Remove 'type' argument from access_ok() function

Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.

It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access.  But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.

A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model.  And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.

This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.

There were a couple of notable cases:

 - csky still had the old "verify_area()" name as an alias.

 - the iter_iov code had magical hardcoded knowledge of the actual
   values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
   really used it)

 - microblaze used the type argument for a debug printout

but other than those oddities this should be a total no-op patch.

I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something.  Any missed conversion should be trivially fixable, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

4 files changed, 11 insertions, 19 deletions

diff --git a/arch/csky/abiv1/alignment.c b/arch/csky/abiv1/alignment.c
index 60205e98fb87..d789be36eb4f 100644
--- a/arch/csky/abiv1/alignment.c
+++ b/arch/csky/abiv1/alignment.c
@@ -32,7 +32,7 @@ static int ldb_asm(uint32_t addr, uint32_t *valp)
 	uint32_t val;
 	int err;
 
-	if (!access_ok(VERIFY_READ, (void *)addr, 1))
+	if (!access_ok((void *)addr, 1))
 		return 1;
 
 	asm volatile (
@@ -67,7 +67,7 @@ static int stb_asm(uint32_t addr, uint32_t val)
 {
 	int err;
 
-	if (!access_ok(VERIFY_WRITE, (void *)addr, 1))
+	if (!access_ok((void *)addr, 1))
 		return 1;
 
 	asm volatile (
diff --git a/arch/csky/include/asm/uaccess.h b/arch/csky/include/asm/uaccess.h
index acaf0e210d81..eaa1c3403a42 100644
--- a/arch/csky/include/asm/uaccess.h
+++ b/arch/csky/include/asm/uaccess.h
@@ -16,10 +16,7 @@
 #include <linux/version.h>
 #include <asm/segment.h>
 
-#define VERIFY_READ	0
-#define VERIFY_WRITE	1
-
-static inline int access_ok(int type, const void *addr, unsigned long size)
+static inline int access_ok(const void *addr, unsigned long size)
 {
 	unsigned long limit = current_thread_info()->addr_limit.seg;
 
@@ -27,12 +24,7 @@ static inline int access_ok(int type, const void *addr, unsigned long size)
 		((unsigned long)(addr + size) < limit));
 }
 
-static inline int verify_area(int type, const void *addr, unsigned long size)
-{
-	return access_ok(type, addr, size) ? 0 : -EFAULT;
-}
-
-#define __addr_ok(addr) (access_ok(VERIFY_READ, addr, 0))
+#define __addr_ok(addr) (access_ok(addr, 0))
 
 extern int __put_user_bad(void);
 
@@ -91,7 +83,7 @@ extern int __put_user_bad(void);
 	long __pu_err = -EFAULT;					\
 	typeof(*(ptr)) *__pu_addr = (ptr);				\
 	typeof(*(ptr)) __pu_val = (typeof(*(ptr)))(x);			\
-	if (access_ok(VERIFY_WRITE, __pu_addr, size) && __pu_addr)	\
+	if (access_ok(__pu_addr, size) && __pu_addr)	\
 		__put_user_size(__pu_val, __pu_addr, (size), __pu_err);	\
 	__pu_err;							\
 })
@@ -217,7 +209,7 @@ do {								\
 ({								\
 	int __gu_err = -EFAULT;					\
 	const __typeof__(*(ptr)) __user *__gu_ptr = (ptr);	\
-	if (access_ok(VERIFY_READ, __gu_ptr, size) && __gu_ptr)	\
+	if (access_ok(__gu_ptr, size) && __gu_ptr)	\
 		__get_user_size(x, __gu_ptr, size, __gu_err);	\
 	__gu_err;						\
 })
diff --git a/arch/csky/kernel/signal.c b/arch/csky/kernel/signal.c
index 66e1b729b10b..9967c10eee2b 100644
--- a/arch/csky/kernel/signal.c
+++ b/arch/csky/kernel/signal.c
@@ -88,7 +88,7 @@ do_rt_sigreturn(void)
 	struct pt_regs *regs = current_pt_regs();
 	struct rt_sigframe *frame = (struct rt_sigframe *)(regs->usp);
 
-	if (verify_area(VERIFY_READ, frame, sizeof(*frame)))
+	if (!access_ok(frame, sizeof(*frame)))
 		goto badframe;
 	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
 		goto badframe;
diff --git a/arch/csky/lib/usercopy.c b/arch/csky/lib/usercopy.c
index ac9170e2cbb8..647a23986fb5 100644
--- a/arch/csky/lib/usercopy.c
+++ b/arch/csky/lib/usercopy.c
@@ -7,7 +7,7 @@
 unsigned long raw_copy_from_user(void *to, const void *from,
 			unsigned long n)
 {
-	if (access_ok(VERIFY_READ, from, n))
+	if (access_ok(from, n))
 		__copy_user_zeroing(to, from, n);
 	else
 		memset(to, 0, n);
@@ -18,7 +18,7 @@ EXPORT_SYMBOL(raw_copy_from_user);
 unsigned long raw_copy_to_user(void *to, const void *from,
 			unsigned long n)
 {
-	if (access_ok(VERIFY_WRITE, to, n))
+	if (access_ok(to, n))
 		__copy_user(to, from, n);
 	return n;
 }
@@ -113,7 +113,7 @@ long strncpy_from_user(char *dst, const char *src, long count)
 {
 	long res = -EFAULT;
 
-	if (access_ok(VERIFY_READ, src, 1))
+	if (access_ok(src, 1))
 		__do_strncpy_from_user(dst, src, count, res);
 	return res;
 }
@@ -236,7 +236,7 @@ do {							\
 unsigned long
 clear_user(void __user *to, unsigned long n)
 {
-	if (access_ok(VERIFY_WRITE, to, n))
+	if (access_ok(to, n))
 		__do_clear_user(to, n);
 	return n;
 }