Merge branch 'kmem-rework'

The core motivation behind these changes is to minimize the
memory management differences between ZFS on Linux and other
platforms.  This simplifies the process of porting changes to
Linux from other platforms.  This is good for code quality
and is expected to reduce the number of defects accidentally
introduced due to porting.

The key reason this is now possible is due to the addition of
Linux features such as the thread-specific PF_FSTRANS bit which
was introduced for XFS.

This patch stack also performs some refactoring and cleanup
designed to make the code more maintainable and understandable.
Finally, in the context of making and testing these changes
several bugs were identified and resolved resulting in a
more robust implementation.

Signed-off-by: Brian Behlendorf <[email protected]>
Signed-off-by: Richard Yao <[email protected]>
Signed-off-by: Tim Chase <[email protected]>
Closes openzfs#414

include/linux/proc_compat.h

@@ -22,8 +22,8 @@
  *  with the SPL.  If not, see <http://www.gnu.org/licenses/>.
 \*****************************************************************************/
 
-#ifndef _SPL_PROC_H
-#define _SPL_PROC_H
+#ifndef _SPL_PROC_COMPAT_H
+#define _SPL_PROC_COMPAT_H
 
 #include <linux/proc_fs.h>
 
@@ -32,4 +32,4 @@ extern struct proc_dir_entry *proc_spl_kstat;
 int spl_proc_init(void);
 void spl_proc_fini(void);
 
-#endif /* SPL_PROC_H */
+#endif /* SPL_PROC_COMPAT_H */

include/sys/Makefile.am

@@ -44,6 +44,7 @@ KERNEL_H = \
 	$(top_srcdir)/include/sys/isa_defs.h \
 	$(top_srcdir)/include/sys/kidmap.h \
 	$(top_srcdir)/include/sys/kmem.h \
+	$(top_srcdir)/include/sys/kmem_cache.h \
 	$(top_srcdir)/include/sys/kobj.h \
 	$(top_srcdir)/include/sys/kstat.h \
 	$(top_srcdir)/include/sys/list.h \
@@ -94,6 +95,7 @@ KERNEL_H = \
 	$(top_srcdir)/include/sys/varargs.h \
 	$(top_srcdir)/include/sys/vfs.h \
 	$(top_srcdir)/include/sys/vfs_opreg.h \
+	$(top_srcdir)/include/sys/vmem.h \
 	$(top_srcdir)/include/sys/vmsystm.h \
 	$(top_srcdir)/include/sys/vnode.h \
 	$(top_srcdir)/include/sys/zmod.h \