On Fri, Jun 17, 2011 at 01:38:21PM +0100, Daniel P. Berrange wrote:
> The current sanlock plugin requires a central management
> application to manually add <lease> elements to each guest,
> to protect resources that are assigned to it (eg writable
> disks). This makes the sanlock plugin useless for usage
> in more adhoc deployment environments where there is no
> central authority to associate disks with leases.
>
> This patch adds a mode where the sanlock plugin will
> automatically create leases for each assigned read-write
> disk, using a md5 checksum of the fully qualified disk
> path. This can work pretty well if guests are using
> stable disk paths for block devices eg /dev/disk/by-path/XXXX
> symlinks, or if all hosts have NFS volumes mounted in
> a consistent pattern.
>
> The plugin will create one lockspace for managing disks
> with filename /var/lib/libvirt/sanlock/__LIBVIRT__DISKS__.
> For each VM disks, there will be another file to hold
> a lease /var/lib/libvirt/sanlock/5903e5d25e087e60a20fe4566fab41fd
> Each VM disk lease is usually 1 MB in size. A nightly
> cron job will delete any unused lease files from the
> lockspace directory.
>
> To make use of this capability the admin will need todo
> several tasks:
>
> - Mount an NFS volume (or other shared filesystem)
> on /var/lib/libvirt/sanlock
> - Configure 'host_id' in /etc/libvirt/qemu-sanlock.conf
> with a unique value for each host with the same NFS
> mount
> - Toggle the 'auto_disk_leases' parameter in qemu-sanlock.conf
>
> Technically the first step can be skipped, in which case
> sanlock will only protect against 2 vms on the same host
> using the same disk (or the same VM being started twice
> due to error by libvirt).
>
> * src/locking/libvirt_sanlock.aug,
> src/locking/sanlock.conf,
> src/locking/test_libvirt_sanlock.aug: Add config params
> for configuring auto lease setup
> * libvirt.spec.in: Add virt-sanlock-cleanup program, man
> page and cronjob
> * tools/virt-sanlock-cleanup.cron.in: Nightly cron job
> * tools/virt-sanlock-cleanup.in: Script to purge unused
> disk resource lease files
> ---
> libvirt.spec.in | 3 +
> src/locking/libvirt_sanlock.aug | 6 +-
> src/locking/lock_driver_sanlock.c | 449 ++++++++++++++++++++++++++++++---
> src/locking/sanlock.conf | 60 +++++
> src/locking/test_libvirt_sanlock.aug | 10 +-
> tools/.gitignore | 3 +
> tools/Makefile.am | 25 ++-
> tools/virt-sanlock-cleanup.cron.in | 4 +
> tools/virt-sanlock-cleanup.in | 91 +++++++
> 9 files changed, 607 insertions(+), 44 deletions(-)
> create mode 100644 tools/virt-sanlock-cleanup.cron.in
> create mode 100644 tools/virt-sanlock-cleanup.in
>
> diff --git a/libvirt.spec.in b/libvirt.spec.in
> index a8d7026..8f26876 100644
> --- a/libvirt.spec.in
> +++ b/libvirt.spec.in
> @@ -1025,9 +1025,12 @@ fi
> %files lock-sanlock
> %defattr(-, root, root)
> %config(noreplace) %{_sysconfdir}/libvirt/qemu-sanlock.conf
> +%{_sysconfdir}/cron.daily/virt-sanlock-cleanup
> %attr(0755, root, root) %{_libdir}/libvirt/lock-driver/sanlock.so
> %{_datadir}/augeas/lenses/libvirt_sanlock.aug
> %{_datadir}/augeas/lenses/tests/test_libvirt_sanlock.aug
> +%{_sbindir}/virt-sanlock-cleanup
> +%{_mandir}/man8/virt-sanlock-cleanup.8*
> %endif
>
> %files client -f %{name}.lang
> diff --git a/src/locking/libvirt_sanlock.aug b/src/locking/libvirt_sanlock.aug
> index baa639a..548181e 100644
> --- a/src/locking/libvirt_sanlock.aug
> +++ b/src/locking/libvirt_sanlock.aug
> @@ -17,7 +17,11 @@ module Libvirt_sanlock =
>
>
> (* Each enty in the config is one of the following three ... *)
