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ab68f262 | 1 | /* |
7b6be844 | 2 | * Copyright(c) 2016 - 2017 Intel Corporation. All rights reserved. |
ab68f262 DW |
3 | * |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of version 2 of the GNU General Public License as | |
6 | * published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, but | |
9 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
11 | * General Public License for more details. | |
12 | */ | |
13 | #include <linux/pagemap.h> | |
14 | #include <linux/module.h> | |
15 | #include <linux/device.h> | |
16 | #include <linux/pfn_t.h> | |
ba09c01d | 17 | #include <linux/cdev.h> |
ab68f262 DW |
18 | #include <linux/slab.h> |
19 | #include <linux/dax.h> | |
20 | #include <linux/fs.h> | |
21 | #include <linux/mm.h> | |
efebc711 | 22 | #include "dax-private.h" |
ccdb07f6 | 23 | #include "dax.h" |
ab68f262 | 24 | |
ab68f262 | 25 | static struct class *dax_class; |
ab68f262 | 26 | |
565851c9 DW |
27 | /* |
28 | * Rely on the fact that drvdata is set before the attributes are | |
29 | * registered, and that the attributes are unregistered before drvdata | |
30 | * is cleared to assume that drvdata is always valid. | |
31 | */ | |
d7fe1a67 DW |
32 | static ssize_t id_show(struct device *dev, |
33 | struct device_attribute *attr, char *buf) | |
34 | { | |
565851c9 | 35 | struct dax_region *dax_region = dev_get_drvdata(dev); |
d7fe1a67 | 36 | |
565851c9 | 37 | return sprintf(buf, "%d\n", dax_region->id); |
d7fe1a67 DW |
38 | } |
39 | static DEVICE_ATTR_RO(id); | |
40 | ||
41 | static ssize_t region_size_show(struct device *dev, | |
42 | struct device_attribute *attr, char *buf) | |
43 | { | |
565851c9 | 44 | struct dax_region *dax_region = dev_get_drvdata(dev); |
d7fe1a67 | 45 | |
565851c9 DW |
46 | return sprintf(buf, "%llu\n", (unsigned long long) |
47 | resource_size(&dax_region->res)); | |
d7fe1a67 DW |
48 | } |
49 | static struct device_attribute dev_attr_region_size = __ATTR(size, 0444, | |
50 | region_size_show, NULL); | |
51 | ||
52 | static ssize_t align_show(struct device *dev, | |
53 | struct device_attribute *attr, char *buf) | |
54 | { | |
565851c9 | 55 | struct dax_region *dax_region = dev_get_drvdata(dev); |
d7fe1a67 | 56 | |
565851c9 | 57 | return sprintf(buf, "%u\n", dax_region->align); |
d7fe1a67 DW |
58 | } |
59 | static DEVICE_ATTR_RO(align); | |
60 | ||
61 | static struct attribute *dax_region_attributes[] = { | |
62 | &dev_attr_region_size.attr, | |
63 | &dev_attr_align.attr, | |
64 | &dev_attr_id.attr, | |
65 | NULL, | |
66 | }; | |
67 | ||
68 | static const struct attribute_group dax_region_attribute_group = { | |
69 | .name = "dax_region", | |
70 | .attrs = dax_region_attributes, | |
71 | }; | |
72 | ||
73 | static const struct attribute_group *dax_region_attribute_groups[] = { | |
74 | &dax_region_attribute_group, | |
75 | NULL, | |
76 | }; | |
77 | ||
ab68f262 DW |
78 | static void dax_region_free(struct kref *kref) |
79 | { | |
80 | struct dax_region *dax_region; | |
81 | ||
82 | dax_region = container_of(kref, struct dax_region, kref); | |
83 | kfree(dax_region); | |
84 | } | |
85 | ||
86 | void dax_region_put(struct dax_region *dax_region) | |
ab68f262 | 87 | { |
ab68f262 | 88 | kref_put(&dax_region->kref, dax_region_free); |
ab68f262 | 89 | } |
