storage_backend.c 47.8 KB
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/*
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 * storage_backend.c: internal storage driver backend contract
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 *
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 * Copyright (C) 2007-2011 Red Hat, Inc.
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 * 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA
 *
 * Author: Daniel P. Berrange <berrange@redhat.com>
 */

#include <config.h>

#include <string.h>
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#include <stdio.h>
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#if HAVE_REGEX_H
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# include <regex.h>
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#endif
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#include <sys/types.h>
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#include <sys/wait.h>
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#include <unistd.h>
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#include <fcntl.h>
#include <stdint.h>
#include <sys/stat.h>
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#include <sys/param.h>
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#include <dirent.h>
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#ifdef __linux__
# include <sys/ioctl.h>
# include <linux/fs.h>
#endif
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#if HAVE_SELINUX
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# include <selinux/selinux.h>
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#endif
47

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#include "datatypes.h"
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#include "virterror_internal.h"
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#include "util.h"
#include "memory.h"
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#include "internal.h"
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#include "secret_conf.h"
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#include "uuid.h"
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#include "storage_file.h"
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#include "storage_backend.h"
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#include "logging.h"
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#include "files.h"
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#include "command.h"
60

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#if WITH_STORAGE_LVM
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# include "storage_backend_logical.h"
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#endif
#if WITH_STORAGE_ISCSI
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# include "storage_backend_iscsi.h"
66
#endif
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#if WITH_STORAGE_SCSI
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# include "storage_backend_scsi.h"
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#endif
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#if WITH_STORAGE_MPATH
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# include "storage_backend_mpath.h"
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#endif
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#if WITH_STORAGE_DISK
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# include "storage_backend_disk.h"
75 76
#endif
#if WITH_STORAGE_DIR
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# include "storage_backend_fs.h"
78 79
#endif

80 81
#define VIR_FROM_THIS VIR_FROM_STORAGE

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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
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#if WITH_STORAGE_SCSI
    &virStorageBackendSCSI,
#endif
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#if WITH_STORAGE_MPATH
    &virStorageBackendMpath,
#endif
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#if WITH_STORAGE_DISK
    &virStorageBackendDisk,
#endif
    NULL
};
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static int track_allocation_progress = 0;

enum {
    TOOL_QEMU_IMG,
    TOOL_KVM_IMG,
    TOOL_QCOW_CREATE,
};

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#define READ_BLOCK_SIZE_DEFAULT  (1024 * 1024)
#define WRITE_BLOCK_SIZE_DEFAULT (4 * 1024)

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static int ATTRIBUTE_NONNULL (2)
virStorageBackendCopyToFD(virStorageVolDefPtr vol,
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                          virStorageVolDefPtr inputvol,
                          int fd,
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                          unsigned long long *total,
                          int is_dest_file)
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{
    int inputfd = -1;
    int amtread = -1;
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    int ret = 0;
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    unsigned long long remain;
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    size_t rbytes = READ_BLOCK_SIZE_DEFAULT;
    size_t wbytes = 0;
    int interval;
    char *zerobuf;
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    char *buf = NULL;
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    struct stat st;
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    if ((inputfd = open(inputvol->target.path, O_RDONLY)) < 0) {
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        ret = -errno;
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        virReportSystemError(errno,
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                             _("could not open input path '%s'"),
                             inputvol->target.path);
        goto cleanup;
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    }

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#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;
        virReportOOMError();
        goto cleanup;
    }
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    if (VIR_ALLOC_N(buf, rbytes) < 0) {
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        ret = -errno;
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        virReportOOMError();
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        goto cleanup;
    }

    remain = *total;

    while (amtread != 0) {
        int amtleft;

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        if (remain < rbytes)
            rbytes = remain;
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        if ((amtread = saferead(inputfd, buf, rbytes)) < 0) {
176
            ret = -errno;
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            virReportSystemError(errno,
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                                 _("failed reading from file '%s'"),
                                 inputvol->target.path);
            goto cleanup;
        }
        remain -= amtread;

        /* Loop over amt read in 512 byte increments, looking for sparse
         * blocks */
        amtleft = amtread;
        do {
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            interval = ((wbytes > amtleft) ? amtleft : wbytes);
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            int offset = amtread - amtleft;

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            if (is_dest_file && memcmp(buf+offset, zerobuf, interval) == 0) {
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                if (lseek(fd, interval, SEEK_CUR) < 0) {
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                    ret = -errno;
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                    virReportSystemError(errno,
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                                         _("cannot extend file '%s'"),
                                         vol->target.path);
                    goto cleanup;
                }
            } else if (safewrite(fd, buf+offset, interval) < 0) {
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                ret = -errno;
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                virReportSystemError(errno,
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                                     _("failed writing to file '%s'"),
                                     vol->target.path);
                goto cleanup;

            }
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        } while ((amtleft -= interval) > 0);
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    }

210
    if (VIR_CLOSE(inputfd) < 0) {
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        ret = -errno;
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        virReportSystemError(errno,
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                             _("cannot close file '%s'"),
                             inputvol->target.path);
        goto cleanup;
    }
    inputfd = -1;

    *total -= remain;

cleanup:
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    VIR_FORCE_CLOSE(inputfd);
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    VIR_FREE(zerobuf);
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    VIR_FREE(buf);

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    return ret;
}

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static int
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virStorageBackendCreateBlockFrom(virConnectPtr conn ATTRIBUTE_UNUSED,
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                                 virStoragePoolObjPtr pool ATTRIBUTE_UNUSED,
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                                 virStorageVolDefPtr vol,
                                 virStorageVolDefPtr inputvol,
                                 unsigned int flags ATTRIBUTE_UNUSED)
{
    int fd = -1;
    int ret = -1;
    unsigned long long remain;
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    struct stat st;
    gid_t gid;
    uid_t uid;
243 244

    if ((fd = open(vol->target.path, O_RDWR)) < 0) {
245
        virReportSystemError(errno,
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                             _("cannot create path '%s'"),
                             vol->target.path);
        goto cleanup;
    }

    remain = vol->allocation;

    if (inputvol) {
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        int res = virStorageBackendCopyToFD(vol, inputvol,
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                                            fd, &remain, 0);
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        if (res < 0)
            goto cleanup;
    }

