lxc_controller.c 55.2 KB
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/*
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 * Copyright (C) 2010-2011 Red Hat, Inc.
 * Copyright IBM Corp. 2008
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 *
 * lxc_controller.c: linux container process controller
 *
 * Authors:
 *  David L. Leskovec <dlesko at linux.vnet.ibm.com>
 *
 * 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
 */

#include <config.h>

#include <sys/epoll.h>
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#include <sys/wait.h>
#include <sys/socket.h>
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#include <sys/types.h>
#include <sys/un.h>
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#include <sys/utsname.h>
#include <sys/personality.h>
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#include <unistd.h>
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#include <paths.h>
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#include <errno.h>
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#include <fcntl.h>
#include <signal.h>
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#include <getopt.h>
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#include <sys/mount.h>
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#include <locale.h>
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#include <linux/loop.h>
#include <dirent.h>
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#include <grp.h>
#include <sys/stat.h>
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#include <time.h>
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#if HAVE_CAPNG
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# include <cap-ng.h>
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#endif

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#if HAVE_NUMACTL
# define NUMA_VERSION1_COMPATIBILITY 1
# include <numa.h>
#endif

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#include "virterror_internal.h"
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#include "logging.h"
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#include "util.h"

#include "lxc_conf.h"
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#include "lxc_container.h"
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#include "virnetdev.h"
#include "virnetdevveth.h"
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#include "memory.h"
#include "util.h"
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#include "virfile.h"
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#include "virpidfile.h"
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#include "command.h"
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#include "processinfo.h"
#include "nodeinfo.h"
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#include "virrandom.h"
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#define VIR_FROM_THIS VIR_FROM_LXC

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struct cgroup_device_policy {
    char type;
    int major;
    int minor;
};

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typedef struct _virLXCController virLXCController;
typedef virLXCController *virLXCControllerPtr;
struct _virLXCController {
    char *name;
    virDomainDefPtr def;
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    size_t nveths;
    char **veths;
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};

static void virLXCControllerFree(virLXCControllerPtr ctrl);

static virLXCControllerPtr virLXCControllerNew(const char *name)
{
    virLXCControllerPtr ctrl = NULL;
    virCapsPtr caps = NULL;
    char *configFile = NULL;

    if (VIR_ALLOC(ctrl) < 0)
        goto no_memory;

    if (!(ctrl->name = strdup(name)))
        goto no_memory;

    if ((caps = lxcCapsInit(NULL)) == NULL)
        goto error;

    if ((configFile = virDomainConfigFile(LXC_STATE_DIR,
                                          ctrl->name)) == NULL)
        goto error;

    if ((ctrl->def = virDomainDefParseFile(caps,
                                           configFile,
                                           1 << VIR_DOMAIN_VIRT_LXC,
                                           0)) == NULL)
        goto error;

cleanup:
    VIR_FREE(configFile);
    virCapabilitiesFree(caps);
    return ctrl;

no_memory:
    virReportOOMError();
error:
    virLXCControllerFree(ctrl);
    ctrl = NULL;
    goto cleanup;
}

static void virLXCControllerFree(virLXCControllerPtr ctrl)
{
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    size_t i;

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    if (!ctrl)
        return;

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    for (i = 0 ; i < ctrl->nveths ; i++)
        VIR_FREE(ctrl->veths[i]);
    VIR_FREE(ctrl->veths);

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    virDomainDefFree(ctrl->def);
    VIR_FREE(ctrl->name);

    VIR_FREE(ctrl);
}

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static int virLXCControllerValidateNICs(virLXCControllerPtr ctrl)
{
    if (ctrl->def->nnets != ctrl->nveths) {
        lxcError(VIR_ERR_INTERNAL_ERROR,
                 _("expecting %d veths, but got %zu"),
                 ctrl->def->nnets, ctrl->nveths);
        return -1;
    }

    return 0;
}


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static int lxcGetLoopFD(char **dev_name)
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{
    int fd = -1;
    DIR *dh = NULL;
    struct dirent *de;
    char *looppath;
    struct loop_info64 lo;

    VIR_DEBUG("Looking for loop devices in /dev");

    if (!(dh = opendir("/dev"))) {
        virReportSystemError(errno, "%s",
                             _("Unable to read /dev"));
        goto cleanup;
    }

    while ((de = readdir(dh)) != NULL) {
        if (!STRPREFIX(de->d_name, "loop"))
            continue;

        if (virAsprintf(&looppath, "/dev/%s", de->d_name) < 0) {
            virReportOOMError();
            goto cleanup;
        }

        VIR_DEBUG("Checking up on device %s", looppath);
        if ((fd = open(looppath, O_RDWR)) < 0) {
            virReportSystemError(errno,
                                 _("Unable to open %s"), looppath);
            goto cleanup;
        }

        if (ioctl(fd, LOOP_GET_STATUS64, &lo) < 0) {
            /* Got a free device, return the fd */
            if (errno == ENXIO)
                goto cleanup;

            VIR_FORCE_CLOSE(fd);
            virReportSystemError(errno,
                                 _("Unable to get loop status on %s"),
                                 looppath);
            goto cleanup;
        }

        /* Oh well, try the next device */
        VIR_FORCE_CLOSE(fd);
        VIR_FREE(looppath);
    }

    lxcError(VIR_ERR_INTERNAL_ERROR, "%s",
             _("Unable to find a free loop device in /dev"));

cleanup:
    if (fd != -1) {
        VIR_DEBUG("Got free loop device %s %d", looppath, fd);
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        *dev_name = looppath;
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    } else {
        VIR_DEBUG("No free loop devices available");
        VIR_FREE(looppath);
    }
    if (dh)
        closedir(dh);
    return fd;
}

static int lxcSetupLoopDevice(virDomainFSDefPtr fs)
{
    int lofd = -1;
    int fsfd = -1;
    struct loop_info64 lo;
    char *loname = NULL;
    int ret = -1;

    if ((lofd = lxcGetLoopFD(&loname)) < 0)
        return -1;

    memset(&lo, 0, sizeof(lo));
    lo.lo_flags = LO_FLAGS_AUTOCLEAR;

    if ((fsfd = open(fs->src, O_RDWR)) < 0) {
        virReportSystemError(errno,
                             _("Unable to open %s"), fs->src);
        goto cleanup;
    }

    if (ioctl(lofd, LOOP_SET_FD, fsfd) < 0) {
        virReportSystemError(errno,
                             _("Unable to attach %s to loop device"),
                             fs->src);
        goto cleanup;
    }

    if (ioctl(lofd, LOOP_SET_STATUS64, &lo) < 0) {
        virReportSystemError(errno, "%s",
                             _("Unable to mark loop device as autoclear"));

        if (ioctl(lofd, LOOP_CLR_FD, 0) < 0)
            VIR_WARN("Unable to detach %s from loop device", fs->src);
        goto cleanup;
    }

    VIR_DEBUG("Attached loop device  %s %d to %s", fs->src, lofd, loname);
    /*
     * We now change it into a block device type, so that
     * the rest of container setup 'just works'
     */
    fs->type = VIR_DOMAIN_FS_TYPE_BLOCK;
    VIR_FREE(fs->src);
    fs->src = loname;
    loname = NULL;

    ret = 0;

cleanup:
    VIR_FREE(loname);
    VIR_FORCE_CLOSE(fsfd);
    if (ret == -1)
        VIR_FORCE_CLOSE(lofd);
    return lofd;
}


static int lxcSetupLoopDevices(virDomainDefPtr def, size_t *nloopDevs, int **loopDevs)
{
    size_t i;
    int ret = -1;

    for (i = 0 ; i < def->nfss ; i++) {
        int fd;

        if (def->fss[i]->type != VIR_DOMAIN_FS_TYPE_FILE)
            continue;

        fd = lxcSetupLoopDevice(def->fss[i]);
        if (fd < 0)
            goto cleanup;

        VIR_DEBUG("Saving loop fd %d", fd);
        if (VIR_REALLOC_N(*loopDevs, *nloopDevs+1) < 0) {
            VIR_FORCE_CLOSE(fd);
            virReportOOMError();
            goto cleanup;
        }
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        (*loopDevs)[(*nloopDevs)++] = fd;
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    }

