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 int err = -ENODEV;
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)) {
575 unsigned long end = jiffies;
576 unsigned long start = end - PNFS_DEVICE_RETRY_TIMEOUT;
577
578 if (!time_in_range(node->timestamp_unavailable, start, end)) {
579 nfs4_delete_deviceid(node->ld, node->nfs_client, id);
580 goto retry;
581 }
582 goto out_put;
583 }
584
585 if (!bl_register_dev(container_of(node, struct pnfs_block_dev, node)))
586 goto out_put;
587
588 return node;
589
590 out_put:
591 nfs4_put_deviceid_node(node);
592 return ERR_PTR(err);
593 }
594
595 static int
596 bl_alloc_extent(struct xdr_stream *xdr, struct pnfs_layout_hdr *lo,
597 struct layout_verification *lv, struct list_head *extents,
598 gfp_t gfp_mask)
599 {
600 struct pnfs_block_extent *be;
601 struct nfs4_deviceid id;
602 int error;
603 __be32 *p;
604
605 p = xdr_inline_decode(xdr, 28 + NFS4_DEVICEID4_SIZE);
606 if (!p)
607 return -EIO;
608
609 be = kzalloc(sizeof(*be), GFP_NOFS);
610 if (!be)
611 return -ENOMEM;
612
613 memcpy(&id, p, NFS4_DEVICEID4_SIZE);
614 p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
615
616 be->be_device = bl_find_get_deviceid(NFS_SERVER(lo->plh_inode), &id,
617 lo->plh_lc_cred, gfp_mask);
618 if (IS_ERR(be->be_device)) {
619 error = PTR_ERR(be->be_device);
620 goto out_free_be;
621 }
622
623 /*
624 * The next three values are read in as bytes, but stored in the
625 * extent structure in 512-byte granularity.
626 */
627 error = -EIO;
628 if (decode_sector_number(&p, &be->be_f_offset) < 0)
629 goto out_put_deviceid;
630 if (decode_sector_number(&p, &be->be_length) < 0)
631 goto out_put_deviceid;
632 if (decode_sector_number(&p, &be->be_v_offset) < 0)
633 goto out_put_deviceid;
634 be->be_state = be32_to_cpup(p++);
635
636 error = verify_extent(be, lv);
637 if (error) {
638 dprintk("%s: extent verification failed\n", __func__);
639 goto out_put_deviceid;
640 }
641
642 list_add_tail(&be->be_list, extents);
643 return 0;
644
645 out_put_deviceid:
646 nfs4_put_deviceid_node(be->be_device);
647 out_free_be:
648 kfree(be);
649 return error;
650 }
651
652 static struct pnfs_layout_segment *
653 bl_alloc_lseg(struct pnfs_layout_hdr *lo, struct nfs4_layoutget_res *lgr,
654 gfp_t gfp_mask)
655 {
656 struct layout_verification lv = {
657 .mode = lgr->range.iomode,
658 .start = lgr->range.offset >> SECTOR_SHIFT,
659 .inval = lgr->range.offset >> SECTOR_SHIFT,
660 .cowread = lgr->range.offset >> SECTOR_SHIFT,
661 };
662 struct pnfs_block_layout *bl = BLK_LO2EXT(lo);
663 struct pnfs_layout_segment *lseg;
664 struct xdr_buf buf;
665 struct xdr_stream xdr;
666 struct page *scratch;
667 int status, i;
668 uint32_t count;
669 __be32 *p;
670 LIST_HEAD(extents);
671
672 dprintk("---> %s\n", __func__);
673
674 lseg = kzalloc(sizeof(*lseg), gfp_mask);
675 if (!lseg)
676 return ERR_PTR(-ENOMEM);
677
678 status = -ENOMEM;
679 scratch = alloc_page(gfp_mask);
680 if (!scratch)
681 goto out;
682
683 xdr_init_decode_pages(&xdr, &buf,
684 lgr->layoutp->pages, lgr->layoutp->len);
685 xdr_set_scratch_page(&xdr, scratch);
686
687 status = -EIO;
688 p = xdr_inline_decode(&xdr, 4);
689 if (unlikely(!p))
690 goto out_free_scratch;
691
692 count = be32_to_cpup(p++);
693 dprintk("%s: number of extents %d\n", __func__, count);
694
695 /*
696 * Decode individual extents, putting them in temporary staging area
697 * until whole layout is decoded to make error recovery easier.
