From d1a5f2b4d8a125943dcb6b032fc7eaefc2c78296 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Thu, 28 Jan 2016 20:25:31 -0800 Subject: block: use DAX for partition table reads Avoid populating pagecache when the block device is in DAX mode. Otherwise these page cache entries collide with the fsync/msync implementation and break data durability guarantees. Cc: Jan Kara Cc: Jeff Moyer Cc: Christoph Hellwig Cc: Dave Chinner Cc: Andrew Morton Reported-by: Ross Zwisler Tested-by: Ross Zwisler Reviewed-by: Matthew Wilcox Signed-off-by: Dan Williams --- include/linux/dax.h | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'include/linux/dax.h') diff --git a/include/linux/dax.h b/include/linux/dax.h index 8204c3dc3800..818e45078929 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -14,6 +14,17 @@ int dax_fault(struct vm_area_struct *, struct vm_fault *, get_block_t, dax_iodone_t); int __dax_fault(struct vm_area_struct *, struct vm_fault *, get_block_t, dax_iodone_t); + +#ifdef CONFIG_FS_DAX +struct page *read_dax_sector(struct block_device *bdev, sector_t n); +#else +static inline struct page *read_dax_sector(struct block_device *bdev, + sector_t n) +{ + return ERR_PTR(-ENXIO); +} +#endif + #ifdef CONFIG_TRANSPARENT_HUGEPAGE int dax_pmd_fault(struct vm_area_struct *, unsigned long addr, pmd_t *, unsigned int flags, get_block_t, dax_iodone_t); -- cgit v1.2.3-59-g8ed1b