/* $NetBSD: uvm_map.h,v 1.80 2020/05/26 00:50:53 kamil Exp $ */
/*
* Copyright (c) 1997 Charles D. Cranor and Washington University.
* 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. 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 8.3 (Berkeley) 3/15/94
* from: Id: uvm_map.h,v 1.1.2.3 1998/02/07 01:16:55 chs Exp
*
*
* Copyright (c) 1987, 1990 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
[email protected]
* 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.
*/
#ifndef _UVM_UVM_MAP_H_
#define _UVM_UVM_MAP_H_
/*
* uvm_map.h
*/
#ifdef _KERNEL
/*
* macros
*/
/*
* UVM_MAP_CLIP_START: ensure that the entry begins at or after
* the starting address, if it doesn't we split the entry.
*
* => map must be locked by caller
*/
#define UVM_MAP_CLIP_START(MAP,ENTRY,VA) { \
if ((VA) > (ENTRY)->start && (VA) < (ENTRY)->end) { \
uvm_map_clip_start(MAP,ENTRY,VA); \
} \
}
/*
* UVM_MAP_CLIP_END: ensure that the entry ends at or before
* the ending address, if it does't we split the entry.
*
* => map must be locked by caller
*/
#define UVM_MAP_CLIP_END(MAP,ENTRY,VA) { \
if ((VA) > (ENTRY)->start && (VA) < (ENTRY)->end) { \
uvm_map_clip_end(MAP,ENTRY,VA); \
} \
}
/*
* extract flags
*/
#define UVM_EXTRACT_REMOVE 0x01 /* remove mapping from old map */
#define UVM_EXTRACT_CONTIG 0x02 /* try to keep it contig */
#define UVM_EXTRACT_QREF 0x04 /* use quick refs */
#define UVM_EXTRACT_FIXPROT 0x08 /* set prot to maxprot as we go */
#define UVM_EXTRACT_RESERVED 0x10 /* caller did uvm_map_reserve() */
#define UVM_EXTRACT_PROT_ALL 0x20 /* set prot to UVM_PROT_ALL */
#endif /* _KERNEL */
#include <sys/rbtree.h>
#include <sys/pool.h>
#include <sys/rwlock.h>
#include <sys/mutex.h>
#include <sys/condvar.h>
#include <uvm/uvm_anon.h>
/*
* 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.
*
* At runtime this is aligned on a cacheline boundary, with fields
* used during fault processing to do RB tree lookup clustered at
* the beginning.
*/
struct vm_map_entry {
struct rb_node rb_node; /* tree information */
vaddr_t start; /* start address */
vaddr_t end; /* end address */
vsize_t gap; /* free space after */
vsize_t maxgap; /* space in subtree */
struct vm_map_entry *prev; /* previous entry */
struct vm_map_entry *next; /* next entry */
union {
struct uvm_object *uvm_obj; /* uvm object */
struct vm_map *sub_map; /* belongs to another map */
} object; /* object I point to */
voff_t offset; /* offset into object */
uint8_t etype; /* entry type */
uint8_t flags; /* flags */
uint8_t advice; /* madvise advice */
uint8_t unused; /* unused */
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 */
struct vm_aref aref; /* anonymous overlay */
};
/* flags */
#define UVM_MAP_KERNEL 0x01 /* kernel map entry */
#define UVM_MAP_STATIC 0x04 /* special static entries */
#define UVM_MAP_NOMERGE 0x08 /* this entry is not mergable */
#define VM_MAPENT_ISWIRED(entry) ((entry)->wired_count != 0)
/*
* 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.
*
* LOCKING PROTOCOL NOTES:
* -----------------------
*
* VM map locking is a little complicated. There are both shared
* and exclusive locks on maps. However, it is sometimes required
* to downgrade an exclusive lock to a shared lock, and upgrade to
* an exclusive lock again (to perform error recovery). However,
* another thread *must not* queue itself to receive an exclusive
* lock while before we upgrade back to exclusive, otherwise the
* error recovery becomes extremely difficult, if not impossible.
*
* In order to prevent this scenario, we introduce the notion of
* a `busy' map. A `busy' map is read-locked, but other threads
* attempting to write-lock wait for this flag to clear before
* entering the lock manager. A map may only be marked busy
* when the map is write-locked (and then the map must be downgraded
* to read-locked), and may only be marked unbusy by the thread
* which marked it busy (holding *either* a read-lock or a
* write-lock, the latter being gained by an upgrade).
*
* Access to the map `flags' member is controlled by the `flags_lock'
* simple lock. Note that some flags are static (set once at map
* creation time, and never changed), and thus require no locking
* to check those flags. All flags which are r/w must be set or
* cleared while the `flags_lock' is asserted. Additional locking
* requirements are:
*
* VM_MAP_PAGEABLE r/o static flag; no locking required
*
* VM_MAP_WIREFUTURE r/w; may only be set or cleared when
* map is write-locked. may be tested
* without asserting `flags_lock'.
*
* VM_MAP_DYING r/o; set when a vmspace is being
* destroyed to indicate that updates
* to the pmap can be skipped.
*
* VM_MAP_TOPDOWN r/o; set when the vmspace is
* created if the unspecified map
* allocations are to be arranged in
* a "top down" manner.
