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path: root/cmd/zpool/os/linux/zpool_vdev_os.c
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/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or https://opensource.org/licenses/CDDL-1.0.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
 * Copyright (c) 2013, 2018 by Delphix. All rights reserved.
 * Copyright (c) 2016, 2017 Intel Corporation.
 * Copyright 2016 Igor Kozhukhov <ikozhukhov@gmail.com>.
 */

/*
 * Functions to convert between a list of vdevs and an nvlist representing the
 * configuration.  Each entry in the list can be one of:
 *
 * 	Device vdevs
 * 		disk=(path=..., devid=...)
 * 		file=(path=...)
 *
 * 	Group vdevs
 * 		raidz[1|2]=(...)
 * 		mirror=(...)
 *
 * 	Hot spares
 *
 * While the underlying implementation supports it, group vdevs cannot contain
 * other group vdevs.  All userland verification of devices is contained within
 * this file.  If successful, the nvlist returned can be passed directly to the
 * kernel; we've done as much verification as possible in userland.
 *
 * Hot spares are a special case, and passed down as an array of disk vdevs, at
 * the same level as the root of the vdev tree.
 *
 * The only function exported by this file is 'make_root_vdev'.  The
 * function performs several passes:
 *
 * 	1. Construct the vdev specification.  Performs syntax validation and
 *         makes sure each device is valid.
 * 	2. Check for devices in use.  Using libblkid to make sure that no
 *         devices are also in use.  Some can be overridden using the 'force'
 *         flag, others cannot.
 * 	3. Check for replication errors if the 'force' flag is not specified.
 *         validates that the replication level is consistent across the
 *         entire pool.
 * 	4. Call libzfs to label any whole disks with an EFI label.
 */

#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <libintl.h>
#include <libnvpair.h>
#include <libzutil.h>
#include <limits.h>
#include <sys/spa.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include "zpool_util.h"
#include <sys/zfs_context.h>

#include <scsi/scsi.h>
#include <scsi/sg.h>
#include <sys/efi_partition.h>
#include <sys/stat.h>
#include <sys/mntent.h>
#include <uuid/uuid.h>
#include <blkid/blkid.h>

typedef struct vdev_disk_db_entry
{
	char id[24];
	int sector_size;
} vdev_disk_db_entry_t;

