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-rw-r--r-- | arch/powerpc/include/asm/book3s/64/mmu-hash.h | 885 |
1 files changed, 885 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/book3s/64/mmu-hash.h b/arch/powerpc/include/asm/book3s/64/mmu-hash.h new file mode 100644 index 000000000..1c4eebbc6 --- /dev/null +++ b/arch/powerpc/include/asm/book3s/64/mmu-hash.h @@ -0,0 +1,885 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef _ASM_POWERPC_BOOK3S_64_MMU_HASH_H_ +#define _ASM_POWERPC_BOOK3S_64_MMU_HASH_H_ +/* + * PowerPC64 memory management structures + * + * Dave Engebretsen & Mike Corrigan <{engebret|mikejc}@us.ibm.com> + * PPC64 rework. + */ + +#include <asm/page.h> +#include <asm/bug.h> +#include <asm/asm-const.h> + +/* + * This is necessary to get the definition of PGTABLE_RANGE which we + * need for various slices related matters. Note that this isn't the + * complete pgtable.h but only a portion of it. + */ +#include <asm/book3s/64/pgtable.h> +#include <asm/book3s/64/slice.h> +#include <asm/task_size_64.h> +#include <asm/cpu_has_feature.h> + +/* + * SLB + */ + +#define SLB_NUM_BOLTED 2 +#define SLB_CACHE_ENTRIES 8 +#define SLB_MIN_SIZE 32 + +/* Bits in the SLB ESID word */ +#define SLB_ESID_V ASM_CONST(0x0000000008000000) /* valid */ + +/* Bits in the SLB VSID word */ +#define SLB_VSID_SHIFT 12 +#define SLB_VSID_SHIFT_256M SLB_VSID_SHIFT +#define SLB_VSID_SHIFT_1T 24 +#define SLB_VSID_SSIZE_SHIFT 62 +#define SLB_VSID_B ASM_CONST(0xc000000000000000) +#define SLB_VSID_B_256M ASM_CONST(0x0000000000000000) +#define SLB_VSID_B_1T ASM_CONST(0x4000000000000000) +#define SLB_VSID_KS ASM_CONST(0x0000000000000800) +#define SLB_VSID_KP ASM_CONST(0x0000000000000400) +#define SLB_VSID_N ASM_CONST(0x0000000000000200) /* no-execute */ +#define SLB_VSID_L ASM_CONST(0x0000000000000100) +#define SLB_VSID_C ASM_CONST(0x0000000000000080) /* class */ +#define SLB_VSID_LP ASM_CONST(0x0000000000000030) +#define SLB_VSID_LP_00 ASM_CONST(0x0000000000000000) +#define SLB_VSID_LP_01 ASM_CONST(0x0000000000000010) +#define SLB_VSID_LP_10 ASM_CONST(0x0000000000000020) +#define SLB_VSID_LP_11 ASM_CONST(0x0000000000000030) +#define SLB_VSID_LLP (SLB_VSID_L|SLB_VSID_LP) + +#define SLB_VSID_KERNEL (SLB_VSID_KP) +#define SLB_VSID_USER (SLB_VSID_KP|SLB_VSID_KS|SLB_VSID_C) + +#define SLBIE_C (0x08000000) +#define SLBIE_SSIZE_SHIFT 25 + +/* + * Hash table + */ + +#define HPTES_PER_GROUP 8 + +#define HPTE_V_SSIZE_SHIFT 62 +#define HPTE_V_AVPN_SHIFT 7 +#define HPTE_V_COMMON_BITS ASM_CONST(0x000fffffffffffff) +#define HPTE_V_AVPN ASM_CONST(0x3fffffffffffff80) +#define HPTE_V_AVPN_3_0 ASM_CONST(0x000fffffffffff80) +#define HPTE_V_AVPN_VAL(x) (((x) & HPTE_V_AVPN) >> HPTE_V_AVPN_SHIFT) +#define HPTE_V_COMPARE(x,y) (!(((x) ^ (y)) & 0xffffffffffffff80UL)) +#define HPTE_V_BOLTED ASM_CONST(0x0000000000000010) +#define HPTE_V_LOCK ASM_CONST(0x0000000000000008) +#define HPTE_V_LARGE ASM_CONST(0x0000000000000004) +#define HPTE_V_SECONDARY ASM_CONST(0x0000000000000002) +#define HPTE_V_VALID ASM_CONST(0x0000000000000001) + +/* + * ISA 3.0 has a different HPTE format. + */ +#define HPTE_R_3_0_SSIZE_SHIFT 58 +#define HPTE_R_3_0_SSIZE_MASK (3ull << HPTE_R_3_0_SSIZE_SHIFT) +#define HPTE_R_PP0 ASM_CONST(0x8000000000000000) +#define HPTE_R_TS ASM_CONST(0x4000000000000000) +#define HPTE_R_KEY_HI ASM_CONST(0x3000000000000000) +#define HPTE_R_KEY_BIT4 ASM_CONST(0x2000000000000000) +#define HPTE_R_KEY_BIT3 ASM_CONST(0x1000000000000000) +#define HPTE_R_RPN_SHIFT 12 +#define HPTE_R_RPN ASM_CONST(0x0ffffffffffff000) +#define HPTE_R_RPN_3_0 ASM_CONST(0x01fffffffffff000) +#define HPTE_R_PP ASM_CONST(0x0000000000000003) +#define HPTE_R_PPP