The cache may be flushed to the nonvolatile storage by writing to
FLUSH_CACHE byte (EXT_CSD byte [32]). When in command queueing mode, the
cache may be flushed by issuing a CMDQ_TASK_ DEV_MGMT (CMD48) with a
FLUSH_CACHE op-code. Either way, verify that The cache function is
turned ON before doing so.
fixes: 1e8e55b67030 (mmc: block: Add CQE support)
Reported-by: Brendan Peter <bpeter@xxxxxxxx>
Tested-by: Brendan Peter <bpeter@xxxxxxxx>
Signed-off-by: Avri Altman <avri.altman@xxxxxxx>
---
drivers/mmc/core/block.c | 7 +++++++
drivers/mmc/core/mmc.c | 2 +-
drivers/mmc/core/mmc_ops.h | 5 +++++
3 files changed, 13 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index 8bfd4d95b386..5b6501fc9fb7 100644
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -1476,6 +1476,11 @@ static int mmc_blk_cqe_issue_flush(struct mmc_queue *mq, struct request *req)
struct mmc_queue_req *mqrq = req_to_mmc_queue_req(req);
struct mmc_request *mrq = mmc_blk_cqe_prep_dcmd(mqrq, req);
+ if (mmc_card_mmc(mq->card) && !mmc_flush_allowed(mq->card)) {
+ blk_mq_end_request(req, BLK_STS_OK);
+ return -EPERM;
+ }
+
mrq->cmd->opcode = MMC_SWITCH;
mrq->cmd->arg = (MMC_SWITCH_MODE_WRITE_BYTE << 24) |
(EXT_CSD_FLUSH_CACHE << 16) |
@@ -2226,6 +2231,8 @@ enum mmc_issued mmc_blk_mq_issue_rq(struct mmc_queue *mq, struct request *req)
switch (req_op(req)) {
case REQ_OP_FLUSH:
ret = mmc_blk_cqe_issue_flush(mq, req);
+ if (ret == -EPERM)
+ return MMC_REQ_FINISHED;
break;
case REQ_OP_READ:
case REQ_OP_WRITE:
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 9ad4aa537867..e3da62ffcb5e 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -2037,7 +2037,7 @@ static int _mmc_flush_cache(struct mmc_card *card)
{
int err = 0;
- if (card->ext_csd.cache_size > 0 && card->ext_csd.cache_ctrl & 1) {
+ if (mmc_flush_allowed(card)) {
err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
EXT_CSD_FLUSH_CACHE, 1,
CACHE_FLUSH_TIMEOUT_MS);
diff --git a/drivers/mmc/core/mmc_ops.h b/drivers/mmc/core/mmc_ops.h
index 5782fdf4e8e9..2682bf66708a 100644
--- a/drivers/mmc/core/mmc_ops.h
+++ b/drivers/mmc/core/mmc_ops.h
@@ -19,6 +19,11 @@ enum mmc_busy_cmd {
struct mmc_host;
struct mmc_card;
+static inline bool mmc_flush_allowed(struct mmc_card *card)
+{
+ return card->ext_csd.cache_size > 0 && card->ext_csd.cache_ctrl & 1;
+}
+
int mmc_select_card(struct mmc_card *card);
int mmc_deselect_cards(struct mmc_host *host);
int mmc_set_dsr(struct mmc_host *host);
--
2.25.1
