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-rw-r--r--drivers/xen/xlate_mmu.c295
1 files changed, 295 insertions, 0 deletions
diff --git a/drivers/xen/xlate_mmu.c b/drivers/xen/xlate_mmu.c
new file mode 100644
index 000000000..f17c4c03d
--- /dev/null
+++ b/drivers/xen/xlate_mmu.c
@@ -0,0 +1,295 @@
+/*
+ * MMU operations common to all auto-translated physmap guests.
+ *
+ * Copyright (C) 2015 Citrix Systems R&D Ltd.
+ *
+ * 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; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+
+#include <asm/xen/hypercall.h>
+#include <asm/xen/hypervisor.h>
+
+#include <xen/xen.h>
+#include <xen/xen-ops.h>
+#include <xen/page.h>
+#include <xen/interface/xen.h>
+#include <xen/interface/memory.h>
+#include <xen/balloon.h>
+
+typedef void (*xen_gfn_fn_t)(unsigned long gfn, void *data);
+
+/* Break down the pages in 4KB chunk and call fn for each gfn */
+static void xen_for_each_gfn(struct page **pages, unsigned nr_gfn,
+ xen_gfn_fn_t fn, void *data)
+{
+ unsigned long xen_pfn = 0;
+ struct page *page;
+ int i;
+
+ for (i = 0; i < nr_gfn; i++) {
+ if ((i % XEN_PFN_PER_PAGE) == 0) {
+ page = pages[i / XEN_PFN_PER_PAGE];
+ xen_pfn = page_to_xen_pfn(page);
+ }
+ fn(pfn_to_gfn(xen_pfn++), data);
+ }
+}
+
+struct remap_data {
+ xen_pfn_t *fgfn; /* foreign domain's gfn */
+ int nr_fgfn; /* Number of foreign gfn left to map */
+ pgprot_t prot;
+ domid_t domid;
+ struct vm_area_struct *vma;
+ int index;
+ struct page **pages;
+ struct xen_remap_gfn_info *info;
+ int *err_ptr;
+ int mapped;
+
+ /* Hypercall parameters */
+ int h_errs[XEN_PFN_PER_PAGE];
+ xen_ulong_t h_idxs[XEN_PFN_PER_PAGE];
+ xen_pfn_t h_gpfns[XEN_PFN_PER_PAGE];
+
+ int h_iter; /* Iterator */
+};
+
+static void setup_hparams(unsigned long gfn, void *data)
+{
+ struct remap_data *info = data;
+
+ info->h_idxs[info->h_iter] = *info->fgfn;
+ info->h_gpfns[info->h_iter] = gfn;
+ info->h_errs[info->h_iter] = 0;
+
+ info->h_iter++;
+ info->fgfn++;
+}
+
+static int remap_pte_fn(pte_t *ptep, unsigned long addr, void *data)
+{
+ struct remap_data *info = data;
+ struct page *page = info->pages[info->index++];
+ pte_t pte = pte_mkspecial(pfn_pte(page_to_pfn(page), info->prot));
+ int rc, nr_gfn;
+ uint32_t i;
+ struct xen_add_to_physmap_range xatp = {
+ .domid = DOMID_SELF,
+ .foreign_domid = info->domid,
+ .space = XENMAPSPACE_gmfn_foreign,
+ };
+
+ nr_gfn = min_t(typeof(info->nr_fgfn), XEN_PFN_PER_PAGE, info->nr_fgfn);
+ info->nr_fgfn -= nr_gfn;
+
+ info->h_iter = 0;
+ xen_for_each_gfn(&page, nr_gfn, setup_hparams, info);
+ BUG_ON(info->h_iter != nr_gfn);
+
+ set_xen_guest_handle(xatp.idxs, info->h_idxs);
+ set_xen_guest_handle(xatp.gpfns, info->h_gpfns);
+ set_xen_guest_handle(xatp.errs, info->h_errs);
+ xatp.size = nr_gfn;
+
+ rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp);
+
+ /* info->err_ptr expect to have one error status per Xen PFN */
+ for (i = 0; i < nr_gfn; i++) {
+ int err = (rc < 0) ? rc : info->h_errs[i];
+
+ *(info->err_ptr++) = err;
+ if (!err)
+ info->mapped++;
+ }
+
+ /*
+ * Note: The hypercall will return 0 in most of the case if even if
+ * all the fgmfn are not mapped. We still have to update the pte
+ * as the userspace may decide to continue.
+ */
+ if (!rc)
+ set_pte_at(info->vma->vm_mm, addr, ptep, pte);
+
+ return 0;
+}
+
+int xen_xlate_remap_gfn_array(struct vm_area_struct *vma,
+ unsigned long addr,
+ xen_pfn_t *gfn, int nr,
+ int *err_ptr, pgprot_t prot,
+ unsigned domid,
+ struct page **pages)
+{
+ int err;
+ struct remap_data data;
+ unsigned long range = DIV_ROUND_UP(nr, XEN_PFN_PER_PAGE) << PAGE_SHIFT;
+
+ /* Kept here for the purpose of making sure code doesn't break
+ x86 PVOPS */
+ BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_IO)) == (VM_PFNMAP | VM_IO)));
+
+ data.fgfn = gfn;
+ data.nr_fgfn = nr;
+ data.prot = prot;
+ data.domid = domid;
+ data.vma = vma;
+ data.pages = pages;
+ data.index = 0;
+ data.err_ptr = err_ptr;
+ data.mapped = 0;
+
+ err = apply_to_page_range(vma->vm_mm, addr, range,
+ remap_pte_fn, &data);
+ return err < 0 ? err : data.mapped;
+}
+EXPORT_SYMBOL_GPL(xen_xlate_remap_gfn_array);
+
+static void unmap_gfn(unsigned long gfn, void *data)
+{
+ struct xen_remove_from_physmap xrp;
+
+ xrp.domid = DOMID_SELF;
+ xrp.gpfn = gfn;
+ (void)HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp);
+}
+
+int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma,
+ int nr, struct page **pages)
+{
+ xen_for_each_gfn(pages, nr, unmap_gfn, NULL);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(xen_xlate_unmap_gfn_range);
+
+struct map_balloon_pages {
+ xen_pfn_t *pfns;
+ unsigned int idx;
+};
+
+static void setup_balloon_gfn(unsigned long gfn, void *data)
+{
+ struct map_balloon_pages *info = data;
+
+ info->pfns[info->idx++] = gfn;
+}
+
+/**
+ * xen_xlate_map_ballooned_pages - map a new set of ballooned pages
+ * @gfns: returns the array of corresponding GFNs
+ * @virt: returns the virtual address of the mapped region
+ * @nr_grant_frames: number of GFNs
+ * @return 0 on success, error otherwise
+ *
+ * This allocates a set of ballooned pages and maps them into the
+ * kernel's address space.
+ */
+int __init xen_xlate_map_ballooned_pages(xen_pfn_t **gfns, void **virt,
+ unsigned long nr_grant_frames)
+{
+ struct page **pages;
+ xen_pfn_t *pfns;
+ void *vaddr;
+ struct map_balloon_pages data;
+ int rc;
+ unsigned long nr_pages;
+
+ BUG_ON(nr_grant_frames == 0);
+ nr_pages = DIV_ROUND_UP(nr_grant_frames, XEN_PFN_PER_PAGE);
+ pages = kcalloc(nr_pages, sizeof(pages[0]), GFP_KERNEL);
+ if (!pages)
+ return -ENOMEM;
+
+ pfns = kcalloc(nr_grant_frames, sizeof(pfns[0]), GFP_KERNEL);
+ if (!pfns) {
+ kfree(pages);
+ return -ENOMEM;
+ }
+ rc = xen_alloc_unpopulated_pages(nr_pages, pages);
+ if (rc) {
+ pr_warn("%s Couldn't balloon alloc %ld pages rc:%d\n", __func__,
+ nr_pages, rc);
+ kfree(pages);
+ kfree(pfns);
+ return rc;
+ }
+
+ data.pfns = pfns;
+ data.idx = 0;
+ xen_for_each_gfn(pages, nr_grant_frames, setup_balloon_gfn, &data);
+
+ vaddr = vmap(pages, nr_pages, 0, PAGE_KERNEL);
+ if (!vaddr) {
+ pr_warn("%s Couldn't map %ld pages rc:%d\n", __func__,
+ nr_pages, rc);
+ xen_free_unpopulated_pages(nr_pages, pages);
+ kfree(pages);
+ kfree(pfns);
+ return -ENOMEM;
+ }
+ kfree(pages);
+
+ *gfns = pfns;
+ *virt = vaddr;
+
+ return 0;
+}
+
+struct remap_pfn {
+ struct mm_struct *mm;
+ struct page **pages;
+ pgprot_t prot;
+ unsigned long i;
+};
+
+static int remap_pfn_fn(pte_t *ptep, unsigned long addr, void *data)
+{
+ struct remap_pfn *r = data;
+ struct page *page = r->pages[r->i];
+ pte_t pte = pte_mkspecial(pfn_pte(page_to_pfn(page), r->prot));
+
+ set_pte_at(r->mm, addr, ptep, pte);
+ r->i++;
+
+ return 0;
+}
+
+/* Used by the privcmd module, but has to be built-in on ARM */
+int xen_remap_vma_range(struct vm_area_struct *vma, unsigned long addr, unsigned long len)
+{
+ struct remap_pfn r = {
+ .mm = vma->vm_mm,
+ .pages = vma->vm_private_data,
+ .prot = vma->vm_page_prot,
+ };
+
+ return apply_to_page_range(vma->vm_mm, addr, len, remap_pfn_fn, &r);
+}
+EXPORT_SYMBOL_GPL(xen_remap_vma_range);