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1/*
2 * Copyright © 2006-2009, Intel Corporation.
3 *
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.
16 *
17 * Author: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
18 */
19
20#include <linux/iova.h>
21
22void
23init_iova_domain(struct iova_domain *iovad, unsigned long pfn_32bit)
24{
25 spin_lock_init(&iovad->iova_rbtree_lock);
26 iovad->rbroot = RB_ROOT;
27 iovad->cached32_node = NULL;
28 iovad->dma_32bit_pfn = pfn_32bit;
29}
30
31static struct rb_node *
32__get_cached_rbnode(struct iova_domain *iovad, unsigned long *limit_pfn)
33{
34 if ((*limit_pfn != iovad->dma_32bit_pfn) ||
35 (iovad->cached32_node == NULL))
36 return rb_last(&iovad->rbroot);
37 else {
38 struct rb_node *prev_node = rb_prev(iovad->cached32_node);
39 struct iova *curr_iova =
40 container_of(iovad->cached32_node, struct iova, node);
41 *limit_pfn = curr_iova->pfn_lo - 1;
42 return prev_node;
43 }
44}
45
46static void
47__cached_rbnode_insert_update(struct iova_domain *iovad,
48 unsigned long limit_pfn, struct iova *new)
49{
50 if (limit_pfn != iovad->dma_32bit_pfn)
51 return;
52 iovad->cached32_node = &new->node;
53}
54
55static void
56__cached_rbnode_delete_update(struct iova_domain *iovad, struct iova *free)
57{
58 struct iova *cached_iova;
59 struct rb_node *curr;
60
61 if (!iovad->cached32_node)
62 return;
63 curr = iovad->cached32_node;
64 cached_iova = container_of(curr, struct iova, node);
65
66 if (free->pfn_lo >= cached_iova->pfn_lo) {
67 struct rb_node *node = rb_next(&free->node);
68 struct iova *iova = container_of(node, struct iova, node);
69
70 /* only cache if it's below 32bit pfn */
71 if (node && iova->pfn_lo < iovad->dma_32bit_pfn)
72 iovad->cached32_node = node;
73 else
74 iovad->cached32_node = NULL;
75 }
76}
77
78/* Computes the padding size required, to make the
79 * the start address naturally aligned on its size
80 */
81static int
82iova_get_pad_size(int size, unsigned int limit_pfn)
83{
84 unsigned int pad_size = 0;
85 unsigned int order = ilog2(size);
86
87 if (order)
88 pad_size = (limit_pfn + 1) % (1 << order);
89
90 return pad_size;
91}
92
93static int __alloc_and_insert_iova_range(struct iova_domain *iovad,
94 unsigned long size, unsigned long limit_pfn,
95 struct iova *new, bool size_aligned)
96{
97 struct rb_node *prev, *curr = NULL;
98 unsigned long flags;
99 unsigned long saved_pfn;
100 unsigned int pad_size = 0;
101
102 /* Walk the tree backwards */
103 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
104 saved_pfn = limit_pfn;
105 curr = __get_cached_rbnode(iovad, &limit_pfn);
106 prev = curr;
107 while (curr) {
108 struct iova *curr_iova = container_of(curr, struct iova, node);
109
110 if (limit_pfn < curr_iova->pfn_lo)
111 goto move_left;
112 else if (limit_pfn < curr_iova->pfn_hi)
113 goto adjust_limit_pfn;
114 else {
115 if (size_aligned)
116 pad_size = iova_get_pad_size(size, limit_pfn);
117 if ((curr_iova->pfn_hi + size + pad_size) <= limit_pfn)
118 break; /* found a free slot */
119 }
120adjust_limit_pfn:
121 limit_pfn = curr_iova->pfn_lo - 1;
122move_left:
123 prev = curr;
124 curr = rb_prev(curr);
125 }
126
127 if (!curr) {
128 if (size_aligned)
129 pad_size = iova_get_pad_size(size, limit_pfn);
130 if ((IOVA_START_PFN + size + pad_size) > limit_pfn) {
131 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
132 return -ENOMEM;
133 }
134 }
135
136 /* pfn_lo will point to size aligned address if size_aligned is set */
137 new->pfn_lo = limit_pfn - (size + pad_size) + 1;
138 new->pfn_hi = new->pfn_lo + size - 1;
139
140 /* Insert the new_iova into domain rbtree by holding writer lock */
141 /* Add new node and rebalance tree. */
142 {
143 struct rb_node **entry, *parent = NULL;
144
145 /* If we have 'prev', it's a valid place to start the
146 insertion. Otherwise, start from the root. */
147 if (prev)
148 entry = &prev;
149 else
150 entry = &iovad->rbroot.rb_node;
151
152 /* Figure out where to put new node */
153 while (*entry) {
154 struct iova *this = container_of(*entry,
155 struct iova, node);
156 parent = *entry;
157
158 if (new->pfn_lo < this->pfn_lo)
159 entry = &((*entry)->rb_left);
160 else if (new->pfn_lo > this->pfn_lo)
161 entry = &((*entry)->rb_right);
162 else
163 BUG(); /* this should not happen */
164 }
165
166 /* Add new node and rebalance tree. */
167 rb_link_node(&new->node, parent, entry);
168 rb_insert_color(&new->node, &iovad->rbroot);
169 }
170 __cached_rbnode_insert_update(iovad, saved_pfn, new);
171
172 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
173
174
175 return 0;
176}
177
178static void
179iova_insert_rbtree(struct rb_root *root, struct iova *iova)
180{
181 struct rb_node **new = &(root->rb_node), *parent = NULL;
182 /* Figure out where to put new node */
183 while (*new) {
184 struct iova *this = container_of(*new, struct iova, node);
185 parent = *new;
186
187 if (iova->pfn_lo < this->pfn_lo)
188 new = &((*new)->rb_left);
189 else if (iova->pfn_lo > this->pfn_lo)
190 new = &((*new)->rb_right);
191 else
192 BUG(); /* this should not happen */
193 }
194 /* Add new node and rebalance tree. */
195 rb_link_node(&iova->node, parent, new);
196 rb_insert_color(&iova->node, root);
197}
198
199/**
200 * alloc_iova - allocates an iova
201 * @iovad - iova domain in question
202 * @size - size of page frames to allocate
203 * @limit_pfn - max limit address
204 * @size_aligned - set if size_aligned address range is required
205 * This function allocates an iova in the range limit_pfn to IOVA_START_PFN
206 * looking from limit_pfn instead from IOVA_START_PFN. If the size_aligned
207 * flag is set then the allocated address iova->pfn_lo will be naturally
208 * aligned on roundup_power_of_two(size).
