Merge tag 'libnvdimm-for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:
 "The bulk of this has appeared in -next and independently received a
  build success notification from the kbuild robot.  The 'for-4.5/block-
  dax' topic branch was rebased over the weekend to drop the "block
  device end-of-life" rework that Al would like to see re-implemented
  with a notifier, and to address bug reports against the badblocks
  integration.

  There is pending feedback against "libnvdimm: Add a poison list and
  export badblocks" received last week.  Linda identified some localized
  fixups that we will handle incrementally.

  Summary:

   - Media error handling: The 'badblocks' implementation that
     originated in md-raid is up-levelled to a generic capability of a
     block device.  This initial implementation is limited to being
     consulted in the pmem block-i/o path.  Later, 'badblocks' will be
     consulted when creating dax mappings.

   - Raw block device dax: For virtualization and other cases that want
     large contiguous mappings of persistent memory, add the capability
     to dax-mmap a block device directly.

   - Increased /dev/mem restrictions: Add an option to treat all
     io-memory as IORESOURCE_EXCLUSIVE, i.e. disable /dev/mem access
     while a driver is actively using an address range.  This behavior
     is controlled via the new CONFIG_IO_STRICT_DEVMEM option and can be
     overridden by the existing "iomem=relaxed" kernel command line
     option.

   - Miscellaneous fixes include a 'pfn'-device huge page alignment fix,
     block device shutdown crash fix, and other small libnvdimm fixes"

* tag 'libnvdimm-for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (32 commits)
  block: kill disk_{check|set|clear|alloc}_badblocks
  libnvdimm, pmem: nvdimm_read_bytes() badblocks support
  pmem, dax: disable dax in the presence of bad blocks
  pmem: fail io-requests to known bad blocks
  libnvdimm: convert to statically allocated badblocks
  libnvdimm: don't fail init for full badblocks list
  block, badblocks: introduce devm_init_badblocks
  block: clarify badblocks lifetime
  badblocks: rename badblocks_free to badblocks_exit
  libnvdimm, pmem: move definition of nvdimm_namespace_add_poison to nd.h
  libnvdimm: Add a poison list and export badblocks
  nfit_test: Enable DSMs for all test NFITs
  md: convert to use the generic badblocks code
  block: Add badblock management for gendisks
  badblocks: Add core badblock management code
  block: fix del_gendisk() vs blkdev_ioctl crash
  block: enable dax for raw block devices
  block: introduce bdev_file_inode()
  restrict /dev/mem to idle io memory ranges
  arch: consolidate CONFIG_STRICT_DEVM in lib/Kconfig.debug
  ...

1 files changed, 169 insertions, 0 deletions

diff --git a/drivers/nvdimm/core.c b/drivers/nvdimm/core.c
index 82c49bb87055..2e2832b83c93 100644
--- a/drivers/nvdimm/core.c
+++ b/drivers/nvdimm/core.c
@@ -11,6 +11,7 @@
  * General Public License for more details.
  */
 #include <linux/libnvdimm.h>
+#include <linux/badblocks.h>
 #include <linux/export.h>
 #include <linux/module.h>
 #include <linux/blkdev.h>
@@ -325,6 +326,7 @@ struct nvdimm_bus *__nvdimm_bus_register(struct device *parent,
 	if (!nvdimm_bus)
 		return NULL;
 	INIT_LIST_HEAD(&nvdimm_bus->list);
+	INIT_LIST_HEAD(&nvdimm_bus->poison_list);
 	init_waitqueue_head(&nvdimm_bus->probe_wait);
 	nvdimm_bus->id = ida_simple_get(&nd_ida, 0, 0, GFP_KERNEL);
 	mutex_init(&nvdimm_bus->reconfig_mutex);
@@ -359,6 +361,172 @@ struct nvdimm_bus *__nvdimm_bus_register(struct device *parent,
 }
 EXPORT_SYMBOL_GPL(__nvdimm_bus_register);
 
