From: Ralf Baechle <ralf@linux-mips.org>
To: Richard Sandiford <rsandifo@redhat.com>
Cc: Atsushi Nemoto <anemo@mba.ocn.ne.jp>, linux-mips@linux-mips.org
Subject: Re: gcc 3.3.4/3.4.1 and get_user
Date: Mon, 20 Sep 2004 19:10:21 +0200 [thread overview]
Message-ID: <20040920171021.GA25371@linux-mips.org> (raw)
In-Reply-To: <20040920154042.GB5150@linux-mips.org>
On Mon, Sep 20, 2004 at 05:40:42PM +0200, Ralf Baechle wrote:
> The purpose of this was to avoid a warning about __gu_val possibly being
> used uninitialized without inflating the code. I've got a better solution
> that'll actually shrinks the code size of my defconfig build by 5448
> bytes. Untested patch below.
And here the same for 2.4. Actually this is a straight backport of the
2.6 uaccess.h to 2.4 so with this patch include/asm-mips/uaccess.h and
include/asm-mips64/uaccess.h are going to be identical.
Ralf
Index: include/asm-mips/uaccess.h
===================================================================
RCS file: /home/cvs/linux/include/asm-mips/uaccess.h,v
retrieving revision 1.19.2.2
diff -u -r1.19.2.2 uaccess.h
--- include/asm-mips/uaccess.h 14 Sep 2003 20:55:20 -0000 1.19.2.2
+++ include/asm-mips/uaccess.h 20 Sep 2004 17:04:42 -0000
@@ -3,19 +3,17 @@
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
- * Copyright (C) 1996, 1997, 1998, 1999, 2000, 03 by Ralf Baechle
+ * Copyright (C) 1996, 1997, 1998, 1999, 2000, 03, 04 by Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
*/
#ifndef _ASM_UACCESS_H
#define _ASM_UACCESS_H
+#include <linux/config.h>
#include <linux/compiler.h>
#include <linux/errno.h>
#include <linux/sched.h>
-#define STR(x) __STR(x)
-#define __STR(x) #x
-
/*
* The fs value determines whether argument validity checking should be
* performed or not. If get_fs() == USER_DS, checking is performed, with
@@ -23,15 +21,47 @@
*
* For historical reasons, these macros are grossly misnamed.
*/
-#define KERNEL_DS ((mm_segment_t) { (unsigned long) 0L })
-#define USER_DS ((mm_segment_t) { (unsigned long) -1L })
+#ifdef CONFIG_MIPS32
+
+#define __UA_LIMIT 0x80000000UL
+
+#define __UA_ADDR ".word"
+#define __UA_LA "la"
+#define __UA_ADDU "addu"
+#define __UA_t0 "$8"
+#define __UA_t1 "$9"
+
+#endif /* CONFIG_MIPS32 */
+
+#ifdef CONFIG_MIPS64
+
+#define __UA_LIMIT (- TASK_SIZE)
+
+#define __UA_ADDR ".dword"
+#define __UA_LA "dla"
+#define __UA_ADDU "daddu"
+#define __UA_t0 "$12"
+#define __UA_t1 "$13"
+
+#endif /* CONFIG_MIPS64 */
+
+/*
+ * USER_DS is a bitmask that has the bits set that may not be set in a valid
+ * userspace address. Note that we limit 32-bit userspace to 0x7fff8000 but
+ * the arithmetic we're doing only works if the limit is a power of two, so
+ * we use 0x80000000 here on 32-bit kernels. If a process passes an invalid
+ * address in this range it's the process's problem, not ours :-)
+ */
+
+#define KERNEL_DS ((mm_segment_t) { 0UL })
+#define USER_DS ((mm_segment_t) { __UA_LIMIT })
#define VERIFY_READ 0
#define VERIFY_WRITE 1
-#define get_fs() (current->thread.current_ds)
#define get_ds() (KERNEL_DS)
-#define set_fs(x) (current->thread.current_ds=(x))
+#define get_fs() (current->thread.current_ds)
+#define set_fs(x) (current->thread.current_ds = (x))
#define segment_eq(a,b) ((a).seg == (b).seg)
@@ -45,14 +75,12 @@
* - AND "size" doesn't have any high-bits set
* - AND "addr+size" doesn't have any high-bits set
* - OR we are in kernel mode.
+ *
+ * __ua_size() is a trick to avoid runtime checking of positive constant
+ * sizes; for those we already know at compile time that the size is ok.
*/
#define __ua_size(size) \
- (__builtin_constant_p(size) && (signed long) (size) > 0 ? 0 : (size))
-
-#define __access_ok(addr,size,mask) \
- (((signed long)((mask)&(addr | (addr + size) | __ua_size(size)))) >= 0)
-
-#define __access_mask ((long)(get_fs().seg))
+ ((__builtin_constant_p(size) && (signed long) (size) > 0) ? 0 : (size))
/*
* access_ok: - Checks if a user space pointer is valid
@@ -73,8 +101,14 @@
* checks that the pointer is in the user space range - after calling
* this function, memory access functions may still return -EFAULT.