ASM_CONST(0x8000000000000003) +#define HPTE_R_N ASM_CONST(0x0000000000000004) +#define HPTE_R_G ASM_CONST(0x0000000000000008) +#define HPTE_R_M ASM_CONST(0x0000000000000010) +#define HPTE_R_I ASM_CONST(0x0000000000000020) +#define HPTE_R_W ASM_CONST(0x0000000000000040) +#define HPTE_R_WIMG ASM_CONST(0x0000000000000078) +#define HPTE_R_C ASM_CONST(0x0000000000000080) +#define HPTE_R_R ASM_CONST(0x0000000000000100) +#define HPTE_R_KEY_LO ASM_CONST(0x0000000000000e00) +#define HPTE_R_KEY_BIT2 ASM_CONST(0x0000000000000800) +#define HPTE_R_KEY_BIT1 ASM_CONST(0x0000000000000400) +#define HPTE_R_KEY_BIT0 ASM_CONST(0x0000000000000200) +#define HPTE_R_KEY (HPTE_R_KEY_LO | HPTE_R_KEY_HI) + +#define HPTE_V_1TB_SEG ASM_CONST(0x4000000000000000) +#define HPTE_V_VRMA_MASK ASM_CONST(0x4001ffffff000000) + +/* Values for PP (assumes Ks=0, Kp=1) */ +#define PP_RWXX 0 /* Supervisor read/write, User none */ +#define PP_RWRX 1 /* Supervisor read/write, User read */ +#define PP_RWRW 2 /* Supervisor read/write, User read/write */ +#define PP_RXRX 3 /* Supervisor read, User read */ +#define PP_RXXX (HPTE_R_PP0 | 2) /* Supervisor read, user none */ + +/* Fields for tlbiel instruction in architecture 2.06 */ +#define TLBIEL_INVAL_SEL_MASK 0xc00 /* invalidation selector */ +#define TLBIEL_INVAL_PAGE 0x000 /* invalidate a single page */ +#define TLBIEL_INVAL_SET_LPID 0x800 /* invalidate a set for current LPID */ +#define TLBIEL_INVAL_SET 0xc00 /* invalidate a set for all LPIDs */ +#define TLBIEL_INVAL_SET_MASK 0xfff000 /* set number to inval. */ +#define TLBIEL_INVAL_SET_SHIFT 12 + +#define POWER7_TLB_SETS 128 /* # sets in POWER7 TLB */ +#define POWER8_TLB_SETS 512 /* # sets in POWER8 TLB */ +#define POWER9_TLB_SETS_HASH 256 /* # sets in POWER9 TLB Hash mode */ +#define POWER9_TLB_SETS_RADIX 128 /* # sets in POWER9 TLB Radix mode */ + +#ifndef __ASSEMBLY__ + +struct mmu_hash_ops { + void (*hpte_invalidate)(unsigned long slot, + unsigned long vpn, + int bpsize, int apsize, + int ssize, int local); + long (*hpte_updatepp)(unsigned long slot, + unsigned long newpp, + unsigned long vpn, + int bpsize, int apsize, + int ssize, unsigned long flags); + void (*hpte_updateboltedpp)(unsigned long newpp, + unsigned long ea, + int psize, int ssize); + long (*hpte_insert)(unsigned long hpte_group, + unsigned long vpn, + unsigned long prpn, + unsigned long rflags, + unsigned long vflags, + int psize, int apsize, + int ssize); + long (*hpte_remove)(unsigned long hpte_group); + int (*hpte_removebolted)(unsigned long ea, + int psize, int ssize); + void (*flush_hash_range)(unsigned long number, int local); + void (*hugepage_invalidate)(unsigned long vsid, + unsigned long addr, + unsigned char *hpte_slot_array, + int psize, int ssize, int local); + int (*resize_hpt)(unsigned long shift); + /* + * Special for kexec. + * To be called in real mode with interrupts disabled. No locks are + * taken as such, concurrent access on pre POWER5 hardware could result + * in a deadlock. + * The linear mapping is destroyed as well. + */ + void (*hpte_clear_all)(void); +}; +extern struct mmu_hash_ops mmu_hash_ops; + +struct hash_pte { + __be64 v; + __be64 r; +}; + +extern struct hash_pte *htab_address; +extern unsigned long htab_size_bytes; +extern unsigned long htab_hash_mask; + + +static inline int shift_to_mmu_psize(unsigned int shift) +{ + int psize; + + for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) + if (mmu_psize_defs[psize].shift == shift) + return psize; + return -1; +} + +static inline unsigned int mmu_psize_to_shift(unsigned int mmu_psize) +{ + if (mmu_psize_defs[mmu_psize].shift) + return mmu_psize_defs[mmu_psize].shift; + BUG(); +} + +static inline unsigned int