* remotes/bonzini/scsi-next:
megasas: remove buildtime strings
block: iscsi build fix if LIBISCSI_FEATURE_IOVECTOR is not defined
virtio-scsi: Plug memory leak on virtio_scsi_push_event() error path
scsi: Document intentional fall through in scsi_req_length()
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging
Block patches
# gpg: Signature made Mon 19 May 2014 15:21:14 BST using RSA key ID C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
* remotes/kevin/tags/for-upstream: (22 commits)
block: optimize zero writes with bdrv_write_zeroes
blockdev: add a function to parse enum ids from strings
util: add qemu_iovec_is_zero
qcow1: Stricter backing file length check
qcow1: Validate image size (CVE-2014-0223)
qcow1: Validate L2 table size (CVE-2014-0222)
qcow1: Check maximum cluster size
qcow1: Make padding in the header explicit
curl: Add usage documentation
curl: Add sslverify option
curl: Remove broken parsing of options from url
curl: Fix build when curl_multi_socket_action isn't available
qemu-iotests: Fix blkdebug in VM drive in 030
qemu-iotests: Fix core dump suppression in test 039
iotests: Add test for the JSON protocol
block: Allow JSON filenames
check-qdict: Add test for qdict_join()
qdict: Add qdict_join()
block: add test for vhdx image created by Disk2VHD
block: vhdx - account for identical header sections
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Commit b03c380 introduced the function
iscsi_allocationmap_is_allocated(), however it is only used within a
code block that is conditionally compiled. This produces a warning
(error with -werror) of "defined but not used" for the the function, if
LIBISCSI_FEATURE_IOVECTOR is not defined.
This wraps iscsi_allocationmap_is_allocated() in the same conditional.
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
this patch tries to optimize zero write requests
by automatically using bdrv_write_zeroes if it is
supported by the format.
This significantly speeds up file system initialization and
should speed zero write test used to test backend storage
performance.
I ran the following 2 tests on my internal SSD with a
50G QCOW2 container and on an attached iSCSI storage.
a) mkfs.ext4 -E lazy_itable_init=0,lazy_journal_init=0 /dev/vdX
QCOW2 [off] [on] [unmap]
-----
runtime: 14secs 1.1secs 1.1secs
filesize: 937M 18M 18M
iSCSI [off] [on] [unmap]
----
runtime: 9.3s 0.9s 0.9s
b) dd if=/dev/zero of=/dev/vdX bs=1M oflag=direct
QCOW2 [off] [on] [unmap]
-----
runtime: 246secs 18secs 18secs
filesize: 51G 192K 192K
throughput: 203M/s 2.3G/s 2.3G/s
iSCSI* [off] [on] [unmap]
----
runtime: 8mins 45secs 33secs
throughput: 106M/s 1.2G/s 1.6G/s
allocated: 100% 100% 0%
* The storage was connected via an 1Gbit interface.
It seems to internally handle writing zeroes
via WRITESAME16 very fast.
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* remotes/bonzini/scsi-next:
[PATCH] block/iscsi: bump year in copyright notice
block/iscsi: allow cluster_size of 4K and greater
block/iscsi: clarify the meaning of ISCSI_CHECKALLOC_THRES
block/iscsi: speed up read for unallocated sectors
block/iscsi: allow fall back to WRITE SAME without UNMAP
MAINTAINERS: mark megasas as maintained
megasas: Add MSI support
megasas: Enable MSI-X support
megasas: Implement LD_LIST_QUERY
scsi: Improve error messages more
scsi-disk: Improve error messager if can't get version number
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Like qcow2 since commit 6d33e8e7, error out on invalid lengths instead
of silently truncating them to 1023.
Also don't rely on bdrv_pread() catching integer overflows that make len
negative, but use unsigned variables in the first place.
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
A huge image size could cause s->l1_size to overflow. Make sure that
images never require a L1 table larger than what fits in s->l1_size.
This cannot only cause unbounded allocations, but also the allocation of
a too small L1 table, resulting in out-of-bounds array accesses (both
reads and writes).
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Too large L2 table sizes cause unbounded allocations. Images actually
created by qemu-img only have 512 byte or 4k L2 tables.
To keep things consistent with cluster sizes, allow ranges between 512
bytes and 64k (in fact, down to 1 entry = 8 bytes is technically
working, but L2 table sizes smaller than a cluster don't make a lot of
sense).