ab68f262 | 90 | EXPORT_SYMBOL_GPL(dax_region_put); |
ab68f262 | 91 | |
d7fe1a67 DW |
92 | static void dax_region_unregister(void *region) |
93 | { | |
94 | struct dax_region *dax_region = region; | |
95 | ||
96 | sysfs_remove_groups(&dax_region->dev->kobj, | |
97 | dax_region_attribute_groups); | |
98 | dax_region_put(dax_region); | |
99 | } | |
100 | ||
ab68f262 DW |
101 | struct dax_region *alloc_dax_region(struct device *parent, int region_id, |
102 | struct resource *res, unsigned int align, void *addr, | |
103 | unsigned long pfn_flags) | |
104 | { | |
105 | struct dax_region *dax_region; | |
106 | ||
d7fe1a67 DW |
107 | /* |
108 | * The DAX core assumes that it can store its private data in | |
109 | * parent->driver_data. This WARN is a reminder / safeguard for | |
110 | * developers of device-dax drivers. | |
111 | */ | |
112 | if (dev_get_drvdata(parent)) { | |
113 | dev_WARN(parent, "dax core failed to setup private data\n"); | |
114 | return NULL; | |
115 | } | |
116 | ||
9d2d01a0 DW |
117 | if (!IS_ALIGNED(res->start, align) |
118 | || !IS_ALIGNED(resource_size(res), align)) | |
119 | return NULL; | |
ab68f262 | 120 | |
9d2d01a0 | 121 | dax_region = kzalloc(sizeof(*dax_region), GFP_KERNEL); |
ab68f262 DW |
122 | if (!dax_region) |
123 | return NULL; | |
124 | ||
d7fe1a67 | 125 | dev_set_drvdata(parent, dax_region); |
ab68f262 DW |
126 | memcpy(&dax_region->res, res, sizeof(*res)); |
127 | dax_region->pfn_flags = pfn_flags; | |
128 | kref_init(&dax_region->kref); | |
129 | dax_region->id = region_id; | |
130 | ida_init(&dax_region->ida); | |
131 | dax_region->align = align; | |
132 | dax_region->dev = parent; | |
133 | dax_region->base = addr; | |
d7fe1a67 DW |
134 | if (sysfs_create_groups(&parent->kobj, dax_region_attribute_groups)) { |
135 | kfree(dax_region); | |
136 | return NULL;; | |
137 | } | |
ab68f262 | 138 | |
d7fe1a67 DW |
139 | kref_get(&dax_region->kref); |
140 | if (devm_add_action_or_reset(parent, dax_region_unregister, dax_region)) | |
141 | return NULL; | |
ab68f262 DW |
142 | return dax_region; |
143 | } | |
144 | EXPORT_SYMBOL_GPL(alloc_dax_region); | |
145 | ||
5f0694b3 | 146 | static struct dev_dax *to_dev_dax(struct device *dev) |
ebd84d72 | 147 | { |
5f0694b3 | 148 | return container_of(dev, struct dev_dax, dev); |
ebd84d72 DW |
149 | } |
150 | ||
ab68f262 DW |
151 | static ssize_t size_show(struct device *dev, |
152 | struct device_attribute *attr, char *buf) | |
153 | { | |
5f0694b3 | 154 | struct dev_dax *dev_dax = to_dev_dax(dev); |
ab68f262 DW |
155 | unsigned long long size = 0; |
156 | int i; | |
157 | ||
5f0694b3 DW |
158 | for (i = 0; i < dev_dax->num_resources; i++) |
159 | size += resource_size(&dev_dax->res[i]); | |
ab68f262 DW |
160 | |
161 | return sprintf(buf, "%llu\n", size); | |
162 | } | |
163 | static DEVICE_ATTR_RO(size); | |
164 | ||
5f0694b3 | 165 | static struct attribute *dev_dax_attributes[] = { |
ab68f262 DW |
166 | &dev_attr_size.attr, |
167 | NULL, | |
168 | }; | |
169 | ||
5f0694b3 DW |
170 | static const struct attribute_group dev_dax_attribute_group = { |
171 | .attrs = dev_dax_attributes, | |
ab68f262 DW |
172 | }; |
173 | ||
174 | static const struct attribute_group *dax_attribute_groups[] = { | |
5f0694b3 | 175 | &dev_dax_attribute_group, |
ab68f262 DW |
176 | NULL, |
177 | }; | |
