blob: 3b3a360b429a8ac78b5089a98c09027aa40634a3 [file] [log] [blame]
David S. Miller74bf4312006-01-31 18:29:18 -08001/* arch/sparc64/mm/tsb.c
2 *
David S. Millera3cf5e62008-08-03 00:01:05 -07003 * Copyright (C) 2006, 2008 David S. Miller <davem@davemloft.net>
David S. Miller74bf4312006-01-31 18:29:18 -08004 */
5
6#include <linux/kernel.h>
David S. Millera3cf5e62008-08-03 00:01:05 -07007#include <linux/preempt.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +09008#include <linux/slab.h>
David S. Miller74bf4312006-01-31 18:29:18 -08009#include <asm/page.h>
David S. Miller98c55842006-01-31 18:31:20 -080010#include <asm/pgtable.h>
David S. Millerf36391d2013-04-19 17:26:26 -040011#include <asm/mmu_context.h>
David S. Millerbd407912006-01-31 18:31:38 -080012#include <asm/tsb.h>
David S. Millerf36391d2013-04-19 17:26:26 -040013#include <asm/tlb.h>
David S. Miller9b4006d2006-03-18 18:12:42 -080014#include <asm/oplib.h>
David S. Miller74bf4312006-01-31 18:29:18 -080015
David S. Miller74bf4312006-01-31 18:29:18 -080016extern struct tsb swapper_tsb[KERNEL_TSB_NENTRIES];
17
David S. Millerdcc1e8d2006-03-22 00:49:59 -080018static inline unsigned long tsb_hash(unsigned long vaddr, unsigned long hash_shift, unsigned long nentries)
David S. Miller74bf4312006-01-31 18:29:18 -080019{
David S. Millerdcc1e8d2006-03-22 00:49:59 -080020 vaddr >>= hash_shift;
David S. Miller98c55842006-01-31 18:31:20 -080021 return vaddr & (nentries - 1);
David S. Miller74bf4312006-01-31 18:29:18 -080022}
23
David S. Miller8b234272006-02-17 18:01:02 -080024static inline int tag_compare(unsigned long tag, unsigned long vaddr)
David S. Miller74bf4312006-01-31 18:29:18 -080025{
David S. Miller8b234272006-02-17 18:01:02 -080026 return (tag == (vaddr >> 22));
David S. Miller74bf4312006-01-31 18:29:18 -080027}
28
29/* TSB flushes need only occur on the processor initiating the address
30 * space modification, not on each cpu the address space has run on.
31 * Only the TLB flush needs that treatment.
32 */
33
34void flush_tsb_kernel_range(unsigned long start, unsigned long end)
35{
36 unsigned long v;
37
38 for (v = start; v < end; v += PAGE_SIZE) {
David S. Millerdcc1e8d2006-03-22 00:49:59 -080039 unsigned long hash = tsb_hash(v, PAGE_SHIFT,
40 KERNEL_TSB_NENTRIES);
David S. Miller98c55842006-01-31 18:31:20 -080041 struct tsb *ent = &swapper_tsb[hash];
David S. Miller74bf4312006-01-31 18:29:18 -080042
David S. Miller293666b2008-11-15 13:33:25 -080043 if (tag_compare(ent->tag, v))
David S. Miller8b234272006-02-17 18:01:02 -080044 ent->tag = (1UL << TSB_TAG_INVALID_BIT);
David S. Miller74bf4312006-01-31 18:29:18 -080045 }
46}
47
David S. Millerf36391d2013-04-19 17:26:26 -040048static void __flush_tsb_one_entry(unsigned long tsb, unsigned long v,
49 unsigned long hash_shift,
50 unsigned long nentries)
51{
52 unsigned long tag, ent, hash;
53
54 v &= ~0x1UL;
55 hash = tsb_hash(v, hash_shift, nentries);
