1 /* SPDX-License-Identifier: GPL-2.0-only */
3  * User-mode machine state access
22 	size_t left;  member
27 	if (s->left) {  in membuf_zero()
28 		if (size > s->left)  in membuf_zero()
29 			size = s->left;  in membuf_zero()
30 		memset(s->p, 0, size);  in membuf_zero()
31 		s->p += size;  in membuf_zero()
32 		s->left -= size;  in membuf_zero()
34 	return s->left;  in membuf_zero()
39 	if (s->left) {  in membuf_write()
40 		if (size > s->left)  in membuf_write()
41 			size = s->left;  in membuf_write()
42 		memcpy(s->p, v, size);  in membuf_write()
43 		s->p += size;  in membuf_write()
44 		s->left -= size;  in membuf_write()
46 	return s->left;  in membuf_write()
49 /* current s->p must be aligned for v; v must be a scalar */
53         if (__s->left) {				\
56 		if (unlikely(__size > __s->left)) {	\
57 			__size = __s->left;		\
58 			memcpy(__s->p, &__v, __size);	\
60 			*(typeof(__v + 0) *)__s->p = __v;	\
62 		__s->p += __size;			\
63 		__s->left -= __size;			\
65 	__s->left;})
68  * user_regset_active_fn - type of @active function in &struct user_regset
72  * Return -%ENODEV if not available on the hardware found.
90  * user_regset_set_fn - type of @set function in &struct user_regset
95  * @kbuf:	if not %NULL, a kernel-space pointer to copy from
96  * @ubuf:	if @kbuf is %NULL, a user-space pointer to copy from
98  * Store register values.  Return %0 on success; -%EIO or -%ENODEV
100  * bytes, but must be properly aligned.  If @kbuf is non-null, that
102  * ubuf gives a userland pointer to access directly, and an -%EFAULT
111  * user_regset_writeback_fn - type of @writeback function in &struct user_regset
127  * Return %0 on success or if there was nothing to do, -%EFAULT for
128  * a memory problem (bad stack pointer or whatever), or -%EIO for a
136  * struct user_regset - accessible thread CPU state
150  * similar slots, given by @n.  Each slot is @size bytes, and aligned to
151  * @align bytes (which is at least @size).  For dynamically-sized
168  * The @pos argument must be aligned according to @align; the @count
183  * part of the per-machine ELF formats userland knows about.  In
201  * struct user_regset_view - available regsets
213  * might refer to the same machine-specific state in the thread.  For
214  * example, a 32-bit thread's state could be examined from the 32-bit
215  * view or from the 64-bit view.  Either method reaches the same thread
229  * implementation is machine-dependent but its interface is universal.
232  * task_user_regset_view - Return the process's native regset view.
251 				     : min(*count, end_pos - *pos));  in user_regset_copyin()
252 		data += *pos - start_pos;  in user_regset_copyin()
257 			return -EFAULT;  in user_regset_copyin()
261 		*count -= copy;  in user_regset_copyin()
278 				     : min(*count, end_pos - *pos));  in user_regset_copyin_ignore()
284 		*count -= copy;  in user_regset_copyin_ignore()
304  * copy_regset_from_user - store into thread's user_regset data from user memory
307  * @setno:	index in @view->regsets
310  * @data:	user-mode pointer to copy from
318 	const struct user_regset *regset = &view->regsets[setno];  in copy_regset_from_user()
320 	if (!regset->set)  in copy_regset_from_user()
321 		return -EOPNOTSUPP;  in copy_regset_from_user()
324 		return -EFAULT;  in copy_regset_from_user()
326 	return regset->set(target, regset, offset, size, NULL, data);  in copy_regset_from_user()