Allow bdrv_open() to handle references to existing block devices just as
bdrv_file_open() is already capable of.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Make bdrv_open() take a pointer to a BDS pointer, similarly to
bdrv_file_open(). If a pointer to a NULL pointer is given, bdrv_open()
will create a new BDS with an empty name; if the BDS pointer is not
NULL, that existing BDS will be reused (in the same way as bdrv_open()
already did).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
error_is_set(&var) is the same as var != NULL, but it takes
whole-program analysis to figure that out. Unnecessarily hard for
optimizers, static checkers, and human readers. Dumb it down to
obvious.
Gets rid of several dozen Coverity false positives.
Note that the obvious form is already used in many places.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
This is a boiler-plate _nofail variant of qemu_opts_create. Remove and
use error_abort in call sites.
null/0 arguments needs to be added for the id and fail_if_exists fields
in affected callsites due to argument inconsistency between the normal and
no_fail variants.
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
The buildbot shows these compiler warnings:
block/vvfat.c: In function 'create_short_and_long_name':
block/vvfat.c:620: warning: array size (8) smaller than bound length (11)
block/vvfat.c:620: warning: array size (8) smaller than bound length (11)
block/vvfat.c:635: warning: array size (8) smaller than bound length (11)
block/vvfat.c:635: warning: array size (8) smaller than bound length (11)
They are caused by tricky code where 8 characters for the name are followed
by 3 characters for the extension, and some operations touch both name and
extension.
Using an 11 character name which includes the extension fixes the compiler
warning, satisfies cppcheck, valgrind and maybe other static and dynamic
code checkers, and even simplifies some parts of the code.
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Add an Error ** parameter to bdrv_create and its associated functions to
allow more specific error messages.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Add an Error ** parameter to bdrv_open, bdrv_file_open and associated
functions to allow more specific error messages.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Add an Error ** parameter to BlockDriver.bdrv_open and
BlockDriver.bdrv_file_open to allow more specific error messages.
Signed-off-by: Max Reitz <mreitz@redhat.com>
For now, bdrv_get_block_status is just another name for bdrv_is_allocated.
The next patches will add more flags.
This also touches all block drivers with a mostly mechanical rename. The
sole exception is cow; because it calls cow_co_is_allocated from the read
code, we keep that function and make cow_co_get_block_status a wrapper.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Manage BlockDriverState lifecycle with refcnt, so bdrv_delete() is no
longer public and should be called by bdrv_unref() if refcnt is
decreased to 0.
This is an identical change because effectively, there's no multiple
reference of BDS now: no caller of bdrv_ref() yet, only bdrv_new() sets
bs->refcnt to 1, so all bdrv_unref() now actually delete the BDS.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
we need bdrv_new() to properly initialize BDS, don't allocate memory
manually.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
s->qcow and s->qcow_filename are allocated but not freed on error. Fix the
possible leaks, remove unnecessary check for bdrv_new(), propagate ret code of
bdrv_create() and also the one of enable_write_target().
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
It doesn't do anything yet except storing the options QDict in the
BlockDriverState.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This allows removing of MinGW specific code and improves
reentrancy for POSIX hosts.
[Removed unused ret variable in qemu_get_timedate() to fix warning:
vl.c: In function ‘qemu_get_timedate’:
vl.c:451:16: error: variable ‘ret’ set but not used [-Werror=unused-but-set-variable]
-- Stefan Hajnoczi]
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This patch converts all block layer close calls, that correspond
to qemu_open calls, to qemu_close.
Signed-off-by: Corey Bryant <coreyb@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch converts all block layer open calls to qemu_open.
Note that this adds the O_CLOEXEC flag to the changed open paths
when the O_CLOEXEC macro is defined.
Signed-off-by: Corey Bryant <coreyb@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
vvfat creates a virtual VFAT filesystem with a certain logical
geometry that depends on its options. It sets the "geometry hint" to
this geometry. It is the only block driver to do this.
The geometry hint is about about *physical* geometry, and used only by
certain hard disk device models.
vvfat's hint is normally invisible for device models, because
bdrv_open() puts a raw format on top of vvfat's fat protocol. That
raw format is where drive_init() puts the user's geometry (if any),
and where the device model gets it from.
Nobody complained, because the default physical geometry is the same
as vvfat's logical geometry:
opts LCHS def. PCHS
1024,16,63 same
:32: 1024,16,63 same
:16: 1024,16,63 same
:12: 64,16,63 same
Except when you specify :floppy:
opts LCHS def. PCHS
:floppy: 80, 2,36 5,16,63
:32:floppy: 80, 2,36 5,16,63
:16:floppy: 80, 2,36 5,16,63
:12:floppy: 80, 2,18 2,16,63
Silly thing to do for use with a hard disk.
However, the "raw" format can be suppressed by adding an
redundant-looking "format=vvfat" to "file=fat:FOO". Then, vvfat's
hint clobbers the user's geometry, i.e. -drive options cyls, heads,
secs get silently ignored. Don't do that.
No change without format=vvfat. With it, the user's hard disk
geometry (-drive options cyls, heads, secs) is now obeyed, and the
default hard disk geometry with :floppy: now matches the one without
format=vvfat.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Unless parameter ":floppy:" is given, vvfat creates a virtual image
with DOS MBR defining a single partition which holds the FAT file
system. The size of the virtual image depends on the width of the
FAT: 32 MiB (CHS 64, 16, 63) for 12 bit FAT, 504 MiB (CHS 1024, 16,
63) for 16 and 32 bit FAT, leaving (64*16-1)*63 = 64449 and
(1024*16-1)*64 = 1032129 sectors for the partition.
