Commit Graph

416 Commits

Author SHA1 Message Date
Eric Sunshine
c794b4e0fd Teach block/vdi about "discarded" (no longer allocated) blocks
An entry in the VDI block map will hold an offset to the actual block if
the block is allocated, or one of two specially-interpreted values if
not allocated. Using VirtualBox terminology, value VDI_IMAGE_BLOCK_FREE
(0xffffffff) represents a never-allocated block (semantically arbitrary
content).  VDI_IMAGE_BLOCK_ZERO (0xfffffffe) represents a "discarded"
block (semantically zero-filled).  block/vdi knows only about
VDI_IMAGE_BLOCK_FREE.  Teach it about VDI_IMAGE_BLOCK_ZERO.

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-28 19:25:49 +02:00
Ronnie Sahlberg
c589b24972 iSCSI block driver
This provides built-in support for iSCSI to QEMU.

This has the advantage that the iSCSI devices need not be made visible to the host, which is useful if you have very many virtual machines and very many iscsi devices.
It also has the benefit that non-root users of QEMU can access iSCSI devices across the network without requiring root privilege on the host.

This driver interfaces with the multiplatform posix library for iscsi initiator/client access to iscsi devices hosted at
    git://github.com/sahlberg/libiscsi.git

The patch adds the driver to interface with the iscsi library.
It also updated the configure script to
* by default, probe is libiscsi is available and if so, build
  qemu against libiscsi.
* --enable-libiscsi
  Force a build against libiscsi. If libiscsi is not available
  the build will fail.
* --disable-libiscsi
  Do not link against libiscsi, even if it is available.

When linked with libiscsi, qemu gains support to access iscsi resources such as disks and cdrom directly, without having to make the devices visible to the host.

You can specify devices using a iscsi url of the form :
iscsi://[<username>[:<password>@]]<host>[:<port]/<target-iqn-name>/<lun>
When using authentication, the password can optionally be set with
LIBISCSI_CHAP_PASSWORD="password" to avoid it showing up in the process list

Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-28 19:25:48 +02:00
Paolo Bonzini
6db39ae2e2 block: change discard to co_discard
Since coroutine operation is now mandatory, convert both bdrv_discard
implementations to coroutines.  For qcow2, this means taking the lock
around the operation.  raw-posix remains synchronous.

The bdrv_discard callback is then unused and can be eliminated.

Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-21 17:34:14 +02:00
Paolo Bonzini
8b94ff8573 block: change flush to co_flush
Since coroutine operation is now mandatory, convert all bdrv_flush
implementations to coroutines.  For qcow2, this means taking the lock.
Other implementations are simpler and just forward bdrv_flush to the
underlying protocol, so they can avoid the lock.

The bdrv_flush callback is then unused and can be eliminated.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-21 17:34:14 +02:00
Paolo Bonzini
e183ef75cc block: take lock around bdrv_write implementations
This does the first part of the conversion to coroutines, by
wrapping bdrv_write implementations to take the mutex.

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

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-21 17:34:14 +02:00
Paolo Bonzini
2914caa088 block: take lock around bdrv_read implementations
This does the first part of the conversion to coroutines, by
wrapping bdrv_read implementations to take the mutex.

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

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

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-21 17:34:14 +02:00
Paolo Bonzini
848c66e8f5 block: add a CoMutex to synchronous read drivers
The big conversion of bdrv_read/write to coroutines caused the two
homonymous callbacks in BlockDriver to become reentrant.  It goes
like this:

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

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

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

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

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

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

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-21 17:34:13 +02:00
Paolo Bonzini
bae0a0cc38 vmdk: clean up open
Move vmdk_parent_open to vmdk_open.  There's another path how
vmdk_parent_open can be reached:

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

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

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

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

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

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

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

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-21 17:34:13 +02:00
Paolo Bonzini
588b65a37a vmdk: fix return values of vmdk_parent_open
While vmdk_open_desc_file (touched by the patch) correctly changed -1
to -EINVAL, vmdk_open did not.  Fix it directly in vmdk_parent_open.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-21 17:34:13 +02:00
Kevin Wolf
8f1efd00c4 qcow2: Fix bdrv_write_compressed error handling
If during allocation of compressed clusters the cluster was already allocated
uncompressed, fail and properly release the l2_table (the latter avoids a
failed assertion).

While at it, make it return some real error numbers instead of -1.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
2011-10-21 17:34:13 +02:00
Paolo Bonzini
4265d620c5 block: add bdrv_co_discard and bdrv_aio_discard support
This similarly adds support for coroutine and asynchronous discard.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-21 17:34:13 +02:00
Stefan Hajnoczi
6f6dc6565e block: drop redundant bdrv_flush implementation
Block drivers now only need to provide either of .bdrv_co_flush,
.bdrv_aio_flush() or for legacy drivers .bdrv_flush().  Remove
the redundant .bdrv_flush() implementations.

