From 785a3fab4adbf91b2189c928a59ae219c54ba95e Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Mon, 23 Oct 2017 07:20:00 -0700 Subject: mm, dax: introduce pfn_t_special() In support of removing the VM_MIXEDMAP indication from DAX VMAs, introduce pfn_t_special() for drivers to indicate that _PAGE_SPECIAL should be used for DAX ptes. This also helps identify drivers like dccssblk that only want to use DAX in a read-only fashion without get_user_pages() support. Ideally we could delete axonram and dcssblk DAX support, but if we need to keep it better make it explicit that axonram and dcssblk only support a sub-set of DAX due to missing _PAGE_DEVMAP support. Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: Martin Schwidefsky Cc: Heiko Carstens Signed-off-by: Dan Williams --- drivers/s390/block/dcssblk.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/s390/block/dcssblk.c') diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c index 6aaefb780436..9cae08b36b80 100644 --- a/drivers/s390/block/dcssblk.c +++ b/drivers/s390/block/dcssblk.c @@ -916,7 +916,8 @@ __dcssblk_direct_access(struct dcssblk_dev_info *dev_info, pgoff_t pgoff, dev_sz = dev_info->end - dev_info->start + 1; *kaddr = (void *) dev_info->start + offset; - *pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset), PFN_DEV); + *pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset), + PFN_DEV|PFN_SPECIAL); return (dev_sz - offset) / PAGE_SIZE; } -- cgit