Add mbr pseudo metadata handler.

To support incorpating a new bare device into a collection of arrays -
one partition each - mdadm needs a modest understanding of partition
tables.
The main needs to be able to recognise a partition table on one device
and copy it onto another.

This will be done using pseudo metadata types 'mbr' and 'gpt'.

Signed-off-by: NeilBrown <neilb@suse.de>

9 files changed, 342 insertions, 78 deletions

diff --git a/Assemble.c b/Assemble.c
index 42f71fd4..23d0b826 100644
--- a/Assemble.c
+++ b/Assemble.c
@@ -262,8 +262,14 @@ int Assemble(struct supertype *st, char *mddev,
 			tmpdev->used = 2;
 		} else if (tst->ss->load_super(tst,dfd, NULL)) {
 			if (report_missmatch)
-				fprintf( stderr, Name ": no RAID superblock on %s\n",
-					 devname);
+				fprintf(stderr, Name ": no RAID superblock on %s\n",
+					devname);
+		} else if (tst->ss->compare_super == NULL) {
+			if (report_missmatch)
+				fprintf(stderr, Name ": Cannot assemble %s metadata on %s\n",
+					tst->ss->name, devname);
+			tst->ss->free_super(tst);
+			tmpdev->used = 2;
 		} else if (auto_assem && st == NULL &&
 			   !conf_test_metadata(tst->ss->name,
 					       tst->ss->match_home(tst, homehost) == 1)) {
diff --git a/Examine.c b/Examine.c
index 7fbd4ae2..01838c8b 100644
--- a/Examine.c
+++ b/Examine.c
@@ -100,7 +100,11 @@ int Examine(mddev_dev_t devlist, int brief, int export, int scan,
 					     devlist->devname, 0, 0, NULL);
 		/* Ok, its good enough to try, though the checksum could be wrong */
 
-		if (brief) {
+		if (brief && st->ss->brief_examine_super == NULL) {
+			if (!scan)
+				fprintf(stderr, Name ": No brief listing for %s on %s\n",
+					st->ss->name, devlist->devname);
+		} else if (brief) {
 			struct array *ap;
 			char *d;
 			for (ap=arrays; ap; ap=ap->next) {
diff --git a/Incremental.c b/Incremental.c
index fe6aad28..bcbd78d0 100644
--- a/Incremental.c
+++ b/Incremental.c
@@ -142,11 +142,13 @@ int Incremental(char *devname, int verbose, int runstop,
 		rv = try_spare(devname, &dfd, policy, st, verbose);
 		goto out;
 	}
-	if (st->ss->load_super(st, dfd, NULL)) {
+	if (st->ss->compare_super == NULL ||
+	    st->ss->load_super(st, dfd, NULL)) {
 		if (verbose >= 0)
 			fprintf(stderr, Name ": no RAID superblock on %s.\n",
 				devname);
 		rv = try_spare(devname, &dfd, policy, st, verbose);
+		free(st);
 		goto out;
 	}
 	close (dfd); dfd = -1;
diff --git a/Kill.c b/Kill.c
index 3d1810f0..f5c30e97 100644
--- a/Kill.c
+++ b/Kill.c
@@ -53,7 +53,7 @@ int Kill(char *dev, struct supertype *st, int force, int quiet, int noexcl)
 	}
 	if (st == NULL)
 		st = guess_super(fd);
-	if (st == NULL) {
+	if (st == NULL || st->ss->init_super == NULL) {
 		if (!quiet)
 			fprintf(stderr, Name ": Unrecognised md component device - %s\n", dev);
 		close(fd);
diff --git a/Makefile b/Makefile
index af9804c5..75a8a413 100644
--- a/Makefile
+++ b/Makefile
@@ -99,6 +99,7 @@ OBJS =  mdadm.o config.o policy.o mdstat.o  ReadMe.o util.o Manage.o Assemble.o
 	Create.o Detail.o Examine.o Grow.o Monitor.o dlink.o Kill.o Query.o \
 	Incremental.o \
 	mdopen.o super0.o super1.o super-ddf.o super-intel.o bitmap.o \
+	super-mbr.o \
 	restripe.o sysfs.o sha1.o mapfile.o crc32.o sg_io.o msg.o \
 	platform-intel.o probe_roms.o
 
