Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 613 insertions, 0 deletions

diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
new file mode 100644
index 000000000..d6f981f6e
--- /dev/null
+++ b/drivers/nvdimm/pmem.c
@@ -0,0 +1,613 @@
+/*
+ * 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/set_memory.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/badblocks.h>
+#include <linux/memremap.h>
+#include <linux/vmalloc.h>
+#include <linux/blk-mq.h>
+#include <linux/pfn_t.h>
+#include <linux/slab.h>
+#include <linux/uio.h>
+#include <linux/dax.h>
+#include <linux/nd.h>
+#include <linux/backing-dev.h>
+#include "pmem.h"
+#include "pfn.h"
+#include "nd.h"
+#include "nd-core.h"
+
+static struct device *to_dev(struct pmem_device *pmem)
+{
+	/*
+	 * nvdimm bus services need a 'dev' parameter, and we record the device
+	 * at init in bb.dev.
+	 */
+	return pmem->bb.dev;
+}
+
+static struct nd_region *to_region(struct pmem_device *pmem)
+{
+	return to_nd_region(to_dev(pmem)->parent);
+}
+
+static void hwpoison_clear(struct pmem_device *pmem,
+		phys_addr_t phys, unsigned int len)
+{
+	unsigned long pfn_start, pfn_end, pfn;
+
+	/* only pmem in the linear map supports HWPoison */
+	if (is_vmalloc_addr(pmem->virt_addr))
+		return;
+
+	pfn_start = PHYS_PFN(phys);
+	pfn_end = pfn_start + PHYS_PFN(len);
+	for (pfn = pfn_start; pfn < pfn_end; pfn++) {
+		struct page *page = pfn_to_page(pfn);
+
+		/*
+		 * Note, no need to hold a get_dev_pagemap() reference
+		 * here since we're in the driver I/O path and
+		 * outstanding I/O requests pin the dev_pagemap.
+		 */
+		if (test_and_clear_pmem_poison(page))
+			clear_mce_nospec(pfn);
+	}
+}
+
+static blk_status_t pmem_clear_poison(struct pmem_device *pmem,
+		phys_addr_t offset, unsigned int len)
+{
+	struct device *dev = to_dev(pmem);
+	sector_t sector;
+	long cleared;
+	blk_status_t rc = BLK_STS_OK;
+
+	sector = (offset - pmem->data_offset) / 512;
+
+	cleared = nvdimm_clear_poison(dev, pmem->phys_addr + offset, len);
+	if (cleared < len)
+		rc = BLK_STS_IOERR;
+	if (cleared > 0 && cleared / 512) {
+		hwpoison_clear(pmem, pmem->phys_addr + offset, cleared);
+		cleared /= 512;
+		dev_dbg(dev, "%#llx clear %ld sector%s\n",
+				(unsigned long long) sector, cleared,
+				cleared > 1 ? "s" : "");
+		badblocks_clear(&pmem->bb, sector, cleared);
+		if (pmem->bb_state)
+			sysfs_notify_dirent(pmem->bb_state);
+	}
+
+	arch_invalidate_pmem(pmem->virt_addr + offset, len);
+
+	return rc;
+}
+
+static void write_pmem(void *pmem_addr, struct page *page,
+		unsigned int off, unsigned int len)
+{
+	unsigned int chunk;
+	void *mem;
+
+	while (len) {
+		mem = kmap_atomic(page);
+		chunk = min_t(unsigned int, len, PAGE_SIZE - off);
+		memcpy_flushcache(pmem_addr, mem + off, chunk);
+		kunmap_atomic(mem);
+		len -= chunk;
+		off = 0;
+		page++;
+		pmem_addr += chunk;
+	}
+}
+
+static blk_status_t read_pmem(struct page *page, unsigned int off,
+		void *pmem_addr, unsigned int len)
+{
+	unsigned int chunk;
+	unsigned long rem;
+	void *mem;
+
+	while (len) {
+		mem = kmap_atomic(page);
+		chunk = min_t(unsigned int, len, PAGE_SIZE - off);
+		rem = memcpy_mcsafe(mem + off, pmem_addr, chunk);
+		kunmap_atomic(mem);
+		if (rem)
+			return BLK_STS_IOERR;
+		len -= chunk;
+		off = 0;
+		page++;
+		pmem_addr += chunk;
+	}
+	return BLK_STS_OK;
+}
+
+static blk_status_t pmem_do_bvec(struct pmem_device *pmem, struct page *page,
+			unsigned int len, unsigned int off, unsigned int op,
+			sector_t sector)
+{
+	blk_status_t rc = BLK_STS_OK;
+	bool bad_pmem = false;
+	phys_addr_t pmem_off = sector * 512 + pmem->data_offset;
+	void *pmem_addr = pmem->virt_addr + pmem_off;
+
+	if (unlikely(is_bad_pmem(&pmem->bb, sector, len)))
+		bad_pmem = true;
+
+	if (!op_is_write(op)) {
+		if (unlikely(bad_pmem))
+			rc = BLK_STS_IOERR;
+		else {
+			rc = read_pmem(page, off, pmem_addr, len);
+			flush_dcache_page(page);
+		}
+	} else {
+		/*
+		 * Note that we write the data both before and after
+		 * clearing poison.  The write before clear poison
+		 * handles situations where the latest written data is
+		 * preserved and the clear poison operation simply marks
+		 * the address range as valid without changing the data.
