379 lines
11 KiB
C
379 lines
11 KiB
C
|
#ifndef __DRBD_PROTOCOL_H
|
||
|
|
#define __DRBD_PROTOCOL_H
|
||
|
|
|
||
|
|
enum drbd_packet {
|
||
|
|
/* receiver (data socket) */
|
||
|
|
P_DATA = 0x00,
|
||
|
|
P_DATA_REPLY = 0x01, /* Response to P_DATA_REQUEST */
|
||
|
|
P_RS_DATA_REPLY = 0x02, /* Response to P_RS_DATA_REQUEST */
|
||
|
|
P_BARRIER = 0x03,
|
||
|
|
P_BITMAP = 0x04,
|
||
|
|
P_BECOME_SYNC_TARGET = 0x05,
|
||
|
|
P_BECOME_SYNC_SOURCE = 0x06,
|
||
|
|
P_UNPLUG_REMOTE = 0x07, /* Used at various times to hint the peer */
|
||
|
|
P_DATA_REQUEST = 0x08, /* Used to ask for a data block */
|
||
|
|
P_RS_DATA_REQUEST = 0x09, /* Used to ask for a data block for resync */
|
||
|
|
P_SYNC_PARAM = 0x0a,
|
||
|
|
P_PROTOCOL = 0x0b,
|
||
|
|
P_UUIDS = 0x0c,
|
||
|
|
P_SIZES = 0x0d,
|
||
|
|
P_STATE = 0x0e,
|
||
|
|
P_SYNC_UUID = 0x0f,
|
||
|
|
P_AUTH_CHALLENGE = 0x10,
|
||
|
|
P_AUTH_RESPONSE = 0x11,
|
||
|
|
P_STATE_CHG_REQ = 0x12,
|
||
|
|
|
||
|
|
/* (meta socket) */
|
||
|
|
P_PING = 0x13,
|
||
|
|
P_PING_ACK = 0x14,
|
||
|
|
P_RECV_ACK = 0x15, /* Used in protocol B */
|
||
|
|
P_WRITE_ACK = 0x16, /* Used in protocol C */
|
||
|
|
P_RS_WRITE_ACK = 0x17, /* Is a P_WRITE_ACK, additionally call set_in_sync(). */
|
||
|
|
P_SUPERSEDED = 0x18, /* Used in proto C, two-primaries conflict detection */
|
||
|
|
P_NEG_ACK = 0x19, /* Sent if local disk is unusable */
|
||
|
|
P_NEG_DREPLY = 0x1a, /* Local disk is broken... */
|
||
|
|
P_NEG_RS_DREPLY = 0x1b, /* Local disk is broken... */
|
||
|
|
P_BARRIER_ACK = 0x1c,
|
||
|
|
P_STATE_CHG_REPLY = 0x1d,
|
||
|
|
|
||
|
|
/* "new" commands, no longer fitting into the ordering scheme above */
|
||
|
|
|
||
|
|
P_OV_REQUEST = 0x1e, /* data socket */
|
||
|
|
P_OV_REPLY = 0x1f,
|
||
|
|
P_OV_RESULT = 0x20, /* meta socket */
|
||
|
|
P_CSUM_RS_REQUEST = 0x21, /* data socket */
|
||
|
|
P_RS_IS_IN_SYNC = 0x22, /* meta socket */
|
||
|
|
P_SYNC_PARAM89 = 0x23, /* data socket, protocol version 89 replacement for P_SYNC_PARAM */
|
||
|
|
P_COMPRESSED_BITMAP = 0x24, /* compressed or otherwise encoded bitmap transfer */
|
||
|
|
/* P_CKPT_FENCE_REQ = 0x25, * currently reserved for protocol D */
|
||
|
|
/* P_CKPT_DISABLE_REQ = 0x26, * currently reserved for protocol D */
|
||
|
|
P_DELAY_PROBE = 0x27, /* is used on BOTH sockets */
|
||
|
|
P_OUT_OF_SYNC = 0x28, /* Mark as out of sync (Outrunning), data socket */
|
||
|
|
P_RS_CANCEL = 0x29, /* meta: Used to cancel RS_DATA_REQUEST packet by SyncSource */
|
||
|
|
P_CONN_ST_CHG_REQ = 0x2a, /* data sock: Connection wide state request */
|
||
|
|
P_CONN_ST_CHG_REPLY = 0x2b, /* meta sock: Connection side state req reply */
|
||
|
|
P_RETRY_WRITE = 0x2c, /* Protocol C: retry conflicting write request */
|
||
|
|
P_PROTOCOL_UPDATE = 0x2d, /* data sock: is used in established connections */
|
||
|
|
/* 0x2e to 0x30 reserved, used in drbd 9 */
|
||
|
|
|
||
|
|
/* REQ_DISCARD. We used "discard" in different contexts before,
|
||
|
|
* which is why I chose TRIM here, to disambiguate. */
|
||
|
|
P_TRIM = 0x31,
|
||
|
|
|
||
|
|
/* Only use these two if both support FF_THIN_RESYNC */
|
||
|
|
P_RS_THIN_REQ = 0x32, /* Request a block for resync or reply P_RS_DEALLOCATED */
|
||
|
|
P_RS_DEALLOCATED = 0x33, /* Contains only zeros on sync source node */
|
||
|
|
|
||
|
|
/* REQ_WRITE_SAME.
