Commit | Line | Data |
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f8de50eb | 1 | /* |
a15a519e | 2 | * Copyright © 2006-2009, Intel Corporation. |
f8de50eb | 3 | * |
a15a519e DW |
4 | * This program is free software; you can redistribute it and/or modify it |
5 | * under the terms and conditions of the GNU General Public License, | |
6 | * version 2, as published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope it will be useful, but WITHOUT | |
9 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
10 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
11 | * more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public License along with | |
14 | * this program; if not, write to the Free Software Foundation, Inc., 59 Temple | |
15 | * Place - Suite 330, Boston, MA 02111-1307 USA. | |
f8de50eb | 16 | * |
98bcef56 | 17 | * Author: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> |
f8de50eb KA |
18 | */ |
19 | ||
38717946 | 20 | #include <linux/iova.h> |
15bbdec3 | 21 | #include <linux/module.h> |
85b45456 | 22 | #include <linux/slab.h> |
9257b4a2 OP |
23 | #include <linux/smp.h> |
24 | #include <linux/bitops.h> | |
25 | ||
26 | static bool iova_rcache_insert(struct iova_domain *iovad, | |
27 | unsigned long pfn, | |
28 | unsigned long size); | |
29 | static unsigned long iova_rcache_get(struct iova_domain *iovad, | |
30 | unsigned long size, | |
31 | unsigned long limit_pfn); | |
32 | static void init_iova_rcaches(struct iova_domain *iovad); | |
33 | static void free_iova_rcaches(struct iova_domain *iovad); | |
85b45456 | 34 | |
f8de50eb | 35 | void |
0fb5fe87 RM |
36 | init_iova_domain(struct iova_domain *iovad, unsigned long granule, |
37 | unsigned long start_pfn, unsigned long pfn_32bit) | |
f8de50eb | 38 | { |
0fb5fe87 RM |
39 | /* |
40 | * IOVA granularity will normally be equal to the smallest | |
41 | * supported IOMMU page size; both *must* be capable of | |
42 | * representing individual CPU pages exactly. | |
43 | */ | |
44 | BUG_ON((granule > PAGE_SIZE) || !is_power_of_2(granule)); | |
45 | ||
f8de50eb KA |
46 | spin_lock_init(&iovad->iova_rbtree_lock); |
47 | iovad->rbroot = RB_ROOT; | |
48 | iovad->cached32_node = NULL; | |
0fb5fe87 | 49 | iovad->granule = granule; |
1b722500 | 50 | iovad->start_pfn = start_pfn; |
f661197e | 51 | iovad->dma_32bit_pfn = pfn_32bit; |
9257b4a2 | 52 | init_iova_rcaches(iovad); |
f8de50eb | 53 | } |
9b41760b | 54 | EXPORT_SYMBOL_GPL(init_iova_domain); |
f8de50eb KA |
55 | |
56 | static struct rb_node * | |
57 | __get_cached_rbnode(struct iova_domain *iovad, unsigned long *limit_pfn) | |
58 | { | |
62280cf2 | 59 | if ((*limit_pfn > iovad->dma_32bit_pfn) || |
f8de50eb KA |
60 | (iovad->cached32_node == NULL)) |
61 | return rb_last(&iovad->rbroot); | |
62 | else { | |
63 | struct rb_node *prev_node = rb_prev(iovad->cached32_node); | |
64 | struct iova *curr_iova = | |
eba484b5 | 65 | rb_entry(iovad->cached32_node, struct iova, node); |
f8de50eb KA |
66 | *limit_pfn = curr_iova->pfn_lo - 1; |
67 | return prev_node; | |
68 | } | |
69 | } | |
70 | ||
71 | static void | |
72 | __cached_rbnode_insert_update(struct iova_domain *iovad, | |
73 | unsigned long limit_pfn, struct iova *new) | |
74 | { | |
f661197e | 75 | if (limit_pfn != iovad->dma_32bit_pfn) |
f8de50eb KA |
76 | return; |
77 | iovad->cached32_node = &new->node; | |
78 | } | |
79 | ||
80 | static void | |
81 | __cached_rbnode_delete_update(struct iova_domain *iovad, struct iova *free) | |
82 | { | |
83 | struct iova *cached_iova; | |
84 | struct rb_node *curr; | |
85 | ||
86 | if (!iovad->cached32_node) | |
87 | return; | |
88 | curr = iovad->cached32_node; | |
eba484b5 | 89 | cached_iova = rb_entry(curr, struct iova, node); |
f8de50eb | 90 | |
1c9fc3d1 CW |
91 | if (free->pfn_lo >= cached_iova->pfn_lo) { |
92 | struct rb_node *node = rb_next(&free->node); | |
eba484b5 | 93 | struct iova *iova = rb_entry(node, struct iova, node); |
1c9fc3d1 CW |
94 | |
95 | /* only cache if it's below 32bit pfn */ | |
96 | if (node && iova->pfn_lo < iovad->dma_32bit_pfn) | |
97 | iovad->cached32_node = node; | |
98 | else | |
99 | iovad->cached32_node = NULL; | |