*/
+
+#define __access_mask get_fs().seg
+
+#define __access_ok(addr, size, mask) \
+ (((signed long)((mask) & ((addr) | ((addr) + (size)) | __ua_size(size)))) == 0)
+
#define access_ok(type, addr, size) \
- likely(__access_ok((unsigned long)(addr), (size), __access_mask))
+ likely(__access_ok((unsigned long)(addr), (size),__access_mask))
/*
* verify_area: - Obsolete, use access_ok()
@@ -190,88 +224,84 @@
* for 32 bit mode and old iron.
*/
#ifdef __mips64
-#define __GET_USER_DW __get_user_asm("ld")
+#define __GET_USER_DW(__gu_err) __get_user_asm("ld", __gu_err)
#else
-#define __GET_USER_DW __get_user_asm_ll32
+#define __GET_USER_DW(__gu_err) __get_user_asm_ll32(__gu_err)
#endif
#define __get_user_nocheck(x,ptr,size) \
({ \
- long __gu_err; \
- __typeof(*(ptr)) __gu_val; \
+ long __gu_err = 0; \
+ __typeof(*(ptr)) __gu_val = 0; \
long __gu_addr; \
- __asm__("":"=r" (__gu_val)); \
__gu_addr = (long) (ptr); \
- __asm__("":"=r" (__gu_err)); \
switch (size) { \
- case 1: __get_user_asm("lb"); break; \
- case 2: __get_user_asm("lh"); break; \
- case 4: __get_user_asm("lw"); break; \
- case 8: __GET_USER_DW; break; \
- default: __get_user_unknown(); break; \
- } x = (__typeof__(*(ptr))) __gu_val; \
+ case 1: __get_user_asm("lb", __gu_err); break; \
+ case 2: __get_user_asm("lh", __gu_err); break; \
+ case 4: __get_user_asm("lw", __gu_err); break; \
+ case 8: __GET_USER_DW(__gu_err); break; \
+ default: __get_user_unknown(); break; \
+ } \
+ x = (__typeof__(*(ptr))) __gu_val; \
__gu_err; \
})
#define __get_user_check(x,ptr,size) \
({ \
- long __gu_err; \
- __typeof__(*(ptr)) __gu_val; \
+ long __gu_err = 0; \
+ __typeof__(*(ptr)) __gu_val = 0; \
long __gu_addr; \
- __asm__("":"=r" (__gu_val)); \
__gu_addr = (long) (ptr); \
- __asm__("":"=r" (__gu_err)); \
- if (access_ok(VERIFY_READ, __gu_addr, size)) { \
+ if (access_ok(VERIFY_READ,__gu_addr,size)) { \
switch (size) { \
- case 1: __get_user_asm("lb"); break; \
- case 2: __get_user_asm("lh"); break; \
- case 4: __get_user_asm("lw"); break; \
- case 8: __GET_USER_DW; break; \
+ case 1: __get_user_asm("lb", __gu_err); break; \
+ case 2: __get_user_asm("lh", __gu_err); break; \
+ case 4: __get_user_asm("lw", __gu_err); break; \
+ case 8: __GET_USER_DW(__gu_err); break; \
default: __get_user_unknown(); break; \
} \
- } x = (__typeof__(*(ptr))) __gu_val; \
- __gu_err; \
+ } \
+ x = (__typeof__(*(ptr))) __gu_val; \
+ __gu_err; \
})
-#define __get_user_asm(insn) \
+#define __get_user_asm(insn,__gu_err) \
({ \
__asm__ __volatile__( \
- "1:\t" insn "\t%1,%2\n\t" \
- "move\t%0,$0\n" \
- "2:\n\t" \
- ".section\t.fixup,\"ax\"\n" \
- "3:\tli\t%0,%3\n\t" \
- "move\t%1,$0\n\t" \
- "j\t2b\n\t" \
- ".previous\n\t" \
- ".section\t__ex_table,\"a\"\n\t" \
- ".word\t1b,3b\n\t" \
- ".previous" \
- :"=r" (__gu_err), "=r" (__gu_val) \
- :"o" (__m(__gu_addr)), "i" (-EFAULT)); \
+ "1: " insn " %1, %3 \n" \
+ "2: \n" \
+ " .section .fixup,\"ax\" \n" \
+ "3: li %0, %4 \n" \
+ " j 2b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " "__UA_ADDR "\t1b, 3b \n" \
+ " .previous \n" \
+ : "=r" (__gu_err), "=r" (__gu_val) \
+ : "0" (__gu_err), "o" (__m(__gu_addr)), "i" (-EFAULT)); \
})
/*
* Get a long long 64 using 32 bit registers.
