From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yasuaki Ishimatsu Subject: Re: [RFC PATCH v3 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs Date: Tue, 17 Jul 2012 09:30:11 +0900 Message-ID: <5004B213.8010304@jp.fujitsu.com> References: <4FFAB0A2.8070304@jp.fujitsu.com> <4FFAB1BA.9040801@jp.fujitsu.com> <50037D3A.4090309@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-2022-JP" Content-Transfer-Encoding: 7bit Return-path: Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:54111 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751804Ab2GQAac (ORCPT ); Mon, 16 Jul 2012 20:30:32 -0400 In-Reply-To: <50037D3A.4090309@cn.fujitsu.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Wen Congyang Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-acpi@vger.kernel.org, rientjes@google.com, liuj97@gmail.com, len.brown@intel.com, benh@kernel.crashing.org, paulus@samba.org, cl@linux.com, minchan.kim@gmail.com, akpm@linux-foundation.org, kosaki.motohiro@jp.fujitsu.com Hi Wen, 2012/07/16 11:32, Wen Congyang wrote: > At 07/09/2012 06:26 PM, Yasuaki Ishimatsu Wrote: >> 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 since there is no way to free >> memory which is allocated by bootmem. >> >> CC: David Rientjes >> CC: Jiang Liu >> CC: Len Brown >> CC: Benjamin Herrenschmidt >> CC: Paul Mackerras >> CC: Christoph Lameter >> Cc: Minchan Kim >> CC: Andrew Morton >> CC: KOSAKI Motohiro >> CC: Wen Congyang >> Signed-off-by: Yasuaki Ishimatsu >> >> --- >> drivers/firmware/memmap.c | 78 ++++++++++++++++++++++++++++++++++++++++++- >> include/linux/firmware-map.h | 6 +++ >> mm/memory_hotplug.c | 6 ++- >> 3 files changed, 88 insertions(+), 2 deletions(-) >> >> Index: linux-3.5-rc6/mm/memory_hotplug.c >> =================================================================== >> --- linux-3.5-rc6.orig/mm/memory_hotplug.c 2012-07-09 18:23:13.323844923 +0900 >> +++ linux-3.5-rc6/mm/memory_hotplug.c 2012-07-09 18:23:19.522767424 +0900 >> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory); >> >> int remove_memory(int nid, u64 start, u64 size) >> { >> - return -EBUSY; >> + lock_memory_hotplug(); >> + /* remove memmap entry */ >> + firmware_map_remove(start, start + size - 1, "System RAM"); >> + unlock_memory_hotplug(); >> + return 0; >> >> } >> EXPORT_SYMBOL_GPL(remove_memory); >> Index: linux-3.5-rc6/include/linux/firmware-map.h >> =================================================================== >> --- linux-3.5-rc6.orig/include/linux/firmware-map.h 2012-07-09 18:23:09.532892314 +0900 >> +++ linux-3.5-rc6/include/linux/firmware-map.h 2012-07-09 18:23:19.523767412 +0900 >> @@ -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_hotpl >> 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 */ >> Index: linux-3.5-rc6/drivers/firmware/memmap.c >> =================================================================== >> --- linux-3.5-rc6.orig/drivers/firmware/memmap.c 2012-07-09 18:23:09.532892314 +0900 >> +++ linux-3.5-rc6/drivers/firmware/memmap.c 2012-07-09 18:25:46.371931554 +0900 >> @@ -21,6 +21,7 @@ >> #include >> #include >> #include >> +#include >> >> /* >> * Data types ------------------------------------------------------------------ >> @@ -79,7 +80,22 @@ static const struct sysfs_ops memmap_att >> .show = memmap_attr_show, >> }; >> >> +#define to_memmap_entry(obj) container_of(obj, struct firmware_map_entry, kobj) >> + >> +static void release_firmware_map_entry(struct kobject *kobj) >> +{ >> + struct firmware_map_entry *entry = to_memmap_entry(kobj); >> + struct