void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte);
void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte);
-static inline void native_pte_clear(struct mm_struct *mm, unsigned long addr,
- pte_t *ptep)
+static inline void native_set_pte(pte_t *ptep, pte_t pte)
{
- *ptep = native_make_pte(0);
+ WRITE_ONCE(*ptep, pte);
}
-static inline void native_set_pte(pte_t *ptep, pte_t pte)
+static inline void native_pte_clear(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep)
{
- *ptep = pte;
+ native_set_pte(ptep, native_make_pte(0));
}
static inline void native_set_pte_atomic(pte_t *ptep, pte_t pte)
static inline void native_set_pmd(pmd_t *pmdp, pmd_t pmd)
{
- *pmdp = pmd;
+ WRITE_ONCE(*pmdp, pmd);
}
static inline void native_pmd_clear(pmd_t *pmd)
static inline void native_set_pud(pud_t *pudp, pud_t pud)
{
- *pudp = pud;
+ WRITE_ONCE(*pudp, pud);
}
static inline void native_pud_clear(pud_t *pud)
#endif
}
-#ifdef CONFIG_PAGE_TABLE_ISOLATION
-/*
- * All top-level PAGE_TABLE_ISOLATION page tables are order-1 pages
- * (8k-aligned and 8k in size). The kernel one is at the beginning 4k and
- * the user one is in the last 4k. To switch between them, you
- * just need to flip the 12th bit in their addresses.
- */
-#define PTI_PGTABLE_SWITCH_BIT PAGE_SHIFT
-
-/*
- * This generates better code than the inline assembly in
- * __set_bit().
- */
-static inline void *ptr_set_bit(void *ptr, int bit)
-{
- unsigned long __ptr = (unsigned long)ptr;
-
- __ptr |= BIT(bit);
- return (void *)__ptr;
-}
-static inline void *ptr_clear_bit(void *ptr, int bit)
-{
- unsigned long __ptr = (unsigned long)ptr;
-
- __ptr &= ~BIT(bit);
- return (void *)__ptr;
-}
-
-static inline pgd_t *kernel_to_user_pgdp(pgd_t *pgdp)
-{
- return ptr_set_bit(pgdp, PTI_PGTABLE_SWITCH_BIT);
-}
-
-static inline pgd_t *user_to_kernel_pgdp(pgd_t *pgdp)
-{
- return ptr_clear_bit(pgdp, PTI_PGTABLE_SWITCH_BIT);
-}
-
-static inline p4d_t *kernel_to_user_p4dp(p4d_t *p4dp)
-{
- return ptr_set_bit(p4dp, PTI_PGTABLE_SWITCH_BIT);
-}
-
-static inline p4d_t *user_to_kernel_p4dp(p4d_t *p4dp)
-{
- return ptr_clear_bit(p4dp, PTI_PGTABLE_SWITCH_BIT);
-}
-#endif /* CONFIG_PAGE_TABLE_ISOLATION */
-
-/*
- * Page table pages are page-aligned. The lower half of the top
- * level is used for userspace and the top half for the kernel.
- *
- * Returns true for parts of the PGD that map userspace and
- * false for the parts that map the kernel.
- */
-static inline bool pgdp_maps_userspace(void *__ptr)
-{
- unsigned long ptr = (unsigned long)__ptr;
-
- return (ptr & ~PAGE_MASK) < (PAGE_SIZE / 2);
-}
-
-#ifdef CONFIG_PAGE_TABLE_ISOLATION
-pgd_t __pti_set_user_pgd(pgd_t *pgdp, pgd_t pgd);
-
-/*
- * Take a PGD location (pgdp) and a pgd value that needs to be set there.
- * Populates the user and returns the resulting PGD that must be set in
- * the kernel copy of the page tables.
