In order to close a race window for Xenstore live update when using
the new unique_id of domains, the migration stream needs to contain
this unique_id for each domain known by Xenstore.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
Instead of checking each known domain after having received a
VIRQ_DOM_EXC event, use the new xenmanage_poll_changed_domain()
function for directly getting the domid of a domain having changed
its state.
A test doing "xl shutdown" of 1000 guests has shown to reduce the
consumed cpu time of xenstored by 6% with this change applied.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Use the new unique_id of a domain in order to detect that a domain
has been replaced with another one reusing the domain-id of the old
domain.
While changing the related code, switch from "dom_invalid" to
"dom_valid" in order to avoid double negation and use "bool" as type
for it.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
In docs/misc/xenstore.txt all Xenstore commands are specified, but
the specifications lack the numerical values of the commands.
Add a table with all commands, their values, and a potential remark
(e.g. whether the command is optional).
Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
a653sched_do_schedule() is using two function local static variables,
which is resulting in bad behavior when using more than one cpupool
with the arinc653 scheduler.
Fix that by moving those variables to the scheduler private data.
Fixes: 22787f2e10 ("ARINC 653 scheduler")
Reported-by: Choi Anderson <Anderson.Choi@boeing.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Nathan Studer <nathan.studer@dornerworks.com>
The description of the Xenstore INTRODUCE command is still referencing
xend. Fix that.
The <evtchn> description is starting with a grammatically wrong
sentence. Fix that.
While at it, make clear that the Xenstore implementation is allowed
to ignore the specified gfn and use the Xenstore reserved grant id
GNTTAB_RESERVED_XENSTORE instead.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
xs_get_domain_path() can be simplified by using single_with_domid().
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
VIRQs are split into "global" and "per vcpu" ones. Unfortunately in
reality there are "per domain" ones, too.
send_global_virq() and set_global_virq_handler() make only sense for
the real "global" ones, so replace virq_is_global() with a new
function get_virq_type() returning one of the 3 possible types (global,
domain, vcpu VIRQ).
To make its intended purpose more clear, also rename
send_guest_global_virq() to send_guest_domain_virq().
Fixes: 980822c5ed ("xen/events: allow setting of global virq handler only for unbound virqs")
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Some use cases of get_global_virq_handler() didn't account for the
case of running without hardware domain.
Fix that by testing get_global_virq_handler() returning NULL where
needed (e.g. when directly dereferencing the result).
Fixes: 980822c5ed ("xen/events: allow setting of global virq handler only for unbound virqs")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
The GET_FEATURE, SET_FEATURE, GET_QUOTA and SET_QUOTA Xenstore commands
are defined in docs/misc/xenstore.txt, but they are missing in
xs_wire.h.
Add the missing commands to xs_wire.h
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
xs_wire.h contains some defines XS_WRITE_* which seem to be leftovers
from some decades ago. They haven't been used in the Xen tree since at
least Xen 2.0 and they make no sense anyway.
Remove them, as they seem not to be related to any Xen interface we
have today.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Replace the current use of the unstable xc_domain_getinfo_single()
interface with the stable domctl XEN_DOMCTL_get_domain_state call
via the new libxenmanage library.
This will remove the last usage of libxenctrl by Xenstore, so update
the library dependencies accordingly.
For now only do a direct replacement without using the functionality
of obtaining information about domains having changed the state.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
In order to have a stable interface in user land for using stable
domctl and possibly later sysctl interfaces, add a new library
libxenmanage.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Add a new domctl sub-function to get data of a domain having changed
state (this is needed by Xenstore).
The returned state just contains the domid, the domain unique id,
and some flags (existing, shutdown, dying).
In order to enable Xenstore stubdom being built for multiple Xen
versions, make this domctl stable. For stable domctls the
interface_version is always 0.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Add a bitmap with one bit per possible domid indicating the respective
domain has changed its state (created, deleted, dying, crashed,
shutdown).
