2 * MMU operations common to all auto-translated physmap guests.
4 * Copyright (C) 2015 Citrix Systems R&D Ltd.
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:
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:
19 * The above copyright notice and this permission notice shall be included in
20 * all copies or substantial portions of the Software.
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
30 #include <linux/kernel.h>
33 #include <asm/xen/hypercall.h>
34 #include <asm/xen/hypervisor.h>
38 #include <xen/interface/xen.h>
39 #include <xen/interface/memory.h>
41 typedef void (*xen_gfn_fn_t)(unsigned long gfn, void *data);
43 /* Break down the pages in 4KB chunk and call fn for each gfn */
44 static void xen_for_each_gfn(struct page **pages, unsigned nr_gfn,
45 xen_gfn_fn_t fn, void *data)
47 unsigned long xen_pfn = 0;
51 for (i = 0; i < nr_gfn; i++) {
52 if ((i % XEN_PFN_PER_PAGE) == 0) {
53 page = pages[i / XEN_PFN_PER_PAGE];
54 xen_pfn = page_to_xen_pfn(page);
56 fn(pfn_to_gfn(xen_pfn++), data);
61 xen_pfn_t *fgfn; /* foreign domain's gfn */
62 int nr_fgfn; /* Number of foreign gfn left to map */
65 struct vm_area_struct *vma;
68 struct xen_remap_gfn_info *info;
72 /* Hypercall parameters */
73 int h_errs[XEN_PFN_PER_PAGE];
74 xen_ulong_t h_idxs[XEN_PFN_PER_PAGE];
75 xen_pfn_t h_gpfns[XEN_PFN_PER_PAGE];
77 int h_iter; /* Iterator */
80 static void setup_hparams(unsigned long gfn, void *data)
82 struct remap_data *info = data;
84 info->h_idxs[info->h_iter] = *info->fgfn;
85 info->h_gpfns[info->h_iter] = gfn;
86 info->h_errs[info->h_iter] = 0;
92 static int remap_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr,
95 struct remap_data *info = data;
96 struct page *page = info->pages[info->index++];
97 pte_t pte = pte_mkspecial(pfn_pte(page_to_pfn(page), info->prot));
100 struct xen_add_to_physmap_range xatp = {
102 .foreign_domid = info->domid,
103 .space = XENMAPSPACE_gmfn_foreign,
106 nr_gfn = min_t(typeof(info->nr_fgfn), XEN_PFN_PER_PAGE, info->nr_fgfn);
107 info->nr_fgfn -= nr_gfn;
110 xen_for_each_gfn(&page, nr_gfn, setup_hparams, info);
111 BUG_ON(info->h_iter != nr_gfn);
113 set_xen_guest_handle(xatp.idxs, info->h_idxs);
114 set_xen_guest_handle(xatp.gpfns, info->h_gpfns);
115 set_xen_guest_handle(xatp.errs, info->h_errs);
118 rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp);
120 /* info->err_ptr expect to have one error status per Xen PFN */
121 for (i = 0; i < nr_gfn; i++) {
122 int err = (rc < 0) ? rc : info->h_errs[i];
124 *(info->err_ptr++) = err;
130 * Note: The hypercall will return 0 in most of the case if even if
131 * all the fgmfn are not mapped. We still have to update the pte
132 * as the userspace may decide to continue.
135 set_pte_at(info->vma->vm_mm, addr, ptep, pte);
140 int xen_xlate_remap_gfn_array(struct vm_area_struct *vma,
142 xen_pfn_t *gfn, int nr,
143 int *err_ptr, pgprot_t prot,
148 struct remap_data data;
149 unsigned long range = DIV_ROUND_UP(nr, XEN_PFN_PER_PAGE) << PAGE_SHIFT;
151 /* Kept here for the purpose of making sure code doesn't break
153 BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_IO)) == (VM_PFNMAP | VM_IO)));
162 data.err_ptr = err_ptr;
165 err = apply_to_page_range(vma->vm_mm, addr, range,
166 remap_pte_fn, &data);
167 return err < 0 ? err : data.mapped;
169 EXPORT_SYMBOL_GPL(xen_xlate_remap_gfn_array);
171 static void unmap_gfn(unsigned long gfn, void *data)
173 struct xen_remove_from_physmap xrp;
175 xrp.domid = DOMID_SELF;
177 (void)HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp);
180 int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma,
181 int nr, struct page **pages)
183 xen_for_each_gfn(pages, nr, unmap_gfn, NULL);
187 EXPORT_SYMBOL_GPL(xen_xlate_unmap_gfn_range);