Commit Graph

218 Commits

Author SHA1 Message Date
Ján Tomko
f61770a169 virStorageBackendWipeLocal: remove bytes_wiped argument
It is not used by the caller.
2015-12-17 12:44:35 +01:00
Ján Tomko
c3f7371c5e storage: drop 'Extent' from virStorageBackendWipeExtentLocal
The only caller always passes 0 for the extent start.
Drop the 'extent_start' parameter, as well as the mention of extents
from the function name.

Change off_t extent_length to unsigned long long wipe_len, as well as the
'remain' variable.
2015-12-17 12:44:35 +01:00
Ján Tomko
4bccdf0ceb storage: move buffer allocation inside virStorageBackendWipeExtentLocal
We do not need to pass a zero-filled buffer as an argument,
the function can allocate its own.
2015-12-17 12:44:35 +01:00
Ján Tomko
09cbfc0481 storage: fix return values of virStorageBackendWipeExtentLocal
Return -1:
* on all failures of fdatasync. Instead of propagating -errno
  all the way up to the virStorageVolWipe API, which is documented
  to return 0 or -1.
* after a partial wipe. If safewrite failed, we would re-use the
  non-negative return value of lseek (which should be 0 in this case,
  because that's the only offset we seek to).
2015-12-17 12:44:02 +01:00
John Ferlan
b3df72c4dd storage: Add debug message
I found this useful while processing a volume that wouldn't end up
showing up in the resulting list of block volumes. In this case, the
partition type wasn't found in the disk_types table.
2015-12-09 16:31:14 -05:00
John Ferlan
1bc84b0a08 storage: Handle readflags errors
Similar to the openflags VIR_STORAGE_VOL_OPEN_NOERROR processing, if some
read processing operation fails, check the readflags for the corresponding
error flag being set. If so, rather then causing an error - use VIR_WARN
to flag the error, but return -2 which some callers can use to perform
specific actions. Use a new VIR_STORAGE_VOL_READ_NOERROR flag in a new
VolReadErrorMode enum.
2015-12-09 16:31:14 -05:00
John Ferlan
1edfce9b18 storage: Set ret = -1 on failures in virStorageBackendUpdateVolTargetInfo
While processing the volume for lseek, virFileReadHeaderFD, and
virStorageFileGetMetadataFromBuf - failure would cause an error,
but ret would not be set. That would result in an error message being
sent, but successful status being returned.
2015-12-09 16:31:14 -05:00
John Ferlan
af4028dccd storage: Add comments for backend APIs
Just so it's clearer what to expect upon input and what types of return
values could be generated.  These were loosely copied from existing
virStorageBackendUpdateVolTargetInfoFD.
2015-12-09 16:31:14 -05:00
John Ferlan
22346003dc storage: Add readflags for backend error processing
Similar to the openflags which allow VIR_STORAGE_VOL_OPEN_NOERROR to be
passed to avoid open errors, add a 'readflags' variable so that in the
future read failures could also be ignored.
2015-12-09 16:31:14 -05:00
John Ferlan
5e3ad0b775 storage: Change virStorageBackendVolOpen to use virFileOpenAs
https://bugzilla.redhat.com/show_bug.cgi?id=1282288

Rather than using just open on the path, allow for the possibility that
the path to be opened resides on an NFS root-squash target and was created
under a different uid/gid.

Without using virFileOpenAs an attempt to get the volume size data may fail
if the current user doesn't have permissions to read the volume, such as
would be the case if mode wasn't supplied in the volume XML and the default
VIR_STORAGE_DEFAULT_VOL_PERM_MODE (e.g. 0600) was used. Under this scenario
the owner/group is not root:root, thus this path run under root would fail
to open/read the volume.

NB: The virFileOpenAs code using OPEN_FORK will only work when the failure
is not EACESS/EPERM and the path resolves to a shared file system.
2015-11-20 17:07:13 -05:00
John Ferlan
ce6506b0bc storage: Really fix setting mode for backend exec in NFS root-squash env
https://bugzilla.redhat.com/show_bug.cgi?id=1282288

Although commit id '77346f27' resolves part of the problem regarding creating
a qemu-img image in an NFS root-squash environment, it really didn't fix the
entire problem. Unfortunately it only masked the problem. It seems qemu-img
must open/create the image using 0644, which if used by target.perms would
result in the chmod not being called since the mode desired and set match.

