===================================================================
@@ -175,11 +175,7 @@ static void __init acpi_request_region (
if (!addr || !length)
return;
- /* Resources are never freed */
- if (gas->space_id == ACPI_ADR_SPACE_SYSTEM_IO)
- request_region(addr, length, desc);
- else if (gas->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY)
- request_mem_region(addr, length, desc);
+ acpi_reserve_region(addr, length, gas->space_id, 0, desc);
}
static void __init acpi_reserve_resources(void)
===================================================================
@@ -26,6 +26,7 @@
#include <linux/device.h>
#include <linux/export.h>
#include <linux/ioport.h>
+#include <linux/list.h>
#include <linux/slab.h>
#ifdef CONFIG_X86
@@ -621,3 +622,131 @@ int acpi_dev_filter_resource_type(struct
return (type & types) ? 0 : 1;
}
EXPORT_SYMBOL_GPL(acpi_dev_filter_resource_type);
+
+struct acpi_region {
+ struct list_head node;
+ u64 start;
+ u64 end;
+};
+
+static LIST_HEAD(acpi_io_regions);
+static LIST_HEAD(acpi_mem_regions);
+
+static int acpi_add_region(u64 start, u64 end, struct list_head *head,
+ u8 space_id, unsigned long flags, char *desc)
+{
+ struct acpi_region *reg;
+ struct resource *res;
+ unsigned int length = end - start + 1;
+
+ reg = kmalloc(sizeof(*reg), GFP_KERNEL);
+ if (!reg)
+ return -ENOMEM;
+
+ reg->start = start;
+ reg->end = end;
+ list_add(®->node, head);
+ res = space_id == ACPI_ADR_SPACE_SYSTEM_IO ?
+ request_region(start, length, desc) :
+ request_mem_region(start, length, desc);
+ if (res) {
+ res->flags &= ~flags;
+ return 0;
+ }
+ return -EIO;
+}
+
+/**
+ * acpi_reserve_region - Reserve an I/O or memory region as a system resource.
+ * @start: Starting address of the region.
+ * @length: Length of the region.
+ * @space_id: Identifier of address space to reserve the region from.
+ * @flags: Resource flags to clear for the region after requesting it.
+ * @desc: Region description (for messages).
+ *
+ * Reserve an I/O or memory region as a system resource to prevent others from
+ * using it. If the new region overlaps with one of the regions (in the given
+ * address space) already reserved by this routine, only the non-overlapping
+ * parts of it will be reserved.
+ *
+ * Returned is either 0 (success) or a negative error code indicating a resource
+ * reservation problem. It is the code of the first encountered error, but the
+ * routine doesn't abort until it has attempted to request all of the parts of
+ * the new region that don't overlap with other regions reserved previously.
+ *
+ * The resources requested by this routine are never released.
+ */
+int acpi_reserve_region(u64 start, unsigned int length, u8 space_id,
+ unsigned long flags, char *desc)
+{
+ struct list_head *regions, *head;
+ struct acpi_region *reg;
+ u64 end = start + length - 1;
+ int ret = 0;
+
+ if (space_id == ACPI_ADR_SPACE_SYSTEM_IO)
+ regions = &acpi_io_regions;
+ else if (space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY)
+ regions = &acpi_mem_regions;
+ else
+ return -EINVAL;
+
+ if (list_empty(regions))
+ return acpi_add_region(start, end, regions, space_id, flags, desc);
+
+ reg = list_first_entry(regions, struct acpi_region, node);
+ if (reg->start > end) {
+ /* The new region goes in front of the first existing one. */
+ return acpi_add_region(start, end, regions, space_id, flags, desc);
+ } else if (reg->end >= start) {
+ head = reg->node.prev;
+ goto overlap;
+ }
+
+ loop:
+ head = NULL;
+ list_for_each_entry_continue(reg, regions, node)
+ if (reg->end < start) {
+ continue;
+ } else if (reg->start > end) {
+ /* No overlap, the new region can be inserted here. */
+ int auxret = acpi_add_region(start, end, reg->node.prev,
+ space_id, flags, desc);
+ return ret ? ret : auxret;
+ } else {
+ head = reg->node.prev;
+ break;
+ }
+
+ if (!head) {
+ /* The new region goes after the last existing one. */
+ int auxret = acpi_add_region(start, end, regions->prev,
+ space_id, flags, desc);
+ return ret ? ret : auxret;
+ }
+
+ overlap:
+ /*
+ * We know that reg->end >= start and reg->start <= end at this point.
