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48debafe MP |
1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* | |
3 | * Copyright (C) 2018 Red Hat. All rights reserved. | |
4 | * | |
5 | * This file is released under the GPL. | |
6 | */ | |
7 | ||
8 | #include <linux/device-mapper.h> | |
9 | #include <linux/module.h> | |
10 | #include <linux/init.h> | |
11 | #include <linux/vmalloc.h> | |
12 | #include <linux/kthread.h> | |
13 | #include <linux/dm-io.h> | |
14 | #include <linux/dm-kcopyd.h> | |
15 | #include <linux/dax.h> | |
16 | #include <linux/pfn_t.h> | |
17 | #include <linux/libnvdimm.h> | |
18 | ||
19 | #define DM_MSG_PREFIX "writecache" | |
20 | ||
21 | #define HIGH_WATERMARK 50 | |
22 | #define LOW_WATERMARK 45 | |
23 | #define MAX_WRITEBACK_JOBS 0 | |
24 | #define ENDIO_LATENCY 16 | |
25 | #define WRITEBACK_LATENCY 64 | |
26 | #define AUTOCOMMIT_BLOCKS_SSD 65536 | |
27 | #define AUTOCOMMIT_BLOCKS_PMEM 64 | |
28 | #define AUTOCOMMIT_MSEC 1000 | |
29 | ||
30 | #define BITMAP_GRANULARITY 65536 | |
31 | #if BITMAP_GRANULARITY < PAGE_SIZE | |
32 | #undef BITMAP_GRANULARITY | |
33 | #define BITMAP_GRANULARITY PAGE_SIZE | |
34 | #endif | |
35 | ||
36 | #if IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API) && IS_ENABLED(CONFIG_DAX_DRIVER) | |
37 | #define DM_WRITECACHE_HAS_PMEM | |
38 | #endif | |
39 | ||
40 | #ifdef DM_WRITECACHE_HAS_PMEM | |
41 | #define pmem_assign(dest, src) \ | |
42 | do { \ | |
43 | typeof(dest) uniq = (src); \ | |
44 | memcpy_flushcache(&(dest), &uniq, sizeof(dest)); \ | |
45 | } while (0) | |
46 | #else | |
47 | #define pmem_assign(dest, src) ((dest) = (src)) | |
48 | #endif | |
49 | ||
50 | #if defined(__HAVE_ARCH_MEMCPY_MCSAFE) && defined(DM_WRITECACHE_HAS_PMEM) | |
51 | #define DM_WRITECACHE_HANDLE_HARDWARE_ERRORS | |
52 | #endif | |
53 | ||
54 | #define MEMORY_SUPERBLOCK_MAGIC 0x23489321 | |
55 | #define MEMORY_SUPERBLOCK_VERSION 1 | |
56 | ||
57 | struct wc_memory_entry { | |
58 | __le64 original_sector; | |
59 | __le64 seq_count; | |
60 | }; | |
61 | ||
62 | struct wc_memory_superblock { | |
63 | union { | |
64 | struct { | |
65 | __le32 magic; | |
66 | __le32 version; | |
67 | __le32 block_size; | |
68 | __le32 pad; | |
69 | __le64 n_blocks; | |
70 | __le64 seq_count; | |
71 | }; | |
72 | __le64 padding[8]; | |
73 | }; | |
74 | struct wc_memory_entry entries[0]; | |
75 | }; | |
76 | ||
77 | struct wc_entry { | |
78 | struct rb_node rb_node; | |
79 | struct list_head lru; | |
80 | unsigned short wc_list_contiguous; | |
81 | bool write_in_progress | |
82 | #if BITS_PER_LONG == 64 | |
83 | :1 | |
84 | #endif | |
85 | ; | |
86 | unsigned long index | |
87 | #if BITS_PER_LONG == 64 | |
88 | :47 | |
89 | #endif | |
90 | ; | |
91 | #ifdef DM_WRITECACHE_HANDLE_HARDWARE_ERRORS | |
92 | uint64_t original_sector; | |
93 | uint64_t seq_count; | |
94 | #endif | |
95 | }; | |
96 | ||
97 | #ifdef DM_WRITECACHE_HAS_PMEM | |
98 | #define WC_MODE_PMEM(wc) ((wc)->pmem_mode) | |
99 | #define WC_MODE_FUA(wc) ((wc)->writeback_fua) | |
100 | #else | |
101 | #define WC_MODE_PMEM(wc) false | |
102 | #define WC_MODE_FUA(wc) false | |
103 | #endif | |
104 | #define WC_MODE_SORT_FREELIST(wc) (!WC_MODE_PMEM(wc)) | |
105 | ||
106 | struct dm_writecache { | |
107 | struct mutex lock; | |
108 | struct list_head lru; | |
109 | union { | |
110 | struct list_head freelist; | |
111 | struct { | |
112 | struct rb_root freetree; | |
113 | struct wc_entry *current_free; | |
114 | }; | |
115 | }; | |
116 | struct rb_root tree; | |
117 | ||
118 | size_t freelist_size; | |
119 | size_t writeback_size; | |
120 | size_t freelist_high_watermark; | |
121 | size_t freelist_low_watermark; | |
122 | ||
123 | unsigned uncommitted_blocks; | |
124 | unsigned autocommit_blocks; | |
125 | unsigned max_writeback_jobs; | |
126 | ||
127 | int error; | |
128 | ||
129 | unsigned long autocommit_jiffies; | |
130 | struct timer_list autocommit_timer; | |
131 | struct wait_queue_head freelist_wait; | |
132 | ||
133 | atomic_t bio_in_progress[2]; | |
134 | struct wait_queue_head bio_in_progress_wait[2]; | |
135 | ||
136 | struct dm_target *ti; | |
137 | struct dm_dev *dev; | |
138 | struct dm_dev *ssd_dev; | |
d284f824 | 139 | sector_t start_sector; |
48debafe MP |
140 | void *memory_map; |
141 | uint64_t memory_map_size; | |
142 | size_t metadata_sectors; | |
143 | size_t n_blocks; | |
144 | uint64_t seq_count; | |
145 | void *block_start; | |
146 | struct wc_entry *entries; | |
147 | unsigned block_size; | |
148 | unsigned char block_size_bits; | |
149 | ||
150 | bool pmem_mode:1; | |
151 | bool writeback_fua:1; | |
152 | ||
153 | bool overwrote_committed:1; | |
154 | bool memory_vmapped:1; | |
155 | ||
156 | bool high_wm_percent_set:1; | |
157 | bool low_wm_percent_set:1; | |
158 | bool max_writeback_jobs_set:1; | |
159 | bool autocommit_blocks_set:1; | |
160 | bool autocommit_time_set:1; | |
161 | bool writeback_fua_set:1; | |
162 | bool flush_on_suspend:1; | |
163 | ||
164 | unsigned writeback_all; | |
165 | struct workqueue_struct *writeback_wq; | |
166 | struct work_struct writeback_work; | |
167 | struct work_struct flush_work; | |
168 | ||
169 | struct dm_io_client *dm_io; | |
170 | ||
171 | raw_spinlock_t endio_list_lock; | |
172 | struct list_head endio_list; | |
173 | struct task_struct *endio_thread; | |
174 | ||
175 | struct task_struct *flush_thread; | |
176 | struct bio_list flush_list; | |
177 | ||
178 | struct dm_kcopyd_client *dm_kcopyd; | |
179 | unsigned long *dirty_bitmap; | |
180 | unsigned dirty_bitmap_size; | |
181 | ||
182 | struct bio_set bio_set; | |
183 | mempool_t copy_pool; | |
184 | }; | |
185 | ||
186 | #define WB_LIST_INLINE 16 | |
187 | ||
188 | struct writeback_struct { | |
189 | struct list_head endio_entry; | |
190 | struct dm_writecache *wc; | |
191 | struct wc_entry **wc_list; | |
192 | unsigned wc_list_n; | |
193 | unsigned page_offset; | |
194 | struct page *page; | |
195 | struct wc_entry *wc_list_inline[WB_LIST_INLINE]; | |
196 | struct bio bio; | |
197 | }; | |
198 | ||
199 | struct copy_struct { | |
200 | struct list_head endio_entry; | |
201 | struct dm_writecache *wc; | |
202 | struct wc_entry *e; | |
203 | unsigned n_entries; | |
204 | int error; | |
205 | }; | |
206 | ||
207 | DECLARE_DM_KCOPYD_THROTTLE_WITH_MODULE_PARM(dm_writecache_throttle, | |
208 | "A percentage of time allocated for data copying"); | |
209 | ||
210 | static void wc_lock(struct dm_writecache *wc) | |
211 | { | |
212 | mutex_lock(&wc->lock); | |
213 | } | |
214 | ||
215 | static void wc_unlock(struct dm_writecache *wc) | |
216 | { | |
217 | mutex_unlock(&wc->lock); | |
218 | } | |
219 | ||
220 | #ifdef DM_WRITECACHE_HAS_PMEM | |
221 | static int persistent_memory_claim(struct dm_writecache *wc) | |
222 | { | |
223 | int r; | |
224 | loff_t s; | |
225 | long p, da; | |
226 | pfn_t pfn; | |
227 | int id; | |
228 | struct page **pages; | |
229 | ||
230 | wc->memory_vmapped = false; | |
231 | ||
232 | if (!wc->ssd_dev->dax_dev) { | |
233 | r = -EOPNOTSUPP; | |
234 | goto err1; | |
235 | } | |
236 | s = wc->memory_map_size; | |
237 | p = s >> PAGE_SHIFT; | |
238 | if (!p) { | |
239 | r = -EINVAL; | |
240 | goto err1; | |
241 | } | |
242 | if (p != s >> PAGE_SHIFT) { | |
243 | r = -EOVERFLOW; | |
244 | goto err1; | |
245 | } | |
246 | ||
247 | id = dax_read_lock(); | |
248 | ||
249 | da = dax_direct_access(wc->ssd_dev->dax_dev, 0, p, &wc->memory_map, &pfn); | |
250 | if (da < 0) { | |
251 | wc->memory_map = NULL; | |
252 | r = da; | |
253 | goto err2; | |
254 | } | |
255 | if (!pfn_t_has_page(pfn)) { | |
256 | wc->memory_map = NULL; | |
257 | r = -EOPNOTSUPP; | |
258 | goto err2; | |
259 | } | |
260 | if (da != p) { | |
261 | long i; | |
262 | wc->memory_map = NULL; | |
50a7d3ba | 263 | pages = kvmalloc_array(p, sizeof(struct page *), GFP_KERNEL); |
48debafe MP |
264 | if (!pages) { |
265 | r = -ENOMEM; | |
266 | goto err2; | |
267 | } | |
268 | i = 0; | |
269 | do { | |
270 | long daa; | |
48debafe | 271 | daa = dax_direct_access(wc->ssd_dev->dax_dev, i, p - i, |
f742267a | 272 | NULL, &pfn); |
48debafe MP |
273 | if (daa <= 0) { |
274 | r = daa ? daa : -EINVAL; | |
275 | goto err3; | |
276 | } | |
277 | if (!pfn_t_has_page(pfn)) { | |
278 | r = -EOPNOTSUPP; | |
279 | goto err3; | |
280 | } | |
281 | while (daa-- && i < p) { | |
282 | pages[i++] = pfn_t_to_page(pfn); | |
283 | pfn.val++; | |
284 | } | |
285 | } while (i < p); | |
286 | wc->memory_map = vmap(pages, p, VM_MAP, PAGE_KERNEL); | |
287 | if (!wc->memory_map) { | |
288 | r = -ENOMEM; | |
289 | goto err3; | |
290 | } | |
291 | kvfree(pages); | |
292 | wc->memory_vmapped = true; | |
293 | } | |
294 | ||
295 | dax_read_unlock(id); | |
d284f824 MP |
296 | |
297 | wc->memory_map += (size_t)wc->start_sector << SECTOR_SHIFT; | |
298 | wc->memory_map_size -= (size_t)wc->start_sector << SECTOR_SHIFT; | |
299 | ||
48debafe MP |
300 | return 0; |
301 | err3: | |
302 | kvfree(pages); | |
303 | err2: | |
304 | dax_read_unlock(id); | |
305 | err1: | |
306 | return r; | |
307 | } | |
308 | #else | |
309 | static int persistent_memory_claim(struct dm_writecache *wc) | |
310 | { | |
311 | BUG(); | |
312 | } | |
313 | #endif | |
314 | ||
315 | static void persistent_memory_release(struct dm_writecache *wc) | |
316 | { | |
317 | if (wc->memory_vmapped) | |
d284f824 | 318 | vunmap(wc->memory_map - ((size_t)wc->start_sector << SECTOR_SHIFT)); |
48debafe MP |
319 | } |
320 | ||
321 | static struct page *persistent_memory_page(void *addr) | |
322 | { | |
323 | if (is_vmalloc_addr(addr)) | |
324 | return vmalloc_to_page(addr); | |
325 | else | |
326 | return virt_to_page(addr); | |
327 | } | |
328 | ||
329 | static unsigned persistent_memory_page_offset(void *addr) | |
330 | { | |
331 | return (unsigned long)addr & (PAGE_SIZE - 1); | |
332 | } | |
333 | ||
334 | static void persistent_memory_flush_cache(void *ptr, size_t size) | |
