[PATCH 0/2] libceph: simplify ceph_osdc_alloc_request()

[PATCH 0/2] libceph: simplify ceph_osdc_alloc_request()

[Alex Elder]

These two patches just move a couple of things that
ceph_osdc_alloc_request() does out and into the caller.
It simplifies the function slightly, and makes it possible
for some callers to not have to supply irrelevant arguments.

					-Alex

[PATCH 1/2] libceph: don't set flags in ceph_osdc_alloc_request()
[PATCH 2/2] libceph: don't set pages or bio in ceph_osdc_alloc_request()

[PATCH 1/2] libceph: don't set flags in ceph_osdc_alloc_request()

[Alex Elder]

The only thing ceph_osdc_alloc_request() really does with the
flags value it is passed is assign it to the newly-created
osd request structure.  Do that in the caller instead.

Both callers subsequently call ceph_osdc_build_request(), so have
that function (instead of ceph_osdc_alloc_request()) issue a warning
if a request comes through with neither the read nor write flags set.

Signed-off-by: Alex Elder <elder@inktank.com>
---
 drivers/block/rbd.c             |    3 ++-
 include/linux/ceph/osd_client.h |    1 -
 net/ceph/osd_client.c           |   11 ++++-------
 3 files changed, 6 insertions(+), 9 deletions(-)

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 2d10504..b6b1522 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -1150,13 +1150,14 @@ static int rbd_do_request(struct request *rq,
 		(unsigned long long) len, coll, coll_index);

 	osdc = &rbd_dev->rbd_client->client->osdc;
-	osd_req = ceph_osdc_alloc_request(osdc, flags, snapc, ops,
+	osd_req = ceph_osdc_alloc_request(osdc, snapc, ops,
 					false, GFP_NOIO, pages, bio);
 	if (!osd_req) {
 		ret = -ENOMEM;
 		goto done_pages;
 	}

+	osd_req->r_flags = flags;
 	osd_req->r_callback = rbd_cb;

 	rbd_req->rq = rq;
diff --git a/include/linux/ceph/osd_client.h
b/include/linux/ceph/osd_client.h
index fe3a6e8..6ddda5b 100644
--- a/include/linux/ceph/osd_client.h
+++ b/include/linux/ceph/osd_client.h
@@ -213,7 +213,6 @@ extern int ceph_calc_raw_layout(struct
ceph_file_layout *layout,
 			struct ceph_osd_req_op *op);

 extern struct ceph_osd_request *ceph_osdc_alloc_request(struct
ceph_osd_client *osdc,
-					       int flags,
 					       struct ceph_snap_context *snapc,
 					       struct ceph_osd_req_op *ops,
 					       bool use_mempool,
diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index baaec06..3e82e61 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -163,7 +163,6 @@ static int get_num_ops(struct ceph_osd_req_op *ops)
 }

 struct ceph_osd_request *ceph_osdc_alloc_request(struct ceph_osd_client
*osdc,
-					       int flags,
 					       struct ceph_snap_context *snapc,
 					       struct ceph_osd_req_op *ops,
 					       bool use_mempool,
@@ -200,10 +199,6 @@ struct ceph_osd_request
*ceph_osdc_alloc_request(struct ceph_osd_client *osdc,
 	INIT_LIST_HEAD(&req->r_req_lru_item);
 	INIT_LIST_HEAD(&req->r_osd_item);

-	req->r_flags = flags;
-
-	WARN_ON((flags & (CEPH_OSD_FLAG_READ|CEPH_OSD_FLAG_WRITE)) == 0);
-
 	/* create reply message */
 	if (use_mempool)
 		msg = ceph_msgpool_get(&osdc->msgpool_op_reply, 0);
@@ -339,6 +334,8 @@ void ceph_osdc_build_request(struct ceph_osd_request
*req,
 	u64 data_len = 0;
 	int i;

+	WARN_ON((flags & (CEPH_OSD_FLAG_READ|CEPH_OSD_FLAG_WRITE)) == 0);
+
 	head = msg->front.iov_base;
 	head->snapid = cpu_to_le64(snap_id);
 	op = (void *)(head + 1);
@@ -434,12 +431,12 @@ struct ceph_osd_request
*ceph_osdc_new_request(struct ceph_osd_client *osdc,
 	} else
 		ops[1].op = 0;

