Adding upstream version 2.39.3.upstream/2.39.3

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

8 files changed, 1173 insertions, 0 deletions

diff --git a/libblkid/src/topology/dm.c b/libblkid/src/topology/dm.c
new file mode 100644
index 0000000..612b5df
--- /dev/null
+++ b/libblkid/src/topology/dm.c
@@ -0,0 +1,134 @@
+/*
+ * device-mapper (dm) topology
+ * -- this is fallback for old systems where the topology information is not
+ *    exported by sysfs
+ *
+ * Copyright (C) 2009 Karel Zak <kzak@redhat.com>
+ *
+ * This file may be redistributed under the terms of the
+ * GNU Lesser General Public License.
+ *
+ */
+#include <errno.h>
+#include <fcntl.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "topology.h"
+
+static int is_dm_device(dev_t devno)
+{
+	return blkid_driver_has_major("device-mapper", major(devno));
+}
+
+static int probe_dm_tp(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
+{
+	const char * const paths[] = {
+		"/usr/local/sbin/dmsetup",
+		"/usr/sbin/dmsetup",
+		"/sbin/dmsetup"
+	};
+	int dmpipe[] = { -1, -1 }, stripes = 0, stripesize = 0;
+	const char *cmd = NULL;
+	FILE *stream = NULL;
+	long long  offset = 0, size = 0;
+	size_t i;
+	dev_t devno = blkid_probe_get_devno(pr);
+
+	if (!devno)
+		goto nothing;		/* probably not a block device */
+	if (!is_dm_device(devno))
+		goto nothing;
+
+	for (i = 0; i < ARRAY_SIZE(paths); i++) {
+		struct stat sb;
+		if (stat(paths[i], &sb) == 0) {
+			cmd = paths[i];
+			break;
+		}
+	}
+
+	if (!cmd)
+		goto nothing;
+	if (pipe(dmpipe) < 0) {
+		DBG(LOWPROBE, ul_debug("Failed to open pipe: errno=%d", errno));
+		goto nothing;
+	}
+
+	switch (fork()) {
+	case 0:
+	{
+		const char *dmargv[7];
+	        char maj[16], min[16];
+
+		/* Plumbing */
+		close(dmpipe[0]);
+
+		if (dmpipe[1] != STDOUT_FILENO)
+			dup2(dmpipe[1], STDOUT_FILENO);
+
+		if (drop_permissions() != 0)
+			 exit(1);
+
+		snprintf(maj, sizeof(maj), "%d", major(devno));
+		snprintf(min, sizeof(min), "%d", minor(devno));
+
+		dmargv[0] = cmd;
+		dmargv[1] = "table";
+		dmargv[2] = "-j";
+		dmargv[3] = maj;
+		dmargv[4] = "-m";
+		dmargv[5] = min;
+		dmargv[6] = NULL;
+
+		execv(dmargv[0], (char * const *) dmargv);
+
+		DBG(LOWPROBE, ul_debug("Failed to execute %s: errno=%d", cmd, errno));
+		exit(1);
+	}
+	case -1:
+		DBG(LOWPROBE, ul_debug("Failed to forking: errno=%d", errno));
+		goto nothing;
+	default:
+		break;
+	}
+
+	stream = fdopen(dmpipe[0], "r" UL_CLOEXECSTR);
+	if (!stream)
+		goto nothing;
+
+	if (dmpipe[1] != -1) {
+		close(dmpipe[1]);
+	}
+
+	if (fscanf(stream, "%lld %lld striped %d %d ",
+			&offset, &size, &stripes, &stripesize) != 0)
+		goto nothing;
+
+	blkid_topology_set_minimum_io_size(pr, stripesize << 9);
+	blkid_topology_set_optimal_io_size(pr, (stripes * stripesize) << 9);
+
+	fclose(stream);
+	return 0;
+
+nothing:
+	if (stream)
+		fclose(stream);
+	else if (dmpipe[0] != -1)
+		close(dmpipe[0]);
+	return 1;
+}
+
+const struct blkid_idinfo dm_tp_idinfo =
+{
+	.name		= "dm",
+	.probefunc	= probe_dm_tp,
+	.magics		= BLKID_NONE_MAGIC
+};
+
diff --git a/libblkid/src/topology/evms.c b/libblkid/src/topology/evms.c
new file mode 100644
index 0000000..1aa32f9
--- /dev/null
+++ b/libblkid/src/topology/evms.c
@@ -0,0 +1,77 @@
+/*
+ * Evms topology
+ * -- this is fallback for old systems where the topology information is not
+ *    exported by sysfs
+ *
+ * Copyright (C) 2009 Karel Zak <kzak@redhat.com>
+ *
+ * This file may be redistributed under the terms of the
+ * GNU Lesser General Public License.
