include/asm/kvm_book3s.h

0001 /* SPDX-License-Identifier: GPL-2.0-only */
0002 /*
0003  *
0004  * Copyright SUSE Linux Products GmbH 2009
0005  *
0006  * Authors: Alexander Graf <agraf@suse.de>
0007  */
0008
0009 #ifndef __ASM_KVM_BOOK3S_H__
0010 #define __ASM_KVM_BOOK3S_H__
0011
0012 #include <linux/types.h>
0013 #include <linux/kvm_host.h>
0014 #include <asm/kvm_book3s_asm.h>
0015
0016 struct kvmppc_bat {
0017     u64 raw;
0018     u32 bepi;
0019     u32 bepi_mask;
0020     u32 brpn;
0021     u8 wimg;
0022     u8 pp;
0023     bool vs     : 1;
0024     bool vp     : 1;
0025 };
0026
0027 struct kvmppc_sid_map {
0028     u64 guest_vsid;
0029     u64 guest_esid;
0030     u64 host_vsid;
0031     bool valid  : 1;
0032 };
0033
0034 #define SID_MAP_BITS    9
0035 #define SID_MAP_NUM     (1 << SID_MAP_BITS)
0036 #define SID_MAP_MASK    (SID_MAP_NUM - 1)
0037
0038 #ifdef CONFIG_PPC_BOOK3S_64
0039 #define SID_CONTEXTS    1
0040 #else
0041 #define SID_CONTEXTS    128
0042 #define VSID_POOL_SIZE  (SID_CONTEXTS * 16)
0043 #endif
0044
0045 struct hpte_cache {
0046     struct hlist_node list_pte;
0047     struct hlist_node list_pte_long;
0048     struct hlist_node list_vpte;
0049     struct hlist_node list_vpte_long;
0050 #ifdef CONFIG_PPC_BOOK3S_64
0051     struct hlist_node list_vpte_64k;
0052 #endif
0053     struct rcu_head rcu_head;
0054     u64 host_vpn;
0055     u64 pfn;
0056     ulong slot;
0057     struct kvmppc_pte pte;
0058     int pagesize;
0059 };
0060
0061 /*
0062  * Struct for a virtual core.
0063  * Note: entry_exit_map combines a bitmap of threads that have entered
0064  * in the bottom 8 bits and a bitmap of threads that have exited in the
0065  * next 8 bits.  This is so that we can atomically set the entry bit
0066  * iff the exit map is 0 without taking a lock.
0067  */
0068 struct kvmppc_vcore {
0069     int n_runnable;
0070     int num_threads;
0071     int entry_exit_map;
0072     int napping_threads;
0073     int first_vcpuid;
0074     u16 pcpu;
0075     u16 last_cpu;
0076     u8 vcore_state;
0077     u8 in_guest;
0078     struct kvm_vcpu *runnable_threads[MAX_SMT_THREADS];
0079     struct list_head preempt_list;
0080     spinlock_t lock;
0081     struct rcuwait wait;
0082     spinlock_t stoltb_lock; /* protects stolen_tb and preempt_tb */
0083     u64 stolen_tb;
0084     u64 preempt_tb;
0085     struct kvm_vcpu *runner;
0086     struct kvm *kvm;
0087     u64 tb_offset;      /* guest timebase - host timebase */
0088     u64 tb_offset_applied;  /* timebase offset currently in force */
0089     ulong lpcr;
0090     u32 arch_compat;
0091     ulong pcr;
0092     ulong dpdes;        /* doorbell state (POWER8) */
0093     ulong vtb;      /* virtual timebase */
0094     ulong conferring_threads;
0095     unsigned int halt_poll_ns;
0096     atomic_t online_count;
0097 };
0098
0099 struct kvmppc_vcpu_book3s {
0100     struct kvmppc_sid_map sid_map[SID_MAP_NUM];
0101     struct {
0102         u64 esid;
0103         u64 vsid;
0104     } slb_shadow[64];
0105     u8 slb_shadow_max;
0106     struct kvmppc_bat ibat[8];
0107     struct kvmppc_bat dbat[8];
0108     u64 hid[6];
0109     u64 gqr[8];
0110     u64 sdr1;
0111     u64 hior;
0112     u64 msr_mask;
0113     u64 vtb;
0114 #ifdef CONFIG_PPC_BOOK3S_32
0115     u32 vsid_pool[VSID_POOL_SIZE];
0116     u32 vsid_next;
0117 #else
0118     u64 proto_vsid_first;
0119     u64 proto_vsid_max;
0120     u64 proto_vsid_next;
0121 #endif
