ia64/xen-unstable

view xen/GUEST_CHANGES @ 806:ac55fdc43f08

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GUEST_CHANGES:
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author kaf24@scramble.cl.cam.ac.uk
date Wed Oct 08 13:42:44 2003 +0000 (2003-10-08)
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2 The interface between Xen and overlying guest OSes has changed in the
3 following ways since version 1.0:
5 Modified hypercall 'pt_update'
6 ------------------------------
7 Page-table updates passed to the 'pt_update' hypercall must now
8 specify a virtual address that maps the PTE to be modified. Previously
9 a physical address was used, requiring Xen to temporarily map the PTE
10 into its own private region so that it could be read and written.
11 This affects only commands of type PGREQ_NORMAL_UPDATE and
12 PGREQ_UNCHECKED_UPDATE.
14 New hypercall 'update_va_mapping'
15 ---------------------------------
16 A new high-speed page-table update method has been introduced, which
17 may be of particular benefit when fixing up application page faults.
18 Invoked as 'update_va_mapping(page_number, new_pte_value, flags)':
19 <page_number>: The virtual page number in the current address space
20 whose PTE is to be modified.
21 <new_pte_value>: The new value to write into the PTE.
22 <flags>: An ORed combination of
23 UVMF_INVLPG: Flush stale TLB entry of the updated page mapping
24 UVMF_FLUSH_TLB: Flush all TLB entries
25 You can see this new call in use in Xenolinux (common/memory.c).