diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/mm/mem.c | 30 |
1 files changed, 23 insertions, 7 deletions
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index d9e37f365b5..f67e118116f 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -154,19 +154,35 @@ out: /* * 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. + * memory range. PPC64 does not maintain the memory layout in /proc/iomem. + * Instead it maintains it in lmb.memory structures. Walk through the + * memory regions, find holes and callback for contiguous regions. */ 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); + struct lmb_property res; + unsigned long pfn, len; + u64 end; + int ret = -1; + + res.base = (u64) start_pfn << PAGE_SHIFT; + res.size = (u64) nr_pages << PAGE_SHIFT; + + end = res.base + res.size - 1; + while ((res.base < end) && (lmb_find(&res) >= 0)) { + pfn = (unsigned long)(res.base >> PAGE_SHIFT); + len = (unsigned long)(res.size >> PAGE_SHIFT); + ret = (*func)(pfn, len, arg); + if (ret) + break; + res.base += (res.size + 1); + res.size = (end - res.base + 1); + } + return ret; } +EXPORT_SYMBOL_GPL(walk_memory_resource); #endif /* CONFIG_MEMORY_HOTPLUG */ |