From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl1-f198.google.com (mail-pl1-f198.google.com [209.85.214.198]) by kanga.kvack.org (Postfix) with ESMTP id D11006B0269 for ; Mon, 22 Oct 2018 16:18:49 -0400 (EDT) Received: by mail-pl1-f198.google.com with SMTP id v7-v6so31240097plo.23 for ; Mon, 22 Oct 2018 13:18:49 -0700 (PDT) Received: from mga05.intel.com (mga05.intel.com. [192.55.52.43]) by mx.google.com with ESMTPS id r15-v6si34776466pgh.88.2018.10.22.13.18.48 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 22 Oct 2018 13:18:48 -0700 (PDT) Subject: [PATCH 7/9] dax/kmem: actually perform memory hotplug From: Dave Hansen Date: Mon, 22 Oct 2018 13:13:29 -0700 References: <20181022201317.8558C1D8@viggo.jf.intel.com> In-Reply-To: <20181022201317.8558C1D8@viggo.jf.intel.com> Message-Id: <20181022201329.518577A4@viggo.jf.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: linux-kernel@vger.kernel.org Cc: Dave Hansen , dan.j.williams@intel.com, dave.jiang@intel.com, zwisler@kernel.org, vishal.l.verma@intel.com, thomas.lendacky@amd.com, akpm@linux-foundation.org, mhocko@suse.com, linux-nvdimm@lists.01.org, linux-mm@kvack.org, ying.huang@intel.com, fengguang.wu@intel.com This is the meat of this whole series. When the "kmem" device's probe function is called and we know we have a good persistent memory device, hotplug the memory back into the main kernel. Cc: Dan Williams Cc: Dave Jiang Cc: Ross Zwisler Cc: Vishal Verma Cc: Tom Lendacky Cc: Andrew Morton Cc: Michal Hocko Cc: linux-nvdimm@lists.01.org Cc: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org Cc: Huang Ying Cc: Fengguang Wu --- b/drivers/dax/kmem.c | 28 +++++++++++++++++++++++++--- 1 file changed, 25 insertions(+), 3 deletions(-) diff -puN drivers/dax/kmem.c~dax-kmem-hotplug drivers/dax/kmem.c --- a/drivers/dax/kmem.c~dax-kmem-hotplug 2018-10-22 13:12:24.069930387 -0700 +++ b/drivers/dax/kmem.c 2018-10-22 13:12:24.072930387 -0700 @@ -55,10 +55,12 @@ static void dax_kmem_percpu_kill(void *d static int dax_kmem_probe(struct device *dev) { void *addr; + int numa_node; struct resource res; int rc, id, region_id; struct nd_pfn_sb *pfn_sb; struct dev_dax *dev_dax; + struct resource *new_res; struct dax_kmem *dax_kmem; struct nd_namespace_io *nsio; struct dax_region *dax_region; @@ -86,13 +88,30 @@ static int dax_kmem_probe(struct device pfn_sb = nd_pfn->pfn_sb; - if (!devm_request_mem_region(dev, nsio->res.start, - resource_size(&nsio->res), - dev_name(&ndns->dev))) { + new_res = devm_request_mem_region(dev, nsio->res.start, + resource_size(&nsio->res), + "System RAM (pmem)"); + if (!new_res) { dev_warn(dev, "could not reserve region %pR\n", &nsio->res); return -EBUSY; } + /* + * Set flags appropriate for System RAM. Leave ..._BUSY clear + * so that add_memory() can add a child resource. + */ + new_res->flags = IORESOURCE_SYSTEM_RAM; + + numa_node = dev_to_node(dev); + if (numa_node < 0) { + pr_warn_once("bad numa_node: %d, forcing to 0\n", numa_node); + numa_node = 0; + } + + rc = add_memory(numa_node, nsio->res.start, resource_size(&nsio->res)); + if (rc) + return rc; + dax_kmem->dev = dev; init_completion(&dax_kmem->cmp); rc = percpu_ref_init(&dax_kmem->ref, dax_kmem_percpu_release, 0, @@ -106,6 +125,9 @@ static int dax_kmem_probe(struct device return rc; dax_kmem->pgmap.ref = &dax_kmem->ref; + + dax_kmem->pgmap.res.name = "name_kmem_override2"; + addr = devm_memremap_pages(dev, &dax_kmem->pgmap); if (IS_ERR(addr)) return PTR_ERR(addr); _