arch/powerpc/include/asm/kvm_book3s_64.h

   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 SUSE Linux Products GmbH 2010
  16  *
  17  * Authors: Alexander Graf <agraf@suse.de>
  18  */
  19
  20 #ifndef __ASM_KVM_BOOK3S_64_H__
  21 #define __ASM_KVM_BOOK3S_64_H__
  22
  23 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
  24 static inline struct kvmppc_book3s_shadow_vcpu *svcpu_get(struct kvm_vcpu *vcpu)
  25 {
  26         preempt_disable();
  27         return &get_paca()->shadow_vcpu;
  28 }
  29
  30 static inline void svcpu_put(struct kvmppc_book3s_shadow_vcpu *svcpu)
  31 {
  32         preempt_enable();
  33 }
  34 #endif
  35
  36 #define SPAPR_TCE_SHIFT         12
  37
  38 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
  39 #define KVM_DEFAULT_HPT_ORDER   24      /* 16MB HPT by default */
  40 extern unsigned long kvm_rma_pages;
  41 #endif
  42
  43 #define VRMA_VSID       0x1ffffffUL     /* 1TB VSID reserved for VRMA */
  44
  45 /*
  46  * We use a lock bit in HPTE dword 0 to synchronize updates and
  47  * accesses to each HPTE, and another bit to indicate non-present
  48  * HPTEs.
  49  */
  50 #define HPTE_V_HVLOCK   0x40UL
  51 #define HPTE_V_ABSENT   0x20UL
  52
  53 /*
  54  * We use this bit in the guest_rpte field of the revmap entry
  55  * to indicate a modified HPTE.
  56  */
  57 #define HPTE_GR_MODIFIED        (1ul << 62)
  58
  59 /* These bits are reserved in the guest view of the HPTE */
  60 #define HPTE_GR_RESERVED        HPTE_GR_MODIFIED
  61
  62 static inline long try_lock_hpte(unsigned long *hpte, unsigned long bits)
  63 {
  64         unsigned long tmp, old;
  65
  66         asm volatile("  ldarx   %0,0,%2\n"
  67                      "  and.    %1,%0,%3\n"
  68                      "  bne     2f\n"
  69                      "  ori     %0,%0,%4\n"
  70                      "  stdcx.  %0,0,%2\n"
  71                      "  beq+    2f\n"
  72                      "  mr      %1,%3\n"
  73                      "2:        isync"
  74                      : "=&r" (tmp), "=&r" (old)
  75                      : "r" (hpte), "r" (bits), "i" (HPTE_V_HVLOCK)
  76                      : "cc", "memory");
  77         return old == 0;
  78 }
  79
  80 static inline unsigned long compute_tlbie_rb(unsigned long v, unsigned long r,
  81                                              unsigned long pte_index)
  82 {
  83         unsigned long rb, va_low;
  84
  85         rb = (v & ~0x7fUL) << 16;               /* AVA field */
  86         va_low = pte_index >> 3;
  87         if (v & HPTE_V_SECONDARY)
  88                 va_low = ~va_low;
  89         /* xor vsid from AVA */
  90         if (!(v & HPTE_V_1TB_SEG))
  91                 va_low ^= v >> 12;
  92         else
  93                 va_low ^= v >> 24;
  94         va_low &= 0x7ff;
  95         if (v & HPTE_V_LARGE) {
  96                 rb |= 1;                        /* L field */
  97                 if (cpu_has_feature(CPU_FTR_ARCH_206) &&
  98                     (r & 0xff000)) {
  99                         /* non-16MB large page, must be 64k */
 100                         /* (masks depend on page size) */
 101                         rb |= 0x1000;           /* page encoding in LP field */
 102                         rb |= (va_low & 0x7f) << 16; /* 7b of VA in AVA/LP field */
 103                         rb |= ((va_low << 4) & 0xf0);   /* AVAL field (P7 doesn't seem to care) */
