From patchwork Wed Jan 9 09:32:28 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tang Chen X-Patchwork-Id: 210648 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from ozlabs.org (localhost [IPv6:::1]) by ozlabs.org (Postfix) with ESMTP id 6FD622C0436 for ; Wed, 9 Jan 2013 20:34:47 +1100 (EST) Received: from song.cn.fujitsu.com (unknown [222.73.24.84]) by ozlabs.org (Postfix) with ESMTP id 1DCAE2C00D2 for ; Wed, 9 Jan 2013 20:33:35 +1100 (EST) X-IronPort-AV: E=Sophos;i="4.84,437,1355068800"; d="scan'208";a="6551287" Received: from unknown (HELO tang.cn.fujitsu.com) ([10.167.250.3]) by song.cn.fujitsu.com with ESMTP; 09 Jan 2013 17:31:29 +0800 Received: from fnstmail02.fnst.cn.fujitsu.com (tang.cn.fujitsu.com [127.0.0.1]) by tang.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id r099XQe0028270; Wed, 9 Jan 2013 17:33:27 +0800 Received: from tangchen.fnst.cn.fujitsu.com ([10.167.225.117]) by fnstmail02.fnst.cn.fujitsu.com (Lotus Domino Release 8.5.3) with ESMTP id 2013010917325308-803900 ; Wed, 9 Jan 2013 17:32:53 +0800 From: Tang Chen To: akpm@linux-foundation.org, rientjes@google.com, len.brown@intel.com, benh@kernel.crashing.org, paulus@samba.org, cl@linux.com, minchan.kim@gmail.com, kosaki.motohiro@jp.fujitsu.com, isimatu.yasuaki@jp.fujitsu.com, wujianguo@huawei.com, wency@cn.fujitsu.com, tangchen@cn.fujitsu.com, hpa@zytor.com, linfeng@cn.fujitsu.com, laijs@cn.fujitsu.com, mgorman@suse.de, yinghai@kernel.org, glommer@parallels.com Subject: [PATCH v6 04/15] memory-hotplug: remove /sys/firmware/memmap/X sysfs Date: Wed, 9 Jan 2013 17:32:28 +0800 Message-Id: <1357723959-5416-5-git-send-email-tangchen@cn.fujitsu.com> X-Mailer: git-send-email 1.7.10.1 In-Reply-To: <1357723959-5416-1-git-send-email-tangchen@cn.fujitsu.com> References: <1357723959-5416-1-git-send-email-tangchen@cn.fujitsu.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/01/09 17:32:53, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/01/09 17:32:58, Serialize complete at 2013/01/09 17:32:58 Cc: linux-s390@vger.kernel.org, linux-ia64@vger.kernel.org, linux-acpi@vger.kernel.org, linux-sh@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, cmetcalf@tilera.com, linux-mm@kvack.org, sparclinux@vger.kernel.org, linuxppc-dev@lists.ozlabs.org X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" From: Yasuaki Ishimatsu When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type} sysfs files are created. But there is no code to remove these files. The patch implements the function to remove them. Note: The code does not free firmware_map_entry which is allocated by bootmem. So the patch makes memory leak. But I think the memory leak size is very samll. And it does not affect the system. Signed-off-by: Wen Congyang Signed-off-by: Yasuaki Ishimatsu Signed-off-by: Tang Chen Reviewed-by: Kamezawa Hiroyuki --- drivers/firmware/memmap.c | 96 +++++++++++++++++++++++++++++++++++++++++- include/linux/firmware-map.h | 6 +++ mm/memory_hotplug.c | 5 ++- 3 files changed, 104 insertions(+), 3 deletions(-) diff --git a/drivers/firmware/memmap.c b/drivers/firmware/memmap.c index 90723e6..4211da5 100644 --- a/drivers/firmware/memmap.c +++ b/drivers/firmware/memmap.c @@ -21,6 +21,7 @@ #include #include #include +#include /* * Data types ------------------------------------------------------------------ @@ -79,7 +80,26 @@ static const struct sysfs_ops memmap_attr_ops = { .show = memmap_attr_show, }; + +static inline struct firmware_map_entry * +to_memmap_entry(struct kobject *kobj) +{ + return container_of(kobj, struct firmware_map_entry, kobj); +} + +static void release_firmware_map_entry(struct kobject *kobj) +{ + struct firmware_map_entry *entry = to_memmap_entry(kobj); + + if (PageReserved(virt_to_page(entry))) + /* There is no way to free memory allocated from bootmem */ + return; + + kfree(entry); +} + static struct kobj_type memmap_ktype = { + .release = release_firmware_map_entry, .sysfs_ops = &memmap_attr_ops, .default_attrs = def_attrs, }; @@ -94,6 +114,7 @@ static struct kobj_type memmap_ktype = { * in firmware initialisation code in one single thread of execution. */ static