Yet another optimization is to extend the mirroring iteration to include more
adjacent dirty blocks. This limits the number of I/O operations and makes
mirroring efficient even with a small granularity. Most of the infrastructure
is already in place; we only need to put a loop around the computation of
the origin and sector count of the iteration.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
With AIO support in place, we can start copying more than one chunk
in parallel. This patch introduces the required infrastructure for
this: the buffer is split into multiple granularity-sized chunks,
and there is a free list to access them.
Because of copy-on-write, a single operation may already require
multiple chunks to be available on the free list.
In addition, two different iterations on the HBitmap may want to
copy the same cluster. We avoid this by keeping a bitmap of in-flight
I/O operations, and blocking until the previous iteration completes.
This should be a pretty rare occurrence, though; as long as there is
no overlap the next iteration can start before the previous one finishes.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
There is really no change in the behavior of the job here, since
there is still a maximum of one in-flight I/O operation between
the source and the target. However, this patch already introduces
the AIO callbacks (which are unmodified in the next patch)
and some of the logic to count in-flight operations and only
complete the job when there is none.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
When mirroring runs, the backing files for the target may not yet be
ready. However, this means that a copy-on-write operation on the target
would fill the missing sectors with zeros. Copy-on-write only happens
if the granularity of the dirty bitmap is smaller than the cluster size
(and only for clusters that are allocated in the source after the job
has started copying). So far, the granularity was fixed to 1MB; to avoid
the problem we detected the situation and required the backing files to
be available in that case only.
However, we want to lower the granularity for efficiency, so we need
a better solution. The solution is to always copy a whole cluster the
first time it is touched. The code keeps a bitmap of clusters that
have already been allocated by the mirroring job, and only does "manual"
copy-on-write if the chunk being copied is zero in the bitmap.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This actually uses the dirty bitmap in the block layer, and converts
mirroring to use an HBitmapIter.
Reviewed-by: Laszlo Ersek <lersek@redhat.com> (except block/mirror.c parts)
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
HBitmaps provides an array of bits. The bits are stored as usual in an
array of unsigned longs, but HBitmap is also optimized to provide fast
iteration over set bits; going from one bit to the next is O(logB n)
worst case, with B = sizeof(long) * CHAR_BIT: the result is low enough
that the number of levels is in fact fixed.
In order to do this, it stacks multiple bitmaps with progressively coarser
granularity; in all levels except the last, bit N is set iff the N-th
unsigned long is nonzero in the immediately next level. When iteration
completes on the last level it can examine the 2nd-last level to quickly
skip entire words, and even do so recursively to skip blocks of 64 words or
powers thereof (32 on 32-bit machines).
Given an index in the bitmap, it can be split in group of bits like
this (for the 64-bit case):
bits 0-57 => word in the last bitmap | bits 58-63 => bit in the word
bits 0-51 => word in the 2nd-last bitmap | bits 52-57 => bit in the word
bits 0-45 => word in the 3rd-last bitmap | bits 46-51 => bit in the word
So it is easy to move up simply by shifting the index right by
log2(BITS_PER_LONG) bits. To move down, you shift the index left
similarly, and add the word index within the group. Iteration uses
ffs (find first set bit) to find the next word to examine; this
operation can be done in constant time in most current architectures.
Setting or clearing a range of m bits on all levels, the work to perform
is O(m + m/W + m/W^2 + ...), which is O(m) like on a regular bitmap.
When iterating on a bitmap, each bit (on any level) is only visited
once. Hence, The total cost of visiting a bitmap with m bits in it is
the number of bits that are set in all bitmaps. Unless the bitmap is
extremely sparse, this is also O(m + m/W + m/W^2 + ...), so the amortized
cost of advancing from one bit to the next is usually constant.
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Many callers pass size_t, which gets silently truncated to uint32_t.
Harmless, because all practical sizes are well below 4GiB. Clean it
up anyway. Size overflow now fails assertions.
Bonus: saves a whole bunch of silly casts.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
virtio-blk-data-plane is a subset implementation of virtio-blk. It only
handles read, write, and flush requests. It does this using a dedicated
thread that executes an epoll(2)-based event loop and processes I/O
using Linux AIO.
