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> --- 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 -- 2.21.0
