Commit Graph

306 Commits

Author SHA1 Message Date
Markus Armbruster
39101f2511 QemuOpts: Convert qemu_opt_set_number() to Error, fix its use
Return the Error object instead of reporting it with
qerror_report_err().

Change callers that assume the function can't fail to pass
&error_abort, so that should the assumption ever break, it'll break
noisily.

Turns out all callers outside its unit test assume that.  We could
drop the Error ** argument, but that would make the interface less
regular, so don't.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-02-26 14:47:32 +01:00
Markus Armbruster
cccb7967bd QemuOpts: Convert qemu_opt_set_bool() to Error, fix its use
Return the Error object instead of reporting it with
qerror_report_err().

Change callers that assume the function can't fail to pass
&error_abort, so that should the assumption ever break, it'll break
noisily.

Turns out all callers outside its unit test assume that.  We could
drop the Error ** argument, but that would make the interface less
regular, so don't.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-02-26 14:46:32 +01:00
Paolo Bonzini
439c5e02d5 rcu: add g_free_rcu
This simplifies calling g_free from an RCU callback.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-16 17:30:19 +01:00
Mike Day
341774fe6c rcu: introduce RCU-enabled QLIST
Add RCU-enabled variants on the existing bsd DQ facility. Each
operation has the same interface as the existing (non-RCU)
version. Also, each operation is implemented as macro.

Using the RCU-enabled QLIST, existing QLIST users will be able to
convert to RCU without using a different list interface.

Signed-off-by: Mike Day <ncmike@ncultra.org>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-16 17:30:19 +01:00
Paolo Bonzini
2e91cc62f2 cpu-exec: simplify init_delay_params
With the introduction of QEMU_CLOCK_VIRTUAL_RT, the computation of
sc->diff_clk can be simplified nicely:

        qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
        qemu_clock_get_ns(QEMU_CLOCK_REALTIME) +
        cpu_get_clock_offset()

     =  qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
        (qemu_clock_get_ns(QEMU_CLOCK_REALTIME) - cpu_get_clock_offset())

     =  qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
        (qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timers_state.cpu_clock_offset)

     =  qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
        qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL_RT)

Cc: Sebastian Tanase <sebastian.tanase@openwide.fr>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-02 16:55:11 +01:00
Paolo Bonzini
26387f86c9 rcu: add call_rcu
Asynchronous callbacks provided by call_rcu are particularly important
for QEMU, because the BQL makes it hard to use synchronize_rcu.

In addition, the current RCU implementation is not particularly friendly
to multiple concurrent synchronize_rcu callers, making call_rcu even
more important.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-02 16:55:10 +01:00
Paolo Bonzini
d62cb4f2fd rcu: allow nesting of rcu_read_lock/rcu_read_unlock
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-02 16:55:10 +01:00
Paolo Bonzini
7911747bd4 rcu: add rcu library
This includes a (mangled) copy of the liburcu code.  The main changes
are: 1) removing dependencies on many other header files in liburcu; 2)
removing for simplicity the tentative busy waiting in synchronize_rcu,
which has limited performance effects; 3) replacing futexes in
synchronize_rcu with QemuEvents for Win32 portability.  The API is
the same as liburcu, so it should be possible in the future to require
liburcu on POSIX systems for example and use our copy only on Windows.

Among the various versions available I chose urcu-mb, which is the
least invasive implementation even though it does not have the
fastest rcu_read_{lock,unlock} implementation.  The urcu flavor can
be changed later, after benchmarking.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-02 16:55:10 +01:00
Paolo Bonzini
cd1bd53a66 qemu-timer: introduce timer_deinit
In some cases, a timer was set to NULL so that we could check if it is
initialized.  Use the timer_list field instead, and add a timer_deinit
function that NULLs it.

