[mirror_ubuntu-zesty-kernel.git] / drivers / nvdimm / pmem.c

/*
 * Persistent Memory Driver
 *
 * Copyright (c) 2014-2015, Intel Corporation.
 * Copyright (c) 2015, Christoph Hellwig <hch@lst.de>.
 * Copyright (c) 2015, Boaz Harrosh <boaz@plexistor.com>.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 */

#include <asm/cacheflush.h>
#include <linux/blkdev.h>
#include <linux/hdreg.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/memory_hotplug.h>
#include <linux/moduleparam.h>
#include <linux/vmalloc.h>
#include <linux/slab.h>
#include <linux/pmem.h>
#include <linux/nd.h>
#include "pfn.h"
#include "nd.h"

struct pmem_device {
	struct request_queue	*pmem_queue;
	struct gendisk		*pmem_disk;
	struct nd_namespace_common *ndns;

	/* One contiguous memory region per device */
	phys_addr_t		phys_addr;
	/* when non-zero this device is hosting a 'pfn' instance */
	phys_addr_t		data_offset;
	void __pmem		*virt_addr;
	size_t			size;
};

static int pmem_major;

static void pmem_do_bvec(struct pmem_device *pmem, struct page *page,
			unsigned int len, unsigned int off, int rw,
			sector_t sector)
{
	void *mem = kmap_atomic(page);
	phys_addr_t pmem_off = sector * 512 + pmem->data_offset;
	void __pmem *pmem_addr = pmem->virt_addr + pmem_off;

	if (rw == READ) {
		memcpy_from_pmem(mem + off, pmem_addr, len);
		flush_dcache_page(page);
	} else {
		flush_dcache_page(page);
		memcpy_to_pmem(pmem_addr, mem + off, len);
	}

	kunmap_atomic(mem);
}

static void pmem_make_request(struct request_queue *q, struct bio *bio)
{
	bool do_acct;
	unsigned long start;
	struct bio_vec bvec;
	struct bvec_iter iter;
	struct block_device *bdev = bio->bi_bdev;
	struct pmem_device *pmem = bdev->bd_disk->private_data;

	do_acct = nd_iostat_start(bio, &start);
	bio_for_each_segment(bvec, bio, iter)
		pmem_do_bvec(pmem, bvec.bv_page, bvec.bv_len, bvec.bv_offset,
				bio_data_dir(bio), iter.bi_sector);
	if (do_acct)
		nd_iostat_end(bio, start);

	if (bio_data_dir(bio))
		wmb_pmem();

	bio_endio(bio);
}

static int pmem_rw_page(struct block_device *bdev, sector_t sector,
		       struct page *page, int rw)
{
	struct pmem_device *pmem = bdev->bd_disk->private_data;

	pmem_do_bvec(pmem, page, PAGE_CACHE_SIZE, 0, rw, sector);
	if (rw & WRITE)
		wmb_pmem();
	page_endio(page, rw & WRITE, 0);

	return 0;
}

static long pmem_direct_access(struct block_device *bdev, sector_t sector,
		      void __pmem **kaddr, unsigned long *pfn)
{
	struct pmem_device *pmem = bdev->bd_disk->private_data;
	resource_size_t offset = sector * 512 + pmem->data_offset;
	resource_size_t size;

	if (pmem->data_offset) {
		/*
		 * Limit the direct_access() size to what is covered by
		 * the memmap
		 */
		size = (pmem->size - offset) & ~ND_PFN_MASK;
	} else
		size = pmem->size - offset;

	/* FIXME convert DAX to comprehend that this mapping has a lifetime */
	*kaddr = pmem->virt_addr + offset;
	*pfn = (pmem->phys_addr + offset) >> PAGE_SHIFT;

	return size;
}

static const struct block_device_operations pmem_fops = {
	.owner =		THIS_MODULE,
	.rw_page =		pmem_rw_page,
	.direct_access =	pmem_direct_access,
	.revalidate_disk =	nvdimm_revalidate_disk,
};

static struct pmem_device *pmem_alloc(struct device *dev,
		struct resource *res, int id)
{
	struct pmem_device *pmem;

	pmem = devm_kzalloc(dev, sizeof(*pmem), GFP_KERNEL);
	if (!pmem)
		return ERR_PTR(-ENOMEM);

	pmem->phys_addr = res->start;
	pmem->size = resource_size(res);
	if (!arch_has_wmb_pmem())
		dev_warn(dev, "unable to guarantee persistence of writes\n");

	if (!devm_request_mem_region(dev, pmem->phys_addr, pmem->size,
			dev_name(dev))) {
		dev_warn(dev, "could not reserve region [0x%pa:0x%zx]\n",
				&pmem->phys_addr, pmem->size);
		return ERR_PTR(-EBUSY);
	}