178 | ||
5f0694b3 | 179 | static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma, |
dee41079 DW |
180 | const char *func) |
181 | { | |
5f0694b3 DW |
182 | struct dax_region *dax_region = dev_dax->region; |
183 | struct device *dev = &dev_dax->dev; | |
dee41079 DW |
184 | unsigned long mask; |
185 | ||
7b6be844 | 186 | if (!dax_alive(dev_dax->dax_dev)) |
dee41079 DW |
187 | return -ENXIO; |
188 | ||
4cb19355 | 189 | /* prevent private mappings from being established */ |
325896ff | 190 | if ((vma->vm_flags & VM_MAYSHARE) != VM_MAYSHARE) { |
0aa88fda JM |
191 | dev_info_ratelimited(dev, |
192 | "%s: %s: fail, attempted private mapping\n", | |
dee41079 DW |
193 | current->comm, func); |
194 | return -EINVAL; | |
195 | } | |
196 | ||
197 | mask = dax_region->align - 1; | |
198 | if (vma->vm_start & mask || vma->vm_end & mask) { | |
0aa88fda JM |
199 | dev_info_ratelimited(dev, |
200 | "%s: %s: fail, unaligned vma (%#lx - %#lx, %#lx)\n", | |
dee41079 DW |
201 | current->comm, func, vma->vm_start, vma->vm_end, |
202 | mask); | |
203 | return -EINVAL; | |
204 | } | |
205 | ||
206 | if ((dax_region->pfn_flags & (PFN_DEV|PFN_MAP)) == PFN_DEV | |
207 | && (vma->vm_flags & VM_DONTCOPY) == 0) { | |
0aa88fda JM |
208 | dev_info_ratelimited(dev, |
209 | "%s: %s: fail, dax range requires MADV_DONTFORK\n", | |
dee41079 DW |
210 | current->comm, func); |
211 | return -EINVAL; | |
212 | } | |
213 | ||
214 | if (!vma_is_dax(vma)) { | |
0aa88fda JM |
215 | dev_info_ratelimited(dev, |
216 | "%s: %s: fail, vma is not DAX capable\n", | |
dee41079 DW |
217 | current->comm, func); |
218 | return -EINVAL; | |
219 | } | |
220 | ||
221 | return 0; | |
222 | } | |
223 | ||
efebc711 | 224 | /* see "strong" declaration in tools/testing/nvdimm/dax-dev.c */ |
73616367 | 225 | __weak phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff, |
dee41079 DW |
226 | unsigned long size) |
227 | { | |
228 | struct resource *res; | |
4684da79 RZ |
229 | /* gcc-4.6.3-nolibc for i386 complains that this is uninitialized */ |
230 | phys_addr_t uninitialized_var(phys); | |
dee41079 DW |
231 | int i; |
232 | ||
5f0694b3 DW |
233 | for (i = 0; i < dev_dax->num_resources; i++) { |
234 | res = &dev_dax->res[i]; | |
dee41079 DW |
235 | phys = pgoff * PAGE_SIZE + res->start; |
236 | if (phys >= res->start && phys <= res->end) | |
237 | break; | |
238 | pgoff -= PHYS_PFN(resource_size(res)); | |
239 | } | |
240 | ||
5f0694b3 DW |
241 | if (i < dev_dax->num_resources) { |
242 | res = &dev_dax->res[i]; | |
dee41079 DW |
243 | if (phys + size - 1 <= res->end) |
244 | return phys; | |
245 | } | |
246 | ||
247 | return -1; | |
248 | } | |
249 | ||
5f0694b3 | 250 | static int __dev_dax_pte_fault(struct dev_dax *dev_dax, struct vm_fault *vmf) |
dee41079 | 251 | { |
5f0694b3 | 252 | struct device *dev = &dev_dax->dev; |
dee41079 DW |
253 | struct dax_region *dax_region; |
254 | int rc = VM_FAULT_SIGBUS; | |
255 | phys_addr_t phys; | |
256 | pfn_t pfn; | |
0134ed4f | 257 | unsigned int fault_size = PAGE_SIZE; |
dee41079 | 258 | |
5f0694b3 | 259 | if (check_vma(dev_dax, vmf->vma, __func__)) |
dee41079 DW |
260 | return VM_FAULT_SIGBUS; |
261 | ||
5f0694b3 | 262 | dax_region = dev_dax->region; |
dee41079 | 263 | if (dax_region->align > PAGE_SIZE) { |
76202620 OH |
264 | dev_dbg(dev, "%s: alignment (%#x) > fault size (%#x)\n", |
