Commit 480402e1 authored by Al Viro's avatar Al Viro
Browse files

untangling process_vm_..., part 1 



we want to massage it to use of iov_iter.  This one is an equivalent
transformation - just introduce a local variable mirroring
lvec + *lvec_current.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent ec695579

mm/process_vm_access.c

+9 −5
Original line number Diff line number Diff line
@@ -60,6 +60,7 @@ static int process_vm_rw_pages(struct task_struct *task, 
	int ret;

	ssize_t bytes_to_copy;

	ssize_t rc = 0;

	const struct iovec *iov = lvec + *lvec_current;



	*bytes_copied = 0;
@@ -81,8 +82,10 @@ static int process_vm_rw_pages(struct task_struct *task, 
	     pgs_copied++) {

		/* Make sure we have a non zero length iovec */

		while (*lvec_current < lvec_cnt

		       && lvec[*lvec_current].iov_len == 0)

		       && iov->iov_len == 0) {

			iov++;

			(*lvec_current)++;

		}

		if (*lvec_current == lvec_cnt)

			break;
@@ -94,18 +97,18 @@ static int process_vm_rw_pages(struct task_struct *task, 
		bytes_to_copy = min_t(ssize_t, PAGE_SIZE - start_offset,

				      len - *bytes_copied);

		bytes_to_copy = min_t(ssize_t, bytes_to_copy,

				      lvec[*lvec_current].iov_len

				      iov->iov_len

				      - *lvec_offset);



		target_kaddr = kmap(process_pages[pgs_copied]) + start_offset;



		if (vm_write)

			ret = copy_from_user(target_kaddr,

					     lvec[*lvec_current].iov_base

					     iov->iov_base

					     + *lvec_offset,

					     bytes_to_copy);

		else

			ret = copy_to_user(lvec[*lvec_current].iov_base

			ret = copy_to_user(iov->iov_base

					   + *lvec_offset,

					   target_kaddr, bytes_to_copy);

		kunmap(process_pages[pgs_copied]);
@@ -117,12 +120,13 @@ static int process_vm_rw_pages(struct task_struct *task, 
		}

		*bytes_copied += bytes_to_copy;

		*lvec_offset += bytes_to_copy;

		if (*lvec_offset == lvec[*lvec_current].iov_len) {

		if (*lvec_offset == iov->iov_len) {

			/*

			 * Need to copy remaining part of page into the

			 * next iovec if there are any bytes left in page

			 */

			(*lvec_current)++;

			iov++;

			*lvec_offset = 0;

			start_offset = (start_offset + bytes_to_copy)

				% PAGE_SIZE;