	if (pmem_should_map_pages(dev)) {
		void *addr = devm_memremap_pages(dev, res);

		if (IS_ERR(addr))
			return addr;
		pmem->virt_addr = (void __pmem *) addr;
	} else {
		pmem->virt_addr = memremap_pmem(dev, pmem->phys_addr,
				pmem->size);
		if (!pmem->virt_addr)
			return ERR_PTR(-ENXIO);
	}

	return pmem;
}

static void pmem_detach_disk(struct pmem_device *pmem)
{
	if (!pmem->pmem_disk)
		return;

	del_gendisk(pmem->pmem_disk);
	put_disk(pmem->pmem_disk);
	blk_cleanup_queue(pmem->pmem_queue);
}

static int pmem_attach_disk(struct device *dev,
		struct nd_namespace_common *ndns, struct pmem_device *pmem)
{
	struct gendisk *disk;

	pmem->pmem_queue = blk_alloc_queue(GFP_KERNEL);
	if (!pmem->pmem_queue)
		return -ENOMEM;

	blk_queue_make_request(pmem->pmem_queue, pmem_make_request);
	blk_queue_physical_block_size(pmem->pmem_queue, PAGE_SIZE);
	blk_queue_max_hw_sectors(pmem->pmem_queue, UINT_MAX);
	blk_queue_bounce_limit(pmem->pmem_queue, BLK_BOUNCE_ANY);
	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, pmem->pmem_queue);

	disk = alloc_disk(0);
	if (!disk) {
		blk_cleanup_queue(pmem->pmem_queue);
		return -ENOMEM;
	}

	disk->major		= pmem_major;
	disk->first_minor	= 0;
	disk->fops		= &pmem_fops;
	disk->private_data	= pmem;
	disk->queue		= pmem->pmem_queue;
	disk->flags		= GENHD_FL_EXT_DEVT;
	nvdimm_namespace_disk_name(ndns, disk->disk_name);
	disk->driverfs_dev = dev;
	set_capacity(disk, (pmem->size - pmem->data_offset) / 512);
	pmem->pmem_disk = disk;

	add_disk(disk);
	revalidate_disk(disk);

	return 0;
}

static int pmem_rw_bytes(struct nd_namespace_common *ndns,
		resource_size_t offset, void *buf, size_t size, int rw)
{
	struct pmem_device *pmem = dev_get_drvdata(ndns->claim);

	if (unlikely(offset + size > pmem->size)) {
		dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n");
		return -EFAULT;
	}

	if (rw == READ)
		memcpy_from_pmem(buf, pmem->virt_addr + offset, size);
	else {
		memcpy_to_pmem(pmem->virt_addr + offset, buf, size);
		wmb_pmem();
	}

	return 0;
}

static int nd_pfn_init(struct nd_pfn *nd_pfn)
{
	struct nd_pfn_sb *pfn_sb = kzalloc(sizeof(*pfn_sb), GFP_KERNEL);
	struct pmem_device *pmem = dev_get_drvdata(&nd_pfn->dev);
	struct nd_namespace_common *ndns = nd_pfn->ndns;
	struct nd_region *nd_region;
	unsigned long npfns;
	phys_addr_t offset;
	u64 checksum;
	int rc;

	if (!pfn_sb)
		return -ENOMEM;

	nd_pfn->pfn_sb = pfn_sb;
	rc = nd_pfn_validate(nd_pfn);
	if (rc == 0 || rc == -EBUSY)
		return rc;

	/* section alignment for simple hotplug */
	if (nvdimm_namespace_capacity(ndns) < ND_PFN_ALIGN
			|| pmem->phys_addr & ND_PFN_MASK)
		return -ENODEV;

	nd_region = to_nd_region(nd_pfn->dev.parent);
	if (nd_region->ro) {
		dev_info(&nd_pfn->dev,
				"%s is read-only, unable to init metadata\n",
				dev_name(&nd_region->dev));
		goto err;
	}

	memset(pfn_sb, 0, sizeof(*pfn_sb));
	npfns = (pmem->size - SZ_8K) / SZ_4K;
	/*
	 * Note, we use 64 here for the standard size of struct page,
	 * debugging options may cause it to be larger in which case the
	 * implementation will limit the pfns advertised through
	 * ->direct_access() to those that are included in the memmap.
	 */
	if (nd_pfn->mode == PFN_MODE_PMEM)
		offset = ALIGN(SZ_8K + 64 * npfns, PMD_SIZE);
	else if (nd_pfn->mode == PFN_MODE_RAM)
		offset = SZ_8K;
	else
		goto err;

