--- /dev/null
+/*
+ * 2.5 block I/O model
+ *
+ * Copyright (C) 2001 Jens Axboe <axboe@suse.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public Licens
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
+ */
+#ifndef __LINUX_BIO_H
+#define __LINUX_BIO_H
+
+#include <linux/mempool.h>
+#include <linux/bug.h>
+#include <linux/err.h>
+
+#include <linux/blkdev.h>
+#include <linux/blk_types.h>
+#include <linux/workqueue.h>
+
+#define bio_prio(bio) (bio)->bi_ioprio
+#define bio_set_prio(bio, prio) ((bio)->bi_ioprio = prio)
+
+#define bio_iter_iovec(bio, iter) \
+ bvec_iter_bvec((bio)->bi_io_vec, (iter))
+
+#define bio_iter_page(bio, iter) \
+ bvec_iter_page((bio)->bi_io_vec, (iter))
+#define bio_iter_len(bio, iter) \
+ bvec_iter_len((bio)->bi_io_vec, (iter))
+#define bio_iter_offset(bio, iter) \
+ bvec_iter_offset((bio)->bi_io_vec, (iter))
+
+#define bio_page(bio) bio_iter_page((bio), (bio)->bi_iter)
+#define bio_offset(bio) bio_iter_offset((bio), (bio)->bi_iter)
+#define bio_iovec(bio) bio_iter_iovec((bio), (bio)->bi_iter)
+
+#define bio_multiple_segments(bio) \
+ ((bio)->bi_iter.bi_size != bio_iovec(bio).bv_len)
+
+#define bvec_iter_sectors(iter) ((iter).bi_size >> 9)
+#define bvec_iter_end_sector(iter) ((iter).bi_sector + bvec_iter_sectors((iter)))
+
+#define bio_sectors(bio) bvec_iter_sectors((bio)->bi_iter)
+#define bio_end_sector(bio) bvec_iter_end_sector((bio)->bi_iter)
+
+static inline bool bio_has_data(struct bio *bio)
+{
+ if (bio &&
+ bio->bi_iter.bi_size &&
+ bio_op(bio) != REQ_OP_DISCARD &&
+ bio_op(bio) != REQ_OP_SECURE_ERASE)
+ return true;
+
+ return false;
+}
+
+static inline bool bio_no_advance_iter(struct bio *bio)
+{
+ return bio_op(bio) == REQ_OP_DISCARD ||
+ bio_op(bio) == REQ_OP_SECURE_ERASE ||
+ bio_op(bio) == REQ_OP_WRITE_SAME;
+}
+
+static inline bool bio_is_rw(struct bio *bio)
+{
+ if (!bio_has_data(bio))
+ return false;
+
+ if (bio_no_advance_iter(bio))
+ return false;
+
+ return true;
+}
+
+static inline bool bio_mergeable(struct bio *bio)
+{
+ if (bio->bi_opf & REQ_NOMERGE_FLAGS)
+ return false;
+
+ return true;
+}
+
+static inline unsigned int bio_cur_bytes(struct bio *bio)
+{
+ if (bio_has_data(bio))
+ return bio_iovec(bio).bv_len;
+ else /* dataless requests such as discard */
+ return bio->bi_iter.bi_size;
+}
+
+static inline void *bio_data(struct bio *bio)
+{
+ if (bio_has_data(bio))
+ return page_address(bio_page(bio)) + bio_offset(bio);
+
+ return NULL;
+}
+
+#define __bio_kmap_atomic(bio, iter) \
+ (kmap_atomic(bio_iter_iovec((bio), (iter)).bv_page) + \
+ bio_iter_iovec((bio), (iter)).bv_offset)
+
+#define __bio_kunmap_atomic(addr) kunmap_atomic(addr)
+
+static inline struct bio_vec *bio_next_segment(const struct bio *bio,
+ struct bvec_iter_all *iter)
+{
+ if (iter->idx >= bio->bi_vcnt)
+ return NULL;
+
+ return &bio->bi_io_vec[iter->idx];
+}
+
+#define bio_for_each_segment_all(bvl, bio, iter) \
+ for ((iter).idx = 0; (bvl = bio_next_segment((bio), &(iter))); (iter).idx++)
+
+static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
+ unsigned bytes)
+{
+ iter->bi_sector += bytes >> 9;
+
+ if (bio_no_advance_iter(bio))
+ iter->bi_size -= bytes;
+ else
+ bvec_iter_advance(bio->bi_io_vec, iter, bytes);
+}
+
+#define __bio_for_each_segment(bvl, bio, iter, start) \
+ for (iter = (start); \
+ (iter).bi_size && \
+ ((bvl = bio_iter_iovec((bio), (iter))), 1); \
+ bio_advance_iter((bio), &(iter), (bvl).bv_len))
+
+#define bio_for_each_segment(bvl, bio, iter) \
+ __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
+
+#define __bio_for_each_bvec(bvl, bio, iter, start) \
+ __bio_for_each_segment(bvl, bio, iter, start)
+
+#define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
+
+static inline unsigned bio_segments(struct bio *bio)
+{
+ unsigned segs = 0;
+ struct bio_vec bv;
+ struct bvec_iter iter;
+
+ /*
+ * We special case discard/write same, because they interpret bi_size
+ * differently:
+ */
+
+ if (bio_op(bio) == REQ_OP_DISCARD)
+ return 1;
+
+ if (bio_op(bio) == REQ_OP_SECURE_ERASE)
+ return 1;
+
+ if (bio_op(bio) == REQ_OP_WRITE_SAME)
+ return 1;
+
+ bio_for_each_segment(bv, bio, iter)
+ segs++;
+
+ return segs;
+}
+
+static inline void bio_get(struct bio *bio)
+{
+ bio->bi_flags |= (1 << BIO_REFFED);
+ smp_mb__before_atomic();
