diff options
Diffstat (limited to 'drivers/acpi/acpica/tbxface.c')
-rw-r--r-- | drivers/acpi/acpica/tbxface.c | 130 |
1 files changed, 82 insertions, 48 deletions
diff --git a/drivers/acpi/acpica/tbxface.c b/drivers/acpi/acpica/tbxface.c index d5adb7ac4684..7684707b254b 100644 --- a/drivers/acpi/acpica/tbxface.c +++ b/drivers/acpi/acpica/tbxface.c @@ -282,7 +282,7 @@ ACPI_EXPORT_SYMBOL(acpi_get_table_header) /******************************************************************************* * - * FUNCTION: acpi_get_table_with_size + * FUNCTION: acpi_get_table * * PARAMETERS: signature - ACPI signature of needed table * instance - Which instance (for SSDTs) @@ -292,16 +292,21 @@ ACPI_EXPORT_SYMBOL(acpi_get_table_header) * * DESCRIPTION: Finds and verifies an ACPI table. Table must be in the * RSDT/XSDT. + * Note that an early stage acpi_get_table() call must be paired + * with an early stage acpi_put_table() call. otherwise the table + * pointer mapped by the early stage mapping implementation may be + * erroneously unmapped by the late stage unmapping implementation + * in an acpi_put_table() invoked during the late stage. * ******************************************************************************/ acpi_status -acpi_get_table_with_size(char *signature, - u32 instance, struct acpi_table_header **out_table, - acpi_size *tbl_size) +acpi_get_table(char *signature, + u32 instance, struct acpi_table_header ** out_table) { u32 i; u32 j; - acpi_status status; + acpi_status status = AE_NOT_FOUND; + struct acpi_table_desc *table_desc; /* Parameter validation */ @@ -309,13 +314,22 @@ acpi_get_table_with_size(char *signature, return (AE_BAD_PARAMETER); } + /* + * Note that the following line is required by some OSPMs, they only + * check if the returned table is NULL instead of the returned status + * to determined if this function is succeeded. + */ + *out_table = NULL; + + (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES); + /* Walk the root table list */ for (i = 0, j = 0; i < acpi_gbl_root_table_list.current_table_count; i++) { - if (!ACPI_COMPARE_NAME - (&(acpi_gbl_root_table_list.tables[i].signature), - signature)) { + table_desc = &acpi_gbl_root_table_list.tables[i]; + + if (!ACPI_COMPARE_NAME(&table_desc->signature, signature)) { continue; } @@ -323,43 +337,65 @@ acpi_get_table_with_size(char *signature, continue; } - status = - acpi_tb_validate_table(&acpi_gbl_root_table_list.tables[i]); - if (ACPI_SUCCESS(status)) { - *out_table = acpi_gbl_root_table_list.tables[i].pointer; - *tbl_size = acpi_gbl_root_table_list.tables[i].length; - } - - if (!acpi_gbl_permanent_mmap) { - acpi_gbl_root_table_list.tables[i].pointer = NULL; - } - - return (status); + status = acpi_tb_get_table(table_desc, out_table); + break; } - return (AE_NOT_FOUND); + (void)acpi_ut_release_mutex(ACPI_MTX_TABLES); + return (status); } -ACPI_EXPORT_SYMBOL(acpi_get_table_with_size) +ACPI_EXPORT_SYMBOL(acpi_get_table) -acpi_status -acpi_get_table(char *signature, - u32 instance, struct acpi_table_header **out_table) +/******************************************************************************* + * + * FUNCTION: acpi_put_table + * + * PARAMETERS: table - The pointer to the table + * + * RETURN: None + * + * DESCRIPTION: Release a table returned by acpi_get_table() and its clones. + * Note that it is not safe if this function was invoked after an + * uninstallation happened to the original table descriptor. + * Currently there is no OSPMs' requirement to handle such + * situations. + * + ******************************************************************************/ +void acpi_put_table(struct acpi_table_header *table) { - acpi_size tbl_size; + u32 i; + struct acpi_table_desc *table_desc; + + ACPI_FUNCTION_TRACE(acpi_put_table); + + (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES); + + /* Walk the root table list */ + + for (i = 0; i < acpi_gbl_root_table_list.current_table_count; i++) { + table_desc = &acpi_gbl_root_table_list.tables[i]; - return acpi_get_table_with_size(signature, - instance, out_table, &tbl_size); + if (table_desc->pointer != table) { + continue; + } + + acpi_tb_put_table(table_desc); + break; + } + + (void)acpi_ut_release_mutex(ACPI_MTX_TABLES); + return_VOID; } -ACPI_EXPORT_SYMBOL(acpi_get_table) +ACPI_EXPORT_SYMBOL(acpi_put_table) /******************************************************************************* * * FUNCTION: acpi_get_table_by_index * * PARAMETERS: table_index - Table index - * table - Where the pointer to the table is returned + * out_table - Where the pointer to the table is returned * * RETURN: Status and pointer to the requested table * @@ -368,7 +404,7 @@ ACPI_EXPORT_SYMBOL(acpi_get_table) * ******************************************************************************/ acpi_status -acpi_get_table_by_index(u32 table_index, struct acpi_table_header **table) +acpi_get_table_by_index(u32 table_index, struct acpi_table_header **out_table) { acpi_status status; @@ -376,35 +412,33 @@ acpi_get_table_by_index(u32 table_index, struct acpi_table_header **table) /* Parameter validation */ - if (!table) { + if (!out_table) { return_ACPI_STATUS(AE_BAD_PARAMETER); } + /* + * Note that the following line is required by some OSPMs, they only + * check if the returned table is NULL instead of the returned status + * to determined if this function is succeeded. + */ + *out_table = NULL; + (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES); /* Validate index */ if (table_index >= acpi_gbl_root_table_list.current_table_count) { - (void)acpi_ut_release_mutex(ACPI_MTX_TABLES); - return_ACPI_STATUS(AE_BAD_PARAMETER); + status = AE_BAD_PARAMETER; + goto unlock_and_exit; } - if (!acpi_gbl_root_table_list.tables[table_index].pointer) { - - /* Table is not mapped, map it */ + status = + acpi_tb_get_table(&acpi_gbl_root_table_list.tables[table_index], + out_table); - status = - acpi_tb_validate_table(&acpi_gbl_root_table_list. - tables[table_index]); - if (ACPI_FAILURE(status)) { - (void)acpi_ut_release_mutex(ACPI_MTX_TABLES); - return_ACPI_STATUS(status); - } - } - - *table = acpi_gbl_root_table_list.tables[table_index].pointer; +unlock_and_exit: (void)acpi_ut_release_mutex(ACPI_MTX_TABLES); - return_ACPI_STATUS(AE_OK); + return_ACPI_STATUS(status); } ACPI_EXPORT_SYMBOL(acpi_get_table_by_index) |