aboutsummaryrefslogtreecommitdiff
path: root/drivers/block/drbd/drbd_state.h
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/block/drbd/drbd_state.h')
-rw-r--r--drivers/block/drbd/drbd_state.h161
1 files changed, 161 insertions, 0 deletions
diff --git a/drivers/block/drbd/drbd_state.h b/drivers/block/drbd/drbd_state.h
new file mode 100644
index 00000000000..a3c361bbc4b
--- /dev/null
+++ b/drivers/block/drbd/drbd_state.h
@@ -0,0 +1,161 @@
+#ifndef DRBD_STATE_H
+#define DRBD_STATE_H
+
+struct drbd_conf;
+struct drbd_tconn;
+
+/**
+ * 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 = drbd_read_state(D); __ns.T = (S); __ns; })
+#define _NS2(D, T1, S1, T2, S2) \
+ D, ({ union drbd_state __ns; __ns = drbd_read_state(D); __ns.T1 = (S1); \
+ __ns.T2 = (S2); __ns; })
+#define _NS3(D, T1, S1, T2, S2, T3, S3) \
+ D, ({ union drbd_state __ns; __ns = drbd_read_state(D); __ns.T1 = (S1); \
+ __ns.T2 = (S2); __ns.T3 = (S3); __ns; })
+
+enum chg_state_flags {
+ CS_HARD = 1 << 0,
+ CS_VERBOSE = 1 << 1,
+ CS_WAIT_COMPLETE = 1 << 2,
+ CS_SERIALIZE = 1 << 3,
+ CS_ORDERED = CS_WAIT_COMPLETE + CS_SERIALIZE,
+ CS_LOCAL_ONLY = 1 << 4, /* Do not consider a device pair wide state change */
+ CS_DC_ROLE = 1 << 5, /* DC = display as connection state change */
+ CS_DC_PEER = 1 << 6,
+ CS_DC_CONN = 1 << 7,
+ CS_DC_DISK = 1 << 8,
+ CS_DC_PDSK = 1 << 9,
+ CS_DC_SUSP = 1 << 10,
+ CS_DC_MASK = CS_DC_ROLE + CS_DC_PEER + CS_DC_CONN + CS_DC_DISK + CS_DC_PDSK,
+ CS_IGN_OUTD_FAIL = 1 << 11,
+};
+
+/* drbd_dev_state and drbd_state are different types. This is to stress the
+ small difference. There is no suspended flag (.susp), and no suspended
+ while fence handler runs flas (susp_fen). */
+union drbd_dev_state {
+ struct {
+#if defined(__LITTLE_ENDIAN_BITFIELD)
+ unsigned role:2 ; /* 3/4 primary/secondary/unknown */
+ unsigned peer:2 ; /* 3/4 primary/secondary/unknown */
+ unsigned conn:5 ; /* 17/32 cstates */
+ unsigned disk:4 ; /* 8/16 from D_DISKLESS to D_UP_TO_DATE */
+ unsigned pdsk:4 ; /* 8/16 from D_DISKLESS to D_UP_TO_DATE */
+ unsigned _unused:1 ;
+ unsigned aftr_isp:1 ; /* isp .. imposed sync pause */
+ unsigned peer_isp:1 ;
+ unsigned user_isp:1 ;
+ unsigned _pad:11; /* 0 unused */
+#elif defined(__BIG_ENDIAN_BITFIELD)
+ unsigned _pad:11;
+ unsigned user_isp:1 ;
+ unsigned peer_isp:1 ;
+ unsigned aftr_isp:1 ; /* isp .. imposed sync pause */
+ unsigned _unused:1 ;
+ unsigned pdsk:4 ; /* 8/16 from D_DISKLESS to D_UP_TO_DATE */
+ unsigned disk:4 ; /* 8/16 from D_DISKLESS to D_UP_TO_DATE */
+ unsigned conn:5 ; /* 17/32 cstates */
+ unsigned peer:2 ; /* 3/4 primary/secondary/unknown */
+ unsigned role:2 ; /* 3/4 primary/secondary/unknown */
+#else
+# error "this endianess is not supported"
+#endif
+ };
+ unsigned int i;
+};
+
+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);
+
+enum drbd_state_rv
+_conn_request_state(struct drbd_tconn *tconn, union drbd_state mask, union drbd_state val,
+ enum chg_state_flags flags);
+
+enum drbd_state_rv
+conn_request_state(struct drbd_tconn *tconn, union drbd_state mask, union drbd_state val,
+ enum chg_state_flags flags);
+
+extern void drbd_resume_al(struct drbd_conf *mdev);
+extern bool conn_all_vols_unconf(struct drbd_tconn *tconn);
+
+/**
+ * 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);
+}
+
+enum drbd_role conn_highest_role(struct drbd_tconn *tconn);
+enum drbd_role conn_highest_peer(struct drbd_tconn *tconn);
+enum drbd_disk_state conn_highest_disk(struct drbd_tconn *tconn);
+enum drbd_disk_state conn_lowest_disk(struct drbd_tconn *tconn);
+enum drbd_disk_state conn_highest_pdsk(struct drbd_tconn *tconn);
+enum drbd_conns conn_lowest_conn(struct drbd_tconn *tconn);
+
+#endif