260
    if (fstat(fd, &st) == -1) {
261
        virReportSystemError(errno, _("stat of '%s' failed"),
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                             vol->target.path);
        goto cleanup;
    }
    uid = (vol->target.perms.uid != st.st_uid) ? vol->target.perms.uid : -1;
    gid = (vol->target.perms.gid != st.st_gid) ? vol->target.perms.gid : -1;
    if (((uid != -1) || (gid != -1))
268
        && (fchown(fd, uid, gid) < 0)) {
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        virReportSystemError(errno,
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                             _("cannot chown '%s' to (%u, %u)"),
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                             vol->target.path, uid, gid);
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        goto cleanup;
    }
    if (fchmod(fd, vol->target.perms.mode) < 0) {
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        virReportSystemError(errno,
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                             _("cannot set mode of '%s' to %04o"),
                             vol->target.path, vol->target.perms.mode);
        goto cleanup;
    }
280
    if (VIR_CLOSE(fd) < 0) {
281
        virReportSystemError(errno,
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                             _("cannot close file '%s'"),
                             vol->target.path);
        goto cleanup;
    }
    fd = -1;

    ret = 0;
cleanup:
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    VIR_FORCE_CLOSE(fd);
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    return ret;
}

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static int
createRawFile(int fd, virStorageVolDefPtr vol,
              virStorageVolDefPtr inputvol)
{
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    int ret = 0;
    unsigned long long remain;
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    /* Seek to the final size, so the capacity is available upfront
     * for progress reporting */
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    if (ftruncate(fd, vol->capacity) < 0) {
305
        ret = -errno;
306
        virReportSystemError(errno,
307
                             _("cannot extend file '%s'"),
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                             vol->target.path);
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        goto cleanup;
    }

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    remain = vol->allocation;
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    if (inputvol) {
        ret = virStorageBackendCopyToFD(vol, inputvol, fd, &remain, 1);
316
        if (ret < 0) {
317
            goto cleanup;
318
        }
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    }

    if (remain) {
        if (track_allocation_progress) {

            while (remain) {
                /* Allocate in chunks of 512MiB: big-enough chunk
                 * size and takes approx. 9s on ext3. A progress
                 * update every 9s is a fair-enough trade-off
                 */
                unsigned long long bytes = 512 * 1024 * 1024;

                if (bytes > remain)
                    bytes = remain;
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                if (safezero(fd, 0, vol->allocation - remain, bytes) != 0) {
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                    ret = -errno;
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                    virReportSystemError(errno, _("cannot fill file '%s'"),
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                                         vol->target.path);
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                    goto cleanup;
                }
                remain -= bytes;
            }
        } else { /* No progress bars to be shown */
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            if (safezero(fd, 0, 0, remain) != 0) {
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                ret = -errno;
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                virReportSystemError(errno, _("cannot fill file '%s'"),
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                                     vol->target.path);
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                goto cleanup;
            }
        }
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    }

    if (fsync(fd) < 0) {
353
        ret = -errno;
354
        virReportSystemError(errno, _("cannot sync data to file '%s'"),
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                             vol->target.path);
356
        goto cleanup;
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    }

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cleanup:
    return ret;
}

int
virStorageBackendCreateRaw(virConnectPtr conn ATTRIBUTE_UNUSED,
                           virStoragePoolObjPtr pool,
                           virStorageVolDefPtr vol,
                           virStorageVolDefPtr inputvol,
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                           unsigned int flags)
369 370
{
    int ret = -1;
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    int fd = -1;
    uid_t uid;
    gid_t gid;
    int operation_flags;

    virCheckFlags(0, -1);
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    if (vol->target.encryption != NULL) {
        virStorageReportError(VIR_ERR_NO_SUPPORT,
                              "%s", _("storage pool does not support encrypted "
                                      "volumes"));
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        goto cleanup;
    }
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    uid = (vol->target.perms.uid == -1) ? getuid() : vol->target.perms.uid;
    gid = (vol->target.perms.gid == -1) ? getgid() : vol->target.perms.gid;
387
    operation_flags = VIR_FILE_OPEN_FORCE_PERMS;
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    if (pool->def->type == VIR_STORAGE_POOL_NETFS)
389
        operation_flags |= VIR_FILE_OPEN_AS_UID;
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    if ((fd = virFileOpenAs(vol->target.path,
                            O_RDWR | O_CREAT | O_EXCL,
                            vol->target.perms.mode, uid, gid,
                            operation_flags)) < 0) {
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        virReportSystemError(-fd,
                             _("cannot create path '%s'"),
                             vol->target.path);
        goto cleanup;
    }

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    if ((ret = createRawFile(fd, vol, inputvol)) < 0) {
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        virReportSystemError(-fd,
                             _("cannot create path '%s'"),
                             vol->target.path);
        ret = -1;
406
    }
407 408

cleanup:
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    VIR_FORCE_CLOSE(fd);
410 411 412
    return ret;
}

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static int
virStorageGenerateSecretUUID(virConnectPtr conn,
                             unsigned char *uuid)
{
    unsigned attempt;

    for (attempt = 0; attempt < 65536; attempt++) {
        virSecretPtr tmp;
        if (virUUIDGenerate(uuid) < 0) {
422 423
            virStorageReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                                  _("unable to generate uuid"));
424 425 426 427 428 429 430 431 432
            return -1;
        }
        tmp = conn->secretDriver->lookupByUUID(conn, uuid);
        if (tmp == NULL)
            return 0;

        virSecretFree(tmp);
    }

433 434
    virStorageReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                          _("too many conflicts when generating an uuid"));
435 436 437 438

    return -1;
}

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static int
virStorageGenerateQcowEncryption(virConnectPtr conn,
                                 virStorageVolDefPtr vol)
{
    virSecretDefPtr def = NULL;
    virBuffer buf = VIR_BUFFER_INITIALIZER;
    virStorageEncryptionPtr enc;
    virStorageEncryptionSecretPtr enc_secret = NULL;
    virSecretPtr secret = NULL;
448
    char *xml;
449 450 451
    unsigned char value[VIR_STORAGE_QCOW_PASSPHRASE_SIZE];
    int ret = -1;

