Commit Graph
18 Commits
Author SHA1 Message Date
Ian Campbell f8b201e720 tools: Update libxl flex outputs to Flex from Jessie.
This is the result of
  $ find -name \*.l -exec touch {} \;
  $ find -name \*.y -exec touch {} \;

and then rebuilding.

This avoids churn on the machine I use for committing which has been
updated, causing flex to go from 2.5.35-10.1 to 2.5.39-8.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2015-10-22 16:05:39 +01:00
Ian Jackson 3bd8559e5e libxl: Renegerate flex output files
Regenerate libxl_*_l.* with flex 2.5.35-10.1 as in current Debian
wheezy.  The differences are trivial: addition of declarations of
xlu__cfg_yyget_column and xlu__cfg_yyset_column, but no code body
changes.

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Release-Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2015-01-06 15:28:17 +00:00
Ian Jackson 4f3c0c93bc libxl: Rerun flex/bison for xl discard support
In 417e6b70 I overlooked the requirement to rerun bison/flex.  Do that
now.  The changes are exactly those which are the result of 417e6b70.

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
2014-05-19 15:17:03 +01:00
Stefano Stabellini 6ec48cf41b libxl: introduce an option for disabling the non-O_DIRECT workaround
Document and implement a new option that permits disk backends which
would otherwise have to avoid O_DIRECT (because of the network memory
lifetime bug) to use it anyway.  This is:
 direct-io-safe   in the xl domain disk config specification
 direct_io_safe   in the libxl disk API
 direct-io-safe   in the backend xenstore interface

Add a reference to xen/include/public/io/blkif.h in
docs/misc/vbd-interface.txt.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Tested-by: Felipe Franciosi <felipe@paradoxo.org>
2014-05-02 17:50:27 +01:00
Daniel De Graaf ef496b81f0 libxl: postpone backend name resolution
This adds a backend_domname field in libxl devices that contain a
backend_domid field, allowing either a domid or a domain name to be
specified in the configuration structures.  The domain name is resolved
into a domain ID in the _setdefault function when adding the device.
This change allows the backend of the block devices to be specified
(which previously required passing the libxl_ctx down into the block
device parser), and will simplify specification of backend domains in
other users of libxl.

The check on run_hotplug_scripts in parse_config_data is removed because
it is a duplicate of the one in libxl__device_nic_setdefault, and is
removed here because it no longer has the resolved domain ID to check.

Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
[ ijc -- reran flex ]
2013-04-17 14:55:36 +01:00
Ian Campbell 6e844c2af0 libxl: support custom block hotplug scripts
These are provided using the "script=" syntax described in
docs/misc/xl-disk-configuration.txt.

The existing hotplug scripts currently conflate two different
concepts, namely that of making a datapath available in the backend
domain (logging into iSCSI LUNs and the like) and that of actually
connecting that datapath to a Xen backend path (e.g. writing
"physical-device" node in xenstore to bring up blkback).

For this reason the script support implemented here is only supported
in conjunction with backendtype=phy.

Eventually we hope to rework the hotplug scripts to separate the to
concepts, but that is not 4.2 material.

In addition there are some other subtleties:

 - Previously in the blktap case we would add "script = .../blktap" to
   the backend flex array, but then jumped to the PHY case which added
   "script = .../block" too. The block one takes precendence since it
   comes second.

   This was, accidentally, correct. The blktap script is for blktap1
   devices and not blktap2 devices. libxl completely manages the
   blktap2 side of things without resorting to hotplug scripts and
   creates a blkback device directly.  Therefore the "block" script is
   always the correct one to call. Custom script are not supported in
   this context.

 - libxl should not write the "physical-device" node. This is the
   responsibility of the block script. Writing the "physical-device"
   node in libxl basically completely short-cuts the standard block
   hotplug script which uses "physical-device" to know if it has run
   already or not.

   In the case of more complex scripts libxl cannot know the right
   value to write here anyway, in particular the device may not exist
   until after the script is called.

   This change has the side effect of re-enabling the checks for
   device sharing aspect of the default block script, which I have tested
   and which now cause libxl to properly abort now that libxl properly
   checks for hotplug script errors.

