Currently QEMU sets the x86 number of physical address bits to the
magic number 40.  This is only correct on some small AMD systems;
Intel systems tend to have 36, 39, 46 bits, and large AMD systems
tend to have 48.

Having the value different from your actual hardware is detectable
by the guest and in principal can cause problems;
The current limit of 40 stops TB VMs being created by those lucky
enough to have that much.

This patch lets you set the physical bits by a cpu property but
defaults to the same 40bits which matches TCGs setup.

I've removed the ancient warning about the 42 bit limit in exec.c;
I can't find that limit in there and no one else seems to know where
it is.

We use a magic value of 0 as the property default so that we can
later distinguish between the default and a user set value.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>

Provide a constant for the number of address bits supported under TCG.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Suggested-by: NEduardo Habkost <ehabkost@redhat.com>
Reviewed-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>

target-arm queue:
 * fix two minor Coverity complaints

# gpg: Signature made Tue 19 Jul 2016 18:02:34 BST
# gpg:                using RSA key 0x3C2525ED14360CDE
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>"
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>"
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>"
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* remotes/pmaydell/tags/pull-target-arm-20160719:
  arm_gicv3: Add assert()s to tell Coverity that offsets are aligned
  target-arm: Fix unreachable code in gicv3_class_name()
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

linux-user fixes before 2.7 freeze, fix commit message

# gpg: Signature made Tue 19 Jul 2016 14:18:54 BST
# gpg:                using RSA key 0xB44890DEDE3C9BC0
# gpg: Good signature from "Riku Voipio <riku.voipio@iki.fi>"
# gpg:                 aka "Riku Voipio <riku.voipio@linaro.org>"
# Primary key fingerprint: FF82 03C8 C391 98AE 0581  41EF B448 90DE DE3C 9BC0

* remotes/riku/tags/pull-linux-user-20160719-2:
  linux-user: AArch64 has sync_file_range, not sync_file_range2
  linux-user: Fix type for SIOCATMARK ioctl
  linux-user: define missing sparc syscalls
  linux-user: Fix terminal control ioctls
  linux-user: Add some new blk ioctls
  linux-user: Handle short lengths in host_to_target_sockaddr()
  linux-user: Forget about synchronous signal once it is delivered
  linux-user: Correct type for LOOP_GET_STATUS{,64} ioctls
  linux-user: Correct type for BLKSSZGET
  linux-user: Add loop control ioctls
  linux-user: Check sigsetsize argument to syscalls
  linux-user: add nested netlink types
  linux-user: convert sockaddr_ll from host to target
  linux-user: add fd_trans helper in do_recvfrom()
  linux-user: fix netlink memory corruption
  linux-user: fd_trans_*_data() returns the length
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Coverity complains that the GICR_IPRIORITYR case in gicv3_readl()
can overflow an array, because it doesn't know that the offsets
passed to that function must be word aligned. Add some assert()s
which hopefully tell Coverity that this isn't possible.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1468261372-17508-1-git-send-email-peter.maydell@linaro.org

Coverity complains that the exit() in gicv3_class_name()
can be unreachable, because if TARGET_AARCH64 is defined
then all code paths return before reaching it. Move the
exit() up to the error_report() that it belongs with.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NShannon Zhao <shannon.zhao@linaro.org>
Message-id: 1468260552-8400-1-git-send-email-peter.maydell@linaro.org

disas/bfd.h defines ATTRIBUTE_UNUSED, but unfortunately the
ALSA system headers also define this macro, which means that
you can get a compilation failure if building with ALSA and
any files happen to include the alsa headers before bfd.h
rather than the other way around.

