lsblk: add new utility

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Karel Zak <kzak@redhat.com>

1 files changed, 1062 insertions, 0 deletions

diff --git a/misc-utils/lsblk.c b/misc-utils/lsblk.c
new file mode 100644
index 000000000..f863e1c6c
--- /dev/null
+++ b/misc-utils/lsblk.c
@@ -0,0 +1,1062 @@
+/*
+ * lsblk(1) - list block devices
+ *
+ * Copyright (C) 2010 Red Hat, Inc. All rights reserved.
+ * Written by Milan Broz <mbroz@redhat.com>
+ *            Karel Zak <kzak@redhat.com>
+ *
+ * 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 would 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
+ */
+
+#include <stdio.h>
+#include <errno.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <string.h>
+#include <err.h>
+#include <sys/ioctl.h>
+#include <inttypes.h>
+#include <stdarg.h>
+#include <locale.h>
+#include <pwd.h>
+#include <grp.h>
+
+#include <blkid.h>
+
+#include <assert.h>
+
+#include "pathnames.h"
+#include "blkdev.h"
+#include "canonicalize.h"
+#include "ismounted.h"
+#include "nls.h"
+#include "tt.h"
+#include "xalloc.h"
+#include "strutils.h"
+
+/* column IDs */
+enum {
+	COL_NAME = 0,
+	COL_KNAME,
+	COL_MAJMIN,
+	COL_FSTYPE,
+	COL_TARGET,
+	COL_LABEL,
+	COL_UUID,
+	COL_RO,
+	COL_RA,
+	COL_MODEL,
+	COL_SIZE,
+	COL_OWNER,
+	COL_GROUP,
+	COL_MODE,
+	COL_ALIOFF,
+	COL_MINIO,
+	COL_OPTIO,
+	COL_PHYSEC,
+	COL_LOGSEC,
+	COL_ROTA,
+	COL_SCHED,
+
+	__NCOLUMNS
+};
+
+/* column names */
+struct colinfo {
+	const char	*name;		/* header */
+	double		whint;		/* width hint (N < 1 is in percent of termwidth) */
+	int		flags;		/* TT_FL_* */
+	const char      *help;
+};
+
+/* columns descriptions */
+static struct colinfo infos[__NCOLUMNS] = {
+	[COL_NAME]   = { "NAME",    0.25, TT_FL_TREE, N_("device name") },
+	[COL_KNAME]  = { "KNAME",   0.3, 0, N_("internel kernel device name") },
+	[COL_MAJMIN] = { "MAJ:MIN", 6, 0, N_("major:minor device number") },
+	[COL_FSTYPE] = { "FSTYPE",  0.1, TT_FL_TRUNC, N_("filesystem type") },
+	[COL_TARGET] = { "MOUNTPOINT", 0.10, TT_FL_TRUNC, N_("where the device is mounted") },
+	[COL_LABEL]  = { "LABEL",   0.1, 0, N_("filesystem LABEL") },
+	[COL_UUID]   = { "UUID",    36,  0, N_("filesystem UUID") },
+	[COL_RO]     = { "RO",      1, TT_FL_RIGHT, N_("read-only device") },
+	[COL_RA]     = { "RA",      1, TT_FL_RIGHT, N_("removable device") },
+	[COL_ROTA]   = { "ROTA",    1, TT_FL_RIGHT, N_("rotational device") },
+	[COL_MODEL]  = { "MODEL",   0.1, TT_FL_TRUNC, N_("device identifier") },
+	[COL_SIZE]   = { "SIZE",    6, TT_FL_RIGHT, N_("size of the device") },
+	[COL_OWNER]  = { "OWNER",   0.1, TT_FL_TRUNC, N_("user name"), },
+	[COL_GROUP]  = { "GROUP",   0.1, TT_FL_TRUNC, N_("group name") },
+	[COL_MODE]   = { "MODE",    10,   0, N_("device node permissions") },
+	[COL_ALIOFF] = { "ALIGNMENT", 6, TT_FL_RIGHT, N_("alignment offset") },