|
||
|
|
* On a receiving side without REQ_WRITE_SAME,
|
||
|
|
* we may fall back to an opencoded loop instead. */
|
||
|
|
P_WSAME = 0x34,
|
||
|
|
|
||
|
|
P_MAY_IGNORE = 0x100, /* Flag to test if (cmd > P_MAY_IGNORE) ... */
|
||
|
|
P_MAX_OPT_CMD = 0x101,
|
||
|
|
|
||
|
|
/* special command ids for handshake */
|
||
|
|
|
||
|
|
P_INITIAL_META = 0xfff1, /* First Packet on the MetaSock */
|
||
|
|
P_INITIAL_DATA = 0xfff2, /* First Packet on the Socket */
|
||
|
|
|
||
|
|
P_CONNECTION_FEATURES = 0xfffe /* FIXED for the next century! */
|
||
|
|
};
|
||
|
|
|
||
|
|
#ifndef __packed
|
||
|
|
#define __packed __attribute__((packed))
|
||
|
|
#endif
|
||
|
|
|
||
|
|
/* This is the layout for a packet on the wire.
|
||
|
|
* The byteorder is the network byte order.
|
||
|
|
* (except block_id and barrier fields.
|
||
|
|
* these are pointers to local structs
|
||
|
|
* and have no relevance for the partner,
|
||
|
|
* which just echoes them as received.)
|
||
|
|
*
|
||
|
|
* NOTE that the payload starts at a long aligned offset,
|
||
|
|
* regardless of 32 or 64 bit arch!
|
||
|
|
*/
|
||
|
|
struct p_header80 {
|
||
|
|
u32 magic;
|
||
|
|
u16 command;
|
||
|
|
u16 length; /* bytes of data after this header */
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
/* Header for big packets, Used for data packets exceeding 64kB */
|
||
|
|
struct p_header95 {
|
||
|
|
u16 magic; /* use DRBD_MAGIC_BIG here */
|
||
|
|
u16 command;
|
||
|
|
u32 length;
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_header100 {
|
||
|
|
u32 magic;
|
||
|
|
u16 volume;
|
||
|
|
u16 command;
|
||
|
|
u32 length;
|
||
|
|
u32 pad;
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
/* These defines must not be changed without changing the protocol version.
|
||
|
|
* New defines may only be introduced together with protocol version bump or
|
||
|
|
* new protocol feature flags.
|
||
|
|
*/
|
||
|
|
#define DP_HARDBARRIER 1 /* no longer used */
|
||
|
|
#define DP_RW_SYNC 2 /* equals REQ_SYNC */
|
||
|
|
#define DP_MAY_SET_IN_SYNC 4
|
||
|
|
#define DP_UNPLUG 8 /* not used anymore */
|
||
|
|
#define DP_FUA 16 /* equals REQ_FUA */
|
||
|
|
#define DP_FLUSH 32 /* equals REQ_PREFLUSH */
|
||
|
|
#define DP_DISCARD 64 /* equals REQ_DISCARD */
|
||
|
|
#define DP_SEND_RECEIVE_ACK 128 /* This is a proto B write request */
|
||
|
|
#define DP_SEND_WRITE_ACK 256 /* This is a proto C write request */
|
||
|
|
#define DP_WSAME 512 /* equiv. REQ_WRITE_SAME */
|
||
|
|
|
||
|
|
struct p_data {
|
||
|
|
u64 sector; /* 64 bits sector number */
|
||
|
|
u64 block_id; /* to identify the request in protocol B&C */
|
||
|
|
u32 seq_num;
|
||
|
|
u32 dp_flags;
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_trim {
|
||
|
|
struct p_data p_data;
|
||
|
|
u32 size; /* == bio->bi_size */
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_wsame {
|
||
|
|
struct p_data p_data;
|
||
|
|
u32 size; /* == bio->bi_size */
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* commands which share a struct:
|
||
|
|
* p_block_ack:
|
||
|
|
* P_RECV_ACK (proto B), P_WRITE_ACK (proto C),
|
||
|
|
* P_SUPERSEDED (proto C, two-primaries conflict detection)
|
||
|
|
* p_block_req:
|
||
|
|
* P_DATA_REQUEST, P_RS_DATA_REQUEST
|
||
|
|
*/
|
||
|
|
struct p_block_ack {
|
||
|
|
u64 sector;
|
||
|
|
u64 block_id;
|
||
|
|
u32 blksize;
|
||
|
|
u32 seq_num;
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_block_req {
|
||
|
|
u64 sector;
|
||
|
|
u64 block_id;
|
||
|
|
u32 blksize;
|
||
|
|
u32 pad; /* to multiple of 8 Byte */
