diff options
| -rw-r--r-- | sys/uvm/uvm_map.c | 37 |
1 files changed, 28 insertions, 9 deletions
diff --git a/sys/uvm/uvm_map.c b/sys/uvm/uvm_map.c index ebc1318b1ec..f73e968538c 100644 --- a/sys/uvm/uvm_map.c +++ b/sys/uvm/uvm_map.c @@ -1,4 +1,4 @@ -/* $OpenBSD: uvm_map.c,v 1.158 2012/10/18 08:46:23 gerhard Exp $ */ +/* $OpenBSD: uvm_map.c,v 1.159 2013/02/10 19:19:30 beck Exp $ */ /* $NetBSD: uvm_map.c,v 1.86 2000/11/27 08:40:03 chs Exp $ */ /* @@ -121,7 +121,7 @@ struct vm_map_entry *uvm_mapent_tryjoin(struct vm_map*, struct vm_map_entry*, struct uvm_map_deadq*); struct vm_map_entry *uvm_map_mkentry(struct vm_map*, struct vm_map_entry*, struct vm_map_entry*, vaddr_t, vsize_t, int, - struct uvm_map_deadq*); + struct uvm_map_deadq*, struct vm_map_entry*); struct vm_map_entry *uvm_mapent_alloc(struct vm_map*, int); void uvm_mapent_free(struct vm_map_entry*); void uvm_unmap_kill_entry(struct vm_map*, @@ -961,7 +961,7 @@ int uvm_map(struct vm_map *map, vaddr_t *addr, vsize_t sz, struct uvm_object *uobj, voff_t uoffset, vsize_t align, uvm_flag_t flags) { - struct vm_map_entry *first, *last, *entry; + struct vm_map_entry *first, *last, *entry, *new; struct uvm_map_deadq dead; vm_prot_t prot; vm_prot_t maxprot; @@ -1037,9 +1037,20 @@ uvm_map(struct vm_map *map, vaddr_t *addr, vsize_t sz, if ((prot & maxprot) != prot) return EACCES; + /* + * Before grabbing the lock, allocate a map entry for later + * use to ensure we don't wait for memory while holding the + * vm_map_lock. + */ + new = uvm_mapent_alloc(map, flags); + if (new == NULL) + return(ENOMEM); + if (flags & UVM_FLAG_TRYLOCK) { - if (vm_map_lock_try(map) == FALSE) - return EFAULT; + if (vm_map_lock_try(map) == FALSE) { + error = EFAULT; + goto out; + } } else vm_map_lock(map); @@ -1147,11 +1158,13 @@ uvm_map(struct vm_map *map, vaddr_t *addr, vsize_t sz, * Create new entry. * first and last may be invalidated after this call. */ - entry = uvm_map_mkentry(map, first, last, *addr, sz, flags, &dead); + entry = uvm_map_mkentry(map, first, last, *addr, sz, flags, &dead, + new); if (entry == NULL) { error = ENOMEM; goto unlock; } + new = NULL; KDASSERT(entry->start == *addr && entry->end == *addr + sz); entry->object.uvm_obj = uobj; entry->offset = uoffset; @@ -1209,6 +1222,9 @@ unlock: * destroy free-space entries. */ uvm_unmap_detach(&dead, 0); +out: + if (new) + uvm_mapent_free(new); return error; } @@ -1407,7 +1423,7 @@ uvm_unmap_detach(struct uvm_map_deadq *deadq, int flags) struct vm_map_entry* uvm_map_mkentry(struct vm_map *map, struct vm_map_entry *first, struct vm_map_entry *last, vaddr_t addr, vsize_t sz, int flags, - struct uvm_map_deadq *dead) + struct uvm_map_deadq *dead, struct vm_map_entry *new) { struct vm_map_entry *entry, *prev; struct uvm_addr_state *free; @@ -1430,7 +1446,10 @@ uvm_map_mkentry(struct vm_map *map, struct vm_map_entry *first, /* * Initialize new entry. */ - entry = uvm_mapent_alloc(map, flags); + if (new == NULL) + entry = uvm_mapent_alloc(map, flags); + else + entry = new; if (entry == NULL) return NULL; entry->offset = 0; @@ -3283,7 +3302,7 @@ uvm_mapent_clone(struct vm_map *dstmap, vaddr_t dstaddr, vsize_t dstlen, "entry in empty map"); } new_entry = uvm_map_mkentry(dstmap, first, last, - dstaddr, dstlen, mapent_flags, dead); + dstaddr, dstlen, mapent_flags, dead, NULL); if (new_entry == NULL) return NULL; /* old_entry -> new_entry */ |