+ *
+ */
+#include <errno.h>
+#include <fcntl.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "topology.h"
+
+#define EVMS_MAJOR		117
+
+#ifndef _IOT__IOTBASE_u_int32_t
+#define _IOT__IOTBASE_u_int32_t IOT_SIMPLE(uint32_t)
+#endif
+#define _IOT_evms_stripe_info _IOT (_IOTS(uint32_t), 2, 0, 0, 0, 0)
+#define EVMS_GET_STRIPE_INFO	_IOR(EVMS_MAJOR, 0xF0, struct evms_stripe_info)
+
+struct evms_stripe_info {
+	uint32_t	size;		/* stripe unit 512-byte blocks */
+	uint32_t	width;		/* the number of stripe members or RAID data disks */
+};
+
+static int is_evms_device(dev_t devno)
+{
+	if (major(devno) == EVMS_MAJOR)
+		return 1;
+	return blkid_driver_has_major("evms", major(devno));
+}
+
+static int probe_evms_tp(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
+{
+	struct evms_stripe_info evms;
+	dev_t devno = blkid_probe_get_devno(pr);
+
+	if (!devno)
+		goto nothing;		/* probably not a block device */
+
+	if (!is_evms_device(devno))
+		goto nothing;
+
+	memset(&evms, 0, sizeof(evms));
+
+	if (ioctl(pr->fd, EVMS_GET_STRIPE_INFO, &evms))
+		goto nothing;
+
+	blkid_topology_set_minimum_io_size(pr, evms.size << 9);
+	blkid_topology_set_optimal_io_size(pr, (evms.size * evms.width) << 9);
+
+	return 0;
+
+nothing:
+	return 1;
+}
+
+const struct blkid_idinfo evms_tp_idinfo =
+{
+	.name		= "evms",
+	.probefunc	= probe_evms_tp,
+	.magics		= BLKID_NONE_MAGIC
+};
+
diff --git a/libblkid/src/topology/ioctl.c b/libblkid/src/topology/ioctl.c
new file mode 100644
index 0000000..3560a2f
--- /dev/null
+++ b/libblkid/src/topology/ioctl.c
@@ -0,0 +1,83 @@
+/*
+ * ioctl based topology -- gathers topology information
+ *
+ * Copyright (C) 2009 Karel Zak <kzak@redhat.com>
+ *
+ * This file may be redistributed under the terms of the
+ * GNU Lesser General Public License.
+ *
+ */
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include "topology.h"
+
+/*
+ * ioctl topology values
+ */
+static const struct topology_val {
+
+	long  ioc;
+
+	/* functions to set probing result */
+	int (*set_ulong)(blkid_probe, unsigned long);
+	int (*set_int)(blkid_probe, int);
+	int (*set_u64)(blkid_probe, uint64_t);
+
+} topology_vals[] = {
+	{ BLKALIGNOFF, NULL, blkid_topology_set_alignment_offset },
+	{ BLKIOMIN, blkid_topology_set_minimum_io_size },
+	{ BLKIOOPT, blkid_topology_set_optimal_io_size },
+	{ BLKPBSZGET, blkid_topology_set_physical_sector_size },
+	{ BLKGETDISKSEQ, .set_u64 = blkid_topology_set_diskseq },
+	/* we read BLKSSZGET in topology.c */
+};
+
+static int probe_ioctl_tp(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
+{
+	size_t i;
+
+	for (i = 0; i < ARRAY_SIZE(topology_vals); i++) {
+		const struct topology_val *val = &topology_vals[i];
+		int rc = 1;
+		union {
+			unsigned long ul;
+			int i;
+			uint64_t u64;
+		} data;
+
+		if (ioctl(pr->fd, val->ioc, &data) == -1)
+			goto nothing;
+
+		if (val->set_int)
+			rc = val->set_int(pr, data.i);
+		else if (val->set_ulong)
+			rc = val->set_ulong(pr, data.ul);
+		else
+			rc = val->set_u64(pr, data.u64);
+
+		if (rc)
+			goto err;
+	}
+
+	return 0;
+nothing:
+	return 1;
+err:
+	return -1;
+}
+
+const struct blkid_idinfo ioctl_tp_idinfo =
+{
+	.name		= "ioctl",
+	.probefunc	= probe_ioctl_tp,
+	.magics		= BLKID_NONE_MAGIC
+};
+
diff --git a/libblkid/src/topology/lvm.c b/libblkid/src/topology/lvm.c
new file mode 100644
index 0000000..af1a612
--- /dev/null
+++ b/libblkid/src/topology/lvm.c
@@ -0,0 +1,144 @@
+/*
+ * lvm topology
+ * -- this is fallback for old systems where the topology information is not
+ *    exported by sysfs
+ *
+ * Copyright (C) 2009 Karel Zak <kzak@redhat.com>
+ *
+ * This file may be redistributed under the terms of the
+ * GNU Lesser General Public License.