This approach performs very well but can be used for raw image files
only. The number of IOPS achieved has been reported to be several times
higher than the existing virtio-blk implementation.
Eventually it should be possible to unify virtio-blk-data-plane with the
main body of QEMU code once the block layer and hardware emulation is
able to run outside the global mutex.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The virtio-blk-data-plane cannot access memory using the usual QEMU
functions since it executes outside the global mutex and the memory APIs
are this time are not thread-safe.
This patch introduces a virtqueue module based on the kernel's vhost
vring code. The trick is that we map guest memory ahead of time and
access it cheaply outside the global mutex.
Once the hardware emulation code can execute outside the global mutex it
will be possible to drop this code.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Add a new spice chardev to allow arbitrary communication between the
host and the Spice client via the spice server.
Examples:
This allows the Spice client to have a special port for the qemu
monitor:
... -chardev spiceport,name=org.qemu.monitor,id=monitorport
-mon chardev=monitorport
v2:
- remove support for chardev to chardev linking
- conditionnaly compile with SPICE_SERVER_VERSION
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This patch adds tracing / debugging calls to the XICS interrupt controller
implementation used on the pseries machine.
Signed-off-by: Ben Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
Now that we have separate status and length fields in USBPacket
update the completion tracepoint to log both.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Starting with commit 1c380f9460 dma
transfers can actually fail. This patch makes ehci keep track
of the busmaster bit in pci config space, by setting/clearing the
dma_context pointer. Attempts to dma without context will result
in raising HSE (Host System Error) interrupt and stopping the host
controller.
This patch fixes WinXP not booting with a usb stick attached to ehci.
Root cause is seabios activating ehci so you can boot from the stick,
and WinXP clearing the busmaster bit before resetting the host
controller, leading to ehci actually trying dma while it is disabled.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
* kraxel/usb.69: (31 commits)
usb-redir: Allow redirecting super speed devices to high speed controllers
usb-redir: Allow to attach USB 2.0 devices to 1.1 host controller
usb-redir: Use reject rather the disconnect on bad ep info
usb-redir: Add an usbredir_setup_usb_eps() helper function
usb-redir: Add support for input pipelining
usb-redir: Add support for 32 bits bulk packet length
combined-packet: Add a workaround for Linux usbfs + live migration
usb: Add packet combining functions
uhci: Don't crash on device disconnect
uhci: Add a uhci_handle_td_error() helper function
usb/ehci-pci: add helper to create ich9 usb controllers
usb/ehci-pci: add ich9 00:1a.* variant
usb/ehci-pci: dynamic type generation
uhci: add ich9 00:1a.* variants
uhci: stick irq routing info into UHCIInfo too.
uhci: dynamic type generation
xilinx_zynq: add USB controllers
usb/ehci: add sysbus variant
usb/ehci: split into multiple source files
usb/ehci: Guard definition of EHCI_DEBUG
...
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Add a generic thread-pool. The code is roughly based on posix-aio-compat.c,
with some changes, especially the following:
- use QemuSemaphore instead of QemuCond;
- separate the state of the thread from the return code of the worker
function. The return code is totally opaque for the thread pool;
- do not busy wait when doing cancellation.
A more generic threadpool (but still specific to I/O so that in the future
it can use special scheduling classes or PI mutexes) can have many uses:
it allows more flexibility in raw-posix.c and can more easily be extended
to Win32, and it will also be used to do an msync of the persistent bitmap.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* kraxel/usb.68: (36 commits)
xhci: fix usb name in caps
xhci: make number of interrupters and slots configurable
xhci: allow disabling interrupters
xhci: flush endpoint context unconditinally
xhci: fix function name in error message
uhci: Use only one queue for ctrl endpoints
uhci: Retry to fill the queue while waiting for td completion
uhci: Always mark a queue valid when we encounter it
uhci: When the guest marks a pending td non-active, cancel the queue
uhci: Detect guest td re-use
uhci: Verify queue has not been changed by guest
uhci: Immediately free queues on device disconnect
uhci: Store ep in UHCIQueue
uhci: Make uhci_fill_queue() actually operate on an UHCIQueue
uhci: Add uhci_read_td() helper function
uhci: Rename UHCIAsync->td to UHCIAsync->td_addr
uhci: Move emptying of the queue's asyncs' queue to uhci_queue_free
uhci: Drop unnecessary forward declaration of some static functions
uhci: Don't retry on error
uhci: cleanup: Add an unlink call to uhci_async_cancel()
...
