From patchwork Fri Jun 26 17:31:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rafael J. Wysocki" X-Patchwork-Id: 11628115 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 62A396C1 for ; Fri, 26 Jun 2020 17:34:18 +0000 (UTC) Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4C3B120707 for ; Fri, 26 Jun 2020 17:34:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4C3B120707 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=rjwysocki.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvdimm-bounces@lists.01.org Received: from ml01.vlan13.01.org (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id B5609110122B6; Fri, 26 Jun 2020 10:34:17 -0700 (PDT) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=79.96.170.134; helo=cloudserver094114.home.pl; envelope-from=rjw@rjwysocki.net; receiver= Received: from cloudserver094114.home.pl (cloudserver094114.home.pl [79.96.170.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 61FA510FE3541 for ; Fri, 26 Jun 2020 10:34:15 -0700 (PDT) Received: from 89-64-83-223.dynamic.chello.pl (89.64.83.223) (HELO kreacher.localnet) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.83.415) id 85d3147370415763; Fri, 26 Jun 2020 19:34:13 +0200 From: "Rafael J. Wysocki" To: Dan Williams , Erik Kaneda Subject: [RFT][PATCH v3 2/4] ACPI: OSL: Implement deferred unmapping of ACPI memory Date: Fri, 26 Jun 2020 19:31:24 +0200 Message-ID: <4507864.RZ40Oy75i1@kreacher> In-Reply-To: <2788992.3K7huLjdjL@kreacher> References: <158889473309.2292982.18007035454673387731.stgit@dwillia2-desk3.amr.corp.intel.com> <2713141.s8EVnczdoM@kreacher> <2788992.3K7huLjdjL@kreacher> MIME-Version: 1.0 Message-ID-Hash: RKIONUBWARFHTU25TEUCMMYWWTYK5SJZ X-Message-ID-Hash: RKIONUBWARFHTU25TEUCMMYWWTYK5SJZ X-MailFrom: rjw@rjwysocki.net X-Mailman-Rule-Hits: nonmember-moderation X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation CC: rafael.j.wysocki@intel.com, Len Brown , Borislav Petkov , James Morse , Myron Stowe , Andy Shevchenko , linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, linux-nvdimm@lists.01.org, Bob Moore X-Mailman-Version: 3.1.1 Precedence: list List-Id: "Linux-nvdimm developer list." Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: From: "Rafael J. Wysocki" Rework acpi_os_unmap_memory() so that it does not release the memory mapping matching the given address range right away but queues it up for later removal, implement acpi_os_release_unused_mappings() that will remove the unused ACPI memory mappings and add invocations of it to acpi_release_memory() and to the table loading/unloading code, to get rid of memory mappings that may be left behind. Reported-by: Dan Williams Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpi_configfs.c | 3 + drivers/acpi/osl.c | 153 +++++++++++++++++++++++------- drivers/acpi/tables.c | 2 + include/acpi/platform/aclinux.h | 1 + include/acpi/platform/aclinuxex.h | 2 + 5 files changed, 125 insertions(+), 36 deletions(-) diff --git a/drivers/acpi/acpi_configfs.c b/drivers/acpi/acpi_configfs.c index ece8c1a921cc..dd167ff87dc4 100644 --- a/drivers/acpi/acpi_configfs.c +++ b/drivers/acpi/acpi_configfs.c @@ -59,6 +59,8 @@ static ssize_t acpi_table_aml_write(struct config_item *cfg, table->header = NULL; } + acpi_os_release_unused_mappings(); + return ret; } @@ -224,6 +226,7 @@ static void acpi_table_drop_item(struct config_group *group, ACPI_INFO(("Host-directed Dynamic ACPI Table Unload")); acpi_unload_table(table->index); + acpi_os_release_unused_mappings(); } static struct configfs_group_operations acpi_table_group_ops = { diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index 762c5d50b8fe..749ae3e32193 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -77,12 +77,16 @@ struct acpi_ioremap { void __iomem *virt; acpi_physical_address phys; acpi_size size; - unsigned long refcount; + union { + unsigned long refcount; + struct list_head gc; + } track; }; static LIST_HEAD(acpi_ioremaps); static DEFINE_MUTEX(acpi_ioremap_lock); #define acpi_ioremap_lock_held() lock_is_held(&acpi_ioremap_lock.dep_map) +static LIST_HEAD(unused_mappings); static