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34 .Nd "allocate a page for a"
41 .Fn vm_page_alloc "vm_object_t object" "vm_pindex_t pindex" "int page_req"
45 function allocates a page at
49 It is assumed that a page has not already been allocated at
51 The page returned is inserted into the object, unless
55 but is not inserted into a pmap.
56 The page may exists in the vm object cache, in which case it will
57 be reactivated instead, moving from the cache into the object page list.
63 .Bl -tag -width ".Fa page_req"
65 The VM object to allocate the page for.
72 The index into the object at which the page should be inserted.
74 A flag indicating how the page should be allocated.
75 .Bl -tag -width ".Dv VM_ALLOC_INTERRUPT"
76 .It Dv VM_ALLOC_NORMAL
77 The page should be allocated with no special treatment.
78 .It Dv VM_ALLOC_SYSTEM
79 The page can be allocated if the cache queue is empty and the free
80 page count is above the interrupt reserved water mark.
82 .Dv VM_ALLOC_INTERRUPT
83 is set, the page can be allocated as long as the free page count is
85 This flag should be used only when the system really needs the page.
86 .It Dv VM_ALLOC_INTERRUPT
88 is being called during an interrupt and therefore the cache cannot
90 The page will only be returned successfully if the free count is greater
93 Indicate a preference for a pre-zeroed page.
94 There is no guarantee that the page thus returned will be zeroed, but
99 Do not associate the allocated page with a vm object.
103 .It Dv VM_ALLOC_NOBUSY
104 The page returned will not be busied.
105 .It Dv VM_ALLOC_WIRED
106 The returned page is wired.
107 .It Dv VM_ALLOC_IFNOTCACHED
108 Only allocate the page if it is not cached in the
110 If the page at the specified
112 is cached, NULL is returned instead.
118 that was allocated is returned if successful; otherwise,
122 The pager process is always upgraded to
125 .Dv VM_ALLOC_INTERRUPT
128 This manual page was written by
129 .An Chad David Aq davidc@acns.ab.ca .