ap_to_shift(unsigned long ap) +{ + int psize; + + for (psize = 0; psize < MMU_PAGE_COUNT; psize++) { + if (mmu_psize_defs[psize].ap == ap) + return mmu_psize_defs[psize].shift; + } + + return -1; +} + +static inline unsigned long get_sllp_encoding(int psize) +{ + unsigned long sllp; + + sllp = ((mmu_psize_defs[psize].sllp & SLB_VSID_L) >> 6) | + ((mmu_psize_defs[psize].sllp & SLB_VSID_LP) >> 4); + return sllp; +} + +#endif /* __ASSEMBLY__ */ + +/* + * Segment sizes. + * These are the values used by hardware in the B field of + * SLB entries and the first dword of MMU hashtable entries. + * The B field is 2 bits; the values 2 and 3 are unused and reserved. + */ +#define MMU_SEGSIZE_256M 0 +#define MMU_SEGSIZE_1T 1 + +/* + * encode page number shift. + * in order to fit the 78 bit va in a 64 bit variable we shift the va by + * 12 bits. This enable us to address upto 76 bit va. + * For hpt hash from a va we can ignore the page size bits of va and for + * hpte encoding we ignore up to 23 bits of va. So ignoring lower 12 bits ensure + * we work in all cases including 4k page size. + */ +#define VPN_SHIFT 12 + +/* + * HPTE Large Page (LP) details + */ +#define LP_SHIFT 12 +#define LP_BITS 8 +#define LP_MASK(i) ((0xFF >> (i)) << LP_SHIFT) + +#ifndef __ASSEMBLY__ + +static inline int slb_vsid_shift(int ssize) +{ + if (ssize == MMU_SEGSIZE_256M) + return SLB_VSID_SHIFT; + return SLB_VSID_SHIFT_1T; +} + +static inline int segment_shift(int ssize) +{ + if (ssize == MMU_SEGSIZE_256M) + return SID_SHIFT; + return SID_SHIFT_1T; +} + +/* + * This array is indexed by the LP field of the HPTE second dword. + * Since this field may contain some RPN bits, some entries are + * replicated so that we get the same value irrespective of RPN. + * The top 4 bits are the page size index (MMU_PAGE_*) for the + * actual page size, the bottom 4 bits are the base page size. + */ +extern u8 hpte_page_sizes[1 << LP_BITS]; + +static inline unsigned long __hpte_page_size(unsigned long h, unsigned long l, + bool is_base_size) +{ + unsigned int i, lp; + + if (!(h & HPTE_V_LARGE)) + return 1ul << 12; + + /* Look at the 8 bit LP value */ + lp = (l >> LP_SHIFT) & ((1 << LP_BITS) - 1); + i = hpte_page_sizes[lp]; + if (!i) + return 0; + if (!is_base_size) + i >>= 4; + return 1ul << mmu_psize_defs[i & 0xf].shift; +} + +static inline unsigned long hpte_page_size(unsigned long h, unsigned long l) +{ + return __hpte_page_size(h, l, 0); +} + +static inline unsigned long hpte_base_page_size(unsigned long h, unsigned long l) +{ + return __hpte_page_size(h, l, 1); +} + +/* + * The current system page and segment sizes + */ +extern int mmu_kernel_ssize; +extern int mmu_highuser_ssize; +extern u16 mmu_slb_size; +extern unsigned long tce_alloc_start, tce_alloc_end; + +/* + * If the processor supports 64k normal pages but not 64k cache + * inhibited pages, we have to be prepared to switch processes + * to use 4k pages when they create cache-inhibited mappings. + * If this is the case, mmu_ci_restrictions will be set to 1. + */ +extern int mmu_ci_restrictions; + +/* + * This computes the AVPN and B fields of the first dword of a HPTE, + * for use when we want to match an existing PTE. The bottom 7 bits + * of the returned value are zero. + */ +static inline unsigned long hpte_encode_avpn(unsigned long vpn, int psize, + int ssize) +{ + unsigned long v; + /* + * The AVA field omits the low-order 23 bits of the 78 bits VA. + * These bits are not needed in the PTE, because the + * low-order b of these bits are part of the byte offset + * into the virtual page and, if b < 23, the high-order + * 23-b of these bits are always used in selecting the + * PTEGs to be searched + */ + v = (vpn >> (23 - VPN_SHIFT)) & ~(mmu_psize_defs[psize].avpnm); + v <<= HPTE_V_AVPN_SHIFT; + v |= ((unsigned long) ssize) << HPTE_V_SSIZE_SHIFT; + return v; +} + +/* + * ISA v3.0 defines a new HPTE format, which differs from the old + * format in having smaller AVPN and ARPN fields, and the B field + * in the second dword instead of the first. + */ +static inline unsigned long hpte_old_to_new_v(unsigned long v) +{ + /* trim AVPN, drop B */ + return v & HPTE_V_COMMON_BITS; +} + +static inline unsigned long hpte_old_to_new_r(unsigned long v, unsigned long r) +{ + /* move B field from 1st to 2nd dword, trim ARPN */ + return (r & ~HPTE_R_3_0_SSIZE_MASK) | + (((v) >> HPTE_V_SSIZE_SHIFT) << HPTE_R_3_0_SSIZE_SHIFT); +} + +static inline unsigned long hpte_new_to_old_v(unsigned long v, unsigned long r) +{ + /* insert B field */ + return (v & HPTE_V_COMMON_BITS) | + ((r & HPTE_R_3_0_SSIZE_MASK) << + (HPTE_V_SSIZE_SHIFT - HPTE_R_3_0_SSIZE_SHIFT)); +} + +static inline unsigned long hpte_new_to_old_r(unsigned long r) +{ + /* clear out B field */ + return r & ~HPTE_R_3_0_SSIZE_MASK; +} + +static inline unsigned long hpte_get_old_v(struct hash_pte *hptep) +{ + unsigned long hpte_v; + + hpte_v = be64_to_cpu(hptep->v); + if (cpu_has_feature(CPU_FTR_ARCH_300)) + hpte_v = hpte_new_to_old_v(hpte_v, be64_to_cpu(hptep->r)); + return hpte_v; +} + +/* + * This function sets the AVPN and L fields of the HPTE appropriately + * using the base page size and actual page size. + */ +static inline unsigned long hpte_encode_v(unsigned long vpn, int base_psize, + int actual_psize, int ssize) +{ + unsigned long v; + v = hpte_encode_avpn(vpn, base_psize, ssize); + if (actual_psize != MMU_PAGE_4K) + v |= HPTE_V_LARGE; + return v; +} + +/* + * This function sets the ARPN, and LP fields of the HPTE appropriately + * for the page size. We assume the pa is already "clean" that is properly + * aligned for the requested page size + */ +static inline unsigned long hpte_encode_r(unsigned long pa, int base_psize, + int actual_psize) +{ + /* A 4K page needs no special encoding */ + if (actual_psize == MMU_PAGE_4K) + return pa & HPTE_R_RPN; + else { + unsigned int penc = mmu_psize_defs[base_psize].penc[actual_psize]; + unsigned int shift = mmu_psize_defs[actual_psize].shift; + return (pa & ~((1ul << shift) - 1)) | (penc << LP_SHIFT); + } +} + +/* + * Build a VPN_SHIFT bit shifted va given VSID, EA and segment size. + */ +static inline unsigned long hpt_vpn(unsigned long ea, + unsigned long vsid, int ssize) +{ + unsigned long mask; + int s_shift = segment_shift(ssize); + + mask = (1ul << (s_shift - VPN_SHIFT)) - 1; + return (vsid << (s_shift - VPN_SHIFT)) | ((ea >> VPN_SHIFT) & mask); +} + +/* + * This hashes a virtual address + */ +static inline unsigned long hpt_hash(unsigned long vpn, + unsigned int shift, int ssize) +{ + unsigned long mask; + unsigned long hash, vsid; + + /* VPN_SHIFT can be atmost 12 */ + if (ssize == MMU_SEGSIZE_256M) { + mask = (1ul << (SID_SHIFT - VPN_SHIFT)) - 1; + hash = (vpn >> (SID_SHIFT - VPN_SHIFT)) ^ + ((vpn & mask) >> (shift - VPN_SHIFT)); + } else { + mask = (1ul << (SID_SHIFT_1T - VPN_SHIFT)) - 1; + vsid = vpn >> (SID_SHIFT_1T - VPN_SHIFT); + hash = vsid ^ (vsid << 25) ^ + ((vpn & mask) >> (shift - VPN_SHIFT)) ; + } + return hash & 0x7fffffffffUL; +} + +#define HPTE_LOCAL_UPDATE 0x1 +#define HPTE_NOHPTE_UPDATE 0x2 +#define HPTE_USE_KERNEL_KEY 0x4 + +long hpte_insert_repeating(unsigned long hash, unsigned long vpn, unsigned long pa, + unsigned long rlags, unsigned long vflags, int psize, int ssize); +extern int __hash_page_4K(unsigned long ea, unsigned long access, + unsigned long vsid, pte_t *ptep, unsigned long trap, + unsigned