Skip to content

Commit

Permalink
usb: gadget: f_tcm: Handle TASK_MANAGEMENT commands
Browse files Browse the repository at this point in the history 
Handle target_core_fabric_ops TASK MANAGEMENT functions and their
response. If a TASK MANAGEMENT command is received, the driver will
interpret the function TMF_*, translate to TMR_*, and fire off a command
work executing target_submit_tmr(). On completion, it will handle the
TASK MANAGEMENT response through uasp_send_tm_response().

Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/50339586e36509dadb9c208b3314530993e673b6.1733876548.git.Thinh.Nguyen@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  • Loading branch information
Thinh Nguyen authored and Greg Kroah-Hartman committed Dec 24, 2024
1 parent 1d5d4e1 commit 20e9ab6
Show file tree
Hide file tree
Showing 2 changed files with 206 additions and 19 deletions.
220 changes: 201 additions & 19 deletions drivers/usb/gadget/function/f_tcm.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -12,6 +12,7 @@
#include <linux/string.h>
#include <linux/configfs.h>
#include <linux/ctype.h>
#include <linux/delay.h>
#include <linux/usb/ch9.h>
#include <linux/usb/composite.h>
#include <linux/usb/gadget.h>
Expand Down Expand Up @@ -449,6 +450,45 @@ static int usbg_bot_setup(struct usb_function *f,

/* Start uas.c code */

static int tcm_to_uasp_response(enum tcm_tmrsp_table code)
{
switch (code) {
case TMR_FUNCTION_FAILED:
return RC_TMF_FAILED;
case TMR_FUNCTION_COMPLETE:
case TMR_TASK_DOES_NOT_EXIST:
return RC_TMF_COMPLETE;
case TMR_LUN_DOES_NOT_EXIST:
return RC_INCORRECT_LUN;
case TMR_FUNCTION_REJECTED:
case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
default:
return RC_TMF_NOT_SUPPORTED;
}
}

static unsigned char uasp_to_tcm_func(int code)
{
switch (code) {
case TMF_ABORT_TASK:
return TMR_ABORT_TASK;
case TMF_ABORT_TASK_SET:
return TMR_ABORT_TASK_SET;
case TMF_CLEAR_TASK_SET:
return TMR_CLEAR_TASK_SET;
case TMF_LOGICAL_UNIT_RESET:
return TMR_LUN_RESET;
case TMF_CLEAR_ACA:
return TMR_CLEAR_ACA;
case TMF_I_T_NEXUS_RESET:
case TMF_QUERY_TASK:
case TMF_QUERY_TASK_SET:
case TMF_QUERY_ASYNC_EVENT:
default:
return TMR_UNKNOWN;
}
}

static void uasp_cleanup_one_stream(struct f_uas *fu, struct uas_stream *stream)
{
/* We have either all three allocated or none */
Expand Down Expand Up @@ -552,6 +592,61 @@ static void uasp_prepare_status(struct usbg_cmd *cmd)
stream->req_status->complete = uasp_status_data_cmpl;
}

static void uasp_prepare_response(struct usbg_cmd *cmd)
{
struct se_cmd *se_cmd = &cmd->se_cmd;
struct response_iu *rsp_iu = &cmd->response_iu;
struct uas_stream *stream = &cmd->fu->stream[se_cmd->map_tag];

cmd->state = UASP_QUEUE_COMMAND;
rsp_iu->iu_id = IU_ID_RESPONSE;
rsp_iu->tag = cpu_to_be16(cmd->tag);

if (cmd->tmr_rsp != RC_RESPONSE_UNKNOWN)
rsp_iu->response_code = cmd->tmr_rsp;
else
rsp_iu->response_code =
tcm_to_uasp_response(se_cmd->se_tmr_req->response);

