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Diffstat (limited to 'arch/powerpc/kvm/book3s_hv_builtin.c')
-rw-r--r--arch/powerpc/kvm/book3s_hv_builtin.c155
1 files changed, 155 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..d43120355eec
--- /dev/null
+++ b/arch/powerpc/kvm/book3s_hv_builtin.c
@@ -0,0 +1,155 @@
+/*
+ * 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 or PPC970. */
+static inline int lpcr_rmls(unsigned long rma_size)
+{
+ switch (rma_size) {
+ case 32ul << 20: /* 32 MB */
+ if (cpu_has_feature(CPU_FTR_ARCH_206))
+ return 8; /* only supported on POWER7 */
+ return -1;
+ 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 PPC970 in HV mode */
+ if (!cpu_has_feature(CPU_FTR_HVMODE) ||
+ !cpu_has_feature(CPU_FTR_ARCH_201))
+ 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);
+