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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 08:07:57 -06:00
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef MMC_QUEUE_H
#define MMC_QUEUE_H
#include <linux/types.h>
#include <linux/blkdev.h>
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>
2017-05-18 03:29:32 -06:00
#include <linux/blk-mq.h>
#include <linux/mmc/core.h>
#include <linux/mmc/host.h>
enum mmc_issued {
MMC_REQ_STARTED,
MMC_REQ_BUSY,
MMC_REQ_FAILED_TO_START,
MMC_REQ_FINISHED,
};
enum mmc_issue_type {
MMC_ISSUE_SYNC,
MMC_ISSUE_DCMD,
MMC_ISSUE_ASYNC,
MMC_ISSUE_MAX,
};
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>
2017-05-18 03:29:32 -06:00
static inline struct mmc_queue_req *req_to_mmc_queue_req(struct request *rq)
{
return blk_mq_rq_to_pdu(rq);
}
struct mmc_queue_req;
static inline struct request *mmc_queue_req_to_req(struct mmc_queue_req *mqr)
{
return blk_mq_rq_from_pdu(mqr);
}
struct mmc_blk_data;
mmc: block: move single ioctl() commands to block requests 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. We refactor the if/else/if/else ladder in mmc_blk_issue_rq() as part of the job, keeping some extra attention to the case when a NULL req is passed into this function and making that pipeline flush more explicit. Tested on the ux500 with the userspace: mmc extcsd read /dev/mmcblk3 resulting in a successful EXTCSD info dump back to the console. This commit fixes a starvation issue in the MMC/SD stack that can be easily provoked in the following way by issueing the following commands in sequence: > dd if=/dev/mmcblk3 of=/dev/null bs=1M & > mmc extcs read /dev/mmcblk3 Before this patch, the extcsd read command would hang (starve) while waiting for the dd command to finish since the block layer was holding the card/host lock. After this patch, the extcsd ioctl() command is nicely interpersed with the rest of the block commands and we can issue a bunch of ioctl()s from userspace while there is some busy block IO going on without any problems. Conversely userspace ioctl()s can no longer starve the block layer by holding the card/host lock. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Avri Altman <Avri.Altman@sandisk.com>
2017-05-18 03:29:34 -06:00
struct mmc_blk_ioc_data;
struct mmc_blk_request {
struct mmc_request mrq;
struct mmc_command sbc;
struct mmc_command cmd;
struct mmc_command stop;
struct mmc_data data;
};
/**
* enum mmc_drv_op - enumerates the operations in the mmc_queue_req
* @MMC_DRV_OP_IOCTL: ioctl operation
mmc: block: Convert RPMB to a character device The RPMB partition on the eMMC devices is a special area used for storing cryptographically safe information signed by a special secret key. To write and read records from this special area, authentication is needed. The RPMB area is *only* and *exclusively* accessed using ioctl():s from userspace. It is not really a block device, as blocks cannot be read or written from the device, also the signed chunks that can be stored on the RPMB are actually 256 bytes, not 512 making a block device a real bad fit. Currently the RPMB partition spawns a separate block device named /dev/mmcblkNrpmb for each device with an RPMB partition, including the creation of a block queue with its own kernel thread and all overhead associated with this. On the Ux500 HREFv60 platform, for example, the two eMMCs means that two block queues with separate threads are created for no use whatsoever. I have