VFS: rename do_splice_to/from to vfs_splice_* and export symbols

A stackable file system which uses vm_ops->fault, and does not implement
address_space_operations, cannot use generic_file_splice_read/write, but has
to implement ->splice_read/write itself.  These two helper functions are
very useful to such a module.

Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>

diff --git a/fs/splice.c b/fs/splice.c
index a54b3e3f10a716cb63ab56311745716a70086d0f..2ab3a3259af7858c233c63f97aaf6c1cd9a1c925 100644 (file)
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -888,8 +888,8 @@ 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 vfs_splice_from(struct pipe_inode_info *pipe, struct file *out,
+                    loff_t *ppos, size_t len, unsigned int flags)
 {
        int ret;
 
@@ -908,13 +908,14 @@ static long do_splice_from(struct pipe_inode_info *pipe, struct file *out,
 
        return out->f_op->splice_write(pipe, out, ppos, len, flags);
 }
+EXPORT_SYMBOL_GPL(vfs_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 vfs_splice_to(struct file *in, loff_t *ppos,
+                  struct pipe_inode_info *pipe, size_t len,
+                  unsigned int flags)
 {
        int ret;
 
@@ -930,6 +931,7 @@ static long do_splice_to(struct file *in, loff_t *ppos,
 
        return in->f_op->splice_read(in, ppos, pipe, len, flags);
 }
+EXPORT_SYMBOL_GPL(vfs_splice_to);
 
 /**
  * splice_direct_to_actor - splices data directly between two non-pipes
@@ -999,7 +1001,7 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd,
                size_t read_len;
                loff_t pos = sd->pos, prev_pos = pos;
 
-               ret = do_splice_to(in, &pos, pipe, len, flags);
+               ret = vfs_splice_to(in, &pos, pipe, len, flags);
                if (unlikely(ret <= 0))
                        goto out_release;
 
@@ -1058,7 +1060,7 @@ static int direct_splice_actor(struct pipe_inode_info *pipe,
 {
        struct file *file = sd->u.file;
 
-       return do_splice_from(pipe, file, &sd->pos, sd->total_len, sd->flags);
+       return vfs_splice_from(pipe, file, &sd->pos, sd->total_len, sd->flags);
 }
 
 /**
@@ -1132,7 +1134,7 @@ static long do_splice(struct file *in, loff_t __user *off_in,
                } else
                        off = &out->f_pos;
 
-               ret = do_splice_from(pipe, out, off, len, flags);
+               ret = vfs_splice_from(pipe, out, off, len, flags);
 
                if (off_out && copy_to_user(off_out, off, sizeof(loff_t)))
                        ret = -EFAULT;
@@ -1153,7 +1155,7 @@ static long do_splice(struct file *in, loff_t __user *off_in,
                } else
                        off = &in->f_pos;
 
-               ret = do_splice_to(in, off, pipe, len, flags);
+               ret = vfs_splice_to(in, off, pipe, len, flags);
 
                if (off_in && copy_to_user(off_in, off, sizeof(loff_t)))
                        ret = -EFAULT;

diff --git a/include/linux/splice.h b/include/linux/splice.h
index 528dcb93c2f21b08cad24fd56e3a6ae8e707dbc0..4b5727c169ebdd5a76533e43c2776f7e1fe4f2f7 100644 (file)
--- a/include/linux/splice.h
+++ b/include/linux/splice.h
@@ -70,5 +70,10 @@ extern ssize_t splice_to_pipe(struct pipe_inode_info *,
                              struct splice_pipe_desc *);
 extern ssize_t splice_direct_to_actor(struct file *, struct splice_desc *,
                                      splice_direct_actor *);
+extern long vfs_splice_from(struct pipe_inode_info *pipe, struct file *out,
+                           loff_t *ppos, size_t len, unsigned int flags);
+extern long vfs_splice_to(struct file *in, loff_t *ppos,
+                         struct pipe_inode_info *pipe, size_t len,
+                         unsigned int flags);
 
 #endif