root/arch/powerpc/include/asm/kvm_book3s.h

INCLUDED FROM

DEFINITIONS

1. kvmppc_save_tm_pr
2. kvmppc_restore_tm_pr
3. kvmppc_save_tm_sprs
4. kvmppc_restore_tm_sprs
5. to_book3s
6. kvmppc_set_gpr
7. kvmppc_get_gpr
8. kvmppc_set_cr
9. kvmppc_get_cr
10. kvmppc_set_xer
11. kvmppc_get_xer
12. kvmppc_set_ctr
13. kvmppc_get_ctr
14. kvmppc_set_lr
15. kvmppc_get_lr
16. kvmppc_set_pc
17. kvmppc_get_pc
18. kvmppc_need_byteswap
19. kvmppc_get_fault_dar
20. is_kvmppc_resume_guest
21. kvmppc_supports_magic_page
22. kvmppc_pack_vcpu_id

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  *
   4  * Copyright SUSE Linux Products GmbH 2009
   5  *
   6  * Authors: Alexander Graf <agraf@suse.de>
   7  */
   8 
   9 #ifndef __ASM_KVM_BOOK3S_H__
  10 #define __ASM_KVM_BOOK3S_H__
  11 
  12 #include <linux/types.h>
  13 #include <linux/kvm_host.h>
  14 #include <asm/kvm_book3s_asm.h>
  15 
  16 struct kvmppc_bat {
  17         u64 raw;
  18         u32 bepi;
  19         u32 bepi_mask;
  20         u32 brpn;
  21         u8 wimg;
  22         u8 pp;
  23         bool vs         : 1;
  24         bool vp         : 1;
  25 };
  26 
  27 struct kvmppc_sid_map {
  28         u64 guest_vsid;
  29         u64 guest_esid;
  30         u64 host_vsid;
  31         bool valid      : 1;
  32 };
  33 
  34 #define SID_MAP_BITS    9
  35 #define SID_MAP_NUM     (1 << SID_MAP_BITS)
  36 #define SID_MAP_MASK    (SID_MAP_NUM - 1)
  37 
  38 #ifdef CONFIG_PPC_BOOK3S_64
  39 #define SID_CONTEXTS    1
  40 #else
  41 #define SID_CONTEXTS    128
  42 #define VSID_POOL_SIZE  (SID_CONTEXTS * 16)
  43 #endif
  44 
  45 struct hpte_cache {
  46         struct hlist_node list_pte;
  47         struct hlist_node list_pte_long;
  48         struct hlist_node list_vpte;
  49         struct hlist_node list_vpte_long;
  50 #ifdef CONFIG_PPC_BOOK3S_64
  51         struct hlist_node list_vpte_64k;
  52 #endif
  53         struct rcu_head rcu_head;
  54         u64 host_vpn;
  55         u64 pfn;
  56         ulong slot;
  57         struct kvmppc_pte pte;
  58         int pagesize;
  59 };
  60 
  61 /*
  62  * Struct for a virtual core.
  63  * Note: entry_exit_map combines a bitmap of threads that have entered
  64  * in the bottom 8 bits and a bitmap of threads that have exited in the
  65  * next 8 bits.  This is so that we can atomically set the entry bit
  66  * iff the exit map is 0 without taking a lock.
