Commit | Line | Data |
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5b497af4 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
7b6be844 DW |
2 | /* |
3 | * Copyright(c) 2017 Intel Corporation. All rights reserved. | |
7b6be844 DW |
4 | */ |
5 | #include <linux/pagemap.h> | |
6 | #include <linux/module.h> | |
7 | #include <linux/mount.h> | |
75d4e06f | 8 | #include <linux/pseudo_fs.h> |
7b6be844 | 9 | #include <linux/magic.h> |
569d0365 | 10 | #include <linux/pfn_t.h> |
7b6be844 | 11 | #include <linux/cdev.h> |
7b6be844 | 12 | #include <linux/slab.h> |
7e026c8c | 13 | #include <linux/uio.h> |
6568b08b | 14 | #include <linux/dax.h> |
7b6be844 | 15 | #include <linux/fs.h> |
51cf784c | 16 | #include "dax-private.h" |
7b6be844 | 17 | |
1b764601 CH |
18 | /** |
19 | * struct dax_device - anchor object for dax services | |
20 | * @inode: core vfs | |
21 | * @cdev: optional character interface for "device dax" | |
1b764601 CH |
22 | * @private: dax driver private data |
23 | * @flags: state and boolean properties | |
db8cd5ef | 24 | * @ops: operations for this device |
8012b866 SR |
25 | * @holder_data: holder of a dax_device: could be filesystem or mapped device |
26 | * @holder_ops: operations for the inner holder | |
1b764601 CH |
27 | */ |
28 | struct dax_device { | |
1b764601 CH |
29 | struct inode inode; |
30 | struct cdev cdev; | |
1b764601 CH |
31 | void *private; |
32 | unsigned long flags; | |
33 | const struct dax_operations *ops; | |
8012b866 SR |
34 | void *holder_data; |
35 | const struct dax_holder_operations *holder_ops; | |
1b764601 CH |
36 | }; |
37 | ||
7b6be844 DW |
38 | static dev_t dax_devt; |
39 | DEFINE_STATIC_SRCU(dax_srcu); | |
40 | static struct vfsmount *dax_mnt; | |
41 | static DEFINE_IDA(dax_minor_ida); | |
42 | static struct kmem_cache *dax_cache __read_mostly; | |
43 | static struct super_block *dax_superblock __read_mostly; | |
44 | ||
45 | int dax_read_lock(void) | |
46 | { | |
47 | return srcu_read_lock(&dax_srcu); | |
48 | } | |
49 | EXPORT_SYMBOL_GPL(dax_read_lock); | |
50 | ||
51 | void dax_read_unlock(int id) | |
52 | { | |
53 | srcu_read_unlock(&dax_srcu, id); | |
54 | } | |
55 | EXPORT_SYMBOL_GPL(dax_read_unlock); | |
56 | ||
fb08a190 CH |
57 | #if defined(CONFIG_BLOCK) && defined(CONFIG_FS_DAX) |
58 | #include <linux/blkdev.h> | |
59 | ||
60 | static DEFINE_XARRAY(dax_hosts); | |
61 | ||
62 | int dax_add_host(struct dax_device *dax_dev, struct gendisk *disk) | |
1b764601 | 63 | { |
fb08a190 | 64 | return xa_insert(&dax_hosts, (unsigned long)disk, dax_dev, GFP_KERNEL); |
1b764601 | 65 | } |
fb08a190 | 66 | EXPORT_SYMBOL_GPL(dax_add_host); |
1b764601 | 67 | |
fb08a190 CH |
68 | void dax_remove_host(struct gendisk *disk) |
69 | { | |
70 | xa_erase(&dax_hosts, (unsigned long)disk); | |
71 | } | |
72 | EXPORT_SYMBOL_GPL(dax_remove_host); | |
e765f13e | 73 | |
1b764601 | 74 | /** |
fb08a190 CH |
75 | * fs_dax_get_by_bdev() - temporary lookup mechanism for filesystem-dax |
76 | * @bdev: block device to find a dax_device for | |
cd913c76 | 77 | * @start_off: returns the byte offset into the dax_device that @bdev starts |
