/*
* storage_backend_disk.c: storage backend for disk handling
*
* Copyright (C) 2007-2016 Red Hat, Inc.
* Copyright (C) 2007-2008 Daniel P. Berrange
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* .
*
* Author: Daniel P. Berrange
*/
#include
#include
#include
#include
#include "dirname.h"
#include "virerror.h"
#include "virlog.h"
#include "storage_backend_disk.h"
#include "viralloc.h"
#include "vircommand.h"
#include "virfile.h"
#include "configmake.h"
#include "virstring.h"
#define VIR_FROM_THIS VIR_FROM_STORAGE
VIR_LOG_INIT("storage.storage_backend_disk");
#define SECTOR_SIZE 512
static int
virStorageBackendDiskMakeDataVol(virStoragePoolObjPtr pool,
char **const groups,
virStorageVolDefPtr vol)
{
char *tmp, *devpath, *partname;
/* Prepended path will be same for all partitions, so we can
* strip the path to form a reasonable pool-unique name
*/
if ((tmp = strrchr(groups[0], '/')))
partname = tmp + 1;
else
partname = groups[0];
if (vol == NULL) {
/* This is typically a reload/restart/refresh path where
* we're discovering the existing partitions for the pool
*/
if (VIR_ALLOC(vol) < 0)
return -1;
if (VIR_STRDUP(vol->name, partname) < 0 ||
VIR_APPEND_ELEMENT_COPY(pool->volumes.objs,
pool->volumes.count, vol) < 0) {
virStorageVolDefFree(vol);
return -1;
}
}
if (vol->target.path == NULL) {
if (VIR_STRDUP(devpath, groups[0]) < 0)
return -1;
/* Now figure out the stable path
*
* XXX this method is O(N) because it scans the pool target
* dir every time its run. Should figure out a more efficient
* way of doing this...
*/
vol->target.path = virStorageBackendStablePath(pool, devpath, true);
VIR_FREE(devpath);
if (vol->target.path == NULL)
return -1;
}
/* Enforce provided vol->name is the same as what parted created.
* We do this after filling target.path so that we have a chance at
* deleting the partition with this failure from CreateVol path
*/
if (STRNEQ(vol->name, partname)) {
virReportError(VIR_ERR_INVALID_ARG,
_("invalid partition name '%s', expected '%s'"),
vol->name, partname);
return -1;
}
if (vol->key == NULL) {
/* XXX base off a unique key of the underlying disk */
if (VIR_STRDUP(vol->key, vol->target.path) < 0)
return -1;
}
if (vol->source.extents == NULL) {
if (VIR_ALLOC(vol->source.extents) < 0)
return -1;
vol->source.nextent = 1;
if (virStrToLong_ull(groups[3], NULL, 10,
&vol->source.extents[0].start) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
"%s", _("cannot parse device start location"));
return -1;
}
if (virStrToLong_ull(groups[4], NULL, 10,
&vol->source.extents[0].end) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
"%s", _("cannot parse device end location"));
return -1;
}
if (VIR_STRDUP(vol->source.extents[0].path,
pool->def->source.devices[0].path) < 0)
return -1;
}
/* set partition type */
if (STREQ(groups[1], "normal"))
vol->source.partType = VIR_STORAGE_VOL_DISK_TYPE_PRIMARY;
else if (STREQ(groups[1], "logical"))
vol->source.partType = VIR_STORAGE_VOL_DISK_TYPE_LOGICAL;
else if (STREQ(groups[1], "extended"))
vol->source.partType = VIR_STORAGE_VOL_DISK_TYPE_EXTENDED;
else
vol->source.partType = VIR_STORAGE_VOL_DISK_TYPE_NONE;
vol->type = VIR_STORAGE_VOL_BLOCK;
/* Refresh allocation/capacity/perms
*
* For an extended partition, virStorageBackendUpdateVolInfo will
* return incorrect values for allocation and capacity, so use the
* extent information captured above instead.
*
* Also once a logical partition exists or another primary partition
* after an extended partition is created an open on the extended
* partition will fail, so pass the NOERROR flag and only error if a
* -1 was returned indicating some other error than an open error.
