qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Wei Yang <richardw.yang@linux.intel.com>
To: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Wei Yang <richardw.yang@linux.intel.com>,
	qemu-devel@nongnu.org, xiaoguangrong.eric@gmail.com,
	pbonzini@redhat.com, pagupta@redhat.com,
	yu.c.zhang@linux.intel.com, mst@redhat.com, ehabkost@redhat.com,
	imammedo@redhat.com, dan.j.williams@intel.com,
	yi.z.zhang@linux.intel.com,
	Haozhong Zhang <haozhong.zhang@intel.com>
Subject: Re: [Qemu-devel] [PATCH v14 1/2] util/mmap-alloc: support MAP_SYNC in qemu_ram_mmap()
Date: Wed, 24 Apr 2019 09:01:05 +0800	[thread overview]
Message-ID: <20190424010105.GA12824@richard> (raw)
In-Reply-To: <20190423092518.GD32465@stefanha-x1.localdomain>

On Tue, Apr 23, 2019 at 10:25:18AM +0100, Stefan Hajnoczi wrote:
[...]
>> +#ifdef CONFIG_LINUX
>> +#include <linux/mman.h>
>> +#else  /* !CONFIG_LINUX */
>> +#define MAP_SYNC              0x0
>> +#define MAP_SHARED_VALIDATE   0x0
>> +#endif /* CONFIG_LINUX */
>
>MAP_SHARED_VALIDATE is is from 2017:
>
>  commit 1c9725974074a047f6080eecc62c50a8e840d050
>  Author: Dan Williams <dan.j.williams@intel.com>
>  Date:   Wed Nov 1 16:36:30 2017 +0100
>
>    mm: introduce MAP_SHARED_VALIDATE, a mechanism to safely define new mmap flags
>
>This code fails to compile on Linux hosts with pre-4.15 headers.
>

Ok, qemu build will fail on pre-4.15 linux.

>Instead you could use the following (even on Linux!):
>
>  #ifndef MAP_SYNC
>  #define MAP_SYNC 0
>  #endif
>  #ifndef MAP_SHARED_VALIDATE
>  #define MAP_SHARED_VALIDATE 0
>  #endif
>
>Either way:

You mean replace the above code to:

#ifdef CONFIG_LINUX
#include <linux/mman.h>
#endif /* CONFIG_LINUX */

#ifndef MAP_SYNC
#define MAP_SYNC 0
#endif
#ifndef MAP_SHARED_VALIDATE
#define MAP_SHARED_VALIDATE 0
#endif

>
>Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>



-- 
Wei Yang
Help you, Help me

WARNING: multiple messages have this Message-ID (diff)
From: Wei Yang <richardw.yang@linux.intel.com>
To: Stefan Hajnoczi <stefanha@redhat.com>
Cc: pagupta@redhat.com, xiaoguangrong.eric@gmail.com, mst@redhat.com,
	qemu-devel@nongnu.org, yi.z.zhang@linux.intel.com,
	yu.c.zhang@linux.intel.com,
	Wei Yang <richardw.yang@linux.intel.com>,
	Haozhong Zhang <haozhong.zhang@intel.com>,
	imammedo@redhat.com, pbonzini@redhat.com,
	dan.j.williams@intel.com, ehabkost@redhat.com
Subject: Re: [Qemu-devel] [PATCH v14 1/2] util/mmap-alloc: support MAP_SYNC in qemu_ram_mmap()
Date: Wed, 24 Apr 2019 09:01:05 +0800	[thread overview]
Message-ID: <20190424010105.GA12824@richard> (raw)
Message-ID: <20190424010105.HeG1_cHsnZz_O-h9laCMIqmnsaGrA9hLr6OBYDe8AEA@z> (raw)
In-Reply-To: <20190423092518.GD32465@stefanha-x1.localdomain>