	npfns = (pmem->size - offset) / SZ_4K;
	pfn_sb->mode = cpu_to_le32(nd_pfn->mode);
	pfn_sb->dataoff = cpu_to_le64(offset);
	pfn_sb->npfns = cpu_to_le64(npfns);
	memcpy(pfn_sb->signature, PFN_SIG, PFN_SIG_LEN);
	memcpy(pfn_sb->uuid, nd_pfn->uuid, 16);
	pfn_sb->version_major = cpu_to_le16(1);
	checksum = nd_sb_checksum((struct nd_gen_sb *) pfn_sb);
	pfn_sb->checksum = cpu_to_le64(checksum);

	rc = nvdimm_write_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb));
	if (rc)
		goto err;

	return 0;
 err:
	nd_pfn->pfn_sb = NULL;
	kfree(pfn_sb);
	return -ENXIO;
}

static int nvdimm_namespace_detach_pfn(struct nd_namespace_common *ndns)
{
	struct nd_pfn *nd_pfn = to_nd_pfn(ndns->claim);
	struct pmem_device *pmem;

	/* free pmem disk */
	pmem = dev_get_drvdata(&nd_pfn->dev);
	pmem_detach_disk(pmem);

	/* release nd_pfn resources */
	kfree(nd_pfn->pfn_sb);
	nd_pfn->pfn_sb = NULL;

	return 0;
}

static int nvdimm_namespace_attach_pfn(struct nd_namespace_common *ndns)
{
	struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
	struct nd_pfn *nd_pfn = to_nd_pfn(ndns->claim);
	struct device *dev = &nd_pfn->dev;
	struct vmem_altmap *altmap;
	struct nd_region *nd_region;
	struct nd_pfn_sb *pfn_sb;
	struct pmem_device *pmem;
	phys_addr_t offset;
	int rc;

	if (!nd_pfn->uuid || !nd_pfn->ndns)
		return -ENODEV;

	nd_region = to_nd_region(dev->parent);
	rc = nd_pfn_init(nd_pfn);
	if (rc)
		return rc;

	if (PAGE_SIZE != SZ_4K) {
		dev_err(dev, "only supported on systems with 4K PAGE_SIZE\n");
		return -ENXIO;
	}
	if (nsio->res.start & ND_PFN_MASK) {
		dev_err(dev, "%s not memory hotplug section aligned\n",
				dev_name(&ndns->dev));
		return -ENXIO;
	}

	pfn_sb = nd_pfn->pfn_sb;
	offset = le64_to_cpu(pfn_sb->dataoff);
	nd_pfn->mode = le32_to_cpu(nd_pfn->pfn_sb->mode);
	if (nd_pfn->mode == PFN_MODE_RAM) {
		if (offset != SZ_8K)
			return -EINVAL;
		nd_pfn->npfns = le64_to_cpu(pfn_sb->npfns);
		altmap = NULL;
	} else {
		rc = -ENXIO;
		goto err;
	}

	/* establish pfn range for lookup, and switch to direct map */
	pmem = dev_get_drvdata(dev);
	memunmap_pmem(dev, pmem->virt_addr);
	pmem->virt_addr = (void __pmem *)devm_memremap_pages(dev, &nsio->res);
	if (IS_ERR(pmem->virt_addr)) {
		rc = PTR_ERR(pmem->virt_addr);
		goto err;
	}

	/* attach pmem disk in "pfn-mode" */
	pmem->data_offset = offset;
	rc = pmem_attach_disk(dev, ndns, pmem);
	if (rc)
		goto err;

	return rc;
 err:
	nvdimm_namespace_detach_pfn(ndns);
	return rc;
}

static int nd_pmem_probe(struct device *dev)
{
	struct nd_region *nd_region = to_nd_region(dev->parent);
	struct nd_namespace_common *ndns;
	struct nd_namespace_io *nsio;
	struct pmem_device *pmem;

	ndns = nvdimm_namespace_common_probe(dev);
	if (IS_ERR(ndns))
		return PTR_ERR(ndns);

	nsio = to_nd_namespace_io(&ndns->dev);
	pmem = pmem_alloc(dev, &nsio->res, nd_region->id);
	if (IS_ERR(pmem))
		return PTR_ERR(pmem);

	pmem->ndns = ndns;
	dev_set_drvdata(dev, pmem);
	ndns->rw_bytes = pmem_rw_bytes;

	if (is_nd_btt(dev))
		return nvdimm_namespace_attach_btt(ndns);

	if (is_nd_pfn(dev))
		return nvdimm_namespace_attach_pfn(ndns);

	if (nd_btt_probe(ndns, pmem) == 0) {
		/* we'll come back as btt-pmem */
		return -ENXIO;
	}

