From: Catalin Marinas <catalin.marinas@arm.com>
To: linux-kernel@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>, Will Deacon <will.deacon@arm.com>,
Marc Zyngier <marc.zyngier@arm.com>
Subject: [PATCH 26/36] AArch64: User access library functions
Date: Fri, 6 Jul 2012 22:06:07 +0100 [thread overview]
Message-ID: <1341608777-12982-27-git-send-email-catalin.marinas@arm.com> (raw)
In-Reply-To: <1341608777-12982-1-git-send-email-catalin.marinas@arm.com>
This patch add support for various user access functions. These
functions use the standard LDR/STR instructions and not the LDRT/STRT
variants in order to allow kernel addresses (after set_fs(KERNEL_DS)).
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
---
arch/aarch64/include/asm/uaccess.h | 378 ++++++++++++++++++++++++++++++++++
arch/aarch64/lib/clear_user.S | 59 ++++++
arch/aarch64/lib/copy_from_user.S | 67 ++++++
arch/aarch64/lib/copy_in_user.S | 64 ++++++
arch/aarch64/lib/copy_to_user.S | 62 ++++++
arch/aarch64/lib/getuser.S | 76 +++++++
arch/aarch64/lib/putuser.S | 74 +++++++
arch/aarch64/lib/strncpy_from_user.S | 51 +++++
arch/aarch64/lib/strnlen_user.S | 48 +++++
9 files changed, 879 insertions(+), 0 deletions(-)
create mode 100644 arch/aarch64/include/asm/uaccess.h
create mode 100644 arch/aarch64/lib/clear_user.S
create mode 100644 arch/aarch64/lib/copy_from_user.S
create mode 100644 arch/aarch64/lib/copy_in_user.S
create mode 100644 arch/aarch64/lib/copy_to_user.S
create mode 100644 arch/aarch64/lib/getuser.S
create mode 100644 arch/aarch64/lib/putuser.S
create mode 100644 arch/aarch64/lib/strncpy_from_user.S
create mode 100644 arch/aarch64/lib/strnlen_user.S
diff --git a/arch/aarch64/include/asm/uaccess.h b/arch/aarch64/include/asm/uaccess.h
new file mode 100644
index 0000000..e6dbf11
--- /dev/null
+++ b/arch/aarch64/include/asm/uaccess.h
@@ -0,0 +1,378 @@
+/*
+ * Based on arch/arm/include/asm/uaccess.h
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+#ifndef __ASM_UACCESS_H
+#define __ASM_UACCESS_H
+
+/*
+ * User space memory access functions
+ */
+#include <linux/string.h>
+#include <linux/thread_info.h>
+
+#include <asm/ptrace.h>
+#include <asm/errno.h>
+#include <asm/memory.h>
+#include <asm/compiler.h>
+
+#define VERIFY_READ 0
+#define VERIFY_WRITE 1
+
+/*
+ * The exception table consists of pairs of addresses: the first is the
+ * address of an instruction that is allowed to fault, and the second is
+ * the address at which the program should continue. No registers are
+ * modified, so it is entirely up to the continuation code to figure out
+ * what to do.
+ *
+ * All the routines below use bits of fixup code that are out of line
+ * with the main instruction path. This means when everything is well,
+ * we don't even have to jump over them. Further, they do not intrude
+ * on our cache or tlb entries.
+ */
+
+struct exception_table_entry
+{
+ unsigned long insn, fixup;
+};
+
+extern int fixup_exception(struct pt_regs *regs);
+
+/*
+ * These two are intentionally not defined anywhere - if the kernel
+ * code generates any references to them, that's a bug.
+ */
+extern long __get_user_bad(void);
+extern long __put_user_bad(void);
+
+#define KERNEL_DS (-1UL)
+#define get_ds() (KERNEL_DS)
+
+#define USER_DS TASK_SIZE_64
+#define get_fs() (current_thread_info()->addr_limit)
+
+static inline void set_fs(mm_segment_t fs)
+{
+ current_thread_info()->addr_limit = fs;
+}
+
+#define segment_eq(a,b) ((a) == (b))
+
+/*
+ * Return 1 if addr < current->addr_limit, 0 otherwise.
+ */
+#define __addr_ok(addr) \
+({ \
+ unsigned long flag; \
+ asm("cmp %1, %0; cset %0, lo" \
+ : "=&r" (flag) \
+ : "r" (addr), "0" (current_thread_info()->addr_limit) \
+ : "cc"); \
+ flag; \
+})
+
+/*
+ * Test whether a block of memory is a valid user space address.
+ * Returns 1 if the range is valid, 0 otherwise.
+ *
+ * This is equivalent to the following test:
+ * (u65)addr + (u65)size < (u65)current->addr_limit
+ *
+ * This needs 65-bit arithmetic.
