block: push recursive flushing up from drivers

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

Merge remote-tracking branch 'stefanha/trivial-patches' into staging

* stefanha/trivial-patches:
configure: Quote the configure args printed in config.log
osdep: Remove local definition of macro

Merge remote-tracking branch 'stefanha/trivial-patches' into staging

* stefanha/trivial-patches:
configure: Quote the configure args printed in config.log
osdep: Remove local definition of macro offsetof
libcacard: Spelling and grammar fixes in documentation
Spelling fixes in comments (it's -> its)
vnc: Add break statement
libcacard: Use format specifier %u instead of %d for unsigned values
Fix sign of sscanf format specifiers
block/vmdk: Fix warning from splint (comparision of unsigned value)
qmp: Fix spelling fourty -> forty
qom: Fix spelling in documentation
sh7750: Remove redundant 'struct' from MemoryRegionOps

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block/vmdk: Fix warning from splint (comparision of unsigned value)

l1_entry_sectors will never be less than 0.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Stefan Hajnoczi <stefanha@

block/vmdk: Fix warning from splint (comparision of unsigned value)

l1_entry_sectors will never be less than 0.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>

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Merge remote-tracking branch 'kwolf/for-anthony' into staging

block: convert qcow2, qcow2, and vmdk to .bdrv_co_is_allocated()

The qcow2, qcow, and vmdk block drivers are based on coroutines. They have a
coroutine mutex which protects internal state. We can

block: convert qcow2, qcow2, and vmdk to .bdrv_co_is_allocated()

The qcow2, qcow, and vmdk block drivers are based on coroutines. They have a
coroutine mutex which protects internal state. We can convert the
.bdrv_is_allocated() function to .bdrv_co_is_allocated() by holding the mutex
around the cluster lookup operation.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

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Merge remote-tracking branch 'kwolf/block-stable' into staging

vmdk: Add migration blocker

VMDK caches L2 tables. For migration to work, they would have to be
invalidated. Block migration for now.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>

Include zlib.h using #include <>

zlib.h is not a local include file, therefore it should be included
using <> instead of "".

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Anthony Liguo

Include zlib.h using #include <>

zlib.h is not a local include file, therefore it should be included
using <> instead of "".

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

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Merge remote-tracking branch 'kwolf/block-stable' into staging

block: Rename bdrv_co_flush to bdrv_co_flush_to_disk

There are two different types of flush that you can do: Flushing one level up
to the OS (i.e. writing data to the host page cache) or flushing it

block: Rename bdrv_co_flush to bdrv_co_flush_to_disk

There are two different types of flush that you can do: Flushing one level up
to the OS (i.e. writing data to the host page cache) or flushing it all the way
down to the disk. The existing functions flush to the disk, reflect this in the
function name.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>

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Merge remote-tracking branch 'kwolf/for-anthony' into staging

Conflicts:
block/vmdk.c

Merge remote-tracking branch 'stefanha/trivial-patches' into staging

vmdk: Fix possible segfaults

Data we read from the disk isn't necessarily null terminated and may not
contain the string we're looking for. The code needs to be a bit more careful
here.

Signed-off-

vmdk: Fix possible segfaults

Data we read from the disk isn't necessarily null terminated and may not
contain the string we're looking for. The code needs to be a bit more careful
here.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>

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vmdk: Improve error handling

Return the right error values in some more places.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>

vmdk: Fix use of uninitialised value

In error cases, cid is never set.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>

Merge remote-tracking branch 'kwolf/for-anthony' into staging

vmdk: vmdk_read_cid returns garbage if p_name is NULL

Spotted by Clang Analyzer

Signed-off-by: Pavel Borzenkov <pavel.borzenkov@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.co

vmdk: vmdk_read_cid returns garbage if p_name is NULL

Spotted by Clang Analyzer

Signed-off-by: Pavel Borzenkov <pavel.borzenkov@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>

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vmdk: remove unneeded variable assignment

Spotted by Clang Analyzer

Signed-off-by: Pavel Borzenkov <pavel.borzenkov@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>

block: change flush to co_flush

Since coroutine operation is now mandatory, convert all bdrv_flush
implementations to coroutines. For qcow2, this means taking the lock.
Other implementations are si

block: change flush to co_flush

Since coroutine operation is now mandatory, convert all bdrv_flush
implementations to coroutines. For qcow2, this means taking the lock.
Other implementations are simpler and just forward bdrv_flush to the
underlying protocol, so they can avoid the lock.

