diff --git a/include/linux/dax.h b/include/linux/dax.h index 8b535bc4526f..9bd8528bd305 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -56,6 +56,18 @@ static inline void set_dax_synchronous(struct dax_device *dax_dev) { __set_dax_synchronous(dax_dev); } +/* + * Check if given mapping is supported by the file / underlying device. + */ +static inline bool daxdev_mapping_supported(struct vm_area_struct *vma, + struct dax_device *dax_dev) +{ + if (!(vma->vm_flags & VM_SYNC)) + return true; + if (!IS_DAX(file_inode(vma->vm_file))) + return false; + return dax_synchronous(dax_dev); +} #else static inline struct dax_device *dax_get_by_host(const char *host) { @@ -90,6 +102,11 @@ static inline bool dax_synchronous(struct dax_device *dax_dev) static inline void set_dax_synchronous(struct dax_device *dax_dev) { } +static inline bool daxdev_mapping_supported(struct vm_area_struct *vma, + struct dax_device *dax_dev) +{ + return !(vma->vm_flags & VM_SYNC); +} #endif struct writeback_control;