arch/powerpc/kvm/book3s_64_mmu_hv.c

   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 2010 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
  16  */
  17
  18 #include <linux/types.h>
  19 #include <linux/string.h>
  20 #include <linux/kvm.h>
  21 #include <linux/kvm_host.h>
  22 #include <linux/highmem.h>
  23 #include <linux/gfp.h>
  24 #include <linux/slab.h>
  25 #include <linux/hugetlb.h>
  26
  27 #include <asm/tlbflush.h>
  28 #include <asm/kvm_ppc.h>
  29 #include <asm/kvm_book3s.h>
  30 #include <asm/mmu-hash64.h>
  31 #include <asm/hvcall.h>
  32 #include <asm/synch.h>
  33 #include <asm/ppc-opcode.h>
  34 #include <asm/cputable.h>
  35
  36 /* For now use fixed-size 16MB page table */
  37 #define HPT_ORDER       24
  38 #define HPT_NPTEG       (1ul << (HPT_ORDER - 7))        /* 128B per pteg */
  39 #define HPT_HASH_MASK   (HPT_NPTEG - 1)
  40
  41 /* Pages in the VRMA are 16MB pages */
  42 #define VRMA_PAGE_ORDER 24
  43 #define VRMA_VSID       0x1ffffffUL     /* 1TB VSID reserved for VRMA */
  44
  45 /* POWER7 has 10-bit LPIDs, PPC970 has 6-bit LPIDs */
  46 #define MAX_LPID_970    63
  47 #define NR_LPIDS        (LPID_RSVD + 1)
  48 unsigned long lpid_inuse[BITS_TO_LONGS(NR_LPIDS)];
  49
  50 long kvmppc_alloc_hpt(struct kvm *kvm)
  51 {
  52         unsigned long hpt;
  53         unsigned long lpid;
  54
  55         hpt = __get_free_pages(GFP_KERNEL|__GFP_ZERO|__GFP_REPEAT|__GFP_NOWARN,
  56                                HPT_ORDER - PAGE_SHIFT);
  57         if (!hpt) {
  58                 pr_err("kvm_alloc_hpt: Couldn't alloc HPT\n");
  59                 return -ENOMEM;
  60         }
  61         kvm->arch.hpt_virt = hpt;
  62
  63         do {
  64                 lpid = find_first_zero_bit(lpid_inuse, NR_LPIDS);
  65                 if (lpid >= NR_LPIDS) {
  66                         pr_err("kvm_alloc_hpt: No LPIDs free\n");
  67                         free_pages(hpt, HPT_ORDER - PAGE_SHIFT);
  68                         return -ENOMEM;
  69                 }
  70         } while (test_and_set_bit(lpid, lpid_inuse));
  71
  72         kvm->arch.sdr1 = __pa(hpt) | (HPT_ORDER - 18);
  73         kvm->arch.lpid = lpid;
  74
  75         pr_info("KVM guest htab at %lx, LPID %lx\n", hpt, lpid);
  76         return 0;
  77 }
  78
  79 void kvmppc_free_hpt(struct kvm *kvm)
  80 {
  81         clear_bit(kvm->arch.lpid, lpid_inuse);
  82         free_pages(kvm->arch.hpt_virt, HPT_ORDER - PAGE_SHIFT);
  83 }
  84
  85 void kvmppc_map_vrma(struct kvm *kvm, struct kvm_userspace_memory_region *mem)
  86 {
  87         unsigned long i;
  88         unsigned long npages = kvm->arch.ram_npages;
  89         unsigned long pfn;
  90         unsigned long *hpte;
  91         unsigned long hash;
  92         struct kvmppc_pginfo *pginfo = kvm->arch.ram_pginfo;
  93
  94         if (!pginfo)
  95                 return;
  96
  97         /* VRMA can't be > 1TB */
  98         if (npages > 1ul << (40 - kvm->arch.ram_porder))
  99                 npages = 1ul << (40 - kvm->arch.ram_porder);
 100         /* Can't use more than 1 HPTE per HPTEG */
 101         if (npages > HPT_NPTEG)
 102                 npages = HPT_NPTEG;
 103
 104         for (i = 0; i < npages; ++i) {
 105                 pfn = pginfo[i].pfn;
 106                 if (!pfn)
 107                         break;
 108                 /* can't use hpt_hash since va > 64 bits */
 109                 hash = (i ^ (VRMA_VSID ^ (VRMA_VSID << 25))) & HPT_HASH_MASK;
 110                 /*
 111                  * We assume that the hash table is empty and no
 112                  * vcpus are using it at this stage.  Since we create
 113                  * at most one HPTE per HPTEG, we just assume entry 7
 114                  * is available and use it.
 115                  */
 116                 hpte = (unsigned long *) (kvm->arch.hpt_virt + (hash << 7));
 117                 hpte += 7 * 2;
 118                 /* HPTE low word - RPN, protection, etc. */
 119                 hpte[1] = (pfn << PAGE_SHIFT) | HPTE_R_R | HPTE_R_C |
 120                         HPTE_R_M | PP_RWXX;
 121                 wmb();
 122                 hpte[0] = HPTE_V_1TB_SEG | (VRMA_VSID << (40 - 16)) |
 123                         (i << (VRMA_PAGE_ORDER - 16)) | HPTE_V_BOLTED |
 124                         HPTE_V_LARGE | HPTE_V_VALID;
 125         }
 126 }
 127
 128 int kvmppc_mmu_hv_init(void)
 129 {
 130         unsigned long host_lpid, rsvd_lpid;
 131
 132         if (!cpu_has_feature(CPU_FTR_HVMODE))
 133                 return -EINVAL;
 134
 135         memset(lpid_inuse, 0, sizeof(lpid_inuse));
 136
 137         if (cpu_has_feature(CPU_FTR_ARCH_206)) {
 138                 host_lpid = mfspr(SPRN_LPID);   /* POWER7 */
 139                 rsvd_lpid = LPID_RSVD;
 140         } else {
 141                 host_lpid = 0;                  /* PPC970 */
 142                 rsvd_lpid = MAX_LPID_970;
 143         }
 144
 145         set_bit(host_lpid, lpid_inuse);
 146         /* rsvd_lpid is reserved for use in partition switching */
 147         set_bit(rsvd_lpid, lpid_inuse);
 148
 149         return 0;
 150 }
 151
 152 void kvmppc_mmu_destroy(struct kvm_vcpu *vcpu)
 153 {
 154 }
 155
 156 static void kvmppc_mmu_book3s_64_hv_reset_msr(struct kvm_vcpu *vcpu)
 157 {
 158         kvmppc_set_msr(vcpu, MSR_SF | MSR_ME);
 159 }
 160
 161 static int kvmppc_mmu_book3s_64_hv_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
 162                                 struct kvmppc_pte *gpte, bool data)
 163 {
 164         return -ENOENT;
 165 }
 166
 167 void kvmppc_mmu_book3s_hv_init(struct kvm_vcpu *vcpu)
 168 {
 169         struct kvmppc_mmu *mmu = &vcpu->arch.mmu;
 170
 171         if (cpu_has_feature(CPU_FTR_ARCH_206))
 172                 vcpu->arch.slb_nr = 32;         /* POWER7 */
 173         else
 174                 vcpu->arch.slb_nr = 64;
 175
 176         mmu->xlate = kvmppc_mmu_book3s_64_hv_xlate;
 177         mmu->reset_msr = kvmppc_mmu_book3s_64_hv_reset_msr;
 178
 179         vcpu->arch.hflags |= BOOK3S_HFLAG_SLB;
 180 }