memblock, nobootmem: add memblock_virt_alloc_low()

The new memblock_virt APIs are used to replaced old bootmem API.

We need to allocate page below 4G for swiotlb.

That should fix regression on Andrew's system that is using swiotlb.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 40 insertions, 3 deletions

diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 1e8b030dbefd..b0df9761de6d 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -731,7 +731,7 @@ static void __init request_standard_resources(const struct machine_desc *mdesc)
         kernel_data.end     = virt_to_phys(_end - 1);
 
         for_each_memblock(memory, region) {
-                res = memblock_virt_alloc(sizeof(*res), 0);
+                res = memblock_virt_alloc_low(sizeof(*res), 0);
                 res->name  = "System RAM";
                 res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
                 res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
diff --git a/include/linux/bootmem.h b/include/linux/bootmem.h
index 2fae55def608..b388223bd4a9 100644
--- a/include/linux/bootmem.h
+++ b/include/linux/bootmem.h
@@ -175,6 +175,27 @@ static inline void * __init memblock_virt_alloc_nopanic(
                                                     NUMA_NO_NODE);
 }
 
+#ifndef ARCH_LOW_ADDRESS_LIMIT
+#define ARCH_LOW_ADDRESS_LIMIT  0xffffffffUL
+#endif
+
+static inline void * __init memblock_virt_alloc_low(
+                                        phys_addr_t size, phys_addr_t align)
+{
+        return memblock_virt_alloc_try_nid(size, align,
+                                                   BOOTMEM_LOW_LIMIT,
+                                                   ARCH_LOW_ADDRESS_LIMIT,
+                                                   NUMA_NO_NODE);
+}
+static inline void * __init memblock_virt_alloc_low_nopanic(
+                                        phys_addr_t size, phys_addr_t align)
+{
+        return memblock_virt_alloc_try_nid_nopanic(size, align,
+                                                   BOOTMEM_LOW_LIMIT,
+                                                   ARCH_LOW_ADDRESS_LIMIT,
+                                                   NUMA_NO_NODE);
+}
+
 static inline void * __init memblock_virt_alloc_from_nopanic(
                 phys_addr_t size, phys_addr_t align, phys_addr_t min_addr)
 {
@@ -238,6 +259,22 @@ static inline void * __init memblock_virt_alloc_nopanic(
         return __alloc_bootmem_nopanic(size, align, BOOTMEM_LOW_LIMIT);
 }
 
+static inline void * __init memblock_virt_alloc_low(
+                                        phys_addr_t size, phys_addr_t align)
+{
+        if (!align)
+                align = SMP_CACHE_BYTES;
+        return __alloc_bootmem_low(size, align, BOOTMEM_LOW_LIMIT);
+}
+
+static inline void * __init memblock_virt_alloc_low_nopanic(
+                                        phys_addr_t size, phys_addr_t align)
+{
+        if (!align)
+                align = SMP_CACHE_BYTES;
+        return __alloc_bootmem_low_nopanic(size, align, BOOTMEM_LOW_LIMIT);
+}
+
 static inline void * __init memblock_virt_alloc_from_nopanic(
                 phys_addr_t size, phys_addr_t align, phys_addr_t min_addr)
 {
diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index 2e1c102759ce..b604b831f4d1 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -172,7 +172,7 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
         /*
          * Get the overflow emergency buffer
          */
-        v_overflow_buffer = memblock_virt_alloc_nopanic(
+        v_overflow_buffer = memblock_virt_alloc_low_nopanic(
                                                 PAGE_ALIGN(io_tlb_overflow),
                                                 PAGE_SIZE);
         if (!v_overflow_buffer)
@@ -220,7 +220,7 @@ swiotlb_init(int verbose)
         bytes = io_tlb_nslabs << IO_TLB_SHIFT;
 
         /* Get IO TLB memory from the low pages */
-        vstart = memblock_virt_alloc_nopanic(PAGE_ALIGN(bytes), PAGE_SIZE);
+        vstart = memblock_virt_alloc_low_nopanic(PAGE_ALIGN(bytes), PAGE_SIZE);
         if (vstart && !swiotlb_init_with_tbl(vstart, io_tlb_nslabs, verbose))
                 return;