*/
if (vol->source.partType == VIR_STORAGE_VOL_DISK_TYPE_EXTENDED) {
if (virStorageBackendUpdateVolInfo(vol, false,
VIR_STORAGE_VOL_OPEN_DEFAULT |
VIR_STORAGE_VOL_OPEN_NOERROR,
0) == -1)
return -1;
vol->target.allocation = 0;
vol->target.capacity =
(vol->source.extents[0].end - vol->source.extents[0].start);
} else {
if (virStorageBackendUpdateVolInfo(vol, false,
VIR_STORAGE_VOL_OPEN_DEFAULT, 0) < 0)
return -1;
}
/* Find the extended partition and increase the allocation value */
if (vol->source.partType == VIR_STORAGE_VOL_DISK_TYPE_LOGICAL) {
size_t i;
for (i = 0; i < pool->volumes.count; i++) {
if (pool->volumes.objs[i]->source.partType ==
VIR_STORAGE_VOL_DISK_TYPE_EXTENDED) {
pool->volumes.objs[i]->target.allocation +=
vol->target.allocation;
break;
}
}
}
if (STRNEQ(groups[2], "metadata"))
pool->def->allocation += vol->target.allocation;
if (vol->source.extents[0].end > pool->def->capacity)
pool->def->capacity = vol->source.extents[0].end;
return 0;
}
static int
virStorageBackendDiskMakeFreeExtent(virStoragePoolObjPtr pool,
char **const groups)
{
virStoragePoolSourceDevicePtr dev = &pool->def->source.devices[0];
if (VIR_REALLOC_N(dev->freeExtents,
dev->nfreeExtent + 1) < 0)
return -1;
memset(dev->freeExtents +
dev->nfreeExtent, 0,
sizeof(dev->freeExtents[0]));
/* set type of free area */
if (STREQ(groups[1], "logical")) {
dev->freeExtents[dev->nfreeExtent].type = VIR_STORAGE_FREE_LOGICAL;
} else {
dev->freeExtents[dev->nfreeExtent].type = VIR_STORAGE_FREE_NORMAL;
}
if (virStrToLong_ull(groups[3], NULL, 10,
&dev->freeExtents[dev->nfreeExtent].start) < 0)
return -1; /* Don't bother to re-alloc freeExtents - it'll be free'd shortly */
if (virStrToLong_ull(groups[4], NULL, 10,
&dev->freeExtents[dev->nfreeExtent].end) < 0)
return -1; /* Don't bother to re-alloc freeExtents - it'll be free'd shortly */
/* first block reported as free, even if it is not */
if (dev->freeExtents[dev->nfreeExtent].start == 0)
dev->freeExtents[dev->nfreeExtent].start = SECTOR_SIZE;
pool->def->available +=
(dev->freeExtents[dev->nfreeExtent].end -
dev->freeExtents[dev->nfreeExtent].start);
if (dev->freeExtents[dev->nfreeExtent].end > pool->def->capacity)
pool->def->capacity = dev->freeExtents[dev->nfreeExtent].end;
dev->nfreeExtent++;
return 0;
}
struct virStorageBackendDiskPoolVolData {
virStoragePoolObjPtr pool;
virStorageVolDefPtr vol;
};
static int
virStorageBackendDiskMakeVol(size_t ntok ATTRIBUTE_UNUSED,
char **const groups,
void *opaque)
{
struct virStorageBackendDiskPoolVolData *data = opaque;
virStoragePoolObjPtr pool = data->pool;
/*
* Ignore normal+metadata, and logical+metadata partitions
* since they're basically internal book-keeping regions
* we have no control over. Do keep extended+metadata though
* because that's the MS-DOS extended partition region we
* need to be able to view/create/delete
*/
if ((STREQ(groups[1], "normal") ||
STREQ(groups[1], "logical")) &&
STREQ(groups[2], "metadata"))
return 0;
/* Remaining data / metadata parts get turn into volumes... */
if (STREQ(groups[2], "metadata") ||
STREQ(groups[2], "data")) {
virStorageVolDefPtr vol = data->vol;
if (vol) {
/* We're searching for a specific vol only */
if (vol->key) {
if (STRNEQ(vol->key, groups[0]))
return 0;
} else if (virStorageVolDefFindByKey(pool, groups[0]) != NULL) {
/* If no key, the volume must be newly created. If groups[0]
* isn't already a volume, assume it's the path we want */
return 0;
}
}
return virStorageBackendDiskMakeDataVol(pool, groups, vol);
} else if (STREQ(groups[2], "free")) {
/* ....or free space extents */
return virStorageBackendDiskMakeFreeExtent(pool, groups);
} else {
/* This code path should never happen unless someone changed
* libvirt_parthelper forgot to change this code */
return -1;
}
}
/* To get a list of partitions we run an external helper
* tool which then uses parted APIs. This is because
* parted's API is not compatible with libvirt's license
* but we really really want to use parted because the
* other options all suck :-)
*
* All the other storage backends run an external tool for
* listing volumes so this really isn't too much of a pain,
* and we can even ensure the output is friendly.