	if (nd_pfn_probe(ndns, pmem) == 0) {
		/* we'll come back as pfn-pmem */
		return -ENXIO;
	}

	return pmem_attach_disk(dev, ndns, pmem);
}

static int nd_pmem_remove(struct device *dev)
{
	struct pmem_device *pmem = dev_get_drvdata(dev);

	if (is_nd_btt(dev))
		nvdimm_namespace_detach_btt(pmem->ndns);
	else if (is_nd_pfn(dev))
		nvdimm_namespace_detach_pfn(pmem->ndns);
	else
		pmem_detach_disk(pmem);

	return 0;
}

MODULE_ALIAS("pmem");
MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_IO);
MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_PMEM);
static struct nd_device_driver nd_pmem_driver = {
	.probe = nd_pmem_probe,
	.remove = nd_pmem_remove,
	.drv = {
		.name = "nd_pmem",
	},
	.type = ND_DRIVER_NAMESPACE_IO | ND_DRIVER_NAMESPACE_PMEM,
};

static int __init pmem_init(void)
{
	int error;

	pmem_major = register_blkdev(0, "pmem");
	if (pmem_major < 0)
		return pmem_major;

	error = nd_driver_register(&nd_pmem_driver);
	if (error) {
		unregister_blkdev(pmem_major, "pmem");
		return error;
	}

	return 0;
}
module_init(pmem_init);

static void pmem_exit(void)
{
	driver_unregister(&nd_pmem_driver.drv);
	unregister_blkdev(pmem_major, "pmem");
}
module_exit(pmem_exit);