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
According to the spec a guest can unlink a qh, and then as soon as frindex
has changed by 1 since the unlink, assume it is idle and re-use it. However
for various reasons, we cannot simply consider a qh as unlinked if we've not
seen it for 1 frame. This means that it is possible for a guest to re-use /
restart the queue while we still see its old state. This patch adds a safety
check for this, and "early" retires queues when they were changed by the guest.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This patch adds the implementation of a new job that mirrors a disk to
a new image while letting the guest continue using the old image.
The target is treated as a "black box" and data is copied from the
source to the target in the background. This can be used for several
purposes, including storage migration, continuous replication, and
observation of the guest I/O in an external program. It is also a
first step in replacing the inefficient block migration code that is
part of QEMU.
The job is possibly never-ending, but it is logically structured into
two phases: 1) copy all data as fast as possible until the target
first gets in sync with the source; 2) keep target in sync and
ensure that reopening to the target gets a correct (full) copy
of the source data.
The second phase is indicated by the progress in "info block-jobs"
reporting the current offset to be equal to the length of the file.
When the job is cancelled in the second phase, QEMU will run the
job until the source is clean and quiescent, then it will report
successful completion of the job.
In other words, the BLOCK_JOB_CANCELLED event means that the target
may _not_ be consistent with a past state of the source; the
BLOCK_JOB_COMPLETED event means that the target is consistent with
a past state of the source. (Note that it could already happen
that management lost the race against QEMU and got a completion
event instead of cancellation).
It is not yet possible to complete the job and switch over to the target
disk. The next patches will fix this and add many refinements to the
basic idea introduced here. These include improved error management,
some tunable knobs and performance optimizations.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
While streaming can be dropped as soon as it progressed through the whole
image, mirroring needs to be completed manually for two reasons: 1) so that
management knows exactly when the VM switches to the target; 2) because
for other use cases such as replication, we may leave the operation running
for the whole life of the virtual machine.
Add a new block job command that manually completes background operations.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Add QMP commands matching the functionality.
Paused jobs cannot be canceled without first resuming them. This
ensures that I/O errors are never missed by management. However, an
optional force argument can be specified to allow that.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This adds the live commit coroutine. This iteration focuses on the
commit only below the active layer, and not the active layer itself.
The behaviour is similar to block streaming; the sectors are walked
through, and anything that exists above 'base' is committed back down
into base. At the end, intermediate images are deleted, and the
chain stitched together. Images are restored to their original open
flags upon completion.
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* 'usb.65' of git://git.kraxel.org/qemu:
uhci: Don't queue up packets after one with the SPD flag set
usb-redir: Revert usb-redir part of commit 93bfef4c
usb-redir: Add chardev open / close debug logging
usb-redir: Add support for migration
usb-redir: Store max_packet_size in endp_data
usb-redir: Add an already_in_flight packet-id queue
usb-redir: Change cancelled packet code into a generic packet-id queue
ehci: Walk async schedule before and after migration
ehci: Don't set seen to 0 when removing unseen queue-heads
configure: usbredir fixes
ehci: Don't process too much frames in 1 timer tick (v2)
ehci: Fix interrupts stopping when Interrupt Threshold Control is 8
ehci: switch to new-style memory ops
usb-host: allow emulated (non-async) control requests without USBPacket
Until now we used only the agent to change the monitor count and each
monitor resolution. This patch introduces the qemu part of using the
device as the mediator instead of the agent via virtio-serial.
