mirror_zfs/cmd/zinject/translate.c
Paul Dagnelie 108a454a46
Add support for boot environment data to be stored in the label
Modern bootloaders leverage data stored in the root filesystem to 
enable some of their powerful features. GRUB specifically has a grubenv 
file which can store large amounts of configuration data that can be 
read and written at boot time and during normal operation. This allows 
sysadmins to configure useful features like automated failover after 
failed boot attempts. Unfortunately, due to the Copy-on-Write nature 
of ZFS, the standard behavior of these tools cannot handle writing to
ZFS files safely at boot time. We need an alternative way to store 
data that allows the bootloader to make changes to the data.

This work is very similar to work that was done on Illumos to enable 
similar functionality in the FreeBSD bootloader. This patch is different 
in that the data being stored is a raw grubenv file; this file can store 
arbitrary variables and values, and the scripting provided by grub is 
powerful enough that special structures are not required to implement 
advanced behavior.

We repurpose the second padding area in each label to store the grubenv 
file, protected by an embedded checksum. We add two ioctls to get and 
set this data, and libzfs_core and libzfs functions to access them more 
easily. There are no direct command line interfaces to these functions; 
these will be added directly to the bootloader utilities.

Reviewed-by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes #10009
2020-05-07 09:36:33 -07:00