+	[COL_MINIO]  = { "MIN-IO",  6, TT_FL_RIGHT, N_("minimum I/O size") },
+	[COL_OPTIO]  = { "OPT-IO",  6, TT_FL_RIGHT, N_("optimal I/O size") },
+	[COL_PHYSEC] = { "PHY-SEC", 7, TT_FL_RIGHT, N_("physical sector size") },
+	[COL_LOGSEC] = { "LOG-SEC", 7, TT_FL_RIGHT, N_("logical sector size") },
+	[COL_SCHED]  = { "SCHED",   0.1, 0, N_("I/O scheduler name") }
+
+};
+
+struct lsblk {
+	struct tt *tt;		/* output table */
+	int all_devices:1;	/* print all devices */
+	int bytes:1;		/* print SIZE in bytes */
+};
+
+struct lsblk *lsblk;	/* global handler */
+int columns[__NCOLUMNS];/* enabled columns */
+int ncolumns;		/* number of enabled columns */
+
+unsigned int excludes[256];
+int nexcludes;
+
+struct blkdev_cxt {
+	struct blkdev_cxt *parent;
+
+	struct tt_line *tt_line;
+	struct stat	st;
+
+	char *name;		/* kernel name in /sys/block */
+	char *dm_name;		/* DM name (dm/block) */
+
+	char *filename;		/* path to device node */
+	int sysfs_fd;		/* O_RDONLY file desciptor to /sys/block/<dev> */
+
+	int partition;		/* is partition? TRUE/FALSE */
+
+	int probed;		/* already probed */
+	char *fstype;		/* detected fs, NULL or "?" if cannot detect */
+	char *uuid;		/* UUID of device / filesystem */
+	char *label;		/* FS label */
+
+	int nholders;		/* # of devices mapped directly to this device
+				 * /sys/block/.../holders + number of partition */
+	int nslaves;		/* # of devices this device maps to */
+	int maj, min;		/* devno */
+
+	uint64_t size;		/* device size */
+};
+
+static int is_maj_excluded(int maj)
+{
+	int i;
+
+	assert(ARRAY_SIZE(excludes) > nexcludes);
+
+	for (i = 0; i < nexcludes; i++)
+		if (excludes[i] == maj)
+			return 1;
+	return 0;
+}
+
+
+/* array with IDs of enabled columns */
+static int get_column_id(int num)
+{
+	assert(ARRAY_SIZE(columns) == __NCOLUMNS);
+	assert(num < ncolumns);
+	assert(columns[num] < __NCOLUMNS);
+	return columns[num];
+}
+
+static struct colinfo *get_column_info(int num)
+{
+	return &infos[ get_column_id(num) ];
+}
+
+
+static int column_name_to_id(const char *name, size_t namesz)
+{
+	int i;
+
+	for (i = 0; i < __NCOLUMNS; i++) {
+		const char *cn = infos[i].name;
+
+		if (!strncasecmp(name, cn, namesz) && !*(cn + namesz))
+			return i;
+	}
+	warnx(_("unknown column: %s"), name);
+	return -1;
+}
+
+static void reset_blkdev_cxt(struct blkdev_cxt *cxt)
+{
+	if (!cxt)
+		return;
+	free(cxt->name);
+	free(cxt->dm_name);
+	free(cxt->filename);
+	free(cxt->fstype);
+	free(cxt->uuid);
+	free(cxt->label);
+
+	if (cxt->sysfs_fd >= 0)
+		close(cxt->sysfs_fd);
+
+	memset(cxt, 0, sizeof(*cxt));
+}
+
+static int is_dm(const char *name)
+{
+	return strncmp(name, "dm-", 3) ? 0 : 1;
+}
+
+static struct dirent *xreaddir(DIR *dp)
+{
+	struct dirent *d;
+
+	assert(dp);
+
+	while ((d = readdir(dp))) {
+		if (!strcmp(d->d_name, ".") ||
+		    !strcmp(d->d_name, ".."))
