Make functions w/o a prototype static and remove redundant
declaration of xs_fire_next_watch().
Signed-off-by: Christoph Egger <Christoph.Egger@amd.com>
I originally had just changed the NEWINTF ioctl to send over 48-bits
of information, which works on 64-bit but not on 32-bit (since the arg
is an unsigned long). Additionally, the previous changes would break
an older userland against a new kernel. For that reason, introduce a
new ioctl (NEWINTF_EXT) that fixes both of these problems. This is
the dom0 userland side.
Signed-off-by: Chris Lalancette <clalance@redhat.com>
tapdisk, part of blktap, links against libcrypto. tapdisk includes
GPLv2 (tapaio.c) and other licensed code (block-qcow.c). The license
of OpenSSL is considered incompatible with the GPL by many
people. This patch changes them to link against libgcrypt, which is
LGPL.
Signed-off-by: Bastian Blank <waldi@debian.org>
When a domain wants to use a tap:ioemu disk but has no device model,
start a tapdisk-ioemu instance as provider. Also, move the creation
and removal of communication pipes to xend so that qemu-dm doesn't
need the unwanted SIGHUP handler anymore.
Signed-off-by: Kevin Wolf <kwolf@suse.de>
When a domain wants to use a tap:ioemu disk but has no device model,
start a tapdisk-ioemu instance as provider. Also, move the creation
and removal of communication pipes to xend so that qemu-dm doesn't
need the unwanted SIGHUP handler anymore.
Signed-off-by: Kevin Wolf <kwolf@suse.de>
Fix tapdisk to use big endian L1 tables as used by qemu/ioemu. Old
tapdisk images with native endianess are automagically converted to
big endian when the image file is opened for the first time.
Signed-off-by: Kevin Wolf <kwolf@suse.de>
With some combinations of compiler flags (no optimization, -Werror),
the compiler may complain that the function doesn't have a return
statement (even if the function actually just never returns), reported
as bug 1128. This adds a dummy return statement.
Signed-off-by: Samuel Thibault <samuel.thibault@eu.citrix.com>
Add support for a tap:ioemu pseudo driver. Devices using this driver
won't use tapdisk (containing the code duplication) any more, but will
connect to the qemu-dm of the domain. In this way no working
configuration should be broken right now as you can still choose to
use the tapdisk drivers.
Signed-off-by: Kevin Wolf <kwolf@suse.de>
With my qcow2 patch to blktap I contributed a bit to the mess, so here
an attempt to clean up and remove at least some of the code
duplication in the functions dealing with aio operations.
Signed-off-by: Kevin Wolf <kwolf@suse.de>
This patch adds support for the qcow2 image format to blktap. It
consists mostly of qemu code, adapted to the blktap interfaces.
Snapshots and compressed images are supported.
The qcow2 driver may be used by either specifying tap:qcow2 or by
using tap:qcow which will detect that you have a version 2 image and
will call the qcow2 driver.
Signed-off-by: Kevin Wolf <kwolf@suse.de>
mb/rmb/wmb. Instead add a xen_ prefix. Modify Xen's public headers to
expect the prefixed names instead of bare mb/rmb/wmb, but gate this
expectation on a bump of __XEN_INTERFACE_VERSION__.
Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
In tools/blktap/drivers/tapaio.c there is a call to read(2) whose
return value is not checked. The attached patch attempts to do
something vaguely sensible in cases of error.
Fully comprehensive error handling in this area would be quite tough
to introduce now but at least with this change when things go wrong
you stand a chance of getting some information about what happened.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Attached patch removes unused linux specific headers
and makes bswap.h ready for BSD support.
This is first step for BSD support in blktap. More to come.
No functional change.
Signed-off-by: Christoph Egger <Christoph.Egger@amd.com>
The blktapctrl process is responsible for spawning individual tapdisk
processes. It does this using the 'system' method, but unfortunately
none of its file descriptors have the close-on-exec flag set. The
parent blktapctl process opens a couple of unix domain sockets
per-tapdisk it spawns. So the first tapdisk get 2 FDs leaked to it,
the second gets 4 FDs leaked to it, the 3rd gets 6 and so on. The use
of 'system' also unneccessarily invokes the shell.
Replace system with fork/execvp, and explicitly close all file handles
up to _SC_OPEN_MAX.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Fixes correctness issues with xenstored and gcc-4.2.
Original patch by Charles Coffing <ccoffing@novell.com>
Signed-off-by: Keir Fraser <keir@xensource.com>
blktap requires a xen specific kernel AIO ABI which has been vetoed by
upstream in favour of another approach. Rather than include this ABI,
Fedora has been carrying a patch which makes tap:aio use a thread to
poll for aio events and notify the main thread via a pipe.
The upstream approach of allowing io_getevents() poll normal file
descriptors via epoll is still progressing:
http://lkml.org/lkml/2007/1/3/16
but when that does make it upstream, blktap will require significant
re-working to use that approach.
In the meantime, here's a patch which uses the poll-in-a-thread
approach only if AIO poll support isn't available. It also hides the
details behind a simple abstraction and makes both tap:aio and
tap:qcow use it.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Note that some of the existing error checking for asprintf was wrong
for Linux. asprintf in glibc returns -1 on error, but leaves the
pointer uninitialized. Only the BSDs zero out the pointer on error.
Also, while fixing these warnings I saw several error paths that were
incorrect. This patch minimally fixes the warn_unused_result; more
complete error path cleanup will be a later patch.
Signed-off-by: Charles Coffing <ccoffing@novell.com>
The only non-obvious change here is in tools/xenfb/Makefile. This now picks up
the headers it requires via the copy in tools/libxc.
Signed-off-by: Ian Campbell <ian.campbell@xensource.com>
When compiling the various blktap drivers with warnings cranked up, I
get errors that return values are not checked.
Signed-off-by: Charles Coffing <ccoffing@novell.com>
blktapctrl already prints out exits reasons for all goto's to
open_failed except of not finding a device number for blktap0
This patch adds just that message so the user will get more info than
just "Unable to start blktapctrl"
Common source of this issue is that blktap is missing/failed to
load/...
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
In blktap's qcow we need split up read/write requests if the requests
span multiple clusters. However, with our MAX_AIO_REQUESTS define we
assume that there is only ever a single aio request per tapdisk
request and under heavy i/o we can run out of room causing us to
cancel requests.
Dynamically allocate (based on cluster_bits) the various io request
queues the driver maintains.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
qcow2raw would hang the conversion just short of 100%, because the
final write queue was never being submitted. If a blktap drivers read
synchronously, then "submit_events" and "complete" variables are
checked before getting set, so the fact that reads have finished is
not noticed, so the final write queue was never submitted.
Note that I have also removed the variables write_complete and
read_complete. They were unused, and they were also not set correctly
in the synchronous case.
Signed-off-by: Charles Coffing <ccoffing@novell.com>
Keir Fraser
kfraser@localhost.localdomain
Keir Fraser
Ian Campbell
Brendan Cully
Jake Wires