Re: [RFC 1/7] powerpc/mm: Make vmemmap_populate accommodate ZONE_DEVICE memory

On 05/03/2016 01:34 PM, Balbir Singh wrote:

On 03/05/16 16:29, Anshuman Khandual wrote:

quoted

Change the vmemmap_populate function to detect device memory through
to_vmemmap_altmap and then call generic the __vmmemap_alloc_block_buf
function instead of vmemmap_alloc_block as the earlier can allocate
physical memory from the device range instead of the system RAM.

Signed-off-by: Anshuman Khandual <redacted>
---
 arch/powerpc/mm/init_64.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
index ba65566..db73708 100644
--- a/arch/powerpc/mm/init_64.c
+++ b/arch/powerpc/mm/init_64.c

@@ -42,6 +42,7 @@
 #include <linux/memblock.h>
 #include <linux/hugetlb.h>
 #include <linux/slab.h>
+#include <linux/memremap.h>
 
 #include <asm/pgalloc.h>
 #include <asm/page.h>

@@ -312,6 +313,7 @@ static __meminit void vmemmap_list_populate(unsigned long phys,
 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
 {
 	unsigned long page_size = 1 << mmu_psize_defs[mmu_vmemmap_psize].shift;
+	unsigned long orig = start;

I would much rather do struct vmem_altmap *altmap = to_vmem_altmap(start);

Sure, makes sense.