265 | __func__, dax_region->align, fault_size); | |
dee41079 DW |
266 | return VM_FAULT_SIGBUS; |
267 | } | |
268 | ||
0134ed4f DJ |
269 | if (fault_size != dax_region->align) |
270 | return VM_FAULT_SIGBUS; | |
271 | ||
73616367 | 272 | phys = dax_pgoff_to_phys(dev_dax, vmf->pgoff, PAGE_SIZE); |
dee41079 | 273 | if (phys == -1) { |
52084f89 | 274 | dev_dbg(dev, "%s: pgoff_to_phys(%#lx) failed\n", __func__, |
dee41079 DW |
275 | vmf->pgoff); |
276 | return VM_FAULT_SIGBUS; | |
277 | } | |
278 | ||
279 | pfn = phys_to_pfn_t(phys, dax_region->pfn_flags); | |
280 | ||
11bac800 | 281 | rc = vm_insert_mixed(vmf->vma, vmf->address, pfn); |
dee41079 DW |
282 | |
283 | if (rc == -ENOMEM) | |
284 | return VM_FAULT_OOM; | |
285 | if (rc < 0 && rc != -EBUSY) | |
286 | return VM_FAULT_SIGBUS; | |
287 | ||
288 | return VM_FAULT_NOPAGE; | |
289 | } | |
290 | ||
5f0694b3 | 291 | static int __dev_dax_pmd_fault(struct dev_dax *dev_dax, struct vm_fault *vmf) |
dee41079 | 292 | { |
d8a849e1 | 293 | unsigned long pmd_addr = vmf->address & PMD_MASK; |
5f0694b3 | 294 | struct device *dev = &dev_dax->dev; |
dee41079 DW |
295 | struct dax_region *dax_region; |
296 | phys_addr_t phys; | |
297 | pgoff_t pgoff; | |
298 | pfn_t pfn; | |
0134ed4f | 299 | unsigned int fault_size = PMD_SIZE; |
dee41079 | 300 | |
5f0694b3 | 301 | if (check_vma(dev_dax, vmf->vma, __func__)) |
dee41079 DW |
302 | return VM_FAULT_SIGBUS; |
303 | ||
5f0694b3 | 304 | dax_region = dev_dax->region; |
dee41079 | 305 | if (dax_region->align > PMD_SIZE) { |
76202620 OH |
306 | dev_dbg(dev, "%s: alignment (%#x) > fault size (%#x)\n", |
307 | __func__, dax_region->align, fault_size); | |
dee41079 DW |
308 | return VM_FAULT_SIGBUS; |
309 | } | |
310 | ||
311 | /* dax pmd mappings require pfn_t_devmap() */ | |
312 | if ((dax_region->pfn_flags & (PFN_DEV|PFN_MAP)) != (PFN_DEV|PFN_MAP)) { | |
76202620 | 313 | dev_dbg(dev, "%s: region lacks devmap flags\n", __func__); |
dee41079 DW |
314 | return VM_FAULT_SIGBUS; |
315 | } | |
316 | ||
0134ed4f DJ |
317 | if (fault_size < dax_region->align) |
318 | return VM_FAULT_SIGBUS; | |
319 | else if (fault_size > dax_region->align) | |
320 | return VM_FAULT_FALLBACK; | |
321 | ||
322 | /* if we are outside of the VMA */ | |
323 | if (pmd_addr < vmf->vma->vm_start || | |
324 | (pmd_addr + PMD_SIZE) > vmf->vma->vm_end) | |
325 | return VM_FAULT_SIGBUS; | |
326 | ||
f4200391 | 327 | pgoff = linear_page_index(vmf->vma, pmd_addr); |
73616367 | 328 | phys = dax_pgoff_to_phys(dev_dax, pgoff, PMD_SIZE); |
dee41079 | 329 | if (phys == -1) { |
52084f89 | 330 | dev_dbg(dev, "%s: pgoff_to_phys(%#lx) failed\n", __func__, |
dee41079 DW |
331 | pgoff); |
332 | return VM_FAULT_SIGBUS; | |
333 | } | |
334 | ||
335 | pfn = phys_to_pfn_t(phys, dax_region->pfn_flags); | |
336 | ||
f4200391 | 337 | return vmf_insert_pfn_pmd(vmf->vma, vmf->address, vmf->pmd, pfn, |
d8a849e1 | 338 | vmf->flags & FAULT_FLAG_WRITE); |
dee41079 DW |
339 | } |
340 | ||
9557feee | 341 | #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD |
5f0694b3 | 342 | static int __dev_dax_pud_fault(struct dev_dax *dev_dax, struct vm_fault *vmf) |
9557feee DJ |
343 | { |
344 | unsigned long pud_addr = vmf->address & PUD_MASK; | |
5f0694b3 | 345 | struct device *dev = &dev_dax->dev; |
9557feee DJ |
