Commit Graph

41 Commits

Author SHA1 Message Date
David Hildenbrand
9181fb7043 hostmem: Wire up RAM_NORESERVE via "reserve" property
Let's provide a way to control the use of RAM_NORESERVE via memory
backends using the "reserve" property which defaults to true (old
behavior).

Only Linux currently supports clearing the flag (and support is checked at
runtime, depending on the setting of "/proc/sys/vm/overcommit_memory").
Windows and other POSIX systems will bail out with "reserve=false".

The target use case is virtio-mem, which dynamically exposes memory
inside a large, sparse memory area to the VM. This essentially allows
avoiding to set "/proc/sys/vm/overcommit_memory == 0") when using
virtio-mem and also supporting hugetlbfs in the future.

As really only Linux implements RAM_NORESERVE right now, let's expose
the property only with CONFIG_LINUX. Setting the property to "false"
will then only fail in corner cases -- for example on very old kernels
or when memory overcommit was completely disabled by the admin.

Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Eduardo Habkost <ehabkost@redhat.com> for memory backend and machine core
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Eric Blake <eblake@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210510114328.21835-11-david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-06-15 20:27:38 +02:00
Thomas Huth
4c386f8064 Do not include sysemu/sysemu.h if it's not really necessary
Stop including sysemu/sysemu.h in files that don't need it.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-2-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2021-05-02 17:24:50 +02:00
Michal Privoznik
def835f0da hostmem: Don't report pmem attribute if unsupported
When management applications (like Libvirt) want to check whether
memory-backend-file.pmem is supported they can list object
properties using 'qom-list-properties'. However, 'pmem' is
declared always (and thus reported always) and only at runtime
QEMU errors out if it was built without libpmem (and thus can not
guarantee write persistence). This is suboptimal since we have
ability to declare attributes at compile time.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1915216
Message-Id: <dfcc5dc7e2efc0283bc38e3036da2c0323621cdb.1611647111.git.mprivozn@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2021-02-18 18:34:47 -05:00
Stefan Hajnoczi
86635aa4e9 hostmem-file: add readonly=on|off option
Let -object memory-backend-file work on read-only files when the
readonly=on option is given. This can be used to share the contents of a
file between multiple guests while preventing them from consuming
Copy-on-Write memory if guests dirty the pages, for example.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20210104171320.575838-3-stefanha@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2021-02-01 17:07:34 -05:00
Stefan Hajnoczi
369d6dc4de memory: add readonly support to memory_region_init_ram_from_file()
There is currently no way to open(O_RDONLY) and mmap(PROT_READ) when
creating a memory region from a file. This functionality is needed since
the underlying host file may not allow writing.

Add a bool readonly argument to memory_region_init_ram_from_file() and
the APIs it calls.

Extend memory_region_init_ram_from_file() rather than introducing a
memory_region_init_rom_from_file() API so that callers can easily make a
choice between read/write and read-only at runtime without calling
different APIs.

No new RAMBlock flag is introduced for read-only because it's unclear
whether RAMBlocks need to know that they are read-only. Pass a bool
readonly argument instead.

Both of these design decisions can be changed in the future. It just
seemed like the simplest approach to me.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20210104171320.575838-2-stefanha@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2021-02-01 17:07:34 -05:00
Eduardo Habkost
8063396bf3 Use OBJECT_DECLARE_SIMPLE_TYPE when possible
This converts existing DECLARE_INSTANCE_CHECKER usage to
OBJECT_DECLARE_SIMPLE_TYPE when possible.

$ ./scripts/codeconverter/converter.py -i \
  --pattern=AddObjectDeclareSimpleType $(git grep -l '' -- '*.[ch]')

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Paul Durrant <paul@xen.org>
Message-Id: <20200916182519.415636-6-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-18 14:12:32 -04:00
Eduardo Habkost
8110fa1d94 Use DECLARE_*CHECKER* macros
Generated using:

 $ ./scripts/codeconverter/converter.py -i \
   --pattern=TypeCheckMacro $(git grep -l '' -- '*.[ch]')

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-12-ehabkost@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-13-ehabkost@redhat.com>
Message-Id: <20200831210740.126168-14-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-09 09:27:09 -04:00
Eduardo Habkost
db1015e92e Move QOM typedefs and add missing includes
Some typedefs and macros are defined after the type check macros.
This makes it difficult to automatically replace their
definitions with OBJECT_DECLARE_TYPE.