long flags, int ssize, int subpage_prot); +extern int __hash_page_64K(unsigned long ea, unsigned long access, + unsigned long vsid, pte_t *ptep, unsigned long trap, + unsigned long flags, int ssize); +struct mm_struct; +unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap); +extern int hash_page_mm(struct mm_struct *mm, unsigned long ea, + unsigned long access, unsigned long trap, + unsigned long flags); +extern int hash_page(unsigned long ea, unsigned long access, unsigned long trap, + unsigned long dsisr); +void low_hash_fault(struct pt_regs *regs, unsigned long address, int rc); +int __hash_page(unsigned long trap, unsigned long ea, unsigned long dsisr, unsigned long msr); +int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid, + pte_t *ptep, unsigned long trap, unsigned long flags, + int ssize, unsigned int shift, unsigned int mmu_psize); +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +extern int __hash_page_thp(unsigned long ea, unsigned long access, + unsigned long vsid, pmd_t *pmdp, unsigned long trap, + unsigned long flags, int ssize, unsigned int psize); +#else +static inline int __hash_page_thp(unsigned long ea, unsigned long access, + unsigned long vsid, pmd_t *pmdp, + unsigned long trap, unsigned long flags, + int ssize, unsigned int psize) +{ + BUG(); + return -1; +} +#endif +extern void hash_failure_debug(unsigned long ea, unsigned long access, + unsigned long vsid, unsigned long trap, + int ssize, int psize, int lpsize, + unsigned long pte); +extern int htab_bolt_mapping(unsigned long vstart, unsigned long vend, + unsigned long pstart, unsigned long prot, + int psize, int ssize); +int htab_remove_mapping(unsigned long vstart, unsigned long vend, + int psize, int ssize); +extern void pseries_add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages); +extern void demote_segment_4k(struct mm_struct *mm, unsigned long addr); + +extern void hash__setup_new_exec(void); + +#ifdef CONFIG_PPC_PSERIES +void hpte_init_pseries(void); +#else +static inline void hpte_init_pseries(void) { } +#endif + +extern void hpte_init_native(void); + +struct slb_entry { + u64 esid; + u64 vsid; +}; + +extern void slb_initialize(void); +void slb_flush_and_restore_bolted(void); +void slb_flush_all_realmode(void); +void __slb_restore_bolted_realmode(void); +void slb_restore_bolted_realmode(void); +void slb_save_contents(struct slb_entry *slb_ptr); +void slb_dump_contents(struct slb_entry *slb_ptr); + +extern void slb_vmalloc_update(void); +void preload_new_slb_context(unsigned long start, unsigned long sp); + +#ifdef CONFIG_PPC_64S_HASH_MMU +void slb_set_size(u16 size); +#else +static inline void slb_set_size(u16 size) { } +#endif + +#endif /* __ASSEMBLY__ */ + +/* + * VSID allocation (256MB segment) + * + * We first generate a 37-bit "proto-VSID". Proto-VSIDs are generated + * from mmu context id and effective segment id of the address. + * + * For user processes max context id is limited to MAX_USER_CONTEXT. + * more details in get_user_context + * + * For kernel space get_kernel_context + * + * The proto-VSIDs are then scrambled into real VSIDs with the + * multiplicative hash: + * + * VSID = (proto-VSID * VSID_MULTIPLIER) % VSID_MODULUS + * + * VSID_MULTIPLIER is prime, so in particular it is + * co-prime to VSID_MODULUS, making this a 1:1 scrambling function. + * Because the modulus is 2^n-1 we can compute it efficiently without + * a divide or extra multiply (see below). The scramble function gives + * robust scattering in the hash table (at least based on some initial + * results). + * + * We use VSID 0 to indicate an invalid VSID. The means we can't use context id + * 0, because a context id of 0 and