+		 * In this case application software can assume that an
+		 * interrupted write will either return the new good
+		 * data or an error.
+		 *
+		 * However, if pmem_clear_poison() leaves the data in an
+		 * indeterminate state we need to perform the write
+		 * after clear poison.
+		 */
+		flush_dcache_page(page);
+		write_pmem(pmem_addr, page, off, len);
+		if (unlikely(bad_pmem)) {
+			rc = pmem_clear_poison(pmem, pmem_off, len);
+			write_pmem(pmem_addr, page, off, len);
+		}
+	}
+
+	return rc;
+}
+
+static blk_qc_t pmem_make_request(struct request_queue *q, struct bio *bio)
+{
+	blk_status_t rc = 0;
+	bool do_acct;
+	unsigned long start;
+	struct bio_vec bvec;
+	struct bvec_iter iter;
+	struct pmem_device *pmem = q->queuedata;
+	struct nd_region *nd_region = to_region(pmem);
+
+	if (bio->bi_opf & REQ_PREFLUSH)
+		nvdimm_flush(nd_region);
+
+	do_acct = nd_iostat_start(bio, &start);
+	bio_for_each_segment(bvec, bio, iter) {
+		rc = pmem_do_bvec(pmem, bvec.bv_page, bvec.bv_len,
+				bvec.bv_offset, bio_op(bio), iter.bi_sector);
+		if (rc) {
+			bio->bi_status = rc;
+			break;
+		}
+	}
+	if (do_acct)
+		nd_iostat_end(bio, start);
+
+	if (bio->bi_opf & REQ_FUA)
+		nvdimm_flush(nd_region);
+
+	bio_endio(bio);
+	return BLK_QC_T_NONE;
+}
+
+static int pmem_rw_page(struct block_device *bdev, sector_t sector,
+		       struct page *page, unsigned int op)
+{
+	struct pmem_device *pmem = bdev->bd_queue->queuedata;
+	blk_status_t rc;
+
+	rc = pmem_do_bvec(pmem, page, hpage_nr_pages(page) * PAGE_SIZE,
+			  0, op, sector);
+
+	/*
+	 * The ->rw_page interface is subtle and tricky.  The core
+	 * retries on any error, so we can only invoke page_endio() in
+	 * the successful completion case.  Otherwise, we'll see crashes
+	 * caused by double completion.
+	 */
+	if (rc == 0)
+		page_endio(page, op_is_write(op), 0);
+
+	return blk_status_to_errno(rc);
+}
+
+/* see "strong" declaration in tools/testing/nvdimm/pmem-dax.c */
+__weak long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
+		long nr_pages, void **kaddr, pfn_t *pfn)
+{
+	resource_size_t offset = PFN_PHYS(pgoff) + pmem->data_offset;
+
+	if (unlikely(is_bad_pmem(&pmem->bb, PFN_PHYS(pgoff) / 512,
+					PFN_PHYS(nr_pages))))
+		return -EIO;
+
+	if (kaddr)
+		*kaddr = pmem->virt_addr + offset;
+	if (pfn)
+		*pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
+
+	/*
+	 * If badblocks are present, limit known good range to the
+	 * requested range.