MODULE_AUTHOR("Ross Zwisler <ross.zwisler@linux.intel.com>");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
9e853f23 RZ	1	/*
	2	* Persistent Memory Driver
	3	*
9f53f9fa	4	* Copyright (c) 2014-2015, Intel Corporation.
9e853f23 RZ	5	* Copyright (c) 2015, Christoph Hellwig <hch@lst.de>.
	6	* Copyright (c) 2015, Boaz Harrosh <boaz@plexistor.com>.
	7	*
	8	* This program is free software; you can redistribute it and/or modify it
	9	* under the terms and conditions of the GNU General Public License,
	10	* version 2, as published by the Free Software Foundation.
	11	*
	12	* This program is distributed in the hope it will be useful, but WITHOUT
	13	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	14	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	15	* more details.
	16	*/
	17
	18	#include <asm/cacheflush.h>
	19	#include <linux/blkdev.h>
	20	#include <linux/hdreg.h>
	21	#include <linux/init.h>
	22	#include <linux/platform_device.h>
	23	#include <linux/module.h>
32ab0a3f	24	#include <linux/memory_hotplug.h>
9e853f23	25	#include <linux/moduleparam.h>
32ab0a3f	26	#include <linux/vmalloc.h>
9e853f23	27	#include <linux/slab.h>
61031952	28	#include <linux/pmem.h>
9f53f9fa	29	#include <linux/nd.h>
32ab0a3f	30	#include "pfn.h"
9f53f9fa	31	#include "nd.h"
9e853f23 RZ	32
	33	struct pmem_device {
	34	struct request_queue *pmem_queue;
	35	struct gendisk *pmem_disk;
32ab0a3f	36	struct nd_namespace_common *ndns;
9e853f23 RZ	37
	38	/* One contiguous memory region per device */
	39	phys_addr_t phys_addr;
32ab0a3f DW	40	/* when non-zero this device is hosting a 'pfn' instance */
32ab0a3f DW	41	phys_addr_t data_offset;
61031952	42	void __pmem *virt_addr;
9e853f23 RZ	43	size_t size;
	44	};
	45
	46	static int pmem_major;
9e853f23 RZ	47
	48	static void pmem_do_bvec(struct pmem_device pmem, struct page page,
	49	unsigned int len, unsigned int off, int rw,
	50	sector_t sector)
	51	{
	52	void *mem = kmap_atomic(page);
32ab0a3f	53	phys_addr_t pmem_off = sector * 512 + pmem->data_offset;
61031952	54	void __pmem *pmem_addr = pmem->virt_addr + pmem_off;
9e853f23 RZ	55
9e853f23 RZ	56	if (rw == READ) {
61031952	57	memcpy_from_pmem(mem + off, pmem_addr, len);
9e853f23 RZ	58	flush_dcache_page(page);
	59	} else {
	60	flush_dcache_page(page);
61031952	61	memcpy_to_pmem(pmem_addr, mem + off, len);
9e853f23 RZ	62	}
	63
	64	kunmap_atomic(mem);
	65	}
	66
	67	static void pmem_make_request(struct request_queue q, struct bio bio)
	68	{
f0dc089c DW	69	bool do_acct;
f0dc089c DW	70	unsigned long start;
9e853f23	71	struct bio_vec bvec;
9e853f23	72	struct bvec_iter iter;
edc870e5 DW	73	struct block_device *bdev = bio->bi_bdev;
edc870e5 DW	74	struct pmem_device *pmem = bdev->bd_disk->private_data;
9e853f23	75
f0dc089c	76	do_acct = nd_iostat_start(bio, &start);
edc870e5	77	bio_for_each_segment(bvec, bio, iter)
9e853f23	78	pmem_do_bvec(pmem, bvec.bv_page, bvec.bv_len, bvec.bv_offset,
edc870e5	79	bio_data_dir(bio), iter.bi_sector);
f0dc089c DW	80	if (do_acct)
f0dc089c DW	81	nd_iostat_end(bio, start);
61031952 RZ	82
	83	if (bio_data_dir(bio))
	84	wmb_pmem();
	85
4246a0b6	86	bio_endio(bio);
9e853f23 RZ	87	}
	88
	89	static int pmem_rw_page(struct block_device *bdev, sector_t sector,
	90	struct page *page, int rw)
	91	{
	92	struct pmem_device *pmem = bdev->bd_disk->private_data;
	93
	94	pmem_do_bvec(pmem, page, PAGE_CACHE_SIZE, 0, rw, sector);
ba8fe0f8 RZ	95	if (rw & WRITE)
ba8fe0f8 RZ	96	wmb_pmem();
9e853f23 RZ	97	page_endio(page, rw & WRITE, 0);
	98
	99	return 0;
	100	}
	101
	102	static long pmem_direct_access(struct block_device *bdev, sector_t sector,
cb389b9c	103	void __pmem *kaddr, unsigned long pfn)
9e853f23 RZ	104	{
9e853f23 RZ	105	struct pmem_device *pmem = bdev->bd_disk->private_data;
32ab0a3f DW	106	resource_size_t offset = sector * 512 + pmem->data_offset;
	107	resource_size_t size;
