This is bio layer functionality and not related to buffer heads.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
block/bio.c | 43 +++++++++++++++++++++++++++++++++++++++++++
fs/buffer.c | 43 -------------------------------------------
fs/internal.h | 1 -
include/linux/bio.h | 1 +
4 files changed, 44 insertions(+), 44 deletions(-)
diff --git a/block/bio.c b/block/bio.c
index 209715765a7a..28d8055c04e2 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -588,6 +588,49 @@ void bio_truncate(struct bio *bio, unsigned new_size)
bio->bi_iter.bi_size = new_size;
}
+/**
+ * guard_bio_eod - truncate a BIO to fit the block device
+ * @bio: bio to truncate
+ *
+ * This allows us to do IO even on the odd last sectors of a device, even if the
+ * block size is some multiple of the physical sector size.
+ *
+ * We'll just truncate the bio to the size of the device, and clear the end of
+ * the buffer head manually. Truly out-of-range accesses will turn into actual
+ * I/O errors, this only handles the "we need to be able to do I/O at the final
+ * sector" case.
+ */
+void guard_bio_eod(struct bio *bio)
+{
+ sector_t maxsector;
+ struct hd_struct *part;
+
+ rcu_read_lock();
+ part = __disk_get_part(bio->bi_disk, bio->bi_partno);
+ if (part)
+ maxsector = part_nr_sects_read(part);
+ else
+ maxsector = get_capacity(bio->bi_disk);
+ rcu_read_unlock();
+
+ if (!maxsector)
+ return;
+
+ /*
+ * If the *whole* IO is past the end of the device,
+ * let it through, and the IO layer will turn it into
+ * an EIO.
+ */
+ if (unlikely(bio->bi_iter.bi_sector >= maxsector))
+ return;
+
+ maxsector -= bio->bi_iter.bi_sector;
+ if (likely((bio->bi_iter.bi_size >> 9) <= maxsector))
+ return;
+
+ bio_truncate(bio, maxsector << 9);
+}
+
/**
* bio_put - release a reference to a bio
* @bio: bio to release reference to
diff --git a/fs/buffer.c b/fs/buffer.c
index b8d28370cfd7..3f5758e01e40 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -3019,49 +3019,6 @@ static void end_bio_bh_io_sync(struct bio *bio)
bio_put(bio);
}
-/*
- * This allows us to do IO even on the odd last sectors
- * of a device, even if the block size is some multiple
- * of the physical sector size.
- *
- * We'll just truncate the bio to the size of the device,
- * and clear the end of the buffer head manually.
- *
- * Truly out-of-range accesses will turn into actual IO
- * errors, this only handles the "we need to be able to
- * do IO at the final sector" case.
- */
-void guard_bio_eod(struct bio *bio)
-{
- sector_t maxsector;
- struct hd_struct *part;
-
- rcu_read_lock();
- part = __disk_get_part(bio->bi_disk, bio->bi_partno);
- if (part)
- maxsector = part_nr_sects_read(part);
- else
- maxsector = get_capacity(bio->bi_disk);
- rcu_read_unlock();
-
- if (!maxsector)
- return;
-
- /*
- * If the *whole* IO is past the end of the device,
- * let it through, and the IO layer will turn it into
- * an EIO.
- */
- if (unlikely(bio->bi_iter.bi_sector >= maxsector))
- return;
-
- maxsector -= bio->bi_iter.bi_sector;
- if (likely((bio->bi_iter.bi_size >> 9) <= maxsector))
- return;
-
- bio_truncate(bio, maxsector << 9);
-}
-
static int submit_bh_wbc(int op, int op_flags, struct buffer_head *bh,
enum rw_hint write_hint, struct writeback_control *wbc)
{
diff --git a/fs/internal.h b/fs/internal.h
index f3f280b952a3..4d37912a5587 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -38,7 +38,6 @@ static inline int __sync_blockdev(struct block_device *bdev, int wait)
/*
* buffer.c
*/
-extern void guard_bio_eod(struct bio *bio);
extern int __block_write_begin_int(struct page *page, loff_t pos, unsigned len,
get_block_t *get_block, struct iomap *iomap);
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 853d92ceee64..a430e9c1c2d2 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -471,6 +471,7 @@ extern struct bio *bio_copy_user_iov(struct request_queue *,
extern int bio_uncopy_user(struct bio *);
void zero_fill_bio_iter(struct bio *bio, struct bvec_iter iter);
void bio_truncate(struct bio *bio, unsigned new_size);
+void guard_bio_eod(struct bio *bio);
static inline void zero_fill_bio(struct bio *bio)
{
--
2.25.1
