block: loop: introduce lo_discard() and lo_req_flush()
No behaviour change, just move the handling for REQ_DISCARD
and REQ_FLUSH in these two functions.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index d958901..018af27 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -417,6 +417,40 @@
return 0;
}
+static int lo_discard(struct loop_device *lo, struct request *rq, loff_t pos)
+{
+ /*
+ * We use punch hole to reclaim the free space used by the
+ * image a.k.a. discard. However we do not support discard if
+ * encryption is enabled, because it may give an attacker
+ * useful information.
+ */
+ struct file *file = lo->lo_backing_file;
+ int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
+ int ret;
+
+ if ((!file->f_op->fallocate) || lo->lo_encrypt_key_size) {
+ ret = -EOPNOTSUPP;
+ goto out;
+ }
+
+ ret = file->f_op->fallocate(file, mode, pos, blk_rq_bytes(rq));
+ if (unlikely(ret && ret != -EINVAL && ret != -EOPNOTSUPP))
+ ret = -EIO;
+ out:
+ return ret;
+}
+
+static int lo_req_flush(struct loop_device *lo, struct request *rq)
+{
+ struct file *file = lo->lo_backing_file;
+ int ret = vfs_fsync(file, 0);
+ if (unlikely(ret && ret != -EINVAL))
+ ret = -EIO;
+
+ return ret;
+}
+
static int do_req_filebacked(struct loop_device *lo, struct request *rq)
{
loff_t pos;
@@ -425,46 +459,19 @@
pos = ((loff_t) blk_rq_pos(rq) << 9) + lo->lo_offset;
if (rq->cmd_flags & REQ_WRITE) {
- struct file *file = lo->lo_backing_file;
- if (rq->cmd_flags & REQ_FLUSH) {
- ret = vfs_fsync(file, 0);
- if (unlikely(ret && ret != -EINVAL)) {
- ret = -EIO;
- goto out;
- }
- }
+ if (rq->cmd_flags & REQ_FLUSH)
+ ret = lo_req_flush(lo, rq);
- /*
- * We use punch hole to reclaim the free space used by the
- * image a.k.a. discard. However we do not support discard if
- * encryption is enabled, because it may give an attacker
- * useful information.
- */
if (rq->cmd_flags & REQ_DISCARD) {
- struct file *file = lo->lo_backing_file;
- int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
-
- if ((!file->f_op->fallocate) ||
- lo->lo_encrypt_key_size) {
- ret = -EOPNOTSUPP;
- goto out;
- }
- ret = file->f_op->fallocate(file, mode, pos,
- blk_rq_bytes(rq));
- if (unlikely(ret && ret != -EINVAL &&
- ret != -EOPNOTSUPP))
- ret = -EIO;
+ ret = lo_discard(lo, rq, pos);
goto out;
}
ret = lo_send(lo, rq, pos);
- if ((rq->cmd_flags & REQ_FUA) && !ret) {
- ret = vfs_fsync(file, 0);
- if (unlikely(ret && ret != -EINVAL))
- ret = -EIO;
- }
+ if ((rq->cmd_flags & REQ_FUA) && !ret)
+ ret = lo_req_flush(lo, rq);
} else
ret = lo_receive(lo, rq, lo->lo_blocksize, pos);