*/
static int
virStorageBackendDiskReadPartitions(virStoragePoolObjPtr pool,
virStorageVolDefPtr vol)
{
/*
* # libvirt_parthelper DEVICE
* /dev/sda1 normal data 32256 106928128 106896384
* /dev/sda2 normal data 106928640 100027629568 99920701440
* - normal metadata 100027630080 100030242304 2612736
*
*/
char *parthelper_path;
virCommandPtr cmd;
struct virStorageBackendDiskPoolVolData cbdata = {
.pool = pool,
.vol = vol,
};
int ret;
if (!(parthelper_path = virFileFindResource("libvirt_parthelper",
abs_topbuilddir "/src",
LIBEXECDIR)))
return -1;
cmd = virCommandNewArgList(parthelper_path,
pool->def->source.devices[0].path,
NULL);
/* Check for the presence of the part_separator='yes'. Pass this
* along to the libvirt_parthelper as option '-p'. This will cause
* libvirt_parthelper to append the "p" partition separator to
* the generated device name for a source device which ends with
* a non-numeric value (e.g. mpatha would generate mpathap#).
*/
if (pool->def->source.devices[0].part_separator ==
VIR_TRISTATE_BOOL_YES)
virCommandAddArg(cmd, "-p");
/* If a volume is passed, virStorageBackendDiskMakeVol only updates the
* pool allocation for that single volume.
*/
if (!vol)
pool->def->allocation = 0;
pool->def->capacity = pool->def->available = 0;
ret = virCommandRunNul(cmd,
6,
virStorageBackendDiskMakeVol,
&cbdata);
virCommandFree(cmd);
VIR_FREE(parthelper_path);
return ret;
}
static int
virStorageBackendDiskMakePoolGeometry(size_t ntok ATTRIBUTE_UNUSED,
char **const groups,
void *data)
{
virStoragePoolObjPtr pool = data;
virStoragePoolSourceDevicePtr device = &(pool->def->source.devices[0]);
if (virStrToLong_i(groups[0], NULL, 0, &device->geometry.cylinders) < 0 ||
virStrToLong_i(groups[1], NULL, 0, &device->geometry.heads) < 0 ||
virStrToLong_i(groups[2], NULL, 0, &device->geometry.sectors) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("Failed to create disk pool geometry"));
return -1;
}
return 0;
}
static int
virStorageBackendDiskReadGeometry(virStoragePoolObjPtr pool)
{
char *parthelper_path;
virCommandPtr cmd;
int ret;
if (!(parthelper_path = virFileFindResource("libvirt_parthelper",
abs_topbuilddir "/src",
LIBEXECDIR)))
return -1;
cmd = virCommandNewArgList(parthelper_path,
pool->def->source.devices[0].path,
"-g",
NULL);
ret = virCommandRunNul(cmd,
3,
virStorageBackendDiskMakePoolGeometry,
pool);
virCommandFree(cmd);
VIR_FREE(parthelper_path);
return ret;
}
static int
virStorageBackendDiskRefreshPool(virConnectPtr conn ATTRIBUTE_UNUSED,
virStoragePoolObjPtr pool)
{
VIR_FREE(pool->def->source.devices[0].freeExtents);
