include/shm_block.h

   1 /***************************************************************************
   2  * Copyright 1995, Technion, Israel Institute of Technology
   3  * Electrical Eng, Software Lab.
   4  * Author:    Michael Veksler.
   5  ***************************************************************************
   6  * File:      shm_block.ch
   7  * Purpose:   treat a shared memory block.
   8  ***************************************************************************
   9  */
  10 #ifndef __WINE_SHM_BLOCK_H
  11 #define __WINE_SHM_BLOCK_H
  12
  13 #ifdef CONFIG_IPC
  14
  15 #include <sys/shm.h>
  16 #include "wintypes.h"
  17 #define SEGSIZE                 0x10000 /* 64 */
  18 #define SHM_GRANULARITY         SEGSIZE
  19 #define SHM_MINBLOCK            SHM_GRANULARITY
  20 #define SHM_MAXBLOCK            (((int)SHMMAX/(int)SHM_GRANULARITY)*  \
  21                                  SHM_GRANULARITY)
  22 #define PTR2REL(block,ptr) (REL_PTR) ( (char *) (ptr) - (char *) (block) )
  23 #define REL2PTR(block,rel) (void *) ( (char *) (block) + (rel) )
  24
  25 typedef  int REL_PTR;
  26
  27 /* full info for each shm block. */
  28 struct shm_block {
  29         /* private */
  30         int next_shm_id;           /* IPC shm ID (for initial linking) */
  31
  32         /* public (read only) */
  33         int size;                  /* size of the shm block */
  34         int free;                  /* how much of the block is free */
  35         int proc_idx;              /* The index of the owner */
  36
  37         /* public - writable for shm_fragment */
  38         REL_PTR free_list;         /* first item in the free list */
  39 };
  40
  41 /* used for mapping local attachments */
  42 struct local_shm_map {
  43         struct local_shm_map *next;
  44         int shm_id;
  45         int proc_idx;
  46
  47         /* 32 bit pointer to the beginning of the block */
  48         struct shm_block *ptr;
  49 };
  50 extern struct local_shm_map *shm_map;
  51 void shm_setup_block(struct shm_block *block, REL_PTR first, int size);
  52
  53 /* shm_create_block:
  54  *   allocate and setup a new block:
  55  *   first - first non header byte.
  56  *   size  - block size (in bytes).
  57  *   shm_id- IPC shared memory ID.
  58  */
  59 struct shm_block *shm_create_block(REL_PTR first, int size, int *shm_id);
  60
  61 /* shm_locate_block:
  62  *   locate existing block according to shm_id,
  63  *   Attach the block if needed. Assume the shm_id is wine's
  64  *   Set selectors also.
  65  */
  66 struct shm_block *shm_locate_block(int shm_id, struct local_shm_map *map);
  67
  68 /* shm_locate_attached_block:
  69  *   locate existing block according to shm_id,
  70  *   Blocks are never attached.
  71  * if proc_idx is not NULL, it will be set to owner's index.
  72  * map - localy mapped info about block may be NULL;
  73  */
  74 struct shm_block *shm_locate_attached_block(int shm_id,
  75                                             struct local_shm_map *map);
  76
  77 /* shm_attach_block: attach existing shm block, setup selectors
  78  * shm_id - id of the block to attach.
  79  * proc_idx - if not -1, puts this data into local mapping
  80  * map - localy mapped info about this block. (may be NULL)
  81  * NOTE: same block can be attached many times
  82  */
  83 struct shm_block *shm_attach_block(int shm_id, int proc_idx,
  84                                    struct local_shm_map *map);
  85
  86 /* delete chain of shm blocks (pointing to each other */
  87 void shm_delete_chain(int *shmid);
  88
  89 #endif  /* CONFIG_IPC */
  90 #endif  /* __WINE_SHM_BLOCK_H */