[PATCH 0/5] x86/boot: Some string function cleanup and consolidation

[PATCH 0/5] x86/boot: Some string function cleanup and consolidation

[Vivek Goyal]

Hi Peter,

I have tried cleaning up a bit the usage of string functions in arch/x86/boot/.

I have created x86/boot/string.h which all the callers can include and by
default they get the built in definition of memcpy, memset and memcmp. Those
who want to use optimized version of these functions, need to #undef respective
macro and link again the approprate string.c file which provides the function
definition.

After this change I am planning to include x86/boot/string.h in purgatory
code and get built-in definitions of memcpy, memset and memcmp.

There seem to be lot of magic going on in arch/x86/boot/. I do not claim
to understand it all. Hopefully above changes do not break anything.

Please have a look.

Thanks
Vivek


Vivek Goyal (5):
  x86/boot: undef memcmp before providing a new definition
  x86/boot: Create a separate string.h file to provide standard string
    functions
  x86/boot: Move optmized memcpy() 32/64 bit versions to
    compressed/string.c
  x86/boot: Move memcmp() into string.h and string.c
  x86/boot: Move memset() definition in compressed/string.c

 arch/x86/boot/boot.h              | 13 ----------
 arch/x86/boot/compressed/misc.c   | 51 ++++++---------------------------------
 arch/x86/boot/compressed/string.c | 46 ++++++++++++++++++++++++++++++-----
 arch/x86/boot/cpucheck.c          |  1 +
 arch/x86/boot/edd.c               |  1 +
 arch/x86/boot/main.c              |  1 +
 arch/x86/boot/regs.c              |  1 +
 arch/x86/boot/string.c            | 14 +++++++++++
 arch/x86/boot/string.h            | 21 ++++++++++++++++
 arch/x86/boot/video-vesa.c        |  1 +
 10 files changed, 88 insertions(+), 62 deletions(-)
 create mode 100644 arch/x86/boot/string.h

-- 
1.8.5.3

[PATCH 1/5] x86/boot: undef memcmp before providing a new definition

[Vivek Goyal]

With CONFIG_X86_32=y, string_32.h gets pulled in compressed/string.c by
"misch.h". string_32.h defines a macro to map memcmp to __builtin_memcmp().
And that macro in turn changes the name of memcmp() defined here and
converts it to __builtin_memcmp().

I thought that's not the intention though. We probably want to provide
our own optimized definition of memcmp(). If yes, then undef the memcmp
before we define a new memcmp.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 arch/x86/boot/compressed/string.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/boot/compressed/string.c b/arch/x86/boot/compressed/string.c
index ffb9c5c..212004e 100644
--- a/arch/x86/boot/compressed/string.c
+++ b/arch/x86/boot/compressed/string.c
@@ -1,5 +1,7 @@
 #include "misc.h"
 
+/* Avoid intereference from any defines in string_32.h */
+#undef memcmp
 int memcmp(const void *s1, const void *s2, size_t len)
 {
 	u8 diff;
-- 
1.8.5.3

[PATCH 2/5] x86/boot: Create a separate string.h file to provide standard string functions

[Vivek Goyal]

Create a separate arch/x86/boot/string.h file to provide declaration of
some of the common string functions.

By default memcpy, memset and memcmp functions will default to gcc
builtin functions. If code wants to use an optimized version of any
of these functions, they need to #undef the respective macro and link
against a local file providing definition of undefed function.

For example, arch/x86/boot/* code links against copy.S to get memcpy()
and memcmp() definitions. arch/86/boot/compressed/* links against
compressed/string.c.

There are quite a few places in arch/x86/ where these functions are
used. Idea is to try to consilidate  their declaration and possibly
definitions so that it can be reused.

I am planning to reuse boot/string.h in arch/x86/purgatory/ and use
gcc builtin functions for memcpy, memset and memcmp.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 arch/x86/boot/boot.h       |  5 -----
 arch/x86/boot/cpucheck.c   |  1 +
 arch/x86/boot/edd.c        |  1 +
 arch/x86/boot/main.c       |  1 +
 arch/x86/boot/regs.c       |  1 +
 arch/x86/boot/string.h     | 19 +++++++++++++++++++
 arch/x86/boot/video-vesa.c |  1 +
 7 files changed, 24 insertions(+), 5 deletions(-)
 create mode 100644 arch/x86/boot/string.h

diff --git a/arch/x86/boot/boot.h b/arch/x86/boot/boot.h
index 50f8c5e..bed9665 100644
--- a/arch/x86/boot/boot.h
+++ b/arch/x86/boot/boot.h
@@ -228,11 +228,6 @@ void copy_to_fs(addr_t dst, void *src, size_t len);
 void *copy_from_fs(void *dst, addr_t src, size_t len);
 void copy_to_gs(addr_t dst, void *src, size_t len);
 void *copy_from_gs(void *dst, addr_t src, size_t len);
-void *memcpy(void *dst, void *src, size_t len);
-void *memset(void *dst, int c, size_t len);
-
-#define memcpy(d,s,l) __builtin_memcpy(d,s,l)
-#define memset(d,c,l) __builtin_memset(d,c,l)
 