/*
 * Database of block devices that lie about physical sector sizes.  The
 * identification string must be precisely 24 characters to avoid false
 * negatives
 */
static vdev_disk_db_entry_t vdev_disk_database[] = {
	{"ATA     ADATA SSD S396 3", 8192},
	{"ATA     APPLE SSD SM128E", 8192},
	{"ATA     APPLE SSD SM256E", 8192},
	{"ATA     APPLE SSD SM512E", 8192},
	{"ATA     APPLE SSD SM768E", 8192},
	{"ATA     C400-MTFDDAC064M", 8192},
	{"ATA     C400-MTFDDAC128M", 8192},
	{"ATA     C400-MTFDDAC256M", 8192},
	{"ATA     C400-MTFDDAC512M", 8192},
	{"ATA     Corsair Force 3 ", 8192},
	{"ATA     Corsair Force GS", 8192},
	{"ATA     INTEL SSDSA2CT04", 8192},
	{"ATA     INTEL SSDSA2BZ10", 8192},
	{"ATA     INTEL SSDSA2BZ20", 8192},
	{"ATA     INTEL SSDSA2BZ30", 8192},
	{"ATA     INTEL SSDSA2CW04", 8192},
	{"ATA     INTEL SSDSA2CW08", 8192},
	{"ATA     INTEL SSDSA2CW12", 8192},
	{"ATA     INTEL SSDSA2CW16", 8192},
	{"ATA     INTEL SSDSA2CW30", 8192},
	{"ATA     INTEL SSDSA2CW60", 8192},
	{"ATA     INTEL SSDSC2CT06", 8192},
	{"ATA     INTEL SSDSC2CT12", 8192},
	{"ATA     INTEL SSDSC2CT18", 8192},
	{"ATA     INTEL SSDSC2CT24", 8192},
	{"ATA     INTEL SSDSC2CW06", 8192},
	{"ATA     INTEL SSDSC2CW12", 8192},
	{"ATA     INTEL SSDSC2CW18", 8192},
	{"ATA     INTEL SSDSC2CW24", 8192},
	{"ATA     INTEL SSDSC2CW48", 8192},
	{"ATA     KINGSTON SH100S3", 8192},
	{"ATA     KINGSTON SH103S3", 8192},
	{"ATA     M4-CT064M4SSD2  ", 8192},
	{"ATA     M4-CT128M4SSD2  ", 8192},
	{"ATA     M4-CT256M4SSD2  ", 8192},
	{"ATA     M4-CT512M4SSD2  ", 8192},
	{"ATA     OCZ-AGILITY2    ", 8192},
	{"ATA     OCZ-AGILITY3    ", 8192},
	{"ATA     OCZ-VERTEX2 3.5 ", 8192},
	{"ATA     OCZ-VERTEX3     ", 8192},
	{"ATA     OCZ-VERTEX3 LT  ", 8192},
	{"ATA     OCZ-VERTEX3 MI  ", 8192},
	{"ATA     OCZ-VERTEX4     ", 8192},
	{"ATA     SAMSUNG MZ7WD120", 8192},
	{"ATA     SAMSUNG MZ7WD240", 8192},
	{"ATA     SAMSUNG MZ7WD480", 8192},
	{"ATA     SAMSUNG MZ7WD960", 8192},
	{"ATA     SAMSUNG SSD 830 ", 8192},
	{"ATA     Samsung SSD 840 ", 8192},
	{"ATA     SanDisk SSD U100", 8192},
	{"ATA     TOSHIBA THNSNH06", 8192},
	{"ATA     TOSHIBA THNSNH12", 8192},
	{"ATA     TOSHIBA THNSNH25", 8192},
	{"ATA     TOSHIBA THNSNH51", 8192},
	{"ATA     APPLE SSD TS064C", 4096},
	{"ATA     APPLE SSD TS128C", 4096},
	{"ATA     APPLE SSD TS256C", 4096},
	{"ATA     APPLE SSD TS512C", 4096},
	{"ATA     INTEL SSDSA2M040", 4096},
	{"ATA     INTEL SSDSA2M080", 4096},
	{"ATA     INTEL SSDSA2M160", 4096},
	{"ATA     INTEL SSDSC2MH12", 4096},
	{"ATA     INTEL SSDSC2MH25", 4096},
	{"ATA     OCZ CORE_SSD    ", 4096},
	{"ATA     OCZ-VERTEX      ", 4096},
	{"ATA     SAMSUNG MCCOE32G", 4096},
	{"ATA     SAMSUNG MCCOE64G", 4096},
	{"ATA     SAMSUNG SSD PM80", 4096},
	/* Flash drives optimized for 4KB IOs on larger pages */
	{"ATA     INTEL SSDSC2BA10", 4096},
	{"ATA     INTEL SSDSC2BA20", 4096},
	{"ATA     INTEL SSDSC2BA40", 4096},
	{"ATA     INTEL SSDSC2BA80", 4096},
	{"ATA     INTEL SSDSC2BB08", 4096},
	{"ATA     INTEL SSDSC2BB12", 4096},
	{"ATA     INTEL SSDSC2BB16", 4096},
	{"ATA     INTEL SSDSC2BB24", 4096},
	{"ATA     INTEL SSDSC2BB30", 4096},
	{"ATA     INTEL SSDSC2BB40", 4096},
	{"ATA     INTEL SSDSC2BB48", 4096},
	{"ATA     INTEL SSDSC2BB60", 4096},
	{"ATA     INTEL SSDSC2BB80", 4096},
	{"ATA     INTEL SSDSC2BW24", 4096},
	{"ATA     INTEL SSDSC2BW48", 4096},
	{"ATA     INTEL SSDSC2BP24", 4096},
	{"ATA     INTEL SSDSC2BP48", 4096},
	{"NA      SmrtStorSDLKAE9W", 4096},
	{"NVMe    Amazon EC2 NVMe ", 4096},
	/* Imported from Open Solaris */
	{"ATA     MARVELL SD88SA02", 4096},
	/* Advanced format Hard drives */
	{"ATA     Hitachi HDS5C303", 4096},
	{"ATA     SAMSUNG HD204UI ", 4096},
	{"ATA     ST2000DL004 HD20", 4096},
	{"ATA     WDC WD10EARS-00M", 4096},
	{"ATA     WDC WD10EARS-00S", 4096},
	{"ATA     WDC WD10EARS-00Z", 4096},
	{"ATA     WDC WD15EARS-00M", 4096},
	{"ATA     WDC WD15EARS-00S", 4096},
	{"ATA     WDC WD15EARS-00Z", 4096},
	{"ATA     WDC WD20EARS-00M", 4096},
	{"ATA     WDC WD20EARS-00S", 4096},
	{"ATA     WDC WD20EARS-00Z", 4096},
	{"ATA     WDC WD1600BEVT-0", 4096},
	{"ATA     WDC WD2500BEVT-0", 4096},
	{"ATA     WDC WD3200BEVT-0", 4096},
	{"ATA     WDC WD5000BEVT-0", 4096},
};


