To correctly handle errors from readdir() you must set 'errno'
to zero before invoking it & check its value afterwards to
distinguish error from EOF.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The current code for setting up loop devices to LXC disks first
does a switch() based on the disk format, then looks at the
disk driver name. Reverse this so it first looks at the driver
name, and then the disk format. This is more useful since the
list of supported disk formats depends on what driver is used.

The code for setting loop devices for LXC fs entries also needs
to have the same logic added, now the XML schema supports this.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Extend the <driver> element in filesystem devices to
allow a storage format to be set. The new attribute
uses 'format' to reflect the storage format. This is
different from the <driver> element in disk devices
which use 'type' to reflect the storage format. This
is because the 'type' attribute on filesystem devices
is already used for the driver backend, for which the
disk devices use the 'name' attribute. Arggggh.

Anyway for disks we have

   <driver name="qemu" type="raw"/>

And for filesystems this change means we now have

   <driver type="loop" format="raw"/>
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

After introducing AppArmorSetSecuritySCSILabel() in 2691cd5f
we are using virSCSIDevicePtr type without proper include.

To not introduce more redundant code, helpers are added for
both "selinux", "dac", and "apparmor" backends.
Signed-off-by: NHan Cheng <hanc.fnst@cn.fujitsu.com>
Signed-off-by: NOsier Yang <jyang@redhat>

v2.5 - v3:
  * Splitted from 8/10 of v2.5
  * Don't forget the other backends (DAC, and apparmor)

This adds the scsi-generic device into the device controller's
whitelist, so that it's allowed to used by the qemu process.
Signed-off-by: NHan Cheng <hanc.fnst@cn.fujitsu.com>
Signed-off-by: NOsier Yang <jyang@redhat.com>

Describe the new cgroups layout, how to customize placement
of guests and what virsh commands are used to access the
parameters.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Since it's generic enough to be used by other types in future, I
put it in <hostdev> as sub-element, though now it's only used by
scsi host device.

Except the scsi host device's controller is "lsilogic", mapping
between the libvirt attributes and scsi-generic properties is:

  libvirt     qemu
-----------------------------------------
  controller  bus ($libvirt_controller.0)
  bus         channel
  target      scsi-id
  unit        lun

For scsi host device with "lsilogic" controller, the mapping is:
('target (libvirt)' must be 0, as it's not used; 'unit (libvirt)
must <= 7).

  libvirt            qemu
----------------------------------------------------------
  controller && bus  bus ($libvirt_controller.$libvirt_bus)
  unit               scsi-id

It's not good to hardcode/hard-check limits of these attributes,
and even worse, these limits are not documented, one has to find
out by either testing or reading the qemu code, I'm looking forward
to qemu expose limits like these one day). For example, exposing
"max_target", "max_lun" for megasas:

static const struct SCSIBusInfo megasas_scsi_info = {
    .tcq = true,
    .max_target = MFI_MAX_LD,
    .max_lun = 255,

    .transfer_data = megasas_xfer_complete,
    .get_sg_list = megasas_get_sg_list,
    .complete = megasas_command_complete,
    .cancel = megasas_command_cancel,
};

Example of the qemu command line (lsilogic controller):

  -drive file=/dev/sg2,if=none,id=drive-hostdev-scsi_host7-0-0-0 \
  -device scsi-generic,bus=scsi0.0,scsi-id=8,\
  drive=drive-hostdev-scsi_host7-0-0-0,id=hostdev-scsi_host7-0-0-0

Example of the qemu command line (virtio-scsi controller):

  -drive file=/dev/sg2,if=none,id=drive-hostdev-scsi_host7-0-0-0 \
  -device scsi-generic,bus=scsi0.0,channel=0,scsi-id=128,lun=128,\
  drive=drive-hostdev-scsi_host7-0-0-0,id=hostdev-scsi_host7-0-0-0
Signed-off-by: NHan Cheng <hanc.fnst@cn.fujitsu.com>
Signed-off-by: NOsier Yang <jyang@redhat.com>

This patch adds util functions for scsi hostdev.
Signed-off-by: NHan Cheng <hanc.fnst@cn.fujitsu.com>
Signed-off-by: NOsier Yang <jyang@redhat.com>

Adding two cap flags for scsi-generic:
  QEMU_CAPS_SCSI_GENERIC
  QEMU_CAPS_SCSI_GENERIC_BOOTINDEX
Signed-off-by: NHan Cheng <hanc.fnst@cn.fujitsu.com>
Signed-off-by: NOsier Yang <jyang@redhat.com>

All of these macros are now unused, so remove.

