| Message ID | 20180508212405.15297-5-rgoldwyn@suse.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, May 9, 2018 at 12:24 AM, Goldwyn Rodrigues <rgoldwyn@suse.de> wrote: > From: Goldwyn Rodrigues <rgoldwyn@suse.com> > > This will preserve the holes and will clone(), if available. > > Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Only please mention in commit message that it changes behavoir slightly for a very large file (clone in chunks). I see no problem with this change. And please test with xfstest overlay/001 with copies up a large sparse file. test time should drop from ~30s to 0s. If you like I can test that one for you. I believe there are also generic copy_file_range tests in xfstests. Thanks, Amir.
On 05/09/2018 12:50 AM, Amir Goldstein wrote: > On Wed, May 9, 2018 at 12:24 AM, Goldwyn Rodrigues <rgoldwyn@suse.de> wrote: >> From: Goldwyn Rodrigues <rgoldwyn@suse.com> >> >> This will preserve the holes and will clone(), if available. >> >> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> > Reviewed-by: Amir Goldstein <amir73il@gmail.com> > > Only please mention in commit message that it changes behavoir > slightly for a very large file (clone in chunks). Change behavior? Only it will have holes. It will still respect length. Actually, I found a bug when it would not respect length if offset is father than length which I have fixed. > I see no problem with this change. > > And please test with xfstest overlay/001 with copies up a large > sparse file. test time should drop from ~30s to 0s. Yup, it passes in 1s on my VM :) > If you like I can test that one for you. > I believe there are also generic copy_file_range tests in xfstests. > Thanks for the review
On Wed, May 9, 2018 at 10:13 PM, Goldwyn Rodrigues <rgoldwyn@suse.de> wrote: > > > On 05/09/2018 12:50 AM, Amir Goldstein wrote: >> On Wed, May 9, 2018 at 12:24 AM, Goldwyn Rodrigues <rgoldwyn@suse.de> wrote: >>> From: Goldwyn Rodrigues <rgoldwyn@suse.com> >>> >>> This will preserve the holes and will clone(), if available. >>> >>> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> >> Reviewed-by: Amir Goldstein <amir73il@gmail.com> >> >> Only please mention in commit message that it changes behavoir >> slightly for a very large file (clone in chunks). > > Change behavior? Only it will have holes. It will still respect length. > Actually, I found a bug when it would not respect length if offset is > father than length which I have fixed. What I meant is the change of behavior for when underlying fs supports clone. Your patch changes the behavior for a very large file from single call to vfs_clone_file_range() on entire length to several calls in a loop. Nevermind. It's too insignificant for anyone to care. If overlayfs ever supports NFS as upper layer, we may want to rethink this. Thanks, Amir.
diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c index 8bede0742619..1f89380873ce 100644 --- a/fs/overlayfs/copy_up.c +++ b/fs/overlayfs/copy_up.c @@ -138,8 +138,7 @@ static int ovl_copy_up_data(struct path *old, struct path *new, loff_t len) { struct file *old_file; struct file *new_file; - loff_t old_pos = 0; - loff_t new_pos = 0; + loff_t pos = 0; int error = 0; if (len == 0) @@ -155,38 +154,27 @@ static int ovl_copy_up_data(struct path *old, struct path *new, loff_t len) goto out_fput; } - /* Try to use clone_file_range to clone up within the same fs */ - error = vfs_clone_file_range(old_file, 0, new_file, 0, len); - if (!error) - goto out; - /* Couldn't clone, so now we try to copy the data */ - error = 0; - - /* FIXME: copy up sparse files efficiently */ - while (len) { + while (pos < len) { size_t this_len = OVL_COPY_UP_CHUNK_SIZE; long bytes; - if (len < this_len) - this_len = len; + if (len - pos < this_len) + this_len = len - pos; if (signal_pending_state(TASK_KILLABLE, current)) { error = -EINTR; break; } - bytes = do_splice_direct(old_file, &old_pos, - new_file, &new_pos, - this_len, SPLICE_F_MOVE); + bytes = do_copy_file_range(old_file, pos, + new_file, pos, + this_len, 0, SPLICE_F_MOVE); if (bytes <= 0) { error = bytes; break; } - WARN_ON(old_pos != new_pos); - - len -= bytes; + pos += bytes; } -out: if (!error) error = vfs_fsync(new_file, 0); fput(new_file); diff --git a/fs/read_write.c b/fs/read_write.c index 5df9d6e8ebee..57b5b74c982a 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1542,7 +1542,7 @@ COMPAT_SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, } #endif -static ssize_t do_copy_file_range(struct file *file_in, loff_t pos_in, +ssize_t do_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, unsigned int splice_flags) @@ -1631,6 +1631,7 @@ static ssize_t do_copy_file_range(struct file *file_in, loff_t pos_in, out: return total ? total : ret; } +EXPORT_SYMBOL(do_copy_file_range); /* * copy_file_range() differs from regular file read and write in that it diff --git a/include/linux/fs.h b/include/linux/fs.h index 760d8da1b6c7..d5349b17fa10 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1799,6 +1799,9 @@ extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *); extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *); extern ssize_t vfs_readv(struct file *, const struct iovec __user *, unsigned long, loff_t *, rwf_t); +extern ssize_t do_copy_file_range(struct file *, loff_t , struct file *, + loff_t , size_t, unsigned int, + unsigned int); extern ssize_t vfs_copy_file_range(struct file *, loff_t , struct file *, loff_t, size_t, unsigned int); extern int vfs_clone_file_prep_inodes(struct inode *inode_in, loff_t pos_in,