an EA of 0 gives a proto-VSID of 0, which + * will produce a VSID of 0. + * + * We also need to avoid the last segment of the last context, because that + * would give a protovsid of 0x1fffffffff. That will result in a VSID 0 + * because of the modulo operation in vsid scramble. + */ + +/* + * Max Va bits we support as of now is 68 bits. We want 19 bit + * context ID. + * Restrictions: + * GPU has restrictions of not able to access beyond 128TB + * (47 bit effective address). We also cannot do more than 20bit PID. + * For p4 and p5 which can only do 65 bit VA, we restrict our CONTEXT_BITS + * to 16 bits (ie, we can only have 2^16 pids at the same time). + */ +#define VA_BITS 68 +#define CONTEXT_BITS 19 +#define ESID_BITS (VA_BITS - (SID_SHIFT + CONTEXT_BITS)) +#define ESID_BITS_1T (VA_BITS - (SID_SHIFT_1T + CONTEXT_BITS)) + +#define ESID_BITS_MASK ((1 << ESID_BITS) - 1) +#define ESID_BITS_1T_MASK ((1 << ESID_BITS_1T) - 1) + +/* + * Now certain config support MAX_PHYSMEM more than 512TB. Hence we will need + * to use more than one context for linear mapping the kernel. + * For vmalloc and memmap, we use just one context with 512TB. With 64 byte + * struct page size, we need ony 32 TB in memmap for 2PB (51 bits (MAX_PHYSMEM_BITS)). + */ +#if (H_MAX_PHYSMEM_BITS > MAX_EA_BITS_PER_CONTEXT) +#define MAX_KERNEL_CTX_CNT (1UL << (H_MAX_PHYSMEM_BITS - MAX_EA_BITS_PER_CONTEXT)) +#else +#define MAX_KERNEL_CTX_CNT 1 +#endif + +#define MAX_VMALLOC_CTX_CNT 1 +#define MAX_IO_CTX_CNT 1 +#define MAX_VMEMMAP_CTX_CNT 1 + +/* + * 256MB segment + * The proto-VSID space has 2^(CONTEX_BITS + ESID_BITS) - 1 segments + * available for user + kernel mapping. VSID 0 is reserved as invalid, contexts + * 1-4 are used for kernel mapping. Each segment contains 2^28 bytes. Each + * context maps 2^49 bytes (512TB). + * + * We also need to avoid the last segment of the last context, because that + * would give a protovsid of 0x1fffffffff. That will result in a VSID 0 + * because of the modulo operation in vsid scramble. + * + */ +#define MAX_USER_CONTEXT ((ASM_CONST(1) << CONTEXT_BITS) - 2) + +// The + 2 accounts for INVALID_REGION and 1 more to avoid overlap with kernel +#define MIN_USER_CONTEXT (MAX_KERNEL_CTX_CNT + MAX_VMALLOC_CTX_CNT + \ + MAX_IO_CTX_CNT + MAX_VMEMMAP_CTX_CNT + 2) + +/* + * For platforms that support on 65bit VA we limit the context bits + */ +#define MAX_USER_CONTEXT_65BIT_VA ((ASM_CONST(1) << (65 - (SID_SHIFT + ESID_BITS))) - 2) + +/* + * This should be computed such that protovosid * vsid_mulitplier + * doesn't overflow 64 bits. The vsid_mutliplier should also be + * co-prime to vsid_modulus. We also need to make sure that number + * of bits in multiplied result (dividend) is less than twice the number of + * protovsid bits for our modulus optmization to work. + * + * The below table shows the current values used. + * |-------+------------+----------------------+------------+-------------------| + * | | Prime Bits | proto VSID_BITS_65VA | Total Bits | 2* prot VSID_BITS | + * |-------+------------+----------------------+------------+-------------------| + * | 1T | 24 | 25 | 49 | 50 | + * |-------+------------+----------------------+------------+-------------------| + * | 256MB | 24 | 37 | 61 | 74 | + * |-------+------------+----------------------+------------+-------------------| + * + * |-------+------------+----------------------+------------+--------------------| + * | | Prime Bits | proto VSID_BITS_68VA | Total Bits | 2* proto VSID_BITS | + * |-------+------------+----------------------+------------+--------------------| + * | 1T | 24 | 28 | 52 | 56 | + * |-------+------------+----------------------+------------+--------------------| + * | 