[lvm-devel] main - vgchange: move autoactivation setup code
David Teigland
teigland at sourceware.org
Wed Nov 10 23:39:16 UTC 2021
Gitweb: https://sourceware.org/git/?p=lvm2.git;a=commitdiff;h=92e741eda060b4712fab5b37e0bee2cc5e155a57
Commit: 92e741eda060b4712fab5b37e0bee2cc5e155a57
Parent: d608837b2a88d0ed0c7ef7d8e6135e2d37687ff1
Author: David Teigland <teigland at redhat.com>
AuthorDate: Wed Nov 10 14:44:11 2021 -0600
Committer: David Teigland <teigland at redhat.com>
CommitterDate: Wed Nov 10 14:44:11 2021 -0600
vgchange: move autoactivation setup code
into its own function, no functional change.
---
tools/vgchange.c | 159 +++++++++++++++++++++++++++++++++++--------------------
1 file changed, 102 insertions(+), 57 deletions(-)
diff --git a/tools/vgchange.c b/tools/vgchange.c
index acdde97a8..bbb565643 100644
--- a/tools/vgchange.c
+++ b/tools/vgchange.c
@@ -735,12 +735,18 @@ static int _vgchange_single(struct cmd_context *cmd, const char *vg_name,
return ret;
}
-static int _check_autoactivation(struct cmd_context *cmd, struct vgchange_params *vp, int *skip_command)
+static int _vgchange_autoactivation_setup(struct cmd_context *cmd,
+ struct vgchange_params *vp,
+ int *skip_command,
+ const char **vgname_ret,
+ uint32_t *flags)
{
const char *aa;
+ char *vgname = NULL;
+ int found_none = 0, found_all = 0, found_incomplete = 0;
if (!(aa = arg_str_value(cmd, autoactivation_ARG, NULL)))
- return 1;
+ return_0;
if (strcmp(aa, "event")) {
log_print("Skip vgchange for unknown autoactivation value.");
@@ -755,9 +761,99 @@ static int _check_autoactivation(struct cmd_context *cmd, struct vgchange_params
}
vp->vg_complete_to_activate = 1;
-
cmd->use_hints = 0;
+ get_single_vgname_cmd_arg(cmd, NULL, &vgname);
+
+ /*
+ * Special label scan optimized for autoactivation that is based on
+ * info read from /run/lvm/ files created by pvscan --cache during
+ * autoactivation. Add an option to disable this optimization? e.g.
+ * "online_skip" in --autoactivation / auto_activation_settings
+ *
+ * In some cases it might be useful to strictly follow the online
+ * files, and not fall back to a standard label scan when no pvs or
+ * incomplete pvs are found from the online files. Add option for
+ * that? e.g.
+ * "online_only" in --autoactivation / auto_activation_settings
+ *
+ * Generally the way that vgchange -aay --autoactivation event is
+ * currently used, it will not be called until pvscan --cache has found
+ * the VG is complete, so it will not generally be following the paths
+ * that fall back to standard label_scan.
+ *
+ * TODO: Like pvscan_aa_quick, this could do lock_vol(vgname) before
+ * label_scan_vg_online, then set cmd->can_use_one_scan=1 to avoid
+ * rescanning in _vg_read called by process_each_vg.
+ */
+
+ /*
+ * Perform label_scan on PVs that are online (per /run/lvm files)
+ * for the given VG (or when no VG name is given, all online PVs.)
+ * If this fails, the caller will do a normal process_each_vg without
+ * optimizations (which will do a full label_scan.)
+ */
+ if (!label_scan_vg_online(cmd, vgname, &found_none, &found_all, &found_incomplete)) {
+ log_print("PVs online error%s%s, using all devices.", vgname ? " for VG " : "", vgname ?: "");
+ return 1;
+ }
+
+ /*
+ * Not the expected usage, activate any VGs that are complete based on
+ * pvs_online. Only online pvs are used.
+ */
+ if (!vgname) {
+ *flags |= PROCESS_SKIP_SCAN;
+ return 1;
+ }
+
+ /*
+ * The expected and optimal usage, because the udev rule calls
+ * vgchange -aay --autoactivation event vgname when all PVs
+ * for vgname are found online. Only online pvs are used.
+ */
+ if (found_all) {
+ *flags |= PROCESS_SKIP_SCAN;
+ *vgname_ret = vgname;
+ return 1;
+ }
+
+ /*
+ * Possible option to only activate from only online pvs even if they
+ * are not all found, and not fall back to a full label_scan.