    VIR_DEBUG("Setup all loop devices");
    ret = 0;

cleanup:
    return ret;
}

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#if HAVE_NUMACTL
static int lxcSetContainerNUMAPolicy(virDomainDefPtr def)
{
    nodemask_t mask;
    int mode = -1;
    int node = -1;
    int ret = -1;
    int i = 0;
    int maxnode = 0;
    bool warned = false;

    if (!def->numatune.memory.nodemask)
        return 0;

    VIR_DEBUG("Setting NUMA memory policy");

    if (numa_available() < 0) {
        lxcError(VIR_ERR_CONFIG_UNSUPPORTED,
                 "%s", _("Host kernel is not aware of NUMA."));
        return -1;
    }

    maxnode = numa_max_node() + 1;

    /* Convert nodemask to NUMA bitmask. */
    nodemask_zero(&mask);
    for (i = 0; i < VIR_DOMAIN_CPUMASK_LEN; i++) {
        if (def->numatune.memory.nodemask[i]) {
            if (i > NUMA_NUM_NODES) {
                lxcError(VIR_ERR_CONFIG_UNSUPPORTED,
                         _("Host cannot support NUMA node %d"), i);
                return -1;
            }
            if (i > maxnode && !warned) {
                VIR_WARN("nodeset is out of range, there is only %d NUMA "
                         "nodes on host", maxnode);
                warned = true;
            }
            nodemask_set(&mask, i);
        }
    }

    mode = def->numatune.memory.mode;

    if (mode == VIR_DOMAIN_NUMATUNE_MEM_STRICT) {
        numa_set_bind_policy(1);
        numa_set_membind(&mask);
        numa_set_bind_policy(0);
    } else if (mode == VIR_DOMAIN_NUMATUNE_MEM_PREFERRED) {
        int nnodes = 0;
        for (i = 0; i < NUMA_NUM_NODES; i++) {
            if (nodemask_isset(&mask, i)) {
                node = i;
                nnodes++;
            }
        }

        if (nnodes != 1) {
            lxcError(VIR_ERR_CONFIG_UNSUPPORTED,
                     "%s", _("NUMA memory tuning in 'preferred' mode "
                             "only supports single node"));
            goto cleanup;
        }

        numa_set_bind_policy(0);
        numa_set_preferred(node);
    } else if (mode == VIR_DOMAIN_NUMATUNE_MEM_INTERLEAVE) {
        numa_set_interleave_mask(&mask);
    } else {
        lxcError(VIR_ERR_CONFIG_UNSUPPORTED,
                 _("Unable to set NUMA policy %s"),
                 virDomainNumatuneMemModeTypeToString(mode));
        goto cleanup;
    }

    ret = 0;

cleanup:
    return ret;
}
#else
static int lxcSetContainerNUMAPolicy(virDomainDefPtr def)
{
    if (def->numatune.memory.nodemask) {
        lxcError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
                 _("NUMA policy is not available on this platform"));
        return -1;
    }

    return 0;
}
#endif

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/*
 * To be run while still single threaded
 */
static int lxcSetContainerCpuAffinity(virDomainDefPtr def)
{
    int i, hostcpus, maxcpu = CPU_SETSIZE;
    virNodeInfo nodeinfo;
    unsigned char *cpumap;
    int cpumaplen;

    VIR_DEBUG("Setting CPU affinity");

    if (nodeGetInfo(NULL, &nodeinfo) < 0)
        return -1;

    /* setaffinity fails if you set bits for CPUs which
     * aren't present, so we have to limit ourselves */
    hostcpus = VIR_NODEINFO_MAXCPUS(nodeinfo);
    if (maxcpu > hostcpus)
        maxcpu = hostcpus;

    cpumaplen = VIR_CPU_MAPLEN(maxcpu);
    if (VIR_ALLOC_N(cpumap, cpumaplen) < 0) {
        virReportOOMError();
        return -1;
    }

    if (def->cpumask) {
        /* XXX why don't we keep 'cpumask' in the libvirt cpumap
         * format to start with ?!?! */
        for (i = 0 ; i < maxcpu && i < def->cpumasklen ; i++)
            if (def->cpumask[i])
                VIR_USE_CPU(cpumap, i);
    } else {
        /* You may think this is redundant, but we can't assume libvirtd
         * itself is running on all pCPUs, so we need to explicitly set
         * the spawned LXC instance to all pCPUs if no map is given in
         * its config file */
        for (i = 0 ; i < maxcpu ; i++)
            VIR_USE_CPU(cpumap, i);
    }

    /* We are pressuming we are running between fork/exec of LXC
     * so use '0' to indicate our own process ID. No threads are
     * running at this point
     */
    if (virProcessInfoSetAffinity(0, /* Self */
                                  cpumap, cpumaplen, maxcpu) < 0) {
        VIR_FREE(cpumap);
        return -1;
    }
    VIR_FREE(cpumap);

    return 0;
}


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static int lxcSetContainerCpuTune(virCgroupPtr cgroup, virDomainDefPtr def)
{
    int ret = -1;
    if (def->cputune.shares != 0) {
        int rc = virCgroupSetCpuShares(cgroup, def->cputune.shares);
        if (rc != 0) {
            virReportSystemError(-rc,
                                 _("Unable to set io cpu shares for domain %s"),
                                 def->name);
            goto cleanup;
        }
    }
    if (def->cputune.quota != 0) {
        int rc = virCgroupSetCpuCfsQuota(cgroup, def->cputune.quota);
        if (rc != 0) {
            virReportSystemError(-rc,
                                 _("Unable to set io cpu quota for domain %s"),
                                 def->name);
            goto cleanup;
        }
    }
    if (def->cputune.period != 0) {
        int rc = virCgroupSetCpuCfsPeriod(cgroup, def->cputune.period);
        if (rc != 0) {
            virReportSystemError(-rc,
                                 _("Unable to set io cpu period for domain %s"),
                                 def->name);
            goto cleanup;
        }
    }
    ret = 0;
cleanup:
    return ret;
}


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static int lxcSetContainerBlkioTune(virCgroupPtr cgroup, virDomainDefPtr def)
{
    int ret = -1;

    if (def->blkio.weight) {
        int rc = virCgroupSetBlkioWeight(cgroup, def->blkio.weight);
        if (rc != 0) {
            virReportSystemError(-rc,
                                 _("Unable to set Blkio weight for domain %s"),
                                 def->name);
            goto cleanup;
        }
    }

    ret = 0;
cleanup:
    return ret;
}


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static int lxcSetContainerMemTune(virCgroupPtr cgroup, virDomainDefPtr def)
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{
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    int ret = -1;
    int rc;
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529
    rc = virCgroupSetMemory(cgroup, def->mem.max_balloon);
530
    if (rc != 0) {
531
        virReportSystemError(-rc,
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                             _("Unable to set memory limit for domain %s"),
                             def->name);
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        goto cleanup;
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    }
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537
    if (def->mem.hard_limit) {
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        rc = virCgroupSetMemoryHardLimit(cgroup, def->mem.hard_limit);
        if (rc != 0) {
            virReportSystemError(-rc,
                                 _("Unable to set memory hard limit for domain %s"),
                                 def->name);
            goto cleanup;
        }
    }

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    if (def->mem.soft_limit) {
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        rc = virCgroupSetMemorySoftLimit(cgroup, def->mem.soft_limit);
        if (rc != 0) {
            virReportSystemError(-rc,
                                 _("Unable to set memory soft limit for domain %s"),
                                 def->name);
            goto cleanup;
        }
    }

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    if (def->mem.swap_hard_limit) {
558
        rc = virCgroupSetMemSwapHardLimit(cgroup, def->mem.swap_hard_limit);
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        if (rc != 0) {
            virReportSystemError(-rc,
                                 _("Unable to set swap hard limit for domain %s"),
                                 def->name);
            goto cleanup;
        }
    }

