diff options
author | Al Viro <viro@zeniv.linux.org.uk> | 2014-04-05 07:12:29 +0400 |
---|---|---|
committer | Al Viro <viro@zeniv.linux.org.uk> | 2014-05-07 01:39:45 +0400 |
commit | 62a8067a7f35dba2de501c9cb00e4cf36da90bc0 (patch) | |
tree | bb008456891c13b9d8a25825a10074efb861cd88 /include | |
parent | 81055e584f9d743cb13dc7944923d817c20f089d (diff) | |
download | linux-62a8067a7f35dba2de501c9cb00e4cf36da90bc0.tar.xz |
bio_vec-backed iov_iter
New variant of iov_iter - ITER_BVEC in iter->type, backed with
bio_vec array instead of iovec one. Primitives taught to deal
with such beasts, __swap_write() switched to using that kind
of iov_iter.
Note that bio_vec is just a <page, offset, length> triple - there's
nothing block-specific about it. I've left the definition where it
was, but took it from under ifdef CONFIG_BLOCK.
Next target: ->splice_write()...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/blk_types.h | 4 | ||||
-rw-r--r-- | include/linux/uio.h | 14 |
2 files changed, 14 insertions, 4 deletions
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index aa0eaa2d0bd8..86df13b97160 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -5,8 +5,6 @@ #ifndef __LINUX_BLK_TYPES_H #define __LINUX_BLK_TYPES_H -#ifdef CONFIG_BLOCK - #include <linux/types.h> struct bio_set; @@ -28,6 +26,8 @@ struct bio_vec { unsigned int bv_offset; }; +#ifdef CONFIG_BLOCK + struct bvec_iter { sector_t bi_sector; /* device address in 512 byte sectors */ diff --git a/include/linux/uio.h b/include/linux/uio.h index e8a109a75de1..e2231e47cec1 100644 --- a/include/linux/uio.h +++ b/include/linux/uio.h @@ -19,12 +19,21 @@ struct kvec { size_t iov_len; }; +enum { + ITER_IOVEC = 0, + ITER_KVEC = 2, + ITER_BVEC = 4, +}; + struct iov_iter { int type; - const struct iovec *iov; - unsigned long nr_segs; size_t iov_offset; size_t count; + union { + const struct iovec *iov; + const struct bio_vec *bvec; + }; + unsigned long nr_segs; }; /* @@ -54,6 +63,7 @@ static inline struct iovec iov_iter_iovec(const struct iov_iter *iter) } #define iov_for_each(iov, iter, start) \ + if (!((start).type & ITER_BVEC)) \ for (iter = (start); \ (iter).count && \ ((iov = iov_iter_iovec(&(iter))), 1); \ |