698 */
699 for (i = 0; i < count; i++) {
700 status = bl_alloc_extent(&xdr, lo, &lv, &extents, gfp_mask);
701 if (status)
702 goto process_extents;
703 }
704
705 if (lgr->range.offset + lgr->range.length !=
706 lv.start << SECTOR_SHIFT) {
707 dprintk("%s Final length mismatch\n", __func__);
708 status = -EIO;
709 goto process_extents;
710 }
711
712 if (lv.start < lv.cowread) {
713 dprintk("%s Final uncovered COW extent\n", __func__);
714 status = -EIO;
715 }
716
717 process_extents:
718 while (!list_empty(&extents)) {
719 struct pnfs_block_extent *be =
720 list_first_entry(&extents, struct pnfs_block_extent,
721 be_list);
722 list_del(&be->be_list);
723
724 if (!status)
725 status = ext_tree_insert(bl, be);
726
727 if (status) {
728 nfs4_put_deviceid_node(be->be_device);
729 kfree(be);
730 }
731 }
732
733 out_free_scratch:
734 __free_page(scratch);
735 out:
736 dprintk("%s returns %d\n", __func__, status);
737 switch (status) {
738 case -ENODEV:
739 /* Our extent block devices are unavailable */
740 set_bit(NFS_LSEG_UNAVAILABLE, &lseg->pls_flags);
741 fallthrough;
742 case 0:
743 return lseg;
744 default:
745 kfree(lseg);
746 return ERR_PTR(status);
747 }
748 }
749
750 static void
751 bl_return_range(struct pnfs_layout_hdr *lo,
752 struct pnfs_layout_range *range)
753 {
754 struct pnfs_block_layout *bl = BLK_LO2EXT(lo);
755 sector_t offset = range->offset >> SECTOR_SHIFT, end;
756
757 if (range->offset % 8) {
758 dprintk("%s: offset %lld not block size aligned\n",
759 __func__, range->offset);
760 return;
761 }
762
763 if (range->length != NFS4_MAX_UINT64) {
764 if (range->length % 8) {
765 dprintk("%s: length %lld not block size aligned\n",
766 __func__, range->length);
767 return;
768 }
769
770 end = offset + (range->length >> SECTOR_SHIFT);
771 } else {
772 end = round_down(NFS4_MAX_UINT64, PAGE_SIZE);
773 }
774
775 ext_tree_remove(bl, range->iomode & IOMODE_RW, offset, end);
776 }
777
778 static int
779 bl_prepare_layoutcommit(struct nfs4_layoutcommit_args *arg)
780 {
781 return ext_tree_prepare_commit(arg);
782 }
783
784 static void
785 bl_cleanup_layoutcommit(struct nfs4_layoutcommit_data *lcdata)
786 {
787 ext_tree_mark_committed(&lcdata->args, lcdata->res.status);
788 }
789
790 static int
791 bl_set_layoutdriver(struct nfs_server *server, const struct nfs_fh *fh)
792 {
793 dprintk("%s enter\n", __func__);
794
795 if (server->pnfs_blksize == 0) {
796 dprintk("%s Server did not return blksize\n", __func__);
797 return -EINVAL;
798 }
799 if (server->pnfs_blksize > PAGE_SIZE) {
800 printk(KERN_ERR "%s: pNFS blksize %d not supported.\n",
801 __func__, server->pnfs_blksize);
802 return -EINVAL;
803 }
804
805 return 0;
806 }
807
808 static bool
809 is_aligned_req(struct nfs_pageio_descriptor *pgio,
810 struct nfs_page *req, unsigned int alignment, bool is_write)
811 {
812 /*
813 * Always accept buffered writes, higher layers take care of the
814 * right alignment.
