From: Dave Chinner <david@fromorbit.com>
To: linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org
Cc: olga.kornievskaia@gmail.com, linux-nfs@vger.kernel.org,
linux-unionfs@vger.kernel.org, ceph-devel@vger.kernel.org,
linux-cifs@vger.kernel.org
Subject: [PATCH 02/11] vfs: introduce generic_copy_file_range()
Date: Mon, 3 Dec 2018 19:34:07 +1100 [thread overview]
Message-ID: <20181203083416.28978-3-david@fromorbit.com> (raw)
In-Reply-To: <20181203083416.28978-1-david@fromorbit.com>
From: Dave Chinner <dchinner@redhat.com>
Right now if vfs_copy_file_range() does not use any offload
mechanism, it falls back to calling do_splice_direct(). This fails
to do basic sanity checks on the files being copied. Before we
start adding this necessarily functionality to the fallback path,
separate it out into generic_copy_file_range().
generic_copy_file_range() has the same prototype as
->copy_file_range() so that filesystems can use it in their custom
->copy_file_range() method if they so choose.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
---
fs/read_write.c | 35 ++++++++++++++++++++++++++++++++---
include/linux/fs.h | 3 +++
2 files changed, 35 insertions(+), 3 deletions(-)
diff --git a/fs/read_write.c b/fs/read_write.c
index 09d1816cf3cf..50114694c98b 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1540,6 +1540,36 @@ COMPAT_SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd,
}
#endif
+/**
+ * generic_copy_file_range - copy data between two files
+ * @file_in: file structure to read from
+ * @pos_in: file offset to read from
+ * @file_out: file structure to write data to
+ * @pos_out: file offset to write data to
+ * @len: amount of data to copy
+ * @flags: copy flags
+ *
+ * This is a generic filesystem helper to copy data from one file to another.
+ * It has no constraints on the source or destination file owners - the files
+ * can belong to different superblocks and different filesystem types. Short
+ * copies are allowed.
+ *
+ * This should be called from the @file_out filesystem, as per the
+ * ->copy_file_range() method.
+ *
+ * Returns the number of bytes copied or a negative error indicating the
+ * failure.
+ */
+
+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)
+{
+ return do_splice_direct(file_in, &pos_in, file_out, &pos_out,
+ len > MAX_RW_COUNT ? MAX_RW_COUNT : len, 0);
+}
+EXPORT_SYMBOL(generic_copy_file_range);
+
/*
* copy_file_range() differs from regular file read and write in that it
* specifically allows return partial success. When it does so is up to
@@ -1611,9 +1641,8 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in,
goto done;
}
- ret = do_splice_direct(file_in, &pos_in, file_out, &pos_out,
- len > MAX_RW_COUNT ? MAX_RW_COUNT : len, 0);
-
+ ret = generic_copy_file_range(file_in, &pos_in, file_out, &pos_out,
+ len, flags);
done:
if (ret > 0) {
fsnotify_access(file_in);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index c95c0807471f..a4478764cf63 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1874,6 +1874,9 @@ extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
unsigned long, loff_t *, rwf_t);
extern ssize_t vfs_copy_file_range(struct file *, loff_t , struct file *,
loff_t, size_t, unsigned int);
+extern 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);
extern int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in,
struct file *file_out, loff_t pos_out,
loff_t *count,
--
2.19.1
next prev parent reply other threads:[~2018-12-03 8:34 UTC|newest]
Thread overview: 83+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-12-03 8:34 [PATCH 0/11] fs: fixes for major copy_file_range() issues Dave Chinner