It then makes sense that timer_del be a no-op (instead of a crasher) on
such a de-initialized timer.  It avoids the need to poke at the timerlist
field to check if the timers are initialized.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-01-26 12:22:44 +01:00
Paolo Bonzini
65a81af8df qemu-timer: add timer_init and timer_init_ns/us/ms
These functions for the main loop TimerListGroup will replace
timer_new and timer_new_ns/us/ms.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-01-26 12:22:44 +01:00
Peter Maydell
db5fd8d709 cpu_ldst.h, cpu-all.h, bswap.h: Update documentation on ld/st accessors
Add documentation of what the cpu_*_* accessors look like.
Correct some minor errors in the existing documentation of the
direct _p accessor family. Remove the near-duplicate comment
on the _p accessors from cpu-all.h and replace it with a reference
to the comment in bswap.h.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1421334118-3287-16-git-send-email-peter.maydell@linaro.org
2015-01-20 15:19:35 +00:00
Paul Durrant
707ff80021 Add device listener interface
The Xen ioreq-server API, introduced in Xen 4.5, requires that PCI device
models explicitly register with Xen for config space accesses. This patch
adds a listener interface into qdev-core which can be used by the Xen
interface code to monitor for arrival and departure of PCI devices.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2015-01-20 14:24:07 +00:00
Dr. David Alan Gilbert
e1a8c9b67f socket shutdown
Add QEMUFile interface to allow a socket to be 'shut down' - i.e. any
reads/writes will fail (and any blocking read/write will be woken).

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2015-01-16 13:06:17 +05:30
Peter Maydell
b629a38a13 Mostly bugfixes and cleanups from qemu-devel. Yet another small patch from
the record/replay series, and a few SCSI and i386 patches as well.
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

Mostly bugfixes and cleanups from qemu-devel.  Yet another small patch from
the record/replay series, and a few SCSI and i386 patches as well.

# gpg: Signature made Wed 14 Jan 2015 09:39:14 GMT using RSA key ID 78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* remotes/bonzini/tags/for-upstream:
  cpus: consistently use QEMU_CLOCK_VIRTUAL_RT for icount_warp_rt timer
  qemu-timer: rename timer_init to timer_init_tl
  scsi: fix cancellation when I/O was completed but DMA was not.
  rules.mak: Fix module build
  hw/scsi/lsi53c895a: add support for additional diag / debug registers
  qemu-common.h: optimise muldiv64 if int128 is available
  target-i386: do not memcpy in and out of xmm_regs
  target-i386: fix movntsd on big-endian hosts
  vl.c: fix regression when reading memory size from config file
  vl: Don't silently change topology when all -smp options were set
  vl: fix max_cpus check
  vl: Avoid unnecessary 'if' nesting
  9pfs: changed to use event_notifier instead of qemu_pipe
  vl.c: fix regression when reading machine type from config file
  char: restore stdio echo on resume from suspend.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-01-14 18:02:47 +00:00
Paolo Bonzini
f186aa976b qemu-timer: rename timer_init to timer_init_tl
timer_init is not called that often.  Free the name for an equivalent
of timer_new.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-01-14 10:38:57 +01:00
Paolo Bonzini
c740ad92d0 QSLIST: add lock-free operations
These operations are trivial to implement and do not have ABA problems.
They are enough to implement simple multiple-producer, single consumer
lock-free lists or, as in the next patch, the multiple consumers can
steal a whole batch of elements and process them at their leisure.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1417518350-6167-5-git-send-email-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-01-13 13:43:29 +00:00
Paolo Bonzini
ef57137f1b qemu-thread: add per-thread atexit functions
Destructors are the main additional feature of pthread TLS compared
to __thread.  If we were using C++ (hint, hint!) we could have used
thread-local objects with a destructor.  Since we are not, instead,
we add a simple Notifier-based API.

Note that the notifier must be per-thread as well.  We can add a
global list as well later, perhaps.

The Win32 implementation has some complications because a) detached
threads used not to have a QemuThreadData; b) the main thread does
not go through win32_start_routine, so we have to use atexit too.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1417518350-6167-3-git-send-email-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-01-13 13:43:29 +00:00
Peter Maydell
a4ba200894 More migration fixes and more record/replay preparations. Also moves
the sdhci-pci device id to make space for the rocker device.
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

More migration fixes and more record/replay preparations.  Also moves
the sdhci-pci device id to make space for the rocker device.

