From 79c14141a487211d1bb7840d3f607766f6115dd2 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Tue, 27 Jan 2015 13:13:12 -0800 Subject: [PATCH] vhost/scsi: Convert completion path to use copy_to_iter Required for ANY_LAYOUT support when the incoming virtio-scsi response header + fixed size sense buffer payload may span more than a single iovec entry. This changes existing code to save cmd->tvc_resp_iov instead of the first single iovec base pointer from &vq->iov[out]. Cc: Michael S. Tsirkin Cc: Paolo Bonzini Cc: Al Viro Signed-off-by: Nicholas Bellinger --- drivers/vhost/scsi.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c index 01c01cb3933f..29dfdf66bbc5 100644 --- a/drivers/vhost/scsi.c +++ b/drivers/vhost/scsi.c @@ -72,6 +72,8 @@ struct tcm_vhost_cmd { int tvc_vq_desc; /* virtio-scsi initiator task attribute */ int tvc_task_attr; + /* virtio-scsi response incoming iovecs */ + int tvc_in_iovs; /* virtio-scsi initiator data direction */ enum dma_data_direction tvc_data_direction; /* Expected data transfer length from virtio-scsi header */ @@ -87,8 +89,8 @@ struct tcm_vhost_cmd { struct scatterlist *tvc_sgl; struct scatterlist *tvc_prot_sgl; struct page **tvc_upages; - /* Pointer to response */ - struct virtio_scsi_cmd_resp __user *tvc_resp; + /* Pointer to response header iovec */ + struct iovec *tvc_resp_iov; /* Pointer to vhost_scsi for our device */ struct vhost_scsi *tvc_vhost; /* Pointer to vhost_virtqueue for the cmd */ @@ -682,6 +684,7 @@ static void vhost_scsi_complete_cmd_work(struct vhost_work *work) struct tcm_vhost_cmd *cmd; struct llist_node *llnode; struct se_cmd *se_cmd; + struct iov_iter iov_iter; int ret, vq; bitmap_zero(signal, VHOST_SCSI_MAX_VQ); @@ -703,8 +706,11 @@ static void vhost_scsi_complete_cmd_work(struct vhost_work *work) se_cmd->scsi_sense_length); memcpy(v_rsp.sense, cmd->tvc_sense_buf, se_cmd->scsi_sense_length); - ret = copy_to_user(cmd->tvc_resp, &v_rsp, sizeof(v_rsp)); - if (likely(ret == 0)) { + + iov_iter_init(&iov_iter, READ, cmd->tvc_resp_iov, + cmd->tvc_in_iovs, sizeof(v_rsp)); + ret = copy_to_iter(&v_rsp, sizeof(v_rsp), &iov_iter); + if (likely(ret == sizeof(v_rsp))) { struct vhost_scsi_virtqueue *q; vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0); q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq); @@ -1159,7 +1165,8 @@ vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq) cmd->tvc_vhost = vs; cmd->tvc_vq = vq; - cmd->tvc_resp = vq->iov[out].iov_base; + cmd->tvc_resp_iov = &vq->iov[out]; + cmd->tvc_in_iovs = in; pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n", cmd->tvc_cdb[0], cmd->tvc_lun); -- 2.20.1