FS-Cache: Wrap checks on object state

Wrap checks on object state (mostly outside of fs/fscache/object.c) with
inline functions so that the mechanism can be replaced.

Some of the state checks within object.c are left as-is as they will be
replaced.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Milosz Tanski <milosz@adfin.com>
Acked-by: Jeff Layton <jlayton@redhat.com>

6 files changed, 40 insertions, 21 deletions

diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c
index 07cbd447861e..01979a3f5121 100644
--- a/fs/cachefiles/namei.c
+++ b/fs/cachefiles/namei.c
@@ -130,7 +130,7 @@ found_dentry:
                fscache_object_states[object->fscache.state],
                dentry);
 
-        if (object->fscache.state < FSCACHE_OBJECT_DYING) {
+        if (fscache_object_is_live(&object->fscache)) {
                 printk(KERN_ERR "\n");
                 printk(KERN_ERR "CacheFiles: Error:"
                        " Can't preemptively bury live object\n");
@@ -192,7 +192,7 @@ try_again:
         /* an old object from a previous incarnation is hogging the slot - we
          * need to wait for it to be destroyed */
 wait_for_old_object:
-        if (xobject->fscache.state < FSCACHE_OBJECT_DYING) {
+        if (fscache_object_is_live(&object->fscache)) {
                 printk(KERN_ERR "\n");
                 printk(KERN_ERR "CacheFiles: Error:"
                        " Unexpected object collision\n");
diff --git a/fs/fscache/cache.c b/fs/fscache/cache.c
index b52aed1dca97..129ea537f023 100644
--- a/fs/fscache/cache.c
+++ b/fs/fscache/cache.c
@@ -115,7 +115,7 @@ struct fscache_cache *fscache_select_cache_for_object(
                                      struct fscache_object, cookie_link);
 
                 cache = object->cache;
-                if (object->state >= FSCACHE_OBJECT_DYING ||
+                if (fscache_object_is_dying(object) ||
                     test_bit(FSCACHE_IOERROR, &cache->flags))
                         cache = NULL;
 
diff --git a/fs/fscache/cookie.c b/fs/fscache/cookie.c
index e2cba1f60c21..a5f36c921e91 100644
--- a/fs/fscache/cookie.c
+++ b/fs/fscache/cookie.c
@@ -285,7 +285,7 @@ static int fscache_alloc_object(struct fscache_cache *cache,
 
 object_already_extant:
         ret = -ENOBUFS;
-        if (object->state >= FSCACHE_OBJECT_DYING) {
+        if (fscache_object_is_dead(object)) {
                 spin_unlock(&cookie->lock);
                 goto error;
         }
@@ -321,7 +321,7 @@ static int fscache_attach_object(struct fscache_cookie *cookie,
         ret = -EEXIST;
         hlist_for_each_entry(p, &cookie->backing_objects, cookie_link) {
                 if (p->cache == object->cache) {
-                        if (p->state >= FSCACHE_OBJECT_DYING)
+                        if (fscache_object_is_dying(p))
                                 ret = -ENOBUFS;
                         goto cant_attach_object;
                 }
@@ -332,7 +332,7 @@ static int fscache_attach_object(struct fscache_cookie *cookie,
         hlist_for_each_entry(p, &cookie->parent->backing_objects,
                              cookie_link) {
                 if (p->cache == object->cache) {
-                        if (p->state >= FSCACHE_OBJECT_DYING) {
+                        if (fscache_object_is_dying(p)) {
                                 ret = -ENOBUFS;
                                 spin_unlock(&cookie->parent->lock);
                                 goto cant_attach_object;
@@ -400,7 +400,7 @@ void __fscache_invalidate(struct fscache_cookie *cookie)
                         object = hlist_entry(cookie->backing_objects.first,
                                              struct fscache_object,
                                              cookie_link);
-                        if (object->state < FSCACHE_OBJECT_DYING)
+                        if (fscache_object_is_live(object))
                                 fscache_raise_event(
                                         object, FSCACHE_OBJECT_EV_INVALIDATE);
                 }
diff --git a/fs/fscache/object.c b/fs/fscache/object.c
index 0133699f74ee..863f6873c0f0 100644
--- a/fs/fscache/object.c
+++ b/fs/fscache/object.c
@@ -457,10 +457,10 @@ static void fscache_initialise_object(struct fscache_object *object)
                 spin_lock_nested(&parent->lock, 1);
                 _debug("parent %s", fscache_object_states[parent->state]);
 
