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1390c26847
libvirt/src/storage/storage_backend.c
Ján Tomko 1390c26847 safezero: fall back to writing zeroes even when resizing 
Remove the resize flag and use the same code path for all callers.
This flag was added by commit 18f0316 to allow virStorageFileResize
use 'safezero' while preserving the behavior.

Explicitly return -2 when a fallback to a different method should
be done, to make the code path more obvious.

Fail immediately when ftruncate fails in the mmap method,
as we did before commit 18f0316.
2015-01-09 13:48:23 +01:00

2028 lines
62 KiB
C
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/*
* storage_backend.c: internal storage driver backend contract
*
* Copyright (C) 2007-2014 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
* <http://www.gnu.org/licenses/>.
*
* Author: Daniel P. Berrange <berrange@redhat.com>
*/
#include <config.h>
#include <string.h>
#include <stdio.h>
#include <regex.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/param.h>
#include <dirent.h>
#include "dirname.h"
#ifdef __linux__
# include <sys/ioctl.h>
# include <linux/fs.h>
# ifndef FS_NOCOW_FL
# define FS_NOCOW_FL 0x00800000 /* Do not cow file */
# endif
#endif
#if WITH_SELINUX
# include <selinux/selinux.h>
#endif
#include "datatypes.h"
#include "virerror.h"
#include "viralloc.h"
#include "internal.h"
#include "secret_conf.h"
#include "viruuid.h"
#include "virstoragefile.h"
#include "storage_backend.h"
#include "virlog.h"
#include "virfile.h"
#include "stat-time.h"
#include "virstring.h"
#include "virxml.h"
#include "fdstream.h"
#if WITH_STORAGE_LVM
# include "storage_backend_logical.h"
#endif
#if WITH_STORAGE_ISCSI
# include "storage_backend_iscsi.h"
#endif
#if WITH_STORAGE_SCSI
# include "storage_backend_scsi.h"
#endif
#if WITH_STORAGE_MPATH
# include "storage_backend_mpath.h"
#endif
#if WITH_STORAGE_DISK
# include "storage_backend_disk.h"
#endif
#if WITH_STORAGE_DIR
# include "storage_backend_fs.h"
#endif
#if WITH_STORAGE_RBD
# include "storage_backend_rbd.h"
#endif
#if WITH_STORAGE_SHEEPDOG
# include "storage_backend_sheepdog.h"
#endif
#if WITH_STORAGE_GLUSTER
# include "storage_backend_gluster.h"
#endif
#if WITH_STORAGE_ZFS
# include "storage_backend_zfs.h"
#endif
#define VIR_FROM_THIS VIR_FROM_STORAGE
VIR_LOG_INIT("storage.storage_backend");
static virStorageBackendPtr backends[] = {
#if WITH_STORAGE_DIR
&virStorageBackendDirectory,
#endif
#if WITH_STORAGE_FS
&virStorageBackendFileSystem,
&virStorageBackendNetFileSystem,
#endif
#if WITH_STORAGE_LVM
&virStorageBackendLogical,
#endif
#if WITH_STORAGE_ISCSI
&virStorageBackendISCSI,
#endif
#if WITH_STORAGE_SCSI
&virStorageBackendSCSI,
#endif
#if WITH_STORAGE_MPATH
&virStorageBackendMpath,
#endif
#if WITH_STORAGE_DISK
&virStorageBackendDisk,
#endif
#if WITH_STORAGE_RBD
&virStorageBackendRBD,
#endif
#if WITH_STORAGE_SHEEPDOG
&virStorageBackendSheepdog,
#endif
#if WITH_STORAGE_GLUSTER
&virStorageBackendGluster,
#endif
#if WITH_STORAGE_ZFS
&virStorageBackendZFS,
#endif
NULL
};
static virStorageFileBackendPtr fileBackends[] = {
#if WITH_STORAGE_FS
&virStorageFileBackendFile,
&virStorageFileBackendBlock,
#endif
#if WITH_STORAGE_GLUSTER
&virStorageFileBackendGluster,
#endif
NULL
};
enum {
TOOL_QEMU_IMG,
TOOL_KVM_IMG,
TOOL_QCOW_CREATE,
};
#define READ_BLOCK_SIZE_DEFAULT (1024 * 1024)
#define WRITE_BLOCK_SIZE_DEFAULT (4 * 1024)
static int ATTRIBUTE_NONNULL(2)
virStorageBackendCopyToFD(virStorageVolDefPtr vol,
virStorageVolDefPtr inputvol,
int fd,
unsigned long long *total,
bool want_sparse)
{
int inputfd = -1;
int amtread = -1;
int ret = 0;
size_t rbytes = READ_BLOCK_SIZE_DEFAULT;
int wbytes = 0;
int interval;
char *zerobuf = NULL;
char *buf = NULL;
struct stat st;
if ((inputfd = open(inputvol->target.path, O_RDONLY)) < 0) {
ret = -errno;
virReportSystemError(errno,
_("could not open input path '%s'"),
inputvol->target.path);
goto cleanup;
}
#ifdef __linux__
if (ioctl(fd, BLKBSZGET, &wbytes) < 0)
wbytes = 0;
#endif
if ((wbytes == 0) && fstat(fd, &st) == 0)
wbytes = st.st_blksize;
if (wbytes < WRITE_BLOCK_SIZE_DEFAULT)
wbytes = WRITE_BLOCK_SIZE_DEFAULT;
if (VIR_ALLOC_N(zerobuf, wbytes) < 0) {
ret = -errno;
goto cleanup;
}
if (VIR_ALLOC_N(buf, rbytes) < 0) {
ret = -errno;
goto cleanup;
}
while (amtread != 0) {
int amtleft;
if (*total < rbytes)
rbytes = *total;
if ((amtread = saferead(inputfd, buf, rbytes)) < 0) {
ret = -errno;
virReportSystemError(errno,
_("failed reading from file '%s'"),
inputvol->target.path);
goto cleanup;
}
*total -= amtread;
/* Loop over amt read in 512 byte increments, looking for sparse
* blocks */
amtleft = amtread;
do {
interval = ((wbytes > amtleft) ? amtleft : wbytes);
int offset = amtread - amtleft;
if (want_sparse && memcmp(buf+offset, zerobuf, interval) == 0) {
if (lseek(fd, interval, SEEK_CUR) < 0) {
ret = -errno;
virReportSystemError(errno,
_("cannot extend file '%s'"),
vol->target.path);
goto cleanup;
}
} else if (safewrite(fd, buf+offset, interval) < 0) {
ret = -errno;
virReportSystemError(errno,
_("failed writing to file '%s'"),
vol->target.path);
goto cleanup;
}
} while ((amtleft -= interval) > 0);
}
if (fdatasync(fd) < 0) {
ret = -errno;
virReportSystemError(errno, _("cannot sync data to file '%s'"),
vol->target.path);