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    ret = 0;
cleanup:
    return ret;
}


static int lxcSetContainerDeviceACL(virCgroupPtr cgroup, virDomainDefPtr def)
{
    int ret = -1;
    int rc;
    size_t i;
    static const struct cgroup_device_policy devices[] = {
        {'c', LXC_DEV_MAJ_MEMORY, LXC_DEV_MIN_NULL},
        {'c', LXC_DEV_MAJ_MEMORY, LXC_DEV_MIN_ZERO},
        {'c', LXC_DEV_MAJ_MEMORY, LXC_DEV_MIN_FULL},
        {'c', LXC_DEV_MAJ_MEMORY, LXC_DEV_MIN_RANDOM},
        {'c', LXC_DEV_MAJ_MEMORY, LXC_DEV_MIN_URANDOM},
        {'c', LXC_DEV_MAJ_TTY, LXC_DEV_MIN_TTY},
        {'c', LXC_DEV_MAJ_TTY, LXC_DEV_MIN_PTMX},
        {0,   0, 0}};

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    rc = virCgroupDenyAllDevices(cgroup);
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    if (rc != 0) {
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        virReportSystemError(-rc,
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                             _("Unable to deny devices for domain %s"),
                             def->name);
        goto cleanup;
    }
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    for (i = 0; devices[i].type != 0; i++) {
597
        const struct cgroup_device_policy *dev = &devices[i];
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        rc = virCgroupAllowDevice(cgroup,
                                  dev->type,
                                  dev->major,
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                                  dev->minor,
                                  VIR_CGROUP_DEVICE_RWM);
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        if (rc != 0) {
604
            virReportSystemError(-rc,
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                                 _("Unable to allow device %c:%d:%d for domain %s"),
                                 dev->type, dev->major, dev->minor, def->name);
            goto cleanup;
        }
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    }

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    for (i = 0 ; i < def->nfss ; i++) {
        if (def->fss[i]->type != VIR_DOMAIN_FS_TYPE_BLOCK)
            continue;

        rc = virCgroupAllowDevicePath(cgroup,
                                      def->fss[i]->src,
                                      def->fss[i]->readonly ?
                                      VIR_CGROUP_DEVICE_READ :
                                      VIR_CGROUP_DEVICE_RW);
        if (rc != 0) {
            virReportSystemError(-rc,
                                 _("Unable to allow device %s for domain %s"),
                                 def->fss[i]->src, def->name);
            goto cleanup;
        }
    }

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    rc = virCgroupAllowDeviceMajor(cgroup, 'c', LXC_DEV_MAJ_PTY,
                                   VIR_CGROUP_DEVICE_RWM);
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    if (rc != 0) {
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        virReportSystemError(-rc,
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                             _("Unable to allow PTY devices for domain %s"),
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                             def->name);
        goto cleanup;
    }
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    ret = 0;
cleanup:
    return ret;
}


/**
 * lxcSetContainerResources
 * @def: pointer to virtual machine structure
 *
 * Creates a cgroup for the container, moves the task inside,
 * and sets resource limits
 *
 * Returns 0 on success or -1 in case of error
 */
static int lxcSetContainerResources(virDomainDefPtr def)
{
    virCgroupPtr driver;
    virCgroupPtr cgroup;
    int rc = -1;

    if (lxcSetContainerCpuAffinity(def) < 0)
        return -1;

    if (lxcSetContainerNUMAPolicy(def) < 0)
        return -1;

    rc = virCgroupForDriver("lxc", &driver, 1, 0);
    if (rc != 0) {
        /* Skip all if no driver cgroup is configured */
        if (rc == -ENXIO || rc == -ENOENT)
            return 0;

        virReportSystemError(-rc, "%s",
                             _("Unable to get cgroup for driver"));
        return rc;
    }

    rc = virCgroupForDomain(driver, def->name, &cgroup, 1);
    if (rc != 0) {
        virReportSystemError(-rc,
                             _("Unable to create cgroup for domain %s"),
                             def->name);
        goto cleanup;
    }

    if (lxcSetContainerCpuTune(cgroup, def) < 0)
        goto cleanup;

    if (lxcSetContainerBlkioTune(cgroup, def) < 0)
        goto cleanup;

    if (lxcSetContainerMemTune(cgroup, def) < 0)
        goto cleanup;

    if (lxcSetContainerDeviceACL(cgroup, def) < 0)
        goto cleanup;

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    rc = virCgroupAddTask(cgroup, getpid());
    if (rc != 0) {
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        virReportSystemError(-rc,
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                             _("Unable to add task %d to cgroup for domain %s"),
                             getpid(), def->name);
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    }

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cleanup:
    virCgroupFree(&driver);
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    virCgroupFree(&cgroup);

    return rc;
}

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static char*lxcMonitorPath(virLXCControllerPtr ctrl)
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{
    char *sockpath;
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    if (virAsprintf(&sockpath, "%s/%s.sock",
714
                    LXC_STATE_DIR, ctrl->def->name) < 0)
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        virReportOOMError();
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    return sockpath;
}

static int lxcMonitorServer(const char *sockpath)
{
    int fd;
    struct sockaddr_un addr;

    if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
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        virReportSystemError(errno,
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                             _("failed to create server socket '%s'"),
                             sockpath);
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        goto error;
    }

    unlink(sockpath);
    memset(&addr, 0, sizeof(addr));
    addr.sun_family = AF_UNIX;
C
Chris Lalancette 已提交
734
    if (virStrcpyStatic(addr.sun_path, sockpath) == NULL) {
735
        lxcError(VIR_ERR_INTERNAL_ERROR,
C
Chris Lalancette 已提交
736 737 738
                 _("Socket path %s too long for destination"), sockpath);
        goto error;
    }
739 740

    if (bind(fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
741
        virReportSystemError(errno,
742 743
                             _("failed to bind server socket '%s'"),
                             sockpath);
744 745 746
        goto error;
    }
    if (listen(fd, 30 /* backlog */ ) < 0) {
747
        virReportSystemError(errno,
748 749
                             _("failed to listen server socket %s"),
                             sockpath);
750 751 752 753 754 755
        goto error;
    }

    return fd;

error:
756
    VIR_FORCE_CLOSE(fd);
757 758
    return -1;
}
759

D
Daniel P. Berrange 已提交
760 761 762 763 764 765 766 767 768

static int lxcControllerClearCapabilities(void)
{
#if HAVE_CAPNG
    int ret;

    capng_clear(CAPNG_SELECT_BOTH);

    if ((ret = capng_apply(CAPNG_SELECT_BOTH)) < 0) {
769
        lxcError(VIR_ERR_INTERNAL_ERROR,
D
Daniel P. Berrange 已提交
770 771 772 773
                 _("failed to apply capabilities: %d"), ret);
        return -1;
    }
#else
774
    VIR_WARN("libcap-ng support not compiled in, unable to clear capabilities");
D
Daniel P. Berrange 已提交
775 776 777 778
#endif
    return 0;
}

779 780 781
/* Return true if it is ok to ignore an accept-after-epoll syscall
   that fails with the specified errno value.  Else false.  */
static bool
782
ignorable_accept_errno(int errnum)
783 784 785 786 787 788 789
{
  return (errnum == EINVAL
          || errnum == ECONNABORTED
          || errnum == EAGAIN
          || errnum == EWOULDBLOCK);
}

790 791 792 793 794 795 796 797 798 799 800 801
static bool quit = false;
static virMutex lock;
static int sigpipe[2];

static void lxcSignalChildHandler(int signum ATTRIBUTE_UNUSED)
{
    ignore_value(write(sigpipe[1], "1", 1));
}

static void lxcSignalChildIO(int watch ATTRIBUTE_UNUSED,
                             int fd ATTRIBUTE_UNUSED,
                             int events ATTRIBUTE_UNUSED, void *opaque)
802
{
803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821
    char buf[1];
    int ret;
    int *container = opaque;

    ignore_value(read(sigpipe[0], buf, 1));
    ret = waitpid(-1, NULL, WNOHANG);
    if (ret == *container) {
        virMutexLock(&lock);
        quit = true;
        virMutexUnlock(&lock);
    }
}


struct lxcConsole {

    int hostWatch;
    int hostFd;  /* PTY FD in the host OS */
    bool hostClosed;
822 823 824
    int hostEpoll;
    bool hostBlocking;