  67  */
  68 struct kvmppc_vcore {
  69         int n_runnable;
  70         int num_threads;
  71         int entry_exit_map;
  72         int napping_threads;
  73         int first_vcpuid;
  74         u16 pcpu;
  75         u16 last_cpu;
  76         u8 vcore_state;
  77         u8 in_guest;
  78         struct kvm_vcpu *runnable_threads[MAX_SMT_THREADS];
  79         struct list_head preempt_list;
  80         spinlock_t lock;
  81         struct swait_queue_head wq;
  82         spinlock_t stoltb_lock; /* protects stolen_tb and preempt_tb */
  83         u64 stolen_tb;
  84         u64 preempt_tb;
  85         struct kvm_vcpu *runner;
  86         struct kvm *kvm;
  87         u64 tb_offset;          /* guest timebase - host timebase */
  88         u64 tb_offset_applied;  /* timebase offset currently in force */
  89         ulong lpcr;
  90         u32 arch_compat;
  91         ulong pcr;
  92         ulong dpdes;            /* doorbell state (POWER8) */
  93         ulong vtb;              /* virtual timebase */
  94         ulong conferring_threads;
  95         unsigned int halt_poll_ns;
  96         atomic_t online_count;
  97 };
  98 
  99 struct kvmppc_vcpu_book3s {
 100         struct kvmppc_sid_map sid_map[SID_MAP_NUM];
 101         struct {
 102                 u64 esid;
 103                 u64 vsid;
 104         } slb_shadow[64];
 105         u8 slb_shadow_max;
 106         struct kvmppc_bat ibat[8];
 107         struct kvmppc_bat dbat[8];
 108         u64 hid[6];
 109         u64 gqr[8];
 110         u64 sdr1;
 111         u64 hior;
 112         u64 msr_mask;
 113         u64 vtb;
 114 #ifdef CONFIG_PPC_BOOK3S_32
 115         u32 vsid_pool[VSID_POOL_SIZE];
 116         u32 vsid_next;
 117 #else
 118         u64 proto_vsid_first;
 119         u64 proto_vsid_max;
 120         u64 proto_vsid_next;
 121 #endif
 122         int context_id[SID_CONTEXTS];
 123 
 124         bool hior_explicit;             /* HIOR is set by ioctl, not PVR */
 125 
 126         struct hlist_head hpte_hash_pte[HPTEG_HASH_NUM_PTE];
 127         struct hlist_head hpte_hash_pte_long[HPTEG_HASH_NUM_PTE_LONG];
 128         struct hlist_head hpte_hash_vpte[HPTEG_HASH_NUM_VPTE];
 129         struct hlist_head hpte_hash_vpte_long[HPTEG_HASH_NUM_VPTE_LONG];
 130 #ifdef CONFIG_PPC_BOOK3S_64
 131         struct hlist_head hpte_hash_vpte_64k[HPTEG_HASH_NUM_VPTE_64K];
 132 #endif
 133         int hpte_cache_count;
 134         spinlock_t mmu_lock;
 135 };
 136 
 137 #define VSID_REAL       0x07ffffffffc00000ULL
 138 #define VSID_BAT        0x07ffffffffb00000ULL
 139 #define VSID_64K        0x0800000000000000ULL
 140 #define VSID_1T         0x1000000000000000ULL
 141 #define VSID_REAL_DR    0x2000000000000000ULL
 142 #define VSID_REAL_IR    0x4000000000000000ULL
 143 #define VSID_PR         0x8000000000000000ULL
 144 
 145 extern void kvmppc_mmu_pte_flush(struct kvm_vcpu *vcpu, ulong ea, ulong ea_mask);
 146 extern void kvmppc_mmu_pte_vflush(struct kvm_vcpu *vcpu, u64 vp, u64 vp_mask);
 147 extern void kvmppc_mmu_pte_pflush(struct kvm_vcpu *vcpu, ulong pa_start, ulong pa_end);
 148 extern void kvmppc_set_msr(struct kvm_vcpu *vcpu, u64 new_msr);
 149 extern void kvmppc_mmu_book3s_64_init(struct kvm_vcpu *vcpu);
 150 extern void kvmppc_mmu_book3s_32_init(struct kvm_vcpu *vcpu);
 151 extern void kvmppc_mmu_book3s_hv_init(struct kvm_vcpu *vcpu);
 152 extern int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *pte,
 153                                bool iswrite);
 154 extern void kvmppc_mmu_unmap_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *pte);
 155 extern int kvmppc_mmu_map_segment(struct kvm_vcpu *vcpu, ulong eaddr);
 156 extern void kvmppc_mmu_flush_segment(struct kvm_vcpu *vcpu, ulong eaddr, ulong seg_size);
 157 extern void kvmppc_mmu_flush_segments(struct kvm_vcpu *vcpu);
 158 extern int kvmppc_book3s_hv_page_fault(struct kvm_run *run,
