diff options
author | Matthew Wilcox <matthew@wil.cx> | 2006-06-30 02:31:24 -0700 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2006-09-26 17:43:52 -0700 |
commit | d33b6fba2c4350651f3f61ff2ab858a2f116e9a4 (patch) | |
tree | fa4fa45fd6cc3bf177e13c2e9544b3e8134e1456 /kernel | |
parent | b278240839e20fa9384ea430df463b367b90e04e (diff) | |
download | op-kernel-dev-d33b6fba2c4350651f3f61ff2ab858a2f116e9a4.zip op-kernel-dev-d33b6fba2c4350651f3f61ff2ab858a2f116e9a4.tar.gz |
Resources: insert identical resources above existing resources
If you have two resources which aree exactly the same size,
insert_resource() currently inserts the new one below the existing one.
This is wrong because there's no way to insert a resource of the same size
above an existing one.
I took this opportunity to rewrite the initial loop to be a for-loop
instead of a goto-loop and fix the documentation.
Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/resource.c | 32 |
1 files changed, 16 insertions, 16 deletions
diff --git a/kernel/resource.c b/kernel/resource.c index 4628643..9db38a1 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -344,12 +344,11 @@ EXPORT_SYMBOL(allocate_resource); * * Returns 0 on success, -EBUSY if the resource can't be inserted. * - * This function is equivalent of request_resource when no conflict + * This function is equivalent to request_resource when no conflict * happens. If a conflict happens, and the conflicting resources * entirely fit within the range of the new resource, then the new - * resource is inserted and the conflicting resources become childs of - * the new resource. Otherwise the new resource becomes the child of - * the conflicting resource + * resource is inserted and the conflicting resources become children of + * the new resource. */ int insert_resource(struct resource *parent, struct resource *new) { @@ -357,20 +356,21 @@ int insert_resource(struct resource *parent, struct resource *new) struct resource *first, *next; write_lock(&resource_lock); - begin: - result = 0; - first = __request_resource(parent, new); - if (!first) - goto out; - result = -EBUSY; - if (first == parent) - goto out; + for (;; parent = first) { + result = 0; + first = __request_resource(parent, new); + if (!first) + goto out; - /* Resource fully contained by the clashing resource? Recurse into it */ - if (first->start <= new->start && first->end >= new->end) { - parent = first; - goto begin; + result = -EBUSY; + if (first == parent) + goto out; + + if ((first->start > new->start) || (first->end < new->end)) + break; + if ((first->start == new->start) && (first->end == new->end)) + break; } for (next = first; ; next = next->sibling) { |