rbd: move OSD request allocation into object request state machines

Following submission, move initial OSD request allocation into object
request state machines.  Everything that has to do with OSD requests is
now handled inside the state machine, all __rbd_img_fill_request() has
left is initialization.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Dongsheng Yang <dongsheng.yang@easystack.cn>

1 files changed, 96 insertions, 118 deletions

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index dd7dcf12426f..8bc78ae0ab5e 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -1408,15 +1408,13 @@ static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request,
 	rbd_obj_request_put(obj_request);
 }
 
-static void rbd_obj_request_submit(struct rbd_obj_request *obj_request)
+static void rbd_osd_submit(struct ceph_osd_request *osd_req)
 {
-	struct ceph_osd_request *osd_req =
-	    list_last_entry(&obj_request->osd_reqs, struct ceph_osd_request,
-			    r_private_item);
+	struct rbd_obj_request *obj_req = osd_req->r_priv;
 
-	dout("%s %p object_no %016llx %llu~%llu osd_req %p\n", __func__,
-	     obj_request, obj_request->ex.oe_objno, obj_request->ex.oe_off,
-	     obj_request->ex.oe_len, osd_req);
+	dout("%s osd_req %p for obj_req %p objno %llu %llu~%llu\n",
+	     __func__, osd_req, obj_req, obj_req->ex.oe_objno,
+	     obj_req->ex.oe_off, obj_req->ex.oe_len);
 	ceph_osdc_start_request(osd_req->r_osdc, osd_req, false);
 }
 
@@ -1823,17 +1821,6 @@ static void rbd_osd_setup_data(struct ceph_osd_request *osd_req, int which)
 
 static int rbd_obj_setup_read(struct rbd_obj_request *obj_req)
 {
-	struct ceph_osd_request *osd_req;
-
-	osd_req = __rbd_obj_add_osd_request(obj_req, NULL, 1);
-	if (IS_ERR(osd_req))
-		return PTR_ERR(osd_req);
-
-	osd_req_op_extent_init(osd_req, 0, CEPH_OSD_OP_READ,
-			       obj_req->ex.oe_off, obj_req->ex.oe_len, 0, 0);
-	rbd_osd_setup_data(osd_req, 0);
-
-	rbd_osd_format_read(osd_req);
 	obj_req->read_state = RBD_OBJ_READ_START;
 	return 0;
 }
@@ -1876,11 +1863,6 @@ static int rbd_osd_setup_copyup(struct ceph_osd_request *osd_req, int which,
 	return 0;
 }
 
-static int count_write_ops(struct rbd_obj_request *obj_req)
-{
-	return 2; /* setallochint + write/writefull */
-}
-
 static void __rbd_osd_setup_write_ops(struct ceph_osd_request *osd_req,
 				      int which)
 {
@@ -1900,14 +1882,10 @@ static void __rbd_osd_setup_write_ops(struct ceph_osd_request *osd_req,
 	osd_req_op_extent_init(osd_req, which, opcode,
 			       obj_req->ex.oe_off, obj_req->ex.oe_len, 0, 0);
 	rbd_osd_setup_data(osd_req, which);
-
-	rbd_osd_format_write(osd_req);
 }
 
 static int rbd_obj_setup_write(struct rbd_obj_request *obj_req)
 {
-	struct ceph_osd_request *osd_req;
-	unsigned int num_osd_ops, which = 0;
 	int ret;
 
 	/* reverse map the entire object onto the parent */
@@ -1918,22 +1896,7 @@ static int rbd_obj_setup_write(struct rbd_obj_request *obj_req)
 	if (rbd_obj_copyup_enabled(obj_req))
 		obj_req->flags |= RBD_OBJ_FLAG_COPYUP_ENABLED;
 
-	num_osd_ops = count_write_ops(obj_req);
-	if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED)
-		num_osd_ops++; /* stat */
-
-	osd_req = rbd_obj_add_osd_request(obj_req, num_osd_ops);
-	if (IS_ERR(osd_req))
-		return PTR_ERR(osd_req);
-
-	if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED) {
-		ret = rbd_osd_setup_stat(osd_req, which++);
-		if (ret)
-			return ret;
-	}
-
 	obj_req->write_state = RBD_OBJ_WRITE_START;
-	__rbd_osd_setup_write_ops(osd_req, which);
 	return 0;
 }
 
@@ -1962,7 +1925,6 @@ static void __rbd_osd_setup_discard_ops(struct ceph_osd_request *osd_req,
 static int rbd_obj_setup_discard(struct rbd_obj_request *obj_req)
 {
 	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
-	struct ceph_osd_request *osd_req;
 	u64 off, next_off;
 	int ret;
 
