x86/numa: use get_pfn_range_for_nid to verify that node spans memory

Instead of looping over numa_meminfo array to detect node's start and
end addresses use get_pfn_range_for_init().

This is shorter and make it easier to lift numa_memblks to generic code.

Link: https://lkml.kernel.org/r/20240807064110.1003856-12-rppt@kernel.orgSigned-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Tested-by: Zi Yan <ziy@nvidia.com> # for x86_64 and arm64
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> [arm64 + CXL via QEMU]
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Rob Herring (Arm) <robh@kernel.org>
Cc: Samuel Holland <samuel.holland@sifive.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch/x86/mm/numa.c

@@ -521,17 +521,14 @@ static int __init numa_register_memblks(struct numa_meminfo *mi)
 
 	/* Finally register nodes. */
 	for_each_node_mask(nid, node_possible_map) {
-		u64 start = PFN_PHYS(max_pfn);
-		u64 end = 0;
+		unsigned long start_pfn, end_pfn;
 
-		for (i = 0; i < mi->nr_blks; i++) {
-			if (nid != mi->blk[i].nid)
-				continue;
-			start = min(mi->blk[i].start, start);
-			end = max(mi->blk[i].end, end);
-		}
-
-		if (start >= end)
+		/*
+		 * Note, get_pfn_range_for_nid() depends on
+		 * memblock_set_node() having already happened
+		 */
+		get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
+		if (start_pfn >= end_pfn)
 			continue;
 
 		alloc_node_data(nid);