[PATCH V6 06/12] block: prepare for supporting bio_list via other link
From: Ming Lei <hidden>
Date: 2021-04-22 12:22:44
Also in:
dm-devel
Subsystem:
block layer, the rest · Maintainers:
Jens Axboe, Linus Torvalds
So far bio list helpers always use .bi_next to traverse the list, we will support to link bios by other bio field. Prepare for such support by adding a macro so that users can define another helpers for linking bios by other bio field. Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Ming Lei <redacted> --- include/linux/bio.h | 132 +++++++++++++++++++++++--------------------- 1 file changed, 68 insertions(+), 64 deletions(-)
diff --git a/include/linux/bio.h b/include/linux/bio.h
index a0b4cfdf62a4..c95f0e4fe530 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h@@ -602,75 +602,11 @@ static inline unsigned bio_list_size(const struct bio_list *bl) return sz; } -static inline void bio_list_add(struct bio_list *bl, struct bio *bio) -{ - bio->bi_next = NULL; - - if (bl->tail) - bl->tail->bi_next = bio; - else - bl->head = bio; - - bl->tail = bio; -} - -static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio) -{ - bio->bi_next = bl->head; - - bl->head = bio; - - if (!bl->tail) - bl->tail = bio; -} - -static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2) -{ - if (!bl2->head) - return; - - if (bl->tail) - bl->tail->bi_next = bl2->head; - else - bl->head = bl2->head; - - bl->tail = bl2->tail; -} - -static inline void bio_list_merge_head(struct bio_list *bl, - struct bio_list *bl2) -{ - if (!bl2->head) - return; - - if (bl->head) - bl2->tail->bi_next = bl->head; - else - bl->tail = bl2->tail; - - bl->head = bl2->head; -} - static inline struct bio *bio_list_peek(struct bio_list *bl) { return bl->head; } -static inline struct bio *bio_list_pop(struct bio_list *bl) -{ - struct bio *bio = bl->head; - - if (bio) { - bl->head = bl->head->bi_next; - if (!bl->head) - bl->tail = NULL; - - bio->bi_next = NULL; - } - - return bio; -} - static inline struct bio *bio_list_get(struct bio_list *bl) { struct bio *bio = bl->head;
@@ -680,6 +616,74 @@ static inline struct bio *bio_list_get(struct bio_list *bl) return bio; } +#define BIO_LIST_HELPERS(_pre, link) \ + \ +static inline void _pre##_add(struct bio_list *bl, struct bio *bio) \ +{ \ + bio->bi_##link = NULL; \ + \ + if (bl->tail) \ + bl->tail->bi_##link = bio; \ + else \ + bl->head = bio; \ + \ + bl->tail = bio; \ +} \ + \ +static inline void _pre##_add_head(struct bio_list *bl, struct bio *bio) \ +{ \ + bio->bi_##link = bl->head; \ + \ + bl->head = bio; \ + \ + if (!bl->tail) \ + bl->tail = bio; \ +} \ + \ +static inline void _pre##_merge(struct bio_list *bl, struct bio_list *bl2) \ +{ \ + if (!bl2->head) \ + return; \ + \ + if (bl->tail) \ + bl->tail->bi_##link = bl2->head; \ + else \ + bl->head = bl2->head; \ + \ + bl->tail = bl2->tail; \ +} \ + \ +static inline void _pre##_merge_head(struct bio_list *bl, \ + struct bio_list *bl2) \ +{ \ + if (!bl2->head) \ + return; \ + \ + if (bl->head) \ + bl2->tail->bi_##link = bl->head; \ + else \ + bl->tail = bl2->tail; \ + \ + bl->head = bl2->head; \ +} \ + \ +static inline struct bio *_pre##_pop(struct bio_list *bl) \ +{ \ + struct bio *bio = bl->head; \ + \ + if (bio) { \ + bl->head = bl->head->bi_##link; \ + if (!bl->head) \ + bl->tail = NULL; \ + \ + bio->bi_##link = NULL; \ + } \ + \ + return bio; \ +} \ + +BIO_LIST_HELPERS(bio_list, next); + /* * Increment chain count for the bio. Make sure the CHAIN flag update * is visible before the raised count.
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2.29.2