Commit Graph

19 Commits

Author SHA1 Message Date
Manos Pitsidianakis
9a1f02a354 hw/xen/xen-hvm-common.c: convert DPRINTF to tracepoints
Tracing DPRINTFs to stderr might not be desired. A developer that relies
on tracepoints should be able to opt-in to each tracepoint and rely on
QEMU's log redirection, instead of stderr by default.

This commit converts DPRINTFs in this file that are used for tracing
into tracepoints.

Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: b000ab73022dfeb7a7ab0ee8fd0f41fb208adaf0.1706544115.git.manos.pitsidianakis@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2024-02-02 13:51:59 +00:00
Manos Pitsidianakis
0402b96830 hw/xen/xen-mapcache.c: convert DPRINTF to tracepoints
Tracing DPRINTFs to stderr might not be desired. A developer that relies
on tracepoints should be able to opt-in to each tracepoint and rely on
QEMU's log redirection, instead of stderr by default.

This commit converts DPRINTFs in this file that are used for tracing
into tracepoints.

Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 2fbe1fbc59078e384761c932e97cfa4276a53d75.1706544115.git.manos.pitsidianakis@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2024-02-02 13:51:59 +00:00
Stefano Stabellini
f17068c1c7 xen-hvm: reorganize xen-hvm and move common function to xen-hvm-common
This patch does following:
1. creates arch_handle_ioreq() and arch_xen_set_memory(). This is done in
    preparation for moving most of xen-hvm code to an arch-neutral location,
    move the x86-specific portion of xen_set_memory to arch_xen_set_memory.
    Also, move handle_vmport_ioreq to arch_handle_ioreq.

2. Pure code movement: move common functions to hw/xen/xen-hvm-common.c
    Extract common functionalities from hw/i386/xen/xen-hvm.c and move them to
    hw/xen/xen-hvm-common.c. These common functions are useful for creating
    an IOREQ server.

    xen_hvm_init_pc() contains the architecture independent code for creating
    and mapping a IOREQ server, connecting memory and IO listeners, initializing
    a xen bus and registering backends. Moved this common xen code to a new
    function xen_register_ioreq() which can be used by both x86 and ARM machines.

    Following functions are moved to hw/xen/xen-hvm-common.c:
        xen_vcpu_eport(), xen_vcpu_ioreq(), xen_ram_alloc(), xen_set_memory(),
        xen_region_add(), xen_region_del(), xen_io_add(), xen_io_del(),
        xen_device_realize(), xen_device_unrealize(),
        cpu_get_ioreq_from_shared_memory(), cpu_get_ioreq(), do_inp(),
        do_outp(), rw_phys_req_item(), read_phys_req_item(),
        write_phys_req_item(), cpu_ioreq_pio(), cpu_ioreq_move(),
        cpu_ioreq_config(), handle_ioreq(), handle_buffered_iopage(),
        handle_buffered_io(), cpu_handle_ioreq(), xen_main_loop_prepare(),
        xen_hvm_change_state_handler(), xen_exit_notifier(),
        xen_map_ioreq_server(), destroy_hvm_domain() and
        xen_shutdown_fatal_error()

3. Removed static type from below functions:
    1. xen_region_add()
    2. xen_region_del()
    3. xen_io_add()
    4. xen_io_del()
    5. xen_device_realize()
    6. xen_device_unrealize()
    7. xen_hvm_change_state_handler()
    8. cpu_ioreq_pio()
    9. xen_exit_notifier()

4. Replace TARGET_PAGE_SIZE with XC_PAGE_SIZE to match the page side with Xen.

Signed-off-by: Vikram Garhwal <vikram.garhwal@amd.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@amd.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
2023-06-15 16:45:59 -07:00
Vikram Garhwal
e7218dd57c hw/i386/xen/: move xen-mapcache.c to hw/xen/
xen-mapcache.c contains common functions which can be used for enabling Xen on
aarch64 with IOREQ handling. Moving it out from hw/i386/xen to hw/xen to make it
accessible for both aarch64 and x86.

Signed-off-by: Vikram Garhwal <vikram.garhwal@amd.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@amd.com>
Reviewed-by: Paul Durrant <paul@xen.org>
2023-06-15 16:45:58 -07:00
David Woodhouse
e2abfe5ec6 hw/xen: Rename xen_common.h to xen_native.h
This header is now only for native Xen code, not PV backends that may be
used in Xen emulation. Since the toolstack libraries may depend on the
specific version of Xen headers that they pull in (and will set the
__XEN_TOOLS__ macro to enable internal definitions that they depend on),
the rule is that xen_native.h (and thus the toolstack library headers)
must be included *before* any of the headers in include/hw/xen/interface.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
2023-03-07 17:04:30 +00:00
Stefano Garzarella
d0fb9657a3 docs: fix references to docs/devel/tracing.rst
Commit e50caf4a5c ("tracing: convert documentation to rST")
converted docs/devel/tracing.txt to docs/devel/tracing.rst.

