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-rw-r--r--include/asm-m68k/uaccess.h893
1 files changed, 893 insertions, 0 deletions
diff --git a/include/asm-m68k/uaccess.h b/include/asm-m68k/uaccess.h
new file mode 100644
index 000000000000..605e6cb811f8
--- /dev/null
+++ b/include/asm-m68k/uaccess.h
@@ -0,0 +1,893 @@
+#ifndef __M68K_UACCESS_H
+#define __M68K_UACCESS_H
+
+/*
+ * User space memory access functions
+ */
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <asm/segment.h>
+
+#define VERIFY_READ 0
+#define VERIFY_WRITE 1
+
+/* We let the MMU do all checking */
+#define access_ok(type,addr,size) 1
+
+/* this function will go away soon - use access_ok() instead */
+static inline int __deprecated verify_area(int type, const void *addr, unsigned long size)
+{
+ return access_ok(type,addr,size) ? 0 : -EFAULT;
+}
+
+/*
+ * 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;
+};
+
+
+/*
+ * These are the main single-value transfer routines. They automatically
+ * use the right size if we just have the right pointer type.
+ */
+
+#define put_user(x, ptr) \
+({ \
+ int __pu_err; \
+ typeof(*(ptr)) __pu_val = (x); \
+ switch (sizeof (*(ptr))) { \
+ case 1: \
+ __put_user_asm(__pu_err, __pu_val, ptr, b); \
+ break; \
+ case 2: \
+ __put_user_asm(__pu_err, __pu_val, ptr, w); \
+ break; \
+ case 4: \
+ __put_user_asm(__pu_err, __pu_val, ptr, l); \
+ break; \
+ case 8: \
+ __pu_err = __constant_copy_to_user(ptr, &__pu_val, 8); \
+ break; \
+ default: \
+ __pu_err = __put_user_bad(); \
+ break; \
+ } \
+ __pu_err; \
+})
+#define __put_user(x, ptr) put_user(x, ptr)
+
+extern int __put_user_bad(void);
+
+/*
+ * Tell gcc we read from memory instead of writing: this is because
+ * we do not write to any memory gcc knows about, so there are no
+ * aliasing issues.
+ */
+#define __put_user_asm(err,x,ptr,bwl) \
+__asm__ __volatile__ \
+ ("21:moves" #bwl " %2,%1\n" \
+ "1:\n" \
+ ".section .fixup,\"ax\"\n" \
+ " .even\n" \
+ "2: movel %3,%0\n" \
+ " jra 1b\n" \
+ ".previous\n" \
+ ".section __ex_table,\"a\"\n" \
+ " .align 4\n" \
+ " .long 21b,2b\n" \
+ " .long 1b,2b\n" \
+ ".previous" \
+ : "=d"(err) \
+ : "m"(*(ptr)), "r"(x), "i"(-EFAULT), "0"(0))
+
+#define get_user(x, ptr) \
+({ \
+ int __gu_err; \
+ typeof(*(ptr)) __gu_val; \
+ switch (sizeof(*(ptr))) { \
+ case 1: \
+ __get_user_asm(__gu_err, __gu_val, ptr, b, "=d"); \
+ break; \
+ case 2: \
+ __get_user_asm(__gu_err, __gu_val, ptr, w, "=r"); \
+ break; \
+ case 4: \
+ __get_user_asm(__gu_err, __gu_val, ptr, l, "=r"); \
+ break; \
+ case 8: \
+ __gu_err = __constant_copy_from_user(&__gu_val, ptr, 8); \
+ break; \
+ default: \
+ __gu_val = 0; \