825 826 827
    int contWatch;
    int contFd;  /* PTY FD in the container */
    bool contClosed;
828 829 830 831 832
    int contEpoll;
    bool contBlocking;

    int epollWatch;
    int epollFd; /* epoll FD for dealing with EOF */
833 834 835 836 837 838 839 840 841 842 843 844 845

    size_t fromHostLen;
    char fromHostBuf[1024];
    size_t fromContLen;
    char fromContBuf[1024];
};

struct lxcMonitor {
    int serverWatch;
    int serverFd;  /* Server listen socket */
    int clientWatch;
    int clientFd;  /* Current client FD (if any) */
};
846 847


848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927
static void lxcClientIO(int watch ATTRIBUTE_UNUSED, int fd, int events, void *opaque)
{
    struct lxcMonitor *monitor = opaque;
    char buf[1024];
    ssize_t ret;

    if (events & (VIR_EVENT_HANDLE_HANGUP |
                  VIR_EVENT_HANDLE_ERROR)) {
        virEventRemoveHandle(monitor->clientWatch);
        monitor->clientWatch = -1;
        return;
    }

reread:
    ret = read(fd, buf, sizeof(buf));
    if (ret == -1 && errno == EINTR)
        goto reread;
    if (ret == -1 && errno == EAGAIN)
        return;
    if (ret == -1) {
        lxcError(VIR_ERR_INTERNAL_ERROR, "%s",
                 _("Unable to read from monitor client"));
        virMutexLock(&lock);
        quit = true;
        virMutexUnlock(&lock);
        return;
    }
    if (ret == 0) {
        VIR_DEBUG("Client %d gone", fd);
        VIR_FORCE_CLOSE(monitor->clientFd);
        virEventRemoveHandle(monitor->clientWatch);
        monitor->clientWatch = -1;
    }
}


static void lxcServerAccept(int watch ATTRIBUTE_UNUSED, int fd, int events ATTRIBUTE_UNUSED, void *opaque)
{
    struct lxcMonitor *monitor = opaque;
    int client;

    if ((client = accept(fd, NULL, NULL)) < 0) {
        /* First reflex may be simply to declare accept failure
           to be a fatal error.  However, accept may fail when
           a client quits between the above poll and here.
           That case is not fatal, but rather to be expected,
           if not common, so ignore it.  */
        if (ignorable_accept_errno(errno))
            return;
        virReportSystemError(errno, "%s",
                             _("Unable to accept monitor client"));
        virMutexLock(&lock);
        quit = true;
        virMutexUnlock(&lock);
        return;
    }
    VIR_DEBUG("New client %d (old %d)\n", client, monitor->clientFd);
    VIR_FORCE_CLOSE(monitor->clientFd);
    virEventRemoveHandle(monitor->clientWatch);

    monitor->clientFd = client;
    if ((monitor->clientWatch = virEventAddHandle(monitor->clientFd,
                                                  VIR_EVENT_HANDLE_READABLE,
                                                  lxcClientIO,
                                                  monitor,
                                                  NULL)) < 0) {
        lxcError(VIR_ERR_INTERNAL_ERROR, "%s",
                 _("Unable to watch client socket"));
        virMutexLock(&lock);
        quit = true;
        virMutexUnlock(&lock);
        return;
    }
}

static void lxcConsoleUpdateWatch(struct lxcConsole *console)
{
    int hostEvents = 0;
    int contEvents = 0;

928
    if (!console->hostClosed || (!console->hostBlocking && console->fromContLen)) {
929 930 931 932 933
        if (console->fromHostLen < sizeof(console->fromHostBuf))
            hostEvents |= VIR_EVENT_HANDLE_READABLE;
        if (console->fromContLen)
            hostEvents |= VIR_EVENT_HANDLE_WRITABLE;
    }
934
    if (!console->contClosed || (!console->contBlocking && console->fromHostLen)) {
935 936 937 938 939 940
        if (console->fromContLen < sizeof(console->fromContBuf))
            contEvents |= VIR_EVENT_HANDLE_READABLE;
        if (console->fromHostLen)
            contEvents |= VIR_EVENT_HANDLE_WRITABLE;
    }

941 942 943
    VIR_DEBUG("Container watch %d=%d host watch %d=%d",
              console->contWatch, contEvents,
              console->hostWatch, hostEvents);
944 945
    virEventUpdateHandle(console->contWatch, contEvents);
    virEventUpdateHandle(console->hostWatch, hostEvents);
946

947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982
    if (console->hostClosed) {
        int events = EPOLLIN | EPOLLET;
        if (console->hostBlocking)
            events |= EPOLLOUT;

        if (events != console->hostEpoll) {
            struct epoll_event event;
            int action = EPOLL_CTL_ADD;
            if (console->hostEpoll)
                action = EPOLL_CTL_MOD;

            VIR_DEBUG("newHostEvents=%x oldHostEvents=%x", events, console->hostEpoll);

            event.events = events;
            event.data.fd = console->hostFd;
            if (epoll_ctl(console->epollFd, action, console->hostFd, &event) < 0) {
                VIR_DEBUG(":fail");
                virReportSystemError(errno, "%s",
                                     _("Unable to add epoll fd"));
                quit = true;
                goto cleanup;
            }
            console->hostEpoll = events;
            VIR_DEBUG("newHostEvents=%x oldHostEvents=%x", events, console->hostEpoll);
        }
    } else if (console->hostEpoll) {
        VIR_DEBUG("Stop epoll oldContEvents=%x", console->hostEpoll);
        if (epoll_ctl(console->epollFd, EPOLL_CTL_DEL, console->hostFd, NULL) < 0) {
            virReportSystemError(errno, "%s",
                                 _("Unable to remove epoll fd"));
                VIR_DEBUG(":fail");
            quit = true;
            goto cleanup;
        }
        console->hostEpoll = 0;
    }
983

984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022
    if (console->contClosed) {
        int events = EPOLLIN | EPOLLET;
        if (console->contBlocking)
            events |= EPOLLOUT;

        if (events != console->contEpoll) {
            struct epoll_event event;
            int action = EPOLL_CTL_ADD;
            if (console->contEpoll)
                action = EPOLL_CTL_MOD;

            VIR_DEBUG("newContEvents=%x oldContEvents=%x", events, console->contEpoll);

            event.events = events;
            event.data.fd = console->contFd;
            if (epoll_ctl(console->epollFd, action, console->contFd, &event) < 0) {
                virReportSystemError(errno, "%s",
                                     _("Unable to add epoll fd"));
                VIR_DEBUG(":fail");
                quit = true;
                goto cleanup;
            }
            console->contEpoll = events;
            VIR_DEBUG("newHostEvents=%x oldHostEvents=%x", events, console->contEpoll);
        }
    } else if (console->contEpoll) {
        VIR_DEBUG("Stop epoll oldContEvents=%x", console->contEpoll);
        if (epoll_ctl(console->epollFd, EPOLL_CTL_DEL, console->contFd, NULL) < 0) {
            virReportSystemError(errno, "%s",
                                 _("Unable to remove epoll fd"));
                VIR_DEBUG(":fail");
            quit = true;
            goto cleanup;
        }
        console->contEpoll = 0;
    }
cleanup:
    return;
}
1023 1024


1025
static void lxcEpollIO(int watch, int fd, int events, void *opaque)
1026
{
1027
    struct lxcConsole *console = opaque;
1028

1029 1030 1031 1032 1033 1034 1035 1036 1037 1038
    virMutexLock(&lock);
    VIR_DEBUG("IO event watch=%d fd=%d events=%d fromHost=%zu fromcont=%zu",
              watch, fd, events,
              console->fromHostLen,
              console->fromContLen);

    while (1) {
        struct epoll_event event;
        int ret;
        ret = epoll_wait(console->epollFd, &event, 1, 0);
1039
        if (ret < 0) {
S
Stefan Berger 已提交
1040
            if (errno == EINTR)
1041 1042 1043 1044 1045 1046 1047
                continue;
            virReportSystemError(errno, "%s",
                                 _("Unable to wait on epoll"));
            quit = true;
            goto cleanup;
        }

1048 1049 1050 1051 1052 1053 1054
        if (ret == 0)
            break;