+ *
+ */
+#include <errno.h>
+#include <fcntl.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "topology.h"
+
+#ifndef LVM_BLK_MAJOR
+# define LVM_BLK_MAJOR     58
+#endif
+
+static int is_lvm_device(dev_t devno)
+{
+	if (major(devno) == LVM_BLK_MAJOR)
+		return 1;
+	return blkid_driver_has_major("lvm", major(devno));
+}
+
+static int probe_lvm_tp(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
+{
+	const char * const paths[] = {
+		"/usr/local/sbin/lvdisplay",
+		"/usr/sbin/lvdisplay",
+		"/sbin/lvdisplay"
+	};
+	int lvpipe[] = { -1, -1 }, stripes = 0, stripesize = 0;
+	FILE *stream = NULL;
+	char *cmd = NULL, *devname = NULL, buf[1024];
+	size_t i;
+	dev_t devno = blkid_probe_get_devno(pr);
+
+	if (!devno)
+		goto nothing;		/* probably not a block device */
+	if (!is_lvm_device(devno))
+		goto nothing;
+
+	for (i = 0; i < ARRAY_SIZE(paths); i++) {
+		struct stat sb;
+		if (stat(paths[i], &sb) == 0) {
+			cmd = (char *) paths[i];
+			break;
+		}
+	}
+
+	if (!cmd)
+		goto nothing;
+
+	devname = blkid_devno_to_devname(devno);
+	if (!devname)
+		goto nothing;
+
+	if (pipe(lvpipe) < 0) {
+		DBG(LOWPROBE, ul_debug("Failed to open pipe: errno=%d", errno));
+		goto nothing;
+	}
+
+	switch (fork()) {
+	case 0:
+	{
+		char *lvargv[3];
+
+		/* Plumbing */
+		close(lvpipe[0]);
+
+		if (lvpipe[1] != STDOUT_FILENO)
+			dup2(lvpipe[1], STDOUT_FILENO);
+
+		if (drop_permissions() != 0)
+			 exit(1);
+
+		lvargv[0] = cmd;
+		lvargv[1] = devname;
+		lvargv[2] = NULL;
+
+		execv(lvargv[0], lvargv);
+
+		DBG(LOWPROBE, ul_debug("Failed to execute %s: errno=%d", cmd, errno));
+		exit(1);
+	}
+	case -1:
+		DBG(LOWPROBE, ul_debug("Failed to forking: errno=%d", errno));
+		goto nothing;
+	default:
+		break;
+	}
+
+	stream = fdopen(lvpipe[0], "r" UL_CLOEXECSTR);
+	if (!stream)
+		goto nothing;
+
+	while (fgets(buf, sizeof(buf), stream) != NULL) {
+		if (!strncmp(buf, "Stripes", 7))
+			ignore_result( sscanf(buf, "Stripes %d", &stripes) );
+
+		if (!strncmp(buf, "Stripe size", 11))
+			ignore_result( sscanf(buf, "Stripe size (KByte) %d", &stripesize) );
+	}
+
+	if (!stripes)
+		goto nothing;
+
+	blkid_topology_set_minimum_io_size(pr, stripesize << 10);
+	blkid_topology_set_optimal_io_size(pr, (stripes * stripesize) << 10);
+
+	free(devname);
+	fclose(stream);
+	close(lvpipe[1]);
+	return 0;
+
+nothing:
+	free(devname);
+	if (stream)
+		fclose(stream);
+	else if (lvpipe[0] != -1)
+		close(lvpipe[0]);
+	if (lvpipe[1] != -1)
+		close(lvpipe[1]);
+	return 1;
+}
+
+const struct blkid_idinfo lvm_tp_idinfo =
+{
+	.name		= "lvm",
+	.probefunc	= probe_lvm_tp,
+	.magics		= BLKID_NONE_MAGIC
+};
+
diff --git a/libblkid/src/topology/md.c b/libblkid/src/topology/md.c
new file mode 100644
index 0000000..02f27a8
--- /dev/null
+++ b/libblkid/src/topology/md.c
@@ -0,0 +1,154 @@
+/*
+ * Linux Software RAID (md) topology
+ * -- this is fallback for old systems where the topology information is not
+ *    exported by sysfs
+ *
+ * Copyright (C) 2009 Karel Zak <kzak@redhat.com>
+ *
+ * This file may be redistributed under the terms of the
+ * GNU Lesser General Public License.