+ atomic_inc(&bio->__bi_cnt);
+}
+
+static inline bool bio_flagged(struct bio *bio, unsigned int bit)
+{
+ return (bio->bi_flags & (1U << bit)) != 0;
+}
+
+static inline void bio_set_flag(struct bio *bio, unsigned int bit)
+{
+ bio->bi_flags |= (1U << bit);
+}
+
+static inline void bio_clear_flag(struct bio *bio, unsigned int bit)
+{
+ bio->bi_flags &= ~(1U << bit);
+}
+
+extern struct bio *bio_split(struct bio *bio, int sectors,
+ gfp_t gfp, struct bio_set *bs);
+
+static inline struct bio *bio_next_split(struct bio *bio, int sectors,
+ gfp_t gfp, struct bio_set *bs)
+{
+ if (sectors >= bio_sectors(bio))
+ return bio;
+
+ return bio_split(bio, sectors, gfp, bs);
+}
+
+struct bio_set {
+ unsigned int front_pad;
+ unsigned int back_pad;
+ mempool_t bio_pool;
+ mempool_t bvec_pool;
+};
+
+
+static inline void bioset_free(struct bio_set *bs)
+{
+ kfree(bs);
+}
+
+void bioset_exit(struct bio_set *);
+int bioset_init(struct bio_set *, unsigned, unsigned, int);
+
+extern struct bio_set *bioset_create(unsigned int, unsigned int);
+extern struct bio_set *bioset_create_nobvec(unsigned int, unsigned int);
+enum {
+ BIOSET_NEED_BVECS = 1 << 0,
+ BIOSET_NEED_RESCUER = 1 << 1,
+};
+
+struct bio *bio_alloc_bioset(struct block_device *, unsigned,
+ blk_opf_t, gfp_t, struct bio_set *);
+extern void bio_put(struct bio *);
+
+int bio_add_page(struct bio *, struct page *, unsigned, unsigned);
+
+struct bio *bio_alloc_clone(struct block_device *, struct bio *,
+ gfp_t, struct bio_set *);
+
+struct bio *bio_kmalloc(unsigned int, gfp_t);
+
+extern void bio_endio(struct bio *);
+
+extern void bio_advance(struct bio *, unsigned);
+
+extern void bio_reset(struct bio *, struct block_device *, unsigned);
+void bio_chain(struct bio *, struct bio *);
+
+extern void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter,
+ struct bio *src, struct bvec_iter *src_iter);
+extern void bio_copy_data(struct bio *dst, struct bio *src);
+
+void bio_free_pages(struct bio *bio);
+
+void zero_fill_bio_iter(struct bio *bio, struct bvec_iter iter);
+
+static inline void zero_fill_bio(struct bio *bio)
+{
+ zero_fill_bio_iter(bio, bio->bi_iter);
+}
+
+#define bio_set_dev(bio, bdev) \
+do { \
+ (bio)->bi_bdev = (bdev); \
+} while (0)
+
+#define bio_copy_dev(dst, src) \
+do { \
+ (dst)->bi_bdev = (src)->bi_bdev; \
+} while (0)
+
+static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
+{
+ return page_address(bvec->bv_page) + bvec->bv_offset;
+}
+
+static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
+{
+ *flags = 0;
+}
+
+static inline char *__bio_kmap_irq(struct bio *bio, struct bvec_iter iter,
+ unsigned long *flags)
+{
+ return bvec_kmap_irq(&bio_iter_iovec(bio, iter), flags);
+}
+#define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
+
+#define bio_kmap_irq(bio, flags) \
+ __bio_kmap_irq((bio), (bio)->bi_iter, (flags))
+#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
+
+struct bio_list {
+ struct bio *head;
+ struct bio *tail;
+};
+
+static inline int bio_list_empty(const struct bio_list *bl)
+{
+ return bl->head == NULL;
+}
+
+static inline void bio_list_init(struct bio_list *bl)
+{
+ bl->head = bl->tail = NULL;
+}
+
+#define BIO_EMPTY_LIST { NULL, NULL }
+
+#define bio_list_for_each(bio, bl) \
+ for (bio = (bl)->head; bio; bio = bio->bi_next)
+
+static inline unsigned bio_list_size(const struct bio_list *bl)
+{
+ unsigned sz = 0;
+ struct bio *bio;
+
+ bio_list_for_each(bio, bl)
+ sz++;
+
+ 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;
+
+ bl->head = bl->tail = NULL;
+
+ return bio;
+}
+
+/*
+ * Increment chain count for the bio. Make sure the CHAIN flag update
+ * is visible before the raised count.
+ */
+static inline void bio_inc_remaining(struct bio *bio)
+{
+ bio_set_flag(bio, BIO_CHAIN);
+ smp_mb__before_atomic();
+ atomic_inc(&bio->__bi_remaining);
+}
+
+static inline void bio_init(struct bio *bio,
+ struct block_device *bdev,
+ struct bio_vec *table,
+ unsigned short max_vecs,
+ unsigned int opf)
+{
+ memset(bio, 0, sizeof(*bio));
+ bio->bi_bdev = bdev;
+ bio->bi_opf = opf;
+ atomic_set(&bio->__bi_remaining, 1);
+ atomic_set(&bio->__bi_cnt, 1);
+
+ bio->bi_io_vec = table;
+ bio->bi_max_vecs = max_vecs;
+}
+
+#endif /* __LINUX_BIO_H */
projects / bcachefs-tools-debian / blobdiff