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| author | mlaier <mlaier@FreeBSD.org> | 2010-12-09 21:02:22 +0000 |
|---|---|---|
| committer | mlaier <mlaier@FreeBSD.org> | 2010-12-09 21:02:22 +0000 |
| commit | da2dde653e0b4157a383ca260e51c5bcf85a7414 (patch) | |
| tree | 7178a019174177fb597d3725c8f21cebe38f24ae /sys/vm/vm_map.h | |
| parent | c3ffedd66b60efcf18ea15901fee16f8cbd58649 (diff) | |
| download | FreeBSD-src-da2dde653e0b4157a383ca260e51c5bcf85a7414.zip FreeBSD-src-da2dde653e0b4157a383ca260e51c5bcf85a7414.tar.gz | |
Fix a long standing (from the original 4.4BSD lite sources) race between
vmspace_fork and vm_map_wire that would lead to "vm_fault_copy_wired: page
missing" panics. While faulting in pages for a map entry that is being
wired down, mark the containing map as busy. In vmspace_fork wait until the
map is unbusy, before we try to copy the entries.
Reviewed by: kib
MFC after: 5 days
Sponsored by: Isilon Systems, Inc.
Diffstat (limited to 'sys/vm/vm_map.h')
| -rw-r--r-- | sys/vm/vm_map.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/sys/vm/vm_map.h b/sys/vm/vm_map.h index f7fc5f5..fecbffe 100644 --- a/sys/vm/vm_map.h +++ b/sys/vm/vm_map.h @@ -187,12 +187,14 @@ struct vm_map { pmap_t pmap; /* (c) Physical map */ #define min_offset header.start /* (c) */ #define max_offset header.end /* (c) */ + int busy; }; /* * vm_flags_t values */ #define MAP_WIREFUTURE 0x01 /* wire all future pages */ +#define MAP_BUSY_WAKEUP 0x02 #ifdef _KERNEL static __inline vm_offset_t @@ -275,6 +277,9 @@ int _vm_map_lock_upgrade(vm_map_t map, const char *file, int line); void _vm_map_lock_downgrade(vm_map_t map, const char *file, int line); int vm_map_locked(vm_map_t map); void vm_map_wakeup(vm_map_t map); +void vm_map_busy(vm_map_t map); +void vm_map_unbusy(vm_map_t map); +void vm_map_wait_busy(vm_map_t map); #define vm_map_lock(map) _vm_map_lock(map, LOCK_FILE, LOCK_LINE) #define vm_map_unlock(map) _vm_map_unlock(map, LOCK_FILE, LOCK_LINE) |
