From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Wysochanski Date: Mon, 23 Apr 2007 18:04:14 -0400 Subject: [REPOST PATCH 1/2] Add pvck ability to scan for labels on any area of disk In-Reply-To: <1177091131.11574.13.camel@linux-cxyg> References: <1177091131.11574.13.camel@linux-cxyg> Message-ID: <1177365854.4165.44.camel@linux-cxyg> List-Id: To: lvm-devel@redhat.com MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit I think all comments incorporated / addressed. Update pvck to read labels on disk, with flexible --labelsector parameter. Index: LVM2-label-read/lib/metadata/metadata.c =================================================================== --- LVM2-label-read.orig/lib/metadata/metadata.c 2007-04-23 14:21:01.000000000 -0400 +++ LVM2-label-read/lib/metadata/metadata.c 2007-04-23 17:53:02.000000000 -0400 @@ -1555,3 +1555,35 @@ int pv_write_orphan(struct cmd_context * return 1; } +/* + * Returns: + * 0 - fail + * 1 - success + */ +int pv_analyze(struct cmd_context *cmd, const char *pv_name, + int64_t label_sector) +{ + struct label *label; + struct device *dev; + + dev = dev_cache_get(pv_name, cmd->filter); + if (!dev) { + log_error("Device %s not found (or ignored by filtering).", + pv_name); + return 0; + } + + /* + * First, scan for LVM labels. + */ + if (!label_read(dev, &label, label_sector)) { + log_error("Could not find LVM label on %s", + pv_name); + return 0; + } + + log_print("Found label on %s, sector %"PRIu64", type=%s", + pv_name, label->sector, label->type); + + return 1; +} Index: LVM2-label-read/lib/metadata/metadata.h =================================================================== --- LVM2-label-read.orig/lib/metadata/metadata.h 2007-03-23 08:43:17.000000000 -0400 +++ LVM2-label-read/lib/metadata/metadata.h 2007-04-23 15:13:43.000000000 -0400 @@ -443,6 +443,8 @@ struct physical_volume *pv_create(const uint64_t pvmetadatasize, struct list *mdas); int pv_resize(struct physical_volume *pv, struct volume_group *vg, uint32_t new_pe_count); +int pv_analyze(struct cmd_context *cmd, const char *pv_name, + int64_t label_sector); struct volume_group *vg_create(struct cmd_context *cmd, const char *name, uint32_t extent_size, uint32_t max_pv, Index: LVM2-label-read/man/pvck.8 =================================================================== --- LVM2-label-read.orig/man/pvck.8 2007-03-30 17:00:25.000000000 -0400 +++ LVM2-label-read/man/pvck.8 2007-04-23 17:31:28.000000000 -0400 @@ -3,11 +3,29 @@ pvck \- check physical volume metadata .SH SYNOPSIS .B pvck -[\-d/\-\-debug] [\-h/\-?/\-\-help] [\-v/\-\-verbose] [PhysicalVolume...] +.RB [ \-d | \-\-debug ] +.RB [ \-h | \-\-help ] +.RB [ \-v | \-\-verbose ] +.RB [ \-\-labelsector ] +.IR PhysicalVolume " [" PhysicalVolume ...] .SH DESCRIPTION pvck checks physical volume LVM metadata for consistency. .SH OPTIONS See \fBlvm\fP for common options. +.TP +.BR \-\-labelsector " sector" +By default, 4 sectors of \fBPhysicalVolume\fP are scanned for an LVM label, +starting at sector 0. This parameter allows you to specify a different +starting sector for the scan and is useful for recovery situations. For +example, suppose the partition table is corrupted or lost on /dev/sda, +but you suspect there was an LVM partition at approximately 100 MB. This +area of the disk may be scanned by using the \fB--labelsector\fP parameter +with a value of 204800 (100 * 1024 * 1024 / 512 = 204800): +.sp +.BI "pvck --labelsector 204800 /dev/sda" +.sp +Note that a script can be used with \fB--labelsector\fP to automate the +process of finding LVM labels. .SH SEE ALSO .BR lvm (8), .BR pvcreate (8), Index: LVM2-label-read/tools/commands.h =================================================================== --- LVM2-label-read.orig/tools/commands.h 2007-03-30 17:00:26.000000000 -0400 +++ LVM2-label-read/tools/commands.h 2007-04-23 17:57:03.000000000 -0400 @@ -412,9 +412,12 @@ xx(pvck, "pvck " "\t[-d|--debug]\n" "\t[-h|--help]\n" + "\t[--labelsector sector] " "\n" "\t[-v|--verbose]\n" "\t[--version]" "\n" - "\tPhysicalVolume [PhysicalVolume...]\n" ) + "\tPhysicalVolume [PhysicalVolume...]\n", + + labelsector_ARG) xx(pvcreate, "Initialize physical volume(s) for use by LVM", Index: LVM2-label-read/tools/pvck.c =================================================================== --- LVM2-label-read.orig/tools/pvck.c 2007-03-30 17:00:26.000000000 -0400 +++ LVM2-label-read/tools/pvck.c 2007-04-23 17:33:00.000000000 -0400 @@ -15,16 +15,26 @@ #include "tools.h" -static int _pvck_single(struct cmd_context * cmd, - struct volume_group * vg, - struct physical_volume * pv, - void *handle) -{ - return ECMD_PROCESSED; -} - int pvck(struct cmd_context *cmd, int argc, char **argv) { - /* FIXME: Correlate findings of each PV */ - return process_each_pv(cmd, argc, argv, NULL, NULL, _pvck_single); + int i; + + /* FIXME: validate cmdline options */ + /* FIXME: what does the cmdline look like? */ + /* + * Use what's on the cmdline directly, and avoid calling into + * some of the other infrastructure functions, so as to avoid + * hitting some of the lvmcache behavior, scanning other devices, + * etc. + */ + for (i = 0; i < argc; i++) { + /* FIXME: warning and/or check if in use? */ + log_verbose("Scanning %s", argv[i]); + + pv_analyze(cmd, argv[i], + arg_int64_value(cmd, labelsector_ARG, + UINT64_C(0))); + } + + return ECMD_PROCESSED; }