+ *
+ */
+#include <errno.h>
+#include <fcntl.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "topology.h"
+
+#ifndef MD_MAJOR
+#define MD_MAJOR	9
+#endif
+
+#ifndef _IOT__IOTBASE_uint32_t
+#define _IOT__IOTBASE_uint32_t IOT_SIMPLE(uint32_t)
+#endif
+#define _IOT_md_array_info _IOT (_IOTS(uint32_t), 18, 0, 0, 0, 0)
+#define GET_ARRAY_INFO          _IOR (MD_MAJOR, 0x11, struct md_array_info)
+
+struct md_array_info {
+	/*
+	 * Generic constant information
+	 */
+	uint32_t major_version;
+	uint32_t minor_version;
+	uint32_t patch_version;
+	uint32_t ctime;
+	uint32_t level;
+	uint32_t size;
+	uint32_t nr_disks;
+	uint32_t raid_disks;
+	uint32_t md_minor;
+	uint32_t not_persistent;
+
+	/*
+	 * Generic state information
+	 */
+	uint32_t utime;	  /*  0 Superblock update time		  */
+	uint32_t state;	  /*  1 State bits (clean, ...)		  */
+	uint32_t active_disks;  /*  2 Number of currently active disks  */
+	uint32_t working_disks; /*  3 Number of working disks		  */
+	uint32_t failed_disks;  /*  4 Number of failed disks		  */
+	uint32_t spare_disks;	  /*  5 Number of spare disks		  */
+
+	/*
+	 * Personality information
+	 */
+	uint32_t layout;	  /*  0 the array's physical layout	  */
+	uint32_t chunk_size;	  /*  1 chunk size in bytes		  */
+
+};
+
+static int is_md_device(dev_t devno)
+{
+	if (major(devno) == MD_MAJOR)
+		return 1;
+	return blkid_driver_has_major("md", major(devno));
+}
+
+static int probe_md_tp(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
+{
+	int fd = -1;
+	dev_t disk = 0;
+	dev_t devno = blkid_probe_get_devno(pr);
+	struct md_array_info md;
+
+	if (!devno)
+		goto nothing;		/* probably not a block device */
+
+	if (!is_md_device(devno))
+		goto nothing;
+
+	if (blkid_devno_to_wholedisk(devno, NULL, 0, &disk))
+		goto nothing;
+
+	if (disk == devno)
+		fd = pr->fd;
+	else {
+		char *diskpath = blkid_devno_to_devname(disk);
+
+		if (!diskpath)
+			goto nothing;
+
+		fd = open(diskpath, O_RDONLY|O_CLOEXEC);
+		free(diskpath);
+
+                if (fd == -1)
+			goto nothing;
+	}
+
+	memset(&md, 0, sizeof(md));
+
+	if (ioctl(fd, GET_ARRAY_INFO, &md))
+		goto nothing;
+
+	if (fd >= 0 && fd != pr->fd) {
+		close(fd);
+		fd = -1;
+	}
+
+	/*
+	 * Ignore levels we don't want aligned (e.g. linear)
+	 * and deduct disk(s) from stripe width on RAID4/5/6
+	 */
+	switch (md.level) {
+	case 6:
+		md.raid_disks--;
+		/* fallthrough */
+	case 5:
+	case 4:
+		md.raid_disks--;
+		/* fallthrough */
+	case 1:
+	case 0:
+	case 10:
+		break;
+	default:
+		goto nothing;
+	}
+
+	blkid_topology_set_minimum_io_size(pr, md.chunk_size);
+	blkid_topology_set_optimal_io_size(pr, (unsigned long) md.chunk_size * md.raid_disks);
+
+	return 0;
+
+nothing:
+	if (fd >= 0 && fd != pr->fd)
+		close(fd);
+	return 1;
+}
+
+const struct blkid_idinfo md_tp_idinfo =
+{
+	.name		= "md",
+	.probefunc	= probe_md_tp,
+	.magics		= BLKID_NONE_MAGIC
+};
+
diff --git a/libblkid/src/topology/sysfs.c b/libblkid/src/topology/sysfs.c
new file mode 100644
index 0000000..25debd0
--- /dev/null
+++ b/libblkid/src/topology/sysfs.c
@@ -0,0 +1,132 @@
+/*
+ * sysfs based topology -- gathers topology information from Linux sysfs
+ *
+ * Copyright (C) 2009 Karel Zak <kzak@redhat.com>
+ *
+ * This file may be redistributed under the terms of the
+ * GNU Lesser General Public License.
+ *
+ * For more information see Linux kernel Documentation/ABI/testing/sysfs-block.
