Commit Graph

110 Commits

Author SHA1 Message Date
Marc-André Lureau 13f1493f82 vpc: use DIV_ROUND_UP
I used the clang-tidy qemu-round check to generate the fix:
https://github.com/elmarco/clang-tools-extra

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2017-08-31 12:29:07 +02:00
Eric Blake 81caa3cc3b vpc: Check failure of bdrv_getlength()
vpc_open() was checking for bdrv_getlength() failure in one, but
not the other, location.

Reported-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-08-11 13:23:40 +02:00
Mark Cave-Ayland c8115f8eb8 block/vpc: fix uninitialised variable compiler warning
Since commit cfc87e00 "block/vpc.c: Handle write failures in
get_image_offset()" older versions of gcc (in this case 4.7) incorrectly
warn that "ret" can be used uninitialised in vpc_co_pwritev().

Setting ret to 0 at the start of vpc_co_pwritev() prevents the warning
in gcc 4.7 and enables compilation with -Werror to succeed.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1500625265-23844-1-git-send-email-mark.cave-ayland@ilande.co.uk
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-07-21 15:00:07 +01:00
Peter Maydell cfc87e00c2 block/vpc.c: Handle write failures in get_image_offset()
Coverity (CID 1355236) points out that get_image_offset() doesn't check that
it actually succeeded in writing the updated block bitmap to the file.
Check the error return from bdrv_pwrite_sync() and propagate an error
response back up to the function which calls get_image_offset() for
a write so that it can return the error to its caller.

get_sector_offset() is only used for reads, but we move it to the
same API for consistency.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-07-18 15:14:35 +02:00
Paolo Bonzini 778b087e51 vpc: make it thread-safe
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20170629132749.997-5-pbonzini@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
2017-07-17 11:28:15 +08:00
Max Reitz 3a691c50f1 block: Add PreallocMode to blk_truncate()
blk_truncate() itself will pass that value to bdrv_truncate(), and all
callers of blk_truncate() just set the parameter to PREALLOC_MODE_OFF
for now.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20170613202107.10125-4-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-07-11 17:45:01 +02:00
Eric Blake d5254033da block: Simplify use of BDRV_BLOCK_RAW
The lone caller that cares about a return of BDRV_BLOCK_RAW
(namely, io.c:bdrv_co_get_block_status) completely replaces the
return value, so there is no point in passing BDRV_BLOCK_DATA.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-07-10 13:18:05 +02:00
Juan Quintela 795c40b8bd migration: Create migration/blocker.h
This allows us to remove lots of includes of migration/migration.h

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-05-17 12:04:59 +02:00
Max Reitz ed3d2ec98a block: Add errp to b{lk,drv}_truncate()
For one thing, this allows us to drop the error message generation from
qemu-img.c and blockdev.c and instead have it unified in
bdrv_truncate().

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170328205129.15138-3-mreitz@redhat.com
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-04-28 16:02:02 +02:00
Kevin Wolf 55880601d8 block: Add BDRV_O_RESIZE for blk_new_open()
blk_new_open() is a convenience function that processes flags rather
than QDict options as a simple way to just open an image file.

In order to keep it convenient in the future, it must automatically
request the necessary permissions. This can easily be inferred from the
flags for read and write, but we need another flag that tells us whether
to get the resize permission.

We can't just always request it because that means that no block jobs
can run on the resulting BlockBackend (which is something that e.g.
qemu-img commit wants to do), but we also can't request it never because
most of the .bdrv_create() implementations call blk_truncate().

The solution is to introduce another flag that is passed by all users
that want to resize the image.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2017-02-28 20:40:36 +01:00
Kevin Wolf 862f215fab block: Request child permissions in format drivers
This makes use of the .bdrv_child_perm() implementation for formats that
we just added. All format drivers expose the permissions they actually
need nows, so that they can be set accordingly and updated when parents
are attached or detached.

The only format not included here is raw, which was already converted
with the other filter drivers.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Acked-by: Fam Zheng <famz@redhat.com>
2017-02-28 20:40:36 +01:00
Kevin Wolf 4e4bf5c42c block: Attach bs->file only during .bdrv_open()
The way that attaching bs->file worked was a bit unusual in that it was
the only child that would be attached to a node which is not opened yet.
Because of this, the block layer couldn't know yet which permissions the
driver would eventually need.

