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()
53 	if (offs > n.left)  in membuf_at()
54 		offs = n.left;  in membuf_at()
56 	n.left -= offs;  in membuf_at()
61 /* current s->p must be aligned for v; v must be a scalar */
65         if (__s->left) {				\
68 		if (unlikely(__size > __s->left)) {	\
69 			__size = __s->left;		\
70 			memcpy(__s->p, &__v, __size);	\
72 			*(typeof(__v + 0) *)__s->p = __v;	\
74 		__s->p += __size;			\
75 		__s->left -= __size;			\
77 	__s->left;})
80  * user_regset_active_fn - type of @active function in &struct user_regset
84  * Return -%ENODEV if not available on the hardware found.
102  * user_regset_set_fn - type of @set function in &struct user_regset
107  * @kbuf:	if not %NULL, a kernel-space pointer to copy from
108  * @ubuf:	if @kbuf is %NULL, a user-space pointer to copy from
110  * Store register values.  Return %0 on success; -%EIO or -%ENODEV
112  * bytes, but must be properly aligned.  If @kbuf is non-null, that
114  * ubuf gives a userland pointer to access directly, and an -%EFAULT
123  * user_regset_writeback_fn - type of @writeback function in &struct user_regset
139  * Return %0 on success or if there was nothing to do, -%EFAULT for
140  * a memory problem (bad stack pointer or whatever), or -%EIO for a
148  * struct user_regset - accessible thread CPU state
162  * similar slots, given by @n.  Each slot is @size bytes, and aligned to
163  * @align bytes (which is at least @size).  For dynamically-sized
180  * The @pos argument must be aligned according to @align; the @count
195  * part of the per-machine ELF formats userland knows about.  In
213  * struct user_regset_view - available regsets
225  * might refer to the same machine-specific state in the thread.  For
226  * example, a 32-bit thread's state could be examined from the 32-bit
227  * view or from the 64-bit view.  Either method reaches the same thread
241  * implementation is machine-dependent but its interface is universal.
244  * task_user_regset_view - Return the process's native regset view.
263 				     : min(*count, end_pos - *pos));  in user_regset_copyin()
264 		data += *pos - start_pos;  in user_regset_copyin()
269 			return -EFAULT;  in user_regset_copyin()
273 		*count -= copy;  in user_regset_copyin()
290 				     : min(*count, end_pos - *pos));  in user_regset_copyin_ignore()
296 		*count -= copy;  in user_regset_copyin_ignore()
316  * copy_regset_from_user - store into thread's user_regset data from user memory
319  * @setno:	index in @view->regsets
322  * @data:	user-mode pointer to copy from
330 	const struct user_regset *regset = &view->regsets[setno];  in copy_regset_from_user()
332 	if (!regset->set)  in copy_regset_from_user()
333 		return -EOPNOTSUPP;  in copy_regset_from_user()
336 		return -EFAULT;  in copy_regset_from_user()
338 	return regset->set(target, regset, offset, size, NULL, data);  in copy_regset_from_user()