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>
diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h b/arch/powerpc/include/asm/kvm_book3s_64.h
index d55c7f8..b21936c 100644
--- a/arch/powerpc/include/asm/kvm_book3s_64.h
+++ b/arch/powerpc/include/asm/kvm_book3s_64.h
@@ -107,18 +107,96 @@ static inline void __unlock_hpte(__be64 *hpte, unsigned long hpte_v)
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 i, b_psize = MMU_PAGE_4K, a_psize = MMU_PAGE_4K;
- unsigned int penc;
+ int a_pgshift, b_pgshift;
unsigned long rb = 0, va_low, sllp;
- unsigned int lp = (r >> LP_SHIFT) & ((1 << LP_BITS) - 1);
- if (v & HPTE_V_LARGE) {
- i = hpte_page_sizes[lp];
- b_psize = i & 0xf;
- a_psize = i >> 4;
+ b_pgshift = a_pgshift = kvmppc_hpte_page_shifts(v, r);
+ if (a_pgshift >= 0x100) {
+ b_pgshift &= 0xff;
+ a_pgshift >>= 8;
}
/*
@@ -152,37 +230,33 @@ static inline unsigned long compute_tlbie_rb(unsigned long v, unsigned long r,
va_low ^= v >> (SID_SHIFT_1T - 16);
va_low &= 0x7ff;
- switch (b_psize) {
- case MMU_PAGE_4K:
- sllp = get_sllp_encoding(a_psize);
- rb |= sllp << 5; /* AP field */
+ 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 */
- break;
- default:
- {
+ } else {
int aval_shift;
/*
* remaining bits of AVA/LP fields
* Also contain the rr bits of LP
*/
- rb |= (va_low << mmu_psize_defs[b_psize].shift) & 0x7ff000;
+ rb |= (va_low << b_pgshift) & 0x7ff000;
/*
* Now clear not needed LP bits based on actual psize
*/
- rb &= ~((1ul << mmu_psize_defs[a_psize].shift) - 1);
+ 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 - mmu_psize_defs[b_psize].shift) + 1;
+ aval_shift = 64 - (77 - b_pgshift) + 1;
rb |= ((va_low << aval_shift) & 0xfe);
rb |= 1; /* L field */
- penc = mmu_psize_defs[b_psize].penc[a_psize];
- rb |= penc << 12; /* LP field */
- break;
- }
+ rb |= r & 0xff000 & ((1ul << a_pgshift) - 1); /* LP field */
}
rb |= (v >> HPTE_V_SSIZE_SHIFT) << 8; /* B field */
return rb;