/*
* The UASP driver must support all the task management functions listed
* in Table 20 of UAS-r04. To remain compliant while indicate that the
* TMR did not go through, report RC_TMF_FAILED instead of
* RC_TMF_NOT_SUPPORTED and print a warning to the user.
*/
switch (cmd->tmr_func) {
case TMF_ABORT_TASK:
case TMF_ABORT_TASK_SET:
case TMF_CLEAR_TASK_SET:
case TMF_LOGICAL_UNIT_RESET:
case TMF_CLEAR_ACA:
case TMF_I_T_NEXUS_RESET:
case TMF_QUERY_TASK:
case TMF_QUERY_TASK_SET:
case TMF_QUERY_ASYNC_EVENT:
if (rsp_iu->response_code == RC_TMF_NOT_SUPPORTED) {
struct usb_gadget *gadget = fuas_to_gadget(cmd->fu);

dev_warn(&gadget->dev, "TMF function %d not supported\n",
cmd->tmr_func);
rsp_iu->response_code = RC_TMF_FAILED;
}
break;
default:
break;
}

stream->req_status->is_last = 1;
stream->req_status->stream_id = cmd->tag;
stream->req_status->context = cmd;
stream->req_status->length = sizeof(struct response_iu);
stream->req_status->buf = rsp_iu;
stream->req_status->complete = uasp_status_data_cmpl;
}

static void usbg_release_cmd(struct se_cmd *se_cmd);
static int uasp_send_tm_response(struct usbg_cmd *cmd);

static void uasp_status_data_cmpl(struct usb_ep *ep, struct usb_request *req)
{
struct usbg_cmd *cmd = req->context;
Expand Down Expand Up @@ -590,9 +685,23 @@ static void uasp_status_data_cmpl(struct usb_ep *ep, struct usb_request *req)
break;

case UASP_QUEUE_COMMAND:
transport_generic_free_cmd(&cmd->se_cmd, 0);
usb_ep_queue(fu->ep_cmd, cmd->req, GFP_ATOMIC);
/*
* 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) {
struct se_session *se_sess;

se_sess = fu->tpg->tpg_nexus->tvn_se_sess;
sbitmap_queue_clear(&se_sess->sess_tag_pool,
cmd->se_cmd.map_tag,
cmd->se_cmd.map_cpu);
} else {
transport_generic_free_cmd(&cmd->se_cmd, 0);
}

usb_ep_queue(fu->ep_cmd, cmd->req, GFP_ATOMIC);
break;

default:
Expand All @@ -616,6 +725,18 @@ static int uasp_send_status_response(struct usbg_cmd *cmd)
return usb_ep_queue(fu->ep_status, stream->req_status, GFP_ATOMIC);
}

static int uasp_send_tm_response(struct usbg_cmd *cmd)
{
struct f_uas *fu = cmd->fu;
struct uas_stream *stream = &fu->stream[cmd->se_cmd.map_tag];
struct response_iu *iu = &cmd->response_iu;

iu->tag = cpu_to_be16(cmd->tag);
cmd->fu = fu;
uasp_prepare_response(cmd);
return usb_ep_queue(fu->ep_status, stream->req_status, GFP_ATOMIC);
}

static int uasp_send_read_response(struct usbg_cmd *cmd)
{
struct f_uas *fu = cmd->fu;
Expand Down Expand Up @@ -1016,9 +1137,23 @@ static int usbg_send_read_response(struct se_cmd *se_cmd)
return uasp_send_read_response(cmd);
}

static void usbg_cmd_work(struct work_struct *work)
static void usbg_submit_tmr(struct usbg_cmd *cmd)
{
struct se_session *se_sess;
struct se_cmd *se_cmd;
int flags = TARGET_SCF_ACK_KREF;

se_cmd = &cmd->se_cmd;
se_sess = cmd->fu->tpg->tpg_nexus->tvn_se_sess;

target_submit_tmr(se_cmd, se_sess,
cmd->response_iu.add_response_info,
cmd->unpacked_lun, NULL, uasp_to_tcm_func(cmd->tmr_func),
GFP_ATOMIC, cmd->tag, flags);
}

static void usbg_submit_cmd(struct usbg_cmd *cmd)
{
struct usbg_cmd *cmd = container_of(work, struct usbg_cmd, work);
struct se_cmd *se_cmd;
struct tcm_usbg_nexus *tv_nexus;
struct usbg_tpg *tpg;
Expand Down Expand Up @@ -1059,6 +1194,29 @@ static void usbg_cmd_work(struct work_struct *work)
TCM_UNSUPPORTED_SCSI_OPCODE, 0);
}

static void usbg_cmd_work(struct work_struct *work)
{
struct usbg_cmd *cmd = container_of(work, struct usbg_cmd, work);