346 | struct dax_region *dax_region; |
347 | phys_addr_t phys; | |
348 | pgoff_t pgoff; | |
349 | pfn_t pfn; | |
70b085b0 DJ |
350 | unsigned int fault_size = PUD_SIZE; |
351 | ||
9557feee | 352 | |
5f0694b3 | 353 | if (check_vma(dev_dax, vmf->vma, __func__)) |
9557feee DJ |
354 | return VM_FAULT_SIGBUS; |
355 | ||
5f0694b3 | 356 | dax_region = dev_dax->region; |
9557feee | 357 | if (dax_region->align > PUD_SIZE) { |
76202620 OH |
358 | dev_dbg(dev, "%s: alignment (%#x) > fault size (%#x)\n", |
359 | __func__, dax_region->align, fault_size); | |
9557feee DJ |
360 | return VM_FAULT_SIGBUS; |
361 | } | |
362 | ||
363 | /* dax pud mappings require pfn_t_devmap() */ | |
364 | if ((dax_region->pfn_flags & (PFN_DEV|PFN_MAP)) != (PFN_DEV|PFN_MAP)) { | |
76202620 | 365 | dev_dbg(dev, "%s: region lacks devmap flags\n", __func__); |
9557feee DJ |
366 | return VM_FAULT_SIGBUS; |
367 | } | |
368 | ||
70b085b0 DJ |
369 | if (fault_size < dax_region->align) |
370 | return VM_FAULT_SIGBUS; | |
371 | else if (fault_size > dax_region->align) | |
372 | return VM_FAULT_FALLBACK; | |
373 | ||
374 | /* if we are outside of the VMA */ | |
375 | if (pud_addr < vmf->vma->vm_start || | |
376 | (pud_addr + PUD_SIZE) > vmf->vma->vm_end) | |
377 | return VM_FAULT_SIGBUS; | |
378 | ||
9557feee | 379 | pgoff = linear_page_index(vmf->vma, pud_addr); |
73616367 | 380 | phys = dax_pgoff_to_phys(dev_dax, pgoff, PUD_SIZE); |
9557feee | 381 | if (phys == -1) { |
52084f89 | 382 | dev_dbg(dev, "%s: pgoff_to_phys(%#lx) failed\n", __func__, |
9557feee DJ |
383 | pgoff); |
384 | return VM_FAULT_SIGBUS; | |
385 | } | |
386 | ||
387 | pfn = phys_to_pfn_t(phys, dax_region->pfn_flags); | |
388 | ||
389 | return vmf_insert_pfn_pud(vmf->vma, vmf->address, vmf->pud, pfn, | |
390 | vmf->flags & FAULT_FLAG_WRITE); | |
391 | } | |
392 | #else | |
5f0694b3 | 393 | static int __dev_dax_pud_fault(struct dev_dax *dev_dax, struct vm_fault *vmf) |
9557feee DJ |
394 | { |
395 | return VM_FAULT_FALLBACK; | |
396 | } | |
397 | #endif /* !CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */ | |
398 | ||
5f0694b3 | 399 | static int dev_dax_huge_fault(struct vm_fault *vmf, |
c791ace1 | 400 | enum page_entry_size pe_size) |
dee41079 | 401 | { |
956a4cd2 | 402 | int rc, id; |
f4200391 | 403 | struct file *filp = vmf->vma->vm_file; |
5f0694b3 | 404 | struct dev_dax *dev_dax = filp->private_data; |
dee41079 | 405 | |
5f0694b3 | 406 | dev_dbg(&dev_dax->dev, "%s: %s: %s (%#lx - %#lx) size = %d\n", __func__, |
d8a849e1 | 407 | current->comm, (vmf->flags & FAULT_FLAG_WRITE) |
f4200391 | 408 | ? "write" : "read", |
76202620 | 409 | vmf->vma->vm_start, vmf->vma->vm_end, pe_size); |
dee41079 | 410 | |
7b6be844 | 411 | id = dax_read_lock(); |
c791ace1 DJ |
412 | switch (pe_size) { |
413 | case PE_SIZE_PTE: | |
5f0694b3 | 414 | rc = __dev_dax_pte_fault(dev_dax, vmf); |
a2d58167 | 415 | break; |
c791ace1 | 416 | case PE_SIZE_PMD: |
5f0694b3 | 417 | rc = __dev_dax_pmd_fault(dev_dax, vmf); |
9557feee | 418 | break; |
c791ace1 | 419 | case PE_SIZE_PUD: |
5f0694b3 | 420 | rc = __dev_dax_pud_fault(dev_dax, vmf); |
a2d58167 DJ |
421 | break; |
422 | default: | |
54eafcc9 | 423 | rc = VM_FAULT_SIGBUS; |
a2d58167 | 424 | } |
7b6be844 | 425 | dax_read_unlock(id); |
dee41079 DW |
426 | |
427 | return rc; | |
428 | } | |
429 | ||
