From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [PATCH] vmalloc: introduce vmap_pfn for persistent memory Date: Wed, 8 Nov 2017 01:59:09 -0800 Message-ID: <20171108095909.GA7390@infradead.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org To: Mikulas Patocka Cc: Ross Zwisler , linux-mm@kvack.org, linux-nvdimm@lists.01.org, Dan Williams , dm-devel@redhat.com, Laura Abbott , Christoph Hellwig , "Kirill A . Shutemov" List-Id: dm-devel.ids On Tue, Nov 07, 2017 at 05:03:11PM -0500, Mikulas Patocka wrote: > Hi > > I am developing a driver that uses persistent memory for caching. A > persistent memory device can be mapped in several discontiguous ranges. > > The kernel has a function vmap that takes an array of pointers to pages > and maps these pages to contiguous linear address space. However, it can't > be used on persistent memory because persistent memory may not be backed > by page structures. > > This patch introduces a new function vmap_pfn, it works like vmap, but > takes an array of pfn_t - so it can be used on persistent memory. How is cache flushing going to work for this interface assuming that your write to/from the virtual address and expect it to be persisted on pmem? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 48F4620355214 for ; Wed, 8 Nov 2017 01:55:10 -0800 (PST) Date: Wed, 8 Nov 2017 01:59:09 -0800 From: Christoph Hellwig Subject: Re: [PATCH] vmalloc: introduce vmap_pfn for persistent memory Message-ID: <20171108095909.GA7390@infradead.org> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" To: Mikulas Patocka Cc: linux-nvdimm@lists.01.org, Christoph Hellwig , linux-mm@kvack.org, dm-devel@redhat.com, Laura Abbott , "Kirill A . Shutemov" List-ID: On Tue, Nov 07, 2017 at 05:03:11PM -0500, Mikulas Patocka wrote: > Hi > > I am developing a driver that uses persistent memory for caching. A > persistent memory device can be mapped in several discontiguous ranges. > > The kernel has a function vmap that takes an array of pointers to pages > and maps these pages to contiguous linear address space. However, it can't > be used on persistent memory because persistent memory may not be backed > by page structures. > > This patch introduces a new function vmap_pfn, it works like vmap, but > takes an array of pfn_t - so it can be used on persistent memory. How is cache flushing going to work for this interface assuming that your write to/from the virtual address and expect it to be persisted on pmem? _______________________________________________ Linux-nvdimm mailing list Linux-nvdimm@lists.01.org https://lists.01.org/mailman/listinfo/linux-nvdimm