[6/8] device-dax: Move resource pinning+mapping into the common driver

Message ID	154095560048.3271337.5958710475937860522.stgit@dwillia2-desk3.amr.corp.intel.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <owner-linux-mm@kvack.org> Received-SPF: pass (google.com: domain of dan.j.williams@intel.com designates 192.55.52.120 as permitted sender) client-ip=192.55.52.120; Subject: [PATCH 6/8] device-dax: Move resource pinning+mapping into the common driver From: Dan Williams <dan.j.williams@intel.com> To: linux-nvdimm@lists.01.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, dave.hansen@linux.intel.com Date: Tue, 30 Oct 2018 20:13:20 -0700 Message-ID: <154095560048.3271337.5958710475937860522.stgit@dwillia2-desk3.amr.corp.intel.com> In-Reply-To: <154095556915.3271337.12581429676272726902.stgit@dwillia2-desk3.amr.corp.intel.com> References: <154095556915.3271337.12581429676272726902.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.18-2-gc94f MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Precedence: bulk
Series	Introduce a device-dax bus-based device-model \| expand [0/8] Introduce a device-dax bus-based device-model [1/8] device-dax: Kill dax_region ida [2/8] device-dax: Kill dax_region base [3/8] device-dax: Remove multi-resource infrastructure [4/8] device-dax: Start defining a dax bus model [5/8] device-dax: Introduce bus + driver model [6/8] device-dax: Move resource pinning+mapping into the common driver [7/8] device-dax: Add support for a dax override driver [8/8] device-dax: Add /sys/class/dax backwards compatibility

diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index 0cff32102c4c..69aae2cbd45f 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -1,5 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 /* Copyright(c) 2017-2018 Intel Corporation. All rights reserved. */ +#include <linux/memremap.h> #include <linux/device.h> #include <linux/slab.h> #include <linux/dax.h> @@ -206,7 +207,8 @@ static void unregister_dev_dax(void *dev) put_device(dev); } -struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id) +struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id, + struct dev_pagemap *pgmap) { struct device *parent = dax_region->dev; struct dax_device *dax_dev; @@ -222,6 +224,8 @@ struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id) if (!dev_dax) return ERR_PTR(-ENOMEM); + memcpy(&dev_dax->pgmap, pgmap, sizeof(*pgmap)); + /* * No 'host' or dax_operations since there is no access to this * device outside of mmap of the resulting character device. diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h index ea509504df3a..e08e0c394983 100644 --- a/drivers/dax/bus.h +++ b/drivers/dax/bus.h @@ -10,7 +10,8 @@ struct dax_region; void dax_region_put(struct dax_region *dax_region); struct dax_region *alloc_dax_region(struct device *parent, int region_id, struct resource *res, unsigned int align, unsigned long flags); -struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id); +struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id, + struct dev_pagemap *pgmap); int __dax_driver_register(struct device_driver *drv, struct module *module, const char *mod_name); #define dax_driver_register(driver) \ diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h index c3a121700837..a82ce48f5884 100644 --- a/drivers/dax/dax-private.h +++ b/drivers/dax/dax-private.h @@ -42,15 +42,22 @@ struct dax_region { }; /** - * struct dev_dax - instance data for a subdivision of a dax region + * struct