 /* a20.c */
 int enable_a20(void);
diff --git a/arch/x86/boot/cpucheck.c b/arch/x86/boot/cpucheck.c
index 100a9a1..086c4f4 100644
--- a/arch/x86/boot/cpucheck.c
+++ b/arch/x86/boot/cpucheck.c
@@ -27,6 +27,7 @@
 #include <asm/processor-flags.h>
 #include <asm/required-features.h>
 #include <asm/msr-index.h>
+#include "string.h"
 
 static u32 err_flags[NCAPINTS];
 
diff --git a/arch/x86/boot/edd.c b/arch/x86/boot/edd.c
index c501a5b..223e425 100644
--- a/arch/x86/boot/edd.c
+++ b/arch/x86/boot/edd.c
@@ -15,6 +15,7 @@
 
 #include "boot.h"
 #include <linux/edd.h>
+#include "string.h"
 
 #if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
 
diff --git a/arch/x86/boot/main.c b/arch/x86/boot/main.c
index cf6083d..fd6c9f2 100644
--- a/arch/x86/boot/main.c
+++ b/arch/x86/boot/main.c
@@ -14,6 +14,7 @@
  */
 
 #include "boot.h"
+#include "string.h"
 
 struct boot_params boot_params __attribute__((aligned(16)));
 
diff --git a/arch/x86/boot/regs.c b/arch/x86/boot/regs.c
index 958019b..c0fb356 100644
--- a/arch/x86/boot/regs.c
+++ b/arch/x86/boot/regs.c
@@ -17,6 +17,7 @@
  */
 
 #include "boot.h"
+#include "string.h"
 
 void initregs(struct biosregs *reg)
 {
diff --git a/arch/x86/boot/string.h b/arch/x86/boot/string.h
new file mode 100644
index 0000000..10939d8
--- /dev/null
+++ b/arch/x86/boot/string.h
@@ -0,0 +1,19 @@
+#ifndef BOOT_STRING_H
+#define BOOT_STRING_H
+
+/* Undef any of these macros coming from string_32.h. */
+#undef memcpy
+#undef memset
+#undef memcmp
+
+void *memcpy(void *dst, const void *src, size_t len);
+void *memset(void *dst, int c, size_t len);
+
+/*
+ * Access builtin version by default. If one needs to use optimized version,
+ * do "undef memcpy" in .c file and link against right string.c
+ */
+#define memcpy(d,s,l) __builtin_memcpy(d,s,l)
+#define memset(d,c,l) __builtin_memset(d,c,l)
+
+#endif /* BOOT_STRING_H */
diff --git a/arch/x86/boot/video-vesa.c b/arch/x86/boot/video-vesa.c
index 11e8c6e..ba3e100 100644
--- a/arch/x86/boot/video-vesa.c
+++ b/arch/x86/boot/video-vesa.c
@@ -16,6 +16,7 @@
 #include "boot.h"
 #include "video.h"
 #include "vesa.h"
+#include "string.h"
 
 /* VESA information */
 static struct vesa_general_info vginfo;
-- 
1.8.5.3

[PATCH 3/5] x86/boot: Move optmized memcpy() 32/64 bit versions to compressed/string.c

[Vivek Goyal]

Move optimzied versions of memcpy to compressed/string.c This will allow
any other code to use these functions too if need be in future. Again
trying to put definition in a common place instead of hiding it in misc.c

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 arch/x86/boot/compressed/misc.c   | 31 +------------------------------
 arch/x86/boot/compressed/string.c | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+), 30 deletions(-)

diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index 196eaf3..3100092 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -10,6 +10,7 @@
  */
 
 #include "misc.h"
+#include "../string.h"
 