+			continue;
+
+		/* blacklist here? */
+		break;
+	}
+	return d;
+}
+
+/*
+ * returns exponent (2^x=n) in range KiB..PiB
+ */
+static int get_exp(uint64_t n)
+{
+	int shft;
+
+	for (shft = 10; shft <= 60; shft += 10) {
+		if (n < (1ULL << shft))
+			break;
+	}
+	return shft - 10;
+}
+
+static char *size_to_human_string(uint64_t bytes)
+{
+	char buf[32];
+	int dec, frac, exp;
+	const char *letters = "BKMGTP";
+	char c;
+
+	exp  = get_exp(bytes);
+	c    = *(letters + (exp ? exp / 10 : 0));
+	dec  = exp ? bytes / (1ULL << exp) : bytes;
+	frac = exp ? bytes % (1ULL << exp) : 0;
+
+	if (frac) {
+		/* round */
+		frac = (frac / (1ULL << (exp - 10)) + 50) / 100;
+		if (frac == 10)
+			dec++, frac = 0;
+	}
+
+	if (frac) {
+		struct lconv const *l = localeconv();
+		char *dp = l ? l->decimal_point : NULL;
+
+		if (!dp || !*dp)
+			dp = ".";
+		snprintf(buf, sizeof(buf), "%d%s%d%c", dec, dp, frac, c);
+	} else
+		snprintf(buf, sizeof(buf), "%d%c", dec, c);
+
+	return xstrdup(buf);
+}
+
+
+static int is_partition_dirent(DIR *dir, struct dirent *d, const char *parent_name)
+{
+	char path[256];
+
+	assert(dir);
+	assert(d);
+
+#ifdef _DIRENT_HAVE_D_TYPE
+	if (d->d_type != DT_DIR)
+		return 0;
+#endif
+	if (strncmp(parent_name, d->d_name, strlen(parent_name)))
+		return 0;
+
+	/* Cannot use /partition file, not supported on old sysfs */
+	snprintf(path, sizeof(path), "%s/start", d->d_name);
+
+	return faccessat(dirfd(dir), path, R_OK, 0) == 0;
+}
+
+static char *get_device_path(struct blkdev_cxt *cxt)
+{
+	char path[PATH_MAX];
+
+	assert(cxt);
+	assert(cxt->name);
+
+	if (is_dm(cxt->name))
+		return canonicalize_dm_name(cxt->name);
+
+	snprintf(path, sizeof(path), "/dev/%s", cxt->name);
+	return xstrdup(path);
+}
+
+static char *get_sysfs_path(struct blkdev_cxt *cxt)
+{
+	char path[PATH_MAX];
+
+	assert(cxt);
+	assert(cxt->name);
+
+	if (cxt->partition && cxt->parent)
+		snprintf(path, sizeof(path), _PATH_SYS_BLOCK "/%s/%s",
+			 cxt->parent->name, cxt->name);
+	else
+		snprintf(path, sizeof(path), _PATH_SYS_BLOCK "/%s", cxt->name);
+
+	return xstrdup(path);
+}
+
+static int sysfs_open(struct blkdev_cxt *cxt, const char *attr)
+{
+	int fd;
+
+	assert(cxt);
+	assert(cxt->sysfs_fd >= 0);
+
+	fd = openat(cxt->sysfs_fd, attr, O_RDONLY);
+	if (fd == -1 && errno == ENOENT && !strncmp(attr, "queue/", 6) && cxt->parent) {
+		fd = openat(cxt->parent->sysfs_fd, attr, O_RDONLY);
+	}
+	return fd;
+}
+
+static FILE *sysfs_fopen(struct blkdev_cxt *cxt, const char *attr)
+{
+	int fd = sysfs_open(cxt, attr);
+
+	return fd < 0 ? NULL : fdopen(fd, "r");
+}
+
+static DIR *sysfs_opendir(struct blkdev_cxt *cxt, const char *attr)
+{
+	DIR *dir;
+	int fd;
+
+	if (attr)
+		fd = sysfs_open(cxt, attr);
+	else {
+		/* request to open root of device in sysfs (/sys/block/<dev>)
+		 * -- we cannot use cxt->sysfs_fd directly, because closedir()
+		 * will close this our persistent file descriptor.
+		 */
+		assert(cxt);
+		assert(cxt->sysfs_fd >= 0);
+
+		fd = dup(cxt->sysfs_fd);
+	}
+
+	if (fd < 0)
+		return NULL;
+	dir = fdopendir(fd);
+	if (!dir) {
+		close(fd);
+		return NULL;
+	}
+	if (!attr)
+		 rewinddir(dir);
+	return dir;
+}
+
+static __attribute__ ((format (scanf, 3, 4)))
+int sysfs_scanf(struct blkdev_cxt *cxt,  const char *attr, const char *fmt, ...)
+{
+	FILE *f = sysfs_fopen(cxt, attr);
+	va_list ap;
+	int rc;
+
+	if (!f)
+		return -EINVAL;
+	va_start(ap, fmt);
+	rc = vfscanf(f, fmt, ap);
+	va_end(ap);
+
+	fclose(f);
+	return rc;
+}
+
+static uint64_t sysfs_read_u64(struct blkdev_cxt *cxt, const char *attr)
+{
+	uint64_t x;
+	return sysfs_scanf(cxt, attr, "%"SCNu64, &x) == 1 ? x : 0;
+}
+
+static char *sysfs_strdup(struct blkdev_cxt *cxt, const char *attr)
+{
+	char buf[1024];
+	return sysfs_scanf(cxt, attr, "%1024[^\n]", buf) == 1 ?