+ __gu_err = __get_user_bad(); \
+ break; \
+ } \
+ (x) = __gu_val; \
+ __gu_err; \
+})
+#define __get_user(x, ptr) get_user(x, ptr)
+
+extern int __get_user_bad(void);
+
+#define __get_user_asm(err,x,ptr,bwl,reg) \
+__asm__ __volatile__ \
+ ("1: moves" #bwl " %2,%1\n" \
+ "2:\n" \
+ ".section .fixup,\"ax\"\n" \
+ " .even\n" \
+ "3: movel %3,%0\n" \
+ " sub" #bwl " %1,%1\n" \
+ " jra 2b\n" \
+ ".previous\n" \
+ ".section __ex_table,\"a\"\n" \
+ " .align 4\n" \
+ " .long 1b,3b\n" \
+ ".previous" \
+ : "=d"(err), reg(x) \
+ : "m"(*(ptr)), "i" (-EFAULT), "0"(0))
+
+static inline unsigned long
+__generic_copy_from_user(void *to, const void *from, unsigned long n)
+{
+ unsigned long tmp;
+ __asm__ __volatile__
+ (" tstl %2\n"
+ " jeq 2f\n"
+ "1: movesl (%1)+,%3\n"
+ " movel %3,(%0)+\n"
+ " subql #1,%2\n"
+ " jne 1b\n"
+ "2: movel %4,%2\n"
+ " bclr #1,%2\n"
+ " jeq 4f\n"
+ "3: movesw (%1)+,%3\n"
+ " movew %3,(%0)+\n"
+ "4: bclr #0,%2\n"
+ " jeq 6f\n"
+ "5: movesb (%1)+,%3\n"
+ " moveb %3,(%0)+\n"
+ "6:\n"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "7: movel %2,%%d0\n"
+ "71:clrl (%0)+\n"
+ " subql #1,%%d0\n"
+ " jne 71b\n"
+ " lsll #2,%2\n"
+ " addl %4,%2\n"
+ " btst #1,%4\n"
+ " jne 81f\n"
+ " btst #0,%4\n"
+ " jne 91f\n"
+ " jra 6b\n"
+ "8: addql #2,%2\n"
+ "81:clrw (%0)+\n"
+ " btst #0,%4\n"
+ " jne 91f\n"
+ " jra 6b\n"
+ "9: addql #1,%2\n"
+ "91:clrb (%0)+\n"
+ " jra 6b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 1b,7b\n"
+ " .long 3b,8b\n"
+ " .long 5b,9b\n"
+ ".previous"
+ : "=a"(to), "=a"(from), "=d"(n), "=&d"(tmp)
+ : "d"(n & 3), "0"(to), "1"(from), "2"(n/4)
+ : "d0", "memory");
+ return n;
+}
+
+static inline unsigned long
+__generic_copy_to_user(void *to, const void *from, unsigned long n)
+{
+ unsigned long tmp;
+ __asm__ __volatile__
+ (" tstl %2\n"
+ " jeq 3f\n"
+ "1: movel (%1)+,%3\n"
+ "22:movesl %3,(%0)+\n"
+ "2: subql #1,%2\n"
+ " jne 1b\n"
+ "3: movel %4,%2\n"
+ " bclr #1,%2\n"
+ " jeq 4f\n"
+ " movew (%1)+,%3\n"
+ "24:movesw %3,(%0)+\n"
+ "4: bclr #0,%2\n"
+ " jeq 5f\n"
+ " moveb (%1)+,%3\n"
+ "25:movesb %3,(%0)+\n"
+ "5:\n"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "60:addql #1,%2\n"
+ "6: lsll #2,%2\n"
+ " addl %4,%2\n"
+ " jra 5b\n"
+ "7: addql #2,%2\n"
+ " jra 5b\n"
+ "8: addql #1,%2\n"
+ " jra 5b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 1b,60b\n"
+ " .long 22b,6b\n"
+ " .long 2b,6b\n"
+ " .long 24b,7b\n"
+ " .long 3b,60b\n"
+ " .long 4b,7b\n"
+ " .long 25b,8b\n"
+ " .long 5b,8b\n"
+ ".previous"
+ : "=a"(to), "=a"(from), "=d"(n), "=&d"(tmp)
+ : "r"(n & 3), "0"(to), "1"(from), "2"(n / 4)
+ : "memory");
+ return n;
+}
+
+#define __copy_from_user_big(to, from, n, fixup, copy) \
