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27 .\" $FreeBSD: src/share/man/man9/vm_page_alloc.9,v 1.6 2005/06/28 20:15:18 hmp Exp $
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, but is not inserted
52 into the pmap. The vm_object must be locked on entry.
58 .Bl -tag -width ".Fa page_req"
60 The VM object to allocate the page for.
62 The index into the object at which the page should be inserted.
64 A flag indicating how the page should be allocated.
65 .Bl -tag -width ".Dv VM_ALLOC_INTERRUPT"
66 .It Dv VM_ALLOC_NORMAL
67 The page should be allocated with no special treatment.
69 The page should only be allocated from the free queue.
70 .It Dv VM_ALLOC_SYSTEM
71 The page can be allocated if the cache queue is empty and the free
72 page count is above the interrupt reserved water mark.
74 .Dv VM_ALLOC_INTERRUPT
75 is set, the page can be allocated as long as the free page count is
77 This flag should be used only when the system really needs the page.
78 .It Dv VM_ALLOC_INTERRUPT
80 is being called during an interrupt and therefore the cache cannot
82 The page will only be returned successfully if the free count is greater
85 Indicate a preference for a pre-zeroed page.
86 There is no guarantee that the page thus returned will be zeroed, but
87 it will be marked as such.
93 that was allocated is returned if successful; otherwise,
95 is returned. The returned page will be marked PG_BUSY.
97 This manual page was written by
98 .An Chad David Aq davidc@acns.ab.ca .