page *head_page; >> + >> + head_page = virt_to_head_page(entry); >> + if (PageSlab(head_page)) >> + kfree(entry); >> + >> + /* There is no way to free memory allocated from bootmem*/ >> +} >> + >> static struct kobj_type memmap_ktype = { >> + .release = release_firmware_map_entry, >> .sysfs_ops = &memmap_attr_ops, >> .default_attrs = def_attrs, >> }; >> @@ -123,6 +139,16 @@ static int firmware_map_add_entry(u64 st >> 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) >> +{ >> + list_del(&entry->list); >> +} >> + >> /* >> * Add memmap entry on sysfs >> */ >> @@ -144,6 +170,31 @@ static int add_sysfs_fw_map_entry(struct >> 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 >> + */ >> + >> +struct firmware_map_entry * __meminit >> +find_firmware_map_entry(u64 start, u64 end, const char *type) >> +{ >> + struct firmware_map_entry *entry; >> + >> + list_for_each_entry(entry, &map_entries, list) >> + if ((entry->start == start) && (entry->end == end) && >> + (!strcmp(entry->type, type))) >> + return entry; >> + >> + return NULL; >> +} >> + >> /** >> * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do >> * memory hotplug. >> @@ -196,6 +247,32 @@ int __init firmware_map_add_early(u64 st >> 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 (inclusive). >> + * @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 = find_firmware_map_entry(start, end, type); >> + if (!entry) >> + return -EINVAL; >> + >> + /* remove the memmap entry */ >> + remove_sysfs_fw_map_entry(entry); >> + >> + firmware_map_remove_entry(entry); > > You should call firmware_map_remove_entry() before remove_sysfs_fw_map_entry(), > otherwise it will cause kernel panicked(entry may be freed in remove_sysfs_fw_map_entry()). You are right. I'll update it. Thanks, Yasuaki Ishimatsu > > Thanks > Wen Congyang > >> + >> + return 0; >> +} >> + >> /* >> * Sysfs functions ------------------------------------------------------------- >> */ >> @@ -218,7 +295,6 @@ static ssize_t type_show(struct firmware >> } >> >> #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 ssize_t memmap_attr_show(struct kobject *kobj, >> struct attribute *attr, char *buf) >> >> > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@kvack.org. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: email@kvack.org > From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753656Ab2GQAaf (ORCPT ); Mon, 16 Jul 2012 20:30:35 -0400 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:54111 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751804Ab2GQAac (ORCPT ); Mon, 16 Jul 2012 20:30:32 -0400 X-SecurityPolicyCheck: OK by SHieldMailChecker v1.7.4 Message-ID: <5004B213.8010304@jp.fujitsu.com> Date: Tue, 17 Jul 2012 09:30:11 +0900 From: Yasuaki Ishimatsu User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:13.0) Gecko/20120614 Thunderbird/13.0.1 MIME-Version: 1.0 To: Wen Congyang CC: , , , , , , , , , , , , Subject: Re: [RFC PATCH v3 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs References: <4FFAB0A2.8070304@jp.fujitsu.com> <4FFAB1BA.9040801@jp.fujitsu.com> <50037D3A.4090309@cn.fujitsu.com> In-Reply-To: <50037D3A.4090309@cn.fujitsu.com> Content-Type: text/plain; charset="ISO-2022-JP" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Wen, 2012/07/16 11:32, Wen Congyang wrote: > At 07/09/2012 06:26 PM, Yasuaki Ishimatsu Wrote: >> 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 since there is no way to free >> memory which is allocated by bootmem. >> >> CC: David Rientjes >> CC: Jiang Liu >> CC: Len Brown >> CC: Benjamin