# gpg: Signature made Sat 03 Jan 2015 08:22:36 GMT using RSA key ID 78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* remotes/bonzini/tags/for-upstream:
  pci: move REDHAT_SDHCI device ID to make room for Rocker
  block/iscsi: fix uninitialized variable
  pckbd: set bits 2-3-6-7 of the output port by default
  serial: refine serial_thr_ipending_needed
  gen-icount: check cflags instead of use_icount global
  translate: check cflags instead of use_icount global
  cpu-exec: add a new CF_USE_ICOUNT cflag
  target-ppc: pass DisasContext to SPR generator functions
  atomic: fix position of volatile qualifier

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-01-09 16:29:36 +00:00
Paolo Bonzini
2cbcfb281a atomic: fix position of volatile qualifier
What needs to be volatile is not the pointer, but the pointed-to
value!

Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-23 10:14:46 +01:00
Laszlo Ersek
5712db6ae5 fw_cfg: hard separation between the MMIO and I/O port mappings
We are going to introduce a wide data register for fw_cfg, but only for
the MMIO mapped device. The wide data register will also require the
tightening of endiannesses.

However we don't want to touch the I/O port mapped fw_cfg device at all.

Currently QEMU provides a single fw_cfg device type that can handle both
I/O port and MMIO mapping. This flexibility is not actually exploited by
any board in the tree, but it renders restricting the above changes to
MMIO very hard.

Therefore, let's derive two classes from TYPE_FW_CFG: TYPE_FW_CFG_IO and
TYPE_FW_CFG_MEM.

TYPE_FW_CFG_IO incorporates the base I/O port and the related combined
MemoryRegion. (NB: all boards in the tree that use the I/O port mapped
flavor opt for the combined mapping; that is, when the data port overlays
the high address byte of the selector port. Therefore we can drop the
capability to map those I/O ports separately.)

TYPE_FW_CFG_MEM incorporates the base addresses for the MMIO selector and
data registers, and their respective MemoryRegions.

The "realize" and "props" class members are specific to each new derived
class, and become unused for the base class. The base class retains the
"reset" member and the "vmsd" member, because the reset functionality and
the set of migrated data are not specific to the mapping.

The new functions fw_cfg_init_io() and fw_cfg_init_mem() expose the
possible mappings in separation. For now fw_cfg_init() is retained as a
compatibility shim that enforces the above assumptions.

Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1419250305-31062-2-git-send-email-pbonzini@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-12-22 23:13:10 +00:00
Antony Pavlov
339aaf5b7f qemu-log: add log category for MMU info
Running barebox on qemu-system-mips* with '-d unimp' overloads
stderr by very very many mips_cpu_handle_mmu_fault() messages:

  mips_cpu_handle_mmu_fault address=b80003fd ret 0 physical 00000000180003fd prot 3
  mips_cpu_handle_mmu_fault address=a0800884 ret 0 physical 0000000000800884 prot 3
  mips_cpu_handle_mmu_fault pc a080cd80 ad b80003fd rw 0 mmu_idx 0

So it's very difficult to find LOG_UNIMP message.

The mips_cpu_handle_mmu_fault() messages appear on enabling ANY
logging! It's not very handy.

Adding separate log category for *_cpu_handle_mmu_fault()
logging fixes the problem.

Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Acked-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 1418489298-1184-1-git-send-email-antonynpavlov@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-12-16 18:43:19 +00:00
Peter Maydell
dfa9c2a0f4 - Migration and linuxboot fixes for 2.2 regressions
- valgrind/KVM support
 - small i386 patches
 - PCI SD host controller support
 - malloc/free cleanups from Markus (x86/scsi)
 - IvyBridge model
 - XSAVES support for KVM
 - initial patches from record/replay
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

- Migration and linuxboot fixes for 2.2 regressions
- valgrind/KVM support
- small i386 patches
- PCI SD host controller support
- malloc/free cleanups from Markus (x86/scsi)
- IvyBridge model
- XSAVES support for KVM
- initial patches from record/replay