56 ent = tsb + (hash * sizeof(struct tsb));
57 tag = (v >> 22UL);
58
59 tsb_flush(ent, tag);
60}
61
Peter Zijlstra90f08e32011-05-24 17:11:50 -070062static void __flush_tsb_one(struct tlb_batch *tb, unsigned long hash_shift,
63 unsigned long tsb, unsigned long nentries)
David S. Miller74bf4312006-01-31 18:29:18 -080064{
David S. Millerdcc1e8d2006-03-22 00:49:59 -080065 unsigned long i;
David S. Miller74bf4312006-01-31 18:29:18 -080066
David S. Millerf36391d2013-04-19 17:26:26 -040067 for (i = 0; i < tb->tlb_nr; i++)
68 __flush_tsb_one_entry(tsb, tb->vaddrs[i], hash_shift, nentries);
David S. Millerdcc1e8d2006-03-22 00:49:59 -080069}
David S. Miller7a1ac522006-03-16 02:02:32 -080070
Peter Zijlstra90f08e32011-05-24 17:11:50 -070071void flush_tsb_user(struct tlb_batch *tb)
David S. Millerdcc1e8d2006-03-22 00:49:59 -080072{
Peter Zijlstra90f08e32011-05-24 17:11:50 -070073 struct mm_struct *mm = tb->mm;
David S. Millerdcc1e8d2006-03-22 00:49:59 -080074 unsigned long nentries, base, flags;
75
76 spin_lock_irqsave(&mm->context.lock, flags);
77
78 base = (unsigned long) mm->context.tsb_block[MM_TSB_BASE].tsb;
79 nentries = mm->context.tsb_block[MM_TSB_BASE].tsb_nentries;
80 if (tlb_type == cheetah_plus || tlb_type == hypervisor)
81 base = __pa(base);
Peter Zijlstra90f08e32011-05-24 17:11:50 -070082 __flush_tsb_one(tb, PAGE_SHIFT, base, nentries);
David S. Millerdcc1e8d2006-03-22 00:49:59 -080083
David Miller9e695d22012-10-08 16:34:29 -070084#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
David S. Millerdcc1e8d2006-03-22 00:49:59 -080085 if (mm->context.tsb_block[MM_TSB_HUGE].tsb) {
86 base = (unsigned long) mm->context.tsb_block[MM_TSB_HUGE].tsb;
87 nentries = mm->context.tsb_block[MM_TSB_HUGE].tsb_nentries;
88 if (tlb_type == cheetah_plus || tlb_type == hypervisor)
89 base = __pa(base);
David S. Miller37b3a8f2013-09-25 13:48:49 -070090 __flush_tsb_one(tb, REAL_HPAGE_SHIFT, base, nentries);
David S. Millerdcc1e8d2006-03-22 00:49:59 -080091 }
92#endif
David S. Miller7a1ac522006-03-16 02:02:32 -080093 spin_unlock_irqrestore(&mm->context.lock, flags);
David S. Miller74bf4312006-01-31 18:29:18 -080094}
David S. Miller09f94282006-01-31 18:31:06 -080095
David S. Millerf36391d2013-04-19 17:26:26 -040096void flush_tsb_user_page(struct mm_struct *mm, unsigned long vaddr)
97{
98 unsigned long nentries, base, flags;
99
100 spin_lock_irqsave(&mm->context.lock, flags);
101
102 base = (unsigned long) mm->context.tsb_block[MM_TSB_BASE].tsb;
103 nentries = mm->context.tsb_block[MM_TSB_BASE].tsb_nentries;
104 if (tlb_type == cheetah_plus || tlb_type == hypervisor)
105 base = __pa(base);
106 __flush_tsb_one_entry(base, vaddr, PAGE_SHIFT, nentries);
107
108#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
109 if (mm->context.tsb_block[MM_TSB_HUGE].tsb) {
110 base = (unsigned long) mm->context.tsb_block[MM_TSB_HUGE].tsb;
