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-rw-r--r--kernel/resource.c61
1 files changed, 49 insertions, 12 deletions
diff --git a/kernel/resource.c b/kernel/resource.c
index 7b36976e5de..798e2fae2a0 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -357,6 +357,32 @@ int __weak page_is_ram(unsigned long pfn)
return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1;
}
+void __weak arch_remove_reservations(struct resource *avail)
+{
+}
+
+static resource_size_t simple_align_resource(void *data,
+ const struct resource *avail,
+ resource_size_t size,
+ resource_size_t align)
+{
+ return avail->start;
+}
+
+static void resource_clip(struct resource *res, resource_size_t min,
+ resource_size_t max)
+{
+ if (res->start < min)
+ res->start = min;
+ if (res->end > max)
+ res->end = max;
+}
+
+static bool resource_contains(struct resource *res1, struct resource *res2)
+{
+ return res1->start <= res2->start && res1->end >= res2->end;
+}
+
/*
* Find empty slot in the resource tree given range and alignment.
*/
@@ -370,8 +396,9 @@ static int find_resource(struct resource *root, struct resource *new,
void *alignf_data)
{
struct resource *this = root->child;
- struct resource tmp = *new;
+ struct resource tmp = *new, avail, alloc;
+ tmp.flags = new->flags;
tmp.start = root->start;
/*
* Skip past an allocated resource that starts at 0, since the assignment
@@ -386,17 +413,22 @@ static int find_resource(struct resource *root, struct resource *new,
tmp.end = this->start - 1;
else
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)
- tmp.start = 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;
+
+ resource_clip(&tmp, min, max);
+ arch_remove_reservations(&tmp);
+
+ /* Check for overflow after ALIGN() */
+ avail = *new;
+ avail.start = ALIGN(tmp.start, align);
+ avail.end = tmp.end;
+ if (avail.start >= tmp.start) {
+ alloc.start = alignf(alignf_data, &avail, size, align);
+ alloc.end = alloc.start + size - 1;
+ if (resource_contains(&avail, &alloc)) {
+ new->start = alloc.start;
+ new->end = alloc.end;
+ return 0;
+ }
}
if (!this)
break;
@@ -428,6 +460,9 @@ int allocate_resource(struct resource *root, struct resource *new,
{
int err;
+ if (!alignf)
+ alignf = simple_align_resource;
+
write_lock(&resource_lock);
err = find_resource(root, new, size, min, max, align, alignf, alignf_data);
if (err >= 0 && __request_resource(root, new))
@@ -453,6 +488,8 @@ static struct resource * __insert_resource(struct resource *parent, struct resou
if (first == parent)
return first;
+ if (WARN_ON(first == new)) /* duplicated insertion */
+ return first;
if ((first->start > new->start) || (first->end < new->end))
break;