#define	INQ_REPLY_LEN	96
#define	INQ_CMD_LEN	6

static const int vdev_disk_database_size =
	sizeof (vdev_disk_database) / sizeof (vdev_disk_database[0]);

boolean_t
check_sector_size_database(char *path, int *sector_size)
{
	unsigned char inq_buff[INQ_REPLY_LEN];
	unsigned char sense_buffer[32];
	unsigned char inq_cmd_blk[INQ_CMD_LEN] =
	    {INQUIRY, 0, 0, 0, INQ_REPLY_LEN, 0};
	sg_io_hdr_t io_hdr;
	int error;
	int fd;
	int i;

	/* Prepare INQUIRY command */
	memset(&io_hdr, 0, sizeof (sg_io_hdr_t));
	io_hdr.interface_id = 'S';
	io_hdr.cmd_len = sizeof (inq_cmd_blk);
	io_hdr.mx_sb_len = sizeof (sense_buffer);
	io_hdr.dxfer_direction = SG_DXFER_FROM_DEV;
	io_hdr.dxfer_len = INQ_REPLY_LEN;
	io_hdr.dxferp = inq_buff;
	io_hdr.cmdp = inq_cmd_blk;
	io_hdr.sbp = sense_buffer;
	io_hdr.timeout = 10;		/* 10 milliseconds is ample time */

	if ((fd = open(path, O_RDONLY|O_DIRECT)) < 0)
		return (B_FALSE);

	error = ioctl(fd, SG_IO, (unsigned long) &io_hdr);

	(void) close(fd);

	if (error < 0)
		return (B_FALSE);

	if ((io_hdr.info & SG_INFO_OK_MASK) != SG_INFO_OK)
		return (B_FALSE);

	for (i = 0; i < vdev_disk_database_size; i++) {
		if (memcmp(inq_buff + 8, vdev_disk_database[i].id, 24))
			continue;

		*sector_size = vdev_disk_database[i].sector_size;
		return (B_TRUE);
	}

	return (B_FALSE);
}

static int
check_slice(const char *path, blkid_cache cache, int force, boolean_t isspare)
{
	int err;
	char *value;

	/* No valid type detected device is safe to use */
	value = blkid_get_tag_value(cache, "TYPE", path);
	if (value == NULL)
		return (0);

	/*
	 * If libblkid detects a ZFS device, we check the device
	 * using check_file() to see if it's safe.  The one safe
	 * case is a spare device shared between multiple pools.
	 */
	if (strcmp(value, "zfs_member") == 0) {
		err = check_file(path, force, isspare);
	} else {
		if (force) {
			err = 0;
		} else {
			err = -1;
			vdev_error(gettext("%s contains a filesystem of "
			    "type '%s'\n"), path, value);
		}
	}

	free(value);

	return (err);
}

/*
 * Validate that a disk including all partitions are safe to use.
 *
 * For EFI labeled disks this can done relatively easily with the libefi
 * library.  The partition numbers are extracted from the label and used
 * to generate the expected /dev/ paths.  Each partition can then be
 * checked for conflicts.
 *
 * For non-EFI labeled disks (MBR/EBR/etc) the same process is possible
 * but due to the lack of a readily available libraries this scanning is
 * not implemented.  Instead only the device path as given is checked.
 */
static int
check_disk(const char *path, blkid_cache cache, int force,
    boolean_t isspare, boolean_t iswholedisk)
{
	struct dk_gpt *vtoc;
	char slice_path[MAXPATHLEN];
	int err = 0;
	int fd, i;
	int flags = O_RDONLY|O_DIRECT;

	if (!iswholedisk)
		return (check_slice(path, cache, force, isspare));

	/* only spares can be shared, other devices require exclusive access */
	if (!isspare)
		flags |= O_EXCL;

	if ((fd = open(path, flags)) < 0) {
		char *value = blkid_get_tag_value(cache, "TYPE", path);
		(void) fprintf(stderr, gettext("%s is in use and contains "
		    "a %s filesystem.\n"), path, value ? value : "unknown");
		free(value);
		return (-1);
	}

	/*
	 * Expected to fail for non-EFI labeled disks.  Just check the device
	 * as given and do not attempt to detect and scan partitions.
	 */
	err = efi_alloc_and_read(fd, &vtoc);
	if (err) {
		(void) close(fd);
		return (check_slice(path, cache, force, isspare));
	}

