diff options
Diffstat (limited to 'drivers/block/drbd/drbd_state.h')
| -rw-r--r-- | drivers/block/drbd/drbd_state.h | 161 |
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 000000000000..a3c361bbc4b6 --- /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 |