This is unfortunate namespace pollution by the ALSA headers but
we can work around it. Add an #ifndef guard to bfd.h and remove
the unnecessary extra definition in disas/arm.c to fix this.
Reported-by: NBALATON Zoltan <balaton@eik.bme.hu>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Message-id: 1468937076-21503-1-git-send-email-peter.maydell@linaro.org

* two old patches from prospective GSoC students
* i386 -kernel device tree support
* Coverity fix
* memory usage improvement from Peter
* checkpatch fix
* g_path_get_dirname cleanup
* caching of block status for iSCSI

# gpg: Signature made Tue 19 Jul 2016 07:43:41 BST
# gpg:                using RSA key 0xBFFBD25F78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* remotes/bonzini/tags/for-upstream:
  target-i386: Remove redundant HF_SOFTMMU_MASK
  block/iscsi: allow caching of the allocation map
  block/iscsi: fix rounding in iscsi_allocationmap_set
  Move README to markdown
  cpu-exec: Move down some declarations in cpu_exec()
  exec: avoid realloc in phys_map_node_reserve
  checkpatch: consider git extended headers valid patches
  megasas: remove useless check for cmd->frame
  compiler: never omit assertions if using a static analysis tool
  hw/i386: add device tree support
  Changed malloc to g_malloc, free to g_free in bsd-user/qemu.h
  use g_path_get_dirname instead of dirname
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Make IRC a little less noisy

# gpg: Signature made Mon 18 Jul 2016 16:42:57 BST
# gpg:                using RSA key 0xFBD0DB095A9E2A44
# gpg: Good signature from "Alex Bennée (Master Work Key) <alex.bennee@linaro.org>"
# Primary key fingerprint: 6685 AE99 E751 67BC AFC8  DF35 FBD0 DB09 5A9E 2A44

* remotes/stsquad/tags/pull-travis-20160718-1:
  .travis.yml: Disable IRC build status updates from forks
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The AArch64 Linux ABI syscall 84 is sync_file_range, not
sync_file_range2 (in the kernel it uses the asm-generic
headers and does not define __ARCH_WANT_SYNC_FILE_RANGE2).
Update our TARGET_NR_* definitions accordingly.

This fixes the sync_file_range syscall which otherwise
gets its arguments in the wrong order.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

The SIOCATMARK ioctl takes an argument which should be a
pointer to an integer where the kernel will write the result.
We were incorrectly declaring it as TYPE_NULL which would mean
it would always fail (with EFAULT) when it should succeed.
Correct the type.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

NR_lookup_dcookie, NR_fadvise64, NR_fadvise64_64
Signed-off-by: NLaurent Vivier <laurent@vivier.eu>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

TIOCGPTN and related terminal control ioctls were not converted to the guest ioctl format on x86_64 targets. Convert these ioctls to enable terminal functionality on x86_64 guests.
Signed-off-by: NTimothy Pearson <tpearson@raptorengineering.com>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

vnc: bugfixes for -rc0

# gpg: Signature made Tue 19 Jul 2016 08:27:05 BST
# gpg:                using RSA key 0x4CB6D8EED3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>"
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>"
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>"
# Primary key fingerprint: A032 8CFF B93A 17A7 9901  FE7D 4CB6 D8EE D3E8 7138

* remotes/kraxel/tags/pull-vnc-20160719-1:
  vnc-tight: fix regression with libxenstore
  vnc-enc-tight: fix off-by-one bug
  vnc: make sure we finish disconnect
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Update OpenBIOS images

# gpg: Signature made Tue 19 Jul 2016 07:42:30 BST
# gpg:                using RSA key 0x5BC2C56FAE0F321F
# gpg: Good signature from "Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>"
# Primary key fingerprint: CC62 1AB9 8E82 200D 915C  C9C4 5BC2 C56F AE0F 321F

* remotes/mcayland/tags/qemu-openbios-signed:
  Update OpenBIOS images to e79bca6 built from submodule.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Add some new blk ioctls (these are 0x12,119 through
to 0x12,127). Several of these are used by mke2fs; this silences
the warnings:

mke2fs 1.42.12 (29-Aug-2014)
Unsupported ioctl: cmd=0x127b
Unsupported ioctl: cmd=0x127a
warning: Unable to get device geometry for /dev/loop5
Unsupported ioctl: cmd=0x127c
Unsupported ioctl: cmd=0x127c
Unsupported ioctl: cmd=0x1277
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

If userspace specifies a short buffer for a target sockaddr,
the kernel will only copy in as much as it has space for
(or none at all if the length is zero) -- see the kernel
move_addr_to_user() function. Mimic this in QEMU's
host_to_target_sockaddr() routine.