 /* WARNING!!
  * This code is compiled with -fPIC and it is relocated dynamically
@@ -110,7 +111,6 @@ static void error(char *m);
 struct boot_params *real_mode;		/* Pointer to real-mode data */
 
 void *memset(void *s, int c, size_t n);
-void *memcpy(void *dest, const void *src, size_t n);
 
 memptr free_mem_ptr;
 memptr free_mem_end_ptr;
@@ -225,35 +225,6 @@ void *memset(void *s, int c, size_t n)
 		ss[i] = c;
 	return s;
 }
-#ifdef CONFIG_X86_32
-void *memcpy(void *dest, const void *src, size_t n)
-{
-	int d0, d1, d2;
-	asm volatile(
-		"rep ; movsl\n\t"
-		"movl %4,%%ecx\n\t"
-		"rep ; movsb\n\t"
-		: "=&c" (d0), "=&D" (d1), "=&S" (d2)
-		: "0" (n >> 2), "g" (n & 3), "1" (dest), "2" (src)
-		: "memory");
-
-	return dest;
-}
-#else
-void *memcpy(void *dest, const void *src, size_t n)
-{
-	long d0, d1, d2;
-	asm volatile(
-		"rep ; movsq\n\t"
-		"movq %4,%%rcx\n\t"
-		"rep ; movsb\n\t"
-		: "=&c" (d0), "=&D" (d1), "=&S" (d2)
-		: "0" (n >> 3), "g" (n & 7), "1" (dest), "2" (src)
-		: "memory");
-
-	return dest;
-}
-#endif
 
 static void error(char *x)
 {
diff --git a/arch/x86/boot/compressed/string.c b/arch/x86/boot/compressed/string.c
index 212004e..3b5a82f 100644
--- a/arch/x86/boot/compressed/string.c
+++ b/arch/x86/boot/compressed/string.c
@@ -11,3 +11,36 @@ int memcmp(const void *s1, const void *s2, size_t len)
 }
 
 #include "../string.c"
+
+/* misc.h might pull in string_32.h which has a macro for memcpy. undef that */
+#undef memcpy
+
+#ifdef CONFIG_X86_32
+void *memcpy(void *dest, const void *src, size_t n)
+{
+	int d0, d1, d2;
+	asm volatile(
+		"rep ; movsl\n\t"
+		"movl %4,%%ecx\n\t"
+		"rep ; movsb\n\t"
+		: "=&c" (d0), "=&D" (d1), "=&S" (d2)
+		: "0" (n >> 2), "g" (n & 3), "1" (dest), "2" (src)
+		: "memory");
+
+	return dest;
+}
+#else
+void *memcpy(void *dest, const void *src, size_t n)
+{
+	long d0, d1, d2;
+	asm volatile(
+		"rep ; movsq\n\t"
+		"movq %4,%%rcx\n\t"
+		"rep ; movsb\n\t"
+		: "=&c" (d0), "=&D" (d1), "=&S" (d2)
+		: "0" (n >> 3), "g" (n & 7), "1" (dest), "2" (src)
+		: "memory");
+
+	return dest;
+}
+#endif
-- 
1.8.5.3

[PATCH 4/5] x86/boot: Move memcmp() into string.h and string.c

[Vivek Goyal]

Try to treat memcmp() in same way as memcpy() and memset(). Provide a
declaration in boot/string.h and by default user gets a memcmp() which
maps to builtin function.

Move optimized definition of memcmp() in boot/string.c. Now a user can
do #undef memcmp and link against string.c to use optimzied memcmp().

It also simplifies boot/compressed/string.c where we had to redefine
memcmp(). That extra definition is gone now.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 arch/x86/boot/boot.h              |  8 --------
 arch/x86/boot/compressed/string.c | 11 -----------
 arch/x86/boot/string.c            | 14 ++++++++++++++
 arch/x86/boot/string.h            |  2 ++
 4 files changed, 16 insertions(+), 19 deletions(-)

diff --git a/arch/x86/boot/boot.h b/arch/x86/boot/boot.h
index bed9665..bd49ec6 100644
--- a/arch/x86/boot/boot.h
+++ b/arch/x86/boot/boot.h
@@ -177,14 +177,6 @@ static inline void wrgs32(u32 v, addr_t addr)
 }
 
 /* Note: these only return true/false, not a signed return value! */
-static inline int memcmp(const void *s1, const void *s2, size_t len)
-{
-	u8 diff;
-	asm("repe; cmpsb; setnz %0"
-	    : "=qm" (diff), "+D" (s1), "+S" (s2), "+c" (len));
-	return diff;
-}
-
 static inline int memcmp_fs(const void *s1, addr_t s2, size_t len)
 {
 	u8 diff;
diff --git a/arch/x86/boot/compressed/string.c b/arch/x86/boot/compressed/string.c
index 3b5a82f..920b55e 100644
--- a/arch/x86/boot/compressed/string.c
+++ b/arch/x86/boot/compressed/string.c
@@ -1,15 +1,4 @@
 #include "misc.h"
-
-/* Avoid intereference from any defines in string_32.h */
-#undef memcmp
-int memcmp(const void *s1, const void *s2, size_t len)
-{
-	u8 diff;
-	asm("repe; cmpsb; setnz %0"
-	    : "=qm" (diff), "+D" (s1), "+S" (s2), "+c" (len));
-	return diff;
-}
-
 #include "../string.c"
 