   There is no sharing check for blktap2 since even if you reuse the
   same vhd the resulting tap device is different. I would have preferred
   to simply write the "physical-device" node for the blktap2 case but
   the hotplug script infrastructure is not currently setup to handle
   LIBXL__DEVICE_KIND_VBD
   devices without a hotplug script (backendtype phy and tap both end
   up as KIND_VBD). Changing this was more surgery than I was happy doing
   for 4.2 and therefore I have simply hardcoded to the block script for
   the LIBXL_DISK_BACKEND_TAP case.

 - libxl__device_disk_set_backend running against a phy device with a
   script cannot stat the device to check its properties since it may
   not exist until the script is run. Therefore I have special cased
   this in disk_try_backend to simply assume that backend == phy is
   always ok if a script was
   configured.  Similarly the other backend types are always rejected
   if a script was configured.

   Note that the reason for implementing the default script behaviour
   in device_disk_add instead of libxl__device_disk_setdefault is
   because we need to be able to tell when the script was
   user-supplied rather than defaulted by libxl in order to correctly
   implement the above. The setdefault function must be idempotent so
   we cannot simply update disk->script.

   I suspect that for 4.3 a script member should be added to
   libxl__device, this would also help in the case above of handling
   devices with no script in a consistent manner. This is not 4.2
   material.

 - When the block script falls through and shells out to a block-$type
   script it used to pass "$node" however the only place this was
   assigned was in the remove+phy case (in which case it contains the
   file:// derived /dev/loopN device), and in that case the script
   exits without falling through to the block-$type case.

   Since libxl never creates a type other than phy this never happens
   in practice anyway and we now call the correct block-$type script
   directly.  But fix it up anyway since it is confusing.

 - The block-nbd and block-enbd scripts which we supply appear to be
   broken WRT the hotplug calling convention, in that they seem to
   expect a command line parameter (perhaps the $node described above)
   rather than reading the appropriate node from xenstore.

   I rather suspect this was broken by 7774:e2e7f47e6f79 in November
   2005. I think it is safe to say no one is using these scripts! I
   haven't fixed this here. It would be good to track down some working
   scripts and either incorproate them or defer to them in their existing
   home (e.g. if they live somewhere useful like the nbd tools
   package).

 - Added a few block script related entries to check-xl-disk-parse
   from http://backdrift.org/xen-block-iscsi-script-with-multipath-support
   and http://lists.linbit.com/pipermail/drbd-user/2008-September/010221.html /
   http://www.drbd.org/users-guide-emb/s-xen-configure-domu.html (and
   snuck in another interesting empty CDROM case)

   This highlighted two bugs in the libxlu disk parser handling of the
   deprecated "<script>:" prefix:

   - It was failing to prefix with "block-" to construct the actual
     script name

   - The regex for matching iscsi or drdb or e?nbd was incorrect

 - Use libxl__abs_path for the nic script too. Just because the
   existing code nearly tricked me into repeating the mistake

I have tested with a custom block script which uses "lvchange -a" to
dynamically add remove the referenced device (simulates iSCSI
login/logout without requiring me to faff around setting up an iSCSI
target). I also tested on a blktap2 system.

I haven't directly tested anything more complex like iscsi: or nbd:
other than what check-xl-disk-parse exercises.

[ Recommit of correct version of 25727:a8d708fcb347, which was mangled
  during commit.  Sorry. -iwj ]

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
2012-08-06 12:28:03 +01:00
Ian Jackson 6390110d62 Backed out changeset a8d708fcb347
25727:a8d708fcb347 was mangled during commit.  Back it out so that we
can commit it properly.

Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
2012-08-06 12:24:46 +01:00
Ian Campbell 1a3e84bd85 libxl: support custom block hotplug scripts
These are provided using the "script=" syntax described in
docs/misc/xl-disk-configuration.txt.

The existing hotplug scripts currently conflate two different
concepts, namely that of making a datapath available in the backend
domain (logging into iSCSI LUNs and the like) and that of actually
connecting that datapath to a Xen backend path (e.g. writing
"physical-device" node in xenstore to bring up blkback).

For this reason the script support implemented here is only supported
in conjunction with backendtype=phy.

Eventually we hope to rework the hotplug scripts to separate the to
concepts, but that is not 4.2 material.

In addition there are some other subtleties:

 - Previously in the blktap case we would add "script = .../blktap" to
   the backend flex array, but then jumped to the PHY case which added
   "script = .../block" too. The block one takes precendence since it
   comes second.