-                if (parent->state >= FSCACHE_OBJECT_DYING) {
+                if (fscache_object_is_dying(parent)) {
                         _debug("bad parent");
                         set_bit(FSCACHE_OBJECT_EV_WITHDRAW, &object->events);
-                } else if (parent->state < FSCACHE_OBJECT_AVAILABLE) {
+                } else if (!fscache_object_is_available(parent)) {
                         _debug("wait");
 
                         /* we may get woken up in this state by child objects
@@ -517,9 +517,9 @@ static void fscache_lookup_object(struct fscache_object *object)
         ASSERTCMP(parent->n_obj_ops, >, 0);
 
         /* make sure the parent is still available */
-        ASSERTCMP(parent->state, >=, FSCACHE_OBJECT_AVAILABLE);
+        ASSERT(fscache_object_is_available(parent));
 
-        if (parent->state >= FSCACHE_OBJECT_DYING ||
+        if (fscache_object_is_dying(parent) ||
             test_bit(FSCACHE_IOERROR, &object->cache->flags)) {
                 _debug("unavailable");
                 set_bit(FSCACHE_OBJECT_EV_WITHDRAW, &object->events);
diff --git a/fs/fscache/operation.c b/fs/fscache/operation.c
index 762a9ec4ffa4..ccf02194e7a6 100644
--- a/fs/fscache/operation.c
+++ b/fs/fscache/operation.c
@@ -35,7 +35,7 @@ void fscache_enqueue_operation(struct fscache_operation *op)
 
         ASSERT(list_empty(&op->pend_link));
         ASSERT(op->processor != NULL);
-        ASSERTCMP(op->object->state, >=, FSCACHE_OBJECT_AVAILABLE);
+        ASSERT(fscache_object_is_available(op->object));
         ASSERTCMP(atomic_read(&op->usage), >, 0);
         ASSERTCMP(op->state, ==, FSCACHE_OP_ST_IN_PROGRESS);
 
diff --git a/include/linux/fscache-cache.h b/include/linux/fscache-cache.h
index 9b9c1de4a460..c5f92347cbf8 100644
--- a/include/linux/fscache-cache.h
+++ b/include/linux/fscache-cache.h
@@ -417,15 +417,6 @@ struct fscache_object {
 
 extern const char *fscache_object_states[];
 
-#define fscache_object_is_active(obj)                         \
-        (!test_bit(FSCACHE_IOERROR, &(obj)->cache->flags) &&  \
-         (obj)->state >= FSCACHE_OBJECT_AVAILABLE &&          \
-         (obj)->state < FSCACHE_OBJECT_DYING)
-
-#define fscache_object_is_dead(obj)                             \
-        (test_bit(FSCACHE_IOERROR, &(obj)->cache->flags) &&     \
-         (obj)->state >= FSCACHE_OBJECT_DYING)
-
 extern void fscache_object_init(struct fscache_object *, struct fscache_cookie *,
                                 struct fscache_cache *);
 
@@ -438,6 +429,34 @@ extern void fscache_object_destroy(struct fscache_object *object);
 #define fscache_object_destroy(object) do {} while(0)
 #endif
 
+static inline bool fscache_object_is_live(struct fscache_object *object)
+{
+        return object->state < FSCACHE_OBJECT_DYING;
+}
+
+static inline bool fscache_object_is_dying(struct fscache_object *object)
+{
+        return !fscache_object_is_live(object);
+}
+
+static inline bool fscache_object_is_available(struct fscache_object *object)
+{
+        return object->state >= FSCACHE_OBJECT_AVAILABLE;
+}
+
+static inline bool fscache_object_is_active(struct fscache_object *object)
+{
+        return fscache_object_is_available(object) &&
+                fscache_object_is_live(object) &&
+                !test_bit(FSCACHE_IOERROR, &object->cache->flags);
+}
+
+static inline bool fscache_object_is_dead(struct fscache_object *object)
+{
+        return fscache_object_is_dying(object) &&
+                test_bit(FSCACHE_IOERROR, &object->cache->flags);
+}
+
 /**
  * fscache_object_destroyed - Note destruction of an object in a cache
  * @cache: The cache from which the object came