Revert "MIPS: init: Ensure bootmem does not corrupt reserved memory"

This reverts commit 78d36a51aff258a26c4c2c12c4d86de0fae64e3a.

Signed-off-by: Sasha Levin <alexander.levin@verizon.com>

1 files changed, 3 insertions, 71 deletions

diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
index 51e77841f9f6..2734f6a4857d 100644
--- a/arch/mips/kernel/setup.c
+++ b/arch/mips/kernel/setup.c
@@ -147,35 +147,6 @@ void __init detect_memory_region(phys_addr_t start, phys_addr_t sz_min, phys_add
 	add_memory_region(start, size, BOOT_MEM_RAM);
 }
 
-bool __init memory_region_available(phys_addr_t start, phys_addr_t size)
-{
-	int i;
-	bool in_ram = false, free = true;
-
-	for (i = 0; i < boot_mem_map.nr_map; i++) {
-		phys_addr_t start_, end_;
-
-		start_ = boot_mem_map.map[i].addr;
-		end_ = boot_mem_map.map[i].addr + boot_mem_map.map[i].size;
-
-		switch (boot_mem_map.map[i].type) {
-		case BOOT_MEM_RAM:
-			if (start >= start_ && start + size <= end_)
-				in_ram = true;
-			break;
-		case BOOT_MEM_RESERVED:
-			if ((start >= start_ && start < end_) ||
-			    (start < start_ && start + size >= start_))
-				free = false;
-			break;
-		default:
-			continue;
-		}
-	}
-
-	return in_ram && free;
-}
-
 static void __init print_memory_map(void)
 {
 	int i;
@@ -324,19 +295,11 @@ static void __init bootmem_init(void)
 
 #else  /* !CONFIG_SGI_IP27 */
 
-static unsigned long __init bootmap_bytes(unsigned long pages)
-{
-	unsigned long bytes = DIV_ROUND_UP(pages, 8);
-
-	return ALIGN(bytes, sizeof(long));
-}
-
 static void __init bootmem_init(void)
 {
 	unsigned long reserved_end;
 	unsigned long mapstart = ~0UL;
 	unsigned long bootmap_size;
-	bool bootmap_valid = false;
 	int i;
 
 	/*
@@ -412,42 +375,11 @@ static void __init bootmem_init(void)
 #endif
 
 	/*
-	 * check that mapstart doesn't overlap with any of
-	 * memory regions that have been reserved through eg. DTB
-	 */
-	bootmap_size = bootmap_bytes(max_low_pfn - min_low_pfn);
-
-	bootmap_valid = memory_region_available(PFN_PHYS(mapstart),
-						bootmap_size);
-	for (i = 0; i < boot_mem_map.nr_map && !bootmap_valid; i++) {
-		unsigned long mapstart_addr;
-
-		switch (boot_mem_map.map[i].type) {
-		case BOOT_MEM_RESERVED:
-			mapstart_addr = PFN_ALIGN(boot_mem_map.map[i].addr +
-						boot_mem_map.map[i].size);
-			if (PHYS_PFN(mapstart_addr) < mapstart)
-				break;
-
-			bootmap_valid = memory_region_available(mapstart_addr,
-								bootmap_size);
-			if (bootmap_valid)
-				mapstart = PHYS_PFN(mapstart_addr);
-			break;
-		default:
-			break;
-		}
-	}
-
-	if (!bootmap_valid)
-		panic("No memory area to place a bootmap bitmap");
-
-	/*
 	 * Initialize the boot-time allocator with low memory only.
 	 */
-	if (bootmap_size != init_bootmem_node(NODE_DATA(0), mapstart,
-					 min_low_pfn, max_low_pfn))
-		panic("Unexpected memory size required for bootmap");
+	bootmap_size = init_bootmem_node(NODE_DATA(0), mapstart,
+					 min_low_pfn, max_low_pfn);
+
 
 	for (i = 0; i < boot_mem_map.nr_map; i++) {
 		unsigned long start, end;