 104                 }
 105         } else {
 106                 /* 4kB page */
 107                 rb |= (va_low & 0x7ff) << 12;   /* remaining 11b of VA */
 108         }
 109         rb |= (v >> 54) & 0x300;                /* B field */
 110         return rb;
 111 }
 112
 113 static inline unsigned long hpte_page_size(unsigned long h, unsigned long l)
 114 {
 115         /* only handle 4k, 64k and 16M pages for now */
 116         if (!(h & HPTE_V_LARGE))
 117                 return 1ul << 12;               /* 4k page */
 118         if ((l & 0xf000) == 0x1000 && cpu_has_feature(CPU_FTR_ARCH_206))
 119                 return 1ul << 16;               /* 64k page */
 120         if ((l & 0xff000) == 0)
 121                 return 1ul << 24;               /* 16M page */
 122         return 0;                               /* error */
 123 }
 124
 125 static inline unsigned long hpte_rpn(unsigned long ptel, unsigned long psize)
 126 {
 127         return ((ptel & HPTE_R_RPN) & ~(psize - 1)) >> PAGE_SHIFT;
 128 }
 129
 130 static inline int hpte_is_writable(unsigned long ptel)
 131 {
 132         unsigned long pp = ptel & (HPTE_R_PP0 | HPTE_R_PP);
 133
 134         return pp != PP_RXRX && pp != PP_RXXX;
 135 }
 136
 137 static inline unsigned long hpte_make_readonly(unsigned long ptel)
 138 {
 139         if ((ptel & HPTE_R_PP0) || (ptel & HPTE_R_PP) == PP_RWXX)
 140                 ptel = (ptel & ~HPTE_R_PP) | PP_RXXX;
 141         else
 142                 ptel |= PP_RXRX;
 143         return ptel;
 144 }
 145
 146 static inline int hpte_cache_flags_ok(unsigned long ptel, unsigned long io_type)
 147 {
 148         unsigned int wimg = ptel & HPTE_R_WIMG;
 149
 150         /* Handle SAO */
 151         if (wimg == (HPTE_R_W | HPTE_R_I | HPTE_R_M) &&
 152             cpu_has_feature(CPU_FTR_ARCH_206))
 153                 wimg = HPTE_R_M;
 154
 155         if (!io_type)
 156                 return wimg == HPTE_R_M;
 157
 158         return (wimg & (HPTE_R_W | HPTE_R_I)) == io_type;
 159 }
 160
 161 /*
 162  * If it's present and writable, atomically set dirty and referenced bits and
 163  * return the PTE, otherwise return 0. If we find a transparent hugepage
 164  * and if it is marked splitting we return 0;
 165  */
 166 static inline pte_t kvmppc_read_update_linux_pte(pte_t *ptep, int writing,
 167                                                  unsigned int hugepage)
 168 {
 169         pte_t old_pte, new_pte = __pte(0);
 170
 171         while (1) {
 172                 old_pte = pte_val(*ptep);
 173                 /*
 174                  * wait until _PAGE_BUSY is clear then set it atomically
 175                  */
 176                 if (unlikely(old_pte & _PAGE_BUSY)) {
 177                         cpu_relax();
 178                         continue;
 179                 }
 180 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 181                 /* If hugepage and is trans splitting return None */
 182                 if (unlikely(hugepage &&
 183                              pmd_trans_splitting(pte_pmd(old_pte))))
 184                         return __pte(0);
 185 #endif
 186                 /* If pte is not present return None */
 187                 if (unlikely(!(old_pte & _PAGE_PRESENT)))
 188                         return __pte(0);
 189
 190                 new_pte = pte_mkyoung(old_pte);
 191                 if (writing && pte_write(old_pte))