256MB | 24 | 40 | 64 | 80 | + * |-------+------------+----------------------+------------+--------------------| + * + */ +#define VSID_MULTIPLIER_256M ASM_CONST(12538073) /* 24-bit prime */ +#define VSID_BITS_256M (VA_BITS - SID_SHIFT) +#define VSID_BITS_65_256M (65 - SID_SHIFT) +/* + * Modular multiplicative inverse of VSID_MULTIPLIER under modulo VSID_MODULUS + */ +#define VSID_MULINV_256M ASM_CONST(665548017062) + +#define VSID_MULTIPLIER_1T ASM_CONST(12538073) /* 24-bit prime */ +#define VSID_BITS_1T (VA_BITS - SID_SHIFT_1T) +#define VSID_BITS_65_1T (65 - SID_SHIFT_1T) +#define VSID_MULINV_1T ASM_CONST(209034062) + +/* 1TB VSID reserved for VRMA */ +#define VRMA_VSID 0x1ffffffUL +#define USER_VSID_RANGE (1UL << (ESID_BITS + SID_SHIFT)) + +/* 4 bits per slice and we have one slice per 1TB */ +#define SLICE_ARRAY_SIZE (H_PGTABLE_RANGE >> 41) +#define LOW_SLICE_ARRAY_SZ (BITS_PER_LONG / BITS_PER_BYTE) +#define TASK_SLICE_ARRAY_SZ(x) ((x)->hash_context->slb_addr_limit >> 41) +#ifndef __ASSEMBLY__ + +#ifdef CONFIG_PPC_SUBPAGE_PROT +/* + * For the sub-page protection option, we extend the PGD with one of + * these. Basically we have a 3-level tree, with the top level being + * the protptrs array. To optimize speed and memory consumption when + * only addresses < 4GB are being protected, pointers to the first + * four pages of sub-page protection words are stored in the low_prot + * array. + * Each page of sub-page protection words protects 1GB (4 bytes + * protects 64k). For the 3-level tree, each page of pointers then + * protects 8TB. + */ +struct subpage_prot_table { + unsigned long maxaddr; /* only addresses < this are protected */ + unsigned int **protptrs[(TASK_SIZE_USER64 >> 43)]; + unsigned int *low_prot[4]; +}; + +#define SBP_L1_BITS (PAGE_SHIFT - 2) +#define SBP_L2_BITS (PAGE_SHIFT - 3) +#define SBP_L1_COUNT (1 << SBP_L1_BITS) +#define SBP_L2_COUNT (1 << SBP_L2_BITS) +#define SBP_L2_SHIFT (PAGE_SHIFT + SBP_L1_BITS) +#define SBP_L3_SHIFT (SBP_L2_SHIFT + SBP_L2_BITS) + +extern void subpage_prot_free(struct mm_struct *mm); +#else +static inline void subpage_prot_free(struct mm_struct *mm) {} +#endif /* CONFIG_PPC_SUBPAGE_PROT */ + +/* + * One bit per slice. We have lower slices which cover 256MB segments + * upto 4G range. That gets us 16 low slices. For the rest we track slices + * in 1TB size. + */ +struct slice_mask { + u64 low_slices; + DECLARE_BITMAP(high_slices, SLICE_NUM_HIGH); +}; + +struct hash_mm_context { + u16 user_psize; /* page size index */ + + /* SLB page size encodings*/ + unsigned char low_slices_psize[LOW_SLICE_ARRAY_SZ]; + unsigned char high_slices_psize[SLICE_ARRAY_SIZE]; + unsigned long slb_addr_limit; +#ifdef CONFIG_PPC_64K_PAGES + struct slice_mask mask_64k; +#endif + struct slice_mask mask_4k; +#ifdef CONFIG_HUGETLB_PAGE + struct slice_mask mask_16m; + struct slice_mask mask_16g; +#endif + +#ifdef CONFIG_PPC_SUBPAGE_PROT + struct subpage_prot_table *spt; +#endif /* CONFIG_PPC_SUBPAGE_PROT */ +}; + +#if 0 +/* + * The code below is equivalent to this function for arguments + * < 2^VSID_BITS, which is all this should ever be called + * with. However gcc is not clever enough to compute the + * modulus (2^n-1) without a second multiply. + */ +#define vsid_scramble(protovsid, size) \ + ((((protovsid) * VSID_MULTIPLIER_##size) % VSID_MODULUS_##size)) + +/* simplified form avoiding mod operation */ +#define vsid_scramble(protovsid, size) \ + ({ \ + unsigned long x; \ + x = (protovsid) * VSID_MULTIPLIER_##size; \ + x = (x >> VSID_BITS_##size) + (x & VSID_MODULUS_##size); \ + (x + ((x+1) >> VSID_BITS_##size)) & VSID_MODULUS_##size; \ + }) + +#else /* 1 */ +static inline