[lvm-devel] master - toollib: Drop the pv_read optimisation.

[Petr Rockai]

Gitweb:        http://git.fedorahosted.org/git/?p=lvm2.git;a=commitdiff;h=7e685e6c70e5b738e5740b920e6080b9a13c2556
Commit:        7e685e6c70e5b738e5740b920e6080b9a13c2556
Parent:        e1a63905d14cc73352b905c70cb4084b7e521e33
Author:        Petr Rockai <prockai at redhat.com>
AuthorDate:    Tue Feb 19 00:12:30 2013 +0100
Committer:     Petr Rockai <prockai at redhat.com>
CommitterDate: Sun Nov 17 21:41:26 2013 +0100

toollib: Drop the pv_read optimisation.

Only reading a single PV works correctly only in very limited circumstances.
Moreover, we can't rely on the MDA available on the PV either, since it may be
out of date in some circumstances (until now, we believed that PVs that have an
empty MDA are always orphans, but this is not 100% reliable either).
---
 tools/toollib.c |   93 +++++++++++++++++++++++++++----------------------------
 1 files changed, 46 insertions(+), 47 deletions(-)

diff --git a/tools/toollib.c b/tools/toollib.c
index bc8b33c..127dd66 100644
--- a/tools/toollib.c
+++ b/tools/toollib.c
@@ -744,6 +744,8 @@ int process_each_pv_in_vg(struct cmd_context *cmd, struct volume_group *vg,
 static int _process_all_devs(struct cmd_context *cmd, void *handle,
 			     process_single_pv_fn_t process_single_pv)
 {
+	struct pv_list *pvl;
+	struct dm_list *pvslist;
 	struct physical_volume *pv;
 	struct physical_volume pv_dummy;
 	struct dev_iter *iter;
@@ -752,7 +754,8 @@ static int _process_all_devs(struct cmd_context *cmd, void *handle,
 	int ret_max = ECMD_PROCESSED;
 	int ret;
 
-	if (!scan_vgs_for_pvs(cmd, 1))
+	lvmcache_seed_infos_from_lvmetad(cmd);
+	if (!(pvslist = get_pvs(cmd)))
 		return_ECMD_FAILED;
 
 	if (!(iter = dev_iter_create(cmd->filter, 1))) {
@@ -760,20 +763,28 @@ static int _process_all_devs(struct cmd_context *cmd, void *handle,
 		return ECMD_FAILED;
 	}
 
-	while ((dev = dev_iter_get(iter))) {
+	while ((dev = dev_iter_get(iter)))
+	{
 		if (sigint_caught()) {
 			ret_max = ECMD_FAILED;
 			stack;
 			break;
 		}
 
-		if (!(pv = pv_read(cmd, dev_name(dev), 0, 0))) {
-			memset(&pv_dummy, 0, sizeof(pv_dummy));
-			dm_list_init(&pv_dummy.tags);
-			dm_list_init(&pv_dummy.segments);
-			pv_dummy.dev = dev;
-			pv = &pv_dummy;
-		}
+		memset(&pv_dummy, 0, sizeof(pv_dummy));
+		dm_list_init(&pv_dummy.tags);
+		dm_list_init(&pv_dummy.segments);
+		pv_dummy.dev = dev;
+		pv = &pv_dummy;
+
+		/* TODO use a device-indexed hash here */
+		dm_list_iterate_items(pvl, pvslist)
+			if (pvl->pv->dev == dev)
+				pv = pvl->pv;
+
+		ret = process_single_pv(cmd, NULL, pv, handle);
+
+		free_pv_fid(pv);
 
 		ret = process_single_pv(cmd, NULL, pv, handle);
 		if (ret > ret_max)
@@ -804,11 +815,11 @@ int process_each_pv(struct cmd_context *cmd, int argc, char **argv,
 
 	struct pv_list *pvl;
 	struct physical_volume *pv;
-	struct dm_list *pvslist, *vgnames;
+	struct dm_list *pvslist = NULL, *vgnames;
 	struct dm_list tags;
 	struct str_list *sll;
 	char *at_sign, *tagname;
-	int scanned = 0;
+	struct device *dev;
 
 	dm_list_init(&tags);
 
@@ -854,52 +865,36 @@ int process_each_pv(struct cmd_context *cmd, int argc, char **argv,
 				}
 				pv = pvl->pv;
 			} else {
-				if (!(pv = pv_read(cmd, argv[opt],
-						   1, scan_label_only))) {
-					log_error("Failed to read physical "
-						  "volume \"%s\"", argv[opt]);
+				if (!pvslist) {
+					lvmcache_seed_infos_from_lvmetad(cmd);
+					if (!(pvslist = get_pvs(cmd)))
+						goto bad;
+				}
+
+				if (!(dev = dev_cache_get(argv[opt], cmd->filter))) {
+					log_error("Failed to find device "
+						  "\"%s\"", argv[opt]);
 					ret_max = ECMD_FAILED;
 					continue;
 				}
 
-				/*
-				 * If a PV has no MDAs it may appear to be an
-				 * orphan until the metadata is read off
-				 * another PV in the same VG.  Detecting this
-				 * means checking every VG by scanning every
-				 * PV on the system.
-				 */
-				if (!scanned && is_orphan(pv) &&
-				    dm_list_empty(&pv->fid->metadata_areas_in_use)) {
-					if (!scan_label_only &&
-					    !scan_vgs_for_pvs(cmd, 1)) {
-						stack;
-						ret_max = ECMD_FAILED;
-						continue;
-					}
-					scanned = 1;
-					free_pv_fid(pv);
-					if (!(pv = pv_read(cmd, argv[opt],
-							   1,
-							   scan_label_only))) {
-						log_error("Failed to read "
-							  "physical volume "
-							  "\"%s\"", argv[opt]);
-						ret_max = ECMD_FAILED;
-						continue;
-					}
+				pv = NULL;
+				dm_list_iterate_items(pvl, pvslist)
+					if (pvl->pv->dev == dev)
+						pv = pvl->pv;
+
+				if (!pv) {
+					log_error("Failed to find physical volume "
+						  "\"%s\"", argv[opt]);
+					ret_max = ECMD_FAILED;
+					continue;
 				}
 			}
 
 			ret = process_single_pv(cmd, vg, pv, handle);
+
 			if (ret > ret_max)
 				ret_max = ret;
-			/*
-			 * Free PV only if we called pv_read before,
-			 * otherwise the PV structure is part of the VG.
-			 */
-			if (!vg)
-				free_pv_fid(pv);
 		}
 		if (!dm_list_empty(&tags) && (vgnames = get_vgnames(cmd, 1)) &&
 			   !dm_list_empty(vgnames)) {
@@ -954,6 +949,10 @@ int process_each_pv(struct cmd_context *cmd, int argc, char **argv,
 		}
 	}
 out:
+	if (pvslist)
+		dm_list_iterate_items(pvl, pvslist)
+			free_pv_fid(pvl->pv);
+
 	if (lock_global)
 		unlock_vg(cmd, VG_GLOBAL);
 	return ret_max;