*/
-#define __get_user_asm_ll32 \
+#define __get_user_asm_ll32(__gu_err) \
({ \
-__asm__ __volatile__( \
- "1:\tlw\t%1,%2\n" \
- "2:\tlw\t%D1,%3\n\t" \
- "move\t%0,$0\n" \
- "3:\t.section\t.fixup,\"ax\"\n" \
- "4:\tli\t%0,%4\n\t" \
- "move\t%1,$0\n\t" \
- "move\t%D1,$0\n\t" \
- "j\t3b\n\t" \
- ".previous\n\t" \
- ".section\t__ex_table,\"a\"\n\t" \
- ".word\t1b,4b\n\t" \
- ".word\t2b,4b\n\t" \
- ".previous" \
- :"=r" (__gu_err), "=&r" (__gu_val) \
- :"o" (__m(__gu_addr)), "o" (__m(__gu_addr + 4)), \
+ __asm__ __volatile__( \
+ "1: lw %1,%2 \n" \
+ "2: lw %D1,%3 \n" \
+ " move %0,$0 \n" \
+ "3: .section .fixup,\"ax\" \n" \
+ "4: li %0,%4 \n" \
+ " move %1,$0 \n" \
+ " move %D1,$0 \n" \
+ " j 3b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " " __UA_ADDR " 1b,4b \n" \
+ " " __UA_ADDR " 2b,4b \n" \
+ " .previous \n" \
+ : "=r" (__gu_err), "=&r" (__gu_val) \
+ : "o" (__m(__gu_addr)), "o" (__m(__gu_addr + 4)), \
"i" (-EFAULT)); \
})
@@ -282,84 +312,81 @@
* for 32 bit mode and old iron.
*/
#ifdef __mips64
-#define __PUT_USER_DW __put_user_asm("sd")
+#define __PUT_USER_DW(__pu_val) __put_user_asm("sd", __pu_val)
#else
-#define __PUT_USER_DW __put_user_asm_ll32
+#define __PUT_USER_DW(__pu_val) __put_user_asm_ll32(__pu_val)
#endif
#define __put_user_nocheck(x,ptr,size) \
({ \
- long __pu_err; \
+ long __pu_err = 0; \
__typeof__(*(ptr)) __pu_val; \
long __pu_addr; \
__pu_val = (x); \
__pu_addr = (long) (ptr); \
- __asm__("":"=r" (__pu_err)); \
switch (size) { \
- case 1: __put_user_asm("sb"); break; \
- case 2: __put_user_asm("sh"); break; \
- case 4: __put_user_asm("sw"); break; \
- case 8: __PUT_USER_DW; break; \
- default: __put_user_unknown(); break; \
+ case 1: __put_user_asm("sb", __pu_val); break; \
+ case 2: __put_user_asm("sh", __pu_val); break; \
+ case 4: __put_user_asm("sw", __pu_val); break; \
+ case 8: __PUT_USER_DW(__pu_val); break; \
+ default: __put_user_unknown(); break; \
} \
__pu_err; \
})
#define __put_user_check(x,ptr,size) \
({ \
- long __pu_err; \
+ long __pu_err = 0; \
__typeof__(*(ptr)) __pu_val; \
long __pu_addr; \
__pu_val = (x); \
__pu_addr = (long) (ptr); \
- __asm__("":"=r" (__pu_err)); \
if (access_ok(VERIFY_WRITE, __pu_addr, size)) { \
switch (size) { \
- case 1: __put_user_asm("sb"); break; \
- case 2: __put_user_asm("sh"); break; \
- case 4: __put_user_asm("sw"); break; \
- case 8: __PUT_USER_DW; break; \
+ case 1: __put_user_asm("sb", __pu_val); break; \
+ case 2: __put_user_asm("sh", __pu_val); break; \
+ case 4: __put_user_asm("sw", __pu_val); break; \
+ case 8: __PUT_USER_DW(__pu_val); break; \
default: __put_user_unknown(); break; \
} \
} \
__pu_err; \
})
-#define __put_user_asm(insn) \
+#define __put_user_asm(insn, __pu_val) \
({ \
__asm__ __volatile__( \
- "1:\t" insn "\t%z1, %2\t\t\t# __put_user_asm\n\t" \
- "move\t%0, $0\n" \
- "2:\n\t" \
- ".section\t.fixup,\"ax\"\n" \
- "3:\tli\t%0, %3\n\t" \
- "j\t2b\n\t" \
- ".previous\n\t" \
- ".section\t__ex_table,\"a\"\n\t" \
- ".word\t1b, 3b\n\t" \
- ".previous" \
+ "1: " insn " %z1, %2 # __put_user_asm\n" \
+ "2: \n" \
+ " .section .fixup,\"ax\" \n" \
+ "3: li %0,%3 \n" \
+ " j 2b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " " __UA_ADDR " 1b, 3b \n" \
+ " .previous \n" \
:"=r" (__pu_err) \
:"Jr" (__pu_val), "o" (__m(__pu_addr)), "i" (-EFAULT)); \
})
-#define __put_user_asm_ll32 \
+#define __put_user_asm_ll32(__pu_val) \
({ \
-__asm__ __volatile__( \
- "1:\tsw\t%1, %2\t\t\t# __put_user_asm_ll32\n\t" \
- "2:\tsw\t%D1, %3\n" \
- "move\t%0, $0\n" \