209 */
210struct iova *
211alloc_iova(struct iova_domain *iovad, unsigned long size,
212 unsigned long limit_pfn,
213 bool size_aligned)
214{
215 struct iova *new_iova;
216 int ret;
217
218 new_iova = alloc_iova_mem();
219 if (!new_iova)
220 return NULL;
221
222 /* If size aligned is set then round the size to
223 * to next power of two.
224 */
225 if (size_aligned)
226 size = __roundup_pow_of_two(size);
227
228 ret = __alloc_and_insert_iova_range(iovad, size, limit_pfn,
229 new_iova, size_aligned);
230
231 if (ret) {
232 free_iova_mem(new_iova);
233 return NULL;
234 }
235
236 return new_iova;
237}
238
239/**
240 * find_iova - find's an iova for a given pfn
241 * @iovad - iova domain in question.
242 * pfn - page frame number
243 * This function finds and returns an iova belonging to the
244 * given doamin which matches the given pfn.
245 */
246struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn)
247{
248 unsigned long flags;
249 struct rb_node *node;
250
251 /* Take the lock so that no other thread is manipulating the rbtree */
252 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
253 node = iovad->rbroot.rb_node;
254 while (node) {
255 struct iova *iova = container_of(node, struct iova, node);
256
257 /* If pfn falls within iova's range, return iova */
258 if ((pfn >= iova->pfn_lo) && (pfn <= iova->pfn_hi)) {
259 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
260 /* We are not holding the lock while this iova
261 * is referenced by the caller as the same thread
262 * which called this function also calls __free_iova()
263 * and it is by desing that only one thread can possibly
264 * reference a particular iova and hence no conflict.
265 */
266 return iova;
267 }
268
269 if (pfn < iova->pfn_lo)
270 node = node->rb_left;
271 else if (pfn > iova->pfn_lo)
272 node = node->rb_right;
273 }
274
275 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
276 return NULL;
277}
278
279/**
280 * __free_iova - frees the given iova
281 * @iovad: iova domain in question.
282 * @iova: iova in question.
283 * Frees the given iova belonging to the giving domain
284 */
285void
286__free_iova(struct iova_domain *iovad, struct iova *iova)
287{
288 unsigned long flags;
289
290 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
291 __cached_rbnode_delete_update(iovad, iova);
292 rb_erase(&iova->node, &iovad->rbroot);
293 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
294 free_iova_mem(iova);
295}
296
297/**
298 * free_iova - finds and frees the iova for a given pfn
299 * @iovad: - iova domain in question.
300 * @pfn: - pfn that is allocated previously
301 * This functions finds an iova for a given pfn and then
302 * frees the iova from that domain.
303 */
304void
305free_iova(struct iova_domain *iovad, unsigned long pfn)
306{
307 struct iova *iova = find_iova(iovad, pfn);
308 if (iova)
309 __free_iova(iovad, iova);
310
311}
312
313/**
314 * put_iova_domain - destroys the iova doamin
315 * @iovad: - iova domain in question.
316 * All the iova's in that domain are destroyed.
317 */
318void put_iova_domain(struct iova_domain *iovad)
319{
320 struct rb_node *node;
321 unsigned long flags;
322
323 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
324 node = rb_first(&iovad->rbroot);
325 while (node) {
326 struct iova *iova = container_of(node, struct iova, node);
327 rb_erase(node, &iovad->rbroot);
328 free_iova_mem(iova);
329 node = rb_first(&iovad->rbroot);
330 }
331 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
332}
333
334static int
335__is_range_overlap(struct rb_node *node,
336 unsigned long pfn_lo, unsigned long pfn_hi)
337{
338 struct iova *iova = container_of(node, struct iova, node);
339
340 if ((pfn_lo <= iova->pfn_hi) && (pfn_hi >= iova->pfn_lo))
341 return 1;
342 return 0;
343}
344
345static struct iova *
346__insert_new_range(struct iova_domain *iovad,
347 unsigned long pfn_lo, unsigned long pfn_hi)
348{
349 struct iova *iova;
350
351 iova = alloc_iova_mem();
352 if (!iova)
353 return iova;
354
355 iova->pfn_hi = pfn_hi;
356 iova->pfn_lo = pfn_lo;
357 iova_insert_rbtree(&iovad->rbroot, iova);
358 return iova;
359}
360
361static void
362__adjust_overlap_range(struct iova *iova,
363 unsigned long *pfn_lo, unsigned long *pfn_hi)
364{
365 if (*pfn_lo < iova->pfn_lo)
366 iova->pfn_lo = *pfn_lo;
367 if (*pfn_hi > iova->pfn_hi)
368 *pfn_lo = iova->pfn_hi + 1;
369}
370
371/**
372 * reserve_iova - reserves an iova in the given range
373 * @iovad: - iova domain pointer
374 * @pfn_lo: - lower page frame address
375 * @pfn_hi:- higher pfn adderss
376 * This function allocates reserves the address range from pfn_lo to pfn_hi so
377 * that this address is not dished out as part of alloc_iova.
