Commit Graph

112 Commits

Author SHA1 Message Date
Kevin Wolf
d9ca2ea2e2 block: Convert bdrv_pwrite(v/_sync) to BdrvChild
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-05 16:46:27 +02:00
Kevin Wolf
cf2ab8fc34 block: Convert bdrv_pread(v) to BdrvChild
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-05 16:46:27 +02:00
Kevin Wolf
0d1049c7d1 block: Convert bdrv_aio_writev() to BdrvChild
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-05 16:46:26 +02:00
Kevin Wolf
ebb7af2173 block: Convert bdrv_aio_readv() to BdrvChild
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-05 16:46:26 +02:00
Eric Blake
49a2e48348 qed: Convert to bdrv_co_pwrite_zeroes()
Another step on our continuing quest to switch to byte-based
interfaces.

Kill an abuse of the comma operator while at it (fortunately,
the semantics were still right).  Also, the test for requests
not aligned to clusters should be applied always, not just
when a backing file is present.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-06-08 10:21:08 +02:00
Eric Blake
cf081fca4e block: Track write zero limits in bytes
Another step towards removing sector-based interfaces: convert
the maximum write and minimum alignment values from sectors to
bytes.  Rename the variables to let the compiler check that all
users are converted to the new semantics.

The maximum remains an int as long as BDRV_REQUEST_MAX_SECTORS
is constrained by INT_MAX (this means that we can't even
support a 2G write_zeroes, but just under it) - changing
operation lengths to unsigned or to 64-bits is a much bigger
audit, and debatable if we even want to do it (since at the
core, a 32-bit platform will still have ssize_t as its
underlying limit on write()).

Meanwhile, alignment is changed to 'uint32_t', since it makes no
sense to have an alignment larger than the maximum write, and
less painful to use an unsigned type with well-defined behavior
in bit operations than to have to worry about what happens if
a driver mistakenly supplies a negative alignment.

Add an assert that no one was trying to use sectors to get a
write zeroes larger than 2G, and therefore that a later conversion
to bytes won't be impacted by keeping the limit at 32 bits.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-06-08 10:21:08 +02:00
Laurent Vivier
c41a73ffaf qed: Use DIV_ROUND_UP
Replace (((n) + (d) - 1) /(d)) by DIV_ROUND_UP(n,d).

This patch is the result of coccinelle script
scripts/coccinelle/round.cocci

CC: qemu-block@nongnu.org
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-06-07 18:19:24 +03:00
Paolo Bonzini
58369e22cf qemu-common: stop including qemu/bswap.h from qemu-common.h
Move it to the actual users.  There are still a few includes of
qemu/bswap.h in headers; removing them is left for future work.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-19 16:42:28 +02:00
Fam Zheng
c9e9e9c66c block: Drop superfluous invalidating bs->file from drivers
Now they are invalidated by the block layer, so it's not necessary to
do this in block drivers' implementations of .bdrv_invalidate_cache.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:09 +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
72e775c7d9 block: Always set writeback mode in blk_new_open()
All callers of blk_new_open() either don't rely on the WCE bit set after
blk_new_open() because they explicitly set it anyway, or they pass
BDRV_O_CACHE_WB unconditionally.

This patch changes blk_new_open() so that it always enables writeback
mode and asserts that BDRV_O_CACHE_WB is clear. For those callers that
used to pass BDRV_O_CACHE_WB unconditionally, the flag is removed now.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-03-30 12:16:01 +02:00
Rutuja Shah
73bcb24d93 Replaced get_tick_per_sec() by NANOSECONDS_PER_SECOND
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: Rutuja Shah <rutu.shah.26@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:17 +01:00
Markus Armbruster
da34e65cb4 include/qemu/osdep.h: Don't include qapi/error.h
Commit 57cb38b 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: Markus Armbruster <armbru@redhat.com>
[Fix compilation without the spice devel packages. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:15 +01:00
Max Reitz
efaa7c4eeb blockdev: Split monitor reference from BB creation
Before this patch, blk_new() automatically assigned a name to the new
BlockBackend and considered it referenced by the monitor. This patch
removes the implicit monitor_add_blk() call from blk_new() (and
consequently the monitor_remove_blk() call from blk_delete(), too) and
thus blk_new() (and related functions) no longer take a BB name
argument.