This also means that the number of bytes on the virtual disk that are
described by the same L2 table is limited to at most 8k * 64k or 2^29,
preventively avoiding any integer overflows.
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Huge values for header.cluster_bits cause unbounded allocations (e.g.
for s->cluster_cache) and crash qemu this way. Less huge values may
survive those allocations, but can cause integer overflows later on.
The only cluster sizes that qemu can create are 4k (for standalone
images) and 512 (for images with backing files), so we can limit it
to 64k.
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
We were relying on all compilers inserting the same padding in the
header struct that is used for the on-disk format. Let's not do that.
Mark the struct as packed and insert an explicit padding field for
compatibility.
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
This allows qemu to use images over https with a self-signed certificate. It
defaults to verifying the certificate.
Signed-off-by: Matthew Booth <mbooth@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The block layer now supports a generic json syntax for passing option parameters
explicitly, making parsing of options from the url redundant.
Signed-off-by: Matthew Booth <mbooth@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The VHDX spec v1.00 declares that "a header is current if it is the only
valid header or if it is valid and its SequenceNumber field is greater
than the other header’s SequenceNumber field. The parser must only use
data from the current header. If there is no current header, then the
VHDX file is corrupt."
However, the Disk2VHD tool from Microsoft creates a VHDX image file that
has 2 identical headers, including matching checksums and matching
sequence numbers. Likely, as a shortcut the tool is just writing the
header twice, for the active and inactive headers, during the image
creation. Technically, this should be considered a corrupt VHDX file
(at least per the 1.00 spec, and that is how we currently treat it).
But in order to accomodate images created with Disk2VHD, we can safely
create an exception for this case. If we find identical sequence
numbers, then we check the VHDXHeader-sized chunks of each 64KB header
sections (we won't rely just on the crc32c to indicate the headers are
the same). If they are identical, then we go ahead and use the first
one.
Reported-by: Nerijus Baliūnas <nerijus@users.sourceforge.net>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The current version of raw-posix always uses ioctl(FS_IOC_FIEMAP) if
FIEMAP is available; lseek with SEEK_HOLE/SEEK_DATA are not even
compiled in in this case. However, there may be implementations which
support the latter but not the former (e.g., NFSv4.2) as well as vice
versa.
To cover both cases, try FIEMAP first (as this will return -ENOTSUP if
not supported instead of returning a failsafe value (everything
allocated as a single extent)) and if that does not work, fall back to
SEEK_HOLE/SEEK_DATA.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The docs for glfs_init suggest that the function sets errno on every
failure. In fact it doesn't. As other functions such as
qemu_gluster_open() in the gluster block code report their errors based
on this fact we need to make sure that errno is set on each failure.
This fixes a crash of qemu-img/qemu when a gluster brick isn't
accessible from given host while the server serving the volume
description is.
Thread 1 (Thread 0x7ffff7fba740 (LWP 203880)):
#0 0x00007ffff77673f8 in glfs_lseek () from /usr/lib64/libgfapi.so.0
#1 0x0000555555574a68 in qemu_gluster_getlength ()
#2 0x0000555555565742 in refresh_total_sectors ()
#3 0x000055555556914f in bdrv_open_common ()
#4 0x000055555556e8e8 in bdrv_open ()
#5 0x000055555556f02f in bdrv_open_image ()
#6 0x000055555556e5f6 in bdrv_open ()
#7 0x00005555555c5775 in bdrv_new_open ()
#8 0x00005555555c5b91 in img_info ()
#9 0x00007ffff62c9c05 in __libc_start_main () from /lib64/libc.so.6
#10 0x00005555555648ad in _start ()
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This will return cluster_size and needs_compressed_writes to caller, if all the
extents have the same value (or there's only one extent). Otherwise return
-ENOTSUP.
cluster_size is only reported for sparse formats.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Add a wrapper function to support "compressed" path in qemu-img convert.
Only support streamOptimized subformat case for now (num_extents == 1
and extent compression is true).
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
After the URL has been parsed make sure the server part is valid in
order to avoid a segmentation fault when calling nfs_mount().
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
If the very first allocation has a length of 0, the free_cluster_index
is still 0 after the for loop, which means that subtracting one from it
will underflow and signal an invalid range of clusters by returning
-EFBIG. However, there is no such range, as its length is 0.
