1 /* 2 * 1999 Copyright (C) Pavel Machek, pavel@ucw.cz. This code is GPL. 3 * 1999/11/04 Copyright (C) 1999 VMware, Inc. (Regis "HPReg" Duchesne) 4 * Made nbd_end_request() use the io_request_lock 5 * 2001 Copyright (C) Steven Whitehouse 6 * New nbd_end_request() for compatibility with new linux block 7 * layer code. 8 * 2003/06/24 Louis D. Langholtz <ldl@aros.net> 9 * Removed unneeded blksize_bits field from nbd_device struct. 10 * Cleanup PARANOIA usage & code. 11 * 2004/02/19 Paul Clements 12 * Removed PARANOIA, plus various cleanup and comments 13 */ 14 15 #ifndef LINUX_NBD_H 16 #define LINUX_NBD_H 17 18 #include <linux/types.h> 19 20 #define NBD_SET_SOCK _IO( 0xab, 0 ) 21 #define NBD_SET_BLKSIZE _IO( 0xab, 1 ) 22 #define NBD_SET_SIZE _IO( 0xab, 2 ) 23 #define NBD_DO_IT _IO( 0xab, 3 ) 24 #define NBD_CLEAR_SOCK _IO( 0xab, 4 ) 25 #define NBD_CLEAR_QUE _IO( 0xab, 5 ) 26 #define NBD_PRINT_DEBUG _IO( 0xab, 6 ) 27 #define NBD_SET_SIZE_BLOCKS _IO( 0xab, 7 ) 28 #define NBD_DISCONNECT _IO( 0xab, 8 ) 29 #define NBD_SET_TIMEOUT _IO( 0xab, 9 ) 30 31 enum { 32 NBD_CMD_READ = 0, 33 NBD_CMD_WRITE = 1, 34 NBD_CMD_DISC = 2 35 }; 36 37 #define nbd_cmd(req) ((req)->cmd[0]) 38 39 /* userspace doesn't need the nbd_device structure */ 40 #ifdef __KERNEL__ 41 42 #include <linux/wait.h> 43 #include <linux/mutex.h> 44 45 /* values for flags field */ 46 #define NBD_READ_ONLY 0x0001 47 #define NBD_WRITE_NOCHK 0x0002 48 49 struct request; 50 51 struct nbd_device { 52 int flags; 53 int harderror; /* Code of hard error */ 54 struct socket * sock; 55 struct file * file; /* If == NULL, device is not ready, yet */ 56 int magic; 57 58 spinlock_t queue_lock; 59 struct list_head queue_head; /* Requests waiting result */ 60 struct request *active_req; 61 wait_queue_head_t active_wq; 62 struct list_head waiting_queue; /* Requests to be sent */ 63 wait_queue_head_t waiting_wq; 64 65 struct mutex tx_lock; 66 struct gendisk *disk; 67 int blksize; 68 u64 bytesize; 69 pid_t pid; /* pid of nbd-client, if attached */ 70 int xmit_timeout; 71 }; 72 73 #endif 74 75 /* These are sent over the network in the request/reply magic fields */ 76 77 #define NBD_REQUEST_MAGIC 0x25609513 78 #define NBD_REPLY_MAGIC 0x67446698 79 /* Do *not* use magics: 0x12560953 0x96744668. */ 80 81 /* 82 * This is the packet used for communication between client and 83 * server. All data are in network byte order. 84 */ 85 struct nbd_request { 86 __be32 magic; 87 __be32 type; /* == READ || == WRITE */ 88 char handle[8]; 89 __be64 from; 90 __be32 len; 91 } __attribute__((packed)); 92 93 /* 94 * This is the reply packet that nbd-server sends back to the client after 95 * it has completed an I/O request (or an error occurs). 96 */ 97 struct nbd_reply { 98 __be32 magic; 99 __be32 error; /* 0 = ok, else error */ 100 char handle[8]; /* handle you got from request */ 101 }; 102 #endif 103