summaryrefslogtreecommitdiffstats
path: root/kernel/drivers/block/drbd/drbd_state.h
blob: 7f53c40823cd581e28279b9ef046a07af54a974e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
#ifndef DRBD_STATE_H
#define DRBD_STATE_H

struct drbd_device;
struct drbd_connection;

/**
 * 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_device *device,
					    enum chg_state_flags f,
					    union drbd_state mask,
					    union drbd_state val);
extern void drbd_force_state(struct drbd_device *, union drbd_state,
			union drbd_state);
extern enum drbd_state_rv _drbd_request_state(struct drbd_device *,
					      union drbd_state,
					      union drbd_state,
					      enum chg_state_flags);

extern enum drbd_state_rv
_drbd_request_state_holding_state_mutex(struct drbd_device *, union drbd_state,
					union drbd_state, enum chg_state_flags);

extern enum drbd_state_rv __drbd_set_state(struct drbd_device *, union drbd_state,
					   enum chg_state_flags,
					   struct completion *done);
extern void print_st_err(struct drbd_device *, union drbd_state,
			union drbd_state, int);

enum drbd_state_rv
_conn_request_state(struct drbd_connection *connection, union drbd_state mask, union drbd_state val,
		    enum chg_state_flags flags);

enum drbd_state_rv
conn_request_state(struct drbd_connection *connection, union drbd_state mask, union drbd_state val,
		   enum chg_state_flags flags);

extern void drbd_resume_al(struct drbd_device *device);
extern bool conn_all_vols_unconf(struct drbd_connection *connection);

/**
 * drbd_request_state() - Reqest a state change
 * @device:	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_device *device,
				     union drbd_state mask,
				     union drbd_state val)
{
	return _drbd_request_state(device, mask, val, CS_VERBOSE + CS_ORDERED);
}

enum drbd_role conn_highest_role(struct drbd_connection *connection);
enum drbd_role conn_highest_peer(struct drbd_connection *connection);
enum drbd_disk_state conn_highest_disk(struct drbd_connection *connection);
enum drbd_disk_state conn_lowest_disk(struct drbd_connection *connection);
enum drbd_disk_state conn_highest_pdsk(struct drbd_connection *connection);
enum drbd_conns conn_lowest_conn(struct drbd_connection *connection);

#endif