pool->def->source.devices[0].nfreeExtent = 0;
virFileWaitForDevices();
if (!virFileExists(pool->def->source.devices[0].path)) {
virReportError(VIR_ERR_INVALID_ARG,
_("device path '%s' doesn't exist"),
pool->def->source.devices[0].path);
return -1;
}
if (virStorageBackendDiskReadGeometry(pool) != 0)
return -1;
return virStorageBackendDiskReadPartitions(pool, NULL);
}
/**
* Check for a valid disk label (partition table) on device
*
* return: 0 - valid disk label found
* 1 - no or unrecognized disk label
* 2 - did not find the Partition Table type
* 3 - Partition Table type unknown
* <0 - error finding the disk label
*/
static int
virStorageBackendDiskFindLabel(const char* device)
{
const char *const args[] = {
device, "print", "--script", NULL,
};
virCommandPtr cmd = virCommandNew(PARTED);
char *output = NULL;
char *error = NULL;
char *start, *end;
int ret = -1;
virCommandAddArgSet(cmd, args);
virCommandAddEnvString(cmd, "LC_ALL=C");
virCommandSetOutputBuffer(cmd, &output);
virCommandSetErrorBuffer(cmd, &error);
/* if parted succeeds we have a valid partition table */
ret = virCommandRun(cmd, NULL);
if (ret < 0) {
if ((output && strstr(output, "unrecognised disk label")) ||
(error && strstr(error, "unrecognised disk label"))) {
ret = 1;
}
goto cleanup;
}
/* Search for "Partition Table:" in the output. If not present,
* then we cannot validate the partition table type.
*/
if (!(start = strstr(output, "Partition Table: ")) ||
!(end = strstr(start, "\n"))) {
VIR_DEBUG("Unable to find tag in output: %s", output);
ret = 2;
goto cleanup;
}
start += strlen("Partition Table: ");
*end = '\0';
/* on disk it's "msdos", but we document/use "dos" so deal with it here */
if (STREQ(start, "msdos"))
start += 2;
/* Make sure we know about this type */
if (virStoragePoolFormatDiskTypeFromString(start) < 0) {
ret = 3;
goto cleanup;
}
ret = 0;
cleanup:
virCommandFree(cmd);
VIR_FREE(output);
VIR_FREE(error);
return ret;
}
/**
* Determine whether the label on the disk is valid or in a known format
* for the purpose of rewriting the label during build or being able to
* start a pool on a device.
*
* When 'writelabel' is true, if we find a valid disk label on the device,
* then we shouldn't be attempting to write as the volume may contain
* data. Force the usage of the overwrite flag to the build command in
* order to be certain. When the disk label is unrecognized, then it
* should be safe to write.
*
* When 'writelabel' is false, only if we find a valid disk label on the
* device should we allow the start since for this path we won't be
* rewriting the label.