+						xstrdup(buf) : NULL;
+}
+
+static int sysfs_count_dirents(struct blkdev_cxt *cxt, const char *attr)
+{
+	DIR *dir;
+	int r = 0;
+
+	if (!(dir = sysfs_opendir(cxt, attr)))
+		return 0;
+
+	while (xreaddir(dir)) r++;
+
+	closedir(dir);
+	return r;
+}
+
+static int sysfs_count_partitions(struct blkdev_cxt *cxt)
+{
+	DIR *dir;
+	struct dirent *d;
+	int r = 0;
+
+	if (!(dir = sysfs_opendir(cxt, NULL)))
+		return 0;
+
+	while ((d = xreaddir(dir))) {
+		if (is_partition_dirent(dir, d, cxt->name))
+			r++;
+	}
+
+	closedir(dir);
+	return r;
+}
+
+static char *get_device_mountpoint(struct blkdev_cxt *cxt)
+{
+	int fl = 0;
+	char mnt[PATH_MAX];
+
+	*mnt = '\0';
+
+	/*
+	 * TODO: use libmount and parse /proc/mountinfo only once
+	 */
+	if (check_mount_point(cxt->filename, &fl, mnt, sizeof(mnt)) == 0 &&
+	    (fl & MF_MOUNTED)) {
+		if (fl & MF_SWAP)
+			strcpy(mnt, "[SWAP]");
+	}
+	return strlen(mnt) ? xstrdup(mnt) : NULL;
+}
+
+/* TODO: read info from udev db (if possible) for non-root users
+ */
+static void probe_device(struct blkdev_cxt *cxt)
+{
+	char *path = NULL;
+	blkid_probe pr = NULL;
+
+	if (cxt->probed)
+		return;
+	cxt->probed = 1;
+
+	if (!cxt->size)
+		return;
+
+	pr = blkid_new_probe_from_filename(cxt->filename);
+	if (!pr)
+		return;
+
+	/* TODO: we have to enable partitions probing to avoid conflicts
+	 *       between raids and PT -- see blkid(8) code for more details
+	 */
+	blkid_probe_enable_superblocks(pr, 1);
+	blkid_probe_set_superblocks_flags(pr, BLKID_SUBLKS_LABEL |
+					      BLKID_SUBLKS_UUID |
+					      BLKID_SUBLKS_TYPE);
+	if (!blkid_do_safeprobe(pr)) {
+		const char *data = NULL;
+
+		if (!blkid_probe_lookup_value(pr, "TYPE", &data, NULL))
+			cxt->fstype = xstrdup(data);
+		if (!blkid_probe_lookup_value(pr, "UUID", &data, NULL))
+			cxt->uuid = xstrdup(data);
+		if (!blkid_probe_lookup_value(pr, "LABEL", &data, NULL))
+			cxt->label = xstrdup(data);
+	}
+
+	free(path);
+	blkid_free_probe(pr);
+	return;
+}
+
+static int is_readonly_device(struct blkdev_cxt *cxt)
+{
+	int fd, ro = 0;
+
+	if (sysfs_scanf(cxt, "ro", "%d", &ro) == 0)
+		return ro;
+
+	/* fallback if "ro" attribute does not exist */
+	fd = open(cxt->filename, O_RDONLY);
+	if (fd != -1) {
+		ioctl(fd, BLKROGET, &ro);
+		close(fd);
+	}
+	return ro;
+}
+
+static char *get_scheduler(struct blkdev_cxt *cxt)
+{
+	char *str = sysfs_strdup(cxt, "queue/scheduler");
+	char *p, *res = NULL;
+
+	if (!str)
+		return NULL;
+	p = strchr(str, '[');
+	if (p) {
+		res = p + 1;
+		p = strchr(res, ']');
+		if (p) {
+			*p = '\0';
+			res = xstrdup(res);
+		} else
+			res = NULL;
+	}
+	free(str);
+	return res;
+}
+
+static void set_tt_data(struct blkdev_cxt *cxt, int col, int id, struct tt_line *ln)
+{
+	char buf[1024];
+	char *p;
+
+	if (!cxt->st.st_rdev && (id == COL_OWNER || id == COL_GROUP ||
+				 id == COL_MODE))
+		stat(cxt->filename, &cxt->st);
+
+	switch(id) {
+	case COL_NAME:
+		if (cxt->dm_name) {
+			snprintf(buf, sizeof(buf), "%s (%s)",
+					cxt->dm_name, cxt->name);