+ */
+ /*
+ if (online_only) {
+ log_print("PVs online %s.", found_none ? "not found" : "incomplete");
+ return vgname ? 0 : 1;
+ }
+ */
+
+ /*
+ * Not expected usage, no online pvs for the vgname were found. The
+ * caller will fall back to process_each doing a full label_scan to
+ * look for the VG. (No optimization used.)
+ */
+ if (found_none) {
+ log_print("PVs online not found for VG %s, using all devices.", vgname);
+ return 1;
+ }
+
+ /*
+ * Not expected usage, only some online pvs for the vgname were found.
+ * The caller will fall back to process_each doing a full label_scan to
+ * look for all PVs in the VG. (No optimization used.)
+ */
+ if (found_incomplete) {
+ log_print("PVs online incomplete for VG %s, using all devicess.", vgname);
+ return 1;
+ }
+
+ /*
+ * Shouldn't happen, the caller will fall back to standard
+ * process_each. (No optimization used.)
+ */
+ log_print("PVs online unknown for VG %s, using all devices.", vgname);
return 1;
}
@@ -765,7 +861,7 @@ int vgchange(struct cmd_context *cmd, int argc, char **argv)
{
struct vgchange_params vp = { 0 };
struct processing_handle *handle;
- char *vgname = NULL;
+ const char *vgname = NULL;
uint32_t flags = 0;
int ret;
@@ -879,62 +975,11 @@ int vgchange(struct cmd_context *cmd, int argc, char **argv)
}
if (arg_is_set(cmd, autoactivation_ARG)) {
- int found_none = 0, found_all = 0, found_incomplete = 0;
int skip_command = 0;
-
- if (!_check_autoactivation(cmd, &vp, &skip_command))
+ if (!_vgchange_autoactivation_setup(cmd, &vp, &skip_command, &vgname, &flags))
return ECMD_FAILED;
if (skip_command)
return ECMD_PROCESSED;
-
- /*
- * Special label scan optimized for autoactivation
- * that is based on info read from /run/lvm/ files
- * created by pvscan --cache during autoactivation.
- * Add an option to disable this optimization? e.g.
- * "online_skip" in --autoactivation / auto_activation_settings
- *
- * In some cases it might be useful to strictly follow
- * the online files, and not fall back to a standard
- * label scan when no pvs or incomplete pvs are found
- * from the online files. Add option for that? e.g.
- * "online_only" in --autoactivation / auto_activation_settings
- *
- * Generally the way that vgchange -aay --autoactivation event
- * is currently used, it will not be called until pvscan --cache
- * has found the VG is complete, so it will not generally be
- * following the paths that fall back to standard label_scan.
- *
- * TODO: Like pvscan_aa_quick, this could do lock_vol(vgname)
- * before label_scan_vg_online, then set cmd->can_use_one_scan=1
- * to avoid rescanning in _vg_read called by process_each_vg.
- */
- get_single_vgname_cmd_arg(cmd, NULL, &vgname);
- if (!label_scan_vg_online(cmd, vgname, &found_none, &found_all, &found_incomplete)) {
- log_print("PVs online error%s%s, using all devices.", vgname ? " for VG " : "", vgname ?: "");
- } else {
- if (!vgname) {
- /* Not expected usage, activate any VGs that are complete based on pvs_online. */
- flags |= PROCESS_SKIP_SCAN;
- } else if (found_all) {
- /* The expected and optimal usage, only online PVs are read. */
- flags |= PROCESS_SKIP_SCAN;
- /*
- } else if (online_only) {
- log_print("PVs online %s.", found_none ? "not found" : "incomplete");
- return vgname ? ECMD_FAILED : ECMD_PROCESSED;
- */
- } else if (found_none) {
- /* Not expected usage, use full label_scan in process_each */
- log_print("PVs online not found for VG %s, using all devices.", vgname);
- } else if (found_incomplete) {
- /* Not expected usage, use full label_scan in process_each */
- log_print("PVs online incomplete for VG %s, using all devicess.", vgname);
- } else {
- /* Shouldn't happen */
- log_print("PVs online unknown for VG %s, using all devices.", vgname);
- }
- }
}
if (update)
@@ -949,7 +994,7 @@ int vgchange(struct cmd_context *cmd, int argc, char **argv)
handle->custom_handle = &vp;
- ret = process_each_vg(cmd, argc, argv, NULL, NULL, flags, 0, handle, &_vgchange_single);
+ ret = process_each_vg(cmd, argc, argv, vgname, NULL, flags, 0, handle, &_vgchange_single);
destroy_processing_handle(cmd, handle);
return ret;
More information about the lvm-devel
mailing list