Commit Graph

12 Commits

Author SHA1 Message Date
ryang 900610e631 module: Use QEMU_MODULE_DIR as a search path
The current paths for modules are CONFIG_QEMU_MODDIR and paths relative
to the executable. Qemu and its modules can be installed and executed in
paths that are different from these search paths. This change allows
a search path to be specified by environment variable.

An example usage for this is postmarketOS[1]. This is a build environment
for Alpine Linux. It sets up Alpine Linux in a chroot environment.
Alpine's Qemu packages are installed in the chroot. The Alpine Linux Qemu
package is used to test compiled Alpine Linux system images. This way there
isn't a reliance on the which ever version of Qemu the host system / distro
provides.

postmarketOS executes Qemu on host system outside of the chroot
The Qemu module search path needs to point to the location of the
chroot relative to the host system.

e.g.
The root of the Alpine Linux chroot is:
~/.local/var/pmbootstrap/chroot_native/

Alpine's Qemu is installed at
~/.local/var/pmbootstrap/chroot_native/usr/bin/

The Qemu module search path needs to be:
QEMU_MODULE_DIR=~/.local/var/pmbootstrap/chroot_native/usr/lib/qemu/

[1] https://postmarketos.org/

Signed-off-by: ryang <decatf@gmail.com>
Message-Id: <20180704181010.GA918@computer>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-23 18:46:25 +02:00
Fam Zheng dffa41b486 module: Don't load the same module if requested multiple times
Use a hash table to keep record of all loaded modules, and return early
if the requested module is already loaded.

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 1473043845-13197-3-git-send-email-famz@redhat.com
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-10-07 14:14:06 +02:00
Marc Mari 88d88798b7 blockdev: Add dynamic module loading for block drivers
Extend the current module interface to allow for block drivers to be
loaded dynamically on request. The only block drivers that can be
converted into modules are the drivers that don't perform any init
operation except for registering themselves.

In addition, only the protocol drivers are being modularized, as they
are the only ones which see significant performance benefits. The format
drivers do not generally link to external libraries, so modularizing
them is of no benefit from a performance perspective.

All the necessary module information is located in a new structure found
in module_block.h

This spoils the purpose of 5505e8b76f (block/dmg: make it modular).

Before this patch, if module build is enabled, block-dmg.so is linked to
libbz2, whereas the main binary is not. In downstream, theoretically, it
means only the qemu-block-extra package depends on libbz2, while the
main QEMU package needn't to. With this patch, we (temporarily) change
the case so that the main QEMU depends on libbz2 again.

Signed-off-by: Marc Marí <markmb@redhat.com>
Signed-off-by: Colin Lord <clord@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1471008424-16465-4-git-send-email-clord@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
[mreitz: Do a signed comparison against the length of
 block_driver_modules[], so it will not cause a compile error when
 empty]
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-09-20 22:12:03 +02:00
Eduardo Habkost 9be385980d coccinelle: Remove unnecessary variables for function return value
Use Coccinelle script to replace 'ret = E; return ret' with
'return E'. The script will do the substitution only when the
function return type and variable type are the same.

Manual fixups:

* audio/audio.c: coding style of "read (...)" and "write (...)"
* block/qcow2-cluster.c: wrap line to make it shorter
* block/qcow2-refcount.c: change indentation of wrapped line
* target-tricore/op_helper.c: fix coding style of
  "remainder|quotient"
* target-mips/dsp_helper.c: reverted changes because I don't
  want to argue about checkpatch.pl
* ui/qemu-pixman.c: fix line indentation
* block/rbd.c: restore blank line between declarations and
  statements

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <1465855078-19435-4-git-send-email-ehabkost@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Unused Coccinelle rule name dropped along with a redundant comment;
whitespace touched up in block/qcow2-cluster.c; stale commit message
paragraph deleted]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-06-20 16:38:13 +02:00
Peter Maydell aafd758410 util: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1454089805-5470-6-git-send-email-peter.maydell@linaro.org
2016-02-04 17:01:04 +00:00
Andreas Färber bb2eb1892d module: Don't complain when a module is absent
The current implementation depends on a configure-time generated list of
block modules. When any of them is absent, module_load() emits a warning.

This is suboptimal because extracting code to modules was mainly done to
allow separate packaging of modules with intrusive dependencies. Absence
of optional packages then leads to absence of modules and an error
message, which users may recognize as new and report as error.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-18 14:57:35 +02:00
Andreas Färber f9e13f8fd8 module: Simplify module_load()
The file path is not used for error reporting, so we can free it
directly after use.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-18 14:57:35 +02:00
Stefan Weil 08cf99629d util: Add 'static' attribute to function implementation
The static code analyzer smatch complains because of a missing 'static'
attribute:

util/module.c:166:6: warning:
 symbol 'module_load' was not declared. Should it be static?

'static' is used in the forward declaration, but not in the implementation.
Add it there, too.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-03-27 19:22:48 +04:00
Fam Zheng d844a7b656 modules: Fix building with --enable-modules
Compiling util/modules.c with modules enabled fails now.

Fix it by including qemu-common.h before #ifdef testing in module.c.

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 1393453893-12125-1-git-send-email-famz@redhat.com
Reviewed-by: Hu Tao <hutao@cn.fujitsu.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-02-28 12:30:13 +00:00
Paolo Bonzini aa0d1f4488 modules: do not include gmodule-2.0 in static builds
gmodule-2.0's pkg-config files include -Wl,--export-dynamic, which breaks
static builds.  It is a glib bug, but we need to support --static builds for
the linux-user targets, and in the end all that is needed to fix this is:

* outlaw --enable-modules --static, which makes little sense anyway

* only include gmodule-2.0's cflags and ldflags if --enable-modules is
specified on the command line.

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1393346215-5636-1-git-send-email-pbonzini@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-02-25 18:34:28 +00:00
Fam Zheng e26110cfc6 module: implement module loading
This patch adds loading, stamp checking and initialization of modules.

The init function of dynamic module is no longer directly called as
__attribute__((constructor)) in static linked version, it is called
only after passed the checking of presense of stamp symbol:

    qemu_stamp_$RELEASEHASH

where $RELEASEHASH is generated by hashing version strings and content
of configure script.

With this, modules built from a different tree/version/configure will
not be loaded.

The module loading code requires gmodule-2.0.

Modules are searched under
 - CONFIG_MODDIR
 - executable folder (to allow running qemu-{img,io} in the build
   directory)
 - ../ of executable folder (to allow running system emulator in the
   build directory)

Modules are linked under their subdir respectively, then copied to top
level of build directory for above convinience, e.g.:
    $(BUILD_DIR)/block/curl.so -> $(BUILD_DIR)/block-curl.so

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-02-20 13:14:18 +01:00
Paolo Bonzini baacf04799 build: move libqemuutil.a components to util/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-01-12 18:42:50 +01:00