 159                         struct kvm_vcpu *vcpu, unsigned long addr,
 160                         unsigned long status);
 161 extern long kvmppc_hv_find_lock_hpte(struct kvm *kvm, gva_t eaddr,
 162                         unsigned long slb_v, unsigned long valid);
 163 extern int kvmppc_hv_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu,
 164                         unsigned long gpa, gva_t ea, int is_store);
 165 
 166 extern void kvmppc_mmu_hpte_cache_map(struct kvm_vcpu *vcpu, struct hpte_cache *pte);
 167 extern struct hpte_cache *kvmppc_mmu_hpte_cache_next(struct kvm_vcpu *vcpu);
 168 extern void kvmppc_mmu_hpte_cache_free(struct hpte_cache *pte);
 169 extern void kvmppc_mmu_hpte_destroy(struct kvm_vcpu *vcpu);
 170 extern int kvmppc_mmu_hpte_init(struct kvm_vcpu *vcpu);
 171 extern void kvmppc_mmu_invalidate_pte(struct kvm_vcpu *vcpu, struct hpte_cache *pte);
 172 extern int kvmppc_mmu_hpte_sysinit(void);
 173 extern void kvmppc_mmu_hpte_sysexit(void);
 174 extern int kvmppc_mmu_hv_init(void);
 175 extern int kvmppc_book3s_hcall_implemented(struct kvm *kvm, unsigned long hc);
 176 
 177 extern int kvmppc_book3s_radix_page_fault(struct kvm_run *run,
 178                         struct kvm_vcpu *vcpu,
 179                         unsigned long ea, unsigned long dsisr);
 180 extern unsigned long __kvmhv_copy_tofrom_guest_radix(int lpid, int pid,
 181                                         gva_t eaddr, void *to, void *from,
 182                                         unsigned long n);
 183 extern long kvmhv_copy_from_guest_radix(struct kvm_vcpu *vcpu, gva_t eaddr,
 184                                         void *to, unsigned long n);
 185 extern long kvmhv_copy_to_guest_radix(struct kvm_vcpu *vcpu, gva_t eaddr,
 186                                       void *from, unsigned long n);
 187 extern int kvmppc_mmu_walk_radix_tree(struct kvm_vcpu *vcpu, gva_t eaddr,
 188                                       struct kvmppc_pte *gpte, u64 root,
 189                                       u64 *pte_ret_p);
 190 extern int kvmppc_mmu_radix_translate_table(struct kvm_vcpu *vcpu, gva_t eaddr,
 191                         struct kvmppc_pte *gpte, u64 table,
 192                         int table_index, u64 *pte_ret_p);
 193 extern int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
 194                         struct kvmppc_pte *gpte, bool data, bool iswrite);
 195 extern void kvmppc_radix_tlbie_page(struct kvm *kvm, unsigned long addr,
 196                                     unsigned int pshift, unsigned int lpid);
 197 extern void kvmppc_unmap_pte(struct kvm *kvm, pte_t *pte, unsigned long gpa,
 198                         unsigned int shift,
 199                         const struct kvm_memory_slot *memslot,
 200                         unsigned int lpid);
 201 extern bool kvmppc_hv_handle_set_rc(struct kvm *kvm, pgd_t *pgtable,
 202                                     bool writing, unsigned long gpa,
 203                                     unsigned int lpid);
 204 extern int kvmppc_book3s_instantiate_page(struct kvm_vcpu *vcpu,
 205                                 unsigned long gpa,
 206                                 struct kvm_memory_slot *memslot,
 207                                 bool writing, bool kvm_ro,
 208                                 pte_t *inserted_pte, unsigned int *levelp);
 209 extern int kvmppc_init_vm_radix(struct kvm *kvm);
 210 extern void kvmppc_free_radix(struct kvm *kvm);
 211 extern void kvmppc_free_pgtable_radix(struct kvm *kvm, pgd_t *pgd,
 212                                       unsigned int lpid);
 213 extern int kvmppc_radix_init(void);
 214 extern void kvmppc_radix_exit(void);
 215 extern int kvm_unmap_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
 216                         unsigned long gfn);
 217 extern int kvm_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