unsigned long vsid_scramble(unsigned long protovsid, + unsigned long vsid_multiplier, int vsid_bits) +{ + unsigned long vsid; + unsigned long vsid_modulus = ((1UL << vsid_bits) - 1); + /* + * We have same multipler for both 256 and 1T segements now + */ + vsid = protovsid * vsid_multiplier; + vsid = (vsid >> vsid_bits) + (vsid & vsid_modulus); + return (vsid + ((vsid + 1) >> vsid_bits)) & vsid_modulus; +} + +#endif /* 1 */ + +/* Returns the segment size indicator for a user address */ +static inline int user_segment_size(unsigned long addr) +{ + /* Use 1T segments if possible for addresses >= 1T */ + if (addr >= (1UL << SID_SHIFT_1T)) + return mmu_highuser_ssize; + return MMU_SEGSIZE_256M; +} + +static inline unsigned long get_vsid(unsigned long context, unsigned long ea, + int ssize) +{ + unsigned long va_bits = VA_BITS; + unsigned long vsid_bits; + unsigned long protovsid; + + /* + * Bad address. We return VSID 0 for that + */ + if ((ea & EA_MASK) >= H_PGTABLE_RANGE) + return 0; + + if (!mmu_has_feature(MMU_FTR_68_BIT_VA)) + va_bits = 65; + + if (ssize == MMU_SEGSIZE_256M) { + vsid_bits = va_bits - SID_SHIFT; + protovsid = (context << ESID_BITS) | + ((ea >> SID_SHIFT) & ESID_BITS_MASK); + return vsid_scramble(protovsid, VSID_MULTIPLIER_256M, vsid_bits); + } + /* 1T segment */ + vsid_bits = va_bits - SID_SHIFT_1T; + protovsid = (context << ESID_BITS_1T) | + ((ea >> SID_SHIFT_1T) & ESID_BITS_1T_MASK); + return vsid_scramble(protovsid, VSID_MULTIPLIER_1T, vsid_bits); +} + +/* + * For kernel space, we use context ids as + * below. Range is 512TB per context. + * + * 0x00001 - [ 0xc000000000000000 - 0xc001ffffffffffff] + * 0x00002 - [ 0xc002000000000000 - 0xc003ffffffffffff] + * 0x00003 - [ 0xc004000000000000 - 0xc005ffffffffffff] + * 0x00004 - [ 0xc006000000000000 - 0xc007ffffffffffff] + * + * vmap, IO, vmemap + * + * 0x00005 - [ 0xc008000000000000 - 0xc009ffffffffffff] + * 0x00006 - [ 0xc00a000000000000 - 0xc00bffffffffffff] + * 0x00007 - [ 0xc00c000000000000 - 0xc00dffffffffffff] + * + */ +static inline unsigned long get_kernel_context(unsigned long ea) +{ + unsigned long region_id = get_region_id(ea); + unsigned long ctx; + /* + * Depending on Kernel config, kernel region can have one context + * or more. + */ + if (region_id == LINEAR_MAP_REGION_ID) { + /* + * We already verified ea to be not beyond the addr limit. + */ + ctx = 1 + ((ea & EA_MASK) >> MAX_EA_BITS_PER_CONTEXT); + } else + ctx = region_id + MAX_KERNEL_CTX_CNT - 1; + return ctx; +} + +/* + * This is only valid for addresses >= PAGE_OFFSET + */ +static inline unsigned long get_kernel_vsid(unsigned long ea, int ssize) +{ + unsigned long context; + + if (!is_kernel_addr(ea)) + return 0; + + context = get_kernel_context(ea); + return get_vsid(context, ea, ssize); +} + +unsigned htab_shift_for_mem_size(unsigned long mem_size); + +enum slb_index { + LINEAR_INDEX = 0, /* Kernel linear map (0xc000000000000000) */ + KSTACK_INDEX = 1, /* Kernel stack map */ +}; + +#define slb_esid_mask(ssize) \ + (((ssize) == MMU_SEGSIZE_256M) ? ESID_MASK : ESID_MASK_1T) + +static inline unsigned long mk_esid_data(unsigned long ea, int ssize, + enum slb_index index) +{ + return (ea & slb_esid_mask(ssize)) | SLB_ESID_V | index; +} + +static inline unsigned long __mk_vsid_data(unsigned long vsid, int ssize, + unsigned long flags) +{ + return (vsid << slb_vsid_shift(ssize)) | flags | + ((unsigned long)ssize << SLB_VSID_SSIZE_SHIFT); +} + +static inline unsigned long mk_vsid_data(unsigned long ea, int ssize, + unsigned long flags) +{ + return __mk_vsid_data(get_kernel_vsid(ea, ssize), ssize, flags); +} + +#endif /* __ASSEMBLY__ */ +#endif /* _ASM_POWERPC_BOOK3S_64_MMU_HASH_H_ */ |