[PATCH 4/4] x86/mm: Unexport __cachemode2pte_tbl

From: Christoph Hellwig
Date: Wed Apr 08 2020 - 11:28:03 EST


Exporting the raw data for a table is generally a bad idea. Move
cachemode2protval out of line given that it isn't really used in the
fast path, and then mark __cachemode2pte_tbl static.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
arch/x86/include/asm/pgtable_types.h | 14 ++------------
arch/x86/mm/init.c | 11 +++++++++--
arch/x86/mm/pat/set_memory.c | 5 +++++
3 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h
index a3b78d84b26a..567abdbd64d3 100644
--- a/arch/x86/include/asm/pgtable_types.h
+++ b/arch/x86/include/asm/pgtable_types.h
@@ -467,8 +467,6 @@ static inline pteval_t pte_flags(pte_t pte)
return native_pte_val(pte) & PTE_FLAGS_MASK;
}

-extern uint16_t __cachemode2pte_tbl[_PAGE_CACHE_MODE_NUM];
-
#define __pte2cm_idx(cb) \
((((cb) >> (_PAGE_BIT_PAT - 2)) & 4) | \
(((cb) >> (_PAGE_BIT_PCD - 1)) & 2) | \
@@ -478,16 +476,8 @@ extern uint16_t __cachemode2pte_tbl[_PAGE_CACHE_MODE_NUM];
(((i) & 2) << (_PAGE_BIT_PCD - 1)) | \
(((i) & 1) << _PAGE_BIT_PWT))

-static inline unsigned long cachemode2protval(enum page_cache_mode pcm)
-{
- if (likely(pcm == 0))
- return 0;
- return __cachemode2pte_tbl[pcm];
-}
-static inline pgprot_t cachemode2pgprot(enum page_cache_mode pcm)
-{
- return __pgprot(cachemode2protval(pcm));
-}
+unsigned long cachemode2protval(enum page_cache_mode pcm);
+
static inline unsigned long protval_4k_2_large(unsigned long val)
{
return (val & ~(_PAGE_PAT | _PAGE_PAT_LARGE)) |
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index 8482ee51b225..4a8d0d67e729 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -49,7 +49,7 @@
* Index into __pte2cachemode_tbl[] are the caching attribute bits of the pte
* (_PAGE_PWT, _PAGE_PCD, _PAGE_PAT) at index bit positions 0, 1, 2.
*/
-uint16_t __cachemode2pte_tbl[_PAGE_CACHE_MODE_NUM] = {
+static uint16_t __cachemode2pte_tbl[_PAGE_CACHE_MODE_NUM] = {
[_PAGE_CACHE_MODE_WB ] = 0 | 0 ,
[_PAGE_CACHE_MODE_WC ] = 0 | _PAGE_PCD,
[_PAGE_CACHE_MODE_UC_MINUS] = 0 | _PAGE_PCD,
@@ -57,7 +57,14 @@ uint16_t __cachemode2pte_tbl[_PAGE_CACHE_MODE_NUM] = {
[_PAGE_CACHE_MODE_WT ] = 0 | _PAGE_PCD,
[_PAGE_CACHE_MODE_WP ] = 0 | _PAGE_PCD,
};
-EXPORT_SYMBOL(__cachemode2pte_tbl);
+
+unsigned long cachemode2protval(enum page_cache_mode pcm)
+{
+ if (likely(pcm == 0))
+ return 0;
+ return __cachemode2pte_tbl[pcm];
+}
+EXPORT_SYMBOL(cachemode2protval);

static uint8_t __pte2cachemode_tbl[8] = {
[__pte2cm_idx( 0 | 0 | 0 )] = _PAGE_CACHE_MODE_WB,
diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
index 6d5424069e2b..b8ee3f4e8202 100644
--- a/arch/x86/mm/pat/set_memory.c
+++ b/arch/x86/mm/pat/set_memory.c
@@ -68,6 +68,11 @@ static DEFINE_SPINLOCK(cpa_lock);
#define CPA_PAGES_ARRAY 4
#define CPA_NO_CHECK_ALIAS 8 /* Do not search for aliases */

+static inline pgprot_t cachemode2pgprot(enum page_cache_mode pcm)
+{
+ return __pgprot(cachemode2protval(pcm));
+}
+
#ifdef CONFIG_PROC_FS
static unsigned long direct_pages_count[PG_LEVEL_NUM];

--
2.25.1