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Diffstat (limited to 'ipc/ipc_table.h')
| -rw-r--r-- | ipc/ipc_table.h | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/ipc/ipc_table.h b/ipc/ipc_table.h new file mode 100644 index 0000000..3bfcc46 --- /dev/null +++ b/ipc/ipc_table.h @@ -0,0 +1,138 @@ +/* + * Mach Operating System + * Copyright (c) 1991,1990,1989 Carnegie Mellon University + * All Rights Reserved. + * + * Permission to use, copy, modify and distribute this software and its + * documentation is hereby granted, provided that both the copyright + * notice and this permission notice appear in all copies of the + * software, derivative works or modified versions, and any portions + * thereof, and that both notices appear in supporting documentation. + * + * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" + * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR + * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. + * + * Carnegie Mellon requests users of this software to return to + * + * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU + * School of Computer Science + * Carnegie Mellon University + * Pittsburgh PA 15213-3890 + * + * any improvements or extensions that they make and grant Carnegie Mellon + * the rights to redistribute these changes. + */ +/* + */ +/* + * File: ipc/ipc_table.h + * Author: Rich Draves + * Date: 1989 + * + * Definitions for tables, used for IPC capabilities (ipc_entry_t) + * and dead-name requests (ipc_port_request_t). + */ + +#ifndef _IPC_IPC_TABLE_H_ +#define _IPC_IPC_TABLE_H_ + +#include <mach/boolean.h> +#include <mach/vm_param.h> + +/* + * The is_table_next field of an ipc_space_t points to + * an ipc_table_size structure. These structures must + * be elements of an array, ipc_table_entries. + * + * The array must end with two elements with the same its_size value. + * Except for the terminating element, the its_size values must + * be strictly increasing. The largest (last) its_size value + * must be less than or equal to MACH_PORT_INDEX(MACH_PORT_DEAD). + * This ensures that + * 1) MACH_PORT_INDEX(MACH_PORT_DEAD) isn't a valid index + * in the table, so ipc_entry_get won't allocate it. + * 2) MACH_PORT_MAKE(index+1, 0) and MAKE_PORT_MAKE(size, 0) + * won't ever overflow. + * + * + * The ipr_size field of the first element in a table of + * dead-name requests (ipc_port_request_t) points to the + * ipc_table_size structure. The structures must be elements + * of ipc_table_dnrequests. ipc_table_dnrequests must end + * with an element with zero its_size, and except for this last + * element, the its_size values must be strictly increasing. + * + * The is_table_next field points to the ipc_table_size structure + * for the next larger size of table, not the one currently in use. + * The ipr_size field points to the currently used ipc_table_size. + */ + +typedef unsigned int ipc_table_index_t; /* index into tables */ +typedef unsigned int ipc_table_elems_t; /* size of tables */ + +typedef struct ipc_table_size { + ipc_table_elems_t its_size; /* number of elements in table */ +} *ipc_table_size_t; + +#define ITS_NULL ((ipc_table_size_t) 0) + +extern ipc_table_size_t ipc_table_entries; +extern ipc_table_size_t ipc_table_dnrequests; + +extern void +ipc_table_init(); + +/* + * Note that ipc_table_alloc, ipc_table_realloc, and ipc_table_free + * all potentially use the VM system. Hence simple locks can't + * be held across them. + * + * We can't use a copying realloc, because the realloc happens + * with the data unlocked. ipc_table_realloc remaps the data, + * so it is OK. + */ + +/* Allocate a table */ +extern vm_offset_t ipc_table_alloc( + vm_size_t size); + +/* Reallocate a big table */ +extern vm_offset_t ipc_table_realloc( + vm_size_t old_size, + vm_offset_t old_table, + vm_size_t new_size); + +/* Free a table */ +extern void ipc_table_free( + vm_size_t size, + vm_offset_t table); + +#define it_entries_alloc(its) \ + ((ipc_entry_t) \ + ipc_table_alloc((its)->its_size * sizeof(struct ipc_entry))) + +#define it_entries_reallocable(its) \ + (((its)->its_size * sizeof(struct ipc_entry)) >= PAGE_SIZE) + +#define it_entries_realloc(its, table, nits) \ + ((ipc_entry_t) \ + ipc_table_realloc((its)->its_size * sizeof(struct ipc_entry), \ + (vm_offset_t)(table), \ + (nits)->its_size * sizeof(struct ipc_entry))) + +#define it_entries_free(its, table) \ + ipc_table_free((its)->its_size * sizeof(struct ipc_entry), \ + (vm_offset_t)(table)) + +#define it_dnrequests_alloc(its) \ + ((ipc_port_request_t) \ + ipc_table_alloc((its)->its_size * \ + sizeof(struct ipc_port_request))) + +#define it_dnrequests_free(its, table) \ + ipc_table_free((its)->its_size * \ + sizeof(struct ipc_port_request), \ + (vm_offset_t)(table)) + +#endif /* _IPC_IPC_TABLE_H_ */ |