From ed420fb6917162ed17af69a9a0ec9ae26e61e209 Mon Sep 17 00:00:00 2001 From: Peter Rajnoha Date: Thu, 19 Feb 2015 14:30:20 +0100 Subject: [PATCH] pvcreate: switch to "none" dev-ext source during pvcreate The dev ext source must be reset for the dev_cache_get call (which evaluates filters), not lvmcache_label_scan - so fix original commit 727c7ff85d448743f751bc5218e73c41314ed5f1. Also, add comments in _pvcreate_check fn explaining why refresh filter and rescan is needed and exactly in which situations. --- lib/metadata/metadata.c | 82 +++++++++++++++++++++++++++++------------ 1 file changed, 59 insertions(+), 23 deletions(-) diff --git a/lib/metadata/metadata.c b/lib/metadata/metadata.c index a4c3033d6..5acb2b4f9 100644 --- a/lib/metadata/metadata.c +++ b/lib/metadata/metadata.c @@ -1416,18 +1416,18 @@ int vg_split_mdas(struct cmd_context *cmd __attribute__((unused)), * 0 indicates we may not. */ static int _pvcreate_check(struct cmd_context *cmd, const char *name, - struct pvcreate_params *pp) + struct pvcreate_params *pp, int *wiped) { struct physical_volume *pv; struct device *dev; int r = 0; - int wiped; int scan_needed = 0; int filter_refresh_needed = 0; - dev_ext_t dev_ext_src = external_device_info_source(); /* FIXME Check partition type is LVM unless --force is given */ + *wiped = 0; + /* Is there a pv here already? */ pv = find_pv_by_name(cmd, name, 1, 1); @@ -1452,6 +1452,33 @@ static int _pvcreate_check(struct cmd_context *cmd, const char *name, dev = dev_cache_get(name, cmd->full_filter); + /* + * Refresh+rescan at the end is needed if: + * - we don't obtain device list from udev, + * hence persistent cache file is used + * and we need to trash it and reevaluate + * for any changes done outside - adding + * any new foreign signature which may affect + * filtering - before we do pvcreate, we + * need to be sure that we have up-to-date + * view for filters + * + * - we have wiped existing foreign signatures + * from dev as this may affect what's filtered + * as well + * + * + * Only rescan at the end is needed if: + * - we've just checked whether dev is fileterd + * by MD filter. We do the refresh in-situ, + * so no need to require the refresh at the + * end of this fn. This is to allow for + * wiping MD signature during pvcreate for + * the dev - the dev would normally be + * filtered because of MD filter. + * This is an exception. + */ + /* Is there an md superblock here? */ if (!dev && md_filtering()) { if (!refresh_filters(cmd)) @@ -1462,7 +1489,8 @@ static int _pvcreate_check(struct cmd_context *cmd, const char *name, init_md_filtering(1); scan_needed = 1; - } + } else if (!obtain_device_list_from_udev()) + filter_refresh_needed = scan_needed = 1; if (!dev) { log_error("Device %s not found (or ignored by filtering).", name); @@ -1481,26 +1509,13 @@ static int _pvcreate_check(struct cmd_context *cmd, const char *name, if (!wipe_known_signatures(cmd, dev, name, TYPE_LVM1_MEMBER | TYPE_LVM2_MEMBER, - 0, pp->yes, pp->force, &wiped)) { + 0, pp->yes, pp->force, wiped)) { log_error("Aborting pvcreate on %s.", name); goto out; } - if (wiped) { - if (dev_ext_src == DEV_EXT_UDEV) - /* - * wipe_known_signatures called later fires WATCH event - * to update udev database. But at the moment, we have - * no way to synchronize with such event - we may end - * up still seeing the old info in udev db and pvcreate - * can fail to proceed because of the device still - * being filtered (because of the stale info in udev db). - * Disable udev dev-ext source temporarily here for - * this reason. - */ - init_external_device_info_source(DEV_EXT_NONE); + if (wiped) filter_refresh_needed = scan_needed = 1; - } if (sigint_caught()) goto_out; @@ -1521,14 +1536,14 @@ out: r = 0; } - if (scan_needed) + if (scan_needed) { if (!lvmcache_label_scan(cmd, 2)) { stack; r = 0; } + } free_pv_fid(pv); - init_external_device_info_source(dev_ext_src); return r; } @@ -1637,9 +1652,11 @@ struct physical_volume *pvcreate_vol(struct cmd_context *cmd, const char *pv_nam { struct physical_volume *pv = NULL; struct device *dev; + int wiped = 0; struct dm_list mdas; struct pvcreate_params default_pp; char buffer[64] __attribute__((aligned(8))); + dev_ext_t dev_ext_src; pvcreate_params_set_defaults(&default_pp); if (!pp) @@ -1661,13 +1678,32 @@ struct physical_volume *pvcreate_vol(struct cmd_context *cmd, const char *pv_nam } } - if (!_pvcreate_check(cmd, pv_name, pp)) + if (!_pvcreate_check(cmd, pv_name, pp, &wiped)) goto_bad; if (sigint_caught()) goto_bad; - if (!(dev = dev_cache_get(pv_name, cmd->full_filter))) { + /* + * wipe_known_signatures called in _pvcreate_check fires + * WATCH event to update udev database. But at the moment, + * we have no way to synchronize with such event - we may + * end up still seeing the old info in udev db and pvcreate + * can fail to proceed because of the device still being + * filtered (because of the stale info in udev db). + * Disable udev dev-ext source temporarily here for + * this reason and rescan with DEV_EXT_NONE dev-ext + * source (so filters use DEV_EXT_NONE source). + */ + dev_ext_src = external_device_info_source(); + if (wiped && (dev_ext_src == DEV_EXT_UDEV)) + init_external_device_info_source(DEV_EXT_NONE); + + dev = dev_cache_get(pv_name, cmd->full_filter); + + init_external_device_info_source(dev_ext_src); + + if (!dev) { log_error("%s: Couldn't find device. Check your filters?", pv_name); goto bad;