Commit | Line | Data |
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9e853f23 RZ |
1 | /* |
2 | * Persistent Memory Driver | |
3 | * | |
9f53f9fa | 4 | * Copyright (c) 2014-2015, Intel Corporation. |
9e853f23 RZ |
5 | * Copyright (c) 2015, Christoph Hellwig <hch@lst.de>. |
6 | * Copyright (c) 2015, Boaz Harrosh <boaz@plexistor.com>. | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify it | |
9 | * under the terms and conditions of the GNU General Public License, | |
10 | * version 2, as published by the Free Software Foundation. | |
11 | * | |
12 | * This program is distributed in the hope it will be useful, but WITHOUT | |
13 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
15 | * more details. | |
16 | */ | |
17 | ||
18 | #include <asm/cacheflush.h> | |
19 | #include <linux/blkdev.h> | |
20 | #include <linux/hdreg.h> | |
21 | #include <linux/init.h> | |
22 | #include <linux/platform_device.h> | |
23 | #include <linux/module.h> | |
32ab0a3f | 24 | #include <linux/memory_hotplug.h> |
9e853f23 | 25 | #include <linux/moduleparam.h> |
32ab0a3f | 26 | #include <linux/vmalloc.h> |
9e853f23 | 27 | #include <linux/slab.h> |
61031952 | 28 | #include <linux/pmem.h> |
9f53f9fa | 29 | #include <linux/nd.h> |
32ab0a3f | 30 | #include "pfn.h" |
9f53f9fa | 31 | #include "nd.h" |
9e853f23 RZ |
32 | |
33 | struct pmem_device { | |
34 | struct request_queue *pmem_queue; | |
35 | struct gendisk *pmem_disk; | |
32ab0a3f | 36 | struct nd_namespace_common *ndns; |
9e853f23 RZ |
37 | |
38 | /* One contiguous memory region per device */ | |
39 | phys_addr_t phys_addr; | |
32ab0a3f DW |
40 | /* when non-zero this device is hosting a 'pfn' instance */ |
41 | phys_addr_t data_offset; | |
61031952 | 42 | void __pmem *virt_addr; |
9e853f23 RZ |
43 | size_t size; |
44 | }; | |
45 | ||
46 | static int pmem_major; | |
9e853f23 RZ |
47 | |
48 | static void pmem_do_bvec(struct pmem_device *pmem, struct page *page, | |
49 | unsigned int len, unsigned int off, int rw, | |
50 | sector_t sector) | |
51 | { | |
52 | void *mem = kmap_atomic(page); | |
32ab0a3f | 53 | phys_addr_t pmem_off = sector * 512 + pmem->data_offset; |
61031952 | 54 | void __pmem *pmem_addr = pmem->virt_addr + pmem_off; |
9e853f23 RZ |
55 | |
56 | if (rw == READ) { | |
61031952 | 57 | memcpy_from_pmem(mem + off, pmem_addr, len); |
9e853f23 RZ |
58 | flush_dcache_page(page); |
59 | } else { | |
60 | flush_dcache_page(page); | |
61031952 | 61 | memcpy_to_pmem(pmem_addr, mem + off, len); |
9e853f23 RZ |
62 | } |
63 | ||
64 | kunmap_atomic(mem); | |
65 | } | |
66 | ||
67 | static void pmem_make_request(struct request_queue *q, struct bio *bio) | |
68 | { | |
f0dc089c DW |
69 | bool do_acct; |
70 | unsigned long start; | |
9e853f23 | 71 | struct bio_vec bvec; |
9e853f23 | 72 | struct bvec_iter iter; |
edc870e5 DW |
73 | struct block_device *bdev = bio->bi_bdev; |
74 | struct pmem_device *pmem = bdev->bd_disk->private_data; | |
