Merge tag 'libnvdimm-for-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull nvdimm and DAX updates from Vishal Verma:
 "This is mostly small cleanups and fixes, with the biggest change being
  the change to the DAX fault handler allowing it to return
  VM_FAULT_HWPOISON.

  Summary:

   - DAX fixes and cleanups including a use after free, extra
     references, and device unregistration, and a redundant variable.

   - Allow the DAX fault handler to return VM_FAULT_HWPOISON

   - A few libnvdimm cleanups such as making some functions and
     variables static where sufficient.

   - Add a few missing prototypes for wrapped functions in
     tools/testing/nvdimm"

* tag 'libnvdimm-for-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  dax: enable dax fault handler to report VM_FAULT_HWPOISON
  nvdimm: make security_show static
  nvdimm: make nd_class variable static
  dax/kmem: Pass valid argument to memory_group_register_static
  fsdax: remove redundant variable 'error'
  dax: Cleanup extra dax_region references
  dax: Introduce alloc_dev_dax_id()
  dax: Use device_unregister() in unregister_dax_mapping()
  dax: Fix dax_mapping_release() use after free
  tools/testing/nvdimm: Drop empty platform remove function
  libnvdimm: mark 'security_show' static again
  testing: nvdimm: add missing prototypes for wrapped functions
  dax: fix missing-prototype warnings

2 files changed, 15 insertions, 0 deletions

diff --git a/include/linux/dax.h b/include/linux/dax.h
index bf6258472e49..261944ec0887 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -261,6 +261,19 @@ static inline bool dax_mapping(struct address_space *mapping)
 	return mapping->host && IS_DAX(mapping->host);
 }
 
+/*
+ * Due to dax's memory and block duo personalities, hwpoison reporting
+ * takes into consideration which personality is presently visible.
+ * When dax acts like a block device, such as in block IO, an encounter of
+ * dax hwpoison is reported as -EIO.
+ * When dax acts like memory, such as in page fault, a detection of hwpoison
+ * is reported as -EHWPOISON which leads to VM_FAULT_HWPOISON.
+ */
+static inline int dax_mem2blk_err(int err)
+{
+	return (err == -EHWPOISON) ? -EIO : err;
+}
+
 #ifdef CONFIG_DEV_DAX_HMEM_DEVICES
 void hmem_register_resource(int target_nid, struct resource *r);
 #else
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 703ba8203da3..74f1be743ba2 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -3379,6 +3379,8 @@ static inline vm_fault_t vmf_error(int err)
 {
 	if (err == -ENOMEM)
 		return VM_FAULT_OOM;
+	else if (err == -EHWPOISON)
+		return VM_FAULT_HWPOISON;
 	return VM_FAULT_SIGBUS;
 }