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authorLinus Torvalds2011-07-31 14:30:59 -1000
committerLinus Torvalds2011-07-31 14:30:59 -1000
commit968e75fc13b6d582f42ce44172e13ba58157e11f (patch)
tree306eacdf2815f8a49b47228c3b50e7a6083ef7d4 /kernel
parenta00ed25cce6fe856388f89c7cd40da0eee7666a6 (diff)
parentd3690f8b713f9710e68214ca38fb8b07b587a2a7 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k: m68k/math-emu: Remove unnecessary code m68k/math-emu: Remove commented out old code m68k: Kill warning in setup_arch() when compiling for Sun3 m68k/atari: Prefix GPIO_{IN,OUT} with CODEC_ sparc: iounmap() and *_free_coherent() - Use lookup_resource() m68k/atari: Reserve some ST-RAM early on for device buffer use m68k/amiga: Chip RAM - Use lookup_resource() resources: Add lookup_resource() sparc: _sparc_find_resource() should check for exact matches m68k/amiga: Chip RAM - Offset resource end by CHIP_PHYSADDR m68k/amiga: Chip RAM - Use resource_size() to fix off-by-one error m68k/amiga: Chip RAM - Change chipavail to an atomic_t m68k/amiga: Chip RAM - Always allocate from the start of memory m68k/amiga: Chip RAM - Convert from printk() to pr_*() m68k/amiga: Chip RAM - Use tabs for indentation
Diffstat (limited to 'kernel')
-rw-r--r--kernel/resource.c21
1 files changed, 21 insertions, 0 deletions
diff --git a/kernel/resource.c b/kernel/resource.c
index 3ff40178dce7..3b3cedc52592 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -553,6 +553,27 @@ int allocate_resource(struct resource *root, struct resource *new,
EXPORT_SYMBOL(allocate_resource);
+/**
+ * lookup_resource - find an existing resource by a resource start address
+ * @root: root resource descriptor
+ * @start: resource start address
+ *
+ * Returns a pointer to the resource if found, NULL otherwise
+ */
+struct resource *lookup_resource(struct resource *root, resource_size_t start)
+{
+ struct resource *res;
+
+ read_lock(&resource_lock);
+ for (res = root->child; res; res = res->sibling) {
+ if (res->start == start)
+ break;
+ }
+ read_unlock(&resource_lock);
+
+ return res;
+}
+
/*
* Insert a resource into the resource tree. If successful, return NULL,
* otherwise return the conflicting resource (compare to __request_resource())