We still have several references to the old file, so let's fix them
with the following command:

  sed -i s/tracing.txt/tracing.rst/ $(git grep -l docs/devel/tracing.txt)

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210517151702.109066-2-sgarzare@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-06-02 06:51:09 +02:00
Paul Durrant
3809f7583b xen: perform XenDevice clean-up in XenBus watch handler
Cleaning up offline XenDevice objects directly in
xen_device_backend_changed() is dangerous as xen_device_unrealize() will
modify the watch list that is being walked. Even the QLIST_FOREACH_SAFE()
used in notifier_list_notify() is insufficient as *two* notifiers (for
the frontend and backend watches) are removed, thus potentially rendering
the 'next' pointer unsafe.

The solution is to use the XenBus backend_watch handler to do the clean-up
instead, as it is invoked whilst walking a separate watch list.

This patch therefore adds a new 'inactive_devices' list to XenBus, to which
offline devices are added by xen_device_backend_changed(). The XenBus
backend_watch registration is also changed to not only invoke
xen_bus_enumerate() but also a new xen_bus_cleanup() function, which will
walk 'inactive_devices' and perform the necessary actions.
For safety an extra 'online' check is also added to xen_bus_type_enumerate()
to make sure that no attempt is made to create a new XenDevice object for a
backend that is offline.

NOTE: This patch also includes some cosmetic changes:
      - substitute the local variable name 'backend_state'
        in xen_bus_type_enumerate() with 'state', since there
        is no ambiguity with any other state in that context.
      - change xen_device_state_is_active() to
        xen_device_frontend_is_active() (and pass a XenDevice directly)
        since the state tests contained therein only apply to a frontend.
      - use 'state' rather then 'xendev->backend_state' in
        xen_device_backend_changed() to shorten the code.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Message-Id: <20190913082159.31338-4-paul.durrant@citrix.com>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-09-24 12:18:47 +01:00
Paul Durrant
d198b711f9 xen: introduce separate XenWatchList for XenDevice objects
This patch uses the XenWatchList abstraction to add a separate watch list
for each device. This is more scalable than walking a single notifier
list for all watches and is also necessary to implement a bug-fix in a
subsequent patch.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Anthony Perard <anthony.perard@citrix.com>
Message-Id: <20190913082159.31338-3-paul.durrant@citrix.com>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-09-24 12:18:47 +01:00
Paul Durrant
374752a26b xen / notify: introduce a new XenWatchList abstraction
Xenstore watch call-backs are already abstracted away from XenBus using
the XenWatch data structure but the associated NotifierList manipulation
and file handle registration is still open coded in various xen_bus_...()
functions.
This patch creates a new XenWatchList data structure to allow these
interactions to be abstracted away from XenBus as well. This is in
preparation for a subsequent patch which will introduce separate watch lists
for XenBus and XenDevice objects.

NOTE: This patch also introduces a new notifier_list_empty() helper function
      for the purposes of adding an assertion that a XenWatchList is not
      freed whilst its associated NotifierList is still occupied.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Anthony Perard <anthony.perard@citrix.com>
Message-Id: <20190913082159.31338-2-paul.durrant@citrix.com>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-09-24 12:18:47 +01:00
Markus Armbruster
500016e5db trace-events: Shorten file names in comments
We spell out sub/dir/ in sub/dir/trace-events' comments pointing to
source files.  That's because when trace-events got split up, the
comments were moved verbatim.

Delete the sub/dir/ part from these comments.  Gets rid of several
misspellings.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190314180929.27722-3-armbru@redhat.com
Message-Id: <20190314180929.27722-3-armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-03-22 16:18:07 +00:00
Paul Durrant
a783f8ad4e xen: add a mechanism to automatically create XenDevice-s...
...that maintains compatibility with existing Xen toolstacks.

Xen toolstacks instantiate PV backends by simply writing information into
xenstore and expecting a backend implementation to be watching for this.

This patch adds a new 'xen-backend' module to allow individual XenDevice
implementations to register create and destroy functions. The creator
will be called when a tool-stack instantiates a new backend in this way,
and the destructor will then be called after the resulting XenDevice
object is unrealized.

To support this it is also necessary to add new watchers into the XenBus
implementation to handle enumeration of new backends and also destruction
of XenDevice-s when the toolstack sets the backend 'online' key to 0.

NOTE: This patch only adds the framework. A subsequent patch will add a
      creator function for xen-block devices.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Anthony Perard <anthony.perard@citrix.com>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-01-14 13:45:40 +00:00
Paul Durrant
b6af8926fb xen: add implementations of xen-block connect and disconnect functions...
...and wire in the dataplane.

