ATA8-APT defines the state transitions for both a host controller and
for the hardware device during the lifecycle of a DMA transfer, in
section 9.7 "DMA command protocol."

One of the interesting tidbits here is that when a device transitions
from DDMA0 ("Prepare state") to DDMA1 ("Data_Transfer State"), it can
choose to set either BSY or DRQ to signal this transition, but not both.

as ide_sector_dma_start is the last point in our preparation process
before we begin the real data transfer process (for either AHCI or BMDMA),
this is the correct transition point for DDMA0 to DDMA1.

I have chosen !BSY && DRQ for QEMU to make the transition from DDMA0 the
most obvious.
Reported-by: NBenjamin David Lunt <fys@fysnet.net>
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Tested-by: NStefan Weil <sw@weilnetz.de>
Message-id: 1470175541-19344-1-git-send-email-jsnow@redhat.com
Signed-off-by: NJohn Snow <jsnow@redhat.com>

The isa_register_portio_list() function allocates ioports
data/state. Let's keep the reference to this data on some owner.  This
isn't enough to fix leaks, but at least, ASAN stops complaining of
direct leaks. Further cleanup would require calling
portio_list_del/destroy().
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>

This allows the creation of an empty ide-cd device without manually
creating a BlockBackend.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Acked-by: NEric Blake <eblake@redhat.com>

Followup to 87ac25fd, this time for ATAPI DMA.
Reported-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Message-id: 1470164128-28158-1-git-send-email-jsnow@redhat.com
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NJohn Snow <jsnow@redhat.com>

res_count should be set to the number of outstanding bytes after a DBDMA
request. Unfortunately this wasn't being set to zero by the non-block
transfer codepath meaning drivers that checked the descriptor result for
such requests (e.g reading the CDROM TOC) would assume from a non-zero result
that the transfer had failed.
Signed-off-by: NMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

ahci-test /x86_64/ahci/io/dma/lba28/retry triggers the following leak:

Direct leak of 16 byte(s) in 1 object(s) allocated from:
    #0 0x7fc4b2a25e20 in malloc (/lib64/libasan.so.3+0xc6e20)
    #1 0x7fc4993bce58 in g_malloc (/lib64/libglib-2.0.so.0+0x4ee58)
    #2 0x556a187d4b34 in ahci_populate_sglist hw/ide/ahci.c:896
    #3 0x556a187d8237 in ahci_dma_prepare_buf hw/ide/ahci.c:1367
    #4 0x556a187b5a1a in ide_dma_cb hw/ide/core.c:844
    #5 0x556a187d7eec in ahci_start_dma hw/ide/ahci.c:1333
    #6 0x556a187b650b in ide_start_dma hw/ide/core.c:921
    #7 0x556a187b61e6 in ide_sector_start_dma hw/ide/core.c:911
    #8 0x556a187b9e26 in cmd_write_dma hw/ide/core.c:1486
    #9 0x556a187bd519 in ide_exec_cmd hw/ide/core.c:2027
    #10 0x556a187d71c5 in handle_reg_h2d_fis hw/ide/ahci.c:1204
    #11 0x556a187d7681 in handle_cmd hw/ide/ahci.c:1254
    #12 0x556a187d168a in check_cmd hw/ide/ahci.c:510
    #13 0x556a187d0afc in ahci_port_write hw/ide/ahci.c:314
    #14 0x556a187d105d in ahci_mem_write hw/ide/ahci.c:435
    #15 0x556a1831d959 in memory_region_write_accessor /home/elmarco/src/qemu/memory.c:525
    #16 0x556a1831dc35 in access_with_adjusted_size /home/elmarco/src/qemu/memory.c:591
    #17 0x556a18323ce3 in memory_region_dispatch_write /home/elmarco/src/qemu/memory.c:1262
    #18 0x556a1828cf67 in address_space_write_continue /home/elmarco/src/qemu/exec.c:2578
    #19 0x556a1828d20b in address_space_write /home/elmarco/src/qemu/exec.c:2635
    #20 0x556a1828d92b in address_space_rw /home/elmarco/src/qemu/exec.c:2737
    #21 0x556a1828daf7 in cpu_physical_memory_rw /home/elmarco/src/qemu/exec.c:2746
    #22 0x556a183068d3 in cpu_physical_memory_write /home/elmarco/src/qemu/include/exec/cpu-common.h:72
    #23 0x556a18308194 in qtest_process_command /home/elmarco/src/qemu/qtest.c:382
    #24 0x556a18309999 in qtest_process_inbuf /home/elmarco/src/qemu/qtest.c:573
    #25 0x556a18309a4a in qtest_read /home/elmarco/src/qemu/qtest.c:585
    #26 0x556a18598b85 in qemu_chr_be_write_impl /home/elmarco/src/qemu/qemu-char.c:387
    #27 0x556a18598c52 in qemu_chr_be_write /home/elmarco/src/qemu/qemu-char.c:399
    #28 0x556a185a2afa in tcp_chr_read /home/elmarco/src/qemu/qemu-char.c:2902
    #29 0x556a18cbaf52 in qio_channel_fd_source_dispatch io/channel-watch.c:84

