From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga02.intel.com ([134.134.136.20]:3834 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750852AbcEHSmv (ORCPT ); Sun, 8 May 2016 14:42:51 -0400 From: "Verma, Vishal L" To: "hch@infradead.org" CC: "linux-kernel@vger.kernel.org" , "linux-block@vger.kernel.org" , "xfs@oss.sgi.com" , "linux-nvdimm@ml01.01.org" , "linux-mm@kvack.org" , "viro@zeniv.linux.org.uk" , "Williams, Dan J" , "axboe@fb.com" , "akpm@linux-foundation.org" , "linux-fsdevel@vger.kernel.org" , "linux-ext4@vger.kernel.org" , "david@fromorbit.com" , "jack@suse.cz" , "matthew@wil.cx" Subject: Re: [PATCH v4 5/7] fs: prioritize and separate direct_io from dax_io Date: Sun, 8 May 2016 18:42:37 +0000 Message-ID: <1462732956.3006.4.camel@intel.com> References: <1461878218-3844-1-git-send-email-vishal.l.verma@intel.com> <1461878218-3844-6-git-send-email-vishal.l.verma@intel.com> <5727753F.6090104@plexistor.com> <20160505142433.GA4557@infradead.org> <20160505152230.GA3994@infradead.org> <1462484695.29294.7.camel@intel.com> <20160508090115.GE15458@infradead.org> In-Reply-To: <20160508090115.GE15458@infradead.org> Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Sender: linux-block-owner@vger.kernel.org List-Id: linux-block@vger.kernel.org T24gU3VuLCAyMDE2LTA1LTA4IGF0IDAyOjAxIC0wNzAwLCBoY2hAaW5mcmFkZWFkLm9yZyB3cm90 ZToNCj4gT24gVGh1LCBNYXkgMDUsIDIwMTYgYXQgMDk6NDU6MDdQTSArMDAwMCwgVmVybWEsIFZp c2hhbCBMIHdyb3RlOg0KPiA+IA0KPiA+IEknbSBub3Qgc3VyZSBJIGNvbXBsZXRlbHkgdW5kZXJz dGFuZCBob3cgdGhpcyB3aWxsIHdvcms/IENhbiB5b3UNCj4gPiBleHBsYWluDQo+ID4gYSBiaXQ/ IFdvdWxkIHdlIGhhdmUgdG8gZXhwb3J0IHJ3X2J5dGVzIHVwIHRvIGxheWVycyBhYm92ZSB0aGUg cG1lbQ0KPiA+IGRyaXZlcj8gV2hlcmUgZG9lcyBnZXRfdXNlcl9wYWdlcyBjb21lIGluPw0KPiBB IERBWCBmaWxlc3lzdGVtIGNhbiBkaXJlY3RseSB1c2UgdGhlIG52ZGltbSBsYXllciB0aGUgc2Ft ZSB3YXkgYnR0DQo+IGRvZSxzIHdoYXQncyB0aGUgcHJvYmxlbT8NCg0KVGhlIEJUVCBkb2VzIHJ3 X2J5dGVzIHRocm91Z2ggYW4gaW50ZXJuYWwtdG8tbGlibnZkaW1tIG1lY2hhbmlzbSwgYnV0DQpy d19ieXRlcyBpc24ndCBleHBvcnRlZCB0byB0aGUgZmlsZXN5c3RlbSwgY3VycmVudGx5Li4gVG8g ZG8gdGhpcyB3ZSdkDQpoYXZlIHRvIGVpdGhlciBhZGQgYW4gcndfYnl0ZXMgdG8gYmxvY2sgZGV2 aWNlIG9wZXJhdGlvbnMuLi5vcg0Kc29tZXRoaW5nLg0KDQpBbm90aGVyIHRoaW5nIGlzIHJ3X2J5 dGVzIGN1cnJlbnRseSBkb2Vzbid0IGRvIGVycm9yIGNsZWFyaW5nIGVpdGhlci4NCldlIHN0b3Jl IGJhZGJsb2NrcyBhdCBzZWN0b3IgZ3JhbnVsYXJpdHksIGFuZCBsaWtlIERhbiBzYWlkIGVhcmxp ZXIsDQp0aGF0IGhpZGVzIHRoZSBjbGVhcl9lcnJvciBhbGlnbm1lbnQgcmVxdWlyZW1lbnRzIGFu ZCB1cHBlciBsYXllcnMNCmRvbid0IGhhdmUgdG8gYmUgYXdhcmUgb2YgaXQuIFRvIG1ha2Ugcndf