From: Stefan Bader <stefan.bader@canonical.com>
Date: Mon, 13 Jan 2014 14:39:29 +0100
Subject: Convert dmraid to use dm-raid module for RAID4 and RAID5

The dmraid library used the dm-raid45 target for RAID4 and RAID5 sets.
This module however was never upstream and is suffering constant issues
when the Linux kernel changes.
Upstream introduced the dm-raid/raid module/target in 2.6.38. This can be
used to create device-mapper targets which use the MD RAID disciplines
(though not showing up in /proc/mdstat).

Most of the table constructor arguments can be mapped, only the member
devices may not have an offset.

From the old code it seems that RAID5 would always be build by set
elements which will not have an offset. So potentially only RAID4
could cause issues. That could be worked around if needed by creating
additional linear mappings.

NOTE: The event code is only compile tested. But we seem to have never
shipped the dmraid event tool which is needed to use this feature. And
we are about to remove support for ISW from dmraid (in favour of mdadm)
anyway.

Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

Index: dmraid-1.0.0.rc16/1.0.0.rc16/lib/activate/activate.c
===================================================================
--- dmraid-1.0.0.rc16.orig/1.0.0.rc16/lib/activate/activate.c	2014-01-14 15:41:29.872372693 +0100
+++ dmraid-1.0.0.rc16/1.0.0.rc16/lib/activate/activate.c	2014-01-14 15:41:59.692518476 +0100
@@ -118,6 +118,17 @@ _dm_path_offset(struct lib_context *lc,
 		     valid ? path : lc->path.error, offset);
 }
 
+/* Push metadata and data device path onto a table */
+static int
+_dm_meta_data_path(struct lib_context *lc, char **table, int valid,
+		   const char *meta, const char *path)
+
+{
+	return p_fmt(lc, table, " %s %s",
+		     meta ? meta : "-",
+		     valid ? path : lc->path.error);
+}
+
 /*
  * Create dm table for linear mapping.
  */
@@ -537,9 +548,10 @@ err:
 /* Push begin of line onto a RAID5 table. */
 /* FIXME: persistent dirty log. */
 static int
-_dm_raid45_bol(struct lib_context *lc, char **table, struct raid_set *rs,
+_dm_raid_bol(struct lib_context *lc, char **table, struct raid_set *rs,
 	       uint64_t sectors, unsigned int members)
 {
+	int rc;
 	int need_sync = rs_need_sync(rs);
 	struct handler_info rebuild_drive;
 
@@ -548,13 +560,31 @@ _dm_raid45_bol(struct lib_context *lc, c
 	if (need_sync && !get_rebuild_drive(lc, rs, &rebuild_drive))
 		return 0;
 
-	return p_fmt(lc, table, "0 %U %s core 2 %u %s %s 1 %u %u %d",
-		     sectors, get_dm_type(lc, rs->type),
-		     calc_region_size(lc,
-				      total_sectors(lc, rs) /
-				      _dm_raid_devs(lc, rs, 0)),
-		     (need_sync) ? "sync" : "nosync", get_type(lc, rs->type),
-		     rs->stride, members, rebuild_drive.data.i32);
+	if (rebuild_drive.data.i32 < 0) {
+		rc = p_fmt(lc, table,
+		           "0 %U %s %s 4 %u %s region_size %u %u",
+			   sectors,
+			   get_dm_type(lc, rs->type),
+			   get_type(lc, rs->type),
+			   rs->stride,
+			   (need_sync) ? "sync" : "nosync",
+			   calc_region_size(lc, total_sectors(lc, rs) /
+					    _dm_raid_devs(lc, rs, 0)),
+			   members);
+	} else {
+		rc = p_fmt(lc, table,
+			   "0 %U %s %s 6 %u %s rebuild %d region_size %u %u",
+			   sectors,
+			   get_dm_type(lc, rs->type),
+			   get_type(lc, rs->type),
+			   rs->stride,
+			   (need_sync) ? "sync" : "nosync",
+			   rebuild_drive.data.i32,
+			   calc_region_size(lc, total_sectors(lc, rs) /
+					    _dm_raid_devs(lc, rs, 0)),
+			   members);
+	}
+	return rc;
 }
 