In fact, there is only a single point where blk_new()/blk_new_open() is
called and the new BB is monitor-owned, and that is in blockdev_init().
Besides thus relieving us from having to invent names for all of the BBs
we use in qemu-img, this fixes a bug where qemu cannot create a new
image if there already is a monitor-owned BB named "image".

If a BB and its BDS tree are created in a single operation, as of this
patch the BDS tree will be created before the BB is given a name
(whereas it was the other way around before). This results in minor
change to the output of iotest 087, whose reference output is amended
accordingly.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-17 15:47:56 +01:00
Max Reitz
a55448b368 qapi: Drop QERR_UNKNOWN_BLOCK_FORMAT_FEATURE
Just specifying a custom string is simpler in basically all places that
used it, and in addition, specifying the BB or node name is something we
generally do not do in other error messages when opening a BDS, so we
should not do it here.

This changes the output for iotest 036 (to the better, in my opinion),
so the reference output needs to be changed accordingly.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-17 15:47:56 +01:00
Stefan Hajnoczi
1f3ddfcb25 Revert "qed: Implement .bdrv_drain"
This reverts commit df9a681dc9.

Note that commit df9a681dc9 included some
unrelated hunks, possibly due to a merge failure or an overlooked
squash.  This only reverts the qed .bdrv_drain() implementation.

The qed .bdrv_drain() implementation is unsafe and can lead to a double
request completion.

Paolo Bonzini reports:
"The problem is that bdrv_qed_drain calls qed_plug_allocating_write_reqs
unconditionally, but this is not correct if an allocating write is
queued.  In this case, qed_unplug_allocating_write_reqs will restart the
allocating write and possibly cause it to complete.  The aiocb however
is still in use for the L2/L1 table writes, and will then be completed
again as soon as the table writes are stable."

For QEMU 2.6 we can simply revert this commit.  A full solution for the
qed need check timer may be added if the bdrv_drain() implementation is
extended.

Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1457431876-8475-1-git-send-email-stefanha@redhat.com
2016-03-17 09:50:14 +00:00
Kevin Wolf
8a56fdadaf qed: Use BB functions in .bdrv_create()
All users of the block layers are supposed to go through a BlockBackend.
The .bdrv_create() implementation is one such user, so this patch
converts it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-14 16:46:43 +01:00
Fam Zheng
53f1dfd1ff qed: Assign bs->file->bs to file in bdrv_qed_co_get_block_status
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 1453780743-16806-8-git-send-email-famz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-02-02 17:50:47 +01:00
Fam Zheng
67a0fd2a9b block: Add "file" output parameter to block status query functions
The added parameter can be used to return the BDS pointer which the
valid offset is referring to. Its value should be ignored unless
BDRV_BLOCK_OFFSET_VALID in ret is set.

Until block drivers fill in the right value, let's clear it explicitly
right before calling .bdrv_get_block_status.

The "bs->file" condition in bdrv_co_get_block_status is kept now to keep iotest
case 102 passing, and will be fixed once all drivers return the right file
pointer.

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 1453780743-16806-2-git-send-email-famz@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-02-02 17:50:47 +01:00
Kevin Wolf
04c01a5c8f block: Rename BDRV_O_INCOMING to BDRV_O_INACTIVE
Instead of covering only the state of images on the migration
destination before the migration is completed, the flag will also cover
the state of images on the migration source after completion. This
common state implies that the image is technically still open, but no
writes will happen and any cached contents will be reloaded from disk if
and when the image leaves this state.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-01-20 13:36:23 +01:00
Peter Maydell
80c71a241a block: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-01-20 13:36:23 +01:00
Markus Armbruster
e43bfd9c87 error: Use error_prepend() where it makes obvious sense
Done with this Coccinelle semantic patch

    @@
    expression FMT, E1, E2;
    expression list ARGS;
    @@
    -    error_setg(E1, FMT, ARGS, error_get_pretty(E2));
    +    error_propagate(E1, E2);/*###*/
    +    error_prepend(E1, FMT/*@@@*/, ARGS);

followed by manual cleanup, first because I can't figure out how to
make Coccinelle transform strings, and second to get rid of now
superfluous error_propagate().

