Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752051AbdGDGOa (ORCPT ); Tue, 4 Jul 2017 02:14:30 -0400 Received: from david.siemens.de ([192.35.17.14]:37803 "EHLO david.siemens.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750921AbdGDGO3 (ORCPT ); Tue, 4 Jul 2017 02:14:29 -0400 Subject: Re: [PATCH v3] acpi: configfs: Unload SSDT on configfs entry removal From: Jan Kiszka To: "Rafael J. Wysocki" , Len Brown Cc: Lv Zheng , linux-acpi@vger.kernel.org, Linux Kernel Mailing List , devel@acpica.org, "Moore, Robert" References: Message-ID: Date: Tue, 4 Jul 2017 08:14:09 +0200 User-Agent: Mozilla/5.0 (X11; U; Linux i686 (x86_64); de; rv:1.8.1.12) Gecko/20080226 SUSE/2.0.0.12-1.1 Thunderbird/2.0.0.12 Mnenhy/0.7.5.666 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3339 Lines: 102 On 2017-06-09 20:36, Jan Kiszka wrote: > Call directly into acpica to load a table to obtain its index on return. > We choose the direct call of acpica internal functions to avoid having > to modify its API which is used outside of Linux as well. > > Use that index to unload the table again when the corresponding > directory in configfs gets removed. This allows to change SSDTs without > rebooting the system. It also allows to destroy devices again that a > dynamically loaded SSDT created. > > This is widely similar to the DT overlay behavior. > > Signed-off-by: Jan Kiszka > --- > > Change in v3: > - fix breakage if acpi_configfs is modular > > drivers/acpi/acpi_configfs.c | 20 +++++++++++++++++++- > drivers/acpi/acpica/tbdata.c | 4 ++++ > 2 files changed, 23 insertions(+), 1 deletion(-) > > diff --git a/drivers/acpi/acpi_configfs.c b/drivers/acpi/acpi_configfs.c > index 146a77fb762d..853bc7fc673f 100644 > --- a/drivers/acpi/acpi_configfs.c > +++ b/drivers/acpi/acpi_configfs.c > @@ -15,11 +15,15 @@ > #include > #include > > +#include "acpica/accommon.h" > +#include "acpica/actables.h" > + > static struct config_group *acpi_table_group; > > struct acpi_table { > struct config_item cfg; > struct acpi_table_header *header; > + u32 index; > }; > > static ssize_t acpi_table_aml_write(struct config_item *cfg, > @@ -52,7 +56,11 @@ static ssize_t acpi_table_aml_write(struct config_item *cfg, > if (!table->header) > return -ENOMEM; > > - ret = acpi_load_table(table->header); > + ACPI_INFO(("Host-directed Dynamic ACPI Table Load:")); > + ret = acpi_tb_install_and_load_table( > + ACPI_PTR_TO_PHYSADDR(table->header), > + ACPI_TABLE_ORIGIN_EXTERNAL_VIRTUAL, FALSE, > + &table->index); > if (ret) { > kfree(table->header); > table->header = NULL; > @@ -215,8 +223,18 @@ static struct config_item *acpi_table_make_item(struct config_group *group, > return &table->cfg; > } > > +static void acpi_table_drop_item(struct config_group *group, > + struct config_item *cfg) > +{ > + struct acpi_table *table = container_of(cfg, struct acpi_table, cfg); > + > + ACPI_INFO(("Host-directed Dynamic ACPI Table Unload")); > + acpi_tb_unload_table(table->index); > +} > + > struct configfs_group_operations acpi_table_group_ops = { > .make_item = acpi_table_make_item, > + .drop_item = acpi_table_drop_item, > }; > > static struct config_item_type acpi_tables_type = { > diff --git a/drivers/acpi/acpica/tbdata.c b/drivers/acpi/acpica/tbdata.c > index 27c5c27d4818..c9d6fa6d7cc6 100644 > --- a/drivers/acpi/acpica/tbdata.c > +++ b/drivers/acpi/acpica/tbdata.c > @@ -867,6 +867,8 @@ acpi_tb_install_and_load_table(acpi_physical_address address, > return_ACPI_STATUS(status); > } > > +ACPI_EXPORT_SYMBOL(acpi_tb_install_and_load_table) > + > /******************************************************************************* > * > * FUNCTION: acpi_tb_unload_table > @@ -914,3 +916,5 @@ acpi_status acpi_tb_unload_table(u32 table_index) > acpi_tb_set_table_loaded_flag(table_index, FALSE); > return_ACPI_STATUS(status); > } > + > +ACPI_EXPORT_SYMBOL(acpi_tb_unload_table) > Ping for this patch. Jan -- Siemens AG, Corporate Technology, CT RDA ITP SES-DE Corporate Competence Center Embedded Linux