Merge tag 'libnvdimm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:

 - Replace pcommit with ADR / directed-flushing.

   The pcommit instruction, which has not shipped on any product, is
   deprecated.  Instead, the requirement is that platforms implement
   either ADR, or provide one or more flush addresses per nvdimm.

   ADR (Asynchronous DRAM Refresh) flushes data in posted write buffers
   to the memory controller on a power-fail event.

   Flush addresses are defined in ACPI 6.x as an NVDIMM Firmware
   Interface Table (NFIT) sub-structure: "Flush Hint Address Structure".
   A flush hint is an mmio address that when written and fenced assures
   that all previous posted writes targeting a given dimm have been
   flushed to media.

 - On-demand ARS (address range scrub).

   Linux uses the results of the ACPI ARS commands to track bad blocks
   in pmem devices.  When latent errors are detected we re-scrub the
   media to refresh the bad block list, userspace can also request a
   re-scrub at any time.

 - Support for the Microsoft DSM (device specific method) command
   format.

 - Support for EDK2/OVMF virtual disk device memory ranges.

 - Various fixes and cleanups across the subsystem.

* tag 'libnvdimm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (41 commits)
  libnvdimm-btt: Delete an unnecessary check before the function call "__nd_device_register"
  nfit: do an ARS scrub on hitting a latent media error
  nfit: move to nfit/ sub-directory
  nfit, libnvdimm: allow an ARS scrub to be triggered on demand
  libnvdimm: register nvdimm_bus devices with an nd_bus driver
  pmem: clarify a debug print in pmem_clear_poison
  x86/insn: remove pcommit
  Revert "KVM: x86: add pcommit support"
  nfit, tools/testing/nvdimm/: unify shutdown paths
  libnvdimm: move ->module to struct nvdimm_bus_descriptor
  nfit: cleanup acpi_nfit_init calling convention
  nfit: fix _FIT evaluation memory leak + use after free
  tools/testing/nvdimm: add manufacturing_{date|location} dimm properties
  tools/testing/nvdimm: add virtual ramdisk range
  acpi, nfit: treat virtual ramdisk SPA as pmem region
  pmem: kill __pmem address space
  pmem: kill wmb_pmem()
  libnvdimm, pmem: use nvdimm_flush() for namespace I/O writes
  fs/dax: remove wmb_pmem()
  libnvdimm, pmem: flush posted-write queues on shutdown
  ...

1 files changed, 21 insertions, 96 deletions

diff --git a/include/linux/pmem.h b/include/linux/pmem.h
index 57d146fe44dd..e856c2cb0fe8 100644
--- a/include/linux/pmem.h
+++ b/include/linux/pmem.h
@@ -26,47 +26,35 @@
  * calling these symbols with arch_has_pmem_api() and redirect to the
  * implementation in asm/pmem.h.
  */
-static inline bool __arch_has_wmb_pmem(void)
-{
-	return false;
-}
-
-static inline void arch_wmb_pmem(void)
-{
-	BUG();
-}
-
-static inline void arch_memcpy_to_pmem(void __pmem *dst, const void *src,
-		size_t n)
+static inline void arch_memcpy_to_pmem(void *dst, const void *src, size_t n)
 {
 	BUG();
 }
 
-static inline int arch_memcpy_from_pmem(void *dst, const void __pmem *src,
-		size_t n)
+static inline int arch_memcpy_from_pmem(void *dst, const void *src, size_t n)
 {
 	BUG();
 	return -EFAULT;
 }
 
-static inline size_t arch_copy_from_iter_pmem(void __pmem *addr, size_t bytes,
+static inline size_t arch_copy_from_iter_pmem(void *addr, size_t bytes,
 		struct iov_iter *i)
 {
 	BUG();
 	return 0;
 }
 
-static inline void arch_clear_pmem(void __pmem *addr, size_t size)
+static inline void arch_clear_pmem(void *addr, size_t size)
 {
 	BUG();
 }
 
-static inline void arch_wb_cache_pmem(void __pmem *addr, size_t size)
+static inline void arch_wb_cache_pmem(void *addr, size_t size)
 {
 	BUG();
 }
 
-static inline void arch_invalidate_pmem(void __pmem *addr, size_t size)
+static inline void arch_invalidate_pmem(void *addr, size_t size)
 {
 	BUG();
 }
@@ -77,13 +65,6 @@ static inline bool arch_has_pmem_api(void)
 	return IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API);
 }
 
