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authorRalf Baechle <ralf@linux-mips.org>2001-01-10 05:27:25 +0000
committerRalf Baechle <ralf@linux-mips.org>2001-01-10 05:27:25 +0000
commitc9c06167e7933d93a6e396174c68abf242294abb (patch)
treed9a8bb30663e9a3405a1ef37ffb62bc14b9f019f /include/asm-parisc/uaccess.h
parentf79e8cc3c34e4192a3e5ef4cc9c6542fdef703c0 (diff)
Merge with Linux 2.4.0-test12.
Diffstat (limited to 'include/asm-parisc/uaccess.h')
-rw-r--r--include/asm-parisc/uaccess.h189
1 files changed, 189 insertions, 0 deletions
diff --git a/include/asm-parisc/uaccess.h b/include/asm-parisc/uaccess.h
new file mode 100644
index 000000000..70e834f12
--- /dev/null
+++ b/include/asm-parisc/uaccess.h
@@ -0,0 +1,189 @@
+#ifndef __PARISC_UACCESS_H
+#define __PARISC_UACCESS_H
+
+/*
+ * User space memory access functions
+ */
+#include <linux/sched.h>
+#include <asm/page.h>
+#include <asm/system.h>
+#include <asm/cache.h>
+
+#define VERIFY_READ 0
+#define VERIFY_WRITE 1
+
+#define KERNEL_DS ((mm_segment_t){0})
+#define USER_DS ((mm_segment_t){1})
+
+#define segment_eq(a,b) ((a).seg == (b).seg)
+
+#define get_ds() (KERNEL_DS)
+#define get_fs() (current->addr_limit)
+#define set_fs(x) (current->addr_limit = (x))
+
+/*
+ * Note that since kernel addresses are in a separate address space on
+ * parisc, we don't need to do anything for access_ok() or verify_area().
+ * We just let the page fault handler do the right thing. This also means
+ * that put_user is the same as __put_user, etc.
+ */
+
+#define access_ok(type,addr,size) (1)
+#define verify_area(type,addr,size) (0)
+
+#define put_user __put_user
+#define get_user __get_user
+
+/*
+ * The exception table contains two values: the first is an address
+ * for an instruction that is allowed to fault, and the second is
+ * the number of bytes to skip if a fault occurs. We also support in
+ * two bit flags: 0x2 tells the exception handler to clear register
+ * r9 and 0x1 tells the exception handler to put -EFAULT in r8.
+ * This allows us to handle the simple cases for put_user and
+ * get_user without having to have .fixup sections.
+ */
+
+struct exception_table_entry {
+ unsigned long addr; /* address of insn that is allowed to fault. */
+ int skip; /* pcoq skip | r9 clear flag | r8 -EFAULT flag */
+};
+
+extern const struct exception_table_entry
+ *search_exception_table(unsigned long addr);
+
+#define __get_user(x,ptr) \
+({ \
+ register long __gu_err __asm__ ("r8") = 0; \
+ register long __gu_val __asm__ ("r9") = 0; \
+ \
+ if (segment_eq(get_fs(),KERNEL_DS)) { \
+ switch (sizeof(*(ptr))) { \
+ case 1: __get_kernel_asm("ldb",ptr); break; \
+ case 2: __get_kernel_asm("ldh",ptr); break; \
+ case 4: __get_kernel_asm("ldw",ptr); break; \
+ case 8: __get_kernel_asm("ldd",ptr); break; \
+ default: BUG(); break; \
+ } \
+ } \
+ else { \
+ switch (sizeof(*(ptr))) { \
+ case 1: __get_user_asm("ldb",ptr); break; \
+ case 2: __get_user_asm("ldh",ptr); break; \
+ case 4: __get_user_asm("ldw",ptr); break; \
+ case 8: __get_user_asm("ldd",ptr); break; \