+ */
+#define __range_ok(addr,size) \
+({ \
+ unsigned long flag, roksum; \
+ __chk_user_ptr(addr); \
+ asm("adds %1, %1, %3; ccmp %1, %4, #2, cc; cset %0, cc" \
+ : "=&r" (flag), "=&r" (roksum) \
+ : "1" (addr), "Ir" (size), \
+ "r" (current_thread_info()->addr_limit) \
+ : "cc"); \
+ flag; \
+})
+
+/*
+ * Single-value transfer routines. They automatically use the right
+ * size if we just have the right pointer type. Note that the functions
+ * which read from user space (*get_*) need to take care not to leak
+ * kernel data even if the calling code is buggy and fails to check
+ * the return value. This means zeroing out the destination variable
+ * or buffer on error. Normally this is done out of line by the
+ * fixup code, but there are a few places where it intrudes on the
+ * main code path. When we only write to user space, there is no
+ * problem.
+ */
+extern long __get_user_1(void *);
+extern long __get_user_2(void *);
+extern long __get_user_4(void *);
+extern long __get_user_8(void *);
+
+#define __get_user_x(__r2,__p,__e,__s,__i...) \
+ asm volatile( \
+ __asmeq("%0", "x0") __asmeq("%1", "x2") \
+ "bl __get_user_" #__s \
+ : "=&r" (__e), "=r" (__r2) \
+ : "0" (__p) \
+ : __i, "cc")
+
+#define get_user(x,p) \
+ ({ \
+ register const typeof(*(p)) __user *__p asm("x0") = (p);\
+ register unsigned long __r2 asm("x2"); \
+ register long __e asm("x0"); \
+ switch (sizeof(*(__p))) { \
+ case 1: \
+ __get_user_x(__r2, __p, __e, 1, "x30"); \
+ break; \
+ case 2: \
+ __get_user_x(__r2, __p, __e, 2, "x3", "x30"); \
+ break; \
+ case 4: \
+ __get_user_x(__r2, __p, __e, 4, "x30"); \
+ break; \
+ case 8: \
+ __get_user_x(__r2, __p, __e, 8, "x30"); \
+ break; \
+ default: __e = __get_user_bad(); break; \
+ } \
+ x = (typeof(*(p))) __r2; \
+ __e; \
+ })
+
+#define __get_user_unaligned __get_user
+
+extern long __put_user_1(void *, unsigned long);
+extern long __put_user_2(void *, unsigned long);
+extern long __put_user_4(void *, unsigned long);
+extern long __put_user_8(void *, unsigned long);
+
+#define __put_user_x(__r2,__p,__e,__s) \
+ asm volatile( \
+ __asmeq("%0", "x0") __asmeq("%2", "x2") \
+ "bl __put_user_" #__s \
+ : "=&r" (__e) \
+ : "0" (__p), "r" (__r2) \
+ : "x8", "x30", "cc")
+
+#define put_user(x,p) \
+ ({ \
+ register const typeof(*(p)) __r2 asm("x2") = (x); \
+ register const typeof(*(p)) __user *__p asm("x0") = (p);\
+ register long __e asm("x0"); \
+ switch (sizeof(*(__p))) { \
+ case 1: \
+ __put_user_x(__r2, __p, __e, 1); \
+ break; \
+ case 2: \
+ __put_user_x(__r2, __p, __e, 2); \
+ break; \
+ case 4: \
+ __put_user_x(__r2, __p, __e, 4); \
+ break; \
+ case 8: \
+ __put_user_x(__r2, __p, __e, 8); \
+ break; \
+ default: __e = __put_user_bad(); break; \
+ } \
+ __e; \
+ })
+
+#define __put_user_unaligned __put_user
+
+#define access_ok(type,addr,size) __range_ok(addr,size)
+
+/*
+ * The "__xxx" versions of the user access functions do not verify the
+ * address space - it must have been done previously with a separate
+ * "access_ok()" call.
+ *
+ * The "xxx_error" versions set the third argument to EFAULT if an
+ * error occurs, and leave it unchanged on success. Note that these
+ * versions are void (ie, don't return a value as such).
