From 8f6f03610483962a9ebfaf38592909a3f0bcfa53 Mon Sep 17 00:00:00 2001 From: Lv Zheng Date: Wed, 1 Jul 2015 14:44:17 +0800 Subject: [PATCH] ACPICA: Namespace: Add support to allow overriding objects ACPICA commit 6084e34e44565c6293f446c0202b5e59b055e351 This patch adds an "NamespaceOverride" flag in struct acpi_walk_state, and allows namespace objects to be overridden when this flag is set. Lv Zheng. Link: https://github.com/acpica/acpica/commit/6084e34e Signed-off-by: Lv Zheng Signed-off-by: Bob Moore Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpica/acnamesp.h | 1 + drivers/acpi/acpica/acstruct.h | 1 + drivers/acpi/acpica/dswload.c | 17 +++++++++++++---- drivers/acpi/acpica/nsaccess.c | 10 +++++++++- drivers/acpi/acpica/nssearch.c | 22 ++++++++++++++++++++-- 5 files changed, 44 insertions(+), 7 deletions(-) diff --git a/drivers/acpi/acpica/acnamesp.h b/drivers/acpi/acpica/acnamesp.h index 952fbe0b7231..0dd088290d80 100644 --- a/drivers/acpi/acpica/acnamesp.h +++ b/drivers/acpi/acpica/acnamesp.h @@ -66,6 +66,7 @@ #define ACPI_NS_PREFIX_IS_SCOPE 0x10 #define ACPI_NS_EXTERNAL 0x20 #define ACPI_NS_TEMPORARY 0x40 +#define ACPI_NS_OVERRIDE_IF_FOUND 0x80 /* Flags for acpi_ns_walk_namespace */ diff --git a/drivers/acpi/acpica/acstruct.h b/drivers/acpi/acpica/acstruct.h index 87c7860b3394..44997ca02ae2 100644 --- a/drivers/acpi/acpica/acstruct.h +++ b/drivers/acpi/acpica/acstruct.h @@ -82,6 +82,7 @@ struct acpi_walk_state { u8 return_used; u8 scope_depth; u8 pass_number; /* Parse pass during table load */ + u8 namespace_override; /* Override existing objects */ u8 result_size; /* Total elements for the result stack */ u8 result_count; /* Current number of occupied elements of result stack */ u32 aml_offset; diff --git a/drivers/acpi/acpica/dswload.c b/drivers/acpi/acpica/dswload.c index 843942fb4be5..845ff44919c3 100644 --- a/drivers/acpi/acpica/dswload.c +++ b/drivers/acpi/acpica/dswload.c @@ -315,10 +315,19 @@ acpi_ds_load1_begin_op(struct acpi_walk_state * walk_state, flags = ACPI_NS_NO_UPSEARCH; if ((walk_state->opcode != AML_SCOPE_OP) && (!(walk_state->parse_flags & ACPI_PARSE_DEFERRED_OP))) { - flags |= ACPI_NS_ERROR_IF_FOUND; - ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, - "[%s] Cannot already exist\n", - acpi_ut_get_type_name(object_type))); + if (walk_state->namespace_override) { + flags |= ACPI_NS_OVERRIDE_IF_FOUND; + ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, + "[%s] Override allowed\n", + acpi_ut_get_type_name + (object_type))); + } else { + flags |= ACPI_NS_ERROR_IF_FOUND; + ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, + "[%s] Cannot already exist\n", + acpi_ut_get_type_name + (object_type))); + } } else { ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "[%s] Both Find or Create allowed\n", diff --git a/drivers/acpi/acpica/nsaccess.c b/drivers/acpi/acpica/nsaccess.c index 24fa19a76d70..19ad0b5993d5 100644 --- a/drivers/acpi/acpica/nsaccess.c +++ b/drivers/acpi/acpica/nsaccess.c @@ -304,7 +304,9 @@ acpi_ns_lookup(union acpi_generic_state *scope_info, return_ACPI_STATUS(AE_BAD_PARAMETER); } - local_flags = flags & ~(ACPI_NS_ERROR_IF_FOUND | ACPI_NS_SEARCH_PARENT); + local_flags = flags & + ~(ACPI_NS_ERROR_IF_FOUND | ACPI_NS_OVERRIDE_IF_FOUND | + ACPI_NS_SEARCH_PARENT); *return_node = ACPI_ENTRY_NOT_FOUND; acpi_gbl_ns_lookup_count++; @@ -547,6 +549,12 @@ acpi_ns_lookup(union acpi_generic_state *scope_info, if (flags & ACPI_NS_ERROR_IF_FOUND) { local_flags |= ACPI_NS_ERROR_IF_FOUND; } + + /* Set override flag according to caller */ + + if (flags & ACPI_NS_OVERRIDE_IF_FOUND) { + local_flags |= ACPI_NS_OVERRIDE_IF_FOUND; + } } /* Extract one ACPI name from the front of the pathname */ diff --git a/drivers/acpi/acpica/nssearch.c b/drivers/acpi/acpica/nssearch.c index 4a9d4a66016e..47fbe5b33524 100644 --- a/drivers/acpi/acpica/nssearch.c +++ b/drivers/acpi/acpica/nssearch.c @@ -325,8 +325,26 @@ acpi_ns_search_and_enter(u32 target_name, * If we found it AND the request specifies that a find is an error, * return the error */ - if ((status == AE_OK) && (flags & ACPI_NS_ERROR_IF_FOUND)) { - status = AE_ALREADY_EXISTS; + if (status == AE_OK) { + + /* The node was found in the namespace */ + + /* + * If the namespace override feature is enabled for this node, + * delete any existing node. This can only happen during the + * boot stage, thus it is safe to remove the node here. + */ + if (flags & ACPI_NS_OVERRIDE_IF_FOUND) { + acpi_ns_delete_children(*return_node); + acpi_ns_remove_node(*return_node); + *return_node = ACPI_ENTRY_NOT_FOUND; + } + + /* Return an error if we don't expect to find the object */ + + else if (flags & ACPI_NS_ERROR_IF_FOUND) { + status = AE_ALREADY_EXISTS; + } } #ifdef ACPI_ASL_COMPILER if (*return_node && (*return_node)->type == ACPI_TYPE_ANY) { -- 2.20.1