Commit 7bbb8903 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

ACPI: Change acpi_ioremap_lock into a mutex 



There's no reason why acpi_ioremap_lock has to be a spinlock,
because all of the functions it is used in may sleep anyway and
there's no reason why it should be locked with interrupts off.
Use a mutex instead (that's going to allow us to put some more
operations under the lock later).

Signed-off-by: default avatarRafael J. Wysocki <rjw@sisk.pl>
parent 073b4964

drivers/acpi/osl.c

+9 −12
Original line number Diff line number Diff line
@@ -109,7 +109,7 @@ struct acpi_ioremap { 
};



static LIST_HEAD(acpi_ioremaps);

static DEFINE_SPINLOCK(acpi_ioremap_lock);

static DEFINE_MUTEX(acpi_ioremap_lock);



static void __init acpi_osi_setup_late(void);
@@ -303,7 +303,6 @@ void __iomem *__init_refok 
acpi_os_map_memory(acpi_physical_address phys, acpi_size size)

{

	struct acpi_ioremap *map, *tmp_map;

	unsigned long flags;

	void __iomem *virt;

	acpi_physical_address pg_off;

	acpi_size pg_sz;
@@ -334,18 +333,18 @@ acpi_os_map_memory(acpi_physical_address phys, acpi_size size) 
	map->size = pg_sz;

	kref_init(&map->ref);



	spin_lock_irqsave(&acpi_ioremap_lock, flags);

	mutex_lock(&acpi_ioremap_lock);

	/* 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);

		mutex_unlock(&acpi_ioremap_lock);

		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);

	mutex_unlock(&acpi_ioremap_lock);



	return map->virt + (phys - map->phys);

}
@@ -362,7 +361,6 @@ static void acpi_kref_del_iomap(struct kref *ref) 
void __ref acpi_os_unmap_memory(void __iomem *virt, acpi_size size)

{

	struct acpi_ioremap *map;

	unsigned long flags;

	int del;



	if (!acpi_gbl_permanent_mmap) {
@@ -370,17 +368,17 @@ void __ref acpi_os_unmap_memory(void __iomem *virt, acpi_size size) 
		return;

	}



	spin_lock_irqsave(&acpi_ioremap_lock, flags);

	mutex_lock(&acpi_ioremap_lock);

	map = acpi_map_lookup_virt(virt, size);

	if (!map) {

		spin_unlock_irqrestore(&acpi_ioremap_lock, flags);

		mutex_unlock(&acpi_ioremap_lock);

		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);

	mutex_unlock(&acpi_ioremap_lock);



	if (!del)

		return;
@@ -417,7 +415,6 @@ static int acpi_os_map_generic_address(struct acpi_generic_address *addr) 
static 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)
@@ -426,9 +423,9 @@ static void acpi_os_unmap_generic_address(struct acpi_generic_address *addr) 
	if (!addr->address || !addr->bit_width)

		return;



	spin_lock_irqsave(&acpi_ioremap_lock, flags);

	mutex_lock(&acpi_ioremap_lock);

	virt = acpi_map_vaddr_lookup(addr->address, size);

	spin_unlock_irqrestore(&acpi_ioremap_lock, flags);

	mutex_unlock(&acpi_ioremap_lock);



	acpi_os_unmap_memory(virt, size);

}

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