Registering the VIRQ_DOM_EXC event will result in setting the bits for
all existing domains and resetting all other bits.
As the usage of this bitmap is tightly coupled with the VIRQ_DOM_EXC
event, it is meant to be used only by a single consumer in the system,
just like the VIRQ_DOM_EXC event.
Resetting a bit will be done in a future patch.
This information is needed for Xenstore to keep track of all domains.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
XEN_DOMCTL_set_virq_handler will happily steal a global virq from the
current domain having bound it and assign it to another domain. The
former domain will just never receive any further events for that
virq without knowing what happened.
Change the behavior to allow XEN_DOMCTL_set_virq_handler only if the
virq in question is not bound by the current domain allowed to use it.
Currently the only user of XEN_DOMCTL_set_virq_handler in the Xen code
base is init-xenstore-domain, so changing the behavior like above will
not cause any problems.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Today Xen will happily allow binding a global virq by a domain which
isn't configured to receive it. This won't result in any bad actions,
but the bind will appear to have succeeded with no event ever being
received by that event channel.
Instead of allowing the bind, error out if the domain isn't set to
handle that virq. Note that this check is inside the write_lock() on
purpose, as a future patch will put a related check into
set_global_virq_handler() with the addition of using the same lock.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Channels work differently than other device types: their devid should
be -1 initially in order to distinguish them from the primary console
which has the devid of 0.
So when parsing the channel configuration, use
ARRAY_EXTEND_INIT_NODEVID() in order to avoid overwriting the devid
set by libxl_device_channel_init().
Fixes: 3a66796347 ("libxl: set channel devid when not provided by application")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
There are several places in list.h where "list_struct" is used instead
of "struct list_head". Fix that.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
There is a possible race scenario between set_global_virq_handler()
and clear_global_virq_handlers() targeting the same domain, which
might result in that domain ending as a zombie domain.
In case set_global_virq_handler() is being called for a domain which
is just dying, it might happen that clear_global_virq_handlers() is
running first, resulting in set_global_virq_handler() taking a new
reference for that domain and entering in the global_virq_handlers[]
array afterwards. The reference will never be dropped, thus the domain
will never be freed completely.
This can be fixed by checking the is_dying state of the domain inside
the region guarded by global_virq_handlers_lock. In case the domain is
dying, handle it as if the domain wouldn't exist, which will be the
case in near future anyway.
Fixes: 87521589aa ("xen: allow global VIRQ handlers to be delegated to other domains")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Instead of having to include xenctrl.h for getting definitions of cpu
barriers, add a dedicated header for that purpose.
Switch the xen-9pfsd daemon to use the new header instead of xenctrl.h.
This is in preparation of making Xenstore independent from libxenctrl.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Xenstore is referencing domains by their domid, but reuse of a domid
can lead to the situation that Xenstore can't tell whether a domain
with that domid has been deleted and created again without Xenstore
noticing the domain is a new one now.
Add a global domain creation unique id which is updated when creating
a new domain, and store that value in struct domain of the new domain.
The global unique id is initialized with the system time and updates
are done via the xorshift algorithm which is used for pseudo random
number generation, too (see https://en.wikipedia.org/wiki/Xorshift).
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Alejandro Vallejo <alejandro.vallejo@cloud.com>
Today the dummy XSM privilege checks for getdomaininfo are less
stringent than possible: they basically rely on the general
sysctl/domctl entry check to do all tests and then do the test with
the XSM_HOOK privilege, which is an "allow all" default.
Instead of XSM_HOOK use XSM_XS_PRIV, which is the privilege really
wanted. Note that this test is still wider than the sysctl entry test,
but there is no easy way to make both domctl and sysctl happy at the
same time.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Daniel P. Smith <dpsmith@apertussolutions.com>
domctl.h and sysctl.h have an interface version, which needs to be
bumped in case of incompatible modifications of the interface.