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* commands with their own struct for additional fields:
|
||
|
|
* P_CONNECTION_FEATURES
|
||
|
|
* P_BARRIER
|
||
|
|
* P_BARRIER_ACK
|
||
|
|
* P_SYNC_PARAM
|
||
|
|
* ReportParams
|
||
|
|
*/
|
||
|
|
|
||
|
|
/* supports TRIM/DISCARD on the "wire" protocol */
|
||
|
|
#define DRBD_FF_TRIM 1
|
||
|
|
|
||
|
|
/* Detect all-zeros during resync, and rather TRIM/UNMAP/DISCARD those blocks
|
||
|
|
* instead of fully allocate a supposedly thin volume on initial resync */
|
||
|
|
#define DRBD_FF_THIN_RESYNC 2
|
||
|
|
|
||
|
|
/* supports REQ_WRITE_SAME on the "wire" protocol.
|
||
|
|
* Note: this flag is overloaded,
|
||
|
|
* its presence also
|
||
|
|
* - indicates support for 128 MiB "batch bios",
|
||
|
|
* max discard size of 128 MiB
|
||
|
|
* instead of 4M before that.
|
||
|
|
* - indicates that we exchange additional settings in p_sizes
|
||
|
|
* drbd_send_sizes()/receive_sizes()
|
||
|
|
*/
|
||
|
|
#define DRBD_FF_WSAME 4
|
||
|
|
|
||
|
|
struct p_connection_features {
|
||
|
|
u32 protocol_min;
|
||
|
|
u32 feature_flags;
|
||
|
|
u32 protocol_max;
|
||
|
|
|
||
|
|
/* should be more than enough for future enhancements
|
||
|
|
* for now, feature_flags and the reserved array shall be zero.
|
||
|
|
*/
|
||
|
|
|
||
|
|
u32 _pad;
|
||
|
|
u64 reserved[7];
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_barrier {
|
||
|
|
u32 barrier; /* barrier number _handle_ only */
|
||
|
|
u32 pad; /* to multiple of 8 Byte */
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_barrier_ack {
|
||
|
|
u32 barrier;
|
||
|
|
u32 set_size;
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_rs_param {
|
||
|
|
u32 resync_rate;
|
||
|
|
|
||
|
|
/* Since protocol version 88 and higher. */
|
||
|
|
char verify_alg[0];
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_rs_param_89 {
|
||
|
|
u32 resync_rate;
|
||
|
|
/* protocol version 89: */
|
||
|
|
char verify_alg[SHARED_SECRET_MAX];
|
||
|
|
char csums_alg[SHARED_SECRET_MAX];
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_rs_param_95 {
|
||
|
|
u32 resync_rate;
|
||
|
|
char verify_alg[SHARED_SECRET_MAX];
|
||
|
|
char csums_alg[SHARED_SECRET_MAX];
|
||
|
|
u32 c_plan_ahead;
|
||
|
|
u32 c_delay_target;
|
||
|
|
u32 c_fill_target;
|
||
|
|
u32 c_max_rate;
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
enum drbd_conn_flags {
|
||
|
|
CF_DISCARD_MY_DATA = 1,
|
||
|
|
CF_DRY_RUN = 2,
|
||
|
|
};
|
||
|
|
|
||
|
|
struct p_protocol {
|
||
|
|
u32 protocol;
|
||
|
|
u32 after_sb_0p;
|
||
|
|
u32 after_sb_1p;
|
||
|
|
u32 after_sb_2p;
|
||
|
|
u32 conn_flags;
|
||
|
|
u32 two_primaries;
|
||
|
|
|
||
|
|
/* Since protocol version 87 and higher. */
|
||
|
|
char integrity_alg[0];
|
||
|
|
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_uuids {
|
||
|
|
u64 uuid[UI_EXTENDED_SIZE];
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_rs_uuid {
|
||
|
|
u64 uuid;
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
/* optional queue_limits if (agreed_features & DRBD_FF_WSAME)
|
||
|
|
* see also struct queue_limits, as of late 2015 */
|
||
|
|
struct o_qlim {
|
||
|
|
/* we don't need it yet, but we may as well communicate it now */
|
||
|
|
u32 physical_block_size;
|
||
|
|
|
||
|
|
/* so the original in struct queue_limits is unsigned short,
|
||
|
|
* but I'd have to put in padding anyways. */
|
||
|
|
u32 logical_block_size;
|
||
|
|
|
||
|
|
/* One incoming bio becomes one DRBD request,
|
||
|
|
* which may be translated to several bio on the receiving side.
