From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 762E8C48BDF for ; Fri, 18 Jun 2021 16:58:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 516B661248 for ; Fri, 18 Jun 2021 16:58:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232203AbhFRRAy (ORCPT ); Fri, 18 Jun 2021 13:00:54 -0400 Received: from mga11.intel.com ([192.55.52.93]:52680 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231601AbhFRRAx (ORCPT ); Fri, 18 Jun 2021 13:00:53 -0400 IronPort-SDR: 1VXIFNHiBsb7ybk6M2eJRVaOFwUPV7SYfIxQt8r4YYLem1MYgFgJt/8Hf3sjLfh3gGzjmQOiC7 yfVc9Zew5ckw== X-IronPort-AV: E=McAfee;i="6200,9189,10019"; a="203564641" X-IronPort-AV: E=Sophos;i="5.83,284,1616482800"; d="scan'208";a="203564641" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Jun 2021 09:58:37 -0700 IronPort-SDR: +LIj31sOxq8AneMpLOqILkUR0jH0JQ09sTbq4TIibEFSKdgj6KXXH/T62ETSowzMv5GAr6IgZb A1uW/fSTzVrw== X-IronPort-AV: E=Sophos;i="5.83,284,1616482800"; d="scan'208";a="451455596" Received: from pbodapat-mobl.amr.corp.intel.com (HELO intel.com) ([10.252.143.92]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Jun 2021 09:58:37 -0700 Date: Fri, 18 Jun 2021 09:58:33 -0700 From: Ben Widawsky To: ira.weiny@intel.com Cc: Dan Williams , Jonathan Cameron , Alison Schofield , Vishal Verma , linux-cxl@vger.kernel.org Subject: Re: [PATCH V3] cxl/mem: Account for partitionable space in ram/pmem ranges Message-ID: <20210618165833.2jem3rshyy7szsm6@intel.com> References: <20210617221620.1904031-3-ira.weiny@intel.com> <20210618163129.1912453-1-ira.weiny@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210618163129.1912453-1-ira.weiny@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-cxl@vger.kernel.org On 21-06-18 09:31:29, ira.weiny@intel.com wrote: > From: Ira Weiny > > Memory devices may specify volatile only, persistent only, and > partitionable space which when added together result in a total capacity. > > If Identify Memory Device.Partition Alignment != 0 the device supports > partitionable space. This partitionable space can be split between > volatile and persistent space. The total volatile and persistent sizes > are reported in Get Partition Info. ie > > active volatile memory = volatile only + partitionable volatile > active persistent memory = persistent only + partitionable persistent > > Define cxl_mem_get_partition(), check for partitionable support, and use > cxl_mem_get_partition() if applicable. This doesn't look right to me, but I'll happily stand corrected. > > Reviewed-by: Jonathan Cameron > Signed-off-by: Ira Weiny > > --- > Changes for V3: > Johnathan > Stop over documenting 'in bytes'... :-D > > Changes for V2: > Jonathan > Account for Get Partition Info being optional > Fix documentation > Dan > Store the active capacities in struct cxl_mem > Make cxl_mem_get_partition() static until there is a > need to export it. > --- > drivers/cxl/mem.h | 5 +++ > drivers/cxl/pci.c | 96 ++++++++++++++++++++++++++++++++++++++++++++--- > 2 files changed, 96 insertions(+), 5 deletions(-) > > diff --git a/drivers/cxl/mem.h b/drivers/cxl/mem.h > index 9dc34418db36..8d7bd966a298 100644 > --- a/drivers/cxl/mem.h > +++ b/drivers/cxl/mem.h > @@ -79,5 +79,10 @@ struct cxl_mem { > u64 volatile_only_bytes; > u64 persistent_only_bytes; > u64 partition_align_bytes; > + > + u64 active_volatile_bytes; > + u64 active_persistent_bytes; > + u64 next_volatile_bytes; > + u64 next_persistent_bytes; > }; > #endif /* __CXL_MEM_H__ */ > diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c > index 94b7ee08ef67..3c8b7aa8c273 100644 > --- a/drivers/cxl/pci.c > +++ b/drivers/cxl/pci.c > @@ -1455,6 +1455,53 @@ static struct cxl_mbox_get_supported_logs *cxl_get_gsl(struct cxl_mem *cxlm) > return ret; > } > > +/** > + * cxl_mem_get_partition_info - Get partition info > + * @cxlm: The device to act on > + * @active_volatile_bytes: returned active volatile capacity > + * @active_persistent_bytes: returned active persistent capacity > + * @next_volatile_bytes: return next volatile capacity > + * @next_persistent_bytes: return next persistent capacity > + * > + * Retrieve the current partition info for the device specified. If not 0, the > + * 'next' values are pending and take affect on next cold reset. > + * > + * Return: 0 if no error: or the result of the mailbox command. > + * > + * See CXL @8.2.9.5.2.1 Get Partition Info > + */ > +static int