In order to avoid misunderstandings, add a comment to both headers
specifying in which cases a bump is needed.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Today the build of Xenstore stubdoms depend on libxenguest just because
libxenguest depends on all needed libraries. In reality there is no
dependency on libxenguest for Xenstore stubdoms.
Use the actual dependencies instead.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Today the xenstored Makefile contains an unneeded reference to the
not used libxenguest library.
Remove it.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Today Mini-OS can only be configured to use all or no Xen libraries.
In order to prepare a more fine grained configuration scheme, add per
library config items to the Mini-OS config files.
As some libraries pull in others, the config files need to be
extended at build time to reflect those indirect library uses.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
In order to be able to use the xenlibs-dependencies macro from stubdom
build, move it to tools/libs/uselibs.mk, which is included from
current users and stubdom/Makefile.
No functional change intended.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Anthony PERARD <anthony.perard@vates.tech>
Today the Mini-OS build systems derives libc and lwip config options
from the stubdom and LWIPDIR make variables supplied by the Xen build
system.
In order to prepare those being explicit Mini-OS config options, add
them to the related stubdom Mini-OS config files.
While at it remove the CONFIG_START_NETWORK setting from config files
disabling lwip, as CONFIG_START_NETWORK requires lwip for becoming
effective.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
With the introduction of 9pfs for Xenstore-stubdom it is now possible
to use a file for saving the state when doing live update.
This allows to move some environment specific actions back to the
common source file lu.c.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
In case cpu_schedule_up() is failing, it needs to undo all externally
visible changes it has done before.
Reason is that cpu_schedule_callback() won't be called with the
CPU_UP_CANCELED notifier in case cpu_schedule_up() did fail.
Fixes: 207589dbac ("xen/sched: move per cpu scheduler private data into struct sched_resource")
Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
The CPU POOLS sections in MAINTAINERS can be dropped, as the SCHEDULING
section has the same maintainers and it is covering the CPU POOLS files
as well.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
I've been active in the scheduling code since many years now. Add
me as a maintainer.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: George Dunlap <george.dunlap@cloud.com>
With lock handling now allowing up to 16384 cpus (spinlocks can handle
65535 cpus, rwlocks can handle 16384 cpus), raise the allowed limit for
the number of cpus to be configured to 16383.
The new limit is imposed by IOMMU_CMD_BUFFER_MAX_ENTRIES and
QINVAL_MAX_ENTRY_NR required to be larger than 2 * CONFIG_NR_CPUS.
Add a support limit of physical CPUs to SUPPORT.md (4096 on x86, 128
on ARM).
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
In case a test is failing in test-xenstore, let the tool exit with an
exit status other than 0.
Fix a typo in an error message.
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Fixes: 3afc5e4a5b ("tools/tests: add xenstore testing framework")
Signed-off-by: Juergen Gross <jgross@suse.com>
Today test-xenstore will write nodes with 3000 bytes node data. This
size is exceeding the default quota for the allowed node size. While
working in dom0 with C-xenstored, OCAML-xenstored does not like that.
Use a size of 2000 instead, which is lower than the allowed default
node size of 2048.
Fixes: 3afc5e4a5b ("tools/tests: add xenstore testing framework")
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
ASM_INT() is defined in arch/[arm|x86]/include/asm/asm_defns.h in
exactly the same way. Instead of replicating this definition for riscv
and ppc, move it to include/xen/linkage.h, where other arch agnostic
definitions for assembler code are living already.
Adapt the generation of assembler sources via tools/binfile to include
the new home of ASM_INT().
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Michal Orzel <michal.orzel@amd.com>
The rwlock handling is limiting the number of cpus to 4095 today. The
main reason is the use of the atomic_t data type for the main lock
handling, which needs 2 bits for the locking state (writer waiting or
write locked), 12 bits for the id of a possible writer, and a 12 bit
counter for readers. The limit isn't 4096 due to an off by one sanity
check.