 /* Create "error target" name based on raid set name. */
@@ -669,7 +699,7 @@ err:
 }
 
 static int
-dm_raid45(struct lib_context *lc, char **table, struct raid_set *rs)
+dm_raid(struct lib_context *lc, char **table, struct raid_set *rs)
 {
 	int ret;
 	uint64_t sectors = 0;
@@ -749,7 +779,7 @@ dm_raid45(struct lib_context *lc, char *
 	 */
 	sectors *= members - 1;
 
-	if (!_dm_raid45_bol(lc, table, rs, sectors, members))
+	if (!_dm_raid_bol(lc, table, rs, sectors, members))
 		goto err;
 
 	/* Stacked RAID sets (for RAID50 etc.) */
@@ -759,7 +789,8 @@ dm_raid45(struct lib_context *lc, char *
 		if (!(path = mkdm_path(lc, r->name)))
 			goto err;
 
-		ret = _dm_path_offset(lc, table, valid_rs(r), path, 0);
+		log_dbg(lc, "%s: raid set device %s", __func__, path);
+		ret = _dm_meta_data_path(lc, table, valid_rs(r), NULL, path);
 		dbg_free(path);
 
 		if (!ret)
@@ -768,8 +799,11 @@ dm_raid45(struct lib_context *lc, char *
 
 	/* Lowest level RAID devices. */
 	list_for_each_entry(rd, &rs->devs, devs) {
-		if (!_dm_path_offset(lc, table, valid_rd(rd), 
-				     rd->di->path, rd->offset))
+		if (rd->offset)
+			goto err;
+		log_dbg(lc, "%s: low level dev %s", __func__, rd->di->path);
+		if (!_dm_meta_data_path(lc, table, valid_rd(rd), NULL,
+					rd->di->path))
 			goto err;
 	}
 
@@ -802,11 +836,11 @@ static struct type_handler {
 	{ t_linear, dm_linear },
 	{ t_raid0, dm_raid0 },
 	{ t_raid1, dm_raid1 },
-	{ t_raid4, dm_raid45 },
-	{ t_raid5_ls, dm_raid45 },
-	{ t_raid5_rs, dm_raid45 },
-	{ t_raid5_la, dm_raid45 },
-	{ t_raid5_ra, dm_raid45 },
+	{ t_raid4, dm_raid },
+	{ t_raid5_ls, dm_raid },
+	{ t_raid5_rs, dm_raid },
+	{ t_raid5_la, dm_raid },
+	{ t_raid5_ra, dm_raid },
 	/* RAID types below not supported (yet) */
 	{ t_raid6, dm_unsup },
 };
Index: dmraid-1.0.0.rc16/1.0.0.rc16/lib/metadata/metadata.c
===================================================================
--- dmraid-1.0.0.rc16.orig/1.0.0.rc16/lib/metadata/metadata.c	2014-01-14 15:41:29.908372863 +0100
+++ dmraid-1.0.0.rc16/1.0.0.rc16/lib/metadata/metadata.c	2014-01-14 15:41:59.692518476 +0100
@@ -31,11 +31,11 @@ static const struct {
 	{ t_linear, "linear", "linear"},
 	{ t_raid0, "stripe", "striped"},
 	{ t_raid1, "mirror", "mirror"},
-	{ t_raid4, "raid4", "raid45"},
-	{ t_raid5_ls, "raid5_ls", "raid45"},
-	{ t_raid5_rs, "raid5_rs", "raid45"},
-	{ t_raid5_la, "raid5_la", "raid45"},
-	{ t_raid5_ra, "raid5_ra", "raid45"},
+	{ t_raid4, "raid4", "raid"},
+	{ t_raid5_ls, "raid5_ls", "raid"},
+	{ t_raid5_rs, "raid5_rs", "raid"},
+	{ t_raid5_la, "raid5_la", "raid"},
+	{ t_raid5_ra, "raid5_ra", "raid"},
 	{ t_raid6, "raid6", NULL},
 };
 
