xref: /aosp_15_r20/external/ublksrv/nbd/nbd.h (revision 94c4a1e103eb1715230460aab379dff275992c20)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * 1999 Copyright (C) Pavel Machek, [email protected]. This code is GPL.
4  * 1999/11/04 Copyright (C) 1999 VMware, Inc. (Regis "HPReg" Duchesne)
5  *            Made nbd_end_request() use the io_request_lock
6  * 2001 Copyright (C) Steven Whitehouse
7  *            New nbd_end_request() for compatibility with new linux block
8  *            layer code.
9  * 2003/06/24 Louis D. Langholtz <[email protected]>
10  *            Removed unneeded blksize_bits field from nbd_device struct.
11  *            Cleanup PARANOIA usage & code.
12  * 2004/02/19 Paul Clements
13  *            Removed PARANOIA, plus various cleanup and comments
14  */
15 
16 #ifndef LINUX_NBD_H
17 #define LINUX_NBD_H
18 
19 #include <stdbool.h>
20 
21 #ifdef __cplusplus
22 extern "C" {
23 #endif
24 
25 //#include <linux/types.h>
26 
27 #if 0
28 #define NBD_SET_SOCK	_IO( 0xab, 0 )
29 #define NBD_SET_BLKSIZE	_IO( 0xab, 1 )
30 #define NBD_SET_SIZE	_IO( 0xab, 2 )
31 #define NBD_DO_IT	_IO( 0xab, 3 )
32 #define NBD_CLEAR_SOCK	_IO( 0xab, 4 )
33 #define NBD_CLEAR_QUE	_IO( 0xab, 5 )
34 #define NBD_PRINT_DEBUG	_IO( 0xab, 6 )
35 #define NBD_SET_SIZE_BLOCKS	_IO( 0xab, 7 )
36 #define NBD_DISCONNECT  _IO( 0xab, 8 )
37 #define NBD_SET_TIMEOUT _IO( 0xab, 9 )
38 #define NBD_SET_FLAGS _IO( 0xab, 10 )
39 #endif
40 
41 enum {
42 	NBD_CMD_READ = 0,
43 	NBD_CMD_WRITE = 1,
44 	NBD_CMD_DISC = 2,
45 	NBD_CMD_FLUSH = 3,
46 	NBD_CMD_TRIM = 4,
47 	NBD_CMD_CACHE = 5,
48 	NBD_CMD_WRITE_ZEROES = 6,
49 	NBD_CMD_BLOCK_STATUS = 7,
50 	NBD_CMD_RESIZE = 8
51 };
52 
53 #define NBD_CMD_MASK_COMMAND 0x0000ffff
54 #define NBD_CMD_SHIFT (16)
55 #define NBD_CMD_FLAG_FUA ((1 << 0) << NBD_CMD_SHIFT)
56 #define NBD_CMD_FLAG_NO_HOLE ((1 << 1) << NBD_CMD_SHIFT)
57 
58 /* values for flags field */
59 #define NBD_FLAG_HAS_FLAGS	(1 << 0)	/* Flags are there */
60 #define NBD_FLAG_READ_ONLY	(1 << 1)	/* Device is read-only */
61 #define NBD_FLAG_SEND_FLUSH	(1 << 2)	/* Send FLUSH */
62 #define NBD_FLAG_SEND_FUA	(1 << 3)	/* Send FUA (Force Unit Access) */
63 #define NBD_FLAG_ROTATIONAL	(1 << 4)	/* Use elevator algorithm - rotational media */
64 #define NBD_FLAG_SEND_TRIM	(1 << 5)	/* Send TRIM (discard) */
65 #define NBD_FLAG_SEND_WRITE_ZEROES (1 << 6) 	/* Send NBD_CMD_WRITE_ZEROES */
66 #define NBD_FLAG_CAN_MULTI_CONN	(1 << 8)	/* multiple connections are okay */
67 
68 /* from libnbd/lib/nbd-protocol.h */
69 #define NBD_FLAG_SEND_DF           (1 << 7)
70 #define NBD_FLAG_SEND_CACHE        (1 << 10)
71 #define NBD_FLAG_SEND_FAST_ZERO    (1 << 11)
72 
73 #define nbd_cmd(req) ((req)->cmd[0])
74 
75 /* userspace doesn't need the nbd_device structure */
76 
77 /* These are sent over the network in the request/reply magic fields */
78 
79 #define NBD_REQUEST_MAGIC 0x25609513
80 #define NBD_REPLY_MAGIC 0x67446698
81 #define NBD_STRUCTURED_REPLY_MAGIC 0x668e33ef
82 
83 /* for the trace log, not part of the protocol, not sent over the wire */
84 #define NBD_TRACELOG_MAGIC 0x25609514
85 
86 #define NBD_OPT_REPLY_MAGIC 0x3e889045565a9LL
87 
88 /*
89  * This is the packet used for communication between client and
90  * server. All data are in network byte order.
91  */
92 struct nbd_request {
93 	uint32_t magic;
94 	uint32_t type;	/* == READ || == WRITE 	*/
95 	char handle[8];
96 	uint64_t from;
97 	uint32_t len;
98 } __attribute__ ((packed));
99 
100 /*
101  * This is the reply packet that nbd-server sends back to the client after
102  * it has completed an I/O request (or an error occurs).
103  */
104 struct nbd_reply {
105 	uint32_t magic;
106 	uint32_t error;		/* 0 = ok, else error	*/
107 	char handle[8];		/* handle you got from request	*/
108 };
109 
110 extern int opennet(const char *name, const char* portstr, int sdp);
111 extern int openunix(const char *path);
112 extern void negotiate(int *sockp, u64 *rsize64, uint16_t *flags, char* name,
113 		uint32_t needed_flags, uint32_t client_flags, uint32_t do_opts,
114 		char *certfile, char *keyfile, char *cacertfile,
115 		char *tlshostname, bool tls, bool can_opt_go);
116 
117 #ifdef __cplusplus
118 }
119 #endif
120 #endif
121