Herrenschmidt >> CC: Paul Mackerras >> CC: Christoph Lameter >> Cc: Minchan Kim >> CC: Andrew Morton >> CC: KOSAKI Motohiro >> CC: Wen Congyang >> Signed-off-by: Yasuaki Ishimatsu >> >> --- >> drivers/firmware/memmap.c | 78 ++++++++++++++++++++++++++++++++++++++++++- >> include/linux/firmware-map.h | 6 +++ >> mm/memory_hotplug.c | 6 ++- >> 3 files changed, 88 insertions(+), 2 deletions(-) >> >> Index: linux-3.5-rc6/mm/memory_hotplug.c >> =================================================================== >> --- linux-3.5-rc6.orig/mm/memory_hotplug.c 2012-07-09 18:23:13.323844923 +0900 >> +++ linux-3.5-rc6/mm/memory_hotplug.c 2012-07-09 18:23:19.522767424 +0900 >> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory); >> >> int remove_memory(int nid, u64 start, u64 size) >> { >> - return -EBUSY; >> + lock_memory_hotplug(); >> + /* remove memmap entry */ >> + firmware_map_remove(start, start + size - 1, "System RAM"); >> + unlock_memory_hotplug(); >> + return 0; >> >> } >> EXPORT_SYMBOL_GPL(remove_memory); >> Index: linux-3.5-rc6/include/linux/firmware-map.h >> =================================================================== >> --- linux-3.5-rc6.orig/include/linux/firmware-map.h 2012-07-09 18:23:09.532892314 +0900 >> +++ linux-3.5-rc6/include/linux/firmware-map.h 2012-07-09 18:23:19.523767412 +0900 >> @@ -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_hotpl >> 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 */ >> Index: linux-3.5-rc6/drivers/firmware/memmap.c >> =================================================================== >> --- linux-3.5-rc6.orig/drivers/firmware/memmap.c 2012-07-09 18:23:09.532892314 +0900 >> +++ linux-3.5-rc6/drivers/firmware/memmap.c 2012-07-09 18:25:46.371931554 +0900 >> @@ -21,6 +21,7 @@ >> #include >> #include >> #include >> +#include >> >> /* >> * Data types ------------------------------------------------------------------ >> @@ -79,7 +80,22 @@ static const struct sysfs_ops memmap_att >> .show = memmap_attr_show, >> }; >> >> +#define to_memmap_entry(obj) container_of(obj, struct firmware_map_entry, kobj) >> + >> +static void release_firmware_map_entry(struct kobject *kobj) >> +{ >> + struct firmware_map_entry *entry = to_memmap_entry(kobj); >> + struct page *head_page; >> + >> + head_page = virt_to_head_page(entry); >> + if (PageSlab(head_page)) >> + kfree(entry); >> + >> + /* There is no way to free memory allocated from bootmem*/ >> +} >> + >> static struct kobj_type memmap_ktype = { >> + .release = release_firmware_map_entry, >> .sysfs_ops = &memmap_attr_ops, >> .default_attrs = def_attrs, >> }; >> @@ -123,6 +139,16 @@ static int firmware_map_add_entry(u64 st >> 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) >> +{ >> + list_del(&entry->list); >> +} >> + >> /* >> * Add memmap entry on sysfs >> */ >> @@ -144,6 +170,31 @@ static int add_sysfs_fw_map_entry(struct >> 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 >> + */ >> + >> +struct firmware_map_entry * __meminit >> +find_firmware_map_entry(u64 start, u64 end, const char *type) >> +{ >> + struct firmware_map_entry *entry; >> + >> + list_for_each_entry(entry, &map_entries, list) >> + if ((entry->start == start) && (entry->end == end) && >> + (!strcmp(entry->type, type))) >> + return entry; >> + >> + return NULL; >> +} >> + >> /** >> * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do >> * memory hotplug. >> @@ -196,6 +247,32 @@ int __init firmware_map_add_early(u64 st >> 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 (inclusive). >> + * @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 = find_firmware_map_entry(start, end, type); >> + if (!entry) >> + return -EINVAL; >> + >> + /* remove the memmap entry */ >> + remove_sysfs_fw_map_entry(entry); >> + >> + firmware_map_remove_entry(entry); > > You should call firmware_map_remove_entry() before remove_sysfs_fw_map_entry(), > otherwise it will cause kernel panicked(entry may be freed in remove_sysfs_fw_map_entry()). You are right. I'll update it. Thanks, Yasuaki Ishimatsu > > Thanks > Wen Congyang > >> + >> + return 0; >> +} >> + >> /* >> * Sysfs functions ------------------------------------------------------------- >> */ >> @@ -218,7 +295,6 @@ static ssize_t type_show(struct firmware >> } >> >> #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 ssize_t memmap_attr_show(struct kobject *kobj, >> struct attribute *attr, char *buf) >> >> > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@kvack.org. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: email@kvack.org > From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx187.postini.com [74.125.245.187]) by kanga.kvack.org (Postfix) with SMTP id A22FC6B005A for ; Mon, 16 Jul 2012 20:30:35 -0400 (EDT) Received: from m4.gw.fujitsu.co.jp (unknown [10.0.50.74]) by fgwmail6.fujitsu.co.jp (Postfix) with ESMTP id 799AB3EE0C1 for ; Tue, 17 Jul 2012 09:30:33 +0900 (JST) Received: from smail (m4 [127.0.0.1]) by outgoing.m4.gw.fujitsu.co.jp (Postfix) with ESMTP id 59C1445DE55 for ; Tue, 17 Jul 2012 09:30:33 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (s4.gw.fujitsu.co.jp [10.0.50.94]) by m4.gw.fujitsu.co.jp (Postfix) with ESMTP id 2E1F445DE53 for ; Tue, 17 Jul 2012 09:30:33 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id 1E4B7E08005 for ; Tue, 17 Jul 2012 09:30:33 +0900 (JST) Received: from g01jpexchyt10.g01.fujitsu.local (g01jpexchyt10.g01.fujitsu.local [10.128.194.49]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id BA2AE1DB803B for ; Tue, 17 Jul 2012 09:30:32 +0900 (JST) Message-ID: <5004B213.8010304@jp.fujitsu.com> Date: Tue, 17 Jul 2012 09:30:11 +0900 From: Yasuaki Ishimatsu MIME-Version: 1.0 Subject: Re: [RFC PATCH v3 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs References: <4FFAB0A2.8070304@jp.fujitsu.com> <4FFAB1BA.9040801@jp.fujitsu.com> <50037D3A.4090309@cn.fujitsu.com> In-Reply-To: <50037D3A.4090309@cn.fujitsu.com> Content-Type: text/plain; charset="ISO-2022-JP" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Wen Congyang Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-acpi@vger.kernel.org, rientjes@google.com, liuj97@gmail.com, len.brown@intel.com, benh@kernel.crashing.org, paulus@samba.org, cl@linux.com, minchan.kim@gmail.com, akpm@linux-foundation.org, kosaki.motohiro@jp.fujitsu.com Hi Wen, 2012/07/16 11:32, Wen Congyang wrote: > At 07/09/2012 06:26 PM, Yasuaki Ishimatsu Wrote: >> 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 since there is no way to free >> memory which is allocated by bootmem. >> >> CC: David Rientjes >> CC: Jiang Liu >> CC: Len Brown >> CC: Benjamin Herrenschmidt >> CC: Paul Mackerras >> CC: Christoph Lameter >> Cc: Minchan Kim >> CC: Andrew Morton >> CC: KOSAKI Motohiro >> CC: Wen Congyang >> Signed-off-by: Yasuaki Ishimatsu >> >> --- >> drivers/firmware/memmap.c | 78 ++++++++++++++++++++++++++++++++++++++++++- >> include/linux/firmware-map.h | 6 +++ >> mm/memory_hotplug.c | 6 ++- >> 3 files changed, 88 insertions(+), 2 deletions(-) >> >> Index: linux-3.5-rc6/mm/memory_hotplug.c >> =================================================================== >> --- linux-3.5-rc6.orig/mm/memory_hotplug.c 2012-07-09 18:23:13.323844923 +0900 >> +++ linux-3.5-rc6/mm/memory_hotplug.c 2012-07-09 18:23:19.522767424 +0900 >> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory); >> >> int remove_memory(int nid, u64 start, u64 size) >> { >> - return -EBUSY; >> + lock_memory_hotplug(); >> + /* remove memmap entry */ >> + firmware_map_remove(start, start + size - 1, "System RAM"); >> + unlock_memory_hotplug(); >> + return 0; >> >> } >> EXPORT_SYMBOL_GPL(remove_memory); >> Index: linux-3.5-rc6/include/linux/firmware-map.h >> =================================================================== >> --- linux-3.5-rc6.orig/include/linux/firmware-map.h 2012-07-09 18:23:09.532892314 +0900 >> +++ linux-3.5-rc6/include/linux/firmware-map.h 2012-07-09 18:23:19.523767412 +0900 >> @@ -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_hotpl >> 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 */ >> Index: linux-3.5-rc6/drivers/firmware/memmap.c >> =================================================================== >> --- linux-3.5-rc6.orig/drivers/firmware/memmap.c 2012-07-09 18:23:09.532892314 +0900 >> +++ linux-3.5-rc6/drivers/firmware/memmap.c 2012-07-09 18:25:46.371931554 +0900 >> @@ -21,6 +21,7 @@ >> #include >> #include >> #include >> +#include >> >> /* >> * Data types ------------------------------------------------------------------ >> @@ -79,7 +80,22 @@ static const struct sysfs_ops memmap_att >> .show = memmap_attr_show, >> }; >> >> +#define to_memmap_entry(obj) container_of(obj, struct firmware_map_entry, kobj) >> + >> +static void release_firmware_map_entry(struct kobject *kobj) >> +{ >> + struct firmware_map_entry *entry = to_memmap_entry(kobj); >> + struct page *head_page; >> + >> + head_page = virt_to_head_page(entry); >> + if (PageSlab(head_page)) >> + kfree(entry); >> + >> + /* There is no way to free memory allocated from bootmem*/ >> +} >> + >> static struct kobj_type memmap_ktype = { >> + .release = release_firmware_map_entry, >> .sysfs_ops = &memmap_attr_ops, >> .default_attrs = def_attrs, >> }; >> @@ -123,6 +139,16 @@ static int firmware_map_add_entry(u64 st >> 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) >> +{ >> + list_del(&entry->list); >> +} >> + >> /* >> * Add memmap entry on sysfs >> */ >> @@ -144,6 +170,31 @@ static int add_sysfs_fw_map_entry(struct >> 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 >> + */ >> + >> +struct firmware_map_entry * __meminit >> +find_firmware_map_entry(u64 start, u64 end, const char *type) >> +{ >> + struct firmware_map_entry *entry; >> + >> + list_for_each_entry(entry, &map_entries, list) >> + if ((entry->start == start) && (entry->end == end) && >> + (!strcmp(entry->type, type))) >> + return entry; >> + >> + return NULL; >> +} >> + >> /** >> * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do >> * memory hotplug. >> @@ -196,6 +247,32 @@ int __init firmware_map_add_early(u64 st >> 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 (inclusive). >> + * @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 = find_firmware_map_entry(start, end, type); >> + if (!entry) >> + return -EINVAL; >> + >> + /* remove the memmap entry */ >> + remove_sysfs_fw_map_entry(entry); >> + >> + firmware_map_remove_entry(entry); > > You should call firmware_map_remove_entry() before remove_sysfs_fw_map_entry(), > otherwise it will cause kernel panicked(entry may be freed in remove_sysfs_fw_map_entry()). You are right. I'll update it. Thanks, Yasuaki Ishimatsu > > Thanks > Wen Congyang > >> + >> + return 0; >> +} >> + >> /* >> * Sysfs functions ------------------------------------------------------------- >> */ >> @@ -218,7 +295,6 @@ static ssize_t type_show(struct firmware >> } >> >> #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 ssize_t memmap_attr_show(struct kobject *kobj, >> struct attribute *attr, char *buf) >> >> > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@kvack.org. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: email@kvack.org > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from fgwmail5.fujitsu.co.jp (fgwmail5.fujitsu.co.jp [192.51.44.35]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 1CC182C0147 for ; Tue, 17 Jul 2012 10:30:33 +1000 (EST) Received: from m1.gw.fujitsu.co.jp (unknown [10.0.50.71]) by fgwmail5.fujitsu.co.jp (Postfix) with ESMTP id 5E26D3EE0BC for ; Tue, 17 Jul 2012 09:30:31 +0900 (JST) Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 40EFA45DE5C for ; Tue, 17 Jul 2012 09:30:31 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (s1.gw.fujitsu.co.jp [10.0.50.91]) by m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 2716E45DE54 for ; Tue, 17 Jul 2012 09:30:31 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 181321DB804B for ; Tue, 17 Jul 2012 09:30:31 +0900 (JST) Received: from g01jpexchyt10.g01.fujitsu.local (g01jpexchyt10.g01.fujitsu.local [10.128.194.49]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id BAC691DB8044 for ; Tue, 17 Jul 2012 09:30:30 +0900 (JST) Message-ID: <5004B213.8010304@jp.fujitsu.com> Date: Tue, 17 Jul 2012 09:30:11 +0900 From: Yasuaki Ishimatsu MIME-Version: 1.0 To: Wen Congyang Subject: Re: [RFC PATCH v3 4/13] memory-hotplug : remove /sys/firmware/memmap/X sysfs References: <4FFAB0A2.8070304@jp.fujitsu.com> <4FFAB1BA.9040801@jp.fujitsu.com> <50037D3A.4090309@cn.fujitsu.com> In-Reply-To: <50037D3A.4090309@cn.fujitsu.com> Content-Type: text/plain; charset="ISO-2022-JP" Cc: len.brown@intel.com, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, paulus@samba.org, minchan.kim@gmail.com, kosaki.motohiro@jp.fujitsu.com, rientjes@google.com, cl@linux.com, linuxppc-dev@lists.ozlabs.org, akpm@linux-foundation.org, liuj97@gmail.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi Wen, 2012/07/16 11:32, Wen Congyang wrote: > At 07/09/2012 06:26 PM, Yasuaki Ishimatsu Wrote: >> 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 since there is no way to free >> memory which is allocated by bootmem. >> >> CC: David Rientjes >> CC: Jiang Liu >> CC: Len Brown >> CC: Benjamin Herrenschmidt >> CC: Paul Mackerras >> CC: Christoph Lameter >> Cc: Minchan Kim >> CC: Andrew Morton >> CC: KOSAKI Motohiro >> CC: Wen Congyang >> Signed-off-by: Yasuaki Ishimatsu >> >> --- >> drivers/firmware/memmap.c | 78 ++++++++++++++++++++++++++++++++++++++++++- >> include/linux/firmware-map.h | 6 +++ >> mm/memory_hotplug.c | 6 ++- >> 3 files changed, 88 insertions(+), 2 deletions(-) >> >> Index: linux-3.5-rc6/mm/memory_hotplug.c >> =================================================================== >> --- linux-3.5-rc6.orig/mm/memory_hotplug.c 2012-07-09 18:23:13.323844923 +0900 >> +++ linux-3.5-rc6/mm/memory_hotplug.c 2012-07-09 18:23:19.522767424 +0900 >> @@ -661,7 +661,11 @@ EXPORT_SYMBOL_GPL(add_memory); >> >> int remove_memory(int nid, u64 start, u64 size) >> { >> - return -EBUSY; >> + lock_memory_hotplug(); >> + /* remove memmap entry */ >> + firmware_map_remove(start, start + size - 1, "System RAM"); >> + unlock_memory_hotplug(); >> + return 