Fix this by preventing underflows on free_cluster_index during the
check.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
When receiving a new aio read request, we first look for an existing
transaction whose range will cover the read request by the time it
completes. However, we weren't checking that the existing transaction
was still active. If it had timed out, we were adding the request to a
transaction which would never complete and had already been cancelled,
resulting in a hang.
Signed-off-by: Matthew Booth <mbooth@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
According to the documentation, the correct way to ensure all
informationals have been returned by curl_multi_info_read is to loop
until it returns NULL.
Signed-off-by: Matthew Booth <mbooth@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
curl_multi_socket_all is a deprecated catch-all which checks for
activities on all open curl sockets. We have enough information from
the event loop to check only the sockets with activity. This change
removes use of curl_multi_socket_all in favour of
curl_multi_socket_action called with the relevant handle.
At the same time, it also ensures that the driver only checks for
completion of read operations after reading from a socket, rather than
both reading and writing.
Signed-off-by: Matthew Booth <mbooth@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Remove calls to curl_multi_do where the relevant handles are already
registered to the event loop.
Ensure that we kick off socket handling with CURL_SOCKET_TIMEOUT after
adding a new handle.
Signed-off-by: Matthew Booth <mbooth@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The driver will not start more than a fixed number of curl sessions.
If it needs more, it must wait for the completion of an existing one.
The driver was sleeping, which will prevent the main loop from
running, and therefore the event it's waiting on. It was also directly
calling its internal handler rather than waiting on existing
registered handlers to be called from the main loop.
This change causes it simply to wait for a period of time whilst
allowing the main loop to execute.
Signed-off-by: Matthew Booth <mbooth@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
A curl write callback is supposed to return the number of bytes it
handled. curl_read_cb would have erroneously reported it had handled
all bytes in the event that the internal curl state was invalid.
Signed-off-by: Matthew Booth <mbooth@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This isn't any of the usually acceptable uses of goto.
Signed-off-by: Matthew Booth <mbooth@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Currently, if an error occurs during the part of vdi_create() which
actually writes the image, the function stores -errno, but continues
anyway.
Instead of trying to write data which (if it can be written at all) does
not make any sense without the operations before succeeding (e.g.,
writing the image header), just error out immediately.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Currently, seek_to_sector() returns -1 both for errors and unallocated
sectors, resulting in silent errors. As 0 is an invalid offset of data
clusters (bitmap_offset is greater than 0 because s->data_offset is
greater than 0), just return 0 for unallocated sectors and -errno in
case of error. This should then be propagated by bochs_read(), the sole
user of seek_to_sector().
That function also has a case of "return -1 in case of error", which is
fixed by this patch as well.
bochs_read() is called by bochs_co_read() which passes the return value
through, therefore it is indeed correct for bochs_read() to return
-errno.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
First, new_l1_size is an int64_t, whereas min_size is a uint64_t.
Therefore, during the loop which adjusts new_l1_size until it equals or
exceeds min_size, new_l1_size might overflow and become negative. The
comparison in the loop condition however will take it as an unsigned
value (because min_size is unsigned) and therefore recognize it as
exceeding min_size. Therefore, the loop is left with a negative
new_l1_size, which is not correct. This could be fixed by making
new_l1_size uint64_t.
On the other hand, however, by doing this, the while loop may take
forever. If min_size is e.g. UINT64_MAX, it will take new_l1_size
probably multiple overflows to reach the exact same value (if it reaches
it at all). Then, right after the loop, new_l1_size will be recognized
as being too big anyway.
Both problems require a ridiculously high min_size value, which is very
unlikely to occur; but both problems are also simply avoided by checking
whether min_size is sane before calculating new_l1_size (which should
still be checked separately, though).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The call to bdrv_getlength() from qcow2_check_refcounts() may result in
an error. Check this and abort if necessary.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Instead of blindly relying on a normal integer having a width of 32 bits
(which is a pretty good assumption, but we should not rely on it if
there is no need), use the correct format string macros.