@@ -106,16 +107,21 @@ SRCS =  mdadm.c config.c policy.c mdstat.c  ReadMe.c util.c Manage.c Assemble.c
 	Create.c Detail.c Examine.c Grow.c Monitor.c dlink.c Kill.c Query.c \
 	Incremental.c \
 	mdopen.c super0.c super1.c super-ddf.c super-intel.c bitmap.c \
+	super-mbr.c \
 	restripe.c sysfs.c sha1.c mapfile.c crc32.c sg_io.c msg.c \
 	platform-intel.c probe_roms.c
 
+INCL = mdadm.h part.h bitmap.h
+
 MON_OBJS = mdmon.o monitor.o managemon.o util.o mdstat.o sysfs.o config.o policy.o \
 	Kill.o sg_io.o dlink.o ReadMe.o super0.o super1.o super-intel.o \
+	super-mbr.o \
 	super-ddf.o sha1.o crc32.o msg.o bitmap.o \
 	platform-intel.o probe_roms.o
 
 MON_SRCS = mdmon.c monitor.c managemon.c util.c mdstat.c sysfs.c config.c policy.c \
 	Kill.c sg_io.c dlink.c ReadMe.c super0.c super1.c super-intel.c \
+	super-mbr.c \
 	super-ddf.c sha1.c crc32.c msg.c bitmap.c \
 	platform-intel.c probe_roms.c
 
@@ -124,7 +130,7 @@ STATICOBJS = pwgr.o
 
 ASSEMBLE_SRCS := mdassemble.c Assemble.c Manage.c config.c policy.c dlink.c util.c \
 	super0.c super1.c super-ddf.c super-intel.c sha1.c crc32.c sg_io.c mdstat.c \
-	platform-intel.c probe_roms.c sysfs.c
+	platform-intel.c probe_roms.c sysfs.c super-mbr.c
 ASSEMBLE_AUTO_SRCS := mdopen.c
 ASSEMBLE_FLAGS:= $(CFLAGS) -DMDASSEMBLE
 ifdef MDASSEMBLE_AUTO
@@ -149,20 +155,20 @@ mdadm : $(OBJS)
 mdadm.static : $(OBJS) $(STATICOBJS)
 	$(CC) $(LDFLAGS) -static -o mdadm.static $(OBJS) $(STATICOBJS)
 
-mdadm.tcc : $(SRCS) mdadm.h
+mdadm.tcc : $(SRCS) $(INCL)
 	$(TCC) -o mdadm.tcc $(SRCS)
 
-mdadm.klibc : $(SRCS) mdadm.h
+mdadm.klibc : $(SRCS) $(INCL)
 	rm -f $(OBJS) 
 	$(CC) -nostdinc -iwithprefix include -I$(KLIBC)/klibc/include -I$(KLIBC)/linux/include -I$(KLIBC)/klibc/arch/i386/include -I$(KLIBC)/klibc/include/bits32 $(CFLAGS) $(SRCS)
 
-mdadm.Os : $(SRCS) mdadm.h
+mdadm.Os : $(SRCS) $(INCL)
 	$(CC) -o mdadm.Os $(CFLAGS) $(LDFLAGS) -DHAVE_STDINT_H -Os $(SRCS)
 
-mdadm.O2 : $(SRCS) mdadm.h mdmon.O2
+mdadm.O2 : $(SRCS) $(INCL) mdmon.O2
 	$(CC) -o mdadm.O2 $(CFLAGS) $(LDFLAGS) -DHAVE_STDINT_H -O2 -D_FORTIFY_SOURCE=2 $(SRCS)
 