        VIR_DEBUG("fd=%d hostFd=%d contFd=%d hostEpoll=%x contEpoll=%x",
                  event.data.fd, console->hostFd, console->contFd,
                  console->hostEpoll, console->contEpoll);

1055 1056 1057
        /* If we get HUP+dead PID, we just re-enable the main loop
         * which will see the PID has died and exit */
        if ((event.events & EPOLLIN)) {
1058 1059
            if (event.data.fd == console->hostFd) {
                console->hostClosed = false;
1060
            } else {
1061
                console->contClosed = false;
1062
            }
1063
            lxcConsoleUpdateWatch(console);
1064 1065 1066 1067 1068
            break;
        }
    }

cleanup:
1069
    virMutexUnlock(&lock);
1070 1071 1072 1073 1074 1075 1076
}

static void lxcConsoleIO(int watch, int fd, int events, void *opaque)
{
    struct lxcConsole *console = opaque;

    virMutexLock(&lock);
1077 1078 1079 1080
    VIR_DEBUG("IO event watch=%d fd=%d events=%d fromHost=%zu fromcont=%zu",
              watch, fd, events,
              console->fromHostLen,
              console->fromContLen);
1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136
    if (events & VIR_EVENT_HANDLE_READABLE) {
        char *buf;
        size_t *len;
        size_t avail;
        ssize_t done;
        if (watch == console->hostWatch) {
            buf = console->fromHostBuf;
            len = &console->fromHostLen;
            avail = sizeof(console->fromHostBuf) - *len;
        } else {
            buf = console->fromContBuf;
            len = &console->fromContLen;
            avail = sizeof(console->fromContBuf) - *len;
        }
    reread:
        done = read(fd, buf + *len, avail);
        if (done == -1 && errno == EINTR)
            goto reread;
        if (done == -1 && errno != EAGAIN) {
            virReportSystemError(errno, "%s",
                                 _("Unable to read container pty"));
            goto error;
        }
        if (done > 0) {
            *len += done;
        } else {
            VIR_DEBUG("Read fd %d done %d errno %d", fd, (int)done, errno);
        }
    }

    if (events & VIR_EVENT_HANDLE_WRITABLE) {
        char *buf;
        size_t *len;
        ssize_t done;
        if (watch == console->hostWatch) {
            buf = console->fromContBuf;
            len = &console->fromContLen;
        } else {
            buf = console->fromHostBuf;
            len = &console->fromHostLen;
        }

    rewrite:
        done = write(fd, buf, *len);
        if (done == -1 && errno == EINTR)
            goto rewrite;
        if (done == -1 && errno != EAGAIN) {
            virReportSystemError(errno, "%s",
                                 _("Unable to write to container pty"));
            goto error;
        }
        if (done > 0) {
            memmove(buf, buf + done, (*len - done));
            *len -= done;
        } else {
            VIR_DEBUG("Write fd %d done %d errno %d", fd, (int)done, errno);
1137 1138 1139 1140
            if (watch == console->hostWatch)
                console->hostBlocking = true;
            else
                console->contBlocking = true;
1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165
        }
    }

    if (events & VIR_EVENT_HANDLE_HANGUP) {
        if (watch == console->hostWatch) {
            console->hostClosed = true;
        } else {
            console->contClosed = true;
        }
        VIR_DEBUG("Got EOF on %d %d", watch, fd);
    }

    lxcConsoleUpdateWatch(console);
    virMutexUnlock(&lock);
    return;

error:
    virEventRemoveHandle(console->contWatch);
    virEventRemoveHandle(console->hostWatch);
    console->contWatch = console->hostWatch = -1;
    quit = true;
    virMutexUnlock(&lock);
}


1166
/**
1167
 * lxcControllerMain
1168 1169 1170 1171
 * @serverFd: server socket fd to accept client requests
 * @clientFd: initial client which is the libvirtd daemon
 * @hostFd: open fd for application facing Pty
 * @contFd: open fd for container facing Pty
1172
 *
1173
 * Processes I/O on consoles and the monitor
1174 1175 1176
 *
 * Returns 0 on success or -1 in case of error
 */
1177 1178
static int lxcControllerMain(int serverFd,
                             int clientFd,
1179 1180 1181
                             int *hostFds,
                             int *contFds,
                             size_t nFds,
1182
                             pid_t container)
1183
{
S
Stefan Berger 已提交
1184
    struct lxcConsole *consoles = NULL;
1185 1186 1187 1188 1189
    struct lxcMonitor monitor = {
        .serverFd = serverFd,
        .clientFd = clientFd,
    };
    virErrorPtr err;
1190
    int rc = -1;
1191
    size_t i;
1192 1193 1194 1195 1196

    if (virMutexInit(&lock) < 0)
        goto cleanup2;

    if (pipe2(sigpipe, O_CLOEXEC|O_NONBLOCK) < 0) {
1197
        virReportSystemError(errno, "%s",
1198
                             _("Cannot create signal pipe"));
1199 1200 1201
        goto cleanup;
    }

1202 1203 1204 1205 1206 1207 1208
    if (virEventAddHandle(sigpipe[0],
                          VIR_EVENT_HANDLE_READABLE,
                          lxcSignalChildIO,
                          &container,
                          NULL) < 0) {
        lxcError(VIR_ERR_INTERNAL_ERROR, "%s",
                 _("Unable to watch signal pipe"));
1209 1210
        goto cleanup;
    }
1211 1212

    if (signal(SIGCHLD, lxcSignalChildHandler) == SIG_ERR) {
1213
        virReportSystemError(errno, "%s",
1214
                             _("Cannot install signal handler"));
1215 1216 1217
        goto cleanup;
    }

1218 1219
    VIR_DEBUG("serverFd=%d clientFd=%d",
              serverFd, clientFd);
1220 1221 1222 1223 1224 1225 1226 1227 1228
    virResetLastError();

    if ((monitor.serverWatch = virEventAddHandle(monitor.serverFd,
                                                 VIR_EVENT_HANDLE_READABLE,
                                                 lxcServerAccept,
                                                 &monitor,
                                                 NULL)) < 0) {
        lxcError(VIR_ERR_INTERNAL_ERROR, "%s",
                 _("Unable to watch monitor socket"));
1229 1230 1231
        goto cleanup;
    }

1232 1233 1234 1235 1236 1237 1238 1239
    if (monitor.clientFd != -1 &&
        (monitor.clientWatch = virEventAddHandle(monitor.clientFd,
                                                 VIR_EVENT_HANDLE_READABLE,
                                                 lxcClientIO,
                                                 &monitor,
                                                 NULL)) < 0) {
        lxcError(VIR_ERR_INTERNAL_ERROR, "%s",
                 _("Unable to watch client socket"));
1240 1241 1242
        goto cleanup;
    }

1243 1244
    if (VIR_ALLOC_N(consoles, nFds) < 0) {
        virReportOOMError();
1245 1246
        goto cleanup;
    }
1247

1248 1249 1250 1251 1252 1253 1254
    for (i = 0 ; i < nFds ; i++) {
        consoles[i].epollFd = -1;
        consoles[i].epollWatch = -1;
        consoles[i].hostWatch = -1;
        consoles[i].contWatch = -1;
    }

1255 1256 1257 1258
    for (i = 0 ; i < nFds ; i++) {
        consoles[i].hostFd = hostFds[i];
        consoles[i].contFd = contFds[i];

1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274
        if ((consoles[i].epollFd = epoll_create1(EPOLL_CLOEXEC)) < 0) {
            virReportSystemError(errno, "%s",
                                 _("Unable to create epoll fd"));
            goto cleanup;
        }

        if ((consoles[i].epollWatch = virEventAddHandle(consoles[i].epollFd,
                                                        VIR_EVENT_HANDLE_READABLE,
                                                        lxcEpollIO,
                                                        &consoles[i],
                                                        NULL)) < 0) {
            lxcError(VIR_ERR_INTERNAL_ERROR, "%s",
                     _("Unable to watch epoll FD"));
            goto cleanup;
        }

