1 files changed, 232 insertions, 48 deletions

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index d3bed219c442..0c2e445410ab 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -95,6 +95,21 @@ struct acpi_res_list {
 static LIST_HEAD(resource_list_head);
 static DEFINE_SPINLOCK(acpi_res_lock);
 
+/*
+ * This list of permanent mappings is for memory that may be accessed from
+ * interrupt context, where we can't do the ioremap().
+ */
+struct acpi_ioremap {
+        struct list_head list;
+        void __iomem *virt;
+        acpi_physical_address phys;
+        acpi_size size;
+        struct kref ref;
+};
+
+static LIST_HEAD(acpi_ioremaps);
+static DEFINE_SPINLOCK(acpi_ioremap_lock);
+
 #define OSI_STRING_LENGTH_MAX 64        /* arbitrary */
 static char osi_setup_string[OSI_STRING_LENGTH_MAX];
 
@@ -201,38 +216,6 @@ static int __init acpi_reserve_resources(void)
 }
 device_initcall(acpi_reserve_resources);
 
-acpi_status __init acpi_os_initialize(void)
-{
-        return AE_OK;
-}
-
-acpi_status acpi_os_initialize1(void)
-{
-        kacpid_wq = create_workqueue("kacpid");
-        kacpi_notify_wq = create_workqueue("kacpi_notify");
-        kacpi_hotplug_wq = create_workqueue("kacpi_hotplug");
-        BUG_ON(!kacpid_wq);
-        BUG_ON(!kacpi_notify_wq);
-        BUG_ON(!kacpi_hotplug_wq);
-        acpi_install_interface_handler(acpi_osi_handler);
-        acpi_osi_setup_late();
-        return AE_OK;
-}
-
-acpi_status acpi_os_terminate(void)
-{
-        if (acpi_irq_handler) {
-                acpi_os_remove_interrupt_handler(acpi_irq_irq,
-                                                 acpi_irq_handler);
-        }
-
-        destroy_workqueue(kacpid_wq);
-        destroy_workqueue(kacpi_notify_wq);
-        destroy_workqueue(kacpi_hotplug_wq);
-
-        return AE_OK;
-}
-
 void acpi_os_printf(const char *fmt, ...)
 {
         va_list args;
@@ -278,29 +261,135 @@ acpi_physical_address __init acpi_os_get_root_pointer(void)
         }
 }
 
+/* Must be called with 'acpi_ioremap_lock' or RCU read lock held. */
+static struct acpi_ioremap *
+acpi_map_lookup(acpi_physical_address phys, acpi_size size)
+{
+        struct acpi_ioremap *map;
+
+        list_for_each_entry_rcu(map, &acpi_ioremaps, list)
+                if (map->phys <= phys &&
+                    phys + size <= map->phys + map->size)
+                        return map;
+
+        return NULL;
+}
+
+/* Must be called with 'acpi_ioremap_lock' or RCU read lock held. */
+static void __iomem *
+acpi_map_vaddr_lookup(acpi_physical_address phys, unsigned int size)
+{
+        struct acpi_ioremap *map;
+
+        map = acpi_map_lookup(phys, size);
+        if (map)
+                return map->virt + (phys - map->phys);
+
+        return NULL;
+}
+
+/* Must be called with 'acpi_ioremap_lock' or RCU read lock held. */
+static struct acpi_ioremap *
+acpi_map_lookup_virt(void __iomem *virt, acpi_size size)
+{
+        struct acpi_ioremap *map;
+
+        list_for_each_entry_rcu(map, &acpi_ioremaps, list)
+                if (map->virt <= virt &&
+                    virt + size <= map->virt + map->size)
+                        return map;
+
+        return NULL;
+}
+
 void __iomem *__init_refok
 acpi_os_map_memory(acpi_physical_address phys, acpi_size size)
 {
+        struct acpi_ioremap *map, *tmp_map;
+        unsigned long flags, pg_sz;
+        void __iomem *virt;
+        phys_addr_t pg_off;
+
         if (phys > ULONG_MAX) {
                 printk(KERN_ERR PREFIX "Cannot map memory that high\n");
                 return NULL;
         }
-        if (acpi_gbl_permanent_mmap)
-                /*
-                * ioremap checks to ensure this is in reserved space
-                */
-                return ioremap((unsigned long)phys, size);
-        else
+
+        if (!acpi_gbl_permanent_mmap)
                 return __acpi_map_table((unsigned long)phys, size);
+
+        map = kzalloc(sizeof(*map), GFP_KERNEL);
+        if (!map)
+                return NULL;
+
+        pg_off = round_down(phys, PAGE_SIZE);
+        pg_sz = round_up(phys + size, PAGE_SIZE) - pg_off;
+        virt = ioremap(pg_off, pg_sz);
+        if (!virt) {
+                kfree(map);
+                return NULL;
+        }
+
+        INIT_LIST_HEAD(&map->list);
+        map->virt = virt;
+        map->phys = pg_off;
+        map->size = pg_sz;
+        kref_init(&map->ref);
+
+        spin_lock_irqsave(&acpi_ioremap_lock, flags);
+        /* Check if page has already been mapped. */
+        tmp_map = acpi_map_lookup(phys, size);
+        if (tmp_map) {
+                kref_get(&tmp_map->ref);
+                spin_unlock_irqrestore(&acpi_ioremap_lock, flags);
+                iounmap(map->virt);
+                kfree(map);
+                return tmp_map->virt + (phys - tmp_map->phys);
+        }
+        list_add_tail_rcu(&map->list, &acpi_ioremaps);
+        spin_unlock_irqrestore(&acpi_ioremap_lock, flags);
+
+        return map->virt + (phys - map->phys);
 }
 EXPORT_SYMBOL_GPL(acpi_os_map_memory);
 