This patch moves the point where bs->file is attached to the beginning
of the individual .bdrv_open() implementations, so drivers already know
what they are going to do with the child. This is also more consistent
with how driver-specific children work.

For a moment, bdrv_open() gets its own BdrvChild to perform image
probing, but instead of directly assigning this BdrvChild to the BDS, it
becomes a temporary one and the node name is passed as an option to the
drivers, so that they can simply use bdrv_open_child() to create another
reference for their own use.

This duplicated child for (the not opened yet) bs is not the final
state, a follow-up patch will change the image probing code to use a
BlockBackend, which is completely independent of bs.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2017-02-24 16:09:23 +01:00
Ashijeet Acharya fe44dc9180 migration: disallow migrate_add_blocker during migration
If a migration is already in progress and somebody attempts
to add a migration blocker, this should rightly fail.

Add an errp parameter and a retcode return value to migrate_add_blocker.

Signed-off-by: John Snow <jsnow@redhat.com>
Signed-off-by: Ashijeet Acharya <ashijeetacharya@gmail.com>
Message-Id: <1484566314-3987-5-git-send-email-ashijeetacharya@gmail.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Acked-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Merged with recent 'Allow invtsc migration' change
2017-01-24 18:00:30 +00:00
Fam Zheng 38440a21fa vpc: Use QEMU UUID API
Previously we conditionally generated footer->uuid, when libuuid was
available. Now that we have a built-in implementation, we can switch to
it.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-Id: <1474432046-325-6-git-send-email-famz@redhat.com>
2016-09-23 11:42:52 +08:00
Kevin Wolf a03ef88f77 block: Convert bdrv_co_preadv/pwritev to BdrvChild
This is the final patch for converting the common I/O path to take
a BdrvChild parameter instead of BlockDriverState.

The completion of this conversion means that all users that perform I/O
on an image need to actually hold a reference (in the form of BdrvChild,
possible as part of a BlockBackend) to that image. This also protects
against inconsistent use of BlockBackend vs. BlockDriverState functions
because direct use of a BlockDriverState isn't possible any more and
blk->root is private for block-backends.c.

In addition, we can now distinguish different users in the I/O path,
and the future op blockers work is going to add assertions based on
permissions stored in BdrvChild.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-05 16:46:27 +02:00
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
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
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 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
Jeff Cody 9c057d0b68 block/vpc: update comments to be compliant w/coding guidelines
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-04-15 17:22:12 +02:00
Jeff Cody 32f6439cf7 block/vpc: set errp in vpc_open
Add more useful error information to failure paths in vpc_open

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-04-15 17:22:12 +02:00
Jeff Cody 66176fc6a7 block/vpc: make checks on max table size a bit more lax
The check on the max_table_size field not being larger than required is
valid, and in accordance with the VHD spec.  However, there have been
VHD images encountered in the wild that have an out-of-spec max table
size that is technically too large.

There is no issue in allowing this larger table size, as we also
later verify that the computed size (used for the pagetable) is
large enough to fit all sectors.  In addition, max_table_entries
is bounds checked against SIZE_MAX and INT_MAX.

Remove the strict check, so that we can accomodate these sorts of
images that are benignly out of spec.

Reported-by: Stefan Hajnoczi <stefanha@redhat.com>
Reported-by: Grant Wu <grantwwu@gmail.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-04-15 17:22:12 +02:00
Jeff Cody c23fb11bbb block/vpc: Use the correct max sector count for VHD images
The old VHD_MAX_SECTORS value is incorrect, and is a throwback
to the CHS calculations.  The VHD specification allows images up to 2040
GiB, which (using 512 byte sectors) corresponds to a maximum number of
sectors of 0xff000000, rather than the old value of 0xfe0001ff.

Update VHD_MAX_SECTORS to reflect the correct value.

Also, update comment references to the actual size limit, and correct
one compare so that we can have sizes up to the limit.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-04-15 17:22:12 +02:00
Jeff Cody bab246db1d block/vpc: use current_size field for XenConverter VHD images
XenConverter VHD images are another VHD image where current_size is
different from the CHS values in the the format header.  Use
current_size as the default, by looking at the creator_app signature
field.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-04-15 17:22:12 +02:00
Stefan Hajnoczi 9bdfb9e8ac vpc: use current_size field for XenServer VHD images
The vpc driver has two methods of determining virtual disk size.  The
correct one to use depends on the software that generated the image
file.  Add the XenServer creator_app signature so that image size is
correctly detected for those images.

