From a238317ce8185519ed083e81e84260907fbbcf7f Mon Sep 17 00:00:00 2001 From: Lv Zheng Date: Tue, 20 May 2014 15:39:41 +0800 Subject: 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 Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpi_extlog.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'drivers/acpi/acpi_extlog.c') diff --git a/drivers/acpi/acpi_extlog.c b/drivers/acpi/acpi_extlog.c index c4a5d87ede7e..185334114d71 100644 --- a/drivers/acpi/acpi_extlog.c +++ b/drivers/acpi/acpi_extlog.c @@ -220,13 +220,13 @@ static int __init extlog_init(void) 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 @@ static int __init extlog_init(void) (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 @@ static int __init extlog_init(void) (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 @@ static int __init extlog_init(void) 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 @@ static void __exit extlog_exit(void) 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); -- cgit v1.2.3