+static void set_badblock(struct badblocks *bb, sector_t s, int num)
+{
+	dev_dbg(bb->dev, "Found a poison range (0x%llx, 0x%llx)\n",
+			(u64) s * 512, (u64) num * 512);
+	/* this isn't an error as the hardware will still throw an exception */
+	if (badblocks_set(bb, s, num, 1))
+		dev_info_once(bb->dev, "%s: failed for sector %llx\n",
+				__func__, (u64) s);
+}
+
+/**
+ * __add_badblock_range() - Convert a physical address range to bad sectors
+ * @bb:		badblocks instance to populate
+ * @ns_offset:	namespace offset where the error range begins (in bytes)
+ * @len:	number of bytes of poison to be added
+ *
+ * This assumes that the range provided with (ns_offset, len) is within
+ * the bounds of physical addresses for this namespace, i.e. lies in the
+ * interval [ns_start, ns_start + ns_size)
+ */
+static void __add_badblock_range(struct badblocks *bb, u64 ns_offset, u64 len)
+{
+	const unsigned int sector_size = 512;
+	sector_t start_sector;
+	u64 num_sectors;
+	u32 rem;
+
+	start_sector = div_u64(ns_offset, sector_size);
+	num_sectors = div_u64_rem(len, sector_size, &rem);
+	if (rem)
+		num_sectors++;
+
+	if (unlikely(num_sectors > (u64)INT_MAX)) {
+		u64 remaining = num_sectors;
+		sector_t s = start_sector;
+
+		while (remaining) {
+			int done = min_t(u64, remaining, INT_MAX);
+
+			set_badblock(bb, s, done);
+			remaining -= done;
+			s += done;
+		}
+	} else
+		set_badblock(bb, start_sector, num_sectors);
+}
+
+/**
+ * nvdimm_namespace_add_poison() - Convert a list of poison ranges to badblocks
+ * @ndns:	the namespace containing poison ranges
+ * @bb:		badblocks instance to populate
+ * @offset:	offset at the start of the namespace before 'sector 0'
+ *
+ * The poison list generated during NFIT initialization may contain multiple,
+ * possibly overlapping ranges in the SPA (System Physical Address) space.
+ * Compare each of these ranges to the namespace currently being initialized,
+ * and add badblocks to the gendisk for all matching sub-ranges
+ */
+void nvdimm_namespace_add_poison(struct nd_namespace_common *ndns,
+		struct badblocks *bb, resource_size_t offset)
+{
+	struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
+	struct nd_region *nd_region = to_nd_region(ndns->dev.parent);
+	struct nvdimm_bus *nvdimm_bus;
+	struct list_head *poison_list;
+	u64 ns_start, ns_end, ns_size;
+	struct nd_poison *pl;
+
+	ns_size = nvdimm_namespace_capacity(ndns) - offset;
+	ns_start = nsio->res.start + offset;
+	ns_end = nsio->res.end;
+
+	nvdimm_bus = to_nvdimm_bus(nd_region->dev.parent);
+	poison_list = &nvdimm_bus->poison_list;
+	if (list_empty(poison_list))
+		return;
+
+	list_for_each_entry(pl, poison_list, list) {
+		u64 pl_end = pl->start + pl->length - 1;
+
+		/* Discard intervals with no intersection */
+		if (pl_end < ns_start)
+			continue;
+		if (pl->start > ns_end)
+			continue;
+		/* Deal with any overlap after start of the namespace */
+		if (pl->start >= ns_start) {
+			u64 start = pl->start;
+			u64 len;
+
+			if (pl_end <= ns_end)
+				len = pl->length;
+			else
+				len = ns_start + ns_size - pl->start;
+			__add_badblock_range(bb, start - ns_start, len);
+			continue;
+		}
+		/* Deal with overlap for poison starting before the namespace */
+		if (pl->start < ns_start) {
+			u64 len;
+
+			if (pl_end < ns_end)
+				len = pl->start + pl->length - ns_start;
+			else
+				len = ns_size;
+			__add_badblock_range(bb, 0, len);
+		}
+	}
+}
+EXPORT_SYMBOL_GPL(nvdimm_namespace_add_poison);
+
+static int __add_poison(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length)
+{
+	struct nd_poison *pl;
+
+	pl = kzalloc(sizeof(*pl), GFP_KERNEL);
+	if (!pl)
+		return -ENOMEM;
+
+	pl->start = addr;
+	pl->length = length;
+	list_add_tail(&pl->list, &nvdimm_bus->poison_list);
+
+	return 0;
+}
+
+int nvdimm_bus_add_poison(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length)
+{
+	struct nd_poison *pl;
+
+	if (list_empty(&nvdimm_bus->poison_list))
+		return __add_poison(nvdimm_bus, addr, length);
+
+	/*
+	 * There is a chance this is a duplicate, check for those first.
+	 * This will be the common case as ARS_STATUS returns all known
+	 * errors in the SPA space, and we can't query it per region
+	 */
+	list_for_each_entry(pl, &nvdimm_bus->poison_list, list)
+		if (pl->start == addr) {
+			/* If length has changed, update this list entry */
+			if (pl->length != length)
+				pl->length = length;
+			return 0;
+		}
+
+	/*
+	 * If not a duplicate or a simple length update, add the entry as is,
+	 * as any overlapping ranges will get resolved when the list is consumed
+	 * and converted to badblocks
+	 */
+	return __add_poison(nvdimm_bus, addr, length);
+}
+EXPORT_SYMBOL_GPL(nvdimm_bus_add_poison);
+
+static void free_poison_list(struct list_head *poison_list)
+{
+	struct nd_poison *pl, *next;
+
+	list_for_each_entry_safe(pl, next, poison_list, list) {
+		list_del(&pl->list);
+		kfree(pl);
+	}
+	list_del_init(poison_list);
+}
+
 static int child_unregister(struct device *dev, void *data)
 {
 	/*
@@ -385,6 +553,7 @@ void nvdimm_bus_unregister(struct nvdimm_bus *nvdimm_bus)
 
 	nd_synchronize();
 	device_for_each_child(&nvdimm_bus->dev, NULL, child_unregister);
+	free_poison_list(&nvdimm_bus->poison_list);
 	nvdimm_bus_destroy_ndctl(nvdimm_bus);
 
 	device_unregister(&nvdimm_bus->dev);