1 files changed, 2 insertions, 384 deletions

diff --git a/drivers/staging/lustre/lustre/lov/lovsub_lock.c b/drivers/staging/lustre/lustre/lov/lovsub_lock.c
index 3bb0c9068a90..e92edfb618b7 100644
--- a/drivers/staging/lustre/lustre/lov/lovsub_lock.c
+++ b/drivers/staging/lustre/lustre/lov/lovsub_lock.c
@@ -62,391 +62,8 @@ static void lovsub_lock_fini(const struct lu_env *env,
 	kmem_cache_free(lovsub_lock_kmem, lsl);
 }
 
-static void lovsub_parent_lock(const struct lu_env *env, struct lov_lock *lov)
-{
-	struct cl_lock *parent;
-
-	parent = lov->lls_cl.cls_lock;
-	cl_lock_get(parent);
-	lu_ref_add(&parent->cll_reference, "lovsub-parent", current);
-	cl_lock_mutex_get(env, parent);
-}
-
-static void lovsub_parent_unlock(const struct lu_env *env, struct lov_lock *lov)
-{
-	struct cl_lock *parent;
-
-	parent = lov->lls_cl.cls_lock;
-	cl_lock_mutex_put(env, lov->lls_cl.cls_lock);
-	lu_ref_del(&parent->cll_reference, "lovsub-parent", current);
-	cl_lock_put(env, parent);
-}
-
-/**
- * Implements cl_lock_operations::clo_state() method for lovsub layer, which
- * method is called whenever sub-lock state changes. Propagates state change
- * to the top-locks.
- */
-static void lovsub_lock_state(const struct lu_env *env,
-			      const struct cl_lock_slice *slice,
-			      enum cl_lock_state state)
-{
-	struct lovsub_lock   *sub = cl2lovsub_lock(slice);
-	struct lov_lock_link *scan;
-
-	LASSERT(cl_lock_is_mutexed(slice->cls_lock));
-
-	list_for_each_entry(scan, &sub->lss_parents, lll_list) {
-		struct lov_lock *lov    = scan->lll_super;
-		struct cl_lock  *parent = lov->lls_cl.cls_lock;
-
-		if (sub->lss_active != parent) {
-			lovsub_parent_lock(env, lov);
-			cl_lock_signal(env, parent);
-			lovsub_parent_unlock(env, lov);
-		}
-	}
-}
-
-/**
- * Implementation of cl_lock_operation::clo_weigh() estimating lock weight by
- * asking parent lock.
- */
-static unsigned long lovsub_lock_weigh(const struct lu_env *env,
-				       const struct cl_lock_slice *slice)
-{
-	struct lovsub_lock *lock = cl2lovsub_lock(slice);
-	struct lov_lock    *lov;
-	unsigned long       dumbbell;
-
-	LASSERT(cl_lock_is_mutexed(slice->cls_lock));
-
-	if (!list_empty(&lock->lss_parents)) {
-		/*
-		 * It is not clear whether all parents have to be asked and
-		 * their estimations summed, or it is enough to ask one. For
-		 * the current usages, one is always enough.
-		 */
-		lov = container_of(lock->lss_parents.next,
-				   struct lov_lock_link, lll_list)->lll_super;
-
-		lovsub_parent_lock(env, lov);
-		dumbbell = cl_lock_weigh(env, lov->lls_cl.cls_lock);
-		lovsub_parent_unlock(env, lov);
-	} else
-		dumbbell = 0;
-
-	return dumbbell;
-}
-
-/**
- * Maps start/end offsets within a stripe, to offsets within a file.