452 453 454
    if (conn->secretDriver == NULL ||
        conn->secretDriver->lookupByUUID == NULL ||
        conn->secretDriver->defineXML == NULL ||
455
        conn->secretDriver->setValue == NULL) {
456
        virStorageReportError(VIR_ERR_NO_SUPPORT, "%s",
457 458 459 460 461 462
                              _("secret storage not supported"));
        goto cleanup;
    }

    enc = vol->target.encryption;
    if (enc->nsecrets != 0) {
463
        virStorageReportError(VIR_ERR_INTERNAL_ERROR, "%s",
464 465 466 467 468 469
                              _("secrets already defined"));
        goto cleanup;
    }

    if (VIR_ALLOC(enc_secret) < 0 || VIR_REALLOC_N(enc->secrets, 1) < 0 ||
        VIR_ALLOC(def) < 0) {
470
        virReportOOMError();
471 472 473 474 475
        goto cleanup;
    }

    def->ephemeral = 0;
    def->private = 0;
476
    if (virStorageGenerateSecretUUID(conn, def->uuid) < 0)
477
        goto cleanup;
478

479 480 481
    def->usage_type = VIR_SECRET_USAGE_TYPE_VOLUME;
    def->usage.volume = strdup(vol->target.path);
    if (def->usage.volume == NULL) {
482
        virReportOOMError();
483 484
        goto cleanup;
    }
485
    xml = virSecretDefFormat(def);
486 487 488 489 490 491 492 493 494 495 496 497
    virSecretDefFree(def);
    def = NULL;
    if (xml == NULL)
        goto cleanup;

    secret = conn->secretDriver->defineXML(conn, xml, 0);
    if (secret == NULL) {
        VIR_FREE(xml);
        goto cleanup;
    }
    VIR_FREE(xml);

498
    if (virStorageGenerateQcowPassphrase(value) < 0)
499 500 501 502 503 504
        goto cleanup;

    if (conn->secretDriver->setValue(secret, value, sizeof(value), 0) < 0)
        goto cleanup;

    enc_secret->type = VIR_STORAGE_ENCRYPTION_SECRET_TYPE_PASSPHRASE;
505
    memcpy(enc_secret->uuid, secret->uuid, VIR_UUID_BUFLEN);
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    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) {
515 516
        if (ret != 0 &&
            conn->secretDriver->undefine != NULL)
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            conn->secretDriver->undefine(secret);
        virSecretFree(secret);
    }
520
    virBufferFreeAndReset(&buf);
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    virSecretDefFree(def);
    VIR_FREE(enc_secret);
    return ret;
}

526 527 528 529 530
struct hookdata {
    virStorageVolDefPtr vol;
    bool skip;
};

531
static int virStorageBuildSetUIDHook(void *data) {
532 533 534 535 536
    struct hookdata *tmp = data;
    virStorageVolDefPtr vol = tmp->vol;

    if (tmp->skip)
        return 0;
537

538
    if ((vol->target.perms.gid != -1)
539
        && (setgid(vol->target.perms.gid) != 0)) {
540
        virReportSystemError(errno,
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                             _("Cannot set gid to %u before creating %s"),
                             vol->target.perms.gid, vol->target.path);
        return -1;
    }
545
    if ((vol->target.perms.uid != -1)
546
        && (setuid(vol->target.perms.uid) != 0)) {
547
        virReportSystemError(errno,
548 549 550 551 552 553 554
                             _("Cannot set uid to %u before creating %s"),
                             vol->target.perms.uid, vol->target.path);
        return -1;
    }
    return 0;
}

555
static int virStorageBackendCreateExecCommand(virStoragePoolObjPtr pool,
556
                                              virStorageVolDefPtr vol,
557
                                              virCommandPtr cmd) {
558 559 560 561
    struct stat st;
    gid_t gid;
    uid_t uid;
    int filecreated = 0;
562
    struct hookdata data = {vol, false};
563 564

    if ((pool->def->type == VIR_STORAGE_POOL_NETFS)
565 566 567 568 569
        && (((getuid() == 0)
             && (vol->target.perms.uid != -1)
             && (vol->target.perms.uid != 0))
            || ((vol->target.perms.gid != -1)
                && (vol->target.perms.gid != getgid())))) {
570 571 572 573

        virCommandSetPreExecHook(cmd, virStorageBuildSetUIDHook, &data);

        if (virCommandRun(cmd, NULL) == 0) {
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            /* command was successfully run, check if the file was created */
            if (stat(vol->target.path, &st) >=0)
                filecreated = 1;
        }
    }
579 580 581

    data.skip = true;

582
    if (!filecreated) {
583
        if (virCommandRun(cmd, NULL) < 0) {
584 585 586
            return -1;
        }
        if (stat(vol->target.path, &st) < 0) {
587
            virReportSystemError(errno,
588
                                 _("failed to create %s"), vol->target.path);
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            return -1;
        }
    }

    uid = (vol->target.perms.uid != st.st_uid) ? vol->target.perms.uid : -1;
    gid = (vol->target.perms.gid != st.st_gid) ? vol->target.perms.gid : -1;
    if (((uid != -1) || (gid != -1))
        && (chown(vol->target.path, uid, gid) < 0)) {
597
        virReportSystemError(errno,
598
                             _("cannot chown %s to (%u, %u)"),
599
                             vol->target.path, uid, gid);
600 601 602
        return -1;
    }
    if (chmod(vol->target.path, vol->target.perms.mode) < 0) {
603
        virReportSystemError(errno,
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                             _("cannot set mode of '%s' to %04o"),
                             vol->target.path, vol->target.perms.mode);
        return -1;
    }
    return 0;
}

611 612 613 614 615 616 617 618 619 620 621 622 623
enum {
    QEMU_IMG_BACKING_FORMAT_NONE = 0,
    QEMU_IMG_BACKING_FORMAT_FLAG,
    QEMU_IMG_BACKING_FORMAT_OPTIONS,
};

static int virStorageBackendQEMUImgBackingFormat(const char *qemuimg)
{
    char *help = NULL;
    char *start;
    char *end;
    char *tmp;
    int ret = -1;
624
    int exitstatus;
625
    virCommandPtr cmd = virCommandNewArgList(qemuimg, "-h", NULL);
626

627 628 629
    virCommandAddEnvString(cmd, "LC_ALL=C");
    virCommandSetOutputBuffer(cmd, &help);
    virCommandClearCaps(cmd);
630