However, it screws up the end of the partition in the MBR:
FAT width param. start CHS end CHS start LBA size
:32: 0,1,1 1023,14,63 63 1032065
:16: 0,1,1 1023,14,55 63 1032057
:12: 0,1,1 63,14,55 63 64377
The actual FAT file system nevertheless assumes the partition has
1032129 or 64449 sectors. Oops.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
In snapshot mode, bdrv_open creates an empty temporary file without
checking for mkstemp or close failure, and ignoring the possibility
of a buffer overrun given a surprisingly long $TMPDIR.
Change the get_tmp_filename function to return int (not void),
so that it can inform its two callers of those failures.
Also avoid the risk of buffer overrun and do not ignore mkstemp
or close failure.
Update both callers (in block.c and vvfat.c) to propagate
temp-file-creation failure to their callers.
get_tmp_filename creates and closes an empty file, while its
callers later open that presumed-existing file with O_CREAT.
The problem was that a malicious user could provoke mkstemp failure
and race to create a symlink with the selected temporary file name,
thus causing the qemu process (usually root owned) to open through
the symlink, overwriting an attacker-chosen file.
This addresses CVE-2012-2652.
http://bugzilla.redhat.com/CVE-2012-2652
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Jim Meyering <meyering@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
QED's opaque data includes a pointer back to the BlockDriverState.
This breaks when bdrv_append shuffles data between bs_new and bs_top.
To avoid this, add a "rebind" function that tells the driver about
the new relationship between the BlockDriverState and its opaque.
The patch also adds rebind to VVFAT for completeness, even though
it is not used with live snapshots.
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
It is trivial to switch from the synchronous .bdrv_is_allocated()
interface to .bdrv_co_is_allocated() since vvfat_is_allocated() does not
block.
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
vvfat caches more or less everything when in writable mode. For migration
to work, it would have to be invalidated. Block migration for now when
in writable mode (default is readonly).
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
vvfat used to directly call into the qcow2 block driver instead of using the
block.c wrappers. With the coroutine conversion, this stopped working.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
First determine FAT12/16/32, then compute geometry from that for both
FDD and HDD. For 1.44MB floppies, and 2.88MB floppies using FAT16,
change to 1 sector/cluster. The default remains 2.88MB with FAT12
and 2 sectors/cluster. Both DOS and mkdosfs by default format a 2.88MB
floppy as FAT12.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The sector count is stored in the partition and hence must not include the
sectors before its start. At the same time, remove the useless special
casing for 1.44 MB floppies. This fixes fsck on VVFAT hard disks,
which otherwise tries to seek past the end of the disk.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This is consistent with what "real" floppies have, so file(1)
now actually recognizes the VVFAT image as a 1.44 MB floppy.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
If the number of "faked sectors" + the number of sectors that are
part of a cluster does not sum up to the total number of sectors,
qemu-img convert fails. Read these spare sectors as all zeros.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
When reading the address of the first free entry, you cannot
use array_get without first marking all entries as occupied.
This is visible if you change the sectors per cluster on a
floppy from 2 to 1.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
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>
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>
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>
The unused code was detected using cppcheck.
Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
cppcheck reported memory leaks and mismatched g_malloc() with free()
instead of g_free().
Fix these errors.
Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Those blanks violate the coding conventions, see
scripts/checkpatch.pl.
Blanks missing after colons in the changed lines were added.
This patch does not try to fix tabs, long lines and other
problems in the changed lines, therefore checkpatch.pl reports
many violations.
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Most changes were made using these commands:
git grep -la '__attribute__((packed))'|xargs perl -pi -e 's/__attribute__\(\(packed\)\)/QEMU_PACKED/'
git grep -la '__attribute__ ((packed))'|xargs perl -pi -e 's/__attribute__ \(\(packed\)\)/QEMU_PACKED/'
git grep -la '__attribute__((__packed__))'|xargs perl -pi -e 's/__attribute__\(\(__packed__\)\)/QEMU_PACKED/'
git grep -la '__attribute__ ((__packed__))'|xargs perl -pi -e 's/__attribute__ \(\(__packed__\)\)/QEMU_PACKED/'
git grep -la '__attribute((packed))'|xargs perl -pi -e 's/__attribute\(\(packed\)\)/QEMU_PACKED/'
Whitespace in linux-user/syscall_defs.h was fixed manually
to avoid warnings from scripts/checkpatch.pl.
Manual changes were also applied to hw/pc.c.
I did not fix indentation with tabs in block/vvfat.c.
The patch will show 4 errors with scripts/checkpatch.pl.
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Fix a file descriptor leak, reported by cppcheck:
[/src/qemu/block/vvfat.c:759]: (error) Resource leak: dir
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Fix this compiler warning:
./block/vvfat.c:2285: error: comparison of unsigned expression >= 0 is always true
Cc: Blue Swirl <blauwirbel@gmail.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
The qcow file used for write support in vvfat is a temporary file,
so we can use cache=unsafe there. Without this, write support is just
too slow to be of any use.
Signed-off-by: Kevin Wolf <mail@kevin-wolf.de>
Allocation and deallocation of bs->opaque is not in the control of a
block driver. Therefore it should not set bs->opaque to a data structure
used by another bs, or closing the image will lead to a double free.
Signed-off-by: Kevin Wolf <mail@kevin-wolf.de>
Max Reitz