An example of the scsi hostdev XML:

    <hostdev mode='subsystem' type='scsi'>
      <source>
        <adapter name='scsi_host0'/>
        <address bus='0' target='0' unit='0'/>
      </source>
      <address type='drive' controller='0' bus='0' target='4' unit='8'/>
    </hostdev>

Controller is implicitly added for scsi hostdev, though the scsi
controller's model defaults to "lsilogic", which might be not what
the user wants (same problem exists for virtio-scsi disk). It's
the existing problem, will be addressed later.

The device address must be specified manually. Later patch will let
libvirt generate it automatically.

This only introduces the generic XMLs for scsi hostdev, later patches
will add other elements, e.g. <readonly>, <shareable>.
Signed-off-by: NHan Cheng <hanc.fnst@cn.fujitsu.com>
Signed-off-by: NOsier Yang <jyang@redhat.com>

Since the NPIV machine is not easy to get, it's very likely to
introduce regressions when doing changes on the existing code.
This patch dumps part of the sysfs files (the necessary ones)
of fc_host as test input data, to test the related util functions.
It could be extended for more fc_host related testing in future.

The helper works for default sysfs_prefix, but for user specified
prefix, it doesn't work. (Detected when writing test cases. A later
patch will add the test cases for fc_host).

The returned result is something like "host5" acutally.

Function name with "aIsB" generally means its return value is
in Bi-state (true/false).

In case of the caller can pass a "prefix" (or "sysfs_prefix")
without the trailing slash, and Unix-Like system always eats
up the redundant "slash" in the filepath, let's add it explicitly.

Which refactored the old code, and introduced new helper
virIsCapableVport, but the path for checking with access() is not
correctly constructed.

Introduced by commit 244ce462, which refactored the helper for wwn
reading, however, it forgot to change the old "strndup" and "sizeof(buf)",
"sizeof(buf)" operates on the fixed length array ("buf") in the old code,
but now "buf" is a pointer.

Before the fix:

% virsh nodedev-dumpxml scsi_host5
<device>
  <name>scsi_host5</name>
  <parent>pci_0000_04_00_1</parent>
  <capability type='scsi_host'>
    <host>5</host>
    <capability type='fc_host'>
      <wwnn>2001001b</wwnn>
      <wwpn>2101001b</wwpn>
      <fabric_wwn>2001000d</fabric_wwn>
    </capability>
  </capability>
</device>

With the fix:

% virsh nodedev-dumpxml scsi_host5
<device>
  <name>scsi_host5</name>
  <parent>pci_0000_04_00_1</parent>
  <capability type='scsi_host'>
    <host>5</host>
    <capability type='fc_host'>
      <wwnn>0x2001001b32a9da4e</wwnn>
      <wwpn>0x2101001b32a9da4e</wwpn>
      <fabric_wwn>0x2001000dec9877c1</fabric_wwn>
    </capability>
  </capability>
</device>

Commit bfe7721d introduced a regression, but only on platforms
like FreeBSD that lack posix_fallocate and where mmap serves as
a nice fallback for safezero.

util/virfile.c: In function 'safezero':
util/virfile.c:837: error: 'PROT_READ' undeclared (first use in this function)

* src/util/virutil.c (includes): Move use of <sys/mman.h>...
* src/util/virfile.c (includes): ...to the file that uses mmap.
Signed-off-by: NEric Blake <eblake@redhat.com>

This picks up a fix for a syntax-check weakness mentioned here:
https://www.redhat.com/archives/libvir-list/2013-May/msg00811.html

