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>
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Родитель
3011201346
Коммит
cf655d9534
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@ -417,6 +417,40 @@ lo_receive(struct loop_device *lo, struct request *rq, int bsize, loff_t pos)
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return 0;
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return 0;
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}
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}
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static int lo_discard(struct loop_device *lo, struct request *rq, loff_t pos)
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{
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/*
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* We use punch hole to reclaim the free space used by the
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* image a.k.a. discard. However we do not support discard if
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* encryption is enabled, because it may give an attacker
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* useful information.
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*/
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struct file *file = lo->lo_backing_file;
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int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
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int ret;
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if ((!file->f_op->fallocate) || lo->lo_encrypt_key_size) {
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ret = -EOPNOTSUPP;
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goto out;
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}
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ret = file->f_op->fallocate(file, mode, pos, blk_rq_bytes(rq));
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if (unlikely(ret && ret != -EINVAL && ret != -EOPNOTSUPP))
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ret = -EIO;
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out:
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return ret;
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}
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static int lo_req_flush(struct loop_device *lo, struct request *rq)
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{
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struct file *file = lo->lo_backing_file;
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int ret = vfs_fsync(file, 0);
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if (unlikely(ret && ret != -EINVAL))
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ret = -EIO;
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return ret;
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}
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static int do_req_filebacked(struct loop_device *lo, struct request *rq)
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static int do_req_filebacked(struct loop_device *lo, struct request *rq)
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{
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{
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loff_t pos;
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loff_t pos;
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@ -425,46 +459,19 @@ static int do_req_filebacked(struct loop_device *lo, struct request *rq)
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pos = ((loff_t) blk_rq_pos(rq) << 9) + lo->lo_offset;
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pos = ((loff_t) blk_rq_pos(rq) << 9) + lo->lo_offset;
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if (rq->cmd_flags & REQ_WRITE) {
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if (rq->cmd_flags & REQ_WRITE) {
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struct file *file = lo->lo_backing_file;
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if (rq->cmd_flags & REQ_FLUSH) {
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if (rq->cmd_flags & REQ_FLUSH)
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ret = vfs_fsync(file, 0);
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ret = lo_req_flush(lo, rq);
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if (unlikely(ret && ret != -EINVAL)) {
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ret = -EIO;
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goto out;
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}
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}
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/*
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* We use punch hole to reclaim the free space used by the
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* image a.k.a. discard. However we do not support discard if
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* encryption is enabled, because it may give an attacker
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* useful information.
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*/
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if (rq->cmd_flags & REQ_DISCARD) {
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if (rq->cmd_flags & REQ_DISCARD) {
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struct file *file = lo->lo_backing_file;
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ret = lo_discard(lo, rq, pos);
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int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
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if ((!file->f_op->fallocate) ||
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lo->lo_encrypt_key_size) {
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ret = -EOPNOTSUPP;
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goto out;
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}
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ret = file->f_op->fallocate(file, mode, pos,
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blk_rq_bytes(rq));
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if (unlikely(ret && ret != -EINVAL &&
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ret != -EOPNOTSUPP))
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ret = -EIO;
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goto out;
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goto out;
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}
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}
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ret = lo_send(lo, rq, pos);
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ret = lo_send(lo, rq, pos);
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if ((rq->cmd_flags & REQ_FUA) && !ret) {
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if ((rq->cmd_flags & REQ_FUA) && !ret)
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ret = vfs_fsync(file, 0);
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ret = lo_req_flush(lo, rq);
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if (unlikely(ret && ret != -EINVAL))
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ret = -EIO;
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}
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} else
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} else
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ret = lo_receive(lo, rq, lo->lo_blocksize, pos);
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ret = lo_receive(lo, rq, lo->lo_blocksize, pos);
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