diff options
Diffstat (limited to 'drivers/xen/xlate_mmu.c')
| -rw-r--r-- | drivers/xen/xlate_mmu.c | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/drivers/xen/xlate_mmu.c b/drivers/xen/xlate_mmu.c new file mode 100644 index 000000000000..7724d90fc697 --- /dev/null +++ b/drivers/xen/xlate_mmu.c @@ -0,0 +1,133 @@ +/* + * 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 <asm/xen/hypercall.h> +#include <asm/xen/hypervisor.h> + +#include <xen/xen.h> +#include <xen/page.h> +#include <xen/interface/xen.h> +#include <xen/interface/memory.h> + +/* map fgmfn of domid to lpfn in the current domain */ +static int map_foreign_page(unsigned long lpfn, unsigned long fgmfn, + unsigned int domid) +{ + int rc; + struct xen_add_to_physmap_range xatp = { + .domid = DOMID_SELF, + .foreign_domid = domid, + .size = 1, + .space = XENMAPSPACE_gmfn_foreign, + }; + xen_ulong_t idx = fgmfn; + xen_pfn_t gpfn = lpfn; + int err = 0; + + set_xen_guest_handle(xatp.idxs, &idx); + set_xen_guest_handle(xatp.gpfns, &gpfn); + set_xen_guest_handle(xatp.errs, &err); + + rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp); + return rc < 0 ? rc : err; +} + +struct remap_data { + xen_pfn_t fgmfn; /* foreign domain's gmfn */ + pgprot_t prot; + domid_t domid; + struct vm_area_struct *vma; + int index; + struct page **pages; + struct xen_remap_mfn_info *info; +}; + +static int remap_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr, + void *data) +{ + struct remap_data *info = data; + struct page *page = info->pages[info->index++]; + unsigned long pfn = page_to_pfn(page); + pte_t pte = pte_mkspecial(pfn_pte(pfn, info->prot)); + int rc; + + rc = map_foreign_page(pfn, info->fgmfn, info->domid); + if (rc < 0) + return rc; + set_pte_at(info->vma->vm_mm, addr, ptep, pte); + + return 0; +} + +int xen_xlate_remap_gfn_range(struct vm_area_struct *vma, + unsigned long addr, + xen_pfn_t gfn, int nr, + pgprot_t prot, unsigned domid, + struct page **pages) +{ + int err; + struct remap_data data; + + /* TBD: Batching, current sole caller only does page at a time */ + if (nr > 1) + return -EINVAL; + + data.fgmfn = gfn; + data.prot = prot; + data.domid = domid; + data.vma = vma; + data.index = 0; + data.pages = pages; + err = apply_to_page_range(vma->vm_mm, addr, nr << PAGE_SHIFT, + remap_pte_fn, &data); + return err; +} +EXPORT_SYMBOL_GPL(xen_xlate_remap_gfn_range); + +int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma, + int nr, struct page **pages) +{ + int i; + + for (i = 0; i < nr; i++) { + struct xen_remove_from_physmap xrp; + unsigned long pfn; + + pfn = page_to_pfn(pages[i]); + + xrp.domid = DOMID_SELF; + xrp.gpfn = pfn; + (void)HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp); + } + return 0; +} +EXPORT_SYMBOL_GPL(xen_xlate_unmap_gfn_range); |