378 */
379struct iova *
380reserve_iova(struct iova_domain *iovad,
381 unsigned long pfn_lo, unsigned long pfn_hi)
382{
383 struct rb_node *node;
384 unsigned long flags;
385 struct iova *iova;
386 unsigned int overlap = 0;
387
388 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
389 for (node = rb_first(&iovad->rbroot); node; node = rb_next(node)) {
390 if (__is_range_overlap(node, pfn_lo, pfn_hi)) {
391 iova = container_of(node, struct iova, node);
392 __adjust_overlap_range(iova, &pfn_lo, &pfn_hi);
393 if ((pfn_lo >= iova->pfn_lo) &&
394 (pfn_hi <= iova->pfn_hi))
395 goto finish;
396 overlap = 1;
397
398 } else if (overlap)
399 break;
400 }
401
402 /* We are here either because this is the first reserver node
403 * or need to insert remaining non overlap addr range
404 */
405 iova = __insert_new_range(iovad, pfn_lo, pfn_hi);
406finish:
407
408 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
409 return iova;
410}
411
412/**
413 * copy_reserved_iova - copies the reserved between domains
414 * @from: - source doamin from where to copy
415 * @to: - destination domin where to copy
416 * This function copies reserved iova's from one doamin to
417 * other.
418 */
419void
420copy_reserved_iova(struct iova_domain *from, struct iova_domain *to)
421{
422 unsigned long flags;
423 struct rb_node *node;
424
425 spin_lock_irqsave(&from->iova_rbtree_lock, flags);
426 for (node = rb_first(&from->rbroot); node; node = rb_next(node)) {
427 struct iova *iova = container_of(node, struct iova, node);
428 struct iova *new_iova;
429 new_iova = reserve_iova(to, iova->pfn_lo, iova->pfn_hi);
430 if (!new_iova)
431 printk(KERN_ERR "Reserve iova range %lx@%lx failed\n",
432 iova->pfn_lo, iova->pfn_lo);
433 }
434 spin_unlock_irqrestore(&from->iova_rbtree_lock, flags);
435}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright © 2006-2009, Intel Corporation.
4 *
5 * Author: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
6 */
7
8#include <linux/iova.h>
9#include <linux/module.h>
10#include <linux/slab.h>
11#include <linux/smp.h>
12#include <linux/bitops.h>
13#include <linux/cpu.h>
14#include <linux/workqueue.h>
15
16/* The anchor node sits above the top of the usable address space */
17#define IOVA_ANCHOR ~0UL
18
19#define IOVA_RANGE_CACHE_MAX_SIZE 6 /* log of max cached IOVA range size (in pages) */
20
21static bool iova_rcache_insert(struct iova_domain *iovad,
22 unsigned long pfn,
23 unsigned long size);
24static unsigned long iova_rcache_get(struct iova_domain *iovad,
25 unsigned long size,
26 unsigned long limit_pfn);
27static void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad);
28static void free_iova_rcaches(struct iova_domain *iovad);
29
30unsigned long iova_rcache_range(void)
31{
32 return PAGE_SIZE << (IOVA_RANGE_CACHE_MAX_SIZE - 1);
33}
34
35static int iova_cpuhp_dead(unsigned int cpu, struct hlist_node *node)
36{
37 struct iova_domain *iovad;
38
39 iovad = hlist_entry_safe(node, struct iova_domain, cpuhp_dead);
40
41 free_cpu_cached_iovas(cpu, iovad);
42 return 0;
43}
44
45static void free_global_cached_iovas(struct iova_domain *iovad);
46
47static struct iova *to_iova(struct rb_node *node)
48{
49 return rb_entry(node, struct iova, node);
50}
51
52void
53init_iova_domain(struct iova_domain *iovad, unsigned long granule,
54 unsigned long start_pfn)
55{
56 /*
57 * IOVA granularity will normally be equal to the smallest
58 * supported IOMMU page size; both *must* be capable of
59 * representing individual CPU pages exactly.
60 */
61 BUG_ON((granule > PAGE_SIZE) || !is_power_of_2(granule));
62
63 spin_lock_init(&iovad->iova_rbtree_lock);
64 iovad->rbroot = RB_ROOT;
65 iovad->cached_node = &iovad->anchor.node;
66 iovad->cached32_node = &iovad->anchor.node;
67 iovad->granule = granule;
68 iovad->start_pfn = start_pfn;
69 iovad->dma_32bit_pfn = 1UL << (32 - iova_shift(iovad));
70 iovad->max32_alloc_size = iovad->dma_32bit_pfn;
71 iovad->anchor.pfn_lo = iovad->anchor.pfn_hi = IOVA_ANCHOR;
72 rb_link_node(&iovad->anchor.node, NULL, &iovad->rbroot.rb_node);
73 rb_insert_color(&iovad->anchor.node, &iovad->rbroot);
74}
75EXPORT_SYMBOL_GPL(init_iova_domain);
76
77static struct rb_node *
78__get_cached_rbnode(struct iova_domain *iovad, unsigned long limit_pfn)
79{
80 if (limit_pfn <= iovad->dma_32bit_pfn)
81 return iovad->cached32_node;
82
83 return iovad->cached_node;
84}
85
86static void
87__cached_rbnode_insert_update(struct iova_domain *iovad, struct iova *new)
88{
89 if (new->pfn_hi < iovad->dma_32bit_pfn)
90 iovad->cached32_node = &new->node;
91 else
92 iovad->cached_node = &new->node;
93}
94
95static void
96__cached_rbnode_delete_update(struct iova_domain *iovad, struct iova *free)
97{
98 struct iova *cached_iova;
99
100 cached_iova = to_iova(iovad->cached32_node);
101 if (free == cached_iova ||
102 (free->pfn_hi < iovad->dma_32bit_pfn &&
103 free->pfn_lo >= cached_iova->pfn_lo))
104 iovad->cached32_node = rb_next(&free->node);
105
106 if (free->pfn_lo < iovad->dma_32bit_pfn)
107 iovad->max32_alloc_size = iovad->dma_32bit_pfn;
108
109 cached_iova = to_iova(iovad->cached_node);
110 if (free->pfn_lo >= cached_iova->pfn_lo)
111 iovad->cached_node = rb_next(&free->node);
112}
113
114static struct rb_node *iova_find_limit(struct iova_domain *iovad, unsigned long limit_pfn)
115{
116 struct rb_node *node, *next;
117 /*
118 * Ideally what we'd like to judge here is whether limit_pfn is close
119 * enough to the highest-allocated IOVA that starting the allocation
120 * walk from the anchor node will be quicker than this initial work to
121 * find an exact starting point (especially if that ends up being the
122 * anchor node anyway). This is an incredibly crude approximation which
123 * only really helps the most likely case, but is at least trivially easy.
