ACPI / table: Add new function to get table entries

The acpi_table_parse() function has a callback that
passes a pointer to a table_header. Add a new function
which takes this pointer and parses its entries. This
eliminates the need to re-traverse all the tables for
each call. e.g. as in acpi_table_parse_madt() which is
normally called after acpi_table_parse().

Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: Tomasz Nowicki <tomasz.nowicki@linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c
index 6d5a6cda0734de6a46a577a71225dd43163acc69..f1debe97dcfcc1360a6fbc06e2336e8061d908fe 100644 (file)
--- a/drivers/acpi/tables.c
+++ b/drivers/acpi/tables.c
@@ -190,30 +190,24 @@ void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
        }
 }
 
-
 int __init
-acpi_table_parse_entries(char *id,
-                            unsigned long table_size,
-                            int entry_id,
-                            acpi_tbl_entry_handler handler,
-                            unsigned int max_entries)
+acpi_parse_entries(char *id, unsigned long table_size,
+               acpi_tbl_entry_handler handler,
+               struct acpi_table_header *table_header,
+               int entry_id, unsigned int max_entries)
 {
-       struct acpi_table_header *table_header = NULL;
        struct acpi_subtable_header *entry;
-       unsigned int count = 0;
+       int count = 0;
        unsigned long table_end;
-       acpi_size tbl_size;
 
        if (acpi_disabled)
                return -ENODEV;
 
-       if (!handler)
+       if (!id || !handler)
                return -EINVAL;
 
-       if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
-               acpi_get_table_with_size(id, acpi_apic_instance, &table_header, &tbl_size);
-       else
-               acpi_get_table_with_size(id, 0, &table_header, &tbl_size);
+       if (!table_size)
+               return -EINVAL;
 
        if (!table_header) {
                pr_warn("%4.4s not present\n", id);
@@ -232,7 +226,7 @@ acpi_table_parse_entries(char *id,
                if (entry->type == entry_id
                    && (!max_entries || count++ < max_entries))
                        if (handler(entry, table_end))
-                               goto err;
+                               return -EINVAL;
 
                /*
                 * If entry->length is 0, break from this loop to avoid
@@ -240,22 +234,53 @@ acpi_table_parse_entries(char *id,
                 */
                if (entry->length == 0) {
                        pr_err("[%4.4s:0x%02x] Invalid zero length\n", id, entry_id);
-                       goto err;
+                       return -EINVAL;
                }
 
                entry = (struct acpi_subtable_header *)
                    ((unsigned long)entry + entry->length);
        }
+
        if (max_entries && count > max_entries) {
                pr_warn("[%4.4s:0x%02x] ignored %i entries of %i found\n",
                        id, entry_id, count - max_entries, count);
        }
 
-       early_acpi_os_unmap_memory((char *)table_header, tbl_size);
        return count;
-err:
+}
+
+int __init
+acpi_table_parse_entries(char *id,
+                        unsigned long table_size,
+                        int entry_id,
+                        acpi_tbl_entry_handler handler,
+                        unsigned int max_entries)
+{
+       struct acpi_table_header *table_header = NULL;
+       acpi_size tbl_size;
+       int count;
+       u32 instance = 0;
+
+       if (acpi_disabled)
+               return -ENODEV;
+
+       if (!id || !handler)
+               return -EINVAL;
+
+       if (!strncmp(id, ACPI_SIG_MADT, 4))
+               instance = acpi_apic_instance;
+
+       acpi_get_table_with_size(id, instance, &table_header, &tbl_size);
+       if (!table_header) {
+               pr_warn("%4.4s not present\n", id);
+               return -ENODEV;
+       }
+
+       count = acpi_parse_entries(id, table_size, handler, table_header,
+                       entry_id, max_entries);
+
        early_acpi_os_unmap_memory((char *)table_header, tbl_size);
-       return -EINVAL;
+       return count;
 }
 
 int __init

diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 407a12f663ebdd313c166dcc4f5c892da1453ecf..3bd0c59e1fb90bd26cbde3adf114b85fe1286366 100644 (file)
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -123,6 +123,10 @@ int acpi_numa_init (void);
 
 int acpi_table_init (void);
 int acpi_table_parse(char *id, acpi_tbl_table_handler handler);
+int __init acpi_parse_entries(char *id, unsigned long table_size,
+                             acpi_tbl_entry_handler handler,
+                             struct acpi_table_header *table_header,
+                             int entry_id, unsigned int max_entries);
 int __init acpi_table_parse_entries(char *id, unsigned long table_size,
                                    int entry_id,
                                    acpi_tbl_entry_handler handler,