Reported-by: Grant Wu <grantwwu@gmail.com>
Reported-by: Spencer Baugh <sbaugh@catern.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-04-15 17:22:12 +02:00
Jeff Cody 0211b9becc block/vpc: set errp in vpc_create
Add more useful error information to failure paths in vpc_create().

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-04-15 17:22:11 +02:00
Paolo Bonzini 40a99aace3 vpc: fix return value check for blk_pwrite
bdrv_pwrite_sync used to return zero or negative error, while blk_pwrite returns
the number of written bytes when successful.  This caused VPC image creation
to fail spectacularly: it wrote the first 512 bytes, and then exited immediately
because of the non-zero answer from blk_pwrite.  But the truly spectacular part
is that it returns a positive value (the 512 that blk_pwrite returned) causing
everyone to believe that it succeeded.

This fixes qemu-iotests with vpc format.

Fixes: b8f45cdf78
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-04-12 18:06:51 +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
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
Kevin Wolf b8f45cdf78 vpc: 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 16:46:44 +01:00
Kevin Wolf 6340472c54 block: Use writeback in .bdrv_create() implementations
There's no reason to use a writethrough cache mode while creating an
image.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-14 16:46:43 +01:00
Jeff Cody fb9245c261 block/vpc: give option to force the current_size field in .bdrv_create
When QEMU creates a VHD image, it goes by the original spec,
calculating the current_size based on the nearest CHS geometry (with an
exception for disks > 127GB).

Apparently, Azure will only allow images that are sized to the nearest
MB, and the current_size as calculated from CHS cannot guarantee that.

Allow QEMU to create images similar to how Hyper-V creates images, by
setting current_size to the specified virtual disk size.  This
introduces an option, force_size, to be passed to the vpc format during
image creation, e.g.:

    qemu-img convert -f raw -o force_size -O vpc test.img test.vhd

When using the "force_size" option, the creator app field used by
QEMU will be "qem2" instead of "qemu", to indicate the difference.
In light of this, we also add parsing of the "qem2" field during
vpc_open.

Bug reference: https://bugs.launchpad.net/qemu/+bug/1490611

Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-14 16:46:42 +01:00
Jeff Cody c540d53ac8 block/vpc: choose size calculation method based on creator_app field
The VHD file format is used by both Virtual PC, and Hyper-V.  However,
how the virtual disk size is calculated varies between the two.

Virtual PC uses the CHS drive parameters to determine the drive size.
Hyper-V, on the other hand, uses the current_size field in the footer
when determining image size.

This is problematic for a few reasons:

* VHD images from Hyper-V, using CHS calculations, will likely be
  trunctated.

* If we just rely always on current_size, then QEMU may have data
  compatibility issues with Virtual PC (we may write too much data
  into a VHD file to be used by Virtual PC, for instance).

* Existing VHD images created by QEMU have used the CHS calculations,
  except for images exceeding the 127GB limit.  We want to remain
  compatible with our own generated images.

Luckily, the VHD specification defines a 'Creator App' field, that is
used to indicate what software created the VHD file.

This patch does two things:

    1. Uses the 'Creator App' field to help determine how to calculate
       size, and

    2. Adds a VPC format option 'force_size_calc', so that the user can
       override the 'Creator App' auto-detection, in case there exist
       VHD images with unknown or contradictory 'Creator App' entries.

N.B.: We currently use the maximum CHS value as an indication to use the
current_size field.  This patch does not change that, even with the
'force_size_calc' option.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-14 16:46:42 +01:00
Fam Zheng 7429e20788 vpc: Assign bs->file->bs to file in vpc_co_get_block_status
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 1453780743-16806-11-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
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
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
Jeff Cody b15deac795 block: vpc - prevent overflow if max_table_entries >= 0x40000000
When we allocate the pagetable based on max_table_entries, we multiply
the max table entry value by 4 to accomodate a table of 32-bit integers.
However, max_table_entries is a uint32_t, and the VPC driver accepts
ranges for that entry over 0x40000000.  So during this allocation:

s->pagetable = qemu_try_blockalign(bs->file, s->max_table_entries * 4);

The size arg overflows, allocating significantly less memory than
expected.