- */
-static inline pgd_t pti_set_user_pgd(pgd_t *pgdp, pgd_t pgd)
-{
- if (!static_cpu_has(X86_FEATURE_PTI))
- return pgd;
- return __pti_set_user_pgd(pgdp, pgd);
-}
-#else
-static inline pgd_t pti_set_user_pgd(pgd_t *pgdp, pgd_t pgd)
-{
- return pgd;
-}
-#endif
-
static inline void native_set_p4d(p4d_t *p4dp, p4d_t p4d)
{
pgd_t pgd;
if (pgtable_l5_enabled() || !IS_ENABLED(CONFIG_PAGE_TABLE_ISOLATION)) {
- *p4dp = p4d;
+ WRITE_ONCE(*p4dp, p4d);
return;
}
pgd = native_make_pgd(native_p4d_val(p4d));
- pgd = pti_set_user_pgd((pgd_t *)p4dp, pgd);
- *p4dp = native_make_p4d(native_pgd_val(pgd));
+ pgd = pti_set_user_pgtbl((pgd_t *)p4dp, pgd);
+ WRITE_ONCE(*p4dp, native_make_p4d(native_pgd_val(pgd)));
}
static inline void native_p4d_clear(p4d_t *p4d)
static inline void native_set_pgd(pgd_t *pgdp, pgd_t pgd)
{
- *pgdp = pti_set_user_pgd(pgdp, pgd);
+ WRITE_ONCE(*pgdp, pti_set_user_pgtbl(pgdp, pgd));
}
static inline void native_pgd_clear(pgd_t *pgd)
/*
* Level 4 access.
*/
-static inline int pgd_large(pgd_t pgd) { return 0; }
#define mk_kernel_pgd(address) __pgd((address) | _KERNPG_TABLE)
/* PUD - Level3 access */
*
* | ... | 11| 10| 9|8|7|6|5| 4| 3|2| 1|0| <- bit number
* | ... |SW3|SW2|SW1|G|L|D|A|CD|WT|U| W|P| <- bit names
- * | OFFSET (14->63) | TYPE (9-13) |0|0|X|X| X| X|X|SD|0| <- swp entry
+ * | TYPE (59-63) | ~OFFSET (9-58) |0|0|X|X| X| X|X|SD|0| <- swp entry
*
* G (8) is aliased and used as a PROT_NONE indicator for
* !present ptes. We need to start storing swap entries above
*
* Bit 7 in swp entry should be 0 because pmd_present checks not only P,
* but also L and G.
+ *
+ * The offset is inverted by a binary not operation to make the high
+ * physical bits set.
*/
-#define SWP_TYPE_FIRST_BIT (_PAGE_BIT_PROTNONE + 1)
-#define SWP_TYPE_BITS 5
-/* Place the offset above the type: */
-#define SWP_OFFSET_FIRST_BIT (SWP_TYPE_FIRST_BIT + SWP_TYPE_BITS)
+#define SWP_TYPE_BITS 5
+
+#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_FIRST_BIT)) \
- & ((1U << SWP_TYPE_BITS) - 1))
-#define __swp_offset(x) ((x).val >> SWP_OFFSET_FIRST_BIT)
-#define __swp_entry(type, offset) ((swp_entry_t) { \
- ((type) << (SWP_TYPE_FIRST_BIT)) \
- | ((offset) << SWP_OFFSET_FIRST_BIT) })
+/* Extract the high bits for type */
+#define __swp_type(x) ((x).val >> (64 - SWP_TYPE_BITS))
+
+/* Shift up (to get rid of type), then down to get value */
+#define __swp_offset(x) (~(x).val << SWP_TYPE_BITS >> SWP_OFFSET_SHIFT)
+
+/*
+ * Shift the offset up "too far" by TYPE bits, then down again
+ * The offset is inverted by a binary not operation to make the high
+ * physical bits set.
+ */
+#define __swp_entry(type, offset) ((swp_entry_t) { \
+ (~(unsigned long)(offset) << SWP_OFFSET_SHIFT >> SWP_TYPE_BITS) \
+ | ((unsigned long)(type) << (64-SWP_TYPE_BITS)) })
+
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val((pte)) })
#define __pmd_to_swp_entry(pmd) ((swp_entry_t) { pmd_val((pmd)) })
#define __swp_entry_to_pte(x) ((pte_t) { .pte = (x).val })
return true;
}
+#include <asm/pgtable-invert.h>
+
#endif /* !__ASSEMBLY__ */
#endif /* _ASM_X86_PGTABLE_64_H */
projects / linux-2.6-microblaze.git / blobdiff