[PATCH 1/2] ACPI / OSL: Cleanup initrd table override code

[Lv Zheng]

This patch cleans up initrd table override code, merging redundant logics
and re-ordering code blocks. No functional changes.

Signed-off-by: Lv Zheng 
---
 drivers/acpi/osl.c |  114 
 1 file changed, 52 insertions(+), 62 deletions(-)

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 67da6fb..a8c417c 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -602,6 +602,14 @@ acpi_os_predefined_override(const struct 
acpi_predefined_names *init_val,
return AE_OK;
 }
 
+static void acpi_table_taint(struct acpi_table_header *table)
+{
+   pr_warn(PREFIX
+   "Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
+   table->signature, table->oem_table_id);
+   add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
+}
+
 #ifdef CONFIG_ACPI_INITRD_TABLE_OVERRIDE
 #include 
 #include 
@@ -746,96 +754,78 @@ void __init acpi_initrd_override(void *data, size_t size)
}
}
 }
-#endif /* CONFIG_ACPI_INITRD_TABLE_OVERRIDE */
-
-static void acpi_table_taint(struct acpi_table_header *table)
-{
-   pr_warn(PREFIX
-   "Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
-   table->signature, table->oem_table_id);
-   add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
-}
-
-
-acpi_status
-acpi_os_table_override(struct acpi_table_header * existing_table,
-  struct acpi_table_header ** new_table)
-{
-   if (!existing_table || !new_table)
-   return AE_BAD_PARAMETER;
-
-   *new_table = NULL;
-
-#ifdef CONFIG_ACPI_CUSTOM_DSDT
-   if (strncmp(existing_table->signature, "DSDT", 4) == 0)
-   *new_table = (struct acpi_table_header *)AmlCode;
-#endif
-   if (*new_table != NULL)
-   acpi_table_taint(existing_table);
-   return AE_OK;
-}
 
 acpi_status
 acpi_os_physical_table_override(struct acpi_table_header *existing_table,
-   acpi_physical_address *address,
-   u32 *table_length)
+   acpi_physical_address *address, u32 *length)
 {
-#ifndef CONFIG_ACPI_INITRD_TABLE_OVERRIDE
-   *table_length = 0;
-   *address = 0;
-   return AE_OK;
-#else
int table_offset = 0;
struct acpi_table_header *table;
+   u32 table_length;
 
-   *table_length = 0;
+   *length = 0;
*address = 0;
-
if (!acpi_tables_addr)
return AE_OK;
 
-   do {
-   if (table_offset + ACPI_HEADER_SIZE > all_tables_size) {
-   WARN_ON(1);
-   return AE_OK;
-   }
-
+   while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
table = acpi_os_map_memory(acpi_tables_addr + table_offset,
   ACPI_HEADER_SIZE);
-
if (table_offset + table->length > all_tables_size) {
acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
WARN_ON(1);
return AE_OK;
}
 
-   table_offset += table->length;
+   table_length = table->length;
 
-   if (memcmp(existing_table->signature, table->signature, 4)) {
-   acpi_os_unmap_memory(table,
-ACPI_HEADER_SIZE);
-   continue;
-   }
-
-   /* Only override tables with matching oem id */
-   if (memcmp(table->oem_table_id, existing_table->oem_table_id,
+   /* Only override tables matched */
+   if (memcmp(existing_table->signature, table->signature, 4) ||
+   memcmp(table->oem_table_id, existing_table->oem_table_id,
   ACPI_OEM_TABLE_ID_SIZE)) {
-   acpi_os_unmap_memory(table,
-ACPI_HEADER_SIZE);
-   continue;
+   acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+   goto next_table;
}
 
-   table_offset -= table->length;
-   *table_length = table->length;
-   acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+   *length = table_length;
*address = acpi_tables_addr + table_offset;
+   acpi_table_taint(existing_table);
+   acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
break;
-   } while (table_offset + ACPI_HEADER_SIZE < all_tables_size);
 
-   if (*address != 0)
-   acpi_table_taint(existing_table);
+next_table:
+   table_offset += table_length;
+   }
return AE_OK;
+}
+#else
+acpi_status
+acpi_os_physical_table_override(struct acpi_table_header *existing_table,
+   acpi_physical_address *address,
+  

[PATCH 1/2] ACPI / OSL: Cleanup initrd table override code

[Lv Zheng]

This patch cleans up initrd table override code, merging redundant logics
and re-ordering code blocks. No functional changes.