+ */
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <inttypes.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include "sysfs.h"
+#include "topology.h"
+
+/*
+ * Sysfs topology values (since 2.6.31, May 2009).
+ */
+static const struct topology_val {
+
+	/* /sys/dev/block/<maj>:<min>/<ATTR> */
+	const char *attr;
+
+	/* functions to set probing result */
+	int (*set_ulong)(blkid_probe, unsigned long);
+	int (*set_int)(blkid_probe, int);
+	int (*set_u64)(blkid_probe, uint64_t);
+
+} topology_vals[] = {
+	{ "alignment_offset", NULL, blkid_topology_set_alignment_offset },
+	{ "queue/minimum_io_size", blkid_topology_set_minimum_io_size },
+	{ "queue/optimal_io_size", blkid_topology_set_optimal_io_size },
+	{ "queue/physical_block_size", blkid_topology_set_physical_sector_size },
+	{ "queue/dax", blkid_topology_set_dax },
+	{ "diskseq", .set_u64 = blkid_topology_set_diskseq },
+};
+
+static int probe_sysfs_tp(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
+{
+	dev_t dev;
+	int rc, set_parent = 1;
+	struct path_cxt *pc;
+	size_t i, count = 0;
+
+	dev = blkid_probe_get_devno(pr);
+	if (!dev)
+		return 1;
+	pc = ul_new_sysfs_path(dev, NULL, NULL);
+	if (!pc)
+		return 1;
+
+	rc = 1;		/* nothing (default) */
+
+	for (i = 0; i < ARRAY_SIZE(topology_vals); i++) {
+		const struct topology_val *val = &topology_vals[i];
+		int ok = ul_path_access(pc, F_OK, val->attr) == 0;
+
+		rc = 1;	/* nothing */
+
+		if (!ok && set_parent) {
+			dev_t disk = blkid_probe_get_wholedisk_devno(pr);
+			set_parent = 0;
+
+			/*
+			 * Read attributes from "disk" if the current device is
+			 * a partition. Note that sysfs ul_path_* API is able
+			 * to redirect requests to attributes if parent is set.
+			 */
+			if (disk && disk != dev) {
+				struct path_cxt *parent = ul_new_sysfs_path(disk, NULL, NULL);
+				if (!parent)
+					goto done;
+
+				sysfs_blkdev_set_parent(pc, parent);
+				ul_unref_path(parent);
+
+				/* try it again */
+				ok = ul_path_access(pc, F_OK, val->attr) == 0;
+			}
+		}
+		if (!ok)
+			continue;	/* attribute does not exist */
+
+		if (val->set_ulong) {
+			uint64_t data;
+
+			if (ul_path_read_u64(pc, &data, val->attr) != 0)
+				continue;
+			rc = val->set_ulong(pr, (unsigned long) data);
+
+		} else if (val->set_int) {
+			int64_t data;
+
+			if (ul_path_read_s64(pc, &data, val->attr) != 0)
+				continue;
+			rc = val->set_int(pr, (int) data);
+		} else if (val->set_u64) {
+			uint64_t data;
+
+			if (ul_path_read_u64(pc, &data, val->attr) != 0)
+				continue;
+			rc = val->set_u64(pr, data);
+		}
+
+		if (rc < 0)
+			goto done;	/* error */
+		if (rc == 0)
+			count++;
+	}
+
+done:
+	ul_unref_path(pc);		/* unref pc and parent */
+	if (count)
+		return 0;		/* success */
+	return rc;			/* error or nothing */
+}
+
+const struct blkid_idinfo sysfs_tp_idinfo =
+{
+	.name		= "sysfs",
+	.probefunc	= probe_sysfs_tp,
+	.magics		= BLKID_NONE_MAGIC
+};
+
diff --git a/libblkid/src/topology/topology.c b/libblkid/src/topology/topology.c
new file mode 100644
index 0000000..67df3e3
--- /dev/null
+++ b/libblkid/src/topology/topology.c
@@ -0,0 +1,423 @@
+/*
+ * topology - gathers information about device topology
+ *
+ * Copyright 2009 Red Hat, Inc.  All rights reserved.
+ *
+ * This file may be redistributed under the terms of the
+ * GNU Lesser General Public License.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <inttypes.h>
+
+#include "topology.h"
+
+/**
+ * SECTION:topology
+ * @title: Topology information
+ * @short_description: block device topology information.
+ *
+ * The topology chain provides details about Linux block devices, for more
+ * information see:
+ *
+ *      Linux kernel Documentation/ABI/testing/sysfs-block
+ *
+ * NAME=value (tags) interface is enabled by blkid_probe_enable_topology(),
+ * and provides:
+ *
+ * @LOGICAL_SECTOR_SIZE: this is the smallest unit the storage device can
+ *                       address. It is typically 512 bytes.
