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Diffstat (limited to 'arch/powerpc/include/asm/book3s/64/hash-64k.h')
-rw-r--r--arch/powerpc/include/asm/book3s/64/hash-64k.h163
1 files changed, 118 insertions, 45 deletions
diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h
index 9732837aaae8..7deb3a66890b 100644
--- a/arch/powerpc/include/asm/book3s/64/hash-64k.h
+++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h
@@ -1,10 +1,43 @@
+/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_POWERPC_BOOK3S_64_HASH_64K_H
#define _ASM_POWERPC_BOOK3S_64_HASH_64K_H
-#define H_PTE_INDEX_SIZE 8
-#define H_PMD_INDEX_SIZE 10
-#define H_PUD_INDEX_SIZE 7
-#define H_PGD_INDEX_SIZE 8
+#define H_PTE_INDEX_SIZE 8 // size: 8B << 8 = 2KB, maps 2^8 x 64KB = 16MB
+#define H_PMD_INDEX_SIZE 10 // size: 8B << 10 = 8KB, maps 2^10 x 16MB = 16GB
+#define H_PUD_INDEX_SIZE 10 // size: 8B << 10 = 8KB, maps 2^10 x 16GB = 16TB
+#define H_PGD_INDEX_SIZE 8 // size: 8B << 8 = 2KB, maps 2^8 x 16TB = 4PB
+
+/*
+ * If we store section details in page->flags we can't increase the MAX_PHYSMEM_BITS
+ * if we increase SECTIONS_WIDTH we will not store node details in page->flags and
+ * page_to_nid does a page->section->node lookup
+ * Hence only increase for VMEMMAP. Further depending on SPARSEMEM_EXTREME reduce
+ * memory requirements with large number of sections.
+ * 51 bits is the max physical real address on POWER9
+ */
+#if defined(CONFIG_SPARSEMEM_VMEMMAP) && defined(CONFIG_SPARSEMEM_EXTREME)
+#define H_MAX_PHYSMEM_BITS 51
+#else
+#define H_MAX_PHYSMEM_BITS 46
+#endif
+
+/*
+ * Each context is 512TB size. SLB miss for first context/default context
+ * is handled in the hotpath.
+ */
+#define MAX_EA_BITS_PER_CONTEXT 49
+#define REGION_SHIFT MAX_EA_BITS_PER_CONTEXT
+
+/*
+ * We use one context for each MAP area.
+ */
+#define H_KERN_MAP_SIZE (1UL << MAX_EA_BITS_PER_CONTEXT)
+
+/*
+ * Define the address range of the kernel non-linear virtual area
+ * 2PB
+ */
+#define H_KERN_VIRT_START ASM_CONST(0xc008000000000000)
/*
* 64k aligned address free up few of the lower bits of RPN for us
@@ -12,33 +45,41 @@
*/
#define H_PAGE_COMBO _RPAGE_RPN0 /* this is a combo 4k page */
#define H_PAGE_4K_PFN _RPAGE_RPN1 /* PFN is for a single 4k page */
+#define H_PAGE_BUSY _RPAGE_RSV1 /* software: PTE & hash are busy */
+#define H_PAGE_HASHPTE _RPAGE_RPN43 /* PTE has associated HPTE */
+
+/* memory key bits. */
+#define H_PTE_PKEY_BIT4 _RPAGE_PKEY_BIT4
+#define H_PTE_PKEY_BIT3 _RPAGE_PKEY_BIT3
+#define H_PTE_PKEY_BIT2 _RPAGE_PKEY_BIT2
+#define H_PTE_PKEY_BIT1 _RPAGE_PKEY_BIT1
+#define H_PTE_PKEY_BIT0 _RPAGE_PKEY_BIT0
+
/*
* We need to differentiate between explicit huge page and THP huge
* page, since THP huge page also need to track real subpage details
*/
#define H_PAGE_THP_HUGE H_PAGE_4K_PFN
-/*
- * Used to track subpage group valid if H_PAGE_COMBO is set
- * This overloads H_PAGE_F_GIX and H_PAGE_F_SECOND
- */
-#define H_PAGE_COMBO_VALID (H_PAGE_F_GIX | H_PAGE_F_SECOND)
-
/* PTE flags to conserve for HPTE identification */
-#define _PAGE_HPTEFLAGS (H_PAGE_BUSY | H_PAGE_F_SECOND | \
- H_PAGE_F_GIX | H_PAGE_HASHPTE | H_PAGE_COMBO)
-/*
- * we support 16 fragments per PTE page of 64K size.
