1/* SPDX-License-Identifier: GPL-2.0-only */
2#ifndef DRBD_STATE_H
3#define DRBD_STATE_H
4
5struct drbd_device;
6struct drbd_connection;
7
8/**
9 * DOC: DRBD State macros
10 *
11 * These macros are used to express state changes in easily readable form.
12 *
13 * The NS macros expand to a mask and a value, that can be bit ored onto the
14 * current state as soon as the spinlock (req_lock) was taken.
15 *
16 * The _NS macros are used for state functions that get called with the
17 * spinlock. These macros expand directly to the new state value.
18 *
19 * Besides the basic forms NS() and _NS() additional _?NS[23] are defined
20 * to express state changes that affect more than one aspect of the state.
21 *
22 * E.g. NS2(conn, C_CONNECTED, peer, R_SECONDARY)
23 * Means that the network connection was established and that the peer
24 * is in secondary role.
25 */
26#define role_MASK R_MASK
27#define peer_MASK R_MASK
28#define disk_MASK D_MASK
29#define pdsk_MASK D_MASK
30#define conn_MASK C_MASK
31#define susp_MASK 1
32#define user_isp_MASK 1
33#define aftr_isp_MASK 1
34#define susp_nod_MASK 1
35#define susp_fen_MASK 1
36
37#define NS(T, S) \
38 ({ union drbd_state mask; mask.i = 0; mask.T = T##_MASK; mask; }), \
39 ({ union drbd_state val; val.i = 0; val.T = (S); val; })
40#define NS2(T1, S1, T2, S2) \
41 ({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \
42 mask.T2 = T2##_MASK; mask; }), \
43 ({ union drbd_state val; val.i = 0; val.T1 = (S1); \
44 val.T2 = (S2); val; })
45#define NS3(T1, S1, T2, S2, T3, S3) \
46 ({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \
47 mask.T2 = T2##_MASK; mask.T3 = T3##_MASK; mask; }), \
48 ({ union drbd_state val; val.i = 0; val.T1 = (S1); \
49 val.T2 = (S2); val.T3 = (S3); val; })
50
51#define _NS(D, T, S) \
52 D, ({ union drbd_state __ns; __ns = drbd_read_state(D); __ns.T = (S); __ns; })
53#define _NS2(D, T1, S1, T2, S2) \
54 D, ({ union drbd_state __ns; __ns = drbd_read_state(D); __ns.T1 = (S1); \
55 __ns.T2 = (S2); __ns; })
56#define _NS3(D, T1, S1, T2, S2, T3, S3) \
57 D, ({ union drbd_state __ns; __ns = drbd_read_state(D); __ns.T1 = (S1); \
58 __ns.T2 = (S2); __ns.T3 = (S3); __ns; })
59
60enum chg_state_flags {
61 CS_HARD = 1 << 0,
62 CS_VERBOSE = 1 << 1,
63 CS_WAIT_COMPLETE = 1 << 2,
64 CS_SERIALIZE = 1 << 3,
65 CS_ORDERED = CS_WAIT_COMPLETE + CS_SERIALIZE,
66 CS_LOCAL_ONLY = 1 << 4, /* Do not consider a device pair wide state change */
67 CS_DC_ROLE = 1 << 5, /* DC = display as connection state change */
68 CS_DC_PEER = 1 << 6,
69 CS_DC_CONN = 1 << 7,
70 CS_DC_DISK = 1 << 8,
71 CS_DC_PDSK = 1 << 9,
72 CS_DC_SUSP = 1 << 10,
73 CS_DC_MASK = CS_DC_ROLE + CS_DC_PEER + CS_DC_CONN + CS_DC_DISK + CS_DC_PDSK,
74 CS_IGN_OUTD_FAIL = 1 << 11,
75
76 /* Make sure no meta data IO is in flight, by calling
77 * drbd_md_get_buffer(). Used for graceful detach. */
78 CS_INHIBIT_MD_IO = 1 << 12,
79};
80
81/* drbd_dev_state and drbd_state are different types. This is to stress the
82 small difference. There is no suspended flag (.susp), and no suspended
83 while fence handler runs flas (susp_fen). */
84union drbd_dev_state {
85 struct {
86#if defined(__LITTLE_ENDIAN_BITFIELD)
87 unsigned role:2 ; /* 3/4 primary/secondary/unknown */
88 unsigned peer:2 ; /* 3/4 primary/secondary/unknown */
89 unsigned conn:5 ; /* 17/32 cstates */
90 unsigned disk:4 ; /* 8/16 from D_DISKLESS to D_UP_TO_DATE */