The atomic_t data type is 32 bits wide, so in theory 15 bits for the
writer's cpu id and 15 bits for the reader count seem to be fine, but
via read_trylock() more readers than cpus are possible.
This means that it is possible to raise the number of cpus to 16384
without changing the rwlock_t data structure. In order to avoid the
reader count wrapping to zero, don't let read_trylock() succeed in case
the highest bit of the reader's count is set already. This leaves enough
headroom for non-recursive readers to enter without risking a wrap.
While at it calculate _QW_CPUMASK and _QR_SHIFT from _QW_SHIFT and
add a sanity check for not overflowing the atomic_t data type.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Allow 16 bits per cpu number, which is the limit imposed by
spinlock_tickets_t.
This will allow up to 65535 cpus, while increasing only the size of
recursive spinlocks in debug builds from 8 to 12 bytes.
The current Xen limit of 4095 cpus is imposed by SPINLOCK_CPU_BITS
being 12. There are machines available with more cpus than the current
Xen limit, so it makes sense to have the possibility to use more cpus.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Switch the remaining trylock and is_locked variants to return bool.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Recursive and normal spinlocks are sharing the same data structure for
representation of the lock. This has two major disadvantages:
- it is not clear from the definition of a lock, whether it is intended
to be used recursive or not, while a mixture of both usage variants
needs to be
- in production builds (builds without CONFIG_DEBUG_LOCKS) the needed
data size of an ordinary spinlock is 8 bytes instead of 4, due to the
additional recursion data needed (associated with that the rwlock
data is using 12 instead of only 8 bytes)
Fix that by introducing a struct spinlock_recursive for recursive
spinlocks only, and switch recursive spinlock functions to require
pointers to this new struct.
This allows to check the correct usage at build time.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Add rspin_is_locked() and rspin_barrier() in order to prepare differing
spinlock_t and rspinlock_t types.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Add another function level in spinlock.c hiding the spinlock_t layout
from the low level locking code.
This is done in preparation of introducing rspinlock_t for recursive
locks without having to duplicate all of the locking code.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
In order to prepare a type-safe recursive spinlock structure, add
explicitly non-recursive locking functions to be used for non-recursive
locking of spinlocks, which are used recursively, too.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Michal Orzel <michal.orzel@amd.com>
Struct lock_profile contains a pointer to the spinlock it is associated
with. Prepare support of differing spinlock_t and rspinlock_t types by
adding a type indicator of the pointer. Use the highest bit of the
block_cnt member for this indicator in order to not grow the struct
while hurting only the slow path with slightly less performant code.
Note that this requires a cast when printing the value in order to be
format compliant.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Alejandro Vallejo <alejandro.vallejo@cloud.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Instead of special casing rspin_lock_irqsave() and
rspin_unlock_irqrestore() for the console lock, add those functions
to spinlock handling and use them where needed.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Rename the recursive spin_lock() functions by replacing the trailing
"_recursive" with a leading "r".
Switch the parameter to be a pointer to rspinlock_t.
Suggested-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Introduce a new type "rspinlock_t" to be used for recursive spinlocks.
For now it is only an alias of spinlock_t, so both types can still be
used for recursive spinlocks. This will be changed later, though.
Switch all recursive spinlocks to the new type.
Define the initializer helpers and use them where appropriate.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
In xen spinlock code there are several violations of MISRA rule 21.1
(identifiers starting with "__" or "_[A-Z]").
Fix them by using trailing underscores instead.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Add a support statement for the new xen-9pfsd backend. Set it to
"Experimental", as some functionality for Linux guests is missing
(only tested to work with Xenstore-stubdom).
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Add an entry to CHANGELOG.md regarding the new xen-9pfsd daemon.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
With 9pfs now available in Xenstore-stubdom, there is no reason to
have distinct do_control_memreport() variants for the daemon and the
stubdom implementations.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
With 9pfs being fully available in Xenstore-stubdom now, there is no
reason to not fully support all logging capabilities in stubdom.
