[GIT PULL] asm-generic fixes

[GIT PULL] asm-generic fixes

[Arnd Bergmann]

Hi Linus,

Please pull this set of fixes for include/asm-generic and
the checksum code from

git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/asm-generic.git for-linus

---
Arnd Bergmann (4):
  asm-generic: drop HARDIRQ_BITS definition from hardirq.h
  asm-generic: list Arnd as asm-generic maintainer
  asm-generic: hook up new system calls
  lib/checksum.c: fix endianess bug

Mike Frysinger (2):
  asm-generic: uaccess: add missing access_ok() check to strnlen_user()
  asm-generic: uaccess: fix up local access_ok() usage

Paul Mundt (1):
  asm-generic: add dummy pgprot_noncached()

 MAINTAINERS                   |    8 ++++++++
 include/asm-generic/hardirq.h |   13 -------------
 include/asm-generic/pgtable.h |    4 ++++
 include/asm-generic/uaccess.h |   14 ++++++++------
 include/asm-generic/unistd.h  |    7 ++++++-
 lib/checksum.c                |   10 +++++++++-
 6 files changed, 35 insertions(+), 21 deletions(-)

diff --git a/MAINTAINERS b/MAINTAINERS
index 02f6f78..b85cf35 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2482,6 +2482,14 @@ F:	drivers/net/wan/pc300too.c
 F:	drivers/net/wan/pci200syn.c
 F:	drivers/net/wan/wanxl*
 
+GENERIC INCLUDE/ASM HEADER FILES
+P:	Arnd Bergmann
+M:	arnd@arndb.de
+L:	linux-arch@vger.kernel.org
+T:	git git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic.git
+S:	Maintained
+F:	include/asm-generic
+
 GFS2 FILE SYSTEM
 P:	Steven Whitehouse
 M:	swhiteho@redhat.com
diff --git a/include/asm-generic/hardirq.h b/include/asm-generic/hardirq.h
index 3d5d2c9..23bb4da 100644
--- a/include/asm-generic/hardirq.h
+++ b/include/asm-generic/hardirq.h
@@ -11,19 +11,6 @@ typedef struct {
 
 #include <linux/irq_cpustat.h>	/* Standard mappings for irq_cpustat_t above */
 
-#ifndef HARDIRQ_BITS
-#define HARDIRQ_BITS	8
-#endif
-
-/*
- * The hardirq mask has to be large enough to have
- * space for potentially all IRQ sources in the system
- * nesting on a single CPU:
- */
-#if (1 << HARDIRQ_BITS) < NR_IRQS
-# error HARDIRQ_BITS is too low!
-#endif
-
 #ifndef ack_bad_irq
 static inline void ack_bad_irq(unsigned int irq)
 {
diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index e410f60..e2bd73e 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -129,6 +129,10 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addres
 #define move_pte(pte, prot, old_addr, new_addr)	(pte)
 #endif
 
+#ifndef pgprot_noncached
+#define pgprot_noncached(prot)	(prot)
+#endif
+
 #ifndef pgprot_writecombine
 #define pgprot_writecombine pgprot_noncached
 #endif
diff --git a/include/asm-generic/uaccess.h b/include/asm-generic/uaccess.h
index 6d8cab2..b218b85 100644
--- a/include/asm-generic/uaccess.h
+++ b/include/asm-generic/uaccess.h
@@ -163,7 +163,7 @@ static inline __must_check long __copy_to_user(void __user *to,
 #define put_user(x, ptr)					\
 ({								\
 	might_sleep();						\
-	__access_ok(ptr, sizeof (*ptr)) ?			\
+	access_ok(VERIFY_WRITE, ptr, sizeof(*ptr)) ?		\
 		__put_user(x, ptr) :				\
 		-EFAULT;					\
 })
@@ -219,7 +219,7 @@ extern int __put_user_bad(void) __attribute__((noreturn));
 #define get_user(x, ptr)					\
 ({								\
 	might_sleep();						\
-	__access_ok(ptr, sizeof (*ptr)) ?			\
+	access_ok(VERIFY_READ, ptr, sizeof(*ptr)) ?		\
 		__get_user(x, ptr) :				\
 		-EFAULT;					\
 })
@@ -244,7 +244,7 @@ static inline long copy_from_user(void *to,
 		const void __user * from, unsigned long n)
 {
 	might_sleep();
-	if (__access_ok(from, n))
+	if (access_ok(VERIFY_READ, from, n))
 		return __copy_from_user(to, from, n);
 	else
 		return n;
@@ -254,7 +254,7 @@ static inline long copy_to_user(void __user *to,
 		const void *from, unsigned long n)
 {
 	might_sleep();
-	if (__access_ok(to, n))
+	if (access_ok(VERIFY_WRITE, to, n))
 		return __copy_to_user(to, from, n);
 	else
 		return n;
@@ -278,7 +278,7 @@ __strncpy_from_user(char *dst, const char __user *src, long count)
 static inline long
 strncpy_from_user(char *dst, const char __user *src, long count)
 {
-	if (!__access_ok(src, 1))
+	if (!access_ok(VERIFY_READ, src, 1))
 		return -EFAULT;
 	return __strncpy_from_user(dst, src, count);
 }
@@ -291,6 +291,8 @@ strncpy_from_user(char *dst, const char __user *src, long count)
 #ifndef strnlen_user
 static inline long strnlen_user(const char __user *src, long n)
 {
+	if (!access_ok(VERIFY_READ, src, 1))
+		return 0;
 	return strlen((void * __force)src) + 1;
 }
 #endif
@@ -316,7 +318,7 @@ static inline __must_check unsigned long
 clear_user(void __user *to, unsigned long n)
 {
 	might_sleep();
-	if (!__access_ok(to, n))
+	if (!access_ok(VERIFY_WRITE, to, n))
 		return n;
 