+	 */
+	if (unlikely(pmem->bb.count))
+		return nr_pages;
+	return PHYS_PFN(pmem->size - pmem->pfn_pad - offset);
+}
+
+static const struct block_device_operations pmem_fops = {
+	.owner =		THIS_MODULE,
+	.rw_page =		pmem_rw_page,
+	.revalidate_disk =	nvdimm_revalidate_disk,
+};
+
+static long pmem_dax_direct_access(struct dax_device *dax_dev,
+		pgoff_t pgoff, long nr_pages, void **kaddr, pfn_t *pfn)
+{
+	struct pmem_device *pmem = dax_get_private(dax_dev);
+
+	return __pmem_direct_access(pmem, pgoff, nr_pages, kaddr, pfn);
+}
+
+/*
+ * Use the 'no check' versions of copy_from_iter_flushcache() and
+ * copy_to_iter_mcsafe() to bypass HARDENED_USERCOPY overhead. Bounds
+ * checking, both file offset and device offset, is handled by
+ * dax_iomap_actor()
+ */
+static size_t pmem_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff,
+		void *addr, size_t bytes, struct iov_iter *i)
+{
+	return _copy_from_iter_flushcache(addr, bytes, i);
+}
+
+static size_t pmem_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff,
+		void *addr, size_t bytes, struct iov_iter *i)
+{
+	return _copy_to_iter_mcsafe(addr, bytes, i);
+}
+
+static const struct dax_operations pmem_dax_ops = {
+	.direct_access = pmem_dax_direct_access,
+	.copy_from_iter = pmem_copy_from_iter,
+	.copy_to_iter = pmem_copy_to_iter,
+};
+
+static const struct attribute_group *pmem_attribute_groups[] = {
+	&dax_attribute_group,
+	NULL,
+};
+
+static void pmem_release_queue(void *q)
+{
+	blk_cleanup_queue(q);
+}
+
+static void pmem_freeze_queue(struct percpu_ref *ref)
+{
+	struct request_queue *q;
+
+	q = container_of(ref, typeof(*q), q_usage_counter);
+	blk_freeze_queue_start(q);
+}
+
+static void pmem_release_disk(void *__pmem)
+{
+	struct pmem_device *pmem = __pmem;
+
+	kill_dax(pmem->dax_dev);
+	put_dax(pmem->dax_dev);
+	del_gendisk(pmem->disk);
+	put_disk(pmem->disk);
+}
+
+static void pmem_release_pgmap_ops(void *__pgmap)
+{
+	dev_pagemap_put_ops();
+}
+
+static void fsdax_pagefree(struct page *page, void *data)
+{
+	wake_up_var(&page->_refcount);
+}
+
+static int setup_pagemap_fsdax(struct device *dev, struct dev_pagemap *pgmap)
+{
+	dev_pagemap_get_ops();
+	if (devm_add_action_or_reset(dev, pmem_release_pgmap_ops, pgmap))
+		return -ENOMEM;
+	pgmap->type = MEMORY_DEVICE_FS_DAX;
+	pgmap->page_free = fsdax_pagefree;
+
+	return 0;
+}
+
+static int pmem_attach_disk(struct device *dev,
+		struct nd_namespace_common *ndns)
+{
+	struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
+	struct nd_region *nd_region = to_nd_region(dev->parent);
+	int nid = dev_to_node(dev), fua;
+	struct resource *res = &nsio->res;
+	struct resource bb_res;
+	struct nd_pfn *nd_pfn = NULL;
+	struct dax_device *dax_dev;
+	struct nd_pfn_sb *pfn_sb;
+	struct pmem_device *pmem;
+	struct request_queue *q;
+	struct device *gendev;
+	struct gendisk *disk;
+	void *addr;
+	int rc;
+
+	pmem = devm_kzalloc(dev, sizeof(*pmem), GFP_KERNEL);
+	if (!pmem)
+		return -ENOMEM;
+
+	/* while nsio_rw_bytes is active, parse a pfn info block if present */
+	if (is_nd_pfn(dev)) {
+		nd_pfn = to_nd_pfn(dev);
