libceph: create source file "net/ceph/snapshot.c"

This creates a new source file "net/ceph/snapshot.c" to contain
utility routines related to ceph snapshot contexts.  The main
motivation was to define ceph_create_snap_context() as a common way
to create these structures, but I've moved the definitions of
ceph_get_snap_context() and ceph_put_snap_context() there too.
(The benefit of inlining those is very small, and I'd rather
keep this collection of functions together.)

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

1 files changed, 5 insertions, 25 deletions

diff --git a/include/linux/ceph/libceph.h b/include/linux/ceph/libceph.h
index 5493d7b86423..2e3024881a5e 100644
--- a/include/linux/ceph/libceph.h
+++ b/include/linux/ceph/libceph.h
@@ -157,31 +157,11 @@ struct ceph_snap_context {
         u64 snaps[];
 };
 
-static inline struct ceph_snap_context *
-ceph_get_snap_context(struct ceph_snap_context *sc)
-{
-        /*
-        printk("get_snap_context %p %d -> %d\n", sc, atomic_read(&sc->nref),
-               atomic_read(&sc->nref)+1);
-        */
-        if (sc)
-                atomic_inc(&sc->nref);
-        return sc;
-}
-
-static inline void ceph_put_snap_context(struct ceph_snap_context *sc)
-{
-        if (!sc)
-                return;
-        /*
-        printk("put_snap_context %p %d -> %d\n", sc, atomic_read(&sc->nref),
-               atomic_read(&sc->nref)-1);
-        */
-        if (atomic_dec_and_test(&sc->nref)) {
-                /*printk(" deleting snap_context %p\n", sc);*/
-                kfree(sc);
-        }
-}
+extern struct ceph_snap_context *ceph_create_snap_context(u32 snap_count,
+                                        gfp_t gfp_flags);
+extern struct ceph_snap_context *ceph_get_snap_context(
+                                        struct ceph_snap_context *sc);
+extern void ceph_put_snap_context(struct ceph_snap_context *sc);
 
 /*
  * calculate the number of pages a given length and offset map onto,