Open the logfile on stubdom only after the 9pfs file system has been
mounted.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Add some helpers for handling filenames which might need different
implementations between stubdom and daemon environments:
- expansion of relative filenames (those are not really defined today,
just expand them to be relative to /var/lib/xen/xenstore)
- expansion of xenstore_daemon_rundir() (used e.g. for saving the state
file in case of live update - needs to be unchanged in the daemon
case, but should result in /var/lib/xen/xenstore for stubdom)
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Mount the 9pfs device in stubdom enabling it to use files.
This has to happen in a worker thread in order to allow the main thread
handling the required Xenstore accesses in parallel.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Extend the config files of the Xenstore stubdoms to include XENBUS
and 9PFRONT items in order to support file based logging.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Acked-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
With 9pfs now available in Xenstore-stubdom, there is no reason to
have distinct do_control_memreport() variants for the daemon and the
stubdom implementations.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
With 9pfs being fully available in Xenstore-stubdom now, there is no
reason to not fully support all logging capabilities in stubdom.
Open the logfile on stubdom only after the 9pfs file system has been
mounted.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Add some helpers for handling filenames which might need different
implementations between stubdom and daemon environments:
- expansion of relative filenames (those are not really defined today,
just expand them to be relative to /var/lib/xen/xenstore)
- expansion of xenstore_daemon_rundir() (used e.g. for saving the state
file in case of live update - needs to be unchanged in the daemon
case, but should result in /var/lib/xen/xenstore for stubdom)
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Mount the 9pfs device in stubdom enabling it to use files.
This has to happen in a worker thread in order to allow the main thread
handling the required Xenstore accesses in parallel.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Add a 9pfs device to Xenstore stubdom in order to allow it to do e.g.
logging into a dom0 file.
Use the following parameters for the new device:
- tag = "Xen"
- type = "xen_9pfsd"
- path = "/var/lib/xen/xenstore"
- security-model = "none"
For now don't limit allowed file space or number of files.
Add a new libxl function for adding it similar to the function for
adding the console device.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Extend the config files of the Xenstore stubdoms to include XENBUS
and 9PFRONT items in order to support file based logging.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Acked-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Add support for the new 9pfs backend "xen_9pfsd". For this backend type
the tag defaults to "Xen" and the host side path to
"/var/log/xen/guests/<dom-name>".
Do most of the default settings in libxl. Unfortunately the default
path can't easily be set in libxl, as the domain name isn't available
in the related 9pfs specific function.
Settings the defaults in libxl requires to move the sanity checking
of 9pfs parameters from xl to libxl, too.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Make the backend type of 9pfs PV devices configurable. The default is
"qemu" with the related Xenstore backend-side directory being "9pfs".
Add another type "xen_9pfsd" with the related Xenstore backend-side
directory "xen_9pfs".
As additional security features it is possible to specify:
- "max-space" for limiting the maximum space consumed on the filesystem
in MBs
- "max-files" for limiting the maximum number of files in the
filesystem
- "max-open-files" for limiting the maximum number of concurrent open
files
For convenience "auto-delete" is available to let the backend delete the
oldest file of the guest in case otherwise "max-space" or "max-files"
would be violated.
The xen-9pfsd daemon will be started by libxenlight automatically when
the first "xen_9pfs" device is being created.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Acked-by: George Dunlap <george.dunlap@cloud.com> # Golang bits
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
In xen-9pfsd fill_data() va_end() needs to be called before returning.
Coverity Id CID 1592145
Fixes: bcec59cf7f ("tools/xen-9pfsd: add 9pfs version request support")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Add the attach request of the 9pfs protocol. This introduces the "fid"
scheme of the 9pfs protocol.
As this will be needed later, use a dedicated memory allocation
function in alloc_fid() and prepare a fid reference count.
