pmem.c 20 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770771772773774775776777778779780781782783784785786787788789
  1. // SPDX-License-Identifier: GPL-2.0-only
  2. /*
  3. * Persistent Memory Driver
  4. *
  5. * Copyright (c) 2014-2015, Intel Corporation.
  6. * Copyright (c) 2015, Christoph Hellwig <[email protected]>.
  7. * Copyright (c) 2015, Boaz Harrosh <[email protected]>.
  8. */
  9. #include <linux/blkdev.h>
  10. #include <linux/pagemap.h>
  11. #include <linux/hdreg.h>
  12. #include <linux/init.h>
  13. #include <linux/platform_device.h>
  14. #include <linux/set_memory.h>
  15. #include <linux/module.h>
  16. #include <linux/moduleparam.h>
  17. #include <linux/badblocks.h>
  18. #include <linux/memremap.h>
  19. #include <linux/vmalloc.h>
  20. #include <linux/blk-mq.h>
  21. #include <linux/pfn_t.h>
  22. #include <linux/slab.h>
  23. #include <linux/uio.h>
  24. #include <linux/dax.h>
  25. #include <linux/nd.h>
  26. #include <linux/mm.h>
  27. #include <asm/cacheflush.h>
  28. #include "pmem.h"
  29. #include "btt.h"
  30. #include "pfn.h"
  31. #include "nd.h"
  32. static struct device *to_dev(struct pmem_device *pmem)
  33. {
  34. /*
  35. * nvdimm bus services need a 'dev' parameter, and we record the device
  36. * at init in bb.dev.
  37. */
  38. return pmem->bb.dev;
  39. }
  40. static struct nd_region *to_region(struct pmem_device *pmem)
  41. {
  42. return to_nd_region(to_dev(pmem)->parent);
  43. }
  44. static phys_addr_t pmem_to_phys(struct pmem_device *pmem, phys_addr_t offset)
  45. {
  46. return pmem->phys_addr + offset;
  47. }
  48. static sector_t to_sect(struct pmem_device *pmem, phys_addr_t offset)
  49. {
  50. return (offset - pmem->data_offset) >> SECTOR_SHIFT;
  51. }
  52. static phys_addr_t to_offset(struct pmem_device *pmem, sector_t sector)
  53. {
  54. return (sector << SECTOR_SHIFT) + pmem->data_offset;
  55. }
  56. static void pmem_mkpage_present(struct pmem_device *pmem, phys_addr_t offset,
  57. unsigned int len)
  58. {
  59. phys_addr_t phys = pmem_to_phys(pmem, offset);
  60. unsigned long pfn_start, pfn_end, pfn;
  61. /* only pmem in the linear map supports HWPoison */
  62. if (is_vmalloc_addr(pmem->virt_addr))
  63. return;
  64. pfn_start = PHYS_PFN(phys);
  65. pfn_end = pfn_start + PHYS_PFN(len);
  66. for (pfn = pfn_start; pfn < pfn_end; pfn++) {
  67. struct page *page = pfn_to_page(pfn);
  68. /*
  69. * Note, no need to hold a get_dev_pagemap() reference
  70. * here since we're in the driver I/O path and
  71. * outstanding I/O requests pin the dev_pagemap.
