static DEFINE_MUTEX(open_lock);
-enum mmc_blk_status {
- MMC_BLK_SUCCESS = 0,
- MMC_BLK_PARTIAL,
- MMC_BLK_CMD_ERR,
- MMC_BLK_RETRY,
- MMC_BLK_ABORT,
- MMC_BLK_DATA_ERR,
- MMC_BLK_ECC_ERR,
- MMC_BLK_NOMEDIUM,
-};
-
module_param(perdev_minors, int, 0444);
MODULE_PARM_DESC(perdev_minors, "Minors numbers to allocate per device");
} else
areq = NULL;
areq = mmc_start_req(card->host, areq, (int *) &status);
- if (!areq)
+ if (!areq) {
+ if (status == MMC_BLK_NEW_REQUEST)
+ mq->flags |= MMC_QUEUE_NEW_REQUEST;
return 0;
+ }
mq_rq = container_of(areq, struct mmc_queue_req, mmc_active);
brq = &mq_rq->brq;
break;
case MMC_BLK_NOMEDIUM:
goto cmd_abort;
+ default:
+ pr_err("%s: Unhandled return value (%d)",
+ req->rq_disk->disk_name, status);
+ goto cmd_abort;
}
if (ret) {
int ret;
struct mmc_blk_data *md = mq->data;
struct mmc_card *card = md->queue.card;
+ struct mmc_host *host = card->host;
+ unsigned long flags;
if (req && !mq->mqrq_prev->req)
/* claim host only for the first request */
goto out;
}
+ mq->flags &= ~MMC_QUEUE_NEW_REQUEST;
if (req && req->cmd_flags & REQ_DISCARD) {
/* complete ongoing async transfer before issuing discard */
if (card->host->areq)
mmc_blk_issue_rw_rq(mq, NULL);
ret = mmc_blk_issue_flush(mq, req);
} else {
+ if (!req && host->areq) {
+ spin_lock_irqsave(&host->context_info.lock, flags);
+ host->context_info.is_waiting_last_req = true;
+ spin_unlock_irqrestore(&host->context_info.lock, flags);
+ }
ret = mmc_blk_issue_rw_rq(mq, req);
}
out:
- if (!req)
+ if (!req && !(mq->flags & MMC_QUEUE_NEW_REQUEST))
/* release host only when there are no more requests */
mmc_release_host(card->host);
return ret;
#define MMC_QUEUE_BOUNCESZ 65536
-#define MMC_QUEUE_SUSPENDED (1 << 0)
#define MMC_REQ_SPECIAL_MASK (REQ_DISCARD | REQ_FLUSH)
set_current_state(TASK_RUNNING);
cmd_flags = req ? req->cmd_flags : 0;
mq->issue_fn(mq, req);
+ if (mq->flags & MMC_QUEUE_NEW_REQUEST) {
+ mq->flags &= ~MMC_QUEUE_NEW_REQUEST;
+ continue; /* fetch again */
+ }
/*
* Current request becomes previous request
{
struct mmc_queue *mq = q->queuedata;
struct request *req;
+ unsigned long flags;
+ struct mmc_context_info *cntx;
if (!mq) {
while ((req = blk_fetch_request(q)) != NULL) {
return;
}
- if (!mq->mqrq_cur->req && !mq->mqrq_prev->req)
+ cntx = &mq->card->host->context_info;
+ if (!mq->mqrq_cur->req && mq->mqrq_prev->req) {
+ /*
+ * New MMC request arrived when MMC thread may be
+ * blocked on the previous request to be complete
+ * with no current request fetched
+ */
+ spin_lock_irqsave(&cntx->lock, flags);
+ if (cntx->is_waiting_last_req) {
+ cntx->is_new_req = true;
+ wake_up_interruptible(&cntx->wait);
+ }
+ spin_unlock_irqrestore(&cntx->lock, flags);
+ } else if (!mq->mqrq_cur->req && !mq->mqrq_prev->req)
wake_up_process(mq->thread);
}
}
EXPORT_SYMBOL(mmc_start_bkops);
+/*
+ * mmc_wait_data_done() - done callback for data request
+ * @mrq: done data request
+ *
+ * Wakes up mmc context, passed as a callback to host controller driver
+ */
+static void mmc_wait_data_done(struct mmc_request *mrq)
+{
+ mrq->host->context_info.is_done_rcv = true;
+ wake_up_interruptible(&mrq->host->context_info.wait);
+}
+
static void mmc_wait_done(struct mmc_request *mrq)
{
complete(&mrq->completion);
}
+/*
+ *__mmc_start_data_req() - starts data request
+ * @host: MMC host to start the request
+ * @mrq: data request to start
+ *
+ * Sets the done callback to be called when request is completed by the card.