- */
-static void lovsub_lock_descr_map(const struct cl_lock_descr *in,
-				  struct lov_object *lov,
-				  int stripe, struct cl_lock_descr *out)
-{
-	pgoff_t size; /* stripe size in pages */
-	pgoff_t skip; /* how many pages in every stripe are occupied by
-		       * "other" stripes
-		       */
-	pgoff_t start;
-	pgoff_t end;
-
-	start = in->cld_start;
-	end   = in->cld_end;
-
-	if (lov->lo_lsm->lsm_stripe_count > 1) {
-		size = cl_index(lov2cl(lov), lov->lo_lsm->lsm_stripe_size);
-		skip = (lov->lo_lsm->lsm_stripe_count - 1) * size;
-
-		/* XXX overflow check here? */
-		start += start/size * skip + stripe * size;
-
-		if (end != CL_PAGE_EOF) {
-			end += end/size * skip + stripe * size;
-			/*
-			 * And check for overflow...
-			 */
-			if (end < in->cld_end)
-				end = CL_PAGE_EOF;
-		}
-	}
-	out->cld_start = start;
-	out->cld_end   = end;
-}
-
-/**
- * Adjusts parent lock extent when a sub-lock is attached to a parent. This is
- * called in two ways:
- *
- *     - as part of receive call-back, when server returns granted extent to
- *       the client, and
- *
- *     - when top-lock finds existing sub-lock in the cache.
- *
- * Note, that lock mode is not propagated to the parent: i.e., if CLM_READ
- * top-lock matches CLM_WRITE sub-lock, top-lock is still CLM_READ.
- */
-int lov_sublock_modify(const struct lu_env *env, struct lov_lock *lov,
-		       struct lovsub_lock *sublock,
-		       const struct cl_lock_descr *d, int idx)
-{
-	struct cl_lock       *parent;
-	struct lovsub_object *subobj;
-	struct cl_lock_descr *pd;
-	struct cl_lock_descr *parent_descr;
-	int		   result;
-
-	parent       = lov->lls_cl.cls_lock;
-	parent_descr = &parent->cll_descr;
-	LASSERT(cl_lock_mode_match(d->cld_mode, parent_descr->cld_mode));
-
-	subobj = cl2lovsub(sublock->lss_cl.cls_obj);
-	pd     = &lov_env_info(env)->lti_ldescr;
-
-	pd->cld_obj  = parent_descr->cld_obj;
-	pd->cld_mode = parent_descr->cld_mode;
-	pd->cld_gid  = parent_descr->cld_gid;
-	lovsub_lock_descr_map(d, subobj->lso_super, subobj->lso_index, pd);
-	lov->lls_sub[idx].sub_got = *d;
-	/*
-	 * Notify top-lock about modification, if lock description changes
-	 * materially.
-	 */
-	if (!cl_lock_ext_match(parent_descr, pd))
-		result = cl_lock_modify(env, parent, pd);
-	else
-		result = 0;
-	return result;
-}
-
-static int lovsub_lock_modify(const struct lu_env *env,
-			      const struct cl_lock_slice *s,
-			      const struct cl_lock_descr *d)
-{
-	struct lovsub_lock   *lock   = cl2lovsub_lock(s);
-	struct lov_lock_link *scan;
-	struct lov_lock      *lov;
-	int result		   = 0;
-
-	LASSERT(cl_lock_mode_match(d->cld_mode,
-				   s->cls_lock->cll_descr.cld_mode));
-	list_for_each_entry(scan, &lock->lss_parents, lll_list) {
-		int rc;
-
-		lov = scan->lll_super;
-		lovsub_parent_lock(env, lov);
-		rc = lov_sublock_modify(env, lov, lock, d, scan->lll_idx);
-		lovsub_parent_unlock(env, lov);
-		result = result ?: rc;
-	}
-	return result;
-}
-
-static int lovsub_lock_closure(const struct lu_env *env,
-			       const struct cl_lock_slice *slice,
-			       struct cl_lock_closure *closure)
-{
-	struct lovsub_lock   *sub;
-	struct cl_lock       *parent;
-	struct lov_lock_link *scan;
-	int		   result;
-
-	LASSERT(cl_lock_is_mutexed(slice->cls_lock));
-
-	sub    = cl2lovsub_lock(slice);
-	result = 0;
-
-	list_for_each_entry(scan, &sub->lss_parents, lll_list) {
-		parent = scan->lll_super->lls_cl.cls_lock;
-		result = cl_lock_closure_build(env, parent, closure);
-		if (result != 0)
-			break;
-	}
-	return result;
-}
-
-/**
- * A helper function for lovsub_lock_delete() that deals with a given parent
- * top-lock.