In particular, this fixes a segfault running the LTP
recvfrom01 test, where the guest makes a recvfrom()
call with a bad buffer pointer and other parameters which
cause the kernel to set the addrlen to zero; because we
did not skip the attempt to swap the sa_family field we
segfaulted on the bad address.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

Commit 655ed67c which switched synchronous signals to
benig recorded in ts->sync_signal rather than in a queue
with every other signal had a bug: we failed to clear
the flag indicating that a synchronous signal was pending
when we delivered it. This meant that we would take the signal
again and again every time the guest made a syscall.
(This is a bug introduced in my refactoring of Timothy Baldwin's
original code.)

Fix this by passing in the struct emulated_sigtable* to
handle_pending_signal(), so that we clear the pending flag
in the ts->sync_signal struct when handling a synchronous signal.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

The LOOP_GET_STATUS and LOOP_GET_STATUS64 ioctls were incorrectly
defined as IOC_W rather than IOC_R, which meant we weren't
correctly copying the information back from the kernel to the guest.
The loop_info64 structure definition was also missing a member
and using the wrong type for several 32-bit fields.

In particular, this meant that "kpartx -d image.img" didn't work
and "losetup -a" behaved strangely. Correct the ioctl type definitions.
Reported-by: NChanho Park <chanho61.park@samsung.com>
Reviewed-by: NLaurent Vivier <laurent@vivier.eu>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

The BLKSSZGET ioctl takes an argument which is a pointer to an int.
We were incorrectly declaring it to take a pointer to a long, which
meant that we would incorrectly write to memory which we should not
if the guest is a 64-bit architecture.

In particular, kpartx uses this ioctl to write to an int on the
stack, which tends to result in it crashing immediately.
Reported-by: NChanho Park <chanho61.park@samsung.com>
Reviewed-by: NLaurent Vivier <laurent@vivier.eu>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

Add support for the /dev/loop-control ioctls:
 LOOP_CTL_ADD
 LOOP_CTL_REMOVE
 LOOP_CTL_GET_FREE

[RV: fixed to apply to new header guards]
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NLaurent Vivier <laurent@vivier.eu>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

Many syscalls which take a sigset_t argument also take an argument
giving the size of the sigset_t.  The kernel insists that this
matches its idea of the type size and fails EINVAL if it is not.
Implement this logic in QEMU.  (This mostly just means some LTP test
cases which check error cases now pass.)
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>
Reviewed-by: NLaurent Vivier <laurent@vivier.eu>

Nested types are used by the kernel to send link information and
protocol properties.

We can see following errors with "ip link show":

Unimplemented nested type 26
Unimplemented nested type 26
Unimplemented nested type 18
Unimplemented nested type 26
Unimplemented nested type 18
Unimplemented nested type 26

This patch implements nested types 18 (IFLA_LINKINFO) and
26 (IFLA_AF_SPEC).
Signed-off-by: NLaurent Vivier <laurent@vivier.eu>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

As we convert sockaddr for AF_PACKET family for sendto() (target to
host) we need also to convert this for getsockname() (host to target).

arping uses getsockname() to get the the interface address and uses
this address with sendto().

Tested with:

    /sbin/arping -D -q -c2 -I eno1 192.168.122.88

...
getsockname(3, {sa_family=AF_PACKET, proto=0x806, if2,
pkttype=PACKET_HOST, addr(6)={1, 10c37b6b9a76}, [18]) = 0
...
sendto(3, "..." 28, 0,
       {sa_family=AF_PACKET, proto=0x806, if2, pkttype=PACKET_HOST,
       addr(6)={1, ffffffffffff}, 20) = 28
...
Signed-off-by: NLaurent Vivier <laurent@vivier.eu>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

Fix passwd using netlink audit.
Signed-off-by: NLaurent Vivier <laurent@vivier.eu>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

Netlink is byte-swapping data in the guest memory (it's bad).

It's ok when the data come from the host as they are generated by the
host.

But it doesn't work when data come from the guest: the guest can
try to reuse these data whereas they have been byte-swapped.

This is what happens in glibc:

glibc generates a sequence number in nlh.nlmsg_seq and calls
sendto() with this nlh. In sendto(), we byte-swap nlmsg.seq.

Later, after the recvmsg(), glibc compares nlh.nlmsg_seq with
sequence number given in return, and of course it fails (hangs),
because nlh.nlmsg_seq is not valid anymore.