5f0694b3 | 430 | static int dev_dax_fault(struct vm_fault *vmf) |
c791ace1 | 431 | { |
5f0694b3 | 432 | return dev_dax_huge_fault(vmf, PE_SIZE_PTE); |
c791ace1 DJ |
433 | } |
434 | ||
61586a22 DW |
435 | static int dev_dax_split(struct vm_area_struct *vma, unsigned long addr) |
436 | { | |
437 | struct file *filp = vma->vm_file; | |
438 | struct dev_dax *dev_dax = filp->private_data; | |
439 | struct dax_region *dax_region = dev_dax->region; | |
440 | ||
441 | if (!IS_ALIGNED(addr, dax_region->align)) | |
442 | return -EINVAL; | |
443 | return 0; | |
444 | } | |
445 | ||
5f0694b3 DW |
446 | static const struct vm_operations_struct dax_vm_ops = { |
447 | .fault = dev_dax_fault, | |
448 | .huge_fault = dev_dax_huge_fault, | |
61586a22 | 449 | .split = dev_dax_split, |
dee41079 DW |
450 | }; |
451 | ||
af69f51e | 452 | static int dax_mmap(struct file *filp, struct vm_area_struct *vma) |
dee41079 | 453 | { |
5f0694b3 | 454 | struct dev_dax *dev_dax = filp->private_data; |
7b6be844 | 455 | int rc, id; |
dee41079 | 456 | |
5f0694b3 | 457 | dev_dbg(&dev_dax->dev, "%s\n", __func__); |
dee41079 | 458 | |
7b6be844 DW |
459 | /* |
460 | * We lock to check dax_dev liveness and will re-check at | |
461 | * fault time. | |
462 | */ | |
463 | id = dax_read_lock(); | |
5f0694b3 | 464 | rc = check_vma(dev_dax, vma, __func__); |
7b6be844 | 465 | dax_read_unlock(id); |
dee41079 DW |
466 | if (rc) |
467 | return rc; | |
468 | ||
5f0694b3 | 469 | vma->vm_ops = &dax_vm_ops; |
dee41079 DW |
470 | vma->vm_flags |= VM_MIXEDMAP | VM_HUGEPAGE; |
471 | return 0; | |
043a9255 DW |
472 | } |
473 | ||
474 | /* return an unmapped area aligned to the dax region specified alignment */ | |
af69f51e | 475 | static unsigned long dax_get_unmapped_area(struct file *filp, |
043a9255 DW |
476 | unsigned long addr, unsigned long len, unsigned long pgoff, |
477 | unsigned long flags) | |
478 | { | |
479 | unsigned long off, off_end, off_align, len_align, addr_align, align; | |
5f0694b3 | 480 | struct dev_dax *dev_dax = filp ? filp->private_data : NULL; |
043a9255 DW |
481 | struct dax_region *dax_region; |
482 | ||
5f0694b3 | 483 | if (!dev_dax || addr) |
043a9255 DW |
484 | goto out; |
485 | ||
5f0694b3 | 486 | dax_region = dev_dax->region; |
043a9255 DW |
487 | align = dax_region->align; |
488 | off = pgoff << PAGE_SHIFT; | |
489 | off_end = off + len; | |
490 | off_align = round_up(off, align); | |
491 | ||
492 | if ((off_end <= off_align) || ((off_end - off_align) < align)) | |
493 | goto out; | |
494 | ||
495 | len_align = len + align; | |
496 | if ((off + len_align) < off) | |
497 | goto out; | |
dee41079 | 498 | |
043a9255 DW |
499 | addr_align = current->mm->get_unmapped_area(filp, addr, len_align, |
500 | pgoff, flags); | |
501 | if (!IS_ERR_VALUE(addr_align)) { | |
502 | addr_align += (off - addr_align) & (align - 1); | |
503 | return addr_align; | |
504 | } | |
505 | out: | |
506 | return current->mm->get_unmapped_area(filp, addr, len, pgoff, flags); | |
507 | } | |
508 | ||
af69f51e | 509 | static int dax_open(struct inode *inode, struct file *filp) |
043a9255 | 510 | { |
7b6be844 DW |
511 | struct dax_device *dax_dev = inode_dax(inode); |
512 | struct inode *__dax_inode = dax_inode(dax_dev); | |
513 | struct dev_dax *dev_dax = dax_get_private(dax_dev); | |
043a9255 | 514 | |