- */
-static int lovsub_lock_delete_one(const struct lu_env *env,
-				  struct cl_lock *child, struct lov_lock *lov)
-{
-	struct cl_lock *parent;
-	int	     result;
-
-	parent = lov->lls_cl.cls_lock;
-	if (parent->cll_error)
-		return 0;
-
-	result = 0;
-	switch (parent->cll_state) {
-	case CLS_ENQUEUED:
-		/* See LU-1355 for the case that a glimpse lock is
-		 * interrupted by signal
-		 */
-		LASSERT(parent->cll_flags & CLF_CANCELLED);
-		break;
-	case CLS_QUEUING:
-	case CLS_FREEING:
-		cl_lock_signal(env, parent);
-		break;
-	case CLS_INTRANSIT:
-		/*
-		 * Here lies a problem: a sub-lock is canceled while top-lock
-		 * is being unlocked. Top-lock cannot be moved into CLS_NEW
-		 * state, because unlocking has to succeed eventually by
-		 * placing lock into CLS_CACHED (or failing it), see
-		 * cl_unuse_try(). Nor can top-lock be left in CLS_CACHED
-		 * state, because lov maintains an invariant that all
-		 * sub-locks exist in CLS_CACHED (this allows cached top-lock
-		 * to be reused immediately). Nor can we wait for top-lock
-		 * state to change, because this can be synchronous to the
-		 * current thread.
-		 *
-		 * We know for sure that lov_lock_unuse() will be called at
-		 * least one more time to finish un-using, so leave a mark on
-		 * the top-lock, that will be seen by the next call to
-		 * lov_lock_unuse().
-		 */
-		if (cl_lock_is_intransit(parent))
-			lov->lls_cancel_race = 1;
-		break;
-	case CLS_CACHED:
-		/*
-		 * if a sub-lock is canceled move its top-lock into CLS_NEW
-		 * state to preserve an invariant that a top-lock in
-		 * CLS_CACHED is immediately ready for re-use (i.e., has all
-		 * sub-locks), and so that next attempt to re-use the top-lock
-		 * enqueues missing sub-lock.
-		 */
-		cl_lock_state_set(env, parent, CLS_NEW);
-		/* fall through */
-	case CLS_NEW:
-		/*
-		 * if last sub-lock is canceled, destroy the top-lock (which
-		 * is now `empty') proactively.
-		 */
-		if (lov->lls_nr_filled == 0) {
-			/* ... but unfortunately, this cannot be done easily,
-			 * as cancellation of a top-lock might acquire mutices
-			 * of its other sub-locks, violating lock ordering,
-			 * see cl_lock_{cancel,delete}() preconditions.
-			 *
-			 * To work around this, the mutex of this sub-lock is
-			 * released, top-lock is destroyed, and sub-lock mutex
-			 * acquired again. The list of parents has to be
-			 * re-scanned from the beginning after this.
-			 *
-			 * Only do this if no mutices other than on @child and
-			 * @parent are held by the current thread.
-			 *
-			 * TODO: The lock modal here is too complex, because
-			 * the lock may be canceled and deleted by voluntarily:
-			 *    cl_lock_request
-			 *      -> osc_lock_enqueue_wait
-			 *	-> osc_lock_cancel_wait
-			 *	  -> cl_lock_delete
-			 *	    -> lovsub_lock_delete
-			 *	      -> cl_lock_cancel/delete
-			 *		-> ...
