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>
32 #include <linux/slab.h>
33 #include <linux/vmalloc.h>
35 #include <asm/xen/hypercall.h>
36 #include <asm/xen/hypervisor.h>
39 #include <xen/xen-ops.h>
41 #include <xen/interface/xen.h>
42 #include <xen/interface/memory.h>
43 #include <xen/balloon.h>
45 typedef void (*xen_gfn_fn_t)(unsigned long gfn, void *data);
47 /* Break down the pages in 4KB chunk and call fn for each gfn */
48 static void xen_for_each_gfn(struct page **pages, unsigned nr_gfn,
49 xen_gfn_fn_t fn, void *data)
51 unsigned long xen_pfn = 0;
55 for (i = 0; i < nr_gfn; i++) {
56 if ((i % XEN_PFN_PER_PAGE) == 0) {
57 page = pages[i / XEN_PFN_PER_PAGE];
58 xen_pfn = page_to_xen_pfn(page);
60 fn(pfn_to_gfn(xen_pfn++), data);
65 xen_pfn_t *fgfn; /* foreign domain's gfn */
66 int nr_fgfn; /* Number of foreign gfn left to map */
69 struct vm_area_struct *vma;
72 struct xen_remap_gfn_info *info;
76 /* Hypercall parameters */
77 int h_errs[XEN_PFN_PER_PAGE];
78 xen_ulong_t h_idxs[XEN_PFN_PER_PAGE];
79 xen_pfn_t h_gpfns[XEN_PFN_PER_PAGE];
81 int h_iter; /* Iterator */
84 static void setup_hparams(unsigned long gfn, void *data)
86 struct remap_data *info = data;
88 info->h_idxs[info->h_iter] = *info->fgfn;
89 info->h_gpfns[info->h_iter] = gfn;
90 info->h_errs[info->h_iter] = 0;
96 static int remap_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr,
99 struct remap_data *info = data;
100 struct page *page = info->pages[info->index++];
101 pte_t pte = pte_mkspecial(pfn_pte(page_to_pfn(page), info->prot));
104 struct xen_add_to_physmap_range xatp = {
106 .foreign_domid = info->domid,
107 .space = XENMAPSPACE_gmfn_foreign,
110 nr_gfn = min_t(typeof(info->nr_fgfn), XEN_PFN_PER_PAGE, info->nr_fgfn);
111 info->nr_fgfn -= nr_gfn;
114 xen_for_each_gfn(&page, nr_gfn, setup_hparams, info);
115 BUG_ON(info->h_iter != nr_gfn);
117 set_xen_guest_handle(xatp.idxs, info->h_idxs);
118 set_xen_guest_handle(xatp.gpfns, info->h_gpfns);
119 set_xen_guest_handle(xatp.errs, info->h_errs);
122 rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp);
124 /* info->err_ptr expect to have one error status per Xen PFN */
125 for (i = 0; i < nr_gfn; i++) {
126 int err = (rc < 0) ? rc : info->h_errs[i];
128 *(info->err_ptr++) = err;
134 * Note: The hypercall will return 0 in most of the case if even if
135 * all the fgmfn are not mapped. We still have to update the pte
136 * as the userspace may decide to continue.
139 set_pte_at(info->vma->vm_mm, addr, ptep, pte);
144 int xen_xlate_remap_gfn_array(struct vm_area_struct *vma,
146 xen_pfn_t *gfn, int nr,
147 int *err_ptr, pgprot_t prot,
152 struct remap_data data;
153 unsigned long range = DIV_ROUND_UP(nr, XEN_PFN_PER_PAGE) << PAGE_SHIFT;
155 /* Kept here for the purpose of making sure code doesn't break
157 BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_IO)) == (VM_PFNMAP | VM_IO)));
166 data.err_ptr = err_ptr;
169 err = apply_to_page_range(vma->vm_mm, addr, range,
170 remap_pte_fn, &data);
171 return err < 0 ? err : data.mapped;
173 EXPORT_SYMBOL_GPL(xen_xlate_remap_gfn_array);
175 static void unmap_gfn(unsigned long gfn, void *data)
177 struct xen_remove_from_physmap xrp;
179 xrp.domid = DOMID_SELF;
181 (void)HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp);
184 int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma,
185 int nr, struct page **pages)
187 xen_for_each_gfn(pages, nr, unmap_gfn, NULL);
191 EXPORT_SYMBOL_GPL(xen_xlate_unmap_gfn_range);
193 struct map_balloon_pages {
198 static void setup_balloon_gfn(unsigned long gfn, void *data)
200 struct map_balloon_pages *info = data;
202 info->pfns[info->idx++] = gfn;
206 * xen_xlate_map_ballooned_pages - map a new set of ballooned pages
207 * @gfns: returns the array of corresponding GFNs
208 * @virt: returns the virtual address of the mapped region
209 * @nr_grant_frames: number of GFNs
210 * @return 0 on success, error otherwise
212 * This allocates a set of ballooned pages and maps them into the
213 * kernel's address space.
215 int __init xen_xlate_map_ballooned_pages(xen_pfn_t **gfns, void **virt,
216 unsigned long nr_grant_frames)
221 struct map_balloon_pages data;
223 unsigned long nr_pages;
225 BUG_ON(nr_grant_frames == 0);
226 nr_pages = DIV_ROUND_UP(nr_grant_frames, XEN_PFN_PER_PAGE);
227 pages = kcalloc(nr_pages, sizeof(pages[0]), GFP_KERNEL);
231 pfns = kcalloc(nr_grant_frames, sizeof(pfns[0]), GFP_KERNEL);
236 rc = alloc_xenballooned_pages(nr_pages, pages);
238 pr_warn("%s Couldn't balloon alloc %ld pages rc:%d\n", __func__,
247 xen_for_each_gfn(pages, nr_grant_frames, setup_balloon_gfn, &data);
249 vaddr = vmap(pages, nr_pages, 0, PAGE_KERNEL);
251 pr_warn("%s Couldn't map %ld pages rc:%d\n", __func__,
253 free_xenballooned_pages(nr_pages, pages);
265 EXPORT_SYMBOL_GPL(xen_xlate_map_ballooned_pages);