-static inline int default_memcpy_from_pmem(void *dst, void __pmem const *src,
-		size_t size)
-{
-	memcpy(dst, (void __force *) src, size);
-	return 0;
-}
-
 /*
  * memcpy_from_pmem - read from persistent memory with error handling
  * @dst: destination buffer
@@ -92,54 +73,13 @@ static inline int default_memcpy_from_pmem(void *dst, void __pmem const *src,
  *
  * Returns 0 on success negative error code on failure.
  */
-static inline int memcpy_from_pmem(void *dst, void __pmem const *src,
-		size_t size)
+static inline int memcpy_from_pmem(void *dst, void const *src, size_t size)
 {
 	if (arch_has_pmem_api())
 		return arch_memcpy_from_pmem(dst, src, size);
 	else
-		return default_memcpy_from_pmem(dst, src, size);
-}
-
-/**
- * arch_has_wmb_pmem - true if wmb_pmem() ensures durability
- *
- * For a given cpu implementation within an architecture it is possible
- * that wmb_pmem() resolves to a nop.  In the case this returns
- * false, pmem api users are unable to ensure durability and may want to
- * fall back to a different data consistency model, or otherwise notify
- * the user.
- */
-static inline bool arch_has_wmb_pmem(void)
-{
-	return arch_has_pmem_api() && __arch_has_wmb_pmem();
-}
-
-/*
- * These defaults seek to offer decent performance and minimize the
- * window between i/o completion and writes being durable on media.
- * However, it is undefined / architecture specific whether
- * ARCH_MEMREMAP_PMEM + default_memcpy_to_pmem is sufficient for
- * making data durable relative to i/o completion.
- */
-static inline void default_memcpy_to_pmem(void __pmem *dst, const void *src,
-		size_t size)
-{
-	memcpy((void __force *) dst, src, size);
-}
-
-static inline size_t default_copy_from_iter_pmem(void __pmem *addr,
-		size_t bytes, struct iov_iter *i)
-{
-	return copy_from_iter_nocache((void __force *)addr, bytes, i);
-}
-
-static inline void default_clear_pmem(void __pmem *addr, size_t size)
-{
-	if (size == PAGE_SIZE && ((unsigned long)addr & ~PAGE_MASK) == 0)
-		clear_page((void __force *)addr);
-	else
-		memset((void __force *)addr, 0, size);
+		memcpy(dst, src, size);
+	return 0;
 }
 
 /**
@@ -152,29 +92,14 @@ static inline void default_clear_pmem(void __pmem *addr, size_t size)
  * being effectively evicted from, or never written to, the processor
  * cache hierarchy after the copy completes.  After memcpy_to_pmem()
  * data may still reside in cpu or platform buffers, so this operation
- * must be followed by a wmb_pmem().
+ * must be followed by a blkdev_issue_flush() on the pmem block device.
  */
-static inline void memcpy_to_pmem(void __pmem *dst, const void *src, size_t n)
+static inline void memcpy_to_pmem(void *dst, const void *src, size_t n)
 {
 	if (arch_has_pmem_api())
 		arch_memcpy_to_pmem(dst, src, n);
 	else
-		default_memcpy_to_pmem(dst, src, n);
-}
-
-/**
- * wmb_pmem - synchronize writes to persistent memory
- *
- * After a series of memcpy_to_pmem() operations this drains data from
- * cpu write buffers and any platform (memory controller) buffers to
- * ensure that written data is durable on persistent memory media.
- */
-static inline void wmb_pmem(void)
-{
-	if (arch_has_wmb_pmem())
-		arch_wmb_pmem();
-	else
-		wmb();
+		memcpy(dst, src, n);
 }
 
 /**
@@ -184,14 +109,14 @@ static inline void wmb_pmem(void)
  * @i:		iterator with source data
  *
  * Copy data from the iterator 'i' to the PMEM buffer starting at 'addr'.
- * This function requires explicit ordering with a wmb_pmem() call.
+ * See blkdev_issue_flush() note for memcpy_to_pmem().
  */
-static inline size_t copy_from_iter_pmem(void __pmem *addr, size_t bytes,
+static inline size_t copy_from_iter_pmem(void *addr, size_t bytes,
 		struct iov_iter *i)
 {
 	if (arch_has_pmem_api())
 		return arch_copy_from_iter_pmem(addr, bytes, i);
-	return default_copy_from_iter_pmem(addr, bytes, i);
+	return copy_from_iter_nocache(addr, bytes, i);
 }
 
 /**
@@ -200,14 +125,14 @@ static inline size_t copy_from_iter_pmem(void __pmem *addr, size_t bytes,
  * @size:	number of bytes to zero
  *
  * Write zeros into the memory range starting at 'addr' for 'size' bytes.
- * This function requires explicit ordering with a wmb_pmem() call.
+ * See blkdev_issue_flush() note for memcpy_to_pmem().
  */
-static inline void clear_pmem(void __pmem *addr, size_t size)
+static inline void clear_pmem(void *addr, size_t size)
 {
 	if (arch_has_pmem_api())
 		arch_clear_pmem(addr, size);
 	else
-		default_clear_pmem(addr, size);
+		memset(addr, 0, size);
 }
 
 /**
@@ -218,7 +143,7 @@ static inline void clear_pmem(void __pmem *addr, size_t size)
  * For platforms that support clearing poison this flushes any poisoned
  * ranges out of the cache
  */
-static inline void invalidate_pmem(void __pmem *addr, size_t size)
+static inline void invalidate_pmem(void *addr, size_t size)
 {
 	if (arch_has_pmem_api())
 		arch_invalidate_pmem(addr, size);
@@ -230,9 +155,9 @@ static inline void invalidate_pmem(void __pmem *addr, size_t size)
  * @size:	number of bytes to write back
  *
  * Write back the processor cache range starting at 'addr' for 'size' bytes.
- * This function requires explicit ordering with a wmb_pmem() call.
+ * See blkdev_issue_flush() note for memcpy_to_pmem().
  */
-static inline void wb_cache_pmem(void __pmem *addr, size_t size)
+static inline void wb_cache_pmem(void *addr, size_t size)
 {
 	if (arch_has_pmem_api())
 		arch_wb_cache_pmem(addr, size);