Spice (>=0.11.5) calls the new QXLInterface::client_monitors_config,
which returns wether the interrupt is enabled, and if so and given a non
NULL monitors config will
generate an interrupt QXL_INTERRUPT_CLIENT_MONITORS_CONFIG with crc
checksum for the guest to verify a second call hasn't interfered.
The maximal number of monitors is limited on the QXLRom to 64.
Signed-off-by: Alon Levy <alevy@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Add two new trace events:
qxl_send_events(int qid, uint32_t events) "%d %d"
qxl_set_guest_bug(int qid) "%d"
Change qxl_io_unexpected_vga_mode parameters to be equivalent to those
of qxl_io_write for easier grouping under a single systemtap probe.
Change d to qxl in one place.
Signed-off-by: Alon Levy <alevy@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Also register different memory regions for capabilities,
operational registers and port status registers. Create
separate tracepoints for operational regs and port status
regs. Ditch a bunch of sanity checks because the memory
core will do this for us now.
Offloading the byte, word and dword access handling to the
memory core also has the side effect of fixing ehci register
access on bigendian hosts.
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Move all state belonging to the (single) interrupter into a separate
struct. First step in adding support for multiple interrupters.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This patch splits the xhci_xfer_data function into three.
The xhci_xfer_data function used to do does two things:
(1) copy transfer data between guest memory and a temporary buffer.
(2) report transfer results to the guest using events.
Now we three functions to handle this:
(1) xhci_xfer_map creates a scatter list for the transfer and
uses that (instead of the temporary buffer) to build a
USBPacket.
(2) xhci_xfer_unmap undoes the mapping.
(3) xhci_xfer_report sends out events.
The patch also fixes reporting of transaction errors which must be
reported unconditinally, not only in case the guest asks for it
using the ISP flag.
[ v2: fix warning ]
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
make qemu_queue_{cancel,reset} return the number of packets released,
so the caller can figure whenever there have been active packets even
though there shouldn't have been any. Add tracepoint to log this.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Revision bumped to 4 for new IO support, enabled for spice-server >=
0.11.1. New io enabled if revision is 4. Revision can be set to 4.
[ kraxel: 3 continues to be the default revision. Once we have a new
stable spice-server release and the qemu patches to enable
the new bits merged we'll go flip the switch and make rev4
the default ]
This io calls the corresponding new spice api
spice_qxl_monitors_config_async to let spice-server read a new guest set
monitors config and notify the client.
On migration reissue spice_qxl_monitors_config_async.
RHBZ: 770842
Signed-off-by: Alon Levy <alevy@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
fixup
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This provides floppy and IDE controllers as well as serial and parallel
ports. However, dynamic configuration of devices is not yet supported.
Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
[AF: QOM'ify, split out header, create CharDriverState if absent]
Signed-off-by: Andreas Färber <andreas.faerber@web.de>
This patch implements MSI and MSI-X support for the pseries PCI host
bridge. To do this it adds:
* A "config_space_address to msi_table" map, since the MSI RTAS calls
take a PCI config space address as an identifier.
* A MSIX memory region to catch msi_notify()/msix_notiry() from
virtio-pci and pass them to the guest via qemu_irq_pulse().
* RTAS call "ibm,change-msi" which sets up MSI vectors for a
device. Note that this call may configure and return lesser number of
vectors than requested.
* RTAS call "ibm,query-interrupt-source-number" which translates MSI
vector to interrupt controller (XICS) IRQ number.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
[agraf: fix error case ndev < 0]
Signed-off-by: Alexander Graf <agraf@suse.de>
This adds a trace event in the pseries PCI specific set_irq() function to
assist in debugging.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
[agraf: add trace.h include]
Signed-off-by: Alexander Graf <agraf@suse.de>
When a device is resized, we will report a unit attention condition
for CAPACITY DATA HAS CHANGED. However, we should ensure that this
condition does not override a more important unit attention condition.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
trace_megasas_dcmd_dump_frame() takes 9 arguments, which is
rather much. Plus the trace infrastructure doesn't support
it. As we can get the information via other means it's pointless
to have it in the driver, so rather use some proper trace
point here and remove the old one.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Cc: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
