From c046c321cb4a0bdac9fb922db3859893ca556d27 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Fri, 15 Jan 2016 16:57:01 -0800 Subject: [PATCH] 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: Dan Williams Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/Kconfig | 3 ++- fs/dax.c | 8 ++------ 2 files changed, 4 insertions(+), 7 deletions(-) diff --git a/fs/Kconfig b/fs/Kconfig index 2bb1ef86c411..9adee0d7536e 100644 --- a/fs/Kconfig +++ b/fs/Kconfig @@ -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 diff --git a/fs/dax.c b/fs/dax.c index e1f251dc9654..7af879759064 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -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; -- 2.20.1