concluded that this block device design for RPMB is actually pretty wrong. The RPMB area should have been designed to be accessed from /dev/mmcblkN directly, using ioctl()s on the main block device. It is however way too late to change that, since userspace expects to open an RPMB device in /dev/mmcblkNrpmb and we cannot break userspace. This patch tries to amend the situation using the following strategy: - Stop creating a block device for the RPMB partition/area - Instead create a custom, dynamic character device with the same name. - Make this new character device support exactly the same set of ioctl()s as the old block device. - Wrap the requests back to the same ioctl() handlers, but issue them on the block queue of the main partition/area, i.e. /dev/mmcblkN We need to create a special "rpmb" bus type in order to get udev and/or busybox hot/coldplug to instantiate the device node properly. Before the patch, this appears in 'ps aux': 101 root 0:00 [mmcqd/2rpmb] 123 root 0:00 [mmcqd/3rpmb] After applying the patch these surplus block queue threads are gone, but RPMB is as usable as ever using the userspace MMC tools, such as 'mmc rpmb read-counter'. We get instead those dynamice devices in /dev: brw-rw---- 1 root root 179, 0 Jan 1 2000 mmcblk0 brw-rw---- 1 root root 179, 1 Jan 1 2000 mmcblk0p1 brw-rw---- 1 root root 179, 2 Jan 1 2000 mmcblk0p2 brw-rw---- 1 root root 179, 5 Jan 1 2000 mmcblk0p5 brw-rw---- 1 root root 179, 8 Jan 1 2000 mmcblk2 brw-rw---- 1 root root 179, 16 Jan 1 2000 mmcblk2boot0 brw-rw---- 1 root root 179, 24 Jan 1 2000 mmcblk2boot1 crw-rw---- 1 root root 248, 0 Jan 1 2000 mmcblk2rpmb brw-rw---- 1 root root 179, 32 Jan 1 2000 mmcblk3 brw-rw---- 1 root root 179, 40 Jan 1 2000 mmcblk3boot0 brw-rw---- 1 root root 179, 48 Jan 1 2000 mmcblk3boot1 brw-rw---- 1 root root 179, 33 Jan 1 2000 mmcblk3p1 crw-rw---- 1 root root 248, 1 Jan 1 2000 mmcblk3rpmb Notice the (248,0) and (248,1) character devices for RPMB. 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>
2017-09-20 02:02:00 -06:00
* @MMC_DRV_OP_IOCTL_RPMB: RPMB-oriented ioctl operation
* @MMC_DRV_OP_BOOT_WP: write protect boot partitions
* @MMC_DRV_OP_GET_CARD_STATUS: get card status
* @MMC_DRV_OP_GET_EXT_CSD: get the EXT CSD from an eMMC card
*/
enum mmc_drv_op {
MMC_DRV_OP_IOCTL,
mmc: block: Convert RPMB to a character device The RPMB partition on the eMMC devices is a special area used for storing cryptographically safe information signed by a special secret key. To write and read records from this special area, authentication is needed. The RPMB area is *only* and *exclusively* accessed using ioctl():s from userspace. It is not really a block device, as blocks cannot be read or written from the device, also the signed chunks that can be stored on the RPMB are actually 256 bytes, not 512 making a block device a real bad fit. Currently the RPMB partition spawns a separate block device named /dev/mmcblkNrpmb for each device with an RPMB partition, including the creation of a block queue with its own kernel thread and all overhead associated with this. On the Ux500 HREFv60 platform, for example, the two eMMCs means that two block queues with separate threads are created for no use whatsoever. I have concluded that this block device design for RPMB is actually pretty wrong. The RPMB area should have been designed to be accessed from /dev/mmcblkN directly, using ioctl()s on the main block device. It is however way too