+			tt_line_set_data(ln, col, xstrdup(buf));
+			break;
+		}
+	case COL_KNAME:
+		tt_line_set_data(ln, col, xstrdup(cxt->name));
+		break;
+	case COL_OWNER:
+	{
+		struct passwd *pw = getpwuid(cxt->st.st_uid);
+		if (pw)
+			tt_line_set_data(ln, col, xstrdup(pw->pw_name));
+		break;
+	}
+	case COL_GROUP:
+	{
+		struct group *gr = getgrgid(cxt->st.st_gid);
+		if (gr)
+			tt_line_set_data(ln, col, xstrdup(gr->gr_name));
+		break;
+	}
+	case COL_MODE:
+	{
+		char md[11];
+		strmode(cxt->st.st_mode, md);
+		tt_line_set_data(ln, col, xstrdup(md));
+		break;
+	}
+	case COL_MAJMIN:
+		if (lsblk->tt->flags & TT_FL_RAW)
+			snprintf(buf, sizeof(buf), "%u:%u", cxt->maj, cxt->min);
+		else
+			snprintf(buf, sizeof(buf), "%3u:%-3u", cxt->maj, cxt->min);
+		tt_line_set_data(ln, col, xstrdup(buf));
+		break;
+	case COL_FSTYPE:
+		probe_device(cxt);
+		if (cxt->fstype)
+			tt_line_set_data(ln, col, xstrdup(cxt->fstype));
+		break;
+	case COL_TARGET:
+		if (!cxt->nholders) {
+			p = get_device_mountpoint(cxt);
+			if (p)
+				tt_line_set_data(ln, col, p);
+		}
+		break;
+	case COL_LABEL:
+		probe_device(cxt);
+		if (cxt->label)
+			tt_line_set_data(ln, col, xstrdup(cxt->label));
+		break;
+	case COL_UUID:
+		probe_device(cxt);
+		if (cxt->uuid)
+			tt_line_set_data(ln, col, xstrdup(cxt->uuid));
+		break;
+	case COL_RO:
+		tt_line_set_data(ln, col, is_readonly_device(cxt) ?
+					xstrdup("1") : xstrdup("0"));
+		break;
+	case COL_RA:
+		p = sysfs_strdup(cxt, "removable");
+		if (!p && cxt->parent)
+			p = sysfs_strdup(cxt->parent, "removable");
+		if (p)
+			tt_line_set_data(ln, col, p);
+		break;
+	case COL_ROTA:
+		p = sysfs_strdup(cxt, "queue/rotational");
+		if (p)
+			tt_line_set_data(ln, col, p);
+		break;
+	case COL_MODEL:
+		if (!cxt->partition && cxt->nslaves == 0) {
+			p = sysfs_strdup(cxt, "device/model");
+			if (p)
+				tt_line_set_data(ln, col, p);
+		}
+		break;
+	case COL_SIZE:
+		if (cxt->size) {
+			if (lsblk->bytes) {
+				if (asprintf(&p, "%jd", cxt->size) < 0)
+					p = NULL;
+			} else
+				p = size_to_human_string(cxt->size);
+			if (p)
+				tt_line_set_data(ln, col, p);
+		}
+		break;
+	case COL_ALIOFF:
+		p = sysfs_strdup(cxt, "alignment_offset");
+		if (p)
+			tt_line_set_data(ln, col, p);
+		break;
+	case COL_MINIO:
+		p = sysfs_strdup(cxt, "queue/minimum_io_size");
+		if (p)
+			tt_line_set_data(ln, col, p);
+		break;
+	case COL_OPTIO:
+		p = sysfs_strdup(cxt, "queue/optimal_io_size");
+		if (p)
+			tt_line_set_data(ln, col, p);
+		break;
+	case COL_PHYSEC:
+		p = sysfs_strdup(cxt, "queue/physical_block_size");
+		if (p)
+			tt_line_set_data(ln, col, p);
+		break;
+	case COL_LOGSEC:
+		p = sysfs_strdup(cxt, "queue/logical_block_size");
+		if (p)
+			tt_line_set_data(ln, col, p);
+		break;
+	case COL_SCHED:
+		p = get_scheduler(cxt);
+		if (p)
+			tt_line_set_data(ln, col, p);
+		break;
+	};
+}
+
+static void print_device(struct blkdev_cxt *cxt, struct tt_line *tt_parent)
+{
+	int i;
+
+	cxt->tt_line = tt_add_line(lsblk->tt, tt_parent);
+
+	for (i = 0; i < ncolumns; i++)
