From 27dee7b5a4152ceea00662a6f112c994d7f2b818 Mon Sep 17 00:00:00 2001

Message-Id: <27dee7b5a4152ceea00662a6f112c994d7f2b818@dist-git>

From: Michal Privoznik <mprivozn@redhat.com>

Date: Fri, 6 Mar 2020 15:52:23 +0100

Subject: [PATCH] RHEL: virscsi: Introduce and use

 virSCSIDeviceGetUnprivSGIOSysfsPath()

When constructing a path to the 'unpriv_sgio' file of given SCSI

device we don't need to go through /dev/* and major() + minor()

path. The generated path points to

/sys/dev/block/MAJ:MIN/queue/unpriv_sgio which is wrong if the

SCSI device in question is not a block device. We can generate a

different path: /sys/bus/scsi/devices/X:X:X:X/unpriv_sgio where

the file is directly accessible regardless of the SCSI device

type.

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: <20200306145226.1610708-4-abologna@redhat.com>

Reviewed-by: Jiri Denemark <jdenemar@redhat.com>

---

 src/libvirt_private.syms |  1 +

 src/qemu/qemu_conf.c     | 29 ++++++++++++++++++-----------

 src/util/virscsi.c       | 19 +++++++++++++++++++

 src/util/virscsi.h       |  5 +++++

 src/util/virutil.c       | 24 ++++++------------------

 src/util/virutil.h       |  2 --

 6 files changed, 49 insertions(+), 31 deletions(-)

diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms

index 43493ea76e..0f701ed1ae 100644

--- a/src/libvirt_private.syms

+++ b/src/libvirt_private.syms

@@ -3168,6 +3168,7 @@ virSCSIDeviceGetSgName;

 virSCSIDeviceGetShareable;

 virSCSIDeviceGetTarget;

 virSCSIDeviceGetUnit;

+virSCSIDeviceGetUnprivSGIOSysfsPath;

 virSCSIDeviceIsAvailable;

 virSCSIDeviceListAdd;

 virSCSIDeviceListCount;

diff --git a/src/qemu/qemu_conf.c b/src/qemu/qemu_conf.c

index 2beef89cd1..90ff7f56f0 100644

--- a/src/qemu/qemu_conf.c

+++ b/src/qemu/qemu_conf.c

@@ -1500,7 +1500,7 @@ qemuCheckUnprivSGIO(GHashTable *sharedDevices,

     if (!(virHashLookup(sharedDevices, key)))

         return 0;

-    if (virGetDeviceUnprivSGIO(device_path, NULL, &val) < 0)

+    if (virGetDeviceUnprivSGIO(sysfs_path, &val) < 0)

         return -1;

     /* Error message on failure needs to be handled in caller

@@ -1852,39 +1852,46 @@ qemuSetUnprivSGIO(virDomainDeviceDef *dev)

     virDomainDiskDef *disk = NULL;

     virDomainHostdevDef *hostdev = NULL;

     g_autofree char *sysfs_path = NULL;

-    g_autofree char *hostdev_path = NULL;

-    const char *path = NULL;

     int val = 0;

     /* "sgio" is only valid for block disk; cdrom

      * and floopy disk can have empty source.

      */

     if (dev->type == VIR_DOMAIN_DEVICE_DISK) {

+        const char *path;

+

         disk = dev->data.disk;

+        path = virDomainDiskGetSource(disk);

         if (disk->device != VIR_DOMAIN_DISK_DEVICE_LUN ||

             !virStorageSourceIsBlockLocal(disk->src))

             return 0;

-        path = virDomainDiskGetSource(disk);

+        if (!(sysfs_path = virGetUnprivSGIOSysfsPath(path, NULL)))

+            return -1;

+

     } else if (dev->type == VIR_DOMAIN_DEVICE_HOSTDEV) {

+        virDomainHostdevSubsysSCSI *scsisrc;

+        virDomainHostdevSubsysSCSIHost *scsihostsrc;

+

         hostdev = dev->data.hostdev;

+        scsisrc = &hostdev->source.subsys.u.scsi;

+        scsihostsrc = &scsisrc->u.host;

         if (hostdev->source.subsys.u.scsi.protocol ==

             VIR_DOMAIN_HOSTDEV_SCSI_PROTOCOL_TYPE_ISCSI)

             return 0;

-        if (!(hostdev_path = qemuGetHostdevPath(hostdev)))

+        if (!(sysfs_path = virSCSIDeviceGetUnprivSGIOSysfsPath(NULL,

+                                                               scsihostsrc->adapter,

+                                                               scsihostsrc->bus,

+                                                               scsihostsrc->target,

+                                                               scsihostsrc->unit)))

             return -1;

-

-        path = hostdev_path;

     } else {

         return 0;

     }

-    if (!(sysfs_path = virGetUnprivSGIOSysfsPath(path, NULL)))

-        return -1;

-

     /* By default, filter the SG_IO commands, i.e. set unpriv_sgio to 0.  */

     if (dev->type == VIR_DOMAIN_DEVICE_DISK) {

         if (disk->sgio == VIR_DOMAIN_DEVICE_SGIO_UNFILTERED)

@@ -1902,7 +1909,7 @@ qemuSetUnprivSGIO(virDomainDeviceDef *dev)

      * virSetDeviceUnprivSGIO, to report an error for unsupported unpriv_sgio.