+		rc = nvdimm_setup_pfn(nd_pfn, &pmem->pgmap);
+		if (rc)
+			return rc;
+	}
+
+	/* we're attaching a block device, disable raw namespace access */
+	devm_nsio_disable(dev, nsio);
+
+	dev_set_drvdata(dev, pmem);
+	pmem->phys_addr = res->start;
+	pmem->size = resource_size(res);
+	fua = nvdimm_has_flush(nd_region);
+	if (!IS_ENABLED(CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE) || fua < 0) {
+		dev_warn(dev, "unable to guarantee persistence of writes\n");
+		fua = 0;
+	}
+
+	if (!devm_request_mem_region(dev, res->start, resource_size(res),
+				dev_name(&ndns->dev))) {
+		dev_warn(dev, "could not reserve region %pR\n", res);
+		return -EBUSY;
+	}
+
+	q = blk_alloc_queue_node(GFP_KERNEL, dev_to_node(dev), NULL);
+	if (!q)
+		return -ENOMEM;
+
+	if (devm_add_action_or_reset(dev, pmem_release_queue, q))
+		return -ENOMEM;
+
+	pmem->pfn_flags = PFN_DEV;
+	pmem->pgmap.ref = &q->q_usage_counter;
+	pmem->pgmap.kill = pmem_freeze_queue;
+	if (is_nd_pfn(dev)) {
+		if (setup_pagemap_fsdax(dev, &pmem->pgmap))
+			return -ENOMEM;
+		addr = devm_memremap_pages(dev, &pmem->pgmap);
+		pfn_sb = nd_pfn->pfn_sb;
+		pmem->data_offset = le64_to_cpu(pfn_sb->dataoff);
+		pmem->pfn_pad = resource_size(res) -
+			resource_size(&pmem->pgmap.res);
+		pmem->pfn_flags |= PFN_MAP;
+		memcpy(&bb_res, &pmem->pgmap.res, sizeof(bb_res));
+		bb_res.start += pmem->data_offset;
+	} else if (pmem_should_map_pages(dev)) {
+		memcpy(&pmem->pgmap.res, &nsio->res, sizeof(pmem->pgmap.res));
+		pmem->pgmap.altmap_valid = false;
+		if (setup_pagemap_fsdax(dev, &pmem->pgmap))
+			return -ENOMEM;
+		addr = devm_memremap_pages(dev, &pmem->pgmap);
+		pmem->pfn_flags |= PFN_MAP;
+		memcpy(&bb_res, &pmem->pgmap.res, sizeof(bb_res));
+	} else {
+		addr = devm_memremap(dev, pmem->phys_addr,
+				pmem->size, ARCH_MEMREMAP_PMEM);
+		memcpy(&bb_res, &nsio->res, sizeof(bb_res));
+	}
+
+	if (IS_ERR(addr))
+		return PTR_ERR(addr);
+	pmem->virt_addr = addr;
+
+	blk_queue_write_cache(q, true, fua);
+	blk_queue_make_request(q, pmem_make_request);
+	blk_queue_physical_block_size(q, PAGE_SIZE);
+	blk_queue_logical_block_size(q, pmem_sector_size(ndns));
+	blk_queue_max_hw_sectors(q, UINT_MAX);
+	blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
+	if (pmem->pfn_flags & PFN_MAP)
+		blk_queue_flag_set(QUEUE_FLAG_DAX, q);
+	q->queuedata = pmem;
+
+	disk = alloc_disk_node(0, nid);
+	if (!disk)
+		return -ENOMEM;
+	pmem->disk = disk;
+
+	disk->fops		= &pmem_fops;
+	disk->queue		= q;
+	disk->flags		= GENHD_FL_EXT_DEVT;
+	disk->queue->backing_dev_info->capabilities |= BDI_CAP_SYNCHRONOUS_IO;
+	nvdimm_namespace_disk_name(ndns, disk->disk_name);
+	set_capacity(disk, (pmem->size - pmem->pfn_pad - pmem->data_offset)
+			/ 512);
+	if (devm_init_badblocks(dev, &pmem->bb))
+		return -ENOMEM;
+	nvdimm_badblocks_populate(nd_region, &pmem->bb, &bb_res);
+	disk->bb = &pmem->bb;
+
+	dax_dev = alloc_dax(pmem, disk->disk_name, &pmem_dax_ops);
+	if (!dax_dev) {
+		put_disk(disk);
+		return -ENOMEM;
+	}
+	dax_write_cache(dax_dev, nvdimm_has_cache(nd_region));
+	pmem->dax_dev = dax_dev;
+
+	gendev = disk_to_dev(disk);
