linux_dsm_epyc7002/arch/powerpc/include/asm/kvm_book3s_64.h
Paul Mackerras 8dc6cca556 KVM: PPC: Book3S HV: Don't rely on host's page size information
This removes the dependence of KVM on the mmu_psize_defs array (which
stores information about hardware support for various page sizes) and
the things derived from it, chiefly hpte_page_sizes[], hpte_page_size(),
hpte_actual_page_size() and get_sllp_encoding().  We also no longer
rely on the mmu_slb_size variable or the MMU_FTR_1T_SEGMENTS feature
bit.

The reason for doing this is so we can support a HPT guest on a radix
host.  In a radix host, the mmu_psize_defs array contains information
about page sizes supported by the MMU in radix mode rather than the
page sizes supported by the MMU in HPT mode.  Similarly, mmu_slb_size
and the MMU_FTR_1T_SEGMENTS bit are not set.

Instead we hard-code knowledge of the behaviour of the HPT MMU in the
POWER7, POWER8 and POWER9 processors (which are the only processors
supported by HV KVM) - specifically the encoding of the LP fields in
the HPT and SLB entries, and the fact that they have 32 SLB entries
and support 1TB segments.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-11-01 15:36:06 +11:00

450 lines
11 KiB
C

/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License, version 2, as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* Copyright SUSE Linux Products GmbH 2010
*
* Authors: Alexander Graf <agraf@suse.de>
*/
#ifndef __ASM_KVM_BOOK3S_64_H__
#define __ASM_KVM_BOOK3S_64_H__
#include <asm/book3s/64/mmu-hash.h>
/* Power architecture requires HPT is at least 256kiB, at most 64TiB */
#define PPC_MIN_HPT_ORDER 18
#define PPC_MAX_HPT_ORDER 46
#ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
static inline struct kvmppc_book3s_shadow_vcpu *svcpu_get(struct kvm_vcpu *vcpu)
{
preempt_disable();
return &get_paca()->shadow_vcpu;
}
static inline void svcpu_put(struct kvmppc_book3s_shadow_vcpu *svcpu)
{
preempt_enable();
}
#endif
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
static inline bool kvm_is_radix(struct kvm *kvm)
{
return kvm->arch.radix;
}
#define KVM_DEFAULT_HPT_ORDER 24 /* 16MB HPT by default */
#endif
/*
* We use a lock bit in HPTE dword 0 to synchronize updates and
* accesses to each HPTE, and another bit to indicate non-present
* HPTEs.
*/
#define HPTE_V_HVLOCK 0x40UL
#define HPTE_V_ABSENT 0x20UL
/*
* We use this bit in the guest_rpte field of the revmap entry
* to indicate a modified HPTE.
*/
#define HPTE_GR_MODIFIED (1ul << 62)
/* These bits are reserved in the guest view of the HPTE */
#define HPTE_GR_RESERVED HPTE_GR_MODIFIED
static inline long try_lock_hpte(__be64 *hpte, unsigned long bits)
{
unsigned long tmp, old;
__be64 be_lockbit, be_bits;
/*
* We load/store in native endian, but the HTAB is in big endian. If
* we byte swap all data we apply on the PTE we're implicitly correct
* again.
*/
be_lockbit = cpu_to_be64(HPTE_V_HVLOCK);
be_bits = cpu_to_be64(bits);
asm volatile(" ldarx %0,0,%2\n"
" and. %1,%0,%3\n"
" bne 2f\n"
" or %0,%0,%4\n"
" stdcx. %0,0,%2\n"
" beq+ 2f\n"
" mr %1,%3\n"
"2: isync"
: "=&r" (tmp), "=&r" (old)
: "r" (hpte), "r" (be_bits), "r" (be_lockbit)
: "cc", "memory");
return old == 0;
}
static inline void unlock_hpte(__be64 *hpte, unsigned long hpte_v)
{
hpte_v &= ~HPTE_V_HVLOCK;
asm volatile(PPC_RELEASE_BARRIER "" : : : "memory");
hpte[0] = cpu_to_be64(hpte_v);
}
/* Without barrier */
static inline void __unlock_hpte(__be64 *hpte, unsigned long hpte_v)
{
hpte_v &= ~HPTE_V_HVLOCK;
hpte[0] = cpu_to_be64(hpte_v);
}
/*
* These functions encode knowledge of the POWER7/8/9 hardware
* interpretations of the HPTE LP (large page size) field.