8012b866 SR |
78 | * @holder: filesystem or mapped device inside the dax_device |
79 | * @ops: operations for the inner holder | |
1b764601 | 80 | */ |
8012b866 SR |
81 | struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev, u64 *start_off, |
82 | void *holder, const struct dax_holder_operations *ops) | |
1b764601 | 83 | { |
fb08a190 | 84 | struct dax_device *dax_dev; |
cd913c76 | 85 | u64 part_size; |
fb08a190 | 86 | int id; |
1b764601 | 87 | |
fb08a190 | 88 | if (!blk_queue_dax(bdev->bd_disk->queue)) |
1b764601 CH |
89 | return NULL; |
90 | ||
cd913c76 CH |
91 | *start_off = get_start_sect(bdev) * SECTOR_SIZE; |
92 | part_size = bdev_nr_sectors(bdev) * SECTOR_SIZE; | |
93 | if (*start_off % PAGE_SIZE || part_size % PAGE_SIZE) { | |
0c445871 CH |
94 | pr_info("%pg: error: unaligned partition for dax\n", bdev); |
95 | return NULL; | |
96 | } | |
97 | ||
1b764601 | 98 | id = dax_read_lock(); |
fb08a190 CH |
99 | dax_dev = xa_load(&dax_hosts, (unsigned long)bdev->bd_disk); |
100 | if (!dax_dev || !dax_alive(dax_dev) || !igrab(&dax_dev->inode)) | |
101 | dax_dev = NULL; | |
8012b866 SR |
102 | else if (holder) { |
103 | if (!cmpxchg(&dax_dev->holder_data, NULL, holder)) | |
104 | dax_dev->holder_ops = ops; | |
105 | else | |
106 | dax_dev = NULL; | |
107 | } | |
1b764601 CH |
108 | dax_read_unlock(id); |
109 | ||
fb08a190 | 110 | return dax_dev; |
78f35473 DW |
111 | } |
112 | EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev); | |
8012b866 SR |
113 | |
114 | void fs_put_dax(struct dax_device *dax_dev, void *holder) | |
115 | { | |
116 | if (dax_dev && holder && | |
117 | cmpxchg(&dax_dev->holder_data, holder, NULL) == holder) | |
118 | dax_dev->holder_ops = NULL; | |
119 | put_dax(dax_dev); | |
120 | } | |
121 | EXPORT_SYMBOL_GPL(fs_put_dax); | |
5d2a228b | 122 | #endif /* CONFIG_BLOCK && CONFIG_FS_DAX */ |
ef510424 | 123 | |
9a60c3ef DW |
124 | enum dax_device_flags { |
125 | /* !alive + rcu grace period == no new operations / mappings */ | |
126 | DAXDEV_ALIVE, | |
6e0c90d6 DW |
127 | /* gate whether dax_flush() calls the low level flush routine */ |
128 | DAXDEV_WRITE_CACHE, | |
fefc1d97 PG |
129 | /* flag to check if device supports synchronous flush */ |
130 | DAXDEV_SYNC, | |
7ac5360c CH |
131 | /* do not leave the caches dirty after writes */ |
132 | DAXDEV_NOCACHE, | |
133 | /* handle CPU fetch exceptions during reads */ | |
134 | DAXDEV_NOMC, | |
9a60c3ef DW |
135 | }; |
136 | ||
b0686260 DW |
137 | /** |
138 | * dax_direct_access() - translate a device pgoff to an absolute pfn | |
139 | * @dax_dev: a dax_device instance representing the logical memory range | |
140 | * @pgoff: offset in pages from the start of the device to translate | |
141 | * @nr_pages: number of consecutive pages caller can handle relative to @pfn | |
e511c4a3 | 142 | * @mode: indicator on normal access or recovery write |
b0686260 DW |
143 | * @kaddr: output parameter that returns a virtual address mapping of pfn |
144 | * @pfn: output parameter that returns an absolute pfn translation of @pgoff | |
145 | * | |
