aboutsummaryrefslogtreecommitdiff
path: root/fs/ceph/pagelist.h
diff options
context:
space:
mode:
authorSage Weil <sage@newdream.net>2009-12-23 12:12:31 -0800
committerSage Weil <sage@newdream.net>2009-12-23 12:12:31 -0800
commit58bb3b374b07a2a43315213f00a48a5ffd6d0915 (patch)
tree04599b1f6c5f8bf501a1070b5ab7269a9a97fece /fs/ceph/pagelist.h
parent04a419f908b5291ff7e8ffd7aa351fa0ac0c08af (diff)
ceph: support ceph_pagelist for message payload
The ceph_pagelist is a simple list of whole pages, strung together via their lru list_head. It facilitates encoding to a "buffer" of unknown size. Allow its use in place of the ceph_msg page vector. This will be used to fix the huge buffer preallocation woes of MDS reconnection. Signed-off-by: Sage Weil <sage@newdream.net>
Diffstat (limited to 'fs/ceph/pagelist.h')
-rw-r--r--fs/ceph/pagelist.h54
1 files changed, 54 insertions, 0 deletions
diff --git a/fs/ceph/pagelist.h b/fs/ceph/pagelist.h
new file mode 100644
index 00000000000..e8a4187e108
--- /dev/null
+++ b/fs/ceph/pagelist.h
@@ -0,0 +1,54 @@
+#ifndef __FS_CEPH_PAGELIST_H
+#define __FS_CEPH_PAGELIST_H
+
+#include <linux/list.h>
+
+struct ceph_pagelist {
+ struct list_head head;
+ void *mapped_tail;
+ size_t length;
+ size_t room;
+};
+
+static inline void ceph_pagelist_init(struct ceph_pagelist *pl)
+{
+ INIT_LIST_HEAD(&pl->head);
+ pl->mapped_tail = NULL;
+ pl->length = 0;
+ pl->room = 0;
+}
+extern int ceph_pagelist_release(struct ceph_pagelist *pl);
+
+extern int ceph_pagelist_append(struct ceph_pagelist *pl, void *d, size_t l);
+
+static inline int ceph_pagelist_encode_64(struct ceph_pagelist *pl, u64 v)
+{
+ __le64 ev = cpu_to_le64(v);
+ return ceph_pagelist_append(pl, &ev, sizeof(ev));
+}
+static inline int ceph_pagelist_encode_32(struct ceph_pagelist *pl, u32 v)
+{
+ __le32 ev = cpu_to_le32(v);
+ return ceph_pagelist_append(pl, &ev, sizeof(ev));
+}
+static inline int ceph_pagelist_encode_16(struct ceph_pagelist *pl, u16 v)
+{
+ __le16 ev = cpu_to_le16(v);
+ return ceph_pagelist_append(pl, &ev, sizeof(ev));
+}
+static inline int ceph_pagelist_encode_8(struct ceph_pagelist *pl, u8 v)
+{
+ return ceph_pagelist_append(pl, &v, 1);
+}
+static inline int ceph_pagelist_encode_string(struct ceph_pagelist *pl,
+ char *s, size_t len)
+{
+ int ret = ceph_pagelist_encode_32(pl, len);
+ if (ret)
+ return ret;
+ if (len)
+ return ceph_pagelist_append(pl, s, len);
+ return 0;
+}
+
+#endif