Merge branch 'stable-3.2' into pandora-3.2

[pandora-kernel.git] / fs / splice.c

diff --git a/fs/splice.c b/fs/splice.c
index 014fcb4..d9ff2be 100644 (file)
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -554,6 +554,24 @@ static const struct pipe_buf_operations default_pipe_buf_ops = {
        .get = generic_pipe_buf_get,
 };
 
+static int generic_pipe_buf_nosteal(struct pipe_inode_info *pipe,
+                                   struct pipe_buffer *buf)
+{
+       return 1;
+}
+
+/* Pipe buffer operations for a socket and similar. */
+const struct pipe_buf_operations nosteal_pipe_buf_ops = {
+       .can_merge = 0,
+       .map = generic_pipe_buf_map,
+       .unmap = generic_pipe_buf_unmap,
+       .confirm = generic_pipe_buf_confirm,
+       .release = generic_pipe_buf_release,
+       .steal = generic_pipe_buf_nosteal,
+       .get = generic_pipe_buf_get,
+};
+EXPORT_SYMBOL(nosteal_pipe_buf_ops);
+
 static ssize_t kernel_readv(struct file *file, const struct iovec *vec,
                            unsigned long vlen, loff_t offset)
 {
@@ -697,8 +715,10 @@ static int pipe_to_sendpage(struct pipe_inode_info *pipe,
                return -EINVAL;
 
        more = (sd->flags & SPLICE_F_MORE) ? MSG_MORE : 0;
-       if (sd->len < sd->total_len)
+
+       if (sd->len < sd->total_len && pipe->nrbufs > 1)
                more |= MSG_SENDPAGE_NOTLAST;
+
        return file->f_op->sendpage(file, buf->page, buf->offset,
                                    sd->len, &pos, more);
 }
@@ -852,6 +872,13 @@ EXPORT_SYMBOL(splice_from_pipe_feed);
  */
 int splice_from_pipe_next(struct pipe_inode_info *pipe, struct splice_desc *sd)
 {
+       /*
+        * Check for signal early to make process killable when there are
+        * always buffers available
+        */
+       if (signal_pending(current))
+               return -ERESTARTSYS;
+
        while (!pipe->nrbufs) {
                if (!pipe->writers)
                        return 0;
@@ -930,6 +957,7 @@ ssize_t __splice_from_pipe(struct pipe_inode_info *pipe, struct splice_desc *sd,
 
        splice_from_pipe_begin(sd);
        do {
+               cond_resched();
                ret = splice_from_pipe_next(pipe, sd);
                if (ret > 0)
                        ret = splice_from_pipe_feed(pipe, sd, actor);
@@ -993,13 +1021,17 @@ generic_file_splice_write(struct pipe_inode_info *pipe, struct file *out,
        struct address_space *mapping = out->f_mapping;
        struct inode *inode = mapping->host;
        struct splice_desc sd = {
-               .total_len = len,
                .flags = flags,
-               .pos = *ppos,
                .u.file = out,
        };
        ssize_t ret;
 
+       ret = generic_write_checks(out, ppos, &len, S_ISBLK(inode->i_mode));
+       if (ret)
+               return ret;
+       sd.total_len = len;
+       sd.pos = *ppos;
+
        pipe_lock(pipe);
 
        splice_from_pipe_begin(&sd);
@@ -1092,8 +1124,8 @@ EXPORT_SYMBOL(generic_splice_sendpage);
 /*
  * Attempt to initiate a splice from pipe to file.
  */
-static long do_splice_from(struct pipe_inode_info *pipe, struct file *out,
-                          loff_t *ppos, size_t len, unsigned int flags)
+long do_splice_from(struct pipe_inode_info *pipe, struct file *out,
+                   loff_t *ppos, size_t len, unsigned int flags)
 {
        ssize_t (*splice_write)(struct pipe_inode_info *, struct file *,
                                loff_t *, size_t, unsigned int);
@@ -1116,13 +1148,14 @@ static long do_splice_from(struct pipe_inode_info *pipe, struct file *out,
 
        return splice_write(pipe, out, ppos, len, flags);
 }
+EXPORT_SYMBOL(do_splice_from);
 
 /*
  * Attempt to initiate a splice from a file to a pipe.
  */
-static long do_splice_to(struct file *in, loff_t *ppos,
-                        struct pipe_inode_info *pipe, size_t len,
-                        unsigned int flags)
+long do_splice_to(struct file *in, loff_t *ppos,
+                 struct pipe_inode_info *pipe, size_t len,
+                 unsigned int flags)
 {
        ssize_t (*splice_read)(struct file *, loff_t *,
                               struct pipe_inode_info *, size_t, unsigned int);
@@ -1142,6 +1175,7 @@ static long do_splice_to(struct file *in, loff_t *ppos,
 
        return splice_read(in, ppos, pipe, len, flags);
 }
+EXPORT_SYMBOL(do_splice_to);
 
 /**
  * splice_direct_to_actor - splices data directly between two non-pipes
@@ -1163,7 +1197,7 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd,
        long ret, bytes;
        umode_t i_mode;
        size_t len;
-       int i, flags;
+       int i, flags, more;
 
        /*
         * We require the input being a regular file, as we don't want to
@@ -1206,6 +1240,7 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd,
         * Don't block on output, we have to drain the direct pipe.
         */
        sd->flags &= ~SPLICE_F_NONBLOCK;
+       more = sd->flags & SPLICE_F_MORE;
 
        while (len) {
                size_t read_len;
@@ -1218,6 +1253,15 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd,
                read_len = ret;
                sd->total_len = read_len;
 
+               /*
+                * If more data is pending, set SPLICE_F_MORE
+                * If this is the last data and SPLICE_F_MORE was not set
+                * initially, clears it.
+                */
+               if (read_len < len)
+                       sd->flags |= SPLICE_F_MORE;
+               else if (!more)
+                       sd->flags &= ~SPLICE_F_MORE;
                /*
                 * NOTE: nonblocking mode only applies to the input. We
                 * must not do the output in nonblocking mode as then we