1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293
        if ((consoles[i].hostWatch = virEventAddHandle(consoles[i].hostFd,
                                                       VIR_EVENT_HANDLE_READABLE,
                                                       lxcConsoleIO,
                                                       &consoles[i],
                                                       NULL)) < 0) {
            lxcError(VIR_ERR_INTERNAL_ERROR, "%s",
                     _("Unable to watch host console PTY"));
            goto cleanup;
        }

        if ((consoles[i].contWatch = virEventAddHandle(consoles[i].contFd,
                                                       VIR_EVENT_HANDLE_READABLE,
                                                       lxcConsoleIO,
                                                       &consoles[i],
                                                       NULL)) < 0) {
            lxcError(VIR_ERR_INTERNAL_ERROR, "%s",
                     _("Unable to watch host console PTY"));
            goto cleanup;
        }
1294
    }
1295

1296 1297 1298 1299
    virMutexLock(&lock);
    while (!quit) {
        virMutexUnlock(&lock);
        if (virEventRunDefaultImpl() < 0)
1300
            goto cleanup;
1301
        virMutexLock(&lock);
1302
    }
1303
    virMutexUnlock(&lock);
1304

1305 1306 1307
    err = virGetLastError();
    if (!err || err->code == VIR_ERR_OK)
        rc = 0;
1308 1309

cleanup:
1310 1311 1312 1313 1314
    virMutexDestroy(&lock);
    signal(SIGCHLD, SIG_DFL);
cleanup2:
    VIR_FORCE_CLOSE(monitor.serverFd);
    VIR_FORCE_CLOSE(monitor.clientFd);
1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325

    for (i = 0 ; i < nFds ; i++) {
        if (consoles[i].epollWatch != -1)
            virEventRemoveHandle(consoles[i].epollWatch);
        VIR_FORCE_CLOSE(consoles[i].epollFd);
        if (consoles[i].contWatch != -1)
            virEventRemoveHandle(consoles[i].contWatch);
        if (consoles[i].hostWatch != -1)
            virEventRemoveHandle(consoles[i].hostWatch);
    }

1326
    VIR_FREE(consoles);
1327 1328 1329
    return rc;
}

1330 1331 1332


/**
1333
 * virLXCControllerMoveInterfaces
1334 1335 1336 1337 1338 1339 1340 1341
 * @nveths: number of interfaces
 * @veths: interface names
 * @container: pid of container
 *
 * Moves network interfaces into a container's namespace
 *
 * Returns 0 on success or -1 in case of error
 */
1342 1343
static int virLXCControllerMoveInterfaces(virLXCControllerPtr ctrl,
                                          pid_t container)
1344
{
1345 1346 1347 1348
    size_t i;

    for (i = 0 ; i < ctrl->nveths ; i++) {
        if (virNetDevSetNamespace(ctrl->veths[i], container) < 0)
1349
            return -1;
1350
    }
1351 1352 1353 1354 1355 1356

    return 0;
}


/**
1357 1358
 * virLXCControllerDeleteInterfaces:
 * @ctrl: the LXC controller
1359 1360 1361 1362 1363
 *
 * Cleans up the container interfaces by deleting the veth device pairs.
 *
 * Returns 0 on success or -1 in case of error
 */
1364
static int virLXCControllerDeleteInterfaces(virLXCControllerPtr ctrl)
1365
{
1366 1367
    size_t i;
    int ret = 0;
1368

1369 1370 1371 1372 1373 1374
    for (i = 0 ; i < ctrl->nveths ; i++) {
        if (virNetDevVethDelete(ctrl->veths[i]) < 0)
            ret = -1;
    }

    return ret;
1375 1376
}

1377

1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396
static int lxcSetPersonality(virDomainDefPtr def)
{
    struct utsname utsname;
    const char *altArch;

    uname(&utsname);

    altArch = lxcContainerGetAlt32bitArch(utsname.machine);
    if (altArch &&
        STREQ(def->os.arch, altArch)) {
        if (personality(PER_LINUX32) < 0) {
            virReportSystemError(errno, _("Unable to request personality for %s on %s"),
                                 altArch, utsname.machine);
            return -1;
        }
    }
    return 0;
}

1397
#ifndef MS_REC
1398
# define MS_REC          16384
1399 1400 1401
#endif

#ifndef MS_SLAVE
1402
# define MS_SLAVE              (1<<19)
1403
#endif
1404

1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448
/* Create a private tty using the private devpts at PTMX, returning
 * the master in *TTYMASTER and the name of the slave, _from the
 * perspective of the guest after remounting file systems_, in
 * *TTYNAME.  Heavily borrowed from glibc, but doesn't require that
 * devpts == "/dev/pts" */
static int
lxcCreateTty(char *ptmx, int *ttymaster, char **ttyName)
{
    int ret = -1;
    int ptyno;
    int unlock = 0;

    if ((*ttymaster = open(ptmx, O_RDWR|O_NOCTTY|O_NONBLOCK)) < 0)
        goto cleanup;

    if (ioctl(*ttymaster, TIOCSPTLCK, &unlock) < 0)
        goto cleanup;

    if (ioctl(*ttymaster, TIOCGPTN, &ptyno) < 0)
        goto cleanup;

    /* If mount() succeeded at honoring newinstance, then the kernel
     * was new enough to also honor the mode=0620,gid=5 options, which
     * guarantee that the new pty already has correct permissions; so
     * while glibc has to fstat(), fchmod(), and fchown() for older
     * kernels, we can skip those steps.  ptyno shouldn't currently be
     * anything other than 0, but let's play it safe.  */
    if (virAsprintf(ttyName, "/dev/pts/%d", ptyno) < 0) {
        virReportOOMError();
        errno = ENOMEM;
        goto cleanup;
    }

    ret = 0;

cleanup:
    if (ret != 0) {
        VIR_FORCE_CLOSE(*ttymaster);
        VIR_FREE(*ttyName);
    }

    return ret;
}

1449
static int
1450 1451 1452 1453 1454 1455 1456
virLXCControllerRun(virLXCControllerPtr ctrl,
                    virSecurityManagerPtr securityDriver,
                    int monitor,
                    int client,
                    int *ttyFDs,
                    size_t nttyFDs,
                    int handshakefd)
1457 1458 1459
{
    int rc = -1;
    int control[2] = { -1, -1};
1460
    int containerhandshake[2] = { -1, -1 };
1461 1462
    int *containerTtyFDs = NULL;
    char **containerTtyPaths = NULL;
1463
    pid_t container = -1;
1464 1465 1466
    virDomainFSDefPtr root;
    char *devpts = NULL;
    char *devptmx = NULL;
1467 1468 1469
    size_t nloopDevs = 0;
    int *loopDevs = NULL;
    size_t i;
1470
    char *mount_options = NULL;
1471

1472 1473 1474 1475 1476 1477 1478 1479 1480
    if (VIR_ALLOC_N(containerTtyFDs, nttyFDs) < 0) {
        virReportOOMError();
        goto cleanup;
    }
    if (VIR_ALLOC_N(containerTtyPaths, nttyFDs) < 0) {
        virReportOOMError();
        goto cleanup;
    }

1481
    if (socketpair(PF_UNIX, SOCK_STREAM, 0, control) < 0) {
1482
        virReportSystemError(errno, "%s",
1483
                             _("sockpair failed"));
1484 1485 1486
        goto cleanup;
    }

1487 1488 1489 1490 1491 1492
    if (socketpair(PF_UNIX, SOCK_STREAM, 0, containerhandshake) < 0) {
        virReportSystemError(errno, "%s",
                             _("socketpair failed"));
        goto cleanup;
    }

1493
    if (lxcSetupLoopDevices(ctrl->def, &nloopDevs, &loopDevs) < 0)
1494 1495
        goto cleanup;

1496
    root = virDomainGetRootFilesystem(ctrl->def);
1497

1498
    if (lxcSetContainerResources(ctrl->def) < 0)
1499 1500
        goto cleanup;