124 */
125 if (limit_pfn > iovad->dma_32bit_pfn)
126 return &iovad->anchor.node;
127
128 node = iovad->rbroot.rb_node;
129 while (to_iova(node)->pfn_hi < limit_pfn)
130 node = node->rb_right;
131
132search_left:
133 while (node->rb_left && to_iova(node->rb_left)->pfn_lo >= limit_pfn)
134 node = node->rb_left;
135
136 if (!node->rb_left)
137 return node;
138
139 next = node->rb_left;
140 while (next->rb_right) {
141 next = next->rb_right;
142 if (to_iova(next)->pfn_lo >= limit_pfn) {
143 node = next;
144 goto search_left;
145 }
146 }
147
148 return node;
149}
150
151/* Insert the iova into domain rbtree by holding writer lock */
152static void
153iova_insert_rbtree(struct rb_root *root, struct iova *iova,
154 struct rb_node *start)
155{
156 struct rb_node **new, *parent = NULL;
157
158 new = (start) ? &start : &(root->rb_node);
159 /* Figure out where to put new node */
160 while (*new) {
161 struct iova *this = to_iova(*new);
162
163 parent = *new;
164
165 if (iova->pfn_lo < this->pfn_lo)
166 new = &((*new)->rb_left);
167 else if (iova->pfn_lo > this->pfn_lo)
168 new = &((*new)->rb_right);
169 else {
170 WARN_ON(1); /* this should not happen */
171 return;
172 }
173 }
174 /* Add new node and rebalance tree. */
175 rb_link_node(&iova->node, parent, new);
176 rb_insert_color(&iova->node, root);
177}
178
179static int __alloc_and_insert_iova_range(struct iova_domain *iovad,
180 unsigned long size, unsigned long limit_pfn,
181 struct iova *new, bool size_aligned)
182{
183 struct rb_node *curr, *prev;
184 struct iova *curr_iova;
185 unsigned long flags;
186 unsigned long new_pfn, retry_pfn;
187 unsigned long align_mask = ~0UL;
188 unsigned long high_pfn = limit_pfn, low_pfn = iovad->start_pfn;
189
190 if (size_aligned)
191 align_mask <<= fls_long(size - 1);
192
193 /* Walk the tree backwards */
194 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
195 if (limit_pfn <= iovad->dma_32bit_pfn &&
196 size >= iovad->max32_alloc_size)
197 goto iova32_full;
198
199 curr = __get_cached_rbnode(iovad, limit_pfn);
200 curr_iova = to_iova(curr);
201 retry_pfn = curr_iova->pfn_hi;
202
203retry:
204 do {
205 high_pfn = min(high_pfn, curr_iova->pfn_lo);
206 new_pfn = (high_pfn - size) & align_mask;
207 prev = curr;
208 curr = rb_prev(curr);
209 curr_iova = to_iova(curr);
210 } while (curr && new_pfn <= curr_iova->pfn_hi && new_pfn >= low_pfn);
211
212 if (high_pfn < size || new_pfn < low_pfn) {
213 if (low_pfn == iovad->start_pfn && retry_pfn < limit_pfn) {
214 high_pfn = limit_pfn;
215 low_pfn = retry_pfn + 1;
216 curr = iova_find_limit(iovad, limit_pfn);
217 curr_iova = to_iova(curr);
218 goto retry;
219 }
220 iovad->max32_alloc_size = size;
221 goto iova32_full;
222 }
223
224 /* pfn_lo will point to size aligned address if size_aligned is set */
225 new->pfn_lo = new_pfn;
226 new->pfn_hi = new->pfn_lo + size - 1;
227
228 /* If we have 'prev', it's a valid place to start the insertion. */
229 iova_insert_rbtree(&iovad->rbroot, new, prev);
230 __cached_rbnode_insert_update(iovad, new);
231
232 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
233 return 0;
234
235iova32_full:
236 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
237 return -ENOMEM;
238}
239
240static struct kmem_cache *iova_cache;
241static unsigned int iova_cache_users;
242static DEFINE_MUTEX(iova_cache_mutex);
243
244static struct iova *alloc_iova_mem(void)
245{
246 return kmem_cache_zalloc(iova_cache, GFP_ATOMIC | __GFP_NOWARN);
247}
248
249static void free_iova_mem(struct iova *iova)
250{
251 if (iova->pfn_lo != IOVA_ANCHOR)
252 kmem_cache_free(iova_cache, iova);
253}
254
255int iova_cache_get(void)
256{
257 mutex_lock(&iova_cache_mutex);
258 if (!iova_cache_users) {
259 int ret;
260
261 ret = cpuhp_setup_state_multi(CPUHP_IOMMU_IOVA_DEAD, "iommu/iova:dead", NULL,
262 iova_cpuhp_dead);
263 if (ret) {
264 mutex_unlock(&iova_cache_mutex);
265 pr_err("Couldn't register cpuhp handler\n");
266 return ret;
267 }
268
269 iova_cache = kmem_cache_create(
270 "iommu_iova", sizeof(struct iova), 0,
271 SLAB_HWCACHE_ALIGN, NULL);
272 if (!iova_cache) {
273 cpuhp_remove_multi_state(CPUHP_IOMMU_IOVA_DEAD);
274 mutex_unlock(&iova_cache_mutex);
275 pr_err("Couldn't create iova cache\n");
276 return -ENOMEM;
277 }
278 }
279
280 iova_cache_users++;
281 mutex_unlock(&iova_cache_mutex);
282
283 return 0;
284}
285EXPORT_SYMBOL_GPL(iova_cache_get);
286
287void iova_cache_put(void)
288{
289 mutex_lock(&iova_cache_mutex);
290 if (WARN_ON(!iova_cache_users)) {
291 mutex_unlock(&iova_cache_mutex);
292 return;
293 }
294 iova_cache_users--;
295 if (!iova_cache_users) {
296 cpuhp_remove_multi_state(CPUHP_IOMMU_IOVA_DEAD);
297 kmem_cache_destroy(iova_cache);
298 }
299 mutex_unlock(&iova_cache_mutex);
300}
301EXPORT_SYMBOL_GPL(iova_cache_put);
302
303/**
304 * alloc_iova - allocates an iova
305 * @iovad: - iova domain in question
306 * @size: - size of page frames to allocate
307 * @limit_pfn: - max limit address
308 * @size_aligned: - set if size_aligned address range is required
309 * This function allocates an iova in the range iovad->start_pfn to limit_pfn,
310 * searching top-down from limit_pfn to iovad->start_pfn. If the size_aligned
311 * flag is set then the allocated address iova->pfn_lo will be naturally
312 * aligned on roundup_power_of_two(size).
