Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit c046c321 authored by Dan Williams's avatar Dan Williams Committed by Linus Torvalds
Browse files

dax: re-enable dax pmd mappings 



Now that the get_user_pages() path knows how to handle dax-pmd mappings,
remove the protections that disabled dax-pmd support.

Tests available from github.com/pmem/ndctl:

    make TESTS="lib/test-dax.sh lib/test-mmap.sh" check

Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent cbb38e41

fs/Kconfig

+2 −1
Original line number Diff line number Diff line
@@ -50,7 +50,8 @@ config FS_DAX_PMD 
	bool

	default FS_DAX

	depends on FS_DAX

	depends on BROKEN

	depends on ZONE_DEVICE

	depends on TRANSPARENT_HUGEPAGE



endif # BLOCK

fs/dax.c

+2 −6
Original line number Diff line number Diff line
@@ -592,7 +592,7 @@ int __dax_pmd_fault(struct vm_area_struct *vma, unsigned long address, 
	sector_t block;

	int result = 0;



	/* dax pmd mappings are broken wrt gup and fork */

	/* dax pmd mappings require pfn_t_devmap() */

	if (!IS_ENABLED(CONFIG_FS_DAX_PMD))

		return VM_FAULT_FALLBACK;
@@ -717,11 +717,7 @@ int __dax_pmd_fault(struct vm_area_struct *vma, unsigned long address, 
			goto fallback;

		}



		/*

		 * TODO: teach vmf_insert_pfn_pmd() to support

		 * 'pte_special' for pmds

		 */

		if (pfn_t_has_page(dax.pfn)) {

		if (!pfn_t_devmap(dax.pfn)) {

			dax_unmap_atomic(bdev, &dax);

			dax_pmd_dbg(&bh, address, "pfn not in memmap");

			goto fallback;