summaryrefslogtreecommitdiff
path: root/drivers/mmc/core/queue.c
AgeCommit message (Collapse)Author
2020-07-13mmc: core: Correct misspelling of 'mq' in mmc_init_request()'s docsLee Jones
Correcting this misspelling squashes the following W=1 build warning(s): mmc/core/queue.c:212: warning: Function parameter or member 'mq' not described in '__mmc_init_request' mmc/core/queue.c:212: warning: Excess function parameter 'q' description in '__mmc_init_request' Signed-off-by: Lee Jones <lee.jones@linaro.org> Link: https://lore.kernel.org/r/20200701124702.908713-8-lee.jones@linaro.org Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2020-05-08mmc: block: Fix request completion in the CQE timeout pathAdrian Hunter
First, it should be noted that the CQE timeout (60 seconds) is substantial so a CQE request that times out is really stuck, and the race between timeout and completion is extremely unlikely. Nevertheless this patch fixes an issue with it. Commit ad73d6feadbd7b ("mmc: complete requests from ->timeout") preserved the existing functionality, to complete the request. However that had only been necessary because the block layer timeout handler had been marking the request to prevent it from being completed normally. That restriction was removed at the same time, the result being that a request that has gone will have been completed anyway. That is, the completion was unnecessary. At the time, the unnecessary completion was harmless because the block layer would ignore it, although that changed in kernel v5.0. Note for stable, this patch will not apply cleanly without patch "mmc: core: Fix recursive locking issue in CQE recovery path" Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Fixes: ad73d6feadbd7b ("mmc: complete requests from ->timeout") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200508062227.23144-1-adrian.hunter@intel.com Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2020-05-08mmc: core: Fix recursive locking issue in CQE recovery pathSarthak Garg
Consider the following stack trace -001|raw_spin_lock_irqsave -002|mmc_blk_cqe_complete_rq -003|__blk_mq_complete_request(inline) -003|blk_mq_complete_request(rq) -004|mmc_cqe_timed_out(inline) -004|mmc_mq_timed_out mmc_mq_timed_out acquires the queue_lock for the first time. The mmc_blk_cqe_complete_rq function also tries to acquire the same queue lock resulting in recursive locking where the task is spinning for the same lock which it has already acquired leading to watchdog bark. Fix this issue with the lock only for the required critical section. Cc: <stable@vger.kernel.org> Fixes: 1e8e55b67030 ("mmc: block: Add CQE support") Suggested-by: Sahitya Tummala <stummala@codeaurora.org> Signed-off-by: Sarthak Garg <sartgarg@codeaurora.org> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Link: https://lore.kernel.org/r/1588868135-31783-1-git-send-email-vbadigan@codeaurora.org Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2020-03-24mmc: Add MMC host software queue supportBaolin Wang
Now the MMC read/write stack will always wait for previous request is completed by mmc_blk_rw_wait(), before sending a new request to hardware, or queue a work to complete request, that will bring context switching overhead and spend some extra time to poll the card for busy completion for I/O writes via sending CMD13, especially for high I/O per second rates, to affect the IO performance. Thus this patch introduces MMC software queue interface based on the hardware command queue engine's interfaces, which is similar with the hardware command queue engine's idea, that can remove the context switching. Moreover we set the default queue depth as 64 for software queue, which allows more requests to be prepared, merged and inserted into IO scheduler to improve performance, but we only allow 2 requests in flight, that is enough to let the irq handler always trigger the next request without a context switch, as well as avoiding a long latency. Moreover the host controller should support HW busy detection for I/O operations when enabling the host software queue. That means, the host controller must not complete a data transfer request, until after the card stops signals busy. From the fio testing data in cover letter, we can see the software queue can improve some performance with 4K block size, increasing about 16% for random read, increasing about 90% for random write, though no obvious improvement for sequential read and write. Moreover we can expand the software queue interface to support MMC packed request or packed command in future. Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: Baolin Wang <baolin.wang7@gmail.com> Link: https://lore.kernel.org/r/4409c1586a9b3ed20d57ad2faf6c262fc3ccb6e2.1581478568.git.baolin.wang7@gmail.com Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-09-12mmc: queue: Fix bigger segments usageYoshihiro Shimoda
