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-rw-r--r--kernel/resource.c229
1 files changed, 220 insertions, 9 deletions
diff --git a/kernel/resource.c b/kernel/resource.c
index 3c2237ac32db..19f2357dfda3 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -22,6 +22,7 @@
#include <linux/device.h>
#include <linux/pfn.h>
#include <linux/mm.h>
+#include <linux/resource_ext.h>
#include <asm/io.h>
@@ -59,10 +60,12 @@ static DEFINE_RWLOCK(resource_lock);
static struct resource *bootmem_resource_free;
static DEFINE_SPINLOCK(bootmem_resource_lock);
-static void *r_next(struct seq_file *m, void *v, loff_t *pos)
+static struct resource *next_resource(struct resource *p, bool sibling_only)
{
- struct resource *p = v;
- (*pos)++;
+ /* Caller wants to traverse through siblings only */
+ if (sibling_only)
+ return p->sibling;
+
if (p->child)
return p->child;
while (!p->sibling && p->parent)
@@ -70,6 +73,13 @@ static void *r_next(struct seq_file *m, void *v, loff_t *pos)
return p->sibling;
}
+static void *r_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct resource *p = v;
+ (*pos)++;
+ return (void *)next_resource(p, false);
+}
+
#ifdef CONFIG_PROC_FS
enum { MAX_IORES_LEVEL = 5 };
@@ -322,16 +332,19 @@ int release_resource(struct resource *old)
EXPORT_SYMBOL(release_resource);
-#if !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
/*
- * Finds the lowest memory reosurce exists within [res->start.res->end)
+ * Finds the lowest iomem reosurce exists with-in [res->start.res->end)
* the caller must specify res->start, res->end, res->flags and "name".
* If found, returns 0, res is overwritten, if not found, returns -1.
+ * This walks through whole tree and not just first level children
+ * until and unless first_level_children_only is true.
*/
-static int find_next_system_ram(struct resource *res, char *name)
+static int find_next_iomem_res(struct resource *res, char *name,
+ bool first_level_children_only)
{
resource_size_t start, end;
struct resource *p;
+ bool sibling_only = false;
BUG_ON(!res);
@@ -339,9 +352,12 @@ static int find_next_system_ram(struct resource *res, char *name)
end = res->end;
BUG_ON(start >= end);
+ if (first_level_children_only)
+ sibling_only = true;
+
read_lock(&resource_lock);
- for (p = iomem_resource.child; p ; p = p->sibling) {
- /* system ram is just marked as IORESOURCE_MEM */
+
+ for (p = iomem_resource.child; p; p = next_resource(p, sibling_only)) {
if (p->flags != res->flags)
continue;
if (name && strcmp(p->name, name))
@@ -353,6 +369,7 @@ static int find_next_system_ram(struct resource *res, char *name)
if ((p->end >= start) && (p->start < end))
break;
}
+
read_unlock(&resource_lock);
if (!p)
return -1;
@@ -365,6 +382,70 @@ static int find_next_system_ram(struct resource *res, char *name)
}
/*
+ * Walks through iomem resources and calls func() with matching resource
+ * ranges. This walks through whole tree and not just first level children.
+ * All the memory ranges which overlap start,end and also match flags and
+ * name are valid candidates.
+ *
+ * @name: name of resource
+ * @flags: resource flags
+ * @start: start addr
+ * @end: end addr
+ */
+int walk_iomem_res(char *name, unsigned long flags, u64 start, u64 end,
+ void *arg, int (*func)(u64, u64, void *))
+{
+ struct resource res;
+ u64 orig_end;
+ int ret = -1;
+
+ res.start = start;
+ res.end = end;
+ res.flags = flags;
+ orig_end = res.end;
+ while ((res.start < res.end) &&
+ (!find_next_iomem_res(&res, name, false))) {
+ ret = (*func)(res.start, res.end, arg);
+ if (ret)
+ break;
+ res.start = res.end + 1;
+ res.end = orig_end;
+ }
+ return ret;
+}
+
+/*
+ * This function calls callback against all memory range of "System RAM"
+ * which are marked as IORESOURCE_MEM and IORESOUCE_BUSY.
+ * Now, this function is only for "System RAM". This function deals with
+ * full ranges and not pfn. If resources are not pfn aligned, dealing
+ * with pfn can truncate ranges.
+ */
+int walk_system_ram_res(u64 start, u64 end, void *arg,
+ int (*func)(u64, u64, void *))
+{
+ struct resource res;
+ u64 orig_end;
+ int ret = -1;
+
+ res.start = start;
+ res.end = end;
+ res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+ orig_end = res.end;
+ while ((res.start < res.end) &&
+ (!find_next_iomem_res(&res, "System RAM", true))) {
+ ret = (*func)(res.start, res.end, arg);
+ if (ret)
+ break;
+ res.start = res.end + 1;
+ res.end = orig_end;
+ }
+ return ret;
+}
+
+#if !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
+
+/*
* This function calls callback against all memory range of "System RAM"
* which are marked as IORESOURCE_MEM and IORESOUCE_BUSY.