5f0694b3 | 515 | dev_dbg(&dev_dax->dev, "%s\n", __func__); |
7b6be844 DW |
516 | inode->i_mapping = __dax_inode->i_mapping; |
517 | inode->i_mapping->host = __dax_inode; | |
3bc52c45 | 518 | filp->f_mapping = inode->i_mapping; |
5660e13d | 519 | filp->f_wb_err = filemap_sample_wb_err(filp->f_mapping); |
5f0694b3 | 520 | filp->private_data = dev_dax; |
ebd84d72 | 521 | inode->i_flags = S_DAX; |
043a9255 | 522 | |
043a9255 DW |
523 | return 0; |
524 | } | |
dee41079 | 525 | |
af69f51e | 526 | static int dax_release(struct inode *inode, struct file *filp) |
043a9255 | 527 | { |
5f0694b3 | 528 | struct dev_dax *dev_dax = filp->private_data; |
043a9255 | 529 | |
5f0694b3 | 530 | dev_dbg(&dev_dax->dev, "%s\n", __func__); |
043a9255 | 531 | return 0; |
dee41079 DW |
532 | } |
533 | ||
ab68f262 DW |
534 | static const struct file_operations dax_fops = { |
535 | .llseek = noop_llseek, | |
536 | .owner = THIS_MODULE, | |
af69f51e DW |
537 | .open = dax_open, |
538 | .release = dax_release, | |
539 | .get_unmapped_area = dax_get_unmapped_area, | |
540 | .mmap = dax_mmap, | |
ab68f262 DW |
541 | }; |
542 | ||
5f0694b3 | 543 | static void dev_dax_release(struct device *dev) |
043a9255 | 544 | { |
5f0694b3 DW |
545 | struct dev_dax *dev_dax = to_dev_dax(dev); |
546 | struct dax_region *dax_region = dev_dax->region; | |
7b6be844 | 547 | struct dax_device *dax_dev = dev_dax->dax_dev; |
043a9255 | 548 | |
bbb3be17 DW |
549 | if (dev_dax->id >= 0) |
550 | ida_simple_remove(&dax_region->ida, dev_dax->id); | |
ebd84d72 | 551 | dax_region_put(dax_region); |
7b6be844 | 552 | put_dax(dax_dev); |
5f0694b3 | 553 | kfree(dev_dax); |
ebd84d72 DW |
554 | } |
555 | ||
5f0694b3 | 556 | static void kill_dev_dax(struct dev_dax *dev_dax) |
ebd84d72 | 557 | { |
7b6be844 DW |
558 | struct dax_device *dax_dev = dev_dax->dax_dev; |
559 | struct inode *inode = dax_inode(dax_dev); | |
560 | ||
561 | kill_dax(dax_dev); | |
562 | unmap_mapping_range(inode->i_mapping, 0, 0, 1); | |
ebd84d72 DW |
563 | } |
564 | ||
5f0694b3 | 565 | static void unregister_dev_dax(void *dev) |
ebd84d72 | 566 | { |
5f0694b3 | 567 | struct dev_dax *dev_dax = to_dev_dax(dev); |
7b6be844 DW |
568 | struct dax_device *dax_dev = dev_dax->dax_dev; |
569 | struct inode *inode = dax_inode(dax_dev); | |
570 | struct cdev *cdev = inode->i_cdev; | |
ebd84d72 | 571 | |
043a9255 DW |
572 | dev_dbg(dev, "%s\n", __func__); |
573 | ||
5f0694b3 | 574 | kill_dev_dax(dev_dax); |
7b6be844 | 575 | cdev_device_del(cdev, dev); |
92a3fa07 | 576 | put_device(dev); |
043a9255 DW |
577 | } |
578 | ||
5f0694b3 | 579 | struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, |
bbb3be17 | 580 | int id, struct resource *res, int count) |
043a9255 DW |
581 | { |
582 | struct device *parent = dax_region->dev; | |
7b6be844 | 583 | struct dax_device *dax_dev; |
5f0694b3 | 584 | struct dev_dax *dev_dax; |
7b6be844 | 585 | struct inode *inode; |
043a9255 | 586 | struct device *dev; |
ba09c01d | 587 | struct cdev *cdev; |
43fe51e1 DW |
588 | int rc, i; |
589 | ||
590 | if (!count) | |
591 | return ERR_PTR(-EINVAL); | |
043a9255 | 592 | |
5f0694b3 DW |
593 | dev_dax = kzalloc(sizeof(*dev_dax) + sizeof(*res) * count, GFP_KERNEL); |
594 | if (!dev_dax) | |
d76911ee | 595 | return ERR_PTR(-ENOMEM); |
043a9255 | 596 | |
9d2d01a0 DW |
597 | for (i = 0; i < count; i++) { |