+ *
+ * @PHYSICAL_SECTOR_SIZE: this is the smallest unit a physical storage device
+ *                        can write atomically. It is usually the same as the
+ *                        logical sector size but may be bigger.
+ *
+ * @MINIMUM_IO_SIZE: minimum size which is the device's preferred unit of I/O.
+ *                   For RAID arrays it is often the stripe chunk size.
+ *
+ * @OPTIMAL_IO_SIZE: usually the stripe width for RAID or zero. For RAID arrays
+ *                   it is usually the stripe width or the internal track size.
+ *
+ * @ALIGNMENT_OFFSET: indicates how many bytes the beginning of the device is
+ *                    offset from the disk's natural alignment.
+ *
+ * The NAME=value tags are not defined when the corresponding topology value
+ * is zero. The MINIMUM_IO_SIZE should be always defined if kernel provides
+ * topology information.
+ *
+ * Binary interface:
+ *
+ * blkid_probe_get_topology()
+ *
+ * blkid_topology_get_'VALUENAME'()
+ */
+static int topology_probe(blkid_probe pr, struct blkid_chain *chn);
+static void topology_free(blkid_probe pr, void *data);
+static int topology_is_complete(blkid_probe pr);
+static int topology_set_logical_sector_size(blkid_probe pr);
+
+/*
+ * Binary interface
+ */
+struct blkid_struct_topology {
+	unsigned long	alignment_offset;
+	unsigned long	minimum_io_size;
+	unsigned long	optimal_io_size;
+	unsigned long	logical_sector_size;
+	unsigned long	physical_sector_size;
+	unsigned long   dax;
+	uint64_t	diskseq;
+};
+
+/*
+ * Topology chain probing functions
+ */
+static const struct blkid_idinfo *idinfos[] =
+{
+#ifdef __linux__
+	&sysfs_tp_idinfo,
+	&ioctl_tp_idinfo,
+	&md_tp_idinfo,
+	&dm_tp_idinfo,
+	&lvm_tp_idinfo,
+	&evms_tp_idinfo
+#endif
+};
+
+
+/*
+ * Driver definition
+ */
+const struct blkid_chaindrv topology_drv = {
+	.id           = BLKID_CHAIN_TOPLGY,
+	.name         = "topology",
+	.dflt_enabled = FALSE,
+	.idinfos      = idinfos,
+	.nidinfos     = ARRAY_SIZE(idinfos),
+	.probe        = topology_probe,
+	.safeprobe    = topology_probe,
+	.free_data    = topology_free
+};
+
+/**
+ * blkid_probe_enable_topology:
+ * @pr: probe
+ * @enable: TRUE/FALSE
+ *
+ * Enables/disables the topology probing for non-binary interface.
+ *
+ * Returns: 0 on success, or -1 in case of error.
+ */
+int blkid_probe_enable_topology(blkid_probe pr, int enable)
+{
+	pr->chains[BLKID_CHAIN_TOPLGY].enabled = enable;
+	return 0;
+}
+
+/**
+ * blkid_probe_get_topology:
+ * @pr: probe
+ *
+ * This is a binary interface for topology values. See also blkid_topology_*
+ * functions.
+ *
+ * This function is independent on blkid_do_[safe,full]probe() and
+ * blkid_probe_enable_topology() calls.
+ *
+ * WARNING: the returned object will be overwritten by the next
+ *          blkid_probe_get_topology() call for the same @pr. If you want to
+ *          use more blkid_topology objects in the same time you have to create
+ *          more blkid_probe handlers (see blkid_new_probe()).
+ *
+ * Returns: blkid_topology, or NULL in case of error.
+ */
+blkid_topology blkid_probe_get_topology(blkid_probe pr)
+{
+	return (blkid_topology) blkid_probe_get_binary_data(pr,
+			&pr->chains[BLKID_CHAIN_TOPLGY]);
+}
+
+/*
+ * The blkid_do_probe() backend.