-mdmon.O2 : $(MON_SRCS) mdadm.h mdmon.h
+mdmon.O2 : $(MON_SRCS) $(INCL) mdmon.h
 	$(CC) -o mdmon.O2 $(CFLAGS) $(LDFLAGS) $(MON_LDFLAGS) -DHAVE_STDINT_H -O2 -D_FORTIFY_SOURCE=2 $(MON_SRCS)
 
 # use '-z now' to guarantee no dynamic linker interactions with the monitor thread
@@ -173,25 +179,25 @@ msg.o: msg.c msg.h
 test_stripe : restripe.c mdadm.h
 	$(CC) $(CXFLAGS) $(LDFLAGS) -o test_stripe -DMAIN restripe.c
 
-mdassemble : $(ASSEMBLE_SRCS) mdadm.h
+mdassemble : $(ASSEMBLE_SRCS) $(INCL)
 	rm -f $(OBJS)
 	$(DIET_GCC) $(ASSEMBLE_FLAGS) -o mdassemble $(ASSEMBLE_SRCS)  $(STATICSRC)
 
-mdassemble.static : $(ASSEMBLE_SRCS) mdadm.h
+mdassemble.static : $(ASSEMBLE_SRCS) $(INCL)
 	rm -f $(OBJS)
 	$(CC) $(LDFLAGS) $(ASSEMBLE_FLAGS) -static -DHAVE_STDINT_H -o mdassemble.static $(ASSEMBLE_SRCS) $(STATICSRC)
 
-mdassemble.auto : $(ASSEMBLE_SRCS) mdadm.h $(ASSEMBLE_AUTO_SRCS)
+mdassemble.auto : $(ASSEMBLE_SRCS) $(INCL) $(ASSEMBLE_AUTO_SRCS)
 	rm -f mdassemble.static
 	$(MAKE) MDASSEMBLE_AUTO=1 mdassemble.static
 	mv mdassemble.static mdassemble.auto
 
-mdassemble.uclibc : $(ASSEMBLE_SRCS) mdadm.h
+mdassemble.uclibc : $(ASSEMBLE_SRCS) $(INCL)
 	rm -f $(OJS)
 	$(UCLIBC_GCC) $(ASSEMBLE_FLAGS) -DUCLIBC -DHAVE_STDINT_H -static -o mdassemble.uclibc $(ASSEMBLE_SRCS) $(STATICSRC)
 
 # This doesn't work
-mdassemble.klibc : $(ASSEMBLE_SRCS) mdadm.h
+mdassemble.klibc : $(ASSEMBLE_SRCS) $(INCL)
 	rm -f $(OBJS)
 	$(KLIBC_GCC) $(ASSEMBLE_FLAGS) -o mdassemble $(ASSEMBLE_SRCS)
 
@@ -213,8 +219,8 @@ mdadm.conf.man : mdadm.conf.5
 mdassemble.man : mdassemble.8
 	nroff -man mdassemble.8 > mdassemble.man
 
-$(OBJS) : mdadm.h mdmon.h bitmap.h
-$(MON_OBJS) : mdadm.h mdmon.h bitmap.h
+$(OBJS) : $(INCL) mdmon.h
+$(MON_OBJS) : $(INCL) mdmon.h
 
 sha1.o : sha1.c sha1.h md5.h
 	$(CC) $(CFLAGS) -DHAVE_STDINT_H -o sha1.o -c sha1.c
diff --git a/mdadm.h b/mdadm.h
index 1fe25745..f16cd7c0 100644
--- a/mdadm.h
+++ b/mdadm.h
@@ -671,9 +671,11 @@ extern struct superswitch {
 	int swapuuid; /* true if uuid is bigending rather than hostendian */
 	int external;
 	const char *name; /* canonical metadata name */
-} super0, super1, super_ddf, *superlist[];
+} *superlist[];
 