*/
static inline int kvmppc_hpte_page_shifts(unsigned long h, unsigned long l)
{
unsigned int lphi;
if (!(h & HPTE_V_LARGE))
return 12; /* 4kB */
lphi = (l >> 16) & 0xf;
switch ((l >> 12) & 0xf) {
case 0:
return !lphi ? 24 : -1; /* 16MB */
break;
case 1:
return 16; /* 64kB */
break;
case 3:
return !lphi ? 34 : -1; /* 16GB */
break;
case 7:
return (16 << 8) + 12; /* 64kB in 4kB */
break;
case 8:
if (!lphi)
return (24 << 8) + 16; /* 16MB in 64kkB */
if (lphi == 3)
return (24 << 8) + 12; /* 16MB in 4kB */
break;
}
return -1;
}
static inline int kvmppc_hpte_base_page_shift(unsigned long h, unsigned long l)
{
return kvmppc_hpte_page_shifts(h, l) & 0xff;
}
static inline int kvmppc_hpte_actual_page_shift(unsigned long h, unsigned long l)
{
int tmp = kvmppc_hpte_page_shifts(h, l);
if (tmp >= 0x100)
tmp >>= 8;
return tmp;
}
static inline unsigned long kvmppc_actual_pgsz(unsigned long v, unsigned long r)
{
return 1ul << kvmppc_hpte_actual_page_shift(v, r);
}
static inline int kvmppc_pgsize_lp_encoding(int base_shift, int actual_shift)
{
switch (base_shift) {
case 12:
switch (actual_shift) {
case 12:
return 0;
case 16:
return 7;
case 24:
return 0x38;
}
break;
case 16:
switch (actual_shift) {
case 16:
return 1;
case 24:
return 8;
}
break;
case 24:
return 0;
}
return -1;
}
static inline unsigned long compute_tlbie_rb(unsigned long v, unsigned long r,
unsigned long pte_index)
{
int a_pgshift, b_pgshift;
unsigned long rb = 0, va_low, sllp;
b_pgshift = a_pgshift = kvmppc_hpte_page_shifts(v, r);
if (a_pgshift >= 0x100) {
b_pgshift &= 0xff;
a_pgshift >>= 8;
}
/*
* Ignore the top 14 bits of va
* v have top two bits covering segment size, hence move
* by 16 bits, Also clear the lower HPTE_V_AVPN_SHIFT (7) bits.
* AVA field in v also have the lower 23 bits ignored.
* For base page size 4K we need 14 .. 65 bits (so need to
* collect extra 11 bits)
* For others we need 14..14+i
*/
/* This covers 14..54 bits of va*/
rb = (v & ~0x7fUL) << 16; /* AVA field */
/*
* AVA in v had cleared lower 23 bits. We need to derive
* that from pteg index
*/
va_low = pte_index >> 3;
if (v & HPTE_V_SECONDARY)
va_low = ~va_low;
/*
* get the vpn bits from va_low using reverse of hashing.
* In v we have va with 23 bits dropped and then left shifted
* HPTE_V_AVPN_SHIFT (7) bits. Now to find vsid we need
* right shift it with (SID_SHIFT - (23 - 7))
*/
if (!(v & HPTE_V_1TB_SEG))
va_low ^= v >> (SID_SHIFT - 16);
else
va_low ^= v >> (SID_SHIFT_1T - 16);
va_low &= 0x7ff;
if (b_pgshift == 12) {
if (a_pgshift > 12) {
sllp = (a_pgshift == 16) ? 5 : 4;
rb |= sllp << 5; /* AP field */
}
rb |= (va_low & 0x7ff) << 12; /* remaining 11 bits of AVA */
} else {
int aval_shift;
/*
* remaining bits of AVA/LP fields
* Also contain the rr bits of LP
*/
rb |= (va_low << b_pgshift) & 0x7ff000;
/*
* Now clear not needed LP bits based on actual psize
*/
rb &= ~((1ul << a_pgshift) - 1);
/*
* AVAL field 58..77 - base_page_shift bits of va
* we have space for 58..64 bits, Missing bits should
* be zero filled. +1 is to take care of L bit shift
*/
aval_shift = 64 - (77 - b_pgshift) + 1;
rb |= ((va_low << aval_shift) & 0xfe);
rb |= 1; /* L field */
rb |= r & 0xff000 & ((1ul << a_pgshift) - 1); /* LP field */
}
rb |= (v >> HPTE_V_SSIZE_SHIFT) << 8; /* B field */
return rb;
}
static inline unsigned long hpte_rpn(unsigned long ptel, unsigned long psize)
{
return ((ptel & HPTE_R_RPN) & ~(psize - 1)) >> PAGE_SHIFT;
}
static inline int hpte_is_writable(unsigned long ptel)
{
unsigned long pp = ptel & (HPTE_R_PP0 | HPTE_R_PP);
return pp != PP_RXRX && pp != PP_RXXX;
}
static inline unsigned long hpte_make_readonly(unsigned long ptel)
{
if ((ptel & HPTE_R_PP0) || (ptel & HPTE_R_PP) == PP_RWXX)
ptel = (ptel & ~HPTE_R_PP) | PP_RXXX;
else
ptel |= PP_RXRX;
return ptel;
}
static inline bool hpte_cache_flags_ok(unsigned long hptel, bool is_ci)
{
unsigned int wimg = hptel & HPTE_R_WIMG;
/* Handle SAO */
if (wimg == (HPTE_R_W | HPTE_R_I | HPTE_R_M) &&
cpu_has_feature(CPU_FTR_ARCH_206))
wimg = HPTE_R_M;
if (!is_ci)
return wimg == HPTE_R_M;
/*
* if host is mapped cache inhibited, make sure hptel also have
* cache inhibited.