335 | { | |
336 | if (is_vmalloc_addr(ptr)) | |
337 | flush_kernel_vmap_range(ptr, size); | |
338 | } | |
339 | ||
340 | static void persistent_memory_invalidate_cache(void *ptr, size_t size) | |
341 | { | |
342 | if (is_vmalloc_addr(ptr)) | |
343 | invalidate_kernel_vmap_range(ptr, size); | |
344 | } | |
345 | ||
346 | static struct wc_memory_superblock *sb(struct dm_writecache *wc) | |
347 | { | |
348 | return wc->memory_map; | |
349 | } | |
350 | ||
351 | static struct wc_memory_entry *memory_entry(struct dm_writecache *wc, struct wc_entry *e) | |
352 | { | |
353 | if (is_power_of_2(sizeof(struct wc_entry)) && 0) | |
354 | return &sb(wc)->entries[e - wc->entries]; | |
355 | else | |
356 | return &sb(wc)->entries[e->index]; | |
357 | } | |
358 | ||
359 | static void *memory_data(struct dm_writecache *wc, struct wc_entry *e) | |
360 | { | |
361 | return (char *)wc->block_start + (e->index << wc->block_size_bits); | |
362 | } | |
363 | ||
364 | static sector_t cache_sector(struct dm_writecache *wc, struct wc_entry *e) | |
365 | { | |
d284f824 | 366 | return wc->start_sector + wc->metadata_sectors + |
48debafe MP |
367 | ((sector_t)e->index << (wc->block_size_bits - SECTOR_SHIFT)); |
368 | } | |
369 | ||
370 | static uint64_t read_original_sector(struct dm_writecache *wc, struct wc_entry *e) | |
371 | { | |
372 | #ifdef DM_WRITECACHE_HANDLE_HARDWARE_ERRORS | |
373 | return e->original_sector; | |
374 | #else | |
375 | return le64_to_cpu(memory_entry(wc, e)->original_sector); | |
376 | #endif | |
377 | } | |
378 | ||
379 | static uint64_t read_seq_count(struct dm_writecache *wc, struct wc_entry *e) | |
380 | { | |
381 | #ifdef DM_WRITECACHE_HANDLE_HARDWARE_ERRORS | |
382 | return e->seq_count; | |
383 | #else | |
384 | return le64_to_cpu(memory_entry(wc, e)->seq_count); | |
385 | #endif | |
386 | } | |
387 | ||
388 | static void clear_seq_count(struct dm_writecache *wc, struct wc_entry *e) | |
389 | { | |
390 | #ifdef DM_WRITECACHE_HANDLE_HARDWARE_ERRORS | |
391 | e->seq_count = -1; | |
392 | #endif | |
393 | pmem_assign(memory_entry(wc, e)->seq_count, cpu_to_le64(-1)); | |
394 | } | |
395 | ||
396 | static void write_original_sector_seq_count(struct dm_writecache *wc, struct wc_entry *e, | |
397 | uint64_t original_sector, uint64_t seq_count) | |
398 | { | |
399 | struct wc_memory_entry me; | |
400 | #ifdef DM_WRITECACHE_HANDLE_HARDWARE_ERRORS | |
401 | e->original_sector = original_sector; | |
402 | e->seq_count = seq_count; | |
403 | #endif | |
404 | me.original_sector = cpu_to_le64(original_sector); | |
405 | me.seq_count = cpu_to_le64(seq_count); | |
406 | pmem_assign(*memory_entry(wc, e), me); | |
407 | } | |
408 | ||
409 | #define writecache_error(wc, err, msg, arg...) \ | |
410 | do { \ | |
411 | if (!cmpxchg(&(wc)->error, 0, err)) \ | |
412 | DMERR(msg, ##arg); \ | |
413 | wake_up(&(wc)->freelist_wait); \ | |
414 | } while (0) | |
415 | ||
416 | #define writecache_has_error(wc) (unlikely(READ_ONCE((wc)->error))) | |
417 | ||
418 | static void writecache_flush_all_metadata(struct dm_writecache *wc) | |
419 | { | |
420 | if (!WC_MODE_PMEM(wc)) | |
421 | memset(wc->dirty_bitmap, -1, wc->dirty_bitmap_size); | |
422 | } | |
423 | ||
424 | static void writecache_flush_region(struct dm_writecache *wc, void *ptr, size_t size) | |
425 | { | |
426 | if (!WC_MODE_PMEM(wc)) | |
427 | __set_bit(((char *)ptr - (char *)wc->memory_map) / BITMAP_GRANULARITY, | |
428 | wc->dirty_bitmap); | |
429 | } | |
430 | ||
431 | static void writecache_disk_flush(struct dm_writecache *wc, struct dm_dev *dev); | |
432 | ||
433 | struct io_notify { | |
434 | struct dm_writecache *wc; | |
435 | struct completion c; | |
436 | atomic_t count; | |
437 | }; | |
438 | ||
439 | static void writecache_notify_io(unsigned long error, void *context) | |
440 | { | |
441 | struct io_notify *endio = context; | |
442 | ||
443 | if (unlikely(error != 0)) | |
444 | writecache_error(endio->wc, -EIO, "error writing metadata"); | |
445 | BUG_ON(atomic_read(&endio->count) <= 0); | |
446 | if (atomic_dec_and_test(&endio->count)) | |
447 | complete(&endio->c); | |
448 | } | |
449 | ||
450 | static void ssd_commit_flushed(struct dm_writecache *wc) | |
451 | { | |
452 | struct dm_io_region region; | |
453 | struct dm_io_request req; | |
454 | struct io_notify endio = { | |
455 | wc, | |
456 | COMPLETION_INITIALIZER_ONSTACK(endio.c), | |
457 | ATOMIC_INIT(1), | |
458 | }; | |
1e1132ea | 459 | unsigned bitmap_bits = wc->dirty_bitmap_size * 8; |
48debafe MP |
460 | unsigned i = 0; |
461 | ||
462 | while (1) { | |
463 | unsigned j; | |
464 | i = find_next_bit(wc->dirty_bitmap, bitmap_bits, i); | |
465 | if (unlikely(i == bitmap_bits)) | |
466 | break; | |
467 | j = find_next_zero_bit(wc->dirty_bitmap, bitmap_bits, i); | |
468 | ||
469 | region.bdev = wc->ssd_dev->bdev; | |
470 | region.sector = (sector_t)i * (BITMAP_GRANULARITY >> SECTOR_SHIFT); | |
471 | region.count = (sector_t)(j - i) * (BITMAP_GRANULARITY >> SECTOR_SHIFT); | |
472 | ||
473 | if (unlikely(region.sector >= wc->metadata_sectors)) | |
474 | break; | |
475 | if (unlikely(region.sector + region.count > wc->metadata_sectors)) | |
476 | region.count = wc->metadata_sectors - region.sector; | |
477 | ||
d284f824 | 478 | region.sector += wc->start_sector; |
48debafe MP |
479 | atomic_inc(&endio.count); |
480 | req.bi_op = REQ_OP_WRITE; | |
481 | req.bi_op_flags = REQ_SYNC; | |
482 | req.mem.type = DM_IO_VMA; | |
483 | req.mem.ptr.vma = (char *)wc->memory_map + (size_t)i * BITMAP_GRANULARITY; | |
484 | req.client = wc->dm_io; | |
485 | req.notify.fn = writecache_notify_io; | |
486 | req.notify.context = &endio; | |
487 | ||
488 | /* writing via async dm-io (implied by notify.fn above) won't return an error */ | |
489 | (void) dm_io(&req, 1, ®ion, NULL); | |
490 | i = j; | |
491 | } | |
492 | ||
493 | writecache_notify_io(0, &endio); | |
494 | wait_for_completion_io(&endio.c); | |
495 | ||
496 | writecache_disk_flush(wc, wc->ssd_dev); | |
497 | ||
498 | memset(wc->dirty_bitmap, 0, wc->dirty_bitmap_size); | |
499 | } | |
500 | ||
501 | static void writecache_commit_flushed(struct dm_writecache *wc) | |
502 | { | |
503 | if (WC_MODE_PMEM(wc)) | |
504 | wmb(); | |
505 | else | |
506 | ssd_commit_flushed(wc); | |
507 | } | |
508 | ||
509 | static void writecache_disk_flush(struct dm_writecache *wc, struct dm_dev *dev) | |
510 | { | |
511 | int r; | |
512 | struct dm_io_region region; | |
513 | struct dm_io_request req; | |
514 | ||
515 | region.bdev = dev->bdev; | |
516 | region.sector = 0; | |
517 | region.count = 0; | |
518 | req.bi_op = REQ_OP_WRITE; | |
519 | req.bi_op_flags = REQ_PREFLUSH; | |
520 | req.mem.type = DM_IO_KMEM; | |
521 | req.mem.ptr.addr = NULL; | |
522 | req.client = wc->dm_io; | |
523 | req.notify.fn = NULL; | |
524 | ||
525 | r = dm_io(&req, 1, ®ion, NULL); | |
526 | if (unlikely(r)) | |
527 | writecache_error(wc, r, "error flushing metadata: %d", r); | |
528 | } | |
529 | ||
530 | static void writecache_wait_for_ios(struct dm_writecache *wc, int direction) | |
531 | { | |
532 | wait_event(wc->bio_in_progress_wait[direction], | |
533 | !atomic_read(&wc->bio_in_progress[direction])); | |
534 | } | |
535 | ||
536 | #define WFE_RETURN_FOLLOWING 1 | |
537 | #define WFE_LOWEST_SEQ 2 | |
538 | ||
539 | static struct wc_entry *writecache_find_entry(struct dm_writecache *wc, | |
540 | uint64_t block, int flags) | |
541 | { | |
542 | struct wc_entry *e; | |
543 | struct rb_node *node = wc->tree.rb_node; | |
544 | ||
545 | if (unlikely(!node)) | |
546 | return NULL; | |
547 | ||
548 | while (1) { | |
549 | e = container_of(node, struct wc_entry, rb_node); | |
550 | if (read_original_sector(wc, e) == block) | |
551 | break; | |
552 | node = (read_original_sector(wc, e) >= block ? | |
553 | e->rb_node.rb_left : e->rb_node.rb_right); | |
554 | if (unlikely(!node)) { | |
555 | if (!(flags & WFE_RETURN_FOLLOWING)) { | |
556 | return NULL; | |
557 | } | |
558 | if (read_original_sector(wc, e) >= block) { | |
559 | break; | |
560 | } else { | |
561 | node = rb_next(&e->rb_node); | |
562 | if (unlikely(!node)) { | |
563 | return NULL; | |
564 | } | |
565 | e = container_of(node, struct wc_entry, rb_node); | |
566 | break; | |
567 | } | |
568 | } | |
569 | } | |
570 | ||
571 | while (1) { | |
572 | struct wc_entry *e2; | |
573 | if (flags & WFE_LOWEST_SEQ) | |
574 | node = rb_prev(&e->rb_node); | |
575 | else | |
576 | node = rb_next(&e->rb_node); | |
577 | if (!node) | |
578 | return e; | |
579 | e2 = container_of(node, struct wc_entry, rb_node); | |
580 | if (read_original_sector(wc, e2) != block) | |
581 | return e; | |
582 | e = e2; | |
583 | } | |
584 | } | |
585 | ||
586 | static void writecache_insert_entry(struct dm_writecache *wc, struct wc_entry *ins) | |
587 | { | |
588 | struct wc_entry *e; | |
589 | struct rb_node **node = &wc->tree.rb_node, *parent = NULL; | |
590 | ||
591 | while (*node) { | |
592 | e = container_of(*node, struct wc_entry, rb_node); | |
593 | parent = &e->rb_node; | |
594 | if (read_original_sector(wc, e) > read_original_sector(wc, ins)) | |
595 | node = &parent->rb_left; | |
596 | else | |
597 | node = &parent->rb_right; | |
598 | } | |
599 | rb_link_node(&ins->rb_node, parent, node); | |
600 | rb_insert_color(&ins->rb_node, &wc->tree); | |
601 | list_add(&ins->lru, &wc->lru); | |
602 | } | |
603 | ||
604 | static void writecache_unlink(struct dm_writecache *wc, struct wc_entry *e) | |
605 | { | |
606 | list_del(&e->lru); | |
607 | rb_erase(&e->rb_node, &wc->tree); | |
608 | } | |
609 | ||
610 | static void writecache_add_to_freelist(struct dm_writecache *wc, struct wc_entry *e) | |
611 | { | |
612 | if (WC_MODE_SORT_FREELIST(wc)) { | |
613 | struct rb_node **node = &wc->freetree.rb_node, *parent = NULL; | |
614 | if (unlikely(!*node)) | |
615 | wc->current_free = e; | |
616 | while (*node) { | |