- "3:\n\t" \
- ".section\t.fixup,\"ax\"\n" \
- "4:\tli\t%0, %4\n\t" \
- "j\t3b\n\t" \
- ".previous\n\t" \
- ".section\t__ex_table,\"a\"\n\t" \
- ".word\t1b,4b\n\t" \
- ".word\t2b,4b\n\t" \
- ".previous" \
+ __asm__ __volatile__( \
+ "1: sw %1, %2 # __put_user_asm_ll32 \n" \
+ "2: sw %D1, %3 \n" \
+ " move %0, $0 \n" \
+ "3: \n" \
+ " .section .fixup,\"ax\" \n" \
+ "4: li %0, %4 \n" \
+ " j 3b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " " __UA_ADDR " 1b, 4b \n" \
+ " " __UA_ADDR " 2b, 4b \n" \
+ " .previous" \
:"=r" (__pu_err) \
- :"r" (__pu_val), "o" (__m(__pu_addr)), "o" (__m(__pu_addr + 4)),\
- "i" (-EFAULT)); \
+ :"r" (__pu_val), "o" (__m(__pu_addr)), \
+ "o" (__m(__pu_addr + 4)), "i" (-EFAULT)); \
})
extern void __put_user_unknown(void);
@@ -371,7 +398,7 @@
#ifdef MODULE
#define __MODULE_JAL(destination) \
".set\tnoat\n\t" \
- "la\t$1, " #destination "\n\t" \
+ __UA_LA "\t$1, " #destination "\n\t" \
"jalr\t$1\n\t" \
".set\tat\n\t"
#else
@@ -426,6 +453,9 @@
__cu_len; \
})
+#define __copy_to_user_inatomic __copy_to_user
+#define __copy_from_user_inatomic __copy_from_user
+
/*
* copy_to_user: - Copy a block of data into user space.
* @to: Destination address, in user space.
@@ -467,9 +497,10 @@
".set\tnoreorder\n\t" \
__MODULE_JAL(__copy_user) \
".set\tnoat\n\t" \
- "addu\t$1, %1, %2\n\t" \
+ __UA_ADDU "\t$1, %1, %2\n\t" \
".set\tat\n\t" \
".set\treorder\n\t" \
+ "move\t%0, $6" /* XXX */ \
: "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
: \
: "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31", \
@@ -538,6 +569,24 @@
__cu_len; \
})
+#define __copy_in_user(to, from, n) __copy_from_user(to, from, n)
+
+#define copy_in_user(to,from,n) \
+({ \
+ void *__cu_to; \
+ const void *__cu_from; \
+ long __cu_len; \
+ \
+ __cu_to = (to); \
+ __cu_from = (from); \
+ __cu_len = (n); \
+ if (likely(access_ok(VERIFY_READ, __cu_from, __cu_len) && \
+ access_ok(VERIFY_WRITE, __cu_to, __cu_len))) \
+ __cu_len = __invoke_copy_from_user(__cu_to, __cu_from, \
+ __cu_len); \
+ __cu_len; \
+})
+
/*
* __clear_user: - Zero a block of memory in user space, with less checking.
* @to: Destination address, in user space.
@@ -562,7 +611,7 @@
"move\t%0, $6"
: "=r" (res)
: "r" (addr), "r" (size)
- : "$4", "$5", "$6", "$8", "$9", "$31");
+ : "$4", "$5", "$6", __UA_t0, __UA_t1, "$31");
return res;
}
@@ -610,7 +659,7 @@
"move\t%0, $2"
: "=r" (res)
: "r" (__to), "r" (__from), "r" (__len)
- : "$2", "$3", "$4", "$5", "$6", "$8", "$31", "memory");
+ : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
return res;
}
@@ -646,7 +695,7 @@
"move\t%0, $2"
: "=r" (res)
: "r" (__to), "r" (__from), "r" (__len)
- : "$2", "$3", "$4", "$5", "$6", "$8", "$31", "memory");
+ : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
return res;
}
@@ -662,7 +711,7 @@
"move\t%0, $2"
: "=r" (res)
: "r" (s)
- : "$2", "$4", "$8", "$31");
+ : "$2", "$4", __UA_t0, "$31");
return res;
}
@@ -691,7 +740,24 @@
"move\t%0, $2"
: "=r" (res)
: "r" (s)
- : "$2", "$4", "$8", "$31");
+ : "$2", "$4", __UA_t0, "$31");
+
+ return res;
+}
+
+/* Returns: 0 if bad, string length+1 (memory size) of string if ok */
+static inline long __strnlen_user(const char *s, long n)
+{
+ long res;
+
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ "move\t$5, %2\n\t"
+ __MODULE_JAL(__strnlen_user_nocheck_asm)
+ "move\t%0, $2"
+ : "=r" (res)
+ : "r" (s), "r" (n)
+ : "$2", "$4", "$5", __UA_t0, "$31");
return res;
}
@@ -699,13 +765,16 @@
/*
* strlen_user: - Get the size of a string in user space.