  72. */
  73. if (test_and_clear_pmem_poison(page))
  74. clear_mce_nospec(pfn);
  75. }
  76. }
  77. static void pmem_clear_bb(struct pmem_device *pmem, sector_t sector, long blks)
  78. {
  79. if (blks == 0)
  80. return;
  81. badblocks_clear(&pmem->bb, sector, blks);
  82. if (pmem->bb_state)
  83. sysfs_notify_dirent(pmem->bb_state);
  84. }
  85. static long __pmem_clear_poison(struct pmem_device *pmem,
  86. phys_addr_t offset, unsigned int len)
  87. {
  88. phys_addr_t phys = pmem_to_phys(pmem, offset);
  89. long cleared = nvdimm_clear_poison(to_dev(pmem), phys, len);
  90. if (cleared > 0) {
  91. pmem_mkpage_present(pmem, offset, cleared);
  92. arch_invalidate_pmem(pmem->virt_addr + offset, len);
  93. }
  94. return cleared;
  95. }
  96. static blk_status_t pmem_clear_poison(struct pmem_device *pmem,
  97. phys_addr_t offset, unsigned int len)
  98. {
  99. long cleared = __pmem_clear_poison(pmem, offset, len);
  100. if (cleared < 0)
  101. return BLK_STS_IOERR;
  102. pmem_clear_bb(pmem, to_sect(pmem, offset), cleared >> SECTOR_SHIFT);
  103. if (cleared < len)
  104. return BLK_STS_IOERR;
  105. return BLK_STS_OK;
  106. }
  107. static void write_pmem(void *pmem_addr, struct page *page,
  108. unsigned int off, unsigned int len)
  109. {
  110. unsigned int chunk;
  111. void *mem;
  112. while (len) {
  113. mem = kmap_atomic(page);
  114. chunk = min_t(unsigned int, len, PAGE_SIZE - off);
  115. memcpy_flushcache(pmem_addr, mem + off, chunk);
  116. kunmap_atomic(mem);
  117. len -= chunk;
  118. off = 0;
  119. page++;
  120. pmem_addr += chunk;
  121. }
  122. }
  123. static blk_status_t read_pmem(struct page *page, unsigned int off,
  124. void *pmem_addr, unsigned int len)
  125. {
  126. unsigned int chunk;
  127. unsigned long rem;
  128. void *mem;
  129. while (len) {
  130. mem = kmap_atomic(page);
  131. chunk = min_t(unsigned int, len, PAGE_SIZE - off);
  132. rem = copy_mc_to_kernel(mem + off, pmem_addr, chunk);
  133. kunmap_atomic(mem);
  134. if (rem)
  135. return BLK_STS_IOERR;
  136. len -= chunk;
  137. off = 0;
  138. page++;
  139. pmem_addr += chunk;
  140. }
  141. return BLK_STS_OK;
  142. }
  143. static blk_status_t pmem_do_read(struct pmem_device *pmem,
  144. struct page *page, unsigned int page_off,
  145. sector_t sector, unsigned int len)
  146. {
  147. blk_status_t rc;
  148. phys_addr_t pmem_off = to_offset(pmem, sector);
  149. void *pmem_addr = pmem->virt_addr + pmem_off;
  150. if (unlikely(is_bad_pmem(&pmem->bb, sector, len)))
  151. return BLK_STS_IOERR;
  152. rc = read_pmem(page, page_off, pmem_addr, len);
  153. flush_dcache_page(page);
  154. return rc;
  155. }
  156. static blk_status_t pmem_do_write(struct pmem_device *pmem,
  157. struct page *page, unsigned int page_off,
  158. sector_t sector, unsigned int len)
  159. {
  160. phys_addr_t pmem_off = to_offset(pmem, sector);
  161. void *pmem_addr = pmem->virt_addr + pmem_off;
  162. if (unlikely(is_bad_pmem(&pmem->bb, sector, len))) {
  163. blk_status_t rc = pmem_clear_poison(pmem, pmem_off, len);
  164. if (rc != BLK_STS_OK)
  165. return rc;
  166. }
  167. flush_dcache_page(page);
  168. write_pmem(pmem_addr, page, page_off, len);
  169. return BLK_STS_OK;
  170. }
  171. static void pmem_submit_bio(struct bio *bio)
  172. {
  173. int ret = 0;
  174. blk_status_t rc = 0;
  175. bool do_acct;
  176. unsigned long start;
  177. struct bio_vec bvec;
  178. struct bvec_iter iter;
  179. struct pmem_device *pmem = bio->bi_bdev->bd_disk->private_data;
  180. struct nd_region *nd_region = to_region(pmem);
  181. if (bio->bi_opf & REQ_PREFLUSH)
  182. ret = nvdimm_flush(nd_region, bio);
  183. do_acct = blk_queue_io_stat(bio->bi_bdev->bd_disk->queue);
  184. if (do_acct)
  185. start = bio_start_io_acct(bio);
  186. bio_for_each_segment(bvec, bio, iter) {
  187. if (op_is_write(bio_op(bio)))
  188. rc = pmem_do_write(pmem, bvec.bv_page, bvec.bv_offset,
  189. iter.bi_sector, bvec.bv_len);
  190. else
  191. rc = pmem_do_read(pmem, bvec.bv_page, bvec.bv_offset,
  192. iter.bi_sector, bvec.bv_len);
  193. if (rc) {
  194. bio->bi_status = rc;
  195. break;
  196. }
  197. }
  198. if (do_acct)
  199. bio_end_io_acct(bio, start);
  200. if (bio->bi_opf & REQ_FUA)
  201. ret = nvdimm_flush(nd_region, bio);
  202. if (ret)
  203. bio->bi_status = errno_to_blk_status(ret);
  204. bio_endio(bio);
  205. }
  206. static int pmem_rw_page(struct block_device *bdev, sector_t sector,
  207. struct page *page, enum req_op op)
  208. {
  209. struct pmem_device *pmem = bdev->bd_disk->private_data;
  210. blk_status_t rc;
  211. if (op_is_write(op))
  212. rc = pmem_do_write(pmem, page, 0, sector, thp_size(page));
  213. else
  214. rc = pmem_do_read(pmem, page, 0, sector, thp_size(page));
  215. /*
  216. * The ->rw_page interface is subtle and tricky. The core
  217. * retries on any error, so we can only invoke page_endio() in
  218. * the successful completion case. Otherwise, we'll see crashes
  219. * caused by double completion.