On Tue, Apr 23, 2019 at 10:25:18AM +0100, Stefan Hajnoczi wrote:
[...]
>> +#ifdef CONFIG_LINUX
>> +#include <linux/mman.h>
>> +#else  /* !CONFIG_LINUX */
>> +#define MAP_SYNC              0x0
>> +#define MAP_SHARED_VALIDATE   0x0
>> +#endif /* CONFIG_LINUX */
>
>MAP_SHARED_VALIDATE is is from 2017:
>
>  commit 1c9725974074a047f6080eecc62c50a8e840d050
>  Author: Dan Williams <dan.j.williams@intel.com>
>  Date:   Wed Nov 1 16:36:30 2017 +0100
>
>    mm: introduce MAP_SHARED_VALIDATE, a mechanism to safely define new mmap flags
>
>This code fails to compile on Linux hosts with pre-4.15 headers.
>

Ok, qemu build will fail on pre-4.15 linux.

>Instead you could use the following (even on Linux!):
>
>  #ifndef MAP_SYNC
>  #define MAP_SYNC 0
>  #endif
>  #ifndef MAP_SHARED_VALIDATE
>  #define MAP_SHARED_VALIDATE 0
>  #endif
>
>Either way:

You mean replace the above code to:

#ifdef CONFIG_LINUX
#include <linux/mman.h>
#endif /* CONFIG_LINUX */

#ifndef MAP_SYNC
#define MAP_SYNC 0
#endif
#ifndef MAP_SHARED_VALIDATE
#define MAP_SHARED_VALIDATE 0
#endif

>
>Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>



-- 
Wei Yang
Help you, Help me


  parent reply	other threads:[~2019-04-24  1:01 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-04-22  0:48 [Qemu-devel] [PATCH v14 0/2] support MAP_SYNC for memory-backend-file Wei Yang
2019-04-22  0:48 ` Wei Yang
2019-04-22  0:48 ` [Qemu-devel] [PATCH v14 1/2] util/mmap-alloc: support MAP_SYNC in qemu_ram_mmap() Wei Yang
2019-04-22  0:48   ` Wei Yang
2019-04-23  9:25   ` Stefan Hajnoczi
2019-04-23  9:25     ` Stefan Hajnoczi
2019-04-24  1:01     ` Wei Yang [this message]
2019-04-24  1:01       ` Wei Yang
2019-04-25  8:26       ` Stefan Hajnoczi
2019-04-25  8:26         ` Stefan Hajnoczi
2019-04-22  0:48 ` [Qemu-devel] [PATCH v14 2/2] docs: Added MAP_SYNC documentation Wei Yang
2019-04-22  0:48   ` Wei Yang
2019-04-23  9:26   ` Stefan Hajnoczi
2019-04-23  9:26     ` Stefan Hajnoczi
2019-04-23  9:57   ` Pankaj Gupta
2019-04-23  9:57     ` Pankaj Gupta
2019-04-22 12:34 ` [Qemu-devel] [PATCH v14 0/2] support MAP_SYNC for memory-backend-file Michael S. Tsirkin
2019-04-22 12:34   ` Michael S. Tsirkin
2019-04-22 18:22   ` Eduardo Habkost
2019-04-22 18:22     ` Eduardo Habkost
2019-04-23  2:41     ` Wei Yang
2019-04-23  2:41       ` Wei Yang
2019-04-23 12:43     ` Michael S. Tsirkin
2019-04-23 12:43       ` Michael S. Tsirkin

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190424010105.GA12824@richard \
    --to=richardw.yang@linux.intel.com \
    --cc=dan.j.williams@intel.com \
    --cc=ehabkost@redhat.com \
    --cc=haozhong.zhang@intel.com \
    --cc=imammedo@redhat.com \
    --cc=mst@redhat.com \
    --cc=pagupta@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=qemu-devel@nongnu.org \
    --cc=stefanha@redhat.com \
    --cc=xiaoguangrong.eric@gmail.com \
    --cc=yi.z.zhang@linux.intel.com \
    --cc=yu.c.zhang@linux.intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).