* @str: The string to measure.
- * @n: The maximum valid length
+ *
+ * Context: User context only. This function may sleep.
*
* Get the size of a NUL-terminated string in user space.
*
* Returns the size of the string INCLUDING the terminating NUL.
* On exception, returns 0.
- * If the string is too long, returns a value greater than @n.
+ *
+ * If there is a limit on the length of a valid string, you may wish to
+ * consider using strnlen_user() instead.
*/
static inline long strnlen_user(const char *s, long n)
{
@@ -718,7 +787,7 @@
"move\t%0, $2"
: "=r" (res)
: "r" (s), "r" (n)
- : "$2", "$4", "$5", "$8", "$31");
+ : "$2", "$4", "$5", __UA_t0, "$31");
return res;
}
Index: include/asm-mips64/uaccess.h
===================================================================
RCS file: /home/cvs/linux/include/asm-mips64/Attic/uaccess.h,v
retrieving revision 1.13.2.4
diff -u -r1.13.2.4 uaccess.h
--- include/asm-mips64/uaccess.h 14 Sep 2003 20:55:20 -0000 1.13.2.4
+++ include/asm-mips64/uaccess.h 20 Sep 2004 17:04:42 -0000
@@ -3,19 +3,17 @@
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
- * Copyright (C) 1996, 1997, 1998, 1999, 2000, 03 by Ralf Baechle
+ * Copyright (C) 1996, 1997, 1998, 1999, 2000, 03, 04 by Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
*/
#ifndef _ASM_UACCESS_H
#define _ASM_UACCESS_H
+#include <linux/config.h>
#include <linux/compiler.h>
#include <linux/errno.h>
#include <linux/sched.h>
-#define STR(x) __STR(x)
-#define __STR(x) #x
-
/*
* The fs value determines whether argument validity checking should be
* performed or not. If get_fs() == USER_DS, checking is performed, with
@@ -23,15 +21,47 @@
*
* For historical reasons, these macros are grossly misnamed.
*/
+#ifdef CONFIG_MIPS32
+
+#define __UA_LIMIT 0x80000000UL
+
+#define __UA_ADDR ".word"
+#define __UA_LA "la"
+#define __UA_ADDU "addu"
+#define __UA_t0 "$8"
+#define __UA_t1 "$9"
+
+#endif /* CONFIG_MIPS32 */
+
+#ifdef CONFIG_MIPS64
+
+#define __UA_LIMIT (- TASK_SIZE)
+
+#define __UA_ADDR ".dword"
+#define __UA_LA "dla"
+#define __UA_ADDU "daddu"
+#define __UA_t0 "$12"
+#define __UA_t1 "$13"
+
+#endif /* CONFIG_MIPS64 */
+
+/*
+ * USER_DS is a bitmask that has the bits set that may not be set in a valid
+ * userspace address. Note that we limit 32-bit userspace to 0x7fff8000 but
+ * the arithmetic we're doing only works if the limit is a power of two, so
+ * we use 0x80000000 here on 32-bit kernels. If a process passes an invalid
+ * address in this range it's the process's problem, not ours :-)
+ */
+
#define KERNEL_DS ((mm_segment_t) { 0UL })
-#define USER_DS ((mm_segment_t) { -TASK_SIZE })
+#define USER_DS ((mm_segment_t) { __UA_LIMIT })
#define VERIFY_READ 0
#define VERIFY_WRITE 1
-#define get_fs() (current->thread.current_ds)
#define get_ds() (KERNEL_DS)
-#define set_fs(x) (current->thread.current_ds=(x))
+#define get_fs() (current->thread.current_ds)
+#define set_fs(x) (current->thread.current_ds = (x))
#define segment_eq(a,b) ((a).seg == (b).seg)
@@ -45,14 +75,12 @@
* - AND "size" doesn't have any high-bits set
* - AND "addr+size" doesn't have any high-bits set
* - OR we are in kernel mode.
+ *
+ * __ua_size() is a trick to avoid runtime checking of positive constant
+ * sizes; for those we already know at compile time that the size is ok.
*/
#define __ua_size(size) \
- ((__builtin_constant_p(size) && (size)) > 0 ? 0 : (size))
-
-#define __access_ok(addr, size, mask) \
- (((mask) & ((addr) | ((addr) + (size)) | __ua_size(size))) == 0)
-
-#define __access_mask get_fs().seg
+ ((__builtin_constant_p(size) && (signed long) (size) > 0) ? 0 : (size))
/*
* access_ok: - Checks if a user space pointer is valid
@@ -73,8 +101,14 @@
* checks that the pointer is in the user space range - after calling
* this function, memory access functions may still return -EFAULT.