  220. */
  221. if (rc == 0)
  222. page_endio(page, op_is_write(op), 0);
  223. return blk_status_to_errno(rc);
  224. }
  225. /* see "strong" declaration in tools/testing/nvdimm/pmem-dax.c */
  226. __weak long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
  227. long nr_pages, enum dax_access_mode mode, void **kaddr,
  228. pfn_t *pfn)
  229. {
  230. resource_size_t offset = PFN_PHYS(pgoff) + pmem->data_offset;
  231. sector_t sector = PFN_PHYS(pgoff) >> SECTOR_SHIFT;
  232. unsigned int num = PFN_PHYS(nr_pages) >> SECTOR_SHIFT;
  233. struct badblocks *bb = &pmem->bb;
  234. sector_t first_bad;
  235. int num_bad;
  236. if (kaddr)
  237. *kaddr = pmem->virt_addr + offset;
  238. if (pfn)
  239. *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
  240. if (bb->count &&
  241. badblocks_check(bb, sector, num, &first_bad, &num_bad)) {
  242. long actual_nr;
  243. if (mode != DAX_RECOVERY_WRITE)
  244. return -EIO;
  245. /*
  246. * Set the recovery stride is set to kernel page size because
  247. * the underlying driver and firmware clear poison functions
  248. * don't appear to handle large chunk(such as 2MiB) reliably.
  249. */
  250. actual_nr = PHYS_PFN(
  251. PAGE_ALIGN((first_bad - sector) << SECTOR_SHIFT));
  252. dev_dbg(pmem->bb.dev, "start sector(%llu), nr_pages(%ld), first_bad(%llu), actual_nr(%ld)\n",
  253. sector, nr_pages, first_bad, actual_nr);
  254. if (actual_nr)
  255. return actual_nr;
  256. return 1;
  257. }
  258. /*
  259. * If badblocks are present but not in the range, limit known good range
  260. * to the requested range.
  261. */
  262. if (bb->count)
  263. return nr_pages;
  264. return PHYS_PFN(pmem->size - pmem->pfn_pad - offset);
  265. }
  266. static const struct block_device_operations pmem_fops = {
  267. .owner = THIS_MODULE,
  268. .submit_bio = pmem_submit_bio,
  269. .rw_page = pmem_rw_page,
  270. };
  271. static int pmem_dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
  272. size_t nr_pages)
  273. {
  274. struct pmem_device *pmem = dax_get_private(dax_dev);
  275. return blk_status_to_errno(pmem_do_write(pmem, ZERO_PAGE(0), 0,
  276. PFN_PHYS(pgoff) >> SECTOR_SHIFT,
  277. PAGE_SIZE));
  278. }
  279. static long pmem_dax_direct_access(struct dax_device *dax_dev,
  280. pgoff_t pgoff, long nr_pages, enum dax_access_mode mode,
  281. void **kaddr, pfn_t *pfn)
  282. {
  283. struct pmem_device *pmem = dax_get_private(dax_dev);
  284. return __pmem_direct_access(pmem, pgoff, nr_pages, mode, kaddr, pfn);
  285. }
  286. /*
  287. * The recovery write thread started out as a normal pwrite thread and
  288. * when the filesystem was told about potential media error in the
  289. * range, filesystem turns the normal pwrite to a dax_recovery_write.