+ */
+#define __get_user(x,ptr) \
+({ \
+ long __gu_err = 0; \
+ __get_user_err((x),(ptr),__gu_err); \
+ __gu_err; \
+})
+
+#define __get_user_error(x,ptr,err) \
+({ \
+ __get_user_err((x),(ptr),err); \
+ (void) 0; \
+})
+
+#define __get_user_err(x,ptr,err) \
+do { \
+ unsigned long __gu_addr = (unsigned long)(ptr); \
+ unsigned long __gu_val; \
+ __chk_user_ptr(ptr); \
+ switch (sizeof(*(ptr))) { \
+ case 1: \
+ __get_user_asm("ldrb", "%w", __gu_val, __gu_addr, err); \
+ break; \
+ case 2: \
+ __get_user_asm("ldrh", "%w", __gu_val, __gu_addr, err); \
+ break; \
+ case 4: \
+ __get_user_asm("ldr", "%w", __gu_val, __gu_addr, err); \
+ break; \
+ case 8: \
+ __get_user_asm("ldr", "%", __gu_val, __gu_addr, err); \
+ break; \
+ default: \
+ (__gu_val) = __get_user_bad(); \
+ } \
+ (x) = (__typeof__(*(ptr)))__gu_val; \
+} while (0)
+
+#define __get_user_asm(instr, reg, x, addr, err) \
+ asm volatile( \
+ "1: " instr " " reg "1, [%2]\n" \
+ "2:\n" \
+ " .section .fixup, \"ax\"\n" \
+ " .align 2\n" \
+ "3: mov %0, %3\n" \
+ " mov %1, #0\n" \
+ " b 2b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .align 3\n" \
+ " .quad 1b, 3b\n" \
+ " .previous" \
+ : "+r" (err), "=&r" (x) \
+ : "r" (addr), "i" (-EFAULT) \
+ : "cc")
+
+#define __put_user(x,ptr) \
+({ \
+ long __pu_err = 0; \
+ __put_user_err((x),(ptr),__pu_err); \
+ __pu_err; \
+})
+
+#define __put_user_error(x,ptr,err) \
+({ \
+ __put_user_err((x),(ptr),err); \
+ (void) 0; \
+})
+
+#define __put_user_err(x,ptr,err) \
+do { \
+ unsigned long __pu_addr = (unsigned long)(ptr); \
+ __typeof__(*(ptr)) __pu_val = (x); \
+ __chk_user_ptr(ptr); \
+ switch (sizeof(*(ptr))) { \
+ case 1: \
+ __put_user_asm("strb", "%w", __pu_val, __pu_addr, err); \
+ break; \
+ case 2: \
+ __put_user_asm("strh", "%w", __pu_val, __pu_addr, err); \
+ break; \
+ case 4: \
+ __put_user_asm("str", "%w", __pu_val, __pu_addr, err); \
+ break; \
+ case 8: \
+ __put_user_asm("str", "%", __pu_val, __pu_addr, err); \
+ break; \
+ default: \
+ __put_user_bad(); \
+ } \
+} while (0)
+
+#define __put_user_asm(instr, reg, x, __pu_addr, err) \
+ asm volatile( \
+ "1: " instr " " reg "1, [%2]\n" \
+ "2:\n" \
+ " .section .fixup,\"ax\"\n" \
+ " .align 2\n" \
+ "3: mov %0, %3\n" \
+ " b 2b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .align 3\n" \
+ " .quad 1b, 3b\n" \
+ " .previous" \
+ : "+r" (err) \
+ : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
+ : "cc")
+
+extern unsigned long __must_check __copy_from_user(void *to, const void __user *from, unsigned long n);
+extern unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n);
+extern unsigned long __must_check __copy_in_user(void __user *to, const void __user *from, unsigned long n);
+extern unsigned long __must_check __clear_user(void __user *addr, unsigned long n);
+
+extern unsigned long __must_check __strncpy_from_user(char *to, const char __user *from, unsigned long count);
+extern unsigned long __must_check __strnlen_user(const char __user *s, long n);
+
+static inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+ if (access_ok(VERIFY_READ, from, n))
+ n = __copy_from_user(to, from, n);
+ else /* security hole - plug it */
+ memset(to, 0, n);
+ return n;
+}
+
+static inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+ if (access_ok(VERIFY_WRITE, to, n))
+ n = __copy_to_user(to, from, n);
+ return n;
+}
+
+static inline unsigned long __must_check copy_in_user(void __user *to, const void __user *from, unsigned long n)
+{
+ if (access_ok(VERIFY_READ, from, n) && access_ok(VERIFY_WRITE, to, n))
+ n = __copy_in_user(to, from, n);
+ return n;
+}
+
+#define __copy_to_user_inatomic __copy_to_user
+#define __copy_from_user_inatomic __copy_from_user
+
+static inline unsigned long __must_check clear_user(void __user *to, unsigned long n)
+{
+ if (access_ok(VERIFY_WRITE, to, n))
+ n = __clear_user(to, n);
+ return n;
+}
+
+static inline long __must_check strncpy_from_user(char *dst, const char __user *src, long count)
+{
+ long res = -EFAULT;
+ if (access_ok(VERIFY_READ, src, 1))
+ res = __strncpy_from_user(dst, src, count);
+ return res;
+}
+
+#define strlen_user(s) strnlen_user(s, ~0UL >> 1)
+
+static inline long __must_check strnlen_user(const char __user *s, long n)
+{
+ unsigned long res = 0;
+
+ if (__addr_ok(s))
+ res = __strnlen_user(s, n);
+
+ return res;
+}
+
+#endif /* __ASM_UACCESS_H */
diff --git a/arch/aarch64/lib/clear_user.S b/arch/aarch64/lib/clear_user.S
new file mode 100644
index 0000000..1654c19
--- /dev/null
+++ b/arch/aarch64/lib/clear_user.S
@@ -0,0 +1,59 @@
+/*
+ * Based on arch/arm/lib/clear_user.S
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+ .text
+
+/* Prototype: int __clear_user(void *addr, size_t sz)
+ * Purpose : clear some user memory
+ * Params : addr - user memory address to clear
+ * : sz - number of bytes to clear
+ * Returns : number of bytes NOT cleared
+ *
+ * Alignment fixed up by hardware.
