On 20.03.2014 00:09, Ashwin Chaugule wrote:
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().
Signed-off-by: Ashwin Chaugule ashwin.chaugule@linaro.org
drivers/acpi/tables.c | 69 +++++++++++++++++++++++++++++++++++---------------- include/linux/acpi.h | 4 +++ 2 files changed, 51 insertions(+), 22 deletions(-)
diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c index 5837f85..b7bd6a3 100644 --- a/drivers/acpi/tables.c +++ b/drivers/acpi/tables.c @@ -199,19 +199,15 @@ 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(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; unsigned long table_end;
acpi_size tbl_size;
if (acpi_disabled) return -ENODEV;
@@ -219,16 +215,14 @@ acpi_table_parse_entries(char *id, if (!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_header) {
printk(KERN_WARNING PREFIX "%4.4s not present\n", id);
pr_warn(PREFIX "Table header not present\n");return -ENODEV; }
if (!table_size)
table_size = table_header->length;
If table_size == 0, that would causes 'entry' and 'table_end' are equal and no entries at all. For that case I would suggest to print error and return.
Tomasz
table_end = (unsigned long)table_header + table_header->length;
/* Parse all entries looking for a match. */ @@ -240,15 +234,18 @@ acpi_table_parse_entries(char *id, table_end) { if (entry->type == entry_id && (!max_entries || count++ < max_entries))
if (handler(entry, table_end))
if (handler(entry, table_end)) {count = -EINVAL; goto err;}/*
- If entry->length is 0, break from this loop to avoid
- infinite loop.
*/ if (entry->length == 0) {
pr_err(PREFIX "[%4.4s:0x%02x] Invalid zero length\n", id, entry_id);
pr_err(PREFIX "[0x%02x] Invalid zero length\n", entry_id);count = -EINVAL; goto err;@@ -256,15 +253,43 @@ acpi_table_parse_entries(char *id, ((unsigned long)entry + entry->length); } if (max_entries && count > max_entries) {
printk(KERN_WARNING PREFIX "[%4.4s:0x%02x] ignored %i entries of ""%i found\n", id, entry_id, count - max_entries, count);
printk(KERN_WARNING PREFIX "[0x%02x] ignored %i entries of ""%i found\n", entry_id, count - max_entries, count);
- early_acpi_os_unmap_memory((char *)table_header, tbl_size);
- return count; err:
- early_acpi_os_unmap_memory((char *)table_header, tbl_size);
- return -EINVAL;
- early_acpi_os_unmap_memory((char *)table_header, (acpi_size)table_size);
- return count;
Changelog is saying that acpi_parse_entries() takes already mapped table and parses entries. IMO, caller should takes care about unmapping table. It can be still parsed using different ID later on.
Tomasz
+}
+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;
if (acpi_disabled)
return -ENODEV;if (!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_header) {
pr_warn("%4.4s not present\n", id);return -ENODEV;}
return acpi_parse_entries(table_header->length, handler, table_header,
entry_id, max_entries);}
int __init
diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 1151a1d..da959fd 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -118,6 +118,10 @@ 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(unsigned long table_size,
acpi_tbl_entry_handler handler,struct acpi_table_header *table_header,int entry_id, unsigned int max_entries);