# gpg: Signature made Mon 15 Dec 2014 16:35:08 GMT using RSA key ID 78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* remotes/bonzini/tags/for-upstream: (47 commits)
  sdhci: Support SDHCI devices on PCI
  sdhci: Define SDHCI PCI ids
  sdhci: Add "sysbus" to sdhci QOM types and methods
  sdhci: Remove class "virtual" methods
  sdhci: Set a default frequency clock
  serial: only resample THR interrupt on rising edge of IER.THRI
  serial: update LSR on enabling/disabling FIFOs
  serial: clean up THRE/TEMT handling
  serial: reset thri_pending on IER writes with THRI=0
  linuxboot: fix loading old kernels
  kvm/apic: fix 2.2->2.1 migration
  target-i386: add Ivy Bridge CPU model
  target-i386: add f16c and rdrand to Haswell and Broadwell
  target-i386: add VME to all CPUs
  pc: add 2.3 machine types
  i386: do not cross the pages boundaries in replay mode
  cpus: make icount warp behave well with respect to stop/cont
  timer: introduce new QEMU_CLOCK_VIRTUAL_RT clock
  cpu-exec: invalidate nocache translation if they are interrupted
  icount: introduce cpu_get_icount_raw
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-12-15 16:43:42 +00:00
Pavel Dovgalyuk
bf2a7ddb0a cpus: make icount warp behave well with respect to stop/cont
This patch makes icount warp use the new QEMU_CLOCK_VIRTUAL_RT clock.
This way, icount's QEMU_CLOCK_VIRTUAL will never count time during which
the virtual machine is stopped.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-15 12:21:02 +01:00
Pavel Dovgalyuk
4e7fa73ec2 timer: introduce new QEMU_CLOCK_VIRTUAL_RT clock
This patch introduces new QEMU_CLOCK_VIRTUAL_RT clock, which
should be used for icount warping.  In the next patch, it
will be used to avoid a huge icount warp when a virtual
machine is stopped for a long time.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-15 12:21:02 +01:00
Pavel Dovgalyuk
2a62914bd8 icount: introduce cpu_get_icount_raw
Separate accessing the instruction counter from the compensation for
speed and halting that are introduced by qemu_icount_bias.  This
introduces new infrastructure used by the record/replay patches.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-15 12:21:02 +01:00
Paolo Bonzini
82595da8de linux-aio: simplify removal of completed iocbs from the list
There is no need to do another O(n) pass on the list; the iocb to
split the list at is already available through the array we passed to
io_submit.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1418305950-30924-6-git-send-email-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-12-12 16:57:55 +00:00
Fam Zheng
43c5d8f800 block: Don't add trailing space in "Formating..." message
Change the message printing code to output a separator for each option
string before it instead of after, then we don't one more extra ' ' in
the end.

To update qemu-iotests output files, most of the times one would just
copy the *.out.bad to *.out. With this change we will not have the
space disliked by checkpatch.pl.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1418110684-19528-3-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-12-12 16:52:33 +00:00
Dr. David Alan Gilbert
64baadc272 Sort include/qemu/typedefs.h
Mainly to make it less likely to conflict during merges.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-12-11 21:00:30 +03:00
Igor Mammedov
a2b257d621 memory: expose alignment used for allocating RAM as MemoryRegion API
introduce memory_region_get_alignment() that returns
underlying memory block alignment or 0 if it's not
relevant/implemented for backend.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-11-23 12:11:30 +02:00
Peter Maydell
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Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

# gpg: Signature made Mon 03 Nov 2014 11:50:53 GMT using RSA key ID 81AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"

