X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=blobdiff_plain;f=kernel%2Frelay.c;h=c7cf397fb92958bbcbd2772e13a8d4a4d9c00b6d;hp=824b91ac10f1f94f3990d5db6f7437d161f0f2a4;hb=254c8c2dbf0e06a560a5814eb90cb628adb2de66;hpb=8302294f43250dc337108c51882a6007f2b1e2e0

diff --git a/kernel/relay.c b/kernel/relay.c
index 824b91a..c7cf397 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -60,7 +60,7 @@ static int relay_buf_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 /*
  * vm_ops for relay file mappings.
  */
-static struct vm_operations_struct relay_file_mmap_ops = {
+static const struct vm_operations_struct relay_file_mmap_ops = {
 	.fault = relay_buf_fault,
 	.close = relay_file_mmap_close,
 };
@@ -539,7 +539,7 @@ static int __cpuinit relay_hotcpu_callback(struct notifier_block *nb,
 					"relay_hotcpu_callback: cpu %d buffer "
 					"creation failed\n", hotcpu);
 				mutex_unlock(&relay_channels_mutex);
-				return NOTIFY_BAD;
+				return notifier_from_errno(-ENOMEM);
 			}
 		}
 		mutex_unlock(&relay_channels_mutex);
@@ -795,13 +795,15 @@ void relay_subbufs_consumed(struct rchan *chan,
 	if (!chan)
 		return;
 
-	if (cpu >= NR_CPUS || !chan->buf[cpu])
+	if (cpu >= NR_CPUS || !chan->buf[cpu] ||
+					subbufs_consumed > chan->n_subbufs)
 		return;
 
 	buf = chan->buf[cpu];
-	buf->subbufs_consumed += subbufs_consumed;
-	if (buf->subbufs_consumed > buf->subbufs_produced)
+	if (subbufs_consumed > buf->subbufs_produced - buf->subbufs_consumed)
 		buf->subbufs_consumed = buf->subbufs_produced;
+	else
+		buf->subbufs_consumed += subbufs_consumed;
 }
 EXPORT_SYMBOL_GPL(relay_subbufs_consumed);
 
@@ -1196,7 +1198,7 @@ static void relay_pipe_buf_release(struct pipe_inode_info *pipe,
 	relay_consume_bytes(rbuf, buf->private);
 }
 
-static struct pipe_buf_operations relay_pipe_buf_ops = {
+static const struct pipe_buf_operations relay_pipe_buf_ops = {
 	.can_merge = 0,
 	.map = generic_pipe_buf_map,
 	.unmap = generic_pipe_buf_unmap,
@@ -1213,14 +1215,14 @@ 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
  */
-static int subbuf_splice_actor(struct file *in,
+static ssize_t subbuf_splice_actor(struct file *in,
 			       loff_t *ppos,
 			       struct pipe_inode_info *pipe,
 			       size_t len,
 			       unsigned int flags,
 			       int *nonpad_ret)
 {
-	unsigned int pidx, poff, total_len, subbuf_pages, nr_pages, ret;
+	unsigned int pidx, poff, total_len, subbuf_pages, nr_pages;
 	struct rchan_buf *rbuf = in->private_data;
 	unsigned int subbuf_size = rbuf->chan->subbuf_size;
 	uint64_t pos = (uint64_t) *ppos;
@@ -1229,8 +1231,8 @@ static int subbuf_splice_actor(struct file *in,
 	size_t read_subbuf = read_start / subbuf_size;
 	size_t padding = rbuf->padding[read_subbuf];
 	size_t nonpad_end = read_subbuf * subbuf_size + subbuf_size - padding;
-	struct page *pages[PIPE_BUFFERS];
-	struct partial_page partial[PIPE_BUFFERS];
+	struct page *pages[PIPE_DEF_BUFFERS];
+	struct partial_page partial[PIPE_DEF_BUFFERS];
 	struct splice_pipe_desc spd = {
 		.pages = pages,
 		.nr_pages = 0,
@@ -1239,9 +1241,12 @@ static int subbuf_splice_actor(struct file *in,
 		.ops = &relay_pipe_buf_ops,
 		.spd_release = relay_page_release,
 	};
+	ssize_t ret;
 
 	if (rbuf->subbufs_produced == rbuf->subbufs_consumed)
 		return 0;
+	if (splice_grow_spd(pipe, &spd))
+		return -ENOMEM;
 
 	/*
 	 * Adjust read len, if longer than what is available
@@ -1252,7 +1257,7 @@ 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);
+	nr_pages = min_t(unsigned int, subbuf_pages, pipe->buffers);
 
 	for (total_len = 0; spd.nr_pages < nr_pages; spd.nr_pages++) {
 		unsigned int this_len, this_end, private;
@@ -1286,16 +1291,19 @@ static int subbuf_splice_actor(struct file *in,
 		}
 	}
 
+	ret = 0;
 	if (!spd.nr_pages)
-		return 0;
+		goto out;
 
 	ret = *nonpad_ret = splice_to_pipe(pipe, &spd);
 	if (ret < 0 || ret < total_len)
-		return ret;
+		goto out;
 
         if (read_start + ret == nonpad_end)
                 ret += padding;
 
+out:
+	splice_shrink_spd(pipe, &spd);
         return ret;
 }