1/*
2 * MMU operations common to all auto-translated physmap guests.
3 *
4 * Copyright (C) 2015 Citrix Systems R&D Ltd.
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License version 2
8 * as published by the Free Software Foundation; or, when distributed
9 * separately from the Linux kernel or incorporated into other
10 * software packages, subject to the following license:
11 *
12 * Permission is hereby granted, free of charge, to any person obtaining a copy
13 * of this source file (the "Software"), to deal in the Software without
14 * restriction, including without limitation the rights to use, copy, modify,
15 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
16 * and to permit persons to whom the Software is furnished to do so, subject to
17 * the following conditions:
18 *
19 * The above copyright notice and this permission notice shall be included in
20 * all copies or substantial portions of the Software.
21 *
22 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
23 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
24 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
25 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
26 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
27 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
28 * IN THE SOFTWARE.
29 */
30#include <linux/kernel.h>
31#include <linux/mm.h>
32
33#include <asm/xen/hypercall.h>
34#include <asm/xen/hypervisor.h>
35
36#include <xen/xen.h>
37#include <xen/page.h>
38#include <xen/interface/xen.h>
39#include <xen/interface/memory.h>
40
41/* map fgmfn of domid to lpfn in the current domain */
42static int map_foreign_page(unsigned long lpfn, unsigned long fgmfn,
43			    unsigned int domid)
44{
45	int rc;
46	struct xen_add_to_physmap_range xatp = {
47		.domid = DOMID_SELF,
48		.foreign_domid = domid,
49		.size = 1,
50		.space = XENMAPSPACE_gmfn_foreign,
51	};
52	xen_ulong_t idx = fgmfn;
53	xen_pfn_t gpfn = lpfn;
54	int err = 0;
55
56	set_xen_guest_handle(xatp.idxs, &idx);
57	set_xen_guest_handle(xatp.gpfns, &gpfn);
58	set_xen_guest_handle(xatp.errs, &err);
59
60	rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp);
61	return rc < 0 ? rc : err;
62}
63
64struct remap_data {
65	xen_pfn_t *fgmfn; /* foreign domain's gmfn */
66	pgprot_t prot;
67	domid_t  domid;
68	struct vm_area_struct *vma;
69	int index;
70	struct page **pages;
71	struct xen_remap_mfn_info *info;
72	int *err_ptr;
73	int mapped;
74};
75
76static int remap_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr,
77			void *data)
78{
79	struct remap_data *info = data;
80	struct page *page = info->pages[info->index++];
81	unsigned long pfn = page_to_pfn(page);
82	pte_t pte = pte_mkspecial(pfn_pte(pfn, info->prot));
83	int rc;
84
85	rc = map_foreign_page(pfn, *info->fgmfn, info->domid);
86	*info->err_ptr++ = rc;
87	if (!rc) {
88		set_pte_at(info->vma->vm_mm, addr, ptep, pte);
89		info->mapped++;
90	}
91	info->fgmfn++;
92
93	return 0;
94}
95
96int xen_xlate_remap_gfn_array(struct vm_area_struct *vma,
97			      unsigned long addr,
98			      xen_pfn_t *mfn, int nr,
99			      int *err_ptr, pgprot_t prot,
100			      unsigned domid,
101			      struct page **pages)
102{
103	int err;
104	struct remap_data data;
105	unsigned long range = nr << PAGE_SHIFT;
106
107	/* Kept here for the purpose of making sure code doesn't break
108	   x86 PVOPS */
109	BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_IO)) == (VM_PFNMAP | VM_IO)));
110
111	data.fgmfn = mfn;
112	data.prot  = prot;
113	data.domid = domid;
114	data.vma   = vma;
115	data.pages = pages;
116	data.index = 0;
117	data.err_ptr = err_ptr;
118	data.mapped = 0;
119
120	err = apply_to_page_range(vma->vm_mm, addr, range,
121				  remap_pte_fn, &data);
122	return err < 0 ? err : data.mapped;
123}
124EXPORT_SYMBOL_GPL(xen_xlate_remap_gfn_array);
125
126int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma,
127			      int nr, struct page **pages)
128{
129	int i;
130
131	for (i = 0; i < nr; i++) {
132		struct xen_remove_from_physmap xrp;
133		unsigned long pfn;
134
135		pfn = page_to_pfn(pages[i]);
136
137		xrp.domid = DOMID_SELF;
138		xrp.gpfn = pfn;
139		(void)HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp);
140	}
141	return 0;
142}
143EXPORT_SYMBOL_GPL(xen_xlate_unmap_gfn_range);
144