100 | } | |
f8de50eb KA |
101 | } |
102 | ||
d751751a MS |
103 | /* Insert the iova into domain rbtree by holding writer lock */ |
104 | static void | |
105 | iova_insert_rbtree(struct rb_root *root, struct iova *iova, | |
106 | struct rb_node *start) | |
107 | { | |
108 | struct rb_node **new, *parent = NULL; | |
109 | ||
110 | new = (start) ? &start : &(root->rb_node); | |
111 | /* Figure out where to put new node */ | |
112 | while (*new) { | |
113 | struct iova *this = rb_entry(*new, struct iova, node); | |
114 | ||
115 | parent = *new; | |
116 | ||
117 | if (iova->pfn_lo < this->pfn_lo) | |
118 | new = &((*new)->rb_left); | |
119 | else if (iova->pfn_lo > this->pfn_lo) | |
120 | new = &((*new)->rb_right); | |
121 | else { | |
122 | WARN_ON(1); /* this should not happen */ | |
123 | return; | |
124 | } | |
125 | } | |
126 | /* Add new node and rebalance tree. */ | |
127 | rb_link_node(&iova->node, parent, new); | |
128 | rb_insert_color(&iova->node, root); | |
129 | } | |
130 | ||
8f6429c7 RM |
131 | /* |
132 | * Computes the padding size required, to make the start address | |
133 | * naturally aligned on the power-of-two order of its size | |
f76aec76 | 134 | */ |
8f6429c7 RM |
135 | static unsigned int |
136 | iova_get_pad_size(unsigned int size, unsigned int limit_pfn) | |
f76aec76 | 137 | { |
8f6429c7 | 138 | return (limit_pfn + 1 - size) & (__roundup_pow_of_two(size) - 1); |
f76aec76 KA |
139 | } |
140 | ||
ddf02886 | 141 | static int __alloc_and_insert_iova_range(struct iova_domain *iovad, |
142 | unsigned long size, unsigned long limit_pfn, | |
143 | struct iova *new, bool size_aligned) | |
f8de50eb | 144 | { |
ddf02886 | 145 | struct rb_node *prev, *curr = NULL; |
f8de50eb KA |
146 | unsigned long flags; |
147 | unsigned long saved_pfn; | |
f76aec76 | 148 | unsigned int pad_size = 0; |
f8de50eb KA |
149 | |
150 | /* Walk the tree backwards */ | |
151 | spin_lock_irqsave(&iovad->iova_rbtree_lock, flags); | |
152 | saved_pfn = limit_pfn; | |
153 | curr = __get_cached_rbnode(iovad, &limit_pfn); | |
ddf02886 | 154 | prev = curr; |
f8de50eb | 155 | while (curr) { |
eba484b5 | 156 | struct iova *curr_iova = rb_entry(curr, struct iova, node); |
ddf02886 | 157 | |
f8de50eb KA |
158 | if (limit_pfn < curr_iova->pfn_lo) |
159 | goto move_left; | |
f76aec76 | 160 | else if (limit_pfn < curr_iova->pfn_hi) |
f8de50eb | 161 | goto adjust_limit_pfn; |
f76aec76 KA |
162 | else { |
163 | if (size_aligned) | |
164 | pad_size = iova_get_pad_size(size, limit_pfn); | |
165 | if ((curr_iova->pfn_hi + size + pad_size) <= limit_pfn) | |
166 | break; /* found a free slot */ | |
167 | } | |
f8de50eb | 168 | adjust_limit_pfn: |
5016bdb7 | 169 | limit_pfn = curr_iova->pfn_lo ? (curr_iova->pfn_lo - 1) : 0; |
f8de50eb | 170 | move_left: |
ddf02886 | 171 | prev = curr; |
f8de50eb KA |
172 | curr = rb_prev(curr); |
173 | } | |
174 | ||
f76aec76 KA |
175 | if (!curr) { |
176 | if (size_aligned) | |
177 | pad_size = iova_get_pad_size(size, limit_pfn); | |
1b722500 | 178 | if ((iovad->start_pfn + size + pad_size) > limit_pfn) { |
f76aec76 KA |
179 | spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags); |
180 | return -ENOMEM; | |
181 | } | |
f8de50eb | 182 | } |
f76aec76 KA |
183 | |
184 | /* pfn_lo will point to size aligned address if size_aligned is set */ | |
185 | new->pfn_lo = limit_pfn - (size + pad_size) + 1; | |
186 | new->pfn_hi = new->pfn_lo + size - 1; | |
f8de50eb | 187 | |
d751751a MS |
188 | /* If we have 'prev', it's a valid place to start the insertion. */ |
189 | iova_insert_rbtree(&iovad->rbroot, new, prev); | |
ddf02886 | 190 | __cached_rbnode_insert_update(iovad, saved_pfn, new); |
191 | ||
f8de50eb | 192 | spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags); |
ddf02886 | 193 | |
194 | ||
f8de50eb KA |
195 | return 0; |
196 | } | |
197 | ||
ae1ff3d6 SA |
198 | static struct kmem_cache *iova_cache; |
199 | static unsigned int iova_cache_users; | |
200 | static DEFINE_MUTEX(iova_cache_mutex); | |
201 | ||
202 | struct iova *alloc_iova_mem(void) | |
203 | { | |
204 | return kmem_cache_alloc(iova_cache, GFP_ATOMIC); | |
205 | } | |
