Memory hotplug operations require ranges aligned to memory block boundaries. This is a generic operation for hotplug.
Add memory_block_align_range() as a common helper in <linux/memory.h> that aligns the start address up and end address down to memory block boundaries. Update dax/kmem to use this helper. Signed-off-by: Gregory Price <[email protected]> --- drivers/dax/kmem.c | 4 +--- include/linux/memory.h | 22 ++++++++++++++++++++++ 2 files changed, 23 insertions(+), 3 deletions(-) diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c index eb693a581961..798f389df992 100644 --- a/drivers/dax/kmem.c +++ b/drivers/dax/kmem.c @@ -26,9 +26,7 @@ static int dax_kmem_range(struct dev_dax *dev_dax, int i, struct range *r) struct dev_dax_range *dax_range = &dev_dax->ranges[i]; struct range *range = &dax_range->range; - /* memory-block align the hotplug range */ - r->start = ALIGN(range->start, memory_block_size_bytes()); - r->end = ALIGN_DOWN(range->end + 1, memory_block_size_bytes()) - 1; + *r = memory_block_align_range(range); if (r->start >= r->end) { r->start = range->start; r->end = range->end; diff --git a/include/linux/memory.h b/include/linux/memory.h index 5bb5599c6b2b..17cdf6ba3823 100644 --- a/include/linux/memory.h +++ b/include/linux/memory.h @@ -20,6 +20,7 @@ #include <linux/compiler.h> #include <linux/mutex.h> #include <linux/memory_hotplug.h> +#include <linux/range.h> #define MIN_MEMORY_BLOCK_SIZE (1UL << SECTION_SIZE_BITS) @@ -100,6 +101,27 @@ int arch_get_memory_phys_device(unsigned long start_pfn); unsigned long memory_block_size_bytes(void); int set_memory_block_size_order(unsigned int order); +/** + * memory_block_align_range - align a physical address range to memory blocks + * @range: the input range to align + * + * Aligns the start address up and the end address down to memory block + * boundaries. This is required for memory hotplug operations which must + * operate on memory-block aligned ranges. + * + * Returns the aligned range. Callers should check that the returned + * range is valid (aligned.start < aligned.end) before using it. + */ +static inline struct range memory_block_align_range(const struct range *range) +{ + struct range aligned; + + aligned.start = ALIGN(range->start, memory_block_size_bytes()); + aligned.end = ALIGN_DOWN(range->end + 1, memory_block_size_bytes()) - 1; + + return aligned; +} + struct memory_notify { unsigned long start_pfn; unsigned long nr_pages; -- 2.53.0
