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  1. 29 11月, 2016 2 次提交
  3. 24 11月, 2016 1 次提交
  5. 23 11月, 2016 9 次提交
  7. 22 11月, 2016 8 次提交
    • E
      block: Pass unaligned discard requests to drivers · 3482b9bc
      由 Eric Blake 提交于 
      Discard is advisory, so rounding the requests to alignment
boundaries is never semantically wrong from the data that
the guest sees.  But at least the Dell Equallogic iSCSI SANs
has an interesting property that its advertised discard
alignment is 15M, yet documents that discarding a sequence
of 1M slices will eventually result in the 15M page being
marked as discarded, and it is possible to observe which
pages have been discarded.

Between commits 9f1963b3 and b8d0a980, we converted the block
layer to a byte-based interface that ultimately ignores any
unaligned head or tail based on the driver's advertised
discard granularity, which means that qemu 2.7 refuses to
pass any discard request smaller than 15M down to the Dell
Equallogic hardware.  This is a slight regression in behavior
compared to earlier qemu, where a guest executing discards
in power-of-2 chunks used to be able to get every page
discarded, but is now left with various pages still allocated
because the guest requests did not align with the hardware's
15M pages.

Since the SCSI specification says nothing about a minimum
discard granularity, and only documents the preferred
alignment, it is best if the block layer gives the driver
every bit of information about discard requests, rather than
rounding it to alignment boundaries early.

Rework the block layer discard algorithm to mirror the write
zero algorithm: always peel off any unaligned head or tail
and manage that in isolation, then do the bulk of the request
on an aligned boundary.  The fallback when the driver returns
-ENOTSUP for an unaligned request is to silently ignore that
portion of the discard request; but for devices that can pass
the partial request all the way down to hardware, this can
result in the hardware coalescing requests and discarding
aligned pages after all.

Reported by: Peter Lieven <pl@kamp.de>
CC: qemu-stable@nongnu.org
Signed-off-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      3482b9bc
    • E
      block: Return -ENOTSUP rather than assert on unaligned discards · 49228d1e
      由 Eric Blake 提交于 
      Right now, the block layer rounds discard requests, so that
individual drivers are able to assert that discard requests
will never be unaligned.  But there are some ISCSI devices
that track and coalesce multiple unaligned requests, turning it
into an actual discard if the requests eventually cover an
entire page, which implies that it is better to always pass
discard requests as low down the stack as possible.

In isolation, this patch has no semantic effect, since the
block layer currently never passes an unaligned request through.
But the block layer already has code that silently ignores
drivers that return -ENOTSUP for a discard request that cannot
be honored (as well as drivers that return 0 even when nothing
was done).  But the next patch will update the block layer to
fragment discard requests, so that clients are guaranteed that
they are either dealing with an unaligned head or tail, or an
aligned core, making it similar to the block layer semantics of
write zero fragmentation.

CC: qemu-stable@nongnu.org
Signed-off-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      49228d1e
    • E
      block: Let write zeroes fallback work even with small max_transfer · b2f95fee
      由 Eric Blake 提交于 
      Commit 443668ca rewrote the write_zeroes logic to guarantee that
an unaligned request never crosses a cluster boundary.  But
in the rewrite, the new code assumed that at most one iteration
would be needed to get to an alignment boundary.

However, it is easy to trigger an assertion failure: the Linux
kernel limits loopback devices to advertise a max_transfer of
only 64k.  Any operation that requires falling back to writes
rather than more efficient zeroing must obey max_transfer during
that fallback, which means an unaligned head may require multiple
iterations of the write fallbacks before reaching the aligned
boundaries, when layering a format with clusters larger than 64k
atop the protocol of file access to a loopback device.

Test case:

$ qemu-img create -f qcow2 -o cluster_size=1M file 10M
$ losetup /dev/loop2 /path/to/file
$ qemu-io -f qcow2 /dev/loop2
qemu-io> w 7m 1k
qemu-io> w -z 8003584 2093056

In fairness to Denis (as the original listed author of the culprit
commit), the faulty logic for at most one iteration is probably all
my fault in reworking his idea.  But the solution is to restore what
was in place prior to that commit: when dealing with an unaligned
head or tail, iterate as many times as necessary while fragmenting
the operation at max_transfer boundaries.
Reported-by: NEd Swierk <eswierk@skyportsystems.com>
CC: qemu-stable@nongnu.org
CC: Denis V. Lunev <den@openvz.org>
Signed-off-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      b2f95fee
    • E
      qcow2: Inform block layer about discard boundaries · ecdbead6
      由 Eric Blake 提交于 
      At the qcow2 layer, discard is only possible on a per-cluster
basis; at the moment, qcow2 silently rounds any unaligned
requests to this granularity.  However, an upcoming patch will
fix a regression in the block layer ignoring too much of an
unaligned discard request, by changing the block layer to
break up a discard request at alignment boundaries; for that
to work, the block layer must know about our limits.