* remotes/stefanha/tags/block-pull-request: (53 commits)
  block: declare blockjobs and dataplane friends!
  block: let commit blockjob run in BDS AioContext
  block: let mirror blockjob run in BDS AioContext
  block: let stream blockjob run in BDS AioContext
  block: let backup blockjob run in BDS AioContext
  block: add bdrv_drain()
  blockjob: add block_job_defer_to_main_loop()
  blockdev: add note that block_job_cb() must be thread-safe
  blockdev: acquire AioContext in blockdev_mark_auto_del()
  blockdev: acquire AioContext in do_qmp_query_block_jobs_one()
  block: acquire AioContext in generic blockjob QMP commands
  iotests: Expand test 061
  block/qcow2: Simplify shared L2 handling in amend
  block/qcow2: Make get_refcount() global
  block/qcow2: Implement status CB for amend
  qemu-img: Fix insignificant memleak
  qemu-img: Add progress output for amend
  block: Add status callback to bdrv_amend_options()
  block: qemu-iotest 107 supports NFS
  iotests: Add test for qcow2's bdrv_make_empty
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-11-03 18:34:09 +00:00
Peter Lieven
ac3a872664 util: introduce MIN_NON_ZERO
at least in block layer we have the case of limits being defined for a
BlockDriverState. However, in this context often zero (0) has the special
meanining of undefined which means no limit. If two of those limits are
combined and the minimum is needed the minimum function should only return
zero if both parameters are zero.

Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 09:48:41 +00:00
Eduardo Habkost
d6aaddfe97 bitmap.h: Don't include qemu-common.h
This will avoid unexpected circular header dependencies in the future.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-11-02 10:04:34 +03:00
Eduardo Habkost
afeeead1bc bitops.h: Don't include qemu-common.h
This removes the following circular dependency:

bitops.h -> qemu-common.h -> target-i386/cpu.h -> target-i386/cpu-qom.h ->
qom/cpu.h -> qdev-core.h -> bitmap.h -> bitops.h.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-11-02 10:04:34 +03:00
Markus Armbruster
26f54e9a3c block: New BlockBackend
A block device consists of a frontend device model and a backend.

A block backend has a tree of block drivers doing the actual work.
The tree is managed by the block layer.

We currently use a single abstraction BlockDriverState both for tree
nodes and the backend as a whole.  Drawbacks:

* Its API includes both stuff that makes sense only at the block
  backend level (root of the tree) and stuff that's only for use
  within the block layer.  This makes the API bigger and more complex
  than necessary.  Moreover, it's not obvious which interfaces are
  meant for device models, and which really aren't.

* Since device models keep a reference to their backend, the backend
  object can't just be destroyed.  But for media change, we need to
  replace the tree.  Our solution is to make the BlockDriverState
  generic, with actual driver state in a separate object, pointed to
  by member opaque.  That lets us replace the tree by deinitializing
  and reinitializing its root.  This special need of the root makes
  the data structure awkward everywhere in the tree.

The general plan is to separate the APIs into "block backend", for use
by device models, monitor and whatever other code dealing with block
backends, and "block driver", for use by the block layer and whatever
other code (if any) dealing with trees and tree nodes.

Code dealing with block backends, device models in particular, should
become completely oblivious of BlockDriverState.  This should let us
clean up both APIs, and the tree data structures.

This commit is a first step.  It creates a minimal "block backend"
API: type BlockBackend and functions to create, destroy and find them.

BlockBackend objects are created and destroyed exactly when root
BlockDriverState objects are created and destroyed.  "Root" in the
sense of "in bdrv_states".  They're not yet used for anything; that'll
come shortly.

A root BlockDriverState is created with bdrv_new_root(), so where to
create a BlockBackend is obvious.  Where these roots get destroyed
isn't always as obvious.

It is obvious in qemu-img.c, qemu-io.c and qemu-nbd.c, and in error
paths of blockdev_init(), blk_connect().  That leaves destruction of
objects successfully created by blockdev_init() and blk_connect().

blockdev_init() is used only by drive_new() and qmp_blockdev_add().
Objects created by the latter are currently indestructible (see commit
48f364d "blockdev: Refuse to drive_del something added with
blockdev-add" and commit 2d246f0 "blockdev: Introduce
DriveInfo.enable_auto_del").  Objects created by the former get
destroyed by drive_del().

Objects created by blk_connect() get destroyed by blk_disconnect().

BlockBackend is reference-counted.  Its reference count never exceeds
one so far, but that's going to change.