2018-12-03 8:34 ` [PATCH 01/11] vfs: copy_file_range source range over EOF should fail Dave Chinner
2018-12-03 12:46 ` Amir Goldstein
2018-12-04 15:13 ` Christoph Hellwig
2018-12-04 21:29 ` Dave Chinner
2018-12-04 21:47 ` Olga Kornievskaia
2018-12-04 22:31 ` Dave Chinner
2018-12-05 16:51 ` J. Bruce Fields
2019-05-20 9:10 ` Amir Goldstein
2019-05-20 13:12 ` Olga Kornievskaia
2019-05-20 13:36 ` Amir Goldstein
2019-05-20 13:58 ` Olga Kornievskaia
2019-05-20 14:02 ` Amir Goldstein
2018-12-05 14:12 ` Christoph Hellwig
2018-12-05 21:08 ` Dave Chinner
2018-12-05 21:30 ` Christoph Hellwig
2018-12-03 8:34 ` Dave Chinner [this message]
2018-12-03 10:03 ` [PATCH 02/11] vfs: introduce generic_copy_file_range() Amir Goldstein
2018-12-03 23:00 ` Dave Chinner
2018-12-04 15:14 ` Christoph Hellwig
2018-12-03 8:34 ` [PATCH 03/11] vfs: no fallback for ->copy_file_range Dave Chinner
2018-12-03 10:22 ` Amir Goldstein
2018-12-03 23:02 ` Dave Chinner
2018-12-06 4:16 ` Amir Goldstein
2018-12-06 21:30 ` Dave Chinner
2018-12-07 5:38 ` Amir Goldstein
2018-12-03 18:23 ` Anna Schumaker
2018-12-04 15:16 ` Christoph Hellwig
2018-12-03 8:34 ` [PATCH 04/11] vfs: add missing checks to copy_file_range Dave Chinner
2018-12-03 12:42 ` Amir Goldstein
2018-12-03 19:04 ` Darrick J. Wong
2018-12-03 21:33 ` Olga Kornievskaia
2018-12-03 23:04 ` Dave Chinner
2018-12-04 15:18 ` Christoph Hellwig
2018-12-12 11:31 ` Luis Henriques
2018-12-12 16:42 ` Darrick J. Wong
2018-12-12 18:55 ` Olga Kornievskaia
2018-12-12 19:42 ` Matthew Wilcox
2018-12-12 20:22 ` Olga Kornievskaia
2018-12-13 10:29 ` Luis Henriques
2018-12-03 8:34 ` [PATCH 05/11] vfs: use inode_permission in copy_file_range() Dave Chinner
2018-12-03 12:47 ` Amir Goldstein
2018-12-03 18:18 ` Darrick J. Wong
2018-12-03 23:55 ` Dave Chinner
2018-12-05 17:28 ` J. Bruce Fields
2018-12-03 18:53 ` Eric Biggers
2018-12-04 15:19 ` Christoph Hellwig
2018-12-03 8:34 ` [PATCH 06/11] vfs: copy_file_range needs to strip setuid bits Dave Chinner
2018-12-03 12:51 ` Amir Goldstein
2018-12-04 15:21 ` Christoph Hellwig
2018-12-03 8:34 ` [PATCH 07/11] vfs: copy_file_range should update file timestamps Dave Chinner
2018-12-03 10:47 ` Amir Goldstein
2018-12-03 17:33 ` Olga Kornievskaia
2018-12-03 18:22 ` Darrick J. Wong
2018-12-03 23:19 ` Dave Chinner
2018-12-04 15:24 ` Christoph Hellwig
2018-12-03 8:34 ` [PATCH 08/11] vfs: push EXDEV check down into ->remap_file_range Dave Chinner
2018-12-03 11:04 ` Amir Goldstein
2018-12-03 19:11 ` Darrick J. Wong
2018-12-03 23:37 ` Dave Chinner
2018-12-03 23:58 ` Darrick J. Wong
2018-12-04 9:17 ` Amir Goldstein
2018-12-03 23:34 ` Dave Chinner
2018-12-03 18:24 ` Darrick J. Wong
2018-12-04 8:18 ` Olga Kornievskaia
2018-12-03 8:34 ` [PATCH 09/11] vfs: push copy_file_ranges -EXDEV checks down Dave Chinner
2018-12-03 12:36 ` Amir Goldstein
2018-12-03 17:58 ` Olga Kornievskaia
2018-12-03 18:53 ` Anna Schumaker
2018-12-03 19:27 ` Olga Kornievskaia
2018-12-03 23:40 ` Dave Chinner
2018-12-04 15:43 ` Christoph Hellwig
2018-12-04 22:18 ` Dave Chinner
2018-12-04 23:33 ` Olga Kornievskaia
2018-12-05 14:09 ` Christoph Hellwig
2018-12-05 17:01 ` Olga Kornievskaia
2018-12-03 8:34 ` [PATCH 10/11] vfs: allow generic_copy_file_range to copy across devices Dave Chinner
2018-12-03 12:54 ` Amir Goldstein
2018-12-03 8:34 ` [PATCH 11/11] ovl: allow cross-device copy_file_range calls Dave Chinner
2018-12-03 12:55 ` Amir Goldstein
2018-12-03 8:39 ` [PATCH 12/11] man-pages: copy_file_range updates Dave Chinner
2018-12-03 13:05 ` Amir Goldstein
2019-05-21 5:52 ` Amir Goldstein
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