]>
Commit | Line | Data |
---|---|---|
aa04b4cc PM |
1 | /* |
2 | * Copyright 2011 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of the GNU General Public License, version 2, as | |
6 | * published by the Free Software Foundation. | |
7 | */ | |
8 | ||
441c19c8 | 9 | #include <linux/cpu.h> |
aa04b4cc PM |
10 | #include <linux/kvm_host.h> |
11 | #include <linux/preempt.h> | |
66b15db6 | 12 | #include <linux/export.h> |
aa04b4cc PM |
13 | #include <linux/sched.h> |
14 | #include <linux/spinlock.h> | |
aa04b4cc | 15 | #include <linux/init.h> |
fa61a4e3 AK |
16 | #include <linux/memblock.h> |
17 | #include <linux/sizes.h> | |
fc95ca72 | 18 | #include <linux/cma.h> |
90fd09f8 | 19 | #include <linux/bitops.h> |
aa04b4cc PM |
20 | |
21 | #include <asm/cputable.h> | |
22 | #include <asm/kvm_ppc.h> | |
23 | #include <asm/kvm_book3s.h> | |
e928e9cb | 24 | #include <asm/archrandom.h> |
eddb60fb | 25 | #include <asm/xics.h> |
66feed61 PM |
26 | #include <asm/dbell.h> |
27 | #include <asm/cputhreads.h> | |
37f55d30 | 28 | #include <asm/io.h> |
f725758b | 29 | #include <asm/opal.h> |
e2702871 | 30 | #include <asm/smp.h> |
aa04b4cc | 31 | |
53af3ba2 PM |
32 | static bool in_realmode(void) |
33 | { | |
34 | return !(mfmsr() & MSR_IR); | |
35 | } | |
36 | ||
fc95ca72 JK |
37 | #define KVM_CMA_CHUNK_ORDER 18 |
38 | ||
fa61a4e3 AK |
39 | /* |
40 | * Hash page table alignment on newer cpus(CPU_FTR_ARCH_206) | |
41 | * should be power of 2. | |
42 | */ | |
43 | #define HPT_ALIGN_PAGES ((1 << 18) >> PAGE_SHIFT) /* 256k */ | |
44 | /* | |
45 | * By default we reserve 5% of memory for hash pagetable allocation. | |
46 | */ | |
47 | static unsigned long kvm_cma_resv_ratio = 5; | |
aa04b4cc | 48 | |
fc95ca72 JK |
49 | static struct cma *kvm_cma; |
50 | ||
fa61a4e3 | 51 | static int __init early_parse_kvm_cma_resv(char *p) |
d2a1b483 | 52 | { |
fa61a4e3 | 53 | pr_debug("%s(%s)\n", __func__, p); |
d2a1b483 | 54 | if (!p) |
fa61a4e3 AK |
55 | return -EINVAL; |
56 | return kstrtoul(p, 0, &kvm_cma_resv_ratio); | |
d2a1b483 | 57 | } |
fa61a4e3 | 58 | early_param("kvm_cma_resv_ratio", early_parse_kvm_cma_resv); |
d2a1b483 | 59 | |
fa61a4e3 | 60 | struct page *kvm_alloc_hpt(unsigned long nr_pages) |
d2a1b483 | 61 | { |
c04fa583 | 62 | VM_BUG_ON(order_base_2(nr_pages) < KVM_CMA_CHUNK_ORDER - PAGE_SHIFT); |
fc95ca72 | 63 | |
c17b98cf | 64 | return cma_alloc(kvm_cma, nr_pages, order_base_2(HPT_ALIGN_PAGES)); |
d2a1b483 AG |
65 | } |
66 | EXPORT_SYMBOL_GPL(kvm_alloc_hpt); | |
67 | ||
fa61a4e3 | 68 | void kvm_release_hpt(struct page *page, unsigned long nr_pages) |
d2a1b483 | 69 | { |
fc95ca72 | 70 | cma_release(kvm_cma, page, nr_pages); |
d2a1b483 AG |
71 | } |
72 | EXPORT_SYMBOL_GPL(kvm_release_hpt); | |
73 | ||
fa61a4e3 AK |
74 | /** |
75 | * kvm_cma_reserve() - reserve area for kvm hash pagetable | |
76 | * | |
77 | * This function reserves memory from early allocator. It should be | |
14ed7409 | 78 | * called by arch specific code once the memblock allocator |
fa61a4e3 AK |
79 | * has been activated and all other subsystems have already allocated/reserved |