-	req = ceph_osdc_alloc_request(osdc, flags,
-					 snapc, ops,
+	req = ceph_osdc_alloc_request(osdc, snapc, ops,
 					 use_mempool,
 					 GFP_NOFS, NULL, NULL);
 	if (!req)
 		return ERR_PTR(-ENOMEM);
+	req->r_flags = flags;

 	/* calculate max write size */
 	r = calc_layout(vino, layout, off, plen, req, ops);
-- 
1.7.9.5

[PATCH 2/2] libceph: don't set pages or bio in ceph_osdc_alloc_request()

[Alex Elder]

Only one of the two callers of ceph_osdc_alloc_request() provides
page or bio data for its payload.  And essentially all that function
was doing with those arguments was assigning them to fields in the
osd request structure.

Simplify ceph_osdc_alloc_request() by having the caller take care of
making those assignments

Signed-off-by: Alex Elder <elder@inktank.com>
---
 drivers/block/rbd.c             |    8 ++++++--
 include/linux/ceph/osd_client.h |    4 +---
 net/ceph/osd_client.c           |   15 ++-------------
 3 files changed, 9 insertions(+), 18 deletions(-)

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index b6b1522..bdb099c 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -1150,14 +1150,18 @@ static int rbd_do_request(struct request *rq,
 		(unsigned long long) len, coll, coll_index);

 	osdc = &rbd_dev->rbd_client->client->osdc;
-	osd_req = ceph_osdc_alloc_request(osdc, snapc, ops,
-					false, GFP_NOIO, pages, bio);
+	osd_req = ceph_osdc_alloc_request(osdc, snapc, ops, false, GFP_NOIO);
 	if (!osd_req) {
 		ret = -ENOMEM;
 		goto done_pages;
 	}

 	osd_req->r_flags = flags;
+	osd_req->r_pages = pages;
+	if (bio) {
+		osd_req->r_bio = bio;
+		bio_get(osd_req->r_bio);
+	}
 	osd_req->r_callback = rbd_cb;

 	rbd_req->rq = rq;
diff --git a/include/linux/ceph/osd_client.h
b/include/linux/ceph/osd_client.h
index 6ddda5b..75f56d3 100644
--- a/include/linux/ceph/osd_client.h
+++ b/include/linux/ceph/osd_client.h
@@ -216,9 +216,7 @@ extern struct ceph_osd_request
*ceph_osdc_alloc_request(struct ceph_osd_client *
 					       struct ceph_snap_context *snapc,
 					       struct ceph_osd_req_op *ops,
 					       bool use_mempool,
-					       gfp_t gfp_flags,
-					       struct page **pages,
-					       struct bio *bio);
+					       gfp_t gfp_flags);

 extern void ceph_osdc_build_request(struct ceph_osd_request *req,
 				    u64 off, u64 len,
diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index 3e82e61..5ed9c92 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -166,9 +166,7 @@ struct ceph_osd_request
*ceph_osdc_alloc_request(struct ceph_osd_client *osdc,
 					       struct ceph_snap_context *snapc,
 					       struct ceph_osd_req_op *ops,
 					       bool use_mempool,
-					       gfp_t gfp_flags,
-					       struct page **pages,
-					       struct bio *bio)
+					       gfp_t gfp_flags)
 {
 	struct ceph_osd_request *req;
 	struct ceph_msg *msg;
@@ -229,13 +227,6 @@ struct ceph_osd_request
*ceph_osdc_alloc_request(struct ceph_osd_client *osdc,
 	memset(msg->front.iov_base, 0, msg->front.iov_len);

 	req->r_request = msg;
-	req->r_pages = pages;
-#ifdef CONFIG_BLOCK
-	if (bio) {
-		req->r_bio = bio;
-		bio_get(req->r_bio);
-	}
-#endif

 	return req;
 }
@@ -431,9 +422,7 @@ struct ceph_osd_request
*ceph_osdc_new_request(struct ceph_osd_client *osdc,
 	} else
 		ops[1].op = 0;

-	req = ceph_osdc_alloc_request(osdc, snapc, ops,
-					 use_mempool,
-					 GFP_NOFS, NULL, NULL);
+	req = ceph_osdc_alloc_request(osdc, snapc, ops, use_mempool, GFP_NOFS);
 	if (!req)
 		return ERR_PTR(-ENOMEM);
 	req->r_flags = flags;
-- 
1.7.9.5