We now use or propagate the original error whole instead of just its
message obtained with error_get_pretty().  This avoids suppressing its
hint (see commit 50b7b00), but I can't see how the errors touched in
this commit could come with hints.  It also improves the message
printed with &error_abort when we screw up (see commit 1e9b65b).

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-01-13 15:16:17 +01:00
Fam Zheng
df9a681dc9 qed: Implement .bdrv_drain
The "need_check_timer" is used to clear the "NEED_CHECK" flag in the
image header after a grace period once metadata update has finished. In
compliance to the bdrv_drain semantics we should make sure it remains
deleted once .bdrv_drain is called.

We cannot reuse qed_need_check_timer_cb because here it doesn't satisfy
the assertion.  Do the "plug" and "flush" calls manually.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1447064214-29930-10-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-11-12 16:22:43 +01:00
Kevin Wolf
8e419aefa0 block: Remove bdrv_swap()
bdrv_swap() is unused now. Remove it and all functions that have
no other users than bdrv_swap(). In particular, this removes the
.bdrv_rebind callbacks from block drivers.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-10-16 15:34:30 +02:00
Kevin Wolf
760e006384 block: Convert bs->backing_hd to BdrvChild
This is the final step in converting all of the BlockDriverState
pointers that block drivers use to BdrvChild.

After this patch, bs->children contains the full list of child nodes
that are referenced by a given BDS, and these children are only
referenced through BdrvChild, so that updating the pointer in there is
enough for changing edges in the graph.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-10-16 15:34:29 +02:00
Kevin Wolf
9a4f4c3156 block: Convert bs->file to BdrvChild
This patch removes the temporary duplication between bs->file and
bs->file_child by converting everything to BdrvChild.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-10-16 15:34:29 +02:00
Max Reitz
6ebf9aa2ef block: Drop drv parameter from bdrv_open()
Now that this parameter is effectively unused, we can drop it and just
pass NULL on to bdrv_open_inherit().

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-09-14 16:51:36 +02:00
Markus Armbruster
c6bd8c706a qerror: Clean up QERR_ macros to expand into a single string
These macros expand into error class enumeration constant, comma,
string.  Unclean.  Has been that way since commit 13f59ae.

The error class is always ERROR_CLASS_GENERIC_ERROR since the previous
commit.

Clean up as follows:

* Prepend every use of a QERR_ macro by ERROR_CLASS_GENERIC_ERROR, and
  delete it from the QERR_ macro.  No change after preprocessing.

* Rewrite error_set(ERROR_CLASS_GENERIC_ERROR, ...) into
  error_setg(...).  Again, no change after preprocessing.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-22 18:20:40 +02:00
Alberto Garcia
81e5f78a9f block: use bdrv_get_device_or_node_name() in error messages
There are several error messages that identify a BlockDriverState by
its device name. However those errors can be produced in nodes that
don't have a device name associated.

In those cases we should use bdrv_get_device_or_node_name() to fall
back to the node name and produce a more meaningful message. The
messages are also updated to use the more generic term 'node' instead
of 'device'.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 9823a1f0514fdb0692e92868661c38a9e00a12d6.1428485266.git.berto@igalia.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28 15:36:09 +02:00
Stefan Hajnoczi
786a4ea82e Convert (ffs(val) - 1) to ctz32(val)
This commit was generated mechanically by coccinelle from the following
semantic patch:

@@
expression val;
@@
- (ffs(val) - 1)
+ ctz32(val)