80 | * memory. | |
81 | */ | |
82 | void __init kvm_cma_reserve(void) | |
83 | { | |
84 | unsigned long align_size; | |
85 | struct memblock_region *reg; | |
86 | phys_addr_t selected_size = 0; | |
cec26bc3 AK |
87 | |
88 | /* | |
89 | * We need CMA reservation only when we are in HV mode | |
90 | */ | |
91 | if (!cpu_has_feature(CPU_FTR_HVMODE)) | |
92 | return; | |
fa61a4e3 AK |
93 | /* |
94 | * We cannot use memblock_phys_mem_size() here, because | |
95 | * memblock_analyze() has not been called yet. | |
96 | */ | |
97 | for_each_memblock(memory, reg) | |
98 | selected_size += memblock_region_memory_end_pfn(reg) - | |
99 | memblock_region_memory_base_pfn(reg); | |
100 | ||
101 | selected_size = (selected_size * kvm_cma_resv_ratio / 100) << PAGE_SHIFT; | |
102 | if (selected_size) { | |
103 | pr_debug("%s: reserving %ld MiB for global area\n", __func__, | |
104 | (unsigned long)selected_size / SZ_1M); | |
c17b98cf | 105 | align_size = HPT_ALIGN_PAGES << PAGE_SHIFT; |
c1f733aa JK |
106 | cma_declare_contiguous(0, selected_size, 0, align_size, |
107 | KVM_CMA_CHUNK_ORDER - PAGE_SHIFT, false, &kvm_cma); | |
fa61a4e3 AK |
108 | } |
109 | } | |
441c19c8 | 110 | |
90fd09f8 SB |
111 | /* |
112 | * Real-mode H_CONFER implementation. | |
113 | * We check if we are the only vcpu out of this virtual core | |
114 | * still running in the guest and not ceded. If so, we pop up | |
115 | * to the virtual-mode implementation; if not, just return to | |
116 | * the guest. | |
117 | */ | |
118 | long int kvmppc_rm_h_confer(struct kvm_vcpu *vcpu, int target, | |
119 | unsigned int yield_count) | |
120 | { | |
ec257165 PM |
121 | struct kvmppc_vcore *vc = local_paca->kvm_hstate.kvm_vcore; |
122 | int ptid = local_paca->kvm_hstate.ptid; | |
90fd09f8 SB |
123 | int threads_running; |
124 | int threads_ceded; | |
125 | int threads_conferring; | |
126 | u64 stop = get_tb() + 10 * tb_ticks_per_usec; | |
127 | int rv = H_SUCCESS; /* => don't yield */ | |
128 | ||
ec257165 | 129 | set_bit(ptid, &vc->conferring_threads); |
7d6c40da PM |
130 | while ((get_tb() < stop) && !VCORE_IS_EXITING(vc)) { |
131 | threads_running = VCORE_ENTRY_MAP(vc); | |
132 | threads_ceded = vc->napping_threads; | |
133 | threads_conferring = vc->conferring_threads; | |
134 | if ((threads_ceded | threads_conferring) == threads_running) { | |
90fd09f8 SB |
135 | rv = H_TOO_HARD; /* => do yield */ |
136 | break; | |
137 | } | |
138 | } | |
ec257165 | 139 | clear_bit(ptid, &vc->conferring_threads); |
90fd09f8 SB |
140 | return rv; |
141 | } | |
142 | ||
441c19c8 ME |
143 | /* |
144 | * When running HV mode KVM we need to block certain operations while KVM VMs | |
145 | * exist in the system. We use a counter of VMs to track this. | |
146 | * | |
147 | * One of the operations we need to block is onlining of secondaries, so we | |
148 | * protect hv_vm_count with get/put_online_cpus(). | |
149 | */ | |
150 | static atomic_t hv_vm_count; | |
151 | ||
152 | void kvm_hv_vm_activated(void) | |
153 | { | |
154 | get_online_cpus(); | |
155 | atomic_inc(&hv_vm_count); | |
156 | put_online_cpus(); | |