goto cleanup;
}
if (VIR_CLOSE(inputfd) < 0) {
ret = -errno;
virReportSystemError(errno,
_("cannot close file '%s'"),
inputvol->target.path);
goto cleanup;
}
inputfd = -1;
cleanup:
VIR_FORCE_CLOSE(inputfd);
VIR_FREE(zerobuf);
VIR_FREE(buf);
return ret;
}
static int
virStorageBackendCreateBlockFrom(virConnectPtr conn ATTRIBUTE_UNUSED,
virStoragePoolObjPtr pool ATTRIBUTE_UNUSED,
virStorageVolDefPtr vol,
virStorageVolDefPtr inputvol,
unsigned int flags)
{
int fd = -1;
int ret = -1;
unsigned long long remain;
struct stat st;
gid_t gid;
uid_t uid;
virCheckFlags(VIR_STORAGE_VOL_CREATE_PREALLOC_METADATA, -1);
if (flags & VIR_STORAGE_VOL_CREATE_PREALLOC_METADATA) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("metadata preallocation is not supported for block "
"volumes"));
goto cleanup;
}
if ((fd = open(vol->target.path, O_RDWR)) < 0) {
virReportSystemError(errno,
_("cannot create path '%s'"),
vol->target.path);
goto cleanup;
}
remain = vol->target.allocation;
if (inputvol) {
int res = virStorageBackendCopyToFD(vol, inputvol,
fd, &remain, false);
if (res < 0)
goto cleanup;
}
if (fstat(fd, &st) == -1) {
virReportSystemError(errno, _("stat of '%s' failed"),
vol->target.path);
goto cleanup;
}
uid = (vol->target.perms->uid != st.st_uid) ? vol->target.perms->uid
: (uid_t) -1;
gid = (vol->target.perms->gid != st.st_gid) ? vol->target.perms->gid
: (gid_t) -1;
if (((uid != (uid_t) -1) || (gid != (gid_t) -1))
&& (fchown(fd, uid, gid) < 0)) {
virReportSystemError(errno,
_("cannot chown '%s' to (%u, %u)"),
vol->target.path, (unsigned int) uid,
(unsigned int) gid);
goto cleanup;
}
if (fchmod(fd, vol->target.perms->mode) < 0) {
virReportSystemError(errno,
_("cannot set mode of '%s' to %04o"),
vol->target.path, vol->target.perms->mode);
goto cleanup;
}
if (VIR_CLOSE(fd) < 0) {
virReportSystemError(errno,
_("cannot close file '%s'"),
vol->target.path);
goto cleanup;
}
fd = -1;
ret = 0;
cleanup:
VIR_FORCE_CLOSE(fd);
return ret;
}
static int
createRawFile(int fd, virStorageVolDefPtr vol,
virStorageVolDefPtr inputvol)
{
bool need_alloc = true;
int ret = 0;
unsigned long long remain;
/* Seek to the final size, so the capacity is available upfront
* for progress reporting */
if (ftruncate(fd, vol->target.capacity) < 0) {
ret = -errno;
virReportSystemError(errno,
_("cannot extend file '%s'"),
vol->target.path);
goto cleanup;
}
/* Avoid issues with older kernel's <linux/fs.h> namespace pollution. */
#if HAVE_FALLOCATE - 0
/* Try to preallocate all requested disk space, but fall back to
* other methods if this fails with ENOSYS or EOPNOTSUPP. If allocation
* is 0 (or less than 0), then fallocate will fail with EINVAL.
* NOTE: do not use posix_fallocate; posix_fallocate falls back
* to writing zeroes block by block in case fallocate isn't
* available, and since we're going to copy data from another
* file it doesn't make sense to write the file twice. */
if (vol->target.allocation) {
if (fallocate(fd, 0, 0, vol->target.allocation) == 0) {
need_alloc = false;
} else if (errno != ENOSYS && errno != EOPNOTSUPP) {
ret = -errno;
virReportSystemError(errno,
_("cannot allocate %llu bytes in file '%s'"),
vol->target.allocation, vol->target.path);
goto cleanup;
}
}
#endif
remain = vol->target.allocation;
if (inputvol) {
/* allow zero blocks to be skipped if we've requested sparse
* allocation (allocation < capacity) or we have already
* been able to allocate the required space. */
bool want_sparse = !need_alloc ||
(vol->target.allocation < inputvol->target.capacity);
ret = virStorageBackendCopyToFD(vol, inputvol, fd, &remain, want_sparse);
if (ret < 0)
goto cleanup;
}
if (remain && need_alloc) {
if (safezero(fd, vol->target.allocation - remain, remain) < 0) {
ret = -errno;
virReportSystemError(errno, _("cannot fill file '%s'"),
vol->target.path);
goto cleanup;
}
}
if (fsync(fd) < 0) {
ret = -errno;
virReportSystemError(errno, _("cannot sync data to file '%s'"),
vol->target.path);
goto cleanup;
}
cleanup:
return ret;
}
int
virStorageBackendCreateRaw(virConnectPtr conn ATTRIBUTE_UNUSED,
virStoragePoolObjPtr pool,
virStorageVolDefPtr vol,
virStorageVolDefPtr inputvol,
unsigned int flags)
{
int ret = -1;
int fd = -1;
int operation_flags;
virCheckFlags(VIR_STORAGE_VOL_CREATE_PREALLOC_METADATA, -1);
if (flags & VIR_STORAGE_VOL_CREATE_PREALLOC_METADATA) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("metadata preallocation is not supported for raw "
"volumes"));
goto cleanup;
}
if (vol->target.encryption != NULL) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("storage pool does not support encrypted volumes"));
goto cleanup;
}
operation_flags = VIR_FILE_OPEN_FORCE_MODE | VIR_FILE_OPEN_FORCE_OWNER;
if (pool->def->type == VIR_STORAGE_POOL_NETFS)
operation_flags |= VIR_FILE_OPEN_FORK;
if ((fd = virFileOpenAs(vol->target.path,
O_RDWR | O_CREAT | O_EXCL,
vol->target.perms->mode,
vol->target.perms->uid,
vol->target.perms->gid,
operation_flags)) < 0) {
virReportSystemError(-fd,
_("Failed to create file '%s'"),
vol->target.path);
goto cleanup;
}
if (vol->target.nocow) {
#ifdef __linux__
int attr;
/* Set NOCOW flag. This is an optimisation for btrfs.
* The FS_IOC_SETFLAGS ioctl return value will be ignored since any
* failure of this operation should not block the volume creation.
