device-mapper-multipath/0021-libmultipath-adapt-to-new-semantics-of-dm_get_uuid.patch

159 lines
5.4 KiB
Diff
Raw Normal View History

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Martin Wilck <mwilck@suse.com>
Date: Mon, 28 Aug 2023 12:26:37 +0200
Subject: [PATCH] libmultipath: adapt to new semantics of dm_get_uuid()
dm_get_uuid() will return 1 for non-existing maps. Thus we don't need
to call dm_map_present() any more in alias_already_taken(). This changes
our semantics: previously we'd avoid using an alias for which dm_get_uuid()
had failed. Now we treat failure in dm_get_uuid() as indication that the
map doesn't exist. This is not dangerous because dm_task_get_uuid() cannot
fail, and thus the modified dm_get_uuid() will fail if and only if
dm_map_present() would return false.
This makes the "failed alias" test mostly obsolete, as "failed" is now
treated as "unused".
Signed-off-by: Martin Wilck <mwilck@suse.com>
Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
---
libmultipath/alias.c | 25 +++++++++++++------------
tests/alias.c | 32 +++++++-------------------------
2 files changed, 20 insertions(+), 37 deletions(-)
diff --git a/libmultipath/alias.c b/libmultipath/alias.c
index d6563749..58436ec0 100644
--- a/libmultipath/alias.c
+++ b/libmultipath/alias.c
@@ -295,18 +295,19 @@ scan_devname(const char *alias, const char *prefix)
static bool alias_already_taken(const char *alias, const char *map_wwid)
{
- if (dm_map_present(alias)) {
- char wwid[WWID_SIZE];
-
- /* If both the name and the wwid match, then it's fine.*/
- if (dm_get_uuid(alias, wwid, sizeof(wwid)) == 0 &&
- strncmp(map_wwid, wwid, sizeof(wwid)) == 0)
- return false;
- condlog(3, "%s: alias '%s' already taken, reselecting alias",
- map_wwid, alias);
- return true;
- }
- return false;
+ char wwid[WWID_SIZE];
+
+ /* If the map doesn't exist, it's fine */
+ if (dm_get_uuid(alias, wwid, sizeof(wwid)) != 0)
+ return false;
+
+ /* If both the name and the wwid match, it's fine.*/
+ if (strncmp(map_wwid, wwid, sizeof(wwid)) == 0)
+ return false;
+
+ condlog(3, "%s: alias '%s' already taken, reselecting alias",
+ map_wwid, alias);
+ return true;
}
static bool id_already_taken(int id, const char *prefix, const char *map_wwid)
diff --git a/tests/alias.c b/tests/alias.c
index 50a21ecf..d1cc487b 100644
--- a/tests/alias.c
+++ b/tests/alias.c
@@ -73,12 +73,6 @@ int __wrap_mkstemp(char *template)
return 10;
}
-int __wrap_dm_map_present(const char * str)
-{
- check_expected(str);
- return mock_type(int);
-}
-
int __wrap_dm_get_uuid(const char *name, char *uuid, int uuid_len)
{
int ret;
@@ -398,14 +392,13 @@ static int test_scan_devname(void)
static void mock_unused_alias(const char *alias)
{
- expect_string(__wrap_dm_map_present, str, alias);
- will_return(__wrap_dm_map_present, 0);
+ expect_string(__wrap_dm_get_uuid, name, alias);
+ expect_value(__wrap_dm_get_uuid, uuid_len, WWID_SIZE);
+ will_return(__wrap_dm_get_uuid, 1);
}
static void mock_self_alias(const char *alias, const char *wwid)
{
- expect_string(__wrap_dm_map_present, str, alias);
- will_return(__wrap_dm_map_present, 1);
expect_string(__wrap_dm_get_uuid, name, alias);
expect_value(__wrap_dm_get_uuid, uuid_len, WWID_SIZE);
will_return(__wrap_dm_get_uuid, 0);
@@ -432,18 +425,13 @@ static void mock_self_alias(const char *alias, const char *wwid)
#define mock_failed_alias(alias, wwid) \
do { \
- expect_string(__wrap_dm_map_present, str, alias); \
- will_return(__wrap_dm_map_present, 1); \
expect_string(__wrap_dm_get_uuid, name, alias); \
expect_value(__wrap_dm_get_uuid, uuid_len, WWID_SIZE); \
will_return(__wrap_dm_get_uuid, 1); \
- expect_condlog(3, USED_STR(alias, wwid)); \
} while (0)
#define mock_used_alias(alias, wwid) \
do { \
- expect_string(__wrap_dm_map_present, str, alias); \
- will_return(__wrap_dm_map_present, 1); \
expect_string(__wrap_dm_get_uuid, name, alias); \
expect_value(__wrap_dm_get_uuid, uuid_len, WWID_SIZE); \
will_return(__wrap_dm_get_uuid, 0); \
@@ -566,9 +554,8 @@ static void lb_empty_failed(void **state)
mock_bindings_file("");
expect_condlog(3, NOMATCH_WWID_STR("WWID0"));
mock_failed_alias("MPATHa", "WWID0");
- mock_unused_alias("MPATHb");
rc = lookup_binding(NULL, "WWID0", &alias, "MPATH", 1);
- assert_int_equal(rc, 2);
+ assert_int_equal(rc, 1);
assert_ptr_equal(alias, NULL);
free(alias);
}
@@ -666,9 +653,8 @@ static void lb_nomatch_a_3_used_failed_self(void **state)
mock_used_alias("MPATHc", "WWID1");
mock_used_alias("MPATHd", "WWID1");
mock_failed_alias("MPATHe", "WWID1");
- mock_self_alias("MPATHf", "WWID1");
rc = lookup_binding(NULL, "WWID1", &alias, "MPATH", 1);
- assert_int_equal(rc, 6);
+ assert_int_equal(rc, 5);
assert_ptr_equal(alias, NULL);
}
@@ -940,7 +926,7 @@ static void lb_nomatch_b_a_aa(void **state)
static void lb_nomatch_b_a_aa_zz(void **state)
{
- int rc, i;
+ int rc;
char *alias;
STRBUF_ON_STACK(buf);
@@ -949,11 +935,7 @@ static void lb_nomatch_b_a_aa_zz(void **state)
* lookup_binding finds MPATHaaa as next free entry, because MPATHaa is
* found before MPATHb, and MPATHzz was in the bindings, too.
*/
- for (i = 0; i <= 26; i++) {
- print_strbuf(&buf, "MPATH");
- format_devname(&buf, i + 1);
- print_strbuf(&buf, " WWID%d\n", i);
- }
+ fill_bindings(&buf, 0, 26);
print_strbuf(&buf, "MPATHzz WWID676\n");
mock_bindings_file(get_strbuf_str(&buf));
expect_condlog(3, NOMATCH_WWID_STR("WWID703"));