> - let entry = bool_entry "require_lease_for_disks"
> + let entry = str_entry "disk_lease_dir"
> + | bool_entry "auto_disk_leases"
> + | int_entry "max_hosts"
> + | int_entry "host_id"
> + | bool_entry "require_lease_for_disks"
> let comment = [ label "#comment" . del /#[ \t]*/ "# " . store /([^ \t\n][^\n]*)?/ . del /\n/ "\n" ]
> let empty = [ label "#empty" . eol ]
>
> diff --git a/src/locking/lock_driver_sanlock.c b/src/locking/lock_driver_sanlock.c
> index 7ad54e8..50fa9cc 100644
> --- a/src/locking/lock_driver_sanlock.c
> +++ b/src/locking/lock_driver_sanlock.c
> @@ -28,9 +28,13 @@
> #include <stdio.h>
> #include <errno.h>
> #include <sys/types.h>
> +#include <sys/stat.h>
> +#include <fcntl.h>
>
> #include <sanlock.h>
> #include <sanlock_resource.h>
> +#include <sanlock_direct.h>
> +#include <sanlock_admin.h>
>
> #include "lock_driver.h"
> #include "logging.h"
> @@ -38,6 +42,10 @@
> #include "memory.h"
> #include "util.h"
> #include "files.h"
> +#include "md5.h"
> +#include "conf.h"
> +
> +#include "configmake.h"
>
> #define VIR_FROM_THIS VIR_FROM_LOCKING
>
> @@ -46,6 +54,8 @@
> __FUNCTION__, __LINE__, __VA_ARGS__)
>
>
> +#define VIR_LOCK_MANAGER_SANLOCK_AUTO_DISK_LOCKSPACE "__LIBVIRT__DISKS__"
> +
> typedef struct _virLockManagerSanlockDriver virLockManagerSanlockDriver;
> typedef virLockManagerSanlockDriver *virLockManagerSanlockDriverPtr;
>
> @@ -54,6 +64,10 @@ typedef virLockManagerSanlockPrivate *virLockManagerSanlockPrivatePtr;
>
> struct _virLockManagerSanlockDriver {
> bool requireLeaseForDisks;
> + int hostID;
> + int maxHosts;
> + bool autoDiskLease;
> + char *autoDiskLeasePath;
> };
>
> static virLockManagerSanlockDriver *driver = NULL;
> @@ -98,16 +112,155 @@ static int virLockManagerSanlockLoadConfig(const char *configFile)
> return -1; \
> }
>
> + p = virConfGetValue(conf, "auto_disk_leases");
> + CHECK_TYPE("auto_disk_leases", VIR_CONF_LONG);
> + if (p) driver->autoDiskLease = p->l;
> +
> + p = virConfGetValue(conf, "disk_lease_dir");
> + CHECK_TYPE("disk_lease_dir", VIR_CONF_STRING);
> + if (p && p->str) {
> + VIR_FREE(driver->autoDiskLeasePath);
> + if (!(driver->autoDiskLeasePath = strdup(p->str))) {
> + virReportOOMError();
> + virConfFree(conf);
> + return -1;
> + }
> + }
> +
> + p = virConfGetValue(conf, "max_hosts");
> + CHECK_TYPE("max_hosts", VIR_CONF_LONG);
> + if (p) driver->maxHosts = p->l;
> +
> + p = virConfGetValue(conf, "host_id");
> + CHECK_TYPE("host_id", VIR_CONF_LONG);
> + if (p) driver->hostID = p->l;
> +
> p = virConfGetValue(conf, "require_lease_for_disks");
> CHECK_TYPE("require_lease_for_disks", VIR_CONF_LONG);
> if (p)
> driver->requireLeaseForDisks = p->l;
> + else
> + driver->requireLeaseForDisks = driver->autoDiskLease ? false : true;
>
> virConfFree(conf);
> return 0;
> }
Okay I got the answer w.r.t. the macro use in previous patch
> +static int virLockManagerSanlockSetupLockspace(void)
> +{
> + int fd = -1;
> + struct stat st;
> + int rv;
> + struct sanlk_lockspace ls;
> + char *path = NULL;
> +
> + if (virAsprintf(&path, "%s/%s",
> + driver->autoDiskLeasePath,
> + VIR_LOCK_MANAGER_SANLOCK_AUTO_DISK_LOCKSPACE) < 0) {
> + virReportOOMError();
> + goto error;
> + }
> +
> + memcpy(ls.name, VIR_LOCK_MANAGER_SANLOCK_AUTO_DISK_LOCKSPACE, SANLK_NAME_LEN);
> + ls.host_id = 0; /* Doesn't matter for initialization */
> + ls.flags = 0;
> + memcpy(&ls.host_id_disk, path, sizeof(struct sanlk_disk));
> + ls.host_id_disk.offset = 0;
> +
> + /* Stage 1: Ensure the lockspace file exists on disk, has
> + * space allocated for it and is initialized with lease
> + */
