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Diffstat (limited to 'kernel/resource.c')
-rw-r--r--kernel/resource.c88
1 files changed, 63 insertions, 25 deletions
diff --git a/kernel/resource.c b/kernel/resource.c
index c9fd26c06345..e4e9bac12e6e 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -341,6 +341,8 @@ static int find_next_iomem_res(resource_size_t start, resource_size_t end,
unsigned long flags, unsigned long desc,
struct resource *res)
{
+ /* Skip children until we find a top level range that matches */
+ bool skip_children = true;
struct resource *p;
if (!res)
@@ -351,7 +353,7 @@ static int find_next_iomem_res(resource_size_t start, resource_size_t end,
read_lock(&resource_lock);
- for_each_resource(&iomem_resource, p, false) {
+ for_each_resource(&iomem_resource, p, skip_children) {
/* If we passed the resource we are looking for, stop */
if (p->start > end) {
p = NULL;
@@ -362,6 +364,12 @@ static int find_next_iomem_res(resource_size_t start, resource_size_t end,
if (p->end < start)
continue;
+ /*
+ * We found a top level range that matches what we are looking
+ * for. Time to start checking children too.
+ */
+ skip_children = false;
+
/* Found a match, break */
if (is_type_match(p, flags, desc))
break;
@@ -561,8 +569,7 @@ static int __region_intersects(struct resource *parent, resource_size_t start,
struct resource res, o;
bool covered;
- res.start = start;
- res.end = start + size - 1;
+ res = DEFINE_RES(start, size, 0);
for (p = parent->child; p ; p = p->sibling) {
if (!resource_intersection(p, &res, &o))
@@ -998,7 +1005,7 @@ void insert_resource_expand_to_fit(struct resource *root, struct resource *new)
* to use this interface. The former are built-in and only the latter,
* CXL, is a module.
*/
-EXPORT_SYMBOL_NS_GPL(insert_resource_expand_to_fit, CXL);
+EXPORT_SYMBOL_NS_GPL(insert_resource_expand_to_fit, "CXL");
/**
* remove_resource - Remove a resource in the resource tree
@@ -1280,8 +1287,9 @@ static int __request_region_locked(struct resource *res, struct resource *parent
* become unavailable to other users. Conflicts are
* not expected. Warn to aid debugging if encountered.
*/
- if (conflict->desc == IORES_DESC_DEVICE_PRIVATE_MEMORY) {
- pr_warn("Unaddressable device %s %pR conflicts with %pR",
+ if (parent == &iomem_resource &&
+ conflict->desc == IORES_DESC_DEVICE_PRIVATE_MEMORY) {
+ pr_warn("Unaddressable device %s %pR conflicts with %pR\n",
conflict->name, conflict, res);
}
if (conflict != parent) {
@@ -1388,6 +1396,47 @@ void __release_region(struct resource *parent, resource_size_t start,
EXPORT_SYMBOL(__release_region);
#ifdef CONFIG_MEMORY_HOTREMOVE
+static void append_child_to_parent(struct resource *new_parent, struct resource *new_child)
+{
+ struct resource *child;
+
+ child = new_parent->child;
+ if (child) {
+ while (child->sibling)
+ child = child->sibling;
+ child->sibling = new_child;
+ } else {
+ new_parent->child = new_child;
+ }
+ new_child->parent = new_parent;
+ new_child->sibling = NULL;
+}
+
+/*
+ * Reparent all child resources that no longer belong to "low" after a split to
+ * "high". Note that "high" does not have any children, because "low" is the
+ * original resource and "high" is a new resource. Treat "low" as the original
+ * resource being split and defer its range adjustment to __adjust_resource().
+ */
+static void reparent_children_after_split(struct resource *low,
+ struct resource *high,
+ resource_size_t split_addr)
+{
+ struct resource *child, *next, **p;
+
+ p = &low->child;
+ while ((child = *p)) {
+ next = child->sibling;
+ if (child->start > split_addr) {
+ /* unlink child */
+ *p = next;
+ append_child_to_parent(high, child);
+ } else {
+ p = &child->sibling;
+ }
+ }
+}
+
/**
* release_mem_region_adjustable - release a previously reserved memory region
* @start: resource start address
@@ -1397,15 +1446,13 @@ EXPORT_SYMBOL(__release_region);
* is released from a currently busy memory resource. The requested region
* must either match exactly or fit into a single busy resource entry. In
* the latter case, the remaining resource is adjusted accordingly.
- * Existing children of the busy memory resource must be immutable in the
- * request.
*
* Note:
* - Additional release conditions, such as overlapping region, can be
* supported after they are confirmed as valid cases.
- * - When a busy memory resource gets split into two entries, the code
- * assumes that all children remain in the lower address entry for
- * simplicity. Enhance this logic when necessary.
+ * - When a busy memory resource gets split into two entries, its children are
+ * reassigned to the correct parent based on their range. If a child memory
+ * resource overlaps with more than one parent, enhance the logic as needed.
*/
void release_mem_region_adjustable(resource_size_t start, resource_size_t size)
{
@@ -1482,6 +1529,7 @@ retry:
new_res->parent = res->parent;
new_res->sibling = res->sibling;
new_res->child = NULL;
+ reparent_children_after_split(res, new_res, end);
if (WARN_ON_ONCE(__adjust_resource(res, res->start,
start - res->start)))
@@ -1683,8 +1731,7 @@ void __devm_release_region(struct device *dev, struct resource *parent,
{
struct region_devres match_data = { parent, start, n };
- __release_region(parent, start, n);
- WARN_ON(devres_destroy(dev, devm_region_release, devm_region_match,
+ WARN_ON(devres_release(dev, devm_region_release, devm_region_match,
&match_data));
}
EXPORT_SYMBOL(__devm_release_region);
@@ -1715,18 +1762,13 @@ static int __init reserve_setup(char *str)
* I/O port space; otherwise assume it's memory.
*/
if (io_start < 0x10000) {
- res->flags = IORESOURCE_IO;
+ *res = DEFINE_RES_IO_NAMED(io_start, io_num, "reserved");
parent = &ioport_resource;
} else {
- res->flags = IORESOURCE_MEM;
+ *res = DEFINE_RES_MEM_NAMED(io_start, io_num, "reserved");
parent = &iomem_resource;
}
- res->name = "reserved";
- res->start = io_start;
- res->end = io_start + io_num - 1;
res->flags |= IORESOURCE_BUSY;
- res->desc = IORES_DESC_NONE;
- res->child = NULL;
if (request_resource(parent, res) == 0)
reserved = x+1;
}
@@ -1976,11 +2018,7 @@ get_free_mem_region(struct device *dev, struct resource *base,
*/
revoke_iomem(res);
} else {
- res->start = addr;
- res->end = addr + size - 1;
- res->name = name;
- res->desc = desc;
- res->flags = IORESOURCE_MEM;
+ *res = DEFINE_RES_NAMED_DESC(addr, size, name, IORESOURCE_MEM, desc);
/*
* Only succeed if the resource hosts an exclusive