+ __asm__ __volatile__ \
+ ("10: movesl (%1)+,%%d0\n" \
+ " movel %%d0,(%0)+\n" \
+ " subql #1,%2\n" \
+ " jne 10b\n" \
+ ".section .fixup,\"ax\"\n" \
+ " .even\n" \
+ "11: movel %2,%%d0\n" \
+ "13: clrl (%0)+\n" \
+ " subql #1,%%d0\n" \
+ " jne 13b\n" \
+ " lsll #2,%2\n" \
+ fixup "\n" \
+ " jra 12f\n" \
+ ".previous\n" \
+ ".section __ex_table,\"a\"\n" \
+ " .align 4\n" \
+ " .long 10b,11b\n" \
+ ".previous\n" \
+ copy "\n" \
+ "12:" \
+ : "=a"(to), "=a"(from), "=d"(n) \
+ : "0"(to), "1"(from), "2"(n/4) \
+ : "d0", "memory")
+
+static inline unsigned long
+__constant_copy_from_user(void *to, const void *from, unsigned long n)
+{
+ switch (n) {
+ case 0:
+ break;
+ case 1:
+ __asm__ __volatile__
+ ("1: movesb (%1)+,%%d0\n"
+ " moveb %%d0,(%0)+\n"
+ "2:\n"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "3: addql #1,%2\n"
+ " clrb (%0)+\n"
+ " jra 2b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 1b,3b\n"
+ ".previous"
+ : "=a"(to), "=a"(from), "=d"(n)
+ : "0"(to), "1"(from), "2"(0)
+ : "d0", "memory");
+ break;
+ case 2:
+ __asm__ __volatile__
+ ("1: movesw (%1)+,%%d0\n"
+ " movew %%d0,(%0)+\n"
+ "2:\n"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "3: addql #2,%2\n"
+ " clrw (%0)+\n"
+ " jra 2b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 1b,3b\n"
+ ".previous"
+ : "=a"(to), "=a"(from), "=d"(n)
+ : "0"(to), "1"(from), "2"(0)
+ : "d0", "memory");
+ break;
+ case 3:
+ __asm__ __volatile__
+ ("1: movesw (%1)+,%%d0\n"
+ " movew %%d0,(%0)+\n"
+ "2: movesb (%1)+,%%d0\n"
+ " moveb %%d0,(%0)+\n"
+ "3:"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "4: addql #2,%2\n"
+ " clrw (%0)+\n"
+ "5: addql #1,%2\n"
+ " clrb (%0)+\n"
+ " jra 3b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 1b,4b\n"
+ " .long 2b,5b\n"
+ ".previous"
+ : "=a"(to), "=a"(from), "=d"(n)
+ : "0"(to), "1"(from), "2"(0)
+ : "d0", "memory");
+ break;
+ case 4:
+ __asm__ __volatile__
+ ("1: movesl (%1)+,%%d0\n"
+ " movel %%d0,(%0)+\n"
+ "2:"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "3: addql #4,%2\n"
+ " clrl (%0)+\n"
+ " jra 2b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 1b,3b\n"
+ ".previous"
+ : "=a"(to), "=a"(from), "=d"(n)
+ : "0"(to), "1"(from), "2"(0)
+ : "d0", "memory");
+ break;
+ case 8:
+ __asm__ __volatile__
+ ("1: movesl (%1)+,%%d0\n"
+ " movel %%d0,(%0)+\n"
+ "2: movesl (%1)+,%%d0\n"
+ " movel %%d0,(%0)+\n"
+ "3:"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "4: addql #4,%2\n"
+ " clrl (%0)+\n"
+ "5: addql #4,%2\n"
+ " clrl (%0)+\n"
+ " jra 3b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 1b,4b\n"
+ " .long 2b,5b\n"
+ ".previous"
+ : "=a"(to), "=a"(from), "=d"(n)
