mirror of https://gitee.com/openkylin/linux.git
156 lines
3.8 KiB
C
156 lines
3.8 KiB
C
/*
|
|
* 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);
|
|
|