 /* misc.h might pull in string_32.h which has a macro for memcpy. undef that */
diff --git a/arch/x86/boot/string.c b/arch/x86/boot/string.c
index 574dedf..5339040 100644
--- a/arch/x86/boot/string.c
+++ b/arch/x86/boot/string.c
@@ -14,6 +14,20 @@
 
 #include "boot.h"
 
+/*
+ * This file gets included in compressed/string.c which might pull in
+ * string_32.h and which in turn maps memcmp to __builtin_memcmp(). Undo
+ * that first.
+ */
+#undef memcmp
+int memcmp(const void *s1, const void *s2, size_t len)
+{
+	u8 diff;
+	asm("repe; cmpsb; setnz %0"
+	    : "=qm" (diff), "+D" (s1), "+S" (s2), "+c" (len));
+	return diff;
+}
+
 int strcmp(const char *str1, const char *str2)
 {
 	const unsigned char *s1 = (const unsigned char *)str1;
diff --git a/arch/x86/boot/string.h b/arch/x86/boot/string.h
index 10939d8..725e820 100644
--- a/arch/x86/boot/string.h
+++ b/arch/x86/boot/string.h
@@ -8,6 +8,7 @@
 
 void *memcpy(void *dst, const void *src, size_t len);
 void *memset(void *dst, int c, size_t len);
+int memcmp(const void *s1, const void *s2, size_t len);
 
 /*
  * Access builtin version by default. If one needs to use optimized version,
@@ -15,5 +16,6 @@ void *memset(void *dst, int c, size_t len);
  */
 #define memcpy(d,s,l) __builtin_memcpy(d,s,l)
 #define memset(d,c,l) __builtin_memset(d,c,l)
+#define memcmp	__builtin_memcmp
 
 #endif /* BOOT_STRING_H */
-- 
1.8.5.3

[PATCH 5/5] x86/boot: Move memset() definition in compressed/string.c

[Vivek Goyal]

Currently compressed/misc.c needs to link against memset(). I think one of
the reasons of this need is inclusion of various header files which define
static inline functions and use memset() inside these. For example,
include/linux/bitmap.h

I think trying to include "../string.h" and using builtin version of memset
does not work because by the time "#define memset" shows up, it is too
late. Some other header file has already used memset() and expects to
find a definition during link phase.

Currently we have a C definitoin of memset() in misc.c. Move it to
compressed/string.c so that others can use it if need be.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
 arch/x86/boot/compressed/misc.c   | 20 +++++++-------------
 arch/x86/boot/compressed/string.c | 10 ++++++++++
 2 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index 3100092..1768461 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -98,8 +98,14 @@
  */
 #define STATIC		static
 
-#undef memset
 #undef memcpy
+
+/*
+ * Use a normal definition of memset() from string.c. There are already
+ * included header files which expect a definition of memset() and by
+ * the time we define memset macro, it is too late.
+ */
+#undef memset
 #define memzero(s, n)	memset((s), 0, (n))
 
 
@@ -110,8 +116,6 @@ static void error(char *m);
  */
 struct boot_params *real_mode;		/* Pointer to real-mode data */
 
-void *memset(void *s, int c, size_t n);
-
 memptr free_mem_ptr;
 memptr free_mem_end_ptr;
 
@@ -216,16 +220,6 @@ void __putstr(const char *s)
 	outb(0xff & (pos >> 1), vidport+1);
 }
 
-void *memset(void *s, int c, size_t n)
-{
-	int i;
-	char *ss = s;
-
-	for (i = 0; i < n; i++)
-		ss[i] = c;
-	return s;
-}
-
 static void error(char *x)
 {
 	error_putstr("\n\n");
diff --git a/arch/x86/boot/compressed/string.c b/arch/x86/boot/compressed/string.c
index 920b55e..f3c57e3 100644
--- a/arch/x86/boot/compressed/string.c
+++ b/arch/x86/boot/compressed/string.c
@@ -33,3 +33,13 @@ void *memcpy(void *dest, const void *src, size_t n)
 	return dest;
 }
 #endif
+
+void *memset(void *s, int c, size_t n)
+{
+	int i;
+	char *ss = s;
+
+	for (i = 0; i < n; i++)
+		ss[i] = c;
+	return s;
+}
-- 
1.8.5.3

[tip:x86/boot] x86, boot: Undef memcmp before providing a new definition

[tip-bot for Vivek Goyal]

