From 62e24c5775ecb387a3eb33701378ccfa6dbc98ee Mon Sep 17 00:00:00 2001 From: Philipp Zabel Date: Fri, 5 Feb 2016 13:41:39 +0100 Subject: reset: add exported __reset_control_get, return NULL if optional Rename the internal __reset_control_get/put functions to __reset_control_get/put_internal and add an exported __reset_control_get equivalent to __of_reset_control_get that takes a struct device parameter. This avoids the confusing call to __of_reset_control_get in the non-DT case and fixes the devm_reset_control_get_optional function to return NULL if RESET_CONTROLLER is enabled but dev->of_node == NULL. Fixes: bb475230b8e5 ("reset: make optional functions really optional") Reported-by: Andy Shevchenko Tested-by: Andy Shevchenko Cc: Ramiro Oliveira Signed-off-by: Philipp Zabel --- include/linux/reset.h | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) (limited to 'include/linux') diff --git a/include/linux/reset.h b/include/linux/reset.h index 96fb139bdd08..13d8681210d5 100644 --- a/include/linux/reset.h +++ b/include/linux/reset.h @@ -15,6 +15,9 @@ int reset_control_status(struct reset_control *rstc); struct reset_control *__of_reset_control_get(struct device_node *node, const char *id, int index, bool shared, bool optional); +struct reset_control *__reset_control_get(struct device *dev, const char *id, + int index, bool shared, + bool optional); void reset_control_put(struct reset_control *rstc); struct reset_control *__devm_reset_control_get(struct device *dev, const char *id, int index, bool shared, @@ -72,6 +75,13 @@ static inline struct reset_control *__of_reset_control_get( return optional ? NULL : ERR_PTR(-ENOTSUPP); } +static inline struct reset_control *__reset_control_get( + struct device *dev, const char *id, + int index, bool shared, bool optional) +{ + return optional ? NULL : ERR_PTR(-ENOTSUPP); +} + static inline struct reset_control *__devm_reset_control_get( struct device *dev, const char *id, int index, bool shared, bool optional) @@ -102,8 +112,7 @@ __must_check reset_control_get_exclusive(struct device *dev, const char *id) #ifndef CONFIG_RESET_CONTROLLER WARN_ON(1); #endif - return __of_reset_control_get(dev ? dev->of_node : NULL, id, 0, false, - false); + return __reset_control_get(dev, id, 0, false, false); } /** @@ -131,22 +140,19 @@ __must_check reset_control_get_exclusive(struct device *dev, const char *id) static inline struct reset_control *reset_control_get_shared( struct device *dev, const char *id) { - return __of_reset_control_get(dev ? dev->of_node : NULL, id, 0, true, - false); + return __reset_control_get(dev, id, 0, true, false); } static inline struct reset_control *reset_control_get_optional_exclusive( struct device *dev, const char *id) { - return __of_reset_control_get(dev ? dev->of_node : NULL, id, 0, false, - true); + return __reset_control_get(dev, id, 0, false, true); } static inline struct reset_control *reset_control_get_optional_shared( struct device *dev, const char *id) { - return __of_reset_control_get(dev ? dev->of_node : NULL, id, 0, true, - true); + return __reset_control_get(dev, id, 0, true, true); } /** -- cgit v1.2.3 From 5a8d75a1b8c99bdc926ba69b7b7dbe4fae81a5af Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Fri, 14 Apr 2017 13:58:29 -0600 Subject: block: fix bio_will_gap() for first bvec with offset Commit 729204ef49ec("block: relax check on sg gap") allows us to merge bios, if both are physically contiguous. This change can merge a huge number of small bios, through mkfs for example, mkfs.ntfs running time can be decreased to ~1/10. But if one rq starts with a non-aligned buffer (the 1st bvec's bv_offset is non-zero) and if we allow the merge, it is quite difficult to respect sg gap limit, especially the max segment size, or we risk having an unaligned virtual boundary. This patch tries to avoid the issue by disallowing a merge, if the req starts with an unaligned buffer. Also add comments to explain why the merged segment can't end in unaligned virt boundary. Fixes: 729204ef49ec ("block: relax check on sg gap") Tested-by: Johannes Thumshirn Reviewed-by: Johannes Thumshirn Signed-off-by: Ming Lei Rewrote parts of the commit message and comments. Signed-off-by: Jens Axboe --- include/linux/blkdev.h | 32 ++++++++++++++++++++++++++++---- 1 file changed, 28 insertions(+), 4 deletions(-) (limited to 'include/linux') diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 7548f332121a..01a696b0a4d3 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1672,12 +1672,36 @@ static inline bool bios_segs_mergeable(struct request_queue *q, return true; } -static inline bool bio_will_gap(struct request_queue *q, struct bio *prev, - struct bio *next) +static inline bool bio_will_gap(struct request_queue *q, + struct request *prev_rq, + struct bio *prev, + struct bio *next) { if (bio_has_data(prev) && queue_virt_boundary(q)) { struct bio_vec pb, nb; + /* + * don't merge if the 1st bio starts with non-zero + * offset, otherwise it is quite difficult to respect + * sg gap limit. We work hard to merge a huge number of small + * single bios in case of mkfs. + */ + if (prev_rq) + bio_get_first_bvec(prev_rq->bio, &pb); + else + bio_get_first_bvec(prev, &pb); + if (pb.bv_offset) + return true; + + /* + * We don't need to worry about the situation that the + * merged segment ends in unaligned virt boundary: + * + * - if 'pb' ends aligned, the merged segment ends aligned + * - if 'pb' ends unaligned, the next bio must include + * one single bvec of 'nb', otherwise the 'nb' can't + * merge with 'pb' + */ bio_get_last_bvec(prev, &pb); bio_get_first_bvec(next, &nb); @@ -1690,12 +1714,12 @@ static inline bool bio_will_gap(struct request_queue *q, struct bio *prev, static inline bool req_gap_back_merge(struct request *req, struct bio *bio) { - return bio_will_gap(req->q, req->biotail, bio); + return bio_will_gap(req->q, req, req->biotail, bio); } static inline bool req_gap_front_merge(struct request *req, struct bio *bio) { - return bio_will_gap(req->q, bio, req->bio); + return bio_will_gap(req->q, NULL, bio, req->bio); } int kblockd_schedule_work(struct work_struct *work); -- cgit v1.2.3