The call sites have been audited to ensure the ffs(0) - 1 == -1 case
never occurs (due to input validation, asserts, etc).  Therefore we
don't need to worry about the fact that ctz32(0) == 32.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1427124571-28598-5-git-send-email-stefanha@redhat.com
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28 15:36:08 +02:00
Stefan Hajnoczi
0adfa1ed65 qed: check for header size overflow
Header size is denoted in clusters.  The maximum cluster size is 64 MB
but there is no limit on header size.  Check for uint32_t overflow in
case the header size field has a whacky value.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1421065893-18875-2-git-send-email-stefanha@redhat.com
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-02-06 17:24:21 +01:00
Markus Armbruster
097310b53e block: Rename BlockDriverCompletionFunc to BlockCompletionFunc
I'll use it with block backends shortly, and the name is going to fit
badly there.  It's a block layer thing anyway, not just a block driver
thing.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20 13:41:27 +02:00
Markus Armbruster
7c84b1b831 block: Rename BlockDriverAIOCB* to BlockAIOCB*
I'll use BlockDriverAIOCB with block backends shortly, and the name is
going to fit badly there.  It's a block layer thing anyway, not just a
block driver thing.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20 13:41:27 +02:00
Markus Armbruster
bfb197e0d9 block: Eliminate BlockDriverState member device_name[]
device_name[] can become non-empty only in bdrv_new_root() and
bdrv_move_feature_fields().  The latter is used only to undo damage
done by bdrv_swap().  The former is called only by blk_new_with_bs().
Therefore, when a BlockDriverState's device_name[] is non-empty, then
it's been created with a BlockBackend, and vice versa.  Furthermore,
blk_new_with_bs() keeps the two names equal.

Therefore, device_name[] is redundant.  Eliminate it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20 13:41:26 +02:00
Fam Zheng
8007429a99 block: Rename qemu_aio_release -> qemu_aio_unref
Suggested-by: Benoît Canet <benoit.canet@irqsave.net>
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22 11:39:17 +01:00
Fam Zheng
533ffb17a5 qed: Drop qed_aiocb_info.cancel
Also drop the now unused ->finished field.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22 11:39:11 +01:00
Hu Tao
c2eb918e32 block: round up file size to nearest sector
Currently the file size requested by user is rounded down to nearest
sector, causing the actual file size could be a bit less than the size
user requested. Since some formats (like qcow2) record virtual disk
size in bytes, this can make the last few bytes cannot be accessed.

This patch fixes it by rounding up file size to nearest sector so that
the actual file size is no less than the requested file size.

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-12 15:43:06 +02:00
Kevin Wolf
4f4896db5f qed: Handle failure for potentially large allocations
Some code in the block layer makes potentially huge allocations. Failure
is not completely unexpected there, so avoid aborting qemu and handle
out-of-memory situations gracefully.

This patch addresses the allocations in the qed block driver.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-08-15 15:07:15 +02:00
Kevin Wolf
3baca89139 block: Add Error argument to bdrv_refresh_limits()
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-07-18 13:18:43 +01:00
Kevin Wolf
f06ee3d4aa qed: Make qiov match request size until backing file EOF
If a QED image has a shorter backing file and a read request to
unallocated clusters goes across EOF of the backing file, the backing
file sees a shortened request and the rest is filled with zeros.
However, the original too long qiov was used with the shortened request.

This patch makes the qiov size match the request size, avoiding a
potential buffer overflow in raw-posix.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2014-07-14 12:03:20 +02:00
Chunyan Liu
4ab1559085 qemu-img create: add 'nocow' option
Add 'nocow' option so that users could have a chance to set NOCOW flag to
newly created files. It's useful on btrfs file system to enhance performance.

Btrfs has low performance when hosting VM images, even more when the guest
in those VM are also using btrfs as file system. One way to mitigate this bad
performance is to turn off COW attributes on VM files. Generally, there are
two ways to turn off NOCOW on btrfs: a) by mounting fs with nodatacow, then
all newly created files will be NOCOW. b) per file. Add the NOCOW file
attribute. It could only be done to empty or new files.

This patch tries the second way, according to the option, it could add NOCOW
per file.

For most block drivers, since the create file step is in raw-posix.c, so we
can do setting NOCOW flag ioctl in raw-posix.c only.

