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dsm.h
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1/*-------------------------------------------------------------------------
2 *
3 * dsm.h
4 * manage dynamic shared memory segments
5 *
6 * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
7 * Portions Copyright (c) 1994, Regents of the University of California
8 *
9 * src/include/storage/dsm.h
10 *
11 *-------------------------------------------------------------------------
12 */
13#ifndef DSM_H
14#define DSM_H
15
16#include "storage/dsm_impl.h"
17
18typedef struct dsm_segment dsm_segment;
19
20#define DSM_CREATE_NULL_IF_MAXSEGMENTS 0x0001
21
22/* Startup and shutdown functions. */
23struct PGShmemHeader; /* avoid including pg_shmem.h */
24extern void dsm_cleanup_using_control_segment(dsm_handle old_control_handle);
25extern void dsm_postmaster_startup(struct PGShmemHeader *);
26extern void dsm_backend_shutdown(void);
27extern void dsm_detach_all(void);
28
29extern size_t dsm_estimate_size(void);
30extern void dsm_shmem_init(void);
31
32#ifdef EXEC_BACKEND
33extern void dsm_set_control_handle(dsm_handle h);
34#endif
35
36/* Functions that create or remove mappings. */
37extern dsm_segment *dsm_create(Size size, int flags);
39extern void dsm_detach(dsm_segment *seg);
40
41/* Resource management functions. */
42extern void dsm_pin_mapping(dsm_segment *seg);
43extern void dsm_unpin_mapping(dsm_segment *seg);
44extern void dsm_pin_segment(dsm_segment *seg);
45extern void dsm_unpin_segment(dsm_handle handle);
47
48/* Informational functions. */
49extern void *dsm_segment_address(dsm_segment *seg);
52
53/* Cleanup hooks. */
55extern void on_dsm_detach(dsm_segment *seg,
57extern void cancel_on_dsm_detach(dsm_segment *seg,
59extern void reset_on_dsm_detach(void);
60
61#endif /* DSM_H */
size_t Size
Definition: c.h:562
dsm_handle dsm_segment_handle(dsm_segment *seg)
Definition: dsm.c:1123
size_t dsm_estimate_size(void)
Definition: dsm.c:470
void dsm_detach(dsm_segment *seg)
Definition: dsm.c:803
void on_dsm_detach(dsm_segment *seg, on_dsm_detach_callback function, Datum arg)
Definition: dsm.c:1132
void dsm_pin_mapping(dsm_segment *seg)
Definition: dsm.c:915
void dsm_postmaster_startup(struct PGShmemHeader *)
Definition: dsm.c:177
void dsm_unpin_segment(dsm_handle handle)
Definition: dsm.c:988
void dsm_pin_segment(dsm_segment *seg)
Definition: dsm.c:955
void dsm_detach_all(void)
Definition: dsm.c:775
void * dsm_segment_address(dsm_segment *seg)
Definition: dsm.c:1095
void dsm_cleanup_using_control_segment(dsm_handle old_control_handle)
Definition: dsm.c:238
dsm_segment * dsm_create(Size size, int flags)
Definition: dsm.c:516
void(* on_dsm_detach_callback)(dsm_segment *, Datum arg)
Definition: dsm.h:54
dsm_segment * dsm_attach(dsm_handle h)
Definition: dsm.c:665
void dsm_shmem_init(void)
Definition: dsm.c:479
void dsm_backend_shutdown(void)
Definition: dsm.c:757
dsm_segment * dsm_find_mapping(dsm_handle handle)
Definition: dsm.c:1076
void cancel_on_dsm_detach(dsm_segment *seg, on_dsm_detach_callback function, Datum arg)
Definition: dsm.c:1147
void reset_on_dsm_detach(void)
Definition: dsm.c:1170
Size dsm_segment_map_length(dsm_segment *seg)
Definition: dsm.c:1105
void dsm_unpin_mapping(dsm_segment *seg)
Definition: dsm.c:934
uint32 dsm_handle
Definition: dsm_impl.h:55
on_exit_nicely_callback function
void * arg
uintptr_t Datum
Definition: postgres.h:69
static pg_noinline void Size size
Definition: slab.c:607