1 files changed, 173 insertions, 2 deletions

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index e53fb516f9d4..222f7b1b66f7 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -44,6 +44,8 @@
 #include <asm/uaccess.h>
 
 #include <linux/efi.h>
+#include <linux/ioport.h>
+#include <linux/list.h>
 
 #define _COMPONENT              ACPI_OS_SERVICES
 ACPI_MODULE_NAME("osl");
@@ -74,6 +76,18 @@ static void *acpi_irq_context;
 static struct workqueue_struct *kacpid_wq;
 static struct workqueue_struct *kacpi_notify_wq;
 
+struct acpi_res_list {
+        resource_size_t start;
+        resource_size_t end;
+        acpi_adr_space_type resource_type; /* IO port, System memory, ...*/
+        char name[5];   /* only can have a length of 4 chars, make use of this
+                           one instead of res->name, no need to kalloc then */
+        struct list_head resource_list;
+};
+
+static LIST_HEAD(resource_list_head);
+static DEFINE_SPINLOCK(acpi_res_lock);
+
 #define OSI_STRING_LENGTH_MAX 64        /* arbitrary */
 static char osi_additional_string[OSI_STRING_LENGTH_MAX];
 
@@ -1102,6 +1116,127 @@ static int __init acpi_wake_gpes_always_on_setup(char *str)
 
 __setup("acpi_wake_gpes_always_on", acpi_wake_gpes_always_on_setup);
 
+/* Check of resource interference between native drivers and ACPI
+ * OperationRegions (SystemIO and System Memory only).
+ * IO ports and memory declared in ACPI might be used by the ACPI subsystem
+ * in arbitrary AML code and can interfere with legacy drivers.
+ * acpi_enforce_resources= can be set to:
+ *
+ *   - strict           (2)
+ *     -> further driver trying to access the resources will not load
+ *   - lax (default)    (1)
+ *     -> further driver trying to access the resources will load, but you
+ *     get a system message that something might go wrong...
+ *
+ *   - no               (0)
+ *     -> ACPI Operation Region resources will not be registered
+ *
+ */
+#define ENFORCE_RESOURCES_STRICT 2
+#define ENFORCE_RESOURCES_LAX    1
+#define ENFORCE_RESOURCES_NO     0
+
+static unsigned int acpi_enforce_resources = ENFORCE_RESOURCES_LAX;
+
+static int __init acpi_enforce_resources_setup(char *str)
+{
+        if (str == NULL || *str == '\0')
+                return 0;
+
+        if (!strcmp("strict", str))
+                acpi_enforce_resources = ENFORCE_RESOURCES_STRICT;
+        else if (!strcmp("lax", str))
+                acpi_enforce_resources = ENFORCE_RESOURCES_LAX;
+        else if (!strcmp("no", str))
+                acpi_enforce_resources = ENFORCE_RESOURCES_NO;
+
+        return 1;
+}
+
+__setup("acpi_enforce_resources=", acpi_enforce_resources_setup);
+
+/* Check for resource conflicts between ACPI OperationRegions and native
+ * drivers */
+static int acpi_check_resource_conflict(struct resource *res)
+{
+        struct acpi_res_list *res_list_elem;
+        int ioport;
+        int clash = 0;
+
+        if (acpi_enforce_resources == ENFORCE_RESOURCES_NO)
+                return 0;
+        if (!(res->flags & IORESOURCE_IO) && !(res->flags & IORESOURCE_MEM))
+                return 0;
+
+        ioport = res->flags & IORESOURCE_IO;
+
+        spin_lock(&acpi_res_lock);
+        list_for_each_entry(res_list_elem, &resource_list_head,
+                            resource_list) {
+                if (ioport && (res_list_elem->resource_type
+                               != ACPI_ADR_SPACE_SYSTEM_IO))
+                        continue;
+                if (!ioport && (res_list_elem->resource_type
+                                != ACPI_ADR_SPACE_SYSTEM_MEMORY))
+                        continue;
+
+                if (res->end < res_list_elem->start
+                    || res_list_elem->end < res->start)
+                        continue;
+                clash = 1;
+                break;
+        }
+        spin_unlock(&acpi_res_lock);
+
+        if (clash) {
+                if (acpi_enforce_resources != ENFORCE_RESOURCES_NO) {
+                        printk(KERN_INFO "%sACPI: %s resource %s [0x%llx-0x%llx]"
+                               " conflicts with ACPI region %s"
+                               " [0x%llx-0x%llx]\n",
+                               acpi_enforce_resources == ENFORCE_RESOURCES_LAX
+                               ? KERN_WARNING : KERN_ERR,
+                               ioport ? "I/O" : "Memory", res->name,
+                               (long long) res->start, (long long) res->end,
+                               res_list_elem->name,
+                               (long long) res_list_elem->start,
+                               (long long) res_list_elem->end);
+                        printk(KERN_INFO "ACPI: Device needs an ACPI driver\n");
+                }
+                if (acpi_enforce_resources == ENFORCE_RESOURCES_STRICT)
+                        return -EBUSY;
+        }
+        return 0;
+}
+
+int acpi_check_region(resource_size_t start, resource_size_t n,
+                      const char *name)
+{
+        struct resource res = {
+                .start = start,
+                .end   = start + n - 1,
+                .name  = name,
+                .flags = IORESOURCE_IO,
+        };
+
+        return acpi_check_resource_conflict(&res);
+}
+EXPORT_SYMBOL(acpi_check_region);
+
+int acpi_check_mem_region(resource_size_t start, resource_size_t n,
+                      const char *name)
+{
+        struct resource res = {
+                .start = start,
+                .end   = start + n - 1,
+                .name  = name,
+                .flags = IORESOURCE_MEM,
+        };
+
+        return acpi_check_resource_conflict(&res);
+
+}
+EXPORT_SYMBOL(acpi_check_mem_region);
+
 /*
  * Acquire a spinlock.
  *
@@ -1303,10 +1438,46 @@ acpi_status
 acpi_os_validate_address (
     u8                   space_id,
     acpi_physical_address   address,
-    acpi_size               length)
+    acpi_size               length,
+    char *name)
 {
+        struct acpi_res_list *res;
+        if (acpi_enforce_resources == ENFORCE_RESOURCES_NO)
+                return AE_OK;
 
