Commit Graph

45381 Commits

Author SHA1 Message Date
Eric Blake
441692ddd8 onenand: Switch to byte-based block access
Sector-based blk_write() should die; switch to byte-based
blk_pwrite() instead.  Likewise for blk_read().

This particular device picks its size during onenand_initfn(),
and can be at most 0x80000000 bytes; therefore, shifting an
'int sec' request to get back to a byte offset should never
overflow 32 bits.  But adding assertions to document that point
should not hurt.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:09 +02:00
Eric Blake
9fc0d361cc nand: Switch to byte-based block access
Sector-based blk_write() should die; switch to byte-based
blk_pwrite() instead.  Likewise for blk_read().

This file is doing some complex computations to map various
flash page sizes (256, 512, and 2048) atop generic uses of
512-byte sector operations.  Perhaps someone will want to tidy
up the file for fewer gymnastics in managing addresses and
offsets, and less wasteful visits of 256-byte pages, but it
was out of scope for this series, where I just went with the
mechanical conversion.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:09 +02:00
Eric Blake
a7a5b7c0fc fdc: Switch to byte-based block access
Sector-based blk_write() should die; switch to byte-based
blk_pwrite() instead.  Likewise for blk_read().

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:09 +02:00
Eric Blake
d00000f901 xen_disk: Switch to byte-based aio block access
Sector-based blk_aio_readv() and blk_aio_writev() should die; switch
to byte-based blk_aio_preadv() and blk_aio_pwritev() instead.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:09 +02:00
Eric Blake
b5772fdde4 virtio: Switch to byte-based aio block access
Sector-based blk_aio_readv() and blk_aio_writev() should die; switch
to byte-based blk_aio_preadv() and blk_aio_pwritev() instead.

The trace is modified at the same time, and nb_sectors is now
unused.  Fix a comment typo while in the vicinity.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:09 +02:00
Eric Blake
03c90063cc scsi-disk: Switch to byte-based aio block access
Sector-based blk_aio_readv() and blk_aio_writev() should die; switch
to byte-based blk_aio_preadv() and blk_aio_pwritev() instead.

As part of the cleanup, scsi_init_iovec() no longer needs to return
a value, and reword a comment.

[ kwolf: Fix read accounting change ]

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:09 +02:00
Eric Blake
d4f510eb3f ide: Switch to byte-based aio block access
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: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:08 +02:00
Eric Blake
60cb2fa7eb block: Introduce byte-based aio read/write
blk_aio_readv() and blk_aio_writev() are annoying in that they
can't access sub-sector granularity, and cannot pass flags.
Also, they require the caller to pass redundant information
about the size of the I/O (qiov->size in bytes must match
nb_sectors in sectors).

Add new blk_aio_preadv() and blk_aio_pwritev() functions to fix
the flaws. The next few patches will upgrade callers, then
finally delete the old interfaces.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:08 +02:00
Eric Blake
983a160050 block: Switch blk_*write_zeroes() to byte interface
Sector-based blk_write() should die; convert the one-off
variant blk_write_zeroes() to use an offset/count interface
instead.  Likewise for blk_co_write_zeroes() and
blk_aio_write_zeroes().

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:08 +02:00
Eric Blake
b7d17f9fa4 block: Switch blk_read_unthrottled() to byte interface
Sector-based blk_read() should die; convert the one-off
variant blk_read_unthrottled().

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:08 +02:00
Eric Blake
8341f00dc2 block: Allow BDRV_REQ_FUA through blk_pwrite()
We have several block drivers that understand BDRV_REQ_FUA,
and emulate it in the block layer for the rest by a full flush.
But without a way to actually request BDRV_REQ_FUA during a
pass-through blk_pwrite(), FUA-aware block drivers like NBD are
forced to repeat the emulation logic of a full flush regardless
of whether the backend they are writing to could do it more
efficiently.