111 nentries = mm->context.tsb_block[MM_TSB_HUGE].tsb_nentries;
112 if (tlb_type == cheetah_plus || tlb_type == hypervisor)
113 base = __pa(base);
David S. Miller37b3a8f2013-09-25 13:48:49 -0700114 __flush_tsb_one_entry(base, vaddr, REAL_HPAGE_SHIFT, nentries);
David S. Millerf36391d2013-04-19 17:26:26 -0400115 }
116#endif
117 spin_unlock_irqrestore(&mm->context.lock, flags);
118}
119
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800120#define HV_PGSZ_IDX_BASE HV_PGSZ_IDX_8K
121#define HV_PGSZ_MASK_BASE HV_PGSZ_MASK_8K
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800122
David Miller9e695d22012-10-08 16:34:29 -0700123#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800124#define HV_PGSZ_IDX_HUGE HV_PGSZ_IDX_4MB
125#define HV_PGSZ_MASK_HUGE HV_PGSZ_MASK_4MB
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800126#endif
127
128static void setup_tsb_params(struct mm_struct *mm, unsigned long tsb_idx, unsigned long tsb_bytes)
David S. Miller98c55842006-01-31 18:31:20 -0800129{
130 unsigned long tsb_reg, base, tsb_paddr;
131 unsigned long page_sz, tte;
132
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800133 mm->context.tsb_block[tsb_idx].tsb_nentries =
134 tsb_bytes / sizeof(struct tsb);
David S. Miller98c55842006-01-31 18:31:20 -0800135
136 base = TSBMAP_BASE;
David S. Millerc4bce902006-02-11 21:57:54 -0800137 tte = pgprot_val(PAGE_KERNEL_LOCKED);
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800138 tsb_paddr = __pa(mm->context.tsb_block[tsb_idx].tsb);
David S. Miller517af332006-02-01 15:55:21 -0800139 BUG_ON(tsb_paddr & (tsb_bytes - 1UL));
David S. Miller98c55842006-01-31 18:31:20 -0800140
141 /* Use the smallest page size that can map the whole TSB
142 * in one TLB entry.
143 */
144 switch (tsb_bytes) {
145 case 8192 << 0:
146 tsb_reg = 0x0UL;
147#ifdef DCACHE_ALIASING_POSSIBLE
148 base += (tsb_paddr & 8192);
149#endif
David S. Miller98c55842006-01-31 18:31:20 -0800150 page_sz = 8192;
151 break;
152
153 case 8192 << 1:
154 tsb_reg = 0x1UL;
David S. Miller98c55842006-01-31 18:31:20 -0800155 page_sz = 64 * 1024;
156 break;
157
158 case 8192 << 2:
159 tsb_reg = 0x2UL;
David S. Miller98c55842006-01-31 18:31:20 -0800160 page_sz = 64 * 1024;
161 break;
162
163 case 8192 << 3:
164 tsb_reg = 0x3UL;
David S. Miller98c55842006-01-31 18:31:20 -0800165 page_sz = 64 * 1024;
166 break;
167
168 case 8192 << 4:
169 tsb_reg = 0x4UL;
David S. Miller98c55842006-01-31 18:31:20 -0800170 page_sz = 512 * 1024;
171 break;
172
173 case 8192 << 5:
174 tsb_reg = 0x5UL;
David S. Miller98c55842006-01-31 18:31:20 -0800175 page_sz = 512 * 1024;
176 break;
177
178 case 8192 << 6:
179 tsb_reg = 0x6UL;
David S. Miller98c55842006-01-31 18:31:20 -0800180 page_sz = 512 * 1024;
181 break;
182
183 case 8192 << 7:
184 tsb_reg = 0x7UL;
David S. Miller98c55842006-01-31 18:31:20 -0800185 page_sz = 4 * 1024 * 1024;
186 break;
David S. Millerbd407912006-01-31 18:31:38 -0800187