The commit 38c38cb73223 ("mmc: queue: use bigger segments if DMA MAP layer can merge the segments") always enables the bugger segments if DMA MAP layer can merge the segments, but some controllers (SDHCI) have strictly limitation about the segments size, and then the commit breaks on the controllers. To fix the issue, this patch adds a new flag MMC_CAP2_MERGE_CAPABLE into the struct mmc_host and the bigger segments usage is disabled as default. Reported-by: Thierry Reding <treding@nvidia.com> Fixes: 38c38cb73223 ("mmc: queue: use bigger segments if DMA MAP layer can merge the segments") Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-03mmc: queue: use bigger segments if DMA MAP layer can merge the segmentsYoshihiro Shimoda
When the max_segs of a mmc host is smaller than 512, the mmc subsystem tries to use 512 segments if DMA MAP layer can merge the segments, and then the mmc subsystem exposes such information to the block layer by using blk_queue_can_use_dma_map_merging(). Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-07-22mmc: mmc_spi: Enable stable writesAndreas Koop
While using the mmc_spi driver occasionally errors like this popped up: mmcblk0: error -84 transferring data end_request: I/O error, dev mmcblk0, sector 581756 I looked on the Internet for occurrences of the same problem and came across a helpful post [1]. It includes source code to reproduce the bug. There is also an analysis about the cause. During transmission data in the supplied buffer is being modified. Thus the previously calculated checksum is not correct anymore. After some digging I found out that device drivers are supposed to report they need stable writes. To fix this I set the appropriate flag at queue initialization if CRC checksumming is enabled for that SPI host. [1] https://groups.google.com/forum/#!msg/sim1/gLlzWeXGFr8/KevXinUXfc8J Signed-off-by: Andreas Koop <andreas.koop@zf.com> [shihpo: Rebase on top of v5.3-rc1] Signed-off-by: ShihPo Hung <shihpo.hung@sifive.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> CC: stable@vger.kernel.org Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-07-11Merge tag 'mmc-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmcLinus Torvalds
Pull MMC updates from Ulf Hansson: "MMC core: - Let the dma map ops deal with bouncing and drop dma_max_pfn() from the dma-mapping interface for ARM - Convert the generic MMC DT doc to YAML schemas - Drop questionable support for powered-on re-init of SDIO cards at runtime resume and for SDIO HW reset - Prevent questionable re-init of powered-on removable SDIO cards at system resume - Cleanup and clarify some SDIO core code MMC host: - tmio: Make runtime PM enablement more flexible for variants - tmio/renesas_sdhi: Rename DT doc tmio_mmc.txt to renesas,sdhi.txt to clarify - sdhci-pci: Add support for Intel EHL - sdhci-pci-o2micro: Enable support for 8-bit bus - sdhci-msm: Prevent acquiring a mutex while holding a spin_lock - sdhci-of-esdhc: Improve clock management and tuning - sdhci_am654: Enable support for 4 and 8-bit bus on J721E - sdhci-sprd: Use pinctrl for a proper signal voltage switch - sdhci-sprd: Add support for HS400 enhanced strobe mode - sdhci-sprd: Enable PHY DLL and allow delay config to stabilize the clock - sdhci-sprd: Add support for optional gate clock - sunxi-mmc: Convert DT doc to YAML schemas - meson-gx: Add support for broken DRAM access for DMA MEMSTICK core: - Fixup error path of memstick_init()" * tag 'mmc-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc: (52 commits) mmc: sdhci_am654: Add dependency on MMC_SDHCI_AM654 mmc: alcor: remove a redundant greater or equal to zero comparison mmc: sdhci-msm: fix mutex while in spinlock mmc: sdhci_am654: Make some symbols static dma-mapping: remove dma_max_pfn mmc: core: let the dma map ops handle bouncing dt-binding: mmc: rename tmio_mmc.txt to renesas,sdhi.txt mmc: sdhci-sprd: Add pin control support for voltage switch dt-bindings: mmc: sprd: Add pinctrl support mmc: sdhci-sprd: Add start_signal_voltage_switch ops mmc: sdhci-pci: Add support for Intel EHL mmc: tmio: Use dma_max_mapping_size() instead of a workaround mmc: sdio: Drop unused in-parameter from mmc_sdio_init_card() mmc: sdio: Drop unused in-parameter to mmc_sdio_reinit_card() mmc: sdio: Don't re-initialize powered-on removable SDIO cards at resume mmc: sdio: Drop powered-on re-init at runtime resume and HW reset mmc: sdio: Move comment about re-initialization to mmc_sdio_reinit_card() mmc: sdio: Drop mmc_claim|release_host() in mmc_sdio_power_restore() mmc: sdio: Turn sdio_run_irqs() into static mmc: sdhci: Fix indenting on SDHCI_CTRL_8BITBUS ...