cxl_mem_get_partition_info(struct cxl_mem *cxlm, > + u64 *active_volatile_bytes, > + u64 *active_persistent_bytes, > + u64 *next_volatile_bytes, > + u64 *next_persistent_bytes) > +{ > + struct cxl_mbox_get_partition_info { > + u64 active_volatile_cap; > + u64 active_persistent_cap; > + u64 next_volatile_cap; > + u64 next_persistent_cap; > + } __packed pi; > + int rc; > + > + rc = cxl_mem_mbox_send_cmd(cxlm, CXL_MBOX_OP_GET_PARTITION_INFO, > + NULL, 0, &pi, sizeof(pi)); > + if (rc) > + return rc; > + > + *active_volatile_bytes = le64_to_cpu(pi.active_volatile_cap); > + *active_persistent_bytes = le64_to_cpu(pi.active_persistent_cap); > + *next_volatile_bytes = le64_to_cpu(pi.next_volatile_cap); > + *next_persistent_bytes = le64_to_cpu(pi.next_volatile_cap); > + > + *active_volatile_bytes *= CXL_CAPACITY_MULTIPLIER; > + *active_persistent_bytes *= CXL_CAPACITY_MULTIPLIER; > + *next_volatile_bytes *= CXL_CAPACITY_MULTIPLIER; > + *next_persistent_bytes *= CXL_CAPACITY_MULTIPLIER; > + > + return 0; > +} > + > /** > * cxl_mem_enumerate_cmds() - Enumerate commands for a device. > * @cxlm: The device. > @@ -1573,18 +1620,53 @@ static int cxl_mem_identify(struct cxl_mem *cxlm) > cxlm->persistent_only_bytes, > cxlm->partition_align_bytes); > > + cxlm->lsa_size = le32_to_cpu(id.lsa_size); > + memcpy(cxlm->firmware_version, id.fw_revision, sizeof(id.fw_revision)); > + > + return 0; > +} > + > +static int cxl_mem_create_range_info(struct cxl_mem *cxlm) > +{ > + int rc; > + > + if (cxlm->partition_align_bytes == 0) { > + cxlm->ram_range.start = 0; > + cxlm->ram_range.end = cxlm->volatile_only_bytes - 1; > + cxlm->pmem_range.start = 0; > + cxlm->pmem_range.end = cxlm->persistent_only_bytes - 1; > + return 0; > + } > + > + rc = cxl_mem_get_partition_info(cxlm, > + &cxlm->active_volatile_bytes, > + &cxlm->active_persistent_bytes, > + &cxlm->next_volatile_bytes, > + &cxlm->next_persistent_bytes); > + if (rc < 0) { > + dev_err(&cxlm->pdev->dev, "Failed to query partition information\n"); > + return rc; > + } If the command is not supported, you're going to get back -ENXIO here and fail. I think what you want to do also is use IDENTIFY if PARTITION_INFO doesn't exist. > + > + dev_dbg(&cxlm->pdev->dev, "Get Partition Info\n" > + " active_volatile_bytes = %#llx\n" > + " active_persistent_bytes = %#llx\n" > + " next_volatile_bytes = %#llx\n" > + " next_persistent_bytes = %#llx\n", > + cxlm->active_volatile_bytes, > + cxlm->active_persistent_bytes, > + cxlm->next_volatile_bytes, > + cxlm->next_persistent_bytes); > + > /* > * TODO: enumerate DPA map, as 'ram' and 'pmem' do not alias. > * For now, only the capacity is exported in sysfs > */ > cxlm->ram_range.start = 0; > - cxlm->ram_range.end = cxlm->volatile_only_bytes - 1; > + cxlm->ram_range.end = cxlm->active_volatile_bytes - 1; > > cxlm->pmem_range.start = 0; > - cxlm->pmem_range.end = cxlm->persistent_only_bytes - 1; > - > - cxlm->lsa_size = le32_to_cpu(id.lsa_size); > - memcpy(cxlm->firmware_version, id.fw_revision, sizeof(id.fw_revision)); > + cxlm->pmem_range.end = cxlm->active_persistent_bytes - 1; > > return 0; > } > @@ -1618,6 +1700,10 @@ static int cxl_mem_probe(struct pci_dev *pdev, const struct pci_device_id *id) > if (rc) > return rc; > > + rc = cxl_mem_create_range_info(cxlm); > + if (rc) > + return rc; > + Assuming my assessment is correct, I think it's time to make cxl_mem_mbox_send_cmd grow a little bit better error handling. I'd recommend something like this and then checking for -ENOTSUPP. diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c index b1a5a18dba92..3b7d8a905393 100644 --- a/drivers/cxl/pci.c +++ b/drivers/cxl/pci.c @@ -92,6 +92,7 @@ struct mbox_cmd { size_t size_out; u16 return_code; #define CXL_MBOX_SUCCESS 0 +#define CXL_MBOX_UNSUPPORTED 0x15 }; static int cxl_mem_major; @@ -876,9 +877,15 @@ static int cxl_mem_mbox_send_cmd(struct cxl_mem *cxlm, u16 opcode, if (rc) return rc; - /* TODO: Map return code to proper kernel style errno */ - if (mbox_cmd.return_code != CXL_MBOX_SUCCESS) + switch (mbox_cmd.return_code) { + case CXL_MBOX_SUCCESS: + break; + case CXL_MBOX_UNSUPPORTED: + return -ENOTSUPP; + default: + /* TODO: Map return code to proper kernel style errno */ return -ENXIO; + } /* * Variable sized commands can't be validated and so it's up to the > return cxl_mem_add_memdev(cxlm); > } > > -- > 2.28.0.rc0.12.gb6a658bd00c9 >