drbd: Moved the state functions into its own source file

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

1 files changed, 101 insertions, 0 deletions

diff --git a/drivers/block/drbd/drbd_state.h b/drivers/block/drbd/drbd_state.h
new file mode 100644
index 000000000000..3ec26e2c4c40
--- /dev/null
+++ b/drivers/block/drbd/drbd_state.h
@@ -0,0 +1,101 @@
+#ifndef DRBD_STATE_H
+#define DRBD_STATE_H
+
+struct drbd_conf;
+
+/**
+ * DOC: DRBD State macros
+ *
+ * These macros are used to express state changes in easily readable form.
+ *
+ * The NS macros expand to a mask and a value, that can be bit ored onto the
+ * current state as soon as the spinlock (req_lock) was taken.
+ *
+ * The _NS macros are used for state functions that get called with the
+ * spinlock. These macros expand directly to the new state value.
+ *
+ * Besides the basic forms NS() and _NS() additional _?NS[23] are defined
+ * to express state changes that affect more than one aspect of the state.
+ *
+ * E.g. NS2(conn, C_CONNECTED, peer, R_SECONDARY)
+ * Means that the network connection was established and that the peer
+ * is in secondary role.
+ */
+#define role_MASK R_MASK
+#define peer_MASK R_MASK
+#define disk_MASK D_MASK
+#define pdsk_MASK D_MASK
+#define conn_MASK C_MASK
+#define susp_MASK 1
+#define user_isp_MASK 1
+#define aftr_isp_MASK 1
+#define susp_nod_MASK 1
+#define susp_fen_MASK 1
+
+#define NS(T, S) \
+        ({ union drbd_state mask; mask.i = 0; mask.T = T##_MASK; mask; }), \
+        ({ union drbd_state val; val.i = 0; val.T = (S); val; })
+#define NS2(T1, S1, T2, S2) \
+        ({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \
+          mask.T2 = T2##_MASK; mask; }), \
+        ({ union drbd_state val; val.i = 0; val.T1 = (S1); \
+          val.T2 = (S2); val; })
+#define NS3(T1, S1, T2, S2, T3, S3) \
+        ({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \
+          mask.T2 = T2##_MASK; mask.T3 = T3##_MASK; mask; }), \
+        ({ union drbd_state val;  val.i = 0; val.T1 = (S1); \
+          val.T2 = (S2); val.T3 = (S3); val; })
+
+#define _NS(D, T, S) \
+        D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T = (S); __ns; })
+#define _NS2(D, T1, S1, T2, S2) \
+        D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T1 = (S1); \
+        __ns.T2 = (S2); __ns; })
+#define _NS3(D, T1, S1, T2, S2, T3, S3) \
+        D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T1 = (S1); \
+        __ns.T2 = (S2); __ns.T3 = (S3); __ns; })
+
+enum chg_state_flags {
+        CS_HARD = 1,
+        CS_VERBOSE = 2,
+        CS_WAIT_COMPLETE = 4,
+        CS_SERIALIZE    = 8,
+        CS_ORDERED      = CS_WAIT_COMPLETE + CS_SERIALIZE,
+};
+
+extern enum drbd_state_rv drbd_change_state(struct drbd_conf *mdev,
+                                            enum chg_state_flags f,
+                                            union drbd_state mask,
+                                            union drbd_state val);
+extern void drbd_force_state(struct drbd_conf *, union drbd_state,
+                        union drbd_state);
+extern enum drbd_state_rv _drbd_request_state(struct drbd_conf *,
+                                              union drbd_state,
+                                              union drbd_state,
+                                              enum chg_state_flags);
+extern enum drbd_state_rv __drbd_set_state(struct drbd_conf *, union drbd_state,
+                                           enum chg_state_flags,
+                                           struct completion *done);
+extern void print_st_err(struct drbd_conf *, union drbd_state,
+                        union drbd_state, int);
+
+extern void drbd_resume_al(struct drbd_conf *mdev);
+
+/**
+ * drbd_request_state() - Reqest a state change
+ * @mdev:       DRBD device.
+ * @mask:       mask of state bits to change.
+ * @val:        value of new state bits.
+ *
+ * This is the most graceful way of requesting a state change. It is verbose
+ * quite verbose in case the state change is not possible, and all those
+ * state changes are globally serialized.
+ */
+static inline int drbd_request_state(struct drbd_conf *mdev,
+                                     union drbd_state mask,
+                                     union drbd_state val)
+{
+        return _drbd_request_state(mdev, mask, val, CS_VERBOSE + CS_ORDERED);
+}
+
+#endif