> + if (stat(path, &st) < 0) {
> + VIR_DEBUG("Lockspace %s does not yet exist", path);
> + if ((fd = open(path, O_WRONLY|O_CREAT|O_EXCL, 0600)) < 0) {
> + if (errno != EEXIST) {
> + virReportSystemError(errno,
> + _("Unable to create lockspace %s"),
> + path);
> + goto error;
> + }
> + VIR_DEBUG("Someone else just created lockspace %s", path);
> + } else {
> + if ((rv = sanlock_direct_align(&ls.host_id_disk)) < 0) {
> + if (rv <= -200)
> + virLockError(VIR_ERR_INTERNAL_ERROR,
> + _("Unable to query sector size %s: error %d"),
> + path, rv);
> + else
> + virReportSystemError(-rv,
> + _("Unable to query sector size %s"),
> + path);
> + goto error_unlink;
> + }
> +
> + /*
> + * Pre allocate enough data for 1 block of leases at preferred alignment
> + */
> + if (safezero(fd, 0, 0, rv) < 0) {
> + virReportSystemError(errno,
> + _("Unable to allocate lockspace %s"),
> + path);
> + goto error_unlink;
> + }
> +
> + if (VIR_CLOSE(fd) < 0) {
> + virReportSystemError(errno,
> + _("Unable to save lockspace %s"),
> + path);
> + goto error_unlink;
> + }
> +
> + if ((rv = sanlock_direct_init(&ls, NULL, 0, driver->maxHosts, 0)) < 0) {
> + if (rv <= -200)
> + virLockError(VIR_ERR_INTERNAL_ERROR,
> + _("Unable to initialize lockspace %s: error %d"),
> + path, rv);
> + else
> + virReportSystemError(-rv,
> + _("Unable to initialize lockspace %s"),
> + path);
> + goto error_unlink;
> + }
> + VIR_DEBUG("Lockspace %s has been initialized", path);
> + }
> + }
> +
> + ls.host_id = driver->hostID;
> + /* Stage 2: Try to register the lockspace with the daemon.
> + * If the lockspace is already registered, we should get EEXIST back
> + * in which case we can just carry on with life
> + */
> + if ((rv = sanlock_add_lockspace(&ls, 0)) < 0) {
> + if (-rv != EEXIST) {
> + if (rv <= -200)
> + virLockError(VIR_ERR_INTERNAL_ERROR,
> + _("Unable to add lockspace %s: error %d"),
> + path, rv);
> + else
> + virReportSystemError(-rv,
> + _("Unable to add lockspace %s"),
> + path);
> + return -1;
> + } else {
> + VIR_DEBUG("Lockspace %s is already registered", path);
> + }
> + } else {
> + VIR_DEBUG("Lockspace %s has been registered", path);
> + }
> +
> + return 0;
> +
> +error_unlink:
> + if (path)
> + unlink(path);
> +error:
> + VIR_FORCE_CLOSE(fd);
> + VIR_FREE(path);
> + return -1;
> +}
> +
>
> +static int virLockManagerSanlockDeinit(void);
> static int virLockManagerSanlockInit(unsigned int version,
> const char *configFile,
> unsigned int flags)
> @@ -124,11 +277,32 @@ static int virLockManagerSanlockInit(unsigned int version,
> }
>
> driver->requireLeaseForDisks = true;
> + driver->hostID = 0;
> + driver->maxHosts = 64;
> + driver->autoDiskLease = false;
> + if (!(driver->autoDiskLeasePath = strdup(LOCALSTATEDIR "/lib/libvirt/sanlock"))) {
> + VIR_FREE(driver);
> + virReportOOMError();
> + goto error;
> + }
>
> if (virLockManagerSanlockLoadConfig(configFile) < 0)
> - return -1;
> + goto error;
> +
> + if (driver->autoDiskLease && !driver->hostID) {
> + virLockError(VIR_ERR_INTERNAL_ERROR,
> + _("Automatic disk lease mode enabled, but no host ID is set"));
> + goto error;
> + }
> +
> + if (virLockManagerSanlockSetupLockspace() < 0)
> + goto error;
>
> return 0;
> +
> +error:
> + virLockManagerSanlockDeinit();
> + return -1;
> }
>
> static int virLockManagerSanlockDeinit(void)
> @@ -136,9 +310,10 @@ static int virLockManagerSanlockDeinit(void)
> if (!driver)
> return 0;
>
> - virLockError(VIR_ERR_INTERNAL_ERROR, "%s",
> - _("Unloading sanlock plugin is forbidden"));
> - return -1;
> + VIR_FREE(driver->autoDiskLeasePath);