206 | EXPORT_SYMBOL(alloc_iova_mem); | |
207 | ||
208 | void free_iova_mem(struct iova *iova) | |
209 | { | |
210 | kmem_cache_free(iova_cache, iova); | |
211 | } | |
212 | EXPORT_SYMBOL(free_iova_mem); | |
213 | ||
214 | int iova_cache_get(void) | |
215 | { | |
216 | mutex_lock(&iova_cache_mutex); | |
217 | if (!iova_cache_users) { | |
218 | iova_cache = kmem_cache_create( | |
219 | "iommu_iova", sizeof(struct iova), 0, | |
220 | SLAB_HWCACHE_ALIGN, NULL); | |
221 | if (!iova_cache) { | |
222 | mutex_unlock(&iova_cache_mutex); | |
223 | printk(KERN_ERR "Couldn't create iova cache\n"); | |
224 | return -ENOMEM; | |
225 | } | |
226 | } | |
227 | ||
228 | iova_cache_users++; | |
229 | mutex_unlock(&iova_cache_mutex); | |
230 | ||
231 | return 0; | |
232 | } | |
9b41760b | 233 | EXPORT_SYMBOL_GPL(iova_cache_get); |
ae1ff3d6 SA |
234 | |
235 | void iova_cache_put(void) | |
236 | { | |
237 | mutex_lock(&iova_cache_mutex); | |
238 | if (WARN_ON(!iova_cache_users)) { | |
239 | mutex_unlock(&iova_cache_mutex); | |
240 | return; | |
241 | } | |
242 | iova_cache_users--; | |
243 | if (!iova_cache_users) | |
244 | kmem_cache_destroy(iova_cache); | |
245 | mutex_unlock(&iova_cache_mutex); | |
246 | } | |
9b41760b | 247 | EXPORT_SYMBOL_GPL(iova_cache_put); |
ae1ff3d6 | 248 | |
f8de50eb KA |
249 | /** |
250 | * alloc_iova - allocates an iova | |
07db0409 MI |
251 | * @iovad: - iova domain in question |
252 | * @size: - size of page frames to allocate | |
253 | * @limit_pfn: - max limit address | |
254 | * @size_aligned: - set if size_aligned address range is required | |
1b722500 RM |
255 | * This function allocates an iova in the range iovad->start_pfn to limit_pfn, |
256 | * searching top-down from limit_pfn to iovad->start_pfn. If the size_aligned | |
f76aec76 KA |
257 | * flag is set then the allocated address iova->pfn_lo will be naturally |
258 | * aligned on roundup_power_of_two(size). | |
f8de50eb KA |
259 | */ |
260 | struct iova * | |
261 | alloc_iova(struct iova_domain *iovad, unsigned long size, | |
f76aec76 KA |
262 | unsigned long limit_pfn, |
263 | bool size_aligned) | |
f8de50eb | 264 | { |
f8de50eb KA |
265 | struct iova *new_iova; |
266 | int ret; | |
267 | ||
268 | new_iova = alloc_iova_mem(); | |
269 | if (!new_iova) | |
270 | return NULL; | |
271 | ||
ddf02886 | 272 | ret = __alloc_and_insert_iova_range(iovad, size, limit_pfn, |
273 | new_iova, size_aligned); | |
f8de50eb KA |
274 | |
275 | if (ret) { | |
f8de50eb KA |
276 | free_iova_mem(new_iova); |
277 | return NULL; | |
278 | } | |
279 | ||
f8de50eb KA |
280 | return new_iova; |
281 | } | |
9b41760b | 282 | EXPORT_SYMBOL_GPL(alloc_iova); |
f8de50eb | 283 | |
9257b4a2 OP |
284 | static struct iova * |
285 | private_find_iova(struct iova_domain *iovad, unsigned long pfn) | |
f8de50eb | 286 | { |
9257b4a2 OP |
287 | struct rb_node *node = iovad->rbroot.rb_node; |
288 | ||
289 | assert_spin_locked(&iovad->iova_rbtree_lock); | |
f8de50eb | 290 | |
f8de50eb | 291 | while (node) { |
eba484b5 | 292 | struct iova *iova = rb_entry(node, struct iova, node); |
f8de50eb KA |
293 | |
294 | /* If pfn falls within iova's range, return iova */ | |
295 | if ((pfn >= iova->pfn_lo) && (pfn <= iova->pfn_hi)) { | |
f8de50eb KA |
296 | return iova; |
297 | } | |
298 | ||
299 | if (pfn < iova->pfn_lo) | |
300 | node = node->rb_left; | |
301 | else if (pfn > iova->pfn_lo) | |
302 | node = node->rb_right; | |
303 | } | |
304 | ||
f8de50eb KA |
305 | return NULL; |
306 | } | |
9257b4a2 OP |
307 | |
308 | static void private_free_iova(struct iova_domain *iovad, struct iova *iova) | |
309 | { | |
310 | assert_spin_locked(&iovad->iova_rbtree_lock); | |
311 | __cached_rbnode_delete_update(iovad, iova); | |
312 | rb_erase(&iova->node, &iovad->rbroot); | |
313 | free_iova_mem(iova); | |
314 | } | |
315 | ||
316 | /** | |
317 | * find_iova - finds an iova for a given pfn | |
318 | * @iovad: - iova domain in question. | |
319 | * @pfn: - page frame number | |
320 | * This function finds and returns an iova belonging to the | |
321 | * given doamin which matches the given pfn. | |
322 | */ | |