This does not touch DEBUG output.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
alloc_clusters_noref() stores the cluster index in a uint64_t. However,
offsets are often represented as int64_t (as for example the return
value of alloc_clusters_noref() itself demonstrates). Therefore, we
should make sure all offsets in the allocated range of clusters are
representable using int64_t without overflows.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Currently, bdrv_image_info_specific_dump() uses an error variable for
visit_type_ImageInfoSpecific, but ignores the result. As this function
is used here with an output visitor to transform the ImageInfoSpecific
object to a generic QDict, an error should actually be impossible. It is
however better to assert that this is indeed the case. This is done by
this patch using error_abort instead of an unused local Error variable.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reported-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Instead of having unlink() calls in the generic block layer, where we
aren't even guarateed to have a file name, move them to those block
drivers that are actually used and that always have a filename. Gets us
rid of some #ifdefs as well.
The patch also converts bs->is_temporary to a new BDRV_O_TEMPORARY open
flag so that it is inherited in the protocol layer and the raw-posix and
raw-win32 drivers can unlink the file.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
discard_single_l2() should not implement its own version of
qcow2_get_cluster_type(), but rather rely on this already existing
function. By doing so, it will work for compressed clusters as well
(which it did not so far).
Also, rename "old_offset" to "old_l2_entry", as both are quite different
(and the value is indeed of the latter kind).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
bdrv_get_info could fail. Add check before using the returned value.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The direct return will skip releasing of all the resouces at
immediate_exit, don't miss that.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
depending on the target the opt_unmap_gran might be as low
as 4K. As we know use this also as a knob to activate the allocationmap
feature lower the barrier. The limit 4K (and not 512) is choosen
to avoid a potentially too big allocationmap.
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
this patch implements a cache that tracks if a page on the
iscsi target is allocated or not. The cache is implemented in
a way that it allows for false positives
(e.g. pretending a page is allocated, but it isn't), but
no false negatives.
The cached allocation info is then used to speed up the
read process for unallocated sectors by issueing a GET_LBA_STATUS
request for all sectors that are not yet known to be allocated.
If the read request is confirmed to fall into an unallocated
range we directly return zeroes and do not transfer the
data over the wire.
Tests have shown that a relatively small amount of GET_LBA_STATUS
requests happens a vServer boot time to fill the allocation cache
(all those blocks are not queried again).
Not to transfer all the data of unallocated sectors saves a lot
of time, bandwidth and storage I/O load during block jobs or storage
migration and it saves a lot of bandwidth as well for any big sequential
read of the whole disk (e.g. block copy or speed tests) if a significant
number of blocks is unallocated.
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Although bdrv_getlength() was just called above this, and checked for
error, it is better to just use the value we already get, and use
DIV_ROUND_UP.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
if the iscsi driver receives a write zeroes request with
the BDRV_REQ_MAY_UNMAP flag set it fails with -ENOTSUP
if the iscsi target does not support WRITE SAME with
UNMAP. However, the BDRV_REQ_MAY_UNMAP is only a hint
and writing zeroes with WRITE SAME will still be
better than falling back to writing zeroes with WRITE16.
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* remotes/qmp-unstable/queue/qmp:
monitor: fix qmp_getfd() fd leak in error case
HMP: support specifying dump format for dump-guest-memory
HMP: fix doc of dump-guest-memory
qmp: object-add: Validate class before creating object
monitor: Add device_add and device_del completion.
monitor: Add command_completion callback to mon_cmd_t.
monitor: Fix drive_del id argument type completion.
error: Remove some unused headers
qerror.h: Replace QERR_NOT_SUPPORTED with QERR_UNSUPPORTED
qerror.h: Remove QERR defines that are only used once
qerror.h: Remove unused error classes
error: Print error_report() to stderr if using qmp
monitor: Remove unused monitor_print_filename
error: Privatize error_print_loc
vnc: Remove default_mon usage
slirp: Remove default_mon usage
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Using error_is_set(errp) that way can sweep programming errors under
the carpet when we get called incorrectly with an error set.
Commit 24d3bd6 added a broken error path to iscsi_do_inquiry(): it
first calls error_setg(), then jumps to the preexisting error label,
where error_setg() gets called again, triggering an assertion failure.
Commit cbee81f fixed this by guarding the second error_setg() with an
error_is_set().
Replace this fix by a simpler and safer one: jump right behind the
second error_setg().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Using error_is_set(errp) to check whether a function call failed is
fragile: it breaks when errp is null. Check perfectly suitable return
values instead when possible. errp can't be null there now, but this
is more robust and more obviously correct
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@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. Commit 84d18f0 dumbed
it down to obvious, but a few more have crept in since, and
documentation was overlooked. Dumb these down, too.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