631 632 633
    /* 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 */
634
    if (virCommandRun(cmd, &exitstatus) < 0)
635 636 637 638
        goto cleanup;

    start = strstr(help, " create ");
    end = strstr(start, "\n");
639 640
    if (((tmp = strstr(start, "-F fmt")) && tmp < end) ||
        ((tmp = strstr(start, "-F backing_fmt")) && tmp < end))
641 642 643 644 645 646 647
        ret = QEMU_IMG_BACKING_FORMAT_FLAG;
    else if ((tmp = strstr(start, "[-o options]")) && tmp < end)
        ret = QEMU_IMG_BACKING_FORMAT_OPTIONS;
    else
        ret = QEMU_IMG_BACKING_FORMAT_NONE;

cleanup:
648
    virCommandFree(cmd);
649 650 651 652 653
    VIR_FREE(help);
    return ret;
}


654 655
static int
virStorageBackendCreateQemuImg(virConnectPtr conn,
656
                               virStoragePoolObjPtr pool,
657
                               virStorageVolDefPtr vol,
658 659
                               virStorageVolDefPtr inputvol,
                               unsigned int flags ATTRIBUTE_UNUSED)
660
{
661
    int ret = -1;
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662
    char *size = NULL;
663
    char *create_tool;
664
    int imgformat = -1;
665 666
    virCommandPtr cmd = NULL;
    bool do_encryption = (vol->target.encryption != NULL);
667

668
    const char *type = virStorageFileFormatTypeToString(vol->target.format);
669
    const char *backingType = vol->backingStore.path ?
670
        virStorageFileFormatTypeToString(vol->backingStore.format) : NULL;
671 672 673 674 675 676

    const char *inputBackingPath = (inputvol ? inputvol->backingStore.path
                                             : NULL);
    const char *inputPath = inputvol ? inputvol->target.path : NULL;
    /* Treat input block devices as 'raw' format */
    const char *inputType = inputPath ?
677 678 679 680
        virStorageFileFormatTypeToString(inputvol->type == VIR_STORAGE_VOL_BLOCK ?
                                         VIR_STORAGE_FILE_RAW :
                                         inputvol->target.format) :
        NULL;
681 682

    if (type == NULL) {
683
        virStorageReportError(VIR_ERR_INTERNAL_ERROR,
684 685 686 687 688
                              _("unknown storage vol type %d"),
                              vol->target.format);
        return -1;
    }
    if (inputvol && inputType == NULL) {
689
        virStorageReportError(VIR_ERR_INTERNAL_ERROR,
690 691 692 693 694 695
                              _("unknown storage vol type %d"),
                              inputvol->target.format);
        return -1;
    }

    if (vol->backingStore.path) {
696 697
        int accessRetCode = -1;
        char *absolutePath = NULL;
698 699 700 701 702 703 704 705

        /* 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 &&
            (!inputBackingPath ||
             STRNEQ(inputBackingPath, vol->backingStore.path))) {
706
            virStorageReportError(VIR_ERR_INTERNAL_ERROR,
E
Eric Blake 已提交
707
                                  "%s", _("a different backing store cannot "
708 709 710 711 712
                                          "be specified."));
            return -1;
        }

        if (backingType == NULL) {
713
            virStorageReportError(VIR_ERR_INTERNAL_ERROR,
714 715 716 717
                                  _("unknown storage vol backing store type %d"),
                                  vol->backingStore.format);
            return -1;
        }
718 719 720 721 722 723 724 725 726 727 728 729 730 731

        /* Convert relative backing store paths to absolute paths for access
         * validation.
         */
        if ('/' != *(vol->backingStore.path) &&
            virAsprintf(&absolutePath, "%s/%s", pool->def->target.path,
                        vol->backingStore.path) < 0) {
            virReportOOMError();
            return -1;
        }
        accessRetCode = access(absolutePath ? absolutePath
                               : vol->backingStore.path, R_OK);
        VIR_FREE(absolutePath);
        if (accessRetCode != 0) {
732
            virReportSystemError(errno,
733 734 735 736 737 738
                                 _("inaccessible backing store volume %s"),
                                 vol->backingStore.path);
            return -1;
        }
    }

739
    if (do_encryption) {
740 741
        virStorageEncryptionPtr enc;

742 743
        if (vol->target.format != VIR_STORAGE_FILE_QCOW &&
            vol->target.format != VIR_STORAGE_FILE_QCOW2) {
744
            virStorageReportError(VIR_ERR_NO_SUPPORT,
745 746 747 748
                                  _("qcow volume encryption unsupported with "
                                    "volume format %s"), type);
            return -1;
        }
749 750 751
        enc = vol->target.encryption;
        if (enc->format != VIR_STORAGE_ENCRYPTION_FORMAT_QCOW &&
            enc->format != VIR_STORAGE_ENCRYPTION_FORMAT_DEFAULT) {
752
            virStorageReportError(VIR_ERR_NO_SUPPORT,
753 754 755 756
                                  _("unsupported volume encryption format %d"),
                                  vol->target.encryption->format);
            return -1;
        }
757
        if (enc->nsecrets > 1) {
758
            virStorageReportError(VIR_ERR_XML_ERROR, "%s",
759 760 761
                                  _("too many secrets for qcow encryption"));
            return -1;
        }
762 763 764 765 766
        if (enc->format == VIR_STORAGE_ENCRYPTION_FORMAT_DEFAULT ||
            enc->nsecrets == 0) {
            if (virStorageGenerateQcowEncryption(conn, vol) < 0)
                return -1;
        }
767 768
    }

769
    /* Size in KB */
770
    if (virAsprintf(&size, "%lluK", VIR_DIV_UP(vol->capacity, 1024)) < 0) {
E
Eric Blake 已提交
771 772 773
        virReportOOMError();
        goto cleanup;
    }
774 775 776 777 778 779 780

    /* 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) {
781
        virStorageReportError(VIR_ERR_INTERNAL_ERROR,
782
                              "%s", _("unable to find kvm-img or qemu-img"));
783 784 785
        return -1;
    }

786 787 788 789
    imgformat = virStorageBackendQEMUImgBackingFormat(create_tool);
    if (imgformat < 0)
        goto cleanup;

790 791
    cmd = virCommandNew(create_tool);

792
    if (inputvol) {
793 794 795 796
        virCommandAddArgList(cmd, "convert", "-f", inputType, "-O", type,
                             inputPath, vol->target.path, NULL);

        if (do_encryption) {
797
            if (imgformat == QEMU_IMG_BACKING_FORMAT_OPTIONS) {
798
                virCommandAddArgList(cmd, "-o", "encryption=on", NULL);
799
            } else {
800
                virCommandAddArg(cmd, "-e");
801 802 803
            }
        }