* .gnulib: Update to latest, for maint.mk improvement.
Signed-off-by: NEric Blake <eblake@redhat.com>

Update the hellolibvirt example program to demonstrate use of
the virGetLastErrorMessage() API for quick error reporting
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Add a test case which exercises the virFDStreamOpenFile
and virFDStreamCreateFile methods. Ensure that both the
synchronous and non-blocking iohelper code paths work.
This validates the regression recently fixed which
broke reading in non-blocking mode
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Currently the fdstream function hardcodes the location
of the iohelper to LIBEXECDIR "/libvirt_iohelper". This
is not convenient when trying to write test cases which
use this code. Add a virFDStreamSetIOHelper method to
allow the test cases to point to the location of the
un-installed iohelper binary.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Apps using libvirt will often have code like

   if (virXXXX() < 0) {
      virErrorPtr err = virGetLastError();
      fprintf(stderr, "Something failed: %s\n",
              err && err->message ? err->message :
              "unknown error");
      return -1;
   }

Checking for a NULL error object or message leads to very
verbose code. A virGetLastErrorMessage() helper from libvirt
can simplify this to

   if (virXXXX() < 0) {
      fprintf(stderr, "Something failed: %s\n",
              virGetLastErrorMessage());
      return -1;
   }
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

In b2878ed8 we added the O_NOCTTY
flag when opening files in the stream code. Unfortunately a later
piece of code was comparing the flags == O_RDONLY, without masking
out the non-access mode flags. This broke the iohelper when used
with streams for read, since it caused us to attach the stream
output pipe to the stream input FD instead of output FD :-(
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

It is possible to build a kernel without swap cgroup controls
present. This causes a fatal error when querying memory
parameters. Treat missing swap controls as meaning "unlimited".
The fatal error remains if the user tries to actually change
the limit.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

- provide virNetDevSetMAC() implementation based on SIOCSIFLLADDR
  ioctl.
- adjust virNetDevExists() to check for ENXIO error because
  FreeBSD throws it when device doesn't exist
Signed-off-by: NEric Blake <eblake@redhat.com>

These all existed before virfile.c was created, and for some reason
weren't moved.

This is mostly straightfoward, although the syntax rule prohibiting
write() had to be changed to have an exception for virfile.c instead
of virutil.c.

This movement pointed out that there is a function called
virBuildPath(), and another almost identical function called
virFileBuildPath(). They really should be a single function, which
I'll take care of as soon as I figure out what the arglist should look
like.

This resolves:

     https://bugzilla.redhat.com/show_bug.cgi?id=851411
     https://bugzilla.redhat.com/show_bug.cgi?id=955500

The first problem was that virFileOpenAs was returning fd (-1) in one
of the error cases rather than ret (-errno), so the caller thought
that the error was EPERM rather than ENOENT.

The second problem was that some log messages in the general purpose
qemuOpenFile() function would always say "Failed to create" even if
the caller hadn't included O_CREAT (i.e. they were trying to open an
existing file).

This fixes virFileOpenAs to jump down to the error return (which
returns ret instead of fd) in the previously mentioned incorrect
failure case of virFileOpenAs(), removes all error logging from
virFileOpenAs() (since the callers report it), and modifies
qemuOpenFile to appropriately use "open" or "create" in its log
messages.

NB: I seriously considered removing logging from all callers of
virFileOpenAs(), but there is at least one case where the caller
doesn't want virFileOpenAs() to log any errors, because it's just
going to try again (qemuOpenFile()). We can't simply make a silent
variation of virFileOpenAs() though, because qemuOpenFile() can't make
the decision about whether or not it wants to retry until after
virFileOpenAs() has already returned an error code.

Likewise, I also considered changing virFileOpenAs() to return -1 with
errno set on return, and may still do that, but only as a separate
patch, as it obscures the intent of this patch too much.

The function takes pool name as argument. However,
it is not acceptable for it to be NULL. Hence, we
should check it and report error in case it is.

Added error checking to virEventRegisterDefaultImpl call for consistency.