If there's an overlapped command tag, cancel the command and respond
with RC_OVERLAPPED_TAG to host.
Signed-off-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>
---
drivers/usb/gadget/function/f_tcm.c | 123 +++++++++++++++++++++++++++-
drivers/usb/gadget/function/tcm.h | 5 ++
2 files changed, 127 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/gadget/function/f_tcm.c b/drivers/usb/gadget/function/f_tcm.c
index 3e04ce40a4a0..0c7a41568f40 100644
--- a/drivers/usb/gadget/function/f_tcm.c
+++ b/drivers/usb/gadget/function/f_tcm.c
@@ -685,12 +685,25 @@ static void uasp_status_data_cmpl(struct usb_ep *ep, struct usb_request *req)
break;
case UASP_QUEUE_COMMAND:
+ /*
+ * Overlapped command detected and cancelled.
+ * So send overlapped attempted status.
+ */
+ if (cmd->tmr_rsp == RC_OVERLAPPED_TAG &&
+ req->status == -ECONNRESET) {
+ uasp_send_tm_response(cmd);
+ return;
+ }
+
+ hash_del(&stream->node);
+
/*
* If no command submitted to target core here, just free the
* bitmap index. This is for the cases where f_tcm handles
* status response instead of the target core.
*/
- if (cmd->tmr_rsp != RC_RESPONSE_UNKNOWN) {
+ if (cmd->tmr_rsp != RC_OVERLAPPED_TAG &&
+ cmd->tmr_rsp != RC_RESPONSE_UNKNOWN) {
struct se_session *se_sess;
se_sess = fu->tpg->tpg_nexus->tvn_se_sess;
@@ -702,6 +715,7 @@ static void uasp_status_data_cmpl(struct usb_ep *ep, struct usb_request *req)
}
usb_ep_queue(fu->ep_cmd, cmd->req, GFP_ATOMIC);
+ complete(&stream->cmd_completion);
break;
default:
@@ -710,6 +724,7 @@ static void uasp_status_data_cmpl(struct usb_ep *ep, struct usb_request *req)
return;
cleanup:
+ hash_del(&stream->node);
transport_generic_free_cmd(&cmd->se_cmd, 0);
}
@@ -842,6 +857,8 @@ static void uasp_cmd_complete(struct usb_ep *ep, struct usb_request *req)
static int uasp_alloc_stream_res(struct f_uas *fu, struct uas_stream *stream)
{
+ init_completion(&stream->cmd_completion);
+
stream->req_in = usb_ep_alloc_request(fu->ep_in, GFP_KERNEL);
if (!stream->req_in)
goto out;
@@ -1046,6 +1063,9 @@ static void usbg_data_write_cmpl(struct usb_ep *ep, struct usb_request *req)
cmd->state = UASP_QUEUE_COMMAND;
if (req->status == -ESHUTDOWN) {
+ struct uas_stream *stream = &cmd->fu->stream[se_cmd->map_tag];
+
+ hash_del(&stream->node);
target_put_sess_cmd(se_cmd);
transport_generic_free_cmd(&cmd->se_cmd, 0);
return;
@@ -1069,6 +1089,14 @@ static void usbg_data_write_cmpl(struct usb_ep *ep, struct usb_request *req)
cleanup:
target_put_sess_cmd(se_cmd);
+
+ /* Command was aborted due to overlapped tag */
+ if (cmd->state == UASP_QUEUE_COMMAND &&
+ cmd->tmr_rsp == RC_OVERLAPPED_TAG) {
+ uasp_send_tm_response(cmd);
+ return;
+ }
+
transport_send_check_condition_and_sense(se_cmd,
TCM_CHECK_CONDITION_ABORT_CMD, 0);
}
@@ -1137,6 +1165,8 @@ static int usbg_send_read_response(struct se_cmd *se_cmd)
return uasp_send_read_response(cmd);
}
+static void usbg_aborted_task(struct se_cmd *se_cmd);
+
static void usbg_submit_tmr(struct usbg_cmd *cmd)
{
struct se_session *se_sess;
@@ -1214,6 +1244,74 @@ static void usbg_cmd_work(struct work_struct *work)
return;
skip:
+ if (cmd->tmr_rsp == RC_OVERLAPPED_TAG) {
+ struct f_uas *fu = cmd->fu;
+ struct se_session *se_sess;
+ struct uas_stream *stream = NULL;
+ struct hlist_node *tmp;
+ struct usbg_cmd *active_cmd = NULL;
+
+ se_sess = cmd->fu->tpg->tpg_nexus->tvn_se_sess;
+
+ hash_for_each_possible_safe(fu->stream_hash, stream, tmp, node, cmd->tag) {
+ int i = stream - &fu->stream[0];
+
+ active_cmd = &((struct usbg_cmd *)se_sess->sess_cmd_map)[i];
+ if (active_cmd->tag == cmd->tag)
+ break;
+ }
+
+ /* Sanity check */
+ if (!stream || (active_cmd && active_cmd->tag != cmd->tag)) {
+ usbg_submit_command(cmd->fu, cmd->req);
+ return;
+ }
+
+ reinit_completion(&stream->cmd_completion);
+
+ /*
+ * A UASP command consists of the command, data, and status
+ * stages, each operating sequentially from different endpoints.