Commit-ID:  aad830938ed8ba175d8060751654f78d4115ea0a
Gitweb:     http://git.kernel.org/tip/aad830938ed8ba175d8060751654f78d4115ea0a
Author:     Vivek Goyal <vgoyal@redhat.com>
AuthorDate: Tue, 18 Mar 2014 15:26:36 -0400
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 19 Mar 2014 15:43:37 -0700

x86, boot: Undef memcmp before providing a new definition

With CONFIG_X86_32=y, string_32.h gets pulled in compressed/string.c by
"misch.h". string_32.h defines a macro to map memcmp to __builtin_memcmp().
And that macro in turn changes the name of memcmp() defined here and
converts it to __builtin_memcmp().

I thought that's not the intention though. We probably want to provide
our own optimized definition of memcmp(). If yes, then undef the memcmp
before we define a new memcmp.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1395170800-11059-2-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/boot/compressed/string.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/boot/compressed/string.c b/arch/x86/boot/compressed/string.c
index ffb9c5c..212004e 100644
--- a/arch/x86/boot/compressed/string.c
+++ b/arch/x86/boot/compressed/string.c
@@ -1,5 +1,7 @@
 #include "misc.h"
 
+/* Avoid intereference from any defines in string_32.h */
+#undef memcmp
 int memcmp(const void *s1, const void *s2, size_t len)
 {
 	u8 diff;

[tip:x86/boot] x86, boot: Create a separate string.h file to provide standard string functions

[tip-bot for Vivek Goyal]

Commit-ID:  c041b5ad8640dd89ccf1411cd2636ef7c1cfee92
Gitweb:     http://git.kernel.org/tip/c041b5ad8640dd89ccf1411cd2636ef7c1cfee92
Author:     Vivek Goyal <vgoyal@redhat.com>
AuthorDate: Tue, 18 Mar 2014 15:26:37 -0400
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 19 Mar 2014 15:43:45 -0700

x86, boot: Create a separate string.h file to provide standard string functions

Create a separate arch/x86/boot/string.h file to provide declaration of
some of the common string functions.

By default memcpy, memset and memcmp functions will default to gcc
builtin functions. If code wants to use an optimized version of any
of these functions, they need to #undef the respective macro and link
against a local file providing definition of undefed function.

For example, arch/x86/boot/* code links against copy.S to get memcpy()
and memcmp() definitions. arch/86/boot/compressed/* links against
compressed/string.c.

There are quite a few places in arch/x86/ where these functions are
used. Idea is to try to consilidate  their declaration and possibly
definitions so that it can be reused.

I am planning to reuse boot/string.h in arch/x86/purgatory/ and use
gcc builtin functions for memcpy, memset and memcmp.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1395170800-11059-3-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/boot/boot.h       |  5 -----
 arch/x86/boot/cpucheck.c   |  1 +
 arch/x86/boot/edd.c        |  1 +
 arch/x86/boot/main.c       |  1 +
 arch/x86/boot/regs.c       |  1 +
 arch/x86/boot/string.h     | 19 +++++++++++++++++++
 arch/x86/boot/video-vesa.c |  1 +
 7 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/arch/x86/boot/boot.h b/arch/x86/boot/boot.h
index 50f8c5e..bed9665 100644
--- a/arch/x86/boot/boot.h
+++ b/arch/x86/boot/boot.h
@@ -228,11 +228,6 @@ void copy_to_fs(addr_t dst, void *src, size_t len);
 void *copy_from_fs(void *dst, addr_t src, size_t len);
 void copy_to_gs(addr_t dst, void *src, size_t len);
 void *copy_from_gs(void *dst, addr_t src, size_t len);
-void *memcpy(void *dst, void *src, size_t len);
-void *memset(void *dst, int c, size_t len);
-
-#define memcpy(d,s,l) __builtin_memcpy(d,s,l)
-#define memset(d,c,l) __builtin_memset(d,c,l)
 
 /* a20.c */
 int enable_a20(void);
diff --git a/arch/x86/boot/cpucheck.c b/arch/x86/boot/cpucheck.c
index 100a9a1..086c4f4 100644
--- a/arch/x86/boot/cpucheck.c
+++ b/arch/x86/boot/cpucheck.c
@@ -27,6 +27,7 @@
 #include <asm/processor-flags.h>
 #include <asm/required-features.h>
 #include <asm/msr-index.h>
+#include "string.h"
 
 static u32 err_flags[NCAPINTS];
 
diff --git a/arch/x86/boot/edd.c b/arch/x86/boot/edd.c
index c501a5b..223e425 100644
--- a/arch/x86/boot/edd.c
+++ b/arch/x86/boot/edd.c
@@ -15,6 +15,7 @@
 
