Pull pstore updates from Kees Cook:
 "This has a large internal refactoring along with several smaller
  fixes.

   - constify compression structures; Bhumika Goyal

   - restore powerpc dumping; Ankit Kumar

   - fix more bugs in the rarely exercises module unloading logic

   - reorganize filesystem locking to fix problems noticed by lockdep

   - refactor internal pstore APIs to make development and review
     easier:
      - improve error reporting
      - add kernel-doc structure and function comments
      - avoid insane argument passing by using a common record
        structure"

* tag 'pstore-v4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (23 commits)
  pstore: Solve lockdep warning by moving inode locks
  pstore: Fix flags to enable dumps on powerpc
  pstore: Remove unused vmalloc.h in pmsg
  pstore: simplify write_user_compat()
  pstore: Remove write_buf() callback
  pstore: Replace arguments for write_buf_user() API
  pstore: Replace arguments for write_buf() API
  pstore: Replace arguments for erase() API
  pstore: Do not duplicate record metadata
  pstore: Allocate records on heap instead of stack
  pstore: Pass record contents instead of copying
  pstore: Always allocate buffer for decompression
  pstore: Replace arguments for write() API
  pstore: Replace arguments for read() API
  pstore: Switch pstore_mkfile to pass record
  pstore: Move record decompression to function
  pstore: Extract common arguments into structure
  pstore: Add kernel-doc for struct pstore_info
  pstore: Improve register_pstore() error reporting
  pstore: Avoid race in module unloading
  ...