> + VIR_FREE(driver);
> +
> + return 0;
> }
>
>
> @@ -214,51 +389,50 @@ static void virLockManagerSanlockFree(virLockManagerPtr lock)
> lock->privateData = NULL;
> }
>
> -static int virLockManagerSanlockAddResource(virLockManagerPtr lock,
> - unsigned int type,
> - const char *name,
> - size_t nparams,
> - virLockManagerParamPtr params,
> - unsigned int flags)
> +
> +static const char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7',
> + '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
> +
> +static int virLockManagerSanlockDiskLeaseName(const char *path,
> + char *str,
> + size_t strbuflen)
> {
> - virLockManagerSanlockPrivatePtr priv = lock->privateData;
> - struct sanlk_resource *res;
> + unsigned char buf[MD5_DIGEST_SIZE];
> int i;
>
> - virCheckFlags(VIR_LOCK_MANAGER_RESOURCE_READONLY |
> - VIR_LOCK_MANAGER_RESOURCE_SHARED, -1);
> -
> - if (priv->res_count == SANLK_MAX_RESOURCES) {
> + if (strbuflen < ((MD5_DIGEST_SIZE * 2) + 1)) {
> virLockError(VIR_ERR_INTERNAL_ERROR,
> - _("Too many resources %d for object"),
> - SANLK_MAX_RESOURCES);
> + _("String length too small to store md5 checksum"));
> return -1;
> }
>
> - if (type == VIR_LOCK_MANAGER_RESOURCE_TYPE_DISK) {
> - if (!(flags & (VIR_LOCK_MANAGER_RESOURCE_SHARED |
> - VIR_LOCK_MANAGER_RESOURCE_READONLY)))
> - priv->hasRWDisks = true;
> - return 0;
> - }
> -
> - if (type != VIR_LOCK_MANAGER_RESOURCE_TYPE_LEASE)
> - return 0;
> -
> - if (flags & VIR_LOCK_MANAGER_RESOURCE_READONLY) {
> - virLockError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
> - _("Readonly leases are not supported"));
> + if (!(md5_buffer(path, strlen(path), buf))) {
> + virLockError(VIR_ERR_INTERNAL_ERROR,
> + _("Unable to compute md5 checksum"));
> return -1;
> }
> - if (flags & VIR_LOCK_MANAGER_RESOURCE_SHARED) {
> - virLockError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
> - _("Sharable leases are not supported"));
> - return -1;
> +
> + for (i = 0 ; i < MD5_DIGEST_SIZE ; i++) {
> + str[i*2] = hex[(buf[i] >> 4) & 0xf];
> + str[(i*2)+1] = hex[buf[i] & 0xf];
> }
> + str[(MD5_DIGEST_SIZE*2)+1] = '\0';
> + return 0;
> +}
> +
> +static int virLockManagerSanlockAddLease(virLockManagerPtr lock,
> + const char *name,
> + size_t nparams,
> + virLockManagerParamPtr params)
> +{
> + virLockManagerSanlockPrivatePtr priv = lock->privateData;
> + int ret = -1;
> + struct sanlk_resource *res = NULL;
> + int i;
>
> if (VIR_ALLOC_VAR(res, struct sanlk_disk, 1) < 0) {
> virReportOOMError();
> - return -1;
> + goto cleanup;
> }
>
> res->num_disks = 1;
> @@ -266,7 +440,7 @@ static int virLockManagerSanlockAddResource(virLockManagerPtr lock,
> virLockError(VIR_ERR_INTERNAL_ERROR,
> _("Resource name '%s' exceeds %d characters"),
> name, SANLK_NAME_LEN);
> - goto error;
> + goto cleanup;
> }
>
> for (i = 0; i < nparams; i++) {
> @@ -275,7 +449,7 @@ static int virLockManagerSanlockAddResource(virLockManagerPtr lock,
> virLockError(VIR_ERR_INTERNAL_ERROR,
> _("Lease path '%s' exceeds %d characters"),
> params[i].value.str, SANLK_PATH_LEN);
> - goto error;
> + goto cleanup;
> }
> } else if (STREQ(params[i].key, "offset")) {
> res->disks[0].offset = params[i].value.ul;
> @@ -284,20 +458,213 @@ static int virLockManagerSanlockAddResource(virLockManagerPtr lock,
> virLockError(VIR_ERR_INTERNAL_ERROR,
> _("Resource lockspace '%s' exceeds %d characters"),
> params[i].value.str, SANLK_NAME_LEN);
> - goto error;
> + goto cleanup;
> }
> }
> }
>
> priv->res_args[priv->res_count] = res;
> priv->res_count++;
> +
> + ret = 0;
> +
> +cleanup:
> + if (ret == -1)
> + VIR_FREE(res);
