freebsd-nq/sys/vm/vm_map.h
Matthew Dillon b823bbd6be Fix a lock reversal problem in the VM subsystem related to threaded
programs.   There is a case during a fork() which can cause a deadlock.

From Tor -
The workaround that consists of setting a flag in the vm map that
indicates that a fork is in progress and using that mark in the page
fault handling to force a revalidation failure.  That change will only
affect (pessimize) page fault handling during fork for threaded
(linuxthreads style) applications and applications using aio_*().

Submited by: tegge
2001-03-14 06:48:53 +00:00

383 lines
14 KiB
C

/*
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* The Mach Operating System project at Carnegie-Mellon University.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)vm_map.h 8.9 (Berkeley) 5/17/95
*
*
* Copyright (c) 1987, 1990 Carnegie-Mellon University.
* All rights reserved.
*
* Authors: Avadis Tevanian, Jr., Michael Wayne Young
*
* 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 the
* rights to redistribute these changes.
*
* $FreeBSD$
*/
/*
* Virtual memory map module definitions.
*/
#ifndef _VM_MAP_
#define _VM_MAP_
/*
* Types defined:
*
* vm_map_t the high-level address map data structure.
* vm_map_entry_t an entry in an address map.
*/
typedef u_int vm_eflags_t;
/*
* Objects which live in maps may be either VM objects, or
* another map (called a "sharing map") which denotes read-write
* sharing with other maps.
*/
union vm_map_object {
struct vm_object *vm_object; /* object object */
struct vm_map *sub_map; /* belongs to another map */
};
/*
* Address map entries consist of start and end addresses,
* a VM object (or sharing map) and offset into that object,
* and user-exported inheritance and protection information.
* Also included is control information for virtual copy operations.
*/
struct vm_map_entry {
struct vm_map_entry *prev; /* previous entry */
struct vm_map_entry *next; /* next entry */
vm_offset_t start; /* start address */
vm_offset_t end; /* end address */
vm_offset_t avail_ssize; /* amt can grow if this is a stack */
union vm_map_object object; /* object I point to */
vm_ooffset_t offset; /* offset into object */
vm_eflags_t eflags; /* map entry flags */
/* Only in task maps: */
vm_prot_t protection; /* protection code */
vm_prot_t max_protection; /* maximum protection */
vm_inherit_t inheritance; /* inheritance */
int wired_count; /* can be paged if = 0 */
vm_pindex_t lastr; /* last read */
};
#define MAP_ENTRY_NOSYNC 0x0001
#define MAP_ENTRY_IS_SUB_MAP 0x0002
#define MAP_ENTRY_COW 0x0004
#define MAP_ENTRY_NEEDS_COPY 0x0008
#define MAP_ENTRY_NOFAULT 0x0010
#define MAP_ENTRY_USER_WIRED 0x0020
#define MAP_ENTRY_BEHAV_NORMAL 0x0000 /* default behavior */
#define MAP_ENTRY_BEHAV_SEQUENTIAL 0x0040 /* expect sequential access */
#define MAP_ENTRY_BEHAV_RANDOM 0x0080 /* expect random access */
#define MAP_ENTRY_BEHAV_RESERVED 0x00C0 /* future use */
#define MAP_ENTRY_BEHAV_MASK 0x00C0
#define MAP_ENTRY_NOCOREDUMP 0x0400 /* don't include in a core */
static __inline u_char
vm_map_entry_behavior(struct vm_map_entry *entry)
{
return entry->eflags & MAP_ENTRY_BEHAV_MASK;
}
static __inline void
vm_map_entry_set_behavior(struct vm_map_entry *entry, u_char behavior)
{
entry->eflags = (entry->eflags & ~MAP_ENTRY_BEHAV_MASK) |
(behavior & MAP_ENTRY_BEHAV_MASK);
}
/*
* Maps are doubly-linked lists of map entries, kept sorted
* by address. A single hint is provided to start
* searches again from the last successful search,
* insertion, or removal.
*
* Note: the lock structure cannot be the first element of vm_map
* because this can result in a running lockup between two or more
* system processes trying to kmem_alloc_wait() due to kmem_alloc_wait()
* and free tsleep/waking up 'map' and the underlying lockmgr also
* sleeping and waking up on 'map'. The lockup occurs when the map fills
* up. The 'exec' map, for example.
*/
struct vm_map {
struct vm_map_entry header; /* List of entries */
struct lock lock; /* Lock for map data */
int nentries; /* Number of entries */
vm_size_t size; /* virtual size */
u_char system_map; /* Am I a system map? */
u_char infork; /* Am I in fork processing? */
vm_map_entry_t hint; /* hint for quick lookups */
unsigned int timestamp; /* Version number */
vm_map_entry_t first_free; /* First free space hint */
struct pmap *pmap; /* Physical map */
#define min_offset header.start
#define max_offset header.end
};
/*
* Shareable process virtual address space.
