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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/x86/include/asm/pgtable-3level.h
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/include/asm/pgtable-3level.h')
-rw-r--r--arch/x86/include/asm/pgtable-3level.h209
1 files changed, 209 insertions, 0 deletions
diff --git a/arch/x86/include/asm/pgtable-3level.h b/arch/x86/include/asm/pgtable-3level.h
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+++ b/arch/x86/include/asm/pgtable-3level.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_PGTABLE_3LEVEL_H
+#define _ASM_X86_PGTABLE_3LEVEL_H
+
+/*
+ * Intel Physical Address Extension (PAE) Mode - three-level page
+ * tables on PPro+ CPUs.
+ *
+ * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
+ */
+
+#define pte_ERROR(e) \
+ pr_err("%s:%d: bad pte %p(%08lx%08lx)\n", \
+ __FILE__, __LINE__, &(e), (e).pte_high, (e).pte_low)
+#define pmd_ERROR(e) \
+ pr_err("%s:%d: bad pmd %p(%016Lx)\n", \
+ __FILE__, __LINE__, &(e), pmd_val(e))
+#define pgd_ERROR(e) \
+ pr_err("%s:%d: bad pgd %p(%016Lx)\n", \
+ __FILE__, __LINE__, &(e), pgd_val(e))
+
+#define pxx_xchg64(_pxx, _ptr, _val) ({ \
+ _pxx##val_t *_p = (_pxx##val_t *)_ptr; \
+ _pxx##val_t _o = *_p; \
+ do { } while (!try_cmpxchg64(_p, &_o, (_val))); \
+ native_make_##_pxx(_o); \
+})
+
+/*
+ * Rules for using set_pte: the pte being assigned *must* be
+ * either not present or in a state where the hardware will
+ * not attempt to update the pte. In places where this is
+ * not possible, use pte_get_and_clear to obtain the old pte
+ * value and then use set_pte to update it. -ben
+ */
+static inline void native_set_pte(pte_t *ptep, pte_t pte)
+{
+ WRITE_ONCE(ptep->pte_high, pte.pte_high);
+ smp_wmb();
+ WRITE_ONCE(ptep->pte_low, pte.pte_low);
+}
+
+static inline void native_set_pte_atomic(pte_t *ptep, pte_t pte)
+{
+ pxx_xchg64(pte, ptep, native_pte_val(pte));
+}
+
+static inline void native_set_pmd(pmd_t *pmdp, pmd_t pmd)
+{
+ pxx_xchg64(pmd, pmdp, native_pmd_val(pmd));
+}
+
+static inline void native_set_pud(pud_t *pudp, pud_t pud)
+{
+#ifdef CONFIG_PAGE_TABLE_ISOLATION
+ pud.p4d.pgd = pti_set_user_pgtbl(&pudp->p4d.pgd, pud.p4d.pgd);
+#endif
+ pxx_xchg64(pud, pudp, native_pud_val(pud));
+}
+
+/*
+ * For PTEs and PDEs, we must clear the P-bit first when clearing a page table
+ * entry, so clear the bottom half first and enforce ordering with a compiler
+ * barrier.
+ */
+static inline void native_pte_clear(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep)
+{
+ WRITE_ONCE(ptep->pte_low, 0);
+ smp_wmb();
+ WRITE_ONCE(ptep->pte_high, 0);
+}
+
+static inline void native_pmd_clear(pmd_t *pmdp)
+{
+ WRITE_ONCE(pmdp->pmd_low, 0);
+ smp_wmb();
+ WRITE_ONCE(pmdp->pmd_high, 0);
+}
+
+static inline void native_pud_clear(pud_t *pudp)
+{
+}
+
+static inline void pud_clear(pud_t *pudp)
+{
+ set_pud(pudp, __pud(0));
+
+ /*
+ * According to Intel App note "TLBs, Paging-Structure Caches,
+ * and Their Invalidation", April 2007, document 317080-001,
+ * section 8.1: in PAE mode we explicitly have to flush the
+ * TLB via cr3 if the top-level pgd is changed...
+ *
+ * Currently all places where pud_clear() is called either have
+ * flush_tlb_mm() followed or don't need TLB flush (x86_64 code or
+ * pud_clear_bad()), so we don't need TLB flush here.