2019-07-10mmc: core: let the dma map ops handle bouncingChristoph Hellwig
Just like we do for all other block drivers. Especially as the limit imposed at the moment might be way to pessimistic for iommus. This also means we are not going to set a bounce limit for the queue, in case we have a dma mask. On most architectures it was never needed, the major hold out was x86-32 with PAE, but that has been fixed by now. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05mmc: also set max_segment_size in the deviceChristoph Hellwig
If we only set the max_segment_size on the queue an IOMMU merge might create bigger segments again, so limit the IOMMU merges as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-05-06mmc: core: Fix tag set memory leakRaul E Rangel
The tag set is allocated in mmc_init_queue but never freed. This results in a memory leak. This change makes sure we free the tag set when the queue is also freed. Signed-off-by: Raul E Rangel <rrangel@chromium.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Fixes: 81196976ed94 ("mmc: block: Add blk-mq support") Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-03-08Merge tag 'for-5.1/block-20190302' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block layer updates from Jens Axboe: "Not a huge amount of changes in this round, the biggest one is that we finally have Mings multi-page bvec support merged. Apart from that, this pull request contains: - Small series that avoids quiescing the queue for sysfs changes that match what we currently have (Aleksei) - Series of bcache fixes (via Coly) - Series of lightnvm fixes (via Mathias) - NVMe pull request from Christoph. Nothing major, just SPDX/license cleanups, RR mp policy (Hannes), and little fixes (Bart, Chaitanya). - BFQ series (Paolo) - Save blk-mq cpu -> hw queue mapping, removing a pointer indirection for the fast path (Jianchao) - fops->iopoll() added for async IO polling, this is a feature that the upcoming io_uring interface will use (Christoph, me) - Partition scan loop fixes (Dongli) - mtip32xx conversion from managed resource API (Christoph) - cdrom registration race fix (Guenter) - MD pull from Song, two minor fixes. - Various documentation fixes (Marcos) - Multi-page bvec feature. This brings a lot of nice improvements with it, like more efficient splitting, larger IOs can be supported without growing the bvec table size, and so on. (Ming) - Various little fixes to core and drivers" * tag 'for-5.1/block-20190302' of git://git.kernel.dk/linux-block: (117 commits) block: fix updating bio's front segment size block: Replace function name in string with __func__ nbd: propagate genlmsg_reply return code floppy: remove set but not used variable 'q' null_blk: fix checking for REQ_FUA block: fix NULL pointer dereference in register_disk fs: fix guard_bio_eod to check for real EOD errors blk-mq: use HCTX_TYPE_DEFAULT but not 0 to index blk_mq_tag_set->map block: optimize bvec iteration in bvec_iter_advance block: introduce mp_bvec_for_each_page() for iterating over page block: optimize blk_bio_segment_split for single-page bvec block: optimize __blk_segment_map_sg() for single-page bvec block: introduce bvec_nth_page() iomap: wire up the iopoll method block: add bio_set_polled() helper block: wire up block device iopoll method fs: add an iopoll method to struct file_operations loop: set GENHD_FL_NO_PART_SCAN after blkdev_reread_part() loop: do not print warn message if partition scan is successful block: bounce: make sure that bvec table is updated ...
2019-02-27mmc: core: align max segment size with logical block sizeMing Lei
Logical block size is the lowest possible block size that the storage device can address. Max segment size is often related with controller's DMA capability. And it is reasonable to align max segment size with logical block size. SDHCI sets un-aligned max segment size, and causes ADMA error, so fix it by aligning max segment size with logical block size. Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Naresh Kamboju <naresh.kamboju@linaro.org> Cc: Faiz Abbas <faiz_abbas@ti.com> Cc: linux-block@vger.kernel.org Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2019-02-15block: kill BLK_MQ_F_SG_MERGEMing Lei
QUEUE_FLAG_NO_SG_MERGE has been killed, so kill BLK_MQ_F_SG_MERGE too. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-17mmc: stop abusing the request queue_lock pointerChristoph Hellwig
Replace the lock in mmc_blk_data that is only used through a pointer in struct mmc_queue and to protect fields in that structure with an actual lock in struct mmc_queue. Suggested-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-15mmc: stop abusing the request queue_lock pointerChristoph Hellwig
mmc uses the block layer struct request pointer to indirect their own lock to the mmc_queue structure, given that the original lock isn't reachable outside of block.c. Add a lock pointer to struct mmc_queue instead and stop overriding the block layer lock which protects fields entirely separate from the mmc use. Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-15mmc: simplify queue initializationChristoph Hellwig
Merge three functions initializing the queue into a single one, and drop an unused argument for it. Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-08-21mmc: block: Fix unsupported parallel dispatch of requestsAdrian Hunter