-extern struct superswitch super_imsm;
+extern struct superswitch super0, super1;
+extern struct superswitch super_imsm, super_ddf;
+extern struct superswitch mbr;
 
 struct metadata_update {
 	int	len;
diff --git a/part.h b/part.h
new file mode 100644
index 00000000..0afea33b
--- /dev/null
+++ b/part.h
@@ -0,0 +1,82 @@
+/*
+ * mdadm - manage Linux "md" devices aka RAID arrays.
+ *
+ * Copyright (C) 2010 Neil Brown <neilb@suse.de>
+ *
+ *
+ *    This program is free software; you can redistribute it and/or modify
+ *    it under the terms of the GNU General Public License as published by
+ *    the Free Software Foundation; either version 2 of the License, or
+ *    (at your option) any later version.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU General Public License for more details.
+ *
+ *    You should have received a copy of the GNU General Public License
+ *    along with this program; if not, write to the Free Software
+ *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ *    Author: Neil Brown
+ *    Email: <neil@brown.name>
+ *
+ */
+
+/* Structure definitions ext  for MBR and GPT partition tables
+ */
+
+
+#define	MBR_SIGNATURE_MAGIC	__cpu_to_le16(0xAA55)
+#define MBR_PARTITIONS               4
+
+struct MBR_part_record {
+  __u8 bootable;
+  __u8 first_head;
+  __u8 first_sector;
+  __u8 first_cyl;
+  __u8 part_type;
+  __u8 last_head;
+  __u8 last_sector;
+  __u8 last_cyl;
+  __u32 first_sect_lba;
+  __u32 blocks_num;
+};
+
+struct MBR {
+	__u8 pad[446];
+	struct MBR_part_record parts[MBR_PARTITIONS];
+	__u16 magic;
+} __attribute__((packed));
+
+
+
+#define	GPT_SIGNATURE_MAGIC	__cpu_to_le64(0x5452415020494645ULL)
+#define MBR_GPT_PARTITION_TYPE       0xEE
+
+struct GPT_part_entry {
+	unsigned char type_guid[16];
+	unsigned char partition_guid[16];
+	__u64 starting_lba;
+	__u64 ending_lba;
+	unsigned char attr_bits[8];
+	unsigned char name[72];
+} __attribute__((packed));
+
+struct GPT {
+	__u64 magic;
+	__u32 revision;
+	__u32 header_size;
+	__u32 crc;
+	__u32 pad1;
+	__u64 current_lba;
+	__u64 backup_lba;
+	__u64 first_lba;
+	__u64 last_lba;
+	__u8 guid[16];
+	__u64 part_start;
+	__u32 part_cnt;
+	__u32 part_size;
+	__u32 part_crc;
+	__u8 pad2[420];
+} __attribute__((packed));
diff --git a/super-mbr.c b/super-mbr.c
new file mode 100644
index 00000000..811ad1dc
--- /dev/null
+++ b/super-mbr.c
@@ -0,0 +1,213 @@
+/*
+ * mdadm - manage Linux "md" devices aka RAID arrays.
+ *
+ * Copyright (C) 2010 Neil Brown <neilb@suse.de>
+ *
+ *
+ *    This program is free software; you can redistribute it and/or modify
+ *    it under the terms of the GNU General Public License as published by
+ *    the Free Software Foundation; either version 2 of the License, or
+ *    (at your option) any later version.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU General Public License for more details.
+ *
+ *    You should have received a copy of the GNU General Public License
+ *    along with this program; if not, write to the Free Software
+ *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ *    Author: Neil Brown
+ *    Email: <neil@brown.name>
+ *
+ */
+
+/*
+ * 'mbr' is a pseudo metadata type for devices which have a
+ * partition table in the Master Boot Record (mbr) also known
+ * as a dos partition table.
+ *
+ * Obviously arrays cannot be created or assembled for this type.
+ * It is used to allow a new bare device to have an partition table
+ * added so the member partitions can then be included in other
+ * arrays as relevant.
+ *
+ * The meaning operations are:
+ * examine_super, but not brief_examine_super or export_examine
+ * load_super
+ * store_super
+ */
+
+#include "mdadm.h"
+#include "part.h"
+
+static void free_mbr(struct supertype *st)
+{
+	free(st->sb);
+	st->sb = NULL;
+}
+
+#ifndef MDASSEMBLE
+
+static void examine_mbr(struct supertype *st, char *homehost)
