orangefs: make pvfs2_inode_read() take iov_iter
... and make the only caller use page-backed iov_iter,
getting rid of kmap/kunmap *and* of the bug with
attempted use of iovec-backed copy_page_to_iter()
on a kernel pointer.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
diff --git a/fs/orangefs/inode.c b/fs/orangefs/inode.c
index 4f7c45a..70d1c19 100644
--- a/fs/orangefs/inode.c
+++ b/fs/orangefs/inode.c
@@ -14,18 +14,20 @@
static int read_one_page(struct page *page)
{
- void *page_data;
int ret;
int max_block;
ssize_t bytes_read = 0;
struct inode *inode = page->mapping->host;
const __u32 blocksize = PAGE_CACHE_SIZE; /* inode->i_blksize */
const __u32 blockbits = PAGE_CACHE_SHIFT; /* inode->i_blkbits */
+ struct iov_iter to;
+ struct bio_vec bv = {.bv_page = page, .bv_len = PAGE_SIZE};
+
+ iov_iter_bvec(&to, ITER_BVEC | READ, &bv, 1, PAGE_SIZE);
gossip_debug(GOSSIP_INODE_DEBUG,
"pvfs2_readpage called with page %p\n",
page);
- page_data = pvfs2_kmap(page);
max_block = ((inode->i_size / blocksize) + 1);
@@ -33,16 +35,12 @@
loff_t blockptr_offset = (((loff_t) page->index) << blockbits);
bytes_read = pvfs2_inode_read(inode,
- (char __user *) page_data,
- blocksize,
+ &to,
&blockptr_offset,
inode->i_size);
}
- /* only zero remaining unread portions of the page data */
- if (bytes_read > 0)
- memset(page_data + bytes_read, 0, blocksize - bytes_read);
- else
- memset(page_data, 0, blocksize);
+ /* this will only zero remaining unread portions of the page data */
+ iov_iter_zero(~0U, &to);
/* takes care of potential aliasing */
flush_dcache_page(page);
if (bytes_read < 0) {
@@ -54,7 +52,6 @@
ClearPageError(page);
ret = 0;
}
- pvfs2_kunmap(page);
/* unlock the page after the ->readpage() routine completes */
unlock_page(page);
return ret;