*/
if (wimg & HPTE_R_W) /* FIXME!! is this ok for all guest. ? */
return false;
return !!(wimg & HPTE_R_I);
}
/*
* If it's present and writable, atomically set dirty and referenced bits and
* return the PTE, otherwise return 0.
*/
static inline pte_t kvmppc_read_update_linux_pte(pte_t *ptep, int writing)
{
pte_t old_pte, new_pte = __pte(0);
while (1) {
/*
* Make sure we don't reload from ptep
*/
old_pte = READ_ONCE(*ptep);
/*
* wait until H_PAGE_BUSY is clear then set it atomically
*/
if (unlikely(pte_val(old_pte) & H_PAGE_BUSY)) {
cpu_relax();
continue;
}
/* If pte is not present return None */
if (unlikely(!(pte_val(old_pte) & _PAGE_PRESENT)))
return __pte(0);
new_pte = pte_mkyoung(old_pte);
if (writing && pte_write(old_pte))
new_pte = pte_mkdirty(new_pte);
if (pte_xchg(ptep, old_pte, new_pte))
break;
}
return new_pte;
}
static inline bool hpte_read_permission(unsigned long pp, unsigned long key)
{
if (key)
return PP_RWRX <= pp && pp <= PP_RXRX;
return true;
}
static inline bool hpte_write_permission(unsigned long pp, unsigned long key)
{
if (key)
return pp == PP_RWRW;
return pp <= PP_RWRW;
}
static inline int hpte_get_skey_perm(unsigned long hpte_r, unsigned long amr)
{
unsigned long skey;
skey = ((hpte_r & HPTE_R_KEY_HI) >> 57) |
((hpte_r & HPTE_R_KEY_LO) >> 9);
return (amr >> (62 - 2 * skey)) & 3;
}
static inline void lock_rmap(unsigned long *rmap)
{
do {
while (test_bit(KVMPPC_RMAP_LOCK_BIT, rmap))
cpu_relax();
} while (test_and_set_bit_lock(KVMPPC_RMAP_LOCK_BIT, rmap));
}
static inline void unlock_rmap(unsigned long *rmap)
{
__clear_bit_unlock(KVMPPC_RMAP_LOCK_BIT, rmap);
}
static inline bool slot_is_aligned(struct kvm_memory_slot *memslot,
unsigned long pagesize)
{
unsigned long mask = (pagesize >> PAGE_SHIFT) - 1;
if (pagesize <= PAGE_SIZE)
return true;
return !(memslot->base_gfn & mask) && !(memslot->npages & mask);
}
/*
* This works for 4k, 64k and 16M pages on POWER7,
* and 4k and 16M pages on PPC970.
*/
static inline unsigned long slb_pgsize_encoding(unsigned long psize)
{
unsigned long senc = 0;
if (psize > 0x1000) {
senc = SLB_VSID_L;
if (psize == 0x10000)
senc |= SLB_VSID_LP_01;
}
return senc;
}
static inline int is_vrma_hpte(unsigned long hpte_v)
{
return (hpte_v & ~0xffffffUL) ==
(HPTE_V_1TB_SEG | (VRMA_VSID << (40 - 16)));
}
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
/*
* Note modification of an HPTE; set the HPTE modified bit
* if anyone is interested.
*/
static inline void note_hpte_modification(struct kvm *kvm,
struct revmap_entry *rev)
{
if (atomic_read(&kvm->arch.hpte_mod_interest))
rev->guest_rpte |= HPTE_GR_MODIFIED;
}
/*
* Like kvm_memslots(), but for use in real mode when we can't do
* any RCU stuff (since the secondary threads are offline from the
* kernel's point of view), and we can't print anything.
* Thus we use rcu_dereference_raw() rather than rcu_dereference_check().
*/
static inline struct kvm_memslots *kvm_memslots_raw(struct kvm *kvm)
{
return rcu_dereference_raw_notrace(kvm->memslots[0]);
}
extern void kvmppc_mmu_debugfs_init(struct kvm *kvm);
extern void kvmhv_rm_send_ipi(int cpu);
static inline unsigned long kvmppc_hpt_npte(struct kvm_hpt_info *hpt)
{
/* HPTEs are 2**4 bytes long */
return 1UL << (hpt->order - 4);
}
static inline unsigned long kvmppc_hpt_mask(struct kvm_hpt_info *hpt)
{
/* 128 (2**7) bytes in each HPTEG */
return (1UL << (hpt->order - 7)) - 1;
}
#endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */
#endif /* __ASM_KVM_BOOK3S_64_H__ */