 192                         new_pte = pte_mkdirty(new_pte);
 193
 194                 if (old_pte == __cmpxchg_u64((unsigned long *)ptep, old_pte,
 195                                              new_pte))
 196                         break;
 197         }
 198         return new_pte;
 199 }
 200
 201
 202 /* Return HPTE cache control bits corresponding to Linux pte bits */
 203 static inline unsigned long hpte_cache_bits(unsigned long pte_val)
 204 {
 205 #if _PAGE_NO_CACHE == HPTE_R_I && _PAGE_WRITETHRU == HPTE_R_W
 206         return pte_val & (HPTE_R_W | HPTE_R_I);
 207 #else
 208         return ((pte_val & _PAGE_NO_CACHE) ? HPTE_R_I : 0) +
 209                 ((pte_val & _PAGE_WRITETHRU) ? HPTE_R_W : 0);
 210 #endif
 211 }
 212
 213 static inline bool hpte_read_permission(unsigned long pp, unsigned long key)
 214 {
 215         if (key)
 216                 return PP_RWRX <= pp && pp <= PP_RXRX;
 217         return 1;
 218 }
 219
 220 static inline bool hpte_write_permission(unsigned long pp, unsigned long key)
 221 {
 222         if (key)
 223                 return pp == PP_RWRW;
 224         return pp <= PP_RWRW;
 225 }
 226
 227 static inline int hpte_get_skey_perm(unsigned long hpte_r, unsigned long amr)
 228 {
 229         unsigned long skey;
 230
 231         skey = ((hpte_r & HPTE_R_KEY_HI) >> 57) |
 232                 ((hpte_r & HPTE_R_KEY_LO) >> 9);
 233         return (amr >> (62 - 2 * skey)) & 3;
 234 }
 235
 236 static inline void lock_rmap(unsigned long *rmap)
 237 {
 238         do {
 239                 while (test_bit(KVMPPC_RMAP_LOCK_BIT, rmap))
 240                         cpu_relax();
 241         } while (test_and_set_bit_lock(KVMPPC_RMAP_LOCK_BIT, rmap));
 242 }
 243
 244 static inline void unlock_rmap(unsigned long *rmap)
 245 {
 246         __clear_bit_unlock(KVMPPC_RMAP_LOCK_BIT, rmap);
 247 }
 248
 249 static inline bool slot_is_aligned(struct kvm_memory_slot *memslot,
 250                                    unsigned long pagesize)
 251 {
 252         unsigned long mask = (pagesize >> PAGE_SHIFT) - 1;
 253
 254         if (pagesize <= PAGE_SIZE)
 255                 return 1;
 256         return !(memslot->base_gfn & mask) && !(memslot->npages & mask);
 257 }
 258
 259 /*
 260  * This works for 4k, 64k and 16M pages on POWER7,
 261  * and 4k and 16M pages on PPC970.
 262  */
 263 static inline unsigned long slb_pgsize_encoding(unsigned long psize)
 264 {
 265         unsigned long senc = 0;
 266
 267         if (psize > 0x1000) {
 268                 senc = SLB_VSID_L;
 269                 if (psize == 0x10000)
 270                         senc |= SLB_VSID_LP_01;
 271         }
 272         return senc;
 273 }
 274
 275 static inline int is_vrma_hpte(unsigned long hpte_v)
 276 {
 277         return (hpte_v & ~0xffffffUL) ==
 278                 (HPTE_V_1TB_SEG | (VRMA_VSID << (40 - 16)));
 279 }
 280
 281 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
 282 /*
 283  * Note modification of an HPTE; set the HPTE modified bit
 284  * if anyone is interested.
 285  */
 286 static inline void note_hpte_modification(struct kvm *kvm,
 287                                           struct revmap_entry *rev)
 288 {
 289         if (atomic_read(&kvm->arch.hpte_mod_interest))
 290                 rev->guest_rpte |= HPTE_GR_MODIFIED;
 291 }
 292 #endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */
 293
 294 #endif /* __ASM_KVM_BOOK3S_64_H__ */