The involved code in glibc is:

sysdeps/unix/sysv/linux/check_pf.c:make_request()
...
  req.nlh.nlmsg_seq = time (NULL);
...
  if (TEMP_FAILURE_RETRY (__sendto (fd, (void *) &req, sizeof (req), 0,
                                    (struct sockaddr *) &nladdr,
                                    sizeof (nladdr))) < 0)
<here req.nlh.nlmsg_seq has been byte-swapped>
...
  do
    {
...
      ssize_t read_len = TEMP_FAILURE_RETRY (__recvmsg (fd, &msg, 0));
...
      struct nlmsghdr *nlmh;
      for (nlmh = (struct nlmsghdr *) buf;
           NLMSG_OK (nlmh, (size_t) read_len);
           nlmh = (struct nlmsghdr *) NLMSG_NEXT (nlmh, read_len))
        {
<we compare nlmh->nlmsg_seq with corrupted req.nlh.nlmsg_seq>
          if (nladdr.nl_pid != 0 || (pid_t) nlmh->nlmsg_pid != pid
              || nlmh->nlmsg_seq != req.nlh.nlmsg_seq)
            continue;
...
          else if (nlmh->nlmsg_type == NLMSG_DONE)
            /* We found the end, leave the loop.  */
            done = true;
        }
    }
  while (! done);

As we have a continue on "nlmh->nlmsg_seq != req.nlh.nlmsg_seq",
"done" cannot be set to "true" and we have an infinite loop.

It's why commands like "apt-get update" or "dnf update hangs".
Signed-off-by: NLaurent Vivier <laurent@vivier.eu>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

fd_trans_target_to_host_data() and fd_trans_host_to_target_data() must
return the length of processed data.
Signed-off-by: NLaurent Vivier <laurent@vivier.eu>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

# gpg: Signature made Tue 19 Jul 2016 03:33:40 BST
# gpg:                using RSA key 0xEF04965B398D6211
# gpg: Good signature from "Jason Wang (Jason Wang on RedHat) <jasowang@redhat.com>"
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 215D 46F4 8246 689E C77F  3562 EF04 965B 398D 6211

* remotes/jasowang/tags/net-pull-request:
  e1000e: fix building without CONFIG_VMXNET3_PCI
  MAINTAINERS: release Scott from being a rocker maintainer
  tap: fix memory leak on failure to create a multiqueue tap device
  net: fix incorrect argument to iov_to_buf
  net: fix incorrect access to pointer
  e1000e: fix incorrect access to pointer
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

# gpg: Signature made Mon 18 Jul 2016 23:53:15 BST
# gpg:                using RSA key 0x7DEF8106AAFC390E
# gpg: Good signature from "John Snow (John Huston) <jsnow@redhat.com>"
# Primary key fingerprint: FAEB 9711 A12C F475 812F  18F2 88A9 064D 1835 61EB
#      Subkey fingerprint: F9B7 ABDB BCAC DF95 BE76  CBD0 7DEF 8106 AAFC 390E

* remotes/jnsnow/tags/ide-pull-request:
  block: ignore flush requests when storage is clean
  tests: in IDE and AHCI tests perform DMA write before flushing
  ide: set retry_unit for PIO and FLUSH requests
  ide: refactor retry_unit set and clear into separate function
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

# gpg: Signature made Mon 18 Jul 2016 22:59:55 BST
# gpg:                using RSA key 0x9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/tracing-pull-request:
  trace: Add QAPI/QMP interfaces to query and control per-vCPU tracing state
  trace: Allow event name pattern in "info trace-events"
  trace: Conditionally trace events based on their per-vCPU state
  trace: Add per-vCPU tracing states for events with the 'vcpu' property
  trace: Cosmetic changes on fast-path tracing
  disas: Remove unused macro '_'
  trace: Identify events with the 'vcpu' property
  trace: [bsd-user] Commandline arguments to control tracing
  trace: [linux-user] Commandline arguments to control tracing
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

VFIO update 2016-07-18

One fix for 2.7-rc0 which hides the ARI extended capability, fixing
multifunction support in PCIe configurations where the assigned device
function topology does not match the host (Alex Williamson)

