Documented the return values of KVA mapping functions,
pud_set_huge(), pmd_set_huge, pud_clear_huge() and
pmd_clear_huge().
Simplified the conditions to select HAVE_ARCH_HUGE_VMAP
in Kconfig since X86_PAE depends on X86_32.
There is no functinal change in this patch.
Signed-off-by: Toshi Kani <toshi.k...@hp.com>
---
arch/x86/Kconfig | 2 +-
arch/x86/mm/pgtable.c | 36 ++++++++++++++++++++++++++++--------
2 files changed, 29 insertions(+), 9 deletions(-)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 110f6ae..ba5e78e 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -99,7 +99,7 @@ config X86
select IRQ_FORCED_THREADING
select HAVE_BPF_JIT if X86_64
select HAVE_ARCH_TRANSPARENT_HUGEPAGE
- select HAVE_ARCH_HUGE_VMAP if X86_64 || (X86_32 && X86_PAE)
+ select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
select ARCH_HAS_SG_CHAIN
select CLKEVT_I8253
select ARCH_HAVE_NMI_SAFE_CMPXCHG
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index 0b97d2c..a0f7eeb 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -563,14 +563,19 @@ void native_set_fixmap(enum fixed_addresses idx,
phys_addr_t phys,
}
#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
+/**
+ * pud_set_huge - setup kernel PUD mapping
+ *
+ * MTRRs can override PAT memory types with a 4KB granularity. Therefore,
+ * it does not set up a huge page when the range is covered by non-WB type
+ * of MTRRs. 0xFF indicates that MTRRs are disabled.
+ *
+ * Return 1 on success, and 0 on no-operation.
+ */
int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot)
{
u8 mtrr;
- /*
- * Do not use a huge page when the range is covered by non-WB type
- * of MTRRs.
- */
mtrr = mtrr_type_lookup(addr, addr + PUD_SIZE);
if ((mtrr != MTRR_TYPE_WRBACK) && (mtrr != 0xFF))
return 0;
@@ -584,14 +589,19 @@ int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t
prot)
return 1;
}
+/**
+ * pmd_set_huge - setup kernel PMD mapping
+ *
+ * MTRRs can override PAT memory types with a 4KB granularity. Therefore,
+ * it does not set up a huge page when the range is covered by non-WB type
+ * of MTRRs. 0xFF indicates that MTRRs are disabled.
+ *
+ * Return 1 on success, and 0 on no-operation.
+ */
int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot)
{
u8 mtrr;
- /*
- * Do not use a huge page when the range is covered by non-WB type
- * of MTRRs.
- */
mtrr = mtrr_type_lookup(addr, addr + PMD_SIZE);
if ((mtrr != MTRR_TYPE_WRBACK) && (mtrr != 0xFF))
return 0;
@@ -605,6 +615,11 @@ int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t
prot)
return 1;
}
+/**
+ * pud_clear_huge - clear kernel PUD mapping when it is set
+ *
+ * Return 1 on success, and 0 on no-operation.
+ */
int pud_clear_huge(pud_t *pud)
{
if (pud_large(*pud)) {
@@ -615,6 +630,11 @@ int pud_clear_huge(pud_t *pud)
return 0;
}
+/**
+ * pmd_clear_huge - clear kernel PMD mapping when it is set
+ *
+ * Return 1 on success, and 0 on no-operation.
+ */
int pmd_clear_huge(pmd_t *pmd)
{
if (pmd_large(*pmd)) {
--
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