The mmc block driver does not support parallel dispatch of requests. In normal circumstances, all requests are anyway funneled through a single work item, so parallel dispatch never happens. However it can happen if there is no elevator. Fix that by detecting if a dispatch is in progress and returning busy (BLK_STS_RESOURCE) in that case Fixes: 81196976ed94 ("mmc: block: Add blk-mq support") Cc: stable@vger.kernel.org # v4.16+ Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2018-05-29mmc: complete requests from ->timeoutChristoph Hellwig
By completing the request entirely in the driver we can remove the BLK_EH_HANDLED return value and thus the split responsibility between the driver and the block layer that has been causing trouble. [While this keeps existing behavior it seems to mismatch the comment, maintainers please chime in!] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-03-08block: Use blk_queue_flag_*() in drivers instead of queue_flag_*()Bart Van Assche
This patch has been generated as follows: for verb in set_unlocked clear_unlocked set clear; do replace-in-files queue_flag_${verb} blk_queue_flag_${verb%_unlocked} \ $(git grep -lw queue_flag_${verb} drivers block/bsg*) done Except for protecting all queue flag changes with the queue lock this patch does not change any functionality. Cc: Mike Snitzer <snitzer@redhat.com> Cc: Shaohua Li <shli@fb.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Hannes Reinecke <hare@suse.de> Cc: Ming Lei <ming.lei@redhat.com> Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-12-11mmc: block: Remove code no longer needed after the switch to blk-mqAdrian Hunter
Remove code no longer needed after the switch to blk-mq. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-12-11mmc: block: make function mmc_cqe_issue_type staticColin Ian King
The function mmc_cqe_issue_type is local to the source and does not need to be in global scope, so make it static. Cleans up sparse warning: drivers/mmc/core/queue.c:62:21: warning: symbol 'mmc_cqe_issue_type' was not declared. Should it be static? Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-12-11mmc: block: blk-mq: Add support for direct completionAdrian Hunter
For blk-mq, add support for completing requests directly in the ->done callback. That means that error handling and urgent background operations must be handled by recovery_work in that case. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Linus Walleij <linus.walleij@linaro.org>
2017-12-11mmc: block: Add CQE supportAdrian Hunter
Add CQE support to the block driver, including: - optionally using DCMD for flush requests - "manually" issuing discard requests - issuing read / write requests to the CQE - supporting block-layer timeouts - handling recovery - supporting re-tuning CQE offers 25% - 50% better random multi-threaded I/O. There is a slight (e.g. 2%) drop in sequential read speed but no observable change to sequential write. CQE automatically sends the commands to complete requests. However it only supports reads / writes and so-called "direct commands" (DCMD). Furthermore DCMD is limited to one command at a time, but discards require 3 commands. That makes issuing discards through CQE very awkward, but some CQE's don't support DCMD anyway. So for discards, the existing non-CQE approach is taken, where the mmc core code issues the 3 commands one at a time i.e. mmc_erase(). Where DCMD is used, is for issuing flushes. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Linus Walleij <linus.walleij@linaro.org>
2017-12-11mmc: block: Add blk-mq supportAdrian Hunter
Define and use a blk-mq queue. Discards and flushes are processed synchronously, but reads and writes asynchronously. In order to support slow DMA unmapping, DMA unmapping is not done until after the next request is started. That means the request is not completed until then. If there is no next request then the completion is done by queued work. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Linus Walleij <linus.walleij@linaro.org>
2017-12-11mmc: block: Simplify cleaning up the queueAdrian Hunter
Use blk_cleanup_queue() to shutdown the queue when the driver is removed, and instead get an extra reference to the queue to prevent the queue being freed before the final mmc_blk_put(). Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Linus Walleij <linus.walleij@linaro.org>
2017-12-11mmc: block: No need to export mmc_cleanup_queue()Adrian Hunter
mmc_cleanup_queue() is not used by a different module. Do not export it. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Linus Walleij <linus.walleij@linaro.org>
2017-10-30mmc: block: Factor out mmc_setup_queue()Adrian Hunter
Factor out some common code that will also be used with blk-mq. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-10-30mmc: block: Delete mmc_access_rpmb()Linus Walleij
This function is used by the block layer queue to bail out of requests if the current request is towards an RPMB "block device". This was done to avoid boot time scanning of this "block device" which was never really a block device, thus duct-taping over the fact that it was badly engineered. This problem is now gone as we removed the offending RPMB block device in another patch and replaced it with a character device. Cc: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-10-04mmc: Delete bounce buffer handlingLinus Walleij