[Paolo Bonzini: change raw driver to bdrv_co_flush]

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-21 17:34:13 +02:00
Paolo Bonzini
d8716b41b9 sheepdog: add coroutine_fn markers
This makes the following patch easier to review.

Cc: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-21 17:34:12 +02:00
Anthony Liguori
2a22e6eb1b Merge remote-tracking branch 'kwolf/for-anthony' into staging 2011-10-14 12:36:50 -05:00
Stefan Hajnoczi
d8b7e0adf5 block: use coroutine interface for raw format
The raw format delegates all operations to bs->file (the protocol).
Previously this block driver exposed both sync and aio interfaces.
Since the block layer now works in terms of coroutines, expose the
coroutine interfaces and drop the others.  This avoids unnecessary
emulation of sync and aio interfaces.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-14 17:31:22 +02:00
Stefan Hajnoczi
1b1e8c6ec7 raw-posix: remove bdrv_read()/bdrv_write()
Block drivers only need to provide one of sync, aio, or coroutine
interfaces.  Since raw-posix.c provides aio interfaces, simply drop the
synchronous interfaces since they can be emulated using aio and
coroutines.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-14 17:31:22 +02:00
Stefan Weil
add8d26203 block/qcow: Fix use of free() instead of g_free()
cppcheck reported this error:

qemu/block/qcow.c:599: error: Mismatching allocation and deallocation: cluster_data

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-10-14 14:57:46 +01:00
Dong Xu Wang
7acae208ca sheepdog: correct spelling
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-10-14 14:46:59 +01:00
Kevin Wolf
0d460d6f41 vvfat: Fix potential buffer overflow
path2[PATH_MAX] can be used for the null termination, so make the array big
enough to allow this.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-11 09:42:46 +02:00
Stefan Weil
7ef6d3dc39 block/vvfat: Remove unused code
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>
2011-10-11 09:42:45 +02:00
Stefan Weil
ce137829e7 block/vvfat: Fix potential memory leaks and other memory errors
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>
2011-10-11 09:42:45 +02:00
Christoph Hellwig
55b949c847 block: allow resizing of images residing on host devices
Allow to resize images that reside on host devices up to the available
space.  This allows to grow images after resizing the device manually or
vice versa.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-11 09:41:46 +02:00
Stefan Hajnoczi
e4fc8781db qed: fix use-after-free during l2 cache commit
QED's metadata caching strategy allows two parallel requests to race for
metadata lookup.  The first one to complete will populate the metadata
cache and the second one will drop the data it just read in favor of the
cached data.

There is a use-after-free in qed_read_l2_table_cb() and
qed_commit_l2_update() where l2_table->offset was used after the
l2_table may have been freed due to a metadata lookup race.  Fix this by
keeping the l2_offset in a local variable and not reaching into the
possibly freed l2_table.

Reported-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-10-05 10:52:31 -05:00
Nick Thomas
363c3c8535 block/curl: Don't finish AIOCBs too early
The previous behaviour was to finish AIOCBs inside curl_aio_readv()
if the data was cached. This caused the following failed assertion
at hw/ide/pci.c:314: bmdma_cmd_writeb

"Assertion `bm->bus->dma->aiocb == ((void *)0)' failed."

By scheduling a QEMUBH and performing the completion inside the
callback, we avoid this problem.

Signed-off-by: Nick Thomas <nick@bytemark.co.uk>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-21 15:16:04 +02:00
Nick Thomas
c84dcdc1d6 block/curl: Implement a flush function on the fd handlers
Signed-off-by: Nick Thomas <nick@bytemark.co.uk>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-21 15:16:02 +02:00
Sage Weil
16a06b2430 rbd: allow escaping in config string
The config string is variously delimited by =, @, and /, depending on the
field.  Allow these characters to be escaped by preceeding them with \.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-20 14:34:17 +02:00
Sage Weil
7a3f5fe9af rbd: call flush, if available
librbd recently added async writeback and flush support.  If the new
rbd_flush() call is available, call it.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-20 12:27:44 +02:00
Sage Weil
9e1fbcde57 rbd: update comment heading
Properly document the configuration string syntax and semantics.  Remove
(out of date) details about the librbd implementation.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-20 12:27:44 +02:00
Sage Weil
f9fe18ec77 rbd: ignore failures when reading from default conf location
If we are reading from the default config location, ignore any failures.
It is perfectly legal for the user to specify exactly the options they need
and to not rely on any config file.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-20 12:27:44 +02:00
Fam Zheng
b3c0bfb6f9 VMDK: fix leak of extent_file
Release extent_file on error in vmdk_parse_extents. Added closing files
in freeing extents.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-20 12:27:43 +02:00
Kevin Wolf
074abad326 raw-posix: Fix bdrv_flush error return values
bdrv_flush is supposed to use 0/-errno return values

