[PATCH v2 2/9] ACPI: Change __init to __ref for early_acpi_os_unmap_memory()

From: Aleksey Makarov
Date: Fri Feb 12 2016 - 12:51:37 EST


early_acpi_os_unmap_memory() is marked as __init because it calls
__acpi_unmap_table(), but only when acpi_gbl_permanent_mmap is not set.

acpi_gbl_permanent_mmap is set in __init acpi_early_init()
so it is safe to call early_acpi_os_unmap_memory() from anywhere

We need this function to be non-__init because we need access to
some tables at unpredictable time--it may be before or after
acpi_gbl_permanent_mmap is set. For example, SPCR (Serial Port Console
Redirection) table is needed each time a new console is registered.
It can be quite early (console_initcall) or when a module is inserted.
When this table accessed before acpi_gbl_permanent_mmap is set,
the pointer should be unmapped. This is exactly what this function
does.

Signed-off-by: Aleksey Makarov <aleksey.makarov@xxxxxxxxxx>
---
drivers/acpi/osl.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 67da6fb..8a552cd 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -497,7 +497,11 @@ void __ref acpi_os_unmap_memory(void *virt, acpi_size size)
}
EXPORT_SYMBOL_GPL(acpi_os_unmap_memory);

-void __init early_acpi_os_unmap_memory(void __iomem *virt, acpi_size size)
+/*
+ * acpi_gbl_permanent_mmap is set in __init acpi_early_init()
+ * so it is safe to call early_acpi_os_unmap_memory() from anywhere
+ */
+void __ref early_acpi_os_unmap_memory(void __iomem *virt, acpi_size size)
{
if (!acpi_gbl_permanent_mmap)
__acpi_unmap_table(virt, size);
--
2.7.0