+ *
+ * Each USB endpoint operates independently, and depending on
+ * hardware implementation, a completion callback for a transfer
+ * from one endpoint may not reflect the order of completion on
+ * the wire. This is particularly true for devices with
+ * endpoints that have independent interrupts and event buffers.
+ *
+ * The driver must still detect misbehaving hosts and respond
+ * with an overlap status. To reduce false overlap failures,
+ * allow the active and matching stream ID a brief 1ms to
+ * complete before responding with an overlap command failure.
+ * Overlap failure should be rare.
+ */
+ wait_for_completion_timeout(&stream->cmd_completion, msecs_to_jiffies(1));
+
+ /* If the previous stream is completed, retry the command. */
+ if (!hash_hashed(&stream->node)) {
+ usbg_submit_command(cmd->fu, cmd->req);
+ return;
+ }
+
+ /*
+ * The command isn't submitted to the target core, so we're safe
+ * to remove the bitmap index from the session tag pool.
+ */
+ sbitmap_queue_clear(&se_sess->sess_tag_pool,
+ cmd->se_cmd.map_tag,
+ cmd->se_cmd.map_cpu);
+
+ /*
+ * Overlap command tag detected. Cancel any pending transfer of
+ * the command submitted to target core.
+ */
+ active_cmd->tmr_rsp = RC_OVERLAPPED_TAG;
+ usbg_aborted_task(&active_cmd->se_cmd);
+
+ /* Send the response after the transfer is aborted. */
+ return;
+ }
+
uasp_send_tm_response(cmd);
}
@@ -1247,6 +1345,8 @@ static int usbg_submit_command(struct f_uas *fu, struct usb_request *req)
struct usbg_cmd *cmd;
struct usbg_tpg *tpg = fu->tpg;
struct tcm_usbg_nexus *tv_nexus;
+ struct uas_stream *stream;
+ struct hlist_node *tmp;
struct command_iu *cmd_iu;
u32 cmd_len;
u16 scsi_tag;
@@ -1282,6 +1382,23 @@ static int usbg_submit_command(struct f_uas *fu, struct usb_request *req)
goto skip;
}
+ hash_for_each_possible_safe(fu->stream_hash, stream, tmp, node, scsi_tag) {
+ struct usbg_cmd *active_cmd;
+ struct se_session *se_sess;
+ int i = stream - &fu->stream[0];
+
+ se_sess = cmd->fu->tpg->tpg_nexus->tvn_se_sess;
+ active_cmd = &((struct usbg_cmd *)se_sess->sess_cmd_map)[i];
+
+ if (active_cmd->tag == scsi_tag) {
+ cmd->tmr_rsp = RC_OVERLAPPED_TAG;
+ goto skip;
+ }
+ }
+
+ stream = &fu->stream[cmd->se_cmd.map_tag];
+ hash_add(fu->stream_hash, &stream->node, scsi_tag);
+
if (iu->iu_id == IU_ID_TASK_MGMT) {
struct task_mgmt_iu *tm_iu;
@@ -1293,6 +1410,7 @@ static int usbg_submit_command(struct f_uas *fu, struct usb_request *req)
cmd_len = (cmd_iu->len & ~0x3) + 16;
if (cmd_len > USBG_MAX_CMD) {
target_free_tag(tv_nexus->tvn_se_sess, &cmd->se_cmd);
+ hash_del(&stream->node);
return -EINVAL;
}
memcpy(cmd->cmd_buf, cmd_iu->cdb, cmd_len);
@@ -1443,6 +1561,7 @@ static void usbg_release_cmd(struct se_cmd *se_cmd)
se_cmd);
struct se_session *se_sess = se_cmd->se_sess;
+ cmd->tag = 0;
kfree(cmd->data_buf);
target_free_tag(se_sess, se_cmd);
}
@@ -2467,6 +2586,8 @@ static struct usb_function *tcm_alloc(struct usb_function_instance *fi)
fu->function.disable = tcm_disable;
fu->function.free_func = tcm_free;
fu->tpg = tpg_instances[i].tpg;
+
+ hash_init(fu->stream_hash);
mutex_unlock(&tpg_instances_lock);
return &fu->function;
diff --git a/drivers/usb/gadget/function/tcm.h b/drivers/usb/gadget/function/tcm.h
index d37358f09819..f6d6c86d10b3 100644
--- a/drivers/usb/gadget/function/tcm.h
+++ b/drivers/usb/gadget/function/tcm.h
@@ -4,6 +4,7 @@
#include <linux/kref.h>
/* #include <linux/usb/uas.h> */
+#include <linux/hashtable.h>
#include <linux/usb/composite.h>
#include <linux/usb/uas.h>
#include <linux/usb/storage.h>
@@ -103,6 +104,9 @@ struct uas_stream {
struct usb_request *req_in;
struct usb_request *req_out;
struct usb_request *req_status;
+
+ struct completion cmd_completion;
+ struct hlist_node node;
};
struct usbg_cdb {
@@ -135,6 +139,7 @@ struct f_uas {
struct usb_ep *ep_status;
struct usb_ep *ep_cmd;
struct uas_stream stream[USBG_NUM_CMDS];
+ DECLARE_HASHTABLE(stream_hash, UASP_SS_EP_COMP_LOG_STREAMS);
/* BOT */
struct bot_status bot_status;
--
2.28.0
