storage: scsi: Fix build if SCSI backend is disabled but iSCSI is enabled

The iSCSI backend driver was using stuff from the SCSI driver without
making sure that it's compiled in. Move the common code into the
storage_util.c since it does not contain any specific code.

src/storage/storage_backend_iscsi.c

@@ -32,7 +32,6 @@
 
 #include "datatypes.h"
 #include "driver.h"
-#include "storage_backend_scsi.h"
 #include "storage_backend_iscsi.h"
 #include "viralloc.h"
 #include "vircommand.h"

src/storage/storage_backend_scsi.c

@@ -25,7 +25,6 @@
 
 #include <unistd.h>
 #include <stdio.h>
-#include <dirent.h>
 #include <fcntl.h>
 
 #include "virerror.h"
@@ -48,452 +47,6 @@ struct _virStoragePoolFCRefreshInfo {
     unsigned char pool_uuid[VIR_UUID_BUFLEN];
 };
 
-/* Function to check if the type file in the given sysfs_path is a
- * Direct-Access device (i.e. type 0).  Return -1 on failure, type of
- * the device otherwise.
- */
-static int
-getDeviceType(uint32_t host,
-              uint32_t bus,
-              uint32_t target,
-              uint32_t lun,
-              int *type)
-{
-    char *type_path = NULL;
-    char typestr[3];
-    char *gottype, *p;
-    FILE *typefile;
-    int retval = 0;
-
-    if (virAsprintf(&type_path, "/sys/bus/scsi/devices/%u:%u:%u:%u/type",
-                    host, bus, target, lun) < 0)
-        goto out;
-
-    typefile = fopen(type_path, "r");
-    if (typefile == NULL) {
-        virReportSystemError(errno,
-                             _("Could not find typefile '%s'"),
-                             type_path);
-        /* there was no type file; that doesn't seem right */
-        retval = -1;
-        goto out;
-    }
-
-    gottype = fgets(typestr, 3, typefile);
-    VIR_FORCE_FCLOSE(typefile);
-
-    if (gottype == NULL) {
-        virReportSystemError(errno,
-                             _("Could not read typefile '%s'"),
-                             type_path);
-        /* we couldn't read the type file; have to give up */
-        retval = -1;
-        goto out;
-    }
-
-    /* we don't actually care about p, but if you pass NULL and the last
-     * character is not \0, virStrToLong_i complains
-     */
-    if (virStrToLong_i(typestr, &p, 10, type) < 0) {
-        virReportError(VIR_ERR_INTERNAL_ERROR,
-                       _("Device type '%s' is not an integer"),
-                       typestr);
-        /* Hm, type wasn't an integer; seems strange */
-        retval = -1;
-        goto out;
-    }
-
-    VIR_DEBUG("Device type is %d", *type);
-
- out:
-    VIR_FREE(type_path);
-    return retval;
-}
-
-static char *
-virStorageBackendSCSISerial(const char *dev)
-{
-    char *serial = NULL;
-#ifdef WITH_UDEV
-    virCommandPtr cmd = virCommandNewArgList(
-        "/lib/udev/scsi_id",
-        "--replace-whitespace",
-        "--whitelisted",
-        "--device", dev,
-        NULL
-        );
-
-    /* Run the program and capture its output */
-    virCommandSetOutputBuffer(cmd, &serial);
-    if (virCommandRun(cmd, NULL) < 0)
-        goto cleanup;
-#endif
-
-    if (serial && STRNEQ(serial, "")) {
-        char *nl = strchr(serial, '\n');
-        if (nl)
-            *nl = '\0';
-    } else {
-        VIR_FREE(serial);
-        ignore_value(VIR_STRDUP(serial, dev));
-    }
-
-#ifdef WITH_UDEV
- cleanup:
-    virCommandFree(cmd);
-#endif
-
-    return serial;
-}
-
-
-/*
- * Attempt to create a new LUN
- *
- * Returns:
- *
- *  0  => Success
- *  -1 => Failure due to some sort of OOM or other fatal issue found when
- *        attempting to get/update information about a found volume
- *  -2 => Failure to find a stable path, not fatal, caller can try another
- */
-static int
-virStorageBackendSCSINewLun(virStoragePoolObjPtr pool,
-                            uint32_t host ATTRIBUTE_UNUSED,
-                            uint32_t bus,
-                            uint32_t target,
-                            uint32_t lun,
-                            const char *dev)
-{
-    virStorageVolDefPtr vol = NULL;
-    char *devpath = NULL;
-    int retval = -1;
-
-    /* Check if the pool is using a stable target path. The call to
-     * virStorageBackendStablePath will fail if the pool target path
-     * isn't stable and just return the strdup'd 'devpath' anyway.
-     * This would be indistinguishable to failing to find the stable
-     * path to the device if the virDirRead loop to search the
-     * target pool path for our devpath had failed.
-     */
-    if (!virStorageBackendPoolPathIsStable(pool->def->target.path) &&
-        !(STREQ(pool->def->target.path, "/dev") ||
-          STREQ(pool->def->target.path, "/dev/"))) {
-        virReportError(VIR_ERR_INVALID_ARG,
-                       _("unable to use target path '%s' for dev '%s'"),
-                       NULLSTR(pool->def->target.path), dev);
-        goto cleanup;
-    }
-
-    if (VIR_ALLOC(vol) < 0)
-        goto cleanup;
-
-    vol->type = VIR_STORAGE_VOL_BLOCK;
-
-    /* 'host' is dynamically allocated by the kernel, first come,
-     * first served, per HBA. As such it isn't suitable for use
-     * in the volume name. We only need uniqueness per-pool, so
-     * just leave 'host' out
-     */
-    if (virAsprintf(&(vol->name), "unit:%u:%u:%u", bus, target, lun) < 0)
-        goto cleanup;
-
-    if (virAsprintf(&devpath, "/dev/%s", dev) < 0)
-        goto cleanup;
-
-    VIR_DEBUG("Trying to create volume for '%s'", devpath);
-
-    /* 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(pool,
-                                                        devpath,
-                                                        true)) == NULL)
-        goto cleanup;
-
-    if (STREQ(devpath, vol->target.path) &&
-        !(STREQ(pool->def->target.path, "/dev") ||
-          STREQ(pool->def->target.path, "/dev/"))) {
-
-        VIR_DEBUG("No stable path found for '%s' in '%s'",
-                  devpath, pool->def->target.path);
-
-        retval = -2;
-        goto cleanup;
-    }
-
-    /* Allow a volume read failure to ignore or skip this block file */
-    if ((retval = virStorageBackendUpdateVolInfo(vol, true,
-                                                 VIR_STORAGE_VOL_OPEN_DEFAULT,
-                                                 VIR_STORAGE_VOL_READ_NOERROR)) < 0)
-        goto cleanup;
-
-    if (!(vol->key = virStorageBackendSCSISerial(vol->target.path)))
-        goto cleanup;
-
-    pool->def->capacity += vol->target.capacity;
-    pool->def->allocation += vol->target.allocation;
-
-    if (VIR_APPEND_ELEMENT(pool->volumes.objs, pool->volumes.count, vol) < 0)
-        goto cleanup;
-
-    vol = NULL;
-    retval = 0;
-
- cleanup:
-    virStorageVolDefFree(vol);
-    VIR_FREE(devpath);
-    return retval;
-}
-
-
-static int
-getNewStyleBlockDevice(const char *lun_path,
-                       const char *block_name ATTRIBUTE_UNUSED,
-                       char **block_device)
-{
-    char *block_path = NULL;
-    DIR *block_dir = NULL;
-    struct dirent *block_dirent = NULL;
-    int retval = -1;
-    int direrr;
-
-    if (virAsprintf(&block_path, "%s/block", lun_path) < 0)
-        goto cleanup;
-
-    VIR_DEBUG("Looking for block device in '%s'", block_path);
-
-    if (virDirOpen(&block_dir, block_path) < 0)
-        goto cleanup;
-
-    while ((direrr = virDirRead(block_dir, &block_dirent, block_path)) > 0) {
-        if (VIR_STRDUP(*block_device, block_dirent->d_name) < 0)
-            goto cleanup;
-
-        VIR_DEBUG("Block device is '%s'", *block_device);
-
-        break;
-    }
-
-    if (direrr < 0)
-        goto cleanup;
-
-    retval = 0;
-
- cleanup:
-    VIR_DIR_CLOSE(block_dir);
-    VIR_FREE(block_path);
-    return retval;
-}
-
-
-static int
-getOldStyleBlockDevice(const char *lun_path ATTRIBUTE_UNUSED,
-                       const char *block_name,
-                       char **block_device)
-{
-    char *blockp = NULL;
-    int retval = -1;
-
-    /* old-style; just parse out the sd */
-    if (!(blockp = strrchr(block_name, ':'))) {
-        /* Hm, wasn't what we were expecting; have to give up */
-        virReportError(VIR_ERR_INTERNAL_ERROR,
-                       _("Failed to parse block name %s"),
-                       block_name);
-        goto cleanup;
-    } else {
-        blockp++;
-        if (VIR_STRDUP(*block_device, blockp) < 0)
-            goto cleanup;
-
-        VIR_DEBUG("Block device is '%s'", *block_device);
-    }
-
-    retval = 0;
- cleanup:
-    return retval;
-}
-
-
-/*
- * Search a device entry for the "block" file
- *
- * Returns
- *
- *   0 => Found it
- *   -1 => Fatal error
- *   -2 => Didn't find in lun_path directory
- */
-static int
-getBlockDevice(uint32_t host,
-               uint32_t bus,
-               uint32_t target,
-               uint32_t lun,
-               char **block_device)
-{
-    char *lun_path = NULL;
-    DIR *lun_dir = NULL;
-    struct dirent *lun_dirent = NULL;
-    int retval = -1;
-    int direrr;
-
-    *block_device = NULL;
-
-    if (virAsprintf(&lun_path, "/sys/bus/scsi/devices/%u:%u:%u:%u",
-                    host, bus, target, lun) < 0)
-        goto cleanup;
-
-    if (virDirOpen(&lun_dir, lun_path) < 0)
-        goto cleanup;
-
-    while ((direrr = virDirRead(lun_dir, &lun_dirent, lun_path)) > 0) {
-        if (STRPREFIX(lun_dirent->d_name, "block")) {
-            if (strlen(lun_dirent->d_name) == 5) {
-                if (getNewStyleBlockDevice(lun_path,
-                                           lun_dirent->d_name,
-                                           block_device) < 0)
-                    goto cleanup;
-            } else {
-                if (getOldStyleBlockDevice(lun_path,
-                                           lun_dirent->d_name,
-                                           block_device) < 0)
-                    goto cleanup;
-            }
-            break;
-        }
-    }
-    if (direrr < 0)
-        goto cleanup;
-    if (!*block_device) {
-        retval = -2;
-        goto cleanup;
-    }
-
-    retval = 0;
-
- cleanup:
-    VIR_DIR_CLOSE(lun_dir);
-    VIR_FREE(lun_path);
-    return retval;
-}
-
-
-/*
- * Process a Logical Unit entry from the scsi host device directory
- *
- * Returns:
- *
- *  0  => Found a valid entry
- *  -1 => Some sort of fatal error
- *  -2 => non-fatal error or a non-disk entry
- */
-static int
-processLU(virStoragePoolObjPtr pool,
-          uint32_t host,
-          uint32_t bus,
-          uint32_t target,
-          uint32_t lun)
-{
-    int retval = -1;
-    int device_type;
-    char *block_device = NULL;
-
-    VIR_DEBUG("Processing LU %u:%u:%u:%u",
-              host, bus, target, lun);
-
-    if (getDeviceType(host, bus, target, lun, &device_type) < 0) {
-        virReportError(VIR_ERR_INTERNAL_ERROR,
-                       _("Failed to determine if %u:%u:%u:%u is a Direct-Access LUN"),
-                       host, bus, target, lun);
-        return -1;
-    }
-
-    /* We don't create volumes for devices other than disk and cdrom
-     * devices, but finding a device that isn't one of those types
-     * isn't an error, either. */
-    if (!(device_type == VIR_STORAGE_DEVICE_TYPE_DISK ||
-          device_type == VIR_STORAGE_DEVICE_TYPE_ROM))
-        return -2;
-
-    VIR_DEBUG("%u:%u:%u:%u is a Direct-Access LUN",
-              host, bus, target, lun);
-
-    if ((retval = getBlockDevice(host, bus, target, lun, &block_device)) < 0) {
-        VIR_DEBUG("Failed to find block device for this LUN");
-        return retval;
-    }
-
-    retval = virStorageBackendSCSINewLun(pool, host, bus, target, lun,
-                                         block_device);
-    if (retval < 0) {
-        VIR_DEBUG("Failed to create new storage volume for %u:%u:%u:%u",
-                  host, bus, target, lun);
-        goto cleanup;
-    }
-
-    VIR_DEBUG("Created new storage volume for %u:%u:%u:%u successfully",
-              host, bus, target, lun);
-
- cleanup:
-    VIR_FREE(block_device);
-    return retval;
-}
-
-
-int
-virStorageBackendSCSIFindLUs(virStoragePoolObjPtr pool,
-                              uint32_t scanhost)
-{
-    int retval = 0;
-    uint32_t bus, target, lun;
-    const char *device_path = "/sys/bus/scsi/devices";
-    DIR *devicedir = NULL;
-    struct dirent *lun_dirent = NULL;
-    char devicepattern[64];
-    int found = 0;
-
-    VIR_DEBUG("Discovering LUs on host %u", scanhost);
-
-    virFileWaitForDevices();
-
-    if (virDirOpen(&devicedir, device_path) < 0)
-        return -1;
-
-    snprintf(devicepattern, sizeof(devicepattern), "%u:%%u:%%u:%%u\n", scanhost);
-
-    while ((retval = virDirRead(devicedir, &lun_dirent, device_path)) > 0) {
-        int rc;
-
-        if (sscanf(lun_dirent->d_name, devicepattern,
-                   &bus, &target, &lun) != 3) {
-            continue;
-        }
-
-        VIR_DEBUG("Found possible LU '%s'", lun_dirent->d_name);
-
-        rc = processLU(pool, scanhost, bus, target, lun);
-        if (rc == -1) {
-            retval = -1;
-            break;
-        }
-        if (rc == 0)
-            found++;
-    }
-
-    VIR_DIR_CLOSE(devicedir);
-
-    if (retval < 0)
-        return -1;
-
-    VIR_DEBUG("Found %d LUs for pool %s", found, pool->def->name);
-
-    return found;
-}
-
 
 static int
 virStorageBackendSCSITriggerRescan(uint32_t host)

src/storage/storage_backend_scsi.h

@@ -32,8 +32,4 @@
 
 extern virStorageBackend virStorageBackendSCSI;
 
-int
-virStorageBackendSCSIFindLUs(virStoragePoolObjPtr pool,
-                             uint32_t scanhost);
-
 #endif /* __VIR_STORAGE_BACKEND_SCSI_H__ */

src/storage/storage_util.c

@@ -2917,3 +2917,452 @@ virStorageBackendDeviceIsEmpty(const char *devpath,
 
     return ret == 0;
 }
+
+
+static char *
+virStorageBackendSCSISerial(const char *dev)
+{
+    char *serial = NULL;
+#ifdef WITH_UDEV
+    virCommandPtr cmd = virCommandNewArgList(
+        "/lib/udev/scsi_id",
+        "--replace-whitespace",
+        "--whitelisted",
+        "--device", dev,
+        NULL
+        );
+
+    /* Run the program and capture its output */
+    virCommandSetOutputBuffer(cmd, &serial);
+    if (virCommandRun(cmd, NULL) < 0)
+        goto cleanup;
+#endif
+
+    if (serial && STRNEQ(serial, "")) {
+        char *nl = strchr(serial, '\n');
+        if (nl)
+            *nl = '\0';
+    } else {
+        VIR_FREE(serial);
+        ignore_value(VIR_STRDUP(serial, dev));
+    }
+
+#ifdef WITH_UDEV
+ cleanup:
+    virCommandFree(cmd);
+#endif
+
+    return serial;
+}
+
+
+/*
+ * Attempt to create a new LUN
+ *
+ * Returns:
+ *
+ *  0  => Success
+ *  -1 => Failure due to some sort of OOM or other fatal issue found when
+ *        attempting to get/update information about a found volume
+ *  -2 => Failure to find a stable path, not fatal, caller can try another
+ */
+static int
+virStorageBackendSCSINewLun(virStoragePoolObjPtr pool,
+                            uint32_t host ATTRIBUTE_UNUSED,
+                            uint32_t bus,
+                            uint32_t target,
+                            uint32_t lun,
+                            const char *dev)
+{
+    virStorageVolDefPtr vol = NULL;
+    char *devpath = NULL;
+    int retval = -1;
+
+    /* Check if the pool is using a stable target path. The call to
+     * virStorageBackendStablePath will fail if the pool target path
+     * isn't stable and just return the strdup'd 'devpath' anyway.
+     * This would be indistinguishable to failing to find the stable
+     * path to the device if the virDirRead loop to search the
+     * target pool path for our devpath had failed.
+     */
+    if (!virStorageBackendPoolPathIsStable(pool->def->target.path) &&
+        !(STREQ(pool->def->target.path, "/dev") ||
+          STREQ(pool->def->target.path, "/dev/"))) {
+        virReportError(VIR_ERR_INVALID_ARG,
+                       _("unable to use target path '%s' for dev '%s'"),
+                       NULLSTR(pool->def->target.path), dev);
+        goto cleanup;
+    }
+
+    if (VIR_ALLOC(vol) < 0)
+        goto cleanup;
+
+    vol->type = VIR_STORAGE_VOL_BLOCK;
+
+    /* 'host' is dynamically allocated by the kernel, first come,
+     * first served, per HBA. As such it isn't suitable for use
+     * in the volume name. We only need uniqueness per-pool, so
+     * just leave 'host' out
+     */
+    if (virAsprintf(&(vol->name), "unit:%u:%u:%u", bus, target, lun) < 0)
+        goto cleanup;
+
+    if (virAsprintf(&devpath, "/dev/%s", dev) < 0)
+        goto cleanup;
+
+    VIR_DEBUG("Trying to create volume for '%s'", devpath);
+
+    /* 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(pool,
+                                                        devpath,
+                                                        true)) == NULL)
+        goto cleanup;
+
+    if (STREQ(devpath, vol->target.path) &&
+        !(STREQ(pool->def->target.path, "/dev") ||
+          STREQ(pool->def->target.path, "/dev/"))) {
+
+        VIR_DEBUG("No stable path found for '%s' in '%s'",
+                  devpath, pool->def->target.path);
+
+        retval = -2;
+        goto cleanup;
+    }
+
+    /* Allow a volume read failure to ignore or skip this block file */
+    if ((retval = virStorageBackendUpdateVolInfo(vol, true,
+                                                 VIR_STORAGE_VOL_OPEN_DEFAULT,
+                                                 VIR_STORAGE_VOL_READ_NOERROR)) < 0)
+        goto cleanup;
+
+    if (!(vol->key = virStorageBackendSCSISerial(vol->target.path)))
+        goto cleanup;
+
+    pool->def->capacity += vol->target.capacity;
+    pool->def->allocation += vol->target.allocation;
+
+    if (VIR_APPEND_ELEMENT(pool->volumes.objs, pool->volumes.count, vol) < 0)
+        goto cleanup;
+
+    vol = NULL;
+    retval = 0;
+
+ cleanup:
+    virStorageVolDefFree(vol);
+    VIR_FREE(devpath);
+    return retval;
+}
+
+
+
+static int
+getNewStyleBlockDevice(const char *lun_path,
+                       const char *block_name ATTRIBUTE_UNUSED,
+                       char **block_device)
+{
+    char *block_path = NULL;
+    DIR *block_dir = NULL;
+    struct dirent *block_dirent = NULL;
+    int retval = -1;
+    int direrr;
+
+    if (virAsprintf(&block_path, "%s/block", lun_path) < 0)
+        goto cleanup;
+
+    VIR_DEBUG("Looking for block device in '%s'", block_path);
+
+    if (virDirOpen(&block_dir, block_path) < 0)
+        goto cleanup;
+
+    while ((direrr = virDirRead(block_dir, &block_dirent, block_path)) > 0) {
+        if (VIR_STRDUP(*block_device, block_dirent->d_name) < 0)
+            goto cleanup;
+
+        VIR_DEBUG("Block device is '%s'", *block_device);
+
+        break;
+    }
+
+    if (direrr < 0)
+        goto cleanup;
+
+    retval = 0;
+
+ cleanup:
+    VIR_DIR_CLOSE(block_dir);
+    VIR_FREE(block_path);
+    return retval;
+}
+
+
+static int
+getOldStyleBlockDevice(const char *lun_path ATTRIBUTE_UNUSED,
+                       const char *block_name,
+                       char **block_device)
+{
+    char *blockp = NULL;
+    int retval = -1;
+
+    /* old-style; just parse out the sd */
+    if (!(blockp = strrchr(block_name, ':'))) {
+        /* Hm, wasn't what we were expecting; have to give up */
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                       _("Failed to parse block name %s"),
+                       block_name);
+        goto cleanup;
+    } else {
+        blockp++;
+        if (VIR_STRDUP(*block_device, blockp) < 0)
+            goto cleanup;
+
+        VIR_DEBUG("Block device is '%s'", *block_device);
+    }
+
+    retval = 0;
+ cleanup:
+    return retval;
+}
+
+
+/*
+ * Search a device entry for the "block" file
+ *
+ * Returns
+ *
+ *   0 => Found it
+ *   -1 => Fatal error
+ *   -2 => Didn't find in lun_path directory
+ */
+static int
+getBlockDevice(uint32_t host,
+               uint32_t bus,
+               uint32_t target,
+               uint32_t lun,
+               char **block_device)
+{
+    char *lun_path = NULL;
+    DIR *lun_dir = NULL;
+    struct dirent *lun_dirent = NULL;
+    int retval = -1;
+    int direrr;
+
+    *block_device = NULL;
+
+    if (virAsprintf(&lun_path, "/sys/bus/scsi/devices/%u:%u:%u:%u",
+                    host, bus, target, lun) < 0)
+        goto cleanup;
+
+    if (virDirOpen(&lun_dir, lun_path) < 0)
+        goto cleanup;
+
+    while ((direrr = virDirRead(lun_dir, &lun_dirent, lun_path)) > 0) {
+        if (STRPREFIX(lun_dirent->d_name, "block")) {
+            if (strlen(lun_dirent->d_name) == 5) {
+                if (getNewStyleBlockDevice(lun_path,
+                                           lun_dirent->d_name,
+                                           block_device) < 0)
+                    goto cleanup;
+            } else {
+                if (getOldStyleBlockDevice(lun_path,
+                                           lun_dirent->d_name,
+                                           block_device) < 0)
+                    goto cleanup;
+            }
+            break;
+        }
+    }
+    if (direrr < 0)
+        goto cleanup;
+    if (!*block_device) {
+        retval = -2;
+        goto cleanup;
+    }
+
+    retval = 0;
+
+ cleanup:
+    VIR_DIR_CLOSE(lun_dir);
+    VIR_FREE(lun_path);
+    return retval;
+}
+
+
+/* Function to check if the type file in the given sysfs_path is a
+ * Direct-Access device (i.e. type 0).  Return -1 on failure, type of
+ * the device otherwise.
+ */
+static int
+getDeviceType(uint32_t host,
+              uint32_t bus,
+              uint32_t target,
+              uint32_t lun,
+              int *type)
+{
+    char *type_path = NULL;
+    char typestr[3];
+    char *gottype, *p;
+    FILE *typefile;
+    int retval = 0;
+
+    if (virAsprintf(&type_path, "/sys/bus/scsi/devices/%u:%u:%u:%u/type",
+                    host, bus, target, lun) < 0)
+        goto out;
+
+    typefile = fopen(type_path, "r");
+    if (typefile == NULL) {
+        virReportSystemError(errno,
+                             _("Could not find typefile '%s'"),
+                             type_path);
+        /* there was no type file; that doesn't seem right */
+        retval = -1;
+        goto out;
+    }
+
+    gottype = fgets(typestr, 3, typefile);
+    VIR_FORCE_FCLOSE(typefile);
+
+    if (gottype == NULL) {
+        virReportSystemError(errno,
+                             _("Could not read typefile '%s'"),
+                             type_path);
+        /* we couldn't read the type file; have to give up */
+        retval = -1;
+        goto out;
+    }
+
+    /* we don't actually care about p, but if you pass NULL and the last
+     * character is not \0, virStrToLong_i complains
+     */
+    if (virStrToLong_i(typestr, &p, 10, type) < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                       _("Device type '%s' is not an integer"),
+                       typestr);
+        /* Hm, type wasn't an integer; seems strange */
+        retval = -1;
+        goto out;
+    }
+
+    VIR_DEBUG("Device type is %d", *type);
+
+ out:
+    VIR_FREE(type_path);
+    return retval;
+}
+
+
+/*
+ * Process a Logical Unit entry from the scsi host device directory
+ *
+ * Returns:
+ *
+ *  0  => Found a valid entry
+ *  -1 => Some sort of fatal error
+ *  -2 => non-fatal error or a non-disk entry
+ */
+static int
+processLU(virStoragePoolObjPtr pool,
+          uint32_t host,
+          uint32_t bus,
+          uint32_t target,
+          uint32_t lun)
+{
+    int retval = -1;
+    int device_type;
+    char *block_device = NULL;
+
+    VIR_DEBUG("Processing LU %u:%u:%u:%u",
+              host, bus, target, lun);
+
+    if (getDeviceType(host, bus, target, lun, &device_type) < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                       _("Failed to determine if %u:%u:%u:%u is a Direct-Access LUN"),
+                       host, bus, target, lun);
+        return -1;
+    }
+
+    /* We don't create volumes for devices other than disk and cdrom
+     * devices, but finding a device that isn't one of those types
+     * isn't an error, either. */
+    if (!(device_type == VIR_STORAGE_DEVICE_TYPE_DISK ||
+          device_type == VIR_STORAGE_DEVICE_TYPE_ROM))
+        return -2;
+
+    VIR_DEBUG("%u:%u:%u:%u is a Direct-Access LUN",
+              host, bus, target, lun);
+
+    if ((retval = getBlockDevice(host, bus, target, lun, &block_device)) < 0) {
+        VIR_DEBUG("Failed to find block device for this LUN");
+        return retval;
+    }
+
+    retval = virStorageBackendSCSINewLun(pool, host, bus, target, lun,
+                                         block_device);
+    if (retval < 0) {
+        VIR_DEBUG("Failed to create new storage volume for %u:%u:%u:%u",
+                  host, bus, target, lun);
+        goto cleanup;
+    }
+
+    VIR_DEBUG("Created new storage volume for %u:%u:%u:%u successfully",
+              host, bus, target, lun);
+
+ cleanup:
+    VIR_FREE(block_device);
+    return retval;
+}
+
+
+int
+virStorageBackendSCSIFindLUs(virStoragePoolObjPtr pool,
+                              uint32_t scanhost)
+{
+    int retval = 0;
+    uint32_t bus, target, lun;
+    const char *device_path = "/sys/bus/scsi/devices";
+    DIR *devicedir = NULL;
+    struct dirent *lun_dirent = NULL;
+    char devicepattern[64];
+    int found = 0;
+
+    VIR_DEBUG("Discovering LUs on host %u", scanhost);
+
+    virFileWaitForDevices();
+
+    if (virDirOpen(&devicedir, device_path) < 0)
+        return -1;
+
+    snprintf(devicepattern, sizeof(devicepattern), "%u:%%u:%%u:%%u\n", scanhost);
+
+    while ((retval = virDirRead(devicedir, &lun_dirent, device_path)) > 0) {
+        int rc;
+
+        if (sscanf(lun_dirent->d_name, devicepattern,
+                   &bus, &target, &lun) != 3) {
+            continue;
+        }
+
+        VIR_DEBUG("Found possible LU '%s'", lun_dirent->d_name);
+
+        rc = processLU(pool, scanhost, bus, target, lun);
+        if (rc == -1) {
+            retval = -1;
+            break;
+        }
+        if (rc == 0)
+            found++;
+    }
+
+    VIR_DIR_CLOSE(devicedir);
+
+    if (retval < 0)
+        return -1;
+
+    VIR_DEBUG("Found %d LUs for pool %s", found, pool->def->name);
+
+    return found;
+}

src/storage/storage_util.h

@@ -146,4 +146,7 @@ virStorageBackendCreateQemuImgCmdFromVol(virConnectPtr conn,
                                          int imgformat,
                                          const char *secretPath);
 
+int virStorageBackendSCSIFindLUs(virStoragePoolObjPtr pool,
+                                 uint32_t scanhost);
+
 #endif /* __VIR_STORAGE_UTIL_H__ */