diff options
| author | Badari Pulavarty <pbadari@us.ibm.com> | 2008-02-05 00:10:18 -0800 |
|---|---|---|
| committer | Paul Mackerras <paulus@samba.org> | 2008-02-08 19:52:48 +1100 |
| commit | a99824f327c748b2753f4fa570eb1fefcd6a9c4d (patch) | |
| tree | 47c6df061ade21ce7ebae43b31a39e882c90cf2b /arch | |
| parent | 1482471d19e77d794012dbacaa65c44ceaae37bb (diff) | |
[POWERPC] Add arch-specific walk_memory_remove() for 64-bit powerpc
walk_memory_resource() verifies if there are holes in a given memory
range, by checking against /proc/iomem. On x86/ia64 system memory is
represented in /proc/iomem. On powerpc, we don't show system memory as
IO resource in /proc/iomem - instead it's maintained in
/proc/device-tree.
This provides a way for an architecture to provide its own
walk_memory_resource() function. On powerpc, the memory region is
small (16MB), contiguous and non-overlapping. So extra checking
against the device-tree is not needed.
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Kumar Gala <galak@gate.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/Kconfig | 3 | ||||
| -rw-r--r-- | arch/powerpc/mm/mem.c | 17 |
2 files changed, 20 insertions, 0 deletions
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index d55063c021d..26b963c33c8 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -272,6 +272,9 @@ config HOTPLUG_CPU config ARCH_ENABLE_MEMORY_HOTPLUG def_bool y +config ARCH_HAS_WALK_MEMORY + def_bool y + config ARCH_ENABLE_MEMORY_HOTREMOVE def_bool y diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index f0a1fd268b7..be5c506779a 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -145,6 +145,23 @@ out: return ret; } #endif /* CONFIG_MEMORY_HOTREMOVE */ + +/* + * walk_memory_resource() needs to make sure there is no holes in a given + * memory range. On PPC64, since this range comes from /sysfs, the range + * is guaranteed to be valid, non-overlapping and can not contain any + * holes. By the time we get here (memory add or remove), /proc/device-tree + * is updated and correct. Only reason we need to check against device-tree + * would be if we allow user-land to specify a memory range through a + * system call/ioctl etc. instead of doing offline/online through /sysfs. + */ +int +walk_memory_resource(unsigned long start_pfn, unsigned long nr_pages, void *arg, + int (*func)(unsigned long, unsigned long, void *)) +{ + return (*func)(start_pfn, nr_pages, arg); +} + #endif /* CONFIG_MEMORY_HOTPLUG */ void show_mem(void) |