+ */
+}
+
+
+#ifdef CONFIG_SMP
+static inline pte_t native_ptep_get_and_clear(pte_t *ptep)
+{
+ return pxx_xchg64(pte, ptep, 0ULL);
+}
+
+static inline pmd_t native_pmdp_get_and_clear(pmd_t *pmdp)
+{
+ return pxx_xchg64(pmd, pmdp, 0ULL);
+}
+
+static inline pud_t native_pudp_get_and_clear(pud_t *pudp)
+{
+ return pxx_xchg64(pud, pudp, 0ULL);
+}
+#else
+#define native_ptep_get_and_clear(xp) native_local_ptep_get_and_clear(xp)
+#define native_pmdp_get_and_clear(xp) native_local_pmdp_get_and_clear(xp)
+#define native_pudp_get_and_clear(xp) native_local_pudp_get_and_clear(xp)
+#endif
+
+#ifndef pmdp_establish
+#define pmdp_establish pmdp_establish
+static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
+ unsigned long address, pmd_t *pmdp, pmd_t pmd)
+{
+ pmd_t old;
+
+ /*
+ * If pmd has present bit cleared we can get away without expensive
+ * cmpxchg64: we can update pmdp half-by-half without racing with
+ * anybody.
+ */
+ if (!(pmd_val(pmd) & _PAGE_PRESENT)) {
+ /* xchg acts as a barrier before setting of the high bits */
+ old.pmd_low = xchg(&pmdp->pmd_low, pmd.pmd_low);
+ old.pmd_high = READ_ONCE(pmdp->pmd_high);
+ WRITE_ONCE(pmdp->pmd_high, pmd.pmd_high);
+
+ return old;
+ }
+
+ return pxx_xchg64(pmd, pmdp, pmd.pmd);
+}
+#endif
+
+/*
+ * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
+ * are !pte_none() && !pte_present().
+ *
+ * Format of swap PTEs:
+ *
+ * 6 6 6 6 5 5 5 5 5 5 5 5 5 5 4 4 4 4 4 4 4 4 4 4 3 3 3 3 3 3 3 3
+ * 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2
+ * < type -> <---------------------- offset ----------------------
+ *
+ * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
+ * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
+ * --------------------------------------------> 0 E 0 0 0 0 0 0 0
+ *
+ * E is the exclusive marker that is not stored in swap entries.
+ */
+#define SWP_TYPE_BITS 5
+#define _SWP_TYPE_MASK ((1U << SWP_TYPE_BITS) - 1)
+
+#define SWP_OFFSET_FIRST_BIT (_PAGE_BIT_PROTNONE + 1)
+
+/* We always extract/encode the offset by shifting it all the way up, and then down again */
+#define SWP_OFFSET_SHIFT (SWP_OFFSET_FIRST_BIT + SWP_TYPE_BITS)
+
+#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > SWP_TYPE_BITS)
+#define __swp_type(x) (((x).val) & _SWP_TYPE_MASK)
+#define __swp_offset(x) ((x).val >> SWP_TYPE_BITS)
+#define __swp_entry(type, offset) ((swp_entry_t){((type) & _SWP_TYPE_MASK) \
+ | (offset) << SWP_TYPE_BITS})
+
+/*
+ * Normally, __swp_entry() converts from arch-independent swp_entry_t to
+ * arch-dependent swp_entry_t, and __swp_entry_to_pte() just stores the result
+ * to pte. But here we have 32bit swp_entry_t and 64bit pte, and need to use the
+ * whole 64 bits. Thus, we shift the "real" arch-dependent conversion to
+ * __swp_entry_to_pte() through the following helper macro based on 64bit
+ * __swp_entry().
+ */
+#define __swp_pteval_entry(type, offset) ((pteval_t) { \
+ (~(pteval_t)(offset) << SWP_OFFSET_SHIFT >> SWP_TYPE_BITS) \
+ | ((pteval_t)(type) << (64 - SWP_TYPE_BITS)) })
+
+#define __swp_entry_to_pte(x) ((pte_t){ .pte = \
+ __swp_pteval_entry(__swp_type(x), __swp_offset(x)) })
+/*
+ * Analogically, __pte_to_swp_entry() doesn't just extract the arch-dependent
+ * swp_entry_t, but also has to convert it from 64bit to the 32bit
+ * intermediate representation, using the following macros based on 64bit
+ * __swp_type() and __swp_offset().
+ */
+#define __pteval_swp_type(x) ((unsigned long)((x).pte >> (64 - SWP_TYPE_BITS)))
+#define __pteval_swp_offset(x) ((unsigned long)(~((x).pte) << SWP_TYPE_BITS >> SWP_OFFSET_SHIFT))
+
+#define __pte_to_swp_entry(pte) (__swp_entry(__pteval_swp_type(pte), \
+ __pteval_swp_offset(pte)))
+
+/* We borrow bit 7 to store the exclusive marker in swap PTEs. */
+#define _PAGE_SWP_EXCLUSIVE _PAGE_PSE
+
+#include <asm/pgtable-invert.h>
+
+#endif /* _ASM_X86_PGTABLE_3LEVEL_H */