[PATCH 01/15] KVM: PPC: Book3S HV: simplify kvm_cma_reserve()

From: Mike Rapoport
Date: Tue Jul 28 2020 - 01:12:26 EST


From: Mike Rapoport <rppt@xxxxxxxxxxxxx>

The memory size calculation in kvm_cma_reserve() traverses memblock.memory
rather than simply call memblock_phys_mem_size(). The comment in that
function suggests that at some point there should have been call to
memblock_analyze() before memblock_phys_mem_size() could be used.
As of now, there is no memblock_analyze() at all and
memblock_phys_mem_size() can be used as soon as cold-plug memory is
registerd with memblock.

Replace loop over memblock.memory with a call to memblock_phys_mem_size().

Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx>
---
arch/powerpc/kvm/book3s_hv_builtin.c | 11 ++---------
1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c
index 7cd3cf3d366b..56ab0d28de2a 100644
--- a/arch/powerpc/kvm/book3s_hv_builtin.c
+++ b/arch/powerpc/kvm/book3s_hv_builtin.c
@@ -95,22 +95,15 @@ EXPORT_SYMBOL_GPL(kvm_free_hpt_cma);
void __init kvm_cma_reserve(void)
{
unsigned long align_size;
- struct memblock_region *reg;
- phys_addr_t selected_size = 0;
+ phys_addr_t selected_size;

/*
* We need CMA reservation only when we are in HV mode
*/
if (!cpu_has_feature(CPU_FTR_HVMODE))
return;
- /*
- * We cannot use memblock_phys_mem_size() here, because
- * memblock_analyze() has not been called yet.
- */
- for_each_memblock(memory, reg)
- selected_size += memblock_region_memory_end_pfn(reg) -
- memblock_region_memory_base_pfn(reg);

+ selected_size = PHYS_PFN(memblock_phys_mem_size());
selected_size = (selected_size * kvm_cma_resv_ratio / 100) << PAGE_SHIFT;
if (selected_size) {
pr_debug("%s: reserving %ld MiB for global area\n", __func__,
--
2.26.2