804
    } else if (vol->backingStore.path) {
805 806 807
        virCommandAddArgList(cmd, "create", "-f", type,
                             "-b", vol->backingStore.path, NULL);

808 809
        switch (imgformat) {
        case QEMU_IMG_BACKING_FORMAT_FLAG:
810 811 812 813 814
            virCommandAddArgList(cmd, "-F", backingType, vol->target.path,
                                 size, NULL);

            if (do_encryption)
                virCommandAddArg(cmd, "-e");
815 816 817
            break;

        case QEMU_IMG_BACKING_FORMAT_OPTIONS:
818 819 820 821 822
            virCommandAddArg(cmd, "-o");
            virCommandAddArgFormat(cmd, "backing_fmt=%s%s", backingType,
                                   do_encryption ? ",encryption=on" : "");
            virCommandAddArgList(cmd, vol->target.path, size, NULL);
            break;
823 824 825 826 827

        default:
            VIR_INFO("Unable to set backing store format for %s with %s",
                     vol->target.path, create_tool);

828 829 830 831
            virCommandAddArgList(cmd, vol->target.path, size, NULL);
            if (do_encryption)
                virCommandAddArg(cmd, "-e");
        }
832
    } else {
833 834 835 836
        virCommandAddArgList(cmd, "create", "-f", type,
                             vol->target.path, size, NULL);

        if (do_encryption) {
837
            if (imgformat == QEMU_IMG_BACKING_FORMAT_OPTIONS) {
838
                virCommandAddArgList(cmd, "-o", "encryption=on", NULL);
839
            } else {
840
                virCommandAddArg(cmd, "-e");
841 842
            }
        }
843
    }
844

845 846
    ret = virStorageBackendCreateExecCommand(pool, vol, cmd);
cleanup:
E
Eric Blake 已提交
847
    VIR_FREE(size);
848
    VIR_FREE(create_tool);
849
    virCommandFree(cmd);
850

851
    return ret;
852 853 854 855 856 857 858
}

/*
 * Xen removed the fully-functional qemu-img, and replaced it
 * with a partially functional qcow-create. Go figure ??!?
 */
static int
859
virStorageBackendCreateQcowCreate(virConnectPtr conn ATTRIBUTE_UNUSED,
860
                                  virStoragePoolObjPtr pool,
861
                                  virStorageVolDefPtr vol,
862 863
                                  virStorageVolDefPtr inputvol,
                                  unsigned int flags ATTRIBUTE_UNUSED)
864
{
865
    int ret;
E
Eric Blake 已提交
866
    char *size;
867
    virCommandPtr cmd;
868 869

    if (inputvol) {
870
        virStorageReportError(VIR_ERR_INTERNAL_ERROR, "%s",
871 872 873 874
                              _("cannot copy from volume with qcow-create"));
        return -1;
    }

875
    if (vol->target.format != VIR_STORAGE_FILE_QCOW2) {
876
        virStorageReportError(VIR_ERR_INTERNAL_ERROR,
877 878 879 880 881
                              _("unsupported storage vol type %d"),
                              vol->target.format);
        return -1;
    }
    if (vol->backingStore.path != NULL) {
882
        virStorageReportError(VIR_ERR_NO_SUPPORT, "%s",
883
                              _("copy-on-write image not supported with "
884
                                      "qcow-create"));
885 886
        return -1;
    }
887
    if (vol->target.encryption != NULL) {
888
        virStorageReportError(VIR_ERR_NO_SUPPORT,
889 890 891 892
                              "%s", _("encrypted volumes not supported with "
                                      "qcow-create"));
        return -1;
    }
893 894

    /* Size in MB - yes different units to qemu-img :-( */
895 896
    if (virAsprintf(&size, "%llu",
                    VIR_DIV_UP(vol->capacity, (1024 * 1024))) < 0) {
E
Eric Blake 已提交
897 898 899
        virReportOOMError();
        return -1;
    }
900

901
    cmd = virCommandNewArgList("qcow-create", size, vol->target.path, NULL);
902

903 904
    ret = virStorageBackendCreateExecCommand(pool, vol, cmd);
    virCommandFree(cmd);
E
Eric Blake 已提交
905
    VIR_FREE(size);
906

907
    return ret;
908 909
}

910
virStorageBackendBuildVolFrom
911
virStorageBackendFSImageToolTypeToFunc(int tool_type)
912 913 914 915 916 917 918 919
{
    switch (tool_type) {
    case TOOL_KVM_IMG:
    case TOOL_QEMU_IMG:
        return virStorageBackendCreateQemuImg;
    case TOOL_QCOW_CREATE:
        return virStorageBackendCreateQcowCreate;
    default:
920
        virStorageReportError(VIR_ERR_INTERNAL_ERROR,
921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949
                              _("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;
}

950
virStorageBackendBuildVolFrom
951
virStorageBackendGetBuildVolFromFunction(virStorageVolDefPtr vol,
952 953 954 955 956 957 958 959 960 961 962
                                         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 &&
963
         vol->target.format != VIR_STORAGE_FILE_RAW) ||
964
        (inputvol->type == VIR_STORAGE_VOL_FILE &&
965
         inputvol->target.format != VIR_STORAGE_FILE_RAW)) {
966

D
Daniel P. Berrange 已提交
967
        if ((tool_type = virStorageBackendFindFSImageTool(NULL)) < 0) {
968
            virStorageReportError(VIR_ERR_INTERNAL_ERROR,
969 970 971 972 973
                                  "%s", _("creation of non-raw file images is "
                                          "not supported without qemu-img."));
            return NULL;
        }

974
        return virStorageBackendFSImageToolTypeToFunc(tool_type);
975 976
    }

977 978 979 980
    if (vol->type == VIR_STORAGE_VOL_BLOCK)
        return virStorageBackendCreateBlockFrom;
    else
        return virStorageBackendCreateRaw;
981
}
982

983

984 985
virStorageBackendPtr
virStorageBackendForType(int type) {
986
    unsigned int i;
987
    for (i = 0; backends[i]; i++)
988 989 990
        if (backends[i]->type == type)
            return backends[i];

991
    virStorageReportError(VIR_ERR_INTERNAL_ERROR,
992 993 994 995 996
                          _("missing backend for pool type %d"), type);
    return NULL;
}