+ */
+ENTRY(__clear_user)
+ mov x2, x1 // save the size for fixup return
+ subs x1, x1, #8
+ b.mi 2f
+1:
+USER( str xzr, [x0], #8 )
+ subs x1, x1, #8
+ b.pl 1b
+2: adds x1, x1, #4
+ b.mi 3f
+USER( str wzr, [x0], #4 )
+ sub x1, x1, #4
+3: adds x1, x1, #2
+ b.mi 4f
+USER( strh wzr, [x0], #2 )
+ sub x1, x1, #2
+4: adds x1, x1, #1
+ b.mi 5f
+ strb wzr, [x0]
+5: mov x0, #0
+ ret
+ENDPROC(__clear_user)
+
+ .section .fixup,"ax"
+ .align 2
+9001: mov x0, x2 // return the original size
+ ret
+ .previous
diff --git a/arch/aarch64/lib/copy_from_user.S b/arch/aarch64/lib/copy_from_user.S
new file mode 100644
index 0000000..d0c33b6
--- /dev/null
+++ b/arch/aarch64/lib/copy_from_user.S
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * Copy from user space to a kernel buffer (alignment handled by the hardware)
+ *
+ * Parameters:
+ * x0 - to
+ * x1 - from
+ * x2 - n
+ * Returns:
+ * x0 - bytes not copied
+ */
+ENTRY(__copy_from_user)
+ add x4, x1, x2 // upper user buffer boundary
+ subs x2, x2, #8
+ b.mi 2f
+1:
+USER( ldr x3, [x1], #8 )
+ subs x2, x2, #8
+ str x3, [x0], #8
+ b.pl 1b
+2: adds x2, x2, #4
+ b.mi 3f
+USER( ldr w3, [x1], #4 )
+ sub x2, x2, #4
+ str w3, [x0], #4
+3: adds x2, x2, #2
+ b.mi 4f
+USER( ldrh w3, [x1], #2 )
+ sub x2, x2, #2
+ strh w3, [x0], #2
+4: adds x2, x2, #1
+ b.mi 5f
+USER( ldrb w3, [x1] )
+ strb w3, [x0]
+5: mov x0, #0
+ ret
+ENDPROC(__copy_from_user)
+
+ .section .fixup,"ax"
+ .align 2
+9001: sub x2, x4, x1
+ mov x3, x2
+9002: strb wzr, [x0], #1 // zero remaining buffer space
+ subs x3, x3, #1
+ b.ne 9002b
+ mov x0, x2 // bytes not copied
+ ret
+ .previous
diff --git a/arch/aarch64/lib/copy_in_user.S b/arch/aarch64/lib/copy_in_user.S
new file mode 100644
index 0000000..cc95934
--- /dev/null
+++ b/arch/aarch64/lib/copy_in_user.S
@@ -0,0 +1,64 @@
+/*
+ * arch/aarch64/lib/copy_in_user.S
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * Copy from user space to user space (alignment handled by the hardware)
+ *
+ * Parameters:
+ * x0 - to
+ * x1 - from
+ * x2 - n
+ * Returns:
+ * x0 - bytes not copied
+ */
+ENTRY(__copy_in_user)
+ add x4, x0, x2 // upper user buffer boundary
+ subs x2, x2, #8
+ b.mi 2f
+1:
+USER( ldr x3, [x1], #8 )
+ subs x2, x2, #8
+USER( str x3, [x0], #8 )
+ b.pl 1b
+2: adds x2, x2, #4
+ b.mi 3f
+USER( ldr w3, [x1], #4 )
+ sub x2, x2, #4
+USER( str w3, [x0], #4 )
+3: adds x2, x2, #2
+ b.mi 4f
+USER( ldrh w3, [x1], #2 )
+ sub x2, x2, #2
+USER( strh w3, [x0], #2 )
+4: adds x2, x2, #1
+ b.mi 5f
+USER( ldrb w3, [x1] )
+USER( strb w3, [x0] )
+5: mov x0, #0
+ ret
+ENDPROC(__copy_in_user)
+
+ .section .fixup,"ax"
+ .align 2
+9001: sub x0, x4, x0 // bytes not copied
+ ret
+ .previous
diff --git a/arch/aarch64/lib/copy_to_user.S b/arch/aarch64/lib/copy_to_user.S
new file mode 100644
index 0000000..506c797
--- /dev/null
+++ b/arch/aarch64/lib/copy_to_user.S
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * Copy to user space from a kernel buffer (alignment handled by the hardware)
+ *
+ * Parameters:
+ * x0 - to
+ * x1 - from
+ * x2 - n
+ * Returns:
+ * x0 - bytes not copied
+ */
+ENTRY(__copy_to_user)
+ add x4, x0, x2 // upper user buffer boundary
+ subs x2, x2, #8
+ b.mi 2f
+1:
+ ldr x3, [x1], #8
+ subs x2, x2, #8
+USER( str x3, [x0], #8 )
+ b.pl 1b
+2: adds x2, x2, #4
+ b.mi 3f
+ ldr w3, [x1], #4
+ sub x2, x2, #4
+USER( str w3, [x0], #4 )
+3: adds x2, x2, #2
+ b.mi 4f
+ ldrh w3, [x1], #2
+ sub x2, x2, #2
+USER( strh w3, [x0], #2 )
+4: adds x2, x2, #1
+ b.mi 5f
+ ldrb w3, [x1]
+USER( strb w3, [x0] )
+5: mov x0, #0
+ ret
+ENDPROC(__copy_to_user)
+
+ .section .fixup,"ax"
+ .align 2
+9001: sub x0, x4, x0 // bytes not copied
+ ret
+ .previous
diff --git a/arch/aarch64/lib/getuser.S b/arch/aarch64/lib/getuser.S
new file mode 100644
index 0000000..ba3c15c
--- /dev/null
+++ b/arch/aarch64/lib/getuser.S
@@ -0,0 +1,76 @@
+/*
+ * Based on arch/arm/lib/getuser.S
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ * Idea from x86 version, (C) Copyright 1998 Linus Torvalds
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ *
+ * These functions have a non-standard call interface to make them more
+ * efficient, especially as they return an error value in addition to
+ * the "real" return value.
