[PATCH 09/11] vfs: push copy_file_ranges -EXDEV checks down

Dave Chinner
2018-12-03T08:34:42Z

From: Dave Chinner <dchinner@redhat.com>

We want to enable cross-filesystem copy_file_range functionality
where possible, so push the "same superblock only" checks down to
the individual filesystem callouts so they can make their own
decisions about cross-superblock copy offload.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
---
fs/ceph/file.c | 4 +++-
fs/cifs/cifsfs.c | 8 +++++++-
fs/fuse/file.c | 5 ++++-
fs/nfs/nfs4file.c | 16 ++++++++++------
fs/overlayfs/file.c | 10 +++++++++-
fs/read_write.c | 10 ++++------
6 files changed, 37 insertions(+), 16 deletions(-)

diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index cf29f0410dcb..eb876e19c1dc 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -1905,6 +1905,8 @@ static ssize_t __ceph_copy_file_range(struct file *src_file, loff_t src_off,

if (src_inode == dst_inode)
return -EINVAL;
+ if (src_inode->i_sb != dst_inode->i_sb)
+ return -EXDEV;
if (ceph_snap(dst_inode) != CEPH_NOSNAP)
return -EROFS;

@@ -2105,7 +2107,7 @@ static ssize_t ceph_copy_file_range(struct file *src_file, loff_t src_off,
ret = __ceph_copy_file_range(src_file, src_off, dst_file, dst_off,
len, flags);

- if (ret == -EOPNOTSUPP)
+ if (ret == -EOPNOTSUPP || ret == -EXDEV)
ret = generic_copy_file_range(src_file, src_off, dst_file,
dst_off, len, flags);
return ret;
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 5ef4baec6234..03e4b9eacbd1 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -1072,6 +1072,12 @@ ssize_t cifs_file_copychunk_range(unsigned int xid,
goto out;
}

+ if (src_inode->i_sb != target_inode->i_sb) {
+ rc = -EXDEV;
+ goto out;
+ }
+
+
if (!src_file->private_data || !dst_file->private_data) {
rc = -EBADF;
cifs_dbg(VFS, "missing cifsFileInfo on copy range src file\n");
@@ -1142,7 +1148,7 @@ static ssize_t cifs_copy_file_range(struct file *src_file, loff_t off,
len, flags);
free_xid(xid);

- if (rc == -EOPNOTSUPP)
+ if (rc == -EOPNOTSUPP || rc == -EXDEV)
rc = generic_copy_file_range(src_file, off, dst_file,
destoff, len, flags);
return rc;
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index b86fb0298739..0758f831a4eb 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -3053,6 +3053,9 @@ static ssize_t __fuse_copy_file_range(struct file *file_in, loff_t pos_in,
if (fc->no_copy_file_range)
return -EOPNOTSUPP;

+ if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb)
+ return -EXDEV;
+
inode_lock(inode_out);

if (fc->writeback_cache) {
@@ -3109,7 +3112,7 @@ static ssize_t fuse_copy_file_range(struct file *src_file, loff_t src_off,
ret = __fuse_copy_file_range(src_file, src_off, dst_file, dst_off,
len, flags);

- if (ret == -EOPNOTSUPP)
+ if (ret == -EOPNOTSUPP || ret == -EXDEV)
ret = generic_copy_file_range(src_file, src_off, dst_file,
dst_off, len, flags);
return ret;
diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
index d7766a6eb0f4..4783c0c1c49e 100644
--- a/fs/nfs/nfs4file.c
+++ b/fs/nfs/nfs4file.c
@@ -133,16 +133,20 @@ static ssize_t nfs4_copy_file_range(struct file *file_in, loff_t pos_in,
struct file *file_out, loff_t pos_out,
size_t count, unsigned int flags)
{
- ssize_t ret;
+ ssize_t ret = -EXDEV;

if (file_inode(file_in) == file_inode(file_out))
return -EINVAL;
-retry:
- ret = nfs42_proc_copy(file_in, pos_in, file_out, pos_out, count);
- if (ret == -EAGAIN)
- goto retry;

- if (ret == -EOPNOTSUPP)
+ /* only offload copy if superblock is the same */
+ if (file_inode(file_in)->i_sb == file_inode(file_out)->i_sb) {
+ do {
+ ret = nfs42_proc_copy(file_in, pos_in, file_out,
+ pos_out, count);
+ } while (ret == -EAGAIN);
+ }
+
+ if (ret == -EOPNOTSUPP || ret == -EXDEV)
ret = generic_copy_file_range(file_in, pos_in, file_out,
pos_out, count, flags);
return ret;
diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
index 68736e5d6a56..34fb0398d016 100644
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -443,6 +443,14 @@ static loff_t ovl_copyfile(struct file *file_in, loff_t pos_in,
const struct cred *old_cred;
loff_t ret;

+ /*
+ * Temporary. Cross device copy checks should be left to the copy file
+ * call on the real inodes, but existing behaviour checks the upper
+ * files only.
+ */
+ if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb)
+ return -EXDEV;
+
ret = ovl_real_fdget(file_out, &real_out);
if (ret)
return ret;
@@ -491,7 +499,7 @@ static ssize_t ovl_copy_file_range(struct file *file_in, loff_t pos_in,
ret = ovl_copyfile(file_in, pos_in, file_out, pos_out, len, flags,
OVL_COPY);

- if (ret == -EOPNOTSUPP)
+ if (ret == -EOPNOTSUPP || ret == -EXDEV)
ret = generic_copy_file_range(file_in, pos_in, file_out,
pos_out, len, flags);
return ret;
diff --git a/fs/read_write.c b/fs/read_write.c
index 174cf92eea1d..4e0666de0d69 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1565,6 +1565,10 @@ 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)
{
+ /* Temporary, do_splice_direct supports cross-sb copies */
+ if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb)
+ return -EXDEV;
+
return do_splice_direct(file_in, &pos_in, file_out, &pos_out,
len > MAX_RW_COUNT ? MAX_RW_COUNT : len, 0);
}
@@ -1611,17 +1615,11 @@ ssize_t vfs_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)
{
- struct inode *inode_in = file_inode(file_in);
- struct inode *inode_out = file_inode(file_out);
ssize_t ret;

if (flags != 0)
return -EINVAL;

- /* this could be relaxed once a method supports cross-fs copies */
- if (inode_in->i_sb != inode_out->i_sb)
- return -EXDEV;
-
ret = generic_copy_file_checks(file_in, pos_in, file_out, pos_out, &len,
flags);
if (ret < 0)
--
2.19.1