* May eventually be merged with vm_map.
* Several fields are temporary (text, data stuff).
*/
struct vmspace {
struct vm_map vm_map; /* VM address map */
struct pmap vm_pmap; /* private physical map */
int vm_refcnt; /* number of references */
caddr_t vm_shm; /* SYS5 shared memory private data XXX */
/* we copy from vm_startcopy to the end of the structure on fork */
#define vm_startcopy vm_rssize
segsz_t vm_rssize; /* current resident set size in pages */
segsz_t vm_swrss; /* resident set size before last swap */
segsz_t vm_tsize; /* text size (pages) XXX */
segsz_t vm_dsize; /* data size (pages) XXX */
segsz_t vm_ssize; /* stack size (pages) */
caddr_t vm_taddr; /* user virtual address of text XXX */
caddr_t vm_daddr; /* user virtual address of data XXX */
caddr_t vm_maxsaddr; /* user VA at max stack growth */
caddr_t vm_minsaddr; /* user VA at max stack growth */
};
/*
* Macros: vm_map_lock, etc.
* Function:
* Perform locking on the data portion of a map. Note that
* these macros mimic procedure calls returning void. The
* semicolon is supplied by the user of these macros, not
* by the macros themselves. The macros can safely be used
* as unbraced elements in a higher level statement.
*/
/* XXX This macro is not called anywhere, and (map)->ref_lock doesn't exist. */
#define vm_map_lock_drain_interlock(map) \
do { \
lockmgr(&(map)->lock, LK_DRAIN|LK_INTERLOCK, \
&(map)->ref_lock, curproc); \
(map)->timestamp++; \
} while(0)
#ifdef DIAGNOSTIC
/* #define MAP_LOCK_DIAGNOSTIC 1 */
#ifdef MAP_LOCK_DIAGNOSTIC
#define vm_map_lock(map) \
do { \
printf ("locking map LK_EXCLUSIVE: 0x%x\n", map); \
if (lockmgr(&(map)->lock, LK_EXCLUSIVE, (void *)0, curproc) != 0) { \
panic("vm_map_lock: failed to get lock"); \
} \
(map)->timestamp++; \
} while(0)
#else
#define vm_map_lock(map) \
do { \
if (lockmgr(&(map)->lock, LK_EXCLUSIVE, (void *)0, curproc) != 0) { \
panic("vm_map_lock: failed to get lock"); \
} \
(map)->timestamp++; \
} while(0)
#endif
#else
#define vm_map_lock(map) \
do { \
lockmgr(&(map)->lock, LK_EXCLUSIVE, (void *)0, curproc); \
(map)->timestamp++; \
} while(0)
#endif /* DIAGNOSTIC */
#if defined(MAP_LOCK_DIAGNOSTIC)
#define vm_map_unlock(map) \
do { \
printf ("locking map LK_RELEASE: 0x%x\n", map); \
lockmgr(&(map)->lock, LK_RELEASE, (void *)0, curproc); \
} while (0)
#define vm_map_lock_read(map) \
do { \
printf ("locking map LK_SHARED: 0x%x\n", map); \
lockmgr(&(map)->lock, LK_SHARED, (void *)0, curproc); \
} while (0)
#define vm_map_unlock_read(map) \
do { \
printf ("locking map LK_RELEASE: 0x%x\n", map); \
lockmgr(&(map)->lock, LK_RELEASE, (void *)0, curproc); \
} while (0)
#else
#define vm_map_unlock(map) \
lockmgr(&(map)->lock, LK_RELEASE, (void *)0, curproc)
#define vm_map_lock_read(map) \
lockmgr(&(map)->lock, LK_SHARED, (void *)0, curproc)
#define vm_map_unlock_read(map) \
lockmgr(&(map)->lock, LK_RELEASE, (void *)0, curproc)
#endif
static __inline__ int
_vm_map_lock_upgrade(vm_map_t map, struct proc *p) {
int error;
#if defined(MAP_LOCK_DIAGNOSTIC)
printf("locking map LK_EXCLUPGRADE: 0x%x\n", map);
#endif
error = lockmgr(&map->lock, LK_EXCLUPGRADE, (void *)0, p);
if (error == 0)
map->timestamp++;
return error;
}
#define vm_map_lock_upgrade(map) _vm_map_lock_upgrade(map, curproc)
#if defined(MAP_LOCK_DIAGNOSTIC)
#define vm_map_lock_downgrade(map) \
do { \
printf ("locking map LK_DOWNGRADE: 0x%x\n", map); \
lockmgr(&(map)->lock, LK_DOWNGRADE, (void *)0, curproc); \
} while (0)
#else
#define vm_map_lock_downgrade(map) \
lockmgr(&(map)->lock, LK_DOWNGRADE, (void *)0, curproc)