188 default:
David S. Miller7e5766f2007-10-29 00:36:09 -0700189 printk(KERN_ERR "TSB[%s:%d]: Impossible TSB size %lu, killing process.\n",
190 current->comm, current->pid, tsb_bytes);
191 do_exit(SIGSEGV);
Joe Perches6cb79b32011-06-03 14:45:23 +0000192 }
David S. Millerc4bce902006-02-11 21:57:54 -0800193 tte |= pte_sz_bits(page_sz);
David S. Miller98c55842006-01-31 18:31:20 -0800194
David S. Miller618e9ed2006-02-09 17:21:53 -0800195 if (tlb_type == cheetah_plus || tlb_type == hypervisor) {
David S. Miller517af332006-02-01 15:55:21 -0800196 /* Physical mapping, no locked TLB entry for TSB. */
197 tsb_reg |= tsb_paddr;
David S. Miller98c55842006-01-31 18:31:20 -0800198
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800199 mm->context.tsb_block[tsb_idx].tsb_reg_val = tsb_reg;
200 mm->context.tsb_block[tsb_idx].tsb_map_vaddr = 0;
201 mm->context.tsb_block[tsb_idx].tsb_map_pte = 0;
David S. Miller517af332006-02-01 15:55:21 -0800202 } else {
203 tsb_reg |= base;
204 tsb_reg |= (tsb_paddr & (page_sz - 1UL));
205 tte |= (tsb_paddr & ~(page_sz - 1UL));
206
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800207 mm->context.tsb_block[tsb_idx].tsb_reg_val = tsb_reg;
208 mm->context.tsb_block[tsb_idx].tsb_map_vaddr = base;
209 mm->context.tsb_block[tsb_idx].tsb_map_pte = tte;
David S. Miller517af332006-02-01 15:55:21 -0800210 }
211
David S. Miller618e9ed2006-02-09 17:21:53 -0800212 /* Setup the Hypervisor TSB descriptor. */
213 if (tlb_type == hypervisor) {
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800214 struct hv_tsb_descr *hp = &mm->context.tsb_descr[tsb_idx];
David S. Miller618e9ed2006-02-09 17:21:53 -0800215
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800216 switch (tsb_idx) {
217 case MM_TSB_BASE:
218 hp->pgsz_idx = HV_PGSZ_IDX_BASE;
219 break;
David Miller9e695d22012-10-08 16:34:29 -0700220#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800221 case MM_TSB_HUGE:
222 hp->pgsz_idx = HV_PGSZ_IDX_HUGE;
223 break;
224#endif
David S. Miller618e9ed2006-02-09 17:21:53 -0800225 default:
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800226 BUG();
Joe Perches6cb79b32011-06-03 14:45:23 +0000227 }
David S. Miller618e9ed2006-02-09 17:21:53 -0800228 hp->assoc = 1;
229 hp->num_ttes = tsb_bytes / 16;
230 hp->ctx_idx = 0;
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800231 switch (tsb_idx) {
232 case MM_TSB_BASE:
233 hp->pgsz_mask = HV_PGSZ_MASK_BASE;
234 break;
David Miller9e695d22012-10-08 16:34:29 -0700235#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800236 case MM_TSB_HUGE:
237 hp->pgsz_mask = HV_PGSZ_MASK_HUGE;
238 break;
239#endif
David S. Miller618e9ed2006-02-09 17:21:53 -0800240 default:
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800241 BUG();
Joe Perches6cb79b32011-06-03 14:45:23 +0000242 }
David S. Miller618e9ed2006-02-09 17:21:53 -0800243 hp->tsb_base = tsb_paddr;
244 hp->resv = 0;
245 }