598 | if (!IS_ALIGNED(res[i].start, dax_region->align) | |
599 | || !IS_ALIGNED(resource_size(&res[i]), | |
600 | dax_region->align)) { | |
601 | rc = -EINVAL; | |
602 | break; | |
603 | } | |
5f0694b3 DW |
604 | dev_dax->res[i].start = res[i].start; |
605 | dev_dax->res[i].end = res[i].end; | |
9d2d01a0 DW |
606 | } |
607 | ||
608 | if (i < count) | |
609 | goto err_id; | |
610 | ||
bbb3be17 DW |
611 | if (id < 0) { |
612 | id = ida_simple_get(&dax_region->ida, 0, 0, GFP_KERNEL); | |
613 | dev_dax->id = id; | |
614 | if (id < 0) { | |
615 | rc = id; | |
616 | goto err_id; | |
617 | } | |
618 | } else { | |
619 | /* region provider owns @id lifetime */ | |
620 | dev_dax->id = -1; | |
043a9255 DW |
621 | } |
622 | ||
6568b08b DW |
623 | /* |
624 | * No 'host' or dax_operations since there is no access to this | |
625 | * device outside of mmap of the resulting character device. | |
626 | */ | |
627 | dax_dev = alloc_dax(dev_dax, NULL, NULL); | |
43fe51e1 DW |
628 | if (!dax_dev) { |
629 | rc = -ENOMEM; | |
7b6be844 | 630 | goto err_dax; |
43fe51e1 | 631 | } |
3bc52c45 | 632 | |
7b6be844 | 633 | /* from here on we're committed to teardown via dax_dev_release() */ |
5f0694b3 | 634 | dev = &dev_dax->dev; |
ebd84d72 | 635 | device_initialize(dev); |
ba09c01d | 636 | |
7b6be844 DW |
637 | inode = dax_inode(dax_dev); |
638 | cdev = inode->i_cdev; | |
ba09c01d DW |
639 | cdev_init(cdev, &dax_fops); |
640 | cdev->owner = parent->driver->owner; | |
ba09c01d | 641 | |
5f0694b3 | 642 | dev_dax->num_resources = count; |
7b6be844 | 643 | dev_dax->dax_dev = dax_dev; |
5f0694b3 | 644 | dev_dax->region = dax_region; |
ba09c01d DW |
645 | kref_get(&dax_region->kref); |
646 | ||
7b6be844 | 647 | dev->devt = inode->i_rdev; |
ebd84d72 DW |
648 | dev->class = dax_class; |
649 | dev->parent = parent; | |
650 | dev->groups = dax_attribute_groups; | |
5f0694b3 | 651 | dev->release = dev_dax_release; |
bbb3be17 | 652 | dev_set_name(dev, "dax%d.%d", dax_region->id, id); |
92a3fa07 LG |
653 | |
654 | rc = cdev_device_add(cdev, dev); | |
ebd84d72 | 655 | if (rc) { |
5f0694b3 | 656 | kill_dev_dax(dev_dax); |
ebd84d72 | 657 | put_device(dev); |
d76911ee | 658 | return ERR_PTR(rc); |
ebd84d72 | 659 | } |
043a9255 | 660 | |
5f0694b3 | 661 | rc = devm_add_action_or_reset(dax_region->dev, unregister_dev_dax, dev); |
d76911ee DW |
662 | if (rc) |
663 | return ERR_PTR(rc); | |
664 | ||
5f0694b3 | 665 | return dev_dax; |
043a9255 | 666 | |
7b6be844 | 667 | err_dax: |
bbb3be17 DW |
668 | if (dev_dax->id >= 0) |
669 | ida_simple_remove(&dax_region->ida, dev_dax->id); | |
043a9255 | 670 | err_id: |
5f0694b3 | 671 | kfree(dev_dax); |
043a9255 | 672 | |
d76911ee | 673 | return ERR_PTR(rc); |
043a9255 | 674 | } |
5f0694b3 | 675 | EXPORT_SYMBOL_GPL(devm_create_dev_dax); |
043a9255 | 676 | |
ab68f262 DW |
677 | static int __init dax_init(void) |
678 | { | |
ab68f262 | 679 | dax_class = class_create(THIS_MODULE, "dax"); |
7b6be844 | 680 | return PTR_ERR_OR_ZERO(dax_class); |
ab68f262 DW |
681 | } |
682 | ||
683 | static void __exit dax_exit(void) | |
684 | { | |
685 | class_destroy(dax_class); | |
ab68f262 DW |
686 | } |
687 | ||
688 | MODULE_AUTHOR("Intel Corporation"); | |
689 | MODULE_LICENSE("GPL v2"); | |
690 | subsys_initcall(dax_init); | |
691 | module_exit(dax_exit); |