dax, xfs, ext4: compile out iomap-dax paths in the FS_DAX=n case
authorDan Williams <dan.j.williams@intel.com>
Sat, 13 May 2017 23:31:05 +0000 (16:31 -0700)
committerDan Williams <dan.j.williams@intel.com>
Sun, 14 May 2017 00:52:16 +0000 (17:52 -0700)
commitf5705aa8cfed142d980ecac12bee0d81b756479e
tree4cd70192b0c38754b9113066222c0c9803695ddb
parent9d109081c261d87fc84e0cce245796796ae4c460
dax, xfs, ext4: compile out iomap-dax paths in the FS_DAX=n case

Tetsuo reports:

  fs/built-in.o: In function `xfs_file_iomap_end':
  xfs_iomap.c:(.text+0xe0ef9): undefined reference to `put_dax'
  fs/built-in.o: In function `xfs_file_iomap_begin':
  xfs_iomap.c:(.text+0xe1a7f): undefined reference to `dax_get_by_host'
  make: *** [vmlinux] Error 1
  $ grep DAX .config
  CONFIG_DAX=m
  # CONFIG_DEV_DAX is not set
  # CONFIG_FS_DAX is not set

When FS_DAX=n we can/must throw away the dax code in filesystems.
Implement 'fs_' versions of dax_get_by_host() and put_dax() that are
nops in the FS_DAX=n case.

Cc: <linux-xfs@vger.kernel.org>
Cc: <linux-ext4@vger.kernel.org>
Cc: Jan Kara <jack@suse.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Tested-by: Tony Luck <tony.luck@intel.com>
Fixes: ef51042472f5 ("block, dax: move 'select DAX' from BLOCK to FS_DAX")
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
fs/ext2/inode.c
fs/ext4/inode.c
fs/xfs/xfs_iomap.c
include/linux/dax.h