pvscan: recognize "pci" as a common symlink component in filters

In case the filter strings don't include "/dev/disk", and only
include "pci".

lib/commands/toolcontext.h

@@ -194,6 +194,7 @@ struct cmd_context {
 	unsigned create_edit_devices_file:1;	/* command expects to create and/or edit devices file */
 	unsigned edit_devices_file:1;		/* command expects to edit devices file */
 	unsigned filter_deviceid_skip:1;	/* don't use filter-deviceid */
+	unsigned filter_regex_skip:1;		/* don't use filter-regex */
 	unsigned filter_regex_with_devices_file:1; /* use filter-regex even when devices file is enabled */
 	unsigned filter_nodata_only:1;          /* only use filters that do not require data from the dev */
 	unsigned run_by_dmeventd:1;		/* command is being run by dmeventd */
@@ -207,6 +208,7 @@ struct cmd_context {
 	unsigned udevoutput:1;
 	unsigned online_vg_file_removed:1;
 	unsigned disable_dm_devs:1;		/* temporarily disable use of dm devs cache */
+	unsigned filter_regex_set_preferred_name_disable:1; /* prevent dev_set_preferred_name */
 
 	/*
 	 * Devices and filtering.

lib/filters/filter-regex.c

@@ -161,6 +161,9 @@ static int _accept_p(struct cmd_context *cmd, struct dev_filter *f, struct devic
 	if (cmd->enable_devices_list)
 		return 1;
 
+	if (cmd->filter_regex_skip)
+		return 1;
+
 	if (cmd->enable_devices_file && !cmd->filter_regex_with_devices_file) {
 		/* can't warn in create_filter because enable_devices_file is set later */
 		if (rf->config_filter && !rf->warned_filter) {
@@ -179,7 +182,7 @@ static int _accept_p(struct cmd_context *cmd, struct dev_filter *f, struct devic
 
 		if (m >= 0) {
 			if (dm_bit(rf->accept, m)) {
-				if (!first)
+				if (!first && !cmd->filter_regex_set_preferred_name_disable)
 					dev_set_preferred_name(sl, dev);
 
 				return 1;
@@ -250,3 +253,48 @@ struct dev_filter *regex_filter_create(const struct dm_config_value *patterns, i
 	dm_pool_destroy(mem);
 	return NULL;
 }
+
+static int _filter_contains_symlink(struct cmd_context *cmd, int filter_cfg)
+{
+	const struct dm_config_node *cn;
+	const struct dm_config_value *cv;
+	const char *fname;
+		
+	if ((cn = find_config_tree_array(cmd, filter_cfg, NULL))) {
+		for (cv = cn->v; cv; cv = cv->next) {
+			if (cv->type != DM_CFG_STRING)
+				continue;
+			if (!cv->v.str)
+				continue;
+			
+			fname = cv->v.str;
+		
+			if (fname[0] != 'a')
+				continue;
+	
+			if (strstr(fname, "/dev/disk/"))
+				return 1;
+			if (strstr(fname, "/dev/mapper/"))
+				return 1;
+		
+			/* In case /dev/disk/by was omitted */
+			if (strstr(fname, "lvm-pv-uuid"))
+				return 1;
+			if (strstr(fname, "dm-uuid"))
+				return 1;
+			if (strstr(fname, "wwn-"))
+				return 1;
+			if (strstr(fname, "pci-"))
+				return 1;
+		}
+	}
+
+	return 0;
+}
+
+int regex_filter_contains_symlink(struct cmd_context *cmd)
+{
+	return _filter_contains_symlink(cmd, devices_filter_CFG) ||
+	       _filter_contains_symlink(cmd, devices_global_filter_CFG);
+}
+

lib/filters/filter.h

@@ -64,4 +64,6 @@ struct dev_filter *usable_filter_create(struct cmd_context *cmd, struct dev_type
 #define DEV_FILTERED_DEVICES_LIST	0x00001000
 #define DEV_FILTERED_IS_LV		0x00002000
 