The bdrv_flush callback is then unused and can be eliminated.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

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block: take lock around bdrv_write implementations

This does the first part of the conversion to coroutines, by
wrapping bdrv_write implementations to take the mutex.

Drivers that implement bdrv_wr

block: take lock around bdrv_write implementations

This does the first part of the conversion to coroutines, by
wrapping bdrv_write implementations to take the mutex.

Drivers that implement bdrv_write rather than bdrv_co_writev can
then benefit from asynchronous operation (at least if the underlying
protocol supports it, which is not the case for raw-win32), even
though they still operate with a bounce buffer.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

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block: take lock around bdrv_read implementations

This does the first part of the conversion to coroutines, by
wrapping bdrv_read implementations to take the mutex.

Drivers that implement bdrv_read

block: take lock around bdrv_read implementations

This does the first part of the conversion to coroutines, by
wrapping bdrv_read implementations to take the mutex.

Drivers that implement bdrv_read rather than bdrv_co_readv can
then benefit from asynchronous operation (at least if the underlying
protocol supports it, which is not the case for raw-win32), even
though they still operate with a bounce buffer.

raw-win32 does not need the lock, because it cannot yield.
nbd also doesn't probably, but better be safe.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

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block: add a CoMutex to synchronous read drivers

The big conversion of bdrv_read/write to coroutines caused the two
homonymous callbacks in BlockDriver to become reentrant. It goes
like this:

1) b

block: add a CoMutex to synchronous read drivers

The big conversion of bdrv_read/write to coroutines caused the two
homonymous callbacks in BlockDriver to become reentrant. It goes
like this:

1) bdrv_read is now called in a coroutine, and calls bdrv_read or
bdrv_pread.

2) the nested bdrv_read goes through the fast path in bdrv_rw_co_entry;

3) in the common case when the protocol is file, bdrv_co_do_readv calls
bdrv_co_readv_em (and from here goes to bdrv_co_io_em), which yields
until the AIO operation is complete;

4) if bdrv_read had been called from a bottom half, the main loop
is free to iterate again: a device model or another bottom half
can then come and call bdrv_read again.

This applies to all four of read/write/flush/discard. It would also
apply to is_allocated, but it is not used from within coroutines:
besides qemu-img.c and qemu-io.c, which operate synchronously, the
only user is the monitor. Copy-on-read will introduce a use in the
block layer, and will require converting it.

The solution is "simply" to convert all drivers to coroutines! We
just need to add a CoMutex that is taken around affected operations.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

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vmdk: clean up open

Move vmdk_parent_open to vmdk_open. There's another path how
vmdk_parent_open can be reached:

vmdk_parse_extents() -> vmdk_open_sparse() -> vmdk_open_vmdk4() ->
vmdk_open

vmdk: clean up open

Move vmdk_parent_open to vmdk_open. There's another path how
vmdk_parent_open can be reached:

vmdk_parse_extents() -> vmdk_open_sparse() -> vmdk_open_vmdk4() ->
vmdk_open_desc_file().

If that can happen, however, the code is bogus. vmdk_parent_open
reads from bs->file:

if (bdrv_pread(bs->file, s->desc_offset, desc, DESC_SIZE) != DESC_SIZE) {

but it is always called with s->desc_offset == 0 and with the same
bs->file. So the data that vmdk_parent_open reads comes always from the
same place, and anyway there is only one place where it can write it,
namely bs->backing_file.

So, if it cannot happen, the patched code is okay.

It is also possible that the recursive call can happen, but only once. In
that case there would still be a bug in vmdk_open_desc_file setting
s->desc_offset = 0, but the patched code is okay.

Finally, in the case where multiple recursive calls can happen the code
would need to be rewritten anyway. It is likely that this would anyway
involve adding several parameters to vmdk_parent_open, and calling it from
vmdk_open_vmdk4.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

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vmdk: fix return values of vmdk_parent_open

While vmdk_open_desc_file (touched by the patch) correctly changed -1
to -EINVAL, vmdk_open did not. Fix it directly in vmdk_parent_open.

Signed-off-by:

vmdk: fix return values of vmdk_parent_open

While vmdk_open_desc_file (touched by the patch) correctly changed -1
to -EINVAL, vmdk_open did not. Fix it directly in vmdk_parent_open.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

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Merge remote-tracking branch 'kwolf/for-anthony' into staging