313 */
314struct iova *
315alloc_iova(struct iova_domain *iovad, unsigned long size,
316 unsigned long limit_pfn,
317 bool size_aligned)
318{
319 struct iova *new_iova;
320 int ret;
321
322 new_iova = alloc_iova_mem();
323 if (!new_iova)
324 return NULL;
325
326 ret = __alloc_and_insert_iova_range(iovad, size, limit_pfn + 1,
327 new_iova, size_aligned);
328
329 if (ret) {
330 free_iova_mem(new_iova);
331 return NULL;
332 }
333
334 return new_iova;
335}
336EXPORT_SYMBOL_GPL(alloc_iova);
337
338static struct iova *
339private_find_iova(struct iova_domain *iovad, unsigned long pfn)
340{
341 struct rb_node *node = iovad->rbroot.rb_node;
342
343 assert_spin_locked(&iovad->iova_rbtree_lock);
344
345 while (node) {
346 struct iova *iova = to_iova(node);
347
348 if (pfn < iova->pfn_lo)
349 node = node->rb_left;
350 else if (pfn > iova->pfn_hi)
351 node = node->rb_right;
352 else
353 return iova; /* pfn falls within iova's range */
354 }
355
356 return NULL;
357}
358
359static void remove_iova(struct iova_domain *iovad, struct iova *iova)
360{
361 assert_spin_locked(&iovad->iova_rbtree_lock);
362 __cached_rbnode_delete_update(iovad, iova);
363 rb_erase(&iova->node, &iovad->rbroot);
364}
365
366/**
367 * find_iova - finds an iova for a given pfn
368 * @iovad: - iova domain in question.
369 * @pfn: - page frame number
370 * This function finds and returns an iova belonging to the
371 * given domain which matches the given pfn.
372 */
373struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn)
374{
375 unsigned long flags;
376 struct iova *iova;
377
378 /* Take the lock so that no other thread is manipulating the rbtree */
379 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
380 iova = private_find_iova(iovad, pfn);
381 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
382 return iova;
383}
384EXPORT_SYMBOL_GPL(find_iova);
385
386/**
387 * __free_iova - frees the given iova
388 * @iovad: iova domain in question.
389 * @iova: iova in question.
390 * Frees the given iova belonging to the giving domain
391 */
392void
393__free_iova(struct iova_domain *iovad, struct iova *iova)
394{
395 unsigned long flags;
396
397 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
398 remove_iova(iovad, iova);
399 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
400 free_iova_mem(iova);
401}
402EXPORT_SYMBOL_GPL(__free_iova);
403
404/**
405 * free_iova - finds and frees the iova for a given pfn
406 * @iovad: - iova domain in question.
407 * @pfn: - pfn that is allocated previously
408 * This functions finds an iova for a given pfn and then
409 * frees the iova from that domain.
410 */
411void
412free_iova(struct iova_domain *iovad, unsigned long pfn)
413{
414 unsigned long flags;
415 struct iova *iova;
416
417 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
418 iova = private_find_iova(iovad, pfn);
419 if (!iova) {
420 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
421 return;
422 }
423 remove_iova(iovad, iova);
424 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
425 free_iova_mem(iova);
426}
427EXPORT_SYMBOL_GPL(free_iova);
428
429/**
430 * alloc_iova_fast - allocates an iova from rcache
431 * @iovad: - iova domain in question
432 * @size: - size of page frames to allocate
433 * @limit_pfn: - max limit address
434 * @flush_rcache: - set to flush rcache on regular allocation failure
435 * This function tries to satisfy an iova allocation from the rcache,
436 * and falls back to regular allocation on failure. If regular allocation
437 * fails too and the flush_rcache flag is set then the rcache will be flushed.
438*/
439unsigned long
440alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
441 unsigned long limit_pfn, bool flush_rcache)
442{
443 unsigned long iova_pfn;
444 struct iova *new_iova;
445
446 /*
447 * Freeing non-power-of-two-sized allocations back into the IOVA caches
448 * will come back to bite us badly, so we have to waste a bit of space
449 * rounding up anything cacheable to make sure that can't happen. The
450 * order of the unadjusted size will still match upon freeing.
451 */
452 if (size < (1 << (IOVA_RANGE_CACHE_MAX_SIZE - 1)))
453 size = roundup_pow_of_two(size);
454
455 iova_pfn = iova_rcache_get(iovad, size, limit_pfn + 1);
456 if (iova_pfn)
457 return iova_pfn;
458
459retry:
460 new_iova = alloc_iova(iovad, size, limit_pfn, true);
461 if (!new_iova) {
462 unsigned int cpu;
463
464 if (!flush_rcache)
465 return 0;
466
467 /* Try replenishing IOVAs by flushing rcache. */
468 flush_rcache = false;
469 for_each_online_cpu(cpu)
470 free_cpu_cached_iovas(cpu, iovad);
471 free_global_cached_iovas(iovad);
472 goto retry;
473 }
474
475 return new_iova->pfn_lo;
476}
477EXPORT_SYMBOL_GPL(alloc_iova_fast);
478
479/**
480 * free_iova_fast - free iova pfn range into rcache
481 * @iovad: - iova domain in question.