0122     int context_id[SID_CONTEXTS];
0123
0124     bool hior_explicit;     /* HIOR is set by ioctl, not PVR */
0125
0126     struct hlist_head hpte_hash_pte[HPTEG_HASH_NUM_PTE];
0127     struct hlist_head hpte_hash_pte_long[HPTEG_HASH_NUM_PTE_LONG];
0128     struct hlist_head hpte_hash_vpte[HPTEG_HASH_NUM_VPTE];
0129     struct hlist_head hpte_hash_vpte_long[HPTEG_HASH_NUM_VPTE_LONG];
0130 #ifdef CONFIG_PPC_BOOK3S_64
0131     struct hlist_head hpte_hash_vpte_64k[HPTEG_HASH_NUM_VPTE_64K];
0132 #endif
0133     int hpte_cache_count;
0134     spinlock_t mmu_lock;
0135 };
0136
0137 #define VSID_REAL   0x07ffffffffc00000ULL
0138 #define VSID_BAT    0x07ffffffffb00000ULL
0139 #define VSID_64K    0x0800000000000000ULL
0140 #define VSID_1T     0x1000000000000000ULL
0141 #define VSID_REAL_DR    0x2000000000000000ULL
0142 #define VSID_REAL_IR    0x4000000000000000ULL
0143 #define VSID_PR     0x8000000000000000ULL
0144
0145 extern void kvmppc_mmu_pte_flush(struct kvm_vcpu *vcpu, ulong ea, ulong ea_mask);
0146 extern void kvmppc_mmu_pte_vflush(struct kvm_vcpu *vcpu, u64 vp, u64 vp_mask);
0147 extern void kvmppc_mmu_pte_pflush(struct kvm_vcpu *vcpu, ulong pa_start, ulong pa_end);
0148 extern void kvmppc_set_msr(struct kvm_vcpu *vcpu, u64 new_msr);
0149 extern void kvmppc_mmu_book3s_64_init(struct kvm_vcpu *vcpu);
0150 extern void kvmppc_mmu_book3s_32_init(struct kvm_vcpu *vcpu);
0151 extern void kvmppc_mmu_book3s_hv_init(struct kvm_vcpu *vcpu);
0152 extern int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *pte,
0153                    bool iswrite);
0154 extern void kvmppc_mmu_unmap_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *pte);
0155 extern int kvmppc_mmu_map_segment(struct kvm_vcpu *vcpu, ulong eaddr);
0156 extern void kvmppc_mmu_flush_segment(struct kvm_vcpu *vcpu, ulong eaddr, ulong seg_size);
0157 extern void kvmppc_mmu_flush_segments(struct kvm_vcpu *vcpu);
0158 extern int kvmppc_book3s_hv_page_fault(struct kvm_vcpu *vcpu,
0159             unsigned long addr, unsigned long status);
0160 extern long kvmppc_hv_find_lock_hpte(struct kvm *kvm, gva_t eaddr,
0161             unsigned long slb_v, unsigned long valid);
0162 extern int kvmppc_hv_emulate_mmio(struct kvm_vcpu *vcpu,
0163             unsigned long gpa, gva_t ea, int is_store);
0164
0165 extern void kvmppc_mmu_hpte_cache_map(struct kvm_vcpu *vcpu, struct hpte_cache *pte);
0166 extern struct hpte_cache *kvmppc_mmu_hpte_cache_next(struct kvm_vcpu *vcpu);
0167 extern void kvmppc_mmu_hpte_cache_free(struct hpte_cache *pte);
0168 extern void kvmppc_mmu_hpte_destroy(struct kvm_vcpu *vcpu);
0169 extern int kvmppc_mmu_hpte_init(struct kvm_vcpu *vcpu);
0170 extern void kvmppc_mmu_invalidate_pte(struct kvm_vcpu *vcpu, struct hpte_cache *pte);
0171 extern int kvmppc_mmu_hpte_sysinit(void);
0172 extern void kvmppc_mmu_hpte_sysexit(void);
0173 extern int kvmppc_mmu_hv_init(void);
0174 extern int kvmppc_book3s_hcall_implemented(struct kvm *kvm, unsigned long hc);
0175
0176 extern int kvmppc_book3s_radix_page_fault(struct kvm_vcpu *vcpu,
0177             unsigned long ea, unsigned long dsisr);
0178 extern unsigned long __kvmhv_copy_tofrom_guest_radix(int lpid, int pid,
0179                     gva_t eaddr, void *to, void *from,
0180                     unsigned long n);
0181 extern long kvmhv_copy_from_guest_radix(struct kvm_vcpu *vcpu, gva_t eaddr,
0182                     void *to, unsigned long n);