/*
* Failure is detected by f_tcm here. Skip submitting the command to the
* target core if we already know the failing response and send the usb
* response to the host directly.
*/
if (cmd->tmr_rsp != RC_RESPONSE_UNKNOWN)
goto skip;

if (cmd->tmr_func)
usbg_submit_tmr(cmd);
else
usbg_submit_cmd(cmd);

return;

skip:
uasp_send_tm_response(cmd);
}

static struct usbg_cmd *usbg_get_cmd(struct f_uas *fu,
struct tcm_usbg_nexus *tv_nexus, u32 scsi_tag)
{
Expand All @@ -1085,34 +1243,58 @@ static void usbg_release_cmd(struct se_cmd *);

static int usbg_submit_command(struct f_uas *fu, struct usb_request *req)
{
struct command_iu *cmd_iu = req->buf;
struct iu *iu = req->buf;
struct usbg_cmd *cmd;
struct usbg_tpg *tpg = fu->tpg;
struct tcm_usbg_nexus *tv_nexus;
struct command_iu *cmd_iu;
u32 cmd_len;
u16 scsi_tag;

if (cmd_iu->iu_id != IU_ID_COMMAND) {
pr_err("Unsupported type %d\n", cmd_iu->iu_id);
return -EINVAL;
}

tv_nexus = tpg->tpg_nexus;
if (!tv_nexus) {
pr_err("Missing nexus, ignoring command\n");
return -EINVAL;
}

cmd_len = (cmd_iu->len & ~0x3) + 16;
if (cmd_len > USBG_MAX_CMD)
return -EINVAL;

scsi_tag = be16_to_cpup(&cmd_iu->tag);
scsi_tag = be16_to_cpup(&iu->tag);
cmd = usbg_get_cmd(fu, tv_nexus, scsi_tag);
if (IS_ERR(cmd)) {
pr_err("usbg_get_cmd failed\n");
return -ENOMEM;
}

cmd->req = req;
cmd->fu = fu;
cmd->tag = scsi_tag;
cmd->se_cmd.tag = scsi_tag;
cmd->tmr_func = 0;
cmd->tmr_rsp = RC_RESPONSE_UNKNOWN;
cmd->flags = 0;

cmd_iu = (struct command_iu *)iu;

/* Command and Task Management IUs share the same LUN offset */
cmd->unpacked_lun = scsilun_to_int(&cmd_iu->lun);

if (iu->iu_id != IU_ID_COMMAND && iu->iu_id != IU_ID_TASK_MGMT) {
cmd->tmr_rsp = RC_INVALID_INFO_UNIT;
goto skip;
}

if (iu->iu_id == IU_ID_TASK_MGMT) {
struct task_mgmt_iu *tm_iu;

tm_iu = (struct task_mgmt_iu *)iu;
cmd->tmr_func = tm_iu->function;
goto skip;
}

cmd_len = (cmd_iu->len & ~0x3) + 16;
if (cmd_len > USBG_MAX_CMD) {
target_free_tag(tv_nexus->tvn_se_sess, &cmd->se_cmd);
return -EINVAL;
}
memcpy(cmd->cmd_buf, cmd_iu->cdb, cmd_len);

switch (cmd_iu->prio_attr & 0x7) {
Expand All @@ -1134,10 +1316,7 @@ static int usbg_submit_command(struct f_uas *fu, struct usb_request *req)
break;
}

cmd->unpacked_lun = scsilun_to_int(&cmd_iu->lun);
cmd->req = req;
cmd->flags = 0;

skip:
INIT_WORK(&cmd->work, usbg_cmd_work);
queue_work(tpg->workqueue, &cmd->work);

Expand Down Expand Up @@ -1270,6 +1449,9 @@ static void usbg_release_cmd(struct se_cmd *se_cmd)

static void usbg_queue_tm_rsp(struct se_cmd *se_cmd)
{
struct usbg_cmd *cmd = container_of(se_cmd, struct usbg_cmd, se_cmd);

uasp_send_tm_response(cmd);
}

static void usbg_aborted_task(struct se_cmd *se_cmd)
Expand Down
5 changes: 5 additions & 0 deletions drivers/usb/gadget/function/tcm.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -85,8 +85,13 @@ struct usbg_cmd {
u16 tag;
u16 prio_attr;
struct sense_iu sense_iu;
struct response_iu response_iu;
enum uas_state state;

int tmr_func;
int tmr_rsp;
#define RC_RESPONSE_UNKNOWN 0xff

/* BOT only */
__le32 bot_tag;
unsigned int csw_code;
Expand Down

0 comments on commit 20e9ab6

Please sign in to comment.