drivers/block/drbd/drbd_state.h

Source file repositories/reference/linux-study-clean/drivers/block/drbd/drbd_state.h

File Facts

System
Linux kernel
Corpus path
drivers/block/drbd/drbd_state.h
Extension
.h
Size
6505 bytes
Lines
175
Domain
Driver Families
Bucket
drivers/block
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

#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,

	/* Make sure no meta data IO is in flight, by calling
	 * drbd_md_get_buffer().  Used for graceful detach. */
	CS_INHIBIT_MD_IO = 1 << 12,
};

/* 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 */

Annotation

Implementation Notes