Commit dc12d796 authored by Al Viro's avatar Al Viro
Browse files

copy_regset_to_user(): do all copyout at once. 



Turn copy_regset_to_user() into regset_get_alloc() + copy_to_user().
Now all ->get() calls have a kernel buffer as destination.

Note that we'd already eliminated the callers of copy_regset_to_user()
with non-zero offset; now that argument is simply unused.

Uninlined, while we are at it.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 1e56f6d2

include/linux/regset.h

+4 −25
Original line number Diff line number Diff line
@@ -362,31 +362,10 @@ extern int regset_get_alloc(struct task_struct *target, 
			    unsigned int size,

			    void **data);



/**

 * copy_regset_to_user - fetch a thread's user_regset data into user memory

 * @target:	thread to be examined

 * @view:	&struct user_regset_view describing user thread machine state

 * @setno:	index in @view->regsets

 * @offset:	offset into the regset data, in bytes

 * @size:	amount of data to copy, in bytes

 * @data:	user-mode pointer to copy into

 */

static inline int copy_regset_to_user(struct task_struct *target,

extern int copy_regset_to_user(struct task_struct *target,

			       const struct user_regset_view *view,

				      unsigned int setno,

				      unsigned int offset, unsigned int size,

				      void __user *data)

{

	const struct user_regset *regset = &view->regsets[setno];



	if (!regset->get)

		return -EOPNOTSUPP;



	if (!access_ok(data, size))

		return -EFAULT;



	return regset->get(target, regset, offset, size, NULL, data);

}

			       unsigned int setno, unsigned int offset,

			       unsigned int size, void __user *data);



/**

 * copy_regset_from_user - store into thread's user_regset data from user memory

kernel/regset.c

+26 −0
Original line number Diff line number Diff line
@@ -52,3 +52,29 @@ int regset_get_alloc(struct task_struct *target, 
	return __regset_get(target, regset, size, data);

}

EXPORT_SYMBOL(regset_get_alloc);



/**

 * copy_regset_to_user - fetch a thread's user_regset data into user memory

 * @target:	thread to be examined

 * @view:	&struct user_regset_view describing user thread machine state

 * @setno:	index in @view->regsets

 * @offset:	offset into the regset data, in bytes

 * @size:	amount of data to copy, in bytes

 * @data:	user-mode pointer to copy into

 */

int copy_regset_to_user(struct task_struct *target,

			const struct user_regset_view *view,

			unsigned int setno,

			unsigned int offset, unsigned int size,

			void __user *data)

{

	const struct user_regset *regset = &view->regsets[setno];

	void *buf;

	int ret;



	ret = regset_get_alloc(target, regset, size, &buf);

	if (ret > 0)

		ret = copy_to_user(data, buf, ret) ? -EFAULT : 0;

	kfree(buf);

	return ret;

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE