libvirt/SOURCES/libvirt-RHEL-virscsi-Support-TAPEs-in-virSCSIDeviceGetDevName.patch

From c481bcacd1f515d2e93036dc452a25e9ff06f7ae Mon Sep 17 00:00:00 2001
Message-Id: <c481bcacd1f515d2e93036dc452a25e9ff06f7ae@dist-git>
From: Michal Privoznik <mprivozn@redhat.com>
Date: Fri, 6 Mar 2020 15:52:22 +0100
Subject: [PATCH] RHEL: virscsi: Support TAPEs in virSCSIDeviceGetDevName()

If the SCSI device we want to get /dev node name for is TAPE
device we need to look at 'tape' symlink in the sysfs dir
corresponding to the device.

https://bugzilla.redhat.com/show_bug.cgi?id=1808390

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Message-Id: <20200306145226.1610708-3-abologna@redhat.com>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
---
 src/util/virscsi.c                          | 28 +++++++++++++++
 tests/virscsidata/2-0-0-0/model             |  1 +
 tests/virscsidata/2-0-0-0/scsi_tape/st0/dev |  1 +
 tests/virscsidata/2-0-0-0/sg3/dev           |  1 +
 tests/virscsidata/2-0-0-0/tape              |  1 +
 tests/virscsidata/2-0-0-0/type              |  1 +
 tests/virscsidata/2-0-0-0/vendor            |  1 +
 tests/virscsidata/sg3                       |  0
 tests/virscsitest.c                         | 38 ++++++++++++++++++---
 9 files changed, 67 insertions(+), 5 deletions(-)
 create mode 100644 tests/virscsidata/2-0-0-0/model
 create mode 100644 tests/virscsidata/2-0-0-0/scsi_tape/st0/dev
 create mode 100644 tests/virscsidata/2-0-0-0/sg3/dev
 create mode 120000 tests/virscsidata/2-0-0-0/tape
 create mode 100644 tests/virscsidata/2-0-0-0/type
 create mode 100644 tests/virscsidata/2-0-0-0/vendor
 create mode 100644 tests/virscsidata/sg3

diff --git a/src/util/virscsi.c b/src/util/virscsi.c
index c40857977f..57958c06ea 100644
--- a/src/util/virscsi.c
+++ b/src/util/virscsi.c
@@ -238,6 +238,31 @@ virSCSIDeviceGetDevNameBlock(const char *prefix,
 }
 
 
+static char *
+virSCSIDeviceGetDevNameTape(const char *prefix,
+                            unsigned int adapter,
+                            unsigned int bus,
+                            unsigned int target,
+                            unsigned long long unit)
+{
+    g_autofree char *path = NULL;
+    g_autofree char *resolvedPath = NULL;
+    g_autoptr(GError) err = NULL;
+
+    path = g_strdup_printf("%s/%d:%u:%u:%llu/tape",
+                           prefix, adapter, bus, target, unit);
+
+    if (!(resolvedPath = g_file_read_link(path, &err))) {
+        virReportError(VIR_ERR_SYSTEM_ERROR,
+                       _("Unable to read link: %s"),
+                       err->message);
+        return NULL;
+    }
+
+    return g_path_get_basename(resolvedPath);
+}
+
+
 /* Returns device name (e.g. "sdc") on success, or NULL
  * on failure.
  */
@@ -266,6 +291,9 @@ virSCSIDeviceGetDevName(const char *sysfs_prefix,
         break;
 
     case VIR_SCSI_DEVICE_TYPE_TAPE:
+        name = virSCSIDeviceGetDevNameTape(prefix, adapter_id, bus, target, unit);
+        break;
+
     case VIR_SCSI_DEVICE_TYPE_PRINTER:
     case VIR_SCSI_DEVICE_TYPE_PROCESSOR:
     case VIR_SCSI_DEVICE_TYPE_WORM:
diff --git a/tests/virscsidata/2-0-0-0/model b/tests/virscsidata/2-0-0-0/model
new file mode 100644
index 0000000000..d2ab4715c3
--- /dev/null
+++ b/tests/virscsidata/2-0-0-0/model
@@ -0,0 +1 @@
+scsi_debug
diff --git a/tests/virscsidata/2-0-0-0/scsi_tape/st0/dev b/tests/virscsidata/2-0-0-0/scsi_tape/st0/dev
new file mode 100644
index 0000000000..3dd777e840
--- /dev/null
+++ b/tests/virscsidata/2-0-0-0/scsi_tape/st0/dev
@@ -0,0 +1 @@
+9:0
diff --git a/tests/virscsidata/2-0-0-0/sg3/dev b/tests/virscsidata/2-0-0-0/sg3/dev
new file mode 100644
index 0000000000..b369a59b3e
--- /dev/null
+++ b/tests/virscsidata/2-0-0-0/sg3/dev
@@ -0,0 +1 @@
+21:3
diff --git a/tests/virscsidata/2-0-0-0/tape b/tests/virscsidata/2-0-0-0/tape
new file mode 120000
index 0000000000..6ca7f77539
--- /dev/null
+++ b/tests/virscsidata/2-0-0-0/tape
@@ -0,0 +1 @@
+scsi_tape/st0
\ No newline at end of file
diff --git a/tests/virscsidata/2-0-0-0/type b/tests/virscsidata/2-0-0-0/type
new file mode 100644
index 0000000000..d00491fd7e
--- /dev/null
+++ b/tests/virscsidata/2-0-0-0/type
@@ -0,0 +1 @@
+1
diff --git a/tests/virscsidata/2-0-0-0/vendor b/tests/virscsidata/2-0-0-0/vendor
new file mode 100644
index 0000000000..9b075671ea
--- /dev/null
+++ b/tests/virscsidata/2-0-0-0/vendor
@@ -0,0 +1 @@
+Linux
diff --git a/tests/virscsidata/sg3 b/tests/virscsidata/sg3
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/tests/virscsitest.c b/tests/virscsitest.c
index d5a0da4753..e501d6d041 100644
--- a/tests/virscsitest.c
+++ b/tests/virscsitest.c
@@ -32,18 +32,34 @@ VIR_LOG_INIT("tests.scsitest");
 
 static char *virscsi_prefix;
 
+typedef struct {
+    const char *adapter;
+    unsigned int bus;
+    unsigned int target;
+    unsigned int unit;
+    const char *expectedName;
+} testGetDevNameData;
+
 static int
-test1(const void *data G_GNUC_UNUSED)
+testGetDevName(const void *opaque)
 {
+    const testGetDevNameData *data = opaque;
     char *name = NULL;
     int ret = -1;
 
     if (!(name = virSCSIDeviceGetDevName(virscsi_prefix,
-                                         "scsi_host1", 0, 0, 0)))
+                                         data->adapter,
+                                         data->bus,
+                                         data->target,
+                                         data->unit)))
         return -1;
 
-    if (STRNEQ(name, "sdh"))
+    if (STRNEQ(name, data->expectedName)) {
+        fprintf(stderr,
+                "SCSI dev name mismatch, expected %s got %s",
+                data->expectedName, name);
         goto cleanup;
+    }
 
     ret = 0;
  cleanup:
@@ -212,15 +228,27 @@ mymain(void)
 
     CREATE_SYMLINK("0-0-0-0", "0:0:0:0");
     CREATE_SYMLINK("1-0-0-0", "1:0:0:0");
+    CREATE_SYMLINK("2-0-0-0", "2:0:0:0");
     CREATE_SYMLINK("sg0", "sg0");
+    CREATE_SYMLINK("sg3", "sg3");
     CREATE_SYMLINK("sg8", "sg8");
 
     VIR_FREE(virscsi_prefix);
 
     virscsi_prefix = g_strdup(tmpdir);
 
-    if (virTestRun("test1", test1, NULL) < 0)
-        ret = -1;
+#define TEST_GET_DEV_NAME(adapter, bus, target, unit, expectedName) \
+    do { \
+        testGetDevNameData data = {adapter, bus, target, unit, expectedName}; \
+        if (virTestRun("test getDevname " expectedName, \
+                       testGetDevName, &data) < 0) \
+            ret = -1; \
+    } while (0)
+
+    TEST_GET_DEV_NAME("scsi_host0", 0, 0, 0, "sda");
+    TEST_GET_DEV_NAME("scsi_host1", 0, 0, 0, "sdh");
+    TEST_GET_DEV_NAME("scsi_host2", 0, 0, 0, "st0");
+
     if (virTestRun("test2", test2, NULL) < 0)
         ret = -1;
 
-- 
2.25.1