> + return ret;
> +}
> +
> +
> +
> +
> +static int virLockManagerSanlockAddDisk(virLockManagerPtr lock,
> + const char *name,
> + size_t nparams,
> + virLockManagerParamPtr params ATTRIBUTE_UNUSED)
> +{
> + virLockManagerSanlockPrivatePtr priv = lock->privateData;
> + int ret = -1;
> + struct sanlk_resource *res = NULL;
> + char *path = NULL;
> +
> + if (nparams) {
> + virLockError(VIR_ERR_INTERNAL_ERROR,
> + _("Unexpected lock parameters for disk resource"));
> + return -1;
> + }
> +
> + if (VIR_ALLOC_VAR(res, struct sanlk_disk, 1) < 0) {
> + virReportOOMError();
> + goto cleanup;
> + }
> +
> + res->num_disks = 1;
> + if (virLockManagerSanlockDiskLeaseName(name, res->name, SANLK_NAME_LEN) < 0)
> + goto cleanup;
> +
> + if (virAsprintf(&path, "%s/%s",
> + driver->autoDiskLeasePath, res->name) < 0) {
> + virReportOOMError();
> + goto cleanup;
> + }
> + if (!virStrcpy(res->disks[0].path, path, SANLK_PATH_LEN)) {
> + virLockError(VIR_ERR_INTERNAL_ERROR,
> + _("Lease path '%s' exceeds %d characters"),
> + path, SANLK_PATH_LEN);
> + goto cleanup;
> + }
> +
> + if (!virStrcpy(res->lockspace_name,
> + VIR_LOCK_MANAGER_SANLOCK_AUTO_DISK_LOCKSPACE,
> + SANLK_NAME_LEN)) {
> + virLockError(VIR_ERR_INTERNAL_ERROR,
> + _("Resource lockspace '%s' exceeds %d characters"),
> + VIR_LOCK_MANAGER_SANLOCK_AUTO_DISK_LOCKSPACE, SANLK_NAME_LEN);
> + goto cleanup;
> + }
> +
> + priv->res_args[priv->res_count] = res;
> + priv->res_count++;
> +
> + ret = 0;
> +
> +cleanup:
> + if (ret == -1)
> + VIR_FREE(res);
> + VIR_FREE(path);
> + return ret;
> +}
> +
> +
> +static int virLockManagerSanlockCreateLease(struct sanlk_resource *res)
> +{
> + int fd = -1;
> + struct stat st;
> + int rv;
> +
> + if (stat(res->disks[0].path, &st) < 0) {
> + VIR_DEBUG("Lockspace %s does not yet exist", res->disks[0].path);
> + if ((fd = open(res->disks[0].path, O_WRONLY|O_CREAT|O_EXCL, 0600)) < 0) {
> + if (errno != EEXIST) {
> + virReportSystemError(errno,
> + _("Unable to create lockspace %s"),
> + res->disks[0].path);
> + return -1;
> + }
> + VIR_DEBUG("Someone else just created lockspace %s", res->disks[0].path);
> + } else {
> + if ((rv = sanlock_direct_align(&res->disks[0])) < 0) {
> + if (rv <= -200)
> + virLockError(VIR_ERR_INTERNAL_ERROR,
> + _("Unable to query sector size %s: error %d"),
> + res->disks[0].path, rv);
> + else
> + virReportSystemError(-rv,
> + _("Unable to query sector size %s"),
> + res->disks[0].path);
> + goto error_unlink;
> + }
> +
> + /*
> + * Pre allocate enough data for 1 block of leases at preferred alignment
> + */
> + if (safezero(fd, 0, 0, rv) < 0) {
> + virReportSystemError(errno,
> + _("Unable to allocate lease %s"),
> + res->disks[0].path);
> + goto error_unlink;
> + }
> +
> + if (VIR_CLOSE(fd) < 0) {
> + virReportSystemError(errno,
> + _("Unable to save lease %s"),
> + res->disks[0].path);
> + goto error_unlink;
> + }
> +
> + if ((rv = sanlock_direct_init(NULL, res, driver->maxHosts, driver->maxHosts, 0)) < 0) {
> + if (rv <= -200)
> + virLockError(VIR_ERR_INTERNAL_ERROR,
> + _("Unable to initialize lease %s: error %d"),
> + res->disks[0].path, rv);
> + else
> + virReportSystemError(-rv,
> + _("Unable to initialize lease %s"),
> + res->disks[0].path);
> + goto error_unlink;
> + }
> + VIR_DEBUG("Lease %s has been initialized", res->disks[0].path);
> + }
> + }
> +
> return 0;
>
> -error:
> - VIR_FREE(res);
> +error_unlink:
> + unlink(res->disks[0].path);
> + VIR_FORCE_CLOSE(fd);
> return -1;
> }
>
> +
> +static int virLockManagerSanlockAddResource(virLockManagerPtr lock,
> + unsigned int type,
> + const char *name,