+static void acpi_kref_del_iomap(struct kref *ref)
+{
+        struct acpi_ioremap *map;
+
+        map = container_of(ref, struct acpi_ioremap, ref);
+        list_del_rcu(&map->list);
+}
+
 void __ref acpi_os_unmap_memory(void __iomem *virt, acpi_size size)
 {
-        if (acpi_gbl_permanent_mmap)
-                iounmap(virt);
-        else
+        struct acpi_ioremap *map;
+        unsigned long flags;
+        int del;
+
+        if (!acpi_gbl_permanent_mmap) {
                 __acpi_unmap_table(virt, size);
+                return;
+        }
+
+        spin_lock_irqsave(&acpi_ioremap_lock, flags);
+        map = acpi_map_lookup_virt(virt, size);
+        if (!map) {
+                spin_unlock_irqrestore(&acpi_ioremap_lock, flags);
+                printk(KERN_ERR PREFIX "%s: bad address %p\n", __func__, virt);
+                dump_stack();
+                return;
+        }
+
+        del = kref_put(&map->ref, acpi_kref_del_iomap);
+        spin_unlock_irqrestore(&acpi_ioremap_lock, flags);
+
+        if (!del)
+                return;
+
+        synchronize_rcu();
+        iounmap(map->virt);
+        kfree(map);
 }
 EXPORT_SYMBOL_GPL(acpi_os_unmap_memory);
 
@@ -310,6 +399,44 @@ void __init early_acpi_os_unmap_memory(void __iomem *virt, acpi_size size)
                 __acpi_unmap_table(virt, size);
 }
 
+int acpi_os_map_generic_address(struct acpi_generic_address *addr)
+{
+        void __iomem *virt;
+
+        if (addr->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY)
+                return 0;
+
+        if (!addr->address || !addr->bit_width)
+                return -EINVAL;
+
+        virt = acpi_os_map_memory(addr->address, addr->bit_width / 8);
+        if (!virt)
+                return -EIO;
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(acpi_os_map_generic_address);
+
+void acpi_os_unmap_generic_address(struct acpi_generic_address *addr)
+{
+        void __iomem *virt;
+        unsigned long flags;
+        acpi_size size = addr->bit_width / 8;
+
+        if (addr->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY)
+                return;
+
+        if (!addr->address || !addr->bit_width)
+                return;
+
+        spin_lock_irqsave(&acpi_ioremap_lock, flags);
+        virt = acpi_map_vaddr_lookup(addr->address, size);
+        spin_unlock_irqrestore(&acpi_ioremap_lock, flags);
+
+        acpi_os_unmap_memory(virt, size);
+}
+EXPORT_SYMBOL_GPL(acpi_os_unmap_generic_address);
+
 #ifdef ACPI_FUTURE_USAGE
 acpi_status
 acpi_os_get_physical_address(void *virt, acpi_physical_address * phys)
@@ -513,8 +640,15 @@ acpi_os_read_memory(acpi_physical_address phys_addr, u32 * value, u32 width)
 {
         u32 dummy;
         void __iomem *virt_addr;
-
-        virt_addr = ioremap(phys_addr, width);
+        int size = width / 8, unmap = 0;
+
+        rcu_read_lock();
+        virt_addr = acpi_map_vaddr_lookup(phys_addr, size);
+        rcu_read_unlock();
+        if (!virt_addr) {
+                virt_addr = ioremap(phys_addr, size);
+                unmap = 1;
+        }
         if (!value)
                 value = &dummy;
 