   This was, accidentally, correct. The blktap script is for blktap1
   devices and not blktap2 devices. libxl completely manages the
   blktap2 side of things without resorting to hotplug scripts and
   creates a blkback device directly.  Therefore the "block" script is
   always the correct one to call. Custom script are not supported in
   this context.

 - libxl should not write the "physical-device" node. This is the
   responsibility of the block script. Writing the "physical-device"
   node in libxl basically completely short-cuts the standard block
   hotplug script which uses "physical-device" to know if it has run
   already or not.

   In the case of more complex scripts libxl cannot know the right
   value to write here anyway, in particular the device may not exist
   until after the script is called.

   This change has the side effect of re-enabling the checks for
   device sharing aspect of the default block script, which I have tested
   and which now cause libxl to properly abort now that libxl properly
   checks for hotplug script errors.

   There is no sharing check for blktap2 since even if you reuse the
   same vhd the resulting tap device is different. I would have preferred
   to simply write the "physical-device" node for the blktap2 case but
   the hotplug script infrastructure is not currently setup to handle
   LIBXL__DEVICE_KIND_VBD
   devices without a hotplug script (backendtype phy and tap both end
   up as KIND_VBD). Changing this was more surgery than I was happy doing
   for 4.2 and therefore I have simply hardcoded to the block script for
   the LIBXL_DISK_BACKEND_TAP case.

 - libxl__device_disk_set_backend running against a phy device with a
   script cannot stat the device to check its properties since it may
   not exist until the script is run. Therefore I have special cased
   this in disk_try_backend to simply assume that backend == phy is
   always ok if a script was
   configured.  Similarly the other backend types are always rejected
   if a script was configured.

   Note that the reason for implementing the default script behaviour
   in device_disk_add instead of libxl__device_disk_setdefault is
   because we need to be able to tell when the script was
   user-supplied rather than defaulted by libxl in order to correctly
   implement the above. The setdefault function must be idempotent so
   we cannot simply update disk->script.

   I suspect that for 4.3 a script member should be added to
   libxl__device, this would also help in the case above of handling
   devices with no script in a consistent manner. This is not 4.2
   material.

 - When the block script falls through and shells out to a block-$type
   script it used to pass "$node" however the only place this was
   assigned was in the remove+phy case (in which case it contains the
   file:// derived /dev/loopN device), and in that case the script
   exits without falling through to the block-$type case.

   Since libxl never creates a type other than phy this never happens
   in practice anyway and we now call the correct block-$type script
   directly.  But fix it up anyway since it is confusing.

 - The block-nbd and block-enbd scripts which we supply appear to be
   broken WRT the hotplug calling convention, in that they seem to
   expect a command line parameter (perhaps the $node described above)
   rather than reading the appropriate node from xenstore.

   I rather suspect this was broken by 7774:e2e7f47e6f79 in November
   2005. I think it is safe to say no one is using these scripts! I
   haven't fixed this here. It would be good to track down some working
   scripts and either incorproate them or defer to them in their existing
   home (e.g. if they live somewhere useful like the nbd tools
   package).

 - Added a few block script related entries to check-xl-disk-parse
   from http://backdrift.org/xen-block-iscsi-script-with-multipath-support
   and http://lists.linbit.com/pipermail/drbd-user/2008-September/010221.html /
   http://www.drbd.org/users-guide-emb/s-xen-configure-domu.html (and
   snuck in another interesting empty CDROM case)

   This highlighted two bugs in the libxlu disk parser handling of the
   deprecated "<script>:" prefix:

   - It was failing to prefix with "block-" to construct the actual
     script name

   - The regex for matching iscsi or drdb or e?nbd was incorrect

 - Use libxl__abs_path for the nic script too. Just because the
   existing code nearly tricked me into repeating the mistake

I have tested with a custom block script which uses "lvchange -a" to
dynamically add remove the referenced device (simulates iSCSI
login/logout without requiring me to faff around setting up an iSCSI
target). I also tested on a blktap2 system.

I haven't directly tested anything more complex like iscsi: or nbd:
other than what check-xl-disk-parse exercises.

[ reran flex/bison -iwj ]

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
2012-08-03 11:59:12 +01:00
Ian Jackson a413f5a5f4 xl: support xend empty cdrom device syntax
xend accepts `,hdc:cdrom,r' as an empty CDROM drive.  However this is
not consistent with the existing xl syntax in
docs/misc/xl-disk-configuration.txt which requires `,,hdc:cdrom,r'
(the additional positional paramter is the format).