 218                         unsigned long gfn);
 219 extern int kvm_test_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
 220                         unsigned long gfn);
 221 extern long kvmppc_hv_get_dirty_log_radix(struct kvm *kvm,
 222                         struct kvm_memory_slot *memslot, unsigned long *map);
 223 extern void kvmppc_radix_flush_memslot(struct kvm *kvm,
 224                         const struct kvm_memory_slot *memslot);
 225 extern int kvmhv_get_rmmu_info(struct kvm *kvm, struct kvm_ppc_rmmu_info *info);
 226 
 227 /* XXX remove this export when load_last_inst() is generic */
 228 extern int kvmppc_ld(struct kvm_vcpu *vcpu, ulong *eaddr, int size, void *ptr, bool data);
 229 extern void kvmppc_book3s_queue_irqprio(struct kvm_vcpu *vcpu, unsigned int vec);
 230 extern void kvmppc_book3s_dequeue_irqprio(struct kvm_vcpu *vcpu,
 231                                           unsigned int vec);
 232 extern void kvmppc_inject_interrupt(struct kvm_vcpu *vcpu, int vec, u64 flags);
 233 extern void kvmppc_trigger_fac_interrupt(struct kvm_vcpu *vcpu, ulong fac);
 234 extern void kvmppc_set_bat(struct kvm_vcpu *vcpu, struct kvmppc_bat *bat,
 235                            bool upper, u32 val);
 236 extern void kvmppc_giveup_ext(struct kvm_vcpu *vcpu, ulong msr);
 237 extern int kvmppc_emulate_paired_single(struct kvm_run *run, struct kvm_vcpu *vcpu);
 238 extern kvm_pfn_t kvmppc_gpa_to_pfn(struct kvm_vcpu *vcpu, gpa_t gpa,
 239                         bool writing, bool *writable);
 240 extern void kvmppc_add_revmap_chain(struct kvm *kvm, struct revmap_entry *rev,
 241                         unsigned long *rmap, long pte_index, int realmode);
 242 extern void kvmppc_update_dirty_map(const struct kvm_memory_slot *memslot,
 243                         unsigned long gfn, unsigned long psize);
 244 extern void kvmppc_invalidate_hpte(struct kvm *kvm, __be64 *hptep,
 245                         unsigned long pte_index);
 246 void kvmppc_clear_ref_hpte(struct kvm *kvm, __be64 *hptep,
 247                         unsigned long pte_index);
 248 extern void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long addr,
 249                         unsigned long *nb_ret);
 250 extern void kvmppc_unpin_guest_page(struct kvm *kvm, void *addr,
 251                         unsigned long gpa, bool dirty);
 252 extern long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags,
 253                         long pte_index, unsigned long pteh, unsigned long ptel,
 254                         pgd_t *pgdir, bool realmode, unsigned long *idx_ret);
 255 extern long kvmppc_do_h_remove(struct kvm *kvm, unsigned long flags,
 256                         unsigned long pte_index, unsigned long avpn,
 257                         unsigned long *hpret);
 258 extern long kvmppc_hv_get_dirty_log_hpt(struct kvm *kvm,
 259                         struct kvm_memory_slot *memslot, unsigned long *map);
 260 extern void kvmppc_harvest_vpa_dirty(struct kvmppc_vpa *vpa,
 261                         struct kvm_memory_slot *memslot,
 262                         unsigned long *map);
 263 extern void kvmppc_update_lpcr(struct kvm *kvm, unsigned long lpcr,
 264                         unsigned long mask);
 265 extern void kvmppc_set_fscr(struct kvm_vcpu *vcpu, u64 fscr);
 266 
 267 extern int kvmhv_p9_tm_emulation_early(struct kvm_vcpu *vcpu);
 268 extern int kvmhv_p9_tm_emulation(struct kvm_vcpu *vcpu);
 269 extern void kvmhv_emulate_tm_rollback(struct kvm_vcpu *vcpu);
 270 
 271 extern void kvmppc_entry_trampoline(void);
 272 extern void kvmppc_hv_entry_trampoline(void);
 273 extern u32 kvmppc_alignment_dsisr(struct kvm_vcpu *vcpu, unsigned int inst);
 274 extern ulong kvmppc_alignment_dar(struct kvm_vcpu *vcpu, unsigned int inst);
 275 extern int kvmppc_h_pr(struct kvm_vcpu *vcpu, unsigned long cmd);
