ACPI: Clean up acpi_os_map/unmap_memory() to eliminate __iomem.
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.c
This 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 <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/acpi/acpi_extlog.c b/drivers/acpi/acpi_extlog.c
index c4a5d87..1853341 100644
--- a/drivers/acpi/acpi_extlog.c
+++ b/drivers/acpi/acpi_extlog.c
@@ -220,13 +220,13 @@
goto err;
}
- extlog_l1_hdr = acpi_os_map_memory(l1_dirbase, l1_hdr_size);
+ extlog_l1_hdr = acpi_os_map_iomem(l1_dirbase, l1_hdr_size);
l1_head = (struct extlog_l1_head *)extlog_l1_hdr;
l1_size = l1_head->total_len;
l1_percpu_entry = l1_head->entries;
elog_base = l1_head->elog_base;
elog_size = l1_head->elog_len;
- acpi_os_unmap_memory(extlog_l1_hdr, l1_hdr_size);
+ acpi_os_unmap_iomem(extlog_l1_hdr, l1_hdr_size);
release_mem_region(l1_dirbase, l1_hdr_size);
/* remap L1 header again based on completed information */
@@ -237,7 +237,7 @@
(unsigned long long)l1_dirbase + l1_size);
goto err;
}
- extlog_l1_addr = acpi_os_map_memory(l1_dirbase, l1_size);
+ extlog_l1_addr = acpi_os_map_iomem(l1_dirbase, l1_size);
l1_entry_base = (u64 *)((u8 *)extlog_l1_addr + l1_hdr_size);
/* remap elog table */
@@ -248,7 +248,7 @@
(unsigned long long)elog_base + elog_size);
goto err_release_l1_dir;
}
- elog_addr = acpi_os_map_memory(elog_base, elog_size);
+ elog_addr = acpi_os_map_iomem(elog_base, elog_size);
rc = -ENOMEM;
/* allocate buffer to save elog record */
@@ -270,11 +270,11 @@
err_release_elog:
if (elog_addr)
- acpi_os_unmap_memory(elog_addr, elog_size);
+ acpi_os_unmap_iomem(elog_addr, elog_size);
release_mem_region(elog_base, elog_size);
err_release_l1_dir:
if (extlog_l1_addr)
- acpi_os_unmap_memory(extlog_l1_addr, l1_size);
+ acpi_os_unmap_iomem(extlog_l1_addr, l1_size);
release_mem_region(l1_dirbase, l1_size);
err:
pr_warn(FW_BUG "Extended error log disabled because of problems parsing f/w tables\n");
@@ -287,9 +287,9 @@
mce_unregister_decode_chain(&extlog_mce_dec);
((struct extlog_l1_head *)extlog_l1_addr)->flags &= ~FLAG_OS_OPTIN;
if (extlog_l1_addr)
- acpi_os_unmap_memory(extlog_l1_addr, l1_size);
+ acpi_os_unmap_iomem(extlog_l1_addr, l1_size);
if (elog_addr)
- acpi_os_unmap_memory(elog_addr, elog_size);
+ acpi_os_unmap_iomem(elog_addr, elog_size);
release_mem_region(elog_base, elog_size);
release_mem_region(l1_dirbase, l1_size);
kfree(elog_buf);