@@ -1997,29 +1959,10 @@ static int rbd_obj_setup_discard(struct rbd_obj_request *obj_req)
 	if (rbd_obj_is_entire(obj_req) && !obj_req->num_img_extents)
 		obj_req->flags |= RBD_OBJ_FLAG_DELETION;
 
-	osd_req = rbd_obj_add_osd_request(obj_req, 1);
-	if (IS_ERR(osd_req))
-		return PTR_ERR(osd_req);
-
 	obj_req->write_state = RBD_OBJ_WRITE_START;
-	__rbd_osd_setup_discard_ops(osd_req, 0);
-	rbd_osd_format_write(osd_req);
 	return 0;
 }
 
-static int count_zeroout_ops(struct rbd_obj_request *obj_req)
-{
-	int num_osd_ops;
-
-	if (rbd_obj_is_entire(obj_req) && obj_req->num_img_extents &&
-	    !rbd_obj_copyup_enabled(obj_req))
-		num_osd_ops = 2; /* create + truncate */
-	else
-		num_osd_ops = 1; /* delete/truncate/zero */
-
-	return num_osd_ops;
-}
-
 static void __rbd_osd_setup_zeroout_ops(struct ceph_osd_request *osd_req,
 					int which)
 {
@@ -2046,14 +1989,10 @@ static void __rbd_osd_setup_zeroout_ops(struct ceph_osd_request *osd_req,
 		osd_req_op_extent_init(osd_req, which, opcode,
 				       obj_req->ex.oe_off, obj_req->ex.oe_len,
 				       0, 0);
-
-	rbd_osd_format_write(osd_req);
 }
 
 static int rbd_obj_setup_zeroout(struct rbd_obj_request *obj_req)
 {
-	struct ceph_osd_request *osd_req;
-	unsigned int num_osd_ops, which = 0;
 	int ret;
 
 	/* reverse map the entire object onto the parent */
@@ -2068,34 +2007,56 @@ static int rbd_obj_setup_zeroout(struct rbd_obj_request *obj_req)
 			obj_req->flags |= RBD_OBJ_FLAG_DELETION;
 	}
 
-	num_osd_ops = count_zeroout_ops(obj_req);
-	if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED)
-		num_osd_ops++; /* stat */
+	obj_req->write_state = RBD_OBJ_WRITE_START;
+	return 0;
+}
 
-	osd_req = rbd_obj_add_osd_request(obj_req, num_osd_ops);
-	if (IS_ERR(osd_req))
-		return PTR_ERR(osd_req);
+static int count_write_ops(struct rbd_obj_request *obj_req)
+{
+	switch (obj_req->img_request->op_type) {
+	case OBJ_OP_WRITE:
+		return 2; /* setallochint + write/writefull */
+	case OBJ_OP_DISCARD:
+		return 1; /* delete/truncate/zero */
+	case OBJ_OP_ZEROOUT:
+		if (rbd_obj_is_entire(obj_req) && obj_req->num_img_extents &&
+		    !(obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED))
+			return 2; /* create + truncate */
 
-	if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED) {
-		ret = rbd_osd_setup_stat(osd_req, which++);
-		if (ret)
-			return ret;
+		return 1; /* delete/truncate/zero */
+	default:
+		BUG();
 	}
+}
 
-	obj_req->write_state = RBD_OBJ_WRITE_START;
-	__rbd_osd_setup_zeroout_ops(osd_req, which);
-	return 0;
+static void rbd_osd_setup_write_ops(struct ceph_osd_request *osd_req,
+				    int which)
+{
+	struct rbd_obj_request *obj_req = osd_req->r_priv;
+
+	switch (obj_req->img_request->op_type) {
+	case OBJ_OP_WRITE:
+		__rbd_osd_setup_write_ops(osd_req, which);
+		break;
+	case OBJ_OP_DISCARD:
+		__rbd_osd_setup_discard_ops(osd_req, which);
+		break;
+	case OBJ_OP_ZEROOUT:
+		__rbd_osd_setup_zeroout_ops(osd_req, which);
+		break;
+	default:
+		BUG();
+	}
 }
 