Although qemu-img could conceivably ignore the mode when creating, libvirt
has more knowledge of the environment and can make the adjustment to the
mode far more easily by using virFileOpenAs with VIR_FILE_OPEN_FORCE_MODE.
If that's successful, then we know on return the file will have the right
owner and mode, so we can declare success
2015-11-20 17:07:13 -05:00
John Ferlan
2265e7dd14 storage: Cleanup failures in virStorageBackendCreateRaw
After successfully returning from virFileOpenAs, if subsequent calls fail,
then we need to remove the file since our caller expects that failures after
creation will remove the created file.
2015-11-04 07:21:11 -05:00
John Ferlan
9345c2bfcf storage: Cleanup failures virStorageBackendCreateExecCommand
After a successful qemu-img/qcow-create of the backing file, if we
fail to stat the file, change it owner/group, or mode, then the
cleanup path should remove the file.
2015-11-04 07:21:11 -05:00
John Ferlan
77346f2787 storage: Fix setting mode in virStorageBackendCreateExecCommand
Currently the code does not handle the NFS root squash environment
properly since if the file gets created, then the subsequent chmod
will fail in a root squash environment where we're creating a file
in the pool with qemu tools, such as seen via:

   $ virsh vol-create-from $pool $file.xml file.img --inputpool $pool

assuming $file.xml is creating a file of "<format type='qcow2'"> from
an existing file.img in the pool of "<format type='raw'>".

This patch will utilize the virCommandSetUmask when creating the file
in the NETFS pool. The virCommandSetUmask API was added in commit id
'0e1a1a8c4', which was after the original code was developed in commit
id 'e1f27784' to attempt to handle the root squash environment.

Also, rather than blindly attempting to chmod, check to see if the
st_mode bits from the stat match what we're trying to set and only
make the chmod if they don't.

Also, a slight adjustment to the fallback algorithm to move the
virCommandSetUID/virCommandSetGID inside the if (!filecreated) since
they're only useful if we need to attempt to create the file again.
2015-11-04 07:21:11 -05:00
John Ferlan
1059c48180 storage: Rework error paths for virStorageBackendCreateExecCommand
Rework the code in order to use the "ret = -1;" and goto cleanup;
coding style.

Signed-off-by: John Ferlan <jferlan@redhat.com>
2015-10-13 18:03:55 -04:00
John Ferlan
4ee3d4c285 storage: Perform some cleanup of calls
Cleanup calls to virStorageBackendCopyToFD a bit.

Signed-off-by: John Ferlan <jferlan@redhat.com>
2015-10-08 07:06:51 -04:00
John Ferlan
691dd388ae storage: Correct the 'mode' check
Commit id '7c2d65dde2' changed the default value of mode to be -1 if not
supplied in the XML, which should cause creation of the volume using the
default mode of VIR_STORAGE_DEFAULT_VOL_PERM_MODE; however, the check
made was whether mode was '0' or not to use default or provided value.

This patch fixes the issue to check if the 'mode' was provided in the XML
and use that value.
2015-09-02 08:59:53 -04:00
Guido Günther
269d39afe5 storage: only run safezero if allocation is > 0
While a zero allocation in safezero should be fine it isn't when we use
posix_fallocate which returns EINVAL on a zero allocation.

While we could skip the zero allocation in safezero_posix_fallocate it's
an optimization to do it for all allocations.

This fixes vm installation via virtinst for me which otherwise aborts
like:

   Starting install...
   Retrieving file linux...               | 5.9 MB     00:01 ...
   Retrieving file initrd.gz...           |  29 MB     00:07 ...
   ERROR    Couldn't create storage volume 'virtinst-linux.sBgds4': 'cannot fill file '/var/lib/libvirt/boot/virtinst-linux.sBgds4': Invalid argument'

The error was introduced by e30297b0 as spotted by Chunyan Liu
2015-08-24 13:51:44 +02:00
Chris J Arges
c6eea54008 storage: allow zero capacity with non-backing file to be created
In commit 155ca616e, a change was introduced that no longer allowed defining
volumes via XML with a capacity of '0'. Because we check for info.size_arg
to be non-zero, this use-case fails. This patch allows info.size_arg to be
zero if no backing store is specified.

Signed-off-by: Chris J Arges <chris.j.arges@canonical.com>
2015-07-24 11:22:20 -04:00
Prerna Saxena
dd519a294b Fix cloning of raw, sparse volumes
When virsh vol-clone is attempted on a raw file where capacity > allocation,
the resulting cloned volume has a size that matches the virtual-size of
the parent; in place of matching its actual, disk size.
This patch fixes the cloned disk to have same _allocated_size_ as
the parent file from which it was cloned.