157 | } | |
158 | EXPORT_SYMBOL_GPL(kvm_hv_vm_activated); | |
159 | ||
160 | void kvm_hv_vm_deactivated(void) | |
161 | { | |
162 | get_online_cpus(); | |
163 | atomic_dec(&hv_vm_count); | |
164 | put_online_cpus(); | |
165 | } | |
166 | EXPORT_SYMBOL_GPL(kvm_hv_vm_deactivated); | |
167 | ||
168 | bool kvm_hv_mode_active(void) | |
169 | { | |
170 | return atomic_read(&hv_vm_count) != 0; | |
171 | } | |
ae2113a4 PM |
172 | |
173 | extern int hcall_real_table[], hcall_real_table_end[]; | |
174 | ||
175 | int kvmppc_hcall_impl_hv_realmode(unsigned long cmd) | |
176 | { | |
177 | cmd /= 4; | |
178 | if (cmd < hcall_real_table_end - hcall_real_table && | |
179 | hcall_real_table[cmd]) | |
180 | return 1; | |
181 | ||
182 | return 0; | |
183 | } | |
184 | EXPORT_SYMBOL_GPL(kvmppc_hcall_impl_hv_realmode); | |
e928e9cb ME |
185 | |
186 | int kvmppc_hwrng_present(void) | |
187 | { | |
188 | return powernv_hwrng_present(); | |
189 | } | |
190 | EXPORT_SYMBOL_GPL(kvmppc_hwrng_present); | |
191 | ||
192 | long kvmppc_h_random(struct kvm_vcpu *vcpu) | |
193 | { | |
194 | if (powernv_get_random_real_mode(&vcpu->arch.gpr[4])) | |
195 | return H_SUCCESS; | |
196 | ||
197 | return H_HARDWARE; | |
198 | } | |
eddb60fb PM |
199 | |
200 | static inline void rm_writeb(unsigned long paddr, u8 val) | |
201 | { | |
202 | __asm__ __volatile__("stbcix %0,0,%1" | |
203 | : : "r" (val), "r" (paddr) : "memory"); | |
204 | } | |
205 | ||
206 | /* | |
66feed61 | 207 | * Send an interrupt or message to another CPU. |
eddb60fb PM |
208 | * The caller needs to include any barrier needed to order writes |
209 | * to memory vs. the IPI/message. | |
210 | */ | |
211 | void kvmhv_rm_send_ipi(int cpu) | |
212 | { | |
213 | unsigned long xics_phys; | |
1704a81c | 214 | unsigned long msg = PPC_DBELL_TYPE(PPC_DBELL_SERVER); |
eddb60fb | 215 | |
1704a81c PM |
216 | /* On POWER9 we can use msgsnd for any destination cpu. */ |
217 | if (cpu_has_feature(CPU_FTR_ARCH_300)) { | |
218 | msg |= get_hard_smp_processor_id(cpu); | |
219 | __asm__ __volatile__ (PPC_MSGSND(%0) : : "r" (msg)); | |
220 | return; | |
221 | } | |
222 | /* On POWER8 for IPIs to threads in the same core, use msgsnd. */ | |
66feed61 PM |
223 | if (cpu_has_feature(CPU_FTR_ARCH_207S) && |
224 | cpu_first_thread_sibling(cpu) == | |
225 | cpu_first_thread_sibling(raw_smp_processor_id())) { | |
66feed61 PM |
226 | msg |= cpu_thread_in_core(cpu); |
227 | __asm__ __volatile__ (PPC_MSGSND(%0) : : "r" (msg)); | |
228 | return; | |
229 | } | |
230 | ||
231 | /* Else poke the target with an IPI */ | |
eddb60fb | 232 | xics_phys = paca[cpu].kvm_hstate.xics_phys; |
53af3ba2 PM |
233 | if (!in_realmode()) |
234 | opal_int_set_mfrr(get_hard_smp_processor_id(cpu), IPI_PRIORITY); | |
235 | else if (xics_phys) | |
f725758b PM |
236 | rm_writeb(xics_phys + XICS_MFRR, IPI_PRIORITY); |
237 | else | |
238 | opal_rm_int_set_mfrr(get_hard_smp_processor_id(cpu), | |
239 | IPI_PRIORITY); | |
eddb60fb PM |
240 | } |
241 | ||
242 | /* | |
243 | * The following functions are called from the assembly code | |
244 | * in book3s_hv_rmhandlers.S. | |