+{
+	struct MBR *sb = st->sb;
+	int i;
+
+	printf("   MBR Magic : %04x\n", sb->magic);
+	for (i = 0; i < MBR_PARTITIONS; i++)
+		if (sb->parts[i].blocks_num)
+			printf("Partition[%d] : %12lu sectors at %12lu (type %02x)\n",
+			       i,
+			       (unsigned long)__le32_to_cpu(sb->parts[i].blocks_num),
+			       (unsigned long)__le32_to_cpu(sb->parts[i].first_sect_lba),
+			       sb->parts[i].part_type);
+
+}
+
+#endif /*MDASSEMBLE */
+
+static int load_super_mbr(struct supertype *st, int fd, char *devname)
+{
+	/* try to read an mbr
+	 * Return
+	 *  0 on success
+	 *  1 cannot get record
+	 *  2 record is meaningless
+	 */
+	struct MBR *super;
+
+	free_mbr(st);
+
+	if (st->subarray[0])
+		return 1;
+
+	if (posix_memalign((void**)&super, 512, 512) != 0) {
+		fprintf(stderr, Name ": %s could not allocate superblock\n",
+			__func__);
+		return 1;
+	}
+
+	ioctl(fd, BLKFLSBUF, 0); /* make sure we read current data */
+
+	lseek(fd, 0, 0);
+	if (read(fd, super, sizeof(*super)) != sizeof(*super)) {
+		if (devname)
+			fprintf(stderr, Name ": Cannot read partition table on %s\n",
+				devname);
+		free(super);
+		return 1;
+	}
+ 
+	if (super->magic != MBR_SIGNATURE_MAGIC) {
+		if (devname)
+			fprintf(stderr, Name ": No partition table found on %s\n",
+				devname);
+		free(super);
+		return 1;
+	}
+
+	st->sb = super;
+
+	if (st->ss == NULL) {
+		st->ss = &mbr;
+		st->minor_version = 0;
+		st->max_devs = 1;
+		st->info = NULL;
+	}
+	return 0;
+}
+
+static int store_mbr(struct supertype *st, int fd)
+{
+	struct MBR *old, *super;
+
+	if (posix_memalign((void**)&old, 512, 512) != 0) {
+		fprintf(stderr, Name ": %s could not allocate superblock\n",
+			__func__);
+		return 1;
+	}
+
+	ioctl(fd, BLKFLSBUF, 0); /* make sure we read current data */
+
+	lseek(fd, 0, 0);
+	if (read(fd, old, sizeof(*old)) != sizeof(*old)) {
+		free(old);
+		return 1;
+	}
+
+	super = st->sb;
+	memcpy(super->pad, old->pad, sizeof(super->pad));
+	free(old);
+	lseek(fd, 0, 0);
+	if (write(fd, super, sizeof(*super)) != sizeof(*super))
+		return 4;
+	fsync(fd);
+	ioctl(fd, BLKRRPART, 0);
+	return 0;
+}
+
+static void getinfo_mbr(struct supertype *st, struct mdinfo *info)
+{
+	struct MBR *sb = st->sb;
+	int i;
+
+	memset(&info->array, 0, sizeof(info->array));
+	memset(&info->disk, 0, sizeof(info->disk));
+	strcpy(info->text_version, "mbr");
+	strcpy(info->name, "mbr");
+	info->component_size = 0;
+
+	for (i = 0; i < MBR_PARTITIONS ; i++)
+		if (sb->parts[i].blocks_num) {
+			unsigned long last = 
+				(unsigned long)__le32_to_cpu(sb->parts[i].blocks_num)
+				+ (unsigned long)__le32_to_cpu(sb->parts[i].first_sect_lba);
+			if (last > info->component_size)
+				info->component_size = last;
+		}
+
+}
+
+static struct supertype *match_metadata_desc(char *arg)
+{
+	struct supertype *st = malloc(sizeof(*st));
+
+	if (!st)
+		return st;
+	if (strcmp(arg, "mbr") != 0)
+		return NULL;
+
+	st->ss = &mbr;
+	st->info = NULL;
+	st->minor_version = 0;
+	st->max_devs = 1;
+	st->sb = NULL;
+	return st;
+}
+
+#ifndef MDASSEMBLE
+static int validate_geometry(struct supertype *st, int level,
+			     int layout, int raiddisks,
+			     int chunk, unsigned long long size,
+			     char *subdev, unsigned long long *freesize,
+			     int verbose)
+{
+	fprintf(stderr, Name ": mbr metadata cannot be used this way\n");
+	return 0;
+}
+#endif
+
+struct superswitch mbr = {
+#ifndef MDASSEMBLE
+	.examine_super = examine_mbr,
+#endif
+	.validate_geometry = validate_geometry,
+	.match_metadata_desc = match_metadata_desc,
+	.load_super = load_super_mbr,
+	.store_super = store_mbr,
+	.getinfo_super = getinfo_mbr,
+	.free_super = free_mbr,
+	.name = "mbr",
+};
diff --git a/util.c b/util.c
index c9bdd6eb..c93b0a7a 100644
--- a/util.c
+++ b/util.c
@@ -65,55 +65,7 @@ struct blkpg_partition {
 	char volname[BLKPG_VOLNAMELTH];	/* volume label */
 };
 