	/*
	 * The primary efi partition label is damaged however the secondary
	 * label at the end of the device is intact.  Rather than use this
	 * label we should play it safe and treat this as a non efi device.
	 */
	if (vtoc->efi_flags & EFI_GPT_PRIMARY_CORRUPT) {
		efi_free(vtoc);
		(void) close(fd);

		if (force) {
			/* Partitions will now be created using the backup */
			return (0);
		} else {
			vdev_error(gettext("%s contains a corrupt primary "
			    "EFI label.\n"), path);
			return (-1);
		}
	}

	for (i = 0; i < vtoc->efi_nparts; i++) {

		if (vtoc->efi_parts[i].p_tag == V_UNASSIGNED ||
		    uuid_is_null((uchar_t *)&vtoc->efi_parts[i].p_guid))
			continue;

		if (strncmp(path, UDISK_ROOT, strlen(UDISK_ROOT)) == 0)
			(void) snprintf(slice_path, sizeof (slice_path),
			    "%s%s%d", path, "-part", i+1);
		else
			(void) snprintf(slice_path, sizeof (slice_path),
			    "%s%s%d", path, isdigit(path[strlen(path)-1]) ?
			    "p" : "", i+1);

		err = check_slice(slice_path, cache, force, isspare);
		if (err)
			break;
	}

	efi_free(vtoc);
	(void) close(fd);

	return (err);
}

int
check_device(const char *path, boolean_t force,
    boolean_t isspare, boolean_t iswholedisk)
{
	blkid_cache cache;
	int error;

	error = blkid_get_cache(&cache, NULL);
	if (error != 0) {
		(void) fprintf(stderr, gettext("unable to access the blkid "
		    "cache.\n"));
		return (-1);
	}

	error = check_disk(path, cache, force, isspare, iswholedisk);
	blkid_put_cache(cache);

	return (error);
}

void
after_zpool_upgrade(zpool_handle_t *zhp)
{
	(void) zhp;
}

int
check_file(const char *file, boolean_t force, boolean_t isspare)
{
	return (check_file_generic(file, force, isspare));
}

/*
 * Read from a sysfs file and return an allocated string.  Removes
 * the newline from the end of the string if there is one.
 *
 * Returns a string on success (which must be freed), or NULL on error.
 */
static char *zpool_sysfs_gets(char *path)
{
	int fd;
	struct stat statbuf;
	char *buf = NULL;
	ssize_t count = 0;
	fd = open(path, O_RDONLY);
	if (fd < 0)
		return (NULL);

	if (fstat(fd, &statbuf) != 0) {
		close(fd);
		return (NULL);
	}

	buf = calloc(sizeof (*buf), statbuf.st_size + 1);
	if (buf == NULL) {
		close(fd);
		return (NULL);
	}

	/*
	 * Note, we can read less bytes than st_size, and that's ok.  Sysfs
	 * files will report their size is 4k even if they only return a small
	 * string.
	 */
	count = read(fd, buf, statbuf.st_size);
	if (count < 0) {
		/* Error doing read() or we overran the buffer */
		close(fd);
		free(buf);
		return (NULL);
	}

	/* Remove trailing newline */
	if (buf[count - 1] == '\n')
		buf[count - 1] = 0;

	close(fd);

	return (buf);
}

/*
 * Write a string to a sysfs file.
 *
 * Returns 0 on success, non-zero otherwise.
 */
static int zpool_sysfs_puts(char *path, char *str)
{
	FILE *file;

	file = fopen(path, "w");
	if (!file) {
		return (-1);
	}

	if (fputs(str, file) < 0) {
		fclose(file);
		return (-2);
	}
	fclose(file);
	return (0);
}

/* Given a vdev nvlist_t, rescan its enclosure sysfs path */
static void
rescan_vdev_config_dev_sysfs_path(nvlist_t *vdev_nv)
{
	update_vdev_config_dev_sysfs_path(vdev_nv,
	    fnvlist_lookup_string(vdev_nv, ZPOOL_CONFIG_PATH),
	    ZPOOL_CONFIG_VDEV_ENC_SYSFS_PATH);
}

