[PATCH v3 storage 04/76] storage: distinguish status-only activation in plugins

[Thomas Lamprecht <t.lamprecht@proxmox.com>]

pvestatd, the storage index API, and 'pvesm status' activate enabled
storages to collect status. Plugins cannot distinguish this from
activation for actual use, such as starting a guest. Waiting for a
missing device can therefore stall every status pass, while skipping
the wait can make guest startup fail immediately after boot.

Mark status-only activation in the cache and pass it to
check_connection() too, so plugins can choose whether to wait. Plugins
that ignore the new information are unaffected. Bump APIVER and APIAGE
for the plugin API extension.

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
 ApiChangeLog              | 24 ++++++++++++++++++++++++
 src/PVE/Storage.pm        |  9 +++++----
 src/PVE/Storage/Plugin.pm |  2 +-
 3 files changed, 30 insertions(+), 5 deletions(-)

diff --git a/ApiChangeLog b/ApiChangeLog
index e9fbcabe..83dda939 100644
--- a/ApiChangeLog
+++ b/ApiChangeLog
@@ -6,6 +6,30 @@ without breaking anything unaware of it.)
 
 Future changes should be documented in here.
 
+## Version 17:
+
+* Pass the activation cache to the `check_connection()` plugin method
+
+  Old signature of `check_connection()`:
+
+    sub($plugin, $storeid, $scfg)
+
+  New signature of `check_connection()`:
+
+    sub($plugin, $storeid, $scfg, $cache)
+
+  It is the cache of the activation that calls it, the same one the following
+  `activate_storage()` call gets. Plugins that do not need it can ignore the additional parameter.
+
+* Add the `status_only` flag to the activation cache
+
+  `PVE::Storage::storage_info()`, which collects the status of the storages for pvestatd, the
+  storage index API and `pvesm status`, sets `$cache->{status_only}` in the cache it activates the
+  storages with. Plugins can check it in `check_connection()` and `activate_storage()` to skip
+  waiting for what only a use of the storage needs, for example a device that is still appearing,
+  so a storage that cannot get ready does not stall the status updates of the node. Plugins that
+  do not check it are not affected.
+
 ## Version 16:
 
 * Add `volname_for_format()`, `get_parsed_format()`, `volname_with_format()`, `is_valid_format()` and
diff --git a/src/PVE/Storage.pm b/src/PVE/Storage.pm
index d660cfc4..891d1885 100755
--- a/src/PVE/Storage.pm
+++ b/src/PVE/Storage.pm
@@ -41,11 +41,11 @@ use PVE::Storage::BTRFSPlugin;
 use PVE::Storage::ESXiPlugin;
 
 # Storage API version. Increment it on changes in storage API interface.
-use constant APIVER => 16;
+use constant APIVER => 17;
 # Age is the number of versions we're backward compatible with.
 # This is like having 'current=APIVER' and age='APIAGE' in libtool,
 # see https://www.gnu.org/software/libtool/manual/html_node/Libtool-versioning.html
-use constant APIAGE => 7;
+use constant APIAGE => 8;
 
 our $KNOWN_EXPORT_FORMATS = ['raw+size', 'tar+size', 'qcow2+size', 'vmdk+size', 'zfs', 'btrfs'];
 
@@ -1356,7 +1356,7 @@ sub activate_storage {
         activate_storage($cfg, $baseid, $cache);
     }
 
-    if (!eval { $plugin->check_connection($storeid, $scfg) }) {
+    if (!eval { $plugin->check_connection($storeid, $scfg, $cache) }) {
         die "connection check for storage '$storeid' failed - $@\n" if $@;
         die "storage '$storeid' is not online\n";
     }
@@ -1485,7 +1485,8 @@ sub storage_info {
         push @$slist, $storeid;
     }
 
-    my $cache = {};
+    # Status-only activation must not wait for resources needed only when using a storage.
+    my $cache = { status_only => 1 };
 
     foreach my $storeid (keys %$ids) {
         my $scfg = $ids->{$storeid};
diff --git a/src/PVE/Storage/Plugin.pm b/src/PVE/Storage/Plugin.pm
index 3d07f749..bec8ae7a 100644
--- a/src/PVE/Storage/Plugin.pm
+++ b/src/PVE/Storage/Plugin.pm
@@ -2169,7 +2169,7 @@ sub deactivate_volume {
 }
 
 sub check_connection {
-    my ($class, $storeid, $scfg) = @_;
+    my ($class, $storeid, $scfg, $cache) = @_;
     # do nothing by default
     return 1;
 }
-- 
2.47.3