146 | * Return: negative errno if an error occurs, otherwise the number of | |
147 | * pages accessible at the device relative @pgoff. | |
148 | */ | |
149 | long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages, | |
e511c4a3 | 150 | enum dax_access_mode mode, void **kaddr, pfn_t *pfn) |
b0686260 DW |
151 | { |
152 | long avail; | |
153 | ||
b0686260 DW |
154 | if (!dax_dev) |
155 | return -EOPNOTSUPP; | |
156 | ||
157 | if (!dax_alive(dax_dev)) | |
158 | return -ENXIO; | |
159 | ||
160 | if (nr_pages < 0) | |
b05d4c57 | 161 | return -EINVAL; |
b0686260 DW |
162 | |
163 | avail = dax_dev->ops->direct_access(dax_dev, pgoff, nr_pages, | |
e511c4a3 | 164 | mode, kaddr, pfn); |
b0686260 DW |
165 | if (!avail) |
166 | return -ERANGE; | |
167 | return min(avail, nr_pages); | |
168 | } | |
169 | EXPORT_SYMBOL_GPL(dax_direct_access); | |
170 | ||
7e026c8c DW |
171 | size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr, |
172 | size_t bytes, struct iov_iter *i) | |
173 | { | |
174 | if (!dax_alive(dax_dev)) | |
175 | return 0; | |
176 | ||
7ac5360c CH |
177 | /* |
178 | * The userspace address for the memory copy has already been validated | |
179 | * via access_ok() in vfs_write, so use the 'no check' version to bypass | |
180 | * the HARDENED_USERCOPY overhead. | |
181 | */ | |
182 | if (test_bit(DAXDEV_NOCACHE, &dax_dev->flags)) | |
183 | return _copy_from_iter_flushcache(addr, bytes, i); | |
184 | return _copy_from_iter(addr, bytes, i); | |
7e026c8c | 185 | } |
7e026c8c | 186 | |
b3a9a0c3 DW |
187 | size_t dax_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr, |
188 | size_t bytes, struct iov_iter *i) | |
189 | { | |
190 | if (!dax_alive(dax_dev)) | |
191 | return 0; | |
192 | ||
7ac5360c CH |
193 | /* |
194 | * The userspace address for the memory copy has already been validated | |
195 | * via access_ok() in vfs_red, so use the 'no check' version to bypass | |
196 | * the HARDENED_USERCOPY overhead. | |
197 | */ | |
198 | if (test_bit(DAXDEV_NOMC, &dax_dev->flags)) | |
199 | return _copy_mc_to_iter(addr, bytes, i); | |
200 | return _copy_to_iter(addr, bytes, i); | |
b3a9a0c3 | 201 | } |
b3a9a0c3 | 202 | |
f605a263 VG |
203 | int dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff, |
204 | size_t nr_pages) | |
205 | { | |
206 | if (!dax_alive(dax_dev)) | |
207 | return -ENXIO; | |
f605a263 VG |
208 | /* |
209 | * There are no callers that want to zero more than one page as of now. | |
210 | * Once users are there, this check can be removed after the | |
211 | * device mapper code has been updated to split ranges across targets. | |
212 | */ | |
213 | if (nr_pages != 1) | |
214 | return -EIO; | |
215 | ||
216 | return dax_dev->ops->zero_page_range(dax_dev, pgoff, nr_pages); | |
217 | } | |
218 | EXPORT_SYMBOL_GPL(dax_zero_page_range); | |
219 | ||
047218ec JC |
220 | size_t dax_recovery_write(struct dax_device *dax_dev, pgoff_t pgoff, |
221 | void *addr, size_t bytes, struct iov_iter *iter) | |
222 | { | |
223 | if (!dax_dev->ops->recovery_write) | |
224 | return 0; | |