+ : "0"(to), "1"(from), "2"(0)
+ : "d0", "memory");
+ break;
+ case 12:
+ __asm__ __volatile__
+ ("1: movesl (%1)+,%%d0\n"
+ " movel %%d0,(%0)+\n"
+ "2: movesl (%1)+,%%d0\n"
+ " movel %%d0,(%0)+\n"
+ "3: movesl (%1)+,%%d0\n"
+ " movel %%d0,(%0)+\n"
+ "4:"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "5: addql #4,%2\n"
+ " clrl (%0)+\n"
+ "6: addql #4,%2\n"
+ " clrl (%0)+\n"
+ "7: addql #4,%2\n"
+ " clrl (%0)+\n"
+ " jra 4b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 1b,5b\n"
+ " .long 2b,6b\n"
+ " .long 3b,7b\n"
+ ".previous"
+ : "=a"(to), "=a"(from), "=d"(n)
+ : "0"(to), "1"(from), "2"(0)
+ : "d0", "memory");
+ break;
+ case 16:
+ __asm__ __volatile__
+ ("1: movesl (%1)+,%%d0\n"
+ " movel %%d0,(%0)+\n"
+ "2: movesl (%1)+,%%d0\n"
+ " movel %%d0,(%0)+\n"
+ "3: movesl (%1)+,%%d0\n"
+ " movel %%d0,(%0)+\n"
+ "4: movesl (%1)+,%%d0\n"
+ " movel %%d0,(%0)+\n"
+ "5:"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "6: addql #4,%2\n"
+ " clrl (%0)+\n"
+ "7: addql #4,%2\n"
+ " clrl (%0)+\n"
+ "8: addql #4,%2\n"
+ " clrl (%0)+\n"
+ "9: addql #4,%2\n"
+ " clrl (%0)+\n"
+ " jra 5b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 1b,6b\n"
+ " .long 2b,7b\n"
+ " .long 3b,8b\n"
+ " .long 4b,9b\n"
+ ".previous"
+ : "=a"(to), "=a"(from), "=d"(n)
+ : "0"(to), "1"(from), "2"(0)
+ : "d0", "memory");
+ break;
+ default:
+ switch (n & 3) {
+ case 0:
+ __copy_from_user_big(to, from, n, "", "");
+ break;
+ case 1:
+ __copy_from_user_big(to, from, n,
+ /* fixup */
+ "1: addql #1,%2\n"
+ " clrb (%0)+",
+ /* copy */
+ "2: movesb (%1)+,%%d0\n"
+ " moveb %%d0,(%0)+\n"
+ ".section __ex_table,\"a\"\n"
+ " .long 2b,1b\n"
+ ".previous");
+ break;
+ case 2:
+ __copy_from_user_big(to, from, n,
+ /* fixup */
+ "1: addql #2,%2\n"
+ " clrw (%0)+",
+ /* copy */
+ "2: movesw (%1)+,%%d0\n"
+ " movew %%d0,(%0)+\n"
+ ".section __ex_table,\"a\"\n"
+ " .long 2b,1b\n"
+ ".previous");
+ break;
+ case 3:
+ __copy_from_user_big(to, from, n,
+ /* fixup */
+ "1: addql #2,%2\n"
+ " clrw (%0)+\n"
+ "2: addql #1,%2\n"
+ " clrb (%0)+",
+ /* copy */
+ "3: movesw (%1)+,%%d0\n"
+ " movew %%d0,(%0)+\n"
+ "4: movesb (%1)+,%%d0\n"
+ " moveb %%d0,(%0)+\n"
+ ".section __ex_table,\"a\"\n"
+ " .long 3b,1b\n"
+ " .long 4b,2b\n"
+ ".previous");
+ break;
+ }
+ break;
+ }
+ return n;
+}
+
+#define __copy_to_user_big(to, from, n, fixup, copy) \
+ __asm__ __volatile__ \
+ ("10: movel (%1)+,%%d0\n" \
+ "31: movesl %%d0,(%0)+\n" \
+ "11: subql #1,%2\n" \
+ " jne 10b\n" \
+ "41:\n" \
+ ".section .fixup,\"ax\"\n" \
+ " .even\n" \
+ "22: addql #1,%2\n" \
+ "12: lsll #2,%2\n" \
+ fixup "\n" \
+ " jra 13f\n" \
+ ".previous\n" \
+ ".section __ex_table,\"a\"\n" \