+ *
+ * __get_user_X
+ *
+ * Inputs: x0 contains the address
+ * Outputs: x0 is the error code
+ * x2, x3 contains the zero-extended value
+ * lr corrupted
+ *
+ * No other registers must be altered. (see <asm/uaccess.h>
+ * for specific ASM register usage).
+ *
+ * Note also that it is intended that __get_user_bad is not global.
+ */
+
+#include <linux/linkage.h>
+#include <asm/errno.h>
+
+ENTRY(__get_user_1)
+1: ldrb w2, [x0]
+ mov x0, #0
+ ret
+ENDPROC(__get_user_1)
+
+ENTRY(__get_user_2)
+2: ldrh w2, [x0]
+ mov x0, #0
+ ret
+ENDPROC(__get_user_2)
+
+ENTRY(__get_user_4)
+3: ldr w2, [x0]
+ mov x0, #0
+ ret
+ENDPROC(__get_user_4)
+
+ENTRY(__get_user_8)
+4: ldr x2, [x0]
+ mov x0, #0
+ ret
+ENDPROC(__get_user_4)
+
+__get_user_bad:
+ mov x2, #0
+ mov x0, #-EFAULT
+ ret
+ENDPROC(__get_user_bad)
+
+.section __ex_table, "a"
+ .quad 1b, __get_user_bad
+ .quad 2b, __get_user_bad
+ .quad 3b, __get_user_bad
+ .quad 4b, __get_user_bad
+.previous
diff --git a/arch/aarch64/lib/putuser.S b/arch/aarch64/lib/putuser.S
new file mode 100644
index 0000000..b2068ba
--- /dev/null
+++ b/arch/aarch64/lib/putuser.S
@@ -0,0 +1,74 @@
+/*
+ * Based on arch/arm/lib/putuser.S
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ * Idea from x86 version, (C) Copyright 1998 Linus Torvalds
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * These functions have a non-standard call interface to make
+ * them more efficient, especially as they return an error
+ * value in addition to the "real" return value.
+ *
+ * __put_user_X
+ *
+ * Inputs: x0 contains the address
+ * x2, x3 contains the value
+ * Outputs: x0 is the error code
+ * lr corrupted
+ *
+ * No other registers must be altered. (see <asm/uaccess.h>
+ * for specific ASM register usage).
+ *
+ * Note that it is intended that __put_user_bad is not global.
+ */
+
+#include <linux/linkage.h>
+#include <asm/errno.h>
+
+ENTRY(__put_user_1)
+1: strb w2, [x0]
+ mov x0, #0
+ ret
+ENDPROC(__put_user_1)
+
+ENTRY(__put_user_2)
+2: strh w2, [x0]
+ mov x0, #0
+ ret
+ENDPROC(__put_user_2)
+
+ENTRY(__put_user_4)
+3: str w2, [x0]
+ mov x0, #0
+ ret
+ENDPROC(__put_user_4)
+
+ENTRY(__put_user_8)
+4: str x2, [x0]
+ mov x0, #0
+ ret
+ENDPROC(__put_user_8)
+
+__put_user_bad:
+ mov x0, #-EFAULT
+ ret
+ENDPROC(__put_user_bad)
+
+.section __ex_table, "a"
+ .quad 1b, __put_user_bad
+ .quad 2b, __put_user_bad
+ .quad 3b, __put_user_bad
+ .quad 4b, __put_user_bad
+.previous
diff --git a/arch/aarch64/lib/strncpy_from_user.S b/arch/aarch64/lib/strncpy_from_user.S
new file mode 100644
index 0000000..78f2e8d
--- /dev/null
+++ b/arch/aarch64/lib/strncpy_from_user.S
@@ -0,0 +1,51 @@
+/*
+ * Based on arch/arm/lib/strncpy_from_user.S
+ *
+ * Copyright (C) 1995-2000 Russell King
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/errno.h>
+
+ .text
+ .align 5
+
+/*
+ * Copy a string from user space to kernel space.
