KVM: PPC: Add return value to core_check_requests
[deliverable/linux.git] / arch / powerpc / include / asm / kvm_host.h
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1/*
2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License, version 2, as
4 * published by the Free Software Foundation.
5 *
6 * This program is distributed in the hope that it will be useful,
7 * but WITHOUT ANY WARRANTY; without even the implied warranty of
8 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
9 * GNU General Public License for more details.
10 *
11 * You should have received a copy of the GNU General Public License
12 * along with this program; if not, write to the Free Software
13 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
14 *
15 * Copyright IBM Corp. 2007
16 *
17 * Authors: Hollis Blanchard <hollisb@us.ibm.com>
18 */
19
20#ifndef __POWERPC_KVM_HOST_H__
21#define __POWERPC_KVM_HOST_H__
22
23#include <linux/mutex.h>
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24#include <linux/hrtimer.h>
25#include <linux/interrupt.h>
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26#include <linux/types.h>
27#include <linux/kvm_types.h>
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28#include <linux/threads.h>
29#include <linux/spinlock.h>
96bc451a 30#include <linux/kvm_para.h>
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31#include <linux/list.h>
32#include <linux/atomic.h>
bbf45ba5 33#include <asm/kvm_asm.h>
371fefd6 34#include <asm/processor.h>
342d3db7 35#include <asm/page.h>
249ba1ee 36#include <asm/cacheflush.h>
bbf45ba5 37
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38#define KVM_MAX_VCPUS NR_CPUS
39#define KVM_MAX_VCORES NR_CPUS
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40#define KVM_MEMORY_SLOTS 32
41/* memory slots that does not exposed to userspace */
42#define KVM_PRIVATE_MEM_SLOTS 4
b2b2f165 43#define KVM_MEM_SLOTS_NUM (KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS)
bbf45ba5 44
de56a948 45#ifdef CONFIG_KVM_MMIO
588968b6 46#define KVM_COALESCED_MMIO_PAGE_OFFSET 1
de56a948 47#endif
588968b6 48
9b0cb3c8 49#if !defined(CONFIG_KVM_440)
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50#include <linux/mmu_notifier.h>
51
52#define KVM_ARCH_WANT_MMU_NOTIFIER
53
54struct kvm;
55extern int kvm_unmap_hva(struct kvm *kvm, unsigned long hva);
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56extern int kvm_unmap_hva_range(struct kvm *kvm,
57 unsigned long start, unsigned long end);
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58extern int kvm_age_hva(struct kvm *kvm, unsigned long hva);
59extern int kvm_test_age_hva(struct kvm *kvm, unsigned long hva);
60extern void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
61
62#endif
63
bbf45ba5 64/* We don't currently support large pages. */
82855413 65#define KVM_HPAGE_GFN_SHIFT(x) 0
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66#define KVM_NR_PAGE_SIZES 1
67#define KVM_PAGES_PER_HPAGE(x) (1UL<<31)
bbf45ba5 68
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69#define HPTEG_CACHE_NUM (1 << 15)
70#define HPTEG_HASH_BITS_PTE 13
2d27fc5e 71#define HPTEG_HASH_BITS_PTE_LONG 12
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72#define HPTEG_HASH_BITS_VPTE 13
73#define HPTEG_HASH_BITS_VPTE_LONG 5
74#define HPTEG_HASH_NUM_PTE (1 << HPTEG_HASH_BITS_PTE)
2d27fc5e 75#define HPTEG_HASH_NUM_PTE_LONG (1 << HPTEG_HASH_BITS_PTE_LONG)
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76#define HPTEG_HASH_NUM_VPTE (1 << HPTEG_HASH_BITS_VPTE)
77#define HPTEG_HASH_NUM_VPTE_LONG (1 << HPTEG_HASH_BITS_VPTE_LONG)
ca95150b 78
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79/* Physical Address Mask - allowed range of real mode RAM access */
80#define KVM_PAM 0x0fffffffffffffffULL
81
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82struct kvm;
83struct kvm_run;
84struct kvm_vcpu;
85
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86struct lppaca;
