1 files changed, 75 insertions, 0 deletions

diff --git a/include/linux/ceph/pagelist.h b/include/linux/ceph/pagelist.h
new file mode 100644
index 000000000000..9660d6b0a35d
--- /dev/null
+++ b/include/linux/ceph/pagelist.h
@@ -0,0 +1,75 @@
+#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;
+        struct list_head free_list;
+        size_t num_pages_free;
+};
+
+struct ceph_pagelist_cursor {
+        struct ceph_pagelist *pl;   /* pagelist, for error checking */
+        struct list_head *page_lru; /* page in list */
+        size_t room;                /* room remaining to reset to */
+};
+
+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;
+        INIT_LIST_HEAD(&pl->free_list);
+        pl->num_pages_free = 0;
+}
+
+extern int ceph_pagelist_release(struct ceph_pagelist *pl);
+
+extern int ceph_pagelist_append(struct ceph_pagelist *pl, const void *d, size_t l);
+
+extern int ceph_pagelist_reserve(struct ceph_pagelist *pl, size_t space);
+
+extern int ceph_pagelist_free_reserve(struct ceph_pagelist *pl);
+
+extern void ceph_pagelist_set_cursor(struct ceph_pagelist *pl,
+                                     struct ceph_pagelist_cursor *c);
+
+extern int ceph_pagelist_truncate(struct ceph_pagelist *pl,
+                                  struct ceph_pagelist_cursor *c);
+
+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