*
* Return: True if it's OK
* False if something's wrong
*/
static bool
virStorageBackendDiskValidLabel(const char *device,
bool writelabel)
{
bool valid = false;
int check;
check = virStorageBackendDiskFindLabel(device);
if (check == 1) {
if (writelabel)
valid = true;
else
virReportError(VIR_ERR_OPERATION_FAILED, "%s",
_("Unrecognized disk label found, requires build"));
} else if (check == 2) {
virReportError(VIR_ERR_OPERATION_FAILED, "%s",
_("Unable to determine Partition Type, "
"requires build --overwrite"));
} else if (check == 3) {
virReportError(VIR_ERR_OPERATION_FAILED, "%s",
_("Unknown Partition Type, requires build --overwrite"));
} else if (check < 0) {
virReportError(VIR_ERR_OPERATION_FAILED, "%s",
_("Error checking for disk label, failed to get "
"disk partition information"));
} else {
if (writelabel)
virReportError(VIR_ERR_OPERATION_INVALID, "%s",
_("Valid disk label already present, "
"requires --overwrite"));
else
valid = true;
}
return valid;
}
static int
virStorageBackendDiskStartPool(virConnectPtr conn ATTRIBUTE_UNUSED,
virStoragePoolObjPtr pool)
{
virFileWaitForDevices();
if (!virFileExists(pool->def->source.devices[0].path)) {
virReportError(VIR_ERR_INVALID_ARG,
_("device path '%s' doesn't exist"),
pool->def->source.devices[0].path);
return -1;
}
if (!virStorageBackendDiskValidLabel(pool->def->source.devices[0].path,
false))
return -1;
return 0;
}
/**
* Write a new partition table header
*/
static int
virStorageBackendDiskBuildPool(virConnectPtr conn ATTRIBUTE_UNUSED,
virStoragePoolObjPtr pool,
unsigned int flags)
{
bool ok_to_mklabel = false;
int ret = -1;
virCommandPtr cmd = NULL;
virCheckFlags(VIR_STORAGE_POOL_BUILD_OVERWRITE |
VIR_STORAGE_POOL_BUILD_NO_OVERWRITE, ret);
VIR_EXCLUSIVE_FLAGS_GOTO(VIR_STORAGE_POOL_BUILD_OVERWRITE,
VIR_STORAGE_POOL_BUILD_NO_OVERWRITE,
error);
if (flags & VIR_STORAGE_POOL_BUILD_OVERWRITE)
ok_to_mklabel = true;
else
ok_to_mklabel = virStorageBackendDiskValidLabel(
pool->def->source.devices[0].path,
true);
if (ok_to_mklabel) {
/* eg parted /dev/sda mklabel --script msdos */
int format = pool->def->source.format;
const char *fmt;
if (format == VIR_STORAGE_POOL_DISK_UNKNOWN)
format = pool->def->source.format = VIR_STORAGE_POOL_DISK_DOS;
if (format == VIR_STORAGE_POOL_DISK_DOS)
fmt = "msdos";
else
fmt = virStoragePoolFormatDiskTypeToString(format);
cmd = virCommandNewArgList(PARTED,
pool->def->source.devices[0].path,
"mklabel",
"--script",
fmt,
NULL);
ret = virCommandRun(cmd, NULL);
}
error:
virCommandFree(cmd);
return ret;
}
/**
* Decides what kind of partition type that should be created.
* Important when the partition table is of msdos type
*/
static int
virStorageBackendDiskPartTypeToCreate(virStoragePoolObjPtr pool)
{
if (pool->def->source.format == VIR_STORAGE_POOL_DISK_DOS) {
/* count primary and extended partitions,
can't be more than 3 to create a new primary partition */
size_t i;
int count = 0;
for (i = 0; i < pool->volumes.count; i++) {
int partType = pool->volumes.objs[i]->source.partType;
if (partType == VIR_STORAGE_VOL_DISK_TYPE_PRIMARY ||
partType == VIR_STORAGE_VOL_DISK_TYPE_EXTENDED)
count++;
}
if (count >= 4)
return VIR_STORAGE_VOL_DISK_TYPE_LOGICAL;
}
/* for all other cases, all partitions are primary */
return VIR_STORAGE_VOL_DISK_TYPE_PRIMARY;
}
static int
virStorageBackendDiskPartFormat(virStoragePoolObjPtr pool,
virStorageVolDefPtr vol,
char** partFormat)
{
size_t i;
if (pool->def->source.format == VIR_STORAGE_POOL_DISK_DOS) {
const char *partedFormat;
partedFormat = virStoragePartedFsTypeToString(vol->target.format);
if (partedFormat == NULL) {