dev_dax - instance data for a subdivision of a dax region, and + * data while the device is activated in the driver. * @region - parent region * @dax_dev - core dax functionality * @dev - device core + * @pgmap - pgmap for memmap setup / lifetime (driver owned) + * @ref: pgmap reference count (driver owned) + * @cmp: @ref final put completion (driver owned) */ struct dev_dax { struct dax_region *region; struct dax_device *dax_dev; struct device dev; + struct dev_pagemap pgmap; + struct percpu_ref ref; + struct completion cmp; }; static inline struct dev_dax *to_dev_dax(struct device *dev) diff --git a/drivers/dax/device.c b/drivers/dax/device.c index f55829404a24..967bab097013 100644 --- a/drivers/dax/device.c +++ b/drivers/dax/device.c @@ -1,5 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 /* Copyright(c) 2016-2018 Intel Corporation. All rights reserved. */ +#include <linux/memremap.h> #include <linux/pagemap.h> #include <linux/module.h> #include <linux/device.h> @@ -13,6 +14,38 @@ #include "dax-private.h" #include "bus.h" +static struct dev_dax *ref_to_dev_dax(struct percpu_ref *ref) +{ + return container_of(ref, struct dev_dax, ref); +} + +static void dev_dax_percpu_release(struct percpu_ref *ref) +{ + struct dev_dax *dev_dax = ref_to_dev_dax(ref); + + dev_dbg(&dev_dax->dev, "%s\n", __func__); + complete(&dev_dax->cmp); +} + +static void dev_dax_percpu_exit(void *data) +{ + struct percpu_ref *ref = data; + struct dev_dax *dev_dax = ref_to_dev_dax(ref); + + dev_dbg(&dev_dax->dev, "%s\n", __func__); + wait_for_completion(&dev_dax->cmp); + percpu_ref_exit(ref); +} + +static void dev_dax_percpu_kill(void *data) +{ + struct percpu_ref *ref = data; + struct dev_dax *dev_dax = ref_to_dev_dax(ref); + + dev_dbg(&dev_dax->dev, "%s\n", __func__); + percpu_ref_kill(ref); +} + static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma, const char *func) { @@ -416,10 +449,42 @@ static int dev_dax_probe(struct device *dev) { struct dev_dax *dev_dax = to_dev_dax(dev); struct dax_device *dax_dev = dev_dax->dax_dev; + struct resource *res = &dev_dax->region->res; struct inode *inode; struct cdev *cdev; + void *addr; int rc; + /* 1:1 map region resource range to device-dax instance range */ + if (!devm_request_mem_region(dev, res->start, resource_size(res), + dev_name(dev))) { + dev_warn(dev, "could not reserve region %pR\n", res); + return -EBUSY; + } + + init_completion(&dev_dax->cmp); + rc = percpu_ref_init(&dev_dax->ref, dev_dax_percpu_release, 0, + GFP_KERNEL); + if (rc) + return rc; + + rc = devm_add_action_or_reset(dev, dev_dax_percpu_exit, &dev_dax->ref); + if (rc) + return rc; + + dev_dax->pgmap.ref = &dev_dax->ref; + addr = devm_memremap_pages(dev, &dev_dax->pgmap); + if (IS_ERR(addr)) { + devm_remove_action(dev, dev_dax_percpu_exit, &dev_dax->ref); + percpu_ref_exit(&dev_dax->ref); + return PTR_ERR(addr); + } + + rc = devm_add_action_or_reset(dev, dev_dax_percpu_kill, + &dev_dax->ref); + if (rc) + return rc; + inode = dax_inode(dax_dev); cdev = inode->i_cdev; cdev_init(cdev, &dax_fops); diff --git a/drivers/dax/pmem.c b/drivers/dax/pmem.c index c94f17e662bd..d3cefa7868ac 100644 --- a/drivers/dax/pmem.c +++ b/drivers/dax/pmem.c @@ -18,55 +18,16 @@ #include "../nvdimm/nd.h" #include "bus.h" -struct dax_pmem { - struct device *dev; - struct percpu_ref ref; - struct dev_pagemap pgmap; - struct completion cmp; -}; - -static struct dax_pmem *to_dax_pmem(struct percpu_ref *ref) -{ - return container_of(ref, struct