323 | struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn) | |
324 | { | |
325 | unsigned long flags; | |
326 | struct iova *iova; | |
327 | ||
328 | /* Take the lock so that no other thread is manipulating the rbtree */ | |
329 | spin_lock_irqsave(&iovad->iova_rbtree_lock, flags); | |
330 | iova = private_find_iova(iovad, pfn); | |
331 | spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags); | |
332 | return iova; | |
333 | } | |
9b41760b | 334 | EXPORT_SYMBOL_GPL(find_iova); |
f8de50eb KA |
335 | |
336 | /** | |
337 | * __free_iova - frees the given iova | |
338 | * @iovad: iova domain in question. | |
339 | * @iova: iova in question. | |
340 | * Frees the given iova belonging to the giving domain | |
341 | */ | |
342 | void | |
343 | __free_iova(struct iova_domain *iovad, struct iova *iova) | |
344 | { | |
345 | unsigned long flags; | |
346 | ||
347 | spin_lock_irqsave(&iovad->iova_rbtree_lock, flags); | |
9257b4a2 | 348 | private_free_iova(iovad, iova); |
f8de50eb | 349 | spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags); |
f8de50eb | 350 | } |
9b41760b | 351 | EXPORT_SYMBOL_GPL(__free_iova); |
f8de50eb KA |
352 | |
353 | /** | |
354 | * free_iova - finds and frees the iova for a given pfn | |
355 | * @iovad: - iova domain in question. | |
356 | * @pfn: - pfn that is allocated previously | |
357 | * This functions finds an iova for a given pfn and then | |
358 | * frees the iova from that domain. | |
359 | */ | |
360 | void | |
361 | free_iova(struct iova_domain *iovad, unsigned long pfn) | |
362 | { | |
363 | struct iova *iova = find_iova(iovad, pfn); | |
733cac2a | 364 | |
f8de50eb KA |
365 | if (iova) |
366 | __free_iova(iovad, iova); | |
367 | ||
368 | } | |
9b41760b | 369 | EXPORT_SYMBOL_GPL(free_iova); |
f8de50eb | 370 | |
9257b4a2 OP |
371 | /** |
372 | * alloc_iova_fast - allocates an iova from rcache | |
373 | * @iovad: - iova domain in question | |
374 | * @size: - size of page frames to allocate | |
375 | * @limit_pfn: - max limit address | |
376 | * This function tries to satisfy an iova allocation from the rcache, | |
377 | * and falls back to regular allocation on failure. | |
378 | */ | |
379 | unsigned long | |
380 | alloc_iova_fast(struct iova_domain *iovad, unsigned long size, | |
381 | unsigned long limit_pfn) | |
382 | { | |
383 | bool flushed_rcache = false; | |
384 | unsigned long iova_pfn; | |
385 | struct iova *new_iova; | |
386 | ||
387 | iova_pfn = iova_rcache_get(iovad, size, limit_pfn); | |
388 | if (iova_pfn) | |
389 | return iova_pfn; | |
390 | ||
391 | retry: | |
392 | new_iova = alloc_iova(iovad, size, limit_pfn, true); | |
393 | if (!new_iova) { | |
394 | unsigned int cpu; | |
395 | ||
396 | if (flushed_rcache) | |
397 | return 0; | |
398 | ||
399 | /* Try replenishing IOVAs by flushing rcache. */ | |
400 | flushed_rcache = true; | |
583248e6 | 401 | preempt_disable(); |
9257b4a2 OP |
402 | for_each_online_cpu(cpu) |
403 | free_cpu_cached_iovas(cpu, iovad); | |
583248e6 | 404 | preempt_enable(); |
9257b4a2 OP |
405 | goto retry; |
406 | } | |
407 | ||
408 | return new_iova->pfn_lo; | |
409 | } | |
410 | EXPORT_SYMBOL_GPL(alloc_iova_fast); | |
411 | ||
412 | /** | |
413 | * free_iova_fast - free iova pfn range into rcache | |
414 | * @iovad: - iova domain in question. | |
415 | * @pfn: - pfn that is allocated previously | |
416 | * @size: - # of pages in range | |
417 | * This functions frees an iova range by trying to put it into the rcache, | |
418 | * falling back to regular iova deallocation via free_iova() if this fails. | |
419 | */ | |
420 | void | |
421 | free_iova_fast(struct iova_domain *iovad, unsigned long pfn, unsigned long size) | |
422 | { | |
423 | if (iova_rcache_insert(iovad, pfn, size)) | |
424 | return; | |
425 | ||
426 | free_iova(iovad, pfn); | |
427 | } | |
428 | EXPORT_SYMBOL_GPL(free_iova_fast); | |
429 | ||
f8de50eb KA |
430 | /** |
431 | * put_iova_domain - destroys the iova doamin | |
432 | * @iovad: - iova domain in question. | |
433 | * All the iova's in that domain are destroyed. | |
434 | */ | |
435 | void put_iova_domain(struct iova_domain *iovad) | |
436 | { | |
437 | struct rb_node *node; | |
