[PATCH -tip 1/2] x86: PAT cleanup req_type special case for pat reserve_memtype

[PATCH -tip 1/2] x86: PAT cleanup req_type special case for pat reserve_memtype

[Xiaotian Feng]

commit b6ff32 consolidates code in pat_x_mtrr_type and reserve_memtype,
which removes the special case (req_type is -1) for pat enabled part.
We should also change comments and pat disabled part.

Signed-off-by: Xiaotian Feng <dfeng@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> 
---
 arch/x86/mm/pat.c |    7 +------
 1 files changed, 1 insertions(+), 6 deletions(-)

diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index e78cd0e..81fb753 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -355,9 +355,6 @@ static int free_ram_pages_type(u64 start, u64 end)
  * - _PAGE_CACHE_UC_MINUS
  * - _PAGE_CACHE_UC
  *
- * req_type will have a special case value '-1', when requester want to inherit
- * the memory type from mtrr (if WB), existing PAT, defaulting to UC_MINUS.
- *
  * If new_type is NULL, function will return an error if it cannot reserve the
  * region with req_type. If new_type is non-NULL, function will return
  * available type in new_type in case of no error. In case of any error
@@ -377,9 +374,7 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
 	if (!pat_enabled) {
 		/* This is identical to page table setting without PAT */
 		if (new_type) {
-			if (req_type == -1)
-				*new_type = _PAGE_CACHE_WB;
-			else if (req_type == _PAGE_CACHE_WC)
+			if (req_type == _PAGE_CACHE_WC)
 				*new_type = _PAGE_CACHE_UC_MINUS;
 			else
 				*new_type = req_type & _PAGE_CACHE_MASK;
-- 
1.6.2.5

[tip:x86/pat] x86: pat: Clean up req_type special case for reserve_memtype()

[tip-bot for Xiaotian Feng]

Commit-ID:  83ea05ea69290b2e30da795527dbe304db1e2331
Gitweb:     http://git.kernel.org/tip/83ea05ea69290b2e30da795527dbe304db1e2331
Author:     Xiaotian Feng <dfeng@redhat.com>
AuthorDate: Tue, 10 Nov 2009 17:23:07 +0800
Committer:  Ingo Molnar <mingo@elte.hu>
CommitDate: Tue, 10 Nov 2009 10:34:04 +0100

x86: pat: Clean up req_type special case for reserve_memtype()

Commit:

  b6ff32d: x86, PAT: Consolidate code in pat_x_mtrr_type() and reserve_memtype()

consolidated code in pat_x_mtrr_type() and reserve_memtype(),
which removed the special case (req_type is -1) for the
PAT-enabled part.

We should also change comments and the PAT-disabled part.

Signed-off-by: Xiaotian Feng <dfeng@redhat.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
LKML-Reference: <1257844987-7906-1-git-send-email-dfeng@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 arch/x86/mm/pat.c |    7 +------
 1 files changed, 1 insertions(+), 6 deletions(-)

diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index e78cd0e..81fb753 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -355,9 +355,6 @@ static int free_ram_pages_type(u64 start, u64 end)
  * - _PAGE_CACHE_UC_MINUS
  * - _PAGE_CACHE_UC
  *
- * req_type will have a special case value '-1', when requester want to inherit
- * the memory type from mtrr (if WB), existing PAT, defaulting to UC_MINUS.
- *
  * If new_type is NULL, function will return an error if it cannot reserve the
  * region with req_type. If new_type is non-NULL, function will return
  * available type in new_type in case of no error. In case of any error
@@ -377,9 +374,7 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
 	if (!pat_enabled) {
 		/* This is identical to page table setting without PAT */
 		if (new_type) {
-			if (req_type == -1)
-				*new_type = _PAGE_CACHE_WB;
-			else if (req_type == _PAGE_CACHE_WC)
+			if (req_type == _PAGE_CACHE_WC)
 				*new_type = _PAGE_CACHE_UC_MINUS;
 			else
 				*new_type = req_type & _PAGE_CACHE_MASK;