kernel/linux.git/include/linux/dax.h, branch linux-5.8.y

dax: Fix compilation for CONFIG_DAX && !CONFIG_FS_DAX

2020-09-23T11:00:03+00:00

commit 88b67edd7247466bc47f01e1dc539b0d0d4b931e upstream. dax_supported() is defined whenever CONFIG_DAX is enabled. So dummy implementation should be defined only in !CONFIG_DAX case, not in !CONFIG_FS_DAX case. Fixes: e2ec51282545 ("dm: Call proper helper to determine dax support") Cc: Reported-by: Geert Uytterhoeven Reported-by: Naresh Kamboju Reported-by: kernel test robot Signed-off-by: Jan Kara Signed-off-by: Dan Williams Signed-off-by: Greg Kroah-Hartman

dm: Call proper helper to determine dax support

2020-09-23T11:00:03+00:00

commit e2ec5128254518cae320d5dc631b71b94160f663 upstream. DM was calling generic_fsdax_supported() to determine whether a device referenced in the DM table supports DAX. However this is a helper for "leaf" device drivers so that they don't have to duplicate common generic checks. High level code should call dax_supported() helper which that calls into appropriate helper for the particular device. This problem manifested itself as kernel messages: dm-3: error: dax access failed (-95) when lvm2-testsuite run in cases where a DM device was stacked on top of another DM device. Fixes: 7bf7eac8d648 ("dax: Arrange for dax_supported check to span multiple devices") Cc: Tested-by: Adrian Huang Signed-off-by: Jan Kara Acked-by: Mike Snitzer Reported-by: kernel test robot Link: https://lore.kernel.org/r/160061715195.13131.5503173247632041975.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams Signed-off-by: Greg Kroah-Hartman

mm: don't include asm/pgtable.h if linux/mm.h is already included

2020-06-09T16:39:13+00:00

Patch series "mm: consolidate definitions of page table accessors", v2. The low level page table accessors (pXY_index(), pXY_offset()) are duplicated across all architectures and sometimes more than once. For instance, we have 31 definition of pgd_offset() for 25 supported architectures. Most of these definitions are actually identical and typically it boils down to, e.g. static inline unsigned long pmd_index(unsigned long address) { return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1); } static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address) { return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address); } These definitions can be shared among 90% of the arches provided XYZ_SHIFT, PTRS_PER_XYZ and xyz_page_vaddr() are defined. For architectures that really need a custom version there is always possibility to override the generic version with the usual ifdefs magic. These patches introduce include/linux/pgtable.h that replaces include/asm-generic/pgtable.h and add the definitions of the page table accessors to the new header. This patch (of 12): The linux/mm.h header includes to allow inlining of the functions involving page table manipulations, e.g. pte_alloc() and pmd_alloc(). So, there is no point to explicitly include in the files that include . The include statements in such cases are remove with a simple loop: for f in $(git grep -l "include ") ; do sed -i -e '/include / d' $f done Signed-off-by: Mike Rapoport Signed-off-by: Andrew Morton Cc: Arnd Bergmann Cc: Borislav Petkov Cc: Brian Cain Cc: Catalin Marinas Cc: Chris Zankel Cc: "David S. Miller" Cc: Geert Uytterhoeven Cc: Greentime Hu Cc: Greg Ungerer Cc: Guan Xuetao Cc: Guo Ren Cc: Heiko Carstens Cc: Helge Deller Cc: Ingo Molnar Cc: Ley Foon Tan Cc: Mark Salter Cc: Matthew Wilcox Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Simek Cc: Mike Rapoport Cc: Nick Hu Cc: Paul Walmsley Cc: Richard Weinberger Cc: Rich Felker Cc: Russell King Cc: Stafford Horne Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Tony Luck Cc: Vincent Chen Cc: Vineet Gupta Cc: Will Deacon Cc: Yoshinori Sato Link: http://lkml.kernel.org/r/20200514170327.31389-1-rppt@kernel.org Link: http://lkml.kernel.org/r/20200514170327.31389-2-rppt@kernel.org Signed-off-by: Linus Torvalds

dax,iomap: Add helper dax_iomap_zero() to zero a range

2020-04-03T02:15:03+00:00

Add a helper dax_ioamp_zero() to zero a range. This patch basically merges __dax_zero_page_range() and iomap_dax_zero(). Suggested-by: Christoph Hellwig Signed-off-by: Vivek Goyal Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20200228163456.1587-7-vgoyal@redhat.com Signed-off-by: Dan Williams

