LU-6215 gss: cache_head is now on a hlist in 4.3+ kernels

Since kernel 4.3 struct cache_head switched from a single
list to a hlist. This patch handles the change.

Linux-commit: 129e5824cd96d9289679973f0ff7c48e88d569bb

Signed-off-by: Li Dongyang <dongyang.li@anu.edu.au>
Change-Id: Iec4c7d0acf106a8f7b60d72eb2038b6d9e12f422
Reviewed-on: http://review.whamcloud.com/18728
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>

diff --git a/lustre/autoconf/lustre-core.m4 b/lustre/autoconf/lustre-core.m4
index ddab73d..00b376f 100644 (file)
--- a/lustre/autoconf/lustre-core.m4
+++ b/lustre/autoconf/lustre-core.m4
@@ -1974,6 +1974,23 @@ LB_CHECK_FILE([$LINUX/include/linux/loop.h], [
 ]) # LC_HAVE_LOOP_CTL_GET_FREE
 
 #
+# LC_HAVE_CACHE_HEAD_HLIST
+#
+# 4.3 kernel swiched to hlist for cache_head
+#
+AC_DEFUN([LC_HAVE_CACHE_HEAD_HLIST], [
+LB_CHECK_COMPILE([if 'struct cache_head' has 'cache_list' field],
+cache_head_has_hlist, [
+       #include <linux/sunrpc/cache.h>
+],[
+       do {} while(sizeof(((struct cache_head *)0)->cache_list));
+],[
+       AC_DEFINE(HAVE_CACHE_HEAD_HLIST, 1,
+               [cache_head has hlist cache_list])
+])
+]) # LC_HAVE_CACHE_HEAD_HLIST
+
+#
 # LC_PROG_LINUX
 #
 # Lustre linux kernel checks
@@ -2135,6 +2152,9 @@ AC_DEFUN([LC_PROG_LINUX], [
        LC_BIO_ENDIO_USES_ONE_ARG
        LC_SYMLINK_OPS_USE_NAMEIDATA
 
+       # 4.3
+       LC_HAVE_CACHE_HEAD_HLIST
+
        #
        AS_IF([test "x$enable_server" != xno], [
                LC_FUNC_DEV_SET_RDONLY

diff --git a/lustre/ptlrpc/gss/gss_svc_upcall.c b/lustre/ptlrpc/gss/gss_svc_upcall.c
index 429b1eb..2786d69 100644 (file)
--- a/lustre/ptlrpc/gss/gss_svc_upcall.c
+++ b/lustre/ptlrpc/gss/gss_svc_upcall.c
@@ -149,7 +149,11 @@ struct rsi {
        int                     major_status, minor_status;
 };
 
+#ifdef HAVE_CACHE_HEAD_HLIST
+static struct hlist_head rsi_table[RSI_HASHMAX];
+#else
 static struct cache_head *rsi_table[RSI_HASHMAX];
+#endif
 static struct cache_detail rsi_cache;
 static struct rsi *rsi_update(struct rsi *new, struct rsi *old);
 static struct rsi *rsi_lookup(struct rsi *item);
@@ -242,7 +246,11 @@ static void rsi_put(struct kref *ref)
 {
         struct rsi *rsi = container_of(ref, struct rsi, h.ref);
 
-        LASSERT(rsi->h.next == NULL);
+#ifdef HAVE_CACHE_HEAD_HLIST
+       LASSERT(rsi->h.cache_list.next == NULL);
+#else
+       LASSERT(rsi->h.next == NULL);
+#endif
         rsi_free(rsi);
         OBD_FREE_PTR(rsi);
 }
@@ -430,7 +438,11 @@ struct rsc {
         struct gss_svc_ctx      ctx;
 };
 
+#ifdef HAVE_CACHE_HEAD_HLIST
+static struct hlist_head rsc_table[RSC_HASHMAX];
+#else
 static struct cache_head *rsc_table[RSC_HASHMAX];
+#endif
 static struct cache_detail rsc_cache;
 static struct rsc *rsc_update(struct rsc *new, struct rsc *old);
 static struct rsc *rsc_lookup(struct rsc *item);
@@ -477,7 +489,11 @@ static void rsc_put(struct kref *ref)
 {
         struct rsc *rsci = container_of(ref, struct rsc, h.ref);
 
+#ifdef HAVE_CACHE_HEAD_HLIST
+       LASSERT(rsci->h.cache_list.next == NULL);
+#else
         LASSERT(rsci->h.next == NULL);
+#endif
         rsc_free(rsci);
         OBD_FREE_PTR(rsci);
 }
@@ -693,24 +709,41 @@ typedef int rsc_entry_match(struct rsc *rscp, long data);
 
 static void rsc_flush(rsc_entry_match *match, long data)
 {
-        struct cache_head **ch;
+#ifdef HAVE_CACHE_HEAD_HLIST
+       struct cache_head *ch = NULL;
+       struct hlist_head *head;
+#else
+       struct cache_head **ch;
+#endif
         struct rsc *rscp;
         int n;
         ENTRY;
 
        write_lock(&rsc_cache.hash_lock);
         for (n = 0; n < RSC_HASHMAX; n++) {
-                for (ch = &rsc_cache.hash_table[n]; *ch;) {
-                        rscp = container_of(*ch, struct rsc, h);
+#ifdef HAVE_CACHE_HEAD_HLIST
+               head = &rsc_cache.hash_table[n];
+               hlist_for_each_entry(ch, head, cache_list) {
+                       rscp = container_of(ch, struct rsc, h);
+#else
+               for (ch = &rsc_cache.hash_table[n]; *ch;) {
+                       rscp = container_of(*ch, struct rsc, h);
+#endif
 
                         if (!match(rscp, data)) {
-                                ch = &((*ch)->next);
+#ifndef HAVE_CACHE_HEAD_HLIST
+                               ch = &((*ch)->next);
+#endif
                                 continue;
                         }
 
                         /* it seems simply set NEGATIVE doesn't work */
-                        *ch = (*ch)->next;
-                        rscp->h.next = NULL;
+#ifdef HAVE_CACHE_HEAD_HLIST
+                       hlist_del_init(&ch->cache_list);
+#else
+                       *ch = (*ch)->next;
+                       rscp->h.next = NULL;
+#endif
                         cache_get(&rscp->h);
                        set_bit(CACHE_NEGATIVE, &rscp->h.flags);
                         COMPAT_RSC_PUT(&rscp->h, &rsc_cache);