	108
	109	if (pmem->data_offset) {
	110	/*
	111	* Limit the direct_access() size to what is covered by
	112	* the memmap
	113	*/
	114	size = (pmem->size - offset) & ~ND_PFN_MASK;
	115	} else
	116	size = pmem->size - offset;
9e853f23	117
61031952	118	/* FIXME convert DAX to comprehend that this mapping has a lifetime */
e2e05394	119	*kaddr = pmem->virt_addr + offset;
9e853f23 RZ	120	*pfn = (pmem->phys_addr + offset) >> PAGE_SHIFT;
9e853f23 RZ	121
32ab0a3f	122	return size;
9e853f23 RZ	123	}
	124
	125	static const struct block_device_operations pmem_fops = {
	126	.owner = THIS_MODULE,
	127	.rw_page = pmem_rw_page,
	128	.direct_access = pmem_direct_access,
58138820	129	.revalidate_disk = nvdimm_revalidate_disk,
9e853f23 RZ	130	};
9e853f23 RZ	131
9f53f9fa DW	132	static struct pmem_device pmem_alloc(struct device dev,
9f53f9fa DW	133	struct resource *res, int id)
9e853f23 RZ	134	{
9e853f23 RZ	135	struct pmem_device *pmem;
9e853f23	136
708ab62b	137	pmem = devm_kzalloc(dev, sizeof(*pmem), GFP_KERNEL);
9e853f23	138	if (!pmem)
8c2f7e86	139	return ERR_PTR(-ENOMEM);
9e853f23 RZ	140
	141	pmem->phys_addr = res->start;
	142	pmem->size = resource_size(res);
96601adb	143	if (!arch_has_wmb_pmem())
61031952	144	dev_warn(dev, "unable to guarantee persistence of writes\n");
9e853f23	145
708ab62b CH	146	if (!devm_request_mem_region(dev, pmem->phys_addr, pmem->size,
708ab62b CH	147	dev_name(dev))) {
9f53f9fa DW	148	dev_warn(dev, "could not reserve region [0x%pa:0x%zx]\n",
9f53f9fa DW	149	&pmem->phys_addr, pmem->size);
8c2f7e86	150	return ERR_PTR(-EBUSY);
9e853f23 RZ	151	}
9e853f23 RZ	152
004f1afb DW	153	if (pmem_should_map_pages(dev)) {
	154	void *addr = devm_memremap_pages(dev, res);
	155
	156	if (IS_ERR(addr))
	157	return addr;
	158	pmem->virt_addr = (void __pmem *) addr;
	159	} else {
	160	pmem->virt_addr = memremap_pmem(dev, pmem->phys_addr,
	161	pmem->size);
	162	if (!pmem->virt_addr)
	163	return ERR_PTR(-ENXIO);
8c2f7e86 DW	164	}
	165
	166	return pmem;
	167	}
	168
	169	static void pmem_detach_disk(struct pmem_device *pmem)
	170	{
32ab0a3f DW	171	if (!pmem->pmem_disk)
	172	return;
	173
8c2f7e86 DW	174	del_gendisk(pmem->pmem_disk);
	175	put_disk(pmem->pmem_disk);
	176	blk_cleanup_queue(pmem->pmem_queue);
	177	}
	178
32ab0a3f DW	179	static int pmem_attach_disk(struct device *dev,
32ab0a3f DW	180	struct nd_namespace_common ndns, struct pmem_device pmem)
8c2f7e86	181	{
8c2f7e86	182	struct gendisk *disk;
9e853f23 RZ	183
	184	pmem->pmem_queue = blk_alloc_queue(GFP_KERNEL);
	185	if (!pmem->pmem_queue)
8c2f7e86	186	return -ENOMEM;
9e853f23 RZ	187
9e853f23 RZ	188	blk_queue_make_request(pmem->pmem_queue, pmem_make_request);
6b47496a	189	blk_queue_physical_block_size(pmem->pmem_queue, PAGE_SIZE);
43d3fa3a	190	blk_queue_max_hw_sectors(pmem->pmem_queue, UINT_MAX);
9e853f23	191	blk_queue_bounce_limit(pmem->pmem_queue, BLK_BOUNCE_ANY);
0f51c4fa	192	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, pmem->pmem_queue);
9e853f23	193
9f53f9fa	194	disk = alloc_disk(0);
8c2f7e86 DW	195	if (!disk) {
	196	blk_cleanup_queue(pmem->pmem_queue);
	197	return -ENOMEM;
	198	}
9e853f23	199
9e853f23	200	disk->major = pmem_major;
9f53f9fa	201	disk->first_minor = 0;
9e853f23 RZ	202	disk->fops = &pmem_fops;
	203	disk->private_data = pmem;
	204	disk->queue = pmem->pmem_queue;
	205	disk->flags = GENHD_FL_EXT_DEVT;
5212e11f	206	nvdimm_namespace_disk_name(ndns, disk->disk_name);
32ab0a3f DW	207	disk->driverfs_dev = dev;
32ab0a3f DW	208	set_capacity(disk, (pmem->size - pmem->data_offset) / 512);
9e853f23 RZ	209	pmem->pmem_disk = disk;
	210
	211	add_disk(disk);
58138820	212	revalidate_disk(disk);
9e853f23	213
8c2f7e86 DW	214	return 0;
8c2f7e86 DW	215	}
9e853f23	216
8c2f7e86 DW	217	static int pmem_rw_bytes(struct nd_namespace_common *ndns,
	218	resource_size_t offset, void *buf, size_t size, int rw)
	219	{
