From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 76644132117; Fri, 13 Sep 2024 18:08:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.176.79.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726250896; cv=none; b=WV0YAlRm1J054c+V9QnK42XnmTEsGaL3EqjGGD9VN0cYixspRvyW5g55SA9fNdD6EfmMcctM6udph4iVL94rZw+XPwtQ/nZv/SkPYIADzK6fAvaZ7bwzKYL2uYNNSho62s1PSZa1d2VVplTFRzKFg8ZpGTHb6sdSPXRN/vcyOcU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726250896; c=relaxed/simple; bh=DksrWtmDsvnuE000nzAvcl6FqrVUSZyUSb3lRWm2a5o=; h=Date:From:To:CC:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=Ad+IXS+4f8LE5+FceIUGf9ASLYoTKsActqUjKy2RCU7ka019jkjVjfS5eCsXg8SRd6Q51v3zxMtUNd6FE34Ndyl615BTiMAG0MktVowXOk7QbyBck5uiRTc9bPJNsGpR/30dTVeGG/CQgkoKfRJqSXTG286d1oI9MjLUxo7JKVY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=Huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=185.176.79.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=Huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.18.186.31]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4X52Gr3Zp2z6K60F; Sat, 14 Sep 2024 02:03:16 +0800 (CST) Received: from frapeml500008.china.huawei.com (unknown [7.182.85.71]) by mail.maildlp.com (Postfix) with ESMTPS id 0B4B214038F; Sat, 14 Sep 2024 02:08:11 +0800 (CST) Received: from localhost (10.48.150.243) by frapeml500008.china.huawei.com (7.182.85.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.39; Fri, 13 Sep 2024 20:08:10 +0200 Date: Fri, 13 Sep 2024 19:08:08 +0100 From: Jonathan Cameron To: CC: , , , , , , , , , Alejandro Lucero Subject: Re: [PATCH v3 17/20] cxl: allow region creation by type2 drivers Message-ID: <20240913190808.000010d0@Huawei.com> In-Reply-To: <20240907081836.5801-18-alejandro.lucero-palau@amd.com> References: <20240907081836.5801-1-alejandro.lucero-palau@amd.com> <20240907081836.5801-18-alejandro.lucero-palau@amd.com> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 4.1.0 (GTK 3.24.33; x86_64-w64-mingw32) Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: lhrpeml100004.china.huawei.com (7.191.162.219) To frapeml500008.china.huawei.com (7.182.85.71) On Sat, 7 Sep 2024 09:18:33 +0100 alejandro.lucero-palau@amd.com wrote: > From: Alejandro Lucero > > Creating a CXL region requires userspace intervention through the cxl > sysfs files. Type2 support should allow accelerator drivers to create > such cxl region from kernel code. > > Adding that functionality and integrating it with current support for > memory expanders. > > Based on https://lore.kernel.org/linux-cxl/168592159835.1948938.1647215579839222774.stgit@dwillia2-xfh.jf.intel.com/ > > Signed-off-by: Alejandro Lucero > Signed-off-by: Dan Williams Sign off doesn't make sense given Dan didn't sent the mail. Co-developed missing? Minor stuff inline, Jonathan > +static struct cxl_region *construct_region_begin(struct cxl_root_decoder *cxlrd, > + struct cxl_endpoint_decoder *cxled) > { > struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); > - struct cxl_port *port = cxlrd_to_port(cxlrd); > - struct range *hpa = &cxled->cxld.hpa_range; > struct cxl_region_params *p; > struct cxl_region *cxlr; > - struct resource *res; > - int rc; > + int err = 0; > > do { > cxlr = __create_region(cxlrd, cxled->mode, > @@ -3404,8 +3414,7 @@ static struct cxl_region *construct_region(struct cxl_root_decoder *cxlrd, > } while (IS_ERR(cxlr) && PTR_ERR(cxlr) == -EBUSY); > > if (IS_ERR(cxlr)) { > - dev_err(cxlmd->dev.parent, > - "%s:%s: %s failed assign region: %ld\n", > + dev_err(cxlmd->dev.parent, "%s:%s: %s failed assign region: %ld\n", > dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), > __func__, PTR_ERR(cxlr)); > return cxlr; > @@ -3415,19 +3424,41 @@ static struct cxl_region *construct_region(struct cxl_root_decoder *cxlrd, > p = &cxlr->params; > if (p->state >= CXL_CONFIG_INTERLEAVE_ACTIVE) { > dev_err(cxlmd->dev.parent, > - "%s:%s: %s autodiscovery interrupted\n", > + "%s:%s: %s region setup interrupted\n", > dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), > __func__); > - rc = -EBUSY; > - goto err; > + err = -EBUSY; > } > > + if (err) { > + construct_region_end(); Here I'd just release the semaphore not call this warpper as it's taken within this function I think? > + drop_region(cxlr); > + return ERR_PTR(err); > + } > + return cxlr; > +} > + > *res = DEFINE_RES_MEM_NAMED(hpa->start, range_len(hpa), > @@ -3444,6 +3475,7 @@ static struct cxl_region *construct_region(struct cxl_root_decoder *cxlrd, > __func__, dev_name(&cxlr->dev)); > } > > + p = &cxlr->params; > p->res = res; > p->interleave_ways = cxled->cxld.interleave_ways; > p->interleave_granularity = cxled->cxld.interleave_granularity; > @@ -3451,24 +3483,106 @@ static struct cxl_region *construct_region(struct cxl_root_decoder *cxlrd, > > rc = sysfs_update_group(&cxlr->dev.kobj, get_cxl_region_target_group()); > if (rc) > - goto err; > + goto out; > > dev_dbg(cxlmd->dev.parent, "%s:%s: %s %s res: %pr iw: %d ig: %d\n", > - dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), __func__, > - dev_name(&cxlr->dev), p->res, p->interleave_ways, > - p->interleave_granularity); > + dev_name(&cxlmd->dev), > + dev_name(&cxled->cxld.dev), __func__, Avoid reformatting unless necessary. Hard to tell what changed if anything. > + dev_name(&cxlr->dev), p->res, > + p->interleave_ways, > + p->interleave_granularity); > > /* ...to match put_device() in cxl_add_to_region() */ > get_device(&cxlr->dev); > up_write(&cxl_region_rwsem); > > +out: > + construct_region_end(); As below. I'd have separate error handling path. Same in the other paths. > + if (rc) { > + drop_region(cxlr); > + return ERR_PTR(rc); > + } > return cxlr; > +} > > -err: > - up_write(&cxl_region_rwsem); > - devm_release_action(port->uport_dev, unregister_region, cxlr); > - return ERR_PTR(rc); > +static struct cxl_region * > +__construct_new_region(struct cxl_root_decoder *cxlrd, > + struct cxl_endpoint_decoder *cxled) > +{ > + struct cxl_decoder *cxld = &cxlrd->cxlsd.cxld; > + struct cxl_region_params *p; > + resource_size_t size = 0; set in all paths that use it. > + struct cxl_region *cxlr; > + int rc; > + > + cxlr = construct_region_begin(cxlrd, cxled); > + if (IS_ERR(cxlr)) > + return cxlr; > + > + rc = set_interleave_ways(cxlr, 1); > + if (rc) > + goto out; > + > + rc = set_interleave_granularity(cxlr, cxld->interleave_granularity); > + if (rc) > + goto out; > + > + size = resource_size(cxled->dpa_res); > + only used once rc = alloc_hpa(cxlr, resource_size(cxled->dpa_res)); > + rc = alloc_hpa(cxlr, size); > + if (rc) > + goto out; > + > + down_read(&cxl_dpa_rwsem); > + rc = cxl_region_attach(cxlr, cxled, 0); > + up_read(&cxl_dpa_rwsem); > + > + if (rc) > + goto out; > + > + rc = cxl_region_decode_commit(cxlr); > + if (rc) > + goto out; > + > + p = &cxlr->params; > + p->state = CXL_CONFIG_COMMIT; > +out: I'd break out a separate error handling path and just duplicate the next line. > + construct_region_end(); > + if (rc) { > + drop_region(cxlr); > + return ERR_PTR(rc); > + } > + return cxlr; > +}