late to change that, since userspace expects to open an RPMB device in /dev/mmcblkNrpmb and we cannot break userspace. This patch tries to amend the situation using the following strategy: - Stop creating a block device for the RPMB partition/area - Instead create a custom, dynamic character device with the same name. - Make this new character device support exactly the same set of ioctl()s as the old block device. - Wrap the requests back to the same ioctl() handlers, but issue them on the block queue of the main partition/area, i.e. /dev/mmcblkN We need to create a special "rpmb" bus type in order to get udev and/or busybox hot/coldplug to instantiate the device node properly. Before the patch, this appears in 'ps aux': 101 root 0:00 [mmcqd/2rpmb] 123 root 0:00 [mmcqd/3rpmb] After applying the patch these surplus block queue threads are gone, but RPMB is as usable as ever using the userspace MMC tools, such as 'mmc rpmb read-counter'. We get instead those dynamice devices in /dev: brw-rw---- 1 root root 179, 0 Jan 1 2000 mmcblk0 brw-rw---- 1 root root 179, 1 Jan 1 2000 mmcblk0p1 brw-rw---- 1 root root 179, 2 Jan 1 2000 mmcblk0p2 brw-rw---- 1 root root 179, 5 Jan 1 2000 mmcblk0p5 brw-rw---- 1 root root 179, 8 Jan 1 2000 mmcblk2 brw-rw---- 1 root root 179, 16 Jan 1 2000 mmcblk2boot0 brw-rw---- 1 root root 179, 24 Jan 1 2000 mmcblk2boot1 crw-rw---- 1 root root 248, 0 Jan 1 2000 mmcblk2rpmb brw-rw---- 1 root root 179, 32 Jan 1 2000 mmcblk3 brw-rw---- 1 root root 179, 40 Jan 1 2000 mmcblk3boot0 brw-rw---- 1 root root 179, 48 Jan 1 2000 mmcblk3boot1 brw-rw---- 1 root root 179, 33 Jan 1 2000 mmcblk3p1 crw-rw---- 1 root root 248, 1 Jan 1 2000 mmcblk3rpmb Notice the (248,0) and (248,1) character devices for RPMB. 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>
2017-09-20 02:02:00 -06:00
MMC_DRV_OP_IOCTL_RPMB,
MMC_DRV_OP_BOOT_WP,
MMC_DRV_OP_GET_CARD_STATUS,
MMC_DRV_OP_GET_EXT_CSD,
};
struct mmc_queue_req {
struct mmc_blk_request brq;
struct scatterlist *sg;
enum mmc_drv_op drv_op;
int drv_op_result;
void *drv_op_data;
unsigned int ioc_count;
int retries;
};
struct mmc_queue {
struct mmc_card *card;
spinlock_t *lock;
struct mmc_ctx ctx;
struct blk_mq_tag_set tag_set;
struct mmc_blk_data *blkdata;
struct request_queue *queue;
int in_flight[MMC_ISSUE_MAX];
unsigned int cqe_busy;
#define MMC_CQE_DCMD_BUSY BIT(0)
#define MMC_CQE_QUEUE_FULL BIT(1)
bool busy;
bool use_cqe;
bool recovery_needed;
bool in_recovery;
bool rw_wait;
bool waiting;
struct work_struct recovery_work;
wait_queue_head_t wait;
struct request *recovery_req;
struct request *complete_req;
struct mutex complete_lock;
struct work_struct complete_work;
};
extern int mmc_init_queue(struct mmc_queue *, struct mmc_card *, spinlock_t *);
extern void mmc_cleanup_queue(struct mmc_queue *);
extern void mmc_queue_suspend(struct mmc_queue *);
extern void mmc_queue_resume(struct mmc_queue *);
extern unsigned int mmc_queue_map_sg(struct mmc_queue *,
struct mmc_queue_req *);
void mmc_cqe_check_busy(struct mmc_queue *mq);
void mmc_cqe_recovery_notifier(struct mmc_request *mrq);
enum mmc_issue_type mmc_issue_type(struct mmc_queue *mq, struct request *req);
static inline int mmc_tot_in_flight(struct mmc_queue *mq)
{
return mq->in_flight[MMC_ISSUE_SYNC] +
mq->in_flight[MMC_ISSUE_DCMD] +
mq->in_flight[MMC_ISSUE_ASYNC];
}
static inline int mmc_cqe_qcnt(struct mmc_queue *mq)
{
return mq->in_flight[MMC_ISSUE_DCMD] +
mq->in_flight[MMC_ISSUE_ASYNC];
}
#endif