> + size_t nparams,
> + virLockManagerParamPtr params,
> + unsigned int flags)
> +{
> + virLockManagerSanlockPrivatePtr priv = lock->privateData;
> +
> + virCheckFlags(VIR_LOCK_MANAGER_RESOURCE_READONLY |
> + VIR_LOCK_MANAGER_RESOURCE_SHARED, -1);
> +
> + if (priv->res_count == SANLK_MAX_RESOURCES) {
> + virLockError(VIR_ERR_INTERNAL_ERROR,
> + _("Too many resources %d for object"),
> + SANLK_MAX_RESOURCES);
> + return -1;
> + }
> +
> + if (flags & VIR_LOCK_MANAGER_RESOURCE_READONLY) {
> + virLockError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
> + _("Readonly leases are not supported"));
> + return -1;
> + }
> + if (flags & VIR_LOCK_MANAGER_RESOURCE_SHARED) {
> + virLockError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
> + _("Sharable leases are not supported"));
> + return -1;
> + }
> +
> + switch (type) {
> + case VIR_LOCK_MANAGER_RESOURCE_TYPE_DISK:
> + if (driver->autoDiskLease) {
> + if (virLockManagerSanlockAddDisk(lock, name, nparams, params) < 0)
> + return -1;
> +
> + if (virLockManagerSanlockCreateLease(priv->res_args[priv->res_count-1]) < 0)
> + return -1;
> + } else {
> + if (!(flags & (VIR_LOCK_MANAGER_RESOURCE_SHARED |
> + VIR_LOCK_MANAGER_RESOURCE_READONLY)))
> + priv->hasRWDisks = true;
> + /* Ignore disk resources without error */
> + }
> + break;
> +
> + case VIR_LOCK_MANAGER_RESOURCE_TYPE_LEASE:
> + if (virLockManagerSanlockAddLease(lock, name, nparams, params) < 0)
> + return -1;
> + break;
> +
> + default:
> + /* Ignore other resources, without error */
> + break;
> + }
> +
> + return 0;
> +}
> +
> static int virLockManagerSanlockAcquire(virLockManagerPtr lock,
> const char *state,
> unsigned int flags)
> diff --git a/src/locking/sanlock.conf b/src/locking/sanlock.conf
> index 818b529..fb04ea6 100644
> --- a/src/locking/sanlock.conf
> +++ b/src/locking/sanlock.conf
> @@ -1,6 +1,66 @@
> +
> +#
> +# The default sanlock configuration requires the management
> +# application to manually define <lease> elements in the
> +# guest configuration, typically one lease per disk. An
> +# alternative is to enable "auto disk lease" mode. In this
> +# usage, libvirt will automatically create a lockspace and
> +# lease for each fully qualified disk path. This works if
> +# you are able to ensure stable, unique disk paths across
> +# all hosts in a network.
> +#
> +# Uncomment this to enable automatic lease creation.
> +#
> +# NB: the 'host_id' parameter must be set if enabling this
> +#
> +#auto_disk_leases = 1
> +
> +#
> +# The default location in which lockspaces are created when
> +# automatic lease creation is enabled. For each unique disk
> +# path, a file $LEASE_DIR/NNNNNNNNNNNNNN will be created
> +# where 'NNNNNNNNNNNN' is the MD5 checkout of the disk path.
> +#
> +# If this directory is on local storage, it will only protect
> +# against a VM being started twice on the same host, or two
> +# guests on the same host using the same disk path. If the
> +# directory is on NFS, then it can protect against concurrent
> +# usage across all hosts which have the share mounted.
> +#
> +# Recommendation is to just mount this default location as
> +# an NFS volume. Uncomment this, if you would prefer the mount
> +# point to be somewhere else.
> +#
> +#disk_lease_dir = "/var/lib/libvirt/sanlock"
> +
> +#
> +# When automatically creating leases for disks, each host which
> +# can access the filesystem mounted at 'disk_lease_dir' will need
> +# to have a unique host ID assigned. The 'max_hosts' parameter
> +# specifies an upper limit on the number of participating hosts.
