lustre/portals/include/linux/kpr.h

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  */
   4 #ifndef _KPR_H
   5 #define _KPR_H
   6
   7 # include <portals/lib-types.h> /* for ptl_hdr_t */
   8
   9 /******************************************************************************/
  10 /* Kernel Portals Router interface */
  11
  12 typedef void (*kpr_fwd_callback_t)(void *arg, int error); // completion callback
  13
  14 /* space for routing targets to stash "stuff" in a forwarded packet */
  15 typedef union {
  16         long long        _alignment;
  17         void            *_space[16];            /* scale with CPU arch */
  18 } kprfd_scratch_t;
  19
  20 /* Kernel Portals Routing Forwarded message Descriptor */
  21 typedef struct {
  22         struct list_head     kprfd_list;        /* stash in queues (routing target can use) */
  23         ptl_nid_t            kprfd_target_nid;  /* final destination NID */
  24         ptl_nid_t            kprfd_gateway_nid; /* gateway NID */
  25         ptl_hdr_t           *kprfd_hdr;         /* header in wire byte order */
  26         int                  kprfd_nob;         /* # payload bytes */
  27         int                  kprfd_niov;        /* # payload frags */
  28         ptl_kiov_t          *kprfd_kiov;        /* payload fragments */
  29         void                *kprfd_router_arg;  /* originating NAL's router arg */
  30         kpr_fwd_callback_t   kprfd_callback;    /* completion callback */
  31         void                *kprfd_callback_arg; /* completion callback arg */
  32         kprfd_scratch_t      kprfd_scratch;     /* scratchpad for routing targets */
  33 } kpr_fwd_desc_t;
  34
  35 typedef void  (*kpr_fwd_t)(void *arg, kpr_fwd_desc_t *fwd);
  36 typedef void  (*kpr_notify_t)(void *arg, ptl_nid_t peer, int alive);
  37
  38 /* NAL's routing interface (Kernel Portals Routing Nal Interface) */
  39 typedef const struct {
  40         int             kprni_nalid;    /* NAL's id */
  41         void           *kprni_arg;      /* Arg to pass when calling into NAL */
  42         kpr_fwd_t       kprni_fwd;      /* NAL's forwarding entrypoint */
  43         kpr_notify_t    kprni_notify;   /* NAL's notification entrypoint */
  44 } kpr_nal_interface_t;
  45
  46 /* Router's routing interface (Kernel Portals Routing Router Interface) */
  47 typedef const struct {
  48         /* register the calling NAL with the router and get back the handle for
  49          * subsequent calls */
  50         int     (*kprri_register) (kpr_nal_interface_t *nal_interface,
  51                                    void **router_arg);
  52
  53         /* ask the router to find a gateway that forwards to 'nid' and is a
  54          * peer of the calling NAL; assume caller will send 'nob' bytes of
  55          * payload there */
  56         int     (*kprri_lookup) (void *router_arg, ptl_nid_t nid, int nob,
  57                                  ptl_nid_t *gateway_nid);
  58
  59         /* hand a packet over to the router for forwarding */
  60         kpr_fwd_t kprri_fwd_start;
  61
  62         /* hand a packet back to the router for completion */
  63         void    (*kprri_fwd_done) (void *router_arg, kpr_fwd_desc_t *fwd,
  64                                    int error);
  65
  66         /* notify the router about peer state */
  67         void    (*kprri_notify) (void *router_arg, ptl_nid_t peer,
  68                                  int alive, time_t when);
  69
  70         /* the calling NAL is shutting down */
  71         void    (*kprri_shutdown) (void *router_arg);
  72
  73         /* deregister the calling NAL with the router */
  74         void    (*kprri_deregister) (void *router_arg);
  75
  76 } kpr_router_interface_t;
  77
  78 /* Convenient struct for NAL to stash router interface/args */
  79 typedef struct {
  80         kpr_router_interface_t  *kpr_interface;
  81         void                    *kpr_arg;
  82 } kpr_router_t;
  83
  84 extern kpr_router_interface_t   kpr_router_interface;
  85
  86 static inline int
  87 kpr_register (kpr_router_t *router, kpr_nal_interface_t *nalif)
  88 {
  89         int    rc;
  90
  91         router->kpr_interface = PORTAL_SYMBOL_GET (kpr_router_interface);
  92         if (router->kpr_interface == NULL)
  93                 return (-ENOENT);
  94
  95         rc = (router->kpr_interface)->kprri_register (nalif, &router->kpr_arg);
  96         if (rc != 0)
  97                 router->kpr_interface = NULL;
  98
  99         PORTAL_SYMBOL_PUT (kpr_router_interface);
 100         return (rc);
 101 }
 102
 103 static inline int
 104 kpr_routing (kpr_router_t *router)
 105 {
 106         return (router->kpr_interface != NULL);
 107 }
 108
 109 static inline int
 110 kpr_lookup (kpr_router_t *router, ptl_nid_t nid, int nob, ptl_nid_t *gateway_nid)
 111 {
 112         if (!kpr_routing (router))
 113                 return (-ENETUNREACH);
 114
 115         return (router->kpr_interface->kprri_lookup(router->kpr_arg, nid, nob,
 116                                                     gateway_nid));
 117 }
 118
 119 static inline void
 120 kpr_fwd_init (kpr_fwd_desc_t *fwd, ptl_nid_t nid, ptl_hdr_t *hdr,
 121               int nob, int niov, ptl_kiov_t *kiov,
 122               kpr_fwd_callback_t callback, void *callback_arg)
 123 {
 124         fwd->kprfd_target_nid   = nid;
 125         fwd->kprfd_gateway_nid  = nid;
 126         fwd->kprfd_hdr          = hdr;
 127         fwd->kprfd_nob          = nob;
 128         fwd->kprfd_niov         = niov;
 129         fwd->kprfd_kiov         = kiov;
 130         fwd->kprfd_callback     = callback;
 131         fwd->kprfd_callback_arg = callback_arg;
 132 }
 133
 134 static inline void
 135 kpr_fwd_start (kpr_router_t *router, kpr_fwd_desc_t *fwd)
 136 {
 137         if (!kpr_routing (router))
 138                 fwd->kprfd_callback (fwd->kprfd_callback_arg, -ENETUNREACH);
 139         else
 140                 router->kpr_interface->kprri_fwd_start (router->kpr_arg, fwd);
 141 }
 142
 143 static inline void
 144 kpr_fwd_done (kpr_router_t *router, kpr_fwd_desc_t *fwd, int error)
 145 {
 146         LASSERT (kpr_routing (router));
 147         router->kpr_interface->kprri_fwd_done (router->kpr_arg, fwd, error);
 148 }
 149
 150 static inline void
 151 kpr_notify (kpr_router_t *router,
 152             ptl_nid_t peer, int alive, time_t when)
 153 {
 154         if (!kpr_routing (router))
 155                 return;
 156
 157         router->kpr_interface->kprri_notify(router->kpr_arg, peer, alive, when);
 158 }
 159
 160 static inline void
 161 kpr_shutdown (kpr_router_t *router)
 162 {
 163         if (kpr_routing (router))
 164                 router->kpr_interface->kprri_shutdown (router->kpr_arg);
 165 }
 166
 167 static inline void
 168 kpr_deregister (kpr_router_t *router)
 169 {
 170         if (!kpr_routing (router))
 171                 return;
 172         router->kpr_interface->kprri_deregister (router->kpr_arg);
 173         router->kpr_interface = NULL;
 174 }
 175
 176 #endif /* _KPR_H */