drbd: Split off on-the-wire protocol definitions

Keep the protocol definitions separate from the kernel code; they are useful in
their own right.
Signed-off-by: NAndreas Gruenbacher <agruen@linbit.com>
Signed-off-by: NPhilipp Reisner <philipp.reisner@linbit.com>

drivers/block/drbd/drbd_int.h

@@ -46,6 +46,7 @@
 #include <linux/drbd_genl_api.h>
 #include <linux/drbd.h>
 #include "drbd_state.h"
+#include "drbd_protocol.h"
 
 #ifdef __CHECKER__
 # define __protected_by(x)       __attribute__((require_context(x,1,999,"rdwr")))
@@ -168,72 +169,6 @@ extern struct ratelimit_state drbd_ratelimit_state;
 extern struct idr minors; /* RCU, updates: genl_lock() */
 extern struct list_head drbd_tconns; /* RCU, updates: genl_lock() */
 
-/* on the wire */
-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,
-
-	/* asender (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 */
-
-	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! */
-};
-
 extern const char *cmdname(enum drbd_packet cmd);
 
 /* for sending/receiving the bitmap,
@@ -276,234 +211,8 @@ static inline void bm_xfer_ctx_bit_to_word_offset(struct bm_xfer_ctx *c)
 #endif
 }
 
-#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;
-
 extern unsigned int drbd_header_size(struct drbd_tconn *tconn);
 
-/* these defines must not be changed without changing the protocol version */
-#define DP_HARDBARRIER	      1 /* depricated */
-#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_FLUSH   */
-#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 */
-
-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;
-
-/*
- * 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
- */
-
-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;
-
-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. */
-} __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
-
 /**********************************************************************/
 enum drbd_thread_state {
 	NONE,

drivers/block/drbd/drbd_main.c

@@ -52,6 +52,7 @@
 
 #include <linux/drbd_limits.h>
 #include "drbd_int.h"
+#include "drbd_protocol.h"
 #include "drbd_req.h" /* only for _req_mod in tl_release and tl_clear */
 
 #include "drbd_vli.h"

drivers/block/drbd/drbd_nl.c

@@ -32,6 +32,7 @@
 #include <linux/blkpg.h>
 #include <linux/cpumask.h>
 #include "drbd_int.h"
+#include "drbd_protocol.h"
 #include "drbd_req.h"
 #include "drbd_wrappers.h"
 #include <asm/unaligned.h>

drivers/block/drbd/drbd_protocol.h

+#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,
+
+	/* asender (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 */
+
+	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 */
+#define DP_HARDBARRIER	      1 /* depricated */
+#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_FLUSH   */
+#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 */
+
+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;
+
+/*
+ * 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
+ */
+
+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;
+
+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. */
+} __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 */

drivers/block/drbd/drbd_receiver.c

@@ -44,6 +44,7 @@
 #include <linux/string.h>
 #include <linux/scatterlist.h>
 #include "drbd_int.h"
+#include "drbd_protocol.h"
 #include "drbd_req.h"
 
 #include "drbd_vli.h"

drivers/block/drbd/drbd_state.c

@@ -27,6 +27,7 @@
 
 #include <linux/drbd_limits.h>
 #include "drbd_int.h"
+#include "drbd_protocol.h"
 #include "drbd_req.h"
 
 struct after_state_chg_work {

drivers/block/drbd/drbd_worker.c

@@ -36,6 +36,7 @@
 #include <linux/scatterlist.h>
 
 #include "drbd_int.h"
+#include "drbd_protocol.h"
 #include "drbd_req.h"
 
 static int w_make_ov_request(struct drbd_work *w, int cancel);