87struct slb_shadow;
2e25aa5f 88struct dtl_entry;
a8606e20 89
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90struct kvm_vm_stat {
91 u32 remote_tlb_flush;
92};
93
94struct kvm_vcpu_stat {
95 u32 sum_exits;
96 u32 mmio_exits;
97 u32 dcr_exits;
98 u32 signal_exits;
99 u32 light_exits;
100 /* Account for special types of light exits: */
101 u32 itlb_real_miss_exits;
102 u32 itlb_virt_miss_exits;
103 u32 dtlb_real_miss_exits;
104 u32 dtlb_virt_miss_exits;
105 u32 syscall_exits;
106 u32 isi_exits;
107 u32 dsi_exits;
108 u32 emulated_inst_exits;
109 u32 dec_exits;
110 u32 ext_intr_exits;
45c5eb67 111 u32 halt_wakeup;
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112 u32 dbell_exits;
113 u32 gdbell_exits;
00c3a37c 114#ifdef CONFIG_PPC_BOOK3S
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115 u32 pf_storage;
116 u32 pf_instruc;
117 u32 sp_storage;
118 u32 sp_instruc;
119 u32 queue_intr;
120 u32 ld;
121 u32 ld_slow;
122 u32 st;
123 u32 st_slow;
124#endif
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125};
126
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127enum kvm_exit_types {
128 MMIO_EXITS,
129 DCR_EXITS,
130 SIGNAL_EXITS,
131 ITLB_REAL_MISS_EXITS,
132 ITLB_VIRT_MISS_EXITS,
133 DTLB_REAL_MISS_EXITS,
134 DTLB_VIRT_MISS_EXITS,
135 SYSCALL_EXITS,
136 ISI_EXITS,
137 DSI_EXITS,
138 EMULATED_INST_EXITS,
139 EMULATED_MTMSRWE_EXITS,
140 EMULATED_WRTEE_EXITS,
141 EMULATED_MTSPR_EXITS,
142 EMULATED_MFSPR_EXITS,
143 EMULATED_MTMSR_EXITS,
144 EMULATED_MFMSR_EXITS,
145 EMULATED_TLBSX_EXITS,
146 EMULATED_TLBWE_EXITS,
147 EMULATED_RFI_EXITS,
d30f6e48 148 EMULATED_RFCI_EXITS,
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149 DEC_EXITS,
150 EXT_INTR_EXITS,
151 HALT_WAKEUP,
152 USR_PR_INST,
153 FP_UNAVAIL,
154 DEBUG_EXITS,
155 TIMEINGUEST,
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156 DBELL_EXITS,
157 GDBELL_EXITS,
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158 __NUMBER_OF_KVM_EXIT_TYPES
159};
160
73e75b41 161/* allow access to big endian 32bit upper/lower parts and 64bit var */
7b701591 162struct kvmppc_exit_timing {
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163 union {
164 u64 tv64;
165 struct {
166 u32 tbu, tbl;
167 } tv32;
168 };
169};
73e75b41 170
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171struct kvmppc_pginfo {
172 unsigned long pfn;
173 atomic_t refcnt;
174};
175
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176struct kvmppc_spapr_tce_table {
177 struct list_head list;
178 struct kvm *kvm;
179 u64 liobn;
180 u32 window_size;
181 struct page *pages[0];
182};
183
b4e70611 184struct kvmppc_linear_info {
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185 void *base_virt;
186 unsigned long base_pfn;
187 unsigned long npages;
188 struct list_head list;
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189 atomic_t use_count;
190 int type;
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191};
192
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193/*
194 * The reverse mapping array has one entry for each HPTE,
195 * which stores the guest's view of the second word of the HPTE
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196 * (including the guest physical address of the mapping),
197 * plus forward and backward pointers in a doubly-linked ring
198 * of HPTEs that map the same host page. The pointers in this
199 * ring are 32-bit HPTE indexes, to save space.
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200 */
201struct revmap_entry {
202 unsigned long guest_rpte;
06ce2c63 203 unsigned int forw, back;
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204};
205
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206/*
207 * We use the top bit of each memslot->rmap entry as a lock bit,
208 * and bit 32 as a present flag. The bottom 32 bits are the
209 * index in the guest HPT of a HPTE that points to the page.