 /*
- * For each object request in @img_req, allocate an OSD request, add
- * individual OSD ops and prepare them for submission.  The number of
- * OSD ops depends on op_type and the overlap point (if any).
+ * Prune the list of object requests (adjust offset and/or length, drop
+ * redundant requests).  Prepare object request state machines and image
+ * request state machine for execution.
  */
 static int __rbd_img_fill_request(struct rbd_img_request *img_req)
 {
 	struct rbd_obj_request *obj_req, *next_obj_req;
-	struct ceph_osd_request *osd_req;
 	int ret;
 
 	for_each_obj_request_safe(img_req, obj_req, next_obj_req) {
@@ -2121,13 +2082,6 @@ static int __rbd_img_fill_request(struct rbd_img_request *img_req)
 			rbd_img_obj_request_del(img_req, obj_req);
 			continue;
 		}
-
-		osd_req = list_last_entry(&obj_req->osd_reqs,
-					  struct ceph_osd_request,
-					  r_private_item);
-		ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO);
-		if (ret)
-			return ret;
 	}
 
 	img_req->state = RBD_IMG_START;
@@ -2436,7 +2390,23 @@ static void rbd_img_schedule(struct rbd_img_request *img_req, int result)
 
 static int rbd_obj_read_object(struct rbd_obj_request *obj_req)
 {
-	rbd_obj_request_submit(obj_req);
+	struct ceph_osd_request *osd_req;
+	int ret;
+
+	osd_req = __rbd_obj_add_osd_request(obj_req, NULL, 1);
+	if (IS_ERR(osd_req))
+		return PTR_ERR(osd_req);
+
+	osd_req_op_extent_init(osd_req, 0, CEPH_OSD_OP_READ,
+			       obj_req->ex.oe_off, obj_req->ex.oe_len, 0, 0);
+	rbd_osd_setup_data(osd_req, 0);
+	rbd_osd_format_read(osd_req);
+
+	ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO);
+	if (ret)
+		return ret;
+
+	rbd_osd_submit(osd_req);
 	return 0;
 }
 
@@ -2549,7 +2519,32 @@ static bool rbd_obj_advance_read(struct rbd_obj_request *obj_req, int *result)
 
 static int rbd_obj_write_object(struct rbd_obj_request *obj_req)
 {
-	rbd_obj_request_submit(obj_req);
+	struct ceph_osd_request *osd_req;
+	int num_ops = count_write_ops(obj_req);
+	int which = 0;
+	int ret;
+
+	if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED)
+		num_ops++; /* stat */
+
+	osd_req = rbd_obj_add_osd_request(obj_req, num_ops);
+	if (IS_ERR(osd_req))
+		return PTR_ERR(osd_req);
+
+	if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED) {
+		ret = rbd_osd_setup_stat(osd_req, which++);
+		if (ret)
+			return ret;
+	}
+
+	rbd_osd_setup_write_ops(osd_req, which);
+	rbd_osd_format_write(osd_req);
+
+	ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO);
+	if (ret)
+		return ret;
+
+	rbd_osd_submit(osd_req);
 	return 0;
 }
 
@@ -2596,32 +2591,23 @@ static int rbd_obj_issue_copyup_empty_snapc(struct rbd_obj_request *obj_req,
 	if (ret)
 		return ret;
 
-	rbd_obj_request_submit(obj_req);
+	rbd_osd_submit(osd_req);
 	return 0;
 }
 
 static int rbd_obj_issue_copyup_ops(struct rbd_obj_request *obj_req, u32 bytes)
 {
-	struct rbd_img_request *img_req = obj_req->img_request;
 	struct ceph_osd_request *osd_req;
-	unsigned int num_osd_ops = (bytes != MODS_ONLY);
-	unsigned int which = 0;
+	int num_ops = count_write_ops(obj_req);
+	int which = 0;
 	int ret;
 
 	dout("%s obj_req %p bytes %u\n", __func__, obj_req, bytes);
 
-	switch (img_req->op_type) {
-	case OBJ_OP_WRITE:
-		num_osd_ops += count_write_ops(obj_req);
-		break;
-	case OBJ_OP_ZEROOUT:
-		num_osd_ops += count_zeroout_ops(obj_req);
-		break;
-	default:
-		BUG();
-	}
+	if (bytes != MODS_ONLY)
+		num_ops++; /* copyup */
 
-	osd_req = rbd_obj_add_osd_request(obj_req, num_osd_ops);
+	osd_req = rbd_obj_add_osd_request(obj_req, num_ops);
 	if (IS_ERR(osd_req))
 		return PTR_ERR(osd_req);
 
@@ -2631,22 +2617,14 @@ static int rbd_obj_issue_copyup_ops(struct rbd_obj_request *obj_req, u32 bytes)
 			return ret;
 	}
 
-	switch (img_req->op_type) {
-	case OBJ_OP_WRITE:
-		__rbd_osd_setup_write_ops(osd_req, which);
-		break;
-	case OBJ_OP_ZEROOUT:
-		__rbd_osd_setup_zeroout_ops(osd_req, which);
-		break;
-	default:
-		BUG();
-	}
+	rbd_osd_setup_write_ops(osd_req, which);
+	rbd_osd_format_write(osd_req);
 
 	ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO);
 	if (ret)
 		return ret;
 
-	rbd_obj_request_submit(obj_req);
+	rbd_osd_submit(osd_req);
 	return 0;
 }