[mirror_ubuntu-bionic-kernel.git] / arch / powerpc / kvm / book3s_hv_builtin.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/export.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>

#define KVM_LINEAR_RMA		0

static void __init kvm_linear_init_one(ulong size, int count, int type);
static struct kvmppc_linear_info *kvm_alloc_linear(int type);
static void kvm_release_linear(struct kvmppc_linear_info *ri);

/*************** RMA *************/

/*
 * 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;

/* 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;
	}
}

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);

struct kvmppc_linear_info *kvm_alloc_rma(void)
{
	return kvm_alloc_linear(KVM_LINEAR_RMA);
}
EXPORT_SYMBOL_GPL(kvm_alloc_rma);

void kvm_release_rma(struct kvmppc_linear_info *ri)
{
	kvm_release_linear(ri);
}
EXPORT_SYMBOL_GPL(kvm_release_rma);

/*************** generic *************/

static LIST_HEAD(free_linears);
static DEFINE_SPINLOCK(linear_lock);

static void __init kvm_linear_init_one(ulong size, int count, int type)
{
	unsigned long i;
	unsigned long j, npages;
	void *linear;
	struct page *pg;
	const char *typestr;
	struct kvmppc_linear_info *linear_info;

	if (!count)
		return;

	typestr = (type == KVM_LINEAR_RMA) ? "RMA" : "";

	npages = size >> PAGE_SHIFT;
	linear_info = alloc_bootmem(count * sizeof(struct kvmppc_linear_info));
	for (i = 0; i < count; ++i) {
		linear = alloc_bootmem_align(size, size);
		pr_info("Allocated KVM %s at %p (%ld MB)\n", typestr, linear,
			size >> 20);
		linear_info[i].base_virt = linear;
		linear_info[i].base_pfn = __pa(linear) >> PAGE_SHIFT;
		linear_info[i].npages = npages;
		linear_info[i].type = type;
		list_add_tail(&linear_info[i].list, &free_linears);
		atomic_set(&linear_info[i].use_count, 0);

		pg = pfn_to_page(linear_info[i].base_pfn);
		for (j = 0; j < npages; ++j) {
			atomic_inc(&pg->_count);
			++pg;
		}
	}
}

static struct kvmppc_linear_info *kvm_alloc_linear(int type)
{
	struct kvmppc_linear_info *ri;

	ri = NULL;
	spin_lock(&linear_lock);
	list_for_each_entry(ri, &free_linears, list) {
		if (ri->type != type)
			continue;

		list_del(&ri->list);
		atomic_inc(&ri->use_count);
		break;
	}
	spin_unlock(&linear_lock);
	memset(ri->base_virt, 0, ri->npages << PAGE_SHIFT);
	return ri;
}

static void kvm_release_linear(struct kvmppc_linear_info *ri)
{
	if (atomic_dec_and_test(&ri->use_count)) {
		spin_lock(&linear_lock);
		list_add_tail(&ri->list, &free_linears);
		spin_unlock(&linear_lock);

	}
}

/*
 * Called at boot time while the bootmem allocator is active,
 * to allocate contiguous physical memory for the hash page
 * tables for guests.
 */
void __init kvm_linear_init(void)
{
	/* RMA */
	/* 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;
	}

	kvm_linear_init_one(kvm_rma_size, kvm_rma_count, KVM_LINEAR_RMA);
}
Commit	Line	Data
aa04b4cc PM	1	/*
	2	* Copyright 2011 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License, version 2, as
	6	* published by the Free Software Foundation.
	7	*/
	8
	9	#include <linux/kvm_host.h>
	10	#include <linux/preempt.h>
66b15db6	11	#include <linux/export.h>
aa04b4cc PM	12	#include <linux/sched.h>
	13	#include <linux/spinlock.h>
	14	#include <linux/bootmem.h>
	15	#include <linux/init.h>
	16
	17	#include <asm/cputable.h>
	18	#include <asm/kvm_ppc.h>
	19	#include <asm/kvm_book3s.h>
	20
b4e70611 AG	21	#define KVM_LINEAR_RMA 0
	22
	23	static void __init kvm_linear_init_one(ulong size, int count, int type);
	24	static struct kvmppc_linear_info *kvm_alloc_linear(int type);
	25	static void kvm_release_linear(struct kvmppc_linear_info *ri);
	26
	27	/************* RMA ***********/
	28
aa04b4cc PM	29	/*
	30	* This maintains a list of RMAs (real mode areas) for KVM guests to use.
	31	* Each RMA has to be physically contiguous and of a size that the
	32	* hardware supports. PPC970 and POWER7 support 64MB, 128MB and 256MB,
	33	* and other larger sizes. Since we are unlikely to be allocate that
	34	* much physically contiguous memory after the system is up and running,
	35	* we preallocate a set of RMAs in early boot for KVM to use.
	36	*/
	37	static unsigned long kvm_rma_size = 64 << 20; /* 64MB */
	38	static unsigned long kvm_rma_count;
	39
aa04b4cc	40	/* Work out RMLS (real mode limit selector) field value for a given RMA size.
9e368f29	41	Assumes POWER7 or PPC970. */
aa04b4cc PM	42	static inline int lpcr_rmls(unsigned long rma_size)
	43	{
	44	switch (rma_size) {
	45	case 32ul << 20: /* 32 MB */
9e368f29 PM	46	if (cpu_has_feature(CPU_FTR_ARCH_206))
	47	return 8; /* only supported on POWER7 */
	48	return -1;
aa04b4cc PM	49	case 64ul << 20: /* 64 MB */
	50	return 3;
	51	case 128ul << 20: /* 128 MB */
	52	return 7;
	53	case 256ul << 20: /* 256 MB */
	54	return 4;
	55	case 1ul << 30: /* 1 GB */
	56	return 2;
	57	case 16ul << 30: /* 16 GB */
	58	return 1;
	59	case 256ul << 30: /* 256 GB */
	60	return 0;
	61	default:
	62	return -1;
	63	}
	64	}
	65
b4e70611 AG	66	static int __init early_parse_rma_size(char *p)
	67	{
	68	if (!p)
	69	return 1;
	70
	71	kvm_rma_size = memparse(p, &p);
	72
	73	return 0;
	74	}
	75	early_param("kvm_rma_size", early_parse_rma_size);
	76
	77	static int __init early_parse_rma_count(char *p)
	78	{
	79	if (!p)
	80	return 1;
	81
	82	kvm_rma_count = simple_strtoul(p, NULL, 0);
	83
	84	return 0;
	85	}
	86	early_param("kvm_rma_count", early_parse_rma_count);
	87
	88	struct kvmppc_linear_info *kvm_alloc_rma(void)
	89	{
	90	return kvm_alloc_linear(KVM_LINEAR_RMA);
	91	}
	92	EXPORT_SYMBOL_GPL(kvm_alloc_rma);
	93
	94	void kvm_release_rma(struct kvmppc_linear_info *ri)
	95	{
	96	kvm_release_linear(ri);
	97	}
	98	EXPORT_SYMBOL_GPL(kvm_release_rma);
	99
	100	/************* generic ***********/
	101
	102	static LIST_HEAD(free_linears);
	103	static DEFINE_SPINLOCK(linear_lock);
	104
	105	static void __init kvm_linear_init_one(ulong size, int count, int type)
aa04b4cc PM	106	{
	107	unsigned long i;
	108	unsigned long j, npages;
b4e70611	109	void *linear;
aa04b4cc	110	struct page *pg;
b4e70611 AG	111	const char *typestr;
b4e70611 AG	112	struct kvmppc_linear_info *linear_info;
aa04b4cc	113
b4e70611	114	if (!count)
aa04b4cc PM	115	return;
aa04b4cc PM	116
b4e70611 AG	117	typestr = (type == KVM_LINEAR_RMA) ? "RMA" : "";
	118
	119	npages = size >> PAGE_SHIFT;
	120	linear_info = alloc_bootmem(count * sizeof(struct kvmppc_linear_info));
	121	for (i = 0; i < count; ++i) {
	122	linear = alloc_bootmem_align(size, size);
	123	pr_info("Allocated KVM %s at %p (%ld MB)\n", typestr, linear,
	124	size >> 20);
	125	linear_info[i].base_virt = linear;
	126	linear_info[i].base_pfn = __pa(linear) >> PAGE_SHIFT;
	127	linear_info[i].npages = npages;
	128	linear_info[i].type = type;
	129	list_add_tail(&linear_info[i].list, &free_linears);
	130	atomic_set(&linear_info[i].use_count, 0);
	131
	132	pg = pfn_to_page(linear_info[i].base_pfn);
aa04b4cc PM	133	for (j = 0; j < npages; ++j) {
	134	atomic_inc(&pg->_count);
	135	++pg;
	136	}
	137	}
	138	}
	139
b4e70611	140	static struct kvmppc_linear_info *kvm_alloc_linear(int type)
aa04b4cc	141	{
b4e70611	142	struct kvmppc_linear_info *ri;
aa04b4cc PM	143
aa04b4cc PM	144	ri = NULL;
b4e70611 AG	145	spin_lock(&linear_lock);
	146	list_for_each_entry(ri, &free_linears, list) {
	147	if (ri->type != type)
	148	continue;
	149
aa04b4cc PM	150	list_del(&ri->list);
aa04b4cc PM	151	atomic_inc(&ri->use_count);
b4e70611	152	break;
aa04b4cc	153	}
b4e70611	154	spin_unlock(&linear_lock);
b7f5d011	155	memset(ri->base_virt, 0, ri->npages << PAGE_SHIFT);
aa04b4cc PM	156	return ri;
aa04b4cc PM	157	}
aa04b4cc	158
b4e70611	159	static void kvm_release_linear(struct kvmppc_linear_info *ri)
aa04b4cc PM	160	{
aa04b4cc PM	161	if (atomic_dec_and_test(&ri->use_count)) {
b4e70611 AG	162	spin_lock(&linear_lock);
	163	list_add_tail(&ri->list, &free_linears);
	164	spin_unlock(&linear_lock);
aa04b4cc PM	165
	166	}
	167	}
aa04b4cc	168
b4e70611 AG	169	/*
	170	* Called at boot time while the bootmem allocator is active,
	171	* to allocate contiguous physical memory for the hash page
	172	* tables for guests.
	173	*/
	174	void __init kvm_linear_init(void)
	175	{
	176	/* RMA */
	177	/* Only do this on PPC970 in HV mode */
	178	if (!cpu_has_feature(CPU_FTR_HVMODE) \|\|
	179	!cpu_has_feature(CPU_FTR_ARCH_201))
	180	return;
	181
	182	if (!kvm_rma_size \|\| !kvm_rma_count)
	183	return;
	184
	185	/* Check that the requested size is one supported in hardware */
	186	if (lpcr_rmls(kvm_rma_size) < 0) {
	187	pr_err("RMA size of 0x%lx not supported\n", kvm_rma_size);
	188	return;
	189	}
	190
	191	kvm_linear_init_one(kvm_rma_size, kvm_rma_count, KVM_LINEAR_RMA);
	192	}