/*
 * Given a power string: "on", "off", "1", or "0", return 0 if it's an
 * off value, 1 if it's an on value, and -1 if the value is unrecognized.
 */
static int zpool_power_parse_value(char *str)
{
	if ((strcmp(str, "off") == 0) || (strcmp(str, "0") == 0))
		return (0);

	if ((strcmp(str, "on") == 0) || (strcmp(str, "1") == 0))
		return (1);

	return (-1);
}

/*
 * Given a vdev string return an allocated string containing the sysfs path to
 * its power control file.  Also do a check if the power control file really
 * exists and has correct permissions.
 *
 * Example returned strings:
 *
 * /sys/class/enclosure/0:0:122:0/10/power_status
 * /sys/bus/pci/slots/10/power
 *
 * Returns allocated string on success (which must be freed), NULL on failure.
 */
static char *
zpool_power_sysfs_path(zpool_handle_t *zhp, char *vdev)
{
	const char *enc_sysfs_dir = NULL;
	char *path = NULL;
	nvlist_t *vdev_nv = zpool_find_vdev(zhp, vdev, NULL, NULL, NULL);

	if (vdev_nv == NULL) {
		return (NULL);
	}

	/* Make sure we're getting the updated enclosure sysfs path */
	rescan_vdev_config_dev_sysfs_path(vdev_nv);

	if (nvlist_lookup_string(vdev_nv, ZPOOL_CONFIG_VDEV_ENC_SYSFS_PATH,
	    &enc_sysfs_dir) != 0) {
		return (NULL);
	}

	if (asprintf(&path, "%s/power_status", enc_sysfs_dir) == -1)
		return (NULL);

	if (access(path, W_OK) != 0) {
		free(path);
		path = NULL;
		/* No HDD 'power_control' file, maybe it's NVMe? */
		if (asprintf(&path, "%s/power", enc_sysfs_dir) == -1) {
			return (NULL);
		}

		if (access(path, R_OK | W_OK) != 0) {
			/* Not NVMe either */
			free(path);
			return (NULL);
		}
	}

	return (path);
}

/*
 * Given a path to a sysfs power control file, return B_TRUE if you should use
 * "on/off" words to control it, or B_FALSE otherwise ("0/1" to control).
 */
static boolean_t
zpool_power_use_word(char *sysfs_path)
{
	if (strcmp(&sysfs_path[strlen(sysfs_path) - strlen("power_status")],
	    "power_status") == 0) {
		return (B_TRUE);
	}
	return (B_FALSE);
}

/*
 * Check the sysfs power control value for a vdev.
 *
 * Returns:
 *  0 - Power is off
 *  1 - Power is on
 * -1 - Error or unsupported
 */
int
zpool_power_current_state(zpool_handle_t *zhp, char *vdev)
{
	char *val;
	int rc;

	char *path = zpool_power_sysfs_path(zhp, vdev);
	if (path == NULL)
		return (-1);

	val = zpool_sysfs_gets(path);
	if (val == NULL) {
		free(path);
		return (-1);
	}

	rc = zpool_power_parse_value(val);
	free(val);
	free(path);
	return (rc);
}

/*
 * Turn on or off the slot to a device
 *
 * Device path is the full path to the device (like /dev/sda or /dev/sda1).
 *
 * Return code:
 * 0:		Success
 * ENOTSUP:	Power control not supported for OS
 * EBADSLT:	Couldn't read current power state
 * ENOENT:	No sysfs path to power control
 * EIO:	Couldn't write sysfs power value
 * EBADE:	Sysfs power value didn't change
 */
int
zpool_power(zpool_handle_t *zhp, char *vdev, boolean_t turn_on)
{
	char *sysfs_path;
	const char *val;
	int rc;
	int timeout_ms;

	rc = zpool_power_current_state(zhp, vdev);
	if (rc == -1) {
		return (EBADSLT);
	}

	/* Already correct value? */
	if (rc == (int)turn_on)
		return (0);

	sysfs_path = zpool_power_sysfs_path(zhp, vdev);
	if (sysfs_path == NULL)
		return (ENOENT);

	if (zpool_power_use_word(sysfs_path)) {
		val = turn_on ? "on" : "off";
	} else {
		val = turn_on ? "1" : "0";
	}

	rc = zpool_sysfs_puts(sysfs_path, (char *)val);

	free(sysfs_path);
	if (rc != 0) {
		return (EIO);
	}

	/*
	 * Wait up to 30 seconds for sysfs power value to change after
	 * writing it.
	 */
	timeout_ms = zpool_getenv_int("ZPOOL_POWER_ON_SLOT_TIMEOUT_MS", 30000);
	for (int i = 0; i < MAX(1, timeout_ms / 200); i++) {
		rc = zpool_power_current_state(zhp, vdev);
		if (rc == (int)turn_on)
			return (0);	/* success */

		fsleep(0.200);	/* 200ms */
	}

	/* sysfs value never changed */
	return (EBADE);
}