This patch just wires up a flags argument; followup patches
will actually make use of it in the NBD driver and in qemu-io.

Signed-off-by: Eric Blake <eblake@redhat.com>
Acked-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:08 +02:00
Kevin Wolf
0e01b76e7c qemu-io: Fix memory leak in 'aio_write -z'
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-05-12 15:22:08 +02:00
Janne Karhunen
f249924e96 Allow users to specify the vmdk virtual hardware version.
Vmdk images have metadata to indicate the vmware virtual
hardware version image was created/tested to run with.
Allow users to specify that version via new 'hwversion'
option.

[ kwolf: Adjust qemu-iotests common.filter ]

Signed-off-by: Janne Karhunen <Janne.Karhunen@gmail.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:08 +02:00
Zhou Jie
ed79f37d9b block: always compile-check debug prints
Files with conditional debug statements should ensure that the printf is
always compiled. This prevents bitrot of the format string of the debug
statement. And switch debug output to stderr.

Signed-off-by: Zhou Jie <zhoujie2011@cn.fujitsu.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:08 +02:00
Wei Jiangang
547cb1574e block: Fix typo in comment
s/imlement/implement/

Signed-off-by: Wei Jiangang <weijg.fnst@cn.fujitsu.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:08 +02:00
Kevin Wolf
e3ddef25e9 block: Remove BlockDriver.bdrv_read/write
There are no block drivers left that implement the old .bdrv_read/write
interface, so it can be removed now. This gets us rid of the
corresponding emulation functions, too.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12 15:22:08 +02:00
Kevin Wolf
4575eb496d vvfat: Implement .bdrv_co_preadv/pwritev interfaces
This doesn't really convert any of the actual vvfat logic to use
vectored I/O (and it's doubtful whether that would make sense), but
instead just adapts the wrappers to the modern interface.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12 15:22:08 +02:00
Kevin Wolf
513b0f026b vpc: Implement .bdrv_co_pwritev() interface
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12 15:22:08 +02:00
Kevin Wolf
d46b7cc680 vpc: Implement .bdrv_co_preadv() interface
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12 15:22:08 +02:00
Kevin Wolf
37b1d7d8c9 vmdk: Implement .bdrv_co_pwritev() interface
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12 15:22:08 +02:00
Kevin Wolf
f10cc24359 vmdk: Implement .bdrv_co_preadv() interface
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12 15:22:08 +02:00
Kevin Wolf
a844a2b0d4 vmdk: Add vmdk_find_offset_in_cluster()
This is a byte granularity version of vmdk_find_index_in_cluster().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12 15:22:08 +02:00
Kevin Wolf
fde9d56f5b vdi: Implement .bdrv_co_pwritev() interface
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12 15:22:08 +02:00
Kevin Wolf
0865bb6f04 vdi: Implement .bdrv_co_preadv() interface
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12 15:22:08 +02:00
Kevin Wolf
3edf1e73d5 dmg: Implement .bdrv_co_preadv() interface
This implements .bdrv_co_preadv() for the cloop block driver. While
updating the error paths, change -1 to a valid -errno code.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12 15:22:08 +02:00
Kevin Wolf
5cd230819e cloop: Implement .bdrv_co_preadv() interface
This implements .bdrv_co_preadv() for the cloop block driver. While
updating the error paths, change -1 to a valid -errno code.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12 15:22:08 +02:00
Kevin Wolf
3b8fd33011 bochs: Implement .bdrv_co_preadv() interface
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12 15:22:08 +02:00
Kevin Wolf
3fb06697ae block: Introduce .bdrv_co_preadv/pwritev BlockDriver function
Many parts of the block layer are already byte granularity. The block
driver interface, however, was still missing an interface that allows
making use of this. This patch introduces a new BlockDriver interface,
which is based on coroutines, vectored, has flags and uses a byte
granularity. This is now the preferred interface for new drivers.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12 15:22:08 +02:00
Kevin Wolf
cab3a3563c block: Rename bdrv_co_do_preadv/writev to bdrv_co_preadv/writev
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: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12 15:22:08 +02:00
Kevin Wolf
0884447382 block: Support AIO drivers in bdrv_driver_preadv/pwritev()
Instead of registering emulation functions as .bdrv_co_writev, just
directly check whether the function is there or not, and use the AIO
interface if it isn't. This makes the read/write functions more
consistent with how things are done in other places (flush, discard,
etc.)

