnfs_blksize > PAGE_SIZE) { 815 printk(KERN_ERR "%s: pNFS blksize %d not supported.\n", 816 __func__, server->pnfs_blksize); 817 return -EINVAL; 818 } 819 820 return 0; 821 } 822 823 static bool 824 is_aligned_req(struct nfs_pageio_descriptor *pgio, 825 struct nfs_page *req, unsigned int alignment, bool is_write) 826 { 827 /* 828 * Always accept buffered writes, higher layers take care of the 829 * right alignment. 830 */ 831 if (pgio->pg_dreq == NULL) 832 return true; 833 834 if (!IS_ALIGNED(req->wb_offset, alignment)) 835 return false; 836 837 if (IS_ALIGNED(req->wb_bytes, alignment)) 838 return true; 839 840 if (is_write && 841 (req_offset(req) + req->wb_bytes == i_size_read(pgio->pg_inode))) { 842 /* 843 * If the write goes up to the inode size, just write 844 * the full page. Data past the inode size is 845 * guaranteed to be zeroed by the higher level client 846 * code, and this behaviour is mandated by RFC 5663 847 * section 2.3.2. 848 */ 849 return true; 850 } 851 852 return false; 853 } 854 855 static void 856 bl_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req) 857 { 858 if (!is_aligned_req(pgio, req, SECTOR_SIZE, false)) { 859 nfs_pageio_reset_read_mds(pgio); 860 return; 861 } 862 863 pnfs_generic_pg_init_read(pgio, req); 864 865 if (pgio->pg_lseg && 866 test_bit(NFS_LSEG_UNAVAILABLE, &pgio->pg_lseg->pls_flags)) { 867 pnfs_error_mark_layout_for_return(pgio->pg_inode, pgio->pg_lseg); 868 pnfs_set_lo_fail(pgio->pg_lseg); 869 nfs_pageio_reset_read_mds(pgio); 870 } 871 } 872 873 /* 874 * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number 875 * of bytes (maximum @req->wb_bytes) that can be coalesced. 876 */ 877 static size_t 878 bl_pg_test_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, 879 struct nfs_page *req) 880 { 881 if (!is_aligned_req(pgio, req, SECTOR_SIZE, false)) 882 return 0; 883 return pnfs_generic_pg_test(pgio, prev, req); 884 } 885 886 /* 887 * Return the number of contiguous bytes for a given inode 888 * starting at page frame idx. 889 */ 890 static u64 pnfs_num_cont_bytes(struct inode *inode, pgoff_t idx) 891 { 892 struct address_space *mapping = inode->i_mapping; 893 pgoff_t end; 894 895 /* Optimize common case that writes from 0 to end of file */ 896 end = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE); 897 if (end != inode->i_mapping->nrpages) { 898 rcu_read_lock(); 899 end = page_cache_next_miss(mapping, idx + 1, ULONG_MAX); 900 rcu_read_unlock(); 901 } 902 903 if (!end) 904 return i_size_read(inode) - (idx << PAGE_SHIFT); 905 else 906 return (end - idx) << PAGE_SHIFT; 907 } 908 909 static void 910 bl_pg_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *req) 911 { 912 u64 wb_size; 913 914 if (!is_aligned_req(pgio, req, PAGE_SIZE, true)) { 915 nfs_pageio_reset_write_mds(pgio); 916 return; 917 } 918 919 if (pgio->pg_dreq == NULL) 920 wb_size = pnfs_num_cont_bytes(pgio->pg_inode, 921 req->wb_index); 922 else 923 wb_size = nfs_dreq_bytes_left(pgio->pg_dreq); 924 925 pnfs_generic_pg_init_write(pgio, req, wb_size); 926 927 if (pgio->pg_lseg && 928 test_bit(NFS_LSEG_UNAVAILABLE, &pgio->pg_lseg->pls_flags)) { 929 930 pnfs_error_mark_layout_for_return(pgio->pg_inode, pgio->pg_lseg); 931 pnfs_set_lo_fail(pgio->pg_lseg); 932 nfs_pageio_reset_write_mds(pgio); 933 } 934 } 935 936 /* 937 * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number 938 * of bytes (maximum @req->wb_bytes) that can be coalesced. 