Merge branch 'work.splice' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull splice updates from Al Viro:
 "These actually missed the last cycle; the branch itself is from last
  December"

* 'work.splice' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  make nr_pages calculation in default_file_splice_read() a bit less ugly
  splice/tee/vmsplice: validate flags
  splice_pipe_desc: kill ->flags
  remove spd_release_page()

fs/splice.c

@@ -247,11 +247,6 @@ ssize_t add_to_pipe(struct pipe_inode_info *pipe, struct pipe_buffer *buf)
 }
 EXPORT_SYMBOL(add_to_pipe);
 
-void spd_release_page(struct splice_pipe_desc *spd, unsigned int i)
-{
-	put_page(spd->pages[i]);
-}
-
 /*
  * Check if we need to grow the arrays holding pages and partial page
  * descriptions.
@@ -393,7 +388,7 @@ static ssize_t default_file_splice_read(struct file *in, loff_t *ppos,
 	struct iov_iter to;
 	struct page **pages;
 	unsigned int nr_pages;
-	size_t offset, dummy, copied = 0;
+	size_t offset, base, copied = 0;
 	ssize_t res;
 	int i;
 
@@ -408,12 +403,11 @@ static ssize_t default_file_splice_read(struct file *in, loff_t *ppos,
 
 	iov_iter_pipe(&to, ITER_PIPE | READ, pipe, len + offset);
 
-	res = iov_iter_get_pages_alloc(&to, &pages, len + offset, &dummy);
+	res = iov_iter_get_pages_alloc(&to, &pages, len + offset, &base);
 	if (res <= 0)
 		return -ENOMEM;
 
-	BUG_ON(dummy);
-	nr_pages = DIV_ROUND_UP(res, PAGE_SIZE);
+	nr_pages = DIV_ROUND_UP(res + base, PAGE_SIZE);
 
 	vec = __vec;
 	if (nr_pages > PIPE_DEF_BUFFERS) {
@@ -1359,6 +1353,8 @@ SYSCALL_DEFINE4(vmsplice, int, fd, const struct iovec __user *, iov,
 	struct fd f;
 	long error;
 
+	if (unlikely(flags & ~SPLICE_F_ALL))
+		return -EINVAL;
 	if (unlikely(nr_segs > UIO_MAXIOV))
 		return -EINVAL;
 	else if (unlikely(!nr_segs))
@@ -1409,6 +1405,9 @@ SYSCALL_DEFINE6(splice, int, fd_in, loff_t __user *, off_in,
 	if (unlikely(!len))
 		return 0;
 
+	if (unlikely(flags & ~SPLICE_F_ALL))
+		return -EINVAL;
+
 	error = -EBADF;
 	in = fdget(fd_in);
 	if (in.file) {
@@ -1737,6 +1736,9 @@ SYSCALL_DEFINE4(tee, int, fdin, int, fdout, size_t, len, unsigned int, flags)
 	struct fd in;
 	int error;
 
+	if (unlikely(flags & ~SPLICE_F_ALL))
+		return -EINVAL;
+
 	if (unlikely(!len))
 		return 0;
 

include/linux/splice.h

@@ -20,6 +20,8 @@
 #define SPLICE_F_MORE	(0x04)	/* expect more data */
 #define SPLICE_F_GIFT	(0x08)	/* pages passed in are a gift */
 
+#define SPLICE_F_ALL (SPLICE_F_MOVE|SPLICE_F_NONBLOCK|SPLICE_F_MORE|SPLICE_F_GIFT)
+
 /*
  * Passed to the actors
  */
@@ -55,7 +57,6 @@ struct splice_pipe_desc {
 	struct partial_page *partial;	/* pages[] may not be contig */
 	int nr_pages;			/* number of populated pages in map */
 	unsigned int nr_pages_max;	/* pages[] & partial[] arrays size */
-	unsigned int flags;		/* splice flags */
 	const struct pipe_buf_operations *ops;/* ops associated with output pipe */
 	void (*spd_release)(struct splice_pipe_desc *, unsigned int);
 };
@@ -82,7 +83,6 @@ extern ssize_t splice_direct_to_actor(struct file *, struct splice_desc *,
  */
 extern int splice_grow_spd(const struct pipe_inode_info *, struct splice_pipe_desc *);
 extern void splice_shrink_spd(struct splice_pipe_desc *);
-extern void spd_release_page(struct splice_pipe_desc *, unsigned int);
 
 extern const struct pipe_buf_operations page_cache_pipe_buf_ops;
 extern const struct pipe_buf_operations default_pipe_buf_ops;

kernel/relay.c

@@ -1212,7 +1212,6 @@ static ssize_t subbuf_splice_actor(struct file *in,
 		.nr_pages = 0,
 		.nr_pages_max = PIPE_DEF_BUFFERS,
 		.partial = partial,
-		.flags = flags,
 		.ops = &relay_pipe_buf_ops,
 		.spd_release = relay_page_release,
 	};

kernel/trace/trace.c

@@ -5530,7 +5530,6 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
 		.partial	= partial_def,
 		.nr_pages	= 0, /* This gets updated below. */
 		.nr_pages_max	= PIPE_DEF_BUFFERS,
-		.flags		= flags,
 		.ops		= &tracing_pipe_buf_ops,
 		.spd_release	= tracing_spd_release_pipe,
 	};
@@ -6428,7 +6427,6 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
 		.pages		= pages_def,
 		.partial	= partial_def,
 		.nr_pages_max	= PIPE_DEF_BUFFERS,
-		.flags		= flags,
 		.ops		= &buffer_pipe_buf_ops,
 		.spd_release	= buffer_spd_release,
 	};

net/core/skbuff.c

@@ -1982,7 +1982,6 @@ int skb_splice_bits(struct sk_buff *skb, struct sock *sk, unsigned int offset,
 		.pages = pages,
 		.partial = partial,
 		.nr_pages_max = MAX_SKB_FRAGS,
-		.flags = flags,
 		.ops = &nosteal_pipe_buf_ops,
 		.spd_release = sock_spd_release,
 	};