1 files changed, 152 insertions, 0 deletions

diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c
new file mode 100644
index 000000000000..736df3cbbc55
--- /dev/null
+++ b/arch/powerpc/kvm/book3s_hv_builtin.c
@@ -0,0 +1,152 @@
+/*
+ * Copyright 2011 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kvm_host.h>
+#include <linux/preempt.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/bootmem.h>
+#include <linux/init.h>
+
+#include <asm/cputable.h>
+#include <asm/kvm_ppc.h>
+#include <asm/kvm_book3s.h>
+
+/*
+ * This maintains a list of RMAs (real mode areas) for KVM guests to use.
+ * Each RMA has to be physically contiguous and of a size that the
+ * hardware supports.  PPC970 and POWER7 support 64MB, 128MB and 256MB,
+ * and other larger sizes.  Since we are unlikely to be allocate that
+ * much physically contiguous memory after the system is up and running,
+ * we preallocate a set of RMAs in early boot for KVM to use.
+ */
+static unsigned long kvm_rma_size = 64 << 20;   /* 64MB */
+static unsigned long kvm_rma_count;
+
+static int __init early_parse_rma_size(char *p)
+{
+        if (!p)
+                return 1;
+
+        kvm_rma_size = memparse(p, &p);
+
+        return 0;
+}
+early_param("kvm_rma_size", early_parse_rma_size);
+
+static int __init early_parse_rma_count(char *p)
+{
+        if (!p)
+                return 1;
+
+        kvm_rma_count = simple_strtoul(p, NULL, 0);
+
+        return 0;
+}
+early_param("kvm_rma_count", early_parse_rma_count);
+
+static struct kvmppc_rma_info *rma_info;
+static LIST_HEAD(free_rmas);
+static DEFINE_SPINLOCK(rma_lock);
+
+/* Work out RMLS (real mode limit selector) field value for a given RMA size.
+   Assumes POWER7. */
+static inline int lpcr_rmls(unsigned long rma_size)
+{
+        switch (rma_size) {
+        case 32ul << 20:        /* 32 MB */
+                return 8;
+        case 64ul << 20:        /* 64 MB */
+                return 3;
+        case 128ul << 20:       /* 128 MB */
+                return 7;
+        case 256ul << 20:       /* 256 MB */
+                return 4;
+        case 1ul << 30:         /* 1 GB */
+                return 2;
+        case 16ul << 30:        /* 16 GB */
+                return 1;
+        case 256ul << 30:       /* 256 GB */
+                return 0;
+        default:
+                return -1;
+        }
+}
+
+/*
+ * Called at boot time while the bootmem allocator is active,
+ * to allocate contiguous physical memory for the real memory
+ * areas for guests.
+ */
+void kvm_rma_init(void)
+{
+        unsigned long i;
+        unsigned long j, npages;
+        void *rma;
+        struct page *pg;
+
+        /* Only do this on POWER7 in HV mode */
+        if (!cpu_has_feature(CPU_FTR_HVMODE_206))
+                return;
+
+        if (!kvm_rma_size || !kvm_rma_count)
+                return;
+
+        /* Check that the requested size is one supported in hardware */
+        if (lpcr_rmls(kvm_rma_size) < 0) {
+                pr_err("RMA size of 0x%lx not supported\n", kvm_rma_size);
+                return;
+        }
+
+        npages = kvm_rma_size >> PAGE_SHIFT;
+        rma_info = alloc_bootmem(kvm_rma_count * sizeof(struct kvmppc_rma_info));
+        for (i = 0; i < kvm_rma_count; ++i) {
+                rma = alloc_bootmem_align(kvm_rma_size, kvm_rma_size);
+                pr_info("Allocated KVM RMA at %p (%ld MB)\n", rma,
+                        kvm_rma_size >> 20);
+                rma_info[i].base_virt = rma;
+                rma_info[i].base_pfn = __pa(rma) >> PAGE_SHIFT;
+                rma_info[i].npages = npages;
+                list_add_tail(&rma_info[i].list, &free_rmas);
+                atomic_set(&rma_info[i].use_count, 0);
+
+                pg = pfn_to_page(rma_info[i].base_pfn);
+                for (j = 0; j < npages; ++j) {
+                        atomic_inc(&pg->_count);
+                        ++pg;
+                }
+        }
+}
+
+struct kvmppc_rma_info *kvm_alloc_rma(void)
+{
+        struct kvmppc_rma_info *ri;
+
+        ri = NULL;
+        spin_lock(&rma_lock);
+        if (!list_empty(&free_rmas)) {
+                ri = list_first_entry(&free_rmas, struct kvmppc_rma_info, list);
+                list_del(&ri->list);
+                atomic_inc(&ri->use_count);
+        }
+        spin_unlock(&rma_lock);
+        return ri;
+}
+EXPORT_SYMBOL_GPL(kvm_alloc_rma);
+
+void kvm_release_rma(struct kvmppc_rma_info *ri)
+{
+        if (atomic_dec_and_test(&ri->use_count)) {
+                spin_lock(&rma_lock);
+                list_add_tail(&ri->list, &free_rmas);
+                spin_unlock(&rma_lock);
+
+        }
+}
+EXPORT_SYMBOL_GPL(kvm_release_rma);
+