245 | */ | |
246 | static void kvmhv_interrupt_vcore(struct kvmppc_vcore *vc, int active) | |
247 | { | |
248 | int cpu = vc->pcpu; | |
249 | ||
250 | /* Order setting of exit map vs. msgsnd/IPI */ | |
251 | smp_mb(); | |
252 | for (; active; active >>= 1, ++cpu) | |
253 | if (active & 1) | |
254 | kvmhv_rm_send_ipi(cpu); | |
255 | } | |
256 | ||
257 | void kvmhv_commence_exit(int trap) | |
258 | { | |
259 | struct kvmppc_vcore *vc = local_paca->kvm_hstate.kvm_vcore; | |
260 | int ptid = local_paca->kvm_hstate.ptid; | |
b4deba5c PM |
261 | struct kvm_split_mode *sip = local_paca->kvm_hstate.kvm_split_mode; |
262 | int me, ee, i; | |
eddb60fb PM |
263 | |
264 | /* Set our bit in the threads-exiting-guest map in the 0xff00 | |
265 | bits of vcore->entry_exit_map */ | |
266 | me = 0x100 << ptid; | |
267 | do { | |
268 | ee = vc->entry_exit_map; | |
269 | } while (cmpxchg(&vc->entry_exit_map, ee, ee | me) != ee); | |
270 | ||
271 | /* Are we the first here? */ | |
272 | if ((ee >> 8) != 0) | |
273 | return; | |
274 | ||
275 | /* | |
276 | * Trigger the other threads in this vcore to exit the guest. | |
277 | * If this is a hypervisor decrementer interrupt then they | |
278 | * will be already on their way out of the guest. | |
279 | */ | |
280 | if (trap != BOOK3S_INTERRUPT_HV_DECREMENTER) | |
281 | kvmhv_interrupt_vcore(vc, ee & ~(1 << ptid)); | |
b4deba5c PM |
282 | |
283 | /* | |
284 | * If we are doing dynamic micro-threading, interrupt the other | |
285 | * subcores to pull them out of their guests too. | |
286 | */ | |
287 | if (!sip) | |
288 | return; | |
289 | ||
290 | for (i = 0; i < MAX_SUBCORES; ++i) { | |
291 | vc = sip->master_vcs[i]; | |
292 | if (!vc) | |
293 | break; | |
294 | do { | |
295 | ee = vc->entry_exit_map; | |
296 | /* Already asked to exit? */ | |
297 | if ((ee >> 8) != 0) | |
298 | break; | |
299 | } while (cmpxchg(&vc->entry_exit_map, ee, | |
300 | ee | VCORE_EXIT_REQ) != ee); | |
301 | if ((ee >> 8) == 0) | |
302 | kvmhv_interrupt_vcore(vc, ee); | |
303 | } | |
eddb60fb | 304 | } |
79b6c247 SW |
305 | |
306 | struct kvmppc_host_rm_ops *kvmppc_host_rm_ops_hv; | |
307 | EXPORT_SYMBOL_GPL(kvmppc_host_rm_ops_hv); | |
37f55d30 | 308 | |
e3c13e56 SW |
309 | #ifdef CONFIG_KVM_XICS |
310 | static struct kvmppc_irq_map *get_irqmap(struct kvmppc_passthru_irqmap *pimap, | |
311 | u32 xisr) | |
312 | { | |
313 | int i; | |
314 | ||
315 | /* | |
316 | * We access the mapped array here without a lock. That | |
317 | * is safe because we never reduce the number of entries | |
318 | * in the array and we never change the v_hwirq field of | |
319 | * an entry once it is set. | |
320 | * | |
321 | * We have also carefully ordered the stores in the writer | |
322 | * and the loads here in the reader, so that if we find a matching | |
323 | * hwirq here, the associated GSI and irq_desc fields are valid. | |
324 | */ | |
325 | for (i = 0; i < pimap->n_mapped; i++) { | |
326 | if (xisr == pimap->mapped[i].r_hwirq) { | |
327 | /* | |
328 | * Order subsequent reads in the caller to serialize | |
329 | * with the writer. | |
330 | */ | |