617 | parent = *node; | |
618 | if (&e->rb_node < *node) | |
619 | node = &parent->rb_left; | |
620 | else | |
621 | node = &parent->rb_right; | |
622 | } | |
623 | rb_link_node(&e->rb_node, parent, node); | |
624 | rb_insert_color(&e->rb_node, &wc->freetree); | |
625 | } else { | |
626 | list_add_tail(&e->lru, &wc->freelist); | |
627 | } | |
628 | wc->freelist_size++; | |
629 | } | |
630 | ||
631 | static struct wc_entry *writecache_pop_from_freelist(struct dm_writecache *wc) | |
632 | { | |
633 | struct wc_entry *e; | |
634 | ||
635 | if (WC_MODE_SORT_FREELIST(wc)) { | |
636 | struct rb_node *next; | |
637 | if (unlikely(!wc->current_free)) | |
638 | return NULL; | |
639 | e = wc->current_free; | |
640 | next = rb_next(&e->rb_node); | |
641 | rb_erase(&e->rb_node, &wc->freetree); | |
642 | if (unlikely(!next)) | |
643 | next = rb_first(&wc->freetree); | |
644 | wc->current_free = next ? container_of(next, struct wc_entry, rb_node) : NULL; | |
645 | } else { | |
646 | if (unlikely(list_empty(&wc->freelist))) | |
647 | return NULL; | |
648 | e = container_of(wc->freelist.next, struct wc_entry, lru); | |
649 | list_del(&e->lru); | |
650 | } | |
651 | wc->freelist_size--; | |
652 | if (unlikely(wc->freelist_size + wc->writeback_size <= wc->freelist_high_watermark)) | |
653 | queue_work(wc->writeback_wq, &wc->writeback_work); | |
654 | ||
655 | return e; | |
656 | } | |
657 | ||
658 | static void writecache_free_entry(struct dm_writecache *wc, struct wc_entry *e) | |
659 | { | |
660 | writecache_unlink(wc, e); | |
661 | writecache_add_to_freelist(wc, e); | |
662 | clear_seq_count(wc, e); | |
663 | writecache_flush_region(wc, memory_entry(wc, e), sizeof(struct wc_memory_entry)); | |
664 | if (unlikely(waitqueue_active(&wc->freelist_wait))) | |
665 | wake_up(&wc->freelist_wait); | |
666 | } | |
667 | ||
668 | static void writecache_wait_on_freelist(struct dm_writecache *wc) | |
669 | { | |
670 | DEFINE_WAIT(wait); | |
671 | ||
672 | prepare_to_wait(&wc->freelist_wait, &wait, TASK_UNINTERRUPTIBLE); | |
673 | wc_unlock(wc); | |
674 | io_schedule(); | |
675 | finish_wait(&wc->freelist_wait, &wait); | |
676 | wc_lock(wc); | |
677 | } | |
678 | ||
679 | static void writecache_poison_lists(struct dm_writecache *wc) | |
680 | { | |
681 | /* | |
682 | * Catch incorrect access to these values while the device is suspended. | |
683 | */ | |
684 | memset(&wc->tree, -1, sizeof wc->tree); | |
685 | wc->lru.next = LIST_POISON1; | |
686 | wc->lru.prev = LIST_POISON2; | |
687 | wc->freelist.next = LIST_POISON1; | |
688 | wc->freelist.prev = LIST_POISON2; | |
689 | } | |
690 | ||
691 | static void writecache_flush_entry(struct dm_writecache *wc, struct wc_entry *e) | |
692 | { | |
693 | writecache_flush_region(wc, memory_entry(wc, e), sizeof(struct wc_memory_entry)); | |
694 | if (WC_MODE_PMEM(wc)) | |
695 | writecache_flush_region(wc, memory_data(wc, e), wc->block_size); | |
696 | } | |
697 | ||
698 | static bool writecache_entry_is_committed(struct dm_writecache *wc, struct wc_entry *e) | |
699 | { | |
700 | return read_seq_count(wc, e) < wc->seq_count; | |
701 | } | |
702 | ||
703 | static void writecache_flush(struct dm_writecache *wc) | |
704 | { | |
705 | struct wc_entry *e, *e2; | |
706 | bool need_flush_after_free; | |
707 | ||
708 | wc->uncommitted_blocks = 0; | |
709 | del_timer(&wc->autocommit_timer); | |
710 | ||
711 | if (list_empty(&wc->lru)) | |
712 | return; | |
713 | ||
714 | e = container_of(wc->lru.next, struct wc_entry, lru); | |
715 | if (writecache_entry_is_committed(wc, e)) { | |
716 | if (wc->overwrote_committed) { | |
717 | writecache_wait_for_ios(wc, WRITE); | |
718 | writecache_disk_flush(wc, wc->ssd_dev); | |
719 | wc->overwrote_committed = false; | |
720 | } | |
721 | return; | |
722 | } | |
723 | while (1) { | |
724 | writecache_flush_entry(wc, e); | |
725 | if (unlikely(e->lru.next == &wc->lru)) | |
726 | break; | |
727 | e2 = container_of(e->lru.next, struct wc_entry, lru); | |
728 | if (writecache_entry_is_committed(wc, e2)) | |
729 | break; | |
730 | e = e2; | |
731 | cond_resched(); | |
732 | } | |
733 | writecache_commit_flushed(wc); | |
734 | ||
735 | writecache_wait_for_ios(wc, WRITE); | |
736 | ||
737 | wc->seq_count++; | |
738 | pmem_assign(sb(wc)->seq_count, cpu_to_le64(wc->seq_count)); | |
739 | writecache_flush_region(wc, &sb(wc)->seq_count, sizeof sb(wc)->seq_count); | |
740 | writecache_commit_flushed(wc); | |
741 | ||
742 | wc->overwrote_committed = false; | |
743 | ||
744 | need_flush_after_free = false; | |
745 | while (1) { | |
746 | /* Free another committed entry with lower seq-count */ | |
747 | struct rb_node *rb_node = rb_prev(&e->rb_node); | |
748 | ||
749 | if (rb_node) { | |
750 | e2 = container_of(rb_node, struct wc_entry, rb_node); | |
751 | if (read_original_sector(wc, e2) == read_original_sector(wc, e) && | |
752 | likely(!e2->write_in_progress)) { | |
753 | writecache_free_entry(wc, e2); | |
754 | need_flush_after_free = true; | |
755 | } | |
756 | } | |
757 | if (unlikely(e->lru.prev == &wc->lru)) | |
758 | break; | |
759 | e = container_of(e->lru.prev, struct wc_entry, lru); | |
760 | cond_resched(); | |
761 | } | |
762 | ||
763 | if (need_flush_after_free) | |
764 | writecache_commit_flushed(wc); | |
765 | } | |
766 | ||
767 | static void writecache_flush_work(struct work_struct *work) | |
768 | { | |
769 | struct dm_writecache *wc = container_of(work, struct dm_writecache, flush_work); | |
770 | ||
771 | wc_lock(wc); | |
772 | writecache_flush(wc); | |
773 | wc_unlock(wc); | |
774 | } | |
775 | ||
776 | static void writecache_autocommit_timer(struct timer_list *t) | |
777 | { | |
778 | struct dm_writecache *wc = from_timer(wc, t, autocommit_timer); | |
779 | if (!writecache_has_error(wc)) | |
780 | queue_work(wc->writeback_wq, &wc->flush_work); | |
781 | } | |
782 | ||
783 | static void writecache_schedule_autocommit(struct dm_writecache *wc) | |
784 | { | |
785 | if (!timer_pending(&wc->autocommit_timer)) | |
786 | mod_timer(&wc->autocommit_timer, jiffies + wc->autocommit_jiffies); | |
787 | } | |
788 | ||
789 | static void writecache_discard(struct dm_writecache *wc, sector_t start, sector_t end) | |
790 | { | |
791 | struct wc_entry *e; | |
792 | bool discarded_something = false; | |
793 | ||
794 | e = writecache_find_entry(wc, start, WFE_RETURN_FOLLOWING | WFE_LOWEST_SEQ); | |
795 | if (unlikely(!e)) | |
796 | return; | |
797 | ||
798 | while (read_original_sector(wc, e) < end) { | |
799 | struct rb_node *node = rb_next(&e->rb_node); | |
800 | ||
801 | if (likely(!e->write_in_progress)) { | |
802 | if (!discarded_something) { | |
803 | writecache_wait_for_ios(wc, READ); | |
804 | writecache_wait_for_ios(wc, WRITE); | |
805 | discarded_something = true; | |
806 | } | |
807 | writecache_free_entry(wc, e); | |
808 | } | |
809 | ||
810 | if (!node) | |
811 | break; | |
812 | ||
813 | e = container_of(node, struct wc_entry, rb_node); | |
814 | } | |
815 | ||
816 | if (discarded_something) | |
817 | writecache_commit_flushed(wc); | |
818 | } | |
819 | ||
820 | static bool writecache_wait_for_writeback(struct dm_writecache *wc) | |
821 | { | |
822 | if (wc->writeback_size) { | |
823 | writecache_wait_on_freelist(wc); | |
824 | return true; | |
825 | } | |
826 | return false; | |
827 | } | |
828 | ||
829 | static void writecache_suspend(struct dm_target *ti) | |
830 | { | |
831 | struct dm_writecache *wc = ti->private; | |
832 | bool flush_on_suspend; | |
833 | ||
834 | del_timer_sync(&wc->autocommit_timer); | |
835 | ||
836 | wc_lock(wc); | |
837 | writecache_flush(wc); | |
838 | flush_on_suspend = wc->flush_on_suspend; | |
839 | if (flush_on_suspend) { | |
840 | wc->flush_on_suspend = false; | |
841 | wc->writeback_all++; | |
842 | queue_work(wc->writeback_wq, &wc->writeback_work); | |
843 | } | |
844 | wc_unlock(wc); | |
845 | ||
846 | flush_workqueue(wc->writeback_wq); | |
847 | ||
848 | wc_lock(wc); | |
849 | if (flush_on_suspend) | |
850 | wc->writeback_all--; | |
851 | while (writecache_wait_for_writeback(wc)); | |
852 | ||
853 | if (WC_MODE_PMEM(wc)) | |
854 | persistent_memory_flush_cache(wc->memory_map, wc->memory_map_size); | |
855 | ||
856 | writecache_poison_lists(wc); | |
857 | ||
858 | wc_unlock(wc); | |
859 | } | |
860 | ||
861 | static int writecache_alloc_entries(struct dm_writecache *wc) | |
862 | { | |
863 | size_t b; | |
864 | ||
865 | if (wc->entries) | |
866 | return 0; | |
50a7d3ba | 867 | wc->entries = vmalloc(array_size(sizeof(struct wc_entry), wc->n_blocks)); |
48debafe MP |
868 | if (!wc->entries) |
869 | return -ENOMEM; | |
870 | for (b = 0; b < wc->n_blocks; b++) { | |
871 | struct wc_entry *e = &wc->entries[b]; | |
872 | e->index = b; | |
873 | e->write_in_progress = false; | |
874 | } | |
875 | ||
876 | return 0; | |
877 | } | |
878 | ||
879 | static void writecache_resume(struct dm_target *ti) | |
880 | { | |
881 | struct dm_writecache *wc = ti->private; | |
882 | size_t b; | |
883 | bool need_flush = false; | |
884 | __le64 sb_seq_count; | |
885 | int r; | |
886 | ||
887 | wc_lock(wc); | |
888 | ||
889 | if (WC_MODE_PMEM(wc)) | |
890 | persistent_memory_invalidate_cache(wc->memory_map, wc->memory_map_size); | |
891 | ||
892 | wc->tree = RB_ROOT; | |
893 | INIT_LIST_HEAD(&wc->lru); | |
894 | if (WC_MODE_SORT_FREELIST(wc)) { | |
895 | wc->freetree = RB_ROOT; | |
896 | wc->current_free = NULL; | |
897 | } else { | |
898 | INIT_LIST_HEAD(&wc->freelist); | |
899 | } | |
900 | wc->freelist_size = 0; | |
901 | ||
902 | r = memcpy_mcsafe(&sb_seq_count, &sb(wc)->seq_count, sizeof(uint64_t)); | |
903 | if (r) { | |
904 | writecache_error(wc, r, "hardware memory error when reading superblock: %d", r); | |
905 | sb_seq_count = cpu_to_le64(0); | |
906 | } | |
907 | wc->seq_count = le64_to_cpu(sb_seq_count); | |
908 | ||
909 | #ifdef DM_WRITECACHE_HANDLE_HARDWARE_ERRORS | |
910 | for (b = 0; b < wc->n_blocks; b++) { | |