 	return __clear_user(to, n);
diff --git a/include/asm-generic/unistd.h b/include/asm-generic/unistd.h
index 5b34b62..1125e5a 100644
--- a/include/asm-generic/unistd.h
+++ b/include/asm-generic/unistd.h
@@ -618,8 +618,13 @@ __SYSCALL(__NR_migrate_pages, sys_migrate_pages)
 __SYSCALL(__NR_move_pages, sys_move_pages)
 #endif
 
+#define __NR_rt_tgsigqueueinfo 240
+__SYSCALL(__NR_rt_tgsigqueueinfo, sys_rt_tgsigqueueinfo)
+#define __NR_perf_counter_open 241
+__SYSCALL(__NR_perf_counter_open, sys_perf_counter_open)
+
 #undef __NR_syscalls
-#define __NR_syscalls 240
+#define __NR_syscalls 242
 
 /*
  * All syscalls below here should go away really,
diff --git a/lib/checksum.c b/lib/checksum.c
index 12e5a1c..b2e2fd4 100644
--- a/lib/checksum.c
+++ b/lib/checksum.c
@@ -55,7 +55,11 @@ static unsigned int do_csum(const unsigned char *buff, int len)
 		goto out;
 	odd = 1 & (unsigned long) buff;
 	if (odd) {
+#ifdef __LITTLE_ENDIAN
 		result = *buff;
+#else
+		result += (*buff << 8);
+#endif
 		len--;
 		buff++;
 	}
@@ -71,7 +75,7 @@ static unsigned int do_csum(const unsigned char *buff, int len)
 		if (count) {
 			unsigned long carry = 0;
 			do {
-				unsigned long w = *(unsigned long *) buff;
+				unsigned long w = *(unsigned int *) buff;
 				count--;
 				buff += 4;
 				result += carry;
@@ -87,7 +91,11 @@ static unsigned int do_csum(const unsigned char *buff, int len)
 		}
 	}
 	if (len & 1)
+#ifdef __LITTLE_ENDIAN
+		result += *buff;
+#else
 		result += (*buff << 8);
+#endif
 	result = from32to16(result);
 	if (odd)
 		result = ((result >> 8) & 0xff) | ((result & 0xff) << 8);

Re: [GIT PULL] asm-generic fixes

[Linus Torvalds]

On Tue, 23 Jun 2009, Arnd Bergmann wrote:
> @@ -71,7 +75,7 @@ static unsigned int do_csum(const unsigned char *buff, int len)
>  		if (count) {
>  			unsigned long carry = 0;
>  			do {
> -				unsigned long w = *(unsigned long *) buff;
> +				unsigned long w = *(unsigned int *) buff;
>  				count--;
>  				buff += 4;
>  				result += carry;

I don't think this is sufficient.

You might need to make 'result', 'carry', and 'w' be 'unsigned int' too.

Why? Because the final folding is only doen from 32-bit to 16 bit, we 
don't do the whole 64-bit to 32-bit to 16-bit chain.

Now, it's possible (even likely) that even with a 64-bit word, we'll never 
actually do large enough areas that 'result' would ever have very many 
bits set in the 32+ bit region, and since we do end up folding to 16 bits 
twice (once after the loop and once at the end), it _probably_ gets things 
right in most cases. But I doubt "probably" is strong enough. Somebody 
should check.

Or just see arch/alpha/lib/checksum.c, which does the whole 64-bit case.
Maybe lib/checksum.c should be lib/checksum_{32,64}.c.