225 | return dax_dev->ops->recovery_write(dax_dev, pgoff, addr, bytes, iter); | |
226 | } | |
227 | EXPORT_SYMBOL_GPL(dax_recovery_write); | |
228 | ||
8012b866 SR |
229 | int dax_holder_notify_failure(struct dax_device *dax_dev, u64 off, |
230 | u64 len, int mf_flags) | |
231 | { | |
232 | int rc, id; | |
233 | ||
234 | id = dax_read_lock(); | |
235 | if (!dax_alive(dax_dev)) { | |
236 | rc = -ENXIO; | |
237 | goto out; | |
238 | } | |
239 | ||
240 | if (!dax_dev->holder_ops) { | |
241 | rc = -EOPNOTSUPP; | |
242 | goto out; | |
243 | } | |
244 | ||
245 | rc = dax_dev->holder_ops->notify_failure(dax_dev, off, len, mf_flags); | |
246 | out: | |
247 | dax_read_unlock(id); | |
248 | return rc; | |
249 | } | |
250 | EXPORT_SYMBOL_GPL(dax_holder_notify_failure); | |
251 | ||
c3ca015f MP |
252 | #ifdef CONFIG_ARCH_HAS_PMEM_API |
253 | void arch_wb_cache_pmem(void *addr, size_t size); | |
254 | void dax_flush(struct dax_device *dax_dev, void *addr, size_t size) | |
abebfbe2 | 255 | { |
808c340b | 256 | if (unlikely(!dax_write_cache_enabled(dax_dev))) |
6e0c90d6 DW |
257 | return; |
258 | ||
c3ca015f | 259 | arch_wb_cache_pmem(addr, size); |
abebfbe2 | 260 | } |
c3ca015f MP |
261 | #else |
262 | void dax_flush(struct dax_device *dax_dev, void *addr, size_t size) | |
263 | { | |
264 | } | |
265 | #endif | |
abebfbe2 DW |
266 | EXPORT_SYMBOL_GPL(dax_flush); |
267 | ||
6e0c90d6 DW |
268 | void dax_write_cache(struct dax_device *dax_dev, bool wc) |
269 | { | |
270 | if (wc) | |
271 | set_bit(DAXDEV_WRITE_CACHE, &dax_dev->flags); | |
272 | else | |
273 | clear_bit(DAXDEV_WRITE_CACHE, &dax_dev->flags); | |
274 | } | |
275 | EXPORT_SYMBOL_GPL(dax_write_cache); | |
276 | ||
273752c9 VG |
277 | bool dax_write_cache_enabled(struct dax_device *dax_dev) |
278 | { | |
279 | return test_bit(DAXDEV_WRITE_CACHE, &dax_dev->flags); | |
280 | } | |
281 | EXPORT_SYMBOL_GPL(dax_write_cache_enabled); | |
282 | ||
fd1d00ec | 283 | bool dax_synchronous(struct dax_device *dax_dev) |
fefc1d97 PG |
284 | { |
285 | return test_bit(DAXDEV_SYNC, &dax_dev->flags); | |
286 | } | |
fd1d00ec | 287 | EXPORT_SYMBOL_GPL(dax_synchronous); |
fefc1d97 | 288 | |
fd1d00ec | 289 | void set_dax_synchronous(struct dax_device *dax_dev) |
fefc1d97 PG |
290 | { |
291 | set_bit(DAXDEV_SYNC, &dax_dev->flags); | |
292 | } | |
fd1d00ec | 293 | EXPORT_SYMBOL_GPL(set_dax_synchronous); |
fefc1d97 | 294 | |
7ac5360c CH |
295 | void set_dax_nocache(struct dax_device *dax_dev) |
296 | { | |
297 | set_bit(DAXDEV_NOCACHE, &dax_dev->flags); | |
298 | } | |
299 | EXPORT_SYMBOL_GPL(set_dax_nocache); | |
300 | ||
301 | void set_dax_nomc(struct dax_device *dax_dev) | |
302 | { | |
303 | set_bit(DAXDEV_NOMC, &dax_dev->flags); | |
304 | } | |
305 | EXPORT_SYMBOL_GPL(set_dax_nomc); | |
306 | ||
7b6be844 DW |
307 | bool dax_alive(struct dax_device *dax_dev) |
308 | { | |
309 | lockdep_assert_held(&dax_srcu); | |
9a60c3ef | 310 | return test_bit(DAXDEV_ALIVE, &dax_dev->flags); |
7b6be844 DW |
311 | } |
312 | EXPORT_SYMBOL_GPL(dax_alive); | |
313 | ||
314 | /* | |
315 | * Note, rcu is not protecting the liveness of dax_dev, rcu is ensuring | |