+ * The part of the new region immediately preceding the existing
+ * overlapping one can be added right away.
+ */
+ if (reg->start > start) {
+ int auxret = acpi_add_region(start, reg->start - 1, head,
+ space_id, flags, desc);
+ if (!ret)
+ ret = auxret;
+ }
+
+ /*
+ * Skip the overlapping part of the new region and handle the rest as
+ * a new region to insert.
+ */
+ if (reg->end < end) {
+ start = reg->end + 1;
+ goto loop;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(acpi_reserve_region);
===================================================================
@@ -342,6 +342,9 @@ int acpi_check_region(resource_size_t st
int acpi_resources_are_enforced(void);
+int acpi_reserve_region(u64 start, unsigned int length, u8 space_id,
+ unsigned long flags, char *desc);
+
#ifdef CONFIG_HIBERNATION
void __init acpi_no_s4_hw_signature(void);
#endif
@@ -537,6 +540,13 @@ static inline int acpi_check_region(reso
return 0;
}
+static inline int acpi_reserve_region(u64 start, unsigned int length,
+ u8 space_id, unsigned long flags,
+ char *desc)
+{
+ return -ENXIO;
+}
+
struct acpi_table_header;
static inline int acpi_table_parse(char *id,
int (*handler)(struct acpi_table_header *))
===================================================================
@@ -7,6 +7,7 @@
* Bjorn Helgaas <bjorn.helgaas@hp.com>
*/
+#include <linux/acpi.h>
#include <linux/pnp.h>
#include <linux/device.h>
#include <linux/init.h>
@@ -22,25 +23,57 @@ static const struct pnp_device_id pnp_de
{"", 0}
};
+#ifdef CONFIG_ACPI
+static inline bool reserve_region(u64 start, unsigned int length, char *desc)
+{
+ return !acpi_reserve_region(start, length, ACPI_ADR_SPACE_SYSTEM_IO,
+ IORESOURCE_BUSY, desc);
+}
+static inline bool reserve_mem_region(u64 start, unsigned int length, char *desc)
+{
+ return !acpi_reserve_region(start, length, ACPI_ADR_SPACE_SYSTEM_MEMORY,
+ IORESOURCE_BUSY, desc);
+}
+#else
+static inline bool reserve_region(u64 start, unsigned int length, char *desc)
+{
+ struct resource *res;
+
+ res = request_region(start, length, desc);
+ if (res) {
+ res->flags &= ~IORESOURCE_BUSY;
+ return true;
+ }
+ return false;
+}
+static inline bool reserve_mem_region(u64 start, unsigned int length, char *desc)
+{
+ struct resource *res;
+
+ res = request_mem_region(start, length, desc);
+ if (res) {
+ res->flags &= ~IORESOURCE_BUSY;
+ return true;
+ }
+ return false;
+}
+#endif
+
static void reserve_range(struct pnp_dev *dev, struct resource *r, int port)
{
char *regionid;
const char *pnpid = dev_name(&dev->dev);
resource_size_t start = r->start, end = r->end;
- struct resource *res;
+ bool reserved;
regionid = kmalloc(16, GFP_KERNEL);
if (!regionid)
return;
snprintf(regionid, 16, "pnp %s", pnpid);
- if (port)
- res = request_region(start, end - start + 1, regionid);
- else
- res = request_mem_region(start, end - start + 1, regionid);
- if (res)
- res->flags &= ~IORESOURCE_BUSY;
- else
+ reserved = port ? reserve_region(start, end - start + 1, regionid) :
+ reserve_mem_region(start, end - start + 1, regionid);
+ if (!reserved)
kfree(regionid);
/*
@@ -49,7 +82,7 @@ static void reserve_range(struct pnp_dev
* have double reservations.
*/
dev_info(&dev->dev, "%pR %s reserved\n", r,
- res ? "has been" : "could not be");
+ reserved ? "has been" : "could not be");
}
static void reserve_resources_of_dev(struct pnp_dev *dev)