xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

xen-gntdev: Support mapping in HVM domains

Browse Source 
HVM does not allow direct PTE modification, so instead we request
that Xen change its internal p2m mappings on the allocated pages and
map the memory into userspace normally.

Note:
The HVM path for map and unmap is slightly different: HVM keeps the pages
mapped until the area is deleted, while the PV case (use_ptemod being true)
must unmap them when userspace unmaps the range. In the normal use case,
this makes no difference to users since unmap time is deletion time.

[v2: Expanded commit descr.]
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This commit is contained in:
Daniel De Graaf
2011-02-03 12:19:02 -05:00
committed by Konrad Rzeszutek Wilk
parent 68b025c813
commit aab8f11a6b
2 changed files with 89 additions and 34 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
drivers/xen/grant-table.c
View File

@@ -458,6 +458,9 @@ int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
if (ret)
return ret;
if (xen_feature(XENFEAT_auto_translated_physmap))
return ret;
for (i = 0; i < count; i++) {
/* m2p override only supported for GNTMAP_contains_pte mappings */
if (!(map_ops[i].flags & GNTMAP_contains_pte))
@@ -483,6 +486,9 @@ int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops,
if (ret)
return ret;
if (xen_feature(XENFEAT_auto_translated_physmap))
return ret;
for (i = 0; i < count; i++) {
ret = m2p_remove_override(pages[i]);
if (ret)