path: root/include/linux/uio.h
diff options
authorLinus Torvalds <>2014-06-12 10:30:18 -0700
committerLinus Torvalds <>2014-06-12 10:30:18 -0700
commit16b9057804c02e2d351e9c8f606e909b43cbd9e7 (patch)
treea3ac6e1d9d57a8abf4267e5ead3f2de1309335eb /include/linux/uio.h
parent5c02c392cd2320e8d612376d6b72b6548a680923 (diff)
parentc2338f2dc7c1e9f6202f370c64ffd7f44f3d4b51 (diff)
Merge branch 'for-linus' of git://
Pull vfs updates from Al Viro: "This the bunch that sat in -next + lock_parent() fix. This is the minimal set; there's more pending stuff. In particular, I really hope to get acct.c fixes merged this cycle - we need that to deal sanely with delayed-mntput stuff. In the next pile, hopefully - that series is fairly short and localized (kernel/acct.c, fs/super.c and fs/namespace.c). In this pile: more iov_iter work. Most of prereqs for ->splice_write with sane locking order are there and Kent's dio rewrite would also fit nicely on top of this pile" * 'for-linus' of git:// (70 commits) lock_parent: don't step on stale ->d_parent of all-but-freed one kill generic_file_splice_write() ceph: switch to iter_file_splice_write() shmem: switch to iter_file_splice_write() nfs: switch to iter_splice_write_file() fs/splice.c: remove unneeded exports ocfs2: switch to iter_file_splice_write() ->splice_write() via ->write_iter() bio_vec-backed iov_iter optimize copy_page_{to,from}_iter() bury generic_file_aio_{read,write} lustre: get rid of messing with iovecs ceph: switch to ->write_iter() ceph_sync_direct_write: stop poking into iov_iter guts ceph_sync_read: stop poking into iov_iter guts new helper: copy_page_from_iter() fuse: switch to ->write_iter() btrfs: switch to ->write_iter() ocfs2: switch to ->write_iter() xfs: switch to ->write_iter() ...
Diffstat (limited to 'include/linux/uio.h')
1 files changed, 37 insertions, 14 deletions
diff --git a/include/linux/uio.h b/include/linux/uio.h
index 199bcc34241b..e2231e47cec1 100644
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -19,11 +19,21 @@ struct kvec {
size_t iov_len;
+enum {
+ ITER_KVEC = 2,
+ ITER_BVEC = 4,
struct iov_iter {
- const struct iovec *iov;
- unsigned long nr_segs;
+ int type;
size_t iov_offset;
size_t count;
+ union {
+ const struct iovec *iov;
+ const struct bio_vec *bvec;
+ };
+ unsigned long nr_segs;
@@ -53,6 +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); \
@@ -62,32 +73,44 @@ unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to);
size_t iov_iter_copy_from_user_atomic(struct page *page,
struct iov_iter *i, unsigned long offset, size_t bytes);
-size_t iov_iter_copy_from_user(struct page *page,
- struct iov_iter *i, unsigned long offset, size_t bytes);
void iov_iter_advance(struct iov_iter *i, size_t bytes);
int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes);
size_t iov_iter_single_seg_count(const struct iov_iter *i);
size_t copy_page_to_iter(struct page *page, size_t offset, size_t bytes,
struct iov_iter *i);
+size_t copy_page_from_iter(struct page *page, size_t offset, size_t bytes,
+ struct iov_iter *i);
+unsigned long iov_iter_alignment(const struct iov_iter *i);
+void iov_iter_init(struct iov_iter *i, int direction, const struct iovec *iov,
+ unsigned long nr_segs, size_t count);
+ssize_t iov