Ynl0ZXMgY2xlYXIgc3ViLXNlY3RvciBlcnJvcnMsDQp3ZSdkIGhhdmUgdG8gY2hhbmdlIHRoZSBn cmFudWxhcml0eSBvZiBiYWQtYmxvY2tzLCBhbmQgbWFrZSB1cHBlcg0KbGF5ZXJzIGF3YXJlIG9m IHRoZSBjbGVhcmluZyBhbGlnbm1lbnQgcmVxdWlyZW1lbnRzLg0KDQpVc2luZyBhIGJsb2NrLXdy aXRlIHNlbWFudGljIGZvciBjbGVhcmluZyBoaWRlcyBhbGwgdGhpcyBhd2F5Lg0KDQo+IA0KPiBS ZSBnZXRfdXNlcl9wYWdlcyBteSBpZGVhIHdhcyB0byBzaW1wbHkgdXNlIHRoYXQgdG8gbG9jayBk b3duIHRoZQ0KPiB1c2VyDQo+IHBhZ2VzIHNvIHRoYXQgd2UgY2FuIGNhbGwgcndfYnl0ZXMgb24g aXQuwqDCoEhvdyBlbHNlIHdvdWxkIHlvdSBkbw0KPiBpdD/CoMKgRG8NCj4gYSBrbWFsbG9jLCBj b3B5X2Zyb21fdXNlciBhbmQgdGhlbiBhbm90aGVyIG1lbWNweT8= From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Verma, Vishal L" Subject: Re: [PATCH v4 5/7] fs: prioritize and separate direct_io from dax_io Date: Sun, 8 May 2016 18:42:37 +0000 Message-ID: <1462732956.3006.4.camel@intel.com> References: <1461878218-3844-1-git-send-email-vishal.l.verma@intel.com> <1461878218-3844-6-git-send-email-vishal.l.verma@intel.com> <5727753F.6090104@plexistor.com> <20160505142433.GA4557@infradead.org> <20160505152230.GA3994@infradead.org> <1462484695.29294.7.camel@intel.com> <20160508090115.GE15458@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Cc: "linux-kernel@vger.kernel.org" , "linux-block@vger.kernel.org" , "xfs@oss.sgi.com" , "linux-nvdimm@ml01.01.org" , "linux-mm@kvack.org" , "viro@zeniv.linux.org.uk" , "Williams, Dan J" , "axboe@fb.com" , "akpm@linux-foundation.org" , "linux-fsdevel@vger.kernel.org" , "linux-ext4@vger.kernel.org" , "david@fromorbit.com" , "jack@suse.cz" , "matthew@wil.cx" To: "hch@infradead.org" Return-path: In-Reply-To: <20160508090115.GE15458@infradead.org> Content-Language: en-US Content-ID: Sender: owner-linux-mm@kvack.org List-Id: linux-ext4.vger.kernel.org T24gU3VuLCAyMDE2LTA1LTA4IGF0IDAyOjAxIC0wNzAwLCBoY2hAaW5mcmFkZWFkLm9yZyB3cm90 ZToNCj4gT24gVGh1LCBNYXkgMDUsIDIwMTYgYXQgMDk6NDU6MDdQTSArMDAwMCwgVmVybWEsIFZp c2hhbCBMIHdyb3RlOg0KPiA+IA0KPiA+IEknbSBub3Qgc3VyZSBJIGNvbXBsZXRlbHkgdW5kZXJz dGFuZCBob3cgdGhpcyB3aWxsIHdvcms/IENhbiB5b3UNCj4gPiBleHBsYWluDQo+ID4gYSBiaXQ/ IFdvdWxkIHdlIGhhdmUgdG8gZXhwb3J0IHJ3X2J5dGVzIHVwIHRvIGxheWVycyBhYm92ZSB0aGUg cG1lbQ0KPiA+IGRyaXZlcj8gV2hlcmUgZG9lcyBnZXRfdXNlcl9wYWdlcyBjb21lIGluPw0KPiBB IERBWCBmaWxlc3lzdGVtIGNhbiBkaXJlY3RseSB1c2UgdGhlIG52ZGltbSBsYXllciB0aGUgc2Ft ZSB3YXkgYnR0DQo+IGRvZSxzIHdoYXQncyB0aGUgcHJvYmxlbT8NCg0KVGhlIEJUVCBkb2VzIHJ3 X2J5dGVzIHRocm91Z2ggYW4gaW50ZXJuYWwtdG8tbGlibnZkaW1tIG1lY2hhbmlzbSwgYnV0DQpy d19ieXRlcyBpc24ndCBleHBvcnRlZCB0byB0aGUgZmlsZXN5c3RlbSwgY3VycmVudGx5Li4gVG8g ZG8gdGhpcyB3ZSdkDQpoYXZlIHRvIGVpdGhlciBhZGQgYW4gcndfYnl0ZXMgdG8gYmxvY2sgZGV2 