Signed-off-by: Lv Zheng 
---
 drivers/acpi/osl.c |  114 
 1 file changed, 52 insertions(+), 62 deletions(-)

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 67da6fb..a8c417c 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -602,6 +602,14 @@ acpi_os_predefined_override(const struct 
acpi_predefined_names *init_val,
return AE_OK;
 }
 
+static void acpi_table_taint(struct acpi_table_header *table)
+{
+   pr_warn(PREFIX
+   "Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
+   table->signature, table->oem_table_id);
+   add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
+}
+
 #ifdef CONFIG_ACPI_INITRD_TABLE_OVERRIDE
 #include 
 #include 
@@ -746,96 +754,78 @@ void __init acpi_initrd_override(void *data, size_t size)
}
}
 }
-#endif /* CONFIG_ACPI_INITRD_TABLE_OVERRIDE */
-
-static void acpi_table_taint(struct acpi_table_header *table)
-{
-   pr_warn(PREFIX
-   "Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
-   table->signature, table->oem_table_id);
-   add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
-}
-
-
-acpi_status
-acpi_os_table_override(struct acpi_table_header * existing_table,
-  struct acpi_table_header ** new_table)
-{
-   if (!existing_table || !new_table)
-   return AE_BAD_PARAMETER;
-
-   *new_table = NULL;
-
-#ifdef CONFIG_ACPI_CUSTOM_DSDT
-   if (strncmp(existing_table->signature, "DSDT", 4) == 0)
-   *new_table = (struct acpi_table_header *)AmlCode;
-#endif
-   if (*new_table != NULL)
-   acpi_table_taint(existing_table);
-   return AE_OK;
-}
 
 acpi_status
 acpi_os_physical_table_override(struct acpi_table_header *existing_table,
-   acpi_physical_address *address,
-   u32 *table_length)
+   acpi_physical_address *address, u32 *length)
 {
-#ifndef CONFIG_ACPI_INITRD_TABLE_OVERRIDE
-   *table_length = 0;
-   *address = 0;
-   return AE_OK;
-#else
int table_offset = 0;
struct acpi_table_header *table;
+   u32 table_length;
 
-   *table_length = 0;
+   *length = 0;
*address = 0;
-
if (!acpi_tables_addr)
return AE_OK;
 
-   do {
-   if (table_offset + ACPI_HEADER_SIZE > all_tables_size) {
-   WARN_ON(1);
-   return AE_OK;
-   }
-
+   while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
table = acpi_os_map_memory(acpi_tables_addr + table_offset,
   ACPI_HEADER_SIZE);
-
if (table_offset + table->length > all_tables_size) {
acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
WARN_ON(1);
return AE_OK;
}
 
-   table_offset += table->length;
+   table_length = table->length;
 
-   if (memcmp(existing_table->signature, table->signature, 4)) {
-   acpi_os_unmap_memory(table,
-ACPI_HEADER_SIZE);
-   continue;
-   }
-
-   /* Only override tables with matching oem id */
-   if (memcmp(table->oem_table_id, existing_table->oem_table_id,
+   /* Only override tables matched */
+   if (memcmp(existing_table->signature, table->signature, 4) ||
+   memcmp(table->oem_table_id, existing_table->oem_table_id,
   ACPI_OEM_TABLE_ID_SIZE)) {
-   acpi_os_unmap_memory(table,
-ACPI_HEADER_SIZE);
-   continue;
+   acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+   goto next_table;
}
 
-   table_offset -= table->length;
-   *table_length = table->length;
-   acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+   *length = table_length;
*address = acpi_tables_addr + table_offset;
+   acpi_table_taint(existing_table);
+   acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
break;
-   } while (table_offset + ACPI_HEADER_SIZE < all_tables_size);
 
-   if (*address != 0)
-   acpi_table_taint(existing_table);
+next_table:
+   table_offset += table_length;
+   }
return AE_OK;
+}
+#else
+acpi_status
+acpi_os_physical_table_override(struct acpi_table_header *existing_table,
+   acpi_physical_address *address,
+