LIST_HEAD(map_entries); +static DEFINE_SPINLOCK(map_entries_lock); /** * firmware_map_add_entry() - Does the real work to add a firmware memmap entry. @@ -118,11 +139,25 @@ static int firmware_map_add_entry(u64 start, u64 end, INIT_LIST_HEAD(&entry->list); kobject_init(&entry->kobj, &memmap_ktype); + spin_lock(&map_entries_lock); list_add_tail(&entry->list, &map_entries); + spin_unlock(&map_entries_lock); return 0; } +/** + * firmware_map_remove_entry() - Does the real work to remove a firmware + * memmap entry. + * @entry: removed entry. + **/ +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry) +{ + spin_lock(&map_entries_lock); + list_del(&entry->list); + spin_unlock(&map_entries_lock); +} + /* * Add memmap entry on sysfs */ @@ -144,6 +179,35 @@ static int add_sysfs_fw_map_entry(struct firmware_map_entry *entry) return 0; } +/* + * Remove memmap entry on sysfs + */ +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry) +{ + kobject_put(&entry->kobj); +} + +/* + * Search memmap entry + */ + +static struct firmware_map_entry * __meminit +firmware_map_find_entry(u64 start, u64 end, const char *type) +{ + struct firmware_map_entry *entry; + + spin_lock(&map_entries_lock); + list_for_each_entry(entry, &map_entries, list) + if ((entry->start == start) && (entry->end == end) && + (!strcmp(entry->type, type))) { + spin_unlock(&map_entries_lock); + return entry; + } + + spin_unlock(&map_entries_lock); + return NULL; +} + /** * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do * memory hotplug. @@ -196,6 +260,32 @@ int __init firmware_map_add_early(u64 start, u64 end, const char *type) return firmware_map_add_entry(start, end, type, entry); } +/** + * firmware_map_remove() - remove a firmware mapping entry + * @start: Start of the memory range. + * @end: End of the memory range. + * @type: Type of the memory range. + * + * removes a firmware mapping entry. + * + * Returns 0 on success, or -EINVAL if no entry. + **/ +int __meminit firmware_map_remove(u64 start, u64 end, const char *type) +{ + struct firmware_map_entry *entry; + + entry = firmware_map_find_entry(start, end - 1, type); + if (!entry) + return -EINVAL; + + firmware_map_remove_entry(entry); + + /* remove the memmap entry */ + remove_sysfs_fw_map_entry(entry); + + return 0; +} + /* * Sysfs functions ------------------------------------------------------------- */ @@ -217,8 +307,10 @@ static ssize_t type_show(struct firmware_map_entry *entry, char *buf) return snprintf(buf, PAGE_SIZE, "%s\n", entry->type); } -#define to_memmap_attr(_attr) container_of(_attr, struct memmap_attribute, attr) -#define to_memmap_entry(obj) container_of(obj, struct firmware_map_entry, kobj) +static inline struct memmap_attribute *to_memmap_attr(struct attribute *attr) +{ + return container_of(attr, struct memmap_attribute, attr); +} static ssize_t memmap_attr_show(struct kobject *kobj, struct attribute *attr, char *buf) diff --git a/include/linux/firmware-map.h b/include/linux/firmware-map.h index 43fe52f..71d4fa7 100644 --- a/include/linux/firmware-map.h +++ b/include/linux/firmware-map.h @@ -25,6 +25,7 @@ int firmware_map_add_early(u64 start, u64 end, const char *type); int firmware_map_add_hotplug(u64 start, u64 end, const char *type); +int firmware_map_remove(u64 start, u64 end, const char *type); #else /* CONFIG_FIRMWARE_MEMMAP */ @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotplug(u64 start, u64 end, const char *type) return 0; } +static inline int firmware_map_remove(u64 start, u64 end, const char *type) +{ + return 0; +} + #endif /* CONFIG_FIRMWARE_MEMMAP */ #endif /* _LINUX_FIRMWARE_MAP_H */ diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 69d62eb..9fd5904 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1461,7 +1461,7 @@ static int is_memblock_offlined_cb(struct memory_block *mem, void *arg) return ret; } -int remove_memory(u64 start, u64 size) +int __ref remove_memory(u64 start, u64 size) { unsigned long start_pfn, end_pfn; int ret = 0; @@ -1511,6 +1511,9 @@ repeat: return ret; } + /* remove memmap entry */ + firmware_map_remove(start, start + size, "System RAM"); + unlock_memory_hotplug(); return 0;