911 | struct wc_entry *e = &wc->entries[b]; | |
912 | struct wc_memory_entry wme; | |
913 | if (writecache_has_error(wc)) { | |
914 | e->original_sector = -1; | |
915 | e->seq_count = -1; | |
916 | continue; | |
917 | } | |
918 | r = memcpy_mcsafe(&wme, memory_entry(wc, e), sizeof(struct wc_memory_entry)); | |
919 | if (r) { | |
920 | writecache_error(wc, r, "hardware memory error when reading metadata entry %lu: %d", | |
921 | (unsigned long)b, r); | |
922 | e->original_sector = -1; | |
923 | e->seq_count = -1; | |
924 | } else { | |
925 | e->original_sector = le64_to_cpu(wme.original_sector); | |
926 | e->seq_count = le64_to_cpu(wme.seq_count); | |
927 | } | |
928 | } | |
929 | #endif | |
930 | for (b = 0; b < wc->n_blocks; b++) { | |
931 | struct wc_entry *e = &wc->entries[b]; | |
932 | if (!writecache_entry_is_committed(wc, e)) { | |
933 | if (read_seq_count(wc, e) != -1) { | |
934 | erase_this: | |
935 | clear_seq_count(wc, e); | |
936 | need_flush = true; | |
937 | } | |
938 | writecache_add_to_freelist(wc, e); | |
939 | } else { | |
940 | struct wc_entry *old; | |
941 | ||
942 | old = writecache_find_entry(wc, read_original_sector(wc, e), 0); | |
943 | if (!old) { | |
944 | writecache_insert_entry(wc, e); | |
945 | } else { | |
946 | if (read_seq_count(wc, old) == read_seq_count(wc, e)) { | |
947 | writecache_error(wc, -EINVAL, | |
948 | "two identical entries, position %llu, sector %llu, sequence %llu", | |
949 | (unsigned long long)b, (unsigned long long)read_original_sector(wc, e), | |
950 | (unsigned long long)read_seq_count(wc, e)); | |
951 | } | |
952 | if (read_seq_count(wc, old) > read_seq_count(wc, e)) { | |
953 | goto erase_this; | |
954 | } else { | |
955 | writecache_free_entry(wc, old); | |
956 | writecache_insert_entry(wc, e); | |
957 | need_flush = true; | |
958 | } | |
959 | } | |
960 | } | |
961 | cond_resched(); | |
962 | } | |
963 | ||
964 | if (need_flush) { | |
965 | writecache_flush_all_metadata(wc); | |
966 | writecache_commit_flushed(wc); | |
967 | } | |
968 | ||
969 | wc_unlock(wc); | |
970 | } | |
971 | ||
972 | static int process_flush_mesg(unsigned argc, char **argv, struct dm_writecache *wc) | |
973 | { | |
974 | if (argc != 1) | |
975 | return -EINVAL; | |
976 | ||
977 | wc_lock(wc); | |
978 | if (dm_suspended(wc->ti)) { | |
979 | wc_unlock(wc); | |
980 | return -EBUSY; | |
981 | } | |
982 | if (writecache_has_error(wc)) { | |
983 | wc_unlock(wc); | |
984 | return -EIO; | |
985 | } | |
986 | ||
987 | writecache_flush(wc); | |
988 | wc->writeback_all++; | |
989 | queue_work(wc->writeback_wq, &wc->writeback_work); | |
990 | wc_unlock(wc); | |
991 | ||
992 | flush_workqueue(wc->writeback_wq); | |
993 | ||
994 | wc_lock(wc); | |
995 | wc->writeback_all--; | |
996 | if (writecache_has_error(wc)) { | |
997 | wc_unlock(wc); | |
998 | return -EIO; | |
999 | } | |
1000 | wc_unlock(wc); | |
1001 | ||
1002 | return 0; | |
1003 | } | |
1004 | ||
1005 | static int process_flush_on_suspend_mesg(unsigned argc, char **argv, struct dm_writecache *wc) | |
1006 | { | |
1007 | if (argc != 1) | |
1008 | return -EINVAL; | |
1009 | ||
1010 | wc_lock(wc); | |
1011 | wc->flush_on_suspend = true; | |
1012 | wc_unlock(wc); | |
1013 | ||
1014 | return 0; | |
1015 | } | |
1016 | ||
1017 | static int writecache_message(struct dm_target *ti, unsigned argc, char **argv, | |
1018 | char *result, unsigned maxlen) | |
1019 | { | |
1020 | int r = -EINVAL; | |
1021 | struct dm_writecache *wc = ti->private; | |
1022 | ||
1023 | if (!strcasecmp(argv[0], "flush")) | |
1024 | r = process_flush_mesg(argc, argv, wc); | |
1025 | else if (!strcasecmp(argv[0], "flush_on_suspend")) | |
1026 | r = process_flush_on_suspend_mesg(argc, argv, wc); | |
1027 | else | |
1028 | DMERR("unrecognised message received: %s", argv[0]); | |
1029 | ||
1030 | return r; | |
1031 | } | |
1032 | ||
1033 | static void bio_copy_block(struct dm_writecache *wc, struct bio *bio, void *data) | |
1034 | { | |
1035 | void *buf; | |
1036 | unsigned long flags; | |
1037 | unsigned size; | |
1038 | int rw = bio_data_dir(bio); | |
1039 | unsigned remaining_size = wc->block_size; | |
1040 | ||
1041 | do { | |
1042 | struct bio_vec bv = bio_iter_iovec(bio, bio->bi_iter); | |
1043 | buf = bvec_kmap_irq(&bv, &flags); | |
1044 | size = bv.bv_len; | |
1045 | if (unlikely(size > remaining_size)) | |
1046 | size = remaining_size; | |
1047 | ||
1048 | if (rw == READ) { | |
1049 | int r; | |
1050 | r = memcpy_mcsafe(buf, data, size); | |
1051 | flush_dcache_page(bio_page(bio)); | |
1052 | if (unlikely(r)) { | |
1053 | writecache_error(wc, r, "hardware memory error when reading data: %d", r); | |
1054 | bio->bi_status = BLK_STS_IOERR; | |
1055 | } | |
1056 | } else { | |
1057 | flush_dcache_page(bio_page(bio)); | |
1058 | memcpy_flushcache(data, buf, size); | |
1059 | } | |
1060 | ||
1061 | bvec_kunmap_irq(buf, &flags); | |
1062 | ||
1063 | data = (char *)data + size; | |
1064 | remaining_size -= size; | |
1065 | bio_advance(bio, size); | |
1066 | } while (unlikely(remaining_size)); | |
1067 | } | |
1068 | ||
1069 | static int writecache_flush_thread(void *data) | |
1070 | { | |
1071 | struct dm_writecache *wc = data; | |
1072 | ||
1073 | while (1) { | |
1074 | struct bio *bio; | |
1075 | ||
1076 | wc_lock(wc); | |
1077 | bio = bio_list_pop(&wc->flush_list); | |
1078 | if (!bio) { | |
1079 | set_current_state(TASK_INTERRUPTIBLE); | |
1080 | wc_unlock(wc); | |
1081 | ||
1082 | if (unlikely(kthread_should_stop())) { | |
1083 | set_current_state(TASK_RUNNING); | |
1084 | break; | |
1085 | } | |
1086 | ||
1087 | schedule(); | |
1088 | continue; | |
1089 | } | |
1090 | ||
1091 | if (bio_op(bio) == REQ_OP_DISCARD) { | |
1092 | writecache_discard(wc, bio->bi_iter.bi_sector, | |
1093 | bio_end_sector(bio)); | |
1094 | wc_unlock(wc); | |
1095 | bio_set_dev(bio, wc->dev->bdev); | |
1096 | generic_make_request(bio); | |
1097 | } else { | |
1098 | writecache_flush(wc); | |
1099 | wc_unlock(wc); | |
1100 | if (writecache_has_error(wc)) | |
1101 | bio->bi_status = BLK_STS_IOERR; | |
1102 | bio_endio(bio); | |
1103 | } | |
1104 | } | |
1105 | ||
1106 | return 0; | |
1107 | } | |
1108 | ||
1109 | static void writecache_offload_bio(struct dm_writecache *wc, struct bio *bio) | |
1110 | { | |
1111 | if (bio_list_empty(&wc->flush_list)) | |
1112 | wake_up_process(wc->flush_thread); | |
1113 | bio_list_add(&wc->flush_list, bio); | |
1114 | } | |
1115 | ||
1116 | static int writecache_map(struct dm_target *ti, struct bio *bio) | |
1117 | { | |
1118 | struct wc_entry *e; | |
1119 | struct dm_writecache *wc = ti->private; | |
1120 | ||
1121 | bio->bi_private = NULL; | |
1122 | ||
1123 | wc_lock(wc); | |
1124 | ||
1125 | if (unlikely(bio->bi_opf & REQ_PREFLUSH)) { | |
1126 | if (writecache_has_error(wc)) | |
1127 | goto unlock_error; | |
1128 | if (WC_MODE_PMEM(wc)) { | |
1129 | writecache_flush(wc); | |
1130 | if (writecache_has_error(wc)) | |
1131 | goto unlock_error; | |
1132 | goto unlock_submit; | |
1133 | } else { | |
1134 | writecache_offload_bio(wc, bio); | |
1135 | goto unlock_return; | |
1136 | } | |
1137 | } | |
1138 | ||
1139 | bio->bi_iter.bi_sector = dm_target_offset(ti, bio->bi_iter.bi_sector); | |
1140 | ||
1141 | if (unlikely((((unsigned)bio->bi_iter.bi_sector | bio_sectors(bio)) & | |
1142 | (wc->block_size / 512 - 1)) != 0)) { | |
1143 | DMERR("I/O is not aligned, sector %llu, size %u, block size %u", | |
1144 | (unsigned long long)bio->bi_iter.bi_sector, | |
1145 | bio->bi_iter.bi_size, wc->block_size); | |
1146 | goto unlock_error; | |
1147 | } | |
1148 | ||
1149 | if (unlikely(bio_op(bio) == REQ_OP_DISCARD)) { | |
1150 | if (writecache_has_error(wc)) | |
1151 | goto unlock_error; | |
1152 | if (WC_MODE_PMEM(wc)) { | |
1153 | writecache_discard(wc, bio->bi_iter.bi_sector, bio_end_sector(bio)); | |
1154 | goto unlock_remap_origin; | |
1155 | } else { | |
1156 | writecache_offload_bio(wc, bio); | |
1157 | goto unlock_return; | |
1158 | } | |
1159 | } | |
1160 | ||
1161 | if (bio_data_dir(bio) == READ) { | |
1162 | read_next_block: | |
1163 | e = writecache_find_entry(wc, bio->bi_iter.bi_sector, WFE_RETURN_FOLLOWING); | |
1164 | if (e && read_original_sector(wc, e) == bio->bi_iter.bi_sector) { | |
1165 | if (WC_MODE_PMEM(wc)) { | |
1166 | bio_copy_block(wc, bio, memory_data(wc, e)); | |
1167 | if (bio->bi_iter.bi_size) | |
1168 | goto read_next_block; | |
1169 | goto unlock_submit; | |
1170 | } else { | |
1171 | dm_accept_partial_bio(bio, wc->block_size >> SECTOR_SHIFT); | |
1172 | bio_set_dev(bio, wc->ssd_dev->bdev); | |
1173 | bio->bi_iter.bi_sector = cache_sector(wc, e); | |
1174 | if (!writecache_entry_is_committed(wc, e)) | |
1175 | writecache_wait_for_ios(wc, WRITE); | |
1176 | goto unlock_remap; | |
1177 | } | |
1178 | } else { | |
1179 | if (e) { | |
1180 | sector_t next_boundary = | |
1181 | read_original_sector(wc, e) - bio->bi_iter.bi_sector; | |
1182 | if (next_boundary < bio->bi_iter.bi_size >> SECTOR_SHIFT) { | |
1183 | dm_accept_partial_bio(bio, next_boundary); | |
1184 | } | |
1185 | } | |
1186 | goto unlock_remap_origin; | |
1187 | } | |
1188 | } else { | |
1189 | do { | |
1190 | if (writecache_has_error(wc)) | |
1191 | goto unlock_error; | |
1192 | e = writecache_find_entry(wc, bio->bi_iter.bi_sector, 0); | |
1193 | if (e) { | |
1194 | if (!writecache_entry_is_committed(wc, e)) | |
1195 | goto bio_copy; | |
1196 | if (!WC_MODE_PMEM(wc) && !e->write_in_progress) { | |
1197 | wc->overwrote_committed = true; | |
1198 | goto bio_copy; | |
1199 | } | |
1200 | } | |
1201 | e = writecache_pop_from_freelist(wc); | |
1202 | if (unlikely(!e)) { | |
1203 | writecache_wait_on_freelist(wc); | |
1204 | continue; | |
1205 | } | |
1206 | write_original_sector_seq_count(wc, e, bio->bi_iter.bi_sector, wc->seq_count); | |
1207 | writecache_insert_entry(wc, e); | |
1208 | wc->uncommitted_blocks++; | |
