ceph: drop special-casing for ITER_PIPE in ceph_sync_read

This special casing was added in 7ce469a53e71 (ceph: fix splice
read for no Fc capability case). The confirm callback for ITER_PIPE
expects that the page is Uptodate and returns an error otherwise.

A simpler workaround is just to use the Uptodate bit, which has no
meaning for anonymous pages. Rip out the special casing for ITER_PIPE
and just SetPageUptodate before we copy to the iter.

Cc: John Hubbard <jhubbard@nvidia.com>
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index fb3ea71..ed8fbfe 100644 (file)
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -863,6 +863,8 @@ static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *to,
                size_t page_off;
                u64 i_size;
                bool more;
+               int idx;
+               size_t left;
 
                req = ceph_osdc_new_request(osdc, &ci->i_layout,
                                        ci->i_vino, off, &len, 0, 1,
@@ -876,29 +878,13 @@ static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *to,
 
                more = len < iov_iter_count(to);
 
-               if (unlikely(iov_iter_is_pipe(to))) {
-                       ret = iov_iter_get_pages_alloc(to, &pages, len,
-                                                      &page_off);
-                       if (ret <= 0) {
-                               ceph_osdc_put_request(req);
-                               ret = -ENOMEM;
-                               break;
-                       }
-                       num_pages = DIV_ROUND_UP(ret + page_off, PAGE_SIZE);
-                       if (ret < len) {
-                               len = ret;
-                               osd_req_op_extent_update(req, 0, len);
-                               more = false;
-                       }
-               } else {
-                       num_pages = calc_pages_for(off, len);
-                       page_off = off & ~PAGE_MASK;
-                       pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
-                       if (IS_ERR(pages)) {
-                               ceph_osdc_put_request(req);
-                               ret = PTR_ERR(pages);
-                               break;
-                       }
+               num_pages = calc_pages_for(off, len);
+               page_off = off & ~PAGE_MASK;
+               pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
+               if (IS_ERR(pages)) {
+                       ceph_osdc_put_request(req);
+                       ret = PTR_ERR(pages);
+                       break;
                }
 
                osd_req_op_extent_osd_data_pages(req, 0, pages, len, page_off,
@@ -929,32 +915,23 @@ static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *to,
                        ret += zlen;
                }
 
-               if (unlikely(iov_iter_is_pipe(to))) {
-                       if (ret > 0) {
-                               iov_iter_advance(to, ret);
-                               off += ret;
-                       } else {
-                               iov_iter_advance(to, 0);
-                       }
-                       ceph_put_page_vector(pages, num_pages, false);
-               } else {
-                       int idx = 0;
-                       size_t left = ret > 0 ? ret : 0;
-                       while (left > 0) {
-                               size_t len, copied;
-                               page_off = off & ~PAGE_MASK;
-                               len = min_t(size_t, left, PAGE_SIZE - page_off);
-                               copied = copy_page_to_iter(pages[idx++],
-                                                          page_off, len, to);
-                               off += copied;
-                               left -= copied;
-                               if (copied < len) {
-                                       ret = -EFAULT;
-                                       break;
-                               }
+               idx = 0;
+               left = ret > 0 ? ret : 0;
+               while (left > 0) {
+                       size_t len, copied;
+                       page_off = off & ~PAGE_MASK;
+                       len = min_t(size_t, left, PAGE_SIZE - page_off);
+                       SetPageUptodate(pages[idx]);
+                       copied = copy_page_to_iter(pages[idx++],
+                                                  page_off, len, to);
+                       off += copied;
+                       left -= copied;
+                       if (copied < len) {
+                               ret = -EFAULT;
+                               break;
                        }
-                       ceph_release_page_vector(pages, num_pages);
                }
+               ceph_release_page_vector(pages, num_pages);
 
                if (ret < 0) {
                        if (ret == -EBLACKLISTED)