*/
+
+#define __access_mask get_fs().seg
+
+#define __access_ok(addr, size, mask) \
+ (((signed long)((mask) & ((addr) | ((addr) + (size)) | __ua_size(size)))) == 0)
+
#define access_ok(type, addr, size) \
- likely(__access_ok((unsigned long)(addr), (size), __access_mask))
+ likely(__access_ok((unsigned long)(addr), (size),__access_mask))
/*
* verify_area: - Obsolete, use access_ok()
@@ -185,119 +219,176 @@
struct __large_struct { unsigned long buf[100]; };
#define __m(x) (*(struct __large_struct *)(x))
+/*
+ * Yuck. We need two variants, one for 64bit operation and one
+ * for 32 bit mode and old iron.
+ */
+#ifdef __mips64
+#define __GET_USER_DW(__gu_err) __get_user_asm("ld", __gu_err)
+#else
+#define __GET_USER_DW(__gu_err) __get_user_asm_ll32(__gu_err)
+#endif
+
#define __get_user_nocheck(x,ptr,size) \
({ \
- long __gu_err; \
- __typeof(*(ptr)) __gu_val; \
+ long __gu_err = 0; \
+ __typeof(*(ptr)) __gu_val = 0; \
long __gu_addr; \
- __asm__("":"=r" (__gu_val)); \
__gu_addr = (long) (ptr); \
- __asm__("":"=r" (__gu_err)); \
switch (size) { \
- case 1: __get_user_asm("lb"); break; \
- case 2: __get_user_asm("lh"); break; \
- case 4: __get_user_asm("lw"); break; \
- case 8: __get_user_asm("ld"); break; \
- default: __get_user_unknown(); break; \
- } x = (__typeof__(*(ptr))) __gu_val; \
+ case 1: __get_user_asm("lb", __gu_err); break; \
+ case 2: __get_user_asm("lh", __gu_err); break; \
+ case 4: __get_user_asm("lw", __gu_err); break; \
+ case 8: __GET_USER_DW(__gu_err); break; \
+ default: __get_user_unknown(); break; \
+ } \
+ x = (__typeof__(*(ptr))) __gu_val; \
__gu_err; \
})
#define __get_user_check(x,ptr,size) \
({ \
- long __gu_err; \
- __typeof__(*(ptr)) __gu_val; \
+ long __gu_err = 0; \
+ __typeof__(*(ptr)) __gu_val = 0; \
long __gu_addr; \
- __asm__("":"=r" (__gu_val)); \
__gu_addr = (long) (ptr); \
- __asm__("":"=r" (__gu_err)); \
- if (access_ok(VERIFY_READ, __gu_addr, size)) { \
+ if (access_ok(VERIFY_READ,__gu_addr,size)) { \
switch (size) { \
- case 1: __get_user_asm("lb"); break; \
- case 2: __get_user_asm("lh"); break; \
- case 4: __get_user_asm("lw"); break; \
- case 8: __get_user_asm("ld"); break; \
+ case 1: __get_user_asm("lb", __gu_err); break; \
+ case 2: __get_user_asm("lh", __gu_err); break; \
+ case 4: __get_user_asm("lw", __gu_err); break; \
+ case 8: __GET_USER_DW(__gu_err); break; \
default: __get_user_unknown(); break; \
} \
- } x = (__typeof__(*(ptr))) __gu_val; \
- __gu_err; \
+ } \
+ x = (__typeof__(*(ptr))) __gu_val; \
+ __gu_err; \
})
-#define __get_user_asm(insn) \
+#define __get_user_asm(insn,__gu_err) \
({ \
__asm__ __volatile__( \
- "1:\t" insn "\t%1,%2\n\t" \
- "move\t%0,$0\n" \
- "2:\n\t" \
- ".section\t.fixup,\"ax\"\n" \
- "3:\tli\t%0,%3\n\t" \
- "move\t%1,$0\n\t" \
- "j\t2b\n\t" \
- ".previous\n\t" \
- ".section\t__ex_table,\"a\"\n\t" \
- ".dword\t1b,3b\n\t" \
- ".previous" \
- :"=r" (__gu_err), "=r" (__gu_val) \
- :"o" (__m(__gu_addr)), "i" (-EFAULT)); \
+ "1: " insn " %1, %3 \n" \
+ "2: \n" \
+ " .section .fixup,\"ax\" \n" \
+ "3: li %0, %4 \n" \
+ " j 2b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " "__UA_ADDR "\t1b, 3b \n" \
+ " .previous \n" \
+ : "=r" (__gu_err), "=r" (__gu_val) \
+ : "0" (__gu_err), "o" (__m(__gu_addr)), "i" (-EFAULT)); \
+})
+
+/*
+ * Get a long long 64 using 32 bit registers.
