]> nv-tegra.nvidia Code Review - linux-2.6.git/blobdiff - fs/splice.c
splice: add SPLICE_F_NONBLOCK flag
[linux-2.6.git] / fs / splice.c
index 7c2bbf18d7a7c3622679bbf6e6a7f0bc0a78c7fa..6081cf7d2d1ba91c0b5d613904994cdd6876b8b9 100644 (file)
@@ -106,7 +106,7 @@ static struct pipe_buf_operations page_cache_pipe_buf_ops = {
 
 static ssize_t move_to_pipe(struct inode *inode, struct page **pages,
                            int nr_pages, unsigned long offset,
-                           unsigned long len)
+                           unsigned long len, unsigned int flags)
 {
        struct pipe_inode_info *info;
        int ret, do_wakeup, i;
@@ -159,6 +159,12 @@ static ssize_t move_to_pipe(struct inode *inode, struct page **pages,
                        break;
                }
 
+               if (flags & SPLICE_F_NONBLOCK) {
+                       if (!ret)
+                               ret = -EAGAIN;
+                       break;
+               }
+
                if (signal_pending(current)) {
                        if (!ret)
                                ret = -ERESTARTSYS;
@@ -191,7 +197,7 @@ static ssize_t move_to_pipe(struct inode *inode, struct page **pages,
 }
 
 static int __generic_file_splice_read(struct file *in, struct inode *pipe,
-                                     size_t len)
+                                     size_t len, unsigned int flags)
 {
        struct address_space *mapping = in->f_mapping;
        unsigned int offset, nr_pages;
@@ -279,7 +285,7 @@ static int __generic_file_splice_read(struct file *in, struct inode *pipe,
         * Now we splice them into the pipe..
         */
 splice_them:
-       return move_to_pipe(pipe, pages, i, offset, len);
+       return move_to_pipe(pipe, pages, i, offset, len, flags);
 }
 
 ssize_t generic_file_splice_read(struct file *in, struct inode *pipe,
@@ -291,7 +297,7 @@ ssize_t generic_file_splice_read(struct file *in, struct inode *pipe,
        ret = 0;
        spliced = 0;
        while (len) {
-               ret = __generic_file_splice_read(in, pipe, len);
+               ret = __generic_file_splice_read(in, pipe, len, flags);
 
                if (ret <= 0)
                        break;
@@ -299,6 +305,11 @@ ssize_t generic_file_splice_read(struct file *in, struct inode *pipe,
                in->f_pos += ret;
                len -= ret;
                spliced += ret;
+
+               if (!(flags & SPLICE_F_NONBLOCK))
+                       continue;
+               ret = -EAGAIN;
+               break;
        }
 
        if (spliced)
@@ -527,6 +538,12 @@ static ssize_t move_from_pipe(struct inode *inode, struct file *out,
                                break;
                }
 
+               if (flags & SPLICE_F_NONBLOCK) {
+                       if (!ret)
+                               ret = -EAGAIN;
+                       break;
+               }
+
                if (signal_pending(current)) {
                        if (!ret)
                                ret = -ERESTARTSYS;