diff options
Diffstat (limited to 'drivers/xen/privcmd.c')
| -rw-r--r-- | drivers/xen/privcmd.c | 135 |
1 files changed, 134 insertions, 1 deletions
diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c index 1c909183c42a..8ae0349d9f0a 100644 --- a/drivers/xen/privcmd.c +++ b/drivers/xen/privcmd.c @@ -33,6 +33,7 @@ #include <xen/xen.h> #include <xen/privcmd.h> #include <xen/interface/xen.h> +#include <xen/interface/memory.h> #include <xen/interface/hvm/dm_op.h> #include <xen/features.h> #include <xen/page.h> @@ -722,6 +723,134 @@ static long privcmd_ioctl_restrict(struct file *file, void __user *udata) 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, pgtable_t token, 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; +} + +static long privcmd_ioctl_mmap_resource(struct file *file, void __user *udata) +{ + struct privcmd_data *data = file->private_data; + struct mm_struct *mm = current->mm; + struct vm_area_struct *vma; + struct privcmd_mmap_resource kdata; + xen_pfn_t *pfns = NULL; + struct xen_mem_acquire_resource xdata; + int rc; + + if (copy_from_user(&kdata, udata, sizeof(kdata))) + return -EFAULT; + + /* If restriction is in place, check the domid matches */ + if (data->domid != DOMID_INVALID && data->domid != kdata.dom) + return -EPERM; + + down_write(&mm->mmap_sem); + + vma = find_vma(mm, kdata.addr); + if (!vma || vma->vm_ops != &privcmd_vm_ops) { + rc = -EINVAL; + goto out; + } + + pfns = kcalloc(kdata.num, sizeof(*pfns), GFP_KERNEL); + if (!pfns) { + rc = -ENOMEM; + goto out; + } + + if (xen_feature(XENFEAT_auto_translated_physmap)) { + unsigned int nr = DIV_ROUND_UP(kdata.num, XEN_PFN_PER_PAGE); + struct page **pages; + unsigned int i; + + rc = alloc_empty_pages(vma, nr); + if (rc < 0) + goto out; + + pages = vma->vm_private_data; + for (i = 0; i < kdata.num; i++) { + xen_pfn_t pfn = + page_to_xen_pfn(pages[i / XEN_PFN_PER_PAGE]); + + pfns[i] = pfn + (i % XEN_PFN_PER_PAGE); + } + } else + vma->vm_private_data = PRIV_VMA_LOCKED; + + memset(&xdata, 0, sizeof(xdata)); + xdata.domid = kdata.dom; + xdata.type = kdata.type; + xdata.id = kdata.id; + xdata.frame = kdata.idx; + xdata.nr_frames = kdata.num; + set_xen_guest_handle(xdata.frame_list, pfns); + + xen_preemptible_hcall_begin(); + rc = HYPERVISOR_memory_op(XENMEM_acquire_resource, &xdata); + xen_preemptible_hcall_end(); + + if (rc) + goto out; + + if (xen_feature(XENFEAT_auto_translated_physmap)) { + struct remap_pfn r = { + .mm = vma->vm_mm, + .pages = vma->vm_private_data, + .prot = vma->vm_page_prot, + }; + + rc = apply_to_page_range(r.mm, kdata.addr, + kdata.num << PAGE_SHIFT, + remap_pfn_fn, &r); + } else { + unsigned int domid = + (xdata.flags & XENMEM_rsrc_acq_caller_owned) ? + DOMID_SELF : kdata.dom; + int num; + + num = xen_remap_domain_mfn_array(vma, + kdata.addr & PAGE_MASK, + pfns, kdata.num, (int *)pfns, + vma->vm_page_prot, + domid, + vma->vm_private_data); + if (num < 0) + rc = num; + else if (num != kdata.num) { + unsigned int i; + + for (i = 0; i < num; i++) { + rc = pfns[i]; + if (rc < 0) + break; + } + } else + rc = 0; + } + +out: + up_write(&mm->mmap_sem); + kfree(pfns); + + return rc; +} + static long privcmd_ioctl(struct file *file, unsigned int cmd, unsigned long data) { @@ -753,6 +882,10 @@ static long privcmd_ioctl(struct file *file, ret = privcmd_ioctl_restrict(file, udata); break; + case IOCTL_PRIVCMD_MMAP_RESOURCE: + ret = privcmd_ioctl_mmap_resource(file, udata); + break; + default: break; } @@ -801,7 +934,7 @@ static void privcmd_close(struct vm_area_struct *vma) kfree(pages); } -static int privcmd_fault(struct vm_fault *vmf) +static vm_fault_t privcmd_fault(struct vm_fault *vmf) { printk(KERN_DEBUG "privcmd_fault: vma=%p %lx-%lx, pgoff=%lx, uv=%p\n", vmf->vma, vmf->vma->vm_start, vmf->vma->vm_end, |