+ * x0 = dst, x1 = src, x2 = byte length
+ * returns the number of characters copied (strlen of copied string),
+ * -EFAULT on exception, or "len" if we fill the whole buffer
+ */
+ENTRY(__strncpy_from_user)
+ mov x4, x1
+1: subs x2, x2, #1
+ bmi 2f
+USER( ldrb w3, [x1], #1 )
+ strb w3, [x0], #1
+ cbnz w3, 1b
+ sub x1, x1, #1 // take NUL character out of count
+2: sub x0, x1, x4
+ ret
+ENDPROC(__strncpy_from_user)
+
+ .section .fixup,"ax"
+ .align 0
+9001: strb wzr, [x0] // null terminate
+ mov x0, #-EFAULT
+ ret
+ .previous
diff --git a/arch/aarch64/lib/strnlen_user.S b/arch/aarch64/lib/strnlen_user.S
new file mode 100644
index 0000000..84bccab
--- /dev/null
+++ b/arch/aarch64/lib/strnlen_user.S
@@ -0,0 +1,48 @@
+/*
+ * Based on arch/arm/lib/strnlen_user.S
+ *
+ * Copyright (C) 1995-2000 Russell King
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/errno.h>
+
+ .text
+ .align 5
+
+/* Prototype: unsigned long __strnlen_user(const char *str, long n)
+ * Purpose : get length of a string in user memory
+ * Params : str - address of string in user memory
+ * Returns : length of string *including terminator*
+ * or zero on exception, or n if too long
+ */
+ENTRY(__strnlen_user)
+ mov x2, x0
+1: subs x1, x1, #1
+ b.mi 2f
+USER( ldrb w3, [x0], #1 )
+ cbnz w3, 1b
+2: sub x0, x0, x2
+ ret
+ENDPROC(__strnlen_user)
+
+ .section .fixup,"ax"
+ .align 0
+9001: mov x0, #0
+ ret
+ .previous
next prev parent reply other threads:[~2012-07-06 21:10 UTC|newest]
Thread overview: 182+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-06 21:05 [PATCH 00/36] AArch64 Linux kernel port Catalin Marinas
2012-07-06 21:05 ` [PATCH 01/36] atomic64_test: Simplify the #ifdef for atomic64_dec_if_positive() test Catalin Marinas
2012-07-18 4:33 ` Benjamin Herrenschmidt
2012-07-18 9:06 ` Catalin Marinas
2012-07-06 21:05 ` [PATCH 02/36] ipc: Add COMPAT_SHMLBA support Catalin Marinas
2012-07-18 5:53 ` Jon Masters
2012-07-18 9:03 ` Will Deacon
2012-07-06 21:05 ` [PATCH 03/36] ipc: allow compat IPC version field parsing if !ARCH_WANT_OLD_COMPAT_IPC Catalin Marinas
2012-07-06 21:05 ` [PATCH 04/36] ipc: compat: use signed size_t types for msgsnd and msgrcv Catalin Marinas
2012-07-06 21:05 ` [PATCH 05/36] fs: Build sys_stat64() and friends if __ARCH_WANT_COMPAT_STAT64 Catalin Marinas
2012-07-06 21:05 ` [PATCH 06/36] fdt: Add generic dt_memblock_reserve() function Catalin Marinas
2012-07-07 21:18 ` Rob Herring
2012-07-08 9:43 ` Catalin Marinas
2012-07-06 21:05 ` [PATCH 07/36] AArch64: Assembly macros and definitions Catalin Marinas
2012-07-07 5:57 ` Greg KH
2012-07-08 9:23 ` Catalin Marinas
2012-07-20 14:22 ` [07/36] " Christopher Covington
2012-07-24 16:40 ` Catalin Marinas
2012-07-06 21:05 ` [PATCH 08/36] AArch64: Kernel booting and initialisation Catalin Marinas
2012-07-06 21:32 ` Stephen Warren
2012-07-08 9:18 ` Catalin Marinas
2012-07-23 17:48 ` Stephen Warren
2012-07-23 17:58 ` Catalin Marinas
2012-07-18 6:57 ` Jon Masters
2012-07-18 9:07 ` Will Deacon
2012-07-20 7:11 ` Jon Masters
2012-07-19 17:31 ` Christopher Covington
2012-07-20 7:10 ` Jon Masters
2012-07-20 8:28 ` Arnd Bergmann
2012-07-20 10:52 ` Catalin Marinas
2012-07-20 12:32 ` Geert Uytterhoeven
2012-07-20 13:16 ` Catalin Marinas
2012-07-20 13:47 ` Christopher Covington