9e853f23 | 75 | |
f0dc089c | 76 | do_acct = nd_iostat_start(bio, &start); |
edc870e5 | 77 | bio_for_each_segment(bvec, bio, iter) |
9e853f23 | 78 | pmem_do_bvec(pmem, bvec.bv_page, bvec.bv_len, bvec.bv_offset, |
edc870e5 | 79 | bio_data_dir(bio), iter.bi_sector); |
f0dc089c DW |
80 | if (do_acct) |
81 | nd_iostat_end(bio, start); | |
61031952 RZ |
82 | |
83 | if (bio_data_dir(bio)) | |
84 | wmb_pmem(); | |
85 | ||
4246a0b6 | 86 | bio_endio(bio); |
9e853f23 RZ |
87 | } |
88 | ||
89 | static int pmem_rw_page(struct block_device *bdev, sector_t sector, | |
90 | struct page *page, int rw) | |
91 | { | |
92 | struct pmem_device *pmem = bdev->bd_disk->private_data; | |
93 | ||
94 | pmem_do_bvec(pmem, page, PAGE_CACHE_SIZE, 0, rw, sector); | |
ba8fe0f8 RZ |
95 | if (rw & WRITE) |
96 | wmb_pmem(); | |
9e853f23 RZ |
97 | page_endio(page, rw & WRITE, 0); |
98 | ||
99 | return 0; | |
100 | } | |
101 | ||
102 | static long pmem_direct_access(struct block_device *bdev, sector_t sector, | |
cb389b9c | 103 | void __pmem **kaddr, unsigned long *pfn) |
9e853f23 RZ |
104 | { |
105 | struct pmem_device *pmem = bdev->bd_disk->private_data; | |
32ab0a3f DW |
106 | resource_size_t offset = sector * 512 + pmem->data_offset; |
107 | resource_size_t size; | |
108 | ||
109 | if (pmem->data_offset) { | |
110 | /* | |
111 | * Limit the direct_access() size to what is covered by | |
112 | * the memmap | |
113 | */ | |
114 | size = (pmem->size - offset) & ~ND_PFN_MASK; | |
115 | } else | |
116 | size = pmem->size - offset; | |
9e853f23 | 117 | |
61031952 | 118 | /* FIXME convert DAX to comprehend that this mapping has a lifetime */ |
e2e05394 | 119 | *kaddr = pmem->virt_addr + offset; |
9e853f23 RZ |
120 | *pfn = (pmem->phys_addr + offset) >> PAGE_SHIFT; |
121 | ||
32ab0a3f | 122 | return size; |
9e853f23 RZ |
123 | } |
124 | ||
125 | static const struct block_device_operations pmem_fops = { | |
126 | .owner = THIS_MODULE, | |
127 | .rw_page = pmem_rw_page, | |
128 | .direct_access = pmem_direct_access, | |
58138820 | 129 | .revalidate_disk = nvdimm_revalidate_disk, |
9e853f23 RZ |
130 | }; |
131 | ||
9f53f9fa DW |
132 | static struct pmem_device *pmem_alloc(struct device *dev, |
133 | struct resource *res, int id) | |
9e853f23 RZ |
134 | { |
135 | struct pmem_device *pmem; | |
9e853f23 | 136 | |
708ab62b | 137 | pmem = devm_kzalloc(dev, sizeof(*pmem), GFP_KERNEL); |
9e853f23 | 138 | if (!pmem) |
8c2f7e86 | 139 | return ERR_PTR(-ENOMEM); |
9e853f23 RZ |
140 | |
141 | pmem->phys_addr = res->start; | |
142 | pmem->size = resource_size(res); | |
96601adb | 143 | if (!arch_has_wmb_pmem()) |
61031952 | 144 | dev_warn(dev, "unable to guarantee persistence of writes\n"); |
9e853f23 | 145 | |
708ab62b CH |
146 | if (!devm_request_mem_region(dev, pmem->phys_addr, pmem->size, |
147 | dev_name(dev))) { | |
9f53f9fa DW |
148 | dev_warn(dev, "could not reserve region [0x%pa:0x%zx]\n", |