Patch generated using:

 $ ./scripts/codeconverter/converter.py -i \
   --pattern=QOMStructTypedefSplit $(git grep -l '' -- '*.[ch]')

which will split "typdef struct { ... } TypedefName"
declarations.

Followed by:

 $ ./scripts/codeconverter/converter.py -i --pattern=MoveSymbols \
    $(git grep -l '' -- '*.[ch]')

which will:
- move the typedefs and #defines above the type check macros
- add missing #include "qom/object.h" lines if necessary

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-9-ehabkost@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-10-ehabkost@redhat.com>
Message-Id: <20200831210740.126168-11-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-09 09:26:43 -04:00
Markus Armbruster
668f62ec62 error: Eliminate error_propagate() with Coccinelle, part 1
When all we do with an Error we receive into a local variable is
propagating to somewhere else, we can just as well receive it there
right away.  Convert

    if (!foo(..., &err)) {
        ...
        error_propagate(errp, err);
        ...
        return ...
    }

to

    if (!foo(..., errp)) {
        ...
        ...
        return ...
    }

where nothing else needs @err.  Coccinelle script:

    @rule1 forall@
    identifier fun, err, errp, lbl;
    expression list args, args2;
    binary operator op;
    constant c1, c2;
    symbol false;
    @@
         if (
    (
    -        fun(args, &err, args2)
    +        fun(args, errp, args2)
    |
    -        !fun(args, &err, args2)
    +        !fun(args, errp, args2)
    |
    -        fun(args, &err, args2) op c1
    +        fun(args, errp, args2) op c1
    )
            )
         {
             ... when != err
                 when != lbl:
                 when strict
    -        error_propagate(errp, err);
             ... when != err
    (
             return;
    |
             return c2;
    |
             return false;
    )
         }

    @rule2 forall@
    identifier fun, err, errp, lbl;
    expression list args, args2;
    expression var;
    binary operator op;
    constant c1, c2;
    symbol false;
    @@
    -    var = fun(args, &err, args2);
    +    var = fun(args, errp, args2);
         ... when != err
         if (
    (
             var
    |
             !var
    |
             var op c1
    )
            )
         {
             ... when != err
                 when != lbl:
                 when strict
    -        error_propagate(errp, err);
             ... when != err
    (
             return;
    |
             return c2;
    |
             return false;
    |
             return var;
    )
         }

    @depends on rule1 || rule2@
    identifier err;
    @@
    -    Error *err = NULL;
         ... when != err

Not exactly elegant, I'm afraid.

The "when != lbl:" is necessary to avoid transforming

         if (fun(args, &err)) {
             goto out
         }
         ...
     out:
         error_propagate(errp, err);

even though other paths to label out still need the error_propagate().
For an actual example, see sclp_realize().

Without the "when strict", Coccinelle transforms vfio_msix_setup(),
incorrectly.  I don't know what exactly "when strict" does, only that
it helps here.

The match of return is narrower than what I want, but I can't figure
out how to express "return where the operand doesn't use @err".  For
an example where it's too narrow, see vfio_intx_enable().

Silently fails to convert hw/arm/armsse.c, because Coccinelle gets
confused by ARMSSE being used both as typedef and function-like macro
there.  Converted manually.

Line breaks tidied up manually.  One nested declaration of @local_err
deleted manually.  Preexisting unwanted blank line dropped in
hw/riscv/sifive_e.c.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200707160613.848843-35-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster
dcfe480544 error: Avoid unnecessary error_propagate() after error_setg()
Replace

    error_setg(&err, ...);
    error_propagate(errp, err);

by

    error_setg(errp, ...);

Related pattern:

    if (...) {
        error_setg(&err, ...);
        goto out;
    }
    ...
 out:
    error_propagate(errp, err);
    return;

When all paths to label out are that way, replace by

    if (...) {
        error_setg(errp, ...);
        return;
    }

and delete the label along with the error_propagate().