Follow John Snow recommendation:
  Everywhere else ncq_err is used, it is accompanied by a list cleanup
  except for ncq_cb, which is the case you are fixing here.

  Move the sglist destruction inside of ncq_err and then delete it from
  the other two locations to keep it tidy.

  Call dma_buf_commit in ide_dma_cb after the early return. Though, this
  is also a little wonky because this routine does more than clear the
  list, but it is at the moment the centralized "we're done with the
  sglist" function and none of the other side effects that occur in
  dma_buf_commit will interfere with the reset that occurs from
  ide_restart_bh, I think
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

Each irq is referenced by the IDEBus in ide_init2(), thus we can free
the no longer used array.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Acked-by: NJohn Snow <jsnow@redhat.com>

If one attempts to perform a system_reset after a failed IO request
that causes the VM to enter a paused state, QEMU will segfault trying
to free up the pending IO requests.

These requests have already been completed and freed, though, so all
we need to do is NULL them before we enter the paused state.

Existing AHCI tests verify that halted requests are still resumed
successfully after a STOP event.
Analyzed-by: NLaszlo Ersek <lersek@redhat.com>
Reviewed-by: NLaszlo Ersek <lersek@redhat.com>
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Message-id: 1469635201-11918-2-git-send-email-jsnow@redhat.com
Signed-off-by: NJohn Snow <jsnow@redhat.com>

Change sector-based blk_discard(), blk_co_discard(), and
blk_aio_discard() to instead be byte-based blk_pdiscard(),
blk_co_pdiscard(), and blk_aio_pdiscard().  NBD gets a lot
simpler now that ignoring the unaligned portion of a
byte-based discard request is handled under the hood by
the block layer.
Signed-off-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Message-id: 1468624988-423-6-git-send-email-eblake@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

The following sequence of tests discovered a problem in IDE emulation:
1. Send DMA write to IDE device 0
2. Send CMD_FLUSH_CACHE to same IDE device which will be failed by block
layer using blkdebug script in tests/ide-test:test_retry_flush

When doing DMA request ide/core.c will set s->retry_unit to s->unit in
ide_start_dma. When dma completes ide_set_inactive sets retry_unit to -1.
After that ide_flush_cache runs and fails thanks to blkdebug.
ide_flush_cb calls ide_handle_rw_error which asserts that s->retry_unit
== s->unit. But s->retry_unit is still -1 after previous DMA completion
and flush does not use anything related to retry.

