drivers/staging/ramster/ramster.h

   1 /*
   2  * ramster.h
   3  *
   4  * Peer-to-peer transcendent memory
   5  *
   6  * Copyright (c) 2009-2012, Dan Magenheimer, Oracle Corp.
   7  */
   8
   9 #ifndef _RAMSTER_H_
  10 #define _RAMSTER_H_
  11
  12 /*
  13  * format of remote pampd:
  14  *   bit 0 == intransit
  15  *   bit 1 == is_remote... if this bit is set, then
  16  *   bit 2-9 == remotenode
  17  *   bit 10-22 == size
  18  *   bit 23-30 == cksum
  19  */
  20 #define FAKE_PAMPD_INTRANSIT_BITS       1
  21 #define FAKE_PAMPD_ISREMOTE_BITS        1
  22 #define FAKE_PAMPD_REMOTENODE_BITS      8
  23 #define FAKE_PAMPD_REMOTESIZE_BITS      13
  24 #define FAKE_PAMPD_CHECKSUM_BITS        8
  25
  26 #define FAKE_PAMPD_INTRANSIT_SHIFT      0
  27 #define FAKE_PAMPD_ISREMOTE_SHIFT       (FAKE_PAMPD_INTRANSIT_SHIFT + \
  28                                          FAKE_PAMPD_INTRANSIT_BITS)
  29 #define FAKE_PAMPD_REMOTENODE_SHIFT     (FAKE_PAMPD_ISREMOTE_SHIFT + \
  30                                          FAKE_PAMPD_ISREMOTE_BITS)
  31 #define FAKE_PAMPD_REMOTESIZE_SHIFT     (FAKE_PAMPD_REMOTENODE_SHIFT + \
  32                                          FAKE_PAMPD_REMOTENODE_BITS)
  33 #define FAKE_PAMPD_CHECKSUM_SHIFT       (FAKE_PAMPD_REMOTESIZE_SHIFT + \
  34                                          FAKE_PAMPD_REMOTESIZE_BITS)
  35
  36 #define FAKE_PAMPD_MASK(x)              ((1UL << (x)) - 1)
  37
  38 static inline void *pampd_make_remote(int remotenode, size_t size,
  39                                         unsigned char cksum)
  40 {
  41         unsigned long fake_pampd = 0;
  42         fake_pampd |= 1UL << FAKE_PAMPD_ISREMOTE_SHIFT;
  43         fake_pampd |= ((unsigned long)remotenode &
  44                         FAKE_PAMPD_MASK(FAKE_PAMPD_REMOTENODE_BITS)) <<
  45                                 FAKE_PAMPD_REMOTENODE_SHIFT;
  46         fake_pampd |= ((unsigned long)size &
  47                         FAKE_PAMPD_MASK(FAKE_PAMPD_REMOTESIZE_BITS)) <<
  48                                 FAKE_PAMPD_REMOTESIZE_SHIFT;
  49         fake_pampd |= ((unsigned long)cksum &
  50                         FAKE_PAMPD_MASK(FAKE_PAMPD_CHECKSUM_BITS)) <<
  51                                 FAKE_PAMPD_CHECKSUM_SHIFT;
  52         return (void *)fake_pampd;
  53 }
  54
  55 static inline unsigned int pampd_remote_node(void *pampd)
  56 {
  57         unsigned long fake_pampd = (unsigned long)pampd;
  58         return (fake_pampd >> FAKE_PAMPD_REMOTENODE_SHIFT) &
  59                 FAKE_PAMPD_MASK(FAKE_PAMPD_REMOTENODE_BITS);
  60 }
  61
  62 static inline unsigned int pampd_remote_size(void *pampd)
  63 {
  64         unsigned long fake_pampd = (unsigned long)pampd;
  65         return (fake_pampd >> FAKE_PAMPD_REMOTESIZE_SHIFT) &
  66                 FAKE_PAMPD_MASK(FAKE_PAMPD_REMOTESIZE_BITS);
  67 }
  68
  69 static inline unsigned char pampd_remote_cksum(void *pampd)
  70 {
  71         unsigned long fake_pampd = (unsigned long)pampd;
  72         return (fake_pampd >> FAKE_PAMPD_CHECKSUM_SHIFT) &
  73                 FAKE_PAMPD_MASK(FAKE_PAMPD_CHECKSUM_BITS);
  74 }
  75
  76 static inline bool pampd_is_remote(void *pampd)
  77 {
  78         unsigned long fake_pampd = (unsigned long)pampd;
  79         return (fake_pampd >> FAKE_PAMPD_ISREMOTE_SHIFT) &
  80                 FAKE_PAMPD_MASK(FAKE_PAMPD_ISREMOTE_BITS);
  81 }
  82
  83 static inline bool pampd_is_intransit(void *pampd)
  84 {
  85         unsigned long fake_pampd = (unsigned long)pampd;
  86         return (fake_pampd >> FAKE_PAMPD_INTRANSIT_SHIFT) &
  87                 FAKE_PAMPD_MASK(FAKE_PAMPD_INTRANSIT_BITS);
  88 }
  89
  90 /* note that it is a BUG for intransit to be set without isremote also set */
  91 static inline void *pampd_mark_intransit(void *pampd)
  92 {
  93         unsigned long fake_pampd = (unsigned long)pampd;
  94
  95         fake_pampd |= 1UL << FAKE_PAMPD_ISREMOTE_SHIFT;
  96         fake_pampd |= 1UL << FAKE_PAMPD_INTRANSIT_SHIFT;
  97         return (void *)fake_pampd;
  98 }
  99
 100 static inline void *pampd_mask_intransit_and_remote(void *marked_pampd)
 101 {
 102         unsigned long pampd = (unsigned long)marked_pampd;
 103
 104         pampd &= ~(1UL << FAKE_PAMPD_INTRANSIT_SHIFT);
 105         pampd &= ~(1UL << FAKE_PAMPD_ISREMOTE_SHIFT);
 106         return (void *)pampd;
 107 }
 108
 109 extern int ramster_remote_async_get(struct tmem_xhandle *,
 110                                 bool, int, size_t, uint8_t, void *extra);
 111 extern int ramster_remote_put(struct tmem_xhandle *, char *, size_t,
 112                                 bool, int *);
 113 extern int ramster_remote_flush(struct tmem_xhandle *, int);
 114 extern int ramster_remote_flush_object(struct tmem_xhandle *, int);
 115 extern int r2net_register_handlers(void);
 116 extern int r2net_remote_target_node_set(int);
 117
 118 #endif /* _TMEM_H */