However, we can't go one step further by changing
qcow2_discard_clusters() to assert that requests are always
aligned, since that helper function is reached on paths
outside of the block layer.

CC: qemu-stable@nongnu.org
Signed-off-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      ecdbead6
    • E
      Fix FreeBSD (10.x) build after 7dc9ae43 · a7764f15
      由 Ed Maste 提交于 
      Include sys/user.h for declaration of 'struct kinfo_proc'.
Add -lutil to qemu-ga link for kinfo_getproc.
Signed-off-by: NEd Maste <emaste@freebsd.org>
Message-id: 1479778365-11315-1-git-send-email-emaste@freebsd.org
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
      a7764f15
    • S
      Merge remote-tracking branch 'jtc/tags/block-pull-request' into staging · 06bf33cf
      由 Stefan Hajnoczi 提交于 
      # gpg: Signature made Mon 21 Nov 2016 10:12:43 PM GMT
# gpg:                using RSA key 0xBDBE7B27C0DE3057
# gpg: Good signature from "Jeffrey Cody <jcody@redhat.com>"
# gpg:                 aka "Jeffrey Cody <jeff@codyprime.org>"
# gpg:                 aka "Jeffrey Cody <codyprime@gmail.com>"
# Primary key fingerprint: 9957 4B4D 3474 90E7 9D98  D624 BDBE 7B27 C0DE 3057

* jtc/tags/block-pull-request:
  gluster: Fix use after free in glfs_clear_preopened()

Message-id: 1479766499-29972-1-git-send-email-jcody@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
      06bf33cf
    • G
      seabios: update to 1.10.1 stable release · cae41fda
      由 Gerd Hoffmann 提交于 
      git shortlog rel-1.10.0..rel-1.10.1
===================================

Igor Mammedov (1):
      drop "etc/boot-cpus" fw_cfg file and reuse legacy QEMU_CFG_NB_CPUS
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
      cae41fda
    • K
      gluster: Fix use after free in glfs_clear_preopened() · 668c0e44
      由 Kevin Wolf 提交于 
      This fixes a use-after-free bug introduced in commit 6349c154. We need
to use QLIST_FOREACH_SAFE() when freeing elements in the loop. Spotted
by Coverity.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Message-id: 1479378608-11962-1-git-send-email-kwolf@redhat.com
Signed-off-by: NJeff Cody <jcody@redhat.com>
      668c0e44
  9. 21 11月, 2016 2 次提交
    • S
      Merge remote-tracking branch 'sstabellini/tags/xen-20161108-tag' into staging · ab9125c0
      由 Stefan Hajnoczi 提交于 
      Xen 2016/11/08

# gpg: Signature made Tue 08 Nov 2016 07:48:12 PM GMT
# gpg:                using RSA key 0x894F8F4870E1AE90
# gpg: Good signature from "Stefano Stabellini <sstabellini@kernel.org>"
# gpg:                 aka "Stefano Stabellini <stefano.stabellini@eu.citrix.com>"
# Primary key fingerprint: D04E 33AB A51F 67BA 07D3  0AEA 894F 8F48 70E1 AE90

* sstabellini/tags/xen-20161108-tag:
  xen: Fix xenpv machine initialisation

Message-id: alpine.DEB.2.10.1611081150170.3491@sstabellini-ThinkPad-X260
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
      ab9125c0
    • S
      Merge remote-tracking branch 'mst/tags/for_upstream' into staging · c36ed06e
      由 Stefan Hajnoczi 提交于 
      virtio, vhost, pc: fixes

Most notably this fixes a regression with vhost introduced by the pull before
last.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Fri 18 Nov 2016 03:51:55 PM GMT
# gpg:                using RSA key 0x281F0DB8D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>"
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17  0970 C350 3912 AFBE 8E67
#      Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA  8A0D 281F 0DB8 D28D 5469

* mst/tags/for_upstream:
  acpi: Use apic_id_limit when calculating legacy ACPI table size
  ipmi: fix qemu crash while migrating with ipmi
  ivshmem: Fix 64 bit memory bar configuration
  virtio: set ISR on dataplane notifications
  virtio: access ISR atomically
  virtio: introduce grab/release_ioeventfd to fix vhost
  virtio-crypto: fix virtio_queue_set_notification() race

Message-id: 1479484366-7977-1-git-send-email-mst@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
      c36ed06e
  11. 18 11月, 2016 12 次提交
  13. 17 11月, 2016 4 次提交
  15. 16 11月, 2016 2 次提交