 276 extern void kvmppc_pr_init_default_hcalls(struct kvm *kvm);
 277 extern int kvmppc_hcall_impl_pr(unsigned long cmd);
 278 extern int kvmppc_hcall_impl_hv_realmode(unsigned long cmd);
 279 extern void kvmppc_copy_to_svcpu(struct kvm_vcpu *vcpu);
 280 extern void kvmppc_copy_from_svcpu(struct kvm_vcpu *vcpu);
 281 
 282 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 283 void kvmppc_save_tm_pr(struct kvm_vcpu *vcpu);
 284 void kvmppc_restore_tm_pr(struct kvm_vcpu *vcpu);
 285 void kvmppc_save_tm_sprs(struct kvm_vcpu *vcpu);
 286 void kvmppc_restore_tm_sprs(struct kvm_vcpu *vcpu);
 287 #else
 288 static inline void kvmppc_save_tm_pr(struct kvm_vcpu *vcpu) {}
 289 static inline void kvmppc_restore_tm_pr(struct kvm_vcpu *vcpu) {}
 290 static inline void kvmppc_save_tm_sprs(struct kvm_vcpu *vcpu) {}
 291 static inline void kvmppc_restore_tm_sprs(struct kvm_vcpu *vcpu) {}
 292 #endif
 293 
 294 long kvmhv_nested_init(void);
 295 void kvmhv_nested_exit(void);
 296 void kvmhv_vm_nested_init(struct kvm *kvm);
 297 long kvmhv_set_partition_table(struct kvm_vcpu *vcpu);
 298 long kvmhv_copy_tofrom_guest_nested(struct kvm_vcpu *vcpu);
 299 void kvmhv_set_ptbl_entry(unsigned int lpid, u64 dw0, u64 dw1);
 300 void kvmhv_release_all_nested(struct kvm *kvm);
 301 long kvmhv_enter_nested_guest(struct kvm_vcpu *vcpu);
 302 long kvmhv_do_nested_tlbie(struct kvm_vcpu *vcpu);
 303 int kvmhv_run_single_vcpu(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu,
 304                           u64 time_limit, unsigned long lpcr);
 305 void kvmhv_save_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr);
 306 void kvmhv_restore_hv_return_state(struct kvm_vcpu *vcpu,
 307                                    struct hv_guest_state *hr);
 308 long int kvmhv_nested_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu);
 309 
 310 void kvmppc_giveup_fac(struct kvm_vcpu *vcpu, ulong fac);
 311 
 312 extern int kvm_irq_bypass;
 313 
 314 static inline struct kvmppc_vcpu_book3s *to_book3s(struct kvm_vcpu *vcpu)
 315 {
 316         return vcpu->arch.book3s;
 317 }
 318 
 319 /* Also add subarch specific defines */
 320 
 321 #ifdef CONFIG_KVM_BOOK3S_32_HANDLER
 322 #include <asm/kvm_book3s_32.h>
 323 #endif
 324 #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
 325 #include <asm/kvm_book3s_64.h>
 326 #endif
 327 
 328 static inline void kvmppc_set_gpr(struct kvm_vcpu *vcpu, int num, ulong val)
 329 {
 330         vcpu->arch.regs.gpr[num] = val;
 331 }
 332 
 333 static inline ulong kvmppc_get_gpr(struct kvm_vcpu *vcpu, int num)
 334 {
 335         return vcpu->arch.regs.gpr[num];
 336 }
 337 
 338 static inline void kvmppc_set_cr(struct kvm_vcpu *vcpu, u32 val)
 339 {
 340         vcpu->arch.regs.ccr = val;
 341 }
 342 
 343 static inline u32 kvmppc_get_cr(struct kvm_vcpu *vcpu)
 344 {
 345         return vcpu->arch.regs.ccr;
 346 }
 347 
 348 static inline void kvmppc_set_xer(struct kvm_vcpu *vcpu, ulong val)
 349 {
 350         vcpu->arch.regs.xer = val;
 351 }
 352 
 353 static inline ulong kvmppc_get_xer(struct kvm_vcpu *vcpu)
 354 {
 355         return vcpu->arch.regs.xer;
 356 }
 357 
 358 static inline void kvmppc_set_ctr(struct kvm_vcpu *vcpu, ulong val)
 359 {
 360         vcpu->arch.regs.ctr = val;
 361 }
 362 
 363 static inline ulong kvmppc_get_ctr(struct kvm_vcpu *vcpu)
 364 {
 365         return vcpu->arch.regs.ctr;
 366 }
 367 
 368 static inline void kvmppc_set_lr(struct kvm_vcpu *vcpu, ulong val)
 369 {
 370         vcpu->arch.regs.link = val;
 371 }
 372 
 373 static inline ulong kvmppc_get_lr(struct kvm_vcpu *vcpu)
 374 {
 375         return vcpu->arch.regs.link;
 376 }
 377 
 378 static inline void kvmppc_set_pc(struct kvm_vcpu *vcpu, ulong val)
 379 {
 380         vcpu->arch.regs.nip = val;
 381 }
 382 
 383 static inline ulong kvmppc_get_pc(struct kvm_vcpu *vcpu)
 384 {
 385         return vcpu->arch.regs.nip;
 386 }
 387 