815 */
816 if (pgio->pg_dreq == NULL)
817 return true;
818
819 if (!IS_ALIGNED(req->wb_offset, alignment))
820 return false;
821
822 if (IS_ALIGNED(req->wb_bytes, alignment))
823 return true;
824
825 if (is_write &&
826 (req_offset(req) + req->wb_bytes == i_size_read(pgio->pg_inode))) {
827 /*
828 * If the write goes up to the inode size, just write
829 * the full page. Data past the inode size is
830 * guaranteed to be zeroed by the higher level client
831 * code, and this behaviour is mandated by RFC 5663
832 * section 2.3.2.
833 */
834 return true;
835 }
836
837 return false;
838 }
839
840 static void
841 bl_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
842 {
843 if (!is_aligned_req(pgio, req, SECTOR_SIZE, false)) {
844 nfs_pageio_reset_read_mds(pgio);
845 return;
846 }
847
848 pnfs_generic_pg_init_read(pgio, req);
849
850 if (pgio->pg_lseg &&
851 test_bit(NFS_LSEG_UNAVAILABLE, &pgio->pg_lseg->pls_flags)) {
852 pnfs_error_mark_layout_for_return(pgio->pg_inode, pgio->pg_lseg);
853 pnfs_set_lo_fail(pgio->pg_lseg);
854 nfs_pageio_reset_read_mds(pgio);
855 }
856 }
857
858 /*
859 * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
860 * of bytes (maximum @req->wb_bytes) that can be coalesced.
861 */
862 static size_t
863 bl_pg_test_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
864 struct nfs_page *req)
865 {
866 if (!is_aligned_req(pgio, req, SECTOR_SIZE, false))
867 return 0;
868 return pnfs_generic_pg_test(pgio, prev, req);
869 }
870
871 /*
872 * Return the number of contiguous bytes for a given inode
873 * starting at page frame idx.
874 */
875 static u64 pnfs_num_cont_bytes(struct inode *inode, pgoff_t idx)
876 {
877 struct address_space *mapping = inode->i_mapping;
878 pgoff_t end;
879
880 /* Optimize common case that writes from 0 to end of file */
881 end = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE);
882 if (end != inode->i_mapping->nrpages) {
883 rcu_read_lock();
884 end = page_cache_next_miss(mapping, idx + 1, ULONG_MAX);
885 rcu_read_unlock();
886 }
887
888 if (!end)
889 return i_size_read(inode) - (idx << PAGE_SHIFT);
890 else
891 return (end - idx) << PAGE_SHIFT;
892 }
893
894 static void
895 bl_pg_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
896 {
897 u64 wb_size;
898
899 if (!is_aligned_req(pgio, req, PAGE_SIZE, true)) {
900 nfs_pageio_reset_write_mds(pgio);
901 return;
902 }
903
904 if (pgio->pg_dreq == NULL)
905 wb_size = pnfs_num_cont_bytes(pgio->pg_inode, req->wb_index);
906 else
907 wb_size = nfs_dreq_bytes_left(pgio->pg_dreq, req_offset(req));
908
909 pnfs_generic_pg_init_write(pgio, req, wb_size);
910
911 if (pgio->pg_lseg &&
912 test_bit(NFS_LSEG_UNAVAILABLE, &pgio->pg_lseg->pls_flags)) {
913
914 pnfs_error_mark_layout_for_return(pgio->pg_inode, pgio->pg_lseg);
915 pnfs_set_lo_fail(pgio->pg_lseg);
916 nfs_pageio_reset_write_mds(pgio);
917 }
918 }
919
920 /*
921 * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
922 * of bytes (maximum @req->wb_bytes) that can be coalesced.