We fix this by spotting the case specially: when the target is empty
and the format contains a colon, reinterpret the format as
<vdev>:<devtype>.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
2012-07-26 10:35:36 +01:00
Ian Jackson c902f397d6 xl: disk parsing preparation for empty cdrom devices
Prepare the ground for parsing the xend empty cdrom syntax, by
separating out some non-functional changes as this pre-patch:

* Clarify the disk syntax documentation wording to refer to deprecated
  syntaxes too.

* Make DPC in libxlu_disk_l.l useable in the helper functions as well
  as in lexer rules, by providing two definitions, each in force in
  the appropriate parts of the file.

* Break the <vdev>[:<devtype>] parsing out into a helper function,
  `vdev_and_devtype'.

No functional change.

Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
2012-07-26 10:35:36 +01:00
Ian Campbell 7970280833 xl: support empty CDROM devices
The important change here is to xlu_disk_parse to correctly set format == EMPTY
for CDROM devices which are empty. Test cases are added which check for
correctness here.

xend accepts ',hdc:cdrom,r'[0] as an empty CDROM drive however this is not
consistent with the xl syntax in docs/misc/xl-disk-configuration.txt which
requires ',,hdc:cdrom,r' (the additional positional paramter is the format).
I'm not sure if/how this can be fixed. Note that xend does not accept
',,hdc:cdrom,r'

There are several incidental cleanups included the the cdrom-{insert,eject}
commands:
  - add a dry-run mode
  - use the non-deprecated disk specification syntax
  - check for and report errors from libxl_cdrom_insert

[0] http://wiki.xen.org/wiki/CD_Rom_Support_in_Xen

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
2012-07-26 10:35:35 +01:00
Ian Campbell c18ad21eac libxl: fixup incorrect indentation
Several places which were previsously indented using hard tabs are now
incorrectly indented. Fix them up.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
2011-10-12 16:21:32 +01:00
Daniel De Graaf df0c75a05f libxl: correctly parse disk "backendtype" field
The expression for backendtype was missing a comma.

Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
2011-10-10 11:21:51 +01:00
Ian Campbell 321753f1ad libxlu: correctly parse disk "backendtype" field
Currently it tries to parse the value from the full "backendtype=FOO" string
but really it needs to parse from the equals.

Before:
# xl -N block-attach d32-1 backendtype=phy,vdev=xvdb,access=w,target=/dev/VG/debian-x86_32-1b
command line: config parsing error in disk specification: unknown value for backendtype: near `backendtype=phy' in `backendtype=phy,vdev=xvdb,access=w,target=/dev/VG/debian-x86_32-1b'

After [in new syntax, not yet in this tree -iwj]:
# xl -N block-attach d32-1 backendtype=phy,vdev=xvdb,access=w,target=/dev/VG/debian-x86_32-1b
disk: {
    "backend_domid": 0,
    "pdev_path": "/dev/VG/debian-x86_32-1b",
    "vdev": "xvdb",
    "backend": "phy",
    "format": "raw",
    "script": null,
    "removable": 0,
    "readwrite": 1,
    "is_cdrom": 0
}

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
2011-10-06 16:19:03 +01:00
Ian Campbell 2b43aff571 libxl: undo 23728:548b2826293e whitespace cleanup to autogenerated file
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
2011-10-06 16:15:33 +01:00
Wei Liu 1b86994afe libxl: clean up trailing whitespaces in code.
Commit exactly the results of running
   find \! -iname '*.txt' -type f -print0 | xargs -0 perl -p -i.bak -E 's/\s+\n/\n/'

Signed-off-by: Wei Liu <liuw@liuw.name>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed: Ian Jackson <ian.jackson@eu.citrix.com>
2011-07-19 16:02:36 +01:00
Ian Jackson 74f917afa3 libxl: disks: allow specification of "backendtype=phy|tap|qdisk"
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Committed-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
2011-06-28 12:19:15 +01:00
Ian Jackson f7e6e74307 libxl: disks: commit libxlu_disk_l.[ch] flex output
Commit the flex output into revision control, for the benefit of those
without flex or with only very old flex.  This change is split into a
separate patch for ease of review.  Generated with flex 2.5.35-6 on
Debian lenny i386, by running "make" in the libxl directory.  No
manual changes in this commit.

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Committed-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
2011-06-28 12:19:12 +01:00