438 | unsigned long flags; | |
439 | ||
9257b4a2 | 440 | free_iova_rcaches(iovad); |
f8de50eb KA |
441 | spin_lock_irqsave(&iovad->iova_rbtree_lock, flags); |
442 | node = rb_first(&iovad->rbroot); | |
443 | while (node) { | |
eba484b5 | 444 | struct iova *iova = rb_entry(node, struct iova, node); |
733cac2a | 445 | |
f8de50eb KA |
446 | rb_erase(node, &iovad->rbroot); |
447 | free_iova_mem(iova); | |
448 | node = rb_first(&iovad->rbroot); | |
449 | } | |
450 | spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags); | |
451 | } | |
9b41760b | 452 | EXPORT_SYMBOL_GPL(put_iova_domain); |
f8de50eb KA |
453 | |
454 | static int | |
455 | __is_range_overlap(struct rb_node *node, | |
456 | unsigned long pfn_lo, unsigned long pfn_hi) | |
457 | { | |
eba484b5 | 458 | struct iova *iova = rb_entry(node, struct iova, node); |
f8de50eb KA |
459 | |
460 | if ((pfn_lo <= iova->pfn_hi) && (pfn_hi >= iova->pfn_lo)) | |
461 | return 1; | |
462 | return 0; | |
463 | } | |
464 | ||
75f05569 JL |
465 | static inline struct iova * |
466 | alloc_and_init_iova(unsigned long pfn_lo, unsigned long pfn_hi) | |
467 | { | |
468 | struct iova *iova; | |
469 | ||
470 | iova = alloc_iova_mem(); | |
471 | if (iova) { | |
472 | iova->pfn_lo = pfn_lo; | |
473 | iova->pfn_hi = pfn_hi; | |
474 | } | |
475 | ||
476 | return iova; | |
477 | } | |
478 | ||
f8de50eb KA |
479 | static struct iova * |
480 | __insert_new_range(struct iova_domain *iovad, | |
481 | unsigned long pfn_lo, unsigned long pfn_hi) | |
482 | { | |
483 | struct iova *iova; | |
484 | ||
75f05569 JL |
485 | iova = alloc_and_init_iova(pfn_lo, pfn_hi); |
486 | if (iova) | |
d751751a | 487 | iova_insert_rbtree(&iovad->rbroot, iova, NULL); |
f8de50eb | 488 | |
f8de50eb KA |
489 | return iova; |
490 | } | |
491 | ||
492 | static void | |
493 | __adjust_overlap_range(struct iova *iova, | |
494 | unsigned long *pfn_lo, unsigned long *pfn_hi) | |
495 | { | |
496 | if (*pfn_lo < iova->pfn_lo) | |
497 | iova->pfn_lo = *pfn_lo; | |
498 | if (*pfn_hi > iova->pfn_hi) | |
499 | *pfn_lo = iova->pfn_hi + 1; | |
500 | } | |
501 | ||
502 | /** | |
503 | * reserve_iova - reserves an iova in the given range | |
504 | * @iovad: - iova domain pointer | |
505 | * @pfn_lo: - lower page frame address | |
506 | * @pfn_hi:- higher pfn adderss | |
507 | * This function allocates reserves the address range from pfn_lo to pfn_hi so | |
508 | * that this address is not dished out as part of alloc_iova. | |
509 | */ | |
510 | struct iova * | |
511 | reserve_iova(struct iova_domain *iovad, | |
512 | unsigned long pfn_lo, unsigned long pfn_hi) | |
513 | { | |
514 | struct rb_node *node; | |
515 | unsigned long flags; | |
516 | struct iova *iova; | |
517 | unsigned int overlap = 0; | |
518 | ||
3d39cecc | 519 | spin_lock_irqsave(&iovad->iova_rbtree_lock, flags); |
f8de50eb KA |
520 | for (node = rb_first(&iovad->rbroot); node; node = rb_next(node)) { |
521 | if (__is_range_overlap(node, pfn_lo, pfn_hi)) { | |
eba484b5 | 522 | iova = rb_entry(node, struct iova, node); |
f8de50eb KA |
523 | __adjust_overlap_range(iova, &pfn_lo, &pfn_hi); |
524 | if ((pfn_lo >= iova->pfn_lo) && | |
525 | (pfn_hi <= iova->pfn_hi)) | |
526 | goto finish; | |
527 | overlap = 1; | |
528 | ||
529 | } else if (overlap) | |
530 | break; | |
531 | } | |
532 | ||
25985edc | 533 | /* We are here either because this is the first reserver node |
f8de50eb KA |
534 | * or need to insert remaining non overlap addr range |
535 | */ | |
536 | iova = __insert_new_range(iovad, pfn_lo, pfn_hi); | |
537 | finish: | |
538 | ||
3d39cecc | 539 | spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags); |
f8de50eb KA |
540 | return iova; |
541 | } | |
9b41760b | 542 | EXPORT_SYMBOL_GPL(reserve_iova); |
f8de50eb KA |
543 | |
544 | /** | |
545 | * copy_reserved_iova - copies the reserved between domains | |
546 | * @from: - source doamin from where to copy | |
547 | * @to: - destination domin where to copy | |
548 | * This function copies reserved iova's from one doamin to | |
549 | * other. | |
550 | */ | |
551 | void | |
552 | copy_reserved_iova(struct iova_domain *from, struct iova_domain *to) | |