> +#
> +# Each additional host requires 1 sector of disk space, usually
> +# 512 bytes. The default is 64, and can be reduced if you don't
> +# have many hosts, or increased if you have more.
> +#
> +#max_hosts = 64
> +
> +#
> +# The unique ID for this host.
> +#
> +# IMPORTANT: *EVERY* host which can access the filesystem mounted
> +# at 'disk_lease_dir' *MUST* be given a different host ID.
> +#
> +# This parameter has no default and must be manually set if
> +# 'auto_disk_leases' is enabled
> +#host_id = 1
> +
> #
> # Flag to determine whether we allow starting of guests
> # which do not have any <lease> elements defined in their
> # configuration.
> #
> +# If 'auto_disk_leases' is disabled, this setting defaults
> +# to enabled, otherwise it defaults to disabled.
> +#
> #require_lease_for_disks = 1
> diff --git a/src/locking/test_libvirt_sanlock.aug b/src/locking/test_libvirt_sanlock.aug
> index 2f1f57a..26a0608 100644
> --- a/src/locking/test_libvirt_sanlock.aug
> +++ b/src/locking/test_libvirt_sanlock.aug
> @@ -1,7 +1,15 @@
> module Test_libvirt_sanlock =
>
> - let conf = "require_lease_for_disks = 1
> + let conf = "auto_disk_leases = 1
> +disk_lease_dir = \"/var/lib/libvirt/sanlock\"
> +max_hosts = 64
> +host_id = 1
> +require_lease_for_disks = 1
> "
>
> test Libvirt_sanlock.lns get conf =
> +{ "auto_disk_leases" = "1" }
> +{ "disk_lease_dir" = "/var/lib/libvirt/sanlock" }
> +{ "max_hosts" = "64" }
> +{ "host_id" = "1" }
> { "require_lease_for_disks" = "1" }
> diff --git a/tools/.gitignore b/tools/.gitignore
> index 3e34ea8..a92735d 100644
> --- a/tools/.gitignore
> +++ b/tools/.gitignore
> @@ -1,7 +1,10 @@
> libvirt-guests.init
> virt-xml-validate
> virt-pki-validate
> +virt-sanlock-cleanup
> +virt-sanlock-cleanup.cron
> *.1
> +*.8
> Makefile
> Makefile.in
> virsh-net-edit.c
> diff --git a/tools/Makefile.am b/tools/Makefile.am
> index 826674a..81e758e 100644
> --- a/tools/Makefile.am
> +++ b/tools/Makefile.am
> @@ -12,6 +12,8 @@ EXTRA_DIST = \
> $(ICON_FILES) \
> virt-xml-validate.in \
> virt-pki-validate.in \
> + virt-sanlock-cleanup.in \
> + virt-sanlock-cleanup.cron.in \
> virsh.pod \
> libvirt-guests.init.sh \
> libvirt-guests.sysconf
> @@ -19,8 +21,17 @@ EXTRA_DIST = \
> bin_SCRIPTS = virt-xml-validate virt-pki-validate
> bin_PROGRAMS = virsh
>
> -dist_man1_MANS = virt-xml-validate.1 virt-pki-validate.1 virsh.1
> +if HAVE_SANLOCK
> +sbin_SCRIPTS = virt-sanlock-cleanup
> +
> +crondir = $(sysconfdir)/cron.daily
> +cron_DATA = virt-sanlock-cleanup.cron
> +endif
>
> +dist_man1_MANS = virt-xml-validate.1 virt-pki-validate.1 virsh.1
> +if HAVE_SANLOCK
> +dist_man8_MANS = virt-sanlock-cleanup.8
> +endif
>
> virt-xml-validate: virt-xml-validate.in Makefile
> $(AM_V_GEN)sed -e 's,@SCHEMADIR@,$(pkgdatadir)/schemas,' < $< > $@ \
> @@ -36,6 +47,18 @@ virt-pki-validate: virt-pki-validate.in Makefile
> virt-pki-validate.1: virt-pki-validate.in
> $(AM_V_GEN)$(POD2MAN) $< $(srcdir)/$@
>
> +virt-sanlock-cleanup: virt-sanlock-cleanup.in Makefile
> + $(AM_V_GEN)sed -e 's,@SYSCONFDIR@,$(sysconfdir),' \
> + -e 's,@LOCALSTATEDIR@,$(localstatedir),' < $< > $@ \
> + || (rm $@ && exit 1) && chmod +x $@
> +
> +virt-sanlock-cleanup.cron: virt-sanlock-cleanup.cron.in Makefile
> + $(AM_V_GEN)sed -e 's,@SBINDIR@,$(sbindir),' < $< > $@ \