@@ -532,7 +666,8 @@ acpi_os_read_memory(acpi_physical_address phys_addr, u32 * value, u32 width)
                 BUG();
         }
 
-        iounmap(virt_addr);
+        if (unmap)
+                iounmap(virt_addr);
 
         return AE_OK;
 }
@@ -541,8 +676,15 @@ acpi_status
 acpi_os_write_memory(acpi_physical_address phys_addr, u32 value, u32 width)
 {
         void __iomem *virt_addr;
-
-        virt_addr = ioremap(phys_addr, width);
+        int size = width / 8, unmap = 0;
+
+        rcu_read_lock();
+        virt_addr = acpi_map_vaddr_lookup(phys_addr, size);
+        rcu_read_unlock();
+        if (!virt_addr) {
+                virt_addr = ioremap(phys_addr, size);
+                unmap = 1;
+        }
 
         switch (width) {
         case 8:
@@ -558,7 +700,8 @@ acpi_os_write_memory(acpi_physical_address phys_addr, u32 value, u32 width)
                 BUG();
         }
 
-        iounmap(virt_addr);
+        if (unmap)
+                iounmap(virt_addr);
 
         return AE_OK;
 }
@@ -1400,5 +1543,46 @@ acpi_os_validate_address (
         }
         return AE_OK;
 }
-
 #endif
+
+acpi_status __init acpi_os_initialize(void)
+{
+        acpi_os_map_generic_address(&acpi_gbl_FADT.xpm1a_event_block);
+        acpi_os_map_generic_address(&acpi_gbl_FADT.xpm1b_event_block);
+        acpi_os_map_generic_address(&acpi_gbl_FADT.xgpe0_block);
+        acpi_os_map_generic_address(&acpi_gbl_FADT.xgpe1_block);
+
+        return AE_OK;
+}
+
+acpi_status acpi_os_initialize1(void)
+{
+        kacpid_wq = create_workqueue("kacpid");
+        kacpi_notify_wq = create_workqueue("kacpi_notify");
+        kacpi_hotplug_wq = create_workqueue("kacpi_hotplug");
+        BUG_ON(!kacpid_wq);
+        BUG_ON(!kacpi_notify_wq);
+        BUG_ON(!kacpi_hotplug_wq);
+        acpi_install_interface_handler(acpi_osi_handler);
+        acpi_osi_setup_late();
+        return AE_OK;
+}
+
+acpi_status acpi_os_terminate(void)
+{
+        if (acpi_irq_handler) {
+                acpi_os_remove_interrupt_handler(acpi_irq_irq,
+                                                 acpi_irq_handler);
+        }
+
+        acpi_os_unmap_generic_address(&acpi_gbl_FADT.xgpe1_block);
+        acpi_os_unmap_generic_address(&acpi_gbl_FADT.xgpe0_block);
+        acpi_os_unmap_generic_address(&acpi_gbl_FADT.xpm1b_event_block);
+        acpi_os_unmap_generic_address(&acpi_gbl_FADT.xpm1a_event_block);
+
+        destroy_workqueue(kacpid_wq);
+        destroy_workqueue(kacpi_notify_wq);
+        destroy_workqueue(kacpi_hotplug_wq);
+
+        return AE_OK;
+}