316 | * that any fault handlers or operations that might have seen | |
317 | * dax_alive(), have completed. Any operations that start after | |
318 | * synchronize_srcu() has run will abort upon seeing !dax_alive(). | |
319 | */ | |
320 | void kill_dax(struct dax_device *dax_dev) | |
321 | { | |
322 | if (!dax_dev) | |
323 | return; | |
324 | ||
8012b866 SR |
325 | if (dax_dev->holder_data != NULL) |
326 | dax_holder_notify_failure(dax_dev, 0, U64_MAX, 0); | |
327 | ||
9a60c3ef | 328 | clear_bit(DAXDEV_ALIVE, &dax_dev->flags); |
7b6be844 | 329 | synchronize_srcu(&dax_srcu); |
8012b866 SR |
330 | |
331 | /* clear holder data */ | |
332 | dax_dev->holder_ops = NULL; | |
333 | dax_dev->holder_data = NULL; | |
7b6be844 DW |
334 | } |
335 | EXPORT_SYMBOL_GPL(kill_dax); | |
336 | ||
9567da0b DW |
337 | void run_dax(struct dax_device *dax_dev) |
338 | { | |
339 | set_bit(DAXDEV_ALIVE, &dax_dev->flags); | |
340 | } | |
341 | EXPORT_SYMBOL_GPL(run_dax); | |
342 | ||
7b6be844 DW |
343 | static struct inode *dax_alloc_inode(struct super_block *sb) |
344 | { | |
345 | struct dax_device *dax_dev; | |
b9d39d17 | 346 | struct inode *inode; |
7b6be844 | 347 | |
fd60b288 | 348 | dax_dev = alloc_inode_sb(sb, dax_cache, GFP_KERNEL); |
9f586fff MP |
349 | if (!dax_dev) |
350 | return NULL; | |
351 | ||
b9d39d17 DW |
352 | inode = &dax_dev->inode; |
353 | inode->i_rdev = 0; | |
354 | return inode; | |
7b6be844 DW |
355 | } |
356 | ||
357 | static struct dax_device *to_dax_dev(struct inode *inode) | |
358 | { | |
359 | return container_of(inode, struct dax_device, inode); | |
360 | } | |
361 | ||
53e22829 | 362 | static void dax_free_inode(struct inode *inode) |
7b6be844 | 363 | { |
7b6be844 | 364 | struct dax_device *dax_dev = to_dax_dev(inode); |
b9d39d17 | 365 | if (inode->i_rdev) |
0f702033 | 366 | ida_free(&dax_minor_ida, iminor(inode)); |
7b6be844 DW |
367 | kmem_cache_free(dax_cache, dax_dev); |
368 | } | |
369 | ||
370 | static void dax_destroy_inode(struct inode *inode) | |
371 | { | |
372 | struct dax_device *dax_dev = to_dax_dev(inode); | |
9a60c3ef | 373 | WARN_ONCE(test_bit(DAXDEV_ALIVE, &dax_dev->flags), |
7b6be844 | 374 | "kill_dax() must be called before final iput()\n"); |
7b6be844 DW |
375 | } |
376 | ||
377 | static const struct super_operations dax_sops = { | |
378 | .statfs = simple_statfs, | |
379 | .alloc_inode = dax_alloc_inode, | |
380 | .destroy_inode = dax_destroy_inode, | |
53e22829 | 381 | .free_inode = dax_free_inode, |
7b6be844 DW |
382 | .drop_inode = generic_delete_inode, |
383 | }; | |
384 | ||
75d4e06f | 385 | static int dax_init_fs_context(struct fs_context *fc) |
7b6be844 | 386 | { |
75d4e06f DH |
387 | struct pseudo_fs_context *ctx = init_pseudo(fc, DAXFS_MAGIC); |
388 | if (!ctx) | |
389 | return -ENOMEM; | |
390 | ctx->ops = &dax_sops; | |
391 | return 0; | |
7b6be844 DW |
392 | } |
393 | ||
394 | static struct file_system_type dax_fs_type = { | |
75d4e06f DH |
395 | .name = "dax", |
396 | .init_fs_context = dax_init_fs_context, | |
397 | .kill_sb = kill_anon_super, | |
7b6be844 DW |
398 | }; |
399 | ||
