lkml.org 
[lkml]   [2013]   [Aug]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Date
Subject[PATCH] tile: handle super huge pages in virt_to_pte
This tile-specific API had a minor bug, in that if a super huge (>4GB)
page mapped a particular address range, we wouldn't handle it correctly.
As part of fixing that bug, I also cleaned up some of the pud and pmd
accessors to make them more consistent.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
---
arch/tile/include/asm/pgtable_32.h | 2 ++
arch/tile/include/asm/pgtable_64.h | 24 +++++++++++++++++-------
arch/tile/mm/pgtable.c | 3 +++
3 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/arch/tile/include/asm/pgtable_32.h b/arch/tile/include/asm/pgtable_32.h
index 4ce4a7a..e5bdc0e 100644
--- a/arch/tile/include/asm/pgtable_32.h
+++ b/arch/tile/include/asm/pgtable_32.h
@@ -84,6 +84,8 @@ extern unsigned long VMALLOC_RESERVE /* = CONFIG_VMALLOC_RESERVE */;
/* We have no pmd or pud since we are strictly a two-level page table */
#include <asm-generic/pgtable-nopmd.h>

+static inline int pud_huge_page(pud_t pud) { return 0; }
+
/* We don't define any pgds for these addresses. */
static inline int pgd_addr_invalid(unsigned long addr)
{
diff --git a/arch/tile/include/asm/pgtable_64.h b/arch/tile/include/asm/pgtable_64.h
index 2492fa5..7cb8d35 100644
--- a/arch/tile/include/asm/pgtable_64.h
+++ b/arch/tile/include/asm/pgtable_64.h
@@ -63,6 +63,15 @@
/* We have no pud since we are a three-level page table. */
#include <asm-generic/pgtable-nopud.h>

+/*
+ * pmds are the same as pgds and ptes, so converting is a no-op.
+ */
+#define pmd_pte(pmd) (pmd)
+#define pmdp_ptep(pmdp) (pmdp)
+#define pte_pmd(pte) (pte)
+
+#define pud_pte(pud) ((pud).pgd)
+
static inline int pud_none(pud_t pud)
{
return pud_val(pud) == 0;
@@ -73,6 +82,11 @@ static inline int pud_present(pud_t pud)
return pud_val(pud) & _PAGE_PRESENT;
}

+static inline int pud_huge_page(pud_t pud)
+{
+ return pud_val(pud) & _PAGE_HUGE_PAGE;
+}
+
#define pmd_ERROR(e) \
pr_err("%s:%d: bad pmd 0x%016llx.\n", __FILE__, __LINE__, pmd_val(e))

@@ -89,6 +103,9 @@ static inline int pud_bad(pud_t pud)
/* Return the page-table frame number (ptfn) that a pud_t points at. */
#define pud_ptfn(pud) hv_pte_get_ptfn((pud).pgd)

+/* Return the page frame number (pfn) that a pud_t points at. */
+#define pud_pfn(pud) pte_pfn(pud_pte(pud))
+
/*
* A given kernel pud_t maps to a kernel pmd_t table at a specific
* virtual address. Since kernel pmd_t tables can be aligned at
@@ -152,13 +169,6 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
return hv_pte(__insn_exch(&ptep->val, 0UL));
}

-/*
- * pmds are the same as pgds and ptes, so converting is a no-op.
- */
-#define pmd_pte(pmd) (pmd)
-#define pmdp_ptep(pmdp) (pmdp)
-#define pte_pmd(pte) (pte)
-
#endif /* __ASSEMBLY__ */

#endif /* _ASM_TILE_PGTABLE_64_H */
diff --git a/arch/tile/mm/pgtable.c b/arch/tile/mm/pgtable.c
index e41487e..3004433 100644
--- a/arch/tile/mm/pgtable.c
+++ b/arch/tile/mm/pgtable.c
@@ -338,6 +338,8 @@ pte_t *virt_to_pte(struct mm_struct* mm, unsigned long addr)
pud = pud_offset(pgd, addr);
if (!pud_present(*pud))
return NULL;
+ if (pud_huge_page(*pud))
+ return (pte_t *)pud;
pmd = pmd_offset(pud, addr);
if (pmd_huge_page(*pmd))
return (pte_t *)pmd;
@@ -345,6 +347,7 @@ pte_t *virt_to_pte(struct mm_struct* mm, unsigned long addr)
return NULL;
return pte_offset_kernel(pmd, addr);
}
+EXPORT_SYMBOL(virt_to_pte);

pgprot_t set_remote_cache_cpu(pgprot_t prot, int cpu)
{
--
1.8.3.1


\
 
 \ /
  Last update: 2013-08-12 18:41    [W:0.025 / U:0.060 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site