+		set_tt_data(cxt, i, get_column_id(i), cxt->tt_line);
+}
+
+static int set_cxt(struct blkdev_cxt *cxt,
+		    struct blkdev_cxt *parent,
+		    const char *name,
+		    int partition)
+{
+	char *p;
+
+	cxt->parent = parent;
+	cxt->name = xstrdup(name);
+	cxt->partition = partition;
+
+	cxt->filename = get_device_path(cxt);
+
+	/* open /sys/block/<name> */
+	p = get_sysfs_path(cxt);
+	cxt->sysfs_fd = open(p, O_RDONLY);
+	if (cxt->sysfs_fd < 0)
+		err(EXIT_FAILURE, _("%s: open failed"), p);
+	free(p);
+
+	if (sysfs_scanf(cxt, "dev", "%u:%u", &cxt->maj, &cxt->min) != 2)
+		return -1;
+
+	cxt->size = sysfs_read_u64(cxt, "size") << 9;
+
+	/* Ignore devices of zero size */
+	if (!lsblk->all_devices && cxt->size == 0)
+		return -1;
+
+	if (is_dm(name))
+		cxt->dm_name = sysfs_strdup(cxt, "dm/name");
+
+	cxt->nholders = sysfs_count_dirents(cxt, "holders") +
+			sysfs_count_partitions(cxt);
+	cxt->nslaves = sysfs_count_dirents(cxt, "slaves");
+
+	return 0;
+}
+
+/*
+ * List devices (holders) mapped to device
+ */
+static int list_holders(struct blkdev_cxt *cxt)
+{
+	DIR *dir;
+	struct dirent *d;
+	struct blkdev_cxt holder = {};
+
+	assert(cxt);
+	assert(cxt->sysfs_fd >= 0);
+
+	if (!cxt->nholders)
+		return 0;
+
+	/* Partitions */
+	dir = sysfs_opendir(cxt, NULL);
+	if (!dir)
+		err(EXIT_FAILURE, _("failed to open device directory in sysfs"));
+
+	while ((d = xreaddir(dir))) {
+		if (!is_partition_dirent(dir, d, cxt->name))
+			continue;
+
+		set_cxt(&holder, cxt, d->d_name, 1);
+		print_device(&holder, cxt->tt_line);
+		list_holders(&holder);
+		reset_blkdev_cxt(&holder);
+	}
+	closedir(dir);
+
+	/* Holders */
+	dir = sysfs_opendir(cxt, "holders");
+	if (!dir)
+		return 0;
+
+	while ((d = xreaddir(dir))) {
+		set_cxt(&holder, cxt, d->d_name, 0);
+		print_device(&holder, cxt->tt_line);
+		list_holders(&holder);
+		reset_blkdev_cxt(&holder);
+	}
+	closedir(dir);
+
+	return 0;
+}
+
+/* Iterate top-level devices in sysfs */
+static int iterate_block_devices(void)
+{
+	DIR *dir;
+	struct dirent *d;
+	struct blkdev_cxt cxt = {};
+
+	if (!(dir = opendir(_PATH_SYS_BLOCK)))
+		return EXIT_FAILURE;
+
+	while ((d = xreaddir(dir))) {
+
+		if (set_cxt(&cxt, NULL, d->d_name, 0))
+			goto next;
+
+		/* Skip devices in the middle of dependence tree */
+		if (cxt.nslaves > 0)
+			goto next;
+
+		if (!lsblk->all_devices && is_maj_excluded(cxt.maj))
+			goto next;
+
+		print_device(&cxt, NULL);
+		list_holders(&cxt);
+	next:
+		reset_blkdev_cxt(&cxt);
+	}
+
+	closedir(dir);
+
+	return EXIT_SUCCESS;
+}
+
+static int process_one_device(char *devname)
+{
+	struct blkdev_cxt parent = {}, cxt = {};
+	struct stat st;
+	char buf[PATH_MAX];
+	dev_t disk = 0;
+
+	if (stat(devname, &st) || !S_ISBLK(st.st_mode)) {
+		warnx(_("%s: not a block device"), devname);
+		return EXIT_FAILURE;
+	}
+	if (blkid_devno_to_wholedisk(st.st_rdev, buf, sizeof(buf), &disk)) {
+		warn(_("%s: failed to get whole-list devno"), devname);
+		return EXIT_FAILURE;
+	}
+	if (st.st_rdev == disk)
+		/*
+		 * unpartitioned device