482 * @pfn: - pfn that is allocated previously
483 * @size: - # of pages in range
484 * This functions frees an iova range by trying to put it into the rcache,
485 * falling back to regular iova deallocation via free_iova() if this fails.
486 */
487void
488free_iova_fast(struct iova_domain *iovad, unsigned long pfn, unsigned long size)
489{
490 if (iova_rcache_insert(iovad, pfn, size))
491 return;
492
493 free_iova(iovad, pfn);
494}
495EXPORT_SYMBOL_GPL(free_iova_fast);
496
497static void iova_domain_free_rcaches(struct iova_domain *iovad)
498{
499 cpuhp_state_remove_instance_nocalls(CPUHP_IOMMU_IOVA_DEAD,
500 &iovad->cpuhp_dead);
501 free_iova_rcaches(iovad);
502}
503
504/**
505 * put_iova_domain - destroys the iova domain
506 * @iovad: - iova domain in question.
507 * All the iova's in that domain are destroyed.
508 */
509void put_iova_domain(struct iova_domain *iovad)
510{
511 struct iova *iova, *tmp;
512
513 if (iovad->rcaches)
514 iova_domain_free_rcaches(iovad);
515
516 rbtree_postorder_for_each_entry_safe(iova, tmp, &iovad->rbroot, node)
517 free_iova_mem(iova);
518}
519EXPORT_SYMBOL_GPL(put_iova_domain);
520
521static int
522__is_range_overlap(struct rb_node *node,
523 unsigned long pfn_lo, unsigned long pfn_hi)
524{
525 struct iova *iova = to_iova(node);
526
527 if ((pfn_lo <= iova->pfn_hi) && (pfn_hi >= iova->pfn_lo))
528 return 1;
529 return 0;
530}
531
532static inline struct iova *
533alloc_and_init_iova(unsigned long pfn_lo, unsigned long pfn_hi)
534{
535 struct iova *iova;
536
537 iova = alloc_iova_mem();
538 if (iova) {
539 iova->pfn_lo = pfn_lo;
540 iova->pfn_hi = pfn_hi;
541 }
542
543 return iova;
544}
545
546static struct iova *
547__insert_new_range(struct iova_domain *iovad,
548 unsigned long pfn_lo, unsigned long pfn_hi)
549{
550 struct iova *iova;
551
552 iova = alloc_and_init_iova(pfn_lo, pfn_hi);
553 if (iova)
554 iova_insert_rbtree(&iovad->rbroot, iova, NULL);
555
556 return iova;
557}
558
559static void
560__adjust_overlap_range(struct iova *iova,
561 unsigned long *pfn_lo, unsigned long *pfn_hi)
562{
563 if (*pfn_lo < iova->pfn_lo)
564 iova->pfn_lo = *pfn_lo;
565 if (*pfn_hi > iova->pfn_hi)
566 *pfn_lo = iova->pfn_hi + 1;
567}
568
569/**
570 * reserve_iova - reserves an iova in the given range
571 * @iovad: - iova domain pointer
572 * @pfn_lo: - lower page frame address
573 * @pfn_hi:- higher pfn adderss
574 * This function allocates reserves the address range from pfn_lo to pfn_hi so
575 * that this address is not dished out as part of alloc_iova.
576 */
577struct iova *
578reserve_iova(struct iova_domain *iovad,
579 unsigned long pfn_lo, unsigned long pfn_hi)
580{
581 struct rb_node *node;
582 unsigned long flags;
583 struct iova *iova;
584 unsigned int overlap = 0;
585
586 /* Don't allow nonsensical pfns */
587 if (WARN_ON((pfn_hi | pfn_lo) > (ULLONG_MAX >> iova_shift(iovad))))
588 return NULL;
589
590 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
591 for (node = rb_first(&iovad->rbroot); node; node = rb_next(node)) {
592 if (__is_range_overlap(node, pfn_lo, pfn_hi)) {
593 iova = to_iova(node);
594 __adjust_overlap_range(iova, &pfn_lo, &pfn_hi);
595 if ((pfn_lo >= iova->pfn_lo) &&
596 (pfn_hi <= iova->pfn_hi))
597 goto finish;
598 overlap = 1;
599
600 } else if (overlap)
601 break;
602 }
603
604 /* We are here either because this is the first reserver node
605 * or need to insert remaining non overlap addr range
606 */
607 iova = __insert_new_range(iovad, pfn_lo, pfn_hi);
608finish:
609
610 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
611 return iova;
612}
613EXPORT_SYMBOL_GPL(reserve_iova);
614
615/*
616 * Magazine caches for IOVA ranges. For an introduction to magazines,
617 * see the USENIX 2001 paper "Magazines and Vmem: Extending the Slab
618 * Allocator to Many CPUs and Arbitrary Resources" by Bonwick and Adams.
619 * For simplicity, we use a static magazine size and don't implement the
620 * dynamic size tuning described in the paper.
621 */
622
623/*
624 * As kmalloc's buffer size is fixed to power of 2, 127 is chosen to
625 * assure size of 'iova_magazine' to be 1024 bytes, so that no memory
626 * will be wasted. Since only full magazines are inserted into the depot,
627 * we don't need to waste PFN capacity on a separate list head either.
