[xen master] tools: Make init-xenstore-domain use xc_domain_getinfolist()

[patchbot@xxxxxxx]

commit 5a8efb1bd092a0f579cc3306226868346b73f362
Author:     Alejandro Vallejo <alejandro.vallejo@xxxxxxxxx>
AuthorDate: Fri Apr 28 11:41:21 2023 +0100
Commit:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
CommitDate: Fri Apr 28 14:34:40 2023 +0100

    tools: Make init-xenstore-domain use xc_domain_getinfolist()
    
    It currently relies on xc_domain_getinfo() returning the next available
    domain past "first_domid", which is a feature that will disappear in a
    future patch.
    
    Furthermore and while at it, make it so the hypercall tries to fetch 
information
    about more than one domain per hypercall so we can (hopefully) get away 
with a
    single hypercall in a typical system.
    
    Signed-off-by: Alejandro Vallejo <alejandro.vallejo@xxxxxxxxx>
    Reviewed-by: Juergen Gross <jgross@xxxxxxxx>
    Reviewed-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
 tools/helpers/init-xenstore-domain.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/tools/helpers/init-xenstore-domain.c 
b/tools/helpers/init-xenstore-domain.c
index 0950ba7dc5..b2d5df8ba5 100644
--- a/tools/helpers/init-xenstore-domain.c
+++ b/tools/helpers/init-xenstore-domain.c
@@ -13,6 +13,7 @@
 #include <xentoollog.h>
 #include <libxl.h>
 #include <xen/sys/xenbus_dev.h>
+#include <xen-tools/common-macros.h>
 #include <xen-xsm/flask/flask.h>
 #include <xen/io/xenbus.h>
 
@@ -322,16 +323,20 @@ err:
 
 static int check_domain(xc_interface *xch)
 {
-    xc_dominfo_t info;
+    /* Commonly dom0 is the only domain, but buffer a little for efficiency. */
+    xc_domaininfo_t info[8];
     uint32_t dom;
     int ret;
 
     dom = 1;
-    while ( (ret = xc_domain_getinfo(xch, dom, 1, &info)) == 1 )
+    while ( (ret = xc_domain_getinfolist(xch, dom, ARRAY_SIZE(info), info)) > 
0 )
     {
-        if ( info.xenstore )
-            return 1;
-        dom = info.domid + 1;
+        for ( size_t i = 0; i < ret; i++ )
+        {
+            if ( info[i].flags & XEN_DOMINF_xs_domain )
+                return 1;
+        }
+        dom = info[ret - 1].domain + 1;
     }
     if ( ret < 0 && errno != ESRCH )
     {
--
generated by git-patchbot for /home/xen/git/xen.git#master