In may, Steven sent a patch deleting the bounce buffer handling and the CONFIG_MMC_BLOCK_BOUNCE option. I chose the less invasive path of making it a runtime config option, and we merged that successfully for kernel v4.12. The code is however just standing in the way and taking up space for seemingly no gain on any systems in wide use today. Pierre says the code was there to improve speed on TI SDHCI controllers on certain HP laptops and possibly some Ricoh controllers as well. Early SDHCI controllers lacked the scatter-gather feature, which made software bounce buffers a significant speed boost. We are clearly talking about the list of SDHCI PCI-based MMC/SD card readers found in the pci_ids[] list in drivers/mmc/host/sdhci-pci-core.c. The TI SDHCI derivative is not supported by the upstream kernel. This leaves the Ricoh. What we can however notice is that the x86 defconfigs in the kernel did not enable CONFIG_MMC_BLOCK_BOUNCE option, which means that any such laptop would have to have a custom configured kernel to actually take advantage of this bounce buffer speed-up. It simply seems like there was a speed optimization for the Ricoh controllers that noone was using. (I have not checked the distro defconfigs but I am pretty sure the situation is the same there.) Bounce buffers increased performance on the OMAP HSMMC at one point, and was part of the original submission in commit a45c6cb81647 ("[ARM] 5369/1: omap mmc: Add new omap hsmmc controller for 2430 and 34xx, v3") This optimization was removed in commit 0ccd76d4c236 ("omap_hsmmc: Implement scatter-gather emulation") which found that scatter-gather emulation provided even better performance. The same was introduced for SDHCI in commit 2134a922c6e7 ("sdhci: scatter-gather (ADMA) support") I am pretty positively convinced that software scatter-gather emulation will do for any host controller what the bounce buffers were doing. Essentially, the bounce buffer was a reimplementation of software scatter-gather-emulation in the MMC subsystem, and it should be done away with. Cc: Pierre Ossman <pierre@ossman.eu> Cc: Juha Yrjola <juha.yrjola@solidboot.com> Cc: Steven J. Hill <Steven.Hill@cavium.com> Cc: Shawn Lin <shawn.lin@rock-chips.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Suggested-by: Steven J. Hill <Steven.Hill@cavium.com> Suggested-by: Shawn Lin <shawn.lin@rock-chips.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-09-08mmc: block: Fix incorrectly initialized requestsAdrian Hunter
mmc_init_request() depends on card->bouncesz so it must be calculated before blk_init_allocated_queue() starts allocating requests. Reported-by: Seraphime Kirkovski <kirkseraph@gmail.com> Fixes: 304419d8a7e9 ("mmc: core: Allocate per-request data using the..") Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Tested-by: Seraphime Kirkovski <kirkseraph@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Pavel Machek <pavel@ucw.cz>
2017-07-04Merge tag 'mmc-v4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmcLinus Torvalds
Pull MMC updates from Ulf Hansson: "MMC core: - Add support to enable irq wake for slot gpio - Remove MMC_CAP2_HC_ERASE_SZ and make it the default behaviour - Improve R1 response error checks for stop commands - Cleanup and clarify some MMC specific code - Keep card runtime resumed while adding SDIO function devices - Use device_property_read instead of of_property_read in mmc_of_parse() - Move boot partition locking into a driver op to enable proper I/O scheduling - Move multi/single-ioctl() to use block layer to enable proper I/O scheduling - Delete bounce buffer Kconfig option - Improve the eMMC HW reset support provided via the eMMC pwrseq - Add host API to manage SDIO IRQs from a workqueue MMC host: - dw_mmc: Drop support for multiple slots - dw_mmc: Use device_property_read instead of of_property_read - dw_mmc-rockchip: Optional improved tuning to greatly decrease tuning time - dw_mmc: Prevent rpm suspend for SDIO IRQs instead of always for SDIO cards - dw_mmc: Convert to use MMC_CAP2_SDIO_IRQ_NOTHREAD for SDIO IRQs - omap_hsmmc: Convert to mmc regulator APIs to consolidate code - omap_hsmmc: Deprecate "vmmc_aux" in DT and use "vqmmc" instead - tmio: make sure SDIO gets reinitialized after resume - sdhi: add CMD23 support to R-Car Gen2 & Gen3 - tmio: add CMD23 support - sdhi/tmio: Refactor code and rename files to simplify Kconfig options - sdhci-pci: Enable card detect wake for Intel BYT-related SD controllers - sdhci-pci: Add support for Intel CNP - sdhci-esdhc-imx: Remove ENGcm07207 workaround - allow multi block transfers - sdhci-esdhc-imx: Allow all supported prescaler values - sdhci-esdhc-imx: Fix DAT line software reset - sdhci-esdhc: Add SDHCI_QUIRK_32BIT_DMA_ADDR - atmel-mci: Drop AVR32 support" * tag 'mmc-v4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc: (86 commits) mmc: dw_mmc: remove the unnecessary slot variable mmc: dw_mmc: use the 'slot' instead of 'cur_slot' mmc: dw_mmc: remove the 'id' arguments about functions relevant to slot mmc: dw_mmc: change the array of slots mmc: dw_mmc: remove the loop about finding slots mmc: dw_mmc: deprecated the "num-slots" property mmc: dw_mmc-rockchip: parse rockchip, desired-num-phases from DT dt-bindings: rockchip-dw-mshc: add optional rockchip, desired-num-phases mmc: renesas-sdhi: improve checkpatch cleanness mmc: tmio: improve checkpatch cleanness mmc: sdhci-pci: Enable card detect wake for Intel BYT-related SD controllers mmc: slot-gpio: Add support to enable irq wake on cd_irq mmc: core: Remove MMC_CAP2_HC_ERASE_SZ mmc: core: for data errors, take response of stop cmd into account mmc: core: check also R1 response for stop commands mmc: core: Clarify code for sending CSD mmc: core: Drop mmc_all_send_cid() and use mmc_send_cxd_native() instead mmc: core: Re-factor code for sending CID mmc: core: Remove redundant code in mmc_send_cid() mmc: core: Make mmc_can_reset() static ...