+		 */
+		set_cxt(&cxt, NULL, buf, 0);
+	else {
+		/*
+		 * Parititioned, read sysfs name of the device
+		 */
+		size_t len;
+		char path[PATH_MAX], *diskname, *name;
+
+		snprintf(path, sizeof(path), "/sys/dev/block/%d:%d",
+				    major(st.st_rdev), minor(st.st_rdev));
+		diskname = xstrdup(buf);
+
+		len = readlink(path, buf, sizeof(buf));
+		if (len < 0) {
+			warn(_("%s: failed to read link"), path);
+			return EXIT_FAILURE;
+		}
+		buf[len] = '\0';
+
+		/* sysfs device name */
+		name = strrchr(buf, '/') + 1;
+
+		set_cxt(&parent, NULL, diskname, 0);
+		set_cxt(&cxt, &parent, name, 1);
+
+		free(diskname);
+	}
+
+	print_device(&cxt, NULL);
+	list_holders(&cxt);
+	reset_blkdev_cxt(&cxt);
+
+	if (st.st_rdev != disk)
+		reset_blkdev_cxt(&parent);
+
+	return EXIT_SUCCESS;
+}
+
+static void parse_excludes(const char *str)
+{
+	nexcludes = 0;
+
+	while (str && *str) {
+		char *end = NULL;
+		unsigned int n;
+
+		errno = 0;
+		n = strtoul(str, &end, 10);
+
+		if (end == str || (errno != 0 && (n == ULONG_MAX || n == 0)))
+			err(EXIT_FAILURE, _("failed to parse list '%s'"), str);
+		excludes[nexcludes++] = n;
+
+		if (nexcludes == ARRAY_SIZE(excludes))
+			errx(EXIT_FAILURE, _("the list of excluded devices is "
+					"too large (limit is %d devices)"),
+					(int)ARRAY_SIZE(excludes));
+		str = end && *end ? end + 1 : NULL;
+	}
+}
+
+static int __attribute__((__noreturn__)) help(FILE *out)
+{
+	int i;
+
+	fprintf(out, _(
+		"\nUsage:\n"
+		" %s [options] [<device> ...]\n"), program_invocation_short_name);
+
+	fprintf(out, _(
+		"\nOptions:\n"
+		" -a, --all            print all devices\n"
+		" -b, --bytes          print SIZE in bytes rather than in human readable format\n"
+		" -e, --exclude <list> exclude devices by major number (default: RAM disks)\n"
+		" -f, --fs             output info about filesystems\n"
+		" -h, --help           usage information (this)\n"
+		" -i, --ascii          use ascii characters only\n"
+		" -m, --perms          output info about permissions\n"
+		" -l, --list           use list format ouput\n"
+		" -n, --noheadings     don't print headings\n"
+		" -o, --output <list>  output columns\n"
+		" -r, --raw            use raw format output\n"
+		" -t, --topology       output info about topology\n"));
+
+	fprintf(out, _("\nAvailable columns:\n"));
+
+	for (i = 0; i < __NCOLUMNS; i++)
+		fprintf(out, " %10s  %s\n", infos[i].name, gettext(infos[i].help));
+
+	fprintf(out, _("\nFor more information see lsblk(1).\n"));
+
+	exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
+}
+
+static int __attribute__((__noreturn__))
+errx_mutually_exclusive(const char *opts)
+{
+	errx(EXIT_FAILURE, "%s %s", opts, _("options are mutually exclusive"));
+}
+
+int main(int argc, char *argv[])
+{
+	struct lsblk _ls;
+	int tt_flags = TT_FL_TREE;
+	int i, c, status = EXIT_FAILURE;
+
+	struct option longopts[] = {
+		{ "all",	0, 0, 'a' },
+		{ "help",	0, 0, 'h' },
+		{ "output",     1, 0, 'o' },
+		{ "perms",      0, 0, 'm' },
+		{ "noheadings",	0, 0, 'n' },
