-
Aneesh Kumar K.V authoredCurrently we limit the max addressable memory to 128TB. This patch increase the limit to 2PB. We can have devices like nvdimm which adds memory above 512TB limit. We still don't support regular system ram above 512TB. One of the challenge with that is the percpu allocator, that allocates per node memory and use the max distance between them as the percpu offsets. This means with large gap in address space ( system ram above 1PB) we will run out of vmalloc space to map the percpu allocation. In order to support addressable memory above 512TB, kernel should be able to linear map this range. To do that with hash translation we now add 4 context to kernel linear map region. Our per context addressable range is 512TB. We still keep VMALLOC and VMEMMAP region to old size. SLB miss handlers is updated to validate these limit. We also limit this update to SPARSEMEM_VMEMMAP and SPARSEMEM_EXTREME Signed-off-by:
Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>Aneesh Kumar K.V authoredCurrently we limit the max addressable memory to 128TB. This patch increase the limit to 2PB. We can have devices like nvdimm which adds memory above 512TB limit. We still don't support regular system ram above 512TB. One of the challenge with that is the percpu allocator, that allocates per node memory and use the max distance between them as the percpu offsets. This means with large gap in address space ( system ram above 1PB) we will run out of vmalloc space to map the percpu allocation. In order to support addressable memory above 512TB, kernel should be able to linear map this range. To do that with hash translation we now add 4 context to kernel linear map region. Our per context addressable range is 512TB. We still keep VMALLOC and VMEMMAP region to old size. SLB miss handlers is updated to validate these limit. We also limit this update to SPARSEMEM_VMEMMAP and SPARSEMEM_EXTREME Signed-off-by:
Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
mmu-hash.h 26.43 KiB
#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.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#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/bug.h>
#include <asm/processor.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_BIT0 ASM_CONST(0x2000000000000000)
#define HPTE_R_KEY_BIT1 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_BIT3 ASM_CONST(0x0000000000000400)
#define HPTE_R_KEY_BIT4 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 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
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);
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);
extern void slb_set_size(u16 size);
#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 (MAX_PHYSMEM_BITS > MAX_EA_BITS_PER_CONTEXT)
#define MAX_KERNEL_CTX_CNT (1UL << (MAX_PHYSMEM_BITS - MAX_EA_BITS_PER_CONTEXT))
#else
#define MAX_KERNEL_CTX_CNT 1
#endif
#define MAX_VMALLOC_CTX_CNT 1
#define MAX_MEMMAP_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.
*
* We add one extra context to MIN_USER_CONTEXT so that we can map kernel
* context easily. The +1 is to map the unused 0xe region mapping.
*/
#define MAX_USER_CONTEXT ((ASM_CONST(1) << CONTEXT_BITS) - 2)
#define MIN_USER_CONTEXT (MAX_KERNEL_CTX_CNT + MAX_VMALLOC_CTX_CNT + \
MAX_MEMMAP_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 TASK_SLICE_ARRAY_SZ(x) ((x)->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);
extern void subpage_prot_init_new_context(struct mm_struct *mm);
#else
static inline void subpage_prot_free(struct mm_struct *mm) {}
static inline void subpage_prot_init_new_context(struct mm_struct *mm) { }
#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 & ~REGION_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
* below. Range is 512TB per context.
*
* 0x00001 - [ 0xc000000000000000 - 0xc001ffffffffffff]
* 0x00002 - [ 0xc002000000000000 - 0xc003ffffffffffff]
* 0x00003 - [ 0xc004000000000000 - 0xc005ffffffffffff]
* 0x00004 - [ 0xc006000000000000 - 0xc007ffffffffffff]
* 0x00005 - [ 0xd000000000000000 - 0xd001ffffffffffff ]
* 0x00006 - Not used - Can map 0xe000000000000000 range.
* 0x00007 - [ 0xf000000000000000 - 0xf001ffffffffffff ]
*
* So we can compute the context from the region (top nibble) by * subtracting 11, or 0xc - 1.
*/
static inline unsigned long get_kernel_context(unsigned long ea)
{
unsigned long region_id = REGION_ID(ea);
unsigned long ctx;
/*
* For linear mapping we do support multiple context
*/
if (region_id == KERNEL_REGION_ID) {
/*
* We already verified ea to be not beyond the addr limit.
*/
ctx = 1 + ((ea & ~REGION_MASK) >> MAX_EA_BITS_PER_CONTEXT);
} else
ctx = (region_id - 0xc) + MAX_KERNEL_CTX_CNT;
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);
#endif /* __ASSEMBLY__ */
#endif /* _ASM_POWERPC_BOOK3S_64_MMU_HASH_H_ */