Commit Graph

54413 Commits

Author SHA1 Message Date
KONRAD Frederic
7cc2298c46 introduce mmio_interface
This introduces mmio_interface object which contains a MemoryRegion
and can be hotplugged/hotunplugged.

Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2017-06-27 15:09:15 +02:00
KONRAD Frederic
ed03d749f3 qdev: add MemoryRegion property
We need to pass a pointer to a MemoryRegion for mmio_interface.
So this just adds that.

Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2017-06-27 15:09:15 +02:00
KONRAD Frederic
71b9a45330 cputlb: fix the way get_page_addr_code fills the tlb
get_page_addr_code(..) does a cpu_ldub_code to fill the tlb:
This can lead to some side effects if a device is mapped at this address.

So this patch replaces the cpu_memory_ld by a tlb_fill.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2017-06-27 15:09:15 +02:00
KONRAD Frederic
f2553f0489 cputlb: move get_page_addr_code
This just moves the code before VICTIM_TLB_HIT macro definition
so we can use it.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2017-06-27 15:09:14 +02:00
KONRAD Frederic
3416343255 cputlb: cleanup get_page_addr_code to use VICTIM_TLB_HIT
This replaces env1 and page_index variables by env and index
so we can use VICTIM_TLB_HIT macro later.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2017-06-27 15:09:04 +02:00
Peter Maydell
054914f646 Block layer patches
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block layer patches

# gpg: Signature made Mon 26 Jun 2017 14:07:32 BST
# gpg:                using RSA key 0x7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74  56FE 7F09 B272 C88F 2FD6

* remotes/kevin/tags/for-upstream: (60 commits)
  qemu-img: don't shadow opts variable in img_dd()
  block: Do not strcmp() with NULL uri->scheme
  blkverify: Catch bs->exact_filename overflow
  blkdebug: Catch bs->exact_filename overflow
  fix: avoid an infinite loop or a dangling pointer problem in img_commit
  block: change variable names in BlockDriverState
  block: Remove bdrv_aio_readv/writev/flush()
  qed: Use bdrv_co_* for coroutine_fns
  qed: Add coroutine_fn to I/O path functions
  qed: Use a coroutine for need_check_timer
  qed: Simplify request handling
  qed: Use CoQueue for serialising allocations
  qed: Implement .bdrv_co_readv/writev
  qed: Remove recursion in qed_aio_next_io()
  qed: Remove ret argument from qed_aio_next_io()
  qed: Add return value to qed_aio_read/write_data()
  qed: Add return value to qed_aio_write_inplace/alloc()
  qed: Add return value to qed_aio_write_cow()
  qed: Add return value to qed_aio_write_main()
  qed: Add return value to qed_aio_write_l2_update()
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-06-26 15:38:29 +01:00
Kevin Wolf
704e41ba78 Block patches for the block queue
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Merge remote-tracking branch 'mreitz/tags/pull-block-2017-06-26' into queue-block

Block patches for the block queue

# gpg: Signature made Mon Jun 26 14:56:24 2017 CEST
# gpg:                using RSA key 0xF407DB0061D5CF40
# gpg: Good signature from "Max Reitz <mreitz@redhat.com>"
# Primary key fingerprint: 91BE B60A 30DB 3E88 57D1  1829 F407 DB00 61D5 CF40

* mreitz/tags/pull-block-2017-06-26:
  qemu-img: don't shadow opts variable in img_dd()
  block: Do not strcmp() with NULL uri->scheme
  blkverify: Catch bs->exact_filename overflow
  blkdebug: Catch bs->exact_filename overflow
  fix: avoid an infinite loop or a dangling pointer problem in img_commit
  block: change variable names in BlockDriverState

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-06-26 14:57:27 +02:00
Stefan Hajnoczi
2a24570909 qemu-img: don't shadow opts variable in img_dd()
It's confusing when two different variables have the same name in one
function.

Cc: Reda Sallahi <fullmanet@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20170619150002.3033-1-stefanha@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-06-26 14:54:46 +02:00
Max Reitz
f69165a8fe block: Do not strcmp() with NULL uri->scheme
uri_parse(...)->scheme may be NULL. In fact, probably every field may be
NULL, and the callers do test this for all of the other fields but not
for scheme (except for block/gluster.c; block/vxhs.c does not access
that field at all).

We can easily fix this by using g_strcmp0() instead of strcmp().

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170613205726.13544-1-mreitz@redhat.com
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-06-26 14:54:46 +02:00
Max Reitz
05cc758a3d blkverify: Catch bs->exact_filename overflow
The bs->exact_filename field may not be sufficient to store the full
blkverify node filename. In this case, we should not generate a filename
at all instead of an unusable one.

Cc: qemu-stable@nongnu.org
Reported-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170613172006.19685-3-mreitz@redhat.com
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-06-26 14:54:46 +02:00
Max Reitz
de81d72d3d blkdebug: Catch bs->exact_filename overflow
The bs->exact_filename field may not be sufficient to store the full
blkdebug node filename. In this case, we should not generate a filename
at all instead of an unusable one.