+ */
+static int topology_probe(blkid_probe pr, struct blkid_chain *chn)
+{
+	size_t i;
+
+	if (chn->idx < -1)
+		return -1;
+
+	if (!S_ISBLK(pr->mode))
+		return -EINVAL;	/* nothing, works with block devices only */
+
+	if (chn->binary) {
+		DBG(LOWPROBE, ul_debug("initialize topology binary data"));
+
+		if (chn->data)
+			/* reset binary data */
+			memset(chn->data, 0,
+					sizeof(struct blkid_struct_topology));
+		else {
+			chn->data = calloc(1,
+					sizeof(struct blkid_struct_topology));
+			if (!chn->data)
+				return -ENOMEM;
+		}
+	}
+
+	blkid_probe_chain_reset_values(pr, chn);
+
+	DBG(LOWPROBE, ul_debug("--> starting probing loop [TOPOLOGY idx=%d]",
+		chn->idx));
+
+	i = chn->idx < 0 ? 0 : chn->idx + 1U;
+
+	for ( ; i < ARRAY_SIZE(idinfos); i++) {
+		const struct blkid_idinfo *id = idinfos[i];
+
+		chn->idx = i;
+
+		if (id->probefunc) {
+			DBG(LOWPROBE, ul_debug("%s: call probefunc()", id->name));
+
+			errno = 0;
+			if (id->probefunc(pr, NULL) != 0)
+				continue;
+		}
+
+		if (!topology_is_complete(pr))
+			continue;
+
+		/* generic for all probing drivers */
+		topology_set_logical_sector_size(pr);
+
+		DBG(LOWPROBE, ul_debug("<-- leaving probing loop (type=%s) [TOPOLOGY idx=%d]",
+			id->name, chn->idx));
+		return BLKID_PROBE_OK;
+	}
+
+	DBG(LOWPROBE, ul_debug("<-- leaving probing loop (failed) [TOPOLOGY idx=%d]",
+		chn->idx));
+	return BLKID_PROBE_NONE;
+}
+
+static void topology_free(blkid_probe pr __attribute__((__unused__)),
+			  void *data)
+{
+	free(data);
+}
+
+static int topology_set_value(blkid_probe pr, const char *name,
+				size_t structoff, unsigned long data)
+{
+	struct blkid_chain *chn = blkid_probe_get_chain(pr);
+
+	if (!chn)
+		return -1;
+	if (!data)
+		return 0;	/* ignore zeros */
+
+	if (chn->binary) {
+		memcpy((char *) chn->data + structoff, &data, sizeof(data));
+		return 0;
+	}
+	return blkid_probe_sprintf_value(pr, name, "%lu", data);
+}
+
+static int topology_set_value64(blkid_probe pr, const char *name,
+				size_t structoff, uint64_t data)
+{
+	struct blkid_chain *chn = blkid_probe_get_chain(pr);
+
+	if (!chn)
+		return -1;
+	if (!data)
+		return 0;	/* ignore zeros */
+
+	if (chn->binary) {
+		memcpy((char *) chn->data + structoff, &data, sizeof(data));
+		return 0;
+	}
+	return blkid_probe_sprintf_value(pr, name, "%"PRIu64, data);
+}
+
+
+/* the topology info is complete when we have at least "minimum_io_size" which
+ * is provided by all blkid topology drivers */
+static int topology_is_complete(blkid_probe pr)
+{
+	struct blkid_chain *chn = blkid_probe_get_chain(pr);
+
+	if (!chn)
+		return FALSE;
+
+	if (chn->binary && chn->data) {
+		blkid_topology tp = (blkid_topology) chn->data;
+		if (tp->minimum_io_size)
+			return TRUE;
+	}
+
+	return __blkid_probe_lookup_value(pr, "MINIMUM_IO_SIZE") ? TRUE : FALSE;
+}
+
+int blkid_topology_set_alignment_offset(blkid_probe pr, int val)
+{
+	unsigned long xval;
+
+	/* Welcome to Hell. The kernel is able to return -1 as an
+	 * alignment_offset if no compatible sizes and alignments
+	 * exist for stacked devices.
+	 *
+	 * There is no way how libblkid caller can respond to the value -1, so
+	 * we will hide this corner case...
+	 *
+	 * (TODO: maybe we can export an extra boolean value 'misaligned' rather
+	 *  then complete hide this problem.)
+	 */
+	xval = val < 0 ? 0 : val;
+
+	return topology_set_value(pr,
+			"ALIGNMENT_OFFSET",
+			offsetof(struct blkid_struct_topology, alignment_offset),
+			xval);
+}
+
+int blkid_topology_set_minimum_io_size(blkid_probe pr, unsigned long val)
+{
+	return topology_set_value(pr,
+			"MINIMUM_IO_SIZE",
+			offsetof(struct blkid_struct_topology, minimum_io_size),
+			val);
+}
+
+int blkid_topology_set_optimal_io_size(blkid_probe pr, unsigned long val)
+{
+	return topology_set_value(pr,
+			"OPTIMAL_IO_SIZE",
+			offsetof(struct blkid_struct_topology, optimal_io_size),
+			val);
+}
+
+/* BLKSSZGET is provided on all systems since 2.3.3 -- so we don't have to
+ * waste time with sysfs.