  290. *
  291. * The recovery write consists of clearing media poison, clearing page
  292. * HWPoison bit, reenable page-wide read-write permission, flush the
  293. * caches and finally write. A competing pread thread will be held
  294. * off during the recovery process since data read back might not be
  295. * valid, and this is achieved by clearing the badblock records after
  296. * the recovery write is complete. Competing recovery write threads
  297. * are already serialized by writer lock held by dax_iomap_rw().
  298. */
  299. static size_t pmem_recovery_write(struct dax_device *dax_dev, pgoff_t pgoff,
  300. void *addr, size_t bytes, struct iov_iter *i)
  301. {
  302. struct pmem_device *pmem = dax_get_private(dax_dev);
  303. size_t olen, len, off;
  304. phys_addr_t pmem_off;
  305. struct device *dev = pmem->bb.dev;
  306. long cleared;
  307. off = offset_in_page(addr);
  308. len = PFN_PHYS(PFN_UP(off + bytes));
  309. if (!is_bad_pmem(&pmem->bb, PFN_PHYS(pgoff) >> SECTOR_SHIFT, len))
  310. return _copy_from_iter_flushcache(addr, bytes, i);
  311. /*
  312. * Not page-aligned range cannot be recovered. This should not
  313. * happen unless something else went wrong.
  314. */
  315. if (off || !PAGE_ALIGNED(bytes)) {
  316. dev_dbg(dev, "Found poison, but addr(%p) or bytes(%#zx) not page aligned\n",
  317. addr, bytes);
  318. return 0;
  319. }
  320. pmem_off = PFN_PHYS(pgoff) + pmem->data_offset;
  321. cleared = __pmem_clear_poison(pmem, pmem_off, len);
  322. if (cleared > 0 && cleared < len) {
  323. dev_dbg(dev, "poison cleared only %ld out of %zu bytes\n",
  324. cleared, len);
  325. return 0;
  326. }
  327. if (cleared < 0) {
  328. dev_dbg(dev, "poison clear failed: %ld\n", cleared);
  329. return 0;
  330. }
  331. olen = _copy_from_iter_flushcache(addr, bytes, i);
  332. pmem_clear_bb(pmem, to_sect(pmem, pmem_off), cleared >> SECTOR_SHIFT);
  333. return olen;
  334. }
  335. static const struct dax_operations pmem_dax_ops = {
  336. .direct_access = pmem_dax_direct_access,
  337. .zero_page_range = pmem_dax_zero_page_range,
  338. .recovery_write = pmem_recovery_write,
  339. };
  340. static ssize_t write_cache_show(struct device *dev,
  341. struct device_attribute *attr, char *buf)
  342. {
  343. struct pmem_device *pmem = dev_to_disk(dev)->private_data;
  344. return sprintf(buf, "%d\n", !!dax_write_cache_enabled(pmem->dax_dev));
  345. }
  346. static ssize_t write_cache_store(struct device *dev,
  347. struct device_attribute *attr, const char *buf, size_t len)
  348. {
  349. struct pmem_device *pmem = dev_to_disk(dev)->private_data;
  350. bool write_cache;
  351. int rc;
  352. rc = strtobool(buf, &write_cache);
  353. if (rc)
  354. return rc;
  355. dax_write_cache(pmem->dax_dev, write_cache);
  356. return len;
  357. }
  358. static DEVICE_ATTR_RW(write_cache);
  359. static umode_t dax_visible(struct kobject *kobj, struct attribute *a, int n)
  360. {
  361. #ifndef CONFIG_ARCH_HAS_PMEM_API
  362. if (a == &dev_attr_write_cache.attr)
  363. return 0;
  364. #endif
  365. return a->mode;
  366. }
  367. static struct attribute *dax_attributes[] = {
  368. &dev_attr_write_cache.attr,
  369. NULL,
  370. };
  371. static const struct attribute_group dax_attribute_group = {
  372. .name = "dax",
  373. .attrs = dax_attributes,
  374. .is_visible = dax_visible,
  375. };
