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| author | Mike Snitzer <snitzer@redhat.com> | 2015-06-26 17:01:13 +0300 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2015-06-26 17:11:58 +0300 |
| commit | 78d8e58a086b214dddf1fd463e20a7e1d82d7866 (patch) | |
| tree | 2868b9a09eb82b8ecf37ec96fc494838dfdee63a /include | |
| parent | 4e6e36c3714364b65f2bfea8c73691c663891726 (diff) | |
| download | linux-78d8e58a086b214dddf1fd463e20a7e1d82d7866.tar.xz | |
Revert "block, dm: don't copy bios for request clones"
This reverts commit 5f1b670d0bef508a5554d92525f5f6d00d640b38.
Justification for revert as reported in this dm-devel post:
https://www.redhat.com/archives/dm-devel/2015-June/msg00160.html
this change should not be pushed to mainline yet.
Firstly, Christoph has a newer version of the patch that fixes silent
data corruption problem:
https://www.redhat.com/archives/dm-devel/2015-May/msg00229.html
And the new version still depends on LLDDs to always complete requests
to the end when error happens, while block API doesn't enforce such a
requirement. If the assumption is ever broken, the inconsistency between
request and bio (e.g. rq->__sector and rq->bio) will cause silent data
corruption:
https://www.redhat.com/archives/dm-devel/2015-June/msg00022.html
Reported-by: Junichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/blk_types.h | 2 | ||||
| -rw-r--r-- | include/linux/blkdev.h | 6 |
2 files changed, 5 insertions, 3 deletions
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 6ab9d12d1f17..7303b3405520 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -192,7 +192,6 @@ enum rq_flag_bits { __REQ_HASHED, /* on IO scheduler merge hash */ __REQ_MQ_INFLIGHT, /* track inflight for MQ */ __REQ_NO_TIMEOUT, /* requests may never expire */ - __REQ_CLONE, /* cloned bios */ __REQ_NR_BITS, /* stops here */ }; @@ -247,6 +246,5 @@ enum rq_flag_bits { #define REQ_HASHED (1ULL << __REQ_HASHED) #define REQ_MQ_INFLIGHT (1ULL << __REQ_MQ_INFLIGHT) #define REQ_NO_TIMEOUT (1ULL << __REQ_NO_TIMEOUT) -#define REQ_CLONE (1ULL << __REQ_CLONE) #endif /* __LINUX_BLK_TYPES_H */ diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 776d2ee43ba6..41c0fb573dff 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -775,7 +775,11 @@ extern void blk_add_request_payload(struct request *rq, struct page *page, unsigned int len); extern int blk_rq_check_limits(struct request_queue *q, struct request *rq); extern int blk_lld_busy(struct request_queue *q); -extern void blk_rq_prep_clone(struct request *rq, struct request *rq_src); +extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src, + struct bio_set *bs, gfp_t gfp_mask, + int (*bio_ctr)(struct bio *, struct bio *, void *), + void *data); +extern void blk_rq_unprep_clone(struct request *rq); extern int blk_insert_cloned_request(struct request_queue *q, struct request *rq); extern void blk_delay_queue(struct request_queue *, unsigned long); |