+	gendev->groups = pmem_attribute_groups;
+
+	device_add_disk(dev, disk, NULL);
+	if (devm_add_action_or_reset(dev, pmem_release_disk, pmem))
+		return -ENOMEM;
+
+	revalidate_disk(disk);
+
+	pmem->bb_state = sysfs_get_dirent(disk_to_dev(disk)->kobj.sd,
+					  "badblocks");
+	if (!pmem->bb_state)
+		dev_warn(dev, "'badblocks' notification disabled\n");
+
+	return 0;
+}
+
+static int nd_pmem_probe(struct device *dev)
+{
+	struct nd_namespace_common *ndns;
+
+	ndns = nvdimm_namespace_common_probe(dev);
+	if (IS_ERR(ndns))
+		return PTR_ERR(ndns);
+
+	if (devm_nsio_enable(dev, to_nd_namespace_io(&ndns->dev)))
+		return -ENXIO;
+
+	if (is_nd_btt(dev))
+		return nvdimm_namespace_attach_btt(ndns);
+
+	if (is_nd_pfn(dev))
+		return pmem_attach_disk(dev, ndns);
+
+	/* if we find a valid info-block we'll come back as that personality */
+	if (nd_btt_probe(dev, ndns) == 0 || nd_pfn_probe(dev, ndns) == 0
+			|| nd_dax_probe(dev, ndns) == 0)
+		return -ENXIO;
+
+	/* ...otherwise we're just a raw pmem device */
+	return pmem_attach_disk(dev, ndns);
+}
+
+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(to_nd_btt(dev));
+	else {
+		/*
+		 * Note, this assumes device_lock() context to not race
+		 * nd_pmem_notify()
+		 */
+		sysfs_put(pmem->bb_state);
+		pmem->bb_state = NULL;
+	}
+	nvdimm_flush(to_nd_region(dev->parent));
+
+	return 0;
+}
+
+static void nd_pmem_shutdown(struct device *dev)
+{
+	nvdimm_flush(to_nd_region(dev->parent));
+}
+
+static void nd_pmem_notify(struct device *dev, enum nvdimm_event event)
+{
+	struct nd_region *nd_region;
+	resource_size_t offset = 0, end_trunc = 0;
+	struct nd_namespace_common *ndns;
+	struct nd_namespace_io *nsio;
+	struct resource res;
+	struct badblocks *bb;
+	struct kernfs_node *bb_state;
+
+	if (event != NVDIMM_REVALIDATE_POISON)
+		return;
+
+	if (is_nd_btt(dev)) {
+		struct nd_btt *nd_btt = to_nd_btt(dev);
+
+		ndns = nd_btt->ndns;
+		nd_region = to_nd_region(ndns->dev.parent);
+		nsio = to_nd_namespace_io(&ndns->dev);
+		bb = &nsio->bb;
+		bb_state = NULL;
+	} else {
+		struct pmem_device *pmem = dev_get_drvdata(dev);
+
+		nd_region = to_region(pmem);
+		bb = &pmem->bb;
+		bb_state = pmem->bb_state;
+
+		if (is_nd_pfn(dev)) {
+			struct nd_pfn *nd_pfn = to_nd_pfn(dev);
+			struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
+
+			ndns = nd_pfn->ndns;
+			offset = pmem->data_offset +
+					__le32_to_cpu(pfn_sb->start_pad);
+			end_trunc = __le32_to_cpu(pfn_sb->end_trunc);
+		} else {
+			ndns = to_ndns(dev);
+		}
+
+		nsio = to_nd_namespace_io(&ndns->dev);
+	}
+
+	res.start = nsio->res.start + offset;
+	res.end = nsio->res.end - end_trunc;
+	nvdimm_badblocks_populate(nd_region, bb, &res);
+	if (bb_state)
+		sysfs_notify_dirent(bb_state);
+}
+
+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,
+	.notify = nd_pmem_notify,
+	.shutdown = nd_pmem_shutdown,
+	.drv = {
+		.name = "nd_pmem",
+	},
+	.type = ND_DRIVER_NAMESPACE_IO | ND_DRIVER_NAMESPACE_PMEM,
+};
+
+module_nd_driver(nd_pmem_driver);
+
+MODULE_AUTHOR("Ross Zwisler <ross.zwisler@linux.intel.com>");
+MODULE_LICENSE("GPL v2");