2 * Copyright 2004-2009 Analog Devices Inc.
4 * Licensed under the GPL-2 or later.
6 * Based on: include/asm-m68knommu/uaccess.h
9 #ifndef __BLACKFIN_UACCESS_H
10 #define __BLACKFIN_UACCESS_H
13 * User space memory access functions
15 #include <linux/sched.h>
17 #include <linux/string.h>
19 #include <asm/segment.h>
20 #include <asm/sections.h>
22 #define get_ds() (KERNEL_DS)
23 #define get_fs() (current_thread_info()->addr_limit)
25 static inline void set_fs(mm_segment_t fs)
27 current_thread_info()->addr_limit = fs;
30 #define segment_eq(a,b) ((a) == (b))
33 #define VERIFY_WRITE 1
35 #define access_ok(type, addr, size) _access_ok((unsigned long)(addr), (size))
37 static inline int is_in_rom(unsigned long addr)
40 * What we are really trying to do is determine if addr is
41 * in an allocated kernel memory region. If not then assume
42 * we cannot free it or otherwise de-allocate it. Ideally
43 * we could restrict this to really being in a ROM or flash,
44 * but that would need to be done on a board by board basis,
47 if ((addr < _ramstart) || (addr >= _ramend))
50 /* Default case, not in ROM */
55 * The fs value determines whether argument validity checking should be
56 * performed or not. If get_fs() == USER_DS, checking is performed, with
57 * get_fs() == KERNEL_DS, checking is bypassed.
60 #ifndef CONFIG_ACCESS_CHECK
61 static inline int _access_ok(unsigned long addr, unsigned long size) { return 1; }
63 extern int _access_ok(unsigned long addr, unsigned long size);
67 * The exception table consists of pairs of addresses: the first is the
68 * address of an instruction that is allowed to fault, and the second is
69 * the address at which the program should continue. No registers are
70 * modified, so it is entirely up to the continuation code to figure out
73 * All the routines below use bits of fixup code that are out of line
74 * with the main instruction path. This means when everything is well,
75 * we don't even have to jump over them. Further, they do not intrude
76 * on our cache or tlb entries.
79 struct exception_table_entry {
80 unsigned long insn, fixup;
84 * These are the main single-value transfer routines. They automatically
85 * use the right size if we just have the right pointer type.
88 #define put_user(x,p) \
91 typeof(*(p)) _x = (x); \
92 typeof(*(p)) *_p = (p); \
93 if (!access_ok(VERIFY_WRITE, _p, sizeof(*(_p)))) {\
97 switch (sizeof (*(_p))) { \
99 __put_user_asm(_x, _p, B); \
102 __put_user_asm(_x, _p, W); \
105 __put_user_asm(_x, _p, ); \
109 _xl = ((long *)&_x)[0]; \
110 _xh = ((long *)&_x)[1]; \
111 __put_user_asm(_xl, ((long *)_p)+0, ); \
112 __put_user_asm(_xh, ((long *)_p)+1, ); \
115 _err = __put_user_bad(); \
122 #define __put_user(x,p) put_user(x,p)
123 static inline int bad_user_access_length(void)
125 panic("bad_user_access_length");
129 #define __put_user_bad() (printk(KERN_INFO "put_user_bad %s:%d %s\n",\
130 __FILE__, __LINE__, __func__),\
131 bad_user_access_length(), (-EFAULT))
134 * Tell gcc we read from memory instead of writing: this is because
135 * we do not write to any memory gcc knows about, so there are no
139 #define __ptr(x) ((unsigned long *)(x))
141 #define __put_user_asm(x,p,bhw) \
142 __asm__ (#bhw"[%1] = %0;\n\t" \
144 :"d" (x),"a" (__ptr(p)) : "memory")
146 #define get_user(x, ptr) \
149 unsigned long _val = 0; \
150 const typeof(*(ptr)) __user *_p = (ptr); \
151 const size_t ptr_size = sizeof(*(_p)); \
152 if (likely(access_ok(VERIFY_READ, _p, ptr_size))) { \
153 BUILD_BUG_ON(ptr_size >= 8); \
154 switch (ptr_size) { \
156 __get_user_asm(_val, _p, B,(Z)); \
159 __get_user_asm(_val, _p, W,(Z)); \
162 __get_user_asm(_val, _p, , ); \
167 x = (typeof(*(ptr)))_val; \
171 #define __get_user(x,p) get_user(x,p)
173 #define __get_user_bad() (bad_user_access_length(), (-EFAULT))
175 #define __get_user_asm(x, ptr, bhw, option) \
177 __asm__ __volatile__ ( \
178 "%0 =" #bhw "[%1]" #option ";" \
180 : "a" (__ptr(ptr))); \
183 #define __copy_from_user(to, from, n) copy_from_user(to, from, n)
184 #define __copy_to_user(to, from, n) copy_to_user(to, from, n)
185 #define __copy_to_user_inatomic __copy_to_user
186 #define __copy_from_user_inatomic __copy_from_user
188 #define copy_to_user_ret(to,from,n,retval) ({ if (copy_to_user(to,from,n))\
191 #define copy_from_user_ret(to,from,n,retval) ({ if (copy_from_user(to,from,n))\
194 static inline unsigned long __must_check
195 copy_from_user(void *to, const void __user *from, unsigned long n)
197 if (access_ok(VERIFY_READ, from, n))
204 static inline unsigned long __must_check
205 copy_to_user(void *to, const void __user *from, unsigned long n)
207 if (access_ok(VERIFY_WRITE, to, n))
215 * Copy a null terminated string from userspace.
218 static inline long __must_check
219 strncpy_from_user(char *dst, const char *src, long count)
222 if (!access_ok(VERIFY_READ, src, 1))
224 strncpy(dst, src, count);
225 for (tmp = dst; *tmp && count > 0; tmp++, count--) ;
230 * Get the size of a string in user space.
231 * src: The string to measure
232 * n: The maximum valid length
234 * Get the size of a NUL-terminated string in user space.
236 * Returns the size of the string INCLUDING the terminating NUL.
237 * On exception, returns 0.
238 * If the string is too long, returns a value greater than n.
240 static inline long __must_check strnlen_user(const char *src, long n)
242 if (!access_ok(VERIFY_READ, src, 1))
244 return strnlen(src, n) + 1;
247 static inline long __must_check strlen_user(const char *src)
249 if (!access_ok(VERIFY_READ, src, 1))
251 return strlen(src) + 1;
258 static inline unsigned long __must_check
259 __clear_user(void *to, unsigned long n)
261 if (!access_ok(VERIFY_WRITE, to, n))
267 #define clear_user(to, n) __clear_user(to, n)
269 /* How to interpret these return values:
270 * CORE: can be accessed by core load or dma memcpy
271 * CORE_ONLY: can only be accessed by core load
272 * DMA: can only be accessed by dma memcpy
273 * IDMA: can only be accessed by interprocessor dma memcpy (BF561)
274 * ITEST: can be accessed by isram memcpy or dma memcpy
277 BFIN_MEM_ACCESS_CORE = 0,
278 BFIN_MEM_ACCESS_CORE_ONLY,
280 BFIN_MEM_ACCESS_IDMA,
281 BFIN_MEM_ACCESS_ITEST,
284 * bfin_mem_access_type() - what kind of memory access is required
285 * @addr: the address to check
286 * @size: number of bytes needed
287 * @return: <0 is error, >=0 is BFIN_MEM_ACCESS_xxx enum (see above)
289 int bfin_mem_access_type(unsigned long addr, unsigned long size);
291 #endif /* _BLACKFIN_UACCESS_H */