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-19 11:34:33 +02:00
Paolo Bonzini
b90fb4b8f5 nbd: support feature negotiation
nbd supports writing flags in bytes 24...27 of the header,
and uses that for the read-only flag.  Add support for it
in qemu-nbd.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-19 11:34:33 +02:00
Stefan Weil
b2bedb2144 Remove blanks before \n in output strings
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>
2011-09-16 08:25:56 -05:00
Frediano Ziglio
ee18e73023 qcow2: fix range check
QCowL2Meta::offset is not cluster aligned but only sector aligned
however nb_clusters count cluster from cluster start.
This fix range check. Note that old code have no corruption issues
related to this check cause it only cause intersection to occur
when shouldn't.

Signed-off-by: Frediano Ziglio <freddy77@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12 15:17:22 +02:00
Frediano Ziglio
dea43a65d6 qcow2: align cluster_data to block to improve performance using O_DIRECT
Signed-off-by: Frediano Ziglio <freddy77@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12 15:17:22 +02:00
Frediano Ziglio
05140499d3 qcow2: initialize metadata before inserting in cluster_allocs
QCow2Meta structure was inserted into list before many fields are
initialized. Currently is not a problem cause all occur in a lock
but if qcow2_alloc_clusters would in a future unlock this lock
some issues could arise.
Initializing fields before inserting fix the problem.

Signed-off-by: Frediano Ziglio <freddy77@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12 15:17:22 +02:00
Markus Armbruster
ab359cd17e nbd: Clean up use of block_int.h
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12 15:17:22 +02:00
Sage Weil
eb93d5d990 rbd: fix leak in qemu_rbd_open failure paths
Fix leak of s->snap in failure path.  Simplify error paths for the whole
function.

Reported-by: Stefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: Sage Weil <sage@newdream.net>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12 15:17:21 +02:00
Sage Weil
dfe80b071b rbd: clean up, fix style
No assignment in condition.  Remove duplicate ret > 0 check.

Signed-off-by: Sage Weil <sage@newdream.net>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12 15:17:21 +02:00
Sage Weil
7c7e9df023 rbd: allow client id to be specified in config string
Allow the client id to be specified in the config string via 'id=' so that
users can control who they authenticate as.  Currently they are stuck with
the default ('admin').  This is necessary for anyone using authentication
in their environment.

Signed-off-by: Sage Weil <sage@newdream.net>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12 15:17:20 +02:00
Markus Armbruster
025e849a50 block: Rename bdrv_set_locked() to bdrv_lock_medium()
While there, make the locked parameter bool.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12 15:17:20 +02:00
Frediano Ziglio
a791236992 qcow2: removed unused depends_on field
Signed-off-by: Frediano Ziglio <freddy77@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-12 15:17:17 +02:00
Fam Zheng
bb45ded931 VMDK: bugfix, opening vSphere 4 exported image
The vSphere 4 exported image is streamOptimized extent, which is not
quite correctly handled. Ignore rdgOffset when RGD flag bit not set.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-06 12:33:29 +02:00
Fam Zheng
f16f509d17 VMDK: bugfix, open Haiku vmdk image
Haiku provides a specially formed vmdk image, which let qemu abort. It a
combination of sparse header and flat data (i.e. with not l1/l2 table at
all). The fix is turn to descriptor when sparse header is zero in field
'capacity'.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-06 12:33:03 +02:00
Fam Zheng
6c031aac4d VMDK: creating streamOptimized subformat
Creating streamOptimized subformat. Added subformat option
'streamOptimized', to create a image with compression enabled and each
cluster with a GrainMarker.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-06 12:31:33 +02:00
Fam Zheng
2b2c8c5dec VMDK: read/write compressed extent
Add support for reading/writing compressed extent.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-06 12:30:28 +02:00
Fam Zheng
432bb170af VMDK: Opening compressed extent.
Added flags field for compressed/streamOptimized extents, open and save
image configuration.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-06 12:27:42 +02:00
Fam Zheng
dd3f6ee211 VMDK: separate vmdk_read_extent/vmdk_write_extent
Factor out read/write extent code, since there will be more things to
take care of once reading/writing compressed clusters is introduced.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-06 12:25:32 +02:00
Fam Zheng
86c6b429bf VMDK: add twoGbMaxExtentSparse support
Add twoGbMaxExtentSparse support. Introduce vmdk_free_last_extent.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-06 12:22:02 +02:00
Fam Zheng
6398de5160 VMDK: enable twoGbMaxExtentFlat
Enable the createType 'twoGbMaxExtentFlat'. The supporting code is
already in.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-06 12:20:43 +02:00