libceph: add ceph_osdc_call() single-page helper

Add a convenience function to osd_client to send Ceph OSD
'class' ops. The interface assumes that the request and
reply data each consist of single pages.

Signed-off-by: Douglas Fuller <dfuller@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Alex Elder <elder@linaro.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/include/linux/ceph/osd_client.h b/include/linux/ceph/osd_client.h
index 19821a191732..96337b15a60d 100644
--- a/include/linux/ceph/osd_client.h
+++ b/include/linux/ceph/osd_client.h
@@ -397,6 +397,14 @@ extern void ceph_osdc_sync(struct ceph_osd_client *osdc);
 extern void ceph_osdc_flush_notifies(struct ceph_osd_client *osdc);
 void ceph_osdc_maybe_request_map(struct ceph_osd_client *osdc);
 
+int ceph_osdc_call(struct ceph_osd_client *osdc,
+                   struct ceph_object_id *oid,
+                   struct ceph_object_locator *oloc,
+                   const char *class, const char *method,
+                   unsigned int flags,
+                   struct page *req_page, size_t req_len,
+                   struct page *resp_page, size_t *resp_len);
+
 extern int ceph_osdc_readpages(struct ceph_osd_client *osdc,
                                struct ceph_vino vino,
                                struct ceph_file_layout *layout,