997 998 999
/*
 * Allows caller to silently ignore files with improper mode
 *
1000 1001
 * Returns -1 on error, -2 if file mode is unexpected or the
 * volume is a dangling symbolic link.
1002
 */
1003
int
1004
virStorageBackendVolOpenCheckMode(const char *path, unsigned int flags)
1005
{
1006 1007
    int fd, mode = 0;
    struct stat sb;
1008

1009
    if ((fd = open(path, O_RDONLY|O_NONBLOCK|O_NOCTTY)) < 0) {
1010 1011 1012 1013 1014 1015
        if ((errno == ENOENT || errno == ELOOP) &&
            lstat(path, &sb) == 0) {
            VIR_WARN("ignoring dangling symlink '%s'", path);
            return -2;
        }

1016
        virReportSystemError(errno,
1017
                             _("cannot open volume '%s'"),
1018
                             path);
1019 1020 1021
        return -1;
    }

1022 1023 1024 1025
    if (fstat(fd, &sb) < 0) {
        virReportSystemError(errno,
                             _("cannot stat file '%s'"),
                             path);
1026
        VIR_FORCE_CLOSE(fd);
1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037
        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;

    if (!(mode & flags)) {
1038
        VIR_FORCE_CLOSE(fd);
1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068

        if (mode & VIR_STORAGE_VOL_OPEN_ERROR) {
            virStorageReportError(VIR_ERR_INTERNAL_ERROR,
                                  _("unexpected storage mode for '%s'"), path);
            return -1;
        }

        return -2;
    }

    return fd;
}

int virStorageBackendVolOpen(const char *path)
{
    return virStorageBackendVolOpenCheckMode(path,
                                             VIR_STORAGE_VOL_OPEN_DEFAULT);
}

int
virStorageBackendUpdateVolTargetInfo(virStorageVolTargetPtr target,
                                     unsigned long long *allocation,
                                     unsigned long long *capacity)
{
    int ret, fd;

    if ((ret = virStorageBackendVolOpen(target->path)) < 0)
        return ret;

    fd = ret;
1069
    ret = virStorageBackendUpdateVolTargetInfoFD(target,
1070 1071 1072
                                                 fd,
                                                 allocation,
                                                 capacity);
1073

1074
    VIR_FORCE_CLOSE(fd);
1075 1076 1077 1078

    return ret;
}

1079
int
1080
virStorageBackendUpdateVolInfo(virStorageVolDefPtr vol,
1081 1082 1083 1084
                               int withCapacity)
{
    int ret;

1085
    if ((ret = virStorageBackendUpdateVolTargetInfo(&vol->target,
1086 1087 1088 1089 1090
                                                    &vol->allocation,
                                                    withCapacity ? &vol->capacity : NULL)) < 0)
        return ret;

    if (vol->backingStore.path &&
1091
        (ret = virStorageBackendUpdateVolTargetInfo(&vol->backingStore,
1092 1093 1094 1095 1096 1097
                                                    NULL, NULL)) < 0)
        return ret;

    return 0;
}

1098 1099 1100 1101
/*
 * virStorageBackendUpdateVolTargetInfoFD:
 * @conn: connection to report errors on
 * @target: target definition ptr of volume to update
1102
 * @fd: fd of storage volume to update, via virStorageBackendOpenVol*
1103 1104 1105
 * @allocation: If not NULL, updated allocation information will be stored
 * @capacity: If not NULL, updated capacity info will be stored
 *
1106
 * Returns 0 for success, -1 on a legitimate error condition.
1107
 */
1108
int
1109
virStorageBackendUpdateVolTargetInfoFD(virStorageVolTargetPtr target,
1110 1111 1112
                                       int fd,
                                       unsigned long long *allocation,
                                       unsigned long long *capacity)
1113 1114 1115 1116 1117 1118 1119
{
    struct stat sb;
#if HAVE_SELINUX
    security_context_t filecon = NULL;
#endif

    if (fstat(fd, &sb) < 0) {
1120
        virReportSystemError(errno,
1121
                             _("cannot stat file '%s'"),
1122
                             target->path);
1123 1124 1125
        return -1;
    }

1126 1127
    if (allocation) {
        if (S_ISREG(sb.st_mode)) {
1128
#ifndef WIN32
1129
            *allocation = (unsigned long long)sb.st_blocks *
1130
                          (unsigned long long)DEV_BSIZE;
D
Daniel P. Berrange 已提交
1131
#else
1132
            *allocation = sb.st_size;
D
Daniel P. Berrange 已提交
1133
#endif
1134 1135 1136 1137 1138 1139 1140
            /* Regular files may be sparse, so logical size (capacity) is not same
             * as actual allocation above
             */
            if (capacity)
                *capacity = sb.st_size;
        } else {
            off_t end;
E
Eric Blake 已提交
1141
            /* XXX this is POSIX compliant, but doesn't work for CHAR files,
1142 1143 1144 1145 1146 1147
             * 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) {
1148
                virReportSystemError(errno,
1149 1150 1151 1152 1153 1154 1155
                                     _("cannot seek to end of file '%s'"),
                                     target->path);
                return -1;
            }
            *allocation = end;
            if (capacity)
                *capacity = end;
1156 1157 1158
        }
    }

1159 1160 1161
    target->perms.mode = sb.st_mode & S_IRWXUGO;
    target->perms.uid = sb.st_uid;
    target->perms.gid = sb.st_gid;
1162

1163
    VIR_FREE(target->perms.label);
1164 1165

#if HAVE_SELINUX
1166
    /* XXX: make this a security driver call */
1167
    if (fgetfilecon(fd, &filecon) == -1) {
1168
        if (errno != ENODATA && errno != ENOTSUP) {
1169
            virReportSystemError(errno,
1170
                                 _("cannot get file context of '%s'"),
1171
                                 target->path);
1172 1173
            return -1;
        } else {
1174
            target->perms.label = NULL;
1175 1176
        }
    } else {
1177
        target->perms.label = strdup(filecon);
1178
        freecon(filecon);
1179
        if (target->perms.label == NULL) {
1180
            virReportOOMError();
1181 1182
            return -1;
        }
1183 1184
    }
#else
1185
    target->perms.label = NULL;
1186 1187 1188 1189 1190
#endif

    return 0;
}

D
Dave Allan 已提交
1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225

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 },
};


int
1226 1227
virStorageBackendDetectBlockVolFormatFD(virStorageVolTargetPtr target,
                                        int fd)
D
Dave Allan 已提交
1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238
{
    int 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) {
1239
        virReportSystemError(errno,
D
Dave Allan 已提交
1240 1241 1242 1243 1244 1245
                             _("cannot seek to beginning of file '%s'"),
                             target->path);
        return -1;
    }
    bytes = saferead(fd, buffer, sizeof(buffer));
    if (bytes < 0) {
1246
        virReportSystemError(errno,
D
Dave Allan 已提交
1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265
                             _("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;
}