This patch restricts retry unit assertion only to ops that actually use
retry logic.
Signed-off-by: NEvgeny Yakovlev <eyakovlev@virtuozzo.com>
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 1468870792-7411-3-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
CC: Max Reitz <mreitz@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Fam Zheng <famz@redhat.com>
CC: John Snow <jsnow@redhat.com>
Signed-off-by: NJohn Snow <jsnow@redhat.com>

Code to set and clear state associated with retry in moved into
ide_set_retry and ide_clear_retry to make adding retry setups easier.
Signed-off-by: NEvgeny Yakovlev <eyakovlev@virtuozzo.com>
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 1468870792-7411-2-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
CC: Max Reitz <mreitz@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Fam Zheng <famz@redhat.com>
CC: John Snow <jsnow@redhat.com>
Signed-off-by: NJohn Snow <jsnow@redhat.com>

The rerror/werror policies are implemented in the devices, so that's
where they should be configured. In comparison to the old options in
-drive, the qdev properties are only added to those devices that
actually support them.

If the option isn't given (or "auto" is specified), the setting of the
BlockBackend is used for compatibility with the old options. For block
jobs, "auto" is the same as "enospc".
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

As cache.writeback is a BlockBackend property and as such more related
to the guest device than the BlockDriverState, we already removed it
from the blockdev-add interface. This patch adds the new way to set it,
as a qdev property of the corresponding guest device.

For example: -drive if=none,file=test.img,node-name=img
             -device ide-hd,drive=img,write-cache=off
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

Tracked down with an ugly, brittle and probably buggy Perl script.

Also move includes converted to <...> up so they get included before
ours where that's obviously okay.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Tested-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

msi_init() reports errors with error_report(), which is wrong
when it's used in realize().

Fix by converting it to Error.

Fix its callers to handle failure instead of ignoring it.

For those callers who don't handle the failure, it might happen:
when user want msi on, but he doesn't get what he want because of
msi_init fails silently.

cc: Gerd Hoffmann <kraxel@redhat.com>
cc: John Snow <jsnow@redhat.com>
cc: Dmitry Fleytman <dmitry@daynix.com>
cc: Jason Wang <jasowang@redhat.com>
cc: Michael S. Tsirkin <mst@redhat.com>
cc: Hannes Reinecke <hare@suse.de>
cc: Paolo Bonzini <pbonzini@redhat.com>
cc: Alex Williamson <alex.williamson@redhat.com>
cc: Markus Armbruster <armbru@redhat.com>
cc: Marcel Apfelbaum <marcel@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NCao jin <caoj.fnst@cn.fujitsu.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>

The patch moves "hw/ide/achi.h", "hw/ide/pci.h" and "hw/ide/internal.h" headers
to corresponding folders inside "include" folder alike other Qemu headers.
Signed-off-by: NEfimov Vasily <real@ispras.ru>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

We only care about the associated backend, so blk_drain is more
appropriate here.
Signed-off-by: NFam Zheng <famz@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Message-id: 20160612065603.21911-1-famz@redhat.com
Signed-off-by: NJohn Snow <jsnow@redhat.com>

error_propagate() already ignores local_err==NULL, so there's no
need to check it before calling.

Coccinelle patch used to perform the changes added to
scripts/coccinelle/error_propagate_null.cocci.
Reviewed-by: NEric Blake <eblake@redhat.com>
Acked-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Message-Id: <1465855078-19435-2-git-send-email-ehabkost@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

This ensures that the underlying memory is marked dirty once the transfer
is complete and resolves cache coherency problems under MacOS 9.
Signed-off-by: NMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

Signed-off-by: NMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

Callers of dma_blk_io have no way to pass extra data to the DMAIOFunc,
because the original callback and opaque are gone by the time DMAIOFunc
is called.  On the other hand, the BlockBackend is usually derived
from those extra data that you could pass to the DMAIOFunc (in the
next patch, that would be the SCSIRequest).

So change DMAIOFunc's prototype, decoupling it from blk_aio_readv
and blk_aio_writev's.  The new prototype loses the BlockBackend
and gains an extra opaque value which, in the case of dma_blk_readv
and dma_blk_writev, is of course used for the BlockBackend.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Sector-based blk_read() should die; switch to byte-based
blk_pread() instead.

Add new defines ATAPI_SECTOR_BITS and ATAPI_SECTOR_SIZE to
use anywhere we were previously scaling BDRV_SECTOR_* by 4,
for better legibility.
Signed-off-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Sector-based blk_aio_readv() and blk_aio_writev() should die; switch
to byte-based blk_aio_preadv() and blk_aio_pwritev() instead.