1209 | bio_copy: | |
1210 | if (WC_MODE_PMEM(wc)) { | |
1211 | bio_copy_block(wc, bio, memory_data(wc, e)); | |
1212 | } else { | |
1213 | dm_accept_partial_bio(bio, wc->block_size >> SECTOR_SHIFT); | |
1214 | bio_set_dev(bio, wc->ssd_dev->bdev); | |
1215 | bio->bi_iter.bi_sector = cache_sector(wc, e); | |
1216 | if (unlikely(wc->uncommitted_blocks >= wc->autocommit_blocks)) { | |
1217 | wc->uncommitted_blocks = 0; | |
1218 | queue_work(wc->writeback_wq, &wc->flush_work); | |
1219 | } else { | |
1220 | writecache_schedule_autocommit(wc); | |
1221 | } | |
1222 | goto unlock_remap; | |
1223 | } | |
1224 | } while (bio->bi_iter.bi_size); | |
1225 | ||
1226 | if (unlikely(wc->uncommitted_blocks >= wc->autocommit_blocks)) | |
1227 | writecache_flush(wc); | |
1228 | else | |
1229 | writecache_schedule_autocommit(wc); | |
1230 | goto unlock_submit; | |
1231 | } | |
1232 | ||
1233 | unlock_remap_origin: | |
1234 | bio_set_dev(bio, wc->dev->bdev); | |
1235 | wc_unlock(wc); | |
1236 | return DM_MAPIO_REMAPPED; | |
1237 | ||
1238 | unlock_remap: | |
1239 | /* make sure that writecache_end_io decrements bio_in_progress: */ | |
1240 | bio->bi_private = (void *)1; | |
1241 | atomic_inc(&wc->bio_in_progress[bio_data_dir(bio)]); | |
1242 | wc_unlock(wc); | |
1243 | return DM_MAPIO_REMAPPED; | |
1244 | ||
1245 | unlock_submit: | |
1246 | wc_unlock(wc); | |
1247 | bio_endio(bio); | |
1248 | return DM_MAPIO_SUBMITTED; | |
1249 | ||
1250 | unlock_return: | |
1251 | wc_unlock(wc); | |
1252 | return DM_MAPIO_SUBMITTED; | |
1253 | ||
1254 | unlock_error: | |
1255 | wc_unlock(wc); | |
1256 | bio_io_error(bio); | |
1257 | return DM_MAPIO_SUBMITTED; | |
1258 | } | |
1259 | ||
1260 | static int writecache_end_io(struct dm_target *ti, struct bio *bio, blk_status_t *status) | |
1261 | { | |
1262 | struct dm_writecache *wc = ti->private; | |
1263 | ||
1264 | if (bio->bi_private != NULL) { | |
1265 | int dir = bio_data_dir(bio); | |
1266 | if (atomic_dec_and_test(&wc->bio_in_progress[dir])) | |
1267 | if (unlikely(waitqueue_active(&wc->bio_in_progress_wait[dir]))) | |
1268 | wake_up(&wc->bio_in_progress_wait[dir]); | |
1269 | } | |
1270 | return 0; | |
1271 | } | |
1272 | ||
1273 | static int writecache_iterate_devices(struct dm_target *ti, | |
1274 | iterate_devices_callout_fn fn, void *data) | |
1275 | { | |
1276 | struct dm_writecache *wc = ti->private; | |
1277 | ||
1278 | return fn(ti, wc->dev, 0, ti->len, data); | |
1279 | } | |
1280 | ||
1281 | static void writecache_io_hints(struct dm_target *ti, struct queue_limits *limits) | |
1282 | { | |
1283 | struct dm_writecache *wc = ti->private; | |
1284 | ||
1285 | if (limits->logical_block_size < wc->block_size) | |
1286 | limits->logical_block_size = wc->block_size; | |
1287 | ||
1288 | if (limits->physical_block_size < wc->block_size) | |
1289 | limits->physical_block_size = wc->block_size; | |
1290 | ||
1291 | if (limits->io_min < wc->block_size) | |
1292 | limits->io_min = wc->block_size; | |
1293 | } | |
1294 | ||
1295 | ||
1296 | static void writecache_writeback_endio(struct bio *bio) | |
1297 | { | |
1298 | struct writeback_struct *wb = container_of(bio, struct writeback_struct, bio); | |
1299 | struct dm_writecache *wc = wb->wc; | |
1300 | unsigned long flags; | |
1301 | ||
1302 | raw_spin_lock_irqsave(&wc->endio_list_lock, flags); | |
1303 | if (unlikely(list_empty(&wc->endio_list))) | |
1304 | wake_up_process(wc->endio_thread); | |
1305 | list_add_tail(&wb->endio_entry, &wc->endio_list); | |
1306 | raw_spin_unlock_irqrestore(&wc->endio_list_lock, flags); | |
1307 | } | |
1308 | ||
1309 | static void writecache_copy_endio(int read_err, unsigned long write_err, void *ptr) | |
1310 | { | |
1311 | struct copy_struct *c = ptr; | |
1312 | struct dm_writecache *wc = c->wc; | |
1313 | ||
1314 | c->error = likely(!(read_err | write_err)) ? 0 : -EIO; | |
1315 | ||
1316 | raw_spin_lock_irq(&wc->endio_list_lock); | |
1317 | if (unlikely(list_empty(&wc->endio_list))) | |
1318 | wake_up_process(wc->endio_thread); | |
1319 | list_add_tail(&c->endio_entry, &wc->endio_list); | |
1320 | raw_spin_unlock_irq(&wc->endio_list_lock); | |
1321 | } | |
1322 | ||
1323 | static void __writecache_endio_pmem(struct dm_writecache *wc, struct list_head *list) | |
1324 | { | |
1325 | unsigned i; | |
1326 | struct writeback_struct *wb; | |
1327 | struct wc_entry *e; | |
1328 | unsigned long n_walked = 0; | |
1329 | ||
1330 | do { | |
1331 | wb = list_entry(list->next, struct writeback_struct, endio_entry); | |
1332 | list_del(&wb->endio_entry); | |
1333 | ||
1334 | if (unlikely(wb->bio.bi_status != BLK_STS_OK)) | |
1335 | writecache_error(wc, blk_status_to_errno(wb->bio.bi_status), | |
1336 | "write error %d", wb->bio.bi_status); | |
1337 | i = 0; | |
1338 | do { | |
1339 | e = wb->wc_list[i]; | |
1340 | BUG_ON(!e->write_in_progress); | |
1341 | e->write_in_progress = false; | |
1342 | INIT_LIST_HEAD(&e->lru); | |
1343 | if (!writecache_has_error(wc)) | |
1344 | writecache_free_entry(wc, e); | |
1345 | BUG_ON(!wc->writeback_size); | |
1346 | wc->writeback_size--; | |
1347 | n_walked++; | |
1348 | if (unlikely(n_walked >= ENDIO_LATENCY)) { | |
1349 | writecache_commit_flushed(wc); | |
1350 | wc_unlock(wc); | |
1351 | wc_lock(wc); | |
1352 | n_walked = 0; | |
1353 | } | |
1354 | } while (++i < wb->wc_list_n); | |
1355 | ||
1356 | if (wb->wc_list != wb->wc_list_inline) | |
1357 | kfree(wb->wc_list); | |
1358 | bio_put(&wb->bio); | |
1359 | } while (!list_empty(list)); | |
1360 | } | |
1361 | ||
1362 | static void __writecache_endio_ssd(struct dm_writecache *wc, struct list_head *list) | |
1363 | { | |
1364 | struct copy_struct *c; | |
1365 | struct wc_entry *e; | |
1366 | ||
1367 | do { | |
1368 | c = list_entry(list->next, struct copy_struct, endio_entry); | |
1369 | list_del(&c->endio_entry); | |
1370 | ||
1371 | if (unlikely(c->error)) | |
1372 | writecache_error(wc, c->error, "copy error"); | |
1373 | ||
1374 | e = c->e; | |
1375 | do { | |
1376 | BUG_ON(!e->write_in_progress); | |
1377 | e->write_in_progress = false; | |
1378 | INIT_LIST_HEAD(&e->lru); | |
1379 | if (!writecache_has_error(wc)) | |
1380 | writecache_free_entry(wc, e); | |
1381 | ||
1382 | BUG_ON(!wc->writeback_size); | |
1383 | wc->writeback_size--; | |
1384 | e++; | |
1385 | } while (--c->n_entries); | |
1386 | mempool_free(c, &wc->copy_pool); | |
1387 | } while (!list_empty(list)); | |
1388 | } | |
1389 | ||
1390 | static int writecache_endio_thread(void *data) | |
1391 | { | |
1392 | struct dm_writecache *wc = data; | |
1393 | ||
1394 | while (1) { | |
1395 | struct list_head list; | |
1396 | ||
1397 | raw_spin_lock_irq(&wc->endio_list_lock); | |
1398 | if (!list_empty(&wc->endio_list)) | |
1399 | goto pop_from_list; | |
1400 | set_current_state(TASK_INTERRUPTIBLE); | |
1401 | raw_spin_unlock_irq(&wc->endio_list_lock); | |
1402 | ||
1403 | if (unlikely(kthread_should_stop())) { | |
1404 | set_current_state(TASK_RUNNING); | |
1405 | break; | |
1406 | } | |
1407 | ||
1408 | schedule(); | |
1409 | ||
1410 | continue; | |
1411 | ||
1412 | pop_from_list: | |
1413 | list = wc->endio_list; | |
1414 | list.next->prev = list.prev->next = &list; | |
1415 | INIT_LIST_HEAD(&wc->endio_list); | |
1416 | raw_spin_unlock_irq(&wc->endio_list_lock); | |
1417 | ||
1418 | if (!WC_MODE_FUA(wc)) | |
1419 | writecache_disk_flush(wc, wc->dev); | |
1420 | ||
1421 | wc_lock(wc); | |
1422 | ||
1423 | if (WC_MODE_PMEM(wc)) { | |
1424 | __writecache_endio_pmem(wc, &list); | |
1425 | } else { | |
1426 | __writecache_endio_ssd(wc, &list); | |
1427 | writecache_wait_for_ios(wc, READ); | |
1428 | } | |
1429 | ||
1430 | writecache_commit_flushed(wc); | |
1431 | ||
1432 | wc_unlock(wc); | |
1433 | } | |
1434 | ||
1435 | return 0; | |
1436 | } | |
1437 | ||
1438 | static bool wc_add_block(struct writeback_struct *wb, struct wc_entry *e, gfp_t gfp) | |
1439 | { | |
1440 | struct dm_writecache *wc = wb->wc; | |
1441 | unsigned block_size = wc->block_size; | |
1442 | void *address = memory_data(wc, e); | |
1443 | ||
1444 | persistent_memory_flush_cache(address, block_size); | |
1445 | return bio_add_page(&wb->bio, persistent_memory_page(address), | |
1446 | block_size, persistent_memory_page_offset(address)) != 0; | |
1447 | } | |
1448 | ||
1449 | struct writeback_list { | |
1450 | struct list_head list; | |
1451 | size_t size; | |
1452 | }; | |
1453 | ||
1454 | static void __writeback_throttle(struct dm_writecache *wc, struct writeback_list *wbl) | |
1455 | { | |
1456 | if (unlikely(wc->max_writeback_jobs)) { | |
1457 | if (READ_ONCE(wc->writeback_size) - wbl->size >= wc->max_writeback_jobs) { | |
1458 | wc_lock(wc); | |
1459 | while (wc->writeback_size - wbl->size >= wc->max_writeback_jobs) | |
1460 | writecache_wait_on_freelist(wc); | |
1461 | wc_unlock(wc); | |
1462 | } | |
1463 | } | |
1464 | cond_resched(); | |
1465 | } | |
1466 | ||
1467 | static void __writecache_writeback_pmem(struct dm_writecache *wc, struct writeback_list *wbl) | |
1468 | { | |
1469 | struct wc_entry *e, *f; | |
1470 | struct bio *bio; | |
1471 | struct writeback_struct *wb; | |
1472 | unsigned max_pages; | |
1473 | ||
1474 | while (wbl->size) { | |
1475 | wbl->size--; | |
1476 | e = container_of(wbl->list.prev, struct wc_entry, lru); | |
1477 | list_del(&e->lru); | |
1478 | ||
1479 | max_pages = e->wc_list_contiguous; | |
1480 | ||
1481 | bio = bio_alloc_bioset(GFP_NOIO, max_pages, &wc->bio_set); | |
1482 | wb = container_of(bio, struct writeback_struct, bio); | |
1483 | wb->wc = wc; | |
1484 | wb->bio.bi_end_io = writecache_writeback_endio; | |
1485 | bio_set_dev(&wb->bio, wc->dev->bdev); | |
1486 | wb->bio.bi_iter.bi_sector = read_original_sector(wc, e); | |
1487 | wb->page_offset = PAGE_SIZE; | |
1488 | if (max_pages <= WB_LIST_INLINE || | |
50a7d3ba KC |
1489 | unlikely(!(wb->wc_list = kmalloc_array(max_pages, sizeof(struct wc_entry *), |