*/
if (ioctl(fd, FS_IOC_GETFLAGS, &attr) < 0) {
virReportSystemError(errno, "%s", _("Failed to get fs flags"));
} else {
attr |= FS_NOCOW_FL;
if (ioctl(fd, FS_IOC_SETFLAGS, &attr) < 0) {
virReportSystemError(errno, "%s",
_("Failed to set NOCOW flag"));
}
}
#endif
}
if ((ret = createRawFile(fd, vol, inputvol)) < 0)
/* createRawFile already reported the exact error. */
ret = -1;
cleanup:
VIR_FORCE_CLOSE(fd);
return ret;
}
static int
virStorageGenerateSecretUUID(virConnectPtr conn,
unsigned char *uuid)
{
unsigned attempt;
for (attempt = 0; attempt < 65536; attempt++) {
virSecretPtr tmp;
if (virUUIDGenerate(uuid) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("unable to generate uuid"));
return -1;
}
tmp = conn->secretDriver->secretLookupByUUID(conn, uuid);
if (tmp == NULL)
return 0;
virObjectUnref(tmp);
}
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("too many conflicts when generating a uuid"));
return -1;
}
static int
virStorageGenerateQcowEncryption(virConnectPtr conn,
virStorageVolDefPtr vol)
{
virSecretDefPtr def = NULL;
virBuffer buf = VIR_BUFFER_INITIALIZER;
virStorageEncryptionPtr enc;
virStorageEncryptionSecretPtr enc_secret = NULL;
virSecretPtr secret = NULL;
char *xml;
unsigned char value[VIR_STORAGE_QCOW_PASSPHRASE_SIZE];
int ret = -1;
if (conn->secretDriver == NULL ||
conn->secretDriver->secretLookupByUUID == NULL ||
conn->secretDriver->secretDefineXML == NULL ||
conn->secretDriver->secretSetValue == NULL) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("secret storage not supported"));
goto cleanup;
}
enc = vol->target.encryption;
if (enc->nsecrets != 0) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("secrets already defined"));
goto cleanup;
}
if (VIR_ALLOC(enc_secret) < 0 || VIR_REALLOC_N(enc->secrets, 1) < 0 ||
VIR_ALLOC(def) < 0)
goto cleanup;
def->ephemeral = false;
def->private = false;
if (virStorageGenerateSecretUUID(conn, def->uuid) < 0)
goto cleanup;
def->usage_type = VIR_SECRET_USAGE_TYPE_VOLUME;
if (VIR_STRDUP(def->usage.volume, vol->target.path) < 0)
goto cleanup;
xml = virSecretDefFormat(def);
virSecretDefFree(def);
def = NULL;
if (xml == NULL)
goto cleanup;
secret = conn->secretDriver->secretDefineXML(conn, xml, 0);
if (secret == NULL) {
VIR_FREE(xml);
goto cleanup;
}
VIR_FREE(xml);
if (virStorageGenerateQcowPassphrase(value) < 0)
goto cleanup;
if (conn->secretDriver->secretSetValue(secret, value, sizeof(value), 0) < 0)
goto cleanup;
enc_secret->type = VIR_STORAGE_ENCRYPTION_SECRET_TYPE_PASSPHRASE;
memcpy(enc_secret->uuid, secret->uuid, VIR_UUID_BUFLEN);
enc->format = VIR_STORAGE_ENCRYPTION_FORMAT_QCOW;
enc->secrets[0] = enc_secret; /* Space for secrets[0] allocated above */
enc_secret = NULL;
enc->nsecrets = 1;
ret = 0;
cleanup:
if (secret != NULL) {
if (ret != 0 &&
conn->secretDriver->secretUndefine != NULL)
conn->secretDriver->secretUndefine(secret);
virObjectUnref(secret);
}
virBufferFreeAndReset(&buf);
virSecretDefFree(def);
VIR_FREE(enc_secret);
return ret;
}
static int
virStorageBackendCreateExecCommand(virStoragePoolObjPtr pool,
virStorageVolDefPtr vol,
virCommandPtr cmd)
{
struct stat st;
gid_t gid;
uid_t uid;
bool filecreated = false;
if ((pool->def->type == VIR_STORAGE_POOL_NETFS)
&& (((geteuid() == 0)
&& (vol->target.perms->uid != (uid_t) -1)
&& (vol->target.perms->uid != 0))
|| ((vol->target.perms->gid != (gid_t) -1)
&& (vol->target.perms->gid != getegid())))) {
virCommandSetUID(cmd, vol->target.perms->uid);
virCommandSetGID(cmd, vol->target.perms->gid);
if (virCommandRun(cmd, NULL) == 0) {
/* command was successfully run, check if the file was created */
if (stat(vol->target.path, &st) >= 0)
filecreated = true;
}
}
/* don't change uid/gid if we retry */
virCommandSetUID(cmd, -1);
virCommandSetGID(cmd, -1);
if (!filecreated) {
if (virCommandRun(cmd, NULL) < 0)
return -1;
if (stat(vol->target.path, &st) < 0) {
virReportSystemError(errno,
_("failed to create %s"), vol->target.path);
return -1;
}
}
uid = (vol->target.perms->uid != st.st_uid) ? vol->target.perms->uid
: (uid_t) -1;
gid = (vol->target.perms->gid != st.st_gid) ? vol->target.perms->gid
: (gid_t) -1;
if (((uid != (uid_t) -1) || (gid != (gid_t) -1))
&& (chown(vol->target.path, uid, gid) < 0)) {
virReportSystemError(errno,
_("cannot chown %s to (%u, %u)"),
vol->target.path, (unsigned int) uid,
(unsigned int) gid);
return -1;
}
if (chmod(vol->target.path, vol->target.perms->mode) < 0) {
virReportSystemError(errno,
_("cannot set mode of '%s' to %04o"),
vol->target.path, vol->target.perms->mode);
return -1;
}
return 0;
}
enum {
QEMU_IMG_BACKING_FORMAT_NONE = 0,
QEMU_IMG_BACKING_FORMAT_FLAG,
QEMU_IMG_BACKING_FORMAT_OPTIONS,
QEMU_IMG_BACKING_FORMAT_OPTIONS_COMPAT,
};
static bool
virStorageBackendQemuImgSupportsCompat(const char *qemuimg)
{
bool ret = false;
char *output;
virCommandPtr cmd = NULL;
cmd = virCommandNewArgList(qemuimg, "create", "-o", "?", "-f", "qcow2",
"/dev/null", NULL);
virCommandAddEnvString(cmd, "LC_ALL=C");
virCommandSetOutputBuffer(cmd, &output);
if (virCommandRun(cmd, NULL) < 0)
goto cleanup;
if (strstr(output, "\ncompat "))
ret = true;
cleanup:
virCommandFree(cmd);
VIR_FREE(output);
return ret;
}
static int
virStorageBackendQEMUImgBackingFormat(const char *qemuimg)
{
char *help = NULL;
char *start;
char *end;
char *tmp;
int ret = -1;
int exitstatus;
virCommandPtr cmd = virCommandNewArgList(qemuimg, "-h", NULL);
virCommandAddEnvString(cmd, "LC_ALL=C");
virCommandSetOutputBuffer(cmd, &help);
virCommandClearCaps(cmd);
/* qemuimg doesn't return zero exit status on -h,
* therefore we need to provide pointer for storing
* exit status, although we don't parse it any later */
if (virCommandRun(cmd, &exitstatus) < 0)
goto cleanup;
if ((start = strstr(help, " create ")) == NULL ||
(end = strstr(start, "\n")) == NULL) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("unable to parse qemu-img output '%s'"),
help);
goto cleanup;
}
if (((tmp = strstr(start, "-F fmt")) && tmp < end) ||
((tmp = strstr(start, "-F backing_fmt")) && tmp < end)) {
ret = QEMU_IMG_BACKING_FORMAT_FLAG;
} else if ((tmp = strstr(start, "[-o options]")) && tmp < end) {
if (virStorageBackendQemuImgSupportsCompat(qemuimg))
ret = QEMU_IMG_BACKING_FORMAT_OPTIONS_COMPAT;
else
ret = QEMU_IMG_BACKING_FORMAT_OPTIONS;
} else {
ret = QEMU_IMG_BACKING_FORMAT_NONE;
}
cleanup:
virCommandFree(cmd);
VIR_FREE(help);
return ret;
}
static int
virStorageBackendCreateQemuImgOpts(char **opts,
const char *backingType,
bool encryption,
bool preallocate,
int format,
const char *compat,
bool nocow,
virBitmapPtr features)
{
virBuffer buf = VIR_BUFFER_INITIALIZER;
bool b;
size_t i;
if (backingType)
virBufferAsprintf(&buf, "backing_fmt=%s,", backingType);
if (encryption)
virBufferAddLit(&buf, "encryption=on,");
if (preallocate)
virBufferAddLit(&buf, "preallocation=metadata,");
if (nocow)
virBufferAddLit(&buf, "nocow=on,");
if (compat)
virBufferAsprintf(&buf, "compat=%s,", compat);
if (features && format == VIR_STORAGE_FILE_QCOW2) {
for (i = 0; i < VIR_STORAGE_FILE_FEATURE_LAST; i++) {
ignore_value(virBitmapGetBit(features, i, &b));
if (b) {
switch ((virStorageFileFeature) i) {
case VIR_STORAGE_FILE_FEATURE_LAZY_REFCOUNTS:
if (STREQ_NULLABLE(compat, "0.10")) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
_("Feature %s not supported with compat"
" level %s"),
virStorageFileFeatureTypeToString(i),
compat);
goto error;
}
break;
/* coverity[dead_error_begin] */
case VIR_STORAGE_FILE_FEATURE_LAST:
;
}
virBufferAsprintf(&buf, "%s,",
virStorageFileFeatureTypeToString(i));
}
}
}
virBufferTrim(&buf, ",", -1);
if (virBufferCheckError(&buf) < 0)
goto error;
*opts = virBufferContentAndReset(&buf);
return 0;
error:
virBufferFreeAndReset(&buf);
return -1;
}
virCommandPtr
virStorageBackendCreateQemuImgCmd(virConnectPtr conn,
virStoragePoolObjPtr pool,
virStorageVolDefPtr vol,
virStorageVolDefPtr inputvol,
unsigned int flags,
const char *create_tool,
int imgformat)
{
virCommandPtr cmd = NULL;
bool do_encryption = (vol->target.encryption != NULL);
unsigned long long int size_arg;
bool preallocate = !!(flags & VIR_STORAGE_VOL_CREATE_PREALLOC_METADATA);
const char *type;
const char *backingType = NULL;
const char *inputPath = NULL;
const char *inputType = NULL;
const char *compat = vol->target.compat;
char *opts = NULL;
bool convert = false;
bool backing = false;
virCheckFlags(VIR_STORAGE_VOL_CREATE_PREALLOC_METADATA, NULL);
/* Treat output block devices as 'raw' format */
type = virStorageFileFormatTypeToString(vol->type == VIR_STORAGE_VOL_BLOCK ?
VIR_STORAGE_FILE_RAW :
vol->target.format);
if (!type) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("unknown storage vol type %d"),
vol->target.format);
return NULL;
}
if (preallocate && vol->target.format != VIR_STORAGE_FILE_QCOW2) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("metadata preallocation only available with qcow2"));
return NULL;
}
if (vol->target.compat && vol->target.format != VIR_STORAGE_FILE_QCOW2) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("compatibility option only available with qcow2"));
return NULL;
}
if (vol->target.features && vol->target.format != VIR_STORAGE_FILE_QCOW2) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("format features only available with qcow2"));
return NULL;
}
if (inputvol) {
if (!(inputPath = inputvol->target.path)) {
virReportError(VIR_ERR_INVALID_ARG, "%s",
_("missing input volume target path"));
return NULL;
}
inputType = virStorageFileFormatTypeToString(inputvol->type == VIR_STORAGE_VOL_BLOCK ?
VIR_STORAGE_FILE_RAW :
inputvol->target.format);
if (!inputType) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("unknown storage vol type %d"),
inputvol->target.format);
return NULL;
}
}
if (vol->target.backingStore) {
int accessRetCode = -1;
char *absolutePath = NULL;
backingType = virStorageFileFormatTypeToString(vol->target.backingStore->format);
if (preallocate) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("metadata preallocation conflicts with backing"
" store"));
return NULL;
}
/* XXX: Not strictly required: qemu-img has an option a different
* backing store, not really sure what use it serves though, and it
* may cause issues with lvm. Untested essentially.
*/
if (inputvol && inputvol->target.backingStore &&
STRNEQ_NULLABLE(inputvol->target.backingStore->path,
vol->target.backingStore->path)) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("a different backing store cannot be specified."));
return NULL;
}
if (backingType == NULL) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("unknown storage vol backing store type %d"),
vol->target.backingStore->format);
return NULL;
}
/* Convert relative backing store paths to absolute paths for access
* validation.
*/
if ('/' != *(vol->target.backingStore->path) &&
virAsprintf(&absolutePath, "%s/%s", pool->def->target.path,
vol->target.backingStore->path) < 0)
return NULL;
accessRetCode = access(absolutePath ? absolutePath
: vol->target.backingStore->path, R_OK);
VIR_FREE(absolutePath);
if (accessRetCode != 0) {
virReportSystemError(errno,
_("inaccessible backing store volume %s"),
vol->target.backingStore->path);
return NULL;
}
}
if (do_encryption) {
virStorageEncryptionPtr enc;
if (vol->target.format != VIR_STORAGE_FILE_QCOW &&
vol->target.format != VIR_STORAGE_FILE_QCOW2) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
_("qcow volume encryption unsupported with "
"volume format %s"), type);
return NULL;
}
enc = vol->target.encryption;
if (enc->format != VIR_STORAGE_ENCRYPTION_FORMAT_QCOW &&
enc->format != VIR_STORAGE_ENCRYPTION_FORMAT_DEFAULT) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
_("unsupported volume encryption format %d"),
vol->target.encryption->format);
return NULL;
}
if (enc->nsecrets > 1) {
virReportError(VIR_ERR_XML_ERROR, "%s",
_("too many secrets for qcow encryption"));
return NULL;
}
if (enc->format == VIR_STORAGE_ENCRYPTION_FORMAT_DEFAULT ||
enc->nsecrets == 0) {
if (virStorageGenerateQcowEncryption(conn, vol) < 0)
return NULL;
}
}
/* Size in KB */
size_arg = VIR_DIV_UP(vol->target.capacity, 1024);
cmd = virCommandNew(create_tool);
convert = !!inputvol;
backing = !inputvol && vol->target.backingStore;
if (convert)
virCommandAddArgList(cmd, "convert", "-f", inputType, "-O", type, NULL);
else
virCommandAddArgList(cmd, "create", "-f", type, NULL);
if (backing)
virCommandAddArgList(cmd, "-b", vol->target.backingStore->path, NULL);
if (imgformat >= QEMU_IMG_BACKING_FORMAT_OPTIONS) {
if (vol->target.format == VIR_STORAGE_FILE_QCOW2 && !compat &&
imgformat == QEMU_IMG_BACKING_FORMAT_OPTIONS_COMPAT)
compat = "0.10";
if (virStorageBackendCreateQemuImgOpts(&opts,
backing ? backingType : NULL,
do_encryption, preallocate,
vol->target.format,
compat,
vol->target.nocow,
vol->target.features) < 0) {
virCommandFree(cmd);
return NULL;
}
if (opts)
virCommandAddArgList(cmd, "-o", opts, NULL);
VIR_FREE(opts);
} else {
if (backing) {
if (imgformat == QEMU_IMG_BACKING_FORMAT_FLAG)
virCommandAddArgList(cmd, "-F", backingType, NULL);
else
VIR_DEBUG("Unable to set backing store format for %s with %s",
vol->target.path, create_tool);
}
if (do_encryption)
virCommandAddArg(cmd, "-e");
}
if (convert)
virCommandAddArg(cmd, inputPath);
virCommandAddArg(cmd, vol->target.path);
if (!convert)
virCommandAddArgFormat(cmd, "%lluK", size_arg);
return cmd;
}
static int
virStorageBackendCreateQemuImg(virConnectPtr conn,
virStoragePoolObjPtr pool,
virStorageVolDefPtr vol,
virStorageVolDefPtr inputvol,
unsigned int flags)
{
int ret = -1;
char *create_tool;
int imgformat;
virCommandPtr cmd;
virCheckFlags(VIR_STORAGE_VOL_CREATE_PREALLOC_METADATA, -1);
/* KVM is usually ahead of qemu on features, so try that first */
create_tool = virFindFileInPath("kvm-img");
if (!create_tool)
create_tool = virFindFileInPath("qemu-img");
if (!create_tool) {
virReportError(VIR_ERR_INTERNAL_ERROR,
"%s", _("unable to find kvm-img or qemu-img"));
return -1;
}
imgformat = virStorageBackendQEMUImgBackingFormat(create_tool);
if (imgformat < 0)
goto cleanup;
cmd = virStorageBackendCreateQemuImgCmd(conn, pool, vol, inputvol, flags,
create_tool, imgformat);
if (!cmd)
goto cleanup;
ret = virStorageBackendCreateExecCommand(pool, vol, cmd);
virCommandFree(cmd);
cleanup:
VIR_FREE(create_tool);
return ret;
}
/*
* Xen removed the fully-functional qemu-img, and replaced it
* with a partially functional qcow-create. Go figure ??!?