The patch had to touch multiple files at once, because dma_blk_io()
takes pointers to the functions, and ide_issue_trim() piggybacks on
the same interface (while ignoring offset under the hood).
Signed-off-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

It used to be an internal helper function just for implementing
bdrv_co_do_readv/writev(), but now that it's a public interface, it
deserves a name without "do" in it.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>

Restart of ATAPI DMA used to be unreachable, because the request to do
so wasn't indicated in bus->error_status due to the lack of spare bits, and
ide_restart_bh() would return early doing nothing.

This patch makes use of the observation that not all bit combinations were
possible in ->error_status. In particular, IDE_RETRY_READ only made sense
together with IDE_RETRY_DMA or IDE_RETRY_PIO. This allows to re-use
IDE_RETRY_READ alone as an indicator of ATAPI DMA restart request.

To makes things more uniform, ATAPI DMA gets its own value for ->dma_cmd.
As a means against confusion, macros are added to test the state of
->error_status.

The patch fixes the restart of both in-flight and pending ATAPI DMA,
following the scheme similar to that of IDE DMA.

[Including a fixup patch:
Message-id: 1460465594-15777-1-git-send-email-pbutsykin@virtuozzo.com
--js]
Signed-off-by: NPavel Butsykin <pbutsykin@virtuozzo.com>
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Message-id: 1459924806-306-4-git-send-email-den@openvz.org
Signed-off-by: NJohn Snow <jsnow@redhat.com>

ide_atapi_dma_restart() used to just complete the DMA with an error,
under the assumption that there isn't enough information to restart it.

However, as the contents of the ->io_buffer is preserved, it looks safe to
just re-evaluate it and dispatch the ATAPI command again.
Signed-off-by: NPavel Butsykin <pbutsykin@virtuozzo.com>
Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com>
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Message-id: 1459924806-306-3-git-send-email-den@openvz.org
Signed-off-by: NJohn Snow <jsnow@redhat.com>

If the migration occurs after the IDE DMA has been set up but before it
has been initiated, the state gets lost upon save/restore. Specifically,
->dma_cb callback gets cleared, so, when the guest eventually starts bus
mastering, the DMA never completes, causing the guest to time out the
operation.

OTOH all the infrastructure is already in place to restart the DMA if
the migration happens while the DMA is in progress.

So reuse that infrastructure, by setting bus->error_status based on
->dma_cmd in pre_save if ->dma_cb callback is already set but DMAING is
clear. This will indicate the need for restart and make sure ->dma_cb
is restored in ide_restart_bh(); howeover since DMAING is clear the state
upon restore will be exactly "ready for DMA" as before the save.
Signed-off-by: NPavel Butsykin <pbutsykin@virtuozzo.com>
Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com>
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Message-id: 1459924806-306-2-git-send-email-den@openvz.org
Signed-off-by: NJohn Snow <jsnow@redhat.com>

After commit e5e78550 (blockdev: Separate BB name management), starting a
guest with PVHVM support result in this assert:
qemu-system-i386: block/block-backend.c:173: blk_delete: Assertion `!blk->name' failed.

A backtrace show that a caller is pci_piix3_xen_ide_unplug().

This patch fix it.
Signed-off-by: NAnthony PERARD <anthony.perard@citrix.com>
Message-id: 1460382666-29885-1-git-send-email-anthony.perard@citrix.com
Signed-off-by: NJohn Snow <jsnow@redhat.com>

piix3_ide_xen_class_init is identical to piix3_ide_class_init
except it's buggy as it does not set exit and does not disable
hotplug properly.

Switch to the generic one.
Reviewed-by: NStefano Stabellini <sstabellini@kernel.org>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Move declarations out of qemu-common.h for functions declared in
utils/ files: e.g. include/qemu/path.h for utils/path.c.
Move inline functions out of qemu-common.h and into new files (e.g.
include/qemu/bcd.h)
Signed-off-by: NVeronia Bahaa <veroniabahaa@gmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This patch replaces get_ticks_per_sec() calls with the macro
NANOSECONDS_PER_SECOND. Also, as there are no callers, get_ticks_per_sec()
is then removed.  This replacement improves the readability and
understandability of code.

