diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-core.c | 31 |
1 files changed, 14 insertions, 17 deletions
diff --git a/block/blk-core.c b/block/blk-core.c index 718897e6d37..44b6d691728 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1490,9 +1490,9 @@ end_io: /* * We only want one ->make_request_fn to be active at a time, * else stack usage with stacked devices could be a problem. - * So use current->bio_{list,tail} to keep a list of requests + * So use current->bio_list to keep a list of requests * submited by a make_request_fn function. - * current->bio_tail is also used as a flag to say if + * current->bio_list is also used as a flag to say if * generic_make_request is currently active in this task or not. * If it is NULL, then no make_request is active. If it is non-NULL, * then a make_request is active, and new requests should be added @@ -1500,11 +1500,11 @@ end_io: */ void generic_make_request(struct bio *bio) { - if (current->bio_tail) { + struct bio_list bio_list_on_stack; + + if (current->bio_list) { /* make_request is active */ - *(current->bio_tail) = bio; - bio->bi_next = NULL; - current->bio_tail = &bio->bi_next; + bio_list_add(current->bio_list, bio); return; } /* following loop may be a bit non-obvious, and so deserves some @@ -1512,30 +1512,27 @@ void generic_make_request(struct bio *bio) * Before entering the loop, bio->bi_next is NULL (as all callers * ensure that) so we have a list with a single bio. * We pretend that we have just taken it off a longer list, so - * we assign bio_list to the next (which is NULL) and bio_tail - * to &bio_list, thus initialising the bio_list of new bios to be + * we assign bio_list to a pointer to the bio_list_on_stack, + * thus initialising the bio_list of new bios to be * added. __generic_make_request may indeed add some more bios * through a recursive call to generic_make_request. If it * did, we find a non-NULL value in bio_list and re-enter the loop * from the top. In this case we really did just take the bio - * of the top of the list (no pretending) and so fixup bio_list and - * bio_tail or bi_next, and call into __generic_make_request again. + * of the top of the list (no pretending) and so remove it from + * bio_list, and call into __generic_make_request again. * * The loop was structured like this to make only one call to * __generic_make_request (which is important as it is large and * inlined) and to keep the structure simple. */ BUG_ON(bio->bi_next); + bio_list_init(&bio_list_on_stack); + current->bio_list = &bio_list_on_stack; do { - current->bio_list = bio->bi_next; - if (bio->bi_next == NULL) - current->bio_tail = ¤t->bio_list; - else - bio->bi_next = NULL; __generic_make_request(bio); - bio = current->bio_list; + bio = bio_list_pop(current->bio_list); } while (bio); - current->bio_tail = NULL; /* deactivate */ + current->bio_list = NULL; /* deactivate */ } EXPORT_SYMBOL(generic_make_request); |