1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279
/*
 * 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.
 */
char *
1280
virStorageBackendStablePath(virStoragePoolObjPtr pool,
1281
                            const char *devpath)
1282 1283 1284
{
    DIR *dh;
    struct dirent *dent;
1285
    char *stablepath;
1286
    int opentries = 0;
1287 1288 1289 1290 1291

    /* 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/"))
1292
        goto ret_strdup;
1293

1294 1295 1296 1297 1298 1299
    /* Skip whole thing for a pool which isn't in /dev
     * so we don't mess will filesystem/dir based pools
     */
    if (!STRPREFIX(pool->def->target.path, "/dev"))
        goto ret_strdup;

1300 1301 1302
    /* 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.
1303
     */
1304
 reopen:
1305
    if ((dh = opendir(pool->def->target.path)) == NULL) {
1306 1307 1308 1309 1310
        opentries++;
        if (errno == ENOENT && opentries < 50) {
            usleep(100 * 1000);
            goto reopen;
        }
1311
        virReportSystemError(errno,
1312 1313
                             _("cannot read dir '%s'"),
                             pool->def->target.path);
1314 1315 1316
        return NULL;
    }

1317 1318 1319 1320 1321
    /* 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
     */
1322 1323 1324 1325
    while ((dent = readdir(dh)) != NULL) {
        if (dent->d_name[0] == '.')
            continue;

1326 1327 1328
        if (virAsprintf(&stablepath, "%s/%s",
                        pool->def->target.path,
                        dent->d_name) == -1) {
1329
            virReportOOMError();
1330 1331 1332 1333 1334 1335 1336 1337 1338
            closedir(dh);
            return NULL;
        }

        if (virFileLinkPointsTo(stablepath, devpath)) {
            closedir(dh);
            return stablepath;
        }

1339
        VIR_FREE(stablepath);
1340 1341 1342 1343
    }

    closedir(dh);

1344
 ret_strdup:
1345 1346 1347
    /* Couldn't find any matching stable link so give back
     * the original non-stable dev path
     */
1348 1349 1350 1351

    stablepath = strdup(devpath);

    if (stablepath == NULL)
1352
        virReportOOMError();
1353 1354

    return stablepath;
1355 1356
}

D
Daniel P. Berrange 已提交
1357

1358
#ifndef WIN32
1359 1360 1361 1362
/*
 * Run an external program.
 *
 * Read its output and apply a series of regexes to each line
R
Richard W.M. Jones 已提交
1363
 * When the entire set of regexes has matched consecutively
1364 1365 1366
 * then run a callback passing in all the matches
 */
int
1367
virStorageBackendRunProgRegex(virStoragePoolObjPtr pool,
1368
                              const char *const*prog,
1369 1370 1371 1372
                              int nregex,
                              const char **regex,
                              int *nvars,
                              virStorageBackendListVolRegexFunc func,
1373
                              void *data)
1374
{
1375
    int fd = -1, err, ret = -1;
1376 1377 1378 1379 1380 1381 1382
    FILE *list = NULL;
    regex_t *reg;
    regmatch_t *vars = NULL;
    char line[1024];
    int maxReg = 0, i, j;
    int totgroups = 0, ngroup = 0, maxvars = 0;
    char **groups;
1383
    virCommandPtr cmd = NULL;
1384 1385

    /* Compile all regular expressions */
1386
    if (VIR_ALLOC_N(reg, nregex) < 0) {
1387
        virReportOOMError();
1388 1389 1390 1391 1392 1393 1394 1395
        return -1;
    }

    for (i = 0 ; i < nregex ; i++) {
        err = regcomp(&reg[i], regex[i], REG_EXTENDED);
        if (err != 0) {
            char error[100];
            regerror(err, &reg[i], error, sizeof(error));
1396
            virStorageReportError(VIR_ERR_INTERNAL_ERROR,
1397 1398 1399
                                  _("Failed to compile regex %s"), error);
            for (j = 0 ; j <= i ; j++)
                regfree(&reg[j]);
1400
            VIR_FREE(reg);
1401 1402 1403 1404 1405 1406 1407 1408 1409 1410
            return -1;
        }

        totgroups += nvars[i];
        if (nvars[i] > maxvars)
            maxvars = nvars[i];

    }

    /* Storage for matched variables */
1411
    if (VIR_ALLOC_N(groups, totgroups) < 0) {
1412
        virReportOOMError();
1413 1414
        goto cleanup;
    }
1415
    if (VIR_ALLOC_N(vars, maxvars+1) < 0) {
1416
        virReportOOMError();
1417 1418 1419
        goto cleanup;
    }

1420 1421 1422
    cmd = virCommandNewArgs(prog);
    virCommandSetOutputFD(cmd, &fd);
    if (virCommandRunAsync(cmd, NULL) < 0) {
1423 1424 1425
        goto cleanup;
    }

1426
    if ((list = VIR_FDOPEN(fd, "r")) == NULL) {
1427
        virStorageReportError(VIR_ERR_INTERNAL_ERROR,
J
Jim Meyering 已提交
1428
                              "%s", _("cannot read fd"));
1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450
        goto cleanup;
    }

    while (fgets(line, sizeof(line), list) != NULL) {
        /* Strip trailing newline */
        int len = strlen(line);
        if (len && line[len-1] == '\n')
            line[len-1] = '\0';

        for (i = 0 ; i <= maxReg && i < nregex ; i++) {
            if (regexec(&reg[i], line, nvars[i]+1, vars, 0) == 0) {
                maxReg++;

                if (i == 0)
                    ngroup = 0;

                /* NULL terminate each captured group in the line */
                for (j = 0 ; j < nvars[i] ; j++) {
                    /* NB vars[0] is the full pattern, so we offset j by 1 */
                    line[vars[j+1].rm_eo] = '\0';
                    if ((groups[ngroup++] =
                         strdup(line + vars[j+1].rm_so)) == NULL) {
1451
                        virReportOOMError();
1452 1453 1454 1455 1456 1457
                        goto cleanup;
                    }
                }

