qemu-ga: ga_open_pidfile(): use qemu_open()

This ensures that O_CLOEXEC is passed to open(), this way the
pid file fd is not leaked to executed processes.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Acked-by: Amos Kong <akong@redhat.com>
Tested-by: Amos Kong <akong@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
qemu-ga: add ga_open_logfile()

This function sets O_CLOEXEC on the log file fd so that it isn't
leaked to executed processes.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Acked-by: Amos Kong <akong@redhat.com>
Tested-by: Amos Kong <akong@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
qemu-ga: Document intentional fall through in channel_event_cb()

For clarity, and to hush up Coverity.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
qemu-ga: Drop pointless lseek() from ga_open_pidfile()

After open(), the file offset is already zero, and neither lockf() nor
ftruncate() change it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
qemu-ga: Plug file descriptor leak on ga_open_pidfile() error path

Spotted by Coverity.  Also document why we keep it open on success.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
qemu-ga: Plug fd leak on ga_channel_listen_accept() error path

Spotted by Coverity.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
qemu-ga: Plug fd leak on ga_channel_open() error paths

Spotted by Coverity.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
qemu-ga: Handle errors uniformely in ga_channel_open()

We detect errors in several places.  One reports with g_error(), which
calls abort(), the others report with g_critical().  Three of them
exit(), three return false.

Always report with g_critical(), and return false.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>

*minor fix-up of commit msg

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
xen_disk: fix memory leak

On ioreq_release the full ioreq was memset to 0, loosing all the data
and memory allocations inside the QEMUIOVector, which leads to a
memory leak. Create a new function to specifically reset ioreq.

Reported-by: Maik Wessler <maik.wessler@yahoo.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
xen_disk: add persistent grant support to xen_disk backend

This protocol extension reuses the same set of grant pages for all
transactions between the front/back drivers, avoiding expensive tlb
flushes, grant table lock contention and switches between userspace
and kernel space. The full description of the protocol can be found in
the public blkif.h header.

http://xenbits.xen.org/gitweb/?p=xen.git;a=blob_plain;f=xen/include/public/io/blkif.h

Speed improvement with 15 guests performing I/O is ~450%.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
xen_disk: implement BLKIF_OP_FLUSH_DISKCACHE, remove BLKIF_OP_WRITE_BARRIER

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
qga: add missing commas in json docs

* qga/qapi-schema.json: Use valid JSON.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
pc87312: Replace register_ioport_*() with MemoryRegion

Prepare an instance_init function for the MemoryRegion init.

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
Tested-by: Hervé Poussineau <hpoussin@reactos.org>
pc87312: Avoid define conflict on mingw32

Mingw32 headers define FAR, causing this warning:
/src/qemu/hw/pc87312.c:38:0: warning: "FAR" redefined [enabled by default]
In file included from /usr/local/lib/gcc/i686-mingw32msvc/4.7.0/../../../../i686-mingw32msvc/include/windows.h:48:0,
                 from /src/qemu/include/sysemu/os-win32.h:29,
                 from /src/qemu/include/qemu-common.h:46,
                 from /src/qemu/include/exec/ioport.h:27,
                 from /src/qemu/hw/isa.h:6,
                 from /src/qemu/hw/pc87312.h:28,
                 from /src/qemu/hw/pc87312.c:26:
/usr/local/lib/gcc/i686-mingw32msvc/4.7.0/../../../../i686-mingw32msvc/include/windef.h:34:0: note: this is the location of the previous definition

Avoid the warning by expanding the macros.

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Acked-by: Hervé Poussineau <hpoussin@reactos.org>
Signed-off-by: Andreas Färber <andreas.faerber@web.de>
qcow2: Fix segfault on zero-length write

One of the recent refactoring patches (commit f50f88b9) didn't take care
to initialise l2meta properly, so with zero-length writes, which don't
even enter the write loop, qemu just segfaulted.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
block: fix initialization in bdrv_io_limits_enable()

bdrv_io_limits_enable() starts a new slice, but does not set io_base
correctly for that slice.

Here is how io_base is used:

    bytes_base  = bs->nr_bytes[is_write] - bs->io_base.bytes[is_write];
    bytes_res   = (unsigned) nb_sectors * BDRV_SECTOR_SIZE;

    if (bytes_base + bytes_res <= bytes_limit) {
        /* no wait */
    } else {
        /* operation needs to be throttled */
    }

As a result, any I/O operations that are triggered between now and
bs->slice_end are incorrectly limited.  If 10 MB of data has been
written since the VM was started, QEMU thinks that 10 MB of data has
been written in this slice. This leads to a I/O lockup in the guest.

We fix this by delaying the start of a new slice to the next
call of bdrv_exceed_io_limits().

Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
raw-posix: support discard on more filesystems

Linux 2.6.38 introduced the filesystem independent interface to
deallocate part of a file. As of Linux 3.7, btrfs, ext4, ocfs2,
tmpfs and xfs support it.

Even though the system calls here are in practice issued on Linux,
the code is structured to allow plugging in alternatives for other Unix
variants.  EOPNOTSUPP is used unconditionally in this patch, but it is
supported in both OpenBSD and Mac OS X since forever (see for example
http://lists.debian.org/debian-glibc/2006/02/msg00337.html).

Signed-off-by: Kusanagi Kouichi <slash@ac.auone-net.jp>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
raw-posix: remember whether discard failed

Avoid sending system calls repeatedly if they shall fail.  This
does not apply to XFS: if the filesystem-specific ioctl fails,
something weird is happening.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
raw: support discard on block devices

Block devices use a ioctl instead of fallocate, so add a separate
implementation.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
block: make discard asynchronous

This is easy with the thread pool, because we can use s->is_xfs and
s->has_discard from the worker function.

QEMU has a widespread assumption that each I/O operation writes less
than 2^32 bytes.  This patch doesn't fix it throughout of course,
but it starts correcting struct RawPosixAIOData so that there is
no regression with respect to the synchronous discard implementation.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>