 #include "boot.h"
 #include <linux/edd.h>
+#include "string.h"
 
 #if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
 
diff --git a/arch/x86/boot/main.c b/arch/x86/boot/main.c
index cf6083d..fd6c9f2 100644
--- a/arch/x86/boot/main.c
+++ b/arch/x86/boot/main.c
@@ -14,6 +14,7 @@
  */
 
 #include "boot.h"
+#include "string.h"
 
 struct boot_params boot_params __attribute__((aligned(16)));
 
diff --git a/arch/x86/boot/regs.c b/arch/x86/boot/regs.c
index 958019b..c0fb356 100644
--- a/arch/x86/boot/regs.c
+++ b/arch/x86/boot/regs.c
@@ -17,6 +17,7 @@
  */
 
 #include "boot.h"
+#include "string.h"
 
 void initregs(struct biosregs *reg)
 {
diff --git a/arch/x86/boot/string.h b/arch/x86/boot/string.h
new file mode 100644
index 0000000..10939d8
--- /dev/null
+++ b/arch/x86/boot/string.h
@@ -0,0 +1,19 @@
+#ifndef BOOT_STRING_H
+#define BOOT_STRING_H
+
+/* Undef any of these macros coming from string_32.h. */
+#undef memcpy
+#undef memset
+#undef memcmp
+
+void *memcpy(void *dst, const void *src, size_t len);
+void *memset(void *dst, int c, size_t len);
+
+/*
+ * Access builtin version by default. If one needs to use optimized version,
+ * do "undef memcpy" in .c file and link against right string.c
+ */
+#define memcpy(d,s,l) __builtin_memcpy(d,s,l)
+#define memset(d,c,l) __builtin_memset(d,c,l)
+
+#endif /* BOOT_STRING_H */
diff --git a/arch/x86/boot/video-vesa.c b/arch/x86/boot/video-vesa.c
index 11e8c6e..ba3e100 100644
--- a/arch/x86/boot/video-vesa.c
+++ b/arch/x86/boot/video-vesa.c
@@ -16,6 +16,7 @@
 #include "boot.h"
 #include "video.h"
 #include "vesa.h"
+#include "string.h"
 
 /* VESA information */
 static struct vesa_general_info vginfo;

[tip:x86/boot] x86, boot: Move optimized memcpy() 32/ 64 bit versions to compressed/string.c

[tip-bot for Vivek Goyal]

Commit-ID:  820e8feca06ff744f60e5036c3178dde40b91afc
Gitweb:     http://git.kernel.org/tip/820e8feca06ff744f60e5036c3178dde40b91afc
Author:     Vivek Goyal <vgoyal@redhat.com>
AuthorDate: Tue, 18 Mar 2014 15:26:38 -0400
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 19 Mar 2014 15:43:59 -0700

x86, boot: Move optimized memcpy() 32/64 bit versions to compressed/string.c

Move optimized versions of memcpy to compressed/string.c This will allow
any other code to use these functions too if need be in future. Again
trying to put definition in a common place instead of hiding it in misc.c

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1395170800-11059-4-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/boot/compressed/misc.c   | 31 +------------------------------
 arch/x86/boot/compressed/string.c | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+), 30 deletions(-)

diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index 196eaf3..3100092 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -10,6 +10,7 @@
  */
 
 #include "misc.h"
+#include "../string.h"
 
 /* WARNING!!
  * This code is compiled with -fPIC and it is relocated dynamically
@@ -110,7 +111,6 @@ static void error(char *m);
 struct boot_params *real_mode;		/* Pointer to real-mode data */
 
 void *memset(void *s, int c, size_t n);
-void *memcpy(void *dest, const void *src, size_t n);
 
 memptr free_mem_ptr;
 memptr free_mem_end_ptr;
@@ -225,35 +225,6 @@ void *memset(void *s, int c, size_t n)
 		ss[i] = c;
 	return s;
 }
-#ifdef CONFIG_X86_32
-void *memcpy(void *dest, const void *src, size_t n)
-{
-	int d0, d1, d2;
-	asm volatile(
-		"rep ; movsl\n\t"
-		"movl %4,%%ecx\n\t"
-		"rep ; movsb\n\t"
-		: "=&c" (d0), "=&D" (d1), "=&S" (d2)
-		: "0" (n >> 2), "g" (n & 3), "1" (dest), "2" (src)
-		: "memory");
-
-	return dest;
-}
-#else
-void *memcpy(void *dest, const void *src, size_t n)
-{
-	long d0, d1, d2;
-	asm volatile(
-		"rep ; movsq\n\t"
-		"movq %4,%%rcx\n\t"
-		"rep ; movsb\n\t"
-		: "=&c" (d0), "=&D" (d1), "=&S" (d2)
-		: "0" (n >> 3), "g" (n & 7), "1" (dest), "2" (src)
-		: "memory");
-
-	return dest;
-}
-#endif
 