- */
-#define H_PTE_FRAG_NR 16
+#define _PAGE_HPTEFLAGS (H_PAGE_BUSY | H_PAGE_HASHPTE | H_PAGE_COMBO)
/*
* We use a 2K PTE page fragment and another 2K for storing
* real_pte_t hash index
+ * 8 bytes per each pte entry and another 8 bytes for storing
+ * slot details.
*/
-#define H_PTE_FRAG_SIZE_SHIFT 12
-#define PTE_FRAG_SIZE (1UL << PTE_FRAG_SIZE_SHIFT)
+#define H_PTE_FRAG_SIZE_SHIFT (H_PTE_INDEX_SIZE + 3 + 1)
+#define H_PTE_FRAG_NR (PAGE_SIZE >> H_PTE_FRAG_SIZE_SHIFT)
+
+#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLB_PAGE)
+#define H_PMD_FRAG_SIZE_SHIFT (H_PMD_INDEX_SIZE + 3 + 1)
+#else
+#define H_PMD_FRAG_SIZE_SHIFT (H_PMD_INDEX_SIZE + 3)
+#endif
+#define H_PMD_FRAG_NR (PAGE_SIZE >> H_PMD_FRAG_SIZE_SHIFT)
-#ifndef __ASSEMBLY__
+#ifndef __ASSEMBLER__
#include <asm/errno.h>
/*
@@ -48,30 +89,64 @@
* generic accessors and iterators here
*/
#define __real_pte __real_pte
-static inline real_pte_t __real_pte(pte_t pte, pte_t *ptep)
+static inline real_pte_t __real_pte(pte_t pte, pte_t *ptep, int offset)
{
real_pte_t rpte;
unsigned long *hidxp;
rpte.pte = pte;
- rpte.hidx = 0;
- if (pte_val(pte) & H_PAGE_COMBO) {
- /*
- * Make sure we order the hidx load against the H_PAGE_COMBO
- * check. The store side ordering is done in __hash_page_4K
- */
- smp_rmb();
- hidxp = (unsigned long *)(ptep + PTRS_PER_PTE);
- rpte.hidx = *hidxp;
- }
+
+ /*
+ * Ensure that we do not read the hidx before we read the PTE. Because
+ * the writer side is expected to finish writing the hidx first followed
+ * by the PTE, by using smp_wmb(). pte_set_hash_slot() ensures that.
+ */
+ smp_rmb();
+
+ hidxp = (unsigned long *)(ptep + offset);
+ rpte.hidx = *hidxp;
return rpte;
}
+/*
+ * shift the hidx representation by one-modulo-0xf; i.e hidx 0 is respresented
+ * as 1, 1 as 2,... , and 0xf as 0. This convention lets us represent a
+ * invalid hidx 0xf with a 0x0 bit value. PTEs are anyway zero'd when
+ * allocated. We dont have to zero them gain; thus save on the initialization.
+ */
+#define HIDX_UNSHIFT_BY_ONE(x) ((x + 0xfUL) & 0xfUL) /* shift backward by one */
+#define HIDX_SHIFT_BY_ONE(x) ((x + 0x1UL) & 0xfUL) /* shift forward by one */
+#define HIDX_BITS(x, index) (x << (index << 2))
+#define BITS_TO_HIDX(x, index) ((x >> (index << 2)) & 0xfUL)
+#define INVALID_RPTE_HIDX 0x0UL
+
static inline unsigned long __rpte_to_hidx(real_pte_t rpte, unsigned long index)
{
- if ((pte_val(rpte.pte) & H_PAGE_COMBO))
- return (rpte.hidx >> (index<<2)) & 0xf;
- return (pte_val(rpte.pte) >> H_PAGE_F_GIX_SHIFT) & 0xf;
+ return HIDX_UNSHIFT_BY_ONE(BITS_TO_HIDX(rpte.hidx, index));
+}
+
+/*
+ * Commit the hidx and return PTE bits that needs to be modified. The caller is
+ * expected to modify the PTE bits accordingly and commit the PTE to memory.