+		{ "list",       0, 0, 'l' },
+		{ "ascii",	0, 0, 'i' },
+		{ "raw",        0, 0, 'r' },
+		{ "fs",         0, 0, 'f' },
+		{ "exclude",    1, 0, 'e' },
+		{ "topology",   0, 0, 't' },
+		{ NULL, 0, 0, 0 },
+	};
+
+	setlocale(LC_ALL, "");
+	bindtextdomain(PACKAGE, LOCALEDIR);
+	textdomain(PACKAGE);
+
+	lsblk = &_ls;
+	memset(lsblk, 0, sizeof(*lsblk));
+
+	while((c = getopt_long(argc, argv, "abe:fhlnmo:irt", longopts, NULL)) != -1) {
+		switch(c) {
+		case 'a':
+			lsblk->all_devices = 1;
+			break;
+		case 'b':
+			lsblk->bytes = 1;
+			break;
+		case 'e':
+			parse_excludes(optarg);
+			break;
+		case 'h':
+			help(stdout);
+			break;
+		case 'l':
+			if (tt_flags & TT_FL_RAW)
+				errx_mutually_exclusive("--{raw,list}");
+
+			tt_flags &= ~TT_FL_TREE; /* disable the default */
+			break;
+		case 'n':
+			tt_flags |= TT_FL_NOHEADINGS;
+			break;
+		case 'o':
+			if (tt_parse_columns_list(optarg, columns, &ncolumns,
+						column_name_to_id))
+				return EXIT_FAILURE;
+			break;
+		case 'i':
+			tt_flags = TT_FL_ASCII;
+			break;
+		case 'r':
+			tt_flags &= ~TT_FL_TREE;	/* disable the default */
+			tt_flags |= TT_FL_RAW;		/* enable raw */
+			break;
+		case 'f':
+			columns[ncolumns++] = COL_NAME;
+			columns[ncolumns++] = COL_FSTYPE;
+			columns[ncolumns++] = COL_LABEL;
+			columns[ncolumns++] = COL_TARGET;
+			break;
+		case 'm':
+			columns[ncolumns++] = COL_NAME;
+			columns[ncolumns++] = COL_SIZE;
+			columns[ncolumns++] = COL_OWNER;
+			columns[ncolumns++] = COL_GROUP;
+			columns[ncolumns++] = COL_MODE;
+			break;
+		case 't':
+			columns[ncolumns++] = COL_NAME;
+			columns[ncolumns++] = COL_ALIOFF;
+			columns[ncolumns++] = COL_MINIO;
+			columns[ncolumns++] = COL_OPTIO;
+			columns[ncolumns++] = COL_PHYSEC;
+			columns[ncolumns++] = COL_LOGSEC;
+			columns[ncolumns++] = COL_ROTA;
+			columns[ncolumns++] = COL_SCHED;
+			break;
+		default:
+			help(stderr);
+		}
+	}
+
+	if (!ncolumns) {
+		columns[ncolumns++] = COL_NAME;
+		columns[ncolumns++] = COL_MAJMIN;
+		columns[ncolumns++] = COL_RA;
+		columns[ncolumns++] = COL_SIZE;
+		columns[ncolumns++] = COL_RO;
+		columns[ncolumns++] = COL_TARGET;
+	}
+
+	if (nexcludes && lsblk->all_devices)
+		errx_mutually_exclusive("--{all,exclude}");
+	else if (!nexcludes)
+		excludes[nexcludes++] = 1;	/* default: ignore RAM disks */
+	/*
+	 * initialize output columns
+	 */
+	if (!(lsblk->tt = tt_new_table(tt_flags)))
+		errx(EXIT_FAILURE, _("failed to initialize output table"));
+
+	for (i = 0; i < ncolumns; i++) {
+		struct colinfo *ci = get_column_info(i);
+		int fl = ci->flags;
+
+		if (!(tt_flags & TT_FL_TREE) && get_column_id(i) == COL_NAME)
+			fl &= ~TT_FL_TREE;
+
+		if (!tt_define_column(lsblk->tt, ci->name, ci->whint, fl)) {
+			warn(_("failed to initialize output column"));
+			goto leave;
+		}
+	}
+
+	if (optind == argc)
+		status = iterate_block_devices();
+	else while (optind < argc)
+		status = process_one_device(argv[optind++]);
+
+	tt_print_table(lsblk->tt);
+
+leave:
+	tt_free_table(lsblk->tt);
+	return status;
+}