In drive_del(), the BB's reference count is surely one now.  The BDS's
reference count is greater than one when something else is holding a
reference, such as a block job.  In this case, the BB is destroyed
right away, but the BDS lives on until all extra references get
dropped.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20 13:41:26 +02:00
Dr. David Alan Gilbert
deb22f9a44 QEMUSizedBuffer based QEMUFile
This is based on Stefan and Joel's patch that creates a QEMUFile that goes
to a memory buffer; from:

http://lists.gnu.org/archive/html/qemu-devel/2013-03/msg05036.html

Using the QEMUFile interface, this patch adds support functions for
operating on in-memory sized buffers that can be written to or read from.

Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: Joel Schopp <jschopp@linux.vnet.ibm.com>

For fixes/tweeks I've done:
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-10-14 09:17:06 +02:00
Peter Maydell
fcb2cd928f Four changes here. Polling for reconnection of character devices,
the QOMification of accelerators, a fix for -kernel support on x86, and one
 for a recently-introduced virtio-scsi optimization.
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

Four changes here.  Polling for reconnection of character devices,
the QOMification of accelerators, a fix for -kernel support on x86, and one
for a recently-introduced virtio-scsi optimization.

# gpg: Signature made Thu 09 Oct 2014 14:36:50 BST using RSA key ID 4E6B09D7
# gpg: Good signature from "Paolo Bonzini <pbonzini@redhat.com>"
# gpg:                 aka "Paolo Bonzini <bonzini@gnu.org>"

* remotes/bonzini/tags/for-upstream: (28 commits)
  qemu-char: Fix reconnect socket error reporting
  qemu-sockets: Add error to non-blocking connect handler
  qemu-error: Add error_vreport()
  virtio-scsi: fix use-after-free of VirtIOSCSIReq
  linuxboot: compute initrd loading address
  kvm: Make KVMState be the TYPE_KVM_ACCEL instance struct
  accel: Create accel object when initializing machine
  accel: Pass MachineState object to accel init functions
  accel: Rename 'init' method to 'init_machine'
  accel: Move accel init/allowed code to separate function
  accel: Remove tcg_available() function
  accel: Move qtest accel registration to qtest.c
  accel: Move Xen registration code to xen-common.c
  accel: Move KVM accel registration to kvm-all.c
  accel: Report unknown accelerator as "not found" instead of "does not exist"
  accel: Make AccelClass.available() optional
  accel: Use QOM classes for accel types
  accel: Move accel name lookup to separate function
  accel: Simplify configure_accelerator() using AccelType *acc variable
  accel: Create AccelType typedef
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-10-09 15:09:05 +01:00
Corey Minyard
5179502918 qemu-sockets: Add error to non-blocking connect handler
An error value here would be quite handy and more consistent
with the rest of the code.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
[Make sure SO_ERROR value is passed to error_setg_errno. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-09 15:36:15 +02:00
Corey Minyard
5748e4c2be qemu-error: Add error_vreport()
Needed to nicely print socket error reports.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-09 15:36:15 +02:00
Eduardo Habkost
f6a1ef6440 accel: Pass MachineState object to accel init functions
Most of the machine options and machine state information is in the
MachineState object, not on the MachineClass. This will allow init
functions to use the MachineState object directly instead of
qemu_get_machine_opts() or the current_machine global.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-09 12:57:10 +02:00
Markus Armbruster
f5bebbbb28 util: Emancipate id_wellformed() from QemuOpts
IDs have long spread beyond QemuOpts: not everything with an ID
necessarily goes through QemuOpts.  Commit 9aebf3b is about such a
case: block layer names are meant to be well-formed IDs, but some of
them don't go through QemuOpts, and thus weren't checked.  The commit
fixed that the straightforward way: rename the internal QemuOpts
helper id_wellformed() to qemu_opts_id_wellformed() and give it
external linkage.

Instead of using it directly in block.c, the commit adds wrapper
bdrv_is_valid_name(), probably to hide the connection to QemuOpts.

Go one logical step further: emancipate IDs from QemuOpts.  Rename the
function back to id_wellformed(), and put it in another file.  While
there, clean up its value to bool.  Peel off the bdrv_is_valid_name()
wrapper.