+ */
+static inline unsigned long pte_set_hidx(pte_t *ptep, real_pte_t rpte,
+ unsigned int subpg_index,
+ unsigned long hidx, int offset)
+{
+ unsigned long *hidxp = (unsigned long *)(ptep + offset);
+
+ rpte.hidx &= ~HIDX_BITS(0xfUL, subpg_index);
+ *hidxp = rpte.hidx | HIDX_BITS(HIDX_SHIFT_BY_ONE(hidx), subpg_index);
+
+ /*
+ * Anyone reading PTE must ensure hidx bits are read after reading the
+ * PTE by using the read-side barrier smp_rmb(). __real_pte() can be
+ * used for that.
+ */
+ smp_wmb();
+
+ /* No PTE bits to be modified, return 0x0UL */
+ return 0x0UL;
}
#define __rpte_to_pte(r) ((r).pte)
@@ -88,10 +163,9 @@ extern bool __rpte_sub_valid(real_pte_t rpte, unsigned long index);
shift = mmu_psize_defs[psize].shift; \
for (index = 0; vpn < __end; index++, \
vpn += (1L << (shift - VPN_SHIFT))) { \
- if (!__split || __rpte_sub_valid(rpte, index)) \
- do {
+ if (!__split || __rpte_sub_valid(rpte, index))
-#define pte_iterate_hashed_end() } while(0); } } while(0)
+#define pte_iterate_hashed_end() } } while(0)
#define pte_pagesize_index(mm, addr, pte) \
(((pte) & H_PAGE_COMBO)? MMU_PAGE_4K: MMU_PAGE_64K)
@@ -110,13 +184,18 @@ static inline int hash__remap_4k_pfn(struct vm_area_struct *vma, unsigned long a
}
#define H_PTE_TABLE_SIZE PTE_FRAG_SIZE
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined (CONFIG_HUGETLB_PAGE)
#define H_PMD_TABLE_SIZE ((sizeof(pmd_t) << PMD_INDEX_SIZE) + \
(sizeof(unsigned long) << PMD_INDEX_SIZE))
#else
#define H_PMD_TABLE_SIZE (sizeof(pmd_t) << PMD_INDEX_SIZE)
#endif
+#ifdef CONFIG_HUGETLB_PAGE
+#define H_PUD_TABLE_SIZE ((sizeof(pud_t) << PUD_INDEX_SIZE) + \
+ (sizeof(unsigned long) << PUD_INDEX_SIZE))
+#else
#define H_PUD_TABLE_SIZE (sizeof(pud_t) << PUD_INDEX_SIZE)
+#endif
#define H_PGD_TABLE_SIZE (sizeof(pgd_t) << PGD_INDEX_SIZE)
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
@@ -184,11 +263,6 @@ static inline int hash__pmd_trans_huge(pmd_t pmd)
(_PAGE_PTE | H_PAGE_THP_HUGE));
}
-static inline int hash__pmd_same(pmd_t pmd_a, pmd_t pmd_b)
-{
- return (((pmd_raw(pmd_a) ^ pmd_raw(pmd_b)) & ~cpu_to_be64(_PAGE_HPTEFLAGS)) == 0);
-}
-
static inline pmd_t hash__pmd_mkhuge(pmd_t pmd)
{
return __pmd(pmd_val(pmd) | (_PAGE_PTE | H_PAGE_THP_HUGE));
@@ -202,12 +276,11 @@ extern pmd_t hash__pmdp_collapse_flush(struct vm_area_struct *vma,
extern void hash__pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
pgtable_t pgtable);
extern pgtable_t hash__pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp);
-extern void hash__pmdp_huge_split_prepare(struct vm_area_struct *vma,
- unsigned long address, pmd_t *pmdp);
extern pmd_t hash__pmdp_huge_get_and_clear(struct mm_struct *mm,
unsigned long addr, pmd_t *pmdp);
extern int hash__has_transparent_hugepage(void);
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
-#endif /* __ASSEMBLY__ */
+
+#endif /* __ASSEMBLER__ */
#endif /* _ASM_POWERPC_BOOK3S_64_HASH_64K_H */
generated by cgit (git 2.34.1) at 2025-12-29 12:10:13 +0000