	220	struct pmem_device *pmem = dev_get_drvdata(ndns->claim);
	221
	222	if (unlikely(offset + size > pmem->size)) {
	223	dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n");
	224	return -EFAULT;
	225	}
	226
	227	if (rw == READ)
61031952 RZ	228	memcpy_from_pmem(buf, pmem->virt_addr + offset, size);
	229	else {
	230	memcpy_to_pmem(pmem->virt_addr + offset, buf, size);
	231	wmb_pmem();
	232	}
8c2f7e86 DW	233
	234	return 0;
	235	}
	236
32ab0a3f DW	237	static int nd_pfn_init(struct nd_pfn *nd_pfn)
	238	{
	239	struct nd_pfn_sb pfn_sb = kzalloc(sizeof(pfn_sb), GFP_KERNEL);
	240	struct pmem_device *pmem = dev_get_drvdata(&nd_pfn->dev);
	241	struct nd_namespace_common *ndns = nd_pfn->ndns;
	242	struct nd_region *nd_region;
	243	unsigned long npfns;
	244	phys_addr_t offset;
	245	u64 checksum;
	246	int rc;
	247
	248	if (!pfn_sb)
	249	return -ENOMEM;
	250
	251	nd_pfn->pfn_sb = pfn_sb;
	252	rc = nd_pfn_validate(nd_pfn);
	253	if (rc == 0 \|\| rc == -EBUSY)
	254	return rc;
	255
	256	/* section alignment for simple hotplug */
	257	if (nvdimm_namespace_capacity(ndns) < ND_PFN_ALIGN
	258	\|\| pmem->phys_addr & ND_PFN_MASK)
	259	return -ENODEV;
	260
	261	nd_region = to_nd_region(nd_pfn->dev.parent);
	262	if (nd_region->ro) {
	263	dev_info(&nd_pfn->dev,
	264	"%s is read-only, unable to init metadata\n",
	265	dev_name(&nd_region->dev));
	266	goto err;
	267	}
	268
	269	memset(pfn_sb, 0, sizeof(*pfn_sb));
	270	npfns = (pmem->size - SZ_8K) / SZ_4K;
	271	/*
	272	* Note, we use 64 here for the standard size of struct page,
	273	* debugging options may cause it to be larger in which case the
	274	* implementation will limit the pfns advertised through
	275	* ->direct_access() to those that are included in the memmap.
	276	*/
	277	if (nd_pfn->mode == PFN_MODE_PMEM)
	278	offset = ALIGN(SZ_8K + 64 * npfns, PMD_SIZE);
	279	else if (nd_pfn->mode == PFN_MODE_RAM)
	280	offset = SZ_8K;
	281	else
	282	goto err;
	283
	284	npfns = (pmem->size - offset) / SZ_4K;
	285	pfn_sb->mode = cpu_to_le32(nd_pfn->mode);
	286	pfn_sb->dataoff = cpu_to_le64(offset);
	287	pfn_sb->npfns = cpu_to_le64(npfns);
	288	memcpy(pfn_sb->signature, PFN_SIG, PFN_SIG_LEN);
	289	memcpy(pfn_sb->uuid, nd_pfn->uuid, 16);
	290	pfn_sb->version_major = cpu_to_le16(1);
	291	checksum = nd_sb_checksum((struct nd_gen_sb *) pfn_sb);
	292	pfn_sb->checksum = cpu_to_le64(checksum);
	293
	294	rc = nvdimm_write_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb));
	295	if (rc)
	296	goto err;
	297
	298	return 0;
	299	err:
	300	nd_pfn->pfn_sb = NULL;
301	kfree(pfn_sb);
302	return -ENXIO;
303	}
304
305	static int nvdimm_namespace_detach_pfn(struct nd_namespace_common *ndns)
306	{
307	struct nd_pfn *nd_pfn = to_nd_pfn(ndns->claim);
308	struct pmem_device *pmem;
309
310	/* free pmem disk */
311	pmem = dev_get_drvdata(&nd_pfn->dev);
312	pmem_detach_disk(pmem);
313
314	/* release nd_pfn resources */
315	kfree(nd_pfn->pfn_sb);
316	nd_pfn->pfn_sb = NULL;
317
318	return 0;
319	}
320
321	static int nvdimm_namespace_attach_pfn(struct nd_namespace_common *ndns)
9e853f23	322	{
32ab0a3f DW	323	struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
	324	struct nd_pfn *nd_pfn = to_nd_pfn(ndns->claim);
	325	struct device *dev = &nd_pfn->dev;
	326	struct vmem_altmap *altmap;
	327	struct nd_region *nd_region;
	328	struct nd_pfn_sb *pfn_sb;
	329	struct pmem_device *pmem;
	330	phys_addr_t offset;
	331	int rc;
	332
	333	if (!nd_pfn->uuid \|\| !nd_pfn->ndns)
	334	return -ENODEV;
	335
	336	nd_region = to_nd_region(dev->parent);
	337	rc = nd_pfn_init(nd_pfn);
	338	if (rc)
	339	return rc;
	340
	341	if (PAGE_SIZE != SZ_4K) {
	342	dev_err(dev, "only supported on systems with 4K PAGE_SIZE\n");
	343	return -ENXIO;
	344	}
	345	if (nsio->res.start & ND_PFN_MASK) {
	346	dev_err(dev, "%s not memory hotplug section aligned\n",
	347	dev_name(&ndns->dev));
