Fix bug with zone and zone skipping and io_limit

If you do:

dd if=/dev/zero of=/dev/shm/1M bs=1M count=1
fio --bs=4k --rw=write --filename=/dev/shm/1M --name=go \
--zoneskip=4k --zonesize=4k --io_limit=2M

then fio will exit after having performed 512KB of IO, instead
of the specified IO limit. This is a similar issue as was fixed
by commit ac002339c382 with rw sequencing - if we reach the
end of the file with a zone skip, wrap to the beginning.

Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/io_u.c b/io_u.c
index 583f1e39b2dd25a70c770b78c5f5519eda978925..9adc31bf04d1ce3cbaaaa2ddaa94e6b7f4dcb569 100644 (file)
--- a/io_u.c
+++ b/io_u.c
@@ -760,9 +760,17 @@ static int fill_io_u(struct thread_data *td, struct io_u *io_u)
         * See if it's time to switch to a new zone
         */
        if (td->zone_bytes >= td->o.zone_size && td->o.zone_skip) {
+               struct fio_file *f = io_u->file;
+
                td->zone_bytes = 0;
-               io_u->file->file_offset += td->o.zone_range + td->o.zone_skip;
-               io_u->file->last_pos = io_u->file->file_offset;
+               f->file_offset += td->o.zone_range + td->o.zone_skip;
+
+               /*
+                * Wrap from the beginning, if we exceed the file size
+                */
+               if (f->file_offset >= f->real_file_size)
+                       f->file_offset = f->real_file_size - f->file_offset;
+               f->last_pos = f->file_offset;
                td->io_skip_bytes += td->o.zone_skip;
        }