From f08bb472bff3c0397fb7d6f47bc5cec41dad76e3 Mon Sep 17 00:00:00 2001 From: Ashwin Chaugule Date: Wed, 26 Nov 2014 22:01:13 +0800 Subject: [PATCH] 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 Signed-off-by: Ashwin Chaugule Signed-off-by: Tomasz Nowicki Signed-off-by: Hanjun Guo Signed-off-by: Rafael J. Wysocki --- drivers/acpi/tables.c | 63 ++++++++++++++++++++++++++++++------------- include/linux/acpi.h | 4 +++ 2 files changed, 48 insertions(+), 19 deletions(-) diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c index 6d5a6cda0734..f1debe97dcfc 100644 --- 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 407a12f663eb..3bd0c59e1fb9 100644 --- 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, -- 2.20.1