149 | &pmem->phys_addr, pmem->size); | |
8c2f7e86 | 150 | return ERR_PTR(-EBUSY); |
9e853f23 RZ |
151 | } |
152 | ||
b36f4761 DW |
153 | if (pmem_should_map_pages(dev)) |
154 | pmem->virt_addr = (void __pmem *) devm_memremap_pages(dev, res); | |
155 | else | |
a639315d DW |
156 | pmem->virt_addr = (void __pmem *) devm_memremap(dev, |
157 | pmem->phys_addr, pmem->size, | |
158 | ARCH_MEMREMAP_PMEM); | |
b36f4761 DW |
159 | |
160 | if (IS_ERR(pmem->virt_addr)) | |
161 | return (void __force *) pmem->virt_addr; | |
8c2f7e86 DW |
162 | |
163 | return pmem; | |
164 | } | |
165 | ||
166 | static void pmem_detach_disk(struct pmem_device *pmem) | |
167 | { | |
32ab0a3f DW |
168 | if (!pmem->pmem_disk) |
169 | return; | |
170 | ||
8c2f7e86 DW |
171 | del_gendisk(pmem->pmem_disk); |
172 | put_disk(pmem->pmem_disk); | |
173 | blk_cleanup_queue(pmem->pmem_queue); | |
174 | } | |
175 | ||
32ab0a3f DW |
176 | static int pmem_attach_disk(struct device *dev, |
177 | struct nd_namespace_common *ndns, struct pmem_device *pmem) | |
8c2f7e86 | 178 | { |
8c2f7e86 | 179 | struct gendisk *disk; |
9e853f23 RZ |
180 | |
181 | pmem->pmem_queue = blk_alloc_queue(GFP_KERNEL); | |
182 | if (!pmem->pmem_queue) | |
8c2f7e86 | 183 | return -ENOMEM; |
9e853f23 RZ |
184 | |
185 | blk_queue_make_request(pmem->pmem_queue, pmem_make_request); | |
6b47496a | 186 | blk_queue_physical_block_size(pmem->pmem_queue, PAGE_SIZE); |
43d3fa3a | 187 | blk_queue_max_hw_sectors(pmem->pmem_queue, UINT_MAX); |
9e853f23 | 188 | blk_queue_bounce_limit(pmem->pmem_queue, BLK_BOUNCE_ANY); |
0f51c4fa | 189 | queue_flag_set_unlocked(QUEUE_FLAG_NONROT, pmem->pmem_queue); |
9e853f23 | 190 | |
9f53f9fa | 191 | disk = alloc_disk(0); |
8c2f7e86 DW |
192 | if (!disk) { |
193 | blk_cleanup_queue(pmem->pmem_queue); | |
194 | return -ENOMEM; | |
195 | } | |
9e853f23 | 196 | |
9e853f23 | 197 | disk->major = pmem_major; |
9f53f9fa | 198 | disk->first_minor = 0; |
9e853f23 RZ |
199 | disk->fops = &pmem_fops; |
200 | disk->private_data = pmem; | |
201 | disk->queue = pmem->pmem_queue; | |
202 | disk->flags = GENHD_FL_EXT_DEVT; | |
5212e11f | 203 | nvdimm_namespace_disk_name(ndns, disk->disk_name); |
32ab0a3f DW |
204 | disk->driverfs_dev = dev; |
205 | set_capacity(disk, (pmem->size - pmem->data_offset) / 512); | |
9e853f23 RZ |
206 | pmem->pmem_disk = disk; |
207 | ||
208 | add_disk(disk); | |
58138820 | 209 | revalidate_disk(disk); |
9e853f23 | 210 | |
8c2f7e86 DW |
211 | return 0; |
212 | } | |
9e853f23 | 213 | |
8c2f7e86 DW |
214 | static int pmem_rw_bytes(struct nd_namespace_common *ndns, |
215 | resource_size_t offset, void *buf, size_t size, int rw) | |
216 | { | |
217 | struct pmem_device *pmem = dev_get_drvdata(ndns->claim); | |
218 | ||
219 | if (unlikely(offset + size > pmem->size)) { | |
220 | dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n"); | |
221 | return -EFAULT; | |
