ceph: use ceph_create_snap_context()

Now that we have a library routine to create snap contexts, use it.

This is part of:
    http://tracker.ceph.com/issues/4857

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>

2 files changed, 7 insertions, 37 deletions

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index d41f97690343..5c1c38dc0b51 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -672,35 +672,6 @@ static void rbd_client_release(struct kref *kref)
         kfree(rbdc);
 }
 
-/* Caller has to fill in snapc->seq and snapc->snaps[0..snap_count-1] */
-
-static struct ceph_snap_context *rbd_snap_context_create(u32 snap_count)
-{
-        struct ceph_snap_context *snapc;
-        size_t size;
-
-        size = sizeof (struct ceph_snap_context);
-        size += snap_count * sizeof (snapc->snaps[0]);
-        snapc = kzalloc(size, GFP_KERNEL);
-        if (!snapc)
-                return NULL;
-
-        atomic_set(&snapc->nref, 1);
-        snapc->num_snaps = snap_count;
-
-        return snapc;
-}
-
-static inline void rbd_snap_context_get(struct ceph_snap_context *snapc)
-{
-        (void)ceph_get_snap_context(snapc);
-}
-
-static inline void rbd_snap_context_put(struct ceph_snap_context *snapc)
-{
-        ceph_put_snap_context(snapc);
-}
-
 /*
  * Drop reference to ceph client node. If it's not referenced anymore, release
  * it.
@@ -820,7 +791,7 @@ static int rbd_header_from_disk(struct rbd_image_header *header,
 
         header->image_size = le64_to_cpu(ondisk->image_size);
 
-        header->snapc = rbd_snap_context_create(snap_count);
+        header->snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
         if (!header->snapc)
                 goto out_err;
         header->snapc->seq = le64_to_cpu(ondisk->snap_seq);
@@ -1753,7 +1724,7 @@ static struct rbd_img_request *rbd_img_request_create(
 
         if (write_request) {
                 down_read(&rbd_dev->header_rwsem);
-                rbd_snap_context_get(rbd_dev->header.snapc);
+                ceph_get_snap_context(rbd_dev->header.snapc);
                 up_read(&rbd_dev->header_rwsem);
         }
 
@@ -1805,7 +1776,7 @@ static void rbd_img_request_destroy(struct kref *kref)
         rbd_assert(img_request->obj_request_count == 0);
 
         if (img_request_write_test(img_request))
-                rbd_snap_context_put(img_request->snapc);
+                ceph_put_snap_context(img_request->snapc);
 
         if (img_request_child_test(img_request))
                 rbd_obj_request_put(img_request->obj_request);
@@ -3071,7 +3042,7 @@ static int rbd_dev_v1_refresh(struct rbd_device *rbd_dev, u64 *hver)
         kfree(rbd_dev->header.snap_sizes);
         kfree(rbd_dev->header.snap_names);
         /* osd requests may still refer to snapc */
-        rbd_snap_context_put(rbd_dev->header.snapc);
+        ceph_put_snap_context(rbd_dev->header.snapc);
 
         if (hver)
                 *hver = h.obj_version;
@@ -3914,7 +3885,7 @@ static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev, u64 *ver)
                 goto out;
         ret = 0;
 
-        snapc = rbd_snap_context_create(snap_count);
+        snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
         if (!snapc) {
                 ret = -ENOMEM;
                 goto out;
@@ -4590,7 +4561,7 @@ static void rbd_dev_unprobe(struct rbd_device *rbd_dev)
         /* Free dynamic fields from the header, then zero it out */
 
         header = &rbd_dev->header;
-        rbd_snap_context_put(header->snapc);
+        ceph_put_snap_context(header->snapc);
         kfree(header->snap_sizes);
         kfree(header->snap_names);
         kfree(header->object_prefix);
diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c
index cbb2f54a3019..f01645a27752 100644
--- a/fs/ceph/snap.c
+++ b/fs/ceph/snap.c
@@ -332,10 +332,9 @@ static int build_snap_context(struct ceph_snap_realm *realm)
         err = -ENOMEM;
         if (num > (SIZE_MAX - sizeof(*snapc)) / sizeof(u64))
                 goto fail;
-        snapc = kzalloc(sizeof(*snapc) + num*sizeof(u64), GFP_NOFS);
+        snapc = ceph_create_snap_context(num, GFP_NOFS);
         if (!snapc)
                 goto fail;
-        atomic_set(&snapc->nref, 1);
 
         /* build (reverse sorted) snap vector */
         num = 0;