  376. static const struct attribute_group *pmem_attribute_groups[] = {
  377. &dax_attribute_group,
  378. NULL,
  379. };
  380. static void pmem_release_disk(void *__pmem)
  381. {
  382. struct pmem_device *pmem = __pmem;
  383. dax_remove_host(pmem->disk);
  384. kill_dax(pmem->dax_dev);
  385. put_dax(pmem->dax_dev);
  386. del_gendisk(pmem->disk);
  387. put_disk(pmem->disk);
  388. }
  389. static int pmem_pagemap_memory_failure(struct dev_pagemap *pgmap,
  390. unsigned long pfn, unsigned long nr_pages, int mf_flags)
  391. {
  392. struct pmem_device *pmem =
  393. container_of(pgmap, struct pmem_device, pgmap);
  394. u64 offset = PFN_PHYS(pfn) - pmem->phys_addr - pmem->data_offset;
  395. u64 len = nr_pages << PAGE_SHIFT;
  396. return dax_holder_notify_failure(pmem->dax_dev, offset, len, mf_flags);
  397. }
  398. static const struct dev_pagemap_ops fsdax_pagemap_ops = {
  399. .memory_failure = pmem_pagemap_memory_failure,
  400. };
  401. static int pmem_attach_disk(struct device *dev,
  402. struct nd_namespace_common *ndns)
  403. {
  404. struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
  405. struct nd_region *nd_region = to_nd_region(dev->parent);
  406. int nid = dev_to_node(dev), fua;
  407. struct resource *res = &nsio->res;
  408. struct range bb_range;
  409. struct nd_pfn *nd_pfn = NULL;
  410. struct dax_device *dax_dev;
  411. struct nd_pfn_sb *pfn_sb;
  412. struct pmem_device *pmem;
  413. struct request_queue *q;
  414. struct gendisk *disk;
  415. void *addr;
  416. int rc;
  417. pmem = devm_kzalloc(dev, sizeof(*pmem), GFP_KERNEL);
  418. if (!pmem)
  419. return -ENOMEM;
  420. rc = devm_namespace_enable(dev, ndns, nd_info_block_reserve());
  421. if (rc)
  422. return rc;
  423. /* while nsio_rw_bytes is active, parse a pfn info block if present */
  424. if (is_nd_pfn(dev)) {
  425. nd_pfn = to_nd_pfn(dev);
  426. rc = nvdimm_setup_pfn(nd_pfn, &pmem->pgmap);
  427. if (rc)
  428. return rc;
  429. }
  430. /* we're attaching a block device, disable raw namespace access */
  431. devm_namespace_disable(dev, ndns);
  432. dev_set_drvdata(dev, pmem);
  433. pmem->phys_addr = res->start;
  434. pmem->size = resource_size(res);
  435. fua = nvdimm_has_flush(nd_region);
  436. if (!IS_ENABLED(CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE) || fua < 0) {
  437. dev_warn(dev, "unable to guarantee persistence of writes\n");
  438. fua = 0;
  439. }
  440. if (!devm_request_mem_region(dev, res->start, resource_size(res),
  441. dev_name(&ndns->dev))) {
  442. dev_warn(dev, "could not reserve region %pR\n", res);
  443. return -EBUSY;
  444. }
  445. disk = blk_alloc_disk(nid);
  446. if (!disk)
  447. return -ENOMEM;
  448. q = disk->queue;
  449. pmem->disk = disk;
  450. pmem->pgmap.owner = pmem;
  451. pmem->pfn_flags = PFN_DEV;
  452. if (is_nd_pfn(dev)) {
  453. pmem->pgmap.type = MEMORY_DEVICE_FS_DAX;
  454. pmem->pgmap.ops = &fsdax_pagemap_ops;
  455. addr = devm_memremap_pages(dev, &pmem->pgmap);
  456. pfn_sb = nd_pfn->pfn_sb;
  457. pmem->data_offset = le64_to_cpu(pfn_sb->dataoff);
  458. pmem->pfn_pad = resource_size(res) -
  459. range_len(&pmem->pgmap.range);
  460. pmem->pfn_flags |= PFN_MAP;
  461. bb_range = pmem->pgmap.range;
  462. bb_range.start += pmem->data_offset;
  463. } else if (pmem_should_map_pages(dev)) {
  464. pmem->pgmap.range.start = res->start;