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12 15:22:07 +02:00
Kevin Wolf
78a07294d5 block: Introduce bdrv_driver_pwritev()
This is a function that simply calls into the block driver for doing a
write, providing the byte granularity interface we want to eventually
have everywhere, and using whatever interface that driver supports.

This one is a bit more interesting than the version for reads: It adds
support for .bdrv_co_writev_flags() everywhere, so that drivers
implementing this function can drop .bdrv_co_writev() now.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12 15:22:07 +02:00
Kevin Wolf
166fe96051 block: Introduce bdrv_driver_preadv()
This is a function that simply calls into the block driver for doing a
read, providing the byte granularity interface we want to eventually
have everywhere, and using whatever interface that driver supports.

For now, this is just a wrapper for calling bs->drv->bdrv_co_readv().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-12 15:22:07 +02:00
Paolo Bonzini
dd7f7ed104 linux-aio: make it more type safe
Replace void* with an opaque LinuxAioState type.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:07 +02:00
Paolo Bonzini
6b98bd6495 block: plug whole tree at once, introduce bdrv_io_unplugged_begin/end
Extract the handling of io_plug "depth" from linux-aio.c and let the
main bdrv_drain loop do nothing but wait on I/O.

Like the two newly introduced functions, bdrv_io_plug and bdrv_io_unplug
now operate on all children.  The visit order is now symmetrical between
plug and unplug, making it possible for formats to implement plug/unplug.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:07 +02:00
Paolo Bonzini
ce0f141259 block: introduce bdrv_no_throttling_begin/end
Extract the handling of throttling from bdrv_flush_io_queue.  These
new functions will soon become BdrvChildRole callbacks, as they can
be generalized to "beginning of drain" and "end of drain".

Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:07 +02:00
Paolo Bonzini
b6e84c97ed block: extract bdrv_drain_poll/bdrv_co_yield_to_drain from bdrv_drain/bdrv_co_drain
Do not call bdrv_drain_recurse twice in bdrv_co_drain.  A small
tweak to the logic in Fam's patch, which is harmless since no
one implements bdrv_drain anyway.  But better get it right.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:07 +02:00
Paolo Bonzini
a72f641407 block: move restarting of throttled reqs to block/throttle-groups.c
We want to remove throttled_reqs from block/io.c.  This is the easy
part---hide the handling of throttled_reqs during disable/enable of
throttling within throttle-groups.c.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:07 +02:00
Paolo Bonzini
733bbc8cea block: make bdrv_start_throttled_reqs return void
The return value is unused and I am not sure why it would be useful.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:07 +02:00
Kevin Wolf
90c78624f1 block: Don't disable I/O throttling on sync requests
We had to disable I/O throttling with synchronous requests because we
didn't use to run timers in nested event loops when the code was
introduced. This isn't true any more, and throttling works just fine
even when using the synchronous API.

