mirror_zfs/config/kernel-truncate-setsize.m4

dnl #
dnl # 2.6.35 API change
dnl # Added truncate_setsize() helper function.
dnl #
AC_DEFUN([ZFS_AC_KERNEL_TRUNCATE_SETSIZE],
	[AC_MSG_CHECKING([whether truncate_setsize() is available])
	ZFS_LINUX_TRY_COMPILE_SYMBOL([
		#include <linux/mm.h>
	], [
		truncate_setsize(NULL, 0);
	], [truncate_setsize], [mm/truncate.c], [
		AC_MSG_RESULT(yes)
		AC_DEFINE(HAVE_TRUNCATE_SETSIZE, 1,
		          [truncate_setsize() is available])
	], [
		AC_MSG_RESULT(no)
	])
])
Tear down and flush the mmap region The inode eviction should unmap the pages associated with the inode. These pages should also be flushed to disk to avoid the data loss. Therefore, use truncate_setsize() in evict_inode() to release the pagecache. The API truncate_setsize() was added in 2.6.35 kernel. To ensure compatibility with the old kernel, the patch defines its own truncate_setsize function. Signed-off-by: Prasad Joshi <pjoshi@stec-inc.com> Closes #255 2011-06-25 16:30:29 +04:00			`dnl #`
			`dnl # 2.6.35 API change`
			`dnl # Added truncate_setsize() helper function.`
			`dnl #`
When checking for symbol exports, try compiling. This patch adds a new autoconf function: ZFS_LINUX_TRY_COMPILE_SYMBOL. This new function does the following: - Call LINUX_TRY_COMPILE with the specified parameters. - If unsuccessful, return false. - If successful and we're configuring with --enable-linux-builtin, return true. - Else, call CHECK_SYMBOL_EXPORT with the specified parameters and return the result. All calls to CHECK_SYMBOL_EXPORT are converted to LINUX_TRY_COMPILE_SYMBOL so that the tests work even when configuring for builtin on a kernel which doesn't have loadable module support, or hasn't been built yet. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #851 2012-07-26 01:38:58 +04:00			`AC_DEFUN([ZFS_AC_KERNEL_TRUNCATE_SETSIZE],`
			`[AC_MSG_CHECKING([whether truncate_setsize() is available])`
			`ZFS_LINUX_TRY_COMPILE_SYMBOL([`
			`#include <linux/mm.h>`
			`], [`
			`truncate_setsize(NULL, 0);`
			`], [truncate_setsize], [mm/truncate.c], [`
			`AC_MSG_RESULT(yes)`
			`AC_DEFINE(HAVE_TRUNCATE_SETSIZE, 1,`
			`[truncate_setsize() is available])`
			`], [`
			`AC_MSG_RESULT(no)`
			`])`
Tear down and flush the mmap region The inode eviction should unmap the pages associated with the inode. These pages should also be flushed to disk to avoid the data loss. Therefore, use truncate_setsize() in evict_inode() to release the pagecache. The API truncate_setsize() was added in 2.6.35 kernel. To ensure compatibility with the old kernel, the patch defines its own truncate_setsize function. Signed-off-by: Prasad Joshi <pjoshi@stec-inc.com> Closes #255 2011-06-25 16:30:29 +04:00			`])`