[Replaced stray return 0 with return false to match bool returns used
elsewhere in id_wellformed().
--Stefan]

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-10-03 10:30:33 +01:00
Peter Maydell
1831e15060 This update brings dataplane to virtio-scsi (NOT
yet 100% thread-safe, though, which makes it really, really
 experimental.  It also brings asynchronous cancellation to
 the SCSI subsystem and implements it in virtio-scsi.  This
 is a pretty important feature.  Almost all the work here
 was done by Fam Zheng.
 
 I also included the virtio refcount fixes from Gonglei,
 because they had a small conflict with virtio-scsi dataplane.
 
 This pull request is using the new subkey 4E6B09D7.
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

This update brings dataplane to virtio-scsi (NOT
yet 100% thread-safe, though, which makes it really, really
experimental.  It also brings asynchronous cancellation to
the SCSI subsystem and implements it in virtio-scsi.  This
is a pretty important feature.  Almost all the work here
was done by Fam Zheng.

I also included the virtio refcount fixes from Gonglei,
because they had a small conflict with virtio-scsi dataplane.

This pull request is using the new subkey 4E6B09D7.

# gpg: Signature made Tue 30 Sep 2014 12:31:02 BST using RSA key ID 4E6B09D7
# gpg: Good signature from "Paolo Bonzini <pbonzini@redhat.com>"
# gpg:                 aka "Paolo Bonzini <bonzini@gnu.org>"

* remotes/bonzini/tags/for-upstream: (39 commits)
  block/iscsi: handle failure on malloc of the allocationmap
  util: introduce bitmap_try_new
  virtio-scsi: Handle TMF request cancellation asynchronously
  scsi: Introduce scsi_req_cancel_async
  scsi: Introduce scsi_req_cancel_complete
  scsi: Drop SCSIReqOps.cancel_io
  scsi: Unify request unref in scsi_req_cancel
  scsi-generic: Handle canceled request in scsi_command_complete
  scsi: Drop scsi_req_abort
  virtio-scsi: Process ".iothread" property
  virtio-scsi: Call bdrv_io_plug/bdrv_io_unplug in cmd request handling
  virtio-scsi: Batched prepare for cmd reqs
  virtio-scsi: Two stages processing of cmd request
  virtio-scsi: Add migration state notifier for dataplane code
  virtio-scsi: Hook up with dataplane
  virtio-scsi-dataplane: Code to run virtio-scsi on iothread
  virtio-scsi: Add VirtIOSCSIVring in VirtIOSCSIReq
  virtio-scsi: Add 'iothread' property to virtio-scsi
  virtio: add a wrapper for virtio-backend initialization
  virtio-9p: fix virtio-9p child refcount in transports
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-30 16:45:35 +01:00
Peter Lieven
be4d57c1ea util: introduce bitmap_try_new
regular bitmap_new simply aborts if the memory allocation fails.
bitmap_try_new returns NULL on failure and allows for proper
error handling.

Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-30 13:30:51 +02:00
Richard Henderson
58099c8066 qemu/compiler: Define QEMU_ARTIFICIAL
The combination of always_inline + artificial allows tiny inline
functions to be written that do not interfere with debugging.
In particular, gdb will not step into an artificial function.

The always_inline attribute was introduced in gcc 4.2,
and the artificial attribute was introduced in gcc 4.3.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-09-29 14:55:28 -04:00
Kevin Wolf
9aebf3b892 block: Validate node-name
The device_name of a BlockDriverState is currently checked because it is
always used as a QemuOpts ID and qemu_opts_create() checks whether such
IDs are wellformed.

node-name is supposed to share the same namespace, but it isn't checked
currently. This patch adds explicit checks both for device_name and
node-name so that the same rules will still apply even if QemuOpts won't
be used any more at some point.

qemu-img used to use names with spaces in them, which isn't allowed any
more. Replace them with underscores.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-25 15:24:32 +02:00
Chrysostomos Nanakos
2f78e491d7 async: aio_context_new(): Handle event_notifier_init failure
On a system with a low limit of open files the initialization
of the event notifier could fail and QEMU exits without printing any
error information to the user.

The problem can be easily reproduced by enforcing a low limit of open
files and start QEMU with enough I/O threads to hit this limit.

The same problem raises, without the creation of I/O threads, while
QEMU initializes the main event loop by enforcing an even lower limit of
open files.

