Commit 1291afc1 authored by Al Viro's avatar Al Viro
Browse files

untangling process_vm_..., part 4 



instead of passing vector size (by value) and index (by reference),
pass the number of elements remaining.  That's all we care about
in these functions by that point.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 12e3004e

mm/process_vm_access.c

+13 −16
Original line number Diff line number Diff line
@@ -46,8 +46,7 @@ static int process_vm_rw_pages(struct task_struct *task, 
			       unsigned long start_offset,

			       unsigned long len,

			       const struct iovec **iovp,

			       unsigned long lvec_cnt,

			       unsigned long *lvec_current,

			       unsigned long *left,

			       size_t *lvec_offset,

			       int vm_write,

			       unsigned int nr_pages_to_copy,
@@ -78,15 +77,14 @@ static int process_vm_rw_pages(struct task_struct *task, 


	/* Do the copy for each page */

	for (pgs_copied = 0;

	     (pgs_copied < nr_pages_to_copy) && (*lvec_current < lvec_cnt);

	     (pgs_copied < nr_pages_to_copy) && *left;

	     pgs_copied++) {

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

		while (*lvec_current < lvec_cnt

		       && iov->iov_len == 0) {

		while (*left && iov->iov_len == 0) {

			iov++;

			(*lvec_current)++;

			(*left)--;

		}

		if (*lvec_current == lvec_cnt)

		if (!*left)

			break;



		/*
@@ -125,7 +123,7 @@ static int process_vm_rw_pages(struct task_struct *task, 
			 * Need to copy remaining part of page into the

			 * next iovec if there are any bytes left in page

			 */

			(*lvec_current)++;

			(*left)--;

			iov++;

			*lvec_offset = 0;

			start_offset = (start_offset + bytes_to_copy)
@@ -175,8 +173,7 @@ static int process_vm_rw_pages(struct task_struct *task, 
static int process_vm_rw_single_vec(unsigned long addr,

				    unsigned long len,

				    const struct iovec **iovp,

				    unsigned long lvec_cnt,

				    unsigned long *lvec_current,

				    unsigned long *left,

				    size_t *lvec_offset,

				    struct page **process_pages,

				    struct mm_struct *mm,
@@ -201,14 +198,14 @@ static int process_vm_rw_single_vec(unsigned long addr, 
		return 0;

	nr_pages = (addr + len - 1) / PAGE_SIZE - addr / PAGE_SIZE + 1;



	while ((nr_pages_copied < nr_pages) && (*lvec_current < lvec_cnt)) {

	while ((nr_pages_copied < nr_pages) && *left) {

		nr_pages_to_copy = min(nr_pages - nr_pages_copied,

				       max_pages_per_loop);



		rc = process_vm_rw_pages(task, mm, process_pages, pa,

					 start_offset, len,

					 iovp, lvec_cnt,

					 lvec_current, lvec_offset,

					 iovp, left,

					 lvec_offset,

					 vm_write, nr_pages_to_copy,

					 &bytes_copied_loop);

		start_offset = 0;
@@ -259,7 +256,7 @@ static ssize_t process_vm_rw_core(pid_t pid, const struct iovec *lvec, 
	ssize_t bytes_copied = 0;

	unsigned long nr_pages = 0;

	unsigned long nr_pages_iov;

	unsigned long iov_l_curr_idx = 0;

	unsigned long left = liovcnt;

	size_t iov_l_curr_offset = 0;

	ssize_t iov_len;
@@ -315,10 +312,10 @@ static ssize_t process_vm_rw_core(pid_t pid, const struct iovec *lvec, 
		goto put_task_struct;

	}



	for (i = 0; i < riovcnt && iov_l_curr_idx < liovcnt; i++) {

	for (i = 0; i < riovcnt && left; i++) {

		rc = process_vm_rw_single_vec(

			(unsigned long)rvec[i].iov_base, rvec[i].iov_len,

			&lvec, liovcnt, &iov_l_curr_idx, &iov_l_curr_offset,

			&lvec, &left, &iov_l_curr_offset,

			process_pages, mm, task, vm_write, &bytes_copied_loop);

		bytes_copied += bytes_copied_loop;

		if (rc != 0) {