In preparation of calling do_splice_direct() without file_start_write()
held, create a new helper splice_file_range(), to be called from context
of ->copy_file_range() methods instead of do_splice_direct().
Currently, the only difference is that splice_file_range() does not take
flags argument and that it asserts that file_start_write() is held, but
we factor out a common helper do_splice_direct_actor() that will be used
later.
Use the new helper from __ceph_copy_file_range(), that was incorrectly
passing to do_splice_direct() the copy flags argument as splice flags.
The value of copy flags in ceph is always 0, so it is a smenatic bug fix.
Move the declaration of both helpers to linux/splice.h.
Reviewed-by: Jan Kara <jack@xxxxxxx>
Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx>
---
fs/ceph/file.c | 9 +++---
fs/read_write.c | 6 ++--
fs/splice.c | 71 ++++++++++++++++++++++++++++++------------
include/linux/fs.h | 2 --
include/linux/splice.h | 13 +++++---
5 files changed, 66 insertions(+), 35 deletions(-)
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 3b5aae29e944..f11de6e1f1c1 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -12,6 +12,7 @@
#include <linux/falloc.h>
#include <linux/iversion.h>
#include <linux/ktime.h>
+#include <linux/splice.h>
#include "super.h"
#include "mds_client.h"
@@ -3010,8 +3011,8 @@ static ssize_t __ceph_copy_file_range(struct file *src_file, loff_t src_off,
* {read,write}_iter, which will get caps again.
*/
put_rd_wr_caps(src_ci, src_got, dst_ci, dst_got);
- ret = do_splice_direct(src_file, &src_off, dst_file,
- &dst_off, src_objlen, flags);
+ ret = splice_file_range(src_file, &src_off, dst_file, &dst_off,
+ src_objlen);
/* Abort on short copies or on error */
if (ret < (long)src_objlen) {
doutc(cl, "Failed partial copy (%zd)\n", ret);
@@ -3065,8 +3066,8 @@ static ssize_t __ceph_copy_file_range(struct file *src_file, loff_t src_off,
*/
if (len && (len < src_ci->i_layout.object_size)) {
doutc(cl, "Final partial copy of %zu bytes\n", len);
- bytes = do_splice_direct(src_file, &src_off, dst_file,
- &dst_off, len, flags);
+ bytes = splice_file_range(src_file, &src_off, dst_file,
+ &dst_off, len);
if (bytes > 0)
ret += bytes;
else
diff --git a/fs/read_write.c b/fs/read_write.c
index f791555fa246..642c7ce1ced1 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1423,10 +1423,8 @@ ssize_t generic_copy_file_range(struct file *file_in, loff_t pos_in,
struct file *file_out, loff_t pos_out,
size_t len, unsigned int flags)
{
- lockdep_assert(file_write_started(file_out));
-
- return do_splice_direct(file_in, &pos_in, file_out, &pos_out,
- len > MAX_RW_COUNT ? MAX_RW_COUNT : len, 0);
+ return splice_file_range(file_in, &pos_in, file_out, &pos_out,
+ min_t(size_t, len, MAX_RW_COUNT));
}
EXPORT_SYMBOL(generic_copy_file_range);
diff --git a/fs/splice.c b/fs/splice.c
index 3fce5f6072dd..9007b2c8baa8 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -1170,25 +1170,10 @@ static void direct_file_splice_eof(struct splice_desc *sd)
file->f_op->splice_eof(file);
}
-/**
- * do_splice_direct - splices data directly between two files
- * @in: file to splice from
- * @ppos: input file offset
- * @out: file to splice to
- * @opos: output file offset
- * @len: number of bytes to splice
- * @flags: splice modifier flags
- *
- * Description:
- * For use by do_sendfile(). splice can easily emulate sendfile, but
- * doing it in the application would incur an extra system call
- * (splice in + splice out, as compared to just sendfile()). So this helper
- * can splice directly through a process-private pipe.
- *
- * Callers already called rw_verify_area() on the entire range.
- */
-long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
- loff_t *opos, size_t len, unsigned int flags)
+static long do_splice_direct_actor(struct file *in, loff_t *ppos,
+ struct file *out, loff_t *opos,
+ size_t len, unsigned int flags,
+ splice_direct_actor *actor)
{
struct splice_desc sd = {
.len = len,
@@ -1207,14 +1192,60 @@ long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
if (unlikely(out->f_flags & O_APPEND))
return -EINVAL;
- ret = splice_direct_to_actor(in, &sd, direct_splice_actor);
+ ret = splice_direct_to_actor(in, &sd, actor);
if (ret > 0)
*ppos = sd.pos;
return ret;
}
+/**
+ * do_splice_direct - splices data directly between two files
+ * @in: file to splice from
+ * @ppos: input file offset
+ * @out: file to splice to
+ * @opos: output file offset
+ * @len: number of bytes to splice
+ * @flags: splice modifier flags
+ *
+ * Description:
+ * For use by do_sendfile(). splice can easily emulate sendfile, but
+ * doing it in the application would incur an extra system call
+ * (splice in + splice out, as compared to just sendfile()). So this helper
+ * can splice directly through a process-private pipe.
+ *
+ * Callers already called rw_verify_area() on the entire range.
+ */
+long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
+ loff_t *opos, size_t len, unsigned int flags)
+{
+ return do_splice_direct_actor(in, ppos, out, opos, len, flags,
+ direct_splice_actor);
+}
EXPORT_SYMBOL(do_splice_direct);
+/**
+ * splice_file_range - splices data between two files for copy_file_range()
+ * @in: file to splice from
+ * @ppos: input file offset
+ * @out: file to splice to
+ * @opos: output file offset
+ * @len: number of bytes to splice
+ *
+ * Description:
+ * For use by generic_copy_file_range() and ->copy_file_range() methods.
+ *
+ * Callers already called rw_verify_area() on the entire range.
+ */
+long splice_file_range(struct file *in, loff_t *ppos, struct file *out,
+ loff_t *opos, size_t len)
+{
+ lockdep_assert(file_write_started(out));
+
+ return do_splice_direct_actor(in, ppos, out, opos, len, 0,
+ direct_splice_actor);
+}
+EXPORT_SYMBOL(splice_file_range);
+
static int wait_for_space(struct pipe_inode_info *pipe, unsigned flags)
{
for (;;) {
diff --git a/include/linux/fs.h b/include/linux/fs.h
index ae0e2fb7bcea..04422a0eccdd 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -3052,8 +3052,6 @@ ssize_t copy_splice_read(struct file *in, loff_t *ppos,
size_t len, unsigned int flags);
extern ssize_t iter_file_splice_write(struct pipe_inode_info *,
struct file *, loff_t *, size_t, unsigned int);
-extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
- loff_t *opos, size_t len, unsigned int flags);
extern void
diff --git a/include/linux/splice.h b/include/linux/splice.h
index 6c461573434d..49532d5dda52 100644
--- a/include/linux/splice.h
+++ b/include/linux/splice.h
@@ -80,11 +80,14 @@ extern ssize_t add_to_pipe(struct pipe_inode_info *,
long vfs_splice_read(struct file *in, loff_t *ppos,
struct pipe_inode_info *pipe, size_t len,
unsigned int flags);
-extern ssize_t splice_direct_to_actor(struct file *, struct splice_desc *,
- splice_direct_actor *);
-extern long do_splice(struct file *in, loff_t *off_in,
- struct file *out, loff_t *off_out,
- size_t len, unsigned int flags);
+ssize_t splice_direct_to_actor(struct file *file, struct splice_desc *sd,
+ splice_direct_actor *actor);
+long do_splice(struct file *in, loff_t *off_in, struct file *out,
+ loff_t *off_out, size_t len, unsigned int flags);
+long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
+ loff_t *opos, size_t len, unsigned int flags);
+long splice_file_range(struct file *in, loff_t *ppos, struct file *out,
+ loff_t *opos, size_t len);
extern long do_tee(struct file *in, struct file *out, size_t len,
unsigned int flags);
--
2.34.1