-    return AE_OK;
+        switch (space_id) {
+        case ACPI_ADR_SPACE_SYSTEM_IO:
+        case ACPI_ADR_SPACE_SYSTEM_MEMORY:
+                /* Only interference checks against SystemIO and SytemMemory
+                   are needed */
+                res = kzalloc(sizeof(struct acpi_res_list), GFP_KERNEL);
+                if (!res)
+                        return AE_OK;
+                /* ACPI names are fixed to 4 bytes, still better use strlcpy */
+                strlcpy(res->name, name, 5);
+                res->start = address;
+                res->end = address + length - 1;
+                res->resource_type = space_id;
+                spin_lock(&acpi_res_lock);
+                list_add(&res->resource_list, &resource_list_head);
+                spin_unlock(&acpi_res_lock);
+                pr_debug("Added %s resource: start: 0x%llx, end: 0x%llx, "
+                         "name: %s\n", (space_id == ACPI_ADR_SPACE_SYSTEM_IO)
+                         ? "SystemIO" : "System Memory",
+                         (unsigned long long)res->start,
+                         (unsigned long long)res->end,
+                         res->name);
+                break;
+        case ACPI_ADR_SPACE_PCI_CONFIG:
+        case ACPI_ADR_SPACE_EC:
+        case ACPI_ADR_SPACE_SMBUS:
+        case ACPI_ADR_SPACE_CMOS:
+        case ACPI_ADR_SPACE_PCI_BAR_TARGET:
+        case ACPI_ADR_SPACE_DATA_TABLE:
+        case ACPI_ADR_SPACE_FIXED_HARDWARE:
+                break;
+        }
+        return AE_OK;
 }
 
 #endif