aWNlIG9wZXJhdGlvbnMuLi5vcg0Kc29tZXRoaW5nLg0KDQpBbm90aGVyIHRoaW5nIGlzIHJ3X2J5 dGVzIGN1cnJlbnRseSBkb2Vzbid0IGRvIGVycm9yIGNsZWFyaW5nIGVpdGhlci4NCldlIHN0b3Jl IGJhZGJsb2NrcyBhdCBzZWN0b3IgZ3JhbnVsYXJpdHksIGFuZCBsaWtlIERhbiBzYWlkIGVhcmxp ZXIsDQp0aGF0IGhpZGVzIHRoZSBjbGVhcl9lcnJvciBhbGlnbm1lbnQgcmVxdWlyZW1lbnRzIGFu ZCB1cHBlciBsYXllcnMNCmRvbid0IGhhdmUgdG8gYmUgYXdhcmUgb2YgaXQuIFRvIG1ha2Ugcndf Ynl0ZXMgY2xlYXIgc3ViLXNlY3RvciBlcnJvcnMsDQp3ZSdkIGhhdmUgdG8gY2hhbmdlIHRoZSBn cmFudWxhcml0eSBvZiBiYWQtYmxvY2tzLCBhbmQgbWFrZSB1cHBlcg0KbGF5ZXJzIGF3YXJlIG9m IHRoZSBjbGVhcmluZyBhbGlnbm1lbnQgcmVxdWlyZW1lbnRzLg0KDQpVc2luZyBhIGJsb2NrLXdy aXRlIHNlbWFudGljIGZvciBjbGVhcmluZyBoaWRlcyBhbGwgdGhpcyBhd2F5Lg0KDQo+IA0KPiBS ZSBnZXRfdXNlcl9wYWdlcyBteSBpZGVhIHdhcyB0byBzaW1wbHkgdXNlIHRoYXQgdG8gbG9jayBk b3duIHRoZQ0KPiB1c2VyDQo+IHBhZ2VzIHNvIHRoYXQgd2UgY2FuIGNhbGwgcndfYnl0ZXMgb24g aXQuwqDCoEhvdyBlbHNlIHdvdWxkIHlvdSBkbw0KPiBpdD/CoMKgRG8NCj4gYSBrbWFsbG9jLCBj b3B5X2Zyb21fdXNlciBhbmQgdGhlbiBhbm90aGVyIG1lbWNweT8= -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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Don't email: email@kvack.org From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay1.corp.sgi.com [137.38.102.111]) by oss.sgi.com (Postfix) with ESMTP id 732847CA4 for ; Sun, 8 May 2016 13:42:44 -0500 (CDT) Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by relay1.corp.sgi.com (Postfix) with ESMTP id 45ACD8F8033 for ; Sun, 8 May 2016 11:42:41 -0700 (PDT) Received: from mga01.intel.com ([192.55.52.88]) by cuda.sgi.com with ESMTP id DTWjf3pW9hQw2FMg for ; Sun, 08 May 2016 11:42:40 -0700 (PDT) From: "Verma, Vishal L" Subject: Re: [PATCH v4 5/7] fs: prioritize and separate direct_io from dax_io Date: Sun, 8 May 2016 18:42:37 +0000 Message-ID: <1462732956.3006.4.camel@intel.com> References: <1461878218-3844-1-git-send-email-vishal.l.verma@intel.com> <1461878218-3844-6-git-send-email-vishal.l.verma@intel.com> <5727753F.6090104@plexistor.com> <20160505142433.GA4557@infradead.org> <20160505152230.GA3994@infradead.org> <1462484695.29294.7.camel@intel.com> <20160508090115.GE15458@infradead.org> In-Reply-To: <20160508090115.GE15458@infradead.org> Content-Language: en-US Content-ID: MIME-Version: 1.0 List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: "hch@infradead.org" Cc: "axboe@fb.com" , "jack@suse.cz" , "matthew@wil.cx" , "linux-nvdimm@ml01.01.org" , "linux-kernel@vger.kernel.org" , "xfs@oss.sgi.com" , "linux-block@vger.kernel.org" , "linux-mm@kvack.org" , "viro@zeniv.linux.org.uk" , "linux-fsdevel@vger.kernel.org" , "Williams, Dan