1 files changed, 68 insertions, 2 deletions

diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c
index a4e72159234f..ebf9846f3c3b 100644
--- a/arch/powerpc/kernel/paca.c
+++ b/arch/powerpc/kernel/paca.c
@@ -27,6 +27,20 @@ extern unsigned long __toc_start;
 #ifdef CONFIG_PPC_BOOK3S
 
 /*
+ * We only have to have statically allocated lppaca structs on
+ * legacy iSeries, which supports at most 64 cpus.
+ */
+#ifdef CONFIG_PPC_ISERIES
+#if NR_CPUS < 64
+#define NR_LPPACAS      NR_CPUS
+#else
+#define NR_LPPACAS      64
+#endif
+#else /* not iSeries */
+#define NR_LPPACAS      1
+#endif
+
+/*
  * The structure which the hypervisor knows about - this structure
  * should not cross a page boundary.  The vpa_init/register_vpa call
  * is now known to fail if the lppaca structure crosses a page
@@ -36,7 +50,7 @@ extern unsigned long __toc_start;
  * will suffice to ensure that it doesn't cross a page boundary.
  */
 struct lppaca lppaca[] = {
-        [0 ... (NR_CPUS-1)] = {
+        [0 ... (NR_LPPACAS-1)] = {
                 .desc = 0xd397d781,     /* "LpPa" */
                 .size = sizeof(struct lppaca),
                 .dyn_proc_status = 2,
@@ -49,6 +63,54 @@ struct lppaca lppaca[] = {
         },
 };
 
+static struct lppaca *extra_lppacas;
+static long __initdata lppaca_size;
+
+static void allocate_lppacas(int nr_cpus, unsigned long limit)
+{
+        if (nr_cpus <= NR_LPPACAS)
+                return;
+
+        lppaca_size = PAGE_ALIGN(sizeof(struct lppaca) *
+                                 (nr_cpus - NR_LPPACAS));
+        extra_lppacas = __va(memblock_alloc_base(lppaca_size,
+                                                 PAGE_SIZE, limit));
+}
+
+static struct lppaca *new_lppaca(int cpu)
+{
+        struct lppaca *lp;
+
+        if (cpu < NR_LPPACAS)
+                return &lppaca[cpu];
+
+        lp = extra_lppacas + (cpu - NR_LPPACAS);
+        *lp = lppaca[0];
+
+        return lp;
+}
+
+static void free_lppacas(void)
+{
+        long new_size = 0, nr;
+
+        if (!lppaca_size)
+                return;
+        nr = num_possible_cpus() - NR_LPPACAS;
+        if (nr > 0)
+                new_size = PAGE_ALIGN(nr * sizeof(struct lppaca));
+        if (new_size >= lppaca_size)
+                return;
+
+        memblock_free(__pa(extra_lppacas) + new_size, lppaca_size - new_size);
+        lppaca_size = new_size;
+}
+
+#else
+
+static inline void allocate_lppacas(int nr_cpus, unsigned long limit) { }
+static inline void free_lppacas(void) { }
+
 #endif /* CONFIG_PPC_BOOK3S */
 
 #ifdef CONFIG_PPC_STD_MMU_64
@@ -88,7 +150,7 @@ void __init initialise_paca(struct paca_struct *new_paca, int cpu)
         unsigned long kernel_toc = (unsigned long)(&__toc_start) + 0x8000UL;
 
 #ifdef CONFIG_PPC_BOOK3S
-        new_paca->lppaca_ptr = &lppaca[cpu];
+        new_paca->lppaca_ptr = new_lppaca(cpu);
 #else
         new_paca->kernel_pgd = swapper_pg_dir;
 #endif
@@ -144,6 +206,8 @@ void __init allocate_pacas(void)
         printk(KERN_DEBUG "Allocated %u bytes for %d pacas at %p\n",
                 paca_size, nr_cpus, paca);
 
+        allocate_lppacas(nr_cpus, limit);
+
         /* Can't use for_each_*_cpu, as they aren't functional yet */
         for (cpu = 0; cpu < nr_cpus; cpu++)
                 initialise_paca(&paca[cpu], cpu);
@@ -164,4 +228,6 @@ void __init free_unused_pacas(void)
                 paca_size - new_size);
 
         paca_size = new_size;
+
+        free_lppacas();
 }