| Message ID | 4FFAB1BA.9040801@jp.fujitsu.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
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 <rientjes@google.com> > CC: Jiang Liu <liuj97@gmail.com> > CC: Len Brown <len.brown@intel.com> > CC: Benjamin Herrenschmidt <benh@kernel.crashing.org> > CC: Paul Mackerras <paulus@samba.org> > CC: Christoph Lameter <cl@linux.com> > Cc: Minchan Kim <minchan.kim@gmail.com> > CC: Andrew Morton <akpm@linux-foundation.org> > CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> > CC: Wen Congyang <wency@cn.fujitsu.com> > Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> > > --- > 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"); firmware_map_remove() is in meminit section, so remove_memory() should be in ref section. Thanks Wen Congyang > + 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 <linux/types.h> > #include <linux/bootmem.h> > #include <linux/slab.h> > +#include <linux/mm.h> > > /* > * 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); > + > + 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) > >
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 <rientjes@google.com> > CC: Jiang Liu <liuj97@gmail.com> > CC: Len Brown <len.brown@intel.com> > CC: Benjamin Herrenschmidt <benh@kernel.crashing.org> > CC: Paul Mackerras <paulus@samba.org> > CC: Christoph Lameter <cl@linux.com> > Cc: Minchan Kim <minchan.kim@gmail.com> > CC: Andrew Morton <akpm@linux-foundation.org> > CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> > CC: Wen Congyang <wency@cn.fujitsu.com> > Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> > > --- > 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 <linux/types.h> > #include <linux/bootmem.h> > #include <linux/slab.h> > +#include <linux/mm.h> > > /* > * 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()). 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) > >
Hi Wen, 2012/07/13 18:10, 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 <rientjes@google.com> >> CC: Jiang Liu <liuj97@gmail.com> >> CC: Len Brown <len.brown@intel.com> >> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org> >> CC: Paul Mackerras <paulus@samba.org> >> CC: Christoph Lameter <cl@linux.com> >> Cc: Minchan Kim <minchan.kim@gmail.com> >> CC: Andrew Morton <akpm@linux-foundation.org> >> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> >> CC: Wen Congyang <wency@cn.fujitsu.com> >> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> >> >> --- >> 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"); > > firmware_map_remove() is in meminit section, so remove_memory() should be in > ref section. I'll add it. Thanks, Yasuaki Ishimatsu > > Thanks > Wen Congyang > >> + 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 <linux/types.h> >> #include <linux/bootmem.h> >> #include <linux/slab.h> >> +#include <linux/mm.h> >> >> /* >> * 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); >> + >> + 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: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> >
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 <rientjes@google.com> >> CC: Jiang Liu <liuj97@gmail.com> >> CC: Len Brown <len.brown@intel.com> >> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org> >> CC: Paul Mackerras <paulus@samba.org> >> CC: Christoph Lameter <cl@linux.com> >> Cc: Minchan Kim <minchan.kim@gmail.com> >> CC: Andrew Morton <akpm@linux-foundation.org> >> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> >> CC: Wen Congyang <wency@cn.fujitsu.com> >> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> >> >> --- >> 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 <linux/types.h> >> #include <linux/bootmem.h> >> #include <linux/slab.h> >> +#include <linux/mm.h> >> >> /* >> * 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: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> >
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 <linux/types.h> #include <linux/bootmem.h> #include <linux/slab.h> +#include <linux/mm.h> /* * 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); + + 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)
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 <rientjes@google.com> CC: Jiang Liu <liuj97@gmail.com> CC: Len Brown <len.brown@intel.com> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org> CC: Paul Mackerras <paulus@samba.org> CC: Christoph Lameter <cl@linux.com> Cc: Minchan Kim <minchan.kim@gmail.com> CC: Andrew Morton <akpm@linux-foundation.org> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> CC: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> --- drivers/firmware/memmap.c | 78 ++++++++++++++++++++++++++++++++++++++++++- include/linux/firmware-map.h | 6 +++ mm/memory_hotplug.c | 6 ++- 3 files changed, 88 insertions(+), 2 deletions(-)