Linus Walleij 304419d8a7 mmc: core: Allocate per-request data using the block layer core ... The mmc_queue_req is a per-request state container the MMC core uses to carry bounce buffers, pointers to asynchronous requests and so on. Currently allocated as a static array of objects, then as a request comes in, a mmc_queue_req is assigned to it, and used during the lifetime of the request. This is backwards compared to how other block layer drivers work: they usally let the block core provide a per-request struct that get allocated right beind the struct request, and which can be obtained using the blk_mq_rq_to_pdu() helper. (The _mq_ infix in this function name is misleading: it is used by both the old and the MQ block layer.) The per-request struct gets allocated to the size stored in the queue variable .cmd_size initialized using the .init_rq_fn() and cleaned up using .exit_rq_fn(). The block layer code makes the MMC core rely on this mechanism to allocate the per-request mmc_queue_req state container. Doing this make a lot of complicated queue handling go away. We only need to keep the .qnct that keeps count of how many request are currently being processed by the MMC layer. The MQ block layer will replace also this once we transition to it. Doing this refactoring is necessary to move the ioctl() operations into custom block layer requests tagged with REQ_OP_DRV_[IN|OUT] instead of the custom code using the BigMMCHostLock that we have today: those require that per-request data be obtainable easily from a request after creating a custom request with e.g.: struct request *rq = blk_get_request(q, REQ_OP_DRV_IN, __GFP_RECLAIM); struct mmc_queue_req *mq_rq = req_to_mq_rq(rq); And this is not possible with the current construction, as the request is not immediately assigned the per-request state container, but instead it gets assigned when the request finally enters the MMC queue, which is way too late for custom requests. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> [Ulf: Folded in the fix to drop a call to blk_cleanup_queue()] Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Heiner Kallweit <hkallweit1@gmail.com>		2017-06-20 10:30:17 +02:00
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core	mmc: core: Allocate per-request data using the block layer core	2017-06-20 10:30:17 +02:00
host	mmc: core: Delete bounce buffer Kconfig option	2017-06-20 10:30:17 +02:00
Kconfig	mmc: block: Move files to core	2016-12-12 16:30:05 +01:00
Makefile	mmc: block: Move files to core	2016-12-12 16:30:05 +01:00