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| author | Alex Nixon <alex.nixon@citrix.com> | 2009-02-09 23:05:46 +0300 |
|---|---|---|
| committer | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2010-06-07 23:37:53 +0400 |
| commit | 08bbc9da92f7e44b9c208c6a1adba70c403b255e (patch) | |
| tree | 75c6cf9422e03990d1fd280b631d00ea4d4dbe4b /include/xen/interface/memory.h | |
| parent | 19001c8c5bfa032ed45b10dfe48e355f5df88c61 (diff) | |
| download | linux-08bbc9da92f7e44b9c208c6a1adba70c403b255e.tar.xz | |
xen: Add xen_create_contiguous_region
A memory region must be physically contiguous in order to be accessed
through DMA. This patch adds xen_create_contiguous_region, which
ensures a region of contiguous virtual memory is also physically
contiguous.
Based on Stephen Tweedie's port of the 2.6.18-xen version.
Remove contiguous_bitmap[] as it's no longer needed.
Ported from linux-2.6.18-xen.hg 707:e410857fd83c
[ Impact: add Xen-internal API to make pages phys-contig ]
Signed-off-by: Alex Nixon <alex.nixon@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Diffstat (limited to 'include/xen/interface/memory.h')
| -rw-r--r-- | include/xen/interface/memory.h | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/include/xen/interface/memory.h b/include/xen/interface/memory.h index e6adce6bc75c..d3938d3e71f8 100644 --- a/include/xen/interface/memory.h +++ b/include/xen/interface/memory.h @@ -55,6 +55,48 @@ struct xen_memory_reservation { DEFINE_GUEST_HANDLE_STRUCT(xen_memory_reservation); /* + * An atomic exchange of memory pages. If return code is zero then + * @out.extent_list provides GMFNs of the newly-allocated memory. + * Returns zero on complete success, otherwise a negative error code. + * On complete success then always @nr_exchanged == @in.nr_extents. + * On partial success @nr_exchanged indicates how much work was done. + */ +#define XENMEM_exchange 11 +struct xen_memory_exchange { + /* + * [IN] Details of memory extents to be exchanged (GMFN bases). + * Note that @in.address_bits is ignored and unused. + */ + struct xen_memory_reservation in; + + /* + * [IN/OUT] Details of new memory extents. + * We require that: + * 1. @in.domid == @out.domid + * 2. @in.nr_extents << @in.extent_order == + * @out.nr_extents << @out.extent_order + * 3. @in.extent_start and @out.extent_start lists must not overlap + * 4. @out.extent_start lists GPFN bases to be populated + * 5. @out.extent_start is overwritten with allocated GMFN bases + */ + struct xen_memory_reservation out; + + /* + * [OUT] Number of input extents that were successfully exchanged: + * 1. The first @nr_exchanged input extents were successfully + * deallocated. + * 2. The corresponding first entries in the output extent list correctly + * indicate the GMFNs that were successfully exchanged. + * 3. All other input and output extents are untouched. + * 4. If not all input exents are exchanged then the return code of this + * command will be non-zero. + * 5. THIS FIELD MUST BE INITIALISED TO ZERO BY THE CALLER! + */ + unsigned long nr_exchanged; +}; + +DEFINE_GUEST_HANDLE_STRUCT(xen_memory_exchange); +/* * Returns the maximum machine frame number of mapped RAM in this system. * This command always succeeds (it never returns an error code). * arg == NULL. |