#endif
#define vm_map_set_recursive(map) \
do { \
mtx_lock((map)->lock.lk_interlock); \
(map)->lock.lk_flags |= LK_CANRECURSE; \
mtx_unlock((map)->lock.lk_interlock); \
} while(0)
#define vm_map_clear_recursive(map) \
do { \
mtx_lock((map)->lock.lk_interlock); \
(map)->lock.lk_flags &= ~LK_CANRECURSE; \
mtx_unlock((map)->lock.lk_interlock); \
} while(0)
/*
* Functions implemented as macros
*/
#define vm_map_min(map) ((map)->min_offset)
#define vm_map_max(map) ((map)->max_offset)
#define vm_map_pmap(map) ((map)->pmap)
static __inline struct pmap *
vmspace_pmap(struct vmspace *vmspace)
{
return &vmspace->vm_pmap;
}
static __inline long
vmspace_resident_count(struct vmspace *vmspace)
{
return pmap_resident_count(vmspace_pmap(vmspace));
}
/* XXX: number of kernel maps and entries to statically allocate */
#define MAX_KMAP 10
#define MAX_KMAPENT 128
#define MAX_MAPENT 128
/*
* Copy-on-write flags for vm_map operations
*/
#define MAP_UNUSED_01 0x0001
#define MAP_COPY_ON_WRITE 0x0002
#define MAP_NOFAULT 0x0004
#define MAP_PREFAULT 0x0008
#define MAP_PREFAULT_PARTIAL 0x0010
#define MAP_DISABLE_SYNCER 0x0020
#define MAP_DISABLE_COREDUMP 0x0100
/*
* vm_fault option flags
*/
#define VM_FAULT_NORMAL 0 /* Nothing special */
#define VM_FAULT_CHANGE_WIRING 1 /* Change the wiring as appropriate */
#define VM_FAULT_USER_WIRE 2 /* Likewise, but for user purposes */
#define VM_FAULT_WIRE_MASK (VM_FAULT_CHANGE_WIRING|VM_FAULT_USER_WIRE)
#define VM_FAULT_HOLD 4 /* Hold the page */
#define VM_FAULT_DIRTY 8 /* Dirty the page */
#ifdef _KERNEL
boolean_t vm_map_check_protection __P((vm_map_t, vm_offset_t, vm_offset_t, vm_prot_t));
struct pmap;
vm_map_t vm_map_create __P((struct pmap *, vm_offset_t, vm_offset_t));
int vm_map_delete __P((vm_map_t, vm_offset_t, vm_offset_t));
int vm_map_find __P((vm_map_t, vm_object_t, vm_ooffset_t, vm_offset_t *, vm_size_t, boolean_t, vm_prot_t, vm_prot_t, int));
int vm_map_findspace __P((vm_map_t, vm_offset_t, vm_size_t, vm_offset_t *));
int vm_map_inherit __P((vm_map_t, vm_offset_t, vm_offset_t, vm_inherit_t));
void vm_map_init __P((struct vm_map *, vm_offset_t, vm_offset_t));
void vm_map_destroy __P((struct vm_map *));
int vm_map_insert __P((vm_map_t, vm_object_t, vm_ooffset_t, vm_offset_t, vm_offset_t, vm_prot_t, vm_prot_t, int));
int vm_map_lookup __P((vm_map_t *, vm_offset_t, vm_prot_t, vm_map_entry_t *, vm_object_t *,
vm_pindex_t *, vm_prot_t *, boolean_t *));
void vm_map_lookup_done __P((vm_map_t, vm_map_entry_t));
boolean_t vm_map_lookup_entry __P((vm_map_t, vm_offset_t, vm_map_entry_t *));
int vm_map_pageable __P((vm_map_t, vm_offset_t, vm_offset_t, boolean_t));
int vm_map_user_pageable __P((vm_map_t, vm_offset_t, vm_offset_t, boolean_t));
int vm_map_clean __P((vm_map_t, vm_offset_t, vm_offset_t, boolean_t, boolean_t));
int vm_map_protect __P((vm_map_t, vm_offset_t, vm_offset_t, vm_prot_t, boolean_t));
int vm_map_remove __P((vm_map_t, vm_offset_t, vm_offset_t));
void vm_map_startup __P((void));
int vm_map_submap __P((vm_map_t, vm_offset_t, vm_offset_t, vm_map_t));
int vm_map_madvise __P((vm_map_t, vm_offset_t, vm_offset_t, int));
void vm_map_simplify_entry __P((vm_map_t, vm_map_entry_t));
void vm_init2 __P((void));
int vm_uiomove __P((vm_map_t, vm_object_t, off_t, int, vm_offset_t, int *));
void vm_freeze_copyopts __P((vm_object_t, vm_pindex_t, vm_pindex_t));
int vm_map_stack __P((vm_map_t, vm_offset_t, vm_size_t, vm_prot_t, vm_prot_t, int));
int vm_map_growstack __P((struct proc *p, vm_offset_t addr));
#endif
#endif /* _VM_MAP_ */