  465. pmem->pgmap.range.end = res->end;
  466. pmem->pgmap.nr_range = 1;
  467. pmem->pgmap.type = MEMORY_DEVICE_FS_DAX;
  468. pmem->pgmap.ops = &fsdax_pagemap_ops;
  469. addr = devm_memremap_pages(dev, &pmem->pgmap);
  470. pmem->pfn_flags |= PFN_MAP;
  471. bb_range = pmem->pgmap.range;
  472. } else {
  473. addr = devm_memremap(dev, pmem->phys_addr,
  474. pmem->size, ARCH_MEMREMAP_PMEM);
  475. bb_range.start = res->start;
  476. bb_range.end = res->end;
  477. }
  478. if (IS_ERR(addr)) {
  479. rc = PTR_ERR(addr);
  480. goto out;
  481. }
  482. pmem->virt_addr = addr;
  483. blk_queue_write_cache(q, true, fua);
  484. blk_queue_physical_block_size(q, PAGE_SIZE);
  485. blk_queue_logical_block_size(q, pmem_sector_size(ndns));
  486. blk_queue_max_hw_sectors(q, UINT_MAX);
  487. blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
  488. if (pmem->pfn_flags & PFN_MAP)
  489. blk_queue_flag_set(QUEUE_FLAG_DAX, q);
  490. disk->fops = &pmem_fops;
  491. disk->private_data = pmem;
  492. nvdimm_namespace_disk_name(ndns, disk->disk_name);
  493. set_capacity(disk, (pmem->size - pmem->pfn_pad - pmem->data_offset)
  494. / 512);
  495. if (devm_init_badblocks(dev, &pmem->bb))
  496. return -ENOMEM;
  497. nvdimm_badblocks_populate(nd_region, &pmem->bb, &bb_range);
  498. disk->bb = &pmem->bb;
  499. dax_dev = alloc_dax(pmem, &pmem_dax_ops);
  500. if (IS_ERR(dax_dev)) {
  501. rc = PTR_ERR(dax_dev);
  502. goto out;
  503. }
  504. set_dax_nocache(dax_dev);
  505. set_dax_nomc(dax_dev);
  506. if (is_nvdimm_sync(nd_region))
  507. set_dax_synchronous(dax_dev);
  508. rc = dax_add_host(dax_dev, disk);
  509. if (rc)
  510. goto out_cleanup_dax;
  511. dax_write_cache(dax_dev, nvdimm_has_cache(nd_region));
  512. pmem->dax_dev = dax_dev;
  513. rc = device_add_disk(dev, disk, pmem_attribute_groups);
  514. if (rc)
  515. goto out_remove_host;
  516. if (devm_add_action_or_reset(dev, pmem_release_disk, pmem))
  517. return -ENOMEM;
  518. nvdimm_check_and_set_ro(disk);
  519. pmem->bb_state = sysfs_get_dirent(disk_to_dev(disk)->kobj.sd,
  520. "badblocks");
  521. if (!pmem->bb_state)
  522. dev_warn(dev, "'badblocks' notification disabled\n");
  523. return 0;
  524. out_remove_host:
  525. dax_remove_host(pmem->disk);
  526. out_cleanup_dax:
  527. kill_dax(pmem->dax_dev);
  528. put_dax(pmem->dax_dev);
  529. out:
  530. put_disk(pmem->disk);
  531. return rc;
  532. }
  533. static int nd_pmem_probe(struct device *dev)
  534. {
  535. int ret;
  536. struct nd_namespace_common *ndns;
  537. ndns = nvdimm_namespace_common_probe(dev);
  538. if (IS_ERR(ndns))
  539. return PTR_ERR(ndns);
  540. if (is_nd_btt(dev))
  541. return nvdimm_namespace_attach_btt(ndns);
  542. if (is_nd_pfn(dev))
  543. return pmem_attach_disk(dev, ndns);
  544. ret = devm_namespace_enable(dev, ndns, nd_info_block_reserve());
  545. if (ret)
  546. return ret;
  547. ret = nd_btt_probe(dev, ndns);
  548. if (ret == 0)
  549. return -ENXIO;
  550. /*
  551. * We have two failure conditions here, there is no
  552. * info reserver block or we found a valid info reserve block
  553. * but failed to initialize the pfn superblock.
  554. *
  555. * For the first case consider namespace as a raw pmem namespace
  556. * and attach a disk.
  557. *
  558. * For the latter, consider this a success and advance the namespace
  559. * seed.
