[mirror_ubuntu-hirsute-kernel.git] / arch / arm / xen / p2m.c

#include <linux/memblock.h>
#include <linux/gfp.h>
#include <linux/export.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/dma-mapping.h>
#include <linux/vmalloc.h>
#include <linux/swiotlb.h>

#include <xen/xen.h>
#include <xen/interface/memory.h>
#include <xen/page.h>
#include <xen/swiotlb-xen.h>

#include <asm/cacheflush.h>
#include <asm/xen/hypercall.h>
#include <asm/xen/interface.h>

struct xen_p2m_entry {
	unsigned long pfn;
	unsigned long mfn;
	unsigned long nr_pages;
	struct rb_node rbnode_phys;
};

static rwlock_t p2m_lock;
struct rb_root phys_to_mach = RB_ROOT;
EXPORT_SYMBOL_GPL(phys_to_mach);

static int xen_add_phys_to_mach_entry(struct xen_p2m_entry *new)
{
	struct rb_node **link = &phys_to_mach.rb_node;
	struct rb_node *parent = NULL;
	struct xen_p2m_entry *entry;
	int rc = 0;

	while (*link) {
		parent = *link;
		entry = rb_entry(parent, struct xen_p2m_entry, rbnode_phys);

		if (new->pfn == entry->pfn)
			goto err_out;

		if (new->pfn < entry->pfn)
			link = &(*link)->rb_left;
		else
			link = &(*link)->rb_right;
	}
	rb_link_node(&new->rbnode_phys, parent, link);
	rb_insert_color(&new->rbnode_phys, &phys_to_mach);
	goto out;

err_out:
	rc = -EINVAL;
	pr_warn("%s: cannot add pfn=%pa -> mfn=%pa: pfn=%pa -> mfn=%pa already exists\n",
			__func__, &new->pfn, &new->mfn, &entry->pfn, &entry->mfn);
out:
	return rc;
}

unsigned long __pfn_to_mfn(unsigned long pfn)
{
	struct rb_node *n = phys_to_mach.rb_node;
	struct xen_p2m_entry *entry;
	unsigned long irqflags;

	read_lock_irqsave(&p2m_lock, irqflags);
	while (n) {
		entry = rb_entry(n, struct xen_p2m_entry, rbnode_phys);
		if (entry->pfn <= pfn &&
				entry->pfn + entry->nr_pages > pfn) {
			unsigned long mfn = entry->mfn + (pfn - entry->pfn);
			read_unlock_irqrestore(&p2m_lock, irqflags);
			return mfn;
		}
		if (pfn < entry->pfn)
			n = n->rb_left;
		else
			n = n->rb_right;
	}
	read_unlock_irqrestore(&p2m_lock, irqflags);

	return INVALID_P2M_ENTRY;
}
EXPORT_SYMBOL_GPL(__pfn_to_mfn);

int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops,
			    struct gnttab_map_grant_ref *kmap_ops,
			    struct page **pages, unsigned int count)
{
	int i;

	for (i = 0; i < count; i++) {
		if (map_ops[i].status)
			continue;
		set_phys_to_machine(map_ops[i].host_addr >> XEN_PAGE_SHIFT,
				    map_ops[i].dev_bus_addr >> XEN_PAGE_SHIFT);
	}

	return 0;
}
EXPORT_SYMBOL_GPL(set_foreign_p2m_mapping);

int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops,
			      struct gnttab_unmap_grant_ref *kunmap_ops,
			      struct page **pages, unsigned int count)
{
	int i;

	for (i = 0; i < count; i++) {
		set_phys_to_machine(unmap_ops[i].host_addr >> XEN_PAGE_SHIFT,
				    INVALID_P2M_ENTRY);
	}

	return 0;
}
EXPORT_SYMBOL_GPL(clear_foreign_p2m_mapping);

bool __set_phys_to_machine_multi(unsigned long pfn,
		unsigned long mfn, unsigned long nr_pages)
{
	int rc;
	unsigned long irqflags;
	struct xen_p2m_entry *p2m_entry;
	struct rb_node *n = phys_to_mach.rb_node;

	if (mfn == INVALID_P2M_ENTRY) {
		write_lock_irqsave(&p2m_lock, irqflags);
		while (n) {
			p2m_entry = rb_entry(n, struct xen_p2m_entry, rbnode_phys);
			if (p2m_entry->pfn <= pfn &&
					p2m_entry->pfn + p2m_entry->nr_pages > pfn) {
				rb_erase(&p2m_entry->rbnode_phys, &phys_to_mach);
				write_unlock_irqrestore(&p2m_lock, irqflags);
				kfree(p2m_entry);
				return true;
			}
			if (pfn < p2m_entry->pfn)
				n = n->rb_left;
			else
				n = n->rb_right;
		}
		write_unlock_irqrestore(&p2m_lock, irqflags);
		return true;
	}

	p2m_entry = kzalloc(sizeof(*p2m_entry), GFP_NOWAIT);
	if (!p2m_entry)
		return false;

	p2m_entry->pfn = pfn;
	p2m_entry->nr_pages = nr_pages;
	p2m_entry->mfn = mfn;

	write_lock_irqsave(&p2m_lock, irqflags);
	rc = xen_add_phys_to_mach_entry(p2m_entry);
	if (rc < 0) {
		write_unlock_irqrestore(&p2m_lock, irqflags);
		kfree(p2m_entry);
		return false;
	}
	write_unlock_irqrestore(&p2m_lock, irqflags);
	return true;
}
EXPORT_SYMBOL_GPL(__set_phys_to_machine_multi);

bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn)
{
	return __set_phys_to_machine_multi(pfn, mfn, 1);
}
EXPORT_SYMBOL_GPL(__set_phys_to_machine);

static int p2m_init(void)
{
	rwlock_init(&p2m_lock);
	return 0;
}
arch_initcall(p2m_init);
Commit	Line	Data
57c8a661	1	#include <linux/memblock.h>
4a19138c SS	2	#include <linux/gfp.h>
4a19138c SS	3	#include <linux/export.h>
a494ee6c	4	#include <linux/spinlock.h>
4a19138c SS	5	#include <linux/slab.h>
	6	#include <linux/types.h>
	7	#include <linux/dma-mapping.h>
	8	#include <linux/vmalloc.h>
	9	#include <linux/swiotlb.h>
	10
	11	#include <xen/xen.h>
	12	#include <xen/interface/memory.h>
a9fd60e2	13	#include <xen/page.h>
4a19138c SS	14	#include <xen/swiotlb-xen.h>
	15
	16	#include <asm/cacheflush.h>
4a19138c SS	17	#include <asm/xen/hypercall.h>
	18	#include <asm/xen/interface.h>
	19
	20	struct xen_p2m_entry {
	21	unsigned long pfn;
	22	unsigned long mfn;
	23	unsigned long nr_pages;
4a19138c SS	24	struct rb_node rbnode_phys;
	25	};
	26
f9c7ec16	27	static rwlock_t p2m_lock;
4a19138c	28	struct rb_root phys_to_mach = RB_ROOT;
c8999a88	29	EXPORT_SYMBOL_GPL(phys_to_mach);
4a19138c SS	30
	31	static int xen_add_phys_to_mach_entry(struct xen_p2m_entry *new)
	32	{
	33	struct rb_node **link = &phys_to_mach.rb_node;
	34	struct rb_node *parent = NULL;
	35	struct xen_p2m_entry *entry;
	36	int rc = 0;
	37
	38	while (*link) {
	39	parent = *link;
	40	entry = rb_entry(parent, struct xen_p2m_entry, rbnode_phys);
	41
4a19138c SS	42	if (new->pfn == entry->pfn)
	43	goto err_out;
	44
	45	if (new->pfn < entry->pfn)
	46	link = &(*link)->rb_left;
	47	else
	48	link = &(*link)->rb_right;
	49	}
	50	rb_link_node(&new->rbnode_phys, parent, link);
	51	rb_insert_color(&new->rbnode_phys, &phys_to_mach);
	52	goto out;
	53
	54	err_out:
	55	rc = -EINVAL;
	56	pr_warn("%s: cannot add pfn=%pa -> mfn=%pa: pfn=%pa -> mfn=%pa already exists\n",
	57	__func__, &new->pfn, &new->mfn, &entry->pfn, &entry->mfn);
	58	out:
	59	return rc;
	60	}
	61
	62	unsigned long __pfn_to_mfn(unsigned long pfn)
	63	{
	64	struct rb_node *n = phys_to_mach.rb_node;
	65	struct xen_p2m_entry *entry;
	66	unsigned long irqflags;
	67
	68	read_lock_irqsave(&p2m_lock, irqflags);
	69	while (n) {
	70	entry = rb_entry(n, struct xen_p2m_entry, rbnode_phys);
	71	if (entry->pfn <= pfn &&
	72	entry->pfn + entry->nr_pages > pfn) {
fe846979	73	unsigned long mfn = entry->mfn + (pfn - entry->pfn);
4a19138c	74	read_unlock_irqrestore(&p2m_lock, irqflags);
fe846979	75	return mfn;
4a19138c SS	76	}
	77	if (pfn < entry->pfn)
	78	n = n->rb_left;
	79	else
	80	n = n->rb_right;
	81	}
	82	read_unlock_irqrestore(&p2m_lock, irqflags);
	83
	84	return INVALID_P2M_ENTRY;
	85	}
	86	EXPORT_SYMBOL_GPL(__pfn_to_mfn);
	87
1429d46d ZK	88	int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops,
	89	struct gnttab_map_grant_ref *kmap_ops,
	90	struct page **pages, unsigned int count)
	91	{
	92	int i;
	93
	94	for (i = 0; i < count; i++) {
	95	if (map_ops[i].status)
	96	continue;
5ed5451d JG	97	set_phys_to_machine(map_ops[i].host_addr >> XEN_PAGE_SHIFT,
5ed5451d JG	98	map_ops[i].dev_bus_addr >> XEN_PAGE_SHIFT);
1429d46d ZK	99	}
	100
	101	return 0;
	102	}
	103	EXPORT_SYMBOL_GPL(set_foreign_p2m_mapping);
	104
	105	int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops,
853d0289	106	struct gnttab_unmap_grant_ref *kunmap_ops,
1429d46d ZK	107	struct page **pages, unsigned int count)
	108	{
	109	int i;
	110
	111	for (i = 0; i < count; i++) {
5ed5451d	112	set_phys_to_machine(unmap_ops[i].host_addr >> XEN_PAGE_SHIFT,
1429d46d ZK	113	INVALID_P2M_ENTRY);
	114	}
	115
	116	return 0;
	117	}
	118	EXPORT_SYMBOL_GPL(clear_foreign_p2m_mapping);
	119
4a19138c SS	120	bool __set_phys_to_machine_multi(unsigned long pfn,
	121	unsigned long mfn, unsigned long nr_pages)
	122	{
	123	int rc;
	124	unsigned long irqflags;
	125	struct xen_p2m_entry *p2m_entry;
	126	struct rb_node *n = phys_to_mach.rb_node;
	127
	128	if (mfn == INVALID_P2M_ENTRY) {
	129	write_lock_irqsave(&p2m_lock, irqflags);
	130	while (n) {
	131	p2m_entry = rb_entry(n, struct xen_p2m_entry, rbnode_phys);
	132	if (p2m_entry->pfn <= pfn &&
	133	p2m_entry->pfn + p2m_entry->nr_pages > pfn) {
4a19138c SS	134	rb_erase(&p2m_entry->rbnode_phys, &phys_to_mach);
4a19138c SS	135	write_unlock_irqrestore(&p2m_lock, irqflags);
e1d8f62a	136	kfree(p2m_entry);
4a19138c SS	137	return true;
	138	}
	139	if (pfn < p2m_entry->pfn)
	140	n = n->rb_left;
	141	else
	142	n = n->rb_right;
	143	}
	144	write_unlock_irqrestore(&p2m_lock, irqflags);
	145	return true;
	146	}
	147
031229b8	148	p2m_entry = kzalloc(sizeof(*p2m_entry), GFP_NOWAIT);
d6bb4ec3	149	if (!p2m_entry)
4a19138c	150	return false;
d6bb4ec3	151
4a19138c SS	152	p2m_entry->pfn = pfn;
	153	p2m_entry->nr_pages = nr_pages;
	154	p2m_entry->mfn = mfn;
	155
	156	write_lock_irqsave(&p2m_lock, irqflags);
84a0a967 ME	157	rc = xen_add_phys_to_mach_entry(p2m_entry);
84a0a967 ME	158	if (rc < 0) {
4a19138c	159	write_unlock_irqrestore(&p2m_lock, irqflags);
425f1cc2	160	kfree(p2m_entry);
4a19138c SS	161	return false;
	162	}
	163	write_unlock_irqrestore(&p2m_lock, irqflags);
	164	return true;
	165	}
	166	EXPORT_SYMBOL_GPL(__set_phys_to_machine_multi);
	167
	168	bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn)
	169	{
	170	return __set_phys_to_machine_multi(pfn, mfn, 1);
	171	}
	172	EXPORT_SYMBOL_GPL(__set_phys_to_machine);
	173
f9c7ec16	174	static int p2m_init(void)
4a19138c SS	175	{
	176	rwlock_init(&p2m_lock);
	177	return 0;
	178	}
	179	arch_initcall(p2m_init);