400 | static int dax_test(struct inode *inode, void *data) | |
401 | { | |
402 | dev_t devt = *(dev_t *) data; | |
403 | ||
404 | return inode->i_rdev == devt; | |
405 | } | |
406 | ||
407 | static int dax_set(struct inode *inode, void *data) | |
408 | { | |
409 | dev_t devt = *(dev_t *) data; | |
410 | ||
411 | inode->i_rdev = devt; | |
412 | return 0; | |
413 | } | |
414 | ||
415 | static struct dax_device *dax_dev_get(dev_t devt) | |
416 | { | |
417 | struct dax_device *dax_dev; | |
418 | struct inode *inode; | |
419 | ||
420 | inode = iget5_locked(dax_superblock, hash_32(devt + DAXFS_MAGIC, 31), | |
421 | dax_test, dax_set, &devt); | |
422 | ||
423 | if (!inode) | |
424 | return NULL; | |
425 | ||
426 | dax_dev = to_dax_dev(inode); | |
427 | if (inode->i_state & I_NEW) { | |
9a60c3ef | 428 | set_bit(DAXDEV_ALIVE, &dax_dev->flags); |
7b6be844 DW |
429 | inode->i_cdev = &dax_dev->cdev; |
430 | inode->i_mode = S_IFCHR; | |
431 | inode->i_flags = S_DAX; | |
432 | mapping_set_gfp_mask(&inode->i_data, GFP_USER); | |
433 | unlock_new_inode(inode); | |
434 | } | |
435 | ||
436 | return dax_dev; | |
437 | } | |
438 | ||
30c6828a | 439 | struct dax_device *alloc_dax(void *private, const struct dax_operations *ops) |
7b6be844 DW |
440 | { |
441 | struct dax_device *dax_dev; | |
442 | dev_t devt; | |
443 | int minor; | |
444 | ||
fb08a190 | 445 | if (WARN_ON_ONCE(ops && !ops->zero_page_range)) |
4e4ced93 | 446 | return ERR_PTR(-EINVAL); |
72058005 | 447 | |
0f702033 | 448 | minor = ida_alloc_max(&dax_minor_ida, MINORMASK, GFP_KERNEL); |
7b6be844 | 449 | if (minor < 0) |
fb08a190 | 450 | return ERR_PTR(-ENOMEM); |
7b6be844 DW |
451 | |
452 | devt = MKDEV(MAJOR(dax_devt), minor); | |
453 | dax_dev = dax_dev_get(devt); | |
454 | if (!dax_dev) | |
72058005 | 455 | goto err_dev; |
7b6be844 | 456 | |
6568b08b | 457 | dax_dev->ops = ops; |
7b6be844 DW |
458 | dax_dev->private = private; |
459 | return dax_dev; | |
460 | ||
72058005 | 461 | err_dev: |
0f702033 | 462 | ida_free(&dax_minor_ida, minor); |
4e4ced93 | 463 | return ERR_PTR(-ENOMEM); |
7b6be844 DW |
464 | } |
465 | EXPORT_SYMBOL_GPL(alloc_dax); | |
466 | ||
467 | void put_dax(struct dax_device *dax_dev) | |
468 | { | |
469 | if (!dax_dev) | |
470 | return; | |
471 | iput(&dax_dev->inode); | |
472 | } | |
473 | EXPORT_SYMBOL_GPL(put_dax); | |
474 | ||
8012b866 SR |
475 | /** |
476 | * dax_holder() - obtain the holder of a dax device | |
477 | * @dax_dev: a dax_device instance | |
1c88b9ba | 478 | * |
8012b866 SR |
479 | * Return: the holder's data which represents the holder if registered, |
480 | * otherwize NULL. | |
481 | */ | |
482 | void *dax_holder(struct dax_device *dax_dev) | |
483 | { | |
484 | return dax_dev->holder_data; | |
485 | } | |
486 | EXPORT_SYMBOL_GPL(dax_holder); | |
487 | ||
7b6be844 DW |
488 | /** |
489 | * inode_dax: convert a public inode into its dax_dev | |
490 | * @inode: An inode with i_cdev pointing to a dax_dev | |
491 | * | |
492 | * Note this is not equivalent to to_dax_dev() which is for private | |
493 | * internal use where we know the inode filesystem type == dax_fs_type. | |