dax_pmem, ref); -} - -static void dax_pmem_percpu_release(struct percpu_ref *ref) -{ - struct dax_pmem *dax_pmem = to_dax_pmem(ref); - - dev_dbg(dax_pmem->dev, "trace\n"); - complete(&dax_pmem->cmp); -} - -static void dax_pmem_percpu_exit(void *data) -{ - struct percpu_ref *ref = data; - struct dax_pmem *dax_pmem = to_dax_pmem(ref); - - dev_dbg(dax_pmem->dev, "trace\n"); - wait_for_completion(&dax_pmem->cmp); - percpu_ref_exit(ref); -} - -static void dax_pmem_percpu_kill(void *data) -{ - struct percpu_ref *ref = data; - struct dax_pmem *dax_pmem = to_dax_pmem(ref); - - dev_dbg(dax_pmem->dev, "trace\n"); - percpu_ref_kill(ref); -} - static int dax_pmem_probe(struct device *dev) { - void *addr; struct resource res; int rc, id, region_id; + resource_size_t offset; struct nd_pfn_sb *pfn_sb; struct dev_dax *dev_dax; - struct dax_pmem *dax_pmem; struct nd_namespace_io *nsio; struct dax_region *dax_region; + struct dev_pagemap pgmap = { 0 }; struct nd_namespace_common *ndns; struct nd_dax *nd_dax = to_nd_dax(dev); struct nd_pfn *nd_pfn = &nd_dax->nd_pfn; @@ -76,68 +37,37 @@ static int dax_pmem_probe(struct device *dev) return PTR_ERR(ndns); nsio = to_nd_namespace_io(&ndns->dev); - dax_pmem = devm_kzalloc(dev, sizeof(*dax_pmem), GFP_KERNEL); - if (!dax_pmem) - return -ENOMEM; - /* parse the 'pfn' info block via ->rw_bytes */ rc = devm_nsio_enable(dev, nsio); if (rc) return rc; - rc = nvdimm_setup_pfn(nd_pfn, &dax_pmem->pgmap); + rc = nvdimm_setup_pfn(nd_pfn, &pgmap); if (rc) return rc; devm_nsio_disable(dev, nsio); - pfn_sb = nd_pfn->pfn_sb; - - if (!devm_request_mem_region(dev, nsio->res.start, - resource_size(&nsio->res), + /* reserve the metadata area, device-dax will reserve the data */ + pfn_sb = nd_pfn->pfn_sb; + offset = le64_to_cpu(pfn_sb->dataoff); + if (!devm_request_mem_region(dev, nsio->res.start, offset, dev_name(&ndns->dev))) { - dev_warn(dev, "could not reserve region %pR\n", &nsio->res); - return -EBUSY; - } - - dax_pmem->dev = dev; - init_completion(&dax_pmem->cmp); - rc = percpu_ref_init(&dax_pmem->ref, dax_pmem_percpu_release, 0, - GFP_KERNEL); - if (rc) - return rc; - - rc = devm_add_action(dev, dax_pmem_percpu_exit, &dax_pmem->ref); - if (rc) { - percpu_ref_exit(&dax_pmem->ref); - return rc; - } - - dax_pmem->pgmap.ref = &dax_pmem->ref; - addr = devm_memremap_pages(dev, &dax_pmem->pgmap); - if (IS_ERR(addr)) { - devm_remove_action(dev, dax_pmem_percpu_exit, &dax_pmem->ref); - percpu_ref_exit(&dax_pmem->ref); - return PTR_ERR(addr); - } - - rc = devm_add_action_or_reset(dev, dax_pmem_percpu_kill, - &dax_pmem->ref); - if (rc) - return rc; - - /* adjust the dax_region resource to the start of data */ - memcpy(&res, &dax_pmem->pgmap.res, sizeof(res)); - res.start += le64_to_cpu(pfn_sb->dataoff); + dev_warn(dev, "could not reserve metadata\n"); + return -EBUSY; + } rc = sscanf(dev_name(&ndns->dev), "namespace%d.%d", &region_id, &id); if (rc != 2) return -EINVAL; + /* adjust the dax_region resource to the start of data */ + memcpy(&res, &pgmap.res, sizeof(res)); + res.start += offset; dax_region = alloc_dax_region(dev, region_id, &res, le32_to_cpu(pfn_sb->align), PFN_DEV|PFN_MAP); if (!dax_region) return -ENOMEM; - dev_dax = devm_create_dev_dax(dax_region, id); + dev_dax = devm_create_dev_dax(dax_region, id, &pgmap); /* child dev_dax instances now own the lifetime of the dax_region */ dax_region_put(dax_region);

[6/8] device-dax: Move resource pinning+mapping into the common driver

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