Merge branch 'disintegrate-asm-generic' of git://git.infradead.org/users/dhowells/linux-headers into asm-generic

Patches from David Howells <dhowells@redhat.com>:

This is to complete part of the UAPI disintegration for which the
preparatory patches were pulled recently.

Note that there are some fixup patches which are at the base of the
branch aimed at you, plus all arches get the asm-generic branch merged in too.

* 'disintegrate-asm-generic' of git://git.infradead.org/users/dhowells/linux-headers:
  UAPI: (Scripted) Disintegrate include/asm-generic
  UAPI: Fix conditional header installation handling (notably kvm_para.h on m68k)
  c6x: remove c6x signal.h
  UAPI: Split compound conditionals containing __KERNEL__ in Arm64
  UAPI: Fix the guards on various asm/unistd.h files

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 102 insertions, 33 deletions

diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c
index ccee0f16bcf..ef6389580b8 100644
--- a/drivers/xen/privcmd.c
+++ b/drivers/xen/privcmd.c
@@ -76,7 +76,7 @@ static void free_page_list(struct list_head *pages)
  */
 static int gather_array(struct list_head *pagelist,
 			unsigned nelem, size_t size,
-			void __user *data)
+			const void __user *data)
 {
 	unsigned pageidx;
 	void *pagedata;
@@ -246,61 +246,117 @@ struct mmap_batch_state {
 	domid_t domain;
 	unsigned long va;
 	struct vm_area_struct *vma;
-	int err;
-
-	xen_pfn_t __user *user;
+	/* A tristate:
+	 *      0 for no errors
+	 *      1 if at least one error has happened (and no
+	 *          -ENOENT errors have happened)
+	 *      -ENOENT if at least 1 -ENOENT has happened.
+	 */
+	int global_error;
+	/* An array for individual errors */
+	int *err;
+
+	/* User-space mfn array to store errors in the second pass for V1. */
+	xen_pfn_t __user *user_mfn;
 };
 
 static int mmap_batch_fn(void *data, void *state)
 {
 	xen_pfn_t *mfnp = data;
 	struct mmap_batch_state *st = state;
+	int ret;
+
+	ret = xen_remap_domain_mfn_range(st->vma, st->va & PAGE_MASK, *mfnp, 1,
+					 st->vma->vm_page_prot, st->domain);
 
-	if (xen_remap_domain_mfn_range(st->vma, st->va & PAGE_MASK, *mfnp, 1,
-				       st->vma->vm_page_prot, st->domain) < 0) {
-		*mfnp |= 0xf0000000U;
-		st->err++;
+	/* Store error code for second pass. */
+	*(st->err++) = ret;
+
+	/* And see if it affects the global_error. */
+	if (ret < 0) {
+		if (ret == -ENOENT)
+			st->global_error = -ENOENT;
+		else {
+			/* Record that at least one error has happened. */
+			if (st->global_error == 0)
+				st->global_error = 1;
+		}
 	}
 	st->va += PAGE_SIZE;
 
 	return 0;
 }
 
-static int mmap_return_errors(void *data, void *state)
+static int mmap_return_errors_v1(void *data, void *state)
 {
 	xen_pfn_t *mfnp = data;
 	struct mmap_batch_state *st = state;
-
-	return put_user(*mfnp, st->user++);
+	int err = *(st->err++);
+
+	/*
+	 * V1 encodes the error codes in the 32bit top nibble of the
+	 * mfn (with its known limitations vis-a-vis 64 bit callers).
+	 */
+	*mfnp |= (err == -ENOENT) ?
+				PRIVCMD_MMAPBATCH_PAGED_ERROR :
+				PRIVCMD_MMAPBATCH_MFN_ERROR;
+	return __put_user(*mfnp, st->user_mfn++);
 }
 
 static struct vm_operations_struct privcmd_vm_ops;
 
-static long privcmd_ioctl_mmap_batch(void __user *udata)
+static long privcmd_ioctl_mmap_batch(void __user *udata, int version)
 {
 	int ret;
-	struct privcmd_mmapbatch m;
+	struct privcmd_mmapbatch_v2 m;
 	struct mm_struct *mm = current->mm;
 	struct vm_area_struct *vma;
 	unsigned long nr_pages;
 	LIST_HEAD(pagelist);
+	int *err_array = NULL;
 	struct mmap_batch_state state;
 
 	if (!xen_initial_domain())
 		return -EPERM;
 