0183 extern long kvmhv_copy_to_guest_radix(struct kvm_vcpu *vcpu, gva_t eaddr,
0184                       void *from, unsigned long n);
0185 extern int kvmppc_mmu_walk_radix_tree(struct kvm_vcpu *vcpu, gva_t eaddr,
0186                       struct kvmppc_pte *gpte, u64 root,
0187                       u64 *pte_ret_p);
0188 extern int kvmppc_mmu_radix_translate_table(struct kvm_vcpu *vcpu, gva_t eaddr,
0189             struct kvmppc_pte *gpte, u64 table,
0190             int table_index, u64 *pte_ret_p);
0191 extern int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
0192             struct kvmppc_pte *gpte, bool data, bool iswrite);
0193 extern void kvmppc_radix_tlbie_page(struct kvm *kvm, unsigned long addr,
0194                     unsigned int pshift, unsigned int lpid);
0195 extern void kvmppc_unmap_pte(struct kvm *kvm, pte_t *pte, unsigned long gpa,
0196             unsigned int shift,
0197             const struct kvm_memory_slot *memslot,
0198             unsigned int lpid);
0199 extern bool kvmppc_hv_handle_set_rc(struct kvm *kvm, bool nested,
0200                     bool writing, unsigned long gpa,
0201                     unsigned int lpid);
0202 extern int kvmppc_book3s_instantiate_page(struct kvm_vcpu *vcpu,
0203                 unsigned long gpa,
0204                 struct kvm_memory_slot *memslot,
0205                 bool writing, bool kvm_ro,
0206                 pte_t *inserted_pte, unsigned int *levelp);
0207 extern int kvmppc_init_vm_radix(struct kvm *kvm);
0208 extern void kvmppc_free_radix(struct kvm *kvm);
0209 extern void kvmppc_free_pgtable_radix(struct kvm *kvm, pgd_t *pgd,
0210                       unsigned int lpid);
0211 extern int kvmppc_radix_init(void);
0212 extern void kvmppc_radix_exit(void);
0213 extern void kvm_unmap_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
0214                 unsigned long gfn);
0215 extern bool kvm_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
0216               unsigned long gfn);
0217 extern bool kvm_test_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
0218                    unsigned long gfn);
0219 extern long kvmppc_hv_get_dirty_log_radix(struct kvm *kvm,
0220             struct kvm_memory_slot *memslot, unsigned long *map);
0221 extern void kvmppc_radix_flush_memslot(struct kvm *kvm,
0222             const struct kvm_memory_slot *memslot);
0223 extern int kvmhv_get_rmmu_info(struct kvm *kvm, struct kvm_ppc_rmmu_info *info);
0224
0225 /* XXX remove this export when load_last_inst() is generic */
0226 extern int kvmppc_ld(struct kvm_vcpu *vcpu, ulong *eaddr, int size, void *ptr, bool data);
0227 extern void kvmppc_book3s_queue_irqprio(struct kvm_vcpu *vcpu, unsigned int vec);
0228 extern void kvmppc_book3s_dequeue_irqprio(struct kvm_vcpu *vcpu,
0229                       unsigned int vec);
0230 extern void kvmppc_inject_interrupt(struct kvm_vcpu *vcpu, int vec, u64 flags);
0231 extern void kvmppc_trigger_fac_interrupt(struct kvm_vcpu *vcpu, ulong fac);
0232 extern void kvmppc_set_bat(struct kvm_vcpu *vcpu, struct kvmppc_bat *bat,
0233                bool upper, u32 val);
0234 extern void kvmppc_giveup_ext(struct kvm_vcpu *vcpu, ulong msr);
0235 extern int kvmppc_emulate_paired_single(struct kvm_vcpu *vcpu);
0236 extern kvm_pfn_t kvmppc_gpa_to_pfn(struct kvm_vcpu *vcpu, gpa_t gpa,
0237             bool writing, bool *writable);
0238 extern void kvmppc_add_revmap_chain(struct kvm *kvm, struct revmap_entry *rev,