virReportError(VIR_ERR_INTERNAL_ERROR,
"%s", _("Invalid partition type"));
return -1;
}
if (vol->target.format == VIR_STORAGE_VOL_DISK_EXTENDED) {
/* make sure we don't have a extended partition already */
for (i = 0; i < pool->volumes.count; i++) {
if (pool->volumes.objs[i]->source.partType ==
VIR_STORAGE_VOL_DISK_TYPE_EXTENDED) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("extended partition already exists"));
return -1;
}
}
if (VIR_STRDUP(*partFormat, partedFormat) < 0)
return -1;
} else {
/* create primary partition as long as it is possible
and after that check if an extended partition exists
to create logical partitions. */
/* XXX Only support one extended partition */
switch (virStorageBackendDiskPartTypeToCreate(pool)) {
case VIR_STORAGE_VOL_DISK_TYPE_PRIMARY:
if (virAsprintf(partFormat, "primary %s", partedFormat) < 0)
return -1;
break;
case VIR_STORAGE_VOL_DISK_TYPE_LOGICAL:
/* make sure we have a extended partition */
for (i = 0; i < pool->volumes.count; i++) {
if (pool->volumes.objs[i]->source.partType ==
VIR_STORAGE_VOL_DISK_TYPE_EXTENDED) {
if (virAsprintf(partFormat, "logical %s",
partedFormat) < 0)
return -1;
break;
}
}
if (i == pool->volumes.count) {
virReportError(VIR_ERR_INTERNAL_ERROR,
"%s", _("no extended partition found and no primary partition available"));
return -1;
}
break;
default:
virReportError(VIR_ERR_INTERNAL_ERROR,
"%s", _("unknown partition type"));
return -1;
}
}
} else {
if (VIR_STRDUP(*partFormat, "primary") < 0)
return -1;
}
return 0;
}
/**
* Aligns a new partition to nearest cylinder boundary
* when having a msdos partition table type
* to avoid any problem with already existing
* partitions
*/
static int
virStorageBackendDiskPartBoundaries(virStoragePoolObjPtr pool,
unsigned long long *start,
unsigned long long *end,
unsigned long long allocation)
{
size_t i;
int smallestExtent = -1;
unsigned long long smallestSize = 0;
unsigned long long extraBytes = 0;
unsigned long long alignedAllocation = allocation;
virStoragePoolSourceDevicePtr dev = &pool->def->source.devices[0];
unsigned long long cylinderSize = (unsigned long long)dev->geometry.heads *
dev->geometry.sectors * SECTOR_SIZE;
VIR_DEBUG("find free area: allocation %llu, cyl size %llu", allocation,
cylinderSize);
int partType = virStorageBackendDiskPartTypeToCreate(pool);
/* how many extra bytes we have since we allocate
aligned to the cylinder boundary */
extraBytes = cylinderSize - (allocation % cylinderSize);
for (i = 0; i < dev->nfreeExtent; i++) {
unsigned long long size =
dev->freeExtents[i].end -
dev->freeExtents[i].start;
unsigned long long neededSize = allocation;
if (pool->def->source.format == VIR_STORAGE_POOL_DISK_DOS) {
/* align to cylinder boundary */
neededSize += extraBytes;
if ((*start % cylinderSize) > extraBytes) {
/* add an extra cylinder if the offset can't fit within
the extra bytes we have */
neededSize += cylinderSize;
}
/* if we are creating a logical partition, we need one extra
block between partitions (or actually move start one block) */
if (partType == VIR_STORAGE_VOL_DISK_TYPE_LOGICAL)
size -= SECTOR_SIZE;
}
if (size > neededSize &&
(smallestSize == 0 ||
size < smallestSize)) {
/* for logical partition, the free extent
must be within a logical free area */
if (partType == VIR_STORAGE_VOL_DISK_TYPE_LOGICAL &&
dev->freeExtents[i].type != VIR_STORAGE_FREE_LOGICAL) {
continue;
/* for primary partition, the free extent
must not be within a logical free area */
} else if (partType == VIR_STORAGE_VOL_DISK_TYPE_PRIMARY &&
dev->freeExtents[i].type != VIR_STORAGE_FREE_NORMAL) {
continue;
}
smallestSize = size;