628 */
629#define IOVA_MAG_SIZE 127
630
631#define IOVA_DEPOT_DELAY msecs_to_jiffies(100)
632
633struct iova_magazine {
634 union {
635 unsigned long size;
636 struct iova_magazine *next;
637 };
638 unsigned long pfns[IOVA_MAG_SIZE];
639};
640static_assert(!(sizeof(struct iova_magazine) & (sizeof(struct iova_magazine) - 1)));
641
642struct iova_cpu_rcache {
643 spinlock_t lock;
644 struct iova_magazine *loaded;
645 struct iova_magazine *prev;
646};
647
648struct iova_rcache {
649 spinlock_t lock;
650 unsigned int depot_size;
651 struct iova_magazine *depot;
652 struct iova_cpu_rcache __percpu *cpu_rcaches;
653 struct iova_domain *iovad;
654 struct delayed_work work;
655};
656
657static struct iova_magazine *iova_magazine_alloc(gfp_t flags)
658{
659 struct iova_magazine *mag;
660
661 mag = kmalloc(sizeof(*mag), flags);
662 if (mag)
663 mag->size = 0;
664
665 return mag;
666}
667
668static void iova_magazine_free(struct iova_magazine *mag)
669{
670 kfree(mag);
671}
672
673static void
674iova_magazine_free_pfns(struct iova_magazine *mag, struct iova_domain *iovad)
675{
676 unsigned long flags;
677 int i;
678
679 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
680
681 for (i = 0 ; i < mag->size; ++i) {
682 struct iova *iova = private_find_iova(iovad, mag->pfns[i]);
683
684 if (WARN_ON(!iova))
685 continue;
686
687 remove_iova(iovad, iova);
688 free_iova_mem(iova);
689 }
690
691 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
692
693 mag->size = 0;
694}
695
696static bool iova_magazine_full(struct iova_magazine *mag)
697{
698 return mag->size == IOVA_MAG_SIZE;
699}
700
701static bool iova_magazine_empty(struct iova_magazine *mag)
702{
703 return mag->size == 0;
704}
705
706static unsigned long iova_magazine_pop(struct iova_magazine *mag,
707 unsigned long limit_pfn)
708{
709 int i;
710 unsigned long pfn;
711
712 /* Only fall back to the rbtree if we have no suitable pfns at all */
713 for (i = mag->size - 1; mag->pfns[i] > limit_pfn; i--)
714 if (i == 0)
715 return 0;
716
717 /* Swap it to pop it */
718 pfn = mag->pfns[i];
719 mag->pfns[i] = mag->pfns[--mag->size];
720
721 return pfn;
722}
723
724static void iova_magazine_push(struct iova_magazine *mag, unsigned long pfn)
725{
726 mag->pfns[mag->size++] = pfn;
727}
728
729static struct iova_magazine *iova_depot_pop(struct iova_rcache *rcache)
730{
731 struct iova_magazine *mag = rcache->depot;
732
733 rcache->depot = mag->next;
734 mag->size = IOVA_MAG_SIZE;
735 rcache->depot_size--;
736 return mag;
737}
738
739static void iova_depot_push(struct iova_rcache *rcache, struct iova_magazine *mag)
740{
741 mag->next = rcache->depot;
742 rcache->depot = mag;
743 rcache->depot_size++;
744}
745
746static void iova_depot_work_func(struct work_struct *work)
747{
748 struct iova_rcache *rcache = container_of(work, typeof(*rcache), work.work);
749 struct iova_magazine *mag = NULL;
750 unsigned long flags;
751
752 spin_lock_irqsave(&rcache->lock, flags);
753 if (rcache->depot_size > num_online_cpus())
754 mag = iova_depot_pop(rcache);
755 spin_unlock_irqrestore(&rcache->lock, flags);
756
757 if (mag) {
758 iova_magazine_free_pfns(mag, rcache->iovad);
759 iova_magazine_free(mag);
760 schedule_delayed_work(&rcache->work, IOVA_DEPOT_DELAY);
761 }
762}
763
764int iova_domain_init_rcaches(struct iova_domain *iovad)
765{
766 unsigned int cpu;
767 int i, ret;
768
769 iovad->rcaches = kcalloc(IOVA_RANGE_CACHE_MAX_SIZE,
770 sizeof(struct iova_rcache),
771 GFP_KERNEL);
772 if (!iovad->rcaches)
773 return -ENOMEM;
774
775 for (i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) {
776 struct iova_cpu_rcache *cpu_rcache;
777 struct iova_rcache *rcache;
778
779 rcache = &iovad->rcaches[i];
780 spin_lock_init(&rcache->lock);
781 rcache->iovad = iovad;
782 INIT_DELAYED_WORK(&rcache->work, iova_depot_work_func);
783 rcache->cpu_rcaches = __alloc_percpu(sizeof(*cpu_rcache),
784 cache_line_size());
785 if (!rcache->cpu_rcaches) {
786 ret = -ENOMEM;
787 goto out_err;
788 }
789 for_each_possible_cpu(cpu) {
790 cpu_rcache = per_cpu_ptr(rcache->cpu_rcaches, cpu);
791
792 spin_lock_init(&cpu_rcache->lock);
793 cpu_rcache->loaded = iova_magazine_alloc(GFP_KERNEL);
794 cpu_rcache->prev = iova_magazine_alloc(GFP_KERNEL);
795 if (!cpu_rcache->loaded || !cpu_rcache->prev) {
796 ret = -ENOMEM;
797 goto out_err;
798 }
799 }
800 }
801
802 ret = cpuhp_state_add_instance_nocalls(CPUHP_IOMMU_IOVA_DEAD,
803 &iovad->cpuhp_dead);
804 if (ret)
805 goto out_err;
806 return 0;
807
808out_err:
809 free_iova_rcaches(iovad);
810 return ret;
811}
812EXPORT_SYMBOL_GPL(iova_domain_init_rcaches);
813
814/*
815 * Try inserting IOVA range starting with 'iova_pfn' into 'rcache', and
816 * return true on success. Can fail if rcache is full and we can't free
817 * space, and free_iova() (our only caller) will then return the IOVA
818 * range to the rbtree instead.