Ref: http://www.redhat.com/archives/libvir-list/2015-May/msg00050.html

Also fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1130739

Signed-off-by: Prerna Saxena <prerna@linux.vnet.ibm.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
2015-07-10 08:54:10 +02:00
Ján Tomko
e30297b096 Rewrite allocation tracking when cloning volumes
Instead of storing the remaining bytes, store the position of the first
unallocated byte. This will allow changing the amount of bytes copied
by virStorageBackendCopyToFD without changing the safezero call.

No functional impact.
2015-07-10 08:53:26 +02:00
Cole Robinson
7c2d65dde2 storage: conf: Don't set any default <mode> in the XML
The XML parser sets a default <mode> if none is explicitly passed in.
This is then used at pool/vol creation time, and unconditionally reported
in the XML.

The problem with this approach is that it's impossible for other code
to determine if the user explicitly requested a storage mode. There
are some cases where we want to make this distinction, but we currently
can't.

Handle <mode> parsing like we handle <owner>/<group>: if no value is
passed in, set it to -1, and adjust the internal consumers to handle
it.
2015-05-25 20:52:55 -04:00
Cole Robinson
56476f6a2d storage: fs: Ignore volumes that fail to open with EACCESS/EPERM
Trying to use qemu:///session to create a storage pool pointing at
/tmp will usually fail with something like:

$ virsh pool-start tmp
error: Failed to start pool tmp
error: cannot open volume '/tmp/systemd-private-c38cf0418d7a4734a66a8175996c384f-colord.service-kEyiTA': Permission denied

If any volume in an FS pool can't be opened by the daemon, the refresh
fails, and the pool can't be used.

This causes pain for virt-install/virt-manager though. Imaging a user
downloads a disk image to /tmp. virt-manager wants to import /tmp as
a storage pool, so we can detect what disk format it is, and set the
XML correctly. However this case will likely fail as explained above.

Change the logic here to skip volumes that fail to open. This could
conceivably cause user complaints along the lines of 'why doesn't
libvirt show $ROOT-OWNED-VOLUME-FOO', but figuring that currently
the pool won't even startup, I don't think there are any current
users that care about that case.

https://bugzilla.redhat.com/show_bug.cgi?id=1103308
2015-04-28 09:42:19 -04:00
John Ferlan
9e5e1ca144 storage: Fix check for stable path check
Fix the if (!STRPREFIX(path, "/dev")) to be if (!STRPREFIX(path, "/dev/"))
to ensure a path such as "/device" isn't declared stable.
2015-04-21 06:08:56 -04:00
John Ferlan
9126161d0b storage: Split out the stable path check
For virStorageBackendStablePath, in order to make decisions in other code
split out the checks regarding whether the pool's target is empty, using /dev,
using /dev/, or doesn't start with /dev
2015-04-21 06:08:05 -04:00
Ján Tomko
9146fd7aa9 Remove overengineered loop
Do not loop over enum with one value.
2015-04-13 15:59:20 +02:00
Ján Tomko
fbcf7da95b Introduce struct _virStorageBackendQemuImgInfo
This will contain the data required for creating the qemu-img
command line without having access to the volume definition.
2015-04-13 15:59:20 +02:00
Ján Tomko
a832735df9 Rename virStorageBackendCreateQemuImgCmd
Add FromVol at the end. This function will create the qemu-img
command line from volume definitions and check them.
2015-04-13 15:59:20 +02:00
Ján Tomko
22fd3ac38f Introduce virBitmapIsBitSet
A helper that never returns an error and treats bits out of bitmap range
as false.

Use it everywhere we use ignore_value on virBitmapGetBit, or loop over
the bitmap size.
2015-03-13 15:31:33 +01:00
Ján Tomko
155ca616eb Allow creating volumes with a backing store but no capacity
The tool creating the image can get the capacity from the backing
storage. Just refresh the volume afterwards.

https://bugzilla.redhat.com/show_bug.cgi?id=958510
2015-03-02 08:07:11 +01:00
Ján Tomko
d3452a3f73 Revert "Restore skipping of setting capacity"
This reverts commit f1856eb622.

Now that we can update capacity from image metadata,
we don't need to skip the update.
2015-03-02 08:07:11 +01:00
Ján Tomko
a760ba3a7f Probe for capacity in virStorageBackendUpdateVolTargetInfo
Instead of just looking at the output of fstat, call
virStorageFileGetMetadata to get the full capacity from
image headers.