+ " .align 4\n" \
+ " .long 10b,22b\n" \
+ " .long 31b,12b\n" \
+ " .long 11b,12b\n" \
+ " .long 41b,22b\n" \
+ ".previous\n" \
+ copy "\n" \
+ "13:" \
+ : "=a"(to), "=a"(from), "=d"(n) \
+ : "0"(to), "1"(from), "2"(n/4) \
+ : "d0", "memory")
+
+#define __copy_to_user_inatomic __copy_to_user
+#define __copy_from_user_inatomic __copy_from_user
+
+static inline unsigned long
+__constant_copy_to_user(void *to, const void *from, unsigned long n)
+{
+ switch (n) {
+ case 0:
+ break;
+ case 1:
+ __asm__ __volatile__
+ (" moveb (%1)+,%%d0\n"
+ "21:movesb %%d0,(%0)+\n"
+ "1:\n"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "2: addql #1,%2\n"
+ " jra 1b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n "
+ " .long 21b,2b\n"
+ " .long 1b,2b\n"
+ ".previous"
+ : "=a"(to), "=a"(from), "=d"(n)
+ : "0"(to), "1"(from), "2"(0)
+ : "d0", "memory");
+ break;
+ case 2:
+ __asm__ __volatile__
+ (" movew (%1)+,%%d0\n"
+ "21:movesw %%d0,(%0)+\n"
+ "1:\n"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "2: addql #2,%2\n"
+ " jra 1b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 21b,2b\n"
+ " .long 1b,2b\n"
+ ".previous"
+ : "=a"(to), "=a"(from), "=d"(n)
+ : "0"(to), "1"(from), "2"(0)
+ : "d0", "memory");
+ break;
+ case 3:
+ __asm__ __volatile__
+ (" movew (%1)+,%%d0\n"
+ "21:movesw %%d0,(%0)+\n"
+ "1: moveb (%1)+,%%d0\n"
+ "22:movesb %%d0,(%0)+\n"
+ "2:\n"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "3: addql #2,%2\n"
+ "4: addql #1,%2\n"
+ " jra 2b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 21b,3b\n"
+ " .long 1b,3b\n"
+ " .long 22b,4b\n"
+ " .long 2b,4b\n"
+ ".previous"
+ : "=a"(to), "=a"(from), "=d"(n)
+ : "0"(to), "1"(from), "2"(0)
+ : "d0", "memory");
+ break;
+ case 4:
+ __asm__ __volatile__
+ (" movel (%1)+,%%d0\n"
+ "21:movesl %%d0,(%0)+\n"
+ "1:\n"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "2: addql #4,%2\n"
+ " jra 1b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 21b,2b\n"
+ " .long 1b,2b\n"
+ ".previous"
+ : "=a"(to), "=a"(from), "=d"(n)
+ : "0"(to), "1"(from), "2"(0)
+ : "d0", "memory");
+ break;
+ case 8:
+ __asm__ __volatile__
+ (" movel (%1)+,%%d0\n"
+ "21:movesl %%d0,(%0)+\n"
+ "1: movel (%1)+,%%d0\n"
+ "22:movesl %%d0,(%0)+\n"
+ "2:\n"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "3: addql #4,%2\n"
+ "4: addql #4,%2\n"
+ " jra 2b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 21b,3b\n"
+ " .long 1b,3b\n"
+ " .long 22b,4b\n"
+ " .long 2b,4b\n"
+ ".previous"
+ : "=a"(to), "=a"(from), "=d"(n)
+ : "0"(to), "1"(from), "2"(0)
+ : "d0", "memory");
+ break;
+ case 12:
+ __asm__ __volatile__
+ (" movel (%1)+,%%d0\n"
+ "21:movesl %%d0,(%0)+\n"
+ "1: movel (%1)+,%%d0\n"
