resources: fix call to alignf() in allocate_resource()

The second parameter to alignf() in allocate_resource() must
reflect what new resource is attempted to be allocated, else
functions like pcibios_align_resource() (at least on x86) or
pcmcia_align() can't work correctly.

Commit 1e5ad9679016275d422e36b12a98b0927d76f556 broke this by
setting the "new" resource until we're about to return success.
To keep the resource untouched when allocate_resource() fails,
a "tmp" resource is introduced.

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Acked-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 16 insertions, 16 deletions

diff --git a/kernel/resource.c b/kernel/resource.c
index dc15686b7a77..af96c1e4b54b 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -308,37 +308,37 @@ static int find_resource(struct resource *root, struct resource *new,
                          void *alignf_data)
 {
         struct resource *this = root->child;
-        resource_size_t start, end;
+        struct resource tmp = *new;
 
-        start = root->start;
+        tmp.start = root->start;
         /*
          * Skip past an allocated resource that starts at 0, since the assignment
-         * of this->start - 1 to new->end below would cause an underflow.
+         * of this->start - 1 to tmp->end below would cause an underflow.
          */
         if (this && this->start == 0) {
-                start = this->end + 1;
+                tmp.start = this->end + 1;
                 this = this->sibling;
         }
         for(;;) {
                 if (this)
-                        end = this->start - 1;
+                        tmp.end = this->start - 1;
                 else
-                        end = root->end;
-                if (start < min)
-                        start = min;
-                if (end > max)
-                        end = max;
-                start = ALIGN(start, align);
+                        tmp.end = root->end;
+                if (tmp.start < min)
+                        tmp.start = min;
+                if (tmp.end > max)
+                        tmp.end = max;
+                tmp.start = ALIGN(tmp.start, align);
                 if (alignf)
-                        alignf(alignf_data, new, size, align);
-                if (start < end && end - start >= size - 1) {
-                        new->start = start;
-                        new->end = start + size - 1;
+                        alignf(alignf_data, &tmp, size, align);
+                if (tmp.start < tmp.end && tmp.end - tmp.start >= size - 1) {
+                        new->start = tmp.start;
+                        new->end = tmp.start + size - 1;
                         return 0;
                 }
                 if (!this)
                         break;
-                start = this->end + 1;
+                tmp.start = this->end + 1;
                 this = this->sibling;
         }
         return -EBUSY;