398 lines
9.2 KiB
C

/*
* 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 http://www.opensolaris.org/os/licensing.
* 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) 2006, 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2012, 2020 by Delphix. All rights reserved.
*/
#include <libzfs.h>
#include <errno.h>
#include <fcntl.h>
#include <stdarg.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <strings.h>
#include <sys/file.h>
#include <sys/mntent.h>
#include <sys/mnttab.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/dmu.h>
#include <sys/dmu_objset.h>
#include <sys/dnode.h>
#include <sys/vdev_impl.h>
#include <sys/mkdev.h>
#include "zinject.h"
static int debug;
static void
ziprintf(const char *fmt, ...)
{
va_list ap;
if (!debug)
return;
va_start(ap, fmt);
(void) vprintf(fmt, ap);
va_end(ap);
}
static void
compress_slashes(const char *src, char *dest)
{
while (*src != '\0') {
*dest = *src++;
while (*dest == '/' && *src == '/')
++src;
++dest;
}
*dest = '\0';
}
/*
* Given a full path to a file, translate into a dataset name and a relative
* path within the dataset. 'dataset' must be at least MAXNAMELEN characters,
* and 'relpath' must be at least MAXPATHLEN characters. We also pass a stat64
* buffer, which we need later to get the object ID.
*/
static int
parse_pathname(const char *inpath, char *dataset, char *relpath,
struct stat64 *statbuf)
{
struct extmnttab mp;
const char *rel;
char fullpath[MAXPATHLEN];
compress_slashes(inpath, fullpath);
if (fullpath[0] != '/') {
(void) fprintf(stderr, "invalid object '%s': must be full "
"path\n", fullpath);
usage();
return (-1);
}
if (getextmntent(fullpath, &mp, statbuf) != 0) {
(void) fprintf(stderr, "cannot find mountpoint for '%s'\n",
fullpath);
return (-1);
}
if (strcmp(mp.mnt_fstype, MNTTYPE_ZFS) != 0) {
(void) fprintf(stderr, "invalid path '%s': not a ZFS "
"filesystem\n", fullpath);
return (-1);
}
if (strncmp(fullpath, mp.mnt_mountp, strlen(mp.mnt_mountp)) != 0) {
(void) fprintf(stderr, "invalid path '%s': mountpoint "
"doesn't match path\n", fullpath);
return (-1);
}
(void) strcpy(dataset, mp.mnt_special);
rel = fullpath + strlen(mp.mnt_mountp);
if (rel[0] == '/')
rel++;
(void) strcpy(relpath, rel);
return (0);
}
/*
* Convert from a dataset to a objset id. Note that
* we grab the object number from the inode number.
*/
static int
object_from_path(const char *dataset, uint64_t object, zinject_record_t *record)
{
zfs_handle_t *zhp;
if ((zhp = zfs_open(g_zfs, dataset, ZFS_TYPE_DATASET)) == NULL)
return (-1);
record->zi_objset = zfs_prop_get_int(zhp, ZFS_PROP_OBJSETID);
record->zi_object = object;
zfs_close(zhp);
return (0);
}
/*
* Initialize the range based on the type, level, and range given.
*/
static int
initialize_range(err_type_t type, int level, char *range,
zinject_record_t *record)
{
/*
* Determine the numeric range from the string.
*/
if (range == NULL) {
/*
* If range is unspecified, set the range to [0,-1], which
* indicates that the whole object should be treated as an
* error.
*/
record->zi_start = 0;
record->zi_end = -1ULL;
} else {
char *end;
/* XXX add support for suffixes */
record->zi_start = strtoull(range, &end, 10);
if (*end == '\0')
record->zi_end = record->zi_start + 1;
else if (*end == ',')
record->zi_end = strtoull(end + 1, &end, 10);
if (*end != '\0') {
(void) fprintf(stderr, "invalid range '%s': must be "
"a numeric range of the form 'start[,end]'\n",
range);
return (-1);
}
}
switch (type) {
default:
break;
case TYPE_DATA:
break;
case TYPE_DNODE:
/*
* If this is a request to inject faults into the dnode, then we
* must translate the current (objset,object) pair into an
* offset within the metadnode for the objset. Specifying any
* kind of range with type 'dnode' is illegal.
*/
if (range != NULL) {
(void) fprintf(stderr, "range cannot be specified when "
"type is 'dnode'\n");
return (-1);
}
record->zi_start = record->zi_object * sizeof (dnode_phys_t);
record->zi_end = record->zi_start + sizeof (dnode_phys_t);
record->zi_object = 0;
break;
}
record->zi_level = level;
return (0);
}
int
translate_record(err_type_t type, const char *object, const char *range,
int level, zinject_record_t *record, char *poolname, char *dataset)
{
char path[MAXPATHLEN];
char *slash;
struct stat64 statbuf;
int ret = -1;
debug = (getenv("ZINJECT_DEBUG") != NULL);
ziprintf("translating: %s\n", object);
if (MOS_TYPE(type)) {
/*
* MOS objects are treated specially.
*/
switch (type) {
default:
break;
case TYPE_MOS:
record->zi_type = 0;
break;
case TYPE_MOSDIR:
record->zi_type = DMU_OT_OBJECT_DIRECTORY;
break;
case TYPE_METASLAB:
record->zi_type = DMU_OT_OBJECT_ARRAY;
break;
case TYPE_CONFIG:
record->zi_type = DMU_OT_PACKED_NVLIST;
break;
case TYPE_BPOBJ:
record->zi_type = DMU_OT_BPOBJ;
break;
case TYPE_SPACEMAP:
record->zi_type = DMU_OT_SPACE_MAP;
break;
case TYPE_ERRLOG:
record->zi_type = DMU_OT_ERROR_LOG;
break;
}
dataset[0] = '\0';
(void) strcpy(poolname, object);
return (0);
}
/*
* Convert a full path into a (dataset, file) pair.
*/
if (parse_pathname(object, dataset, path, &statbuf) != 0)
goto err;
ziprintf(" dataset: %s\n", dataset);
ziprintf(" path: %s\n", path);
/*
* Convert (dataset, file) into (objset, object)
*/
if (object_from_path(dataset, statbuf.st_ino, record) != 0)
goto err;
ziprintf("raw objset: %llu\n", record->zi_objset);
ziprintf("raw object: %llu\n", record->zi_object);
/*
* For the given object, initialize the range in bytes
*/
if (initialize_range(type, level, (char *)range, record) != 0)
goto err;
ziprintf(" objset: %llu\n", record->zi_objset);
ziprintf(" object: %llu\n", record->zi_object);
if (record->zi_start == 0 &&
record->zi_end == -1ULL)
ziprintf(" range: all\n");
else
ziprintf(" range: [%llu, %llu]\n", record->zi_start,
record->zi_end);
/*
* Copy the pool name
*/
(void) strcpy(poolname, dataset);
if ((slash = strchr(poolname, '/')) != NULL)
*slash = '\0';
ret = 0;
err:
return (ret);
}
int
translate_raw(const char *str, zinject_record_t *record)
{
/*
* A raw bookmark of the form objset:object:level:blkid, where each
* number is a hexadecimal value.
*/
if (sscanf(str, "%llx:%llx:%x:%llx", (u_longlong_t *)&record->zi_objset,
(u_longlong_t *)&record->zi_object, &record->zi_level,
(u_longlong_t *)&record->zi_start) != 4) {
(void) fprintf(stderr, "bad raw spec '%s': must be of the form "
"'objset:object:level:blkid'\n", str);
return (-1);
}
record->zi_end = record->zi_start;
return (0);
}
int
translate_device(const char *pool, const char *device, err_type_t label_type,
zinject_record_t *record)
{
char *end;
zpool_handle_t *zhp;
nvlist_t *tgt;
boolean_t isspare, iscache;
/*
* Given a device name or GUID, create an appropriate injection record
* with zi_guid set.
*/
if ((zhp = zpool_open(g_zfs, pool)) == NULL)
return (-1);
record->zi_guid = strtoull(device, &end, 0);
if (record->zi_guid == 0 || *end != '\0') {
tgt = zpool_find_vdev(zhp, device, &isspare, &iscache, NULL);
if (tgt == NULL) {
(void) fprintf(stderr, "cannot find device '%s' in "
"pool '%s'\n", device, pool);
zpool_close(zhp);
return (-1);
}
verify(nvlist_lookup_uint64(tgt, ZPOOL_CONFIG_GUID,
&record->zi_guid) == 0);
}
/*
* Device faults can take on three different forms:
* 1). delayed or hanging I/O
* 2). zfs label faults
* 3). generic disk faults
*/
if (record->zi_timer != 0) {
record->zi_cmd = ZINJECT_DELAY_IO;
} else if (label_type != TYPE_INVAL) {
record->zi_cmd = ZINJECT_LABEL_FAULT;
} else {
record->zi_cmd = ZINJECT_DEVICE_FAULT;
}
switch (label_type) {
default:
break;
case TYPE_LABEL_UBERBLOCK:
record->zi_start = offsetof(vdev_label_t, vl_uberblock[0]);
record->zi_end = record->zi_start + VDEV_UBERBLOCK_RING - 1;
break;
case TYPE_LABEL_NVLIST:
record->zi_start = offsetof(vdev_label_t, vl_vdev_phys);
record->zi_end = record->zi_start + VDEV_PHYS_SIZE - 1;
break;
case TYPE_LABEL_PAD1:
record->zi_start = offsetof(vdev_label_t, vl_pad1);
record->zi_end = record->zi_start + VDEV_PAD_SIZE - 1;
break;
case TYPE_LABEL_PAD2:
record->zi_start = offsetof(vdev_label_t, vl_be);
record->zi_end = record->zi_start + VDEV_PAD_SIZE - 1;
break;
}
zpool_close(zhp);
return (0);
}