But there are some exceptions, like block/vpc.c and block/vdi.c, they are
creating file by calling qemu_open directly. For them, do the same setting
NOCOW flag ioctl work in them separately.

[Fixed up 082.out due to the new 'nocow' creation option
--Stefan]

Signed-off-by: Chunyan Liu <cyliu@suse.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-07-01 10:15:12 +02:00
Kevin Wolf
8ee79e707a block: Catch backing files assigned to non-COW drivers
Since we parse backing.* options to add a backing file from the command
line when the driver didn't assign one, it has been possible to have a
backing file for e.g. raw images (it just was never accessed).

This is obvious nonsense and should be rejected.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2014-06-26 13:51:01 +02:00
Chunyan Liu
c282e1fdf7 cleanup QEMUOptionParameter
Now that all backend drivers are using QemuOpts, remove all
QEMUOptionParameter related codes.

Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
Signed-off-by: Chunyan Liu <cyliu@suse.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-06-16 17:23:21 +08:00
Chunyan Liu
7ab74849a5 qed.c: replace QEMUOptionParameter with QemuOpts
One extra change is to define QED_DEFAULT_CLUSTER_SIZE = 65536 instead
of 64 * 1024; because:
according to existing create_options, "cluster size" has default value =
QED_DEFAULT_CLUSTER_SIZE, after switching to create_opts, this has to be
stringized and set to .def_value_str. That is,
  .def_value_str = stringify(QED_DEFAULT_CLUSTER_SIZE),
so the QED_DEFAULT_CLUSTER_SIZE could not be a expression.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
Signed-off-by: Chunyan Liu <cyliu@suse.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-06-16 17:23:21 +08:00
Chunyan Liu
83d0521a1e change block layer to support both QemuOpts and QEMUOptionParamter
Change block layer to support both QemuOpts and QEMUOptionParameter.
After this patch, it will change backend drivers one by one. At the end,
QEMUOptionParameter will be removed and only QemuOpts is kept.

Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
Signed-off-by: Chunyan Liu <cyliu@suse.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-06-16 17:23:20 +08:00
Stefan Hajnoczi
a8c868c386 qed: use BlockDriverState's AioContext
Drop the assumption that we're using the main AioContext.  Convert
qemu_bh_new() to aio_bh_new() and qemu_aio_wait() to aio_poll() so we're
using the BlockDriverState's AioContext.

Implement .bdrv_detach/attach_aio_context() interfaces to move the
QED_F_NEED_CHECK timer from the old AioContext to the new one.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-06-04 09:56:11 +02:00
Aakriti Gupta
5ff679b47d convert fprintf() calls to error_setg() in block/qed.c:bdrv_qed_create()
This patch converts fprintf() calls to error_setg() in block/qed.c:bdrv_qed_create()
(error_setg() is part of error reporting API in include/qapi/error.h)

Signed-off-by: Aakriti Gupta <aakritty@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-04-22 11:57:02 +02:00
Kevin Wolf
5a8a30db47 block: Add error handling to bdrv_invalidate_cache()
If it returns an error, the migrated VM will not be started, but qemu
exits with an error message.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-03-19 09:39:41 +01:00
Kevin Wolf
3456a8d185 block: Update image size in bdrv_invalidate_cache()
After migration has completed, we call bdrv_invalidate_cache() so that
drivers which cache some data drop their stale copy of the data and
reread it from the image file to get a new version of data that the
source modified while the migration was running.

Reloading metadata from the image file is useless, though, if the size
of the image file stays stale (this is a value that is cached for all
image formats in block.c). Reads from (meta)data after the old EOF
return only zeroes, causing image corruption.

We need to update bs->total_sectors in all layers that could potentially
have changed their size (i.e. backing files are not a concern - if they
are changed, we're in bigger trouble)

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-03-13 14:23:27 +01:00
Paolo Bonzini
76abe4071d block: do not abuse EMEDIUMTYPE
Returning "Wrong medium type" for an image that does not have a valid
header is a bit weird.  Improve the error by mentioning what format
was trying to open it.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-21 21:02:24 +01:00