scsi/qemu-pr-helper: Drop support for 'old' libmultipath API

Commit 1b0578f ("qemu-pr-helper: Fix build on CentOS 7") added
code to probe for 'old' libmultipath API on CentOS 7. However since
merge commit 8c345b3 (June 2021) we don't build/test CentOS 7 as
it felt out of our list of supported distrib versions. Therefore we
can safely remove the 'old' API check (mostly reverting commit
1b0578f, except the code got converted to meson in commit
6ec0e15 "meson: move libmpathpersist test").

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230605174146.87440-2-philmd@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

meson.build

@@ -1092,9 +1092,8 @@ endif
 
 mpathlibs = [libudev]
 mpathpersist = not_found
-mpathpersist_new_api = false
 if targetos == 'linux' and have_tools and get_option('mpath').allowed()
-  mpath_test_source_new = '''
+  mpath_test_source = '''
     #include <libudev.h>
     #include <mpath_persist.h>
     unsigned mpath_mx_alloc_len = 1024;
@@ -1111,16 +1110,6 @@ if targetos == 'linux' and have_tools and get_option('mpath').allowed()
         multipath_conf = mpath_lib_init();
         return 0;
     }'''
-  mpath_test_source_old = '''
-      #include <libudev.h>
-      #include <mpath_persist.h>
-      unsigned mpath_mx_alloc_len = 1024;
-      int logsink;
-      int main(void) {
-          struct udev *udev = udev_new();
-          mpath_lib_init(udev);
-          return 0;
-      }'''
   libmpathpersist = cc.find_library('mpathpersist',
                                     required: get_option('mpath'))
   if libmpathpersist.found()
@@ -1139,10 +1128,7 @@ if targetos == 'linux' and have_tools and get_option('mpath').allowed()
     endforeach
     if mpathlibs.length() == 0
       msg = 'Dependencies missing for libmpathpersist'
-    elif cc.links(mpath_test_source_new, dependencies: mpathlibs)
-      mpathpersist = declare_dependency(dependencies: mpathlibs)
-      mpathpersist_new_api = true
-    elif cc.links(mpath_test_source_old, dependencies: mpathlibs)
+    elif cc.links(mpath_test_source, dependencies: mpathlibs)
       mpathpersist = declare_dependency(dependencies: mpathlibs)
     else
       msg = 'Cannot detect libmpathpersist API'
@@ -2094,7 +2080,6 @@ config_host_data.set('CONFIG_GCOV', get_option('b_coverage'))
 config_host_data.set('CONFIG_LIBUDEV', libudev.found())
 config_host_data.set('CONFIG_LZO', lzo.found())
 config_host_data.set('CONFIG_MPATH', mpathpersist.found())
-config_host_data.set('CONFIG_MPATH_NEW_API', mpathpersist_new_api)
 config_host_data.set('CONFIG_BLKIO', blkio.found())
 if blkio.found()
   config_host_data.set('CONFIG_BLKIO_VHOST_VDPA_FD',

scsi/qemu-pr-helper.c

@@ -280,11 +280,7 @@ void put_multipath_config(struct config *conf)
 static void multipath_pr_init(void)
 {
     udev = udev_new();
-#ifdef CONFIG_MPATH_NEW_API
     multipath_conf = mpath_lib_init();
-#else
-    mpath_lib_init(udev);
-#endif
 }
 
 static int is_mpath(int fd)