  560. */
  561. ret = nd_pfn_probe(dev, ndns);
  562. if (ret == 0)
  563. return -ENXIO;
  564. else if (ret == -EOPNOTSUPP)
  565. return ret;
  566. ret = nd_dax_probe(dev, ndns);
  567. if (ret == 0)
  568. return -ENXIO;
  569. else if (ret == -EOPNOTSUPP)
  570. return ret;
  571. /* probe complete, attach handles namespace enabling */
  572. devm_namespace_disable(dev, ndns);
  573. return pmem_attach_disk(dev, ndns);
  574. }
  575. static void nd_pmem_remove(struct device *dev)
  576. {
  577. struct pmem_device *pmem = dev_get_drvdata(dev);
  578. if (is_nd_btt(dev))
  579. nvdimm_namespace_detach_btt(to_nd_btt(dev));
  580. else {
  581. /*
  582. * Note, this assumes device_lock() context to not
  583. * race nd_pmem_notify()
  584. */
  585. sysfs_put(pmem->bb_state);
  586. pmem->bb_state = NULL;
  587. }
  588. nvdimm_flush(to_nd_region(dev->parent), NULL);
  589. }
  590. static void nd_pmem_shutdown(struct device *dev)
  591. {
  592. nvdimm_flush(to_nd_region(dev->parent), NULL);
  593. }
  594. static void pmem_revalidate_poison(struct device *dev)
  595. {
  596. struct nd_region *nd_region;
  597. resource_size_t offset = 0, end_trunc = 0;
  598. struct nd_namespace_common *ndns;
  599. struct nd_namespace_io *nsio;
  600. struct badblocks *bb;
  601. struct range range;
  602. struct kernfs_node *bb_state;
  603. if (is_nd_btt(dev)) {
  604. struct nd_btt *nd_btt = to_nd_btt(dev);
  605. ndns = nd_btt->ndns;
  606. nd_region = to_nd_region(ndns->dev.parent);
  607. nsio = to_nd_namespace_io(&ndns->dev);
  608. bb = &nsio->bb;
  609. bb_state = NULL;
  610. } else {
  611. struct pmem_device *pmem = dev_get_drvdata(dev);
  612. nd_region = to_region(pmem);
  613. bb = &pmem->bb;
  614. bb_state = pmem->bb_state;
  615. if (is_nd_pfn(dev)) {
  616. struct nd_pfn *nd_pfn = to_nd_pfn(dev);
  617. struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
  618. ndns = nd_pfn->ndns;
  619. offset = pmem->data_offset +
  620. __le32_to_cpu(pfn_sb->start_pad);
  621. end_trunc = __le32_to_cpu(pfn_sb->end_trunc);
  622. } else {
  623. ndns = to_ndns(dev);
  624. }
  625. nsio = to_nd_namespace_io(&ndns->dev);
  626. }
  627. range.start = nsio->res.start + offset;
  628. range.end = nsio->res.end - end_trunc;
  629. nvdimm_badblocks_populate(nd_region, bb, &range);
  630. if (bb_state)
  631. sysfs_notify_dirent(bb_state);
  632. }
  633. static void pmem_revalidate_region(struct device *dev)
  634. {
  635. struct pmem_device *pmem;
  636. if (is_nd_btt(dev)) {
  637. struct nd_btt *nd_btt = to_nd_btt(dev);
  638. struct btt *btt = nd_btt->btt;
  639. nvdimm_check_and_set_ro(btt->btt_disk);
  640. return;
  641. }
  642. pmem = dev_get_drvdata(dev);
  643. nvdimm_check_and_set_ro(pmem->disk);
  644. }
  645. static void nd_pmem_notify(struct device *dev, enum nvdimm_event event)
  646. {
  647. switch (event) {
  648. case NVDIMM_REVALIDATE_POISON:
  649. pmem_revalidate_poison(dev);
  650. break;
  651. case NVDIMM_REVALIDATE_REGION:
  652. pmem_revalidate_region(dev);
  653. break;
  654. default:
  655. dev_WARN_ONCE(dev, 1, "notify: unknown event: %d\n", event);
  656. break;
  657. }
  658. }
  659. MODULE_ALIAS("pmem");
  660. MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_IO);
  661. MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_PMEM);
  662. static struct nd_device_driver nd_pmem_driver = {
  663. .probe = nd_pmem_probe,
  664. .remove = nd_pmem_remove,
  665. .notify = nd_pmem_notify,
  666. .shutdown = nd_pmem_shutdown,
  667. .drv = {
  668. .name = "nd_pmem",
  669. },
  670. .type = ND_DRIVER_NAMESPACE_IO | ND_DRIVER_NAMESPACE_PMEM,
  671. };
  672. module_nd_driver(nd_pmem_driver);
  673. MODULE_AUTHOR("Ross Zwisler <[email protected]>");
  674. MODULE_LICENSE("GPL v2");