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 */ 15 16 #ifndef _UAPILINUX_NBD_H 17 #define _UAPILINUX_NBD_H 18 19 #include <linux/types.h> 20 21 #define NBD_SET_SOCK _IO( 0xab, 0 ) 22 #define NBD_SET_BLKSIZE _IO( 0xab, 1 ) 23 #define NBD_SET_SIZE _IO( 0xab, 2 ) 24 #define NBD_DO_IT _IO( 0xab, 3 ) 25 #define NBD_CLEAR_SOCK _IO( 0xab, 4 ) 26 #define NBD_CLEAR_QUE _IO( 0xab, 5 ) 27 #define NBD_PRINT_DEBUG _IO( 0xab, 6 ) 28 #define NBD_SET_SIZE_BLOCKS _IO( 0xab, 7 ) 29 #define NBD_DISCONNECT _IO( 0xab, 8 ) 30 #define NBD_SET_TIMEOUT _IO( 0xab, 9 ) 31 #define NBD_SET_FLAGS _IO( 0xab, 10) 32 33 enum { 34 NBD_CMD_READ = 0, 35 NBD_CMD_WRITE = 1, 36 NBD_CMD_DISC = 2, 37 NBD_CMD_FLUSH = 3, 38 NBD_CMD_TRIM = 4 39 }; 40 41 /* values for flags field, these are server interaction specific. */ 42 #define NBD_FLAG_HAS_FLAGS (1 << 0) /* nbd-server supports flags */ 43 #define NBD_FLAG_READ_ONLY (1 << 1) /* device is read-only */ 44 #define NBD_FLAG_SEND_FLUSH (1 << 2) /* can flush writeback cache */ 45 #define NBD_FLAG_SEND_FUA (1 << 3) /* send FUA (forced unit access) */ 46 /* there is a gap here to match userspace */ 47 #define NBD_FLAG_SEND_TRIM (1 << 5) /* send trim/discard */ 48 #define NBD_FLAG_CAN_MULTI_CONN (1 << 8) /* Server supports multiple connections per export. */ 49 50 /* values for cmd flags in the upper 16 bits of request type */ 51 #define NBD_CMD_FLAG_FUA (1 << 16) /* FUA (forced unit access) op */ 52 53 /* These are client behavior specific flags. */ 54 #define NBD_CFLAG_DESTROY_ON_DISCONNECT (1 << 0) /* delete the nbd device on 55 disconnect. */ 56 #define NBD_CFLAG_DISCONNECT_ON_CLOSE (1 << 1) /* disconnect the nbd device on 57 * close by last opener. 58 */ 59 60 /* userspace doesn't need the nbd_device structure */ 61 62 /* These are sent over the network in the request/reply magic fields */ 63 64 #define NBD_REQUEST_MAGIC 0x25609513 65 #define NBD_REPLY_MAGIC 0x67446698 66 /* Do *not* use magics: 0x12560953 0x96744668. */ 67 68 /* 69 * This is the packet used for communication between client and 70 * server. All data are in network byte order. 71 */ 72 struct nbd_request { 73 __be32 magic; 74 __be32 type; /* == READ || == WRITE */ 75 char handle[8]; 76 __be64 from; 77 __be32 len; 78 } __attribute__((packed)); 79 80 /* 81 * This is the reply packet that nbd-server sends back to the client after 82 * it has completed an I/O request (or an error occurs). 83 */ 84 struct nbd_reply { 85 __be32 magic; 86 __be32 error; /* 0 = ok, else error */ 87 char handle[8]; /* handle you got from request */ 88 }; 89 #endif /* _UAPILINUX_NBD_H */ 90