void __init acpi_request_region (struct acpi_generic_address *gas, unsigned int length, char *desc) @@ -250,7 +254,7 @@ void __iomem *acpi_os_get_iomem(acpi_physical_address phys, unsigned int size) map = acpi_map_lookup(phys, size); if (map) { virt = map->virt + (phys - map->phys); - map->refcount++; + map->track.refcount++; } mutex_unlock(&acpi_ioremap_lock); return virt; @@ -335,7 +339,7 @@ void __iomem __ref /* Check if there's a suitable mapping already. */ map = acpi_map_lookup(phys, size); if (map) { - map->refcount++; + map->track.refcount++; goto out; } @@ -358,7 +362,7 @@ void __iomem __ref map->virt = virt; map->phys = pg_off; map->size = pg_sz; - map->refcount = 1; + map->track.refcount = 1; list_add_tail_rcu(&map->list, &acpi_ioremaps); @@ -375,40 +379,39 @@ void *__ref acpi_os_map_memory(acpi_physical_address phys, acpi_size size) EXPORT_SYMBOL_GPL(acpi_os_map_memory); /* Must be called with mutex_lock(&acpi_ioremap_lock) */ -static unsigned long acpi_os_drop_map_ref(struct acpi_ioremap *map) +static bool acpi_os_drop_map_ref(struct acpi_ioremap *map, bool defer) { - unsigned long refcount = --map->refcount; + if (--map->track.refcount) + return true; - if (!refcount) - list_del_rcu(&map->list); - return refcount; + list_del_rcu(&map->list); + + if (defer) { + INIT_LIST_HEAD(&map->track.gc); + list_add_tail(&map->track.gc, &unused_mappings); + } + return defer; } -static void acpi_os_map_cleanup(struct acpi_ioremap *map) +static void __acpi_os_map_cleanup(struct acpi_ioremap *map) { - synchronize_rcu_expedited(); acpi_unmap(map->phys, map->virt); kfree(map); } -/** - * acpi_os_unmap_iomem - Drop a memory mapping reference. - * @virt: Start of the address range to drop a reference to. - * @size: Size of the address range to drop a reference to. - * - * Look up the given virtual address range in the list of existing ACPI memory - * mappings, drop a reference to it and unmap it if there are no more active - * references to it. - * - * During early init (when acpi_permanent_mmap has not been set yet) this - * routine simply calls __acpi_unmap_table() to get the job done. Since - * __acpi_unmap_table() is an __init function, the __ref annotation is needed - * here. - */ -void __ref acpi_os_unmap_iomem(void __iomem *virt, acpi_size size) +static void acpi_os_map_cleanup(struct acpi_ioremap *map) +{ + if (!map) + return; + + synchronize_rcu_expedited(); + __acpi_os_map_cleanup(map); +} + +static void __ref __acpi_os_unmap_iomem(void __iomem *virt, acpi_size size, + bool defer) { struct acpi_ioremap *map; - unsigned long refcount; if (!acpi_permanent_mmap) { __acpi_unmap_table(virt, size); @@ -416,26 +419,97 @@ void __ref acpi_os_unmap_iomem(void __iomem *virt, acpi_size size) } mutex_lock(&acpi_ioremap_lock); + map = acpi_map_lookup_virt(virt, size); if (!map) { mutex_unlock(&acpi_ioremap_lock); WARN(true, PREFIX "%s: bad address %p\n", __func__, virt); return; } - refcount = acpi_os_drop_map_ref(map); + if (acpi_os_drop_map_ref(map, defer)) + map = NULL; + mutex_unlock(&acpi_ioremap_lock); - if (!refcount) - acpi_os_map_cleanup(map); + acpi_os_map_cleanup(map); +} + +/** + * acpi_os_unmap_iomem - Drop a memory mapping reference. + * @virt: Start of the address range to drop a reference to. + * @size: Size of the address range to drop a reference to. + * + * Look up the given virtual address range in the list of existing ACPI memory + * mappings, drop a reference to it and unmap it if there are no more active + * references to it. + * + * During early init (when acpi_permanent_mmap has not been set yet) this + * routine simply calls __acpi_unmap_table() to get the job done. Since + * __acpi_unmap_table() is an __init function, the __ref annotation is needed + * here. + */ +void __ref acpi_os_unmap_iomem(void __iomem *virt, acpi_size size) +{ + __acpi_os_unmap_iomem(virt, size, false); } EXPORT_SYMBOL_GPL(acpi_os_unmap_iomem); +/** + * acpi_os_unmap_memory - Drop a memory mapping reference. + * @virt: Start of the address range to drop a reference to. + * @size: Size of the address range to drop a reference