91 unsigned pdsk:4 ; /* 8/16 from D_DISKLESS to D_UP_TO_DATE */
92 unsigned _unused:1 ;
93 unsigned aftr_isp:1 ; /* isp .. imposed sync pause */
94 unsigned peer_isp:1 ;
95 unsigned user_isp:1 ;
96 unsigned _pad:11; /* 0 unused */
97#elif defined(__BIG_ENDIAN_BITFIELD)
98 unsigned _pad:11;
99 unsigned user_isp:1 ;
100 unsigned peer_isp:1 ;
101 unsigned aftr_isp:1 ; /* isp .. imposed sync pause */
102 unsigned _unused:1 ;
103 unsigned pdsk:4 ; /* 8/16 from D_DISKLESS to D_UP_TO_DATE */
104 unsigned disk:4 ; /* 8/16 from D_DISKLESS to D_UP_TO_DATE */
105 unsigned conn:5 ; /* 17/32 cstates */
106 unsigned peer:2 ; /* 3/4 primary/secondary/unknown */
107 unsigned role:2 ; /* 3/4 primary/secondary/unknown */
108#else
109# error "this endianess is not supported"
110#endif
111 };
112 unsigned int i;
113};
114
115extern enum drbd_state_rv drbd_change_state(struct drbd_device *device,
116 enum chg_state_flags f,
117 union drbd_state mask,
118 union drbd_state val);
119extern void drbd_force_state(struct drbd_device *, union drbd_state,
120 union drbd_state);
121extern enum drbd_state_rv _drbd_request_state(struct drbd_device *,
122 union drbd_state,
123 union drbd_state,
124 enum chg_state_flags);
125
126extern enum drbd_state_rv
127_drbd_request_state_holding_state_mutex(struct drbd_device *, union drbd_state,
128 union drbd_state, enum chg_state_flags);
129
130extern enum drbd_state_rv _drbd_set_state(struct drbd_device *, union drbd_state,
131 enum chg_state_flags,
132 struct completion *done);
133extern void print_st_err(struct drbd_device *, union drbd_state,
134 union drbd_state, enum drbd_state_rv);
135
136enum drbd_state_rv
137_conn_request_state(struct drbd_connection *connection, union drbd_state mask, union drbd_state val,
138 enum chg_state_flags flags);
139
140enum drbd_state_rv
141conn_request_state(struct drbd_connection *connection, union drbd_state mask, union drbd_state val,
142 enum chg_state_flags flags);
143
144extern void drbd_resume_al(struct drbd_device *device);
145extern bool conn_all_vols_unconf(struct drbd_connection *connection);
146
147/**
148 * drbd_request_state() - Request a state change
149 * @device: DRBD device.
150 * @mask: mask of state bits to change.
151 * @val: value of new state bits.
152 *
153 * This is the most graceful way of requesting a state change. It is verbose
154 * quite verbose in case the state change is not possible, and all those
155 * state changes are globally serialized.
156 */
157static inline int drbd_request_state(struct drbd_device *device,
158 union drbd_state mask,
159 union drbd_state val)
160{
161 return _drbd_request_state(device, mask, val, CS_VERBOSE + CS_ORDERED);
162}
163
164/* for use in adm_detach() (drbd_adm_detach(), drbd_adm_down()) */
165int drbd_request_detach_interruptible(struct drbd_device *device);
166
167enum drbd_role conn_highest_role(struct drbd_connection *connection);
168enum drbd_role conn_highest_peer(struct drbd_connection *connection);
169enum drbd_disk_state conn_highest_disk(struct drbd_connection *connection);
170enum drbd_disk_state conn_lowest_disk(struct drbd_connection *connection);
171enum drbd_disk_state conn_highest_pdsk(struct drbd_connection *connection);
172enum drbd_conns conn_lowest_conn(struct drbd_connection *connection);
173
174#endif
175

source code of linux/drivers/block/drbd/drbd_state.h