include/linux/nbd.h

   1 #ifndef LINUX_NBD_H
   2 #define LINUX_NBD_H
   3
   4 #define NBD_SET_SOCK    _IO( 0xab, 0 )
   5 #define NBD_SET_BLKSIZE _IO( 0xab, 1 )
   6 #define NBD_SET_SIZE    _IO( 0xab, 2 )
   7 #define NBD_DO_IT       _IO( 0xab, 3 )
   8 #define NBD_CLEAR_SOCK  _IO( 0xab, 4 )
   9 #define NBD_CLEAR_QUE   _IO( 0xab, 5 )
  10 #define NBD_PRINT_DEBUG _IO( 0xab, 6 )
  11 #define NBD_SET_SIZE_BLOCKS     _IO( 0xab, 7 )
  12
  13 #ifdef MAJOR_NR
  14
  15 #include <linux/locks.h>
  16 #include <asm/semaphore.h>
  17
  18 #define LOCAL_END_REQUEST
  19
  20 #include <linux/blk.h>
  21
  22 #ifdef PARANOIA
  23 extern int requests_in;
  24 extern int requests_out;
  25 #endif
  26
  27 static void
  28 nbd_end_request(struct request *req)
  29 {
  30 #ifdef PARANOIA
  31         requests_out++;
  32 #endif
  33         if (end_that_request_first( req, !req->errors, "nbd" ))
  34                 return;
  35         end_that_request_last( req );
  36 }
  37
  38 #define MAX_NBD 128
  39
  40 struct nbd_device {
  41         int refcnt;
  42         int flags;
  43         int harderror;          /* Code of hard error                   */
  44 #define NBD_READ_ONLY 0x0001
  45 #define NBD_WRITE_NOCHK 0x0002
  46 #define NBD_INITIALISED 0x0004
  47         struct socket * sock;
  48         struct file * file;             /* If == NULL, device is not ready, yet */
  49         int magic;                      /* FIXME: not if debugging is off       */
  50         struct request *head;   /* Requests are added here...                   */
  51         struct request *tail;
  52         struct semaphore queue_lock;
  53 };
  54 #endif
  55
  56 /* This now IS in some kind of include file...  */
  57
  58 /* These are send over network in request/reply magic field */
  59
  60 #define NBD_REQUEST_MAGIC 0x25609513
  61 #define NBD_REPLY_MAGIC 0x67446698
  62 /* Do *not* use magics: 0x12560953 0x96744668. */
  63
  64 /*
  65  * This is packet used for communication between client and
  66  * server. All data are in network byte order.
  67  */
  68 struct nbd_request {
  69         u32 magic;
  70         u32 type;       /* == READ || == WRITE  */
  71         char handle[8];
  72         u64 from;
  73         u32 len;
  74 }
  75 #ifdef __GNUC__
  76         __attribute__ ((packed))
  77 #endif
  78 ;
  79
  80 struct nbd_reply {
  81         u32 magic;
  82         u32 error;              /* 0 = ok, else error   */
  83         char handle[8];         /* handle you got from request  */
  84 };
  85 #endif