923 */
924 static size_t
925 bl_pg_test_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
926 struct nfs_page *req)
927 {
928 if (!is_aligned_req(pgio, req, PAGE_SIZE, true))
929 return 0;
930 return pnfs_generic_pg_test(pgio, prev, req);
931 }
932
933 static const struct nfs_pageio_ops bl_pg_read_ops = {
934 .pg_init = bl_pg_init_read,
935 .pg_test = bl_pg_test_read,
936 .pg_doio = pnfs_generic_pg_readpages,
937 .pg_cleanup = pnfs_generic_pg_cleanup,
938 };
939
940 static const struct nfs_pageio_ops bl_pg_write_ops = {
941 .pg_init = bl_pg_init_write,
942 .pg_test = bl_pg_test_write,
943 .pg_doio = pnfs_generic_pg_writepages,
944 .pg_cleanup = pnfs_generic_pg_cleanup,
945 };
946
947 static struct pnfs_layoutdriver_type blocklayout_type = {
948 .id = LAYOUT_BLOCK_VOLUME,
949 .name = "LAYOUT_BLOCK_VOLUME",
950 .owner = THIS_MODULE,
951 .flags = PNFS_LAYOUTRET_ON_SETATTR |
952 PNFS_LAYOUTRET_ON_ERROR |
953 PNFS_READ_WHOLE_PAGE,
954 .read_pagelist = bl_read_pagelist,
955 .write_pagelist = bl_write_pagelist,
956 .alloc_layout_hdr = bl_alloc_layout_hdr,
957 .free_layout_hdr = bl_free_layout_hdr,
958 .alloc_lseg = bl_alloc_lseg,
959 .free_lseg = bl_free_lseg,
960 .return_range = bl_return_range,
961 .prepare_layoutcommit = bl_prepare_layoutcommit,
962 .cleanup_layoutcommit = bl_cleanup_layoutcommit,
963 .set_layoutdriver = bl_set_layoutdriver,
964 .alloc_deviceid_node = bl_alloc_deviceid_node,
965 .free_deviceid_node = bl_free_deviceid_node,
966 .pg_read_ops = &bl_pg_read_ops,
967 .pg_write_ops = &bl_pg_write_ops,
968 .sync = pnfs_generic_sync,
969 };
970
971 static struct pnfs_layoutdriver_type scsilayout_type = {
972 .id = LAYOUT_SCSI,
973 .name = "LAYOUT_SCSI",
974 .owner = THIS_MODULE,
975 .flags = PNFS_LAYOUTRET_ON_SETATTR |
976 PNFS_LAYOUTRET_ON_ERROR |
977 PNFS_READ_WHOLE_PAGE,
978 .read_pagelist = bl_read_pagelist,
979 .write_pagelist = bl_write_pagelist,
980 .alloc_layout_hdr = sl_alloc_layout_hdr,
981 .free_layout_hdr = bl_free_layout_hdr,
982 .alloc_lseg = bl_alloc_lseg,
983 .free_lseg = bl_free_lseg,
984 .return_range = bl_return_range,
985 .prepare_layoutcommit = bl_prepare_layoutcommit,
986 .cleanup_layoutcommit = bl_cleanup_layoutcommit,
987 .set_layoutdriver = bl_set_layoutdriver,
988 .alloc_deviceid_node = bl_alloc_deviceid_node,
989 .free_deviceid_node = bl_free_deviceid_node,
990 .pg_read_ops = &bl_pg_read_ops,
991 .pg_write_ops = &bl_pg_write_ops,
992 .sync = pnfs_generic_sync,
993 };
994
995
996 static int __init nfs4blocklayout_init(void)
997 {
998 int ret;
999
1000 dprintk("%s: NFSv4 Block Layout Driver Registering...\n", __func__);
1001
1002 ret = bl_init_pipefs();
1003 if (ret)
1004 goto out;
1005
1006 ret = pnfs_register_layoutdriver(&blocklayout_type);
1007 if (ret)
1008 goto out_cleanup_pipe;
1009
1010 ret = pnfs_register_layoutdriver(&scsilayout_type);
1011 if (ret)
1012 goto out_unregister_block;
1013 return 0;
1014
1015 out_unregister_block:
1016 pnfs_unregister_layoutdriver(&blocklayout_type);
1017 out_cleanup_pipe:
1018 bl_cleanup_pipefs();
1019 out:
1020 return ret;
1021 }
1022
1023 static void __exit nfs4blocklayout_exit(void)
1024 {
1025 dprintk("%s: NFSv4 Block Layout Driver Unregistering...\n",
1026 __func__);
1027
1028 pnfs_unregister_layoutdriver(&scsilayout_type);
1029 pnfs_unregister_layoutdriver(&blocklayout_type);
1030 bl_cleanup_pipefs();
1031 }
1032
1033 MODULE_ALIAS("nfs-layouttype4-3");
1034 MODULE_ALIAS("nfs-layouttype4-5");
1035
1036 module_init(nfs4blocklayout_init);
1037 module_exit(nfs4blocklayout_exit);
1038
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