1 | /* SPDX-License-Identifier: GPL-1.0+ WITH Linux-syscall-note */ |
2 | /* |
3 | * 1999 Copyright (C) Pavel Machek, pavel@ucw.cz. 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 <ldl@aros.net> |
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 | * 2023 Copyright Red Hat |
15 | * Link to userspace extensions, favor cookie over handle. |
16 | */ |
17 | |
18 | #ifndef _UAPILINUX_NBD_H |
19 | #define _UAPILINUX_NBD_H |
20 | |
21 | #include <linux/types.h> |
22 | |
23 | #define NBD_SET_SOCK _IO( 0xab, 0 ) |
24 | #define NBD_SET_BLKSIZE _IO( 0xab, 1 ) |
25 | #define NBD_SET_SIZE _IO( 0xab, 2 ) |
26 | #define NBD_DO_IT _IO( 0xab, 3 ) |
27 | #define NBD_CLEAR_SOCK _IO( 0xab, 4 ) |
28 | #define NBD_CLEAR_QUE _IO( 0xab, 5 ) |
29 | #define NBD_PRINT_DEBUG _IO( 0xab, 6 ) |
30 | #define NBD_SET_SIZE_BLOCKS _IO( 0xab, 7 ) |
31 | #define NBD_DISCONNECT _IO( 0xab, 8 ) |
32 | #define NBD_SET_TIMEOUT _IO( 0xab, 9 ) |
33 | #define NBD_SET_FLAGS _IO( 0xab, 10) |
34 | |
35 | /* |
36 | * See also https://github.com/NetworkBlockDevice/nbd/blob/master/doc/proto.md |
37 | * for additional userspace extensions not yet utilized in the kernel module. |
38 | */ |
39 | |
40 | enum { |
41 | NBD_CMD_READ = 0, |
42 | NBD_CMD_WRITE = 1, |
43 | NBD_CMD_DISC = 2, |
44 | NBD_CMD_FLUSH = 3, |
45 | NBD_CMD_TRIM = 4 |
46 | /* userspace defines additional extension commands */ |
47 | }; |
48 | |
49 | /* values for flags field, these are server interaction specific. */ |
50 | #define NBD_FLAG_HAS_FLAGS (1 << 0) /* nbd-server supports flags */ |
51 | #define NBD_FLAG_READ_ONLY (1 << 1) /* device is read-only */ |
52 | #define NBD_FLAG_SEND_FLUSH (1 << 2) /* can flush writeback cache */ |
53 | #define NBD_FLAG_SEND_FUA (1 << 3) /* send FUA (forced unit access) */ |
54 | /* there is a gap here to match userspace */ |
55 | #define NBD_FLAG_SEND_TRIM (1 << 5) /* send trim/discard */ |
56 | #define NBD_FLAG_CAN_MULTI_CONN (1 << 8) /* Server supports multiple connections per export. */ |
57 | |
58 | /* values for cmd flags in the upper 16 bits of request type */ |
59 | #define NBD_CMD_FLAG_FUA (1 << 16) /* FUA (forced unit access) op */ |
60 | |
61 | /* These are client behavior specific flags. */ |
62 | #define NBD_CFLAG_DESTROY_ON_DISCONNECT (1 << 0) /* delete the nbd device on |
63 | disconnect. */ |
64 | #define NBD_CFLAG_DISCONNECT_ON_CLOSE (1 << 1) /* disconnect the nbd device on |
65 | * close by last opener. |
66 | */ |
67 | |
68 | /* userspace doesn't need the nbd_device structure */ |
69 | |
70 | /* These are sent over the network in the request/reply magic fields */ |
71 | |
72 | #define NBD_REQUEST_MAGIC 0x25609513 |
73 | #define NBD_REPLY_MAGIC 0x67446698 |
74 | /* Do *not* use magics: 0x12560953 0x96744668. */ |
75 | /* magic 0x668e33ef for structured reply not supported by kernel yet */ |
76 | |
77 | /* |
78 | * This is the packet used for communication between client and |
79 | * server. All data are in network byte order. |
80 | */ |
81 | struct nbd_request { |
82 | __be32 magic; /* NBD_REQUEST_MAGIC */ |
83 | __be32 type; /* See NBD_CMD_* */ |
84 | union { |
85 | __be64 cookie; /* Opaque identifier for request */ |
86 | char handle[8]; /* older spelling of cookie */ |
87 | }; |
88 | __be64 from; |
89 | __be32 len; |
90 | } __attribute__((packed)); |
91 | |
92 | /* |
93 | * This is the reply packet that nbd-server sends back to the client after |
94 | * it has completed an I/O request (or an error occurs). |
95 | */ |
96 | struct nbd_reply { |
97 | __be32 magic; /* NBD_REPLY_MAGIC */ |
98 | __be32 error; /* 0 = ok, else error */ |
99 | union { |
100 | __be64 cookie; /* Opaque identifier from request */ |
101 | char handle[8]; /* older spelling of cookie */ |
102 | }; |
103 | }; |
104 | #endif /* _UAPILINUX_NBD_H */ |
105 | |