For example,

    timer_mod(fdctrl->result_timer,
	      qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + (get_ticks_per_sec() / 50));

NANOSECONDS_PER_SECOND makes it obvious that qemu_clock_get_ns
matches the unit of the expression on the right side of the plus.
Signed-off-by: NRutuja Shah <rutu.shah.26@gmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Commit 57cb38b3 included qapi/error.h into qemu/osdep.h to get the
Error typedef.  Since then, we've moved to include qemu/osdep.h
everywhere.  Its file comment explains: "To avoid getting into
possible circular include dependencies, this file should not include
any other QEMU headers, with the exceptions of config-host.h,
compiler.h, os-posix.h and os-win32.h, all of which are doing a
similar job to this file and are under similar constraints."
qapi/error.h doesn't do a similar job, and it doesn't adhere to
similar constraints: it includes qapi-types.h.  That's in excess of
100KiB of crap most .c files don't actually need.

Add the typedef to qemu/typedefs.h, and include that instead of
qapi/error.h.  Include qapi/error.h in .c files that need it and don't
get it now.  Include qapi-types.h in qom/object.h for uint16List.

Update scripts/clean-includes accordingly.  Update it further to match
reality: replace config.h by config-target.h, add sysemu/os-posix.h,
sysemu/os-win32.h.  Update the list of includes in the qemu/osdep.h
comment quoted above similarly.

This reduces the number of objects depending on qapi/error.h from "all
of them" to less than a third.  Unfortunately, the number depending on
qapi-types.h shrinks only a little.  More work is needed for that one.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
[Fix compilation without the spice devel packages. - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

If the FIS or DMA engines are already started, do not allow them to be
"restarted." As a side-effect of this change, the migration post-load
routine must be modified to cope. If the engines are listed as "on"
in the migrated registers, they must be cleared to allow the startup
routine to see the transition from "off" to "on".

As a second side-effect, the extra argument to ahci_cond_engine_start
is removed in favor of consistent behavior.
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Message-id: 1454103689-13042-5-git-send-email-jsnow@redhat.com

Currently, we let ahci_cond_start_engines reject weird configurations
where either the DMA (CLB) or FIS engines are said to be started, but
their matching on/off control bit is toggled off.

There should be no way to achieve this, since any time you toggle the
control bit off, the status bit should always follow synchronously.

Preparing for a refactor in cond_start_engines, move the rejection logic
straight up into post_load.
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Message-id: 1454103689-13042-4-git-send-email-jsnow@redhat.com

Instead of relying on ahci_cond_start_engines to maintain the
engine status indicators itself, have the lower-layer CLB and FIS mapper
helpers do it themselves.

This makes the cond_start routine slightly nicer to read, and makes sure
that the status indicators will always be correct.
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Message-id: 1454103689-13042-3-git-send-email-jsnow@redhat.com

Definitely don't try to unmap a garbage address.
Reported-by: NZuozhi fzz <zuozhi.fzz@alibaba-inc.com>
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Message-id: 1454103689-13042-2-git-send-email-jsnow@redhat.com

Signed-off-by: NJohn Snow <jsnow@redhat.com>
Reported-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Message-id: 1453225191-11871-7-git-send-email-jsnow@redhat.com

Split apart the ide_transfer_stop function into two versions: one that
interrupts and one that doesn't. The one that doesn't can be used to
halt any PIO transfers that are in the DRQ phase. It will not halt
any PIO transfers that are currently in the process of buffering data
for the guest to read.
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Reported-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
[Renamed 'etf' to 'end_transfer_func' --js]
Message-id: 1453225191-11871-6-git-send-email-jsnow@redhat.com

Target the drain for just one device.
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Reported-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Message-id: 1453225191-11871-5-git-send-email-jsnow@redhat.com