Imported linux-2.6.27.39 suse/xen patches.

[ipfire-2.x.git] / src / patches / suse-2.6.27.39 / patches.fixes / nfsd-07-nfsd-idmap-drop-special-request-deferal-in-favour-of.patch

diff --git a/src/patches/suse-2.6.27.39/patches.fixes/nfsd-07-nfsd-idmap-drop-special-request-deferal-in-favour-of.patch b/src/patches/suse-2.6.27.39/patches.fixes/nfsd-07-nfsd-idmap-drop-special-request-deferal-in-favour-of.patch
new file mode 100644 (file)
index 0000000..2668559
--- /dev/null
+++ b/src/patches/suse-2.6.27.39/patches.fixes/nfsd-07-nfsd-idmap-drop-special-request-deferal-in-favour-of.patch
@@ -0,0 +1,141 @@
+Patch-mainline: submitted 04aug2009
+References: bnc#498708
+From: NeilBrown <neilb@suse.de>
+Date: Tue, 4 Aug 2009 15:06:39 +1000
+Subject: [PATCH 09/12] nfsd/idmap: drop special request deferal in favour of improved default.
+
+The idmap code manages request deferal by waiting for a reply from
+userspace rather than putting the NFS request on a queue to be retried
+from the start.
+Now that the comment deferal code does this there is no need for the
+special code in idmap.
+
+Signed-off-by: NeilBrown <neilb@suse.de>
+
+---
+ fs/nfsd/nfs4idmap.c |  105 +++++-----------------------------------------------
+ 1 file changed, 11 insertions(+), 94 deletions(-)
+
+--- linux-2.6.27-SLE11_BRANCH.orig/fs/nfsd/nfs4idmap.c
++++ linux-2.6.27-SLE11_BRANCH/fs/nfsd/nfs4idmap.c
+@@ -485,109 +485,26 @@ nfsd_idmap_shutdown(void)
+       cache_unregister(&nametoid_cache);
+ }
+ 
+-/*
+- * Deferred request handling
+- */
+-
+-struct idmap_defer_req {
+-       struct cache_req               req;
+-       struct cache_deferred_req deferred_req;
+-       wait_queue_head_t      waitq;
+-       atomic_t                       count;
+-};
+-
+-static inline void
+-put_mdr(struct idmap_defer_req *mdr)
+-{
+-      if (atomic_dec_and_test(&mdr->count))
+-              kfree(mdr);
+-}
+-
+-static inline void
+-get_mdr(struct idmap_defer_req *mdr)
+-{
+-      atomic_inc(&mdr->count);
+-}
+-
+-static void
+-idmap_revisit(struct cache_deferred_req *dreq, int toomany)
+-{
+-      struct idmap_defer_req *mdr =
+-              container_of(dreq, struct idmap_defer_req, deferred_req);
+-
+-      wake_up(&mdr->waitq);
+-      put_mdr(mdr);
+-}
+-
+-static struct cache_deferred_req *
+-idmap_defer(struct cache_req *req)
+-{
+-      struct idmap_defer_req *mdr =
+-              container_of(req, struct idmap_defer_req, req);
+-
+-      mdr->deferred_req.revisit = idmap_revisit;
+-      get_mdr(mdr);
+-      return (&mdr->deferred_req);
+-}
+-
+-static inline int
+-do_idmap_lookup(struct ent *(*lookup_fn)(struct ent *), struct ent *key,
+-              struct cache_detail *detail, struct ent **item,
+-              struct idmap_defer_req *mdr)
+-{
+-      *item = lookup_fn(key);
+-      if (!*item)
+-              return -ENOMEM;
+-      return cache_check(detail, &(*item)->h, &mdr->req);
+-}
+-
+-static inline int
+-do_idmap_lookup_nowait(struct ent *(*lookup_fn)(struct ent *),
+-                      struct ent *key, struct cache_detail *detail,
+-                      struct ent **item)
+-{
+-      int ret = -ENOMEM;
+-
+-      *item = lookup_fn(key);
+-      if (!*item)
+-              goto out_err;
+-      ret = -ETIMEDOUT;
+-      if (!test_bit(CACHE_VALID, &(*item)->h.flags)
+-                      || (*item)->h.expiry_time < get_seconds()
+-                      || detail->flush_time > (*item)->h.last_refresh)
+-              goto out_put;
+-      ret = -ENOENT;
+-      if (test_bit(CACHE_NEGATIVE, &(*item)->h.flags))
+-              goto out_put;
+-      return 0;
+-out_put:
+-      cache_put(&(*item)->h, detail);
+-out_err:
+-      *item = NULL;
+-      return ret;
+-}
+-
+ static int
+ idmap_lookup(struct svc_rqst *rqstp,
+               struct ent *(*lookup_fn)(struct ent *), struct ent *key,
+               struct cache_detail *detail, struct ent **item)
+ {
+-      struct idmap_defer_req *mdr;
+       int ret;
+ 
+-      mdr = kzalloc(sizeof(*mdr), GFP_KERNEL);
+-      if (!mdr)
++      *item = lookup_fn(key);
++      if (!*item)
+               return -ENOMEM;
+-      atomic_set(&mdr->count, 1);
+-      init_waitqueue_head(&mdr->waitq);
+-      mdr->req.defer = idmap_defer;
+-      ret = do_idmap_lookup(lookup_fn, key, detail, item, mdr);
+-      if (ret == -EAGAIN) {
+-              wait_event_interruptible_timeout(mdr->waitq,
+-                      test_bit(CACHE_VALID, &(*item)->h.flags), 1 * HZ);
+-              ret = do_idmap_lookup_nowait(lookup_fn, key, detail, item);
++ retry:
++      ret = cache_check(detail, &(*item)->h, &rqstp->rq_chandle);
++
++      if (ret == -ETIMEDOUT) {
++              struct ent *prev_item = *item;
++              *item = lookup_fn(key);
++              if (*item != prev_item)
++                      goto retry;
++              cache_put(&(*item)->h, detail);
+       }
+-      put_mdr(mdr);
+       return ret;
+ }
+