222 | } | |
223 | ||
224 | if (rw == READ) | |
61031952 RZ |
225 | memcpy_from_pmem(buf, pmem->virt_addr + offset, size); |
226 | else { | |
227 | memcpy_to_pmem(pmem->virt_addr + offset, buf, size); | |
228 | wmb_pmem(); | |
229 | } | |
8c2f7e86 DW |
230 | |
231 | return 0; | |
232 | } | |
233 | ||
32ab0a3f DW |
234 | static int nd_pfn_init(struct nd_pfn *nd_pfn) |
235 | { | |
236 | struct nd_pfn_sb *pfn_sb = kzalloc(sizeof(*pfn_sb), GFP_KERNEL); | |
237 | struct pmem_device *pmem = dev_get_drvdata(&nd_pfn->dev); | |
238 | struct nd_namespace_common *ndns = nd_pfn->ndns; | |
239 | struct nd_region *nd_region; | |
240 | unsigned long npfns; | |
241 | phys_addr_t offset; | |
242 | u64 checksum; | |
243 | int rc; | |
244 | ||
245 | if (!pfn_sb) | |
246 | return -ENOMEM; | |
247 | ||
248 | nd_pfn->pfn_sb = pfn_sb; | |
249 | rc = nd_pfn_validate(nd_pfn); | |
250 | if (rc == 0 || rc == -EBUSY) | |
251 | return rc; | |
252 | ||
253 | /* section alignment for simple hotplug */ | |
254 | if (nvdimm_namespace_capacity(ndns) < ND_PFN_ALIGN | |
255 | || pmem->phys_addr & ND_PFN_MASK) | |
256 | return -ENODEV; | |
257 | ||
258 | nd_region = to_nd_region(nd_pfn->dev.parent); | |
259 | if (nd_region->ro) { | |
260 | dev_info(&nd_pfn->dev, | |
261 | "%s is read-only, unable to init metadata\n", | |
262 | dev_name(&nd_region->dev)); | |
263 | goto err; | |
264 | } | |
265 | ||
266 | memset(pfn_sb, 0, sizeof(*pfn_sb)); | |
267 | npfns = (pmem->size - SZ_8K) / SZ_4K; | |
268 | /* | |
269 | * Note, we use 64 here for the standard size of struct page, | |
270 | * debugging options may cause it to be larger in which case the | |
271 | * implementation will limit the pfns advertised through | |
272 | * ->direct_access() to those that are included in the memmap. | |
273 | */ | |
274 | if (nd_pfn->mode == PFN_MODE_PMEM) | |
275 | offset = ALIGN(SZ_8K + 64 * npfns, PMD_SIZE); | |
276 | else if (nd_pfn->mode == PFN_MODE_RAM) | |
277 | offset = SZ_8K; | |
278 | else | |
279 | goto err; | |
280 | ||
281 | npfns = (pmem->size - offset) / SZ_4K; | |
282 | pfn_sb->mode = cpu_to_le32(nd_pfn->mode); | |
283 | pfn_sb->dataoff = cpu_to_le64(offset); | |
284 | pfn_sb->npfns = cpu_to_le64(npfns); | |
285 | memcpy(pfn_sb->signature, PFN_SIG, PFN_SIG_LEN); | |
286 | memcpy(pfn_sb->uuid, nd_pfn->uuid, 16); | |
287 | pfn_sb->version_major = cpu_to_le16(1); | |
288 | checksum = nd_sb_checksum((struct nd_gen_sb *) pfn_sb); | |
289 | pfn_sb->checksum = cpu_to_le64(checksum); | |
290 | ||
291 | rc = nvdimm_write_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb)); | |
292 | if (rc) | |
293 | goto err; | |
294 | ||
295 | return 0; | |
296 | err: | |
297 | nd_pfn->pfn_sb = NULL; | |
298 | kfree(pfn_sb); | |
299 | return -ENXIO; | |
300 | } | |
301 | ||
302 | static int nvdimm_namespace_detach_pfn(struct nd_namespace_common *ndns) | |
303 | { | |
304 | struct nd_pfn *nd_pfn = to_nd_pfn(ndns->claim); | |