Index: dmraid-1.0.0.rc16/1.0.0.rc16/lib/events/libdmraid-events-isw.c
===================================================================
--- dmraid-1.0.0.rc16.orig/1.0.0.rc16/lib/events/libdmraid-events-isw.c	2014-01-14 10:20:23.598184676 +0100
+++ dmraid-1.0.0.rc16/1.0.0.rc16/lib/events/libdmraid-events-isw.c	2014-01-14 15:41:59.696518490 +0100
@@ -502,7 +502,7 @@ static int _get_num_devs_from_status(cha
 	int ret;
 
 	for (ret = 0; *status; status++) {
-		if (*status == 'A' || *status == 'D')
+		if (*status == 'A' || *status == 'a' || *status == 'D')
 			ret++;
 	}
 
@@ -1258,8 +1258,8 @@ err:
 	return D_IGNORE;
 }
 
-/* Get the raid45 device(s) that caused the trigger. */
-static enum disk_state_type _process_raid45_event(struct dm_task *dmt,
+/* Get the raid device(s) that caused the trigger. */
+static enum disk_state_type _process_raid_event(struct dm_task *dmt,
 						  char *params)
 {
 	int argc, i, num_devs, dead, ret = D_INSYNC;
@@ -1272,32 +1272,34 @@ static enum disk_state_type _process_rai
 		return D_IGNORE;
 
 	/*
-	 * dm core parms (NOT provided in @params):  	0 976783872 raid45 
-	 *
-	 * raid45 device parms:     	3 253:4 253:5 253:6
-	 * raid45 device status:	1 AAA
+	 * raid device status:	<type> 3 AAA <synced/total> <action> <rmm>
 	 */
 
+	/* Skip over the raid type */
+	if(!dm_split_words(params, 1, 0, &p))
+		goto err;
+	p += strlen(p) + 1;
+
 	/* Number of devices. */
 	num_devs = _get_num_devs(params, &p);
 	if (!num_devs)
 		goto err;
 
-	/* Devices names + "1" + "AA". */
-	argc = num_devs + 2;
+	/* AAA + <completeness> <action> <resync mismatches> */
+	argc = 4;
 	args = dm_malloc(argc * sizeof(*args));
 	if (!args ||
 	    dm_split_words(p, argc, 0, args) != argc)
 		goto err;
 
-	dev_status_str = args[num_devs + 1];
+	dev_status_str = args[0];
 
 	/* Consistency check on num_devs and status chars. */
 	i = _get_num_devs_from_status(dev_status_str);
 	if (i != num_devs)
 		goto err;
 
-	/* Check for bad raid45 devices. */
+	/* Check for bad raid devices. */
 	for (i = 0, p = dev_status_str; i < rs->num_devs; i++) {
 		/* Skip past any non active/dead identifiers. */
 		dead = *(p++) == 'D';
@@ -1324,7 +1326,7 @@ static enum disk_state_type _process_rai
 	return ret;
 
 err:
-	_event_cleanup_and_log(args, "raid45");
+	_event_cleanup_and_log(args, "raid");
 	return D_IGNORE;
 }
 
@@ -1341,7 +1343,7 @@ static void _process_event(char *target_
 	} *proc,  process[] = {
 		{ "striped", _process_stripe_event, 0 },
 		{ "mirror",  _process_mirror_event, 1 },
-		{ "raid45",  _process_raid45_event, 1 },
+		{ "raid",    _process_raid_event, 1 },
 	};
 #ifdef	_LIBDMRAID_DSO_TESTING
 	struct dso_raid_set *rs;
@@ -1352,7 +1354,7 @@ static void _process_event(char *target_
 	 * stripe (raid 0),
 	 * mirror (raid 1)
 	 * or
-	 * raid45 (raid 4/5).
+	 * raid   (raid 4/5).
 	 */
 	for (proc = process; proc < ARRAY_END(process); proc++) {
 		if (!strcmp(target_type, proc->target_type))