X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=kernel%2Frelay.c;h=7de644cdec43590be390d3037206e5722aa46856;hb=b72e9ebe7efa5754aa53bbdb0040a2d6eeb34db3;hp=61134eb7a0c8a9b2d2e0557b33ff4fbd7ff96f31;hpb=4800be295c34268fd3211d49828bfaa6bf62867f;p=linux-2.6

diff --git a/kernel/relay.c b/kernel/relay.c
index 61134eb7a0..7de644cdec 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -37,40 +37,63 @@ static void relay_file_mmap_close(struct vm_area_struct *vma)
 }
 
 /*
- * nopage() vm_op implementation for relay file mapping.
+ * fault() vm_op implementation for relay file mapping.
  */
-static struct page *relay_buf_nopage(struct vm_area_struct *vma,
-				     unsigned long address,
-				     int *type)
+static int relay_buf_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
 	struct page *page;
 	struct rchan_buf *buf = vma->vm_private_data;
-	unsigned long offset = address - vma->vm_start;
+	pgoff_t pgoff = vmf->pgoff;
 
-	if (address > vma->vm_end)
-		return NOPAGE_SIGBUS; /* Disallow mremap */
 	if (!buf)
-		return NOPAGE_OOM;
+		return VM_FAULT_OOM;
 
-	page = vmalloc_to_page(buf->start + offset);
+	page = vmalloc_to_page(buf->start + (pgoff << PAGE_SHIFT));
 	if (!page)
-		return NOPAGE_OOM;
+		return VM_FAULT_SIGBUS;
 	get_page(page);
+	vmf->page = page;
 
-	if (type)
-		*type = VM_FAULT_MINOR;
-
-	return page;
+	return 0;
 }
 
 /*
  * vm_ops for relay file mappings.
  */
 static struct vm_operations_struct relay_file_mmap_ops = {
-	.nopage = relay_buf_nopage,
+	.fault = relay_buf_fault,
 	.close = relay_file_mmap_close,
 };
 
+/*
+ * allocate an array of pointers of struct page
+ */
+static struct page **relay_alloc_page_array(unsigned int n_pages)
+{
+	struct page **array;
+	size_t pa_size = n_pages * sizeof(struct page *);
+
+	if (pa_size > PAGE_SIZE) {
+		array = vmalloc(pa_size);
+		if (array)
+			memset(array, 0, pa_size);
+	} else {
+		array = kzalloc(pa_size, GFP_KERNEL);
+	}
+	return array;
+}
+
+/*
+ * free an array of pointers of struct page
+ */
+static void relay_free_page_array(struct page **array)
+{
+	if (is_vmalloc_addr(array))
+		vfree(array);
+	else
+		kfree(array);
+}
+
 /**
  *	relay_mmap_buf: - mmap channel buffer to process address space
  *	@buf: relay channel buffer
@@ -92,6 +115,7 @@ static int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma)
 		return -EINVAL;
 
 	vma->vm_ops = &relay_file_mmap_ops;
+	vma->vm_flags |= VM_DONTEXPAND;
 	vma->vm_private_data = buf;
 	buf->chan->cb->buf_mapped(buf, filp);
 
@@ -114,7 +138,7 @@ static void *relay_alloc_buf(struct rchan_buf *buf, size_t *size)
 	*size = PAGE_ALIGN(*size);
 	n_pages = *size >> PAGE_SHIFT;
 
-	buf->page_array = kcalloc(n_pages, sizeof(struct page *), GFP_KERNEL);
+	buf->page_array = relay_alloc_page_array(n_pages);
 	if (!buf->page_array)
 		return NULL;
 
@@ -135,7 +159,7 @@ static void *relay_alloc_buf(struct rchan_buf *buf, size_t *size)
 depopulate:
 	for (j = 0; j < i; j++)
 		__free_page(buf->page_array[j]);
-	kfree(buf->page_array);
+	relay_free_page_array(buf->page_array);
 	return NULL;
 }
 
@@ -194,7 +218,7 @@ static void relay_destroy_buf(struct rchan_buf *buf)
 		vunmap(buf->start);
 		for (i = 0; i < buf->page_count; i++)
 			__free_page(buf->page_array[i]);
-		kfree(buf->page_array);
+		relay_free_page_array(buf->page_array);
 	}
 	chan->buf[buf->cpu] = NULL;
 	kfree(buf->padding);
@@ -741,7 +765,7 @@ static int relay_file_open(struct inode *inode, struct file *filp)
 	kref_get(&buf->kref);
 	filp->private_data = buf;
 
-	return 0;
+	return nonseekable_open(inode, filp);
 }
 
 /**
@@ -1061,6 +1085,10 @@ static struct pipe_buf_operations relay_pipe_buf_ops = {
 	.get = generic_pipe_buf_get,
 };
 
+static void relay_page_release(struct splice_pipe_desc *spd, unsigned int i)
+{
+}
+
 /*
  *	subbuf_splice_actor - splice up to one subbuf's worth of data
  */
@@ -1071,7 +1099,7 @@ static int subbuf_splice_actor(struct file *in,
 			       unsigned int flags,
 			       int *nonpad_ret)
 {
-	unsigned int pidx, poff, total_len, subbuf_pages, ret;
+	unsigned int pidx, poff, total_len, subbuf_pages, nr_pages, ret;
 	struct rchan_buf *rbuf = in->private_data;
 	unsigned int subbuf_size = rbuf->chan->subbuf_size;
 	uint64_t pos = (uint64_t) *ppos;
@@ -1088,6 +1116,7 @@ static int subbuf_splice_actor(struct file *in,
 		.partial = partial,
 		.flags = flags,
 		.ops = &relay_pipe_buf_ops,
+		.spd_release = relay_page_release,
 	};
 
 	if (rbuf->subbufs_produced == rbuf->subbufs_consumed)
@@ -1102,8 +1131,9 @@ static int subbuf_splice_actor(struct file *in,
 	subbuf_pages = rbuf->chan->alloc_size >> PAGE_SHIFT;
 	pidx = (read_start / PAGE_SIZE) % subbuf_pages;
 	poff = read_start & ~PAGE_MASK;
+	nr_pages = min_t(unsigned int, subbuf_pages, PIPE_BUFFERS);
 
-	for (total_len = 0; spd.nr_pages < subbuf_pages; spd.nr_pages++) {
+	for (total_len = 0; spd.nr_pages < nr_pages; spd.nr_pages++) {
 		unsigned int this_len, this_end, private;
 		unsigned int cur_pos = read_start + total_len;
 
@@ -1161,7 +1191,7 @@ static ssize_t relay_file_splice_read(struct file *in,
 	ret = 0;
 	spliced = 0;
 
-	while (len) {
+	while (len && !spliced) {
 		ret = subbuf_splice_actor(in, ppos, pipe, len, flags, &nonpad_ret);
 		if (ret < 0)
 			break;