210 */
211#define KVMPPC_RMAP_LOCK_BIT 63
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212#define KVMPPC_RMAP_RC_SHIFT 32
213#define KVMPPC_RMAP_REFERENCED (HPTE_R_R << KVMPPC_RMAP_RC_SHIFT)
214#define KVMPPC_RMAP_CHANGED (HPTE_R_C << KVMPPC_RMAP_RC_SHIFT)
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215#define KVMPPC_RMAP_PRESENT 0x100000000ul
216#define KVMPPC_RMAP_INDEX 0xfffffffful
217
b2b2f165 218/* Low-order bits in kvm->arch.slot_phys[][] */
da9d1d7f 219#define KVMPPC_PAGE_ORDER_MASK 0x1f
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220#define KVMPPC_PAGE_NO_CACHE HPTE_R_I /* 0x20 */
221#define KVMPPC_PAGE_WRITETHRU HPTE_R_W /* 0x40 */
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222#define KVMPPC_GOT_PAGE 0x80
223
db3fe4eb 224struct kvm_arch_memory_slot {
d89cc617 225 unsigned long *rmap;
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226};
227
bbf45ba5 228struct kvm_arch {
d30f6e48 229 unsigned int lpid;
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230#ifdef CONFIG_KVM_BOOK3S_64_HV
231 unsigned long hpt_virt;
8936dda4 232 struct revmap_entry *revmap;
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233 unsigned int host_lpid;
234 unsigned long host_lpcr;
235 unsigned long sdr1;
236 unsigned long host_sdr1;
237 int tlbie_lock;
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238 unsigned long lpcr;
239 unsigned long rmor;
b4e70611 240 struct kvmppc_linear_info *rma;
697d3899 241 unsigned long vrma_slb_v;
c77162de 242 int rma_setup_done;
342d3db7 243 int using_mmu_notifiers;
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244 u32 hpt_order;
245 atomic_t vcpus_running;
246 unsigned long hpt_npte;
247 unsigned long hpt_mask;
c77162de 248 spinlock_t slot_phys_lock;
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249 unsigned long *slot_phys[KVM_MEM_SLOTS_NUM];
250 int slot_npages[KVM_MEM_SLOTS_NUM];
de56a948 251 unsigned short last_vcpu[NR_CPUS];
371fefd6 252 struct kvmppc_vcore *vcores[KVM_MAX_VCORES];
d2a1b483 253 struct kvmppc_linear_info *hpt_li;
de56a948 254#endif /* CONFIG_KVM_BOOK3S_64_HV */
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255#ifdef CONFIG_PPC_BOOK3S_64
256 struct list_head spapr_tce_tables;
257#endif
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258};
259
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260/*
261 * Struct for a virtual core.
262 * Note: entry_exit_count combines an entry count in the bottom 8 bits
263 * and an exit count in the next 8 bits. This is so that we can
264 * atomically increment the entry count iff the exit count is 0
265 * without taking the lock.
266 */
267struct kvmppc_vcore {
268 int n_runnable;
19ccb76a 269 int n_busy;
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270 int num_threads;
271 int entry_exit_count;
272 int n_woken;
273 int nap_count;
19ccb76a 274 int napping_threads;
371fefd6 275 u16 pcpu;
19ccb76a 276 u8 vcore_state;
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277 u8 in_guest;
278 struct list_head runnable_threads;
279 spinlock_t lock;
19ccb76a 280 wait_queue_head_t wq;
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281 u64 stolen_tb;
282 u64 preempt_tb;
283 struct kvm_vcpu *runner;
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284};
285
286#define VCORE_ENTRY_COUNT(vc) ((vc)->entry_exit_count & 0xff)
287#define VCORE_EXIT_COUNT(vc) ((vc)->entry_exit_count >> 8)
288
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289/* Values for vcore_state */
290#define VCORE_INACTIVE 0
291#define VCORE_RUNNING 1
292#define VCORE_EXITING 2
293#define VCORE_SLEEPING 3
294
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295/*
296 * Struct used to manage memory for a virtual processor area
297 * registered by a PAPR guest. There are three types of area
298 * that a guest can register.
299 */
300struct kvmppc_vpa {
301 void *pinned_addr; /* Address in kernel linear mapping */
302 void *pinned_end; /* End of region */
303 unsigned long next_gpa; /* Guest phys addr for update */
304 unsigned long len; /* Number of bytes required */
305 u8 update_pending; /* 1 => update pinned_addr from next_gpa */
306};
307
ca95150b 308struct kvmppc_pte {
af7b4d10 309 ulong eaddr;
ca95150b 310 u64 vpage;
af7b4d10 311 ulong raddr;
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312 bool may_read : 1;
313 bool may_write : 1;