494 | */ | |
495 | struct dax_device *inode_dax(struct inode *inode) | |
496 | { | |
497 | struct cdev *cdev = inode->i_cdev; | |
498 | ||
499 | return container_of(cdev, struct dax_device, cdev); | |
500 | } | |
501 | EXPORT_SYMBOL_GPL(inode_dax); | |
502 | ||
503 | struct inode *dax_inode(struct dax_device *dax_dev) | |
504 | { | |
505 | return &dax_dev->inode; | |
506 | } | |
507 | EXPORT_SYMBOL_GPL(dax_inode); | |
508 | ||
509 | void *dax_get_private(struct dax_device *dax_dev) | |
510 | { | |
9567da0b DW |
511 | if (!test_bit(DAXDEV_ALIVE, &dax_dev->flags)) |
512 | return NULL; | |
7b6be844 DW |
513 | return dax_dev->private; |
514 | } | |
515 | EXPORT_SYMBOL_GPL(dax_get_private); | |
516 | ||
517 | static void init_once(void *_dax_dev) | |
518 | { | |
519 | struct dax_device *dax_dev = _dax_dev; | |
520 | struct inode *inode = &dax_dev->inode; | |
521 | ||
b9d39d17 | 522 | memset(dax_dev, 0, sizeof(*dax_dev)); |
7b6be844 DW |
523 | inode_init_once(inode); |
524 | } | |
525 | ||
9567da0b | 526 | static int dax_fs_init(void) |
7b6be844 DW |
527 | { |
528 | int rc; | |
529 | ||
530 | dax_cache = kmem_cache_create("dax_cache", sizeof(struct dax_device), 0, | |
531 | (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| | |
532 | SLAB_MEM_SPREAD|SLAB_ACCOUNT), | |
533 | init_once); | |
534 | if (!dax_cache) | |
535 | return -ENOMEM; | |
536 | ||
7b6be844 DW |
537 | dax_mnt = kern_mount(&dax_fs_type); |
538 | if (IS_ERR(dax_mnt)) { | |
539 | rc = PTR_ERR(dax_mnt); | |
540 | goto err_mount; | |
541 | } | |
542 | dax_superblock = dax_mnt->mnt_sb; | |
543 | ||
544 | return 0; | |
545 | ||
546 | err_mount: | |
7b6be844 DW |
547 | kmem_cache_destroy(dax_cache); |
548 | ||
549 | return rc; | |
550 | } | |
551 | ||
9567da0b | 552 | static void dax_fs_exit(void) |
7b6be844 DW |
553 | { |
554 | kern_unmount(dax_mnt); | |
a7e8de82 | 555 | rcu_barrier(); |
7b6be844 DW |
556 | kmem_cache_destroy(dax_cache); |
557 | } | |
558 | ||
9567da0b | 559 | static int __init dax_core_init(void) |
7b6be844 DW |
560 | { |
561 | int rc; | |
562 | ||
9567da0b | 563 | rc = dax_fs_init(); |
7b6be844 DW |
564 | if (rc) |
565 | return rc; | |
566 | ||
cf1e2289 | 567 | rc = alloc_chrdev_region(&dax_devt, 0, MINORMASK+1, "dax"); |
7b6be844 | 568 | if (rc) |
9567da0b DW |
569 | goto err_chrdev; |
570 | ||
571 | rc = dax_bus_init(); | |
572 | if (rc) | |
573 | goto err_bus; | |
574 | return 0; | |
575 | ||
576 | err_bus: | |
577 | unregister_chrdev_region(dax_devt, MINORMASK+1); | |
578 | err_chrdev: | |
579 | dax_fs_exit(); | |
580 | return 0; | |
7b6be844 DW |
581 | } |
582 | ||
9567da0b | 583 | static void __exit dax_core_exit(void) |
7b6be844 | 584 | { |
1aa57431 | 585 | dax_bus_exit(); |
cf1e2289 | 586 | unregister_chrdev_region(dax_devt, MINORMASK+1); |
7b6be844 | 587 | ida_destroy(&dax_minor_ida); |
9567da0b | 588 | dax_fs_exit(); |
7b6be844 DW |
589 | } |
590 | ||
591 | MODULE_AUTHOR("Intel Corporation"); | |
592 | MODULE_LICENSE("GPL v2"); | |
9567da0b DW |
593 | subsys_initcall(dax_core_init); |
594 | module_exit(dax_core_exit); |