	348	return -ENXIO;
	349	}
	350
	351	pfn_sb = nd_pfn->pfn_sb;
	352	offset = le64_to_cpu(pfn_sb->dataoff);
	353	nd_pfn->mode = le32_to_cpu(nd_pfn->pfn_sb->mode);
	354	if (nd_pfn->mode == PFN_MODE_RAM) {
	355	if (offset != SZ_8K)
	356	return -EINVAL;
	357	nd_pfn->npfns = le64_to_cpu(pfn_sb->npfns);
	358	altmap = NULL;
	359	} else {
	360	rc = -ENXIO;
	361	goto err;
	362	}
	363
	364	/* establish pfn range for lookup, and switch to direct map */
	365	pmem = dev_get_drvdata(dev);
	366	memunmap_pmem(dev, pmem->virt_addr);
	367	pmem->virt_addr = (void __pmem *)devm_memremap_pages(dev, &nsio->res);
	368	if (IS_ERR(pmem->virt_addr)) {
	369	rc = PTR_ERR(pmem->virt_addr);
	370	goto err;
	371	}
	372
	373	/* attach pmem disk in "pfn-mode" */
	374	pmem->data_offset = offset;
	375	rc = pmem_attach_disk(dev, ndns, pmem);
	376	if (rc)
	377	goto err;
	378
	379	return rc;
	380	err:
	381	nvdimm_namespace_detach_pfn(ndns);
	382	return rc;
9e853f23 RZ	383	}
9e853f23 RZ	384
9f53f9fa	385	static int nd_pmem_probe(struct device *dev)
9e853f23	386	{
9f53f9fa	387	struct nd_region *nd_region = to_nd_region(dev->parent);
8c2f7e86 DW	388	struct nd_namespace_common *ndns;
8c2f7e86 DW	389	struct nd_namespace_io *nsio;
9e853f23	390	struct pmem_device *pmem;
9e853f23	391
8c2f7e86 DW	392	ndns = nvdimm_namespace_common_probe(dev);
	393	if (IS_ERR(ndns))
	394	return PTR_ERR(ndns);
bf9bccc1	395
8c2f7e86	396	nsio = to_nd_namespace_io(&ndns->dev);
9f53f9fa	397	pmem = pmem_alloc(dev, &nsio->res, nd_region->id);
9e853f23 RZ	398	if (IS_ERR(pmem))
	399	return PTR_ERR(pmem);
	400
32ab0a3f	401	pmem->ndns = ndns;
9f53f9fa	402	dev_set_drvdata(dev, pmem);
8c2f7e86	403	ndns->rw_bytes = pmem_rw_bytes;
708ab62b	404
8c2f7e86	405	if (is_nd_btt(dev))
708ab62b CH	406	return nvdimm_namespace_attach_btt(ndns);
708ab62b CH	407
32ab0a3f DW	408	if (is_nd_pfn(dev))
	409	return nvdimm_namespace_attach_pfn(ndns);
	410
	411	if (nd_btt_probe(ndns, pmem) == 0) {
8c2f7e86	412	/* we'll come back as btt-pmem */
708ab62b	413	return -ENXIO;
32ab0a3f DW	414	}
	415
	416	if (nd_pfn_probe(ndns, pmem) == 0) {
	417	/* we'll come back as pfn-pmem */
	418	return -ENXIO;
	419	}
	420
	421	return pmem_attach_disk(dev, ndns, pmem);
9e853f23 RZ	422	}
9e853f23 RZ	423
9f53f9fa	424	static int nd_pmem_remove(struct device *dev)
9e853f23	425	{
9f53f9fa	426	struct pmem_device *pmem = dev_get_drvdata(dev);
9e853f23	427
8c2f7e86	428	if (is_nd_btt(dev))
32ab0a3f DW	429	nvdimm_namespace_detach_btt(pmem->ndns);
	430	else if (is_nd_pfn(dev))
	431	nvdimm_namespace_detach_pfn(pmem->ndns);
8c2f7e86 DW	432	else
8c2f7e86 DW	433	pmem_detach_disk(pmem);
8c2f7e86	434
9e853f23 RZ	435	return 0;
	436	}
	437
9f53f9fa DW	438	MODULE_ALIAS("pmem");
9f53f9fa DW	439	MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_IO);
bf9bccc1	440	MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_PMEM);
9f53f9fa DW	441	static struct nd_device_driver nd_pmem_driver = {
	442	.probe = nd_pmem_probe,
	443	.remove = nd_pmem_remove,
	444	.drv = {
	445	.name = "nd_pmem",
9e853f23	446	},
bf9bccc1	447	.type = ND_DRIVER_NAMESPACE_IO \| ND_DRIVER_NAMESPACE_PMEM,
9e853f23 RZ	448	};
	449
	450	static int __init pmem_init(void)
	451	{
	452	int error;
	453
	454	pmem_major = register_blkdev(0, "pmem");
	455	if (pmem_major < 0)
	456	return pmem_major;
	457
9f53f9fa DW	458	error = nd_driver_register(&nd_pmem_driver);
9f53f9fa DW	459	if (error) {
9e853f23	460	unregister_blkdev(pmem_major, "pmem");
9f53f9fa DW	461	return error;
	462	}
	463
	464	return 0;
9e853f23 RZ	465	}
	466	module_init(pmem_init);
	467
	468	static void pmem_exit(void)
	469	{
9f53f9fa	470	driver_unregister(&nd_pmem_driver.drv);
9e853f23 RZ	471	unregister_blkdev(pmem_major, "pmem");
	472	}
	473	module_exit(pmem_exit);
	474
	475	MODULE_AUTHOR("Ross Zwisler <ross.zwisler@linux.intel.com>");
	476	MODULE_LICENSE("GPL v2");