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33 .Nm pmap_extract_and_hold
34 .Nd map a virtual address to a physical page
40 .Fn pmap_extract "pmap_t pmap" "vm_offset_t va"
42 .Fn pmap_extract_and_hold "pmap_t pmap" "vm_offset_t va" "vm_prot_t prot"
46 function maps a virtual address to a physical page.
47 In certain situations, callers may use
48 .Fn pmap_extract_and_hold
49 instead, to ensure that the returned page is held.
52 .Fn pmap_extract_and_hold
53 function maps a virtual address to a physical page, and atomically holds
54 the returned page for use by the caller, only if the mapping permits
55 the given page protection.
56 .Sh IMPLEMENTATION NOTES
57 Currently, the page protection requested by the caller is not verified.
60 .Fn pmap_extract_and_hold
63 lock is held for the duration of the call to ensure that only a single
68 function will return the physical page address associated with the
71 inside the physical map
73 If the mapping does not exist, or if the
82 .Fn pmap_extract_and_hold
83 function will return the physical page address associated with the
86 inside the physical map
88 If the mapping does not exist, the result is a no-op, and
98 .Fn pmap_extract_and_hold
99 function was implemented by
100 .An Alan L. Cox Aq alc@imimic.com .
101 This manual page was written by
102 .An Bruce M Simpson Aq bms@spc.org .