vdo: read VDO stats via dm message

As the sysfs interface is seen somewhat obsolete, swith code
to prefer using DM 'stats' message to get our currently needed
info for VDO pool target.

diff --git a/lib/activate/dev_manager.c b/lib/activate/dev_manager.c
index 9b1dcd2500d5aba73577e4e55e143381f506ce75..4da2a0ad79621b7af4027d997a61f24c9bd76173 100644 (file)
--- a/lib/activate/dev_manager.c
+++ b/lib/activate/dev_manager.c
@@ -1905,6 +1905,60 @@ out:
        return r;
 }
 
+/* Read info from DM VDO 'stats' message */
+static int _dev_manager_vdo_pool_message_stats(struct dev_manager *dm,
+                                              const struct logical_volume *lv,
+                                              struct lv_status_vdo *status)
+{
+       const char *response;
+       const char *dlid;
+       struct dm_task *dmt = NULL;
+       int r = 0;
+       unsigned i;
+       const char *p;
+       struct vdo_msg_elem {
+               const char *name;
+               uint64_t *val;
+       } const vme[] = {
+               { "dataBlocksUsed", &status->data_blocks_used },
+               { "logicalBlocksUsed", &status->logical_blocks_used }
+       };
+
+       if (!(dlid = build_dm_uuid(dm->mem, lv, lv_layer(lv))))
+               return_0;
+
+       if (!(dmt = _setup_task_run(DM_DEVICE_TARGET_MSG, NULL, NULL, dlid, 0, 0, 0, 0, 0, 0)))
+               return_0;
+
+       if (!dm_task_set_message(dmt, "stats"))
+               goto_out;
+
+       if (!dm_task_run(dmt))
+               goto_out;
+
+       log_debug_activation("Checking VDO pool stats message for LV %s.",
+                            display_lvname(lv));
+
+       if ((response = dm_task_get_message_response(dmt))) {
+               for (i = 0; i < DM_ARRAY_SIZE(vme); ++i) {
+                       errno = 0;
+                       if (!(p = strstr(response,  vme[i].name)) ||
+                           !(p = strchr(p, ':')) ||
+                           ((*vme[i].val = strtoul(p + 1, NULL, 10)) == ULLONG_MAX) || errno) {
+                               log_debug("Cannot parse %s in VDO DM stats message.", vme[i].name);
+                               *vme[i].val = 0;
+                               goto out;
+                       }
+               }
+       }
+
+       r = 1;
+out:
+       dm_task_destroy(dmt);
+
+       return r;
+}
+
 int dev_manager_vdo_pool_status(struct dev_manager *dm,
                                const struct logical_volume *lv, int flush,
                                struct lv_status_vdo **status, int *exists)
@@ -1945,6 +1999,9 @@ int dev_manager_vdo_pool_status(struct dev_manager *dm,
                goto out;
        }
 
+       if (!_dev_manager_vdo_pool_message_stats(dm, lv, *status))
+               stack;
+
        if (!parse_vdo_pool_status(dm->mem, lv, params, &info, *status))
                goto_out;
 

diff --git a/lib/metadata/metadata-exported.h b/lib/metadata/metadata-exported.h
index 8c7bd4583db04d3a3d2573ac5d5f5cef8141c704..c9825799bb070d830c9cf64b66cd219ee4cdc642 100644 (file)
--- a/lib/metadata/metadata-exported.h
+++ b/lib/metadata/metadata-exported.h
@@ -1380,8 +1380,9 @@ int wipe_cache_pool(struct logical_volume *cache_pool_lv);
 struct lv_status_vdo {
        struct dm_pool *mem;
        struct dm_vdo_status *vdo;
-       uint64_t data_blocks_used;      /* grabbed from /sys/kvdo */
-       uint64_t logical_blocks_used;   /* grabbed from /sys/kvdo */
+       /* grabbed from DM stats message, /sys/block/dm-/vdo or /sys/kvdo */
+       uint64_t data_blocks_used;
+       uint64_t logical_blocks_used;
        dm_percent_t usage;
        dm_percent_t saving;
        dm_percent_t data_usage;

diff --git a/lib/metadata/vdo_manip.c b/lib/metadata/vdo_manip.c
index c8eebe55a297038d01ef4f84786952e9eba8132d..1ee39c6d70ad865feb95539d3c1fc457bcbfd23e 100644 (file)
--- a/lib/metadata/vdo_manip.c
+++ b/lib/metadata/vdo_manip.c
@@ -217,10 +217,12 @@ int parse_vdo_pool_status(struct dm_pool *mem, const struct logical_volume *vdo_
        status->vdo = result.status;
 
        if ((result.status->operating_mode == DM_VDO_MODE_NORMAL) &&
-           _sysfs_get_kvdo_value(dm_name, dminfo, "statistics/data_blocks_used",
-                                 &status->data_blocks_used) &&
-           _sysfs_get_kvdo_value(dm_name, dminfo, "statistics/logical_blocks_used",
-                                 &status->logical_blocks_used)) {
+            (status->data_blocks_used ||
+            _sysfs_get_kvdo_value(dm_name, dminfo, "statistics/data_blocks_used",
+                                  &status->data_blocks_used)) &&
+           (status->logical_blocks_used ||
+            _sysfs_get_kvdo_value(dm_name, dminfo, "statistics/logical_blocks_used",
+                                  &status->logical_blocks_used))) {
                status->usage = dm_make_percent(result.status->used_blocks,
                                                result.status->total_blocks);
                status->saving = dm_make_percent(status->logical_blocks_used - status->data_blocks_used,