0; >> >> } >> EXPORT_SYMBOL_GPL(remove_memory); >> Index: linux-3.5-rc6/include/linux/firmware-map.h >> =================================================================== >> --- linux-3.5-rc6.orig/include/linux/firmware-map.h 2012-07-09 18:23:09.532892314 +0900 >> +++ linux-3.5-rc6/include/linux/firmware-map.h 2012-07-09 18:23:19.523767412 +0900 >> @@ -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_hotpl >> 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 */ >> Index: linux-3.5-rc6/drivers/firmware/memmap.c >> =================================================================== >> --- linux-3.5-rc6.orig/drivers/firmware/memmap.c 2012-07-09 18:23:09.532892314 +0900 >> +++ linux-3.5-rc6/drivers/firmware/memmap.c 2012-07-09 18:25:46.371931554 +0900 >> @@ -21,6 +21,7 @@ >> #include >> #include >> #include >> +#include >> >> /* >> * Data types ------------------------------------------------------------------ >> @@ -79,7 +80,22 @@ static const struct sysfs_ops memmap_att >> .show = memmap_attr_show, >> }; >> >> +#define to_memmap_entry(obj) container_of(obj, struct firmware_map_entry, kobj) >> + >> +static void release_firmware_map_entry(struct kobject *kobj) >> +{ >> + struct firmware_map_entry *entry = to_memmap_entry(kobj); >> + struct page *head_page; >> + >> + head_page = virt_to_head_page(entry); >> + if (PageSlab(head_page)) >> + kfree(entry); >> + >> + /* There is no way to free memory allocated from bootmem*/ >> +} >> + >> static struct kobj_type memmap_ktype = { >> + .release = release_firmware_map_entry, >> .sysfs_ops = &memmap_attr_ops, >> .default_attrs = def_attrs, >> }; >> @@ -123,6 +139,16 @@ static int firmware_map_add_entry(u64 st >> 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) >> +{ >> + list_del(&entry->list); >> +} >> + >> /* >> * Add memmap entry on sysfs >> */ >> @@ -144,6 +170,31 @@ static int add_sysfs_fw_map_entry(struct >> 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 >> + */ >> + >> +struct firmware_map_entry * __meminit >> +find_firmware_map_entry(u64 start, u64 end, const char *type) >> +{ >> + struct firmware_map_entry *entry; >> + >> + list_for_each_entry(entry, &map_entries, list) >> + if ((entry->start == start) && (entry->end == end) && >> + (!strcmp(entry->type, type))) >> + return entry; >> + >> + return NULL; >> +} >> + >> /** >> * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do >> * memory hotplug. >> @@ -196,6 +247,32 @@ int __init firmware_map_add_early(u64 st >> 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 (inclusive). >> + * @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 = find_firmware_map_entry(start, end, type); >> + if (!entry) >> + return -EINVAL; >> + >> + /* remove the memmap entry */ >> + remove_sysfs_fw_map_entry(entry); >> + >> + firmware_map_remove_entry(entry); > > You should call firmware_map_remove_entry() before remove_sysfs_fw_map_entry(), > otherwise it will cause kernel panicked(entry may be freed in remove_sysfs_fw_map_entry()). You are right. I'll update it. Thanks, Yasuaki Ishimatsu > > Thanks > Wen Congyang > >> + >> + return 0; >> +} >> + >> /* >> * Sysfs functions ------------------------------------------------------------- >> */ >> @@ -218,7 +295,6 @@ static ssize_t type_show(struct firmware >> } >> >> #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 ssize_t memmap_attr_show(struct kobject *kobj, >> struct attribute *attr, char *buf) >> >> > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@kvack.org. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: email@kvack.org >