diff options
Diffstat (limited to 'include/linux/nbd.h')
| -rw-r--r-- | include/linux/nbd.h | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/include/linux/nbd.h b/include/linux/nbd.h new file mode 100644 index 000000000000..090e210e98f0 --- /dev/null +++ b/include/linux/nbd.h @@ -0,0 +1,91 @@ +/* + * 1999 Copyright (C) Pavel Machek, pavel@ucw.cz. This code is GPL. + * 1999/11/04 Copyright (C) 1999 VMware, Inc. (Regis "HPReg" Duchesne) + * Made nbd_end_request() use the io_request_lock + * 2001 Copyright (C) Steven Whitehouse + * New nbd_end_request() for compatibility with new linux block + * layer code. + * 2003/06/24 Louis D. Langholtz <ldl@aros.net> + * Removed unneeded blksize_bits field from nbd_device struct. + * Cleanup PARANOIA usage & code. + * 2004/02/19 Paul Clements + * Removed PARANOIA, plus various cleanup and comments + */ + +#ifndef LINUX_NBD_H +#define LINUX_NBD_H + +#define NBD_SET_SOCK _IO( 0xab, 0 ) +#define NBD_SET_BLKSIZE _IO( 0xab, 1 ) +#define NBD_SET_SIZE _IO( 0xab, 2 ) +#define NBD_DO_IT _IO( 0xab, 3 ) +#define NBD_CLEAR_SOCK _IO( 0xab, 4 ) +#define NBD_CLEAR_QUE _IO( 0xab, 5 ) +#define NBD_PRINT_DEBUG _IO( 0xab, 6 ) +#define NBD_SET_SIZE_BLOCKS _IO( 0xab, 7 ) +#define NBD_DISCONNECT _IO( 0xab, 8 ) + +enum { + NBD_CMD_READ = 0, + NBD_CMD_WRITE = 1, + NBD_CMD_DISC = 2 +}; + +#define nbd_cmd(req) ((req)->cmd[0]) +#define MAX_NBD 128 + +/* userspace doesn't need the nbd_device structure */ +#ifdef __KERNEL__ + +/* values for flags field */ +#define NBD_READ_ONLY 0x0001 +#define NBD_WRITE_NOCHK 0x0002 + +struct nbd_device { + int flags; + int harderror; /* Code of hard error */ + struct socket * sock; + struct file * file; /* If == NULL, device is not ready, yet */ + int magic; + spinlock_t queue_lock; + struct list_head queue_head;/* Requests are added here... */ + struct semaphore tx_lock; + struct gendisk *disk; + int blksize; + u64 bytesize; +}; + +#endif + +/* These are sent over the network in the request/reply magic fields */ + +#define NBD_REQUEST_MAGIC 0x25609513 +#define NBD_REPLY_MAGIC 0x67446698 +/* Do *not* use magics: 0x12560953 0x96744668. */ + +/* + * This is the packet used for communication between client and + * server. All data are in network byte order. + */ +struct nbd_request { + u32 magic; + u32 type; /* == READ || == WRITE */ + char handle[8]; + u64 from; + u32 len; +} +#ifdef __GNUC__ + __attribute__ ((packed)) +#endif +; + +/* + * This is the reply packet that nbd-server sends back to the client after + * it has completed an I/O request (or an error occurs). + */ +struct nbd_reply { + u32 magic; + u32 error; /* 0 = ok, else error */ + char handle[8]; /* handle you got from request */ +}; +#endif |