553 | { | |
554 | unsigned long flags; | |
555 | struct rb_node *node; | |
556 | ||
3d39cecc | 557 | spin_lock_irqsave(&from->iova_rbtree_lock, flags); |
f8de50eb | 558 | for (node = rb_first(&from->rbroot); node; node = rb_next(node)) { |
eba484b5 | 559 | struct iova *iova = rb_entry(node, struct iova, node); |
f8de50eb | 560 | struct iova *new_iova; |
733cac2a | 561 | |
f8de50eb KA |
562 | new_iova = reserve_iova(to, iova->pfn_lo, iova->pfn_hi); |
563 | if (!new_iova) | |
564 | printk(KERN_ERR "Reserve iova range %lx@%lx failed\n", | |
565 | iova->pfn_lo, iova->pfn_lo); | |
566 | } | |
3d39cecc | 567 | spin_unlock_irqrestore(&from->iova_rbtree_lock, flags); |
f8de50eb | 568 | } |
9b41760b | 569 | EXPORT_SYMBOL_GPL(copy_reserved_iova); |
75f05569 JL |
570 | |
571 | struct iova * | |
572 | split_and_remove_iova(struct iova_domain *iovad, struct iova *iova, | |
573 | unsigned long pfn_lo, unsigned long pfn_hi) | |
574 | { | |
575 | unsigned long flags; | |
576 | struct iova *prev = NULL, *next = NULL; | |
577 | ||
578 | spin_lock_irqsave(&iovad->iova_rbtree_lock, flags); | |
579 | if (iova->pfn_lo < pfn_lo) { | |
580 | prev = alloc_and_init_iova(iova->pfn_lo, pfn_lo - 1); | |
581 | if (prev == NULL) | |
582 | goto error; | |
583 | } | |
584 | if (iova->pfn_hi > pfn_hi) { | |
585 | next = alloc_and_init_iova(pfn_hi + 1, iova->pfn_hi); | |
586 | if (next == NULL) | |
587 | goto error; | |
588 | } | |
589 | ||
590 | __cached_rbnode_delete_update(iovad, iova); | |
591 | rb_erase(&iova->node, &iovad->rbroot); | |
592 | ||
593 | if (prev) { | |
d751751a | 594 | iova_insert_rbtree(&iovad->rbroot, prev, NULL); |
75f05569 JL |
595 | iova->pfn_lo = pfn_lo; |
596 | } | |
597 | if (next) { | |
d751751a | 598 | iova_insert_rbtree(&iovad->rbroot, next, NULL); |
75f05569 JL |
599 | iova->pfn_hi = pfn_hi; |
600 | } | |
601 | spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags); | |
602 | ||
603 | return iova; | |
604 | ||
605 | error: | |
606 | spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags); | |
607 | if (prev) | |
608 | free_iova_mem(prev); | |
609 | return NULL; | |
610 | } | |
15bbdec3 | 611 | |
9257b4a2 OP |
612 | /* |
613 | * Magazine caches for IOVA ranges. For an introduction to magazines, | |
614 | * see the USENIX 2001 paper "Magazines and Vmem: Extending the Slab | |
615 | * Allocator to Many CPUs and Arbitrary Resources" by Bonwick and Adams. | |
616 | * For simplicity, we use a static magazine size and don't implement the | |
617 | * dynamic size tuning described in the paper. | |
618 | */ | |
619 | ||
620 | #define IOVA_MAG_SIZE 128 | |
621 | ||
622 | struct iova_magazine { | |
623 | unsigned long size; | |
624 | unsigned long pfns[IOVA_MAG_SIZE]; | |
625 | }; | |
626 | ||
627 | struct iova_cpu_rcache { | |
628 | spinlock_t lock; | |
629 | struct iova_magazine *loaded; | |
630 | struct iova_magazine *prev; | |
631 | }; | |
632 | ||
633 | static struct iova_magazine *iova_magazine_alloc(gfp_t flags) | |
634 | { | |
635 | return kzalloc(sizeof(struct iova_magazine), flags); | |
636 | } | |
637 | ||
638 | static void iova_magazine_free(struct iova_magazine *mag) | |
639 | { | |
640 | kfree(mag); | |
641 | } | |
642 | ||
643 | static void | |
644 | iova_magazine_free_pfns(struct iova_magazine *mag, struct iova_domain *iovad) | |
645 | { | |
646 | unsigned long flags; | |
647 | int i; | |
648 | ||
649 | if (!mag) | |
650 | return; | |
651 | ||
652 | spin_lock_irqsave(&iovad->iova_rbtree_lock, flags); | |
653 | ||
654 | for (i = 0 ; i < mag->size; ++i) { | |
655 | struct iova *iova = private_find_iova(iovad, mag->pfns[i]); | |
656 | ||
657 | BUG_ON(!iova); | |
658 | private_free_iova(iovad, iova); | |
659 | } | |
660 | ||
661 | spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags); | |
662 | ||
663 | mag->size = 0; | |
664 | } | |
665 | ||
666 | static bool iova_magazine_full(struct iova_magazine *mag) | |
667 | { | |
668 | return (mag && mag->size == IOVA_MAG_SIZE); | |
669 | } | |
670 | ||
671 | static bool iova_magazine_empty(struct iova_magazine *mag) | |
672 | { | |
673 | return (!mag || mag->size == 0); | |
674 | } | |
675 | ||
