diff options
| -rw-r--r-- | fs/dax.c | 17 | ||||
| -rw-r--r-- | include/linux/dax.h | 3 |
2 files changed, 14 insertions, 6 deletions
@@ -32,14 +32,19 @@ #include <linux/pfn_t.h> #include <linux/sizes.h> -#define RADIX_DAX_MASK 0xf -#define RADIX_DAX_SHIFT 4 -#define RADIX_DAX_PTE (0x4 | RADIX_TREE_EXCEPTIONAL_ENTRY) -#define RADIX_DAX_PMD (0x8 | RADIX_TREE_EXCEPTIONAL_ENTRY) -#define RADIX_DAX_TYPE(entry) ((unsigned long)entry & RADIX_DAX_MASK) +/* + * We use lowest available bit in exceptional entry for locking, other two + * bits to determine entry type. In total 3 special bits. + */ +#define RADIX_DAX_SHIFT (RADIX_TREE_EXCEPTIONAL_SHIFT + 3) +#define RADIX_DAX_PTE (1 << (RADIX_TREE_EXCEPTIONAL_SHIFT + 1)) +#define RADIX_DAX_PMD (1 << (RADIX_TREE_EXCEPTIONAL_SHIFT + 2)) +#define RADIX_DAX_TYPE_MASK (RADIX_DAX_PTE | RADIX_DAX_PMD) +#define RADIX_DAX_TYPE(entry) ((unsigned long)entry & RADIX_DAX_TYPE_MASK) #define RADIX_DAX_SECTOR(entry) (((unsigned long)entry >> RADIX_DAX_SHIFT)) #define RADIX_DAX_ENTRY(sector, pmd) ((void *)((unsigned long)sector << \ - RADIX_DAX_SHIFT | (pmd ? RADIX_DAX_PMD : RADIX_DAX_PTE))) + RADIX_DAX_SHIFT | (pmd ? RADIX_DAX_PMD : RADIX_DAX_PTE) | \ + RADIX_TREE_EXCEPTIONAL_ENTRY)) static long dax_map_atomic(struct block_device *bdev, struct blk_dax_ctl *dax) { diff --git a/include/linux/dax.h b/include/linux/dax.h index 72dc81de3ddb..70600b63083f 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -5,6 +5,9 @@ #include <linux/mm.h> #include <asm/pgtable.h> +/* We use lowest available exceptional entry bit for locking */ +#define RADIX_DAX_ENTRY_LOCK (1 << RADIX_TREE_EXCEPTIONAL_SHIFT) + ssize_t dax_do_io(struct kiocb *, struct inode *, struct iov_iter *, loff_t, get_block_t, dio_iodone_t, int flags); int dax_zero_page_range(struct inode *, loff_t from, unsigned len, get_block_t); |