When we have at most one other path that actually needs to propagate,
and maybe one at the end that where propagation is unnecessary, e.g.

    foo(..., &err);
    if (err) {
        goto out;
    }
    ...
    bar(..., &err);
 out:
    error_propagate(errp, err);
    return;

move the error_propagate() to where it's needed, like

    if (...) {
        foo(..., &err);
        error_propagate(errp, err);
        return;
    }
    ...
    bar(..., errp);
    return;

and transform the error_setg() as above.

In some places, the transformation results in obviously unnecessary
error_propagate().  The next few commits will eliminate them.

Bonus: the elimination of gotos will make later patches in this series
easier to review.

Candidates for conversion tracked down with this Coccinelle script:

    @@
    identifier err, errp;
    expression list args;
    @@
    -    error_setg(&err, args);
    +    error_setg(errp, args);
         ... when != err
         error_propagate(errp, err);

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200707160613.848843-34-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster
62a35aaa31 qapi: Use returned bool to check for failure, Coccinelle part
The previous commit enables conversion of

    visit_foo(..., &err);
    if (err) {
        ...
    }

to

    if (!visit_foo(..., errp)) {
        ...
    }

for visitor functions that now return true / false on success / error.
Coccinelle script:

    @@
    identifier fun =~ "check_list|input_type_enum|lv_start_struct|lv_type_bool|lv_type_int64|lv_type_str|lv_type_uint64|output_type_enum|parse_type_bool|parse_type_int64|parse_type_null|parse_type_number|parse_type_size|parse_type_str|parse_type_uint64|print_type_bool|print_type_int64|print_type_null|print_type_number|print_type_size|print_type_str|print_type_uint64|qapi_clone_start_alternate|qapi_clone_start_list|qapi_clone_start_struct|qapi_clone_type_bool|qapi_clone_type_int64|qapi_clone_type_null|qapi_clone_type_number|qapi_clone_type_str|qapi_clone_type_uint64|qapi_dealloc_start_list|qapi_dealloc_start_struct|qapi_dealloc_type_anything|qapi_dealloc_type_bool|qapi_dealloc_type_int64|qapi_dealloc_type_null|qapi_dealloc_type_number|qapi_dealloc_type_str|qapi_dealloc_type_uint64|qobject_input_check_list|qobject_input_check_struct|qobject_input_start_alternate|qobject_input_start_list|qobject_input_start_struct|qobject_input_type_any|qobject_input_type_bool|qobject_input_type_bool_keyval|qobject_input_type_int64|qobject_input_type_int64_keyval|qobject_input_type_null|qobject_input_type_number|qobject_input_type_number_keyval|qobject_input_type_size_keyval|qobject_input_type_str|qobject_input_type_str_keyval|qobject_input_type_uint64|qobject_input_type_uint64_keyval|qobject_output_start_list|qobject_output_start_struct|qobject_output_type_any|qobject_output_type_bool|qobject_output_type_int64|qobject_output_type_null|qobject_output_type_number|qobject_output_type_str|qobject_output_type_uint64|start_list|visit_check_list|visit_check_struct|visit_start_alternate|visit_start_list|visit_start_struct|visit_type_.*";
    expression list args;
    typedef Error;
    Error *err;
    @@
    -    fun(args, &err);
    -    if (err)
    +    if (!fun(args, &err))
         {
             ...
         }

A few line breaks tidied up manually.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-19-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster
d2623129a7 qom: Drop parameter @errp of object_property_add() & friends
The only way object_property_add() can fail is when a property with
the same name already exists.  Since our property names are all
hardcoded, failure is a programming error, and the appropriate way to
handle it is passing &error_abort.

Same for its variants, except for object_property_add_child(), which
additionally fails when the child already has a parent.  Parentage is
also under program control, so this is a programming error, too.