939 */ 940 static size_t 941 bl_pg_test_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, 942 struct nfs_page *req) 943 { 944 if (!is_aligned_req(pgio, req, PAGE_SIZE, true)) 945 return 0; 946 return pnfs_generic_pg_test(pgio, prev, req); 947 } 948 949 static const struct nfs_pageio_ops bl_pg_read_ops = { 950 .pg_init = bl_pg_init_read, 951 .pg_test = bl_pg_test_read, 952 .pg_doio = pnfs_generic_pg_readpages, 953 .pg_cleanup = pnfs_generic_pg_cleanup, 954 }; 955 956 static const struct nfs_pageio_ops bl_pg_write_ops = { 957 .pg_init = bl_pg_init_write, 958 .pg_test = bl_pg_test_write, 959 .pg_doio = pnfs_generic_pg_writepages, 960 .pg_cleanup = pnfs_generic_pg_cleanup, 961 }; 962 963 static struct pnfs_layoutdriver_type blocklayout_type = { 964 .id = LAYOUT_BLOCK_VOLUME, 965 .name = "LAYOUT_BLOCK_VOLUME", 966 .owner = THIS_MODULE, 967 .flags = PNFS_LAYOUTRET_ON_SETATTR | 968 PNFS_LAYOUTRET_ON_ERROR | 969 PNFS_READ_WHOLE_PAGE, 970 .read_pagelist = bl_read_pagelist, 971 .write_pagelist = bl_write_pagelist, 972 .alloc_layout_hdr = bl_alloc_layout_hdr, 973 .free_layout_hdr = bl_free_layout_hdr, 974 .alloc_lseg = bl_alloc_lseg, 975 .free_lseg = bl_free_lseg, 976 .return_range = bl_return_range, 977 .prepare_layoutcommit = bl_prepare_layoutcommit, 978 .cleanup_layoutcommit = bl_cleanup_layoutcommit, 979 .set_layoutdriver = bl_set_layoutdriver, 980 .alloc_deviceid_node = bl_alloc_deviceid_node, 981 .free_deviceid_node = bl_free_deviceid_node, 982 .pg_read_ops = &bl_pg_read_ops, 983 .pg_write_ops = &bl_pg_write_ops, 984 .sync = pnfs_generic_sync, 985 }; 986 987 static struct pnfs_layoutdriver_type scsilayout_type = { 988 .id = LAYOUT_SCSI, 989 .name = "LAYOUT_SCSI", 990 .owner = THIS_MODULE, 991 .flags = PNFS_LAYOUTRET_ON_SETATTR | 992 PNFS_LAYOUTRET_ON_ERROR | 993 PNFS_READ_WHOLE_PAGE, 994 .read_pagelist = bl_read_pagelist, 995 .write_pagelist = bl_write_pagelist, 996 .alloc_layout_hdr = sl_alloc_layout_hdr, 997 .free_layout_hdr = bl_free_layout_hdr, 998 .alloc_lseg = bl_alloc_lseg, 999 .free_lseg = bl_free_lseg, 1000 .return_range = bl_return_range, 1001 .prepare_layoutcommit = bl_prepare_layoutcommit, 1002 .cleanup_layoutcommit = bl_cleanup_layoutcommit, 1003 .set_layoutdriver = bl_set_layoutdriver, 1004 .alloc_deviceid_node = bl_alloc_deviceid_node, 1005 .free_deviceid_node = bl_free_deviceid_node, 1006 .pg_read_ops = &bl_pg_read_ops, 1007 .pg_write_ops = &bl_pg_write_ops, 1008 .sync = pnfs_generic_sync, 1009 }; 1010 1011 1012 static int __init nfs4blocklayout_init(void) 1013 { 1014 int ret; 1015 1016 dprintk("%s: NFSv4 Block Layout Driver Registering...\n", __func__); 1017 1018 ret = bl_init_pipefs(); 1019 if (ret) 1020 goto out; 1021 1022 ret = pnfs_register_layoutdriver(&blocklayout_type); 1023 if (ret) 1024 goto out_cleanup_pipe; 1025 1026 ret = pnfs_register_layoutdriver(&scsilayout_type); 1027 if (ret) 1028 goto out_unregister_block; 1029 return 0; 1030 1031 out_unregister_block: 1032 pnfs_unregister_layoutdriver(&blocklayout_type); 1033 out_cleanup_pipe: 1034 bl_cleanup_pipefs(); 1035 out: 1036 return ret; 1037 } 1038 1039 static void __exit nfs4blocklayout_exit(void) 1040 { 1041 dprintk("%s: NFSv4 Block Layout Driver Unregistering...\n", 1042 __func__); 1043 1044 pnfs_unregister_layoutdriver(&scsilayout_type); 1045 pnfs_unregister_layoutdriver(&blocklayout_type); 1046 bl_cleanup_pipefs(); 1047 } 1048 1049 MODULE_ALIAS("nfs-layouttype4-3"); 1050 MODULE_ALIAS("nfs-layouttype4-5"); 1051 1052 module_init(nfs4blocklayout_init); 1053 module_exit(nfs4blocklayout_exit); 1054