2012-07-20 13:52 ` Catalin Marinas
2012-07-20 13:48 ` Catalin Marinas
2012-07-20 14:53 ` Christopher Covington
2012-07-23 20:52 ` [08/36] " Christopher Covington
2012-07-24 16:24 ` Catalin Marinas
2012-07-24 18:53 ` Arnd Bergmann
2012-07-24 23:20 ` Frank Rowand
2012-07-25 8:34 ` Catalin Marinas
2012-07-24 19:42 ` Christopher Covington
2012-07-25 8:47 ` Catalin Marinas
2012-07-25 13:39 ` Christopher Covington
2012-07-06 21:05 ` [PATCH 09/36] AArch64: Exception handling Catalin Marinas
2012-08-09 17:05 ` [09/36] " Christopher Covington
2012-08-09 17:23 ` Catalin Marinas
2012-08-09 19:19 ` Christopher Covington
2012-07-06 21:05 ` [PATCH 10/36] AArch64: MMU definitions Catalin Marinas
2012-10-02 0:43 ` Jon Masters
2012-10-02 15:39 ` Catalin Marinas
2012-07-06 21:05 ` [PATCH 11/36] AArch64: MMU initialisation Catalin Marinas
2012-07-06 21:05 ` [PATCH 12/36] AArch64: MMU fault handling and page table management Catalin Marinas
2012-07-06 21:05 ` [PATCH 13/36] AArch64: Process management Catalin Marinas
2012-07-06 21:05 ` [PATCH 14/36] AArch64: CPU support Catalin Marinas
2012-07-06 21:05 ` [PATCH 15/36] AArch64: Cache maintenance routines Catalin Marinas
2012-07-06 21:05 ` [PATCH 16/36] AArch64: TLB maintenance functionality Catalin Marinas
2012-07-06 21:05 ` [PATCH 17/36] AArch64: IRQ handling Catalin Marinas
2012-07-06 21:05 ` [PATCH 18/36] AArch64: Atomic operations Catalin Marinas
2012-07-06 21:06 ` [PATCH 19/36] AArch64: Device specific operations Catalin Marinas
2012-07-06 21:06 ` [PATCH 20/36] AArch64: DMA mapping API Catalin Marinas
2012-07-06 21:06 ` [PATCH 21/36] AArch64: SMP support Catalin Marinas
2012-07-06 21:06 ` [PATCH 22/36] AArch64: ELF definitions Catalin Marinas
2012-07-06 21:06 ` [PATCH 23/36] AArch64: System calls handling Catalin Marinas
2012-07-06 21:06 ` [PATCH 24/36] AArch64: VDSO support Catalin Marinas
2012-07-06 21:06 ` [PATCH 25/36] AArch64: Signal handling support Catalin Marinas
2012-07-06 21:06 ` Catalin Marinas [this message]
2012-07-06 21:06 ` [PATCH 27/36] AArch64: 32-bit (compat) applications support Catalin Marinas
2012-07-06 21:06 ` [PATCH 28/36] AArch64: Floating point and SIMD Catalin Marinas
2012-07-06 21:06 ` [PATCH 29/36] AArch64: Debugging support Catalin Marinas
2012-07-06 21:06 ` [PATCH 30/36] AArch64: Performance counters support Catalin Marinas
2012-07-06 21:06 ` [PATCH 31/36] AArch64: Miscellaneous library functions Catalin Marinas
2012-07-06 21:06 ` [PATCH 32/36] AArch64: Loadable modules Catalin Marinas
2012-07-06 21:06 ` [PATCH 33/36] AArch64: Generic timers support Catalin Marinas
2012-07-12 0:18 ` Linus Walleij
2012-07-12 10:09 ` Marc Zyngier
2012-07-12 10:56 ` Linus Walleij
2012-07-12 16:57 ` John Stultz
2012-07-12 17:31 ` Marc Zyngier
2012-07-12 17:39 ` John Stultz
2012-07-13 12:40 ` Arnd Bergmann
2012-07-13 16:02 ` Catalin Marinas
2012-07-13 16:32 ` Arnd Bergmann
2012-07-13 18:30 ` John Stultz
2012-07-06 21:06 ` [PATCH 34/36] AArch64: Miscellaneous header files Catalin Marinas
2012-07-06 21:06 ` [PATCH 35/36] AArch64: Build infrastructure Catalin Marinas
2012-07-06 21:06 ` [PATCH 36/36] AArch64: MAINTAINERS update Catalin Marinas
2012-08-10 16:24 ` [36/36] " Christopher Covington
2012-07-06 22:58 ` [PATCH 00/36] AArch64 Linux kernel port Alan Cox
