percpu: fix first chunk match in per_cpu_ptr_to_phys()

[net-next-2.6.git] / mm / percpu.c

diff --git a/mm/percpu.c b/mm/percpu.c
index 46485e1b26fccf4b609ad0b39c5353105fed66fb..6470e7710231a84d75dc793831bc9f92e178f8bb 100644 (file)
--- a/mm/percpu.c
+++ b/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);