                /* We're matching on the last regex, so callback time */
                if (i == (nregex-1)) {
1458
                    if (((*func)(pool, groups, data)) < 0)
1459 1460 1461
                        goto cleanup;

                    /* Release matches & restart to matching the first regex */
1462
                    for (j = 0 ; j < totgroups ; j++)
1463
                        VIR_FREE(groups[j]);
1464 1465 1466 1467 1468 1469 1470
                    maxReg = 0;
                    ngroup = 0;
                }
            }
        }
    }

1471
    ret = virCommandWait(cmd, NULL);
1472
cleanup:
1473 1474
    if (groups) {
        for (j = 0 ; j < totgroups ; j++)
1475 1476
            VIR_FREE(groups[j]);
        VIR_FREE(groups);
1477
    }
1478
    VIR_FREE(vars);
1479 1480 1481 1482

    for (i = 0 ; i < nregex ; i++)
        regfree(&reg[i]);

1483
    VIR_FREE(reg);
1484
    virCommandFree(cmd);
1485

1486 1487
    VIR_FORCE_FCLOSE(list);
    VIR_FORCE_CLOSE(fd);
1488

1489
    return ret;
1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503
}

/*
 * Run an external program and read from its standard output
 * a stream of tokens from IN_STREAM, applying FUNC to
 * each successive sequence of N_COLUMNS tokens.
 * If FUNC returns < 0, stop processing input and return -1.
 * Return -1 if N_COLUMNS == 0.
 * Return -1 upon memory allocation error.
 * If the number of input tokens is not a multiple of N_COLUMNS,
 * then the final FUNC call will specify a number smaller than N_COLUMNS.
 * If there are no input tokens (empty input), call FUNC with N_COLUMNS == 0.
 */
int
1504
virStorageBackendRunProgNul(virStoragePoolObjPtr pool,
1505 1506 1507 1508 1509 1510
                            const char **prog,
                            size_t n_columns,
                            virStorageBackendListVolNulFunc func,
                            void *data)
{
    size_t n_tok = 0;
1511
    int fd = -1;
1512 1513
    FILE *fp = NULL;
    char **v;
1514
    int ret = -1;
1515
    int i;
1516
    virCommandPtr cmd = NULL;
1517 1518 1519 1520

    if (n_columns == 0)
        return -1;

1521
    if (VIR_ALLOC_N(v, n_columns) < 0) {
1522
        virReportOOMError();
1523 1524 1525 1526 1527
        return -1;
    }
    for (i = 0; i < n_columns; i++)
        v[i] = NULL;

1528 1529 1530
    cmd = virCommandNewArgs(prog);
    virCommandSetOutputFD(cmd, &fd);
    if (virCommandRunAsync(cmd, NULL) < 0) {
1531 1532 1533
        goto cleanup;
    }

1534
    if ((fp = VIR_FDOPEN(fd, "r")) == NULL) {
1535
        virStorageReportError(VIR_ERR_INTERNAL_ERROR,
1536
                              "%s", _("cannot open file using fd"));
1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549
        goto cleanup;
    }

    while (1) {
        char *buf = NULL;
        size_t buf_len = 0;
        /* Be careful: even when it returns -1,
           this use of getdelim allocates memory.  */
        ssize_t tok_len = getdelim (&buf, &buf_len, 0, fp);
        v[n_tok] = buf;
        if (tok_len < 0) {
            /* Maybe EOF, maybe an error.
               If n_tok > 0, then we know it's an error.  */
1550
            if (n_tok && func (pool, n_tok, v, data) < 0)
1551 1552 1553 1554 1555
                goto cleanup;
            break;
        }
        ++n_tok;
        if (n_tok == n_columns) {
1556
            if (func (pool, n_tok, v, data) < 0)
1557 1558 1559
                goto cleanup;
            n_tok = 0;
            for (i = 0; i < n_columns; i++) {
1560
                VIR_FREE(v[i]);
1561 1562 1563 1564
            }
        }
    }

1565
    if (feof (fp) < 0) {
1566
        virReportSystemError(errno,
1567
                             _("read error on pipe to '%s'"), prog[0]);
1568 1569
        goto cleanup;
    }
1570

1571
    ret = virCommandWait(cmd, NULL);
1572 1573
 cleanup:
    for (i = 0; i < n_columns; i++)
1574 1575
        VIR_FREE(v[i]);
    VIR_FREE(v);
1576
    virCommandFree(cmd);
1577

1578 1579
    VIR_FORCE_FCLOSE(fp);
    VIR_FORCE_CLOSE(fd);
1580

1581
    return ret;
1582
}
D
Daniel P. Berrange 已提交
1583

1584
#else /* WIN32 */
D
Daniel P. Berrange 已提交
1585 1586 1587 1588 1589 1590 1591 1592 1593

int
virStorageBackendRunProgRegex(virConnectPtr conn,
                              virStoragePoolObjPtr pool ATTRIBUTE_UNUSED,
                              const char *const*prog ATTRIBUTE_UNUSED,
                              int nregex ATTRIBUTE_UNUSED,
                              const char **regex ATTRIBUTE_UNUSED,
                              int *nvars ATTRIBUTE_UNUSED,
                              virStorageBackendListVolRegexFunc func ATTRIBUTE_UNUSED,
1594
                              void *data ATTRIBUTE_UNUSED)
D
Daniel P. Berrange 已提交
1595
{
1596 1597
    virStorageReportError(VIR_ERR_INTERNAL_ERROR,
                          _("%s not implemented on Win32"), __FUNCTION__);
D
Daniel P. Berrange 已提交
1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608
    return -1;
}

int
virStorageBackendRunProgNul(virConnectPtr conn,
                            virStoragePoolObjPtr pool ATTRIBUTE_UNUSED,
                            const char **prog ATTRIBUTE_UNUSED,
                            size_t n_columns ATTRIBUTE_UNUSED,
                            virStorageBackendListVolNulFunc func ATTRIBUTE_UNUSED,
                            void *data ATTRIBUTE_UNUSED)
{
1609
    virStorageReportError(VIR_ERR_INTERNAL_ERROR, _("%s not implemented on Win32"), __FUNCTION__);
D
Daniel P. Berrange 已提交
1610 1611
    return -1;
}
1612
#endif /* WIN32 */