diff options
Diffstat (limited to 'block/bio.c')
-rw-r--r-- | block/bio.c | 59 |
1 files changed, 32 insertions, 27 deletions
diff --git a/block/bio.c b/block/bio.c index dbabd48b1934..f124a0a624fc 100644 --- a/block/bio.c +++ b/block/bio.c @@ -296,13 +296,19 @@ void bio_reset(struct bio *bio) } EXPORT_SYMBOL(bio_reset); -static void bio_chain_endio(struct bio *bio) +static struct bio *__bio_chain_endio(struct bio *bio) { struct bio *parent = bio->bi_private; - parent->bi_error = bio->bi_error; - bio_endio(parent); + if (!parent->bi_error) + parent->bi_error = bio->bi_error; bio_put(bio); + return parent; +} + +static void bio_chain_endio(struct bio *bio) +{ + bio_endio(__bio_chain_endio(bio)); } /* @@ -874,7 +880,7 @@ int submit_bio_wait(int rw, struct bio *bio) bio->bi_private = &ret; bio->bi_end_io = submit_bio_wait_endio; submit_bio(rw, bio); - wait_for_completion(&ret.event); + wait_for_completion_io(&ret.event); return ret.error; } @@ -1090,9 +1096,12 @@ int bio_uncopy_user(struct bio *bio) if (!bio_flagged(bio, BIO_NULL_MAPPED)) { /* * if we're in a workqueue, the request is orphaned, so - * don't copy into a random user address space, just free. + * don't copy into a random user address space, just free + * and return -EINTR so user space doesn't expect any data. */ - if (current->mm && bio_data_dir(bio) == READ) + if (!current->mm) + ret = -EINTR; + else if (bio_data_dir(bio) == READ) ret = bio_copy_to_iter(bio, bmd->iter); if (bmd->is_our_pages) bio_free_pages(bio); @@ -1739,29 +1748,25 @@ static inline bool bio_remaining_done(struct bio *bio) **/ void bio_endio(struct bio *bio) { - while (bio) { - if (unlikely(!bio_remaining_done(bio))) - break; +again: + if (!bio_remaining_done(bio)) + return; - /* - * Need to have a real endio function for chained bios, - * otherwise various corner cases will break (like stacking - * block devices that save/restore bi_end_io) - however, we want - * to avoid unbounded recursion and blowing the stack. Tail call - * optimization would handle this, but compiling with frame - * pointers also disables gcc's sibling call optimization. - */ - if (bio->bi_end_io == bio_chain_endio) { - struct bio *parent = bio->bi_private; - parent->bi_error = bio->bi_error; - bio_put(bio); - bio = parent; - } else { - if (bio->bi_end_io) - bio->bi_end_io(bio); - bio = NULL; - } + /* + * Need to have a real endio function for chained bios, otherwise + * various corner cases will break (like stacking block devices that + * save/restore bi_end_io) - however, we want to avoid unbounded + * recursion and blowing the stack. Tail call optimization would + * handle this, but compiling with frame pointers also disables + * gcc's sibling call optimization. + */ + if (bio->bi_end_io == bio_chain_endio) { + bio = __bio_chain_endio(bio); + goto again; } + + if (bio->bi_end_io) + bio->bi_end_io(bio); } EXPORT_SYMBOL(bio_endio); |