1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521
    /*
     * If doing a chroot style setup, we need to prepare
     * a private /dev/pts for the child now, which they
     * will later move into position.
     *
     * This is complex because 'virsh console' needs to
     * use /dev/pts from the host OS, and the guest OS
     * needs to use /dev/pts from the guest.
     *
     * This means that we (libvirt_lxc) need to see and
     * use both /dev/pts instances. We're running in the
     * host OS context though and don't want to expose
     * the guest OS /dev/pts there.
     *
     * Thus we call unshare(CLONE_NS) so that we can see
     * the guest's new /dev/pts, without it becoming
     * visible to the host OS. We also put the root FS
     * into slave mode, just in case it was currently
     * marked as shared
     */
    if (root) {
1522
        mount_options = virSecurityManagerGetMountOptions(securityDriver, ctrl->def);
1523
        char *opts;
1524
        VIR_DEBUG("Setting up private /dev/pts");
1525 1526 1527 1528 1529 1530 1531 1532

        if (!virFileExists(root->src)) {
            virReportSystemError(errno,
                                 _("root source %s does not exist"),
                                 root->src);
            goto cleanup;
        }

1533
        if (unshare(CLONE_NEWNS) < 0) {
1534
            virReportSystemError(errno, "%s",
1535
                                 _("Cannot unshare mount namespace"));
1536 1537 1538 1539
            goto cleanup;
        }

        if (mount("", "/", NULL, MS_SLAVE|MS_REC, NULL) < 0) {
1540
            virReportSystemError(errno, "%s",
1541
                                 _("Failed to switch root mount into slave mode"));
1542 1543 1544 1545 1546
            goto cleanup;
        }

        if (virAsprintf(&devpts, "%s/dev/pts", root->src) < 0 ||
            virAsprintf(&devptmx, "%s/dev/pts/ptmx", root->src) < 0) {
1547
            virReportOOMError();
1548 1549 1550
            goto cleanup;
        }

1551
        if (virFileMakePath(devpts) < 0) {
1552
            virReportSystemError(errno,
1553
                                 _("Failed to make path %s"),
1554 1555 1556 1557
                                 devpts);
            goto cleanup;
        }

1558 1559
        /* XXX should we support gid=X for X!=5 for distros which use
         * a different gid for tty?  */
1560 1561
        if (virAsprintf(&opts, "newinstance,ptmxmode=0666,mode=0620,gid=5%s",
                        (mount_options ? mount_options : "")) < 0) {
1562 1563 1564 1565 1566 1567 1568 1569
            virReportOOMError();
            goto cleanup;
        }

        VIR_DEBUG("Mount devpts on %s type=tmpfs flags=%x, opts=%s",
                  devpts, MS_NOSUID, opts);
        if (mount("devpts", devpts, "devpts", MS_NOSUID, opts) < 0) {
            VIR_FREE(opts);
1570
            virReportSystemError(errno,
1571
                                 _("Failed to mount devpts on %s"),
1572 1573 1574
                                 devpts);
            goto cleanup;
        }
1575
        VIR_FREE(opts);
1576 1577

        if (access(devptmx, R_OK) < 0) {
1578
            VIR_WARN("Kernel does not support private devpts, using shared devpts");
1579 1580 1581
            VIR_FREE(devptmx);
        }
    } else {
1582 1583 1584
        if (nttyFDs != 1) {
            lxcError(VIR_ERR_CONFIG_UNSUPPORTED,
                     _("Expected exactly one TTY fd, but got %zu"), nttyFDs);
1585 1586 1587 1588
            goto cleanup;
        }
    }

1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610
    for (i = 0 ; i < nttyFDs ; i++) {
        if (devptmx) {
            VIR_DEBUG("Opening tty on private %s", devptmx);
            if (lxcCreateTty(devptmx,
                             &containerTtyFDs[i],
                             &containerTtyPaths[i]) < 0) {
                virReportSystemError(errno, "%s",
                                     _("Failed to allocate tty"));
                goto cleanup;
            }
        } else {
            VIR_DEBUG("Opening tty on shared /dev/ptmx");
            if (virFileOpenTty(&containerTtyFDs[i],
                               &containerTtyPaths[i],
                               0) < 0) {
                virReportSystemError(errno, "%s",
                                     _("Failed to allocate tty"));
                goto cleanup;
            }
        }
    }

1611
    if (lxcSetPersonality(ctrl->def) < 0)
1612
        goto cleanup;
1613

1614
    if ((container = lxcContainerStart(ctrl->def,
1615
                                       securityDriver,
1616 1617
                                       ctrl->nveths,
                                       ctrl->veths,
1618
                                       control[1],
1619
                                       containerhandshake[1],
1620 1621
                                       containerTtyPaths,
                                       nttyFDs)) < 0)
1622
        goto cleanup;
1623
    VIR_FORCE_CLOSE(control[1]);
1624
    VIR_FORCE_CLOSE(containerhandshake[1]);
1625

1626
    if (virLXCControllerMoveInterfaces(ctrl, container) < 0)
1627 1628
        goto cleanup;

1629 1630 1631
    if (lxcContainerSendContinue(control[0]) < 0) {
        virReportSystemError(errno, "%s",
                             _("Unable to send container continue message"));
1632
        goto cleanup;
1633
    }
1634

1635 1636 1637 1638 1639 1640
    if (lxcContainerWaitForContinue(containerhandshake[0]) < 0) {
        virReportSystemError(errno, "%s",
                             _("error receiving signal from container"));
        goto cleanup;
    }

1641 1642 1643 1644 1645 1646 1647 1648
    /* Now the container is fully setup... */

    /* ...we can close the loop devices... */

    for (i = 0 ; i < nloopDevs ; i++)
        VIR_FORCE_CLOSE(loopDevs[i]);

    /* ...and reduce our privileges */
D
Daniel P. Berrange 已提交
1649 1650 1651
    if (lxcControllerClearCapabilities() < 0)
        goto cleanup;

1652 1653 1654 1655 1656 1657 1658
    if (lxcContainerSendContinue(handshakefd) < 0) {
        virReportSystemError(errno, "%s",
                             _("error sending continue signal to parent"));
        goto cleanup;
    }
    VIR_FORCE_CLOSE(handshakefd);

1659
    if (virSetBlocking(monitor, false) < 0 ||
1660
        virSetBlocking(client, false) < 0) {
1661
        virReportSystemError(errno, "%s",
1662
                             _("Unable to set file descriptor non-blocking"));
1663 1664
        goto cleanup;
    }
1665 1666 1667 1668
    for (i = 0 ; i < nttyFDs ; i++) {
        if (virSetBlocking(ttyFDs[i], false) < 0 ||
            virSetBlocking(containerTtyFDs[i], false) < 0) {
            virReportSystemError(errno, "%s",
1669
                                 _("Unable to set file descriptor non-blocking"));
1670 1671 1672
            goto cleanup;
        }
    }
1673

1674 1675
    rc = lxcControllerMain(monitor, client, ttyFDs, containerTtyFDs, nttyFDs, container);
    monitor = client = -1;
1676 1677

cleanup:
1678
    VIR_FREE(mount_options);
1679 1680
    VIR_FREE(devptmx);
    VIR_FREE(devpts);
1681 1682
    VIR_FORCE_CLOSE(control[0]);
    VIR_FORCE_CLOSE(control[1]);
1683
    VIR_FORCE_CLOSE(handshakefd);
1684 1685
    VIR_FORCE_CLOSE(containerhandshake[0]);
    VIR_FORCE_CLOSE(containerhandshake[1]);
1686

1687 1688 1689 1690 1691 1692
    for (i = 0 ; i < nttyFDs ; i++)
        VIR_FREE(containerTtyPaths[i]);
    VIR_FREE(containerTtyPaths);
    for (i = 0 ; i < nttyFDs ; i++)
        VIR_FORCE_CLOSE(containerTtyFDs[i]);
    VIR_FREE(containerTtyFDs);
1693

1694 1695
    for (i = 0 ; i < nloopDevs ; i++)
        VIR_FORCE_CLOSE(loopDevs[i]);
1696 1697
    VIR_FREE(loopDevs);

1698 1699
    virPidAbort(container);