-	if (copy_from_user(&m, udata, sizeof(m)))
-		return -EFAULT;
+	switch (version) {
+	case 1:
+		if (copy_from_user(&m, udata, sizeof(struct privcmd_mmapbatch)))
+			return -EFAULT;
+		/* Returns per-frame error in m.arr. */
+		m.err = NULL;
+		if (!access_ok(VERIFY_WRITE, m.arr, m.num * sizeof(*m.arr)))
+			return -EFAULT;
+		break;
+	case 2:
+		if (copy_from_user(&m, udata, sizeof(struct privcmd_mmapbatch_v2)))
+			return -EFAULT;
+		/* Returns per-frame error code in m.err. */
+		if (!access_ok(VERIFY_WRITE, m.err, m.num * (sizeof(*m.err))))
+			return -EFAULT;
+		break;
+	default:
+		return -EINVAL;
+	}
 
 	nr_pages = m.num;
 	if ((m.num <= 0) || (nr_pages > (LONG_MAX >> PAGE_SHIFT)))
 		return -EINVAL;
 
-	ret = gather_array(&pagelist, m.num, sizeof(xen_pfn_t),
-			   m.arr);
+	ret = gather_array(&pagelist, m.num, sizeof(xen_pfn_t), m.arr);
 
-	if (ret || list_empty(&pagelist))
+	if (ret)
 		goto out;
+	if (list_empty(&pagelist)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	err_array = kcalloc(m.num, sizeof(int), GFP_KERNEL);
+	if (err_array == NULL) {
+		ret = -ENOMEM;
+		goto out;
+	}
 
 	down_write(&mm->mmap_sem);
 
@@ -315,24 +371,37 @@ static long privcmd_ioctl_mmap_batch(void __user *udata)
 		goto out;
 	}
 
-	state.domain = m.dom;
-	state.vma = vma;
-	state.va = m.addr;
-	state.err = 0;
+	state.domain        = m.dom;
+	state.vma           = vma;
+	state.va            = m.addr;
+	state.global_error  = 0;
+	state.err           = err_array;
 
-	ret = traverse_pages(m.num, sizeof(xen_pfn_t),
-			     &pagelist, mmap_batch_fn, &state);
+	/* mmap_batch_fn guarantees ret == 0 */
+	BUG_ON(traverse_pages(m.num, sizeof(xen_pfn_t),
+			     &pagelist, mmap_batch_fn, &state));
 
 	up_write(&mm->mmap_sem);
 
-	if (state.err > 0) {
-		state.user = m.arr;
+	if (state.global_error && (version == 1)) {
+		/* Write back errors in second pass. */
+		state.user_mfn = (xen_pfn_t *)m.arr;
+		state.err      = err_array;
 		ret = traverse_pages(m.num, sizeof(xen_pfn_t),
-			       &pagelist,
-			       mmap_return_errors, &state);
+				     &pagelist, mmap_return_errors_v1, &state);
+	} else if (version == 2) {
+		ret = __copy_to_user(m.err, err_array, m.num * sizeof(int));
+		if (ret)
+			ret = -EFAULT;
 	}
 
+	/* If we have not had any EFAULT-like global errors then set the global
+	 * error to -ENOENT if necessary. */
+	if ((ret == 0) && (state.global_error == -ENOENT))
+		ret = -ENOENT;
+
 out:
+	kfree(err_array);
 	free_page_list(&pagelist);
 
 	return ret;
@@ -354,7 +423,11 @@ static long privcmd_ioctl(struct file *file,
 		break;
 
 	case IOCTL_PRIVCMD_MMAPBATCH:
-		ret = privcmd_ioctl_mmap_batch(udata);
+		ret = privcmd_ioctl_mmap_batch(udata, 1);
+		break;
+
+	case IOCTL_PRIVCMD_MMAPBATCH_V2:
+		ret = privcmd_ioctl_mmap_batch(udata, 2);
 		break;
 
 	default:
@@ -380,10 +453,6 @@ static struct vm_operations_struct privcmd_vm_ops = {
 
 static int privcmd_mmap(struct file *file, struct vm_area_struct *vma)
 {
-	/* Unsupported for auto-translate guests. */
-	if (xen_feature(XENFEAT_auto_translated_physmap))
-		return -ENOSYS;
-
 	/* DONTCOPY is essential for Xen because copy_page_range doesn't know
 	 * how to recreate these mappings */
 	vma->vm_flags |= VM_RESERVED | VM_IO | VM_DONTCOPY | VM_PFNMAP;