We have a bit over 500 callers.  Almost half of them pass
&error_abort, slightly fewer ignore errors, one test case handles
errors, and the remaining few callers pass them to their own callers.

The previous few commits demonstrated once again that ignoring
programming errors is a bad idea.

Of the few ones that pass on errors, several violate the Error API.
The Error ** argument must be NULL, &error_abort, &error_fatal, or a
pointer to a variable containing NULL.  Passing an argument of the
latter kind twice without clearing it in between is wrong: if the
first call sets an error, it no longer points to NULL for the second
call.  ich9_pm_add_properties(), sparc32_ledma_realize(),
sparc32_dma_realize(), xilinx_axidma_realize(), xilinx_enet_realize()
are wrong that way.

When the one appropriate choice of argument is &error_abort, letting
users pick the argument is a bad idea.

Drop parameter @errp and assert the preconditions instead.

There's one exception to "duplicate property name is a programming
error": the way object_property_add() implements the magic (and
undocumented) "automatic arrayification".  Don't drop @errp there.
Instead, rename object_property_add() to object_property_try_add(),
and add the obvious wrapper object_property_add().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-15-armbru@redhat.com>
[Two semantic rebase conflicts resolved]
2020-05-15 07:07:58 +02:00
Igor Mammedov
4ebc74dbbf hostmem: fix strict bind policy
When option -mem-prealloc is used with one or more memory-backend
objects, created backends may not obey configured bind policy or
creation may fail after kernel attempts to move pages according
to bind policy.
Reason is in file_ram_alloc(), which will pre-allocate
any descriptor based RAM if global mem_prealloc != 0 and that
happens way before bind policy is applied to memory range.

One way to fix it would be to extend memory_region_foo() API
and add more invariants that could broken later due implicit
dependencies that's hard to track.

Another approach is to drop adhoc main RAM allocation and
consolidate it around memory-backend. That allows to have
single place that allocates guest RAM (main and memdev)
in the same way and then global mem_prealloc could be
replaced by backend's property[s] that will affect created
memory-backend objects but only in correct order this time.

With main RAM now converted to hostmem backends, there is no
point in keeping global mem_prealloc around, so alias
 -mem-prealloc to "memory-backend.prealloc=on"
machine compat[*] property and make mem_prealloc a local
variable to only stir registration of compat property.

*) currently user accessible -global works only with DEVICE
   based objects and extra work is needed to make it work
   with hostmem backends. But that is convenience option
   and out of scope of this already huge refactoring.
   Hence machine compat properties were used.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <20200219160953.13771-78-imammedo@redhat.com>
2020-02-19 16:50:02 +00:00
Igor Mammedov
900c0ba373 machine: alias -mem-path and -mem-prealloc into memory-foo backend
Allow machine to opt in for hostmem backend based initial RAM
even if user uses old -mem-path/prealloc options by providing
  MachineClass::default_ram_id
Follow up patches will incrementally convert machines to new API,
by dropping memory_region_allocate_system_memory() and setting
default_ram_id that board used to use before conversion to keep
migration stream the same.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <20200219160953.13771-4-imammedo@redhat.com>
2020-02-19 16:49:53 +00:00
Stefan Hajnoczi
72d41eb4b8 memory: fetch pmem size in get_file_size()
Neither stat(2) nor lseek(2) report the size of Linux devdax pmem
character device nodes.  Commit 314aec4a6e
("hostmem-file: reject invalid pmem file sizes") added code to
hostmem-file.c to fetch the size from sysfs and compare against the
user-provided size=NUM parameter:

  if (backend->size > size) {
      error_setg(errp, "size property %" PRIu64 " is larger than "
                 "pmem file \"%s\" size %" PRIu64, backend->size,
                 fb->mem_path, size);
      return;
  }

It turns out that exec.c:qemu_ram_alloc_from_fd() already has an
equivalent size check but it skips devdax pmem character devices because
lseek(2) returns 0:

  if (file_size > 0 && file_size < size) {
      error_setg(errp, "backing store %s size 0x%" PRIx64
                 " does not match 'size' option 0x" RAM_ADDR_FMT,
                 mem_path, file_size, size);
      return NULL;
  }

This patch moves the devdax pmem file size code into get_file_size() so
that we check the memory size in a single place:
qemu_ram_alloc_from_fd().  This simplifies the code and makes it more
general.