331 | smp_rmb(); | |
332 | return &pimap->mapped[i]; | |
333 | } | |
334 | } | |
335 | return NULL; | |
336 | } | |
337 | ||
338 | /* | |
339 | * If we have an interrupt that's not an IPI, check if we have a | |
340 | * passthrough adapter and if so, check if this external interrupt | |
341 | * is for the adapter. | |
342 | * We will attempt to deliver the IRQ directly to the target VCPU's | |
343 | * ICP, the virtual ICP (based on affinity - the xive value in ICS). | |
344 | * | |
345 | * If the delivery fails or if this is not for a passthrough adapter, | |
346 | * return to the host to handle this interrupt. We earlier | |
347 | * saved a copy of the XIRR in the PACA, it will be picked up by | |
348 | * the host ICP driver. | |
349 | */ | |
f725758b | 350 | static int kvmppc_check_passthru(u32 xisr, __be32 xirr, bool *again) |
e3c13e56 SW |
351 | { |
352 | struct kvmppc_passthru_irqmap *pimap; | |
353 | struct kvmppc_irq_map *irq_map; | |
354 | struct kvm_vcpu *vcpu; | |
355 | ||
356 | vcpu = local_paca->kvm_hstate.kvm_vcpu; | |
357 | if (!vcpu) | |
358 | return 1; | |
359 | pimap = kvmppc_get_passthru_irqmap(vcpu->kvm); | |
360 | if (!pimap) | |
361 | return 1; | |
362 | irq_map = get_irqmap(pimap, xisr); | |
363 | if (!irq_map) | |
364 | return 1; | |
365 | ||
366 | /* We're handling this interrupt, generic code doesn't need to */ | |
367 | local_paca->kvm_hstate.saved_xirr = 0; | |
368 | ||
f725758b | 369 | return kvmppc_deliver_irq_passthru(vcpu, xirr, irq_map, pimap, again); |
e3c13e56 SW |
370 | } |
371 | ||
372 | #else | |
e2702871 | 373 | static inline int kvmppc_check_passthru(u32 xisr, __be32 xirr, bool *again) |
e3c13e56 SW |
374 | { |
375 | return 1; | |
376 | } | |
377 | #endif | |
378 | ||
37f55d30 SW |
379 | /* |
380 | * Determine what sort of external interrupt is pending (if any). | |
381 | * Returns: | |
382 | * 0 if no interrupt is pending | |
383 | * 1 if an interrupt is pending that needs to be handled by the host | |
f7af5209 | 384 | * 2 Passthrough that needs completion in the host |
37f55d30 | 385 | * -1 if there was a guest wakeup IPI (which has now been cleared) |
e3c13e56 | 386 | * -2 if there is PCI passthrough external interrupt that was handled |
37f55d30 | 387 | */ |
f725758b | 388 | static long kvmppc_read_one_intr(bool *again); |
37f55d30 SW |
389 | |
390 | long kvmppc_read_intr(void) | |
f725758b PM |
391 | { |
392 | long ret = 0; | |
393 | long rc; | |
394 | bool again; | |
395 | ||
396 | do { | |
397 | again = false; | |
398 | rc = kvmppc_read_one_intr(&again); | |
399 | if (rc && (ret == 0 || rc > ret)) | |
400 | ret = rc; | |
401 | } while (again); | |
402 | return ret; | |
403 | } | |
404 | ||
405 | static long kvmppc_read_one_intr(bool *again) | |
37f55d30 SW |
406 | { |
407 | unsigned long xics_phys; | |
408 | u32 h_xirr; | |
409 | __be32 xirr; | |
410 | u32 xisr; | |
411 | u8 host_ipi; | |
f725758b | 412 | int64_t rc; |
37f55d30 SW |
413 | |
414 | /* see if a host IPI is pending */ | |
415 | host_ipi = local_paca->kvm_hstate.host_ipi; | |
416 | if (host_ipi) | |
417 | return 1; | |
418 | ||