Note that the capacity is probed unconditionally. The updateCapacity
bool parameter is ignored and will be removed in the following commit.
2015-03-02 08:07:11 +01:00
John Ferlan
bce671b731 storage: Adjust how to refresh extended partition disk data
During virStorageBackendDiskMakeDataVol processing, if we find an extended
partition, then handle it specially when updating the capacity/allocation
rather than calling virStorageBackendUpdateVolInfo.

As it turns out, once a logical partition exists, any attempt to refresh
the pool or after libvirtd restart/reload will result in a failure to open
the extended partition device resulting in the inability to start the pool.
The downside to this is we will lose the <permissions> and <timestamps> for
the extended partition upon subsequent restart, refresh, reload since the
stat() in virStorageBackendUpdateVolTargetInfoFD will not be called. However,
since it's really only a container and shouldn't directly be used for
storage that seems reasonable.

Therefore, only use the existing code that already had a comment about
getting the allocation wrong for extended partitions for just the setting
of the extended partition data.
2015-01-28 17:28:03 -05:00
Chen Hanxiao
95da191376 storage: add a flag to clone files on btrfs
When creating a RAW file, we don't take advantage
of clone of btrfs.

Add a VIR_STORAGE_VOL_CREATE_REFLINK flag to request
a reflink copy.

Signed-off-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
2015-01-27 13:41:14 +01:00
Chen Hanxiao
466b29c8c3 storage: introduce btrfsCloneFile() for COW copy
Add a wrapper for BTRFS_IOC_CLONE ioctl.

Signed-off-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
2015-01-27 13:24:10 +01:00
Ján Tomko
1390c26847 safezero: fall back to writing zeroes even when resizing
Remove the resize flag and use the same code path for all callers.
This flag was added by commit 18f0316 to allow virStorageFileResize
use 'safezero' while preserving the behavior.

Explicitly return -2 when a fallback to a different method should
be done, to make the code path more obvious.

Fail immediately when ftruncate fails in the mmap method,
as we did before commit 18f0316.
2015-01-09 13:48:23 +01:00
John Ferlan
18f03166fd virstoragefile: Have virStorageFileResize use safezero
Currently virStorageFileResize() function uses build conditionals to
choose either the posix_fallocate() or syscall(SYS_fallocate) with no
fallback in order to preallocate the space in the newly resized file.

Since the safezero code has a similar set of conditionals modify the
resize and safezero code in order to allow the resize logic to make use
of safezero to unify the look/feel of the code paths.

Add a new boolean (resize) to safezero() to make the optional decision
whether to try syscall(SYS_fallocate) if the posix_fallocate fails because
HAVE_POSIX_FALLOCATE is not defined (eg, return -1 and errno == 0).

Create a local safezero_sys_fallocate in order to handle the resize
code paths that support that.  If not present, the set errno = ENOSYS
in order to allow the caller to handle the failure scenarios.

Signed-off-by: John Ferlan <jferlan@redhat.com>
2014-12-16 13:11:35 -05:00
John Ferlan
a0b13d35e7 Replace virSecretFree with virObjectUnref
Since virSecretFree will call virObjectUnref anyway, let's just use that
directly so as to avoid the possibility that we inadvertently clear out
a pending error message when using the public API.
2014-12-02 11:03:41 -05:00
Martin Kletzander
e7a1da8aeb Remove unnecessary curly brackets in src/storage/
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2014-11-14 17:13:01 +01:00
Roman Bogorodskiy
f5b4c14155 fdstream: introduce virFDStreamOpenBlockDevice
virStorageBackendVolDownloadLocal and virStorageBackendVolUploadLocal
use virFDStreamOpenFile function to work with the volume fd.

virFDStreamOpenFile calls virFDStreamOpenFileInternal that implements
handling of the non-blocking I/O. If a file is not a character device and
not a fifo, it uses libvirt_iohelper.

On FreeBSD, it doesn't work as expected because disk devices (including
ZFS volumes) are exposed as character devices, and ZFS volumes do not
support open(2) with O_NONBLOCK.

To overcome this, introduce a forceIOHelper flag to
virFDStreamOpenFileInternal that forces using libvirt_iohelper. And
introduce virFDStreamOpenBlockDevice that calls
virFDStreamOpenFileInternal with the forceIOHelper set to true.
2014-08-25 10:46:13 +04:00
Eric Blake
b50c8603a2 maint: improve syntax check for space around =
Laine Stump noted on IRC that syntax check wasn't flagging his
typo of 'i= 0'.  This fixes it.