 static void error(char *x)
 {
diff --git a/arch/x86/boot/compressed/string.c b/arch/x86/boot/compressed/string.c
index 212004e..3b5a82f 100644
--- a/arch/x86/boot/compressed/string.c
+++ b/arch/x86/boot/compressed/string.c
@@ -11,3 +11,36 @@ int memcmp(const void *s1, const void *s2, size_t len)
 }
 
 #include "../string.c"
+
+/* misc.h might pull in string_32.h which has a macro for memcpy. undef that */
+#undef memcpy
+
+#ifdef CONFIG_X86_32
+void *memcpy(void *dest, const void *src, size_t n)
+{
+	int d0, d1, d2;
+	asm volatile(
+		"rep ; movsl\n\t"
+		"movl %4,%%ecx\n\t"
+		"rep ; movsb\n\t"
+		: "=&c" (d0), "=&D" (d1), "=&S" (d2)
+		: "0" (n >> 2), "g" (n & 3), "1" (dest), "2" (src)
+		: "memory");
+
+	return dest;
+}
+#else
+void *memcpy(void *dest, const void *src, size_t n)
+{
+	long d0, d1, d2;
+	asm volatile(
+		"rep ; movsq\n\t"
+		"movq %4,%%rcx\n\t"
+		"rep ; movsb\n\t"
+		: "=&c" (d0), "=&D" (d1), "=&S" (d2)
+		: "0" (n >> 3), "g" (n & 7), "1" (dest), "2" (src)
+		: "memory");
+
+	return dest;
+}
+#endif

[tip:x86/boot] x86, boot: Move memcmp() into string.h and string.c

[tip-bot for Vivek Goyal]

Commit-ID:  fb4cac573ef6dce8d7543b68306566561c2e5725
Gitweb:     http://git.kernel.org/tip/fb4cac573ef6dce8d7543b68306566561c2e5725
Author:     Vivek Goyal <vgoyal@redhat.com>
AuthorDate: Tue, 18 Mar 2014 15:26:39 -0400
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 19 Mar 2014 15:44:04 -0700

x86, boot: Move memcmp() into string.h and string.c

Try to treat memcmp() in same way as memcpy() and memset(). Provide a
declaration in boot/string.h and by default user gets a memcmp() which
maps to builtin function.

Move optimized definition of memcmp() in boot/string.c. Now a user can
do #undef memcmp and link against string.c to use optimzied memcmp().

It also simplifies boot/compressed/string.c where we had to redefine
memcmp(). That extra definition is gone now.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1395170800-11059-5-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/boot/boot.h              |  8 --------
 arch/x86/boot/compressed/string.c | 11 -----------
 arch/x86/boot/string.c            | 14 ++++++++++++++
 arch/x86/boot/string.h            |  2 ++
 4 files changed, 16 insertions(+), 19 deletions(-)

diff --git a/arch/x86/boot/boot.h b/arch/x86/boot/boot.h
index bed9665..bd49ec6 100644
--- a/arch/x86/boot/boot.h
+++ b/arch/x86/boot/boot.h
@@ -177,14 +177,6 @@ static inline void wrgs32(u32 v, addr_t addr)
 }
 
 /* Note: these only return true/false, not a signed return value! */
-static inline int memcmp(const void *s1, const void *s2, size_t len)
-{
-	u8 diff;
-	asm("repe; cmpsb; setnz %0"
-	    : "=qm" (diff), "+D" (s1), "+S" (s2), "+c" (len));
-	return diff;
-}
-
 static inline int memcmp_fs(const void *s1, addr_t s2, size_t len)
 {
 	u8 diff;
diff --git a/arch/x86/boot/compressed/string.c b/arch/x86/boot/compressed/string.c
index 3b5a82f..920b55e 100644
--- a/arch/x86/boot/compressed/string.c
+++ b/arch/x86/boot/compressed/string.c
@@ -1,15 +1,4 @@
 #include "misc.h"
-
-/* Avoid intereference from any defines in string_32.h */
-#undef memcmp
-int memcmp(const void *s1, const void *s2, size_t len)
-{
-	u8 diff;
-	asm("repe; cmpsb; setnz %0"
-	    : "=qm" (diff), "+D" (s1), "+S" (s2), "+c" (len));
-	return diff;
-}
-
 #include "../string.c"
 