419 | /* Now read the interrupt from the ICP */ | |
420 | xics_phys = local_paca->kvm_hstate.xics_phys; | |
53af3ba2 PM |
421 | rc = 0; |
422 | if (!in_realmode()) | |
423 | rc = opal_int_get_xirr(&xirr, false); | |
424 | else if (!xics_phys) | |
f725758b | 425 | rc = opal_rm_int_get_xirr(&xirr, false); |
53af3ba2 | 426 | else |
f725758b | 427 | xirr = _lwzcix(xics_phys + XICS_XIRR); |
53af3ba2 PM |
428 | if (rc < 0) |
429 | return 1; | |
37f55d30 SW |
430 | |
431 | /* | |
432 | * Save XIRR for later. Since we get control in reverse endian | |
433 | * on LE systems, save it byte reversed and fetch it back in | |
434 | * host endian. Note that xirr is the value read from the | |
435 | * XIRR register, while h_xirr is the host endian version. | |
436 | */ | |
37f55d30 SW |
437 | h_xirr = be32_to_cpu(xirr); |
438 | local_paca->kvm_hstate.saved_xirr = h_xirr; | |
439 | xisr = h_xirr & 0xffffff; | |
440 | /* | |
441 | * Ensure that the store/load complete to guarantee all side | |
442 | * effects of loading from XIRR has completed | |
443 | */ | |
444 | smp_mb(); | |
445 | ||
446 | /* if nothing pending in the ICP */ | |
447 | if (!xisr) | |
448 | return 0; | |
449 | ||
450 | /* We found something in the ICP... | |
451 | * | |
452 | * If it is an IPI, clear the MFRR and EOI it. | |
453 | */ | |
454 | if (xisr == XICS_IPI) { | |
53af3ba2 PM |
455 | rc = 0; |
456 | if (!in_realmode()) { | |
457 | opal_int_set_mfrr(hard_smp_processor_id(), 0xff); | |
458 | rc = opal_int_eoi(h_xirr); | |
459 | } else if (xics_phys) { | |
f725758b PM |
460 | _stbcix(xics_phys + XICS_MFRR, 0xff); |
461 | _stwcix(xics_phys + XICS_XIRR, xirr); | |
462 | } else { | |
463 | opal_rm_int_set_mfrr(hard_smp_processor_id(), 0xff); | |
464 | rc = opal_rm_int_eoi(h_xirr); | |
f725758b | 465 | } |
53af3ba2 PM |
466 | /* If rc > 0, there is another interrupt pending */ |
467 | *again = rc > 0; | |
f725758b | 468 | |
37f55d30 SW |
469 | /* |
470 | * Need to ensure side effects of above stores | |
471 | * complete before proceeding. | |
472 | */ | |
473 | smp_mb(); | |
474 | ||
475 | /* | |
476 | * We need to re-check host IPI now in case it got set in the | |
477 | * meantime. If it's clear, we bounce the interrupt to the | |
478 | * guest | |
479 | */ | |
480 | host_ipi = local_paca->kvm_hstate.host_ipi; | |
481 | if (unlikely(host_ipi != 0)) { | |
482 | /* We raced with the host, | |
483 | * we need to resend that IPI, bummer | |
484 | */ | |
53af3ba2 PM |
485 | if (!in_realmode()) |
486 | opal_int_set_mfrr(hard_smp_processor_id(), | |
487 | IPI_PRIORITY); | |
488 | else if (xics_phys) | |
f725758b PM |
489 | _stbcix(xics_phys + XICS_MFRR, IPI_PRIORITY); |
490 | else | |
491 | opal_rm_int_set_mfrr(hard_smp_processor_id(), | |
492 | IPI_PRIORITY); | |
37f55d30 SW |
493 | /* Let side effects complete */ |
494 | smp_mb(); | |
495 | return 1; | |
496 | } | |
497 | ||
498 | /* OK, it's an IPI for us */ | |
499 | local_paca->kvm_hstate.saved_xirr = 0; | |
500 | return -1; | |
501 | } | |
502 | ||
f725758b | 503 | return kvmppc_check_passthru(xisr, xirr, again); |
37f55d30 | 504 | } |