676 | static unsigned long iova_magazine_pop(struct iova_magazine *mag, | |
677 | unsigned long limit_pfn) | |
678 | { | |
679 | BUG_ON(iova_magazine_empty(mag)); | |
680 | ||
681 | if (mag->pfns[mag->size - 1] >= limit_pfn) | |
682 | return 0; | |
683 | ||
684 | return mag->pfns[--mag->size]; | |
685 | } | |
686 | ||
687 | static void iova_magazine_push(struct iova_magazine *mag, unsigned long pfn) | |
688 | { | |
689 | BUG_ON(iova_magazine_full(mag)); | |
690 | ||
691 | mag->pfns[mag->size++] = pfn; | |
692 | } | |
693 | ||
694 | static void init_iova_rcaches(struct iova_domain *iovad) | |
695 | { | |
696 | struct iova_cpu_rcache *cpu_rcache; | |
697 | struct iova_rcache *rcache; | |
698 | unsigned int cpu; | |
699 | int i; | |
700 | ||
701 | for (i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) { | |
702 | rcache = &iovad->rcaches[i]; | |
703 | spin_lock_init(&rcache->lock); | |
704 | rcache->depot_size = 0; | |
705 | rcache->cpu_rcaches = __alloc_percpu(sizeof(*cpu_rcache), cache_line_size()); | |
706 | if (WARN_ON(!rcache->cpu_rcaches)) | |
707 | continue; | |
708 | for_each_possible_cpu(cpu) { | |
709 | cpu_rcache = per_cpu_ptr(rcache->cpu_rcaches, cpu); | |
710 | spin_lock_init(&cpu_rcache->lock); | |
711 | cpu_rcache->loaded = iova_magazine_alloc(GFP_KERNEL); | |
712 | cpu_rcache->prev = iova_magazine_alloc(GFP_KERNEL); | |
713 | } | |
714 | } | |
715 | } | |
716 | ||
717 | /* | |
718 | * Try inserting IOVA range starting with 'iova_pfn' into 'rcache', and | |
719 | * return true on success. Can fail if rcache is full and we can't free | |
720 | * space, and free_iova() (our only caller) will then return the IOVA | |
721 | * range to the rbtree instead. | |
722 | */ | |
723 | static bool __iova_rcache_insert(struct iova_domain *iovad, | |
724 | struct iova_rcache *rcache, | |
725 | unsigned long iova_pfn) | |
726 | { | |
727 | struct iova_magazine *mag_to_free = NULL; | |
728 | struct iova_cpu_rcache *cpu_rcache; | |
729 | bool can_insert = false; | |
730 | unsigned long flags; | |
731 | ||
583248e6 | 732 | cpu_rcache = get_cpu_ptr(rcache->cpu_rcaches); |
9257b4a2 OP |
733 | spin_lock_irqsave(&cpu_rcache->lock, flags); |
734 | ||
735 | if (!iova_magazine_full(cpu_rcache->loaded)) { | |
736 | can_insert = true; | |
737 | } else if (!iova_magazine_full(cpu_rcache->prev)) { | |
738 | swap(cpu_rcache->prev, cpu_rcache->loaded); | |
739 | can_insert = true; | |
740 | } else { | |
741 | struct iova_magazine *new_mag = iova_magazine_alloc(GFP_ATOMIC); | |
742 | ||
743 | if (new_mag) { | |
744 | spin_lock(&rcache->lock); | |
745 | if (rcache->depot_size < MAX_GLOBAL_MAGS) { | |
746 | rcache->depot[rcache->depot_size++] = | |
747 | cpu_rcache->loaded; | |
748 | } else { | |
749 | mag_to_free = cpu_rcache->loaded; | |
750 | } | |
751 | spin_unlock(&rcache->lock); | |
752 | ||
753 | cpu_rcache->loaded = new_mag; | |
754 | can_insert = true; | |
755 | } | |
756 | } | |
757 | ||
758 | if (can_insert) | |
759 | iova_magazine_push(cpu_rcache->loaded, iova_pfn); | |
760 | ||
761 | spin_unlock_irqrestore(&cpu_rcache->lock, flags); | |
583248e6 | 762 | put_cpu_ptr(rcache->cpu_rcaches); |
9257b4a2 OP |
763 | |
764 | if (mag_to_free) { | |
765 | iova_magazine_free_pfns(mag_to_free, iovad); | |
766 | iova_magazine_free(mag_to_free); | |
767 | } | |
768 | ||
769 | return can_insert; | |
770 | } | |
771 | ||
772 | static bool iova_rcache_insert(struct iova_domain *iovad, unsigned long pfn, | |
773 | unsigned long size) | |
774 | { | |
775 | unsigned int log_size = order_base_2(size); | |
776 | ||
777 | if (log_size >= IOVA_RANGE_CACHE_MAX_SIZE) | |
778 | return false; | |
779 | ||
780 | return __iova_rcache_insert(iovad, &iovad->rcaches[log_size], pfn); | |
781 | } | |
782 | ||
783 | /* | |
784 | * Caller wants to allocate a new IOVA range from 'rcache'. If we can | |
785 | * satisfy the request, return a matching non-NULL range and remove | |
786 | * it from the 'rcache'. | |
787 | */ | |
788 | static unsigned long __iova_rcache_get(struct iova_rcache *rcache, | |
789 | unsigned long limit_pfn) | |
790 | { | |
791 | struct iova_cpu_rcache *cpu_rcache; | |
