We're about to enable the use of O_DIRECT in the migration code and
due to the alignment restrictions imposed by filesystems we need to
make sure the flag is only used when doing aligned IO.
The migration will do parallel IO to different regions of a file, so
we need to use more than one file descriptor. Those cannot be obtained
by duplicating (dup()) since duplicated file descriptors share the
file status flags, including O_DIRECT. If one migration channel does
unaligned IO while another sets O_DIRECT to do aligned IO, the
filesystem would fail the unaligned operation.
The add-fd QMP command along with the fdset code are specifically
designed to allow the user to pass a set of file descriptors with
different access flags into QEMU to be later fetched by code that
needs to alternate between those flags when doing IO.
Extend the fdset matching to behave the same with the O_DIRECT flag.
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
I'm keeping the EACCES because callers expect to be able to look at
errno.
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Remove fds right away instead of setting the ->removed flag. We don't
need the extra complexity of having a cleanup function reap the
removed entries at a later time.
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
monitor_fdsets_cleanup() currently has three responsibilities:
1- Remove the fds that have been marked for removal(->removed=true) by
qmp_remove_fd(). This is overly complicated, but ok.
2- Remove any file descriptors that have been passed into QEMU and
never duplicated[1,2]. A file descriptor without duplicates
indicates that no part of QEMU has made use of it. This is
problematic because the current implementation does it only if the
guest is not running and the monitor is closed.
3- Remove/free fdsets that have become empty due to the above
removals. This is ok.
The scenario described in (2) is starting to show some cracks now that
we're trying to consume fds from the migration code:
- Doing cleanup every time the last monitor connection closes works to
reap unused fds, but also has the side effect of forcing the
management layer to pass the file descriptors again in case of a
disconnect/re-connect, if that happened to be the only monitor
connection.
Another side effect is that removing an fd with qmp_remove_fd() is
effectively delayed until the last monitor connection closes.
The usage of mon_refcount is also problematic because it's racy.
- Checking runstate_is_running() skips the cleanup unless the VM is
running and avoids premature cleanup of the fds, but also has the
side effect of blocking the legitimate removal of an fd via
qmp_remove_fd() if the VM happens to be in another state.
This affects qmp_remove_fd() and qmp_query_fdsets() in particular
because requesting a removal at a bad time (guest stopped) might
cause an fd to never be removed, or to be removed at a much later
point in time, causing the query command to continue showing the
supposedly removed fd/fdset.
Note that file descriptors that *have* been duplicated are owned by
the code that uses them and will be removed after qemu_close() is
called. Therefore we've decided that the best course of action to
avoid the undesired side-effects is to stop managing non-duplicated
file descriptors.
1- efb87c1697 ("monitor: Clean up fd sets on monitor disconnect")
2- ebe52b592d ("monitor: Prevent removing fd from set during init")
Reviewed-by: Peter Xu <peterx@redhat.com>
[fix logic mistake: s/fdset_free/fdset_free_if_empty]
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Introduce new functions to remove and free no longer used fds and
fdsets.
We need those to decouple the remove/free routines from
monitor_fdset_cleanup() which will go away in the next patches.
The new functions:
- monitor_fdset_free/_if_empty() will be used when a monitor
connection closes and when an fd is removed to cleanup any fdset
that is now empty.
- monitor_fdset_fd_free() will be used to remove one or more fds that
have been explicitly targeted by qmp_remove_fd().
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Those functions are not needed, one remove function should already
work. Clean it up.
Here the code doesn't really care about whether we need to keep that dupfd
around if close() failed: when that happens something got very wrong,
keeping the dup_fd around the fdsets may not help that situation so far.
Cc: Dr. David Alan Gilbert <dave@treblig.org>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Philippe Mathieu-Daudé <philmd@linaro.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
[add missing return statement, removal during traversal is not safe]
Signed-off-by: Fabiano Rosas <farosas@suse.de>
This is a counterpart to the HMP "info pic" command. It is being
added with an "x-" prefix because this QMP command is intended as an
adhoc debugging tool and will thus not be modelled in QAPI as fully
structured data, nor will it have long term guaranteed stability.
The existing HMP command is rewritten to call the QMP command.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20240610063518.50680-3-philmd@linaro.org>
Replace Monitor API by HumanReadableText one (see commit f2de406f29
"docs/devel: document expectations for QAPI data modelling for QMP"
for rationale).
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20240610063518.50680-2-philmd@linaro.org>
Introduce a new Kconfig symbol, CONFIG_DEVICE_TREE, that specifies whether
to include the common device tree code in system/device_tree.c and to
link to libfdt. For now, include it unconditionally if libfdt is
available.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The whole RDMA subsystem was deprecated in commit e9a54265f5
("hw/rdma: Deprecate the pvrdma device and the rdma subsystem")
released in v8.2.