* build-aux/bracket-spacing.pl: Tighten 'space around =' rule.
* src/storage/storage_backend.c
(virStorageBackendCreateExecCommand): Fix offenders.
* src/util/virnuma.c (virNumaGetDistances): Likewise.
* src/vbox/vbox_tmpl.c (vboxDomainSnapshotDeleteMetadataOnly)
(vboxNetworkGetXMLDesc): Likewise.
* src/xenapi/xenapi_driver.c (xenapiDomainLookupByName):
Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-08-12 11:21:17 -06:00
Roman Bogorodskiy
0257d06ba4 storage: ZFS support
Implement ZFS storage backend driver. Currently supported
only on FreeBSD because of ZFS limitations on Linux.

Features supported:

 - pool-start, pool-stop
 - pool-info
 - vol-list
 - vol-create / vol-delete

Pool definition looks like that:

 <pool type='zfs'>
  <name>myzfspool</name>
  <source>
    <name>actualpoolname</name>
  </source>
 </pool>

The 'actualpoolname' value is a name of the pool on the system,
such as shown by 'zpool list' command. Target makes no sense
here because volumes path is always /dev/zvol/$poolname/$volname.

User has to create a pool on his own, this driver doesn't
support pool creation currently.

A volume could be used with Qemu by adding an entry like this:

    <disk type='volume' device='disk'>
      <driver name='qemu' type='raw'/>
      <source pool='myzfspool' volume='vol5'/>
      <target dev='hdc' bus='ide'/>
    </disk>
2014-08-12 19:40:20 +04:00
Ján Tomko
be3cbecd0e Fix a crash when cloning a volume with no backing store
Introduced by commit 15213d1, not yet released.
2014-08-01 15:42:28 +02:00
Ján Tomko
490bf29d50 Log an error when we fail to set the COW attribute
Coverity complains about the return value of ioctl not being checked.

Even though we carry on when this fails (just like qemu-img does),
we can log an error.
2014-07-17 14:32:29 +02:00
Peter Krempa
4d799b65cd storage: wipe: Move helper code into storage backend
The next patch will move the storage volume wiping code into the
individual backends. This patch splits out the common code to wipe a
local volume into a separate backend helper so that the next patch is
simpler.
2014-07-17 10:12:34 +02:00
Chunyan Liu
a9fd30e633 storagevol: add nocow to vol xml
Add 'nocow' to storage volume xml so that user can have an option
to set NOCOW flag to the newly created volume. It's useful on btrfs
file system to enhance performance.

Btrfs has low performance when hosting VM images, even more when the guest
in those VM are also using btrfs as file system. One way to mitigate this
bad performance is to turn off COW attributes on VM files. Generally, there
are two ways to turn off COW on btrfs: a) by mounting fs with nodatacow,
then all newly created files will be NOCOW. b) per file. Add the NOCOW file
attribute. It could only be done to empty or new files.

This patch tries the second way, according to 'nocow' option, it could set
NOCOW flag per file:
for raw file images, handle 'nocow' in libvirt code; for non-raw file images,
pass 'nocow=on' option to qemu-img, and let qemu-img to handle that (requires
qemu-img version >= 2.1).

Signed-off-by: Chunyan Liu <cyliu@suse.com>
2014-07-16 13:35:20 +02:00
Peter Krempa
70120e2f5d storage: fs: Don't fail volume update if backing store isn't accessible
When the backing store of a volume wasn't accessible while updating the
volume definition the call would fail altogether. In cases where we
currently (incorrectly) treat remote backing stores as local one this
might lead to strange errors.

Ignore the opening errors until we figure out how to track proper volume
metadata.
2014-07-16 11:42:52 +02:00
Peter Krempa
15213d1e5d storage: Track backing store of a volume in the target struct
As we have a nested pointer for storing the backing store of a volume
there's no need to store it in a separate struct.
2014-07-16 11:42:51 +02:00
Peter Krempa
c861750ee9 storage: backend: Fix formatting of function arguments 2014-07-16 11:42:51 +02:00
Peter Krempa
589c2ad93f storage: Split out volume upload/download as separate backend function
For non-local storage drivers we can't expect to use the FDStream
backend for up/downloading volumes. Split the code into a separate
backend function so that we can add protocol specific code later.
2014-07-11 09:54:08 +02:00