+ default: BUG(); break; \
+ } \
+ } \
+ \
+ (x) = (__typeof__(*(ptr))) __gu_val; \
+ __gu_err; \
+})
+
+#define __get_kernel_asm(ldx,ptr) \
+ __asm__("\n1:\t" ldx "\t0(%2),%0\n" \
+ "2:\n" \
+ "\t.section __ex_table,\"a\"\n" \
+ "\t.word\t1b\n" \
+ "\t.word\t(2b-1b)+3\n" \
+ "\t.previous" \
+ : "=r"(__gu_val), "=r"(__gu_err) \
+ : "r"(ptr), "1"(__gu_err));
+
+#define __get_user_asm(ldx,ptr) \
+ __asm__("\n1:\t" ldx "\t0(%%sr3,%2),%0\n" \
+ "2:\n" \
+ "\t.section __ex_table,\"a\"\n" \
+ "\t.word\t1b\n" \
+ "\t.word\t(2b-1b)+3\n" \
+ "\t.previous" \
+ : "=r"(__gu_val), "=r"(__gu_err) \
+ : "r"(ptr), "1"(__gu_err));
+
+
+#define __put_user(x,ptr) \
+({ \
+ register long __pu_err __asm__ ("r8") = 0; \
+ \
+ if (segment_eq(get_fs(),KERNEL_DS)) { \
+ switch (sizeof(*(ptr))) { \
+ case 1: __put_kernel_asm("stb",x,ptr); break; \
+ case 2: __put_kernel_asm("sth",x,ptr); break; \
+ case 4: __put_kernel_asm("stw",x,ptr); break; \
+ case 8: __put_kernel_asm("std",x,ptr); break; \
+ default: BUG(); break; \
+ } \
+ } \
+ else { \
+ switch (sizeof(*(ptr))) { \
+ case 1: __put_user_asm("stb",x,ptr); break; \
+ case 2: __put_user_asm("sth",x,ptr); break; \
+ case 4: __put_user_asm("stw",x,ptr); break; \
+ case 8: __put_user_asm("std",x,ptr); break; \
+ default: BUG(); break; \
+ } \
+ } \
+ \
+ __pu_err; \
+})
+
+/*
+ * The "__put_user/kernel_asm()" macros tell gcc they read from memory
+ * instead of writing. This is because they do not write to any memory
+ * gcc knows about, so there are no aliasing issues.
+ */
+
+#define __put_kernel_asm(stx,x,ptr) \
+ __asm__ __volatile__ ( \
+ "\n1:\t" stx "\t%2,0(%1)\n" \
+ "2:\n" \
+ "\t.section __ex_table,\"a\"\n" \
+ "\t.word\t1b\n" \
+ "\t.word\t(2b-1b)+1\n" \
+ "\t.previous" \
+ : "=r"(__pu_err) \
+ : "r"(ptr), "r"(x), "0"(__pu_err))
+
+#define __put_user_asm(stx,x,ptr) \
+ __asm__ __volatile__ ( \
+ "\n1:\t" stx "\t%2,0(%%sr3,%1)\n" \
+ "2:\n" \
+ "\t.section __ex_table,\"a\"\n" \
+ "\t.word\t1b\n" \
+ "\t.word\t(2b-1b)+1\n" \
+ "\t.previous" \
+ : "=r"(__pu_err) \
+ : "r"(ptr), "r"(x), "0"(__pu_err))
+
+
+/*
+ * Complex access routines -- external declarations
+ */
+
+extern unsigned long lcopy_to_user(void *, const void *, unsigned long);
+extern unsigned long lcopy_from_user(void *, const void *, unsigned long);
+extern long lstrncpy_from_user(char *, const char *, long);
+extern unsigned lclear_user(void *,unsigned long);
+extern long lstrnlen_user(const char *,long);
+
+/*
+ * Complex access routines -- macros
+ */
+
+#define strncpy_from_user lstrncpy_from_user
+#define strnlen_user lstrnlen_user
+#define strlen_user(str) lstrnlen_user(str, 0x7fffffffL)
+#define clear_user lclear_user
+
+#define copy_from_user lcopy_from_user
+#define __copy_from_user lcopy_from_user
+#define copy_to_user lcopy_to_user
+#define __copy_to_user lcopy_to_user
+
+#define copy_to_user_ret(to,from,n,retval) \
+ ({ if (lcopy_to_user(to,from,n)) return retval; })
+
+#define copy_from_user_ret(to,from,n,retval) \
+ ({ if (lcopy_from_user(to,from,n)) return retval; })
+
+#endif /* __PARISC_UACCESS_H */