David S. Miller98c55842006-01-31 18:31:20 -0800246}
247
David S. Miller4dedbf82011-07-25 17:12:20 -0700248struct kmem_cache *pgtable_cache __read_mostly;
249
Christoph Lametere18b8902006-12-06 20:33:20 -0800250static struct kmem_cache *tsb_caches[8] __read_mostly;
David S. Miller9b4006d2006-03-18 18:12:42 -0800251
252static const char *tsb_cache_names[8] = {
253 "tsb_8KB",
254 "tsb_16KB",
255 "tsb_32KB",
256 "tsb_64KB",
257 "tsb_128KB",
258 "tsb_256KB",
259 "tsb_512KB",
260 "tsb_1MB",
261};
262
David Miller3a2cba92007-05-06 14:49:51 -0700263void __init pgtable_cache_init(void)
David S. Miller9b4006d2006-03-18 18:12:42 -0800264{
265 unsigned long i;
266
David S. Miller4dedbf82011-07-25 17:12:20 -0700267 pgtable_cache = kmem_cache_create("pgtable_cache",
268 PAGE_SIZE, PAGE_SIZE,
269 0,
270 _clear_page);
271 if (!pgtable_cache) {
272 prom_printf("pgtable_cache_init(): Could not create!\n");
273 prom_halt();
274 }
275
David S. Miller9b4006d2006-03-18 18:12:42 -0800276 for (i = 0; i < 8; i++) {
277 unsigned long size = 8192 << i;
278 const char *name = tsb_cache_names[i];
279
280 tsb_caches[i] = kmem_cache_create(name,
281 size, size,
Paul Mundt20c2df82007-07-20 10:11:58 +0900282 0, NULL);
David S. Miller9b4006d2006-03-18 18:12:42 -0800283 if (!tsb_caches[i]) {
284 prom_printf("Could not create %s cache\n", name);
285 prom_halt();
286 }
287 }
288}
289
David S. Miller08714202008-11-16 23:49:24 -0800290int sysctl_tsb_ratio = -2;
291
292static unsigned long tsb_size_to_rss_limit(unsigned long new_size)
293{
294 unsigned long num_ents = (new_size / sizeof(struct tsb));
295
296 if (sysctl_tsb_ratio < 0)
297 return num_ents - (num_ents >> -sysctl_tsb_ratio);
298 else
299 return num_ents + (num_ents >> sysctl_tsb_ratio);
300}
301
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800302/* When the RSS of an address space exceeds tsb_rss_limit for a TSB,
303 * do_sparc64_fault() invokes this routine to try and grow it.
David S. Miller7a1ac522006-03-16 02:02:32 -0800304 *
David S. Millerbd407912006-01-31 18:31:38 -0800305 * When we reach the maximum TSB size supported, we stick ~0UL into
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800306 * tsb_rss_limit for that TSB so the grow checks in do_sparc64_fault()
David S. Millerbd407912006-01-31 18:31:38 -0800307 * will not trigger any longer.
308 *
309 * The TSB can be anywhere from 8K to 1MB in size, in increasing powers
310 * of two. The TSB must be aligned to it's size, so f.e. a 512K TSB
David S. Millerb52439c2006-03-17 23:40:47 -0800311 * must be 512K aligned. It also must be physically contiguous, so we
312 * cannot use vmalloc().
David S. Millerbd407912006-01-31 18:31:38 -0800313 *
314 * The idea here is to grow the TSB when the RSS of the process approaches
315 * the number of entries that the current TSB can hold at once. Currently,
316 * we trigger when the RSS hits 3/4 of the TSB capacity.