This also fixes the problem that hostmem-file only checks the devdax
pmem file size when the pmem=on parameter is given.  An unchecked
size=NUM parameter can lead to SIGBUS in QEMU so we must always fetch
the file size for Linux devdax pmem character device nodes.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20190830093056.12572-1-stefanha@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-09-16 12:32:21 +02:00
Stefan Hajnoczi
7faae95ebc hostmem-file: fix pmem file size check
Commit 314aec4a6e ("hostmem-file: reject
invalid pmem file sizes") added a file size check that verifies the
hostmem object's size parameter against the actual devdax pmem file.
This is useful because getting the size wrong results in confusing
errors inside the guest.

However, the code doesn't work properly for files where struct
stat::st_size is zero.  Hostmem-file's ->alloc() function returns early
without setting an Error, causing the following assertion failure:

  qemu/memory.c:2215: memory_region_get_ram_ptr: Assertion `mr->ram_block' failed.

This patch handles the case where qemu_get_pmem_size() returns 0 but
there is no error.

Fixes: 314aec4a6e
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20190823135632.25010-1-stefanha@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2019-09-03 14:39:46 -03:00
Markus Armbruster
0b8fa32f55 Include qemu/module.h where needed, drop it from qemu-common.h
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-4-armbru@redhat.com>
[Rebased with conflicts resolved automatically, except for
hw/usb/dev-hub.c hw/misc/exynos4210_rng.c hw/misc/bcm2835_rng.c
hw/misc/aspeed_scu.c hw/display/virtio-vga.c hw/arm/stm32f205_soc.c;
ui/cocoa.m fixed up]
2019-06-12 13:18:33 +02:00
Stefan Hajnoczi
314aec4a6e hostmem-file: reject invalid pmem file sizes
Guests started with NVDIMMs larger than the underlying host file produce
confusing errors inside the guest.  This happens because the guest
accesses pages beyond the end of the file.

Check the pmem file size on startup and print a clear error message if
the size is invalid.

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1669053
Cc: Wei Yang <richardw.yang@linux.intel.com>
Cc: Zhang Yi <yi.z.zhang@linux.intel.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20190214031004.32522-3-stefanha@redhat.com>
Reviewed-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Pankaj Gupta <pagupta@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2019-03-11 10:44:19 -03:00
Igor Mammedov
5c7ba877ef hostmem-file: simplify ifdef-s in file_backend_memory_alloc()
cleanup file_backend_memory_alloc() by using one CONFIG_POSIX ifdef
instead of several ones within the function to make it simpler to follow.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Suggested-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20190213123858.24620-1-imammedo@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20190214031004.32522-2-stefanha@redhat.com>
[lv: s/hostmem/hostmem-file/]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2019-03-06 11:21:27 +01:00
Zhang Yi
21d1683690 hostmem: add more information in error messages
When there are multiple memory backends in use, including the object type
and property name in the error message can help users to locate the error.

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Signed-off-by: Zhang Yi <yi.z.zhang@linux.intel.com>
Message-Id: <97d9193875747d8378c05b9e3b3cb39c1b7d2b4e.1546399191.git.yi.z.zhang@linux.intel.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
[ehabkost: reword commit message]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2019-01-28 15:52:05 -02:00
Marc-André Lureau
fa0cb34d22 hostmem: use object id for memory region name with >= 4.0
hostmem-file and hostmem-memfd use the whole object path for the
memory region name, and hostname-ram uses only the path component (the
object id, or canonical path basename):

qemu -m 1024 -object memory-backend-file,id=mem,size=1G,mem-path=/tmp/foo -numa node,memdev=mem -monitor stdio
(qemu) info ramblock
              Block Name    PSize              Offset               Used              Total
            /objects/mem    4 KiB  0x0000000000000000 0x0000000040000000 0x0000000040000000

