[RFC PATCH 1/3] libceph: add non-blocking version of ceph_osdc_copy_from()

[Luis Henriques <lhenriques@xxxxxxxx>]

A non-blocking version of ceph_osdc_copy_from will allow for callers to
send 'copy-from' requests in bulk and wait for all of them to complete in
the end.

Signed-off-by: Luis Henriques <lhenriques@xxxxxxxx>
---
 include/linux/ceph/osd_client.h | 12 ++++++++
 net/ceph/osd_client.c           | 54 +++++++++++++++++++++++++--------
 2 files changed, 53 insertions(+), 13 deletions(-)

diff --git a/include/linux/ceph/osd_client.h b/include/linux/ceph/osd_client.h
index 5a62dbd3f4c2..7916a178d137 100644
--- a/include/linux/ceph/osd_client.h
+++ b/include/linux/ceph/osd_client.h
@@ -537,6 +537,18 @@ int ceph_osdc_copy_from(struct ceph_osd_client *osdc,
 			u32 truncate_seq, u64 truncate_size,
 			u8 copy_from_flags);
 
+struct ceph_osd_request *ceph_osdc_copy_from_nowait(
+			struct ceph_osd_client *osdc,
+			u64 src_snapid, u64 src_version,
+			struct ceph_object_id *src_oid,
+			struct ceph_object_locator *src_oloc,
+			u32 src_fadvise_flags,
+			struct ceph_object_id *dst_oid,
+			struct ceph_object_locator *dst_oloc,
+			u32 dst_fadvise_flags,
+			u32 truncate_seq, u64 truncate_size,
+			u8 copy_from_flags);
+
 /* watch/notify */
 struct ceph_osd_linger_request *
 ceph_osdc_watch(struct ceph_osd_client *osdc,
diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index b68b376d8c2f..7f984532f37c 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -5346,23 +5346,24 @@ static int osd_req_op_copy_from_init(struct ceph_osd_request *req,
 	return 0;
 }
 
-int ceph_osdc_copy_from(struct ceph_osd_client *osdc,
-			u64 src_snapid, u64 src_version,
-			struct ceph_object_id *src_oid,
-			struct ceph_object_locator *src_oloc,
-			u32 src_fadvise_flags,
-			struct ceph_object_id *dst_oid,
-			struct ceph_object_locator *dst_oloc,
-			u32 dst_fadvise_flags,
-			u32 truncate_seq, u64 truncate_size,
-			u8 copy_from_flags)
+struct ceph_osd_request *ceph_osdc_copy_from_nowait(
+		struct ceph_osd_client *osdc,
+		u64 src_snapid, u64 src_version,
+		struct ceph_object_id *src_oid,
+		struct ceph_object_locator *src_oloc,
+		u32 src_fadvise_flags,
+		struct ceph_object_id *dst_oid,
+		struct ceph_object_locator *dst_oloc,
+		u32 dst_fadvise_flags,
+		u32 truncate_seq, u64 truncate_size,
+		u8 copy_from_flags)
 {
 	struct ceph_osd_request *req;
 	int ret;
 
 	req = ceph_osdc_alloc_request(osdc, NULL, 1, false, GFP_KERNEL);
 	if (!req)
-		return -ENOMEM;
+		return ERR_PTR(-ENOMEM);
 
 	req->r_flags = CEPH_OSD_FLAG_WRITE;
 
@@ -5381,11 +5382,38 @@ int ceph_osdc_copy_from(struct ceph_osd_client *osdc,
 		goto out;
 
 	ceph_osdc_start_request(osdc, req, false);
-	ret = ceph_osdc_wait_request(osdc, req);
+	return req;
 
 out:
 	ceph_osdc_put_request(req);
-	return ret;
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL(ceph_osdc_copy_from_nowait);
+
+int ceph_osdc_copy_from(struct ceph_osd_client *osdc,
+			u64 src_snapid, u64 src_version,
+			struct ceph_object_id *src_oid,
+			struct ceph_object_locator *src_oloc,
+			u32 src_fadvise_flags,
+			struct ceph_object_id *dst_oid,
+			struct ceph_object_locator *dst_oloc,
+			u32 dst_fadvise_flags,
+			u32 truncate_seq, u64 truncate_size,
+			u8 copy_from_flags)
+{
+	struct ceph_osd_request *req;
+
+	req = ceph_osdc_copy_from_nowait(osdc,
+			src_snapid, src_version,
+			src_oid, src_oloc,
+			src_fadvise_flags,
+			dst_oid, dst_oloc,
+			dst_fadvise_flags,
+			truncate_seq, truncate_size,
+			copy_from_flags);
+	if (IS_ERR(req))
+		return PTR_ERR(req);
+	return ceph_osdc_wait_request(osdc, req);
 }
 EXPORT_SYMBOL(ceph_osdc_copy_from);