-			 *
-			 * The better choice is to spawn a kernel thread for
-			 * this purpose. -jay
-			 */
-			if (cl_lock_nr_mutexed(env) == 2) {
-				cl_lock_mutex_put(env, child);
-				cl_lock_cancel(env, parent);
-				cl_lock_delete(env, parent);
-				result = 1;
-			}
-		}
-		break;
-	case CLS_HELD:
-		CL_LOCK_DEBUG(D_ERROR, env, parent, "Delete CLS_HELD lock\n");
-	default:
-		CERROR("Impossible state: %d\n", parent->cll_state);
-		LBUG();
-		break;
-	}
-
-	return result;
-}
-
-/**
- * An implementation of cl_lock_operations::clo_delete() method. This is
- * invoked in "bottom-to-top" delete, when lock destruction starts from the
- * sub-lock (e.g, as a result of ldlm lock LRU policy).
- */
-static void lovsub_lock_delete(const struct lu_env *env,
-			       const struct cl_lock_slice *slice)
-{
-	struct cl_lock     *child = slice->cls_lock;
-	struct lovsub_lock *sub   = cl2lovsub_lock(slice);
-	int restart;
-
-	LASSERT(cl_lock_is_mutexed(child));
-
-	/*
-	 * Destruction of a sub-lock might take multiple iterations, because
-	 * when the last sub-lock of a given top-lock is deleted, top-lock is
-	 * canceled proactively, and this requires to release sub-lock
-	 * mutex. Once sub-lock mutex has been released, list of its parents
-	 * has to be re-scanned from the beginning.
-	 */
-	do {
-		struct lov_lock      *lov;
-		struct lov_lock_link *scan;
-		struct lov_lock_link *temp;
-		struct lov_lock_sub  *subdata;
-
-		restart = 0;
-		list_for_each_entry_safe(scan, temp,
-					 &sub->lss_parents, lll_list) {
-			lov     = scan->lll_super;
-			subdata = &lov->lls_sub[scan->lll_idx];
-			lovsub_parent_lock(env, lov);
-			subdata->sub_got = subdata->sub_descr;
-			lov_lock_unlink(env, scan, sub);
-			restart = lovsub_lock_delete_one(env, child, lov);
-			lovsub_parent_unlock(env, lov);
-
-			if (restart) {
-				cl_lock_mutex_get(env, child);
-				break;
-			}
-	       }
-	} while (restart);
-}
-
-static int lovsub_lock_print(const struct lu_env *env, void *cookie,
-			     lu_printer_t p, const struct cl_lock_slice *slice)
-{
-	struct lovsub_lock   *sub = cl2lovsub_lock(slice);
-	struct lov_lock      *lov;
-	struct lov_lock_link *scan;
-
-	list_for_each_entry(scan, &sub->lss_parents, lll_list) {
-		lov = scan->lll_super;
-		(*p)(env, cookie, "[%d %p ", scan->lll_idx, lov);
-		if (lov)
-			cl_lock_descr_print(env, cookie, p,
-					    &lov->lls_cl.cls_lock->cll_descr);
-		(*p)(env, cookie, "] ");
-	}
-	return 0;
-}
-
 static const struct cl_lock_operations lovsub_lock_ops = {
 	.clo_fini    = lovsub_lock_fini,
-	.clo_state   = lovsub_lock_state,
-	.clo_delete  = lovsub_lock_delete,
-	.clo_modify  = lovsub_lock_modify,
-	.clo_closure = lovsub_lock_closure,
-	.clo_weigh   = lovsub_lock_weigh,
-	.clo_print   = lovsub_lock_print
 };
 
 int lovsub_lock_init(const struct lu_env *env, struct cl_object *obj,
@@ -460,8 +77,9 @@ int lovsub_lock_init(const struct lu_env *env, struct cl_object *obj,
 		INIT_LIST_HEAD(&lsk->lss_parents);
 		cl_lock_slice_add(lock, &lsk->lss_cl, obj, &lovsub_lock_ops);
 		result = 0;
-	} else
+	} else {
 		result = -ENOMEM;
+	}
 	return result;
 }