*/
static int
virStorageBackendCreateQcowCreate(virConnectPtr conn ATTRIBUTE_UNUSED,
virStoragePoolObjPtr pool,
virStorageVolDefPtr vol,
virStorageVolDefPtr inputvol,
unsigned int flags)
{
int ret;
char *size;
virCommandPtr cmd;
virCheckFlags(VIR_STORAGE_VOL_CREATE_PREALLOC_METADATA, -1);
if (flags & VIR_STORAGE_VOL_CREATE_PREALLOC_METADATA) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("metadata preallocation is not supported with "
"qcow-create"));
return -1;
}
if (inputvol) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("cannot copy from volume with qcow-create"));
return -1;
}
if (vol->target.format != VIR_STORAGE_FILE_QCOW2) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("unsupported storage vol type %d"),
vol->target.format);
return -1;
}
if (vol->target.backingStore != NULL) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("copy-on-write image not supported with "
"qcow-create"));
return -1;
}
if (vol->target.encryption != NULL) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
"%s", _("encrypted volumes not supported with "
"qcow-create"));
return -1;
}
/* Size in MB - yes different units to qemu-img :-( */
if (virAsprintf(&size, "%llu",
VIR_DIV_UP(vol->target.capacity, (1024 * 1024))) < 0)
return -1;
cmd = virCommandNewArgList("qcow-create", size, vol->target.path, NULL);
ret = virStorageBackendCreateExecCommand(pool, vol, cmd);
virCommandFree(cmd);
VIR_FREE(size);
return ret;
}
virStorageBackendBuildVolFrom
virStorageBackendFSImageToolTypeToFunc(int tool_type)
{
switch (tool_type) {
case TOOL_KVM_IMG:
case TOOL_QEMU_IMG:
return virStorageBackendCreateQemuImg;
case TOOL_QCOW_CREATE:
return virStorageBackendCreateQcowCreate;
default:
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Unknown file create tool type '%d'."),
tool_type);
}
return NULL;
}
int
virStorageBackendFindFSImageTool(char **tool)
{
int tool_type = -1;
char *tmp = NULL;
if ((tmp = virFindFileInPath("kvm-img")) != NULL) {
tool_type = TOOL_KVM_IMG;
} else if ((tmp = virFindFileInPath("qemu-img")) != NULL) {
tool_type = TOOL_QEMU_IMG;
} else if ((tmp = virFindFileInPath("qcow-create")) != NULL) {
tool_type = TOOL_QCOW_CREATE;
}
if (tool)
*tool = tmp;
else
VIR_FREE(tmp);
return tool_type;
}
virStorageBackendBuildVolFrom
virStorageBackendGetBuildVolFromFunction(virStorageVolDefPtr vol,
virStorageVolDefPtr inputvol)
{
int tool_type;
if (!inputvol)
return NULL;
/* If either volume is a non-raw file vol, we need to use an external
* tool for converting
*/
if ((vol->type == VIR_STORAGE_VOL_FILE &&
vol->target.format != VIR_STORAGE_FILE_RAW) ||
(inputvol->type == VIR_STORAGE_VOL_FILE &&
inputvol->target.format != VIR_STORAGE_FILE_RAW)) {
if ((tool_type = virStorageBackendFindFSImageTool(NULL)) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("creation of non-raw file images is "
"not supported without qemu-img."));
return NULL;
}
return virStorageBackendFSImageToolTypeToFunc(tool_type);
}
if (vol->type == VIR_STORAGE_VOL_BLOCK)
return virStorageBackendCreateBlockFrom;
else
return virStorageBackendCreateRaw;
}
virStorageBackendPtr
virStorageBackendForType(int type)
{
size_t i;
for (i = 0; backends[i]; i++)
if (backends[i]->type == type)
return backends[i];
virReportError(VIR_ERR_INTERNAL_ERROR,
_("missing backend for pool type %d (%s)"),
type, NULLSTR(virStoragePoolTypeToString(type)));
return NULL;
}
virStorageFileBackendPtr
virStorageFileBackendForTypeInternal(int type,
int protocol,
bool report)
{
size_t i;
for (i = 0; fileBackends[i]; i++) {
if (fileBackends[i]->type == type) {
if (type == VIR_STORAGE_TYPE_NETWORK &&
fileBackends[i]->protocol != protocol)
continue;
return fileBackends[i];
}
}
if (!report)
return NULL;
if (type == VIR_STORAGE_TYPE_NETWORK) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("missing storage backend for network files "
"using %s protocol"),
virStorageNetProtocolTypeToString(protocol));
} else {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("missing storage backend for '%s' storage"),
virStorageTypeToString(type));
}
return NULL;
}
virStorageFileBackendPtr
virStorageFileBackendForType(int type,
int protocol)
{
return virStorageFileBackendForTypeInternal(type, protocol, true);
}
struct diskType {
int part_table_type;
unsigned short offset;
unsigned short length;
unsigned long long magic;
};
static struct diskType const disk_types[] = {
{ VIR_STORAGE_POOL_DISK_LVM2, 0x218, 8, 0x31303020324D564CULL },
{ VIR_STORAGE_POOL_DISK_GPT, 0x200, 8, 0x5452415020494645ULL },
{ VIR_STORAGE_POOL_DISK_DVH, 0x0, 4, 0x41A9E50BULL },
{ VIR_STORAGE_POOL_DISK_MAC, 0x0, 2, 0x5245ULL },
{ VIR_STORAGE_POOL_DISK_BSD, 0x40, 4, 0x82564557ULL },
{ VIR_STORAGE_POOL_DISK_SUN, 0x1fc, 2, 0xBEDAULL },
/*
* NOTE: pc98 is funky; the actual signature is 0x55AA (just like dos), so
* we can't use that. At the moment I'm relying on the "dummy" IPL
* bootloader data that comes from parted. Luckily, the chances of running
* into a pc98 machine running libvirt are approximately nil.