2017-06-27mmc/block: remove a call to blk_queue_bounce_limitChristoph Hellwig
BLK_BOUNCE_ANY is the defauly now, so the call is superflous. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20mmc: block: remove req back pointerLinus Walleij
Just as we can use blk_mq_rq_from_pdu() to get the per-request tag we can use blk_mq_rq_to_pdu() to get a request from a tag. Introduce a static inline helper so we are on the clear what is happening. Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-06-20mmc: core: Allocate per-request data using the block layer coreLinus Walleij
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>
2017-06-20mmc: core: Delete bounce buffer Kconfig optionLinus Walleij
This option is activated by all multiplatform configs and what not so we almost always have it turned on, and the memory it saves is negligible, even more so moving forward. The actual bounce buffer only gets allocated only when used, the only thing the ifdefs are saving is a little bit of code. It is highly improper to have this as a Kconfig option that get turned on by Kconfig, make this a pure runtime-thing and let the host decide whether we use bounce buffers. We add a new property "disable_bounce" to the host struct. Notice that mmc_queue_calc_bouncesz() already disables the bounce buffers if host->max_segs != 1, so any arch that has a maximum number of segments higher than 1 will have bounce buffers disabled. The option CONFIG_MMC_BLOCK_BOUNCE is default y so the majority of platforms in the kernel already have it on, and it then gets turned off at runtime since most of these have a host->max_segs > 1. The few exceptions that have host->max_segs == 1 and still turn off the bounce buffering are those that disable it in their defconfig. Those are the following: arch/arm/configs/colibri_pxa300_defconfig arch/arm/configs/zeus_defconfig - Uses MMC_PXA, drivers/mmc/host/pxamci.c - Sets host->max_segs = NR_SG, which is 1 - This needs its bounce buffer deactivated so we set host->disable_bounce to true in the host driver arch/arm/configs/davinci_all_defconfig - Uses MMC_DAVINCI, drivers/mmc/host/davinci_mmc.c - This driver sets host->max_segs to MAX_NR_SG, which is 16 - That means this driver anyways disabled bounce buffers - No special action needed for this platform arch/arm/configs/lpc32xx_defconfig arch/arm/configs/nhk8815_defconfig arch/arm/configs/u300_defconfig - Uses MMC_ARMMMCI, drivers/mmc/host/mmci.[c|h] - This driver by default sets host->max_segs to NR_SG, which is 128, unless a DMA engine is used, and in that case the number of segments are also > 1 - That means this driver already disables bounce buffers - No special action needed for these platforms arch/arm/configs/sama5_defconfig - Uses MMC_SDHCI, MMC_SDHCI_PLTFM, MMC_SDHCI_OF_AT91, MMC_ATMELMCI - Uses drivers/mmc/host/sdhci.c - Normally sets host->max_segs to SDHCI_MAX_SEGS which is 128 and thus disables bounce buffers - Sets host->max_segs to 1 if SDHCI_USE_SDMA is set - SDHCI_USE_SDMA is only set by SDHCI on PCI adapers - That means that for this platform bounce buffers are already disabled at runtime - No special action needed for this platform arch/blackfin/configs/CM-BF533_defconfig arch/blackfin/configs/CM-BF537E_defconfig - Uses MMC_SPI (a simple MMC card connected on SPI pins) - Uses drivers/mmc/host/mmc_spi.c - Sets host->max_segs to MMC_SPI_BLOCKSATONCE which is 128 - That means this platform already disables bounce buffers at runtime - No special action needed for these platforms arch/mips/configs/cavium_octeon_defconfig - Uses MMC_CAVIUM_OCTEON, drivers/mmc/host/cavium.c - Sets host->max_segs to 16 or 1 - Setting host->disable_bounce to be sure for the 1 case arch/mips/configs/qi_lb60_defconfig - Uses MMC_JZ4740, drivers/mmc/host/jz4740_mmc.c - This sets host->max_segs to 128 so bounce buffers are already runtime disabled - No action needed for this platform It would be interesting to come up with a list of the platforms that actually end up using bounce buffers. I have not been able to infer such a list, but it occurs when host->max_segs == 1 and the bounce buffering is not explicitly disabled. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-06-09block: introduce new block status code typeChristoph Hellwig
Currently we use nornal Linux errno values in the block layer, and while we accept any error a few have overloaded magic meanings. This patch instead introduces a new blk_status_t value that holds block layer specific status codes and explicitly explains their meaning. Helpers to convert from and to the previous special meanings are provided for now, but I suspect we want to get rid of them in the long run - those drivers that have a errno input (e.g. networking) usually get errnos that don't know about the special block layer overloads, and similarly returning them to userspace will usually return somethings that strictly speaking isn't correct for file system operations, but that's left as an exercise for later. For now the set of errors is a very limited set that closely corresponds to the previous overloaded errno values, but there is some low hanging fruite to improve it. blk_status_t (ab)uses the sparse __bitwise annotations to allow for sparse typechecking, so that we can easily catch places passing the wrong values. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-02Merge tag 'mmc-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmcLinus Torvalds