to. + * + * Look up the given virtual address range in the list of existing ACPI memory + * mappings, drop a reference to it and if there are no more active references + * to it, put it in the list of unused memory mappings. + * + * During early init (when acpi_permanent_mmap has not been set yet) this + * routine behaves like acpi_os_unmap_iomem(). + */ void __ref acpi_os_unmap_memory(void *virt, acpi_size size) { - return acpi_os_unmap_iomem((void __iomem *)virt, size); + __acpi_os_unmap_iomem((void __iomem *)virt, size, true); } EXPORT_SYMBOL_GPL(acpi_os_unmap_memory); +/** + * acpi_os_release_unused_mappings - Release unused ACPI memory mappings. + */ +void acpi_os_release_unused_mappings(void) +{ + struct list_head list; + + INIT_LIST_HEAD(&list); + + /* + * First avoid looking at mappings that may be added to the "unused" + * list while the synchronize_rcu() below is running. + */ + mutex_lock(&acpi_ioremap_lock); + + list_splice_init(&unused_mappings, &list); + + mutex_unlock(&acpi_ioremap_lock); + + if (list_empty(&list)) + return; + + /* + * Wait for the possible users of the mappings in the "unused" list to + * stop using them. + */ + synchronize_rcu(); + + /* Release the unused mappings in the list. */ + do { + struct acpi_ioremap *map; + + map = list_entry(list.next, struct acpi_ioremap, track.gc); + list_del(&map->track.gc); + __acpi_os_map_cleanup(map); + } while (!list_empty(&list)); +} + int acpi_os_map_generic_address(struct acpi_generic_address *gas) { u64 addr; @@ -461,7 +535,6 @@ void acpi_os_unmap_generic_address(struct acpi_generic_address *gas) { u64 addr; struct acpi_ioremap *map; - unsigned long refcount; if (gas->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY) return; @@ -472,16 +545,18 @@ void acpi_os_unmap_generic_address(struct acpi_generic_address *gas) return; mutex_lock(&acpi_ioremap_lock); + map = acpi_map_lookup(addr, gas->bit_width / 8); if (!map) { mutex_unlock(&acpi_ioremap_lock); return; } - refcount = acpi_os_drop_map_ref(map); + if (acpi_os_drop_map_ref(map, false)) + map = NULL; + mutex_unlock(&acpi_ioremap_lock); - if (!refcount) - acpi_os_map_cleanup(map); + acpi_os_map_cleanup(map); } EXPORT_SYMBOL(acpi_os_unmap_generic_address); @@ -1566,11 +1641,17 @@ static acpi_status acpi_deactivate_mem_region(acpi_handle handle, u32 level, acpi_status acpi_release_memory(acpi_handle handle, struct resource *res, u32 level) { + acpi_status ret; + if (!(res->flags & IORESOURCE_MEM)) return AE_TYPE; - return acpi_walk_namespace(ACPI_TYPE_REGION, handle, level, + ret = acpi_walk_namespace(ACPI_TYPE_REGION, handle, level, acpi_deactivate_mem_region, NULL, res, NULL); + + acpi_os_release_unused_mappings(); + + return ret; } EXPORT_SYMBOL_GPL(acpi_release_memory); diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c index 0e905c3d1645..939484a860a1 100644 --- a/drivers/acpi/tables.c +++ b/drivers/acpi/tables.c @@ -816,6 +816,8 @@ int __init acpi_table_init(void) return -EINVAL; acpi_table_initrd_scan(); + acpi_os_release_unused_mappings(); + check_multiple_madt(); return 0; } diff --git a/include/acpi/platform/aclinux.h b/include/acpi/platform/aclinux.h index 987e2af7c335..784e294dc74c 100644 --- a/include/acpi/platform/aclinux.h +++ b/include/acpi/platform/aclinux.h @@ -133,6 +133,7 @@ #define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_delete_raw_lock #define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_acquire_raw_lock #define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_release_raw_lock +#define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_release_unused_mappings /* * OSL interfaces used by debugger/disassembler diff --git a/include/acpi/platform/aclinuxex.h b/include/acpi/platform/aclinuxex.h index 04f88f2de781..ad6b905358c5 100644 --- a/include/acpi/platform/aclinuxex.h +++ b/include/acpi/platform/aclinuxex.h @@ -120,6 +120,8 @@ static inline void acpi_os_delete_raw_lock(acpi_raw_spinlock handle) ACPI_FREE(handle); } +void acpi_os_release_unused_mappings(void); + static inline u8 acpi_os_readable(void *pointer, acpi_size length) { return TRUE;