1 files changed, 97 insertions, 0 deletions
diff --git a/src/include/krbd.h b/src/include/krbd.h
new file mode 100644
index 000000000..977d45fe2
--- /dev/null
+++ b/src/include/krbd.h
@@ -0,0 +1,97 @@
+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2014 Inktank Storage, Inc.
+ *
+ * This is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2.1, as published by the Free Software
+ * Foundation.  See file COPYING.
+ *
+ */
+
+#ifndef CEPH_KRBD_H
+#define CEPH_KRBD_H
+
+#include "rados/librados.h"
+
+/*
+ * Don't wait for udev add uevents in krbd_map() and udev remove
+ * uevents in krbd_unmap*().  Instead, make do with the respective
+ * kernel uevents and return as soon as they are received.
+ *
+ * systemd-udevd sends out udev uevents after it finishes processing
+ * the respective kernel uevents, which mostly boils down to executing
+ * all matching udev rules.  With this flag set, on return from
+ * krbd_map() systemd-udevd may still be poking at the device: it
+ * may still be open with tools such as blkid and various ioctls to
+ * be run against it, none of the persistent symlinks to the device
+ * node may be there, etc.  udev used to be responsible for creating
+ * the device node as well, but that has been handled by devtmpfs in
+ * the kernel for many years now, so the device node (as returned
+ * through @pdevnode) is guaranteed to be there.
+ *
+ * If set, krbd_map() and krbd_unmap*() can be invoked from any
+ * network namespace that is owned by the initial user namespace
+ * (which is a formality because things like loading kernel modules
+ * and creating block devices are not namespaced and require global
+ * privileges, i.e. capabilities in the initial user namespace).
+ * Otherwise, krbd_map() and krbd_unmap*() must be invoked from
+ * the initial network namespace.
+ *
+ * If set, krbd_unmap*() doesn't attempt to settle the udev queue
+ * before retrying unmap for the last time.  Some EBUSY errors due
+ * to systemd-udevd poking at the device at the time krbd_unmap*()
+ * is invoked that are otherwise covered by the retry logic may be
+ * returned.
+ */
+#define KRBD_CTX_F_NOUDEV       (1U << 0)
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct krbd_ctx;
+
+int krbd_create_from_context(rados_config_t cct, uint32_t flags,
+                             struct krbd_ctx **pctx);
+void krbd_destroy(struct krbd_ctx *ctx);
+
+int krbd_map(struct krbd_ctx *ctx,
+             const char *pool_name,
+             const char *nspace_name,
+             const char *image_name,
+             const char *snap_name,
+             const char *options,
+             char **pdevnode);
+int krbd_is_mapped(struct krbd_ctx *ctx,
+                   const char *pool_name,
+                   const char *nspace_name,
+                   const char *image_name,
+                   const char *snap_name,
+                   char **pdevnode);
+
+int krbd_unmap(struct krbd_ctx *ctx, const char *devnode,
+               const char *options);
+int krbd_unmap_by_spec(struct krbd_ctx *ctx,
+                       const char *pool_name,
+                       const char *nspace_name,
+                       const char *image_name,
+                       const char *snap_name,
+                       const char *options);
+
+#ifdef __cplusplus
+}
+#endif
+
+#ifdef __cplusplus
+
+namespace ceph {
+  class Formatter;
+}
+
+int krbd_showmapped(struct krbd_ctx *ctx, ceph::Formatter *f);
+
+#endif /* __cplusplus */
+
+#endif /* CEPH_KRBD_H */