From: Penny Zheng <Penny.Zheng@arm.com>
Date: Thu, 8 Sep 2022 13:55:10 +0000 (+0800)
Subject: xen/arm: set up shared memory foreign mapping for borrower domain
X-Git-Tag: archive/raspbian/4.17.0-1+rpi1^2~33^2~199
X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/%22/%22http:/www.example.com/cgi/%22?a=commitdiff_plain;h=b7133c10a3fd3b66b8d6a657a55855ab78f0a75b;p=xen.git

xen/arm: set up shared memory foreign mapping for borrower domain

This commit sets up shared memory foreign mapping for borrower domain.

If owner domain is the default dom_io, all shared domain are treated as
borrower domain.

Signed-off-by: Penny Zheng <penny.zheng@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
---

diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 417a0e82ba..dfcda604b3 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -992,6 +992,15 @@ static int __init process_shm(struct domain *d,
             if ( ret )
                 return ret;
         }
+
+        if ( owner_dom_io || (strcmp(role_str, "borrower") == 0) )
+        {
+            /* Set up P2M foreign mapping for borrower domain. */
+            ret = map_regions_p2mt(d, _gfn(PFN_UP(gbase)), PFN_DOWN(psize),
+                                   _mfn(PFN_UP(pbase)), p2m_map_foreign_rw);
+            if ( ret )
+                return ret;
+        }
     }
 
     return 0;