317 */
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800318void tsb_grow(struct mm_struct *mm, unsigned long tsb_index, unsigned long rss)
David S. Millerbd407912006-01-31 18:31:38 -0800319{
320 unsigned long max_tsb_size = 1 * 1024 * 1024;
David S. Miller9b4006d2006-03-18 18:12:42 -0800321 unsigned long new_size, old_size, flags;
David S. Miller7a1ac522006-03-16 02:02:32 -0800322 struct tsb *old_tsb, *new_tsb;
David S. Miller9b4006d2006-03-18 18:12:42 -0800323 unsigned long new_cache_index, old_cache_index;
324 unsigned long new_rss_limit;
David S. Millerb52439c2006-03-17 23:40:47 -0800325 gfp_t gfp_flags;
David S. Millerbd407912006-01-31 18:31:38 -0800326
327 if (max_tsb_size > (PAGE_SIZE << MAX_ORDER))
328 max_tsb_size = (PAGE_SIZE << MAX_ORDER);
329
David S. Miller9b4006d2006-03-18 18:12:42 -0800330 new_cache_index = 0;
331 for (new_size = 8192; new_size < max_tsb_size; new_size <<= 1UL) {
David S. Miller08714202008-11-16 23:49:24 -0800332 new_rss_limit = tsb_size_to_rss_limit(new_size);
333 if (new_rss_limit > rss)
David S. Millerbd407912006-01-31 18:31:38 -0800334 break;
David S. Miller9b4006d2006-03-18 18:12:42 -0800335 new_cache_index++;
David S. Millerbd407912006-01-31 18:31:38 -0800336 }
337
David S. Miller9b4006d2006-03-18 18:12:42 -0800338 if (new_size == max_tsb_size)
David S. Millerb52439c2006-03-17 23:40:47 -0800339 new_rss_limit = ~0UL;
David S. Millerb52439c2006-03-17 23:40:47 -0800340
David S. Miller9b4006d2006-03-18 18:12:42 -0800341retry_tsb_alloc:
David S. Millerb52439c2006-03-17 23:40:47 -0800342 gfp_flags = GFP_KERNEL;
David S. Miller9b4006d2006-03-18 18:12:42 -0800343 if (new_size > (PAGE_SIZE * 2))
David S. Millera55ee1f2013-02-19 12:56:18 -0800344 gfp_flags |= __GFP_NOWARN | __GFP_NORETRY;
David S. Millerb52439c2006-03-17 23:40:47 -0800345
David S. Miller1f261ef2008-03-19 04:53:58 -0700346 new_tsb = kmem_cache_alloc_node(tsb_caches[new_cache_index],
347 gfp_flags, numa_node_id());
David S. Miller9b4006d2006-03-18 18:12:42 -0800348 if (unlikely(!new_tsb)) {
David S. Millerb52439c2006-03-17 23:40:47 -0800349 /* Not being able to fork due to a high-order TSB
350 * allocation failure is very bad behavior. Just back
351 * down to a 0-order allocation and force no TSB
352 * growing for this address space.
353 */
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800354 if (mm->context.tsb_block[tsb_index].tsb == NULL &&
355 new_cache_index > 0) {
David S. Miller9b4006d2006-03-18 18:12:42 -0800356 new_cache_index = 0;
357 new_size = 8192;
David S. Millerb52439c2006-03-17 23:40:47 -0800358 new_rss_limit = ~0UL;
David S. Miller9b4006d2006-03-18 18:12:42 -0800359 goto retry_tsb_alloc;
David S. Millerb52439c2006-03-17 23:40:47 -0800360 }
361
362 /* If we failed on a TSB grow, we are under serious
363 * memory pressure so don't try to grow any more.
364 */
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800365 if (mm->context.tsb_block[tsb_index].tsb != NULL)
366 mm->context.tsb_block[tsb_index].tsb_rss_limit = ~0UL;
David S. Millerbd407912006-01-31 18:31:38 -0800367 return;
David S. Millerb52439c2006-03-17 23:40:47 -0800368 }
David S. Millerbd407912006-01-31 18:31:38 -0800369
David S. Miller8b234272006-02-17 18:01:02 -0800370 /* Mark all tags as invalid. */
David S. Millerbb8646d2006-03-18 23:55:11 -0800371 tsb_init(new_tsb, new_size);
David S. Miller7a1ac522006-03-16 02:02:32 -0800372
373 /* Ok, we are about to commit the changes. If we are
374 * growing an existing TSB the locking is very tricky,
375 * so WATCH OUT!
376 *
377 * We have to hold mm->context.lock while committing to the
378 * new TSB, this synchronizes us with processors in
379 * flush_tsb_user() and switch_mm() for this address space.
380 *
381 * But even with that lock held, processors run asynchronously
382 * accessing the old TSB via TLB miss handling. This is OK
383 * because those actions are just propagating state from the
384 * Linux page tables into the TSB, page table mappings are not
385 * being changed. If a real fault occurs, the processor will
386 * synchronize with us when it hits flush_tsb_user(), this is
387 * also true for the case where vmscan is modifying the page
388 * tables. The only thing we need to be careful with is to
389 * skip any locked TSB entries during copy_tsb().