Remove:
- PVRDMA device
- generated vmw_pvrdma/ directory from linux-headers
- rdmacm-mux tool from contrib/
Cc: Yuval Shaia <yuval.shaia.ml@gmail.com>
Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20240328130255.52257-2-philmd@linaro.org>
QMP is irrelevant for user emulation. Extract the code
related to QMP in a different source file, which won't
be build for user emulation binaries. This avoid pulling
pointless code.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240404194757.9343-5-philmd@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <20240408155330.522792-7-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In qemu monitor mode, when we use gpa2hva command to print the host
virtual address corresponding to a guest physical address, if the gpa is
not in RAM, the error message is below:
(qemu) gpa2hva 0x750000000
Memory at address 0x750000000is not RAM
A space is missed between '0x750000000' and 'is'.
Signed-off-by: Yao Xingtao <yaoxt.fnst@fujitsu.com>
Fixes: e9628441df ("hmp: gpa2hva and gpa2hpa hostaddr command")
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Dr. David Alan Gilbert <dave@treblig.org>
Message-ID: <20240319021610.2423844-1-ruansy.fnst@fujitsu.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Include "exec/memory.h" in order to avoid:
monitor/hmp-cmds-target.c:263:10: error: call to undeclared function 'memory_region_is_ram';
ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
if (!memory_region_is_ram(mrs.mr) && !memory_region_is_romd(mrs.mr)) {
^
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
monitor_qmp_dispatcher_co() runs in the iohandler AioContext that is not
polled during nested event loops. The coroutine currently reschedules
itself in the main loop's qemu_aio_context AioContext, which is polled
during nested event loops. One known problem is that QMP device-add
calls drain_call_rcu(), which temporarily drops the BQL, leading to all
sorts of havoc like other vCPU threads re-entering device emulation code
while another vCPU thread is waiting in device emulation code with
aio_poll().
Paolo Bonzini suggested running non-coroutine QMP handlers in the
iohandler AioContext. This avoids trouble with nested event loops. His
original idea was to move coroutine rescheduling to
monitor_qmp_dispatch(), but I resorted to moving it to qmp_dispatch()
because we don't know if the QMP handler needs to run in coroutine
context in monitor_qmp_dispatch(). monitor_qmp_dispatch() would have
been nicer since it's associated with the monitor implementation and not
as general as qmp_dispatch(), which is also used by qemu-ga.
A number of qemu-iotests need updated .out files because the order of
QMP events vs QMP responses has changed.
Solves Issue #1933.
Cc: qemu-stable@nongnu.org
Fixes: 7bed89958b ("device_core: use drain_call_rcu in in qmp_device_add")
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=2215192
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=2214985
Buglink: https://issues.redhat.com/browse/RHEL-17369
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20240118144823.1497953-4-stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Tested-by: Fiona Ebner <f.ebner@proxmox.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Improve
(qemu) sync-profile of
Error: Invalid parameter 'of'
to
Error: invalid parameter 'of', expecting 'on', 'off', or 'reset'
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20231031111059.3407803-3-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Dr. David Alan Gilbert <dave@treblig.org>
Used by the hv-balloon driver for (optional) guest memory status reports.
Acked-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
GLib recommend to use G_SOURCE_REMOVE / G_SOURCE_CONTINUE
for GSourceFunc callbacks. Our FEWatchFunc is a GSourceFunc
returning such value. Use such definitions which are
"more memorable" [*].
[*] https://docs.gtk.org/glib/callback.SourceFunc.html#return-value
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20230705133139.54419-5-philmd@linaro.org>
We use the user_ss[] array to hold the user emulation sources,
and the softmmu_ss[] array to hold the system emulation ones.
Hold the latter in the 'system_ss[]' array for parity with user
emulation.
Mechanical change doing:
$ sed -i -e s/softmmu_ss/system_ss/g $(git grep -l softmmu_ss)
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230613133347.82210-10-philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Since we *might* have user emulation with softmmu,
use the clearer 'CONFIG_SYSTEM_ONLY' key to check
for system emulation.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230613133347.82210-9-philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
qatomic_mb_read and qatomic_mb_set were the very first atomic primitives
introduced for QEMU; their semantics are unclear and they provide a false
sense of safety.
The last use of qatomic_mb_read() has been removed, so delete it.
qatomic_mb_set() instead can survive as an optimized
qatomic_set()+smp_mb(), similar to Linux's smp_store_mb(), but
rename it to qatomic_set_mb() to match the order of the two
operations.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Instead of relying on magic memory barriers, document the pattern that
is being used. It is the one based on Dekker's algorithm, and in this
case it is embodied as follows:
enqueue request; sleeping = true;
smp_mb(); smp_mb();
if (sleeping) kick(); if (!have a request) yield();
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use a continue statement so that "after going to sleep" is treated the same
way as "after processing a request". Pull the monitor_lock critical
section out of monitor_qmp_requests_pop_any_with_lock() and protect
qmp_dispatcher_co_shutdown with the monitor_lock.
The two changes are complex to separate because monitor_qmp_dispatcher_co()
previously had a complicated logic to check for shutdown both before
and after going to sleep.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Instead of overloading qmp_dispatcher_co_busy, make the coroutine
pointer NULL. This will make things break spectacularly if somebody
tries to start a request after monitor_cleanup().