314 bool may_execute : 1;
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315};
316
317struct kvmppc_mmu {
318 /* book3s_64 only */
319 void (*slbmte)(struct kvm_vcpu *vcpu, u64 rb, u64 rs);
320 u64 (*slbmfee)(struct kvm_vcpu *vcpu, u64 slb_nr);
321 u64 (*slbmfev)(struct kvm_vcpu *vcpu, u64 slb_nr);
322 void (*slbie)(struct kvm_vcpu *vcpu, u64 slb_nr);
323 void (*slbia)(struct kvm_vcpu *vcpu);
324 /* book3s */
325 void (*mtsrin)(struct kvm_vcpu *vcpu, u32 srnum, ulong value);
326 u32 (*mfsrin)(struct kvm_vcpu *vcpu, u32 srnum);
327 int (*xlate)(struct kvm_vcpu *vcpu, gva_t eaddr, struct kvmppc_pte *pte, bool data);
328 void (*reset_msr)(struct kvm_vcpu *vcpu);
329 void (*tlbie)(struct kvm_vcpu *vcpu, ulong addr, bool large);
af7b4d10 330 int (*esid_to_vsid)(struct kvm_vcpu *vcpu, ulong esid, u64 *vsid);
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331 u64 (*ea_to_vp)(struct kvm_vcpu *vcpu, gva_t eaddr, bool data);
332 bool (*is_dcbz32)(struct kvm_vcpu *vcpu);
333};
334
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335struct kvmppc_slb {
336 u64 esid;
337 u64 vsid;
338 u64 orige;
339 u64 origv;
340 bool valid : 1;
341 bool Ks : 1;
342 bool Kp : 1;
343 bool nx : 1;
344 bool large : 1; /* PTEs are 16MB */
345 bool tb : 1; /* 1TB segment */
346 bool class : 1;
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347};
348
bbf45ba5 349struct kvm_vcpu_arch {
ca95150b 350 ulong host_stack;
bbf45ba5 351 u32 host_pid;
00c3a37c 352#ifdef CONFIG_PPC_BOOK3S
c4befc58 353 struct kvmppc_slb slb[64];
de56a948 354 int slb_max; /* 1 + index of last valid entry in slb[] */
c4befc58 355 int slb_nr; /* total number of entries in SLB */
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356 struct kvmppc_mmu mmu;
357#endif
bbf45ba5 358
5cf8ca22 359 ulong gpr[32];
bbf45ba5 360
180a34d2 361 u64 fpr[32];
c62e096d 362 u64 fpscr;
180a34d2 363
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364#ifdef CONFIG_SPE
365 ulong evr[32];
366 ulong spefscr;
367 ulong host_spefscr;
368 u64 acc;
369#endif
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370#ifdef CONFIG_ALTIVEC
371 vector128 vr[32];
372 vector128 vscr;
373#endif
374
375#ifdef CONFIG_VSX
de56a948 376 u64 vsr[64];
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377#endif
378
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379#ifdef CONFIG_KVM_BOOKE_HV
380 u32 host_mas4;
381 u32 host_mas6;
382 u32 shadow_epcr;
383 u32 epcr;
384 u32 shadow_msrp;
385 u32 eplc;
386 u32 epsc;
387 u32 oldpir;
388#endif
389
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390#ifdef CONFIG_PPC_BOOK3S
391 /* For Gekko paired singles */
392 u32 qpr[32];
393#endif
394
5cf8ca22 395 ulong pc;
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396 ulong ctr;
397 ulong lr;
7e57cba0 398
5cf8ca22 399 ulong xer;
7e57cba0 400 u32 cr;
bbf45ba5 401
00c3a37c 402#ifdef CONFIG_PPC_BOOK3S
ca95150b 403 ulong hflags;
180a34d2 404 ulong guest_owned_ext;
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405 ulong purr;
406 ulong spurr;
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407 ulong dscr;
408 ulong amr;
409 ulong uamor;
410 u32 ctrl;
411 ulong dabr;
ca95150b 412#endif
eab17672 413 u32 vrsave; /* also USPRG0 */
bbf45ba5 414 u32 mmucr;
5fd8505e 415 /* shadow_msr is unused for BookE HV */
ecee273f 416 ulong shadow_msr;
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417 ulong csrr0;
418 ulong csrr1;
419 ulong dsrr0;
420 ulong dsrr1;
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421 ulong mcsrr0;
422 ulong mcsrr1;
423 ulong mcsr;
bbf45ba5 424 u32 dec;
21bd000a 425#ifdef CONFIG_BOOKE
bbf45ba5 426 u32 decar;
21bd000a 427#endif
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428 u32 tbl;
429 u32 tbu;
430 u32 tcr;
dfd4d47e 431 ulong tsr; /* we need to perform set/clr_bits() which requires ulong */
bb3a8a17 432 u32 ivor[64];
5cf8ca22 433 ulong ivpr;
ca95150b 434 u32 pvr;
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435
436 u32 shadow_pid;
dd9ebf1f 437 u32 shadow_pid1;
bbf45ba5 438 u32 pid;
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439 u32 swap_pid;
440
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441 u32 ccr0;
442 u32 ccr1;
443 u32 dbcr0;
444 u32 dbcr1;
f7b200af 445 u32 dbsr;
bbf45ba5 446
de56a948 447 u64 mmcr[3];
9e368f29 448 u32 pmc[8];
de56a948 449
73e75b41 450#ifdef CONFIG_KVM_EXIT_TIMING