This commit adds an error message on failure:

 # qemu [...] -object iothread,id=iothread0 -object iothread,id=iothread1
 qemu: Failed to initialize event notifier: Too many open files in system

Signed-off-by: Chrysostomos Nanakos <cnanakos@grnet.gr>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22 11:39:48 +01:00
Fam Zheng
f6e0830298 util: Move general qemu_getauxval to util/getauxval.c
So that we won't have an empty getauxval.o which is disliked by ranlib.

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-09 13:13:05 +02:00
Peter Maydell
f2fb1da941 Block patches
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block patches

# gpg: Signature made Fri 15 Aug 2014 14:07:42 BST using RSA key ID C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"

* remotes/kevin/tags/for-upstream: (59 commits)
  block: Catch !bs->drv in bdrv_check()
  iotests: Add test for image header overlap
  qcow2: Catch !*host_offset for data allocation
  qcow2: Return useful error code in refcount_init()
  mirror: Handle failure for potentially large allocations
  vpc: Handle failure for potentially large allocations
  vmdk: Handle failure for potentially large allocations
  vhdx: Handle failure for potentially large allocations
  vdi: Handle failure for potentially large allocations
  rbd: Handle failure for potentially large allocations
  raw-win32: Handle failure for potentially large allocations
  raw-posix: Handle failure for potentially large allocations
  qed: Handle failure for potentially large allocations
  qcow2: Handle failure for potentially large allocations
  qcow1: Handle failure for potentially large allocations
  parallels: Handle failure for potentially large allocations
  nfs: Handle failure for potentially large allocations
  iscsi: Handle failure for potentially large allocations
  dmg: Handle failure for potentially large allocations
  curl: Handle failure for potentially large allocations
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-08-15 14:49:50 +01:00
Kevin Wolf
7d2a35cc92 block: Introduce qemu_try_blockalign()
This function returns NULL instead of aborting when an allocation fails.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-08-15 15:07:15 +02:00
Sebastian Tanase
c2aa5f8199 cpu-exec: Add sleeping algorithm
The goal is to sleep qemu whenever the guest clock
is in advance compared to the host clock (we use
the monotonic clocks). The amount of time to sleep
is calculated in the execution loop in cpu_exec.

At first, we tried to approximate at each for loop the real time elapsed
while searching for a TB (generating or retrieving from cache) and
executing it. We would then approximate the virtual time corresponding
to the number of virtual instructions executed. The difference between
these 2 values would allow us to know if the guest is in advance or delayed.
However, the function used for measuring the real time
(qemu_clock_get_ns(QEMU_CLOCK_REALTIME)) proved to be very expensive.
We had an added overhead of 13% of the total run time.

Therefore, we modified the algorithm and only take into account the
difference between the 2 clocks at the begining of the cpu_exec function.
During the for loop we try to reduce the advance of the guest only by
computing the virtual time elapsed and sleeping if necessary. The overhead
is thus reduced to 3%. Even though this method still has a noticeable
overhead, it no longer is a bottleneck in trying to achieve a better
guest frequency for which the guest clock is faster than the host one.

As for the the alignement of the 2 clocks, with the first algorithm
the guest clock was oscillating between -1 and 1ms compared to the host clock.
Using the second algorithm we notice that the guest is 5ms behind the host, which
is still acceptable for our use case.

The tests where conducted using fio and stress. The host machine in an i5 CPU at
3.10GHz running Debian Jessie (kernel 3.12). The guest machine is an arm versatile-pb
built with buildroot.

Currently, on our test machine, the lowest icount we can achieve that is suitable for
aligning the 2 clocks is 6. However, we observe that the IO tests (using fio) are
slower than the cpu tests (using stress).

Signed-off-by: Sebastian Tanase <sebastian.tanase@openwide.fr>
Tested-by: Camille Bégué <camille.begue@openwide.fr>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06 17:53:07 +02:00
KONRAD Frederic
3f03131390 timer: add cpu_icount_to_ns function.
This adds cpu_icount_to_ns function which is needed for reverse execution.

It returns the time for a specific instruction.

Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06 17:53:07 +02:00