* Now, this function is only for "System RAM".
@@ -382,7 +463,7 @@ int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
orig_end = res.end;
while ((res.start < res.end) &&
- (find_next_system_ram(&res, "System RAM") >= 0)) {
+ (find_next_iomem_res(&res, "System RAM", true) >= 0)) {
pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT;
end_pfn = (res.end + 1) >> PAGE_SHIFT;
if (end_pfn > pfn)
@@ -411,6 +492,42 @@ int __weak page_is_ram(unsigned long pfn)
}
EXPORT_SYMBOL_GPL(page_is_ram);
+/*
+ * Search for a resouce entry that fully contains the specified region.
+ * If found, return 1 if it is RAM, 0 if not.
+ * If not found, or region is not fully contained, return -1
+ *
+ * Used by the ioremap functions to ensure the user is not remapping RAM and is
+ * a vast speed up over walking through the resource table page by page.
+ */
+int region_is_ram(resource_size_t start, unsigned long size)
+{
+ struct resource *p;
+ resource_size_t end = start + size - 1;
+ int flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+ const char *name = "System RAM";
+ int ret = -1;
+
+ read_lock(&resource_lock);
+ for (p = iomem_resource.child; p ; p = p->sibling) {
+ if (end < p->start)
+ continue;
+
+ if (p->start <= start && end <= p->end) {
+ /* resource fully contains region */
+ if ((p->flags != flags) || strcmp(p->name, name))
+ ret = 0;
+ else
+ ret = 1;
+ break;
+ }
+ if (p->end < start)
+ break; /* not found */
+ }
+ read_unlock(&resource_lock);
+ return ret;
+}
+
void __weak arch_remove_reservations(struct resource *avail)
{
}
@@ -1165,6 +1282,76 @@ int release_mem_region_adjustable(struct resource *parent,
/*
* Managed region resource
*/
+static void devm_resource_release(struct device *dev, void *ptr)
+{
+ struct resource **r = ptr;
+
+ release_resource(*r);
+}
+
+/**
+ * devm_request_resource() - request and reserve an I/O or memory resource
+ * @dev: device for which to request the resource
+ * @root: root of the resource tree from which to request the resource
+ * @new: descriptor of the resource to request
+ *
+ * This is a device-managed version of request_resource(). There is usually
+ * no need to release resources requested by this function explicitly since
+ * that will be taken care of when the device is unbound from its driver.
+ * If for some reason the resource needs to be released explicitly, because
+ * of ordering issues for example, drivers must call devm_release_resource()
+ * rather than the regular release_resource().
+ *
+ * When a conflict is detected between any existing resources and the newly
+ * requested resource, an error message will be printed.
+ *
+ * Returns 0 on success or a negative error code on failure.
+ */
+int devm_request_resource(struct device *dev, struct resource *root,
+ struct resource *new)
+{
+ struct resource *conflict, **ptr;
+
+ ptr = devres_alloc(devm_resource_release, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return -ENOMEM;
+
+ *ptr = new;
+
+ conflict = request_resource_conflict(root, new);
+ if (conflict) {
+ dev_err(dev, "resource collision: %pR conflicts with %s %pR\n",
+ new, conflict->name, conflict);
+ devres_free(ptr);
+ return -EBUSY;
+ }
+
+ devres_add(dev, ptr);
+ return 0;
+}
+EXPORT_SYMBOL(devm_request_resource);
+
+static int devm_resource_match(struct device *dev, void *res, void *data)
+{
+ struct resource **ptr = res;
+
+ return *ptr == data;
+}
+
+/**
+ * devm_release_resource() - release a previously requested resource
+ * @dev: device for which to release the resource
+ * @new: descriptor of the resource to release
+ *
+ * Releases a resource previously requested using devm_request_resource().
+ */
+void devm_release_resource(struct device *dev, struct resource *new)
+{
+ WARN_ON(devres_release(dev, devm_resource_release, devm_resource_match,
+ new));
+}
+EXPORT_SYMBOL(devm_release_resource);
+
struct region_devres {
struct resource *parent;
resource_size_t start;
@@ -1343,6 +1530,30 @@ int iomem_is_exclusive(u64 addr)
return err;
}
+struct resource_entry *resource_list_create_entry(struct resource *res,
+ size_t extra_size)
+{
+ struct resource_entry *entry;
+
+ entry = kzalloc(sizeof(*entry) + extra_size, GFP_KERNEL);
+ if (entry) {
+ INIT_LIST_HEAD(&entry->node);
+ entry->res = res ? res : &entry->__res;
+ }
+
+ return entry;
+}
+EXPORT_SYMBOL(resource_list_create_entry);
+
+void resource_list_free(struct list_head *head)
+{
+ struct resource_entry *entry, *tmp;
+
+ list_for_each_entry_safe(entry, tmp, head, node)
+ resource_list_destroy_entry(entry);
+}
+EXPORT_SYMBOL(resource_list_free);
+
static int __init strict_iomem(char *str)
{
if (strstr(str, "relaxed"))