AIO_WAIT_WHILE_UNLOCKED() does not need qatomic_mb_read(), because
the macro contains all the necessary memory barriers.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Clean up monitor_event to just use monitor_suspend/monitor_resume,
using mon->mux_out to protect against incorrect nesting (especially
on startup).
The only remaining case of reading suspend_cnt is in the can_read
callback, which is just advisory and can use qatomic_read.
As an extra benefit, mux_out is now simply protected by mon_lock.
Also, moving the prompt to the beginning of the main loop removes
it from the output in some error cases where QEMU does not actually
start successfully. It is not a full fix and it would be nice to
also remove the monitor heading, but this is already a small (though
unintentional) improvement.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Allow flushing and printing to the monitor while mon->mon_lock is
held. This will help cleaning up the locking of mon->mux_out and
mon->suspend_cnt.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move monitor_resume()'s call to readline_show_prompt() outside the
potentially locked section. Reuse the existing monitor_accept_input()
bottom half for this purpose.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
monitor_cleanup() is called from the main loop thread. Calling
AIO_WAIT_WHILE(qemu_get_aio_context(), ...) from the main loop thread is
equivalent to AIO_WAIT_WHILE_UNLOCKED(NULL, ...) because neither unlocks
the AioContext and the latter's assertion that we're in the main loop
succeeds.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230309190855.414275-7-stefanha@redhat.com>
Reviewed-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The HMP monitor runs in the main loop thread. Calling
AIO_WAIT_WHILE(qemu_get_aio_context(), ...) from the main loop thread is
equivalent to AIO_WAIT_WHILE_UNLOCKED(NULL, ...) because neither unlocks
the AioContext and the latter's assertion that we're in the main loop
succeeds.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230309190855.414275-6-stefanha@redhat.com>
Reviewed-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Currently, the function will simply fail if ancillary fds are not
provided, for ex on unsupported platforms.
This changes the failure from:
{"error": {"class": "GenericError", "desc": "No file descriptor
supplied via SCM_RIGHTS"}}
to:
{"error": {"class": "CommandNotFound", "desc": "The command getfd
has not been found"}}
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
A process with enough capabilities can duplicate a socket to QEMU. Add a
QMP command to import it and add it to the monitor fd list, so it can be
later used by other commands.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230306122751.2355515-9-marcandre.lureau@redhat.com>
As per comment, presumably to avoid syscall in critical section.
Fixes: 0210c3b39b ("monitor: Use LOCK_GUARD macros")
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230306122751.2355515-7-marcandre.lureau@redhat.com>
Whether it is SPICE, VNC, D-Bus, or the socket chardev, they all
actually expect a socket kind or will fail in different ways at runtime.
Throw an error early if the given 'add_client' fd is not a socket, and
close it to avoid leaks.
This allows to replace the close() call with a more correct & portable
closesocket() version.
(this will allow importing sockets on Windows with a specialized command
in the following patch, while keeping the remaining monitor associated
sockets/add_client code & usage untouched)
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230306122751.2355515-6-marcandre.lureau@redhat.com>
The auto completion does not work in some cases.
Case 1.
1. (qemu) info reg
2. Press 'Tab'.
3. It does not auto complete.
Case 2.
1. (qemu) block_resize flo
2. Press 'Tab'.
3. It does not auto complete 'floppy0'.
Since the readline_add_completion_of() may add any completion when
strlen(pfx) is zero, we remove the check with (name[0] == '\0') because
strlen() always returns zero in that case.
Fixes: 52f50b1e9f ("readline: Extract readline_add_completion_of() from monitor")
Cc: Joe Jin <joe.jin@oracle.com>
Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Message-Id: <20230207045241.8843-1-dongli.zhang@oracle.com>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
What's left in misc.c is exactly the target-dependent part of the HMP
core. Rename accordingly.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230124121946.1139465-33-armbru@redhat.com>
This requires giving them external linkage. Rename do_help_cmd() to
hmp_help(), and do_print() to hmp_print().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230124121946.1139465-30-armbru@redhat.com>
Target-independent hmp_gpa2hva(), hmp_gpa2hpa() move along to stay
next to hmp_gva2gpa().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230124121946.1139465-29-armbru@redhat.com>
monitor_putc() will soon be used from more than one .c file.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230124121946.1139465-28-armbru@redhat.com>
This moves the completion code from MAINTAINERS sections "Human
Monitor (HMP)" and "QMP" to section "QOM".
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230124121946.1139465-26-armbru@redhat.com>
This moves the command from MAINTAINERS section "QMP" to section
"ACPI/SMBIOS)".
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230124121946.1139465-25-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
This moves these commands from MAINTAINERS section "Human
Monitor (HMP)" to section "Stats".
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230124121946.1139465-24-armbru@redhat.com>
This moves these commands from MAINTAINERS section "QMP" to new
section "Stats". Status is Orphan. Volunteers welcome!
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230124121946.1139465-23-armbru@redhat.com>
This moves these commands from MAINTAINERS section "Human
Monitor (HMP)" and "QMP" to "Main loop".
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230124121946.1139465-22-armbru@redhat.com>