Cc: qemu-stable@nongnu.org
Reported-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170613172006.19685-2-mreitz@redhat.com
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-06-26 14:54:46 +02:00
sochin.jiang
4172a00373 fix: avoid an infinite loop or a dangling pointer problem in img_commit
img_commit could fall into an infinite loop calling run_block_job() if
its blockjob fails on any I/O error, fix this already known problem.

Signed-off-by: sochin.jiang <sochin.jiang@huawei.com>
Message-id: 1497509253-28941-1-git-send-email-sochin.jiang@huawei.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-06-26 14:54:46 +02:00
Manos Pitsidianakis
f5a5ca7969 block: change variable names in BlockDriverState
Change the 'int count' parameter in *pwrite_zeros, *pdiscard related
functions (and some others) to 'int bytes', as they both refer to bytes.
This helps with code legibility.

Signed-off-by: Manos Pitsidianakis <el13635@mail.ntua.gr>
Message-id: 20170609101808.13506-1-el13635@mail.ntua.gr
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-06-26 14:54:46 +02:00
Kevin Wolf
c5f1ad429c block: Remove bdrv_aio_readv/writev/flush()
These functions are unused now.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:15 +02:00
Kevin Wolf
0f714ec706 qed: Use bdrv_co_* for coroutine_fns
All functions that are marked coroutine_fn can directly call the
bdrv_co_* version of functions instead of going through the wrapper.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Manos Pitsidianakis <el13635@mail.ntua.gr>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:15 +02:00
Kevin Wolf
87f0d88261 qed: Add coroutine_fn to I/O path functions
Now that we stay in coroutine context for the whole request when doing
reads or writes, we can add coroutine_fn annotations to many functions
that can do I/O or yield directly.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:15 +02:00
Kevin Wolf
c0e8f98927 qed: Use a coroutine for need_check_timer
This fixes the last place where we degraded from AIO to actual blocking
synchronous I/O requests. Putting it into a coroutine means that instead
of blocking, the coroutine simply yields while doing I/O.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:15 +02:00
Kevin Wolf
48cc565e76 qed: Simplify request handling
Now that we process a request in the same coroutine from beginning to
end and don't drop out of it any more, we can look like a proper
coroutine-based driver and simply call qed_aio_next_io() and get a
return value from it instead of spawning an additional coroutine that
reenters the parent when it's done.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:15 +02:00
Kevin Wolf
0806c3b5dd qed: Use CoQueue for serialising allocations
Now that we're running in coroutine context, the ad-hoc serialisation
code (which drops a request that has to wait out of coroutine context)
can be replaced by a CoQueue.

This means that when we resume a serialised request, it is running in
coroutine context again and its I/O isn't blocking any more.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:15 +02:00
Kevin Wolf
89f89709c7 qed: Implement .bdrv_co_readv/writev
Most of the qed code is now synchronous and matches the coroutine model.
One notable exception is the serialisation between requests which can
still schedule a callback. Before we can replace this with coroutine
locks, let's convert the driver's external interfaces to the coroutine
versions.

We need to be careful to handle both requests that call the completion
callback directly from the calling coroutine (i.e. fully synchronous
code) and requests that involve some callback, so that we need to yield
and wait for the completion callback coming from outside the coroutine.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Manos Pitsidianakis <el13635@mail.ntua.gr>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:15 +02:00
Kevin Wolf
018598747c qed: Remove recursion in qed_aio_next_io()
Instead of calling itself recursively as the last thing, just convert
qed_aio_next_io() into a loop.

This patch is best reviewed with 'git show -w' because most of it is
just whitespace changes.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:15 +02:00
Kevin Wolf
dddf8db10b qed: Remove ret argument from qed_aio_next_io()
All callers pass ret = 0, so we can just remove it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
0596be7e6a qed: Add return value to qed_aio_read/write_data()
Don't recurse into qed_aio_next_io() and qed_aio_complete() here, but
just return an error code and let the caller handle it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
d6daddcdeb qed: Add return value to qed_aio_write_inplace/alloc()
Don't recurse into qed_aio_next_io() and qed_aio_complete() here, but
just return an error code and let the caller handle it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
a101341aa0 qed: Add return value to qed_aio_write_cow()
Don't recurse into qed_aio_next_io() and qed_aio_complete() here, but
just return an error code and let the caller handle it.

