Added iSCSI storage pool backend

ChangeLog

@@ -1,3 +1,12 @@
+Wed Feb 20 10:44:27 EST 2008 Daniel P. Berrange <berrange@redhat.com>
+
+	* configure.in: Added check for iscsiadm tool
+	* libvirt.spec.in: Added dep on iscsi-initiator-utils
+	* po/POTFILES.in: Added storage_backend_iscsi.c
+	* src/Makefile.am, src/storage_backend.c,
+	src/storage_backend_iscsi.c, src/storage_backend_iscsi.h:
+	Added iSCSI storage pool backend
+
 Wed Feb 20 10:42:27 EST 2008 Daniel P. Berrange <berrange@redhat.com>
 
 	* qemud/qemud.c: Set close-on-exec flag for signal pipe

configure.in

@@ -561,6 +561,8 @@ AC_ARG_WITH(storage-fs,
 [  --with-storage-fs           with FileSystem backend for the storage driver (on)],[],[with_storage_fs=check])
 AC_ARG_WITH(storage-lvm,
 [  --with-storage-lvm          with LVM backend for the storage driver (on)],[],[with_storage_lvm=check])
+AC_ARG_WITH(storage-iscsi,
+[  --with-storage-iscsi        with iSCSI backend for the storage driver (on)],[],[with_storage_iscsi=check])
 
 if test "$with_storage_fs" = "yes" -o "$with_storage_fs" = "check"; then
   AC_PATH_PROG(MOUNT, [mount], [], [$PATH:/sbin:/usr/sbin])
@@ -655,6 +657,25 @@ fi
 AM_CONDITIONAL(WITH_STORAGE_LVM, [test "$with_storage_lvm" = "yes"])
 
 
+
+if test "$with_storage_iscsi" = "yes" -o "$with_storage_iscsi" = "check"; then
+  AC_PATH_PROG(ISCSIADM, [iscsiadm], [], [$PATH:/sbin:/usr/sbin])
+  if test "$with_storage_iscsi" = "yes" ; then
+    if test -z "$ISCSIADM" ; then AC_MSG_ERROR(We need iscsiadm for iSCSI storage driver) ; fi
+  else
+    if test -z "$ISCSIADM" ; then with_storage_iscsi=no ; fi
+
+    if test "$with_storage_iscsi" = "check" ; then with_storage_iscsi=yes ; fi
+  fi
+
+  if test "$with_storage_iscsi" = "yes" ; then
+    AC_DEFINE_UNQUOTED(WITH_STORAGE_ISCSI, 1, [whether iSCSI backend for storage driver is enabled])
+    AC_DEFINE_UNQUOTED([ISCSIADM],["$ISCSIADM"],[Location of iscsiadm program])
+  fi
+fi
+AM_CONDITIONAL(WITH_STORAGE_ISCSI, [test "$with_storage_iscsi" = "yes"])
+
+
 dnl
 dnl check for python
 dnl
@@ -869,6 +890,7 @@ AC_MSG_NOTICE([     Dir: yes])
 AC_MSG_NOTICE([      FS: $with_storage_fs])
 AC_MSG_NOTICE([   NetFS: $with_storage_fs])
 AC_MSG_NOTICE([     LVM: $with_storage_lvm])
+AC_MSG_NOTICE([   iSCSI: $with_storage_iscsi])
 AC_MSG_NOTICE([])
 AC_MSG_NOTICE([Libraries])
 AC_MSG_NOTICE([])

libvirt.spec.in

@@ -51,6 +51,8 @@ Requires: /usr/sbin/qcow-create
 %endif
 # For LVM drivers
 Requires: lvm2
+# For ISCSI driver
+Requires: iscsi-initiator-utils
 BuildRequires: xen-devel
 BuildRequires: libxml2-devel
 BuildRequires: readline-devel
@@ -77,6 +79,8 @@ BuildRequires: /usr/sbin/qcow-create
 %endif
 # For LVM drivers
 BuildRequires: lvm2
+# For ISCSI driver
+BuildRequires: iscsi-initiator-utils
 Obsoletes: libvir
 ExclusiveArch: i386 x86_64 ia64
 

po/POTFILES.in

@@ -13,6 +13,7 @@ src/remote_internal.c
 src/storage_backend.c
 src/storage_backend_fs.c
 src/storage_backend_logical.c
+src/storage_backend_iscsi.c
 src/storage_conf.c
 src/storage_driver.c
 src/sexpr.c

src/Makefile.am

@@ -74,6 +74,12 @@ else
 EXTRA_DIST += storage_backend_logical.h storage_backend_logical.c
 endif
 
+if WITH_STORAGE_ISCSI
+CLIENT_SOURCES +=  storage_backend_iscsi.h storage_backend_iscsi.c
+else
+EXTRA_DIST +=  storage_backend_iscsi.h storage_backend_iscsi.c
+endif
+
 
 
 libvirt_la_SOURCES = $(CLIENT_SOURCES) $(SERVER_SOURCES)

src/storage_backend.c

@@ -39,6 +39,10 @@
 #if WITH_STORAGE_LVM
 #include "storage_backend_logical.h"
 #endif
+#if WITH_STORAGE_ISCSI
+#include "storage_backend_iscsi.h"
+#endif
+
 
 #include "util.h"
 
@@ -54,6 +58,9 @@ static virStorageBackendPtr backends[] = {
 #if WITH_STORAGE_LVM
     &virStorageBackendLogical,
 #endif
+#if WITH_STORAGE_ISCSI
+    &virStorageBackendISCSI,
+#endif
 };
 
 
@@ -100,6 +107,10 @@ virStorageBackendFromString(const char *type) {
     if (STREQ(type, "logical"))
         return VIR_STORAGE_POOL_LOGICAL;
 #endif
+#if WITH_STORAGE_ISCSI
+    if (STREQ(type, "iscsi"))
+        return VIR_STORAGE_POOL_ISCSI;
+#endif
 
     virStorageReportError(NULL, VIR_ERR_INTERNAL_ERROR,
                           _("unknown storage backend type %s"), type);
@@ -120,6 +131,10 @@ virStorageBackendToString(int type) {
 #if WITH_STORAGE_LVM
     case VIR_STORAGE_POOL_LOGICAL:
         return "logical";
+#endif
+#if WITH_STORAGE_ISCSI
+    case VIR_STORAGE_POOL_ISCSI:
+        return "iscsi";
 #endif
     }
 

src/storage_backend_iscsi.c

@@ -0,0 +1,455 @@
+/*
+ * storage_backend_iscsi.c: storage backend for iSCSI handling
+ *
+ * Copyright (C) 2007-2008 Red Hat, Inc.
+ * Copyright (C) 2007-2008 Daniel P. Berrange
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA
+ *
+ * Author: Daniel P. Berrange <berrange@redhat.com>
+ */
+
+#include <config.h>
+
+#include <sys/socket.h>
+#include <netdb.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <string.h>
+#include <stdio.h>
+#include <regex.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <dirent.h>
+
+#include "storage_backend_iscsi.h"
+#include "util.h"
+
+static int
+virStorageBackendISCSITargetIP(virConnectPtr conn,
+                               const char *hostname,
+                               char *ipaddr,
+                               size_t ipaddrlen)
+{
+    struct addrinfo hints;
+    struct addrinfo *result = NULL;
+    int ret;
+
+    memset(&hints, 0, sizeof hints);
+    hints.ai_flags = AI_ADDRCONFIG;
+    hints.ai_family = AF_INET;
+    hints.ai_socktype = SOCK_STREAM;
+    hints.ai_protocol = 0;
+
+    ret = getaddrinfo(hostname, NULL, &hints, &result);
+    if (ret != 0) {
+        virStorageReportError(conn, VIR_ERR_INTERNAL_ERROR,
+                              _("host lookup failed %s"),
+                              gai_strerror(ret));
+        return -1;
+    }
+
+    if (result == NULL) {
+        virStorageReportError(conn, VIR_ERR_INTERNAL_ERROR,
+                              _("no IP address for target %s"),
+                              hostname);
+        return -1;
+    }
+
+    if (getnameinfo(result->ai_addr, result->ai_addrlen,
+                    ipaddr, ipaddrlen, NULL, 0,
+                    NI_NUMERICHOST) < 0) {
+        virStorageReportError(conn, VIR_ERR_INTERNAL_ERROR,
+                              _("cannot format ip addr for %s"),
+                              hostname);
+        freeaddrinfo(result);
+        return -1;
+    }
+
+    freeaddrinfo(result);
+    return 0;
+}
+
+static int
+virStorageBackendISCSIExtractSession(virConnectPtr conn,
+                                     virStoragePoolObjPtr pool,
+                                     char **const groups,
+                                     void *data)
+{
+    char **session = data;
+
+    if (STREQ(groups[1], pool->def->source.devices[0].path)) {
+        if ((*session = strdup(groups[0])) == NULL) {
+            virStorageReportError(conn, VIR_ERR_NO_MEMORY, _("session"));
+            return -1;
+        }
+    }
+
+    return 0;
+}
+
+static char *
+virStorageBackendISCSISession(virConnectPtr conn,
+                              virStoragePoolObjPtr pool)
+{
+    /*
+     * # iscsiadm --mode session  -P 0
+     * tcp: [1] 192.168.122.170:3260,1 demo-tgt-b
+     * tcp: [2] 192.168.122.170:3260,1 demo-tgt-a
+     *
+     * Pull out 2nd and 4th fields
+     */
+    const char *regexes[] = {
+        "^tcp:\\s+\\[(\\S+)\\]\\s+\\S+\\s+(\\S+)\\s*$"
+    };
+    int vars[] = {
+        2,
+    };
+    const char *prog[] = {
+        ISCSIADM, "--mode", "session", "-P", "0", NULL
+    };
+    char *session = NULL;
+
+    if (virStorageBackendRunProgRegex(conn, pool,
+                                      prog,
+                                      1,
+                                      regexes,
+                                      vars,
+                                      virStorageBackendISCSIExtractSession,
+                                      &session) < 0)
+        return NULL;
+
+    if (session == NULL) {
+        virStorageReportError(conn, VIR_ERR_INTERNAL_ERROR,
+                              _("cannot find session"));
+        return NULL;
+    }
+
+    return session;
+}
+
+static int
+virStorageBackendISCSIConnection(virConnectPtr conn,
+                                 virStoragePoolObjPtr pool,
+                                 const char *portal,
+                                 const char *action)
+{
+    const char *cmdargv[] = {
+        ISCSIADM, "--mode", "node", "--portal", portal,
+        "--targetname", pool->def->source.devices[0].path, action, NULL
+    };
+
+    if (virRun(conn, (char **)cmdargv, NULL) < 0)
+        return -1;
+
+    return 0;
+}
+
+
+static int
+virStorageBackendISCSIMakeLUN(virConnectPtr conn,
+                              virStoragePoolObjPtr pool,
+                              char **const groups,
+                              void *data ATTRIBUTE_UNUSED)
+{
+    virStorageVolDefPtr vol;
+    int fd = -1;
+    char lunid[100];
+    char *dev = groups[4];
+    int opentries = 0;
+    char *devpath = NULL;
+
+    snprintf(lunid, sizeof(lunid)-1, "lun-%s", groups[3]);
+
+    if ((vol = calloc(1, sizeof(virStorageVolDef))) == NULL) {
+        virStorageReportError(conn, VIR_ERR_NO_MEMORY, _("volume"));
+        return -1;
+    }
+
+    if ((vol->name = strdup(lunid)) == NULL) {
+        virStorageReportError(conn, VIR_ERR_NO_MEMORY, _("name"));
+        goto cleanup;
+    }
+
+    if ((devpath = malloc(5 + strlen(dev) + 1)) == NULL) {
+        virStorageReportError(conn, VIR_ERR_NO_MEMORY, _("devpath"));
+        goto cleanup;
+    }
+    strcpy(devpath, "/dev/");
+    strcat(devpath, dev);
+    /* It can take a little while between logging into the ISCSI
+     * server and udev creating the /dev nodes, so if we get ENOENT
+     * we must retry a few times - they should eventually appear.
+     * We currently wait for upto 5 seconds. Is this good enough ?
+     * Perhaps not on a very heavily loaded system Any other
+     * options... ?
+     */
+ reopen:
+    if ((fd = open(devpath, O_RDONLY)) < 0) {
+        opentries++;
+        if (errno == ENOENT && opentries < 50) {
+            usleep(100 * 1000);
+            goto reopen;
+        }
+        virStorageReportError(conn, VIR_ERR_INTERNAL_ERROR,
+                              _("cannot open %s: %s"),
+                              devpath, strerror(errno));
+        goto cleanup;
+    }
+
+    /* Now figure out the stable path
+     *
+     * XXX this method is O(N) because it scans the pool target
+     * dir every time its run. Should figure out a more efficient
+     * way of doing this...
+     */
+    if ((vol->target.path = virStorageBackendStablePath(conn,
+                                                        pool,
+                                                        devpath)) == NULL)
+        goto cleanup;
+
+    if (devpath != vol->target.path)
+        free(devpath);
+    devpath = NULL;
+
+    if (virStorageBackendUpdateVolInfoFD(conn, vol, fd, 1) < 0)
+        goto cleanup;
+
+    /* XXX use unique iSCSI id instead */
+    vol->key = strdup(vol->target.path);
+    if (vol->key == NULL) {
+        virStorageReportError(conn, VIR_ERR_NO_MEMORY, _("key"));
+        goto cleanup;
+    }
+
+
+    pool->def->capacity += vol->capacity;
+    pool->def->allocation += vol->allocation;
+
+    vol->next = pool->volumes;
+    pool->volumes = vol;
+    pool->nvolumes++;
+
+    close(fd);
+
+    return 0;
+
+ cleanup:
+    if (fd != -1) close(fd);
+    free(devpath);
+    virStorageVolDefFree(vol);
+    return -1;
+}
+
+static int
+virStorageBackendISCSIFindLUNs(virConnectPtr conn,
+                               virStoragePoolObjPtr pool,
+                               const char *session)
+{
+    /*
+     * # iscsiadm --mode session -r $session -P 3
+     *
+     *           scsi1 Channel 00 Id 0 Lun: 0
+     *           scsi1 Channel 00 Id 0 Lun: 1
+     *                   Attached scsi disk sdc          State: running
+     *           scsi1 Channel 00 Id 0 Lun: 2
+     *                   Attached scsi disk sdd          State: running
+     *           scsi1 Channel 00 Id 0 Lun: 3
+     *                   Attached scsi disk sde          State: running
+     *           scsi1 Channel 00 Id 0 Lun: 4
+     *                   Attached scsi disk sdf          State: running
+     *           scsi1 Channel 00 Id 0 Lun: 5
+     *                   Attached scsi disk sdg          State: running
+     *
+     * Need 2 regex to match alternating lines
+     */
+    const char *regexes[] = {
+        "^\\s*scsi(\\S+)\\s+Channel\\s+(\\S+)\\s+Id\\s+(\\S+)\\s+Lun:\\s+(\\S+)\\s*$",
+        "^\\s*Attached\\s+scsi\\s+disk\\s+(\\S+)\\s+State:\\s+running\\s*$"
+    };
+    int vars[] = {
+        4, 1
+    };
+    const char *prog[] = {
+        ISCSIADM, "--mode", "session", "-r", session, "-P", "3", NULL,
+    };
+
+    return virStorageBackendRunProgRegex(conn, pool,
+                                         prog,
+                                         2,
+                                         regexes,
+                                         vars,
+                                         virStorageBackendISCSIMakeLUN,
+                                         NULL);
+}
+
+
+static int
+virStorageBackendISCSIRescanLUNs(virConnectPtr conn,
+                                 virStoragePoolObjPtr pool ATTRIBUTE_UNUSED,
+                                 const char *session)
+{
+    const char *cmdargv[] = {
+        ISCSIADM, "--mode", "session", "-r", session, "-R", NULL,
+    };
+
+    if (virRun(conn, (char **)cmdargv, NULL) < 0)
+        return -1;
+
+    return 0;
+}
+
+
+static int
+virStorageBackendISCSILogin(virConnectPtr conn,
+                            virStoragePoolObjPtr pool,
+                            const char *portal)
+{
+    return virStorageBackendISCSIConnection(conn, pool, portal, "--login");
+}
+
+static int
+virStorageBackendISCSILogout(virConnectPtr conn,
+                             virStoragePoolObjPtr pool,
+                             const char *portal)
+{
+    return virStorageBackendISCSIConnection(conn, pool, portal, "--logout");
+}
+
+static char *
+virStorageBackendISCSIPortal(virConnectPtr conn,
+                             virStoragePoolObjPtr pool)
+{
+    char ipaddr[NI_MAXHOST];
+    char *portal;
+
+    if (virStorageBackendISCSITargetIP(conn,
+                                       pool->def->source.host.name,
+                                       ipaddr, sizeof(ipaddr)) < 0)
+        return NULL;
+
+    portal = malloc(strlen(ipaddr) + 1 + 4 + 2 + 1);
+    if (portal == NULL) {
+        virStorageReportError(conn, VIR_ERR_NO_MEMORY, _("portal"));
+        return NULL;
+    }
+
+    strcpy(portal, ipaddr);
+    strcat(portal, ":3260,1");
+
+    return portal;
+}
+
+
+static int
+virStorageBackendISCSIStartPool(virConnectPtr conn,
+                                virStoragePoolObjPtr pool)
+{
+    char *portal = NULL;
+
+    if (pool->def->source.host.name == NULL) {
+        virStorageReportError(conn, VIR_ERR_INTERNAL_ERROR,
+                              _("missing source host"));
+        return -1;
+    }
+
+    if (pool->def->source.ndevice != 1 ||
+        pool->def->source.devices[0].path == NULL) {
+        virStorageReportError(conn, VIR_ERR_INTERNAL_ERROR,
+                              _("missing source device"));
+        return -1;
+    }
+
+    if ((portal = virStorageBackendISCSIPortal(conn, pool)) == NULL)
+        return -1;
+    if (virStorageBackendISCSILogin(conn, pool, portal) < 0) {
+        free(portal);
+        return -1;
+    }
+    free(portal);
+    return 0;
+}
+
+static int
+virStorageBackendISCSIRefreshPool(virConnectPtr conn,
+                                  virStoragePoolObjPtr pool)
+{
+    char *session = NULL;
+
+    pool->def->allocation = pool->def->capacity = pool->def->available = 0;
+
+    if ((session = virStorageBackendISCSISession(conn, pool)) == NULL)
+        goto cleanup;
+    if (virStorageBackendISCSIRescanLUNs(conn, pool, session) < 0)
+        goto cleanup;
+    if (virStorageBackendISCSIFindLUNs(conn, pool, session) < 0)
+        goto cleanup;
+    free(session);
+
+    return 0;
+
+ cleanup:
+    free(session);
+    return -1;
+}
+
+
+static int
+virStorageBackendISCSIStopPool(virConnectPtr conn,
+                               virStoragePoolObjPtr pool)
+{
+    char *portal;
+
+    if ((portal = virStorageBackendISCSIPortal(conn, pool)) == NULL)
+        return -1;
+
+    if (virStorageBackendISCSILogout(conn, pool, portal) < 0) {
+        free(portal);
+        return -1;
+    }
+    free(portal);
+
+    return 0;
+}
+
+
+virStorageBackend virStorageBackendISCSI = {
+  .type = VIR_STORAGE_POOL_ISCSI,
+
+  .startPool = virStorageBackendISCSIStartPool,
+  .refreshPool = virStorageBackendISCSIRefreshPool,
+  .stopPool = virStorageBackendISCSIStopPool,
+
+  .poolOptions = {
+        .flags = (VIR_STORAGE_BACKEND_POOL_SOURCE_HOST |
+                  VIR_STORAGE_BACKEND_POOL_SOURCE_DEVICE)
+    },
+
+  .volType = VIR_STORAGE_VOL_BLOCK,
+};
+
+/*
+ * vim: set tabstop=4:
+ * vim: set shiftwidth=4:
+ * vim: set expandtab:
+ */
+/*
+ * Local variables:
+ *  indent-tabs-mode: nil
+ *  c-indent-level: 4
+ *  c-basic-offset: 4
+ *  tab-width: 4
+ * End:
+ */

src/storage_backend_iscsi.h

@@ -0,0 +1,45 @@
+/*
+ * storage_backend_iscsi.h: storage backend for iSCSI handling
+ *
+ * Copyright (C) 2007-2008 Red Hat, Inc.
+ * Copyright (C) 2007-2008 Daniel P. Berrange
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA
+ *
+ * Author: Daniel P. Berrange <berrange@redhat.com>
+ */
+
+#ifndef __VIR_STORAGE_BACKEND_ISCSI_H__
+#define __VIR_STORAGE_BACKEND_ISCSI_H__
+
+#include "storage_backend.h"
+
+extern virStorageBackend virStorageBackendISCSI;
+
+#endif /* __VIR_STORAGE_BACKEND_ISCSI_H__ */
+
+/*
+ * vim: set tabstop=4:
+ * vim: set shiftwidth=4:
+ * vim: set expandtab:
+ */
+/*
+ * Local variables:
+ *  indent-tabs-mode: nil
+ *  c-indent-level: 4
+ *  c-basic-offset: 4
+ *  tab-width: 4
+ * End:
+ */