Pull MMC updates from Ulf Hansson: "MMC core: - Continue to re-factor code to prepare for eMMC CMDQ and blkmq support - Introduce queue semantics to prepare for eMMC CMDQ and blkmq support - Add helper functions to manage temporary enable/disable of eMMC CMDQ - Improve wait-busy detection for SDIO MMC host: - cavium: Add driver to support Cavium controllers - cavium: Extend Cavium driver to support Octeon and ThunderX SOCs - bcm2835: Add new driver for Broadcom BCM2835 controller - sdhci-xenon: Add driver to support Marvell Xenon SDHCI controller - sdhci-tegra: Add support for the Tegra186 variant - sdhci-of-esdhc: Support for UHS-I SD cards - sdhci-of-esdhc: Support for eMMC HS200 cards - sdhci-cadence: Add eMMC HS400 enhanced strobe support - sdhci-esdhc-imx: Reset tuning circuit when needed - sdhci-pci: Modernize and clean-up some PM related code - sdhci-pci: Avoid re-tuning at runtime PM for some Intel devices - sdhci-pci|acpi: Use aggressive PM for some Intel BYT controllers - sdhci: Re-factoring and modernizations - sdhci: Optimize delay loops - sdhci: Improve register dump print format - sdhci: Add support for the Command Queue Engine - meson-gx: Various improvements and clean-ups - meson-gx: Add support for CMD23 - meson-gx: Basic tuning support to avoid CRC errors - s3cmci: Enable probing via DT - mediatek: Improve tuning support for eMMC HS200 and HS400 mode - tmio: Improve DMA support - tmio: Use correct response for CMD12 - dw_mmc: Minor improvements and clean-ups" * tag 'mmc-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc: (148 commits) mmc: sdhci-of-esdhc: limit SD clock for ls1012a/ls1046a mmc: sdhci-of-esdhc: poll ESDHC_CLOCK_STABLE bit with udelay mmc: sdhci-xenon: Fix default value of LOGIC_TIMING_ADJUST for eMMC5.0 PHY mmc: sdhci-xenon: Fix the work flow in xenon_remove(). MIPS: Octeon: cavium_octeon_defconfig: Enable Octeon MMC mmc: sdhci-xenon: Remove redundant dev_err call in get_dt_pad_ctrl_data() mmc: cavium: Use module_pci_driver to simplify the code mmc: cavium: Add MMC support for Octeon SOCs. mmc: cavium: Fix detection of block or byte addressing. mmc: core: Export API to allow hosts to get the card address mmc: sdio: Fix sdio wait busy implement limitation mmc: sdhci-esdhc-imx: reset tuning circuit when power on mmc card clk: apn806: fix spelling mistake: "mising" -> "missing" mmc: sdhci-of-esdhc: add delay between tuning cycles mmc: sdhci: Control the delay between tuning commands mmc: sdhci-of-esdhc: add tuning support mmc: sdhci-of-esdhc: add support for signal voltage switch mmc: sdhci-of-esdhc: add peripheral clock support mmc: sdhci-pci: Allow for 3 bytes from Intel DSM mmc: cavium: Fix a shift wrapping bug ...
2017-04-24mmc: queue: Share mmc request array between partitionsAdrian Hunter
eMMC can have multiple internal partitions that are represented as separate disks / queues. However switching between partitions is only done when the queue is empty. Consequently the array of mmc requests that are queued can be shared between partitions saving memory. Keep a pointer to the mmc request queue on the card, and use that instead of allocating a new one for each partition. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-04-24mmc: block: Introduce queue semanticsAdrian Hunter
Change from viewing the requests in progress as 'current' and 'previous', to viewing them as a queue. The current request is allocated to the first free slot. The presence of incomplete requests is determined from the count (mq->qcnt) of entries in the queue. Non-read-write requests (i.e. discards and flushes) are not added to the queue at all and require no special handling. Also no special handling is needed for the MMC_BLK_NEW_REQUEST case. As well as allowing an arbitrarily sized queue, the queue thread function is significantly simpler. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-04-08mmc: remove the discard_zeroes_data flagChristoph Hellwig
mmc only supports discarding on large alignments, so the zeroing code would always fall back to explicit writings of zeroes. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-02-21Merge tag 'mmc-v4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmcLinus Torvalds
Pull MMC updates from Ulf Hansson: "MMC core: - Add support for Marvell SD8787 Wifi/BT chip - Improve UHS support for SDIO - Invent MMC_CAP_3_3V_DDR and a DT binding for eMMC DDR 3.3V mode - Detect Auto BKOPS enable bit - Export eMMC device lifetime information through sysfs - First take to slim down the public mmc headers to avoid abuse - Re-factoring of the mmc block device driver to prepare for blkmq - Cleanup code for the mmc block device driver - Clarify and cleanup code dealing with data requests - Cleanup some code by converting to ida_simple_ functions - Cleanup code dealing with card quirks - Cleanup private and public mmc header files MMC host: - Don't rely on public mmc headers to include non-mmc related headers - meson: Add support for eMMC HS400 mode - meson: Various cleanups and improvements - omap_hsmmc: Use the proper provided busy timeout from the core - sunxi: Enable new timings for the A64 MMC controllers - sunxi: Improvements for clock