+ "22:movesl %%d0,(%0)+\n"
+ "2: movel (%1)+,%%d0\n"
+ "23:movesl %%d0,(%0)+\n"
+ "3:\n"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "4: addql #4,%2\n"
+ "5: addql #4,%2\n"
+ "6: addql #4,%2\n"
+ " jra 3b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 21b,4b\n"
+ " .long 1b,4b\n"
+ " .long 22b,5b\n"
+ " .long 2b,5b\n"
+ " .long 23b,6b\n"
+ " .long 3b,6b\n"
+ ".previous"
+ : "=a"(to), "=a"(from), "=d"(n)
+ : "0"(to), "1"(from), "2"(0)
+ : "d0", "memory");
+ break;
+ case 16:
+ __asm__ __volatile__
+ (" movel (%1)+,%%d0\n"
+ "21:movesl %%d0,(%0)+\n"
+ "1: movel (%1)+,%%d0\n"
+ "22:movesl %%d0,(%0)+\n"
+ "2: movel (%1)+,%%d0\n"
+ "23:movesl %%d0,(%0)+\n"
+ "3: movel (%1)+,%%d0\n"
+ "24:movesl %%d0,(%0)+\n"
+ "4:"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "5: addql #4,%2\n"
+ "6: addql #4,%2\n"
+ "7: addql #4,%2\n"
+ "8: addql #4,%2\n"
+ " jra 4b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 21b,5b\n"
+ " .long 1b,5b\n"
+ " .long 22b,6b\n"
+ " .long 2b,6b\n"
+ " .long 23b,7b\n"
+ " .long 3b,7b\n"
+ " .long 24b,8b\n"
+ " .long 4b,8b\n"
+ ".previous"
+ : "=a"(to), "=a"(from), "=d"(n)
+ : "0"(to), "1"(from), "2"(0)
+ : "d0", "memory");
+ break;
+ default:
+ switch (n & 3) {
+ case 0:
+ __copy_to_user_big(to, from, n, "", "");
+ break;
+ case 1:
+ __copy_to_user_big(to, from, n,
+ /* fixup */
+ "1: addql #1,%2",
+ /* copy */
+ " moveb (%1)+,%%d0\n"
+ "22:movesb %%d0,(%0)+\n"
+ "2:"
+ ".section __ex_table,\"a\"\n"
+ " .long 22b,1b\n"
+ " .long 2b,1b\n"
+ ".previous");
+ break;
+ case 2:
+ __copy_to_user_big(to, from, n,
+ /* fixup */
+ "1: addql #2,%2",
+ /* copy */
+ " movew (%1)+,%%d0\n"
+ "22:movesw %%d0,(%0)+\n"
+ "2:"
+ ".section __ex_table,\"a\"\n"
+ " .long 22b,1b\n"
+ " .long 2b,1b\n"
+ ".previous");
+ break;
+ case 3:
+ __copy_to_user_big(to, from, n,
+ /* fixup */
+ "1: addql #2,%2\n"
+ "2: addql #1,%2",
+ /* copy */
+ " movew (%1)+,%%d0\n"
+ "23:movesw %%d0,(%0)+\n"
+ "3: moveb (%1)+,%%d0\n"
+ "24:movesb %%d0,(%0)+\n"
+ "4:"
+ ".section __ex_table,\"a\"\n"
+ " .long 23b,1b\n"
+ " .long 3b,1b\n"
+ " .long 24b,2b\n"
+ " .long 4b,2b\n"
+ ".previous");
+ break;
+ }
+ break;
+ }
+ return n;
+}
+
+#define copy_from_user(to, from, n) \
+(__builtin_constant_p(n) ? \
+ __constant_copy_from_user(to, from, n) : \
+ __generic_copy_from_user(to, from, n))
+
+#define copy_to_user(to, from, n) \
+(__builtin_constant_p(n) ? \
+ __constant_copy_to_user(to, from, n) : \
+ __generic_copy_to_user(to, from, n))
+
+#define __copy_from_user(to, from, n) copy_from_user(to, from, n)
+#define __copy_to_user(to, from, n) copy_to_user(to, from, n)
+
+/*
+ * Copy a null terminated string from userspace.