smallestExtent = i;
alignedAllocation = neededSize;
}
}
if (smallestExtent == -1) {
virReportError(VIR_ERR_INTERNAL_ERROR,
"%s", _("no large enough free extent"));
return -1;
}
VIR_DEBUG("aligned alloc %llu", alignedAllocation);
*start = dev->freeExtents[smallestExtent].start;
if (partType == VIR_STORAGE_VOL_DISK_TYPE_LOGICAL) {
/* for logical partition, skip one block */
*start += SECTOR_SIZE;
}
*end = *start + alignedAllocation;
if (pool->def->source.format == VIR_STORAGE_POOL_DISK_DOS) {
/* adjust our allocation if start is not at a cylinder boundary */
*end -= (*start % cylinderSize);
}
/* counting in bytes, we want the last byte of the current sector */
*end -= 1;
VIR_DEBUG("final aligned start %llu, end %llu", *start, *end);
return 0;
}
/* virStorageBackendDiskDeleteVol
* @conn: Pointer to a libvirt connection
* @pool: Pointer to the storage pool
* @vol: Pointer to the volume definition
* @flags: flags (unused for now)
*
* This API will remove the disk volume partition either from direct
* API call or as an error path during creation when the partition
* name provided during create doesn't match the name read from
* virStorageBackendDiskReadPartitions.
*
* For a device mapper device, device respresentation is dependant upon
* device mapper configuration, but the general rule of thumb is that at
* creation if a device name ends with a number, then a partition separator
* "p" is added to the created name; otherwise, if the device name doesn't
* end with a number, then there is no partition separator. This name is
* what ends up in the vol->target.path. This ends up being a link to a
* /dev/mapper/dm-# device which cannot be used in the algorithm to determine
* which partition to remove, but a properly handled target.path can be.
*
* For non device mapper devices, just need to resolve the link of the
* vol->target.path in order to get the path.
*
* Returns 0 on success, -1 on failure with error message set.
*/
static int
virStorageBackendDiskDeleteVol(virConnectPtr conn,
virStoragePoolObjPtr pool,
virStorageVolDefPtr vol,
unsigned int flags)
{
char *part_num = NULL;
char *devpath = NULL;
char *dev_name;
char *src_path = pool->def->source.devices[0].path;
char *srcname = last_component(src_path);
virCommandPtr cmd = NULL;
bool isDevMapperDevice;
int rc = -1;
virCheckFlags(0, -1);
if (!vol->target.path) {
virReportError(VIR_ERR_INVALID_ARG,
_("volume target path empty for source path '%s'"),
src_path);
return -1;
}
/* NB: This is the corollary to the algorithm in libvirt_parthelper
* (parthelper.c) that is used to generate the target.path name
* for use by libvirt. Changes to either, need to be reflected
* in both places */
isDevMapperDevice = virIsDevMapperDevice(vol->target.path);
if (isDevMapperDevice) {
dev_name = last_component(vol->target.path);
} else {
if (virFileResolveLink(vol->target.path, &devpath) < 0) {
virReportSystemError(errno,
_("Couldn't read volume target path '%s'"),
vol->target.path);
goto cleanup;
}
dev_name = last_component(devpath);
}
VIR_DEBUG("dev_name=%s, srcname=%s", dev_name, srcname);
if (!STRPREFIX(dev_name, srcname)) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Volume path '%s' did not start with parent "
"pool source device name."), dev_name);
goto cleanup;
}
part_num = dev_name + strlen(srcname);
/* For device mapper and we have a partition character 'p' as the
* current character, let's move beyond that before checking part_num */
if (isDevMapperDevice && *part_num == 'p')
part_num++;
if (*part_num == 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("cannot parse partition number from target "