This patch adds the remaining code to make the xen-block XenDevice
functional. The parameters that a block frontend expects to find are
populated in the backend xenstore area, and the 'ring-ref' and
'event-channel' values specified in the frontend xenstore area are
mapped/bound and used to set up the dataplane.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Anthony Perard <anthony.perard@citrix.com>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-01-14 13:45:40 +00:00
Paul Durrant
82a29e3048 xen: add xenstore watcher infrastructure
A Xen PV frontend communicates its state to the PV backend by writing to
the 'state' key in the frontend area in xenstore. It is therefore
necessary for a XenDevice implementation to be notified whenever the
value of this key changes.

This patch adds code to do this as follows:

- an 'fd handler' is registered on the libxenstore handle which will be
  triggered whenever a 'watch' event occurs
- primitives are added to xen-bus-helper to add or remove watch events
- a list of Notifier objects is added to XenBus to provide a mechanism
  to call the appropriate 'watch handler' when its associated event
  occurs

The xen-block implementation is extended with a 'frontend_changed' method,
which calls as-yet stub 'connect' and 'disconnect' functions when the
relevant frontend state transitions occur. A subsequent patch will supply
a full implementation for these functions.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Anthony Perard <anthony.perard@citrix.com>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-01-14 13:45:40 +00:00
Paul Durrant
094a22399f xen: create xenstore areas for XenDevice-s
This patch adds a new source module, xen-bus-helper.c, which builds on
basic libxenstore primitives to provide functions to create (setting
permissions appropriately) and destroy xenstore areas, and functions to
'printf' and 'scanf' nodes therein. The main xen-bus code then uses
these primitives [1] to initialize and destroy the frontend and backend
areas for a XenDevice during realize and unrealize respectively.

The 'xen-block' implementation is extended with a 'get_name' method that
returns the VBD number. This number is required to 'name' the xenstore
areas.

NOTE: An exit handler is also added to make sure the xenstore areas are
      cleaned up if QEMU terminates without devices being unrealized.

[1] The 'scanf' functions are actually not yet needed, but they will be
    needed by code delivered in subsequent patches.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Anthony Perard <anthony.perard@citrix.com>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-01-14 13:45:40 +00:00
Paul Durrant
108f7bba15 xen: introduce new 'XenBus' and 'XenDevice' object hierarchy
This patch adds the basic boilerplate for a 'XenBus' object that will act
as a parent to 'XenDevice' PV backends.
A new 'XenBridge' object is also added to connect XenBus to the system bus.

The XenBus object is instantiated by a new xen_bus_init() function called
from the same sites as the legacy xen_be_init() function.

Subsequent patches will flesh-out the functionality of these objects.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Anthony Perard <anthony.perard@citrix.com>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
2019-01-14 13:45:40 +00:00
Vladimir Sementsov-Ogievskiy
db73ee4bc8 trace-events: fix code style: %# -> 0x%
In trace format '#' flag of printf is forbidden. Fix it to '0x%'.

This patch is created by the following:

check that we have a problem
> find . -name trace-events | xargs grep '%#' | wc -l
56

check that there are no cases with additional printf flags before '#'
> find . -name trace-events | xargs grep "%[-+ 0'I]+#" | wc -l
0

check that there are no wrong usage of '#' and '0x' together
> find . -name trace-events | xargs grep '0x%#' | wc -l
0

fix the problem
> find . -name trace-events | xargs sed -i 's/%#/0x%/g'

[Eric Blake noted that xargs grep '%[-+ 0'I]+#' should be xargs grep
"%[-+ 0'I]+#" instead so the shell quoting is correct.
--Stefan]

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20170731160135.12101-3-vsementsov@virtuozzo.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-08-01 12:13:07 +01:00
Philippe Mathieu-Daudé
87e0331c5a docs: fix broken paths to docs/devel/tracing.txt
With the move of some docs/ to docs/devel/ on ac06724a71,
no references were updated.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2017-07-31 13:12:53 +03:00
Paul Durrant
1c599472b0 xen: use libxendevice model to restrict operations
This patch adds a command-line option (-xen-domid-restrict) which will
use the new libxendevicemodel API to restrict devicemodel [1] operations
to the specified domid. (Such operations are not applicable to the xenpv
machine type).

This patch also adds a tracepoint to allow successful enabling of the
restriction to be monitored.

[1] I.e. operations issued by libxendevicemodel. Operation issued by other
    xen libraries (e.g. libxenforeignmemory) are currently still unrestricted
    but this will be rectified by subsequent patches.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2017-04-21 12:40:14 -07:00
Daniel P. Berrange
1416f9ea6d trace: move hw/xen events to correct subdir
The trace-events for a given source file should generally
always live in the same directory as the source file.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170125161417.31949-4-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-01-31 17:11:17 +00:00