qemu -m 1024 -object memory-backend-memfd,id=mem,size=1G -numa node,memdev=mem -monitor stdio
(qemu) info ramblock
              Block Name    PSize              Offset               Used              Total
            /objects/mem    4 KiB  0x0000000000000000 0x0000000040000000 0x0000000040000000

qemu -m 1024 -object memory-backend-ram,id=mem,size=1G -numa node,memdev=mem -monitor stdio
(qemu) info ramblock
              Block Name    PSize              Offset               Used              Total
                     mem    4 KiB  0x0000000000000000 0x0000000040000000 0x0000000040000000

For consistency, change to use object id for -file and -memfd as well
with >= 4.0.

Having a consistent naming allows to migrate to different hostmem
backends.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: Eduardo Habkost <ehabkost@redhat.com>
2019-01-07 16:18:42 +04:00
Zhang Yi
87dc3ce60a hostmem-file: remove object id from pmem error message
We will never get the canonical path from the object
before object_property_add_child.

Signed-off-by: Zhang Yi <yi.z.zhang@linux.intel.com>
Message-Id: <a6491f996827f4039c1a52198ed5dcc7727cb0f9.1540389255.git.yi.z.zhang@linux.intel.com>
[ehabkost: reword commit message]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2018-12-11 15:45:22 -02:00
Marc-André Lureau
86100290cb hostmem: no need to check for host_memory_backend_mr_inited() in alloc()
memfd_backend_memory_alloc/file_backend_memory_alloc both needlessly
are are calling host_memory_backend_mr_inited() which creates an
illusion that alloc could be called multiple times but it isn't, it's
called once from UserCreatable complete().

Suggested-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-11-28 11:51:24 +01:00
Zhang Yi
a1f3bb1845 hostmem-file: fixed the memory leak while get pmem path.
object_get_canonical_path_component() returns a string which
must be freed using g_free().

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Zhang Yi <yi.z.zhang@linux.intel.com>
Message-Id: <7328fb16c394eaf5d65437d11c2a9343647b6d3d.1535471899.git.yi.z.zhang@linux.intel.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2018-10-24 06:44:59 -03:00
Hikaru Nishida
d5dbde4645 hostmem-file: make available memory-backend-file on POSIX-based hosts
Before this change, memory-backend-file object is valid for Linux hosts
only because hostmem-file.c is compiled only on Linux hosts.
However, other POSIX-based hosts (such as macOS) can support
memory-backend-file object in the same way as on Linux hosts.
This patch makes hostmem-file.c and related functions to be compiled on
all POSIX-based hosts to make available memory-backend-file on them.

Signed-off-by: Hikaru Nishida <hikarupsp@gmail.com>
Message-Id: <20180924123205.29651-1-hikarupsp@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-02 19:09:13 +02:00
Junyan He
a4de8552b2 hostmem-file: add the 'pmem' option
When QEMU emulates vNVDIMM labels and migrates vNVDIMM devices, it
needs to know whether the backend storage is a real persistent memory,
in order to decide whether special operations should be performed to
ensure the data persistence.

This boolean option 'pmem' allows users to specify whether the backend
storage of memory-backend-file is a real persistent memory. If
'pmem=on', QEMU will set the flag RAM_PMEM in the RAM block of the
corresponding memory region. If 'pmem' is set while lack of libpmem
support, a error is generated.

Signed-off-by: Junyan He <junyan.he@intel.com>
Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-08-10 13:29:39 +03:00
Junyan He
cbfc017103 memory, exec: switch file ram allocation functions to 'flags' parameters
As more flag parameters besides the existing 'share' are going to be
added to following functions
memory_region_init_ram_from_file
qemu_ram_alloc_from_fd
qemu_ram_alloc_from_file
let's switch them to use the 'flags' parameters so as to ease future
flag additions.

The existing 'share' flag is converted to the RAM_SHARED bit in ram_flags,
and other flag bits are ignored by above functions right now.

Signed-off-by: Junyan He <junyan.he@intel.com>
Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2018-08-10 13:29:39 +03:00
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