+int regex_filter_contains_symlink(struct cmd_context *cmd);
+
 #endif 	/* _LVM_FILTER_H */

lib/label/label.c

@@ -27,6 +27,7 @@
 #include "lib/format_text/layout.h"
 #include "lib/device/device_id.h"
 #include "lib/device/online.h"
+#include "lib/filters/filter.h"
 
 #include <sys/stat.h>
 #include <fcntl.h>
@@ -1099,6 +1100,20 @@ int label_scan_vg_online(struct cmd_context *cmd, const char *vgname,
 		log_debug("Skipping device_id filtering due to devname ids.");
 	}
 
+	/*
+	 * See corresponding code in pvscan.  This function is used during
+	 * startup autoactivation when udev has not created all symlinks, so
+	 * regex filter containing symlinks doesn't work.  pvscan has code
+	 * to properly check devs against the filter using DEVLINKS.  The
+	 * pvscan will only create pvs_online files for devs that pass the
+	 * filter.  We get devs from the pvs_online files, so we inherit the
+	 * regex filtering from pvscan and don't have to do it ourself.
+	 */
+	if (!cmd->enable_devices_file &&
+	    !cmd->enable_devices_list &&
+	    regex_filter_contains_symlink(cmd))
+		cmd->filter_regex_skip = 1;
+
 	cmd->filter_nodata_only = 1;
 
 	dm_list_iterate_items_safe(devl, devl2, &devs) {
@@ -1179,6 +1194,8 @@ int label_scan_vg_online(struct cmd_context *cmd, const char *vgname,
 	if (relax_deviceid_filter)
 		cmd->filter_deviceid_skip = 0;
 
+	cmd->filter_regex_skip = 0;
+
 	free_po_list(&pvs_online);
 
 	if (dm_list_empty(&devs)) {

tools/pvscan.c

@@ -803,49 +803,6 @@ out:
 	return ret;
 }
 
-/*
- * The optimization in which only the pvscan arg devname is added to dev-cache
- * does not work if there's an lvm.conf filter containing symlinks to the dev
- * like /dev/disk/by-id/lvm-pv-uuid-xyz entries.  A full dev_cache_scan will
- * associate the symlinks with the system dev name passed to pvscan, which lets
- * filter-regex match the devname with the symlink name in the filter.
- */
-static int _filter_uses_symlinks(struct cmd_context *cmd, int filter_cfg)
-{
-	const struct dm_config_node *cn;
-	const struct dm_config_value *cv;
-	const char *fname;
-
-	if ((cn = find_config_tree_array(cmd, filter_cfg, NULL))) {
-        	for (cv = cn->v; cv; cv = cv->next) {
-			if (cv->type != DM_CFG_STRING)
-				continue;
-			if (!cv->v.str)
-				continue;
-
-			fname = cv->v.str;
-
-			if (fname[0] != 'a')
-				continue;
-
-			if (strstr(fname, "/dev/disk/"))
-				return 1;
-			if (strstr(fname, "/dev/mapper/"))
-				return 1;
-
-			/* In case /dev/disk/by was omitted */
-			if (strstr(fname, "lvm-pv-uuid"))
-				return 1;
-			if (strstr(fname, "dm-uuid"))
-				return 1;
-			if (strstr(fname, "wwn-"))
-				return 1;
-		}
-	}
-
-	return 0;
-}
-
 struct pvscan_arg {
 	struct dm_list list;
 	const char *devname;
@@ -910,30 +867,6 @@ static int _get_args_devs(struct cmd_context *cmd, struct dm_list *pvscan_args,
 	struct pvscan_arg *arg;
 	struct device_list *devl;
 
