Commit Graph

14 Commits

Author SHA1 Message Date
Marcel Apfelbaum 06329ccecf mem: add share parameter to memory-backend-ram
Currently only file backed memory backend can
be created with a "share" flag in order to allow
sharing guest RAM with other processes in the host.

Add the "share" flag also to RAM Memory Backend
in order to allow remapping parts of the guest RAM
to different host virtual addresses. This is needed
by the RDMA devices in order to remap non-contiguous
QEMU virtual addresses to a contiguous virtual address range.

Moved the "share" flag to the Host Memory base class,
modified phys_mem_alloc to include the new parameter
and a new interface memory_region_init_ram_shared_nomigrate.

There are no functional changes if the new flag is not used.

Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Marcel Apfelbaum <marcel@redhat.com>
2018-02-19 13:03:24 +02:00
Haozhong Zhang 9837684316 hostmem-file: add "align" option
When mmap(2) the backend files, QEMU uses the host page size
(getpagesize(2)) by default as the alignment of mapping address.
However, some backends may require alignments different than the page
size. For example, mmap a device DAX (e.g., /dev/dax0.0) on Linux
kernel 4.13 to an address, which is 4K-aligned but not 2M-aligned,
fails with a kernel message like

[617494.969768] dax dax0.0: qemu-system-x86: dax_mmap: fail, unaligned vma (0x7fa37c579000 - 0x7fa43c579000, 0x1fffff)

Because there is no common approach to get such alignment requirement,
we add the 'align' option to 'memory-backend-file', so that users or
management utils, which have enough knowledge about the backend, can
specify a proper alignment via this option.

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Message-Id: <20171211072806.2812-2-haozhong.zhang@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
[ehabkost: fixed typo, fixed error_setg() format string]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2018-01-19 11:18:51 -02:00
Eduardo Habkost 11ae6ed8af hostmem-file: Add "discard-data" option
The new option can be used to indicate that the file contents can
be destroyed and don't need to be flushed to disk when QEMU exits
or when the memory backend object is removed.

Internally, it will trigger a madvise(MADV_REMOVE) call when the
memory backend is removed.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20170824192315.5897-4-ehabkost@redhat.com>
[ehabkost: fixup: improved documentation]
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Tested-by: Zack Cornelius <zack.cornelius@kove.net>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2017-09-19 09:09:23 -03:00
Peter Xu 6f4c60e47f hostmem: use host_memory_backend_mr_inited() where proper
Use the new interface to boost readability.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1489151370-15453-3-git-send-email-peterx@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2017-04-20 15:22:41 -03:00
Eduardo Habkost 026ac483c7 hostmem-file: Register TYPE_MEMORY_BACKEND_FILE properties as class properties
To do the conversion, the file_backend_class_init() was moved
after the getter/setter functions. The old
file_backend_instance_init() function was removed because it is
not needed anymore.

The NULL errp arguments on the property registration calls were
changed to &error_abort.

Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2016-10-17 15:48:40 -02:00
Marc-André Lureau bc78a01319 hostmem-file: plug a small leak
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1460566660-19241-1-git-send-email-marcandre.lureau@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-04-15 17:56:06 +02:00
Gonglei 696b55017d hostmem-file: fix memory leak
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Message-Id: <1456998223-12356-5-git-send-email-arei.gonglei@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-04-08 00:07:56 +02:00
Markus Armbruster da34e65cb4 include/qemu/osdep.h: Don't include qapi/error.h
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the
Error typedef.  Since then, we've moved to include qemu/osdep.h
everywhere.  Its file comment explains: "To avoid getting into
possible circular include dependencies, this file should not include
any other QEMU headers, with the exceptions of config-host.h,
compiler.h, os-posix.h and os-win32.h, all of which are doing a
similar job to this file and are under similar constraints."
qapi/error.h doesn't do a similar job, and it doesn't adhere to
similar constraints: it includes qapi-types.h.  That's in excess of
100KiB of crap most .c files don't actually need.

Add the typedef to qemu/typedefs.h, and include that instead of
qapi/error.h.  Include qapi/error.h in .c files that need it and don't
get it now.  Include qapi-types.h in qom/object.h for uint16List.

Update scripts/clean-includes accordingly.  Update it further to match
reality: replace config.h by config-target.h, add sysemu/os-posix.h,
sysemu/os-win32.h.  Update the list of includes in the qemu/osdep.h
comment quoted above similarly.

This reduces the number of objects depending on qapi/error.h from "all
of them" to less than a third.  Unfortunately, the number depending on
qapi-types.h shrinks only a little.  More work is needed for that one.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
[Fix compilation without the spice devel packages. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:15 +01:00
Peter Maydell 9c058332f3 backends: 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: 1454089805-5470-5-git-send-email-peter.maydell@linaro.org
2016-02-04 17:01:04 +00:00
Daniel P. Berrange ef1e1e0782 maint: avoid useless "if (foo) free(foo)" pattern
The free() and g_free() functions both happily accept
NULL on any platform QEMU builds on. As such putting a
conditional 'if (foo)' check before calls to 'free(foo)'
merely serves to bloat the lines of code.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-09-11 10:21:38 +03:00
Jan Kiszka c2cb2b041b hostmem: Fix mem-path property name in error report
The subtle difference between "property not found" and "property not
set" is already confusing enough.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-04-30 16:05:48 +03:00
Paolo Bonzini dbcb898118 hostmem: add property to map memory with MAP_SHARED
A new "share" property can be used with the "memory-file" backend to
map memory with MAP_SHARED instead of MAP_PRIVATE.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-19 18:44:20 +03:00
Paolo Bonzini a35ba7be4b hostmem: allow preallocation of any memory region
And allow preallocation of file-based memory even without -mem-prealloc.
Some care is necessary because -mem-prealloc does not allow disabling
preallocation for hostmem-file.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-19 18:44:20 +03:00
Paolo Bonzini 52330e1a96 hostmem: add file-based HostMemoryBackend
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

MST: comment tweak
2014-06-19 18:44:20 +03:00