process_vm_access: switch to iov_iter
instead of keeping its pieces in separate variables and passing
pointers to all of them...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c
index 4bbd495..1e3c811 100644
--- a/mm/process_vm_access.c
+++ b/mm/process_vm_access.c
@@ -45,9 +45,7 @@
unsigned long pa,
unsigned long start_offset,
unsigned long len,
- const struct iovec **iovp,
- unsigned long *left,
- size_t *lvec_offset,
+ struct iov_iter *iter,
int vm_write,
unsigned int nr_pages_to_copy,
ssize_t *bytes_copied)
@@ -59,7 +57,7 @@
int ret;
ssize_t bytes_to_copy;
ssize_t rc = 0;
- const struct iovec *iov = *iovp;
+ const struct iovec *iov = iter->iov;
*bytes_copied = 0;
@@ -77,14 +75,14 @@
/* Do the copy for each page */
for (pgs_copied = 0;
- (pgs_copied < nr_pages_to_copy) && *left;
+ (pgs_copied < nr_pages_to_copy) && iter->nr_segs;
pgs_copied++) {
/* Make sure we have a non zero length iovec */
- while (*left && iov->iov_len == 0) {
+ while (iter->nr_segs && iov->iov_len == 0) {
iov++;
- (*left)--;
+ iter->nr_segs--;
}
- if (!*left)
+ if (!iter->nr_segs)
break;
/*
@@ -96,18 +94,18 @@
len - *bytes_copied);
bytes_to_copy = min_t(ssize_t, bytes_to_copy,
iov->iov_len
- - *lvec_offset);
+ - iter->iov_offset);
target_kaddr = kmap(process_pages[pgs_copied]) + start_offset;
if (vm_write)
ret = copy_from_user(target_kaddr,
iov->iov_base
- + *lvec_offset,
+ + iter->iov_offset,
bytes_to_copy);
else
ret = copy_to_user(iov->iov_base
- + *lvec_offset,
+ + iter->iov_offset,
target_kaddr, bytes_to_copy);
kunmap(process_pages[pgs_copied]);
if (ret) {
@@ -117,15 +115,15 @@
goto end;
}
*bytes_copied += bytes_to_copy;
- *lvec_offset += bytes_to_copy;
- if (*lvec_offset == iov->iov_len) {
+ iter->iov_offset += bytes_to_copy;
+ if (iter->iov_offset == iov->iov_len) {
/*
* Need to copy remaining part of page into the
* next iovec if there are any bytes left in page
*/
- (*left)--;
+ iter->nr_segs--;
iov++;
- *lvec_offset = 0;
+ iter->iov_offset = 0;
start_offset = (start_offset + bytes_to_copy)
% PAGE_SIZE;
if (start_offset)
@@ -147,7 +145,7 @@
put_page(process_pages[j]);
}
- *iovp = iov;
+ iter->iov = iov;
return rc;
}
@@ -172,9 +170,7 @@
*/
static int process_vm_rw_single_vec(unsigned long addr,
unsigned long len,
- const struct iovec **iovp,
- unsigned long *left,
- size_t *lvec_offset,
+ struct iov_iter *iter,
struct page **process_pages,
struct mm_struct *mm,
struct task_struct *task,
@@ -198,14 +194,12 @@
return 0;
nr_pages = (addr + len - 1) / PAGE_SIZE - addr / PAGE_SIZE + 1;
- while ((nr_pages_copied < nr_pages) && *left) {
+ while ((nr_pages_copied < nr_pages) && iter->nr_segs) {
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, left,
- lvec_offset,
+ start_offset, len, iter,
vm_write, nr_pages_to_copy,
&bytes_copied_loop);
start_offset = 0;
@@ -240,8 +234,7 @@
* return less bytes than expected if an error occurs during the copying
* process.
*/
-static ssize_t process_vm_rw_core(pid_t pid, const struct iovec *lvec,
- unsigned long liovcnt,
+static ssize_t process_vm_rw_core(pid_t pid, struct iov_iter *iter,
const struct iovec *rvec,
unsigned long riovcnt,
unsigned long flags, int vm_write)
@@ -256,8 +249,6 @@
ssize_t bytes_copied = 0;
unsigned long nr_pages = 0;
unsigned long nr_pages_iov;
- unsigned long left = liovcnt;
- size_t iov_l_curr_offset = 0;
ssize_t iov_len;
/*
@@ -312,11 +303,11 @@
goto put_task_struct;
}
- for (i = 0; i < riovcnt && left; i++) {
+ for (i = 0; i < riovcnt && iter->nr_segs; i++) {
rc = process_vm_rw_single_vec(
(unsigned long)rvec[i].iov_base, rvec[i].iov_len,
- &lvec, &left, &iov_l_curr_offset,
- process_pages, mm, task, vm_write, &bytes_copied_loop);
+ iter, process_pages, mm, task, vm_write,
+ &bytes_copied_loop);
bytes_copied += bytes_copied_loop;
if (rc != 0) {
/* If we have managed to copy any data at all then
@@ -365,6 +356,7 @@
struct iovec iovstack_r[UIO_FASTIOV];
struct iovec *iov_l = iovstack_l;
struct iovec *iov_r = iovstack_r;
+ struct iov_iter iter;
ssize_t rc;
if (flags != 0)
@@ -380,13 +372,14 @@
if (rc <= 0)
goto free_iovecs;
+ iov_iter_init(&iter, iov_l, liovcnt, rc, 0);
+
rc = rw_copy_check_uvector(CHECK_IOVEC_ONLY, rvec, riovcnt, UIO_FASTIOV,
iovstack_r, &iov_r);
if (rc <= 0)
goto free_iovecs;
- rc = process_vm_rw_core(pid, iov_l, liovcnt, iov_r, riovcnt, flags,
- vm_write);
+ rc = process_vm_rw_core(pid, &iter, iov_r, riovcnt, flags, vm_write);
free_iovecs:
if (iov_r != iovstack_r)
@@ -426,6 +419,7 @@
struct iovec iovstack_r[UIO_FASTIOV];
struct iovec *iov_l = iovstack_l;
struct iovec *iov_r = iovstack_r;
+ struct iov_iter iter;
ssize_t rc = -EFAULT;
if (flags != 0)
@@ -441,14 +435,14 @@
&iov_l);
if (rc <= 0)
goto free_iovecs;
+ iov_iter_init(&iter, iov_l, liovcnt, rc, 0);
rc = compat_rw_copy_check_uvector(CHECK_IOVEC_ONLY, rvec, riovcnt,
UIO_FASTIOV, iovstack_r,
&iov_r);
if (rc <= 0)
goto free_iovecs;
- rc = process_vm_rw_core(pid, iov_l, liovcnt, iov_r, riovcnt, flags,
- vm_write);
+ rc = process_vm_rw_core(pid, &iter, iov_r, riovcnt, flags, vm_write);
free_iovecs:
if (iov_r != iovstack_r)