		Linus

Re: [GIT PULL] asm-generic fixes

[Arnd Bergmann]

On Tuesday 23 June 2009, Linus Torvalds wrote:
> You might need to make 'result', 'carry', and 'w' be 'unsigned int' too.

Yes, you're right.

> Now, it's possible (even likely) that even with a 64-bit word, we'll never 
> actually do large enough areas that 'result' would ever have very many 
> bits set in the 32+ bit region, and since we do end up folding to 16 bits 
> twice (once after the loop and once at the end), it probably gets things 
> right in most cases. But I doubt "probably" is strong enough. Somebody 
> should check.

I think it would overrun only if we have more than 65536 u32 words of
0xffffffff in a single IP packet, on a 64 bit machine. A more obvious
reason to change it is that it relies on from32to16() actually behaving
like a from47to16() function on 64-bit. Changing it to use unsigned int
throughout makes it both more obvious and more consistent between
32 and 64 bit unsigned long types.

> Or just see arch/alpha/lib/checksum.c, which does the whole 64-bit case.
> Maybe lib/checksum.c should be lib/checksum_{32,64}.c.

Mike Frysinger earlier suggested just making the do_csum function optional
in this file because this is the one that most architectures would override.

The alpha code is the only 64-bit platform implementing do_csum in C, so
if Richard wants to use the generic code in its current form, he could simply
override the do_csum implementation.

I've now added these two patches:

commit 217a8c7b6af924379a2083439b4bb606f332e7b1
Author: Arnd Bergmann <arnd@arndb.de>
Date:   Tue Jun 23 21:37:26 2009 +0200

    lib/checksum.c: make do_csum optional
    
    Mike Frysinger suggested that do_csum should be optional
    so that an architecture can use the generic checksum code
    but still provide an optimized fast-path for the most
    critical function.
    
    This can mean an implementation using inline assembly,
    or in case of Alpha one using 64-bit arithmetic in C.
    
    Cc: Mike Frysinger <vapier@gentoo.org>
    Signed-off-by: Arnd Bergmann <arnd@arndb.de>

diff --git a/lib/checksum.c b/lib/checksum.c
index 886b48d..b08c2d0 100644
--- a/lib/checksum.c
+++ b/lib/checksum.c
@@ -37,6 +37,7 @@
 
 #include <asm/byteorder.h>
 
+#ifndef do_csum
 static inline unsigned short from32to16(unsigned int x)
 {
 	/* add up 16-bit and 16-bit for 16+c bit */
@@ -102,6 +103,7 @@ static unsigned int do_csum(const unsigned char *buff, int len)
 out:
 	return result;
 }
+#endif
 
 /*
  *	This is a version of ip_compute_csum() optimized for IP headers,

commit 5cb59758c3e2170b24e9c0d659eb6c03872155c0
Author: Arnd Bergmann <arnd@arndb.de>
Date:   Tue Jun 23 21:22:58 2009 +0200

    lib/checksum.c: use 32-bit arithmetic consistently
    
    The use of 'unsigned long' variables in the 32-bit part of do_csum()
    is confusing at best, and potentially broken for long input on 64-bit
    machines.
    
    This changes the code to use 'unsigned int' instead, which makes
    the code behave in the same (correct) way on both 32 and 64 bit
    machines.
    
    Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
    Signed-off-by: Arnd Bergmann <arnd@arndb.de>

diff --git a/lib/checksum.c b/lib/checksum.c
index b2e2fd4..886b48d 100644
--- a/lib/checksum.c
+++ b/lib/checksum.c
@@ -37,7 +37,7 @@
 
 #include <asm/byteorder.h>
 
-static inline unsigned short from32to16(unsigned long x)
+static inline unsigned short from32to16(unsigned int x)
 {
 	/* add up 16-bit and 16-bit for 16+c bit */
 	x = (x & 0xffff) + (x >> 16);
@@ -49,7 +49,7 @@ static inline unsigned short from32to16(unsigned long x)
 static unsigned int do_csum(const unsigned char *buff, int len)
 {
 	int odd, count;
-	unsigned long result = 0;
+	unsigned int result = 0;
 
 	if (len <= 0)
 		goto out;
@@ -73,9 +73,9 @@ static unsigned int do_csum(const unsigned char *buff, int len)
 		}
 		count >>= 1;		/* nr of 32-bit words.. */
 		if (count) {
-			unsigned long carry = 0;
+			unsigned int carry = 0;
 			do {
-				unsigned long w = *(unsigned int *) buff;
+				unsigned int w = *(unsigned int *) buff;
 				count--;
 				buff += 4;
 				result += carry;