J" , "linux-ext4@vger.kernel.org" , "akpm@linux-foundation.org" T24gU3VuLCAyMDE2LTA1LTA4IGF0IDAyOjAxIC0wNzAwLCBoY2hAaW5mcmFkZWFkLm9yZyB3cm90 ZToNCj4gT24gVGh1LCBNYXkgMDUsIDIwMTYgYXQgMDk6NDU6MDdQTSArMDAwMCwgVmVybWEsIFZp c2hhbCBMIHdyb3RlOg0KPiA+IA0KPiA+IEknbSBub3Qgc3VyZSBJIGNvbXBsZXRlbHkgdW5kZXJz dGFuZCBob3cgdGhpcyB3aWxsIHdvcms/IENhbiB5b3UNCj4gPiBleHBsYWluDQo+ID4gYSBiaXQ/ IFdvdWxkIHdlIGhhdmUgdG8gZXhwb3J0IHJ3X2J5dGVzIHVwIHRvIGxheWVycyBhYm92ZSB0aGUg cG1lbQ0KPiA+IGRyaXZlcj8gV2hlcmUgZG9lcyBnZXRfdXNlcl9wYWdlcyBjb21lIGluPw0KPiBB IERBWCBmaWxlc3lzdGVtIGNhbiBkaXJlY3RseSB1c2UgdGhlIG52ZGltbSBsYXllciB0aGUgc2Ft ZSB3YXkgYnR0DQo+IGRvZSxzIHdoYXQncyB0aGUgcHJvYmxlbT8NCg0KVGhlIEJUVCBkb2VzIHJ3 X2J5dGVzIHRocm91Z2ggYW4gaW50ZXJuYWwtdG8tbGlibnZkaW1tIG1lY2hhbmlzbSwgYnV0DQpy d19ieXRlcyBpc24ndCBleHBvcnRlZCB0byB0aGUgZmlsZXN5c3RlbSwgY3VycmVudGx5Li4gVG8g ZG8gdGhpcyB3ZSdkDQpoYXZlIHRvIGVpdGhlciBhZGQgYW4gcndfYnl0ZXMgdG8gYmxvY2sgZGV2 aWNlIG9wZXJhdGlvbnMuLi5vcg0Kc29tZXRoaW5nLg0KDQpBbm90aGVyIHRoaW5nIGlzIHJ3X2J5 dGVzIGN1cnJlbnRseSBkb2Vzbid0IGRvIGVycm9yIGNsZWFyaW5nIGVpdGhlci4NCldlIHN0b3Jl IGJhZGJsb2NrcyBhdCBzZWN0b3IgZ3JhbnVsYXJpdHksIGFuZCBsaWtlIERhbiBzYWlkIGVhcmxp ZXIsDQp0aGF0IGhpZGVzIHRoZSBjbGVhcl9lcnJvciBhbGlnbm1lbnQgcmVxdWlyZW1lbnRzIGFu ZCB1cHBlciBsYXllcnMNCmRvbid0IGhhdmUgdG8gYmUgYXdhcmUgb2YgaXQuIFRvIG1ha2Ugcndf Ynl0ZXMgY2xlYXIgc3ViLXNlY3RvciBlcnJvcnMsDQp3ZSdkIGhhdmUgdG8gY2hhbmdlIHRoZSBn cmFudWxhcml0eSBvZiBiYWQtYmxvY2tzLCBhbmQgbWFrZSB1cHBlcg0KbGF5ZXJzIGF3YXJlIG9m IHRoZSBjbGVhcmluZyBhbGlnbm1lbnQgcmVxdWlyZW1lbnRzLg0KDQpVc2luZyBhIGJsb2NrLXdy aXRlIHNlbWFudGljIGZvciBjbGVhcmluZyBoaWRlcyBhbGwgdGhpcyBhd2F5Lg0KDQo+IA0KPiBS ZSBnZXRfdXNlcl9wYWdlcyBteSBpZGVhIHdhcyB0byBzaW1wbHkgdXNlIHRoYXQgdG8gbG9jayBk b3duIHRoZQ0KPiB1c2VyDQo+IHBhZ2VzIHNvIHRoYXQgd2UgY2FuIGNhbGwgcndfYnl0ZXMgb24g aXQuwqDCoEhvdyBlbHNlIHdvdWxkIHlvdSBkbw0KPiBpdD/CoMKgRG8NCj4gYSBrbWFsbG9jLCBj b3B5X2Zyb21fdXNlciBhbmQgdGhlbiBhbm90aGVyIG1lbWNweT8KX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX18KeGZzIG1haWxpbmcgbGlzdAp4ZnNAb3NzLnNn aS5jb20KaHR0cDovL29zcy5zZ2kuY29tL21haWxtYW4vbGlzdGluZm8veGZzCg== From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750972AbcEHSmx (ORCPT ); Sun, 8 May 2016 14:42:53 -0400 Received: from mga02.intel.com ([134.134.136.20]:3834 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750852AbcEHSmv (ORCPT ); Sun, 8 May 2016 14:42:51 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.24,597,1455004800"; d="scan'208";a="801781273" From: "Verma, Vishal L" To: "hch@infradead.org" CC: "linux-kernel@vger.kernel.org" , "linux-block@vger.kernel.org" , "xfs@oss.sgi.com" , "linux-nvdimm@ml01.01.org" , "linux-mm@kvack.org" , "viro@zeniv.linux.org.uk" , "Williams, Dan J" , "axboe@fb.com" , "akpm@linux-foundation.org" , "linux-fsdevel@vger.kernel.org" , "linux-ext4@vger.kernel.org" , "david@fromorbit.com" , "jack@suse.cz" , "matthew@wil.cx" Subject: Re: [PATCH v4 5/7] fs: prioritize and separate direct_io from dax_io Thread-Topic: [PATCH v4 5/7] fs: prioritize and separate direct_io from dax_io Thread-Index: AQHRoZNfS9ZF3cQEEUydwj8b8xF2vZ+mRHyAgAShZYCAAA4/AIAAAfIAgABq2YCAA+GggIAAom4A Date: Sun, 8 May 2016 18:42:37 +0000 Message-ID: <1462732956.3006.4.camel@intel.com> References: <1461878218-3844-1-git-send-email-vishal.l.verma@intel.com> <1461878218-3844-6-git-send-email-vishal.l.verma@intel.com> <5727753F.6090104@plexistor.com> <20160505142433.GA4557@infradead.org> <20160505152230.GA3994@infradead.org> <1462484695.29294.7.camel@intel.com> <20160508090115.GE15458@infradead.org> In-Reply-To: <20160508090115.GE15458@infradead.org> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.255.73.102] Content-Type: text/plain; charset="utf-8" Content-ID: MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id u48IgugC030814 On Sun, 2016-05-08 at 02:01 -0700, hch@infradead.org wrote: > On Thu, May 05, 2016 at 09:45:07PM +0000, Verma, Vishal L wrote: > > > > I'm not sure I completely understand how this will work? Can you > > explain > > a bit? Would we have to export rw_bytes up to layers above the pmem > > driver? Where does get_user_pages come in? > A DAX filesystem can directly use the nvdimm layer the same way btt > doe,s what's the problem? The BTT does rw_bytes through an internal-to-libnvdimm mechanism, but rw_bytes isn't exported to the filesystem, currently.. To do this we'd have to either add an rw_bytes to block device operations...or something. Another thing is rw_bytes currently doesn't do error clearing either. We store badblocks at sector granularity, and like Dan said earlier, that hides the clear_error alignment requirements and upper layers don't have to be aware of it. To make rw_bytes clear sub-sector errors, we'd have to change the granularity of bad-blocks, and make upper layers aware of the clearing alignment requirements. Using a block-write semantic for clearing hides all this away. > > Re get_user_pages my idea was to simply use that to lock down the > user > pages so that we can call rw_bytes on it.  How else would you do > it?  Do > a kmalloc, copy_from_user and then another memcpy?