# gpg: Signature made Mon 18 Jul 2016 18:02:27 BST
# gpg:                using RSA key 0x239B9B6E3BB08B22
# gpg: Good signature from "Alex Williamson <alex.williamson@redhat.com>"
# gpg:                 aka "Alex Williamson <alex@shazbot.org>"
# gpg:                 aka "Alex Williamson <alwillia@redhat.com>"
# gpg:                 aka "Alex Williamson <alex.l.williamson@gmail.com>"
# Primary key fingerprint: 42F6 C04E 540B D1A9 9E7B  8A90 239B 9B6E 3BB0 8B22

* remotes/awilliam/tags/vfio-update-20160718.0:
  vfio/pci: Hide ARI capability
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Signed-off-by: NMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>

'HF_SOFTMMU_MASK' is only set when 'CONFIG_SOFTMMU' is defined. So
there's no need in this flag: test 'CONFIG_SOFTMMU' instead.
Suggested-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NSergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: NSergey Fedorov <sergey.fedorov@linaro.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Message-Id: <20160715175852.30749-6-sergey.fedorov@linaro.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

until now the allocation map was used only as a hint if a cluster
is allocated or not. If a block was not allocated (or Qemu had
no info about the allocation status) a get_block_status call was
issued to check the allocation status and possibly avoid
a subsequent read of unallocated sectors. If a block known to be
allocated the get_block_status call was omitted. In the other case
a get_block_status call was issued before every read to avoid
the necessity for a consistent allocation map. To avoid the
potential overhead of calling get_block_status for each and
every read request this took only place for the bigger requests.

This patch enhances this mechanism to cache the allocation
status and avoid calling get_block_status for blocks where
the allocation status has been queried before. This allows
for bypassing the read request even for smaller requests and
additionally omits calling get_block_status for known to be
unallocated blocks.
Signed-off-by: NPeter Lieven <pl@kamp.de>
Message-Id: <1468831940-15556-3-git-send-email-pl@kamp.de>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

when setting clusters as alloacted the boundaries have
to be expanded. As Paolo pointed out the calculation of
the number of clusters is wrong:

Suppose cluster_sectors is 2, sector_num = 1, nb_sectors = 6:

In the "mark allocated" case, you want to set 0..8, i.e.
cluster_num=0, nb_clusters=4.

   0--.--2--.--4--.--6--.--8
   <--|_________________|-->  (<--> = expanded)

Instead you are setting nb_clusters=3, so that 6..8 is not marked.

   0--.--2--.--4--.--6--.--8
   <--|______________|!!!     (! = wrong)

Cc: qemu-stable@nongnu.org
Reported-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NPeter Lieven <pl@kamp.de>
Message-Id: <1468831940-15556-2-git-send-email-pl@kamp.de>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Move the README file to markdown so that it makes the github page look
prettier. I know that github repo is a mirror and not the official
repo, but I think it doesn't hurt to have it in markdown format.
Signed-off-by: NPranith Kumar <bobby.prani@gmail.com>
Message-Id: <20160715043111.29007-1-bobby.prani@gmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Some guests (win2008 server for example) do a lot of unnecessary
flushing when underlying media has not changed. This adds additional
overhead on host when calling fsync/fdatasync.

This change introduces a write generation scheme in BlockDriverState.
Current write generation is checked against last flushed generation to
avoid unnessesary flushes.

The problem with excessive flushing was found by a performance test
which does parallel directory tree creation (from 2 processes).
Results improved from 0.424 loops/sec to 0.432 loops/sec.
Each loop creates 10^3 directories with 10 files in each.

This affected some blkdebug testcases that were expecting error logs from
failure-injected flushes which are now skipped entirely
(tests 026 071 089).

This also affects the performance of block jobs and thus BLOCK_JOB_READY
events for driver-mirror and active block-commit commands now arrives
faster, before QMP send successfully returns to caller (tests 141 144).
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: 1468870792-7411-5-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>

Due to changes in flush behaviour clean disks stopped generating
flush_to_disk events and IDE and AHCI tests that test flush commands
started to fail.

This change adds additional DMA writes to affected tests before sending
flush commands so that bdrv_flush actually generates flush_to_disk event.
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: 1468870792-7411-4-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 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>