diff mbox

[-v12,03/15] resources: Replace registered resource in tree.

Message ID 1340736849-14875-4-git-send-email-yinghai@kernel.org
State Rejected
Headers show

Commit Message

Yinghai Lu June 26, 2012, 6:53 p.m. UTC
We could have one resource inserted in tree at first during probing.

Later we need to put real resource into the tree.

So try to hold the lock to swap them.

-v2: make it more generic to handle old one with children or no parent.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
---
 include/linux/ioport.h |    1 +
 kernel/resource.c      |   25 +++++++++++++++++++++++++
 2 files changed, 26 insertions(+), 0 deletions(-)
diff mbox

Patch

diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index 8292e8b..cbf3480 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -163,6 +163,7 @@  int probe_resource(struct resource *b_res,
 			struct resource *busn_res,
 			resource_size_t needed_size, struct resource **p,
 			int skip_nr, int limit, int flags);
+void replace_resource(struct resource *old_res, struct resource *new_res);
 struct resource *lookup_resource(struct resource *root, resource_size_t start);
 int adjust_resource(struct resource *res, resource_size_t start,
 		    resource_size_t size);
diff --git a/kernel/resource.c b/kernel/resource.c
index d5d9aef..8da0e76 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -1129,6 +1129,31 @@  reduce_needed_size:
 	return ret;
 }
 
+/* replace old with new in the resource tree */
+void replace_resource(struct resource *old, struct resource *new)
+{
+	struct resource *parent, *tmp, *p;
+
+	write_lock(&resource_lock);
+	new->start = old->start;
+	new->end = old->end;
+	new->flags = old->flags;
+
+	p = old->child;
+	while (p) {
+		tmp = p;
+		p = p->sibling;
+		__release_resource(tmp);
+		__request_resource(new, tmp);
+	}
+	parent = old->parent;
+	if (parent) {
+		__release_resource(old);
+		__request_resource(parent, new);
+	}
+	write_unlock(&resource_lock);
+}
+
 /*
  * Managed region resource
  */