From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751117AbeEUFkg (ORCPT ); Mon, 21 May 2018 01:40:36 -0400 Received: from mail-lf0-f68.google.com ([209.85.215.68]:40662 "EHLO mail-lf0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751072AbeEUFkf (ORCPT ); Mon, 21 May 2018 01:40:35 -0400 X-Google-Smtp-Source: AB8JxZr7/AQr/A7SWx8WTDHHEnE9EYP+LrWqdT4o+EouSk9z+/JgamigRWw1wmI6Pa0ObyCZDvK+IA== Subject: Re: [Xen-devel] [RFC 1/3] xen/balloon: Allow allocating DMA buffers To: Boris Ostrovsky , xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-media@vger.kernel.org, jgross@suse.com, konrad.wilk@oracle.com Cc: daniel.vetter@intel.com, matthew.d.roper@intel.com, dongwon.kim@intel.com, Oleksandr Andrushchenko References: <20180517082604.14828-1-andr2000@gmail.com> <20180517082604.14828-2-andr2000@gmail.com> <6a108876-19b7-49d0-3de2-9e10f984736c@oracle.com> From: Oleksandr Andrushchenko Message-ID: <9541926e-001a-e41e-317c-dbff6d687761@gmail.com> Date: Mon, 21 May 2018 08:40:30 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <6a108876-19b7-49d0-3de2-9e10f984736c@oracle.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/19/2018 01:04 AM, Boris Ostrovsky wrote: > On 05/17/2018 04:26 AM, Oleksandr Andrushchenko wrote: >> From: Oleksandr Andrushchenko > > A commit message would be useful. Sure, v1 will have it > >> Signed-off-by: Oleksandr Andrushchenko >> >> for (i = 0; i < nr_pages; i++) { >> - page = alloc_page(gfp); >> - if (page == NULL) { >> - nr_pages = i; >> - state = BP_EAGAIN; >> - break; >> + if (ext_pages) { >> + page = ext_pages[i]; >> + } else { >> + page = alloc_page(gfp); >> + if (page == NULL) { >> + nr_pages = i; >> + state = BP_EAGAIN; >> + break; >> + } >> } >> scrub_page(page); >> list_add(&page->lru, &pages); >> @@ -529,7 +565,7 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp) >> i = 0; >> list_for_each_entry_safe(page, tmp, &pages, lru) { >> /* XENMEM_decrease_reservation requires a GFN */ >> - frame_list[i++] = xen_page_to_gfn(page); >> + frames[i++] = xen_page_to_gfn(page); >> >> #ifdef CONFIG_XEN_HAVE_PVMMU >> /* >> @@ -552,18 +588,22 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp) >> #endif >> list_del(&page->lru); >> >> - balloon_append(page); >> + if (!ext_pages) >> + balloon_append(page); > > So what you are proposing is not really ballooning. You are just > piggybacking on existing interfaces, aren't you? Sort of. Basically I need to {increase|decrease}_reservation, not actually allocating ballooned pages. Do you think I can simply EXPORT_SYMBOL for {increase|decrease}_reservation? Any other suggestion? > -boris > > Thank you, Oleksandr From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oleksandr Andrushchenko Subject: Re: [Xen-devel] [RFC 1/3] xen/balloon: Allow allocating DMA buffers Date: Mon, 21 May 2018 08:40:30 +0300 Message-ID: <9541926e-001a-e41e-317c-dbff6d687761@gmail.com> References: <20180517082604.14828-1-andr2000@gmail.com> <20180517082604.14828-2-andr2000@gmail.com> <6a108876-19b7-49d0-3de2-9e10f984736c@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; Format="flowed" Content-Transfer-Encoding: base64 Return-path: Received: from mail-lf0-x244.google.com (mail-lf0-x244.google.com [IPv6:2a00:1450:4010:c07::244]) by gabe.freedesktop.org (Postfix) with ESMTPS id 42BD06E1EA for ; Mon, 21 May 2018 05:40:35 +0000 (UTC) Received: by mail-lf0-x244.google.com with SMTP id z142-v6so22069713lff.5 for ; Sun, 20 May 2018 22:40:34 -0700 (PDT) In-Reply-To: <6a108876-19b7-49d0-3de2-9e10f984736c@oracle.com> Content-Language: en-US List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Boris Ostrovsky , xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-media@vger.kernel.org, jgross@suse.com, konrad.wilk@oracle.com Cc: daniel.vetter@intel.com, dongwon.kim@intel.com, Oleksandr Andrushchenko List-Id: dri-devel@lists.freedesktop.org T24gMDUvMTkvMjAxOCAwMTowNCBBTSwgQm9yaXMgT3N0cm92c2t5IHdyb3RlOgo+IE9uIDA1LzE3 LzIwMTggMDQ6MjYgQU0sIE9sZWtzYW5kciBBbmRydXNoY2hlbmtvIHdyb3RlOgo+PiBGcm9tOiBP bGVrc2FuZHIgQW5kcnVzaGNoZW5rbyA8b2xla3NhbmRyX2FuZHJ1c2hjaGVua29AZXBhbS5jb20+ Cj4KPiBBIGNvbW1pdCBtZXNzYWdlIHdvdWxkIGJlIHVzZWZ1bC4KU3VyZSwgdjEgd2lsbCBoYXZl IGl0Cj4KPj4gU2lnbmVkLW9mZi1ieTogT2xla3NhbmRyIEFuZHJ1c2hjaGVua28gPG9sZWtzYW5k cl9hbmRydXNoY2hlbmtvQGVwYW0uY29tPgo+Pgo+PiAgIAlmb3IgKGkgPSAwOyBpIDwgbnJfcGFn ZXM7IGkrKykgewo+PiAtCQlwYWdlID0gYWxsb2NfcGFnZShnZnApOwo+PiAtCQlpZiAocGFnZSA9 PSBOVUxMKSB7Cj4+IC0JCQlucl9wYWdlcyA9IGk7Cj4+IC0JCQlzdGF0ZSA9IEJQX0VBR0FJTjsK Pj4gLQkJCWJyZWFrOwo+PiArCQlpZiAoZXh0X3BhZ2VzKSB7Cj4+ICsJCQlwYWdlID0gZXh0X3Bh Z2VzW2ldOwo+PiArCQl9IGVsc2Ugewo+PiArCQkJcGFnZSA9IGFsbG9jX3BhZ2UoZ2ZwKTsKPj4g KwkJCWlmIChwYWdlID09IE5VTEwpIHsKPj4gKwkJCQlucl9wYWdlcyA9IGk7Cj4+ICsJCQkJc3Rh dGUgPSBCUF9FQUdBSU47Cj4+ICsJCQkJYnJlYWs7Cj4+ICsJCQl9Cj4+ICAgCQl9Cj4+ICAgCQlz Y3J1Yl9wYWdlKHBhZ2UpOwo+PiAgIAkJbGlzdF9hZGQoJnBhZ2UtPmxydSwgJnBhZ2VzKTsKPj4g QEAgLTUyOSw3ICs1NjUsNyBAQCBzdGF0aWMgZW51bSBicF9zdGF0ZSBkZWNyZWFzZV9yZXNlcnZh dGlvbih1bnNpZ25lZCBsb25nIG5yX3BhZ2VzLCBnZnBfdCBnZnApCj4+ICAgCWkgPSAwOwo+PiAg IAlsaXN0X2Zvcl9lYWNoX2VudHJ5X3NhZmUocGFnZSwgdG1wLCAmcGFnZXMsIGxydSkgewo+PiAg IAkJLyogWEVOTUVNX2RlY3JlYXNlX3Jlc2VydmF0aW9uIHJlcXVpcmVzIGEgR0ZOICovCj4+IC0J CWZyYW1lX2xpc3RbaSsrXSA9IHhlbl9wYWdlX3RvX2dmbihwYWdlKTsKPj4gKwkJZnJhbWVzW2kr K10gPSB4ZW5fcGFnZV90b19nZm4ocGFnZSk7Cj4+ICAgCj4+ICAgI2lmZGVmIENPTkZJR19YRU5f SEFWRV9QVk1NVQo+PiAgIAkJLyoKPj4gQEAgLTU1MiwxOCArNTg4LDIyIEBAIHN0YXRpYyBlbnVt IGJwX3N0YXRlIGRlY3JlYXNlX3Jlc2VydmF0aW9uKHVuc2lnbmVkIGxvbmcgbnJfcGFnZXMsIGdm cF90IGdmcCkKPj4gICAjZW5kaWYKPj4gICAJCWxpc3RfZGVsKCZwYWdlLT5scnUpOwo+PiAgIAo+ PiAtCQliYWxsb29uX2FwcGVuZChwYWdlKTsKPj4gKwkJaWYgKCFleHRfcGFnZXMpCj4+ICsJCQli YWxsb29uX2FwcGVuZChwYWdlKTsKPgo+IFNvIHdoYXQgeW91IGFyZSBwcm9wb3NpbmcgaXMgbm90 IHJlYWxseSBiYWxsb29uaW5nLiBZb3UgYXJlIGp1c3QKPiBwaWdneWJhY2tpbmcgb24gZXhpc3Rp bmcgaW50ZXJmYWNlcywgYXJlbid0IHlvdT8KU29ydCBvZi4gQmFzaWNhbGx5IEkgbmVlZCB0byB7 aW5jcmVhc2V8ZGVjcmVhc2V9X3Jlc2VydmF0aW9uLCBub3QgYWN0dWFsbHkKYWxsb2NhdGluZyBi YWxsb29uZWQgcGFnZXMuCkRvIHlvdSB0aGluayBJIGNhbiBzaW1wbHkgRVhQT1JUX1NZTUJPTCBm b3Ige2luY3JlYXNlfGRlY3JlYXNlfV9yZXNlcnZhdGlvbj8KQW55IG90aGVyIHN1Z2dlc3Rpb24/ Cj4gLWJvcmlzCj4KPgpUaGFuayB5b3UsCk9sZWtzYW5kcgpfX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fXwpkcmktZGV2ZWwgbWFpbGluZyBsaXN0CmRyaS1kZXZl bEBsaXN0cy5mcmVlZGVza3RvcC5vcmcKaHR0cHM6Ly9saXN0cy5mcmVlZGVza3RvcC5vcmcvbWFp bG1hbi9saXN0aW5mby9kcmktZGV2ZWwK