2012-07-07 21:30 ` Arnd Bergmann
2012-07-07 23:14 ` Catalin Marinas
2012-07-07 23:29 ` Alan Cox
2012-07-09 11:35 ` Catalin Marinas
2012-07-09 13:51 ` Alan Cox
2012-07-09 15:32 ` Arnd Bergmann
2012-07-09 15:49 ` Alan Cox
2012-07-09 16:02 ` Catalin Marinas
2012-07-09 16:33 ` Arnd Bergmann
2012-07-07 3:29 ` Matthew Garrett
2012-07-09 12:32 ` Mark Brown
2012-07-09 13:06 ` Matthew Garrett
2012-07-09 13:56 ` Mark Brown
2012-07-09 14:02 ` Matthew Garrett
2012-07-09 15:46 ` Mark Brown
2012-07-07 3:53 ` Olof Johansson
2012-07-07 19:27 ` Arnd Bergmann
2012-07-07 23:45 ` Jan Engelhardt
2012-07-08 5:05 ` Henrique de Moraes Holschuh
2012-07-08 20:28 ` Jan Engelhardt
2012-07-08 7:54 ` Jon Masters
2012-07-08 11:17 ` Dr. David Alan Gilbert
2012-07-08 18:13 ` Jon Masters
2012-07-08 18:31 ` Jon Masters
2012-07-08 22:24 ` Dennis Gilmore
2012-07-09 2:01 ` Jon Masters
2012-07-09 8:57 ` Catalin Marinas
2012-07-09 13:33 ` Geert Uytterhoeven
2012-07-08 20:31 ` Jan Engelhardt
2012-07-08 23:32 ` Jon Masters
2012-07-10 7:10 ` Ingo Molnar
2012-07-10 10:10 ` Catalin Marinas
2012-07-10 15:33 ` Alan Cox
2012-07-10 16:52 ` Arnd Bergmann
2012-07-10 20:35 ` Ingo Molnar
2012-07-10 21:19 ` Arnd Bergmann
2012-07-10 21:48 ` Catalin Marinas
2012-07-11 8:20 ` Ingo Molnar
2012-07-11 11:30 ` Alan Cox
2012-07-10 21:44 ` Catalin Marinas
2012-07-11 8:55 ` Catalin Marinas
2012-07-11 5:26 ` Rusty Russell
2012-07-11 10:53 ` Catalin Marinas
2012-07-12 2:08 ` Rusty Russell
2012-07-10 16:57 ` Catalin Marinas
2012-07-10 16:52 ` Dennis Gilmore
2012-07-10 17:14 ` Joe Perches
2012-07-10 18:01 ` Jan Ceuleers
2012-07-10 18:05 ` richard -rw- weinberger
2012-07-10 20:16 ` Alexander Holler
2012-07-14 22:16 ` Jon Masters
2012-07-10 22:08 ` Chris Adams
2012-07-14 9:30 ` Pavel Machek
2012-07-15 12:16 ` Catalin Marinas
2012-07-15 19:43 ` Arnd Bergmann
2012-07-15 21:33 ` Catalin Marinas
2012-07-16 12:16 ` Pavel Machek
2012-07-17 7:05 ` Jon Masters
2012-07-17 8:02 ` Arnd Bergmann
2012-07-17 9:50 ` Alan Cox
2012-07-18 2:36 ` Jon Masters
2012-07-17 10:45 ` Catalin Marinas
2012-07-16 9:26 ` Geert Uytterhoeven
2012-07-17 6:53 ` Christoph Hellwig
2012-07-17 8:07 ` Arnd Bergmann
2012-07-16 8:24 ` Avi Kivity
2012-07-17 7:09 ` Jon Masters
2012-07-17 8:37 ` Catalin Marinas
2012-07-15 23:21 ` Måns Rullgård
2012-07-15 23:53 ` Linus Torvalds
2012-07-17 22:18 ` Catalin Marinas
2012-07-17 22:35 ` Joe Perches
2012-07-18 2:33 ` Jon Masters
2012-07-18 15:27 ` Dennis Gilmore
2012-07-18 17:14 ` Catalin Marinas
2012-07-18 17:25 ` Måns Rullgård
2012-07-18 19:35 ` Jon Masters
2012-07-18 19:55 ` Linus Torvalds
2012-07-19 14:16 ` Guillem Jover
2012-07-07 23:42 ` Jan Engelhardt
2012-07-08 10:18 ` Catalin Marinas
2012-07-09 12:31 ` Jan Engelhardt
2012-07-07 9:30 ` Mikael Pettersson
2012-07-07 19:21 ` Kirill A. Shutemov
2012-07-10 10:12 ` Catalin Marinas
2012-07-14 9:35 ` Pavel Machek
2012-07-15 11:36 ` Catalin Marinas
2012-07-16 16:19 ` Pavel Machek
2012-07-16 19:45 ` Arnd Bergmann
2012-07-16 19:47 ` Måns Rullgård
2012-07-18 5:35 ` Jon Masters
2012-07-18 9:13 ` Catalin Marinas
2012-07-26 11:59 ` Catalin Marinas
[not found] <jknWN-4WG-3@gated-at.bofh.it>
[not found] ` <jkulA-O3-3@gated-at.bofh.it>
[not found] ` <jkIRz-2Hu-11@gated-at.bofh.it>
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