management - tmio: Improvements for SDIO interrupts - mxs-mmc: Add CMD23 support - sdhci-msm: Enable HS400 enhanced strobe mode support - sdhci-msm: Correct HS400 tuning sequence - sdhci-acpi: Support deferred probe - sdhci-pci: Add support for eMMC HS200 tuning mode on AMD - mediatek: Correct the implementation of card busy detection - dw_mmc: Initial support for ZX mmc controller - sh_mobile_sdhi: Enable support for eMMC HS200 mode - sh_mmcif: Various cleanups and improvements" * tag 'mmc-v4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc: (145 commits) mmc: core: add mmc prefix for blk_fixups mmc: core: move all quirks together into quirks.h mmc: core: improve the quirks for sdio devices mmc: core: move some sdio IDs out of quirks file mmc: core: change quirks.c to be a header file mmc: sdhci-cadence: fix bit shift of read data from PHY port mmc: Adding AUTO_BKOPS_EN bit set for Auto BKOPS support mmc: MAN_BKOPS_EN inverse debug message logic mmc: meson-gx: add support for HS400 mode mmc: meson-gx: remove unneeded checks in remove mmc: meson-gx: reduce bounce buffer size mmc: meson-gx: set max block count and request size mmc: meson-gx: improve interrupt handling mmc: meson-gx: improve meson_mmc_irq_thread mmc: meson-gx: improve meson_mmc_clk_set mmc: meson-gx: minor improvements in meson_mmc_set_ios mmc: meson: Assign the minimum clk rate as close to 400KHz as possible mmc: core: start to break apart mmc_start_areq() mmc: block: respect bool returned from blk_end_request() mmc: block: return errorcode from mmc_sd_num_wr_blocks() ...
2017-02-13mmc: queue: turn queue flags into boolsLinus Walleij
Instead of masking and setting two bits in the "flags" field for the mmc_queue, just use two bools named "suspended" and "new_request". The masking and setting would likely have race conditions anyways, it is better to use a simple member like this. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-02-13mmc: core: Move public functions from card.h to private headersUlf Hansson
A significant amount of functions and other definitions are available through the public mmc card.h header file. Let's slim down this public mmc interface, as to prevent users from abusing it, by moving some of the functions/definitions to private mmc header files. This change concentrates on moving the functions into private mmc headers, following changes may continue with additional clean-ups. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
2017-02-13mmc: core: Move public functions from core.h to private headersUlf Hansson
A significant amount of functions are available through the public mmc core.h header file. Let's slim down this public mmc interface, as to prevent users from abusing it, by moving some of the functions to private mmc header files. This change concentrates on moving the functions into private mmc headers, following changes may continue with additional clean-ups, as an example some functions can be turned into static. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
2017-02-13mmc: core: Use kmalloc_array() in mmc_alloc_sg()Markus Elfring
* A multiplication for the size determination of a memory allocation indicated that an array data structure should be processed. Thus use the corresponding function "kmalloc_array". This issue was detected by using the Coccinelle software. * Replace the specification of a data structure by a pointer dereference to make the corresponding size determination a bit safer according to the Linux coding style convention. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-01-31mmc: remove pointless request type check in mmc_prep_requestChristoph Hellwig
The block layer won't send requests the driver isn't asking for, so remove this check. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-12-14Merge tag 'mmc-v4.10-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc Pull another MMC update from Ulf Hansson: "Here's a second pull request for MMC for v4.10. As a matter of fact it's only one change that moves some mmc files around. I thought it was a good idea to get this into v4.10, as it gives us a nice and fresh base for v4.11. Summary: MMC core: - Move files from the card directory to the core directory to enable future clean-ups of the generic mmc header files and interfaces" * tag 'mmc-v4.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc: mmc: block: Move files to core
2016-12-12mmc: block: Move files to coreUlf Hansson
Once upon a time it made sense to keep the mmc block device driver and its related code, in its own directory called card. Over time, more an more functions/structures have become shared through generic mmc header files, between the core and the card directory. In other words, the relationship between them has become closer. By sharing functions/structures via generic header files, it becomes easy for outside users to abuse them. In a way to avoid that from happen, let's move the files from card directory into the core directory, as it enables us to move definitions of functions/structures into mmc core specific header files. Note, this is only the first step in providing a cleaner mmc interface for outside users. Following changes will do the actual cleanup, as that is not part of this change. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>