This wraps single ioctl() commands into block requests using
the custom block layer request types REQ_OP_DRV_IN and
REQ_OP_DRV_OUT.
By doing this we are loosening the grip on the big host lock,
since two calls to mmc_get_card()/mmc_put_card() are removed.
We are storing the ioctl() in/out argument as a pointer in
the per-request struct mmc_blk_request container. Since we
now let the block layer allocate this data, blk_get_request()
will allocate it for us and we can immediately dereference
it and use it to pass the argument into the block layer.
Tested on the ux500 with the userspace:
mmc extcsd read /dev/mmcblk3
resulting in a successful EXTCSD info dump back to the
console.
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
---
drivers/mmc/core/block.c | 56 ++++++++++++++++++++++++++++++++++++++----------
drivers/mmc/core/queue.h | 3 +++
2 files changed, 48 insertions(+), 11 deletions(-)
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index 323f3790b629..640db4f57a31 100644
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -564,8 +564,10 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev,
{
struct mmc_blk_ioc_data *idata;
struct mmc_blk_data *md;
+ struct mmc_queue *mq;
struct mmc_card *card;
int err = 0, ioc_err = 0;
+ struct request *req;
/*
* The caller must have CAP_SYS_RAWIO, and must be calling this on the
@@ -591,17 +593,18 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev,
goto cmd_done;
}
- mmc_get_card(card);
-
- ioc_err = __mmc_blk_ioctl_cmd(card, md, idata);
-
- /* Always switch back to main area after RPMB access */
- if (md->area_type & MMC_BLK_DATA_AREA_RPMB)
- mmc_blk_part_switch(card, dev_get_drvdata(&card->dev));
-
- mmc_put_card(card);
-
+ /*
+ * Dispatch the ioctl() into the block request queue.
+ */
+ mq = &md->queue;
+ req = blk_get_request(mq->queue,
+ idata->ic.write_flag ? REQ_OP_DRV_OUT : REQ_OP_DRV_IN,
+ __GFP_RECLAIM);
+ req_to_mq_rq(req)->idata = idata;
+ blk_execute_rq(mq->queue, NULL, req, 0);
+ ioc_err = req_to_mq_rq(req)->ioc_result;
err = mmc_blk_ioctl_copy_to_user(ic_ptr, idata);
+ blk_put_request(req);
cmd_done:
mmc_blk_put(md);
@@ -611,6 +614,31 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev,
return ioc_err ? ioc_err : err;
}
+/*
+ * The ioctl commands come back from the block layer after it queued it and
+ * processed it with all other requests and then they get issued in this
+ * function.
+ */
+static void mmc_blk_ioctl_cmd_issue(struct mmc_queue *mq, struct request *req)
+{
+ struct mmc_queue_req *mq_rq;
+ struct mmc_blk_ioc_data *idata;
+ struct mmc_card *card = mq->card;
+ struct mmc_blk_data *md = mq->blkdata;
+ int ioc_err;
+
+ mq_rq = req_to_mq_rq(req);
+ idata = mq_rq->idata;
+ ioc_err = __mmc_blk_ioctl_cmd(card, md, idata);
+ mq_rq->ioc_result = ioc_err;
+
+ /* Always switch back to main area after RPMB access */
+ if (md->area_type & MMC_BLK_DATA_AREA_RPMB)
+ mmc_blk_part_switch(card, dev_get_drvdata(&card->dev));
+
+ blk_end_request_all(req, ioc_err);
+}
+
static int mmc_blk_ioctl_multi_cmd(struct block_device *bdev,
struct mmc_ioc_multi_cmd __user *user)
{
@@ -1854,7 +1882,13 @@ void mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
goto out;
}
- if (req && req_op(req) == REQ_OP_DISCARD) {
+ if (req &&
+ (req_op(req) == REQ_OP_DRV_IN || req_op(req) == REQ_OP_DRV_OUT)) {
+ /* complete ongoing async transfer before issuing ioctl()s */
+ if (mq->qcnt)
+ mmc_blk_issue_rw_rq(mq, NULL);
+ mmc_blk_ioctl_cmd_issue(mq, req);
+ } else if (req && req_op(req) == REQ_OP_DISCARD) {
/* complete ongoing async transfer before issuing discard */
if (mq->qcnt)
mmc_blk_issue_rw_rq(mq, NULL);
diff --git a/drivers/mmc/core/queue.h b/drivers/mmc/core/queue.h
index 8aa10ffdf622..aeb3408dc85e 100644
--- a/drivers/mmc/core/queue.h
+++ b/drivers/mmc/core/queue.h
@@ -22,6 +22,7 @@ static inline bool mmc_req_is_special(struct request *req)
struct task_struct;
struct mmc_blk_data;
+struct mmc_blk_ioc_data;
struct mmc_blk_request {
struct mmc_request mrq;
@@ -40,6 +41,8 @@ struct mmc_queue_req {
struct scatterlist *bounce_sg;
unsigned int bounce_sg_len;
struct mmc_async_req areq;
+ int ioc_result;
+ struct mmc_blk_ioc_data *idata;
};
struct mmc_queue {
--
2.9.3