792 | unsigned long iova_pfn = 0; | |
793 | bool has_pfn = false; | |
794 | unsigned long flags; | |
795 | ||
583248e6 | 796 | cpu_rcache = get_cpu_ptr(rcache->cpu_rcaches); |
9257b4a2 OP |
797 | spin_lock_irqsave(&cpu_rcache->lock, flags); |
798 | ||
799 | if (!iova_magazine_empty(cpu_rcache->loaded)) { | |
800 | has_pfn = true; | |
801 | } else if (!iova_magazine_empty(cpu_rcache->prev)) { | |
802 | swap(cpu_rcache->prev, cpu_rcache->loaded); | |
803 | has_pfn = true; | |
804 | } else { | |
805 | spin_lock(&rcache->lock); | |
806 | if (rcache->depot_size > 0) { | |
807 | iova_magazine_free(cpu_rcache->loaded); | |
808 | cpu_rcache->loaded = rcache->depot[--rcache->depot_size]; | |
809 | has_pfn = true; | |
810 | } | |
811 | spin_unlock(&rcache->lock); | |
812 | } | |
813 | ||
814 | if (has_pfn) | |
815 | iova_pfn = iova_magazine_pop(cpu_rcache->loaded, limit_pfn); | |
816 | ||
817 | spin_unlock_irqrestore(&cpu_rcache->lock, flags); | |
583248e6 | 818 | put_cpu_ptr(rcache->cpu_rcaches); |
9257b4a2 OP |
819 | |
820 | return iova_pfn; | |
821 | } | |
822 | ||
823 | /* | |
824 | * Try to satisfy IOVA allocation range from rcache. Fail if requested | |
825 | * size is too big or the DMA limit we are given isn't satisfied by the | |
826 | * top element in the magazine. | |
827 | */ | |
828 | static unsigned long iova_rcache_get(struct iova_domain *iovad, | |
829 | unsigned long size, | |
830 | unsigned long limit_pfn) | |
831 | { | |
832 | unsigned int log_size = order_base_2(size); | |
833 | ||
834 | if (log_size >= IOVA_RANGE_CACHE_MAX_SIZE) | |
835 | return 0; | |
836 | ||
837 | return __iova_rcache_get(&iovad->rcaches[log_size], limit_pfn); | |
838 | } | |
839 | ||
840 | /* | |
841 | * Free a cpu's rcache. | |
842 | */ | |
843 | static void free_cpu_iova_rcache(unsigned int cpu, struct iova_domain *iovad, | |
844 | struct iova_rcache *rcache) | |
845 | { | |
846 | struct iova_cpu_rcache *cpu_rcache = per_cpu_ptr(rcache->cpu_rcaches, cpu); | |
847 | unsigned long flags; | |
848 | ||
849 | spin_lock_irqsave(&cpu_rcache->lock, flags); | |
850 | ||
851 | iova_magazine_free_pfns(cpu_rcache->loaded, iovad); | |
852 | iova_magazine_free(cpu_rcache->loaded); | |
853 | ||
854 | iova_magazine_free_pfns(cpu_rcache->prev, iovad); | |
855 | iova_magazine_free(cpu_rcache->prev); | |
856 | ||
857 | spin_unlock_irqrestore(&cpu_rcache->lock, flags); | |
858 | } | |
859 | ||
860 | /* | |
861 | * free rcache data structures. | |
862 | */ | |
863 | static void free_iova_rcaches(struct iova_domain *iovad) | |
864 | { | |
865 | struct iova_rcache *rcache; | |
866 | unsigned long flags; | |
867 | unsigned int cpu; | |
868 | int i, j; | |
869 | ||
870 | for (i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) { | |
871 | rcache = &iovad->rcaches[i]; | |
872 | for_each_possible_cpu(cpu) | |
873 | free_cpu_iova_rcache(cpu, iovad, rcache); | |
874 | spin_lock_irqsave(&rcache->lock, flags); | |
875 | free_percpu(rcache->cpu_rcaches); | |
876 | for (j = 0; j < rcache->depot_size; ++j) { | |
877 | iova_magazine_free_pfns(rcache->depot[j], iovad); | |
878 | iova_magazine_free(rcache->depot[j]); | |
879 | } | |
880 | spin_unlock_irqrestore(&rcache->lock, flags); | |
881 | } | |
882 | } | |
883 | ||
884 | /* | |
885 | * free all the IOVA ranges cached by a cpu (used when cpu is unplugged) | |
886 | */ | |
887 | void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad) | |
888 | { | |
889 | struct iova_cpu_rcache *cpu_rcache; | |
890 | struct iova_rcache *rcache; | |
891 | unsigned long flags; | |
892 | int i; | |
893 | ||
894 | for (i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) { | |
895 | rcache = &iovad->rcaches[i]; | |
896 | cpu_rcache = per_cpu_ptr(rcache->cpu_rcaches, cpu); | |
897 | spin_lock_irqsave(&cpu_rcache->lock, flags); | |
898 | iova_magazine_free_pfns(cpu_rcache->loaded, iovad); | |
899 | iova_magazine_free_pfns(cpu_rcache->prev, iovad); | |
900 | spin_unlock_irqrestore(&cpu_rcache->lock, flags); | |
901 | } | |
902 | } | |
903 | ||
15bbdec3 SA |
904 | MODULE_AUTHOR("Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>"); |
905 | MODULE_LICENSE("GPL"); |