+ */
+#define __get_user_asm_ll32(__gu_err) \
+({ \
+ __asm__ __volatile__( \
+ "1: lw %1,%2 \n" \
+ "2: lw %D1,%3 \n" \
+ " move %0,$0 \n" \
+ "3: .section .fixup,\"ax\" \n" \
+ "4: li %0,%4 \n" \
+ " move %1,$0 \n" \
+ " move %D1,$0 \n" \
+ " j 3b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " " __UA_ADDR " 1b,4b \n" \
+ " " __UA_ADDR " 2b,4b \n" \
+ " .previous \n" \
+ : "=r" (__gu_err), "=&r" (__gu_val) \
+ : "o" (__m(__gu_addr)), "o" (__m(__gu_addr + 4)), \
+ "i" (-EFAULT)); \
})
extern void __get_user_unknown(void);
+/*
+ * Yuck. We need two variants, one for 64bit operation and one
+ * for 32 bit mode and old iron.
+ */
+#ifdef __mips64
+#define __PUT_USER_DW(__pu_val) __put_user_asm("sd", __pu_val)
+#else
+#define __PUT_USER_DW(__pu_val) __put_user_asm_ll32(__pu_val)
+#endif
+
#define __put_user_nocheck(x,ptr,size) \
({ \
- long __pu_err; \
+ long __pu_err = 0; \
__typeof__(*(ptr)) __pu_val; \
long __pu_addr; \
__pu_val = (x); \
__pu_addr = (long) (ptr); \
- __asm__("":"=r" (__pu_err)); \
switch (size) { \
- case 1: __put_user_asm("sb"); break; \
- case 2: __put_user_asm("sh"); break; \
- case 4: __put_user_asm("sw"); break; \
- case 8: __put_user_asm("sd"); break; \
- default: __put_user_unknown(); break; \
+ case 1: __put_user_asm("sb", __pu_val); break; \
+ case 2: __put_user_asm("sh", __pu_val); break; \
+ case 4: __put_user_asm("sw", __pu_val); break; \
+ case 8: __PUT_USER_DW(__pu_val); break; \
+ default: __put_user_unknown(); break; \
} \
__pu_err; \
})
#define __put_user_check(x,ptr,size) \
({ \
- long __pu_err; \
+ long __pu_err = 0; \
__typeof__(*(ptr)) __pu_val; \
long __pu_addr; \
__pu_val = (x); \
__pu_addr = (long) (ptr); \
- __asm__("":"=r" (__pu_err)); \
if (access_ok(VERIFY_WRITE, __pu_addr, size)) { \
switch (size) { \
- case 1: __put_user_asm("sb"); break; \
- case 2: __put_user_asm("sh"); break; \
- case 4: __put_user_asm("sw"); break; \
- case 8: __put_user_asm("sd"); break; \
+ case 1: __put_user_asm("sb", __pu_val); break; \
+ case 2: __put_user_asm("sh", __pu_val); break; \
+ case 4: __put_user_asm("sw", __pu_val); break; \
+ case 8: __PUT_USER_DW(__pu_val); break; \
default: __put_user_unknown(); break; \
} \
} \
__pu_err; \
})
-#define __put_user_asm(insn) \
+#define __put_user_asm(insn, __pu_val) \
({ \
__asm__ __volatile__( \
- "1:\t" insn "\t%z1, %2\t\t\t# __put_user_asm\n\t" \
- "move\t%0, $0\n" \
- "2:\n\t" \
- ".section\t.fixup,\"ax\"\n" \
- "3:\tli\t%0, %3\n\t" \
- "j\t2b\n\t" \
- ".previous\n\t" \
- ".section\t__ex_table,\"a\"\n\t" \
- ".dword\t1b, 3b\n\t" \
- ".previous" \
+ "1: " insn " %z1, %2 # __put_user_asm\n" \
+ "2: \n" \
+ " .section .fixup,\"ax\" \n" \
+ "3: li %0,%3 \n" \
+ " j 2b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " " __UA_ADDR " 1b, 3b \n" \
+ " .previous \n" \
:"=r" (__pu_err) \
:"Jr" (__pu_val), "o" (__m(__pu_addr)), "i" (-EFAULT)); \
})
+#define __put_user_asm_ll32(__pu_val) \
+({ \
+ __asm__ __volatile__( \
+ "1: sw %1, %2 # __put_user_asm_ll32 \n" \
+ "2: sw %D1, %3 \n" \
+ " move %0, $0 \n" \
+ "3: \n" \
+ " .section .fixup,\"ax\" \n" \
+ "4: li %0, %4 \n" \
+ " j 3b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " " __UA_ADDR " 1b, 4b \n" \
+ " " __UA_ADDR " 2b, 4b \n" \
+ " .previous" \
+ :"=r" (__pu_err) \
+ :"r" (__pu_val), "o" (__m(__pu_addr)), \
+ "o" (__m(__pu_addr + 4)), "i" (-EFAULT)); \
+})
+
extern void __put_user_unknown(void);
/*
@@ -307,7 +398,7 @@
#ifdef MODULE
#define __MODULE_JAL(destination) \
".set\tnoat\n\t" \
- "dla\t$1, " #destination "\n\t" \
+ __UA_LA "\t$1, " #destination "\n\t" \
"jalr\t$1\n\t" \
".set\tat\n\t"
#else
@@ -362,6 +453,9 @@
__cu_len; \
})
+#define __copy_to_user_inatomic __copy_to_user
+#define __copy_from_user_inatomic __copy_from_user
+
/*
* copy_to_user: - Copy a block of data into user space.