-/* partition table structures so we can check metadata position
- * against the end of the last partition.
- * Only handle MBR ant GPT partition tables.
- */
-struct MBR_part_record {
-  __u8 bootable;
-  __u8 first_head;
-  __u8 first_sector;
-  __u8 first_cyl;
-  __u8 part_type;
-  __u8 last_head;
-  __u8 last_sector;
-  __u8 last_cyl;
-  __u32 first_sect_lba;
-  __u32 blocks_num;
-};
-
-struct MBR {
-	__u8 pad[446];
-	struct MBR_part_record parts[4];
-	__u16 magic;
-} __attribute__((packed));
-
-struct GPT_part_entry {
-  unsigned char type_guid[16];
-  unsigned char partition_guid[16];
-  __u64 starting_lba;
-  __u64 ending_lba;
-  unsigned char attr_bits[8];
-  unsigned char name[72];
-} __attribute__((packed));
-
-struct GPT {
-	__u64 magic;
-	__u32 revision;
-	__u32 header_size;
-	__u32 crc;
-	__u32 pad1;
-	__u64 current_lba;
-	__u64 backup_lba;
-	__u64 first_lba;
-	__u64 last_lba;
-	__u8 guid[16];
-	__u64 part_start;
-	__u32 part_cnt;
-	__u32 part_size;
-	__u32 part_crc;
-	__u8 pad2[420];
-} __attribute__((packed));
+#include "part.h"
 
 /* Force a compilation error if condition is true */
 #define BUILD_BUG_ON(condition) ((void)BUILD_BUG_ON_ZERO(condition))
@@ -124,14 +76,6 @@ struct GPT {
    aren't permitted). */
 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
 
-
-/* MBR/GPT magic numbers */
-#define	MBR_SIGNATURE_MAGIC	__cpu_to_le16(0xAA55)
-#define	GPT_SIGNATURE_MAGIC	__cpu_to_le64(0x5452415020494645ULL)
-
-#define MBR_PARTITIONS               4
-#define MBR_GPT_PARTITION_TYPE       0xEE
-
 /*
  * Parse a 128 bit uuid in 4 integers
  * format is 32 hexx nibbles with options :.<space> separator
@@ -1049,7 +993,12 @@ void wait_for(char *dev, int fd)
 		dprintf("%s: timeout waiting for %s\n", __func__, dev);
 }
 
-struct superswitch *superlist[] = { &super0, &super1, &super_ddf, &super_imsm, NULL };
+struct superswitch *superlist[] =
+{
+	&super0, &super1,
+	&super_ddf, &super_imsm,
+	&mbr,
+	NULL };
 
 #if !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO)