--- /dev/null
+/******************************************************************************
+ * grant_table.c
+ * x86 specific part
+ *
+ * Granting foreign access to our memory reservation.
+ *
+ * Copyright (c) 2005-2006, Christopher Clark
+ * Copyright (c) 2004-2005, K A Fraser
+ * Copyright (c) 2008 Isaku Yamahata <yamahata at valinux co jp>
+ * VA Linux Systems Japan. Split out x86 specific part.
+ *
+ * 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/sched.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+
+#include <xen/interface/xen.h>
+#include <xen/page.h>
+#include <xen/grant_table.h>
+#include <xen/xen.h>
+
+#include <asm/pgtable.h>
+
+static struct gnttab_vm_area {
+ struct vm_struct *area;
+ pte_t **ptes;
+} gnttab_shared_vm_area;
+
+int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
+ unsigned long max_nr_gframes,
+ void **__shared)
+{
+ void *shared = *__shared;
+ unsigned long addr;
+ unsigned long i;
+
+ if (shared == NULL)
+ *__shared = shared = gnttab_shared_vm_area.area->addr;
+
+ addr = (unsigned long)shared;
+
+ for (i = 0; i < nr_gframes; i++) {
+ set_pte_at(&init_mm, addr, gnttab_shared_vm_area.ptes[i],
+ mfn_pte(frames[i], PAGE_KERNEL));
+ addr += PAGE_SIZE;
+ }
+
+ return 0;
+}
+
+void arch_gnttab_unmap(void *shared, unsigned long nr_gframes)
+{
+ unsigned long addr;
+ unsigned long i;
+
+ addr = (unsigned long)shared;
+
+ for (i = 0; i < nr_gframes; i++) {
+ set_pte_at(&init_mm, addr, gnttab_shared_vm_area.ptes[i],
+ __pte(0));
+ addr += PAGE_SIZE;
+ }
+}
+
+static int arch_gnttab_valloc(struct gnttab_vm_area *area, unsigned nr_frames)
+{
+ area->ptes = kmalloc(sizeof(pte_t *) * nr_frames, GFP_KERNEL);
+ if (area->ptes == NULL)
+ return -ENOMEM;
+
+ area->area = alloc_vm_area(PAGE_SIZE * nr_frames, area->ptes);
+ if (area->area == NULL) {
+ kfree(area->ptes);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+int arch_gnttab_init(unsigned long nr_shared)
+{
+ if (!xen_pv_domain())
+ return 0;
+
+ return arch_gnttab_valloc(&gnttab_shared_vm_area, nr_shared);
+}
+
+#ifdef CONFIG_XEN_PVH
+#include <xen/balloon.h>
+#include <xen/events.h>
+#include <linux/slab.h>
+static int __init xlated_setup_gnttab_pages(void)
+{
+ struct page **pages;
+ xen_pfn_t *pfns;
+ void *vaddr;
+ int rc;
+ unsigned int i;
+ unsigned long nr_grant_frames = gnttab_max_grant_frames();
+
+ BUG_ON(nr_grant_frames == 0);
+ pages = kcalloc(nr_grant_frames, 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 = alloc_xenballooned_pages(nr_grant_frames, pages, 0 /* lowmem */);
+ if (rc) {
+ pr_warn("%s Couldn't balloon alloc %ld pfns rc:%d\n", __func__,
+ nr_grant_frames, rc);
+ kfree(pages);
+ kfree(pfns);
+ return rc;
+ }
+ for (i = 0; i < nr_grant_frames; i++)
+ pfns[i] = page_to_pfn(pages[i]);
+
+ vaddr = vmap(pages, nr_grant_frames, 0, PAGE_KERNEL);
+ if (!vaddr) {
+ pr_warn("%s Couldn't map %ld pfns rc:%d\n", __func__,
+ nr_grant_frames, rc);
+ free_xenballooned_pages(nr_grant_frames, pages);
+ kfree(pages);
+ kfree(pfns);
+ return -ENOMEM;
+ }
+ kfree(pages);
+
+ xen_auto_xlat_grant_frames.pfn = pfns;
+ xen_auto_xlat_grant_frames.count = nr_grant_frames;
+ xen_auto_xlat_grant_frames.vaddr = vaddr;
+
+ return 0;
+}
+
+static int __init xen_pvh_gnttab_setup(void)
+{
+ if (!xen_pvh_domain())
+ return -ENODEV;
+
+ return xlated_setup_gnttab_pages();
+}
+/* Call it _before_ __gnttab_init as we need to initialize the
+ * xen_auto_xlat_grant_frames first. */
+core_initcall(xen_pvh_gnttab_setup);
+#endif
Code Review / kvmfornfv.git / blobdiff