|
||
|
|
* We don't need to communicate chunk/boundary/segment ... limits.
|
||
|
|
*/
|
||
|
|
|
||
|
|
/* various IO hints may be useful with "diskless client" setups */
|
||
|
|
u32 alignment_offset;
|
||
|
|
u32 io_min;
|
||
|
|
u32 io_opt;
|
||
|
|
|
||
|
|
/* We may need to communicate integrity stuff at some point,
|
||
|
|
* but let's not get ahead of ourselves. */
|
||
|
|
|
||
|
|
/* Backend discard capabilities.
|
||
|
|
* Receiving side uses "blkdev_issue_discard()", no need to communicate
|
||
|
|
* more specifics. If the backend cannot do discards, the DRBD peer
|
||
|
|
* may fall back to blkdev_issue_zeroout().
|
||
|
|
*/
|
||
|
|
u8 discard_enabled;
|
||
|
|
u8 discard_zeroes_data;
|
||
|
|
u8 write_same_capable;
|
||
|
|
u8 _pad;
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_sizes {
|
||
|
|
u64 d_size; /* size of disk */
|
||
|
|
u64 u_size; /* user requested size */
|
||
|
|
u64 c_size; /* current exported size */
|
||
|
|
u32 max_bio_size; /* Maximal size of a BIO */
|
||
|
|
u16 queue_order_type; /* not yet implemented in DRBD*/
|
||
|
|
u16 dds_flags; /* use enum dds_flags here. */
|
||
|
|
|
||
|
|
/* optional queue_limits if (agreed_features & DRBD_FF_WSAME) */
|
||
|
|
struct o_qlim qlim[0];
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_state {
|
||
|
|
u32 state;
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_req_state {
|
||
|
|
u32 mask;
|
||
|
|
u32 val;
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_req_state_reply {
|
||
|
|
u32 retcode;
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_drbd06_param {
|
||
|
|
u64 size;
|
||
|
|
u32 state;
|
||
|
|
u32 blksize;
|
||
|
|
u32 protocol;
|
||
|
|
u32 version;
|
||
|
|
u32 gen_cnt[5];
|
||
|
|
u32 bit_map_gen[5];
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_block_desc {
|
||
|
|
u64 sector;
|
||
|
|
u32 blksize;
|
||
|
|
u32 pad; /* to multiple of 8 Byte */
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
/* Valid values for the encoding field.
|
||
|
|
* Bump proto version when changing this. */
|
||
|
|
enum drbd_bitmap_code {
|
||
|
|
/* RLE_VLI_Bytes = 0,
|
||
|
|
* and other bit variants had been defined during
|
||
|
|
* algorithm evaluation. */
|
||
|
|
RLE_VLI_Bits = 2,
|
||
|
|
};
|
||
|
|
|
||
|
|
struct p_compressed_bm {
|
||
|
|
/* (encoding & 0x0f): actual encoding, see enum drbd_bitmap_code
|
||
|
|
* (encoding & 0x80): polarity (set/unset) of first runlength
|
||
|
|
* ((encoding >> 4) & 0x07): pad_bits, number of trailing zero bits
|
||
|
|
* used to pad up to head.length bytes
|
||
|
|
*/
|
||
|
|
u8 encoding;
|
||
|
|
|
||
|
|
u8 code[0];
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
struct p_delay_probe93 {
|
||
|
|
u32 seq_num; /* sequence number to match the two probe packets */
|
||
|
|
u32 offset; /* usecs the probe got sent after the reference time point */
|
||
|
|
} __packed;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Bitmap packets need to fit within a single page on the sender and receiver,
|
||
|
|
* so we are limited to 4 KiB (and not to PAGE_SIZE, which can be bigger).
|
||
|
|
*/
|
||
|
|
#define DRBD_SOCKET_BUFFER_SIZE 4096
|
||
|
|
|
||
|
|
#endif /* __DRBD_PROTOCOL_H */
|