1490 | GFP_NOIO | __GFP_NORETRY | | |
1491 | __GFP_NOMEMALLOC | __GFP_NOWARN)))) { | |
48debafe MP |
1492 | wb->wc_list = wb->wc_list_inline; |
1493 | max_pages = WB_LIST_INLINE; | |
1494 | } | |
1495 | ||
1496 | BUG_ON(!wc_add_block(wb, e, GFP_NOIO)); | |
1497 | ||
1498 | wb->wc_list[0] = e; | |
1499 | wb->wc_list_n = 1; | |
1500 | ||
1501 | while (wbl->size && wb->wc_list_n < max_pages) { | |
1502 | f = container_of(wbl->list.prev, struct wc_entry, lru); | |
1503 | if (read_original_sector(wc, f) != | |
1504 | read_original_sector(wc, e) + (wc->block_size >> SECTOR_SHIFT)) | |
1505 | break; | |
1506 | if (!wc_add_block(wb, f, GFP_NOWAIT | __GFP_NOWARN)) | |
1507 | break; | |
1508 | wbl->size--; | |
1509 | list_del(&f->lru); | |
1510 | wb->wc_list[wb->wc_list_n++] = f; | |
1511 | e = f; | |
1512 | } | |
1513 | bio_set_op_attrs(&wb->bio, REQ_OP_WRITE, WC_MODE_FUA(wc) * REQ_FUA); | |
1514 | if (writecache_has_error(wc)) { | |
1515 | bio->bi_status = BLK_STS_IOERR; | |
1516 | bio_endio(&wb->bio); | |
1517 | } else { | |
1518 | submit_bio(&wb->bio); | |
1519 | } | |
1520 | ||
1521 | __writeback_throttle(wc, wbl); | |
1522 | } | |
1523 | } | |
1524 | ||
1525 | static void __writecache_writeback_ssd(struct dm_writecache *wc, struct writeback_list *wbl) | |
1526 | { | |
1527 | struct wc_entry *e, *f; | |
1528 | struct dm_io_region from, to; | |
1529 | struct copy_struct *c; | |
1530 | ||
1531 | while (wbl->size) { | |
1532 | unsigned n_sectors; | |
1533 | ||
1534 | wbl->size--; | |
1535 | e = container_of(wbl->list.prev, struct wc_entry, lru); | |
1536 | list_del(&e->lru); | |
1537 | ||
1538 | n_sectors = e->wc_list_contiguous << (wc->block_size_bits - SECTOR_SHIFT); | |
1539 | ||
1540 | from.bdev = wc->ssd_dev->bdev; | |
1541 | from.sector = cache_sector(wc, e); | |
1542 | from.count = n_sectors; | |
1543 | to.bdev = wc->dev->bdev; | |
1544 | to.sector = read_original_sector(wc, e); | |
1545 | to.count = n_sectors; | |
1546 | ||
1547 | c = mempool_alloc(&wc->copy_pool, GFP_NOIO); | |
1548 | c->wc = wc; | |
1549 | c->e = e; | |
1550 | c->n_entries = e->wc_list_contiguous; | |
1551 | ||
1552 | while ((n_sectors -= wc->block_size >> SECTOR_SHIFT)) { | |
1553 | wbl->size--; | |
1554 | f = container_of(wbl->list.prev, struct wc_entry, lru); | |
1555 | BUG_ON(f != e + 1); | |
1556 | list_del(&f->lru); | |
1557 | e = f; | |
1558 | } | |
1559 | ||
1560 | dm_kcopyd_copy(wc->dm_kcopyd, &from, 1, &to, 0, writecache_copy_endio, c); | |
1561 | ||
1562 | __writeback_throttle(wc, wbl); | |
1563 | } | |
1564 | } | |
1565 | ||
1566 | static void writecache_writeback(struct work_struct *work) | |
1567 | { | |
1568 | struct dm_writecache *wc = container_of(work, struct dm_writecache, writeback_work); | |
1569 | struct blk_plug plug; | |
1570 | struct wc_entry *e, *f, *g; | |
1571 | struct rb_node *node, *next_node; | |
1572 | struct list_head skipped; | |
1573 | struct writeback_list wbl; | |
1574 | unsigned long n_walked; | |
1575 | ||
1576 | wc_lock(wc); | |
1577 | restart: | |
1578 | if (writecache_has_error(wc)) { | |
1579 | wc_unlock(wc); | |
1580 | return; | |
1581 | } | |
1582 | ||
1583 | if (unlikely(wc->writeback_all)) { | |
1584 | if (writecache_wait_for_writeback(wc)) | |
1585 | goto restart; | |
1586 | } | |
1587 | ||
1588 | if (wc->overwrote_committed) { | |
1589 | writecache_wait_for_ios(wc, WRITE); | |
1590 | } | |
1591 | ||
1592 | n_walked = 0; | |
1593 | INIT_LIST_HEAD(&skipped); | |
1594 | INIT_LIST_HEAD(&wbl.list); | |
1595 | wbl.size = 0; | |
1596 | while (!list_empty(&wc->lru) && | |
1597 | (wc->writeback_all || | |
1598 | wc->freelist_size + wc->writeback_size <= wc->freelist_low_watermark)) { | |
1599 | ||
1600 | n_walked++; | |
1601 | if (unlikely(n_walked > WRITEBACK_LATENCY) && | |
1602 | likely(!wc->writeback_all) && likely(!dm_suspended(wc->ti))) { | |
1603 | queue_work(wc->writeback_wq, &wc->writeback_work); | |
1604 | break; | |
1605 | } | |
1606 | ||
1607 | e = container_of(wc->lru.prev, struct wc_entry, lru); | |
1608 | BUG_ON(e->write_in_progress); | |
1609 | if (unlikely(!writecache_entry_is_committed(wc, e))) { | |
1610 | writecache_flush(wc); | |
1611 | } | |
1612 | node = rb_prev(&e->rb_node); | |
1613 | if (node) { | |
1614 | f = container_of(node, struct wc_entry, rb_node); | |
1615 | if (unlikely(read_original_sector(wc, f) == | |
1616 | read_original_sector(wc, e))) { | |
1617 | BUG_ON(!f->write_in_progress); | |
1618 | list_del(&e->lru); | |
1619 | list_add(&e->lru, &skipped); | |
1620 | cond_resched(); | |
1621 | continue; | |
1622 | } | |
1623 | } | |
1624 | wc->writeback_size++; | |
1625 | list_del(&e->lru); | |
1626 | list_add(&e->lru, &wbl.list); | |
1627 | wbl.size++; | |
1628 | e->write_in_progress = true; | |
1629 | e->wc_list_contiguous = 1; | |
1630 | ||
1631 | f = e; | |
1632 | ||
1633 | while (1) { | |
1634 | next_node = rb_next(&f->rb_node); | |
1635 | if (unlikely(!next_node)) | |
1636 | break; | |
1637 | g = container_of(next_node, struct wc_entry, rb_node); | |
1638 | if (read_original_sector(wc, g) == | |
1639 | read_original_sector(wc, f)) { | |
1640 | f = g; | |
1641 | continue; | |
1642 | } | |
1643 | if (read_original_sector(wc, g) != | |
1644 | read_original_sector(wc, f) + (wc->block_size >> SECTOR_SHIFT)) | |
1645 | break; | |
1646 | if (unlikely(g->write_in_progress)) | |
1647 | break; | |
1648 | if (unlikely(!writecache_entry_is_committed(wc, g))) | |
1649 | break; | |
1650 | ||
1651 | if (!WC_MODE_PMEM(wc)) { | |
1652 | if (g != f + 1) | |
1653 | break; | |
1654 | } | |
1655 | ||
1656 | n_walked++; | |
1657 | //if (unlikely(n_walked > WRITEBACK_LATENCY) && likely(!wc->writeback_all)) | |
1658 | // break; | |
1659 | ||
1660 | wc->writeback_size++; | |
1661 | list_del(&g->lru); | |
1662 | list_add(&g->lru, &wbl.list); | |
1663 | wbl.size++; | |
1664 | g->write_in_progress = true; | |
1665 | g->wc_list_contiguous = BIO_MAX_PAGES; | |
1666 | f = g; | |
1667 | e->wc_list_contiguous++; | |
1668 | if (unlikely(e->wc_list_contiguous == BIO_MAX_PAGES)) | |
1669 | break; | |
1670 | } | |
1671 | cond_resched(); | |
1672 | } | |
1673 | ||
1674 | if (!list_empty(&skipped)) { | |
1675 | list_splice_tail(&skipped, &wc->lru); | |
1676 | /* | |
1677 | * If we didn't do any progress, we must wait until some | |
1678 | * writeback finishes to avoid burning CPU in a loop | |
1679 | */ | |
1680 | if (unlikely(!wbl.size)) | |
1681 | writecache_wait_for_writeback(wc); | |
1682 | } | |
1683 | ||
1684 | wc_unlock(wc); | |
1685 | ||
1686 | blk_start_plug(&plug); | |
1687 | ||
1688 | if (WC_MODE_PMEM(wc)) | |
1689 | __writecache_writeback_pmem(wc, &wbl); | |
1690 | else | |
1691 | __writecache_writeback_ssd(wc, &wbl); | |
1692 | ||
1693 | blk_finish_plug(&plug); | |
1694 | ||
1695 | if (unlikely(wc->writeback_all)) { | |
1696 | wc_lock(wc); | |
1697 | while (writecache_wait_for_writeback(wc)); | |
1698 | wc_unlock(wc); | |
1699 | } | |
1700 | } | |
1701 | ||
1702 | static int calculate_memory_size(uint64_t device_size, unsigned block_size, | |
1703 | size_t *n_blocks_p, size_t *n_metadata_blocks_p) | |
1704 | { | |
1705 | uint64_t n_blocks, offset; | |
1706 | struct wc_entry e; | |
1707 | ||
1708 | n_blocks = device_size; | |
1709 | do_div(n_blocks, block_size + sizeof(struct wc_memory_entry)); | |
1710 | ||
1711 | while (1) { | |
1712 | if (!n_blocks) | |
1713 | return -ENOSPC; | |
1714 | /* Verify the following entries[n_blocks] won't overflow */ | |
1715 | if (n_blocks >= ((size_t)-sizeof(struct wc_memory_superblock) / | |
1716 | sizeof(struct wc_memory_entry))) | |
1717 | return -EFBIG; | |
1718 | offset = offsetof(struct wc_memory_superblock, entries[n_blocks]); | |
1719 | offset = (offset + block_size - 1) & ~(uint64_t)(block_size - 1); | |
1720 | if (offset + n_blocks * block_size <= device_size) | |
1721 | break; | |
1722 | n_blocks--; | |
1723 | } | |
1724 | ||
1725 | /* check if the bit field overflows */ | |
1726 | e.index = n_blocks; | |
1727 | if (e.index != n_blocks) | |
1728 | return -EFBIG; | |
1729 | ||
1730 | if (n_blocks_p) | |
1731 | *n_blocks_p = n_blocks; | |
1732 | if (n_metadata_blocks_p) | |
1733 | *n_metadata_blocks_p = offset >> __ffs(block_size); | |
1734 | return 0; | |
1735 | } | |
1736 | ||
1737 | static int init_memory(struct dm_writecache *wc) | |
1738 | { | |
1739 | size_t b; | |
1740 | int r; | |
1741 | ||
1742 | r = calculate_memory_size(wc->memory_map_size, wc->block_size, &wc->n_blocks, NULL); | |
1743 | if (r) | |
1744 | return r; | |
1745 | ||
1746 | r = writecache_alloc_entries(wc); | |
1747 | if (r) | |
1748 | return r; | |
1749 | ||
1750 | for (b = 0; b < ARRAY_SIZE(sb(wc)->padding); b++) | |
1751 | pmem_assign(sb(wc)->padding[b], cpu_to_le64(0)); | |
1752 | pmem_assign(sb(wc)->version, cpu_to_le32(MEMORY_SUPERBLOCK_VERSION)); | |
1753 | pmem_assign(sb(wc)->block_size, cpu_to_le32(wc->block_size)); | |
1754 | pmem_assign(sb(wc)->n_blocks, cpu_to_le64(wc->n_blocks)); | |
1755 | pmem_assign(sb(wc)->seq_count, cpu_to_le64(0)); | |
1756 | ||
1757 | for (b = 0; b < wc->n_blocks; b++) | |
1758 | write_original_sector_seq_count(wc, &wc->entries[b], -1, -1); | |
1759 | ||
1760 | writecache_flush_all_metadata(wc); | |
1761 | writecache_commit_flushed(wc); | |
1762 | pmem_assign(sb(wc)->magic, cpu_to_le32(MEMORY_SUPERBLOCK_MAGIC)); | |
1763 | writecache_flush_region(wc, &sb(wc)->magic, sizeof sb(wc)->magic); | |
1764 | writecache_commit_flushed(wc); | |
1765 | ||
1766 | return 0; | |
1767 | } | |
1768 | ||
1769 | static void writecache_dtr(struct dm_target *ti) | |
1770 | { | |
1771 | struct dm_writecache *wc = ti->private; | |
1772 | ||
1773 | if (!wc) | |
1774 | return; | |
1775 | ||
1776 | if (wc->endio_thread) | |
1777 | kthread_stop(wc->endio_thread); | |
1778 | ||
1779 | if (wc->flush_thread) | |
1780 | kthread_stop(wc->flush_thread); | |
1781 | ||
1782 | bioset_exit(&wc->bio_set); | |
1783 | ||