390 *
391 * When we finish committing to the new TSB, we have to drop
392 * the lock and ask all other cpus running this address space
393 * to run tsb_context_switch() to see the new TSB table.
394 */
395 spin_lock_irqsave(&mm->context.lock, flags);
396
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800397 old_tsb = mm->context.tsb_block[tsb_index].tsb;
398 old_cache_index =
399 (mm->context.tsb_block[tsb_index].tsb_reg_val & 0x7UL);
400 old_size = (mm->context.tsb_block[tsb_index].tsb_nentries *
401 sizeof(struct tsb));
David S. Miller7a1ac522006-03-16 02:02:32 -0800402
David S. Miller9b4006d2006-03-18 18:12:42 -0800403
David S. Miller7a1ac522006-03-16 02:02:32 -0800404 /* Handle multiple threads trying to grow the TSB at the same time.
405 * One will get in here first, and bump the size and the RSS limit.
406 * The others will get in here next and hit this check.
407 */
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800408 if (unlikely(old_tsb &&
409 (rss < mm->context.tsb_block[tsb_index].tsb_rss_limit))) {
David S. Miller7a1ac522006-03-16 02:02:32 -0800410 spin_unlock_irqrestore(&mm->context.lock, flags);
411
David S. Miller9b4006d2006-03-18 18:12:42 -0800412 kmem_cache_free(tsb_caches[new_cache_index], new_tsb);
David S. Miller7a1ac522006-03-16 02:02:32 -0800413 return;
414 }
David S. Miller8b234272006-02-17 18:01:02 -0800415
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800416 mm->context.tsb_block[tsb_index].tsb_rss_limit = new_rss_limit;
David S. Millerbd407912006-01-31 18:31:38 -0800417
David S. Miller7a1ac522006-03-16 02:02:32 -0800418 if (old_tsb) {
419 extern void copy_tsb(unsigned long old_tsb_base,
420 unsigned long old_tsb_size,
421 unsigned long new_tsb_base,
422 unsigned long new_tsb_size);
423 unsigned long old_tsb_base = (unsigned long) old_tsb;
424 unsigned long new_tsb_base = (unsigned long) new_tsb;
David S. Millerbd407912006-01-31 18:31:38 -0800425
David S. Miller7a1ac522006-03-16 02:02:32 -0800426 if (tlb_type == cheetah_plus || tlb_type == hypervisor) {
427 old_tsb_base = __pa(old_tsb_base);
428 new_tsb_base = __pa(new_tsb_base);
429 }
David S. Miller9b4006d2006-03-18 18:12:42 -0800430 copy_tsb(old_tsb_base, old_size, new_tsb_base, new_size);
David S. Miller7a1ac522006-03-16 02:02:32 -0800431 }
David S. Millerbd407912006-01-31 18:31:38 -0800432
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800433 mm->context.tsb_block[tsb_index].tsb = new_tsb;
434 setup_tsb_params(mm, tsb_index, new_size);
David S. Millerbd407912006-01-31 18:31:38 -0800435
David S. Miller7a1ac522006-03-16 02:02:32 -0800436 spin_unlock_irqrestore(&mm->context.lock, flags);
437
David S. Millerbd407912006-01-31 18:31:38 -0800438 /* If old_tsb is NULL, we're being invoked for the first time
439 * from init_new_context().
