libceph: rados pool namespace support

Add pool namesapce pointer to struct ceph_file_layout and struct
ceph_object_locator. Pool namespace is used by when mapping object
to PG, it's also used when composing OSD request.

The namespace pointer in struct ceph_file_layout is RCU protected.
So libceph can read namespace without taking lock.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
[idryomov@gmail.com: ceph_oloc_destroy(), misc minor changes]
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

2 files changed, 7 insertions, 5 deletions

diff --git a/include/linux/ceph/ceph_fs.h b/include/linux/ceph/ceph_fs.h
index e5a5fb9ca3f5..08b8fd72261e 100644
--- a/include/linux/ceph/ceph_fs.h
+++ b/include/linux/ceph/ceph_fs.h
@@ -53,6 +53,7 @@ struct ceph_file_layout_legacy {
         __le32 fl_pg_pool;      /* namespace, crush ruleset, rep level */
 } __attribute__ ((packed));
 
+struct ceph_string;
 /*
  * ceph_file_layout - describe data layout for a file/inode
  */
@@ -62,6 +63,7 @@ struct ceph_file_layout {
         u32 stripe_count;  /* over this many objects */
         u32 object_size;   /* until objects are this big */
         s64 pool_id;        /* rados pool id */
+        struct ceph_string __rcu *pool_ns; /* rados pool namespace */
 };
 
 extern int ceph_file_layout_is_valid(const struct ceph_file_layout *layout);
diff --git a/include/linux/ceph/osdmap.h b/include/linux/ceph/osdmap.h
index 21d7f048959f..9a9041784dcf 100644
--- a/include/linux/ceph/osdmap.h
+++ b/include/linux/ceph/osdmap.h
@@ -63,11 +63,13 @@ static inline bool ceph_can_shift_osds(struct ceph_pg_pool_info *pool)
 
 struct ceph_object_locator {
         s64 pool;
+        struct ceph_string *pool_ns;
 };
 
 static inline void ceph_oloc_init(struct ceph_object_locator *oloc)
 {
         oloc->pool = -1;
+        oloc->pool_ns = NULL;
 }
 
 static inline bool ceph_oloc_empty(const struct ceph_object_locator *oloc)
@@ -75,11 +77,9 @@ static inline bool ceph_oloc_empty(const struct ceph_object_locator *oloc)
         return oloc->pool == -1;
 }
 
-static inline void ceph_oloc_copy(struct ceph_object_locator *dest,
-                                  const struct ceph_object_locator *src)
-{
-        dest->pool = src->pool;
-}
+void ceph_oloc_copy(struct ceph_object_locator *dest,
+                    const struct ceph_object_locator *src);
+void ceph_oloc_destroy(struct ceph_object_locator *oloc);
 
 /*
  * Maximum supported by kernel client object name length