-	/*
-	 * If no devices file is used, and lvm.conf filter is set to
-	 * accept /dev/disk/by-id/lvm-pv-uuid-xyz or another symlink,
-	 * but pvscan --cache is passed devname or major:minor, so
-	 * pvscan needs to match its arg device to the filter symlink.
-	 * setup_dev_in_dev_cache() adds /dev/sda2 to dev-cache which
-	 * does not match a symlink to /dev/sda2, so we need a full
-	 * dev_cache_scan that will associate all symlinks to sda2,
-	 * which allows filter-regex to work.  This case could be
-	 * optimized if needed by adding dev-cache entries for each
-	 * filter "a" entry (filter symlink patterns would still need
-	 * a full dev_cache_scan.)
-	 * (When no devices file is used and 69-dm-lvm.rules is
-	 * used which calls pvscan directly, symlinks may not
-	 * have been created by other rules when pvscan runs, so
-	 * the full dev_cache_scan may still not find them.)
-	 */
-	if (!cmd->enable_devices_file && !cmd->enable_devices_list &&
-	    (_filter_uses_symlinks(cmd, devices_filter_CFG) ||
-	     _filter_uses_symlinks(cmd, devices_global_filter_CFG))) {
-		log_print_pvscan(cmd, "finding all devices for filter symlinks.");
-		dev_cache_scan(cmd);
-	}
-
 	/* pass NULL filter when getting devs from dev-cache, filtering is done separately */
 
 	/* in common usage, no dev will be found for a devno */
@@ -1550,6 +1483,42 @@ static int _pvscan_cache_args(struct cmd_context *cmd, int argc, char **argv,
 
 	cmd->filter_nodata_only = 1;
 
+	/*
+	 * Hack to handle regex filter that contains a symlink name for dev arg.
+	 * pvscan --cache <dev> is called by our udev rule at a time when the
+	 * symlinks for <dev> may not all be created yet (by other udev rules.)
+	 * The regex filter in lvm.conf may refer to <dev> using a symlink name,
+	 * so we need to know all the symlinks for <dev> in order for the filter
+	 * to work correctly. Scanning /dev with dev_cache_scan() would usually
+	 * find all the symlink names for <dev>, adding them to dev->aliases,
+	 * which would let the filter work, but all symlinks aren't created yet.
+	 * But, the DEVLINKS env var, set by udev, contains all the symlink
+	 * names for <dev> that have been or *will be* created. So, we add all
+	 * these symlink names to dev->aliases, as if we had found them in /dev.
+	 * This allows <dev> to be recognized by a regex filter containing a
+	 * symlink for <dev>. We have to tell filter-regex to not set the
+	 * preferred name for <dev> to a symlink name since the <dev> may not
+	 * be usable by that symlink name yet.
+	 */
+	if ((dm_list_size(&pvscan_devs) == 1) &&
+	    !cmd->enable_devices_file &&
+	    !cmd->enable_devices_list &&
+	    regex_filter_contains_symlink(cmd)) {
+		char *env_str;
+		struct dm_list *env_aliases;
+		devl = dm_list_item(dm_list_first(&pvscan_devs), struct device_list);
+		if ((env_str = getenv("DEVLINKS"))) {
+			log_debug("Finding symlink names from DEVLINKS for filter regex.");
+			log_debug("DEVLINKS %s", env_str);
+			env_aliases = str_to_str_list(cmd->mem, env_str, " ", 0);
+			dm_list_splice(&devl->dev->aliases, env_aliases);
+		} else {
+			log_debug("Finding symlink names from /dev for filter regex.");
+			dev_cache_scan(cmd);
+		}
+		cmd->filter_regex_set_preferred_name_disable = 1;
+	}
+
 	dm_list_iterate_items_safe(devl, devl2, &pvscan_devs) {
 		if (!cmd->filter->passes_filter(cmd, cmd->filter, devl->dev, NULL)) {
 			log_print_pvscan(cmd, "%s excluded: %s.",

tools/vgchange.c

@@ -16,6 +16,7 @@
 #include "tools.h"
 #include "lib/device/device_id.h"
 #include "lib/label/hints.h"
+#include "lib/filters/filter.h"
 
 struct vgchange_params {
 	int lock_start_count;