+ */
+
+static inline long
+strncpy_from_user(char *dst, const char *src, long count)
+{
+ long res;
+ if (count == 0) return count;
+ __asm__ __volatile__
+ ("1: movesb (%2)+,%%d0\n"
+ "12:moveb %%d0,(%1)+\n"
+ " jeq 2f\n"
+ " subql #1,%3\n"
+ " jne 1b\n"
+ "2: subl %3,%0\n"
+ "3:\n"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "4: movel %4,%0\n"
+ " jra 3b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 1b,4b\n"
+ " .long 12b,4b\n"
+ ".previous"
+ : "=d"(res), "=a"(dst), "=a"(src), "=d"(count)
+ : "i"(-EFAULT), "0"(count), "1"(dst), "2"(src), "3"(count)
+ : "d0", "memory");
+ return res;
+}
+
+/*
+ * Return the size of a string (including the ending 0)
+ *
+ * Return 0 on exception, a value greater than N if too long
+ */
+static inline long strnlen_user(const char *src, long n)
+{
+ long res;
+
+ res = -(long)src;
+ __asm__ __volatile__
+ ("1:\n"
+ " tstl %2\n"
+ " jeq 3f\n"
+ "2: movesb (%1)+,%%d0\n"
+ "22:\n"
+ " subql #1,%2\n"
+ " tstb %%d0\n"
+ " jne 1b\n"
+ " jra 4f\n"
+ "3:\n"
+ " addql #1,%0\n"
+ "4:\n"
+ " addl %1,%0\n"
+ "5:\n"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "6: moveq %3,%0\n"
+ " jra 5b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 2b,6b\n"
+ " .long 22b,6b\n"
+ ".previous"
+ : "=d"(res), "=a"(src), "=d"(n)
+ : "i"(0), "0"(res), "1"(src), "2"(n)
+ : "d0");
+ return res;
+}
+
+#define strlen_user(str) strnlen_user(str, 32767)
+
+/*
+ * Zero Userspace
+ */
+
+static inline unsigned long
+clear_user(void *to, unsigned long n)
+{
+ __asm__ __volatile__
+ (" tstl %1\n"
+ " jeq 3f\n"
+ "1: movesl %3,(%0)+\n"
+ "2: subql #1,%1\n"
+ " jne 1b\n"
+ "3: movel %2,%1\n"
+ " bclr #1,%1\n"
+ " jeq 4f\n"
+ "24:movesw %3,(%0)+\n"
+ "4: bclr #0,%1\n"
+ " jeq 5f\n"
+ "25:movesb %3,(%0)+\n"
+ "5:\n"
+ ".section .fixup,\"ax\"\n"
+ " .even\n"
+ "61:addql #1,%1\n"
+ "6: lsll #2,%1\n"
+ " addl %2,%1\n"
+ " jra 5b\n"
+ "7: addql #2,%1\n"
+ " jra 5b\n"
+ "8: addql #1,%1\n"
+ " jra 5b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ " .align 4\n"
+ " .long 1b,61b\n"
+ " .long 2b,6b\n"
+ " .long 3b,61b\n"
+ " .long 24b,7b\n"
+ " .long 4b,7b\n"
+ " .long 25b,8b\n"
+ " .long 5b,8b\n"
+ ".previous"
+ : "=a"(to), "=d"(n)
+ : "r"(n & 3), "r"(0), "0"(to), "1"(n/4));
+ return n;
+}
+
+#endif /* _M68K_UACCESS_H */
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.