440 */
441 if (old_tsb) {
David S. Miller7a1ac522006-03-16 02:02:32 -0800442 /* Reload it on the local cpu. */
David S. Millerbd407912006-01-31 18:31:38 -0800443 tsb_context_switch(mm);
444
David S. Miller7a1ac522006-03-16 02:02:32 -0800445 /* Now force other processors to do the same. */
David S. Millera3cf5e62008-08-03 00:01:05 -0700446 preempt_disable();
David S. Miller7a1ac522006-03-16 02:02:32 -0800447 smp_tsb_sync(mm);
David S. Millera3cf5e62008-08-03 00:01:05 -0700448 preempt_enable();
David S. Miller7a1ac522006-03-16 02:02:32 -0800449
450 /* Now it is safe to free the old tsb. */
David S. Miller9b4006d2006-03-18 18:12:42 -0800451 kmem_cache_free(tsb_caches[old_cache_index], old_tsb);
David S. Millerbd407912006-01-31 18:31:38 -0800452 }
453}
454
David S. Miller09f94282006-01-31 18:31:06 -0800455int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
456{
David Miller9e695d22012-10-08 16:34:29 -0700457#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800458 unsigned long huge_pte_count;
459#endif
460 unsigned int i;
461
David S. Millera77754b2006-03-06 19:59:50 -0800462 spin_lock_init(&mm->context.lock);
David S. Miller09f94282006-01-31 18:31:06 -0800463
464 mm->context.sparc64_ctx_val = 0UL;
David S. Miller09f94282006-01-31 18:31:06 -0800465
David Miller9e695d22012-10-08 16:34:29 -0700466#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800467 /* We reset it to zero because the fork() page copying
468 * will re-increment the counters as the parent PTEs are
469 * copied into the child address space.
470 */
471 huge_pte_count = mm->context.huge_pte_count;
472 mm->context.huge_pte_count = 0;
473#endif
474
David S. Millerbd407912006-01-31 18:31:38 -0800475 /* copy_mm() copies over the parent's mm_struct before calling
476 * us, so we need to zero out the TSB pointer or else tsb_grow()
477 * will be confused and think there is an older TSB to free up.
478 */
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800479 for (i = 0; i < MM_NUM_TSBS; i++)
480 mm->context.tsb_block[i].tsb = NULL;
David S. Miller7a1ac522006-03-16 02:02:32 -0800481
482 /* If this is fork, inherit the parent's TSB size. We would
483 * grow it to that size on the first page fault anyways.
484 */
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800485 tsb_grow(mm, MM_TSB_BASE, get_mm_rss(mm));
David S. Millerbd407912006-01-31 18:31:38 -0800486
David Miller9e695d22012-10-08 16:34:29 -0700487#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800488 if (unlikely(huge_pte_count))
489 tsb_grow(mm, MM_TSB_HUGE, huge_pte_count);
490#endif
491
492 if (unlikely(!mm->context.tsb_block[MM_TSB_BASE].tsb))
David S. Millerbd407912006-01-31 18:31:38 -0800493 return -ENOMEM;
David S. Miller09f94282006-01-31 18:31:06 -0800494
495 return 0;
496}
497
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800498static void tsb_destroy_one(struct tsb_config *tp)
499{
500 unsigned long cache_index;
501
502 if (!tp->tsb)
503 return;
504 cache_index = tp->tsb_reg_val & 0x7UL;
505 kmem_cache_free(tsb_caches[cache_index], tp->tsb);
506 tp->tsb = NULL;
507 tp->tsb_reg_val = 0UL;
508}
509
David S. Miller09f94282006-01-31 18:31:06 -0800510void destroy_context(struct mm_struct *mm)
511{
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800512 unsigned long flags, i;
David S. Millerbd407912006-01-31 18:31:38 -0800513
David S. Millerdcc1e8d2006-03-22 00:49:59 -0800514 for (i = 0; i < MM_NUM_TSBS; i++)
515 tsb_destroy_one(&mm->context.tsb_block[i]);
David S. Miller09f94282006-01-31 18:31:06 -0800516
David S. Miller77b838f2006-02-23 21:40:15 -0800517 spin_lock_irqsave(&ctx_alloc_lock, flags);
David S. Miller09f94282006-01-31 18:31:06 -0800518
519 if (CTX_VALID(mm->context)) {
520 unsigned long nr = CTX_NRBITS(mm->context);
521 mmu_context_bmap[nr>>6] &= ~(1UL << (nr & 63));
522 }
523
David S. Miller77b838f2006-02-23 21:40:15 -0800524 spin_unlock_irqrestore(&ctx_alloc_lock, flags);
David S. Miller09f94282006-01-31 18:31:06 -0800525}