Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | #define NBD_SET_SOCK _IO( 0xab, 0 ) |
| 19 | #define NBD_SET_BLKSIZE _IO( 0xab, 1 ) |
| 20 | #define NBD_SET_SIZE _IO( 0xab, 2 ) |
| 21 | #define NBD_DO_IT _IO( 0xab, 3 ) |
| 22 | #define NBD_CLEAR_SOCK _IO( 0xab, 4 ) |
| 23 | #define NBD_CLEAR_QUE _IO( 0xab, 5 ) |
| 24 | #define NBD_PRINT_DEBUG _IO( 0xab, 6 ) |
| 25 | #define NBD_SET_SIZE_BLOCKS _IO( 0xab, 7 ) |
| 26 | #define NBD_DISCONNECT _IO( 0xab, 8 ) |
| 27 | |
| 28 | enum { |
| 29 | NBD_CMD_READ = 0, |
| 30 | NBD_CMD_WRITE = 1, |
| 31 | NBD_CMD_DISC = 2 |
| 32 | }; |
| 33 | |
| 34 | #define nbd_cmd(req) ((req)->cmd[0]) |
| 35 | #define MAX_NBD 128 |
| 36 | |
| 37 | /* userspace doesn't need the nbd_device structure */ |
| 38 | #ifdef __KERNEL__ |
| 39 | |
| 40 | /* values for flags field */ |
| 41 | #define NBD_READ_ONLY 0x0001 |
| 42 | #define NBD_WRITE_NOCHK 0x0002 |
| 43 | |
| 44 | struct nbd_device { |
| 45 | int flags; |
| 46 | int harderror; /* Code of hard error */ |
| 47 | struct socket * sock; |
| 48 | struct file * file; /* If == NULL, device is not ready, yet */ |
| 49 | int magic; |
| 50 | spinlock_t queue_lock; |
| 51 | struct list_head queue_head;/* Requests are added here... */ |
| 52 | struct semaphore tx_lock; |
| 53 | struct gendisk *disk; |
| 54 | int blksize; |
| 55 | u64 bytesize; |
| 56 | }; |
| 57 | |
| 58 | #endif |
| 59 | |
| 60 | /* These are sent over the network in the request/reply magic fields */ |
| 61 | |
| 62 | #define NBD_REQUEST_MAGIC 0x25609513 |
| 63 | #define NBD_REPLY_MAGIC 0x67446698 |
| 64 | /* Do *not* use magics: 0x12560953 0x96744668. */ |
| 65 | |
| 66 | /* |
| 67 | * This is the packet used for communication between client and |
| 68 | * server. All data are in network byte order. |
| 69 | */ |
| 70 | struct nbd_request { |
| 71 | u32 magic; |
| 72 | u32 type; /* == READ || == WRITE */ |
| 73 | char handle[8]; |
| 74 | u64 from; |
| 75 | u32 len; |
| 76 | } |
| 77 | #ifdef __GNUC__ |
| 78 | __attribute__ ((packed)) |
| 79 | #endif |
| 80 | ; |
| 81 | |
| 82 | /* |
| 83 | * This is the reply packet that nbd-server sends back to the client after |
| 84 | * it has completed an I/O request (or an error occurs). |
| 85 | */ |
| 86 | struct nbd_reply { |
| 87 | u32 magic; |
| 88 | u32 error; /* 0 = ok, else error */ |
| 89 | char handle[8]; /* handle you got from request */ |
| 90 | }; |
| 91 | #endif |