"'%s'"), dev_name);
goto cleanup;
}
/* eg parted /dev/sda rm 2 or /dev/mapper/mpathc rm 2 */
cmd = virCommandNewArgList(PARTED,
src_path,
"rm",
"--script",
part_num,
NULL);
if (virCommandRun(cmd, NULL) < 0)
goto cleanup;
/* Refreshing the pool is the easiest option as LOGICAL and EXTENDED
* partition allocation/capacity management is handled within
* virStorageBackendDiskMakeDataVol and trying to redo that logic
* here is pointless
*/
virStoragePoolObjClearVols(pool);
if (virStorageBackendDiskRefreshPool(conn, pool) < 0)
goto cleanup;
rc = 0;
cleanup:
VIR_FREE(devpath);
virCommandFree(cmd);
return rc;
}
static int
virStorageBackendDiskCreateVol(virConnectPtr conn,
virStoragePoolObjPtr pool,
virStorageVolDefPtr vol)
{
int res = -1;
char *partFormat = NULL;
unsigned long long startOffset = 0, endOffset = 0;
virCommandPtr cmd = virCommandNewArgList(PARTED,
pool->def->source.devices[0].path,
"mkpart",
"--script",
NULL);
if (vol->target.encryption != NULL) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
"%s", _("storage pool does not support encrypted "
"volumes"));
goto cleanup;
}
if (virStorageBackendDiskPartFormat(pool, vol, &partFormat) != 0)
goto cleanup;
virCommandAddArg(cmd, partFormat);
if (virStorageBackendDiskPartBoundaries(pool, &startOffset,
&endOffset,
vol->target.capacity) != 0) {
goto cleanup;
}
virCommandAddArgFormat(cmd, "%lluB", startOffset);
virCommandAddArgFormat(cmd, "%lluB", endOffset);
if (virCommandRun(cmd, NULL) < 0)
goto cleanup;
/* wait for device node to show up */
virFileWaitForDevices();
/* Blow away free extent info, as we're about to re-populate it */
VIR_FREE(pool->def->source.devices[0].freeExtents);
pool->def->source.devices[0].nfreeExtent = 0;
/* Specifying a target path is meaningless */
VIR_FREE(vol->target.path);
/* Fetch actual extent info, generate key */
if (virStorageBackendDiskReadPartitions(pool, vol) < 0) {
/* Best effort to remove the partition. Ignore any errors
* since we could be calling this with vol->target.path == NULL
*/
virErrorPtr save_err = virSaveLastError();
ignore_value(virStorageBackendDiskDeleteVol(conn, pool, vol, 0));
virSetError(save_err);
virFreeError(save_err);
goto cleanup;
}
res = 0;
cleanup:
VIR_FREE(partFormat);
virCommandFree(cmd);
return res;
}
static int
virStorageBackendDiskBuildVolFrom(virConnectPtr conn,
virStoragePoolObjPtr pool,
virStorageVolDefPtr vol,
virStorageVolDefPtr inputvol,
unsigned int flags)
{
virStorageBackendBuildVolFrom build_func;
build_func = virStorageBackendGetBuildVolFromFunction(vol, inputvol);
if (!build_func)
return -1;
return build_func(conn, pool, vol, inputvol, flags);
}
static int
virStorageBackendDiskVolWipe(virConnectPtr conn,
virStoragePoolObjPtr pool,
virStorageVolDefPtr vol,
unsigned int algorithm,
unsigned int flags)
{
if (vol->source.partType != VIR_STORAGE_VOL_DISK_TYPE_EXTENDED)
return virStorageBackendVolWipeLocal(conn, pool, vol, algorithm, flags);
/* Wiping an extended partition is not support */
virReportError(VIR_ERR_NO_SUPPORT,
_("cannot wipe extended partition '%s'"),
vol->target.path);
return -1;
}
virStorageBackend virStorageBackendDisk = {
.type = VIR_STORAGE_POOL_DISK,
.startPool = virStorageBackendDiskStartPool,
.buildPool = virStorageBackendDiskBuildPool,
.refreshPool = virStorageBackendDiskRefreshPool,
.createVol = virStorageBackendDiskCreateVol,
.deleteVol = virStorageBackendDiskDeleteVol,
.buildVolFrom = virStorageBackendDiskBuildVolFrom,
.uploadVol = virStorageBackendVolUploadLocal,
.downloadVol = virStorageBackendVolDownloadLocal,
.wipeVol = virStorageBackendDiskVolWipe,
};