      */

     if ((virFileExists(sysfs_path) || val == 1) &&

-        virSetDeviceUnprivSGIO(path, NULL, val) < 0)

+        virSetDeviceUnprivSGIO(sysfs_path, val) < 0)

         return -1;

     return 0;

diff --git a/src/util/virscsi.c b/src/util/virscsi.c

index d6c10c0667..7a8e6b3b23 100644

--- a/src/util/virscsi.c

+++ b/src/util/virscsi.c

@@ -302,6 +302,25 @@ virSCSIDeviceGetDevName(const char *sysfs_prefix,

     }

 }

+

+char *

+virSCSIDeviceGetUnprivSGIOSysfsPath(const char *sysfs_prefix,

+                                    const char *adapter,

+                                    unsigned int bus,

+                                    unsigned int target,

+                                    unsigned long long unit)

+{

+    unsigned int adapter_id;

+    const char *prefix = sysfs_prefix ? sysfs_prefix : SYSFS_SCSI_DEVICES;

+

+    if (virSCSIDeviceGetAdapterId(adapter, &adapter_id) < 0)

+        return NULL;

+

+    return g_strdup_printf("%s/%d:%u:%u:%llu/unpriv_sgio",

+                           prefix, adapter_id, bus, target, unit);

+}

+

+

 virSCSIDevice *

 virSCSIDeviceNew(const char *sysfs_prefix,

                  const char *adapter,

diff --git a/src/util/virscsi.h b/src/util/virscsi.h

index 65ad15ed76..5721985939 100644

--- a/src/util/virscsi.h

+++ b/src/util/virscsi.h

@@ -40,6 +40,11 @@ char *virSCSIDeviceGetDevName(const char *sysfs_prefix,

                               unsigned int bus,

                               unsigned int target,

                               unsigned long long unit);

+char *virSCSIDeviceGetUnprivSGIOSysfsPath(const char *sysfs_prefix,

+                                          const char *adapter,

+                                          unsigned int bus,

+                                          unsigned int target,

+                                          unsigned long long unit);

 virSCSIDevice *virSCSIDeviceNew(const char *sysfs_prefix,

                                   const char *adapter,

diff --git a/src/util/virutil.c b/src/util/virutil.c

index 00cd56e2b2..d0fc49c39f 100644

--- a/src/util/virutil.c

+++ b/src/util/virutil.c

@@ -1382,18 +1382,13 @@ virGetUnprivSGIOSysfsPath(const char *path,

 int

 virSetDeviceUnprivSGIO(const char *path,

-                       const char *sysfs_dir,

                        int unpriv_sgio)

 {

-    char *sysfs_path = NULL;

     char *val = NULL;

     int ret = -1;

     int rc;

-    if (!(sysfs_path = virGetUnprivSGIOSysfsPath(path, sysfs_dir)))

-        return -1;

-

-    if (!virFileExists(sysfs_path)) {

+    if (!virFileExists(path)) {

         virReportError(VIR_ERR_OPERATION_INVALID, "%s",

                        _("unpriv_sgio is not supported by this kernel"));

         goto cleanup;

@@ -1401,38 +1396,32 @@ virSetDeviceUnprivSGIO(const char *path,

     val = g_strdup_printf("%d", unpriv_sgio);

-    if ((rc = virFileWriteStr(sysfs_path, val, 0)) < 0) {

-        virReportSystemError(-rc, _("failed to set %s"), sysfs_path);

+    if ((rc = virFileWriteStr(path, val, 0)) < 0) {

+        virReportSystemError(-rc, _("failed to set %s"), path);

         goto cleanup;

     }

     ret = 0;

  cleanup:

-    VIR_FREE(sysfs_path);

     VIR_FREE(val);

     return ret;

 }

 int

 virGetDeviceUnprivSGIO(const char *path,

-                       const char *sysfs_dir,

                        int *unpriv_sgio)

 {

-    char *sysfs_path = NULL;

     char *buf = NULL;

     char *tmp = NULL;

     int ret = -1;

-    if (!(sysfs_path = virGetUnprivSGIOSysfsPath(path, sysfs_dir)))

-        return -1;

-

-    if (!virFileExists(sysfs_path)) {

+    if (!virFileExists(path)) {

         virReportError(VIR_ERR_OPERATION_INVALID, "%s",

                        _("unpriv_sgio is not supported by this kernel"));

         goto cleanup;

     }

-    if (virFileReadAll(sysfs_path, 1024, &buf) < 0)

+    if (virFileReadAll(path, 1024, &buf) < 0)

         goto cleanup;

     if ((tmp = strchr(buf, '\n')))

@@ -1440,13 +1429,12 @@ virGetDeviceUnprivSGIO(const char *path,

     if (virStrToLong_i(buf, NULL, 10, unpriv_sgio) < 0) {

         virReportError(VIR_ERR_INTERNAL_ERROR,

-                       _("failed to parse value of %s"), sysfs_path);

+                       _("failed to parse value of %s"), path);

         goto cleanup;

     }

     ret = 0;

  cleanup:

-    VIR_FREE(sysfs_path);

     VIR_FREE(buf);

     return ret;

 }

diff --git a/src/util/virutil.h b/src/util/virutil.h

index 854b494890..da267c6446 100644

--- a/src/util/virutil.h

+++ b/src/util/virutil.h

@@ -120,10 +120,8 @@ int virGetDeviceID(const char *path,

                    int *maj,

                    int *min) G_GNUC_NO_INLINE;

 int virSetDeviceUnprivSGIO(const char *path,

-                           const char *sysfs_dir,

                            int unpriv_sgio);

 int virGetDeviceUnprivSGIO(const char *path,

-                           const char *sysfs_dir,

                            int *unpriv_sgio);

 char *virGetUnprivSGIOSysfsPath(const char *path,

                                 const char *sysfs_dir);

-- 

2.32.0