For filling the qid data take the approach from the qemu 9pfs backend
implementation.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Add the version request of the 9pfs protocol. For the version use the
"9P2000.u" variant, as it is supported by Mini-OS and Linux.
For the request parsing add all format items needed even in future in
order to avoid code churn for those additions later.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Add support for generation a 9pfs protocol response via a format based
approach.
Strings are stored in a per device string buffer and they are
referenced via their offset in this buffer. This allows to avoid
having to dynamically allocate memory for each single string.
As a first user of the response handling add a generic p9_error()
function which will be used to return any error to the client.
Add all format parsing variants in order to avoid additional code churn
later when adding the users of those variants. Prepare a special case
for the "read" case already (format character 'D'): in order to avoid
adding another buffer for read data support doing the read I/O directly
into the response buffer.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Add the transport layer of 9pfs. This is basically the infrastructure
to receive requests from the frontend and to send the related answers
via the rings.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Add "xen-9pfsd", a new 9pfs daemon meant to support infrastructure
domains (e.g. xenstore-stubdom) to access files in dom0.
For now only add the code needed for starting the daemon and
registering it with Xenstore via a new "libxl/xen-9pfs/state" node by
writing the "running" state to it.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Today the CODING_STYLE contains a section "Handling unexpected
conditions" specific to the hypervisor. This section is kind of
misplaced for a coding style. It should rather be part of a "Coding
best practices" guide.
Add such a guide as docs/process/coding-best-practices.pandoc and
move the mentioned section from CODING_STYLE to the new file, while
converting the format to pandoc.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
When running as stubdom, map the stubdom's Xenstore ring page in order
to support using the 9pfs frontend.
Use the same pattern as in dom0_init() when running as daemon in dom0
(introduce the own domain, then send an event to the client side to
signal Xenstore is ready to communicate).
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Today domain_init() is called either just before calling dom0_init()
in case no live update is being performed, or it is called after
reading the global state from read_state_global(), as the event
channel fd is needed.
Split up domain_init() into a preparation part which can be called
unconditionally, and in a part setting up the event channel handle.
Note that there is no chance that chk_domain_generation() can be
called now before xc_handle has been setup, so there is no need for
the related special case anymore.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
When [un]mapping the ring page of a Xenstore client, different actions
are required for "normal" guests and dom0. Today this distinction is
made at call site.
Move this distinction into [un]map_interface() instead, avoiding code
duplication and preparing special handling for [un]mapping the stub
domain's ring page.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
All of the socket handling is needed only when running as daemon.
Move it into posix.c, allowing to remove the NO_SOCKETS macro.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
All of the log-pipe handling is needed only when running as daemon.
Move it into posix.c. This requires to have a service function in the
main event loop for handling the related requests and one for setting
the fds[] array, which is renamed to poll_fds to have a more specific
name. Use a generic name for those functions, as socket handling can
be added to them later, too.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Move systemd handling to a new late_init() function in posix.c.
This prepares a future removal of the NO_SOCKETS macro.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Some xenstored initialization needs to be done in the daemon case only,
so split it out into a new early_init() function being a stub in the
stubdom case.
Remove the call of talloc_enable_leak_report_full(), as it serves no
real purpose: the daemon only ever exits due to a crash, in which case
a log of talloc()ed memory hardly has any value.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Rename the xenbus_evtchn() function to get_xenbus_evtchn() in order to
avoid two externally visible symbols with the same name when Xenstore-
stubdom is being built with a Mini-OS with CONFIG_XENBUS set.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
In order to prepare support of PV frontends in xenstore-stubdom, add
allocation of a Xenstore event channel to init-xenstore-domain.c.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Add some optional additional backend paths for 9pfs PV devices. Those
paths will be supported by the new xen-9pfsd 9pfs backend.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
With include/xen/unaligned.h now dealing properly with unaligned
accesses for all architectures, asm/unaligned.h can be removed and
users can be switched to include xen/unaligned.h instead.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Juergen Gross