dax, pmem: Add a dax operation zero_page_range

2020-04-03T02:15:03+00:00

Add a dax operation zero_page_range, to zero a page. This will also clear any known poison in the page being zeroed. As of now, zeroing of one page is allowed in a single call. There are no callers which are trying to zero more than a page in a single call. Once we grow the callers which zero more than a page in single call, we can add that support. Primary reason for not doing that yet is that this will add little complexity in dm implementation where a range might be spanning multiple underlying targets and one will have to split the range into multiple sub ranges and call zero_page_range() on individual targets. Suggested-by: Christoph Hellwig Signed-off-by: Vivek Goyal Reviewed-by: Pankaj Gupta Link: https://lore.kernel.org/r/20200228163456.1587-3-vgoyal@redhat.com Signed-off-by: Dan Williams

dax: Get rid of fs_dax_get_by_host() helper

2020-01-16T17:52:27+00:00

Looks like nobody is using fs_dax_get_by_host() except fs_dax_get_by_bdev() and it can easily use dax_get_by_host() instead. IIUC, fs_dax_get_by_host() was only introduced so that one could compile with CONFIG_FS_DAX=n and CONFIG_DAX=m. fs_dax_get_by_bdev() achieves the same purpose and hence it looks like fs_dax_get_by_host() is not needed anymore. Signed-off-by: Vivek Goyal Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20200106181117.GA16248@redhat.com Signed-off-by: Dan Williams

dax: Pass dax_dev instead of bdev to dax_writeback_mapping_range()

2020-01-03T19:13:12+00:00

As of now dax_writeback_mapping_range() takes "struct block_device" as a parameter and dax_dev is searched from bdev name. This also involves taking a fresh reference on dax_dev and putting that reference at the end of function. We are developing a new filesystem virtio-fs and using dax to access host page cache directly. But there is no block device. IOW, we want to make use of dax but want to get rid of this assumption that there is always a block device associated with dax_dev. So pass in "struct dax_device" as parameter instead of bdev. ext2/ext4/xfs are current users and they already have a reference on dax_device. So there is no need to take reference and drop reference to dax_device on each call of this function. Suggested-by: Christoph Hellwig Reviewed-by: Christoph Hellwig Reviewed-by: Jan Kara Signed-off-by: Vivek Goyal Link: https://lore.kernel.org/r/20200103183307.GB13350@redhat.com Signed-off-by: Dan Williams

dax: check synchronous mapping is supported

2019-07-05T22:19:10+00:00

This patch introduces 'daxdev_mapping_supported' helper which checks if 'MAP_SYNC' is supported with filesystem mapping. It also checks if corresponding dax_device is synchronous. Virtio pmem device is asynchronous and does not not support VM_SYNC. Suggested-by: Jan Kara Signed-off-by: Pankaj Gupta Reviewed-by: Jan Kara Signed-off-by: Dan Williams

libnvdimm: add dax_dev sync flag

2019-07-05T22:19:10+00:00

This patch adds 'DAXDEV_SYNC' flag which is set for nd_region doing synchronous flush. This later is used to disable MAP_SYNC functionality for ext4 & xfs filesystem for devices don't support synchronous flush. Signed-off-by: Pankaj Gupta Signed-off-by: Dan Williams

dax: Arrange for dax_supported check to span multiple devices

2019-05-20T22:02:08+00:00

Pankaj reports that starting with commit ad428cdb525a "dax: Check the end of the block-device capacity with dax_direct_access()" device-mapper no longer allows dax operation. This results from the stricter checks in __bdev_dax_supported() that validate that the start and end of a block-device map to the same 'pagemap' instance. Teach the dax-core and device-mapper to validate the 'pagemap' on a per-target basis. This is accomplished by refactoring the bdev_dax_supported() internals into generic_fsdax_supported() which takes a sector range to validate. Consequently generic_fsdax_supported() is suitable to be used in a device-mapper ->iterate_devices() callback. A new ->dax_supported() operation is added to allow composite devices to split and route upper-level bdev_dax_supported() requests. Fixes: ad428cdb525a ("dax: Check the end of the block-device...") Cc: Cc: Ira Weiny Cc: Dave Jiang Cc: Keith Busch Cc: Matthew Wilcox Cc: Vishal Verma Cc: Heiko Carstens Cc: Martin Schwidefsky Reviewed-by: Jan Kara Reported-by: Pankaj Gupta Reviewed-by: Pankaj Gupta Tested-by: Pankaj Gupta Tested-by: Vaibhav Jain Reviewed-by: Mike Snitzer Signed-off-by: Dan Williams