The removed code is in fact dead code since commit a8823a3b ('block: Use
blk_co_pwritev() for blk_write()') because I/O throttling can only be
set on the top layer, but BlockBackend always uses the coroutine
interface now instead of using the sync API emulation in block.c.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <1458660792-3035-2-git-send-email-kwolf@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:07 +02:00
Peter Maydell
26617924e9 Open 2.7 development tree
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-12 12:35:25 +01:00
Peter Maydell
bfc766d38e Update version for v2.6.0 release
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-11 16:44:26 +01:00
Peter Maydell
860a3b3485 Update version for v2.6.0-rc5 release
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-09 14:08:12 +01:00
Peter Maydell
53db932604 vga security fixes (CVE-2016-3710, CVE-2016-3712)
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Merge remote-tracking branch 'remotes/kraxel/tags/pull-vga-20160509-1' into staging

vga security fixes (CVE-2016-3710, CVE-2016-3712)

# gpg: Signature made Mon 09 May 2016 13:39:30 BST using RSA key ID D3E87138
# 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>"

* remotes/kraxel/tags/pull-vga-20160509-1:
  vga: make sure vga register setup for vbe stays intact (CVE-2016-3712).
  vga: update vga register setup on vbe changes
  vga: factor out vga register setup
  vga: add vbe_enabled() helper
  vga: fix banked access bounds checking (CVE-2016-3710)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-09 13:42:25 +01:00
Peter Maydell
975eb6a547 Update version for v2.6.0-rc4 release
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-02 17:27:01 +01:00
Gerd Hoffmann
1beb99f787 Revert "acpi: mark PMTIMER as unlocked"
This reverts commit 7070e085d4.

Commit message claims locking is not needed, but that appears
to not be true, seabios ehci driver runs into timekeeping problems
with this, see
	https://bugzilla.redhat.com/show_bug.cgi?id=1322713

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 1460702609-25971-1-git-send-email-kraxel@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-02 17:19:13 +01:00
Gerd Hoffmann
fd3c136b3e vga: make sure vga register setup for vbe stays intact (CVE-2016-3712).
Call vbe_update_vgaregs() when the guest touches GFX, SEQ or CRT
registers, to make sure the vga registers will always have the
values needed by vbe mode.  This makes sure the sanity checks
applied by vbe_fixup_regs() are effective.

Without this guests can muck with shift_control, can turn on planar
vga modes or text mode emulation while VBE is active, making qemu
take code paths meant for CGA compatibility, but with the very
large display widths and heigts settable using VBE registers.

Which is good for one or another buffer overflow.  Not that
critical as they typically read overflows happening somewhere
in the display code.  So guests can DoS by crashing qemu with a
segfault, but it is probably not possible to break out of the VM.

Fixes: CVE-2016-3712
Reported-by: Zuozhi Fzz <zuozhi.fzz@alibaba-inc.com>
Reported-by: P J P <ppandit@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-02 16:02:59 +02:00
Gerd Hoffmann
2068192dcc vga: update vga register setup on vbe changes
Call the new vbe_update_vgaregs() function on vbe configuration
changes, to make sure vga registers are up-to-date.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-02 16:02:59 +02:00
Gerd Hoffmann
7fa5c2c5dc vga: factor out vga register setup
When enabling vbe mode qemu will setup a bunch of vga registers to make
sure the vga emulation operates in correct mode for a linear
framebuffer.  Move that code to a separate function so we can call it
from other places too.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-02 16:02:59 +02:00
Gerd Hoffmann
bfa0f151a5 vga: add vbe_enabled() helper
Makes code a bit easier to read.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-02 16:02:59 +02:00
Gerd Hoffmann
3bf1817079 vga: fix banked access bounds checking (CVE-2016-3710)
vga allows banked access to video memory using the window at 0xa00000
and it supports a different access modes with different address
calculations.

The VBE bochs extentions support banked access too, using the
VBE_DISPI_INDEX_BANK register.  The code tries to take the different
address calculations into account and applies different limits to
VBE_DISPI_INDEX_BANK depending on the current access mode.

Which is probably effective in stopping misprogramming by accident.
But from a security point of view completely useless as an attacker
can easily change access modes after setting the bank register.

Drop the bogus check, add range checks to vga_mem_{readb,writeb}
instead.

Fixes: CVE-2016-3710
Reported-by: Qinghao Tang <luodalongde@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-02 16:02:59 +02:00