diff options
| author | Ming Lei <ming.lei@redhat.com> | 2017-12-18 20:22:07 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2018-01-06 09:18:00 -0700 |
| commit | 3c892a098b0bfa3e571f1f0d2a7e72fbaeea691a (patch) | |
| tree | 93a2f8c318cf22449587d8c3e9a1df6d52a4cc10 | |
| parent | 7891f05cbf4944a5436491d66de2be7533089aea (diff) | |
block: bounce: don't access bio->bi_io_vec in copy_to_high_bio_irq
Firstly this patch introduces BVEC_ITER_ALL_INIT for iterating one bio
from start to end.
As we need to support multipage bvecs, don't access bio->bi_io_vec
in copy_to_high_bio_irq(), and just use the standard iterator for that.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | block/bounce.c | 16 | ||||
| -rw-r--r-- | include/linux/bvec.h | 9 |
2 files changed, 20 insertions, 5 deletions
diff --git a/block/bounce.c b/block/bounce.c index 0274c31d6c05..c35a3d7f0528 100644 --- a/block/bounce.c +++ b/block/bounce.c @@ -113,24 +113,30 @@ int init_emergency_isa_pool(void) static void copy_to_high_bio_irq(struct bio *to, struct bio *from) { unsigned char *vfrom; - struct bio_vec tovec, *fromvec = from->bi_io_vec; + struct bio_vec tovec, fromvec; struct bvec_iter iter; + /* + * The bio of @from is created by bounce, so we can iterate + * its bvec from start to end, but the @from->bi_iter can't be + * trusted because it might be changed by splitting. + */ + struct bvec_iter from_iter = BVEC_ITER_ALL_INIT; bio_for_each_segment(tovec, to, iter) { - if (tovec.bv_page != fromvec->bv_page) { + fromvec = bio_iter_iovec(from, from_iter); + if (tovec.bv_page != fromvec.bv_page) { /* * fromvec->bv_offset and fromvec->bv_len might have * been modified by the block layer, so use the original * copy, bounce_copy_vec already uses tovec->bv_len */ - vfrom = page_address(fromvec->bv_page) + + vfrom = page_address(fromvec.bv_page) + tovec.bv_offset; bounce_copy_vec(&tovec, vfrom); flush_dcache_page(tovec.bv_page); } - - fromvec++; + bio_advance_iter(from, &from_iter, tovec.bv_len); } } diff --git a/include/linux/bvec.h b/include/linux/bvec.h index ec8a4d7af6bd..fe7a22dd133b 100644 --- a/include/linux/bvec.h +++ b/include/linux/bvec.h @@ -125,4 +125,13 @@ static inline bool bvec_iter_rewind(const struct bio_vec *bv, ((bvl = bvec_iter_bvec((bio_vec), (iter))), 1); \ bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len)) +/* for iterating one bio from start to end */ +#define BVEC_ITER_ALL_INIT (struct bvec_iter) \ +{ \ + .bi_sector = 0, \ + .bi_size = UINT_MAX, \ + .bi_idx = 0, \ + .bi_bvec_done = 0, \ +} + #endif /* __LINUX_BVEC_ITER_H */ |