From 3f861315e76a366c19ed273e4c38beda28e287a6 Mon Sep 17 00:00:00 2001
From: Tejun Heo <tj@kernel.org>
Date: Fri, 18 Jun 2010 11:44:31 +0200
Subject: [PATCH] --- yaml --- r: 200563 b: refs/heads/master c:
 9983b6f0cf8263e51bcf4c8a9dc0c1ef175b3c60 h: refs/heads/master i:   200561:
 84dc5586c40e8dbd83b2de891ecaabee970ee22d   200559:
 f916c812ea3b20e2b4da793f49500e3c798dddbb v: v3

---
 [refs]            |  2 +-
 trunk/mm/percpu.c | 31 ++++++++++++++++++++++++++++---
 2 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/[refs] b/[refs]
index 43aa3f34a242..6106309581c5 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: a92d3ff9e5dbd958d8008a3e7a573e988e370ca3
+refs/heads/master: 9983b6f0cf8263e51bcf4c8a9dc0c1ef175b3c60
diff --git a/trunk/mm/percpu.c b/trunk/mm/percpu.c
index 46485e1b26fc..6470e7710231 100644
--- a/trunk/mm/percpu.c
+++ b/trunk/mm/percpu.c
@@ -229,8 +229,8 @@ static int __maybe_unused pcpu_page_idx(unsigned int cpu, int page_idx)
 	return pcpu_unit_map[cpu] * pcpu_unit_pages + page_idx;
 }
 
-static unsigned long __maybe_unused pcpu_chunk_addr(struct pcpu_chunk *chunk,
-						unsigned int cpu, int page_idx)
+static unsigned long pcpu_chunk_addr(struct pcpu_chunk *chunk,
+				     unsigned int cpu, int page_idx)
 {
 	return (unsigned long)chunk->base_addr + pcpu_unit_offsets[cpu] +
 		(page_idx << PAGE_SHIFT);
@@ -978,7 +978,32 @@ bool is_kernel_percpu_address(unsigned long addr)
  */
 phys_addr_t per_cpu_ptr_to_phys(void *addr)
 {
-	if (pcpu_addr_in_first_chunk(addr)) {
+	void __percpu *base = __addr_to_pcpu_ptr(pcpu_base_addr);
+	bool in_first_chunk = false;
+	unsigned long first_start, first_end;
+	unsigned int cpu;
+
+	/*
+	 * The following test on first_start/end isn't strictly
+	 * necessary but will speed up lookups of addresses which
+	 * aren't in the first chunk.
+	 */
+	first_start = pcpu_chunk_addr(pcpu_first_chunk, pcpu_first_unit_cpu, 0);
+	first_end = pcpu_chunk_addr(pcpu_first_chunk, pcpu_last_unit_cpu,
+				    pcpu_unit_pages);
+	if ((unsigned long)addr >= first_start &&
+	    (unsigned long)addr < first_end) {
+		for_each_possible_cpu(cpu) {
+			void *start = per_cpu_ptr(base, cpu);
+
+			if (addr >= start && addr < start + pcpu_unit_size) {
+				in_first_chunk = true;
+				break;
+			}
+		}
+	}
+
+	if (in_first_chunk) {
 		if ((unsigned long)addr < VMALLOC_START ||
 		    (unsigned long)addr >= VMALLOC_END)
 			return __pa(addr);