819 */
820static bool __iova_rcache_insert(struct iova_domain *iovad,
821 struct iova_rcache *rcache,
822 unsigned long iova_pfn)
823{
824 struct iova_cpu_rcache *cpu_rcache;
825 bool can_insert = false;
826 unsigned long flags;
827
828 cpu_rcache = raw_cpu_ptr(rcache->cpu_rcaches);
829 spin_lock_irqsave(&cpu_rcache->lock, flags);
830
831 if (!iova_magazine_full(cpu_rcache->loaded)) {
832 can_insert = true;
833 } else if (!iova_magazine_full(cpu_rcache->prev)) {
834 swap(cpu_rcache->prev, cpu_rcache->loaded);
835 can_insert = true;
836 } else {
837 struct iova_magazine *new_mag = iova_magazine_alloc(GFP_ATOMIC);
838
839 if (new_mag) {
840 spin_lock(&rcache->lock);
841 iova_depot_push(rcache, cpu_rcache->loaded);
842 spin_unlock(&rcache->lock);
843 schedule_delayed_work(&rcache->work, IOVA_DEPOT_DELAY);
844
845 cpu_rcache->loaded = new_mag;
846 can_insert = true;
847 }
848 }
849
850 if (can_insert)
851 iova_magazine_push(cpu_rcache->loaded, iova_pfn);
852
853 spin_unlock_irqrestore(&cpu_rcache->lock, flags);
854
855 return can_insert;
856}
857
858static bool iova_rcache_insert(struct iova_domain *iovad, unsigned long pfn,
859 unsigned long size)
860{
861 unsigned int log_size = order_base_2(size);
862
863 if (log_size >= IOVA_RANGE_CACHE_MAX_SIZE)
864 return false;
865
866 return __iova_rcache_insert(iovad, &iovad->rcaches[log_size], pfn);
867}
868
869/*
870 * Caller wants to allocate a new IOVA range from 'rcache'. If we can
871 * satisfy the request, return a matching non-NULL range and remove
872 * it from the 'rcache'.
873 */
874static unsigned long __iova_rcache_get(struct iova_rcache *rcache,
875 unsigned long limit_pfn)
876{
877 struct iova_cpu_rcache *cpu_rcache;
878 unsigned long iova_pfn = 0;
879 bool has_pfn = false;
880 unsigned long flags;
881
882 cpu_rcache = raw_cpu_ptr(rcache->cpu_rcaches);
883 spin_lock_irqsave(&cpu_rcache->lock, flags);
884
885 if (!iova_magazine_empty(cpu_rcache->loaded)) {
886 has_pfn = true;
887 } else if (!iova_magazine_empty(cpu_rcache->prev)) {
888 swap(cpu_rcache->prev, cpu_rcache->loaded);
889 has_pfn = true;
890 } else {
891 spin_lock(&rcache->lock);
892 if (rcache->depot) {
893 iova_magazine_free(cpu_rcache->loaded);
894 cpu_rcache->loaded = iova_depot_pop(rcache);
895 has_pfn = true;
896 }
897 spin_unlock(&rcache->lock);
898 }
899
900 if (has_pfn)
901 iova_pfn = iova_magazine_pop(cpu_rcache->loaded, limit_pfn);
902
903 spin_unlock_irqrestore(&cpu_rcache->lock, flags);
904
905 return iova_pfn;
906}
907
908/*
909 * Try to satisfy IOVA allocation range from rcache. Fail if requested
910 * size is too big or the DMA limit we are given isn't satisfied by the
911 * top element in the magazine.
912 */
913static unsigned long iova_rcache_get(struct iova_domain *iovad,
914 unsigned long size,
915 unsigned long limit_pfn)
916{
917 unsigned int log_size = order_base_2(size);
918
919 if (log_size >= IOVA_RANGE_CACHE_MAX_SIZE)
920 return 0;
921
922 return __iova_rcache_get(&iovad->rcaches[log_size], limit_pfn - size);
923}
924
925/*
926 * free rcache data structures.
927 */
928static void free_iova_rcaches(struct iova_domain *iovad)
929{
930 struct iova_rcache *rcache;
931 struct iova_cpu_rcache *cpu_rcache;
932 unsigned int cpu;
933
934 for (int i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) {
935 rcache = &iovad->rcaches[i];
936 if (!rcache->cpu_rcaches)
937 break;
938 for_each_possible_cpu(cpu) {
939 cpu_rcache = per_cpu_ptr(rcache->cpu_rcaches, cpu);
940 iova_magazine_free(cpu_rcache->loaded);
941 iova_magazine_free(cpu_rcache->prev);
942 }
943 free_percpu(rcache->cpu_rcaches);
944 cancel_delayed_work_sync(&rcache->work);
945 while (rcache->depot)
946 iova_magazine_free(iova_depot_pop(rcache));
947 }
948
949 kfree(iovad->rcaches);
950 iovad->rcaches = NULL;
951}
952
953/*
954 * free all the IOVA ranges cached by a cpu (used when cpu is unplugged)
955 */
956static void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad)
957{
958 struct iova_cpu_rcache *cpu_rcache;
959 struct iova_rcache *rcache;
960 unsigned long flags;
961 int i;
962
963 for (i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) {
964 rcache = &iovad->rcaches[i];
965 cpu_rcache = per_cpu_ptr(rcache->cpu_rcaches, cpu);
966 spin_lock_irqsave(&cpu_rcache->lock, flags);
967 iova_magazine_free_pfns(cpu_rcache->loaded, iovad);
968 iova_magazine_free_pfns(cpu_rcache->prev, iovad);
969 spin_unlock_irqrestore(&cpu_rcache->lock, flags);
970 }
971}
972
973/*
974 * free all the IOVA ranges of global cache
975 */
976static void free_global_cached_iovas(struct iova_domain *iovad)
977{
978 struct iova_rcache *rcache;
979 unsigned long flags;
980
981 for (int i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) {
982 rcache = &iovad->rcaches[i];
983 spin_lock_irqsave(&rcache->lock, flags);
984 while (rcache->depot) {
985 struct iova_magazine *mag = iova_depot_pop(rcache);
986
987 iova_magazine_free_pfns(mag, iovad);
988 iova_magazine_free(mag);
989 }
990 spin_unlock_irqrestore(&rcache->lock, flags);
991 }
992}
993MODULE_AUTHOR("Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>");
994MODULE_LICENSE("GPL");