+ * Starts data mmc request execution
+ */
+static int __mmc_start_data_req(struct mmc_host *host, struct mmc_request *mrq)
+{
+ mrq->done = mmc_wait_data_done;
+ mrq->host = host;
+ if (mmc_card_removed(host->card)) {
+ mrq->cmd->error = -ENOMEDIUM;
+ return -ENOMEDIUM;
+ }
+ mmc_start_request(host, mrq);
+
+ return 0;
+}
+
static int __mmc_start_req(struct mmc_host *host, struct mmc_request *mrq)
{
init_completion(&mrq->completion);
return 0;
}
+/*
+ * mmc_wait_for_data_req_done() - wait for request completed
+ * @host: MMC host to prepare the command.
+ * @mrq: MMC request to wait for
+ *
+ * Blocks MMC context till host controller will ack end of data request
+ * execution or new request notification arrives from the block layer.
+ * Handles command retries.
+ *
+ * Returns enum mmc_blk_status after checking errors.
+ */
+static int mmc_wait_for_data_req_done(struct mmc_host *host,
+ struct mmc_request *mrq,
+ struct mmc_async_req *next_req)
+{
+ struct mmc_command *cmd;
+ struct mmc_context_info *context_info = &host->context_info;
+ int err;
+ unsigned long flags;
+
+ while (1) {
+ wait_event_interruptible(context_info->wait,
+ (context_info->is_done_rcv ||
+ context_info->is_new_req));
+ spin_lock_irqsave(&context_info->lock, flags);
+ context_info->is_waiting_last_req = false;
+ spin_unlock_irqrestore(&context_info->lock, flags);
+ if (context_info->is_done_rcv) {
+ context_info->is_done_rcv = false;
+ context_info->is_new_req = false;
+ cmd = mrq->cmd;
+ if (!cmd->error || !cmd->retries ||
+ mmc_card_removed(host->card)) {
+ err = host->areq->err_check(host->card,
+ host->areq);
+ break; /* return err */
+ } else {
+ pr_info("%s: req failed (CMD%u): %d, retrying...\n",
+ mmc_hostname(host),
+ cmd->opcode, cmd->error);
+ cmd->retries--;
+ cmd->error = 0;
+ host->ops->request(host, mrq);
+ continue; /* wait for done/new event again */
+ }
+ } else if (context_info->is_new_req) {
+ context_info->is_new_req = false;
+ if (!next_req) {
+ err = MMC_BLK_NEW_REQUEST;
+ break; /* return err */
+ }
+ }
+ }
+ return err;
+}
+
static void mmc_wait_for_req_done(struct mmc_host *host,
struct mmc_request *mrq)
{
mmc_pre_req(host, areq->mrq, !host->areq);
if (host->areq) {
- mmc_wait_for_req_done(host, host->areq->mrq);
- err = host->areq->err_check(host->card, host->areq);
+ err = mmc_wait_for_data_req_done(host, host->areq->mrq,
+ areq);
+ if (err == MMC_BLK_NEW_REQUEST) {
+ if (error)
+ *error = err;
+ /*
+ * The previous request was not completed,
+ * nothing to return
+ */
+ return NULL;
+ }
/*
* Check BKOPS urgency for each R1 response
*/
}
if (!err && areq)
- start_err = __mmc_start_req(host, areq->mrq);
+ start_err = __mmc_start_data_req(host, areq->mrq);
if (host->areq)
mmc_post_req(host, host->areq->mrq, 0);
}
#endif
+/**
+ * mmc_init_context_info() - init synchronization context
+ * @host: mmc host
+ *
+ * Init struct context_info needed to implement asynchronous
+ * request mechanism, used by mmc core, host driver and mmc requests
+ * supplier.
+ */
+void mmc_init_context_info(struct mmc_host *host)
+{
+ spin_lock_init(&host->context_info.lock);
+ host->context_info.is_new_req = false;
+ host->context_info.is_done_rcv = false;
+ host->context_info.is_waiting_last_req = false;
+ init_waitqueue_head(&host->context_info.wait);
+}
+
static int __init mmc_init(void)
{
int ret;