28 May, 2014
2 commits
-
ACPICA doesn't include protections around address space checking, Linux
build tests always complain increased sparse warnings around ACPICA
internal acpi_os_map/unmap_memory() invocations. This patch tries to fix
this issue permanently.There are 2 choices left for us to solve this issue:
1. Add __iomem address space awareness into ACPICA.
2. Remove sparse checker of __iomem from ACPICA source code.This patch chooses solution 2, because:
1. Most of the acpi_os_map/unmap_memory() invocations are used for ACPICA.
table mappings, which in fact are not IO addresses.
2. The only IO addresses usage is for "system memory space" mapping code in:
drivers/acpi/acpica/exregion.c
drivers/acpi/acpica/evrgnini.c
drivers/acpi/acpica/exregion.c
The mapped address is accessed in the handler of "system memory space"
- acpi_ex_system_memory_space_handler(). This function in fact can be
changed to invoke acpi_os_read/write_memory() so that __iomem can
always be type-casted in the OSL layer.According to the above investigation, we drew the following conclusion:
It is not a good idea to introduce __iomem address space awareness into
ACPICA mostly in order to protect non-IO addresses.We can simply remove __iomem for acpi_os_map/unmap_memory() to remove
__iomem checker for ACPICA code. Then we need to enforce external usages
to invoke other APIs that are aware of __iomem address space.
The external usages are:
drivers/acpi/apei/einj.c
drivers/acpi/acpi_extlog.c
drivers/char/tpm/tpm_acpi.c
drivers/acpi/nvs.cThis patch thus performs cleanups in this way:
1. Add acpi_os_map/unmap_iomem() to be invoked by non-ACPICA code.
2. Remove __iomem from acpi_os_map/unmap_memory().Signed-off-by: Lv Zheng
Signed-off-by: Rafael J. Wysocki -
From ACPICA's perspective, should be included after
inclusion of . But currently in Linux,
included by has
included to find ACPICA types for inline functions.This causes the following problem:
1. Redundant code in and :
Linux must be careful to keep conditions for inclusion
consistent with the conditions for inclusion.
Which finally leads to the issue that we have to keep many useless macro
definitions in or .
Such conditions include:
COMPILER_DEPENDENT_UINT64
COMPILER_DEPENDENT_INT64
ACPI_INLINE
ACPI_SYSTEM_XFACE
ACPI_EXTERNAL_XFACE
ACPI_INTERNAL_XFACE
ACPI_INTERNAL_VAR_XFACE
ACPI_MUTEX_TYPE
DEBUGGER_THREADING
ACPI_ACQUIRE_GLOBAL_LOCK
ACPI_RELEASE_GLOBAL_LOCK
ACPI_FLUSH_CPU_CACHE
They have default implementations in
while Linux need to keep a copy in to avoid build errors.This patch introduces to fix this issue by
splitting conditions and declarations (most of them are inline functions)
into 2 header files so that the wrong inclusion of can be
removed from .This patch also removes old ACPI_NATIVE_INTERFACE_HEADER mechanism which is
not preferred by Linux and adds the platform/acenvex.h to be the solution
to solve this issue.Signed-off-by: Lv Zheng
Signed-off-by: Rafael J. Wysocki