While refactoring qed_aio_write_alloc() to accomodate the change,
qed_aio_write_zero_cluster() ended up with a single line, so I chose to
inline that line and remove the function completely.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
eaf0bc56f5 qed: Add return value to qed_aio_write_main()
Don't recurse into qed_aio_next_io() and qed_aio_complete() here, but
just return an error code and let the caller handle it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
88d2dd72bc qed: Add return value to qed_aio_write_l2_update()
Don't recurse into qed_aio_next_io() and qed_aio_complete() here, but
just return an error code and let the caller handle it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
fb18de21e0 qed: Add return value to qed_aio_write_l1_update()
Don't recurse into qed_aio_next_io() and qed_aio_complete() here, but
just return an error code and let the caller handle it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
fae25ac7bd qed: Inline qed_commit_l2_update()
qed_commit_l2_update() is unconditionally called at the end of
qed_aio_write_l1_update(). Inline it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
a4d8f1aee1 qed: Make qed_aio_write_main() synchronous
Note that this code is generally not running in coroutine context, so
this is an actual blocking synchronous operation. We'll fix this in a
moment.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
3e248cdcd9 qed: Make qed_aio_read_data() synchronous
Note that this code is generally not running in coroutine context, so
this is an actual blocking synchronous operation. We'll fix this in a
moment.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
453e53e2a1 qed: Remove callback from qed_write_table()
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
29470d11bf qed: Remove GenericCB
The GenericCB infrastructure isn't used any more. Remove it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
602b57fba4 qed: Make qed_write_table() synchronous
Note that this code is generally not running in coroutine context, so
this is an actual blocking synchronous operation. We'll fix this in a
moment.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
f13d712bb2 qed: Remove callback from qed_write_header()
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
7076309aef qed: Make qed_write_header() synchronous
Note that this code is generally not running in coroutine context, so
this is an actual blocking synchronous operation. We'll fix this in a
moment.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
b4ac32f34f qed: Remove callback from qed_copy_from_backing_file()
With this change, qed_aio_write_prefill() and qed_aio_write_postfill()
collapse into a single function. This is reflected by a rename of the
combined function to qed_aio_write_cow().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
0f7aa24d2c qed: Make qed_copy_from_backing_file() synchronous
Note that this code is generally not running in coroutine context, so
this is an actual blocking synchronous operation. We'll fix this in a
moment.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
e85c528142 qed: Make qed_read_backing_file() synchronous
Note that this code is generally not running in coroutine context, so
this is an actual blocking synchronous operation. We'll fix this in a
moment.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
0f21b7a1b7 qed: Remove callback from qed_find_cluster()
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
a8165d2d66 qed: Remove callback from qed_read_l2_table()
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
f6513529c6 qed: Remove callback from qed_read_table()
Instead of passing the return value to a callback, return it to the
caller so that the callback can be inlined there.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
11273076e9 qed: Make qed_read_table() synchronous
Note that this code is generally not running in coroutine context, so
this is an actual blocking synchronous operation. We'll fix this in a
moment.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Kevin Wolf
3b7cd9fd8f qed: Use bottom half to resume waiting requests
The qed driver serialises allocating write requests. When the active
allocation is finished, the AIO callback is called, but after this, the
next allocating request is immediately processed instead of leaving the
coroutine. Resuming another allocation request in the same request
coroutine means that the request now runs in the wrong coroutine.

The following is one of the possible effects of this: The completed
request will generally reenter its request coroutine in a bottom half,
expecting that it completes the request in bdrv_driver_pwritev().
However, if the second request actually yielded before leaving the
coroutine, the reused request coroutine is in an entirely different
place and is reentered prematurely. Not a good idea.

Let's make sure that we exit the coroutine after completing the first
request by resuming the next allocating request only with a bottom
half.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:14 +02:00
Alberto Garcia
24990c5b95 qcow2: Use offset_into_cluster() and offset_to_l2_index()
We already have functions for doing these calculations, so let's use
them instead of doing everything by hand. This makes the code a bit
more readable.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-06-26 14:51:13 +02:00
Alberto Garcia
ee22a9d869 qcow2: Merge the writing of the COW regions with the guest data
If the guest tries to write data that results on the allocation of a
new cluster, instead of writing the guest data first and then the data
from the COW regions, write everything together using one single I/O
operation.

This can improve the write performance by 25% or more, depending on
several factors such as the media type, the cluster size and the I/O
request size.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-06-26 14:51:13 +02:00
Alberto Garcia
86b862c431 qcow2: Pass a QEMUIOVector to do_perform_cow_{read,write}()
Instead of passing a single buffer pointer to do_perform_cow_write(),
pass a QEMUIOVector. This will allow us to merge the write requests
for the COW regions and the actual data into a single one.

Although do_perform_cow_read() does not strictly need to change its
API, we're doing it here as well for consistency.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-06-26 14:51:13 +02:00
Alberto Garcia
b3cf1c7cf8 qcow2: Allow reading both COW regions with only one request
Reading both COW regions requires two separate requests, but it's
perfectly possible to merge them and perform only one. This generally
improves performance, particularly on rotating disk drives. The
downside is that the data in the middle region is read but discarded.

This patch takes a conservative approach and only merges reads when
the size of the middle region is <= 16KB.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-06-26 14:51:13 +02:00
Alberto Garcia
672f0f2c4b qcow2: Split do_perform_cow() into _read(), _encrypt() and _write()
This patch splits do_perform_cow() into three separate functions to
read, encrypt and write the COW regions.

perform_cow() can now read both regions first, then encrypt them and
finally write them to disk. The memory allocation is also done in
this function now, using one single buffer large enough to hold both
regions.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-06-26 14:51:13 +02:00
Alberto Garcia
99450c6fb9 qcow2: Make perform_cow() call do_perform_cow() twice
Instead of calling perform_cow() twice with a different COW region
each time, call it just once and make perform_cow() handle both
regions.

This patch simply moves code around. The next one will do the actual
reordering of the COW operations.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-06-26 14:51:13 +02:00