0239             unsigned long *rmap, long pte_index, int realmode);
0240 extern void kvmppc_update_dirty_map(const struct kvm_memory_slot *memslot,
0241             unsigned long gfn, unsigned long psize);
0242 extern void kvmppc_invalidate_hpte(struct kvm *kvm, __be64 *hptep,
0243             unsigned long pte_index);
0244 void kvmppc_clear_ref_hpte(struct kvm *kvm, __be64 *hptep,
0245             unsigned long pte_index);
0246 extern void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long addr,
0247             unsigned long *nb_ret);
0248 extern void kvmppc_unpin_guest_page(struct kvm *kvm, void *addr,
0249             unsigned long gpa, bool dirty);
0250 extern long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags,
0251             long pte_index, unsigned long pteh, unsigned long ptel,
0252             pgd_t *pgdir, bool realmode, unsigned long *idx_ret);
0253 extern long kvmppc_do_h_remove(struct kvm *kvm, unsigned long flags,
0254             unsigned long pte_index, unsigned long avpn,
0255             unsigned long *hpret);
0256 extern long kvmppc_hv_get_dirty_log_hpt(struct kvm *kvm,
0257             struct kvm_memory_slot *memslot, unsigned long *map);
0258 extern void kvmppc_harvest_vpa_dirty(struct kvmppc_vpa *vpa,
0259             struct kvm_memory_slot *memslot,
0260             unsigned long *map);
0261 extern unsigned long kvmppc_filter_lpcr_hv(struct kvm *kvm,
0262             unsigned long lpcr);
0263 extern void kvmppc_update_lpcr(struct kvm *kvm, unsigned long lpcr,
0264             unsigned long mask);
0265 extern void kvmppc_set_fscr(struct kvm_vcpu *vcpu, u64 fscr);
0266
0267 extern int kvmhv_p9_tm_emulation_early(struct kvm_vcpu *vcpu);
0268 extern int kvmhv_p9_tm_emulation(struct kvm_vcpu *vcpu);
0269 extern void kvmhv_emulate_tm_rollback(struct kvm_vcpu *vcpu);
0270
0271 extern void kvmppc_entry_trampoline(void);
0272 extern void kvmppc_hv_entry_trampoline(void);
0273 extern u32 kvmppc_alignment_dsisr(struct kvm_vcpu *vcpu, unsigned int inst);
0274 extern ulong kvmppc_alignment_dar(struct kvm_vcpu *vcpu, unsigned int inst);
0275 extern int kvmppc_h_pr(struct kvm_vcpu *vcpu, unsigned long cmd);
0276 extern void kvmppc_pr_init_default_hcalls(struct kvm *kvm);
0277 extern int kvmppc_hcall_impl_pr(unsigned long cmd);
0278 extern int kvmppc_hcall_impl_hv_realmode(unsigned long cmd);
0279 extern void kvmppc_copy_to_svcpu(struct kvm_vcpu *vcpu);
0280 extern void kvmppc_copy_from_svcpu(struct kvm_vcpu *vcpu);
0281
0282 long kvmppc_read_intr(void);
0283 void kvmppc_set_msr_hv(struct kvm_vcpu *vcpu, u64 msr);
0284 void kvmppc_inject_interrupt_hv(struct kvm_vcpu *vcpu, int vec, u64 srr1_flags);
0285
0286 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
0287 void kvmppc_save_tm_pr(struct kvm_vcpu *vcpu);
0288 void kvmppc_restore_tm_pr(struct kvm_vcpu *vcpu);
0289 void kvmppc_save_tm_sprs(struct kvm_vcpu *vcpu);
0290 void kvmppc_restore_tm_sprs(struct kvm_vcpu *vcpu);
0291 #else
0292 static inline void kvmppc_save_tm_pr(struct kvm_vcpu *vcpu) {}
0293 static inline void kvmppc_restore_tm_pr(struct kvm_vcpu *vcpu) {}
0294 static inline void kvmppc_save_tm_sprs(struct kvm_vcpu *vcpu) {}
0295 static inline void kvmppc_restore_tm_sprs(struct kvm_vcpu *vcpu) {}
0296 #endif
0297
0298 long kvmhv_nested_init(void);
0299 void kvmhv_nested_exit(void);
0300 void kvmhv_vm_nested_init(struct kvm *kvm);
0301 long kvmhv_set_partition_table(struct kvm_vcpu *vcpu);
