ceph_sync_read: stop poking into iov_iter guts
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index c9a24ba..672b0fe 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -418,7 +418,7 @@
struct page **pages;
u64 off = iocb->ki_pos;
int num_pages, ret;
- size_t len = i->count;
+ size_t len = iov_iter_count(i);
dout("sync_read on file %p %llu~%u %s\n", file, off,
(unsigned)len,
@@ -436,25 +436,26 @@
if (file->f_flags & O_DIRECT) {
while (iov_iter_count(i)) {
- void __user *data = i->iov[0].iov_base + i->iov_offset;
- size_t len = i->iov[0].iov_len - i->iov_offset;
+ size_t start;
+ ssize_t n;
- num_pages = calc_pages_for((unsigned long)data, len);
- pages = ceph_get_direct_page_vector(data,
- num_pages, true);
- if (IS_ERR(pages))
- return PTR_ERR(pages);
+ n = iov_iter_get_pages_alloc(i, &pages, INT_MAX, &start);
+ if (n < 0)
+ return n;
- ret = striped_read(inode, off, len,
+ num_pages = (n + start + PAGE_SIZE - 1) / PAGE_SIZE;
+
+ ret = striped_read(inode, off, n,
pages, num_pages, checkeof,
- 1, (unsigned long)data & ~PAGE_MASK);
+ 1, start);
+
ceph_put_page_vector(pages, num_pages, true);
if (ret <= 0)
break;
off += ret;
iov_iter_advance(i, ret);
- if (ret < len)
+ if (ret < n)
break;
}
} else {
@@ -466,25 +467,14 @@
num_pages, checkeof, 0, 0);
if (ret > 0) {
int l, k = 0;
- size_t left = len = ret;
+ size_t left = ret;
while (left) {
- void __user *data = i->iov[0].iov_base
- + i->iov_offset;
- l = min(i->iov[0].iov_len - i->iov_offset,
- left);
-
- ret = ceph_copy_page_vector_to_user(&pages[k],
- data, off,
- l);
- if (ret > 0) {
- iov_iter_advance(i, ret);
- left -= ret;
- off += ret;
- k = calc_pages_for(iocb->ki_pos,
- len - left + 1) - 1;
- BUG_ON(k >= num_pages && left);
- } else
+ int copy = min_t(size_t, PAGE_SIZE, left);
+ l = copy_page_to_iter(pages[k++], 0, copy, i);
+ off += l;
+ left -= l;
+ if (l < copy)
break;
}
}