LU-6038 osd-zfs: Avoid redefining KM_SLEEP

Due to some long overdue memory management cleanup in the ZoL kmem
implementation the definition of KM_SLEEP has changed.  This change
was expected to be transparent to consumers but it causes issues
for Lustre because it explicitly redefines KM_SLEEP.  This was
originally done to avoid overriding the Linux slab interfaces.

This change implements a more portable fix.  Instead of preventing
the inclusion of the kmem.h header by setting the guard.  The
kmem_cache_* preprocessor macros are explictly undefined to make
the Linux interface available.

The related ZoL pull requests are as follows:

  https://github.com/zfsonlinux/spl/pull/414
  https://github.com/zfsonlinux/zfs/pull/2918

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Change-Id: Id1d19d7b4c440808b8b3fd042f687b10c1b869f3
Reviewed-on: http://review.whamcloud.com/13096
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Reviewed-by: Isaac Huang <he.huang@intel.com>
Reviewed-by: Nathaniel Clark <nathaniel.l.clark@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>

diff --git a/lustre/osd-zfs/osd_internal.h b/lustre/osd-zfs/osd_internal.h
index c6166f2..988ccb5 100644 (file)
--- a/lustre/osd-zfs/osd_internal.h
+++ b/lustre/osd-zfs/osd_internal.h
@@ -47,23 +47,35 @@
 #include <dt_object.h>
 #include <md_object.h>
 #include <lustre_quota.h>
-
-#define _SPL_KMEM_H
-/* SPL redefines this but to the same value: ~0UL vs -1, but GCC complains.
- * fixed in SPL master 52479ecf58fa89190e384edcf838fecccc786af5 */
+#ifdef SHRINK_STOP
 #undef SHRINK_STOP
-#include <sys/kstat.h>
-#define kmem_zalloc(a, b)      kzalloc(a, b)
-#define kmem_free(ptr, sz)     ((void)(sz), kfree(ptr))
-#ifndef KM_SLEEP
-#define KM_SLEEP               GFP_KERNEL
 #endif
-
 #include <sys/arc.h>
 #include <sys/nvpair.h>
 #include <sys/zfs_znode.h>
 #include <sys/zap.h>
 
+/**
+ * By design including kmem.h overrides the Linux slab interfaces to provide
+ * the Illumos kmem cache interfaces.  To override this and gain access to
+ * the Linux interfaces these preprocessor macros must be undefined.
+ */
+#ifdef kmem_cache_destroy
+#undef kmem_cache_destroy
+#endif
+
+#ifdef kmem_cache_create
+#undef kmem_cache_create
+#endif
+
+#ifdef kmem_cache_alloc
+#undef kmem_cache_alloc
+#endif
+
+#ifdef kmem_cache_free
+#undef kmem_cache_free
+#endif
+
 #define LUSTRE_ROOT_FID_SEQ    0
 #define DMU_OSD_SVNAME         "svname"
 #define DMU_OSD_OI_NAME_BASE   "oi"