> + || (rm $@ && exit 1) && chmod +x $@
> +
> +virt-sanlock-cleanup.8: virt-sanlock-cleanup.in
> + $(AM_V_GEN)$(POD2MAN) $< $(srcdir)/$@
> +
> virsh_SOURCES = \
> console.c console.h \
> virsh.c
> diff --git a/tools/virt-sanlock-cleanup.cron.in b/tools/virt-sanlock-cleanup.cron.in
> new file mode 100644
> index 0000000..14a1773
> --- /dev/null
> +++ b/tools/virt-sanlock-cleanup.cron.in
> @@ -0,0 +1,4 @@
> +#!/bin/sh
> +
> +@SBINDIR@/virt-sanlock-cleanup -q
> +exit 0
> diff --git a/tools/virt-sanlock-cleanup.in b/tools/virt-sanlock-cleanup.in
> new file mode 100644
> index 0000000..483b595
> --- /dev/null
> +++ b/tools/virt-sanlock-cleanup.in
> @@ -0,0 +1,91 @@
> +#!/bin/sh
> +
> +# A script to cleanup resource leases auto-created by
> +# the libvirt lock plugin for sanlock
> +
> +verbose=1
> +if test "$1" = "-q" ; then
> + verbose=0
> +fi
> +
> +LOCKSPACE="__LIBVIRT__DISKS__"
> +
> +LOCKDIR=`augtool print /files@SYSCONFDIR@/libvirt/qemu-sanlock.conf/disk_lease_dir`
> +if test $? != 0 -o "x$DIR" = "x" ; then
> + LOCKDIR="@LOCALSTATEDIR@/lib/libvirt/sanlock"
> +fi
> +
> +function notify() {
> + if test $verbose = 1 ; then
> + echo "$@"
> + fi
> +}
> +
> +cd $LOCKDIR
> +
> +for MD5 in *
> +do
> + if test $MD5 != '*' -a $MD5 != $LOCKSPACE ; then
> + RESOURCE="$LOCKSPACE:$MD5:$LOCKDIR/$MD5:0"
> + notify -n "Cleanup: $RESOURCE "
> + sanlock client command -r $RESOURCE -c /bin/rm -f "$LOCKDIR/$MD5" 2>/dev/null
> + if test $? = 0 ; then
> + notify "PASS"
> + else
> + notify "FAIL"
> + fi
> + fi
> +done
> +
> +exit 0
> +
> +: <<=cut
> +=pod
> +
> +=head1 NAME
> +
> + virt-sanlock-cleanup - remove stale sanlock resource lease files
> +
> +=head1 SYNOPSIS
> +
> + virt-sanlock-cleanup
> +
> +=head1 DESCRIPTION
> +
> +This tool removes any resource lease files created by the sanlock
> +lock manager plugin. The resource lease files only need to exist
> +on disks when a guest using the resource is active. This script
> +reclaims the disk space used by resources which are not currently
> +active.
> +
> +=head1 EXIT STATUS
> +
> +Upon successful cleanup, an exit status of 0 will be set. Upon
> +failure a non-zero status will be set.
> +
> +=head1 AUTHOR
> +
> +Daniel Berrange
> +
> +=head1 BUGS
> +
> +Report any bugs discovered to the libvirt community via the
> +mailing list C<http://libvirt.org/contact.html> or bug tracker C<http://libvirt.org/bugs.html>.
> +Alternatively report bugs to your software distributor / vendor.
> +
> +=head1 COPYRIGHT
> +
> +Copyright (C) 2011 Red Hat, Inc.
> +
> +=head1 LICENSE
> +
> +virt-sanlock-cleanup is distributed under the terms of the GNU GPL v2+.
> +This is free software; see the source for copying conditions. There
> +is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR
> +PURPOSE
> +
> +=head1 SEE ALSO
> +
> +C<virsh(1)>, online instructions C<http://libvirt.org/locksanlock.html>
> +
> +=cut
ACK, let's push this that allows most users to benefits from the
locking if they don't have a preexisting infrastructure,
Daniel
--
Daniel Veillard | libxml Gnome XML XSLT toolkit http://xmlsoft.org/
daniel@xxxxxxxxxxxx | Rpmfind RPM search engine http://rpmfind.net/
http://veillard.com/ | virtualization library http://libvirt.org/
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