Since qemu_try_blockalign() size argument is size_t, cast the
multiplication correctly to prevent overflow.

The value of "max_table_entries * 4" is used elsewhere in the code as
well, so store the correct value for use in all those cases.

We also check the Max Tables Entries value, to make sure that it is <
SIZE_MAX / 4, so we know the pagetable size will fit in size_t.

Cc: qemu-stable@nongnu.org
Reported-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-07-27 17:19:06 +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
Peter Lieven 304ee9174f block/vpc: remove disabled code from get_sector_offset
The code to check the bitmap for the allocation status of each sector
has been "disabled by reason" ever since the vpc driver existed.

The reason might be that we might end up reading sector by sector
in vpc_read if we really used it. This would be a performance desaster.

The current code would furthermore not work if the disabled parts get
reactivated since vpc_read and vpc_write only use get_sector_offset to
check the allocation status of the first sector of a read/write operation.
This might lead to sectors incorrectly treated as zero in vpc_read and
to sectors getting allocated twice in vpc_write.

Signed-off-by: Peter Lieven <pl@kamp.de>
Message-id: 1425379316-19639-6-git-send-email-pl@kamp.de
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-03-16 12:10:30 -04:00
Peter Lieven 03671ded30 block/vpc: rename footer->size -> footer->current_size
the field is named current size in the spec. Name it accordingly.

Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1425379316-19639-5-git-send-email-pl@kamp.de
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-03-16 12:10:30 -04:00
Peter Lieven 690cbb095a block/vpc: make calculate_geometry spec conform
The VHD spec [1] allows for total_sectors of 65535 x 16 x 255 (~127GB)
represented by a CHS geometry. If total_sectors is greater
than 65535 x 16 x 255 this geometry is set as a maximum.

Qemu, Hyper-V and disk2vhd use this special geometry as an indicator
to use the image current size from the footer as disk size.

This patch changes vpc_create to effectively calculate a CxHxS geometry
for the given image size if possible while rounding up if necessary.
If the image size is too big to be represented in CHS we set the maximum
and write the exact requested image size into the footer.

This partly reverts commit 258d2edb, but leaves support for >127G disks
intact.

[1] http://download.microsoft.com/download/f/f/e/ffef50a5-07dd-4cf8-aaa3-442c0673a029/Virtual%20Hard%20Disk%20Format%20Spec_10_18_06.doc

Signed-off-by: Peter Lieven <pl@kamp.de>
Message-id: 1425379316-19639-4-git-send-email-pl@kamp.de
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-03-16 12:10:30 -04:00
Kevin Wolf 0444dceee4 vpc: Ignore geometry for large images
The CHS calculation as done per the VHD spec imposes a maximum image
size of ~127 GB. Real VHD images exist that are larger than that.

Apparently there are two separate non-standard ways to achieve this:
You could use more heads than the spec does - this is the option that
qemu-img create chooses.

However, other images exist where the geometry is set to the maximum
(65535/16/255), but the actual image size is larger. Until now, such
images are truncated at 127 GB when opening them with qemu.

This patch changes the vpc driver to ignore geometry in this case and
only trust the size field in the header.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
[PL: Fixed maximum geometry in the commit msg]
Signed-off-by: Peter Lieven <pl@kamp.de>
Message-id: 1425379316-19639-3-git-send-email-pl@kamp.de
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-03-16 12:10:30 -04:00
Peter Lieven 2ec711dcd4 block/vpc: optimize vpc_co_get_block_status
*pnum can't be greater than s->block_size / BDRV_SECTOR_SIZE for allocated
sectors since there is always a bitmap in between.

Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1425379316-19639-2-git-send-email-pl@kamp.de
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-03-16 12:10:30 -04:00
Kevin Wolf 0cc8488706 vpc: Implement bdrv_co_get_block_status()
This implements bdrv_co_get_block_status() for VHD images. This can
significantly speed up qemu-img convert operation because only with this
function implemented sparseness can be considered. (Before, converting a
1 TB empty image took several minutes for me, now it's instantaneous.)

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2015-03-09 11:11:59 +01:00
Kevin Wolf 3f3f20dcd3 vpc: Fix size in fixed image creation
If total_sectors is rounded to match the geometry, total_size needs to
be changed as well. Otherwise we end up with an image whose geometry
describes a disk larger than the image file, which doesn't end well.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2015-03-09 11:11:59 +01:00