lkml.org 
[lkml]   [2019]   [Jul]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v9 04/21] mips: mm: Add p?d_leaf() definitions
Date
walk_page_range() is going to be allowed to walk page tables other than
those of user space. For this it needs to know when it has reached a
'leaf' entry in the page tables. This information is provided by the
p?d_leaf() functions/macros.

For mips, we only support large pages on 64 bit.

For 64 bit if _PAGE_HUGE is defined we can simply look for it. When not
defined we can be confident that there are no leaf pages in existence
and fall back on the generic implementation (added in a later patch)
which returns 0.

CC: Ralf Baechle <ralf@linux-mips.org>
CC: Paul Burton <paul.burton@mips.com>
CC: James Hogan <jhogan@kernel.org>
CC: linux-mips@vger.kernel.org
Signed-off-by: Steven Price <steven.price@arm.com>
---
arch/mips/include/asm/pgtable-64.h | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/arch/mips/include/asm/pgtable-64.h b/arch/mips/include/asm/pgtable-64.h
index 93a9dce31f25..2bdbf8652b5f 100644
--- a/arch/mips/include/asm/pgtable-64.h
+++ b/arch/mips/include/asm/pgtable-64.h
@@ -273,6 +273,10 @@ static inline int pmd_present(pmd_t pmd)
return pmd_val(pmd) != (unsigned long) invalid_pte_table;
}

+#ifdef _PAGE_HUGE
+#define pmd_leaf(pmd) ((pmd_val(pmd) & _PAGE_HUGE) != 0)
+#endif
+
static inline void pmd_clear(pmd_t *pmdp)
{
pmd_val(*pmdp) = ((unsigned long) invalid_pte_table);
@@ -297,6 +301,10 @@ static inline int pud_present(pud_t pud)
return pud_val(pud) != (unsigned long) invalid_pmd_table;
}

+#ifdef _PAGE_HUGE
+#define pud_leaf(pud) ((pud_val(pud) & _PAGE_HUGE) != 0)
+#endif
+
static inline void pud_clear(pud_t *pudp)
{
pud_val(*pudp) = ((unsigned long) invalid_pmd_table);
--
2.20.1
\
 
 \ /
  Last update: 2019-07-22 17:43    [W:0.340 / U:7.316 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site