 /* misc.h might pull in string_32.h which has a macro for memcpy. undef that */
diff --git a/arch/x86/boot/string.c b/arch/x86/boot/string.c
index 574dedf..5339040 100644
--- a/arch/x86/boot/string.c
+++ b/arch/x86/boot/string.c
@@ -14,6 +14,20 @@
 
 #include "boot.h"
 
+/*
+ * This file gets included in compressed/string.c which might pull in
+ * string_32.h and which in turn maps memcmp to __builtin_memcmp(). Undo
+ * that first.
+ */
+#undef memcmp
+int memcmp(const void *s1, const void *s2, size_t len)
+{
+	u8 diff;
+	asm("repe; cmpsb; setnz %0"
+	    : "=qm" (diff), "+D" (s1), "+S" (s2), "+c" (len));
+	return diff;
+}
+
 int strcmp(const char *str1, const char *str2)
 {
 	const unsigned char *s1 = (const unsigned char *)str1;
diff --git a/arch/x86/boot/string.h b/arch/x86/boot/string.h
index 10939d8..725e820 100644
--- a/arch/x86/boot/string.h
+++ b/arch/x86/boot/string.h
@@ -8,6 +8,7 @@
 
 void *memcpy(void *dst, const void *src, size_t len);
 void *memset(void *dst, int c, size_t len);
+int memcmp(const void *s1, const void *s2, size_t len);
 
 /*
  * Access builtin version by default. If one needs to use optimized version,
@@ -15,5 +16,6 @@ void *memset(void *dst, int c, size_t len);
  */
 #define memcpy(d,s,l) __builtin_memcpy(d,s,l)
 #define memset(d,c,l) __builtin_memset(d,c,l)
+#define memcmp	__builtin_memcmp
 
 #endif /* BOOT_STRING_H */

[tip:x86/boot] x86, boot: Move memset() definition in compressed/ string.c

[tip-bot for Vivek Goyal]

Commit-ID:  04999550f93234bf05597a9b7d26e2bfe27ba883
Gitweb:     http://git.kernel.org/tip/04999550f93234bf05597a9b7d26e2bfe27ba883
Author:     Vivek Goyal <vgoyal@redhat.com>
AuthorDate: Tue, 18 Mar 2014 15:26:40 -0400
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 19 Mar 2014 15:44:09 -0700

x86, boot: Move memset() definition in compressed/string.c

Currently compressed/misc.c needs to link against memset(). I think one of
the reasons of this need is inclusion of various header files which define
static inline functions and use memset() inside these. For example,
include/linux/bitmap.h

I think trying to include "../string.h" and using builtin version of memset
does not work because by the time "#define memset" shows up, it is too
late. Some other header file has already used memset() and expects to
find a definition during link phase.

Currently we have a C definitoin of memset() in misc.c. Move it to
compressed/string.c so that others can use it if need be.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1395170800-11059-6-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/boot/compressed/misc.c   | 20 +++++++-------------
 arch/x86/boot/compressed/string.c | 10 ++++++++++
 2 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index 3100092..1768461 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -98,8 +98,14 @@
  */
 #define STATIC		static
 
-#undef memset
 #undef memcpy
+
+/*
+ * Use a normal definition of memset() from string.c. There are already
+ * included header files which expect a definition of memset() and by
+ * the time we define memset macro, it is too late.
+ */
+#undef memset
 #define memzero(s, n)	memset((s), 0, (n))
 
 
@@ -110,8 +116,6 @@ static void error(char *m);
  */
 struct boot_params *real_mode;		/* Pointer to real-mode data */
 
-void *memset(void *s, int c, size_t n);
-
 memptr free_mem_ptr;
 memptr free_mem_end_ptr;
 
@@ -216,16 +220,6 @@ void __putstr(const char *s)
 	outb(0xff & (pos >> 1), vidport+1);
 }
 
-void *memset(void *s, int c, size_t n)
-{
-	int i;
-	char *ss = s;
-
-	for (i = 0; i < n; i++)
-		ss[i] = c;
-	return s;
-}
-
 static void error(char *x)
 {
 	error_putstr("\n\n");
diff --git a/arch/x86/boot/compressed/string.c b/arch/x86/boot/compressed/string.c
index 920b55e..f3c57e3 100644
--- a/arch/x86/boot/compressed/string.c
+++ b/arch/x86/boot/compressed/string.c
@@ -33,3 +33,13 @@ void *memcpy(void *dest, const void *src, size_t n)
 	return dest;
 }
 #endif
+
+void *memset(void *s, int c, size_t n)
+{
+	int i;
+	char *ss = s;
+
+	for (i = 0; i < n; i++)
+		ss[i] = c;
+	return s;
+}