+ */
+static int topology_set_logical_sector_size(blkid_probe pr)
+{
+	unsigned long val = blkid_probe_get_sectorsize(pr);
+
+	if (!val)
+		return -1;
+
+	return topology_set_value(pr,
+			"LOGICAL_SECTOR_SIZE",
+			offsetof(struct blkid_struct_topology, logical_sector_size),
+			val);
+}
+
+int blkid_topology_set_physical_sector_size(blkid_probe pr, unsigned long val)
+{
+	return topology_set_value(pr,
+			"PHYSICAL_SECTOR_SIZE",
+			offsetof(struct blkid_struct_topology, physical_sector_size),
+			val);
+}
+
+int blkid_topology_set_dax(blkid_probe pr, unsigned long val)
+{
+	return topology_set_value(pr,
+			"DAX",
+			offsetof(struct blkid_struct_topology, dax),
+			val);
+}
+
+int blkid_topology_set_diskseq(blkid_probe pr, uint64_t val)
+{
+	return topology_set_value64(pr,
+			"DISKSEQ",
+			offsetof(struct blkid_struct_topology, diskseq),
+			val);
+}
+
+/**
+ * blkid_topology_get_alignment_offset:
+ * @tp: topology
+ *
+ * Returns: alignment offset in bytes or 0.
+ */
+unsigned long blkid_topology_get_alignment_offset(blkid_topology tp)
+{
+	return tp->alignment_offset;
+}
+
+/**
+ * blkid_topology_get_minimum_io_size:
+ * @tp: topology
+ *
+ * Returns: minimum io size in bytes or 0.
+ */
+unsigned long blkid_topology_get_minimum_io_size(blkid_topology tp)
+{
+	return tp->minimum_io_size;
+}
+
+/**
+ * blkid_topology_get_optimal_io_size
+ * @tp: topology
+ *
+ * Returns: optimal io size in bytes or 0.
+ */
+unsigned long blkid_topology_get_optimal_io_size(blkid_topology tp)
+{
+	return tp->optimal_io_size;
+}
+
+/**
+ * blkid_topology_get_logical_sector_size
+ * @tp: topology
+ *
+ * Returns: logical sector size (BLKSSZGET ioctl) in bytes or 0.
+ */
+unsigned long blkid_topology_get_logical_sector_size(blkid_topology tp)
+{
+	return tp->logical_sector_size;
+}
+
+/**
+ * blkid_topology_get_physical_sector_size
+ * @tp: topology
+ *
+ * Returns: logical sector size (BLKSSZGET ioctl) in bytes or 0.
+ */
+unsigned long blkid_topology_get_physical_sector_size(blkid_topology tp)
+{
+	return tp->physical_sector_size;
+}
+
+/**
+ * blkid_topology_get_dax
+ * @tp: topology
+ *
+ * Returns: 1 if dax is supported, 0 otherwise.
+ *
+ * Since: 2.36
+ */
+unsigned long blkid_topology_get_dax(blkid_topology tp)
+{
+	return tp->dax;
+}
+
+/**
+ * blkid_topology_get_diskseq
+ * @tp: topology
+ *
+ * Returns: disk sequence number
+ *
+ * Since: 2.39
+ */
+uint64_t blkid_topology_get_diskseq(blkid_topology tp)
+{
+	return tp->diskseq;
+}
diff --git a/libblkid/src/topology/topology.h b/libblkid/src/topology/topology.h
new file mode 100644
index 0000000..9810fe4
--- /dev/null
+++ b/libblkid/src/topology/topology.h
@@ -0,0 +1,26 @@
+#ifndef BLKID_TOPOLOGY_H
+#define BLKID_TOPOLOGY_H
+
+#include "blkidP.h"
+
+extern int blkid_topology_set_alignment_offset(blkid_probe pr, int val);
+extern int blkid_topology_set_minimum_io_size(blkid_probe pr, unsigned long val);
+extern int blkid_topology_set_optimal_io_size(blkid_probe pr, unsigned long val);
+extern int blkid_topology_set_physical_sector_size(blkid_probe pr, unsigned long val);
+extern int blkid_topology_set_dax(blkid_probe pr, unsigned long val);
+extern int blkid_topology_set_diskseq(blkid_probe pr, uint64_t val);
+
+/*
+ * topology probers
+ */
+#ifdef __linux__
+extern const struct blkid_idinfo ioctl_tp_idinfo;
+extern const struct blkid_idinfo md_tp_idinfo;
+extern const struct blkid_idinfo evms_tp_idinfo;
+extern const struct blkid_idinfo sysfs_tp_idinfo;
+extern const struct blkid_idinfo dm_tp_idinfo;
+extern const struct blkid_idinfo lvm_tp_idinfo;
+#endif
+
+#endif /* BLKID_TOPOLOGY_H */
+