Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm fixes from Dan Williams:
 "A 4.16 regression fix, three fixes for -stable, and a cleanup fix:

   - During the merge window support for the new ACPI NVDIMM Platform
     Capabilities structure disabled support for "deep flush", a
     force-unit- access like mechanism for persistent memory. Restore
     that mechanism.

   - VFIO like RDMA is yet one more memory registration / pinning
     interface that is incompatible with Filesystem-DAX. Disable long
     term pins of Filesystem-DAX mappings via VFIO.

   - The Filesystem-DAX detection to prevent long terms pins mistakenly
     also disabled Device-DAX pins which are not subject to the same
     block- map collision concerns.

   - Similar to the setup path, softlockup warnings can trigger in the
     shutdown path for large persistent memory namespaces. Teach
     for_each_device_pfn() to perform cond_resched() in all cases.

   - Boaz noticed that the might_sleep() in dax_direct_access() is stale
     as of the v4.15 kernel.

  These have received a build success notification from the 0day robot,
  and the longterm pin fixes have appeared in -next. However, I recently
  rebased the tree to remove some other fixes that need to be reworked
  after review feedback.

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  memremap: fix softlockup reports at teardown
  libnvdimm: re-enable deep flush for pmem devices via fsync()
  vfio: disable filesystem-dax page pinning
  dax: fix vma_is_fsdax() helper
  dax: ->direct_access does not sleep anymore

1 files changed, 10 insertions, 5 deletions

diff --git a/kernel/memremap.c b/kernel/memremap.c
index 4849be5f9b3c..4dd4274cabe2 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -275,8 +275,15 @@ static unsigned long pfn_end(struct dev_pagemap *pgmap)
 	return (res->start + resource_size(res)) >> PAGE_SHIFT;
 }
 
+static unsigned long pfn_next(unsigned long pfn)
+{
+	if (pfn % 1024 == 0)
+		cond_resched();
+	return pfn + 1;
+}
+
 #define for_each_device_pfn(pfn, map) \
-	for (pfn = pfn_first(map); pfn < pfn_end(map); pfn++)
+	for (pfn = pfn_first(map); pfn < pfn_end(map); pfn = pfn_next(pfn))
 
 static void devm_memremap_pages_release(void *data)
 {
@@ -337,10 +344,10 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
 	resource_size_t align_start, align_size, align_end;
 	struct vmem_altmap *altmap = pgmap->altmap_valid ?
 			&pgmap->altmap : NULL;
+	struct resource *res = &pgmap->res;
 	unsigned long pfn, pgoff, order;
 	pgprot_t pgprot = PAGE_KERNEL;
-	int error, nid, is_ram, i = 0;
-	struct resource *res = &pgmap->res;
+	int error, nid, is_ram;
 
 	align_start = res->start & ~(SECTION_SIZE - 1);
 	align_size = ALIGN(res->start + resource_size(res), SECTION_SIZE)
@@ -409,8 +416,6 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
 		list_del(&page->lru);
 		page->pgmap = pgmap;
 		percpu_ref_get(pgmap->ref);
-		if (!(++i % 1024))
-			cond_resched();
 	}
 
 	devm_add_action(dev, devm_memremap_pages_release, pgmap);