1784 | mempool_exit(&wc->copy_pool); | |
1785 | ||
1786 | if (wc->writeback_wq) | |
1787 | destroy_workqueue(wc->writeback_wq); | |
1788 | ||
1789 | if (wc->dev) | |
1790 | dm_put_device(ti, wc->dev); | |
1791 | ||
1792 | if (wc->ssd_dev) | |
1793 | dm_put_device(ti, wc->ssd_dev); | |
1794 | ||
1795 | if (wc->entries) | |
1796 | vfree(wc->entries); | |
1797 | ||
1798 | if (wc->memory_map) { | |
1799 | if (WC_MODE_PMEM(wc)) | |
1800 | persistent_memory_release(wc); | |
1801 | else | |
1802 | vfree(wc->memory_map); | |
1803 | } | |
1804 | ||
1805 | if (wc->dm_kcopyd) | |
1806 | dm_kcopyd_client_destroy(wc->dm_kcopyd); | |
1807 | ||
1808 | if (wc->dm_io) | |
1809 | dm_io_client_destroy(wc->dm_io); | |
1810 | ||
1811 | if (wc->dirty_bitmap) | |
1812 | vfree(wc->dirty_bitmap); | |
1813 | ||
1814 | kfree(wc); | |
1815 | } | |
1816 | ||
1817 | static int writecache_ctr(struct dm_target *ti, unsigned argc, char **argv) | |
1818 | { | |
1819 | struct dm_writecache *wc; | |
1820 | struct dm_arg_set as; | |
1821 | const char *string; | |
1822 | unsigned opt_params; | |
1823 | size_t offset, data_size; | |
1824 | int i, r; | |
1825 | char dummy; | |
1826 | int high_wm_percent = HIGH_WATERMARK; | |
1827 | int low_wm_percent = LOW_WATERMARK; | |
1828 | uint64_t x; | |
1829 | struct wc_memory_superblock s; | |
1830 | ||
1831 | static struct dm_arg _args[] = { | |
1832 | {0, 10, "Invalid number of feature args"}, | |
1833 | }; | |
1834 | ||
1835 | as.argc = argc; | |
1836 | as.argv = argv; | |
1837 | ||
1838 | wc = kzalloc(sizeof(struct dm_writecache), GFP_KERNEL); | |
1839 | if (!wc) { | |
1840 | ti->error = "Cannot allocate writecache structure"; | |
1841 | r = -ENOMEM; | |
1842 | goto bad; | |
1843 | } | |
1844 | ti->private = wc; | |
1845 | wc->ti = ti; | |
1846 | ||
1847 | mutex_init(&wc->lock); | |
1848 | writecache_poison_lists(wc); | |
1849 | init_waitqueue_head(&wc->freelist_wait); | |
1850 | timer_setup(&wc->autocommit_timer, writecache_autocommit_timer, 0); | |
1851 | ||
1852 | for (i = 0; i < 2; i++) { | |
1853 | atomic_set(&wc->bio_in_progress[i], 0); | |
1854 | init_waitqueue_head(&wc->bio_in_progress_wait[i]); | |
1855 | } | |
1856 | ||
1857 | wc->dm_io = dm_io_client_create(); | |
1858 | if (IS_ERR(wc->dm_io)) { | |
1859 | r = PTR_ERR(wc->dm_io); | |
1860 | ti->error = "Unable to allocate dm-io client"; | |
1861 | wc->dm_io = NULL; | |
1862 | goto bad; | |
1863 | } | |
1864 | ||
1865 | wc->writeback_wq = alloc_workqueue("writecache-writeabck", WQ_MEM_RECLAIM, 1); | |
1866 | if (!wc->writeback_wq) { | |
1867 | r = -ENOMEM; | |
1868 | ti->error = "Could not allocate writeback workqueue"; | |
1869 | goto bad; | |
1870 | } | |
1871 | INIT_WORK(&wc->writeback_work, writecache_writeback); | |
1872 | INIT_WORK(&wc->flush_work, writecache_flush_work); | |
1873 | ||
1874 | raw_spin_lock_init(&wc->endio_list_lock); | |
1875 | INIT_LIST_HEAD(&wc->endio_list); | |
1876 | wc->endio_thread = kthread_create(writecache_endio_thread, wc, "writecache_endio"); | |
1877 | if (IS_ERR(wc->endio_thread)) { | |
1878 | r = PTR_ERR(wc->endio_thread); | |
1879 | wc->endio_thread = NULL; | |
1880 | ti->error = "Couldn't spawn endio thread"; | |
1881 | goto bad; | |
1882 | } | |
1883 | wake_up_process(wc->endio_thread); | |
1884 | ||
1885 | /* | |
1886 | * Parse the mode (pmem or ssd) | |
1887 | */ | |
1888 | string = dm_shift_arg(&as); | |
1889 | if (!string) | |
1890 | goto bad_arguments; | |
1891 | ||
1892 | if (!strcasecmp(string, "s")) { | |
1893 | wc->pmem_mode = false; | |
1894 | } else if (!strcasecmp(string, "p")) { | |
1895 | #ifdef DM_WRITECACHE_HAS_PMEM | |
1896 | wc->pmem_mode = true; | |
1897 | wc->writeback_fua = true; | |
1898 | #else | |
1899 | /* | |
1900 | * If the architecture doesn't support persistent memory or | |
1901 | * the kernel doesn't support any DAX drivers, this driver can | |
1902 | * only be used in SSD-only mode. | |
1903 | */ | |
1904 | r = -EOPNOTSUPP; | |
1905 | ti->error = "Persistent memory or DAX not supported on this system"; | |
1906 | goto bad; | |
1907 | #endif | |
1908 | } else { | |
1909 | goto bad_arguments; | |
1910 | } | |
1911 | ||
1912 | if (WC_MODE_PMEM(wc)) { | |
1913 | r = bioset_init(&wc->bio_set, BIO_POOL_SIZE, | |
1914 | offsetof(struct writeback_struct, bio), | |
1915 | BIOSET_NEED_BVECS); | |
1916 | if (r) { | |
1917 | ti->error = "Could not allocate bio set"; | |
1918 | goto bad; | |
1919 | } | |
1920 | } else { | |
1921 | r = mempool_init_kmalloc_pool(&wc->copy_pool, 1, sizeof(struct copy_struct)); | |
1922 | if (r) { | |
1923 | ti->error = "Could not allocate mempool"; | |
1924 | goto bad; | |
1925 | } | |
1926 | } | |
1927 | ||
1928 | /* | |
1929 | * Parse the origin data device | |
1930 | */ | |
1931 | string = dm_shift_arg(&as); | |
1932 | if (!string) | |
1933 | goto bad_arguments; | |
1934 | r = dm_get_device(ti, string, dm_table_get_mode(ti->table), &wc->dev); | |
1935 | if (r) { | |
1936 | ti->error = "Origin data device lookup failed"; | |
1937 | goto bad; | |
1938 | } | |
1939 | ||
1940 | /* | |
1941 | * Parse cache data device (be it pmem or ssd) | |
1942 | */ | |
1943 | string = dm_shift_arg(&as); | |
1944 | if (!string) | |
1945 | goto bad_arguments; | |
1946 | ||
1947 | r = dm_get_device(ti, string, dm_table_get_mode(ti->table), &wc->ssd_dev); | |
1948 | if (r) { | |
1949 | ti->error = "Cache data device lookup failed"; | |
1950 | goto bad; | |
1951 | } | |
1952 | wc->memory_map_size = i_size_read(wc->ssd_dev->bdev->bd_inode); | |
1953 | ||
48debafe MP |
1954 | /* |
1955 | * Parse the cache block size | |
1956 | */ | |
1957 | string = dm_shift_arg(&as); | |
1958 | if (!string) | |
1959 | goto bad_arguments; | |
1960 | if (sscanf(string, "%u%c", &wc->block_size, &dummy) != 1 || | |
1961 | wc->block_size < 512 || wc->block_size > PAGE_SIZE || | |
1962 | (wc->block_size & (wc->block_size - 1))) { | |
1963 | r = -EINVAL; | |
1964 | ti->error = "Invalid block size"; | |
1965 | goto bad; | |
1966 | } | |
1967 | wc->block_size_bits = __ffs(wc->block_size); | |
1968 | ||
1969 | wc->max_writeback_jobs = MAX_WRITEBACK_JOBS; | |
1970 | wc->autocommit_blocks = !WC_MODE_PMEM(wc) ? AUTOCOMMIT_BLOCKS_SSD : AUTOCOMMIT_BLOCKS_PMEM; | |
1971 | wc->autocommit_jiffies = msecs_to_jiffies(AUTOCOMMIT_MSEC); | |
1972 | ||
1973 | /* | |
1974 | * Parse optional arguments | |
1975 | */ | |
1976 | r = dm_read_arg_group(_args, &as, &opt_params, &ti->error); | |
1977 | if (r) | |
1978 | goto bad; | |
1979 | ||
1980 | while (opt_params) { | |
1981 | string = dm_shift_arg(&as), opt_params--; | |
d284f824 MP |
1982 | if (!strcasecmp(string, "start_sector") && opt_params >= 1) { |
1983 | unsigned long long start_sector; | |
1984 | string = dm_shift_arg(&as), opt_params--; | |
1985 | if (sscanf(string, "%llu%c", &start_sector, &dummy) != 1) | |
1986 | goto invalid_optional; | |
1987 | wc->start_sector = start_sector; | |
1988 | if (wc->start_sector != start_sector || | |
1989 | wc->start_sector >= wc->memory_map_size >> SECTOR_SHIFT) | |
1990 | goto invalid_optional; | |
1991 | } else if (!strcasecmp(string, "high_watermark") && opt_params >= 1) { | |
48debafe MP |
1992 | string = dm_shift_arg(&as), opt_params--; |
1993 | if (sscanf(string, "%d%c", &high_wm_percent, &dummy) != 1) | |
1994 | goto invalid_optional; | |
1995 | if (high_wm_percent < 0 || high_wm_percent > 100) | |
1996 | goto invalid_optional; | |
1997 | wc->high_wm_percent_set = true; | |
1998 | } else if (!strcasecmp(string, "low_watermark") && opt_params >= 1) { | |
1999 | string = dm_shift_arg(&as), opt_params--; | |
2000 | if (sscanf(string, "%d%c", &low_wm_percent, &dummy) != 1) | |
2001 | goto invalid_optional; | |
2002 | if (low_wm_percent < 0 || low_wm_percent > 100) | |
2003 | goto invalid_optional; | |
2004 | wc->low_wm_percent_set = true; | |
2005 | } else if (!strcasecmp(string, "writeback_jobs") && opt_params >= 1) { | |
2006 | string = dm_shift_arg(&as), opt_params--; | |
2007 | if (sscanf(string, "%u%c", &wc->max_writeback_jobs, &dummy) != 1) | |
2008 | goto invalid_optional; | |
2009 | wc->max_writeback_jobs_set = true; | |
2010 | } else if (!strcasecmp(string, "autocommit_blocks") && opt_params >= 1) { | |
2011 | string = dm_shift_arg(&as), opt_params--; | |
2012 | if (sscanf(string, "%u%c", &wc->autocommit_blocks, &dummy) != 1) | |
2013 | goto invalid_optional; | |
2014 | wc->autocommit_blocks_set = true; | |
2015 | } else if (!strcasecmp(string, "autocommit_time") && opt_params >= 1) { | |
2016 | unsigned autocommit_msecs; | |
2017 | string = dm_shift_arg(&as), opt_params--; | |
2018 | if (sscanf(string, "%u%c", &autocommit_msecs, &dummy) != 1) | |
2019 | goto invalid_optional; | |
2020 | if (autocommit_msecs > 3600000) | |
2021 | goto invalid_optional; | |
2022 | wc->autocommit_jiffies = msecs_to_jiffies(autocommit_msecs); | |
2023 | wc->autocommit_time_set = true; | |
2024 | } else if (!strcasecmp(string, "fua")) { | |
2025 | if (WC_MODE_PMEM(wc)) { | |
2026 | wc->writeback_fua = true; | |
2027 | wc->writeback_fua_set = true; | |
2028 | } else goto invalid_optional; | |
2029 | } else if (!strcasecmp(string, "nofua")) { | |
2030 | if (WC_MODE_PMEM(wc)) { | |
2031 | wc->writeback_fua = false; | |
2032 | wc->writeback_fua_set = true; | |
2033 | } else goto invalid_optional; | |
2034 | } else { | |
2035 | invalid_optional: | |
2036 | r = -EINVAL; | |
2037 | ti->error = "Invalid optional argument"; | |
2038 | goto bad; | |
2039 | } | |
2040 | } | |
2041 | ||
2042 | if (high_wm_percent < low_wm_percent) { | |
2043 | r = -EINVAL; | |
2044 | ti->error = "High watermark must be greater than or equal to low watermark"; | |
2045 | goto bad; | |
2046 | } | |
2047 | ||
d284f824 MP |
2048 | if (WC_MODE_PMEM(wc)) { |
2049 | r = persistent_memory_claim(wc); | |
2050 | if (r) { | |
2051 | ti->error = "Unable to map persistent memory for cache"; | |
2052 | goto bad; | |
2053 | } | |