09000adb 451 struct mutex exit_timing_lock;
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452 struct kvmppc_exit_timing timing_exit;
453 struct kvmppc_exit_timing timing_last_enter;
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454 u32 last_exit_type;
455 u32 timing_count_type[__NUMBER_OF_KVM_EXIT_TYPES];
456 u64 timing_sum_duration[__NUMBER_OF_KVM_EXIT_TYPES];
457 u64 timing_sum_quad_duration[__NUMBER_OF_KVM_EXIT_TYPES];
458 u64 timing_min_duration[__NUMBER_OF_KVM_EXIT_TYPES];
459 u64 timing_max_duration[__NUMBER_OF_KVM_EXIT_TYPES];
460 u64 timing_last_exit;
461 struct dentry *debugfs_exit_timing;
462#endif
463
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464#ifdef CONFIG_PPC_BOOK3S
465 ulong fault_dar;
466 u32 fault_dsisr;
467#endif
468
0604675f 469#ifdef CONFIG_BOOKE
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470 ulong fault_dear;
471 ulong fault_esr;
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472 ulong queued_dear;
473 ulong queued_esr;
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474 u32 tlbcfg[4];
475 u32 mmucfg;
d30f6e48 476 u32 epr;
0604675f 477#endif
bbf45ba5 478 gpa_t paddr_accessed;
6020c0f6 479 gva_t vaddr_accessed;
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480
481 u8 io_gpr; /* GPR used as IO source/target */
482 u8 mmio_is_bigendian;
3587d534 483 u8 mmio_sign_extend;
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484 u8 dcr_needed;
485 u8 dcr_is_write;
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486 u8 osi_needed;
487 u8 osi_enabled;
9432ba60 488 u8 papr_enabled;
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489 u8 sane;
490 u8 cpu_type;
de56a948 491 u8 hcall_needed;
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492
493 u32 cpr0_cfgaddr; /* holds the last set cpr0_cfgaddr */
494
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495 struct hrtimer dec_timer;
496 struct tasklet_struct tasklet;
ca95150b 497 u64 dec_jiffies;
de56a948 498 u64 dec_expires;
bbf45ba5 499 unsigned long pending_exceptions;
de56a948 500 u16 last_cpu;
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501 u8 ceded;
502 u8 prodded;
de56a948 503 u32 last_inst;
a8606e20 504
19ccb76a 505 wait_queue_head_t *wqp;
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506 struct kvmppc_vcore *vcore;
507 int ret;
de56a948 508 int trap;
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509 int state;
510 int ptid;
19ccb76a 511 bool timer_running;
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512 wait_queue_head_t cpu_run;
513
96bc451a 514 struct kvm_vcpu_arch_shared *shared;
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515 unsigned long magic_page_pa; /* phys addr to map the magic page to */
516 unsigned long magic_page_ea; /* effect. addr to map the magic page to */
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517
518#ifdef CONFIG_KVM_BOOK3S_64_HV
519 struct kvm_vcpu_arch_shared shregs;
371fefd6 520
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521 unsigned long pgfault_addr;
522 long pgfault_index;
523 unsigned long pgfault_hpte[2];
524
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525 struct list_head run_list;
526 struct task_struct *run_task;
527 struct kvm_run *kvm_run;
342d3db7 528 pgd_t *pgdir;
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529
530 spinlock_t vpa_update_lock;
531 struct kvmppc_vpa vpa;
532 struct kvmppc_vpa dtl;
533 struct dtl_entry *dtl_ptr;
534 unsigned long dtl_index;
0456ec4f 535 u64 stolen_logged;
2e25aa5f 536 struct kvmppc_vpa slb_shadow;
de56a948 537#endif
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538};
539
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540/* Values for vcpu->arch.state */
541#define KVMPPC_VCPU_STOPPED 0
542#define KVMPPC_VCPU_BUSY_IN_HOST 1
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543#define KVMPPC_VCPU_RUNNABLE 2
544
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545/* Values for vcpu->arch.io_gpr */
546#define KVM_MMIO_REG_MASK 0x001f
547#define KVM_MMIO_REG_EXT_MASK 0xffe0
548#define KVM_MMIO_REG_GPR 0x0000
549#define KVM_MMIO_REG_FPR 0x0020
550#define KVM_MMIO_REG_QPR 0x0040
551#define KVM_MMIO_REG_FQPR 0x0060
552
2246f8b5 553#define __KVM_HAVE_ARCH_WQP
b6d33834 554
bbf45ba5 555#endif /* __POWERPC_KVM_HOST_H__ */
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