 388 static inline u64 kvmppc_get_msr(struct kvm_vcpu *vcpu);
 389 static inline bool kvmppc_need_byteswap(struct kvm_vcpu *vcpu)
 390 {
 391         return (kvmppc_get_msr(vcpu) & MSR_LE) != (MSR_KERNEL & MSR_LE);
 392 }
 393 
 394 static inline ulong kvmppc_get_fault_dar(struct kvm_vcpu *vcpu)
 395 {
 396         return vcpu->arch.fault_dar;
 397 }
 398 
 399 static inline bool is_kvmppc_resume_guest(int r)
 400 {
 401         return (r == RESUME_GUEST || r == RESUME_GUEST_NV);
 402 }
 403 
 404 static inline bool is_kvmppc_hv_enabled(struct kvm *kvm);
 405 static inline bool kvmppc_supports_magic_page(struct kvm_vcpu *vcpu)
 406 {
 407         /* Only PR KVM supports the magic page */
 408         return !is_kvmppc_hv_enabled(vcpu->kvm);
 409 }
 410 
 411 extern int kvmppc_h_logical_ci_load(struct kvm_vcpu *vcpu);
 412 extern int kvmppc_h_logical_ci_store(struct kvm_vcpu *vcpu);
 413 
 414 /* Magic register values loaded into r3 and r4 before the 'sc' assembly
 415  * instruction for the OSI hypercalls */
 416 #define OSI_SC_MAGIC_R3                 0x113724FA
 417 #define OSI_SC_MAGIC_R4                 0x77810F9B
 418 
 419 #define INS_DCBZ                        0x7c0007ec
 420 /* TO = 31 for unconditional trap */
 421 #define INS_TW                          0x7fe00008
 422 
 423 #define SPLIT_HACK_MASK                 0xff000000
 424 #define SPLIT_HACK_OFFS                 0xfb000000
 425 
 426 /*
 427  * This packs a VCPU ID from the [0..KVM_MAX_VCPU_ID) space down to the
 428  * [0..KVM_MAX_VCPUS) space, using knowledge of the guest's core stride
 429  * (but not its actual threading mode, which is not available) to avoid
 430  * collisions.
 431  *
 432  * The implementation leaves VCPU IDs from the range [0..KVM_MAX_VCPUS) (block
 433  * 0) unchanged: if the guest is filling each VCORE completely then it will be
 434  * using consecutive IDs and it will fill the space without any packing.
 435  *
 436  * For higher VCPU IDs, the packed ID is based on the VCPU ID modulo
 437  * KVM_MAX_VCPUS (effectively masking off the top bits) and then an offset is
 438  * added to avoid collisions.
 439  *
 440  * VCPU IDs in the range [KVM_MAX_VCPUS..(KVM_MAX_VCPUS*2)) (block 1) are only
 441  * possible if the guest is leaving at least 1/2 of each VCORE empty, so IDs
 442  * can be safely packed into the second half of each VCORE by adding an offset
 443  * of (stride / 2).
 444  *
 445  * Similarly, if VCPU IDs in the range [(KVM_MAX_VCPUS*2)..(KVM_MAX_VCPUS*4))
 446  * (blocks 2 and 3) are seen, the guest must be leaving at least 3/4 of each
 447  * VCORE empty so packed IDs can be offset by (stride / 4) and (stride * 3 / 4).
 448  *
 449  * Finally, VCPU IDs from blocks 5..7 will only be seen if the guest is using a
 450  * stride of 8 and 1 thread per core so the remaining offsets of 1, 5, 3 and 7
 451  * must be free to use.
 452  *
 453  * (The offsets for each block are stored in block_offsets[], indexed by the
 454  * block number if the stride is 8. For cases where the guest's stride is less
 455  * than 8, we can re-use the block_offsets array by multiplying the block
 456  * number by (MAX_SMT_THREADS / stride) to reach the correct entry.)
 457  */
 458 static inline u32 kvmppc_pack_vcpu_id(struct kvm *kvm, u32 id)
 459 {
 460         const int block_offsets[MAX_SMT_THREADS] = {0, 4, 2, 6, 1, 5, 3, 7};
 461         int stride = kvm->arch.emul_smt_mode;
 462         int block = (id / KVM_MAX_VCPUS) * (MAX_SMT_THREADS / stride);
 463         u32 packed_id;
 464 
 465         if (WARN_ONCE(block >= MAX_SMT_THREADS, "VCPU ID too large to pack"))
 466                 return 0;
 467         packed_id = (id % KVM_MAX_VCPUS) + block_offsets[block];
 468         if (WARN_ONCE(packed_id >= KVM_MAX_VCPUS, "VCPU ID packing failed"))
 469                 return 0;
 470         return packed_id;
 471 }
 472 
 473 #endif /* __ASM_KVM_BOOK3S_H__ */