*/
/*{ 0x1fe, 2, 0xAA55UL },*/
{ VIR_STORAGE_POOL_DISK_PC98, 0x0, 8, 0x314C5049000000CBULL },
/*
* NOTE: the order is important here; some other disk types (like GPT and
* and PC98) also have 0x55AA at this offset. For that reason, the DOS
* one must be the last one.
*/
{ VIR_STORAGE_POOL_DISK_DOS, 0x1fe, 2, 0xAA55ULL },
{ -1, 0x0, 0, 0x0ULL },
};
static int
virStorageBackendDetectBlockVolFormatFD(virStorageSourcePtr target,
int fd)
{
size_t i;
off_t start;
unsigned char buffer[1024];
ssize_t bytes;
/* make sure to set the target format "unknown" to begin with */
target->format = VIR_STORAGE_POOL_DISK_UNKNOWN;
start = lseek(fd, 0, SEEK_SET);
if (start < 0) {
virReportSystemError(errno,
_("cannot seek to beginning of file '%s'"),
target->path);
return -1;
}
bytes = saferead(fd, buffer, sizeof(buffer));
if (bytes < 0) {
virReportSystemError(errno,
_("cannot read beginning of file '%s'"),
target->path);
return -1;
}
for (i = 0; disk_types[i].part_table_type != -1; i++) {
if (disk_types[i].offset + disk_types[i].length > bytes)
continue;
if (memcmp(buffer+disk_types[i].offset, &disk_types[i].magic,
disk_types[i].length) == 0) {
target->format = disk_types[i].part_table_type;
break;
}
}
return 0;
}
/*
* Allows caller to silently ignore files with improper mode
*
* Returns -1 on error. If VIR_STORAGE_VOL_OPEN_NOERROR is passed, we
* return -2 if file mode is unexpected or the volume is a dangling
* symbolic link.
*/
int
virStorageBackendVolOpen(const char *path, struct stat *sb,
unsigned int flags)
{
int fd, mode = 0;
char *base = last_component(path);
bool noerror = (flags & VIR_STORAGE_VOL_OPEN_NOERROR);
if (lstat(path, sb) < 0) {
if (errno == ENOENT) {
if (noerror) {
VIR_WARN("ignoring missing file '%s'", path);
return -2;
}
virReportError(VIR_ERR_NO_STORAGE_VOL,
_("no storage vol with matching path '%s'"),
path);
return -1;
}
virReportSystemError(errno,
_("cannot stat file '%s'"),
path);
return -1;
}
if (S_ISFIFO(sb->st_mode)) {
if (noerror) {
VIR_WARN("ignoring FIFO '%s'", path);
return -2;
}
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Volume path '%s' is a FIFO"), path);
return -1;
} else if (S_ISSOCK(sb->st_mode)) {
if (noerror) {
VIR_WARN("ignoring socket '%s'", path);
return -2;
}
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Volume path '%s' is a socket"), path);
return -1;
}
/* O_NONBLOCK should only matter during open() for fifos and
* sockets, which we already filtered; but using it prevents a
* TOCTTOU race. However, later on we will want to read() the
* header from this fd, and virFileRead* routines require a
* blocking fd, so fix it up after verifying we avoided a
* race. */
if ((fd = open(path, O_RDONLY|O_NONBLOCK|O_NOCTTY)) < 0) {
if ((errno == ENOENT || errno == ELOOP) &&
S_ISLNK(sb->st_mode) && noerror) {
VIR_WARN("ignoring dangling symlink '%s'", path);
return -2;
}
if (errno == ENOENT && noerror) {
VIR_WARN("ignoring missing file '%s'", path);
return -2;
}
virReportSystemError(errno, _("cannot open volume '%s'"), path);
return -1;
}
if (fstat(fd, sb) < 0) {
virReportSystemError(errno, _("cannot stat file '%s'"), path);
VIR_FORCE_CLOSE(fd);
return -1;
}
if (S_ISREG(sb->st_mode)) {
mode = VIR_STORAGE_VOL_OPEN_REG;
} else if (S_ISCHR(sb->st_mode)) {
mode = VIR_STORAGE_VOL_OPEN_CHAR;
} else if (S_ISBLK(sb->st_mode)) {
mode = VIR_STORAGE_VOL_OPEN_BLOCK;
} else if (S_ISDIR(sb->st_mode)) {
mode = VIR_STORAGE_VOL_OPEN_DIR;
if (STREQ(base, ".") ||
STREQ(base, "..")) {
VIR_FORCE_CLOSE(fd);
if (noerror) {
VIR_INFO("Skipping special dir '%s'", base);
return -2;
}
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Cannot use volume path '%s'"), path);
return -1;
}
} else {
VIR_FORCE_CLOSE(fd);
if (noerror) {
VIR_WARN("ignoring unexpected type for file '%s'", path);
return -2;
}
virReportError(VIR_ERR_INTERNAL_ERROR,
_("unexpected type for file '%s'"), path);
return -1;
}
if (virSetBlocking(fd, true) < 0) {
VIR_FORCE_CLOSE(fd);
virReportSystemError(errno, _("unable to set blocking mode for '%s'"),
path);
return -1;
}
if (!(mode & flags)) {
VIR_FORCE_CLOSE(fd);
if (noerror) {
VIR_INFO("Skipping volume '%s'", path);
return -2;
}
virReportError(VIR_ERR_INTERNAL_ERROR,
_("unexpected storage mode for '%s'"), path);
return -1;
}
return fd;
}
int
virStorageBackendUpdateVolTargetInfo(virStorageSourcePtr target,
bool updateCapacity,
bool withBlockVolFormat,
unsigned int openflags)
{
int ret, fd = -1;
struct stat sb;
if ((ret = virStorageBackendVolOpen(target->path, &sb, openflags)) < 0)
goto cleanup;
fd = ret;
if ((ret = virStorageBackendUpdateVolTargetInfoFD(target, fd, &sb,
updateCapacity)) < 0)
goto cleanup;
if (withBlockVolFormat) {
if ((ret = virStorageBackendDetectBlockVolFormatFD(target, fd)) < 0)
goto cleanup;
}
cleanup:
VIR_FORCE_CLOSE(fd);
return ret;
}
int
virStorageBackendUpdateVolInfo(virStorageVolDefPtr vol,
bool updateCapacity,
bool withBlockVolFormat,
unsigned int openflags)
{
int ret;
if ((ret = virStorageBackendUpdateVolTargetInfo(&vol->target,
updateCapacity,
withBlockVolFormat,
openflags)) < 0)
return ret;
if (vol->target.backingStore &&
(ret = virStorageBackendUpdateVolTargetInfo(vol->target.backingStore,
updateCapacity,
withBlockVolFormat,
VIR_STORAGE_VOL_OPEN_DEFAULT |
VIR_STORAGE_VOL_OPEN_NOERROR) < 0))
return ret;
return 0;
}
/*
* virStorageBackendUpdateVolTargetInfoFD:
* @target: target definition ptr of volume to update
* @fd: fd of storage volume to update, via virStorageBackendOpenVol*, or -1
* @sb: details about file (must match @fd, if that is provided)
* @updateCapacity: If true, updated capacity info will be stored
*
* Returns 0 for success, -1 on a legitimate error condition.
