Revision 4759d386d55fef452d692bf101167914437e848e authored by Linus Torvalds on 01 January 2017, 20:27:05 UTC, committed by Linus Torvalds on 01 January 2017, 20:27:05 UTC
Pull DAX updates from Dan Williams:
 "The completion of Jan's DAX work for 4.10.

  As I mentioned in the libnvdimm-for-4.10 pull request, these are some
  final fixes for the DAX dirty-cacheline-tracking invalidation work
  that was merged through the -mm, ext4, and xfs trees in -rc1. These
  patches were prepared prior to the merge window, but we waited for
  4.10-rc1 to have a stable merge base after all the prerequisites were
  merged.

  Quoting Jan on the overall changes in these patches:

     "So I'd like all these 6 patches to go for rc2. The first three
      patches fix invalidation of exceptional DAX entries (a bug which
      is there for a long time) - without these patches data loss can
      occur on power failure even though user called fsync(2). The other
      three patches change locking of DAX faults so that ->iomap_begin()
      is called in a more relaxed locking context and we are safe to
      start a transaction there for ext4"

  These have received a build success notification from the kbuild
  robot, and pass the latest libnvdimm unit tests. There have not been
  any -next releases since -rc1, so they have not appeared there"

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  ext4: Simplify DAX fault path
  dax: Call ->iomap_begin without entry lock during dax fault
  dax: Finish fault completely when loading holes
  dax: Avoid page invalidation races and unnecessary radix tree traversals
  mm: Invalidate DAX radix tree entries only if appropriate
  ext2: Return BH_New buffers for zeroed blocks
2 parent s 238d1d0 + 1db1754
Raw File
shmbuf.h
#ifndef __ASM_GENERIC_SHMBUF_H
#define __ASM_GENERIC_SHMBUF_H

#include <asm/bitsperlong.h>

/*
 * The shmid64_ds structure for x86 architecture.
 * Note extra padding because this structure is passed back and forth
 * between kernel and user space.
 *
 * shmid64_ds was originally meant to be architecture specific, but
 * everyone just ended up making identical copies without specific
 * optimizations, so we may just as well all use the same one.
 *
 * 64 bit architectures typically define a 64 bit __kernel_time_t,
 * so they do not need the first two padding words.
 * On big-endian systems, the padding is in the wrong place.
 *
 *
 * Pad space is left for:
 * - 64-bit time_t to solve y2038 problem
 * - 2 miscellaneous 32-bit values
 */

struct shmid64_ds {
	struct ipc64_perm	shm_perm;	/* operation perms */
	size_t			shm_segsz;	/* size of segment (bytes) */
	__kernel_time_t		shm_atime;	/* last attach time */
#if __BITS_PER_LONG != 64
	unsigned long		__unused1;
#endif
	__kernel_time_t		shm_dtime;	/* last detach time */
#if __BITS_PER_LONG != 64
	unsigned long		__unused2;
#endif
	__kernel_time_t		shm_ctime;	/* last change time */
#if __BITS_PER_LONG != 64
	unsigned long		__unused3;
#endif
	__kernel_pid_t		shm_cpid;	/* pid of creator */
	__kernel_pid_t		shm_lpid;	/* pid of last operator */
	__kernel_ulong_t	shm_nattch;	/* no. of current attaches */
	__kernel_ulong_t	__unused4;
	__kernel_ulong_t	__unused5;
};

struct shminfo64 {
	__kernel_ulong_t	shmmax;
	__kernel_ulong_t	shmmin;
	__kernel_ulong_t	shmmni;
	__kernel_ulong_t	shmseg;
	__kernel_ulong_t	shmall;
	__kernel_ulong_t	__unused1;
	__kernel_ulong_t	__unused2;
	__kernel_ulong_t	__unused3;
	__kernel_ulong_t	__unused4;
};

#endif /* __ASM_GENERIC_SHMBUF_H */
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