1700 1701 1702 1703
    return rc;
}


1704
int main(int argc, char *argv[])
1705 1706
{
    pid_t pid;
1707
    int rc = 1;
1708
    int client;
1709
    char *name = NULL;
1710
    size_t nveths = 0;
1711 1712
    char **veths = NULL;
    int monitor = -1;
1713
    int handshakefd = -1;
1714 1715
    int bg = 0;
    char *sockpath = NULL;
1716
    const struct option options[] = {
1717 1718 1719 1720
        { "background", 0, NULL, 'b' },
        { "name",   1, NULL, 'n' },
        { "veth",   1, NULL, 'v' },
        { "console", 1, NULL, 'c' },
1721
        { "handshakefd", 1, NULL, 's' },
1722
        { "security", 1, NULL, 'S' },
1723 1724 1725
        { "help", 0, NULL, 'h' },
        { 0, 0, 0, 0 },
    };
1726 1727
    int *ttyFDs = NULL;
    size_t nttyFDs = 0;
1728
    virSecurityManagerPtr securityDriver = NULL;
1729
    virLXCControllerPtr ctrl = NULL;
1730

E
Eric Blake 已提交
1731 1732
    if (setlocale(LC_ALL, "") == NULL ||
        bindtextdomain(PACKAGE, LOCALEDIR) == NULL ||
1733 1734
        textdomain(PACKAGE) == NULL ||
        virRandomInitialize(time(NULL) ^ getpid())) {
E
Eric Blake 已提交
1735 1736 1737 1738
        fprintf(stderr, _("%s: initialization failed\n"), argv[0]);
        exit(EXIT_FAILURE);
    }

1739 1740 1741
    /* Initialize logging */
    virLogSetFromEnv();

1742 1743
    while (1) {
        int c;
1744

1745
        c = getopt_long(argc, argv, "dn:v:m:c:s:h:S:",
1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757
                       options, NULL);

        if (c == -1)
            break;

        switch (c) {
        case 'b':
            bg = 1;
            break;

        case 'n':
            if ((name = strdup(optarg)) == NULL) {
1758
                virReportOOMError();
1759
                goto cleanup;
1760
            }
1761 1762 1763 1764
            break;

        case 'v':
            if (VIR_REALLOC_N(veths, nveths+1) < 0) {
1765
                virReportOOMError();
1766
                goto cleanup;
1767
            }
1768
            if ((veths[nveths++] = strdup(optarg)) == NULL) {
1769
                virReportOOMError();
1770
                goto cleanup;
1771
            }
1772 1773 1774
            break;

        case 'c':
1775 1776 1777 1778 1779
            if (VIR_REALLOC_N(ttyFDs, nttyFDs + 1) < 0) {
                virReportOOMError();
                goto cleanup;
            }
            if (virStrToLong_i(optarg, NULL, 10, &ttyFDs[nttyFDs++]) < 0) {
1780 1781 1782 1783 1784
                fprintf(stderr, "malformed --console argument '%s'", optarg);
                goto cleanup;
            }
            break;

1785 1786 1787 1788 1789 1790 1791 1792
        case 's':
            if (virStrToLong_i(optarg, NULL, 10, &handshakefd) < 0) {
                fprintf(stderr, "malformed --handshakefd argument '%s'",
                        optarg);
                goto cleanup;
            }
            break;

1793
        case 'S':
1794 1795 1796
            if (!(securityDriver = virSecurityManagerNew(optarg,
                                                         LXC_DRIVER_NAME,
                                                         false, false, false))) {
1797 1798 1799 1800 1801 1802
                fprintf(stderr, "Cannot create security manager '%s'",
                        optarg);
                goto cleanup;
            }
            break;

1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813
        case 'h':
        case '?':
            fprintf(stderr, "\n");
            fprintf(stderr, "syntax: %s [OPTIONS]\n", argv[0]);
            fprintf(stderr, "\n");
            fprintf(stderr, "Options\n");
            fprintf(stderr, "\n");
            fprintf(stderr, "  -b, --background\n");
            fprintf(stderr, "  -n NAME, --name NAME\n");
            fprintf(stderr, "  -c FD, --console FD\n");
            fprintf(stderr, "  -v VETH, --veth VETH\n");
1814
            fprintf(stderr, "  -s FD, --handshakefd FD\n");
1815
            fprintf(stderr, "  -S NAME, --security NAME\n");
1816 1817 1818
            fprintf(stderr, "  -h, --help\n");
            fprintf(stderr, "\n");
            goto cleanup;
1819 1820 1821
        }
    }

1822
    if (securityDriver == NULL) {
1823 1824 1825
        if (!(securityDriver = virSecurityManagerNew("none",
                                                     LXC_DRIVER_NAME,
                                                     false, false, false))) {
1826 1827 1828 1829 1830
            fprintf(stderr, "%s: cannot initialize nop security manager", argv[0]);
            goto cleanup;
        }
    }

1831

1832 1833 1834 1835 1836
    if (name == NULL) {
        fprintf(stderr, "%s: missing --name argument for configuration\n", argv[0]);
        goto cleanup;
    }

1837 1838 1839 1840 1841 1842
    if (handshakefd < 0) {
        fprintf(stderr, "%s: missing --handshake argument for container PTY\n",
                argv[0]);
        goto cleanup;
    }

1843
    if (getuid() != 0) {
1844 1845 1846
        fprintf(stderr, "%s: must be run as the 'root' user\n", argv[0]);
        goto cleanup;
    }
1847

1848 1849
    virEventRegisterDefaultImpl();

1850
    if (!(ctrl = virLXCControllerNew(name)))
1851
        goto cleanup;
1852

1853
    VIR_DEBUG("Security model %s type %s label %s imagelabel %s",
1854 1855 1856 1857
              NULLSTR(ctrl->def->seclabel.model),
              virDomainSeclabelTypeToString(ctrl->def->seclabel.type),
              NULLSTR(ctrl->def->seclabel.label),
              NULLSTR(ctrl->def->seclabel.imagelabel));
1858

1859 1860 1861 1862
    ctrl->veths = veths;
    ctrl->nveths = nveths;

    if (virLXCControllerValidateNICs(ctrl) < 0)
1863
        goto cleanup;
1864

1865
    if ((sockpath = lxcMonitorPath(ctrl)) == NULL)
1866
        goto cleanup;
1867

1868 1869
    if ((monitor = lxcMonitorServer(sockpath)) < 0)
        goto cleanup;
1870

1871 1872 1873
    if (bg) {
        if ((pid = fork()) < 0)
            goto cleanup;
1874

1875
        if (pid > 0) {
1876
            if ((rc = virPidFileWrite(LXC_STATE_DIR, name, pid)) < 0) {
1877
                virReportSystemError(-rc,
1878 1879
                                     _("Unable to write pid file '%s/%s.pid'"),
                                     LXC_STATE_DIR, name);
1880 1881
                _exit(1);
            }
1882

1883 1884 1885 1886
            /* First child now exits, allowing original caller
             * (ie libvirtd's LXC driver to complete their
             * waitpid & continue */
            _exit(0);
1887 1888
        }

1889 1890
        /* Don't hold onto any cwd we inherit from libvirtd either */
        if (chdir("/") < 0) {
1891
            virReportSystemError(errno, "%s",
1892
                                 _("Unable to change to root dir"));
1893 1894 1895 1896
            goto cleanup;
        }

        if (setsid() < 0) {
1897
            virReportSystemError(errno, "%s",
1898
                                 _("Unable to become session leader"));
1899 1900 1901
            goto cleanup;
        }
    }
1902 1903

    /* Accept initial client which is the libvirtd daemon */
1904
    if ((client = accept(monitor, NULL, 0)) < 0) {
1905
        virReportSystemError(errno, "%s",
1906
                             _("Failed to accept a connection from driver"));
1907
        goto cleanup;
1908 1909
    }

1910
    rc = virLXCControllerRun(ctrl, securityDriver,
1911
                             monitor, client,
1912
                             ttyFDs, nttyFDs, handshakefd);
1913

1914
cleanup:
1915
    virPidFileDelete(LXC_STATE_DIR, name);
1916
    virLXCControllerDeleteInterfaces(ctrl);
J
Jim Meyering 已提交
1917 1918
    if (sockpath)
        unlink(sockpath);
1919
    VIR_FREE(sockpath);
1920
    virLXCControllerFree(ctrl);
1921

1922
    return rc ? EXIT_FAILURE : EXIT_SUCCESS;
1923
}