On 9/9/19 2:29 AM, Jianhong.Yin wrote: > 1. copy_range should be a simple wrapper for copy_file_range(2) > and nothing else. and there's already -t option for truncate. > so here we remove the truncate action in copy_range. > see: https://patchwork.kernel.org/comment/22863587/#1 > > 2. improve the default length value generation: > if -l option is omitted use the length that from src_offset to end > (src_file's size - src_offset) instead. > if src_offset is greater than file size, length is 0. > > 3. update manpage > > 4. rename var name from 'src, dst' to 'src_off, dst_off' > > and have confirmed that this change will not affect xfstests. > > Signed-off-by: Jianhong Yin <yin-jianhong@xxxxxxx> Reviewed-by: Eric Sandeen <sandeen@xxxxxxxxxx> > --- > io/copy_file_range.c | 40 ++++++++++++++-------------------------- > man/man8/xfs_io.8 | 12 ++++++------ > 2 files changed, 20 insertions(+), 32 deletions(-) > > diff --git a/io/copy_file_range.c b/io/copy_file_range.c > index b7b9fd88..c2105115 100644 > --- a/io/copy_file_range.c > +++ b/io/copy_file_range.c > @@ -36,12 +36,12 @@ copy_range_help(void) > * glibc buffered copy fallback. > */ > static loff_t > -copy_file_range_cmd(int fd, long long *src, long long *dst, size_t len) > +copy_file_range_cmd(int fd, long long *src_off, long long *dst_off, size_t len) > { > loff_t ret; > > do { > - ret = syscall(__NR_copy_file_range, fd, src, file->fd, dst, > + ret = syscall(__NR_copy_file_range, fd, src_off, file->fd, dst_off, > len, 0); > if (ret == -1) { > perror("copy_range"); > @@ -66,21 +66,13 @@ copy_src_filesize(int fd) > return st.st_size; > } > > -static int > -copy_dst_truncate(void) > -{ > - int ret = ftruncate(file->fd, 0); > - if (ret < 0) > - perror("ftruncate"); > - return ret; > -} > - > static int > copy_range_f(int argc, char **argv) > { > - long long src = 0; > - long long dst = 0; > + long long src_off = 0; > + long long dst_off = 0; > size_t len = 0; > + bool len_specified = false; > int opt; > int ret; > int fd; > @@ -93,15 +85,15 @@ copy_range_f(int argc, char **argv) > while ((opt = getopt(argc, argv, "s:d:l:f:")) != -1) { > switch (opt) { > case 's': > - src = cvtnum(fsblocksize, fssectsize, optarg); > - if (src < 0) { > + src_off = cvtnum(fsblocksize, fssectsize, optarg); > + if (src_off < 0) { > printf(_("invalid source offset -- %s\n"), optarg); > return 0; > } > break; > case 'd': > - dst = cvtnum(fsblocksize, fssectsize, optarg); > - if (dst < 0) { > + dst_off = cvtnum(fsblocksize, fssectsize, optarg); > + if (dst_off < 0) { > printf(_("invalid destination offset -- %s\n"), optarg); > return 0; > } > @@ -112,6 +104,7 @@ copy_range_f(int argc, char **argv) > printf(_("invalid length -- %s\n"), optarg); > return 0; > } > + len_specified = true; > break; > case 'f': > src_file_nr = atoi(argv[1]); > @@ -137,7 +130,7 @@ copy_range_f(int argc, char **argv) > fd = filetable[src_file_nr].fd; > } > > - if (src == 0 && dst == 0 && len == 0) { > + if (!len_specified) { > off64_t sz; > > sz = copy_src_filesize(fd); > @@ -145,16 +138,11 @@ copy_range_f(int argc, char **argv) > ret = 1; > goto out; > } > - len = sz; > - > - ret = copy_dst_truncate(); > - if (ret < 0) { > - ret = 1; > - goto out; > - } > + if (sz > src_off) > + len = sz - src_off; > } > > - ret = copy_file_range_cmd(fd, &src, &dst, len); > + ret = copy_file_range_cmd(fd, &src_off, &dst_off, len); > out: > close(fd); > return ret; > diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8 > index 6e064bdd..61c35c8e 100644 > --- a/man/man8/xfs_io.8 > +++ b/man/man8/xfs_io.8 > @@ -669,13 +669,13 @@ The source must be specified either by path > or as another open file > .RB ( \-f ). > If > -.I src_file > -.IR src_offset , > -.IR dst_offset , > -and > .I length > -are omitted the contents of src_file will be copied to the beginning of the > -open file, overwriting any data already there. > +is not specified, this command copies data from > +.I src_offset > +to the end of > +.BI src_file > +into the dst_file at > +.IR dst_offset . > .RS 1.0i > .PD 0 > .TP 0.4i >
