Fix backwards reads with --size smaller than the file size

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

diff --git a/io_u.c b/io_u.c
index 22701274cf3cc5aa2fe78d70a0d25171432281df..dcf7a40562531af0a55cd56ddb7d02a00527bdd6 100644 (file)
--- a/io_u.c
+++ b/io_u.c
@@ -362,8 +362,12 @@ static int get_next_seq_offset(struct thread_data *td, struct fio_file *f,
        if (f->last_pos[ddir] < f->real_file_size) {
                uint64_t pos;
 
-               if (f->last_pos[ddir] == f->file_offset && o->ddir_seq_add < 0)
-                       f->last_pos[ddir] = f->real_file_size;
+               if (f->last_pos[ddir] == f->file_offset && o->ddir_seq_add < 0) {
+                       if (f->real_file_size > f->io_size)
+                               f->last_pos[ddir] = f->io_size;
+                       else
+                               f->last_pos[ddir] = f->real_file_size;
+               }
 
                pos = f->last_pos[ddir] - f->file_offset;
                if (pos && o->ddir_seq_add) {
@@ -378,8 +382,14 @@ static int get_next_seq_offset(struct thread_data *td, struct fio_file *f,
                        if (pos >= f->real_file_size) {
                                if (o->ddir_seq_add > 0)
                                        pos = f->file_offset;
-                               else
-                                       pos = f->real_file_size + o->ddir_seq_add;
+                               else {
+                                       if (f->real_file_size > f->io_size)
+                                               pos = f->io_size;
+                                       else
+                                               pos = f->real_file_size;
+
+                                       pos += o->ddir_seq_add;
+                               }
                        }
                }