freebsd-nq/config/kernel-tmpfile.m4
Chunwei Chen ace1eae84c Add support for O_TMPFILE
Linux 3.11 add O_TMPFILE to open(2), which allow creating an unlinked file on
supported filesystem. It's basically doing open(2) and unlink(2) atomically.

The filesystem support is added through i_op->tmpfile. We basically copy the
create operation except we get rid of the link and name related stuff and add
the new node to unlinked set.

We also add support for linkat(2) to link tmpfile. However, since all previous
file operation will skip ZIL, we force a txg_wait_synced to make sure we are
sync safe.

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
2016-11-04 10:46:40 -07:00

24 lines
523 B
Plaintext

dnl #
dnl # 3.11 API change
dnl # Add support for i_op->tmpfile
dnl #
AC_DEFUN([ZFS_AC_KERNEL_TMPFILE], [
AC_MSG_CHECKING([whether i_op->tmpfile() exists])
ZFS_LINUX_TRY_COMPILE([
#include <linux/fs.h>
int tmpfile(struct inode *inode, struct dentry *dentry,
umode_t mode) { return 0; }
static struct inode_operations
iops __attribute__ ((unused)) = {
.tmpfile = tmpfile,
};
],[
],[
AC_MSG_RESULT(yes)
AC_DEFINE(HAVE_TMPFILE, 1,
[i_op->tmpfile() exists])
],[
AC_MSG_RESULT(no)
])
])