305 | struct pmem_device *pmem; | |
306 | ||
307 | /* free pmem disk */ | |
308 | pmem = dev_get_drvdata(&nd_pfn->dev); | |
309 | pmem_detach_disk(pmem); | |
310 | ||
311 | /* release nd_pfn resources */ | |
312 | kfree(nd_pfn->pfn_sb); | |
313 | nd_pfn->pfn_sb = NULL; | |
314 | ||
315 | return 0; | |
316 | } | |
317 | ||
318 | static int nvdimm_namespace_attach_pfn(struct nd_namespace_common *ndns) | |
9e853f23 | 319 | { |
32ab0a3f DW |
320 | struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); |
321 | struct nd_pfn *nd_pfn = to_nd_pfn(ndns->claim); | |
322 | struct device *dev = &nd_pfn->dev; | |
323 | struct vmem_altmap *altmap; | |
324 | struct nd_region *nd_region; | |
325 | struct nd_pfn_sb *pfn_sb; | |
326 | struct pmem_device *pmem; | |
327 | phys_addr_t offset; | |
328 | int rc; | |
329 | ||
330 | if (!nd_pfn->uuid || !nd_pfn->ndns) | |
331 | return -ENODEV; | |
332 | ||
333 | nd_region = to_nd_region(dev->parent); | |
334 | rc = nd_pfn_init(nd_pfn); | |
335 | if (rc) | |
336 | return rc; | |
337 | ||
338 | if (PAGE_SIZE != SZ_4K) { | |
339 | dev_err(dev, "only supported on systems with 4K PAGE_SIZE\n"); | |
340 | return -ENXIO; | |
341 | } | |
342 | if (nsio->res.start & ND_PFN_MASK) { | |
343 | dev_err(dev, "%s not memory hotplug section aligned\n", | |
344 | dev_name(&ndns->dev)); | |
345 | return -ENXIO; | |
346 | } | |
347 | ||
348 | pfn_sb = nd_pfn->pfn_sb; | |
349 | offset = le64_to_cpu(pfn_sb->dataoff); | |
350 | nd_pfn->mode = le32_to_cpu(nd_pfn->pfn_sb->mode); | |
351 | if (nd_pfn->mode == PFN_MODE_RAM) { | |
352 | if (offset != SZ_8K) | |
353 | return -EINVAL; | |
354 | nd_pfn->npfns = le64_to_cpu(pfn_sb->npfns); | |
355 | altmap = NULL; | |
356 | } else { | |
357 | rc = -ENXIO; | |
358 | goto err; | |
359 | } | |
360 | ||
361 | /* establish pfn range for lookup, and switch to direct map */ | |
362 | pmem = dev_get_drvdata(dev); | |
a639315d DW |
363 | devm_memunmap(dev, (void __force *) pmem->virt_addr); |
364 | pmem->virt_addr = (void __pmem *) devm_memremap_pages(dev, &nsio->res); | |
32ab0a3f DW |
365 | if (IS_ERR(pmem->virt_addr)) { |
366 | rc = PTR_ERR(pmem->virt_addr); | |
367 | goto err; | |
368 | } | |
369 | ||
370 | /* attach pmem disk in "pfn-mode" */ | |
371 | pmem->data_offset = offset; | |
372 | rc = pmem_attach_disk(dev, ndns, pmem); | |
373 | if (rc) | |
374 | goto err; | |
375 | ||
376 | return rc; | |
377 | err: | |
378 | nvdimm_namespace_detach_pfn(ndns); | |
379 | return rc; | |
9e853f23 RZ |
380 | } |
381 | ||
9f53f9fa | 382 | static int nd_pmem_probe(struct device *dev) |
9e853f23 | 383 | { |
9f53f9fa | 384 | struct nd_region *nd_region = to_nd_region(dev->parent); |
8c2f7e86 DW |
385 | struct nd_namespace_common *ndns; |
386 | struct nd_namespace_io *nsio; | |
9e853f23 | 387 | struct pmem_device *pmem; |
9e853f23 | 388 | |
8c2f7e86 DW |
389 | ndns = nvdimm_namespace_common_probe(dev); |