*/
struct vm_map {
struct pmap * pmap; /* Physical map */
krwlock_t lock; /* Non-intrsafe lock */
struct lwp * busy; /* LWP holding map busy */
kmutex_t misc_lock; /* Lock for cv, busy */
kcondvar_t cv; /* For signalling */
int flags; /* flags */
struct rb_tree rb_tree; /* Tree for entries */
struct vm_map_entry header; /* List of entries */
int nentries; /* Number of entries */
vsize_t size; /* virtual size */
volatile int ref_count; /* Reference count */
struct vm_map_entry * hint; /* hint for quick lookups */
struct vm_map_entry * first_free; /* First free space hint */
unsigned int timestamp; /* Version number */
};
#if defined(_KERNEL)
#include <sys/callback.h>
#endif /* defined(_KERNEL) */
#define VM_MAP_IS_KERNEL(map) (vm_map_pmap(map) == pmap_kernel())
/* vm_map flags */
#define VM_MAP_PAGEABLE 0x01 /* ro: entries are pageable */
#define VM_MAP_WIREFUTURE 0x04 /* rw: wire future mappings */
#define VM_MAP_DYING 0x20 /* rw: map is being destroyed */
#define VM_MAP_TOPDOWN 0x40 /* ro: arrange map top-down */
#define VM_MAP_WANTVA 0x100 /* rw: want va */
#define VM_MAP_BITS "\177\020\
b\0PAGEABLE\0\
b\2WIREFUTURE\0\
b\5DYING\0\
b\6TOPDOWN\0\
b\10WANTVA\0"
#ifdef _KERNEL
struct uvm_map_args {
struct vm_map_entry *uma_prev;
vaddr_t uma_start;
vsize_t uma_size;
struct uvm_object *uma_uobj;
voff_t uma_uoffset;
uvm_flag_t uma_flags;
};
#endif /* _KERNEL */
/*
* globals:
*/
#ifdef _KERNEL
#include <sys/proc.h>
#ifdef PMAP_GROWKERNEL
extern vaddr_t uvm_maxkaddr;
#endif
/*
* protos: the following prototypes define the interface to vm_map
*/
void uvm_map_deallocate(struct vm_map *);
int uvm_map_willneed(struct vm_map *, vaddr_t, vaddr_t);
int uvm_map_clean(struct vm_map *, vaddr_t, vaddr_t, int);
void uvm_map_clip_start(struct vm_map *, struct vm_map_entry *,
vaddr_t);
void uvm_map_clip_end(struct vm_map *, struct vm_map_entry *,
vaddr_t);
int uvm_map_extract(struct vm_map *, vaddr_t, vsize_t,
struct vm_map *, vaddr_t *, int);
struct vm_map_entry *
uvm_map_findspace(struct vm_map *, vaddr_t, vsize_t,
vaddr_t *, struct uvm_object *, voff_t, vsize_t, int);
int uvm_map_inherit(struct vm_map *, vaddr_t, vaddr_t,
vm_inherit_t);
int uvm_map_advice(struct vm_map *, vaddr_t, vaddr_t, int);
void uvm_map_init(void);
void uvm_map_init_caches(void);
bool uvm_map_lookup_entry(struct vm_map *, vaddr_t,
struct vm_map_entry **);
void uvm_map_reference(struct vm_map *);
int uvm_map_reserve(struct vm_map *, vsize_t, vaddr_t, vsize_t,
vaddr_t *, uvm_flag_t);
void uvm_map_setup(struct vm_map *, vaddr_t, vaddr_t, int);
int uvm_map_submap(struct vm_map *, vaddr_t, vaddr_t,
struct vm_map *);
void uvm_unmap1(struct vm_map *, vaddr_t, vaddr_t, int);
#define uvm_unmap(map, s, e) uvm_unmap1((map), (s), (e), 0)
void uvm_unmap_detach(struct vm_map_entry *,int);
void uvm_unmap_remove(struct vm_map *, vaddr_t, vaddr_t,
struct vm_map_entry **, int);
int uvm_map_prepare(struct vm_map *, vaddr_t, vsize_t,
struct uvm_object *, voff_t, vsize_t, uvm_flag_t,
struct uvm_map_args *);
int uvm_map_enter(struct vm_map *, const struct uvm_map_args *,
struct vm_map_entry *);
int uvm_mapent_trymerge(struct vm_map *,
struct vm_map_entry *, int);
#define UVM_MERGE_COPYING 1
/*
* VM map locking operations.
*/
bool vm_map_lock_try(struct vm_map *);
void vm_map_lock(struct vm_map *);
void vm_map_unlock(struct vm_map *);
void vm_map_unbusy(struct vm_map *);
void vm_map_lock_read(struct vm_map *);
void vm_map_unlock_read(struct vm_map *);
void vm_map_busy(struct vm_map *);
bool vm_map_locked_p(struct vm_map *);
void uvm_map_lock_entry(struct vm_map_entry *, krw_t);
void uvm_map_unlock_entry(struct vm_map_entry *);
#endif /* _KERNEL */
/*
* Functions implemented as macros
*/
#define vm_map_min(map) ((map)->header.end)
#define vm_map_max(map) ((map)->header.start)
#define vm_map_setmin(map, v) ((map)->header.end = (v))
#define vm_map_setmax(map, v) ((map)->header.start = (v))
#define vm_map_pmap(map) ((map)->pmap)
#endif /* _UVM_UVM_MAP_H_ */
