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