390 | if (IS_ERR(ndns)) | |
391 | return PTR_ERR(ndns); | |
bf9bccc1 | 392 | |
8c2f7e86 | 393 | nsio = to_nd_namespace_io(&ndns->dev); |
9f53f9fa | 394 | pmem = pmem_alloc(dev, &nsio->res, nd_region->id); |
9e853f23 RZ |
395 | if (IS_ERR(pmem)) |
396 | return PTR_ERR(pmem); | |
397 | ||
32ab0a3f | 398 | pmem->ndns = ndns; |
9f53f9fa | 399 | dev_set_drvdata(dev, pmem); |
8c2f7e86 | 400 | ndns->rw_bytes = pmem_rw_bytes; |
708ab62b | 401 | |
8c2f7e86 | 402 | if (is_nd_btt(dev)) |
708ab62b CH |
403 | return nvdimm_namespace_attach_btt(ndns); |
404 | ||
32ab0a3f DW |
405 | if (is_nd_pfn(dev)) |
406 | return nvdimm_namespace_attach_pfn(ndns); | |
407 | ||
408 | if (nd_btt_probe(ndns, pmem) == 0) { | |
8c2f7e86 | 409 | /* we'll come back as btt-pmem */ |
708ab62b | 410 | return -ENXIO; |
32ab0a3f DW |
411 | } |
412 | ||
413 | if (nd_pfn_probe(ndns, pmem) == 0) { | |
414 | /* we'll come back as pfn-pmem */ | |
415 | return -ENXIO; | |
416 | } | |
417 | ||
418 | return pmem_attach_disk(dev, ndns, pmem); | |
9e853f23 RZ |
419 | } |
420 | ||
9f53f9fa | 421 | static int nd_pmem_remove(struct device *dev) |
9e853f23 | 422 | { |
9f53f9fa | 423 | struct pmem_device *pmem = dev_get_drvdata(dev); |
9e853f23 | 424 | |
8c2f7e86 | 425 | if (is_nd_btt(dev)) |
32ab0a3f DW |
426 | nvdimm_namespace_detach_btt(pmem->ndns); |
427 | else if (is_nd_pfn(dev)) | |
428 | nvdimm_namespace_detach_pfn(pmem->ndns); | |
8c2f7e86 DW |
429 | else |
430 | pmem_detach_disk(pmem); | |
8c2f7e86 | 431 | |
9e853f23 RZ |
432 | return 0; |
433 | } | |
434 | ||
9f53f9fa DW |
435 | MODULE_ALIAS("pmem"); |
436 | MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_IO); | |
bf9bccc1 | 437 | MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_PMEM); |
9f53f9fa DW |
438 | static struct nd_device_driver nd_pmem_driver = { |
439 | .probe = nd_pmem_probe, | |
440 | .remove = nd_pmem_remove, | |
441 | .drv = { | |
442 | .name = "nd_pmem", | |
9e853f23 | 443 | }, |
bf9bccc1 | 444 | .type = ND_DRIVER_NAMESPACE_IO | ND_DRIVER_NAMESPACE_PMEM, |
9e853f23 RZ |
445 | }; |
446 | ||
447 | static int __init pmem_init(void) | |
448 | { | |
449 | int error; | |
450 | ||
451 | pmem_major = register_blkdev(0, "pmem"); | |
452 | if (pmem_major < 0) | |
453 | return pmem_major; | |
454 | ||
9f53f9fa DW |
455 | error = nd_driver_register(&nd_pmem_driver); |
456 | if (error) { | |
9e853f23 | 457 | unregister_blkdev(pmem_major, "pmem"); |
9f53f9fa DW |
458 | return error; |
459 | } | |
460 | ||
461 | return 0; | |
9e853f23 RZ |
462 | } |
463 | module_init(pmem_init); | |
464 | ||
465 | static void pmem_exit(void) | |
466 | { | |
9f53f9fa | 467 | driver_unregister(&nd_pmem_driver.drv); |
9e853f23 RZ |
468 | unregister_blkdev(pmem_major, "pmem"); |
469 | } | |
470 | module_exit(pmem_exit); | |
471 | ||
472 | MODULE_AUTHOR("Ross Zwisler <ross.zwisler@linux.intel.com>"); | |
473 | MODULE_LICENSE("GPL v2"); |