*/
int
virStorageBackendUpdateVolTargetInfoFD(virStorageSourcePtr target,
int fd,
struct stat *sb,
bool updateCapacity)
{
#if WITH_SELINUX
security_context_t filecon = NULL;
#endif
if (S_ISREG(sb->st_mode)) {
#ifndef WIN32
target->allocation = (unsigned long long)sb->st_blocks *
(unsigned long long)DEV_BSIZE;
#else
target->allocation = sb->st_size;
#endif
/* Regular files may be sparse, so logical size (capacity) is not same
* as actual allocation above
*/
if (updateCapacity)
target->capacity = sb->st_size;
} else if (S_ISDIR(sb->st_mode)) {
target->allocation = 0;
if (updateCapacity)
target->capacity = 0;
} else if (fd >= 0) {
off_t end;
/* XXX this is POSIX compliant, but doesn't work for CHAR files,
* only BLOCK. There is a Linux specific ioctl() for getting
* size of both CHAR / BLOCK devices we should check for in
* configure
*/
end = lseek(fd, 0, SEEK_END);
if (end == (off_t)-1) {
virReportSystemError(errno,
_("cannot seek to end of file '%s'"),
target->path);
return -1;
}
target->allocation = end;
if (updateCapacity)
target->capacity = end;
}
if (!target->perms && VIR_ALLOC(target->perms) < 0)
return -1;
target->perms->mode = sb->st_mode & S_IRWXUGO;
target->perms->uid = sb->st_uid;
target->perms->gid = sb->st_gid;
if (!target->timestamps && VIR_ALLOC(target->timestamps) < 0)
return -1;
target->timestamps->atime = get_stat_atime(sb);
target->timestamps->btime = get_stat_birthtime(sb);
target->timestamps->ctime = get_stat_ctime(sb);
target->timestamps->mtime = get_stat_mtime(sb);
VIR_FREE(target->perms->label);
#if WITH_SELINUX
/* XXX: make this a security driver call */
if (fd >= 0) {
if (fgetfilecon_raw(fd, &filecon) == -1) {
if (errno != ENODATA && errno != ENOTSUP) {
virReportSystemError(errno,
_("cannot get file context of '%s'"),
target->path);
return -1;
}
} else {
if (VIR_STRDUP(target->perms->label, filecon) < 0) {
freecon(filecon);
return -1;
}
freecon(filecon);
}
}
#endif
return 0;
}
/*
* Given a volume path directly in /dev/XXX, iterate over the
* entries in the directory pool->def->target.path and find the
* first symlink pointing to the volume path.
*
* If, the target.path is /dev/, then return the original volume
* path.
*
* If no symlink is found, then return the original volume path
*
* Typically target.path is one of the /dev/disk/by-XXX dirs
* with stable paths.
*
* If 'loop' is true, we use a timeout loop to give dynamic paths
* a change to appear.
*/
char *
virStorageBackendStablePath(virStoragePoolObjPtr pool,
const char *devpath,
bool loop)
{
DIR *dh;
struct dirent *dent;
char *stablepath;
int opentries = 0;
int retry = 0;
int direrr;
/* Short circuit if pool has no target, or if its /dev */
if (pool->def->target.path == NULL ||
STREQ(pool->def->target.path, "/dev") ||
STREQ(pool->def->target.path, "/dev/"))
goto ret_strdup;
/* Skip whole thing for a pool which isn't in /dev
* so we don't mess filesystem/dir based pools
*/
if (!STRPREFIX(pool->def->target.path, "/dev"))
goto ret_strdup;
/* Logical pools are under /dev but already have stable paths */
if (pool->def->type == VIR_STORAGE_POOL_LOGICAL)
goto ret_strdup;
/* We loop here because /dev/disk/by-{id,path} may not have existed
* before we started this operation, so we have to give it some time to
* get created.
*/
reopen:
if ((dh = opendir(pool->def->target.path)) == NULL) {
opentries++;
if (loop && errno == ENOENT && opentries < 50) {
usleep(100 * 1000);
goto reopen;
}
virReportSystemError(errno,
_("cannot read dir '%s'"),
pool->def->target.path);
return NULL;
}
/* The pool is pointing somewhere like /dev/disk/by-path
* or /dev/disk/by-id, so we need to check all symlinks in
* the target directory and figure out which one points
* to this device node.
*
* And it might need some time till the stable path shows
* up, so add timeout to retry here. Ignore readdir failures,
* since we have a fallback.
*/
retry:
while ((direrr = virDirRead(dh, &dent, NULL)) > 0) {
if (dent->d_name[0] == '.')
continue;
if (virAsprintf(&stablepath, "%s/%s",
pool->def->target.path,
dent->d_name) == -1) {
closedir(dh);
return NULL;
}
if (virFileLinkPointsTo(stablepath, devpath)) {
closedir(dh);
return stablepath;
}
VIR_FREE(stablepath);
}
if (!direrr && loop && ++retry < 100) {
usleep(100 * 1000);
goto retry;
}
closedir(dh);
ret_strdup:
/* Couldn't find any matching stable link so give back
* the original non-stable dev path
*/
ignore_value(VIR_STRDUP(stablepath, devpath));
return stablepath;
}
int
virStorageBackendVolUploadLocal(virConnectPtr conn ATTRIBUTE_UNUSED,
virStoragePoolObjPtr pool ATTRIBUTE_UNUSED,
virStorageVolDefPtr vol,
virStreamPtr stream,
unsigned long long offset,
unsigned long long len,
unsigned int flags)
{
virCheckFlags(0, -1);
/* Not using O_CREAT because the file is required to already exist at
* this point */
return virFDStreamOpenBlockDevice(stream, vol->target.path,
offset, len, O_WRONLY);
}
int
virStorageBackendVolDownloadLocal(virConnectPtr conn ATTRIBUTE_UNUSED,
virStoragePoolObjPtr pool ATTRIBUTE_UNUSED,
virStorageVolDefPtr vol,
virStreamPtr stream,
unsigned long long offset,
unsigned long long len,
unsigned int flags)
{
virCheckFlags(0, -1);
return virFDStreamOpenBlockDevice(stream, vol->target.path,
offset, len, O_RDONLY);
}
/* If the volume we're wiping is already a sparse file, we simply
* truncate and extend it to its original size, filling it with
* zeroes. This behavior is guaranteed by POSIX:
*
* http://www.opengroup.org/onlinepubs/9699919799/functions/ftruncate.html
*
* If fildes refers to a regular file, the ftruncate() function shall
* cause the size of the file to be truncated to length. If the size
* of the file previously exceeded length, the extra data shall no
* longer be available to reads on the file. If the file previously
* was smaller than this size, ftruncate() shall increase the size of
* the file. If the file size is increased, the extended area shall
* appear as if it were zero-filled.
