ceph: use osd_req_op_extent_osd_iter for netfs reads

The netfs layer has already pinned the pages involved before calling
issue_op, so we can just pass down the iter directly instead of calling
iov_iter_get_pages_alloc.

Instead of having to allocate a page array, use CEPH_MSG_DATA_ITER and
pass it the iov_iter directly to clone.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-and-tested-by: Luís Henriques <lhenriques@suse.de>
Reviewed-by: Milind Changire <mchangir@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index f45ebe9..611443d 100644 (file)
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -246,7 +246,6 @@ static void finish_netfs_read(struct ceph_osd_request *req)
        struct ceph_osd_data *osd_data = osd_req_op_extent_osd_data(req, 0);
        struct netfs_io_subrequest *subreq = req->r_priv;
        struct ceph_osd_req_op *op = &req->r_ops[0];
-       int num_pages;
        int err = req->r_result;
        bool sparse = (op->op == CEPH_OSD_OP_SPARSE_READ);
 
@@ -268,9 +267,6 @@ static void finish_netfs_read(struct ceph_osd_request *req)
                __set_bit(NETFS_SREQ_CLEAR_TAIL, &subreq->flags);
 
        netfs_subreq_terminated(subreq, err, false);
-
-       num_pages = calc_pages_for(osd_data->alignment, osd_data->length);
-       ceph_put_page_vector(osd_data->pages, num_pages, false);
        iput(req->r_inode);
 }
 
@@ -338,8 +334,6 @@ static void ceph_netfs_issue_read(struct netfs_io_subrequest *subreq)
        struct ceph_osd_request *req = NULL;
        struct ceph_vino vino = ceph_vino(inode);
        struct iov_iter iter;
-       struct page **pages;
-       size_t page_off;
        int err = 0;
        u64 len = subreq->len;
        bool sparse = ceph_test_mount_opt(fsc, SPARSEREAD);
@@ -370,18 +364,7 @@ static void ceph_netfs_issue_read(struct netfs_io_subrequest *subreq)
 
        dout("%s: pos=%llu orig_len=%zu len=%llu\n", __func__, subreq->start, subreq->len, len);
        iov_iter_xarray(&iter, ITER_DEST, &rreq->mapping->i_pages, subreq->start, len);
-       err = iov_iter_get_pages_alloc2(&iter, &pages, len, &page_off);
-       if (err < 0) {
-               dout("%s: iov_ter_get_pages_alloc returned %d\n", __func__, err);
-               goto out;
-       }
-
-       /* should always give us a page-aligned read */
-       WARN_ON_ONCE(page_off);
-       len = err;
-       err = 0;
-
-       osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0, false, false);
+       osd_req_op_extent_osd_iter(req, 0, &iter);
        req->r_callback = finish_netfs_read;
        req->r_priv = subreq;
        req->r_inode = inode;