@@ -625,13 +625,13 @@ static void dw_mci_start_request(struct dw_mci *host,
host->stop_cmdr = dw_mci_prepare_command(slot->mmc, mrq->stop);
}
+/* must be called with host->lock held */
static void dw_mci_queue_request(struct dw_mci *host, struct dw_mci_slot *slot,
struct mmc_request *mrq)
{
dev_vdbg(&slot->mmc->class_dev, "queue request: state=%d\n",
host->state);
- spin_lock_bh(&host->lock);
slot->mrq = mrq;
if (host->state == STATE_IDLE) {
@@ -640,8 +640,6 @@ static void dw_mci_queue_request(struct dw_mci *host, struct dw_mci_slot *slot,
} else {
list_add_tail(&slot->queue_node, &host->queue);
}
-
- spin_unlock_bh(&host->lock);
}
static void dw_mci_request(struct mmc_host *mmc, struct mmc_request *mrq)
@@ -651,14 +649,23 @@ static void dw_mci_request(struct mmc_host *mmc, struct mmc_request *mrq)
WARN_ON(slot->mrq);
+ /*
+ * The check for card presence and queueing of the request must be
+ * atomic, otherwise the card could be removed in between and the
+ * request wouldn't fail until another card was inserted.
+ */
+ spin_lock_bh(&host->lock);
+
if (!test_bit(DW_MMC_CARD_PRESENT, &slot->flags)) {
+ spin_unlock_bh(&host->lock);
mrq->cmd->error = -ENOMEDIUM;
mmc_request_done(mmc, mrq);
return;
}
- /* We don't support multiple blocks of weird lengths. */
dw_mci_queue_request(host, slot, mrq);
+
+ spin_unlock_bh(&host->lock);
}
static void dw_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
When a request is made, the card presence is checked and the request is queued. These two parts must be atomic with respect to card removal, or a card removal could be handled in between, and the new request wouldn't get cancelled until another card was inserted. Therefore move the spinlock protection from dw_mci_queue_request() up into dw_mci_request() to cover the presence check. Note that the test_bit() used for the presence check isn't atomic itself, so should have been protected by a spinlock anyway. Signed-off-by: James Hogan <james.hogan@imgtec.com> --- drivers/mmc/host/dw_mmc.c | 15 +++++++++++---- 1 files changed, 11 insertions(+), 4 deletions(-)