*/
static int
virStorageBackendVolZeroSparseFileLocal(virStorageVolDefPtr vol,
off_t size,
int fd)
{
int ret = -1;
ret = ftruncate(fd, 0);
if (ret == -1) {
virReportSystemError(errno,
_("Failed to truncate volume with "
"path '%s' to 0 bytes"),
vol->target.path);
return ret;
}
ret = ftruncate(fd, size);
if (ret == -1) {
virReportSystemError(errno,
_("Failed to truncate volume with "
"path '%s' to %ju bytes"),
vol->target.path, (uintmax_t)size);
}
return ret;
}
static int
virStorageBackendWipeExtentLocal(virStorageVolDefPtr vol,
int fd,
off_t extent_start,
off_t extent_length,
char *writebuf,
size_t writebuf_length,
size_t *bytes_wiped)
{
int ret = -1, written = 0;
off_t remaining = 0;
size_t write_size = 0;
VIR_DEBUG("extent logical start: %ju len: %ju",
(uintmax_t)extent_start, (uintmax_t)extent_length);
if ((ret = lseek(fd, extent_start, SEEK_SET)) < 0) {
virReportSystemError(errno,
_("Failed to seek to position %ju in volume "
"with path '%s'"),
(uintmax_t)extent_start, vol->target.path);
goto cleanup;
}
remaining = extent_length;
while (remaining > 0) {
write_size = (writebuf_length < remaining) ? writebuf_length : remaining;
written = safewrite(fd, writebuf, write_size);
if (written < 0) {
virReportSystemError(errno,
_("Failed to write %zu bytes to "
"storage volume with path '%s'"),
write_size, vol->target.path);
goto cleanup;
}
*bytes_wiped += written;
remaining -= written;
}
if (fdatasync(fd) < 0) {
ret = -errno;
virReportSystemError(errno,
_("cannot sync data to volume with path '%s'"),
vol->target.path);
goto cleanup;
}
VIR_DEBUG("Wrote %zu bytes to volume with path '%s'",
*bytes_wiped, vol->target.path);
ret = 0;
cleanup:
return ret;
}
int
virStorageBackendVolWipeLocal(virConnectPtr conn ATTRIBUTE_UNUSED,
virStoragePoolObjPtr pool ATTRIBUTE_UNUSED,
virStorageVolDefPtr vol,
unsigned int algorithm,
unsigned int flags)
{
int ret = -1, fd = -1;
struct stat st;
char *writebuf = NULL;
size_t bytes_wiped = 0;
virCommandPtr cmd = NULL;
virCheckFlags(0, -1);
VIR_DEBUG("Wiping volume with path '%s' and algorithm %u",
vol->target.path, algorithm);
fd = open(vol->target.path, O_RDWR);
if (fd == -1) {
virReportSystemError(errno,
_("Failed to open storage volume with path '%s'"),
vol->target.path);
goto cleanup;
}
if (fstat(fd, &st) == -1) {
virReportSystemError(errno,
_("Failed to stat storage volume with path '%s'"),
vol->target.path);
goto cleanup;
}
if (algorithm != VIR_STORAGE_VOL_WIPE_ALG_ZERO) {
const char *alg_char ATTRIBUTE_UNUSED = NULL;
switch (algorithm) {
case VIR_STORAGE_VOL_WIPE_ALG_NNSA:
alg_char = "nnsa";
break;
case VIR_STORAGE_VOL_WIPE_ALG_DOD:
alg_char = "dod";
break;
case VIR_STORAGE_VOL_WIPE_ALG_BSI:
alg_char = "bsi";
break;
case VIR_STORAGE_VOL_WIPE_ALG_GUTMANN:
alg_char = "gutmann";
break;
case VIR_STORAGE_VOL_WIPE_ALG_SCHNEIER:
alg_char = "schneier";
break;
case VIR_STORAGE_VOL_WIPE_ALG_PFITZNER7:
alg_char = "pfitzner7";
break;
case VIR_STORAGE_VOL_WIPE_ALG_PFITZNER33:
alg_char = "pfitzner33";
break;
case VIR_STORAGE_VOL_WIPE_ALG_RANDOM:
alg_char = "random";
break;
default:
virReportError(VIR_ERR_INVALID_ARG,
_("unsupported algorithm %d"),
algorithm);
}
cmd = virCommandNew(SCRUB);
virCommandAddArgList(cmd, "-f", "-p", alg_char,
vol->target.path, NULL);
if (virCommandRun(cmd, NULL) < 0)
goto cleanup;
ret = 0;
goto cleanup;
} else {
if (S_ISREG(st.st_mode) && st.st_blocks < (st.st_size / DEV_BSIZE)) {
ret = virStorageBackendVolZeroSparseFileLocal(vol, st.st_size, fd);
} else {
if (VIR_ALLOC_N(writebuf, st.st_blksize) < 0)
goto cleanup;
ret = virStorageBackendWipeExtentLocal(vol,
fd,
0,
vol->target.allocation,
writebuf,
st.st_blksize,
&bytes_wiped);
}
}
cleanup:
virCommandFree(cmd);
VIR_FREE(writebuf);
VIR_FORCE_CLOSE(fd);
return ret;
}
#ifdef GLUSTER_CLI
int
virStorageBackendFindGlusterPoolSources(const char *host,
int pooltype,
virStoragePoolSourceListPtr list)
{
char *outbuf = NULL;
virCommandPtr cmd = NULL;
xmlDocPtr doc = NULL;
xmlXPathContextPtr ctxt = NULL;
xmlNodePtr *nodes = NULL;
virStoragePoolSource *src = NULL;
size_t i;
int nnodes;
int rc;
int ret = -1;
cmd = virCommandNewArgList(GLUSTER_CLI,
"--xml",
"--log-file=/dev/null",
"volume", "info", "all", NULL);
virCommandAddArgFormat(cmd, "--remote-host=%s", host);
virCommandSetOutputBuffer(cmd, &outbuf);
if (virCommandRun(cmd, &rc) < 0)
goto cleanup;
if (rc != 0) {
VIR_INFO("failed to query host '%s' for gluster volumes: %s",
host, outbuf);
ret = 0;
goto cleanup;
}
if (!(doc = virXMLParseStringCtxt(outbuf, _("(gluster_cli_output)"),
&ctxt)))
goto cleanup;
if ((nnodes = virXPathNodeSet("//volumes/volume", ctxt, &nodes)) <= 0) {
VIR_INFO("no gluster volumes available on '%s'", host);
ret = 0;
goto cleanup;
}
for (i = 0; i < nnodes; i++) {
ctxt->node = nodes[i];
if (!(src = virStoragePoolSourceListNewSource(list)))
goto cleanup;
if (!(src->dir = virXPathString("string(//name)", ctxt))) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("failed to extract gluster volume name"));
goto cleanup;
}
if (VIR_ALLOC_N(src->hosts, 1) < 0)
goto cleanup;
src->nhost = 1;
if (VIR_STRDUP(src->hosts[0].name, host) < 0)
goto cleanup;
src->format = pooltype;
}
ret = 0;
cleanup:
VIR_FREE(nodes);
xmlXPathFreeContext(ctxt);
xmlFreeDoc(doc);
VIR_FREE(outbuf);
virCommandFree(cmd);
return ret;
}
#else /* #ifdef GLUSTER_CLI */
int
virStorageBackendFindGlusterPoolSources(const char *host ATTRIBUTE_UNUSED,
int pooltype ATTRIBUTE_UNUSED,
virStoragePoolSourceListPtr list ATTRIBUTE_UNUSED)
{
VIR_INFO("gluster cli tool not installed");
return 0;
}
#endif /* #ifdef GLUSTER_CLI */
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