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: Al Viro <viro@zeniv.linux.org.uk>

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: Al Viro <viro@zeniv.linux.org.uk>
Al Viro
1 parent ec69557982
Showing 1 changed file with 9 additions and 5 deletions Side-by-side Diff
mm/process_vm_access.c
@@ -60,6 +60,7 @@
 	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 @@
 	     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 @@
 		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 @@
 		}
 		*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;
...	...	@@ -60,6 +60,7 @@
60	60	int ret;
61	61	ssize_t bytes_to_copy;
62	62	ssize_t rc = 0;
	63	+ const struct iovec iov = lvec + lvec_current;
63	64
64	65	*bytes_copied = 0;
65	66
66	67
...	...	@@ -81,8 +82,10 @@
81	82	pgs_copied++) {
82	83	/* Make sure we have a non zero length iovec */
83	84	while (*lvec_current < lvec_cnt
84		- && lvec[*lvec_current].iov_len == 0)
	85	+ && iov->iov_len == 0) {
	86	+ iov++;
85	87	(*lvec_current)++;
	88	+ }
86	89	if (*lvec_current == lvec_cnt)
87	90	break;
88	91
89	92
90	93
...	...	@@ -94,18 +97,18 @@
94	97	bytes_to_copy = min_t(ssize_t, PAGE_SIZE - start_offset,
95	98	len - *bytes_copied);
96	99	bytes_to_copy = min_t(ssize_t, bytes_to_copy,
97		- lvec[*lvec_current].iov_len
	100	+ iov->iov_len
98	101	- *lvec_offset);
99	102
100	103	target_kaddr = kmap(process_pages[pgs_copied]) + start_offset;
101	104
102	105	if (vm_write)
103	106	ret = copy_from_user(target_kaddr,
104		- lvec[*lvec_current].iov_base
	107	+ iov->iov_base
105	108	+ *lvec_offset,
106	109	bytes_to_copy);
107	110	else
108		- ret = copy_to_user(lvec[*lvec_current].iov_base
	111	+ ret = copy_to_user(iov->iov_base
109	112	+ *lvec_offset,
110	113	target_kaddr, bytes_to_copy);
111	114	kunmap(process_pages[pgs_copied]);
112	115
...	...	@@ -117,12 +120,13 @@
117	120	}
118	121	*bytes_copied += bytes_to_copy;
119	122	*lvec_offset += bytes_to_copy;
120		- if (lvec_offset == lvec[lvec_current].iov_len) {
	123	+ if (*lvec_offset == iov->iov_len) {
121	124	/*
122	125	* Need to copy remaining part of page into the
123	126	* next iovec if there are any bytes left in page
124	127	*/
125	128	(*lvec_current)++;
	129	+ iov++;
126	130	*lvec_offset = 0;
127	131	start_offset = (start_offset + bytes_to_copy)
128	132	% PAGE_SIZE;