2054 | } else { | |
48debafe MP |
2055 | struct dm_io_region region; |
2056 | struct dm_io_request req; | |
2057 | size_t n_blocks, n_metadata_blocks; | |
2058 | uint64_t n_bitmap_bits; | |
2059 | ||
d284f824 MP |
2060 | wc->memory_map_size -= (uint64_t)wc->start_sector << SECTOR_SHIFT; |
2061 | ||
48debafe MP |
2062 | bio_list_init(&wc->flush_list); |
2063 | wc->flush_thread = kthread_create(writecache_flush_thread, wc, "dm_writecache_flush"); | |
2064 | if (IS_ERR(wc->flush_thread)) { | |
2065 | r = PTR_ERR(wc->flush_thread); | |
2066 | wc->flush_thread = NULL; | |
2067 | ti->error = "Couldn't spawn endio thread"; | |
2068 | goto bad; | |
2069 | } | |
2070 | wake_up_process(wc->flush_thread); | |
2071 | ||
2072 | r = calculate_memory_size(wc->memory_map_size, wc->block_size, | |
2073 | &n_blocks, &n_metadata_blocks); | |
2074 | if (r) { | |
2075 | ti->error = "Invalid device size"; | |
2076 | goto bad; | |
2077 | } | |
2078 | ||
2079 | n_bitmap_bits = (((uint64_t)n_metadata_blocks << wc->block_size_bits) + | |
2080 | BITMAP_GRANULARITY - 1) / BITMAP_GRANULARITY; | |
2081 | /* this is limitation of test_bit functions */ | |
2082 | if (n_bitmap_bits > 1U << 31) { | |
2083 | r = -EFBIG; | |
2084 | ti->error = "Invalid device size"; | |
2085 | goto bad; | |
2086 | } | |
2087 | ||
2088 | wc->memory_map = vmalloc(n_metadata_blocks << wc->block_size_bits); | |
2089 | if (!wc->memory_map) { | |
2090 | r = -ENOMEM; | |
2091 | ti->error = "Unable to allocate memory for metadata"; | |
2092 | goto bad; | |
2093 | } | |
2094 | ||
2095 | wc->dm_kcopyd = dm_kcopyd_client_create(&dm_kcopyd_throttle); | |
2096 | if (IS_ERR(wc->dm_kcopyd)) { | |
2097 | r = PTR_ERR(wc->dm_kcopyd); | |
2098 | ti->error = "Unable to allocate dm-kcopyd client"; | |
2099 | wc->dm_kcopyd = NULL; | |
2100 | goto bad; | |
2101 | } | |
2102 | ||
2103 | wc->metadata_sectors = n_metadata_blocks << (wc->block_size_bits - SECTOR_SHIFT); | |
2104 | wc->dirty_bitmap_size = (n_bitmap_bits + BITS_PER_LONG - 1) / | |
2105 | BITS_PER_LONG * sizeof(unsigned long); | |
2106 | wc->dirty_bitmap = vzalloc(wc->dirty_bitmap_size); | |
2107 | if (!wc->dirty_bitmap) { | |
2108 | r = -ENOMEM; | |
2109 | ti->error = "Unable to allocate dirty bitmap"; | |
2110 | goto bad; | |
2111 | } | |
2112 | ||
2113 | region.bdev = wc->ssd_dev->bdev; | |
d284f824 | 2114 | region.sector = wc->start_sector; |
48debafe MP |
2115 | region.count = wc->metadata_sectors; |
2116 | req.bi_op = REQ_OP_READ; | |
2117 | req.bi_op_flags = REQ_SYNC; | |
2118 | req.mem.type = DM_IO_VMA; | |
2119 | req.mem.ptr.vma = (char *)wc->memory_map; | |
2120 | req.client = wc->dm_io; | |
2121 | req.notify.fn = NULL; | |
2122 | ||
2123 | r = dm_io(&req, 1, ®ion, NULL); | |
2124 | if (r) { | |
2125 | ti->error = "Unable to read metadata"; | |
2126 | goto bad; | |
2127 | } | |
2128 | } | |
2129 | ||
2130 | r = memcpy_mcsafe(&s, sb(wc), sizeof(struct wc_memory_superblock)); | |
2131 | if (r) { | |
2132 | ti->error = "Hardware memory error when reading superblock"; | |
2133 | goto bad; | |
2134 | } | |
2135 | if (!le32_to_cpu(s.magic) && !le32_to_cpu(s.version)) { | |
2136 | r = init_memory(wc); | |
2137 | if (r) { | |
2138 | ti->error = "Unable to initialize device"; | |
2139 | goto bad; | |
2140 | } | |
2141 | r = memcpy_mcsafe(&s, sb(wc), sizeof(struct wc_memory_superblock)); | |
2142 | if (r) { | |
2143 | ti->error = "Hardware memory error when reading superblock"; | |
2144 | goto bad; | |
2145 | } | |
2146 | } | |
2147 | ||
2148 | if (le32_to_cpu(s.magic) != MEMORY_SUPERBLOCK_MAGIC) { | |
2149 | ti->error = "Invalid magic in the superblock"; | |
2150 | r = -EINVAL; | |
2151 | goto bad; | |
2152 | } | |
2153 | ||
2154 | if (le32_to_cpu(s.version) != MEMORY_SUPERBLOCK_VERSION) { | |
2155 | ti->error = "Invalid version in the superblock"; | |
2156 | r = -EINVAL; | |
2157 | goto bad; | |
2158 | } | |
2159 | ||
2160 | if (le32_to_cpu(s.block_size) != wc->block_size) { | |
2161 | ti->error = "Block size does not match superblock"; | |
2162 | r = -EINVAL; | |
2163 | goto bad; | |
2164 | } | |
2165 | ||
2166 | wc->n_blocks = le64_to_cpu(s.n_blocks); | |
2167 | ||
2168 | offset = wc->n_blocks * sizeof(struct wc_memory_entry); | |
2169 | if (offset / sizeof(struct wc_memory_entry) != le64_to_cpu(sb(wc)->n_blocks)) { | |
2170 | overflow: | |
2171 | ti->error = "Overflow in size calculation"; | |
2172 | r = -EINVAL; | |
2173 | goto bad; | |
2174 | } | |
2175 | offset += sizeof(struct wc_memory_superblock); | |
2176 | if (offset < sizeof(struct wc_memory_superblock)) | |
2177 | goto overflow; | |
2178 | offset = (offset + wc->block_size - 1) & ~(size_t)(wc->block_size - 1); | |
2179 | data_size = wc->n_blocks * (size_t)wc->block_size; | |
2180 | if (!offset || (data_size / wc->block_size != wc->n_blocks) || | |
2181 | (offset + data_size < offset)) | |
2182 | goto overflow; | |
2183 | if (offset + data_size > wc->memory_map_size) { | |
2184 | ti->error = "Memory area is too small"; | |
2185 | r = -EINVAL; | |
2186 | goto bad; | |
2187 | } | |
2188 | ||
2189 | wc->metadata_sectors = offset >> SECTOR_SHIFT; | |
2190 | wc->block_start = (char *)sb(wc) + offset; | |
2191 | ||
2192 | x = (uint64_t)wc->n_blocks * (100 - high_wm_percent); | |
2193 | x += 50; | |
2194 | do_div(x, 100); | |
2195 | wc->freelist_high_watermark = x; | |
2196 | x = (uint64_t)wc->n_blocks * (100 - low_wm_percent); | |
2197 | x += 50; | |
2198 | do_div(x, 100); | |
2199 | wc->freelist_low_watermark = x; | |
2200 | ||
2201 | r = writecache_alloc_entries(wc); | |
2202 | if (r) { | |
2203 | ti->error = "Cannot allocate memory"; | |
2204 | goto bad; | |
2205 | } | |
2206 | ||
2207 | ti->num_flush_bios = 1; | |
2208 | ti->flush_supported = true; | |
2209 | ti->num_discard_bios = 1; | |
2210 | ||
2211 | if (WC_MODE_PMEM(wc)) | |
2212 | persistent_memory_flush_cache(wc->memory_map, wc->memory_map_size); | |
2213 | ||
2214 | return 0; | |
2215 | ||
2216 | bad_arguments: | |
2217 | r = -EINVAL; | |
2218 | ti->error = "Bad arguments"; | |
2219 | bad: | |
2220 | writecache_dtr(ti); | |
2221 | return r; | |
2222 | } | |
2223 | ||
2224 | static void writecache_status(struct dm_target *ti, status_type_t type, | |
2225 | unsigned status_flags, char *result, unsigned maxlen) | |
2226 | { | |
2227 | struct dm_writecache *wc = ti->private; | |
2228 | unsigned extra_args; | |
2229 | unsigned sz = 0; | |
2230 | uint64_t x; | |
2231 | ||
2232 | switch (type) { | |
2233 | case STATUSTYPE_INFO: | |
2234 | DMEMIT("%ld %llu %llu %llu", writecache_has_error(wc), | |
2235 | (unsigned long long)wc->n_blocks, (unsigned long long)wc->freelist_size, | |
2236 | (unsigned long long)wc->writeback_size); | |
2237 | break; | |
2238 | case STATUSTYPE_TABLE: | |
2239 | DMEMIT("%c %s %s %u ", WC_MODE_PMEM(wc) ? 'p' : 's', | |
2240 | wc->dev->name, wc->ssd_dev->name, wc->block_size); | |
2241 | extra_args = 0; | |
9ff07e7d MP |
2242 | if (wc->start_sector) |
2243 | extra_args += 2; | |
48debafe MP |
2244 | if (wc->high_wm_percent_set) |
2245 | extra_args += 2; | |
2246 | if (wc->low_wm_percent_set) | |
2247 | extra_args += 2; | |
2248 | if (wc->max_writeback_jobs_set) | |
2249 | extra_args += 2; | |
2250 | if (wc->autocommit_blocks_set) | |
2251 | extra_args += 2; | |
2252 | if (wc->autocommit_time_set) | |
2253 | extra_args += 2; | |
2254 | if (wc->writeback_fua_set) | |
2255 | extra_args++; | |
2256 | ||
2257 | DMEMIT("%u", extra_args); | |
9ff07e7d MP |
2258 | if (wc->start_sector) |
2259 | DMEMIT(" start_sector %llu", (unsigned long long)wc->start_sector); | |
48debafe MP |
2260 | if (wc->high_wm_percent_set) { |
2261 | x = (uint64_t)wc->freelist_high_watermark * 100; | |
2262 | x += wc->n_blocks / 2; | |
2263 | do_div(x, (size_t)wc->n_blocks); | |
2264 | DMEMIT(" high_watermark %u", 100 - (unsigned)x); | |
2265 | } | |
2266 | if (wc->low_wm_percent_set) { | |
2267 | x = (uint64_t)wc->freelist_low_watermark * 100; | |
2268 | x += wc->n_blocks / 2; | |
2269 | do_div(x, (size_t)wc->n_blocks); | |
2270 | DMEMIT(" low_watermark %u", 100 - (unsigned)x); | |
2271 | } | |
2272 | if (wc->max_writeback_jobs_set) | |
2273 | DMEMIT(" writeback_jobs %u", wc->max_writeback_jobs); | |
2274 | if (wc->autocommit_blocks_set) | |
2275 | DMEMIT(" autocommit_blocks %u", wc->autocommit_blocks); | |
2276 | if (wc->autocommit_time_set) | |
2277 | DMEMIT(" autocommit_time %u", jiffies_to_msecs(wc->autocommit_jiffies)); | |
2278 | if (wc->writeback_fua_set) | |
2279 | DMEMIT(" %sfua", wc->writeback_fua ? "" : "no"); | |
2280 | break; | |
2281 | } | |
2282 | } | |
2283 | ||
2284 | static struct target_type writecache_target = { | |
2285 | .name = "writecache", | |
9ff07e7d | 2286 | .version = {1, 1, 1}, |
48debafe MP |
2287 | .module = THIS_MODULE, |
2288 | .ctr = writecache_ctr, | |
2289 | .dtr = writecache_dtr, | |
2290 | .status = writecache_status, | |
2291 | .postsuspend = writecache_suspend, | |
2292 | .resume = writecache_resume, | |
2293 | .message = writecache_message, | |
2294 | .map = writecache_map, | |
2295 | .end_io = writecache_end_io, | |
2296 | .iterate_devices = writecache_iterate_devices, | |
2297 | .io_hints = writecache_io_hints, | |
2298 | }; | |
2299 | ||
2300 | static int __init dm_writecache_init(void) | |
2301 | { | |
2302 | int r; | |
2303 | ||
2304 | r = dm_register_target(&writecache_target); | |
2305 | if (r < 0) { | |
2306 | DMERR("register failed %d", r); | |
2307 | return r; | |
2308 | } | |
2309 | ||
2310 | return 0; | |
2311 | } | |
2312 | ||
2313 | static void __exit dm_writecache_exit(void) | |
2314 | { | |
2315 | dm_unregister_target(&writecache_target); | |
2316 | } | |
2317 | ||
2318 | module_init(dm_writecache_init); | |
2319 | module_exit(dm_writecache_exit); | |
2320 | ||
2321 | MODULE_DESCRIPTION(DM_NAME " writecache target"); | |
2322 | MODULE_AUTHOR("Mikulas Patocka <dm-devel@redhat.com>"); | |
2323 | MODULE_LICENSE("GPL"); |