* @to: Destination address, in user space.
@@ -403,10 +497,10 @@
".set\tnoreorder\n\t" \
__MODULE_JAL(__copy_user) \
".set\tnoat\n\t" \
- "daddu\t$1, %1, %2\n\t" \
+ __UA_ADDU "\t$1, %1, %2\n\t" \
".set\tat\n\t" \
".set\treorder\n\t" \
- "move\t%0, $6" \
+ "move\t%0, $6" /* XXX */ \
: "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
: \
: "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31", \
@@ -475,6 +569,24 @@
__cu_len; \
})
+#define __copy_in_user(to, from, n) __copy_from_user(to, from, n)
+
+#define copy_in_user(to,from,n) \
+({ \
+ void *__cu_to; \
+ const void *__cu_from; \
+ long __cu_len; \
+ \
+ __cu_to = (to); \
+ __cu_from = (from); \
+ __cu_len = (n); \
+ if (likely(access_ok(VERIFY_READ, __cu_from, __cu_len) && \
+ access_ok(VERIFY_WRITE, __cu_to, __cu_len))) \
+ __cu_len = __invoke_copy_from_user(__cu_to, __cu_from, \
+ __cu_len); \
+ __cu_len; \
+})
+
/*
* __clear_user: - Zero a block of memory in user space, with less checking.
* @to: Destination address, in user space.
@@ -499,7 +611,7 @@
"move\t%0, $6"
: "=r" (res)
: "r" (addr), "r" (size)
- : "$4", "$5", "$6", "$8", "$9", "$31");
+ : "$4", "$5", "$6", __UA_t0, __UA_t1, "$31");
return res;
}
@@ -547,7 +659,7 @@
"move\t%0, $2"
: "=r" (res)
: "r" (__to), "r" (__from), "r" (__len)
- : "$2", "$3", "$4", "$5", "$6", "$8", "$31", "memory");
+ : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
return res;
}
@@ -583,7 +695,7 @@
"move\t%0, $2"
: "=r" (res)
: "r" (__to), "r" (__from), "r" (__len)
- : "$2", "$3", "$4", "$5", "$6", "$8", "$31", "memory");
+ : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
return res;
}
@@ -599,7 +711,7 @@
"move\t%0, $2"
: "=r" (res)
: "r" (s)
- : "$2", "$4", "$8", "$31");
+ : "$2", "$4", __UA_t0, "$31");
return res;
}
@@ -628,7 +740,24 @@
"move\t%0, $2"
: "=r" (res)
: "r" (s)
- : "$2", "$4", "$8", "$31");
+ : "$2", "$4", __UA_t0, "$31");
+
+ return res;
+}
+
+/* Returns: 0 if bad, string length+1 (memory size) of string if ok */
+static inline long __strnlen_user(const char *s, long n)
+{
+ long res;
+
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ "move\t$5, %2\n\t"
+ __MODULE_JAL(__strnlen_user_nocheck_asm)
+ "move\t%0, $2"
+ : "=r" (res)
+ : "r" (s), "r" (n)
+ : "$2", "$4", "$5", __UA_t0, "$31");
return res;
}
@@ -636,13 +765,16 @@
/*
* strlen_user: - Get the size of a string in user space.
* @str: The string to measure.
- * @n: The maximum valid length
+ *
+ * Context: User context only. This function may sleep.
*
* Get the size of a NUL-terminated string in user space.
*
* Returns the size of the string INCLUDING the terminating NUL.
* On exception, returns 0.
- * If the string is too long, returns a value greater than @n.
+ *
+ * If there is a limit on the length of a valid string, you may wish to
+ * consider using strnlen_user() instead.
*/
static inline long strnlen_user(const char *s, long n)
{
@@ -655,7 +787,7 @@
"move\t%0, $2"
: "=r" (res)
: "r" (s), "r" (n)
- : "$2", "$4", "$5", "$8", "$31");
+ : "$2", "$4", "$5", __UA_t0, "$31");
return res;
}
next prev parent reply other threads:[~2004-09-20 17:10 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-08-31 16:22 gcc 3.3.4/3.4.1 and get_user Atsushi Nemoto
2004-09-01 8:51 ` Richard Sandiford
2004-09-01 15:14 ` Atsushi Nemoto
2004-09-01 15:16 ` Atsushi Nemoto
2004-09-20 8:59 ` Richard Sandiford
2004-09-20 14:18 ` Atsushi Nemoto
2004-09-20 15:40 ` Ralf Baechle
2004-09-20 17:10 ` Ralf Baechle [this message]
2004-09-24 7:39 ` Atsushi Nemoto
2004-11-04 6:37 ` Atsushi Nemoto
2004-11-12 13:44 ` Ralf Baechle
2004-11-16 3:15 ` Atsushi Nemoto
2004-09-24 3:18 ` Atsushi Nemoto
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