0302 long kvmhv_copy_tofrom_guest_nested(struct kvm_vcpu *vcpu);
0303 void kvmhv_set_ptbl_entry(unsigned int lpid, u64 dw0, u64 dw1);
0304 void kvmhv_release_all_nested(struct kvm *kvm);
0305 long kvmhv_enter_nested_guest(struct kvm_vcpu *vcpu);
0306 long kvmhv_do_nested_tlbie(struct kvm_vcpu *vcpu);
0307 long do_h_rpt_invalidate_pat(struct kvm_vcpu *vcpu, unsigned long lpid,
0308                  unsigned long type, unsigned long pg_sizes,
0309                  unsigned long start, unsigned long end);
0310 int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu,
0311               u64 time_limit, unsigned long lpcr);
0312 void kvmhv_save_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr);
0313 void kvmhv_restore_hv_return_state(struct kvm_vcpu *vcpu,
0314                    struct hv_guest_state *hr);
0315 long int kvmhv_nested_page_fault(struct kvm_vcpu *vcpu);
0316
0317 void kvmppc_giveup_fac(struct kvm_vcpu *vcpu, ulong fac);
0318
0319 extern int kvm_irq_bypass;
0320
0321 static inline struct kvmppc_vcpu_book3s *to_book3s(struct kvm_vcpu *vcpu)
0322 {
0323     return vcpu->arch.book3s;
0324 }
0325
0326 /* Also add subarch specific defines */
0327
0328 #ifdef CONFIG_KVM_BOOK3S_32_HANDLER
0329 #include <asm/kvm_book3s_32.h>
0330 #endif
0331 #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
0332 #include <asm/kvm_book3s_64.h>
0333 #endif
0334
0335 static inline void kvmppc_set_gpr(struct kvm_vcpu *vcpu, int num, ulong val)
0336 {
0337     vcpu->arch.regs.gpr[num] = val;
0338 }
0339
0340 static inline ulong kvmppc_get_gpr(struct kvm_vcpu *vcpu, int num)
0341 {
0342     return vcpu->arch.regs.gpr[num];
0343 }
0344
0345 static inline void kvmppc_set_cr(struct kvm_vcpu *vcpu, u32 val)
0346 {
0347     vcpu->arch.regs.ccr = val;
0348 }
0349
0350 static inline u32 kvmppc_get_cr(struct kvm_vcpu *vcpu)
0351 {
0352     return vcpu->arch.regs.ccr;
0353 }
0354
0355 static inline void kvmppc_set_xer(struct kvm_vcpu *vcpu, ulong val)
0356 {
0357     vcpu->arch.regs.xer = val;
0358 }
0359
0360 static inline ulong kvmppc_get_xer(struct kvm_vcpu *vcpu)
0361 {
0362     return vcpu->arch.regs.xer;
0363 }
0364
0365 static inline void kvmppc_set_ctr(struct kvm_vcpu *vcpu, ulong val)
0366 {
0367     vcpu->arch.regs.ctr = val;
0368 }
0369
0370 static inline ulong kvmppc_get_ctr(struct kvm_vcpu *vcpu)
0371 {
0372     return vcpu->arch.regs.ctr;
0373 }
0374
0375 static inline void kvmppc_set_lr(struct kvm_vcpu *vcpu, ulong val)
0376 {
0377     vcpu->arch.regs.link = val;
0378 }
0379
0380 static inline ulong kvmppc_get_lr(struct kvm_vcpu *vcpu)
0381 {
0382     return vcpu->arch.regs.link;
0383 }
0384
0385 static inline void kvmppc_set_pc(struct kvm_vcpu *vcpu, ulong val)
0386 {
0387     vcpu->arch.regs.nip = val;
0388 }
0389
0390 static inline ulong kvmppc_get_pc(struct kvm_vcpu *vcpu)
0391 {
0392     return vcpu->arch.regs.nip;
0393 }
0394
0395 static inline u64 kvmppc_get_msr(struct kvm_vcpu *vcpu);
0396 static inline bool kvmppc_need_byteswap(struct kvm_vcpu *vcpu)
0397 {
0398     return (kvmppc_get_msr(vcpu) & MSR_LE) != (MSR_KERNEL & MSR_LE);
0399 }
0400
0401 static inline ulong kvmppc_get_fault_dar(struct kvm_vcpu *vcpu)
0402 {
0403     return vcpu->arch.fault_dar;
0404 }
0405
0406 /* Expiry time of vcpu DEC relative to host TB */
0407 static inline u64 kvmppc_dec_expires_host_tb(struct kvm_vcpu *vcpu)
0408 {
0409     return vcpu->arch.dec_expires - vcpu->arch.vcore->tb_offset;
0410 }
0411
0412 static inline bool is_kvmppc_resume_guest(int r)
0413 {
0414     return (r == RESUME_GUEST || r == RESUME_GUEST_NV);
0415 }
0416
0417 static inline bool is_kvmppc_hv_enabled(struct kvm *kvm);
0418 static inline bool kvmppc_supports_magic_page(struct kvm_vcpu *vcpu)
0419 {
0420     /* Only PR KVM supports the magic page */
0421     return !is_kvmppc_hv_enabled(vcpu->kvm);
0422 }
0423
0424 extern int kvmppc_h_logical_ci_load(struct kvm_vcpu *vcpu);
0425 extern int kvmppc_h_logical_ci_store(struct kvm_vcpu *vcpu);
0426
0427 /* Magic register values loaded into r3 and r4 before the 'sc' assembly
0428  * instruction for the OSI hypercalls */
0429 #define OSI_SC_MAGIC_R3         0x113724FA
0430 #define OSI_SC_MAGIC_R4         0x77810F9B
0431
0432 #define INS_DCBZ            0x7c0007ec
0433 /* TO = 31 for unconditional trap */
0434 #define INS_TW              0x7fe00008
0435
0436 #define SPLIT_HACK_MASK         0xff000000
0437 #define SPLIT_HACK_OFFS         0xfb000000
0438
0439 /*
0440  * This packs a VCPU ID from the [0..KVM_MAX_VCPU_IDS) space down to the
0441  * [0..KVM_MAX_VCPUS) space, using knowledge of the guest's core stride
0442  * (but not its actual threading mode, which is not available) to avoid
0443  * collisions.
0444  *
0445  * The implementation leaves VCPU IDs from the range [0..KVM_MAX_VCPUS) (block
0446  * 0) unchanged: if the guest is filling each VCORE completely then it will be
0447  * using consecutive IDs and it will fill the space without any packing.
0448  *
0449  * For higher VCPU IDs, the packed ID is based on the VCPU ID modulo
0450  * KVM_MAX_VCPUS (effectively masking off the top bits) and then an offset is
0451  * added to avoid collisions.
0452  *
0453  * VCPU IDs in the range [KVM_MAX_VCPUS..(KVM_MAX_VCPUS*2)) (block 1) are only
0454  * possible if the guest is leaving at least 1/2 of each VCORE empty, so IDs
0455  * can be safely packed into the second half of each VCORE by adding an offset
0456  * of (stride / 2).
0457  *
0458  * Similarly, if VCPU IDs in the range [(KVM_MAX_VCPUS*2)..(KVM_MAX_VCPUS*4))
0459  * (blocks 2 and 3) are seen, the guest must be leaving at least 3/4 of each
0460  * VCORE empty so packed IDs can be offset by (stride / 4) and (stride * 3 / 4).
0461  *
0462  * Finally, VCPU IDs from blocks 5..7 will only be seen if the guest is using a
0463  * stride of 8 and 1 thread per core so the remaining offsets of 1, 5, 3 and 7
0464  * must be free to use.
0465  *
0466  * (The offsets for each block are stored in block_offsets[], indexed by the
0467  * block number if the stride is 8. For cases where the guest's stride is less
0468  * than 8, we can re-use the block_offsets array by multiplying the block
0469  * number by (MAX_SMT_THREADS / stride) to reach the correct entry.)
0470  */
0471 static inline u32 kvmppc_pack_vcpu_id(struct kvm *kvm, u32 id)
0472 {
0473     const int block_offsets[MAX_SMT_THREADS] = {0, 4, 2, 6, 1, 5, 3, 7};
0474     int stride = kvm->arch.emul_smt_mode;
0475     int block = (id / KVM_MAX_VCPUS) * (MAX_SMT_THREADS / stride);
0476     u32 packed_id;
0477
0478     if (WARN_ONCE(block >= MAX_SMT_THREADS, "VCPU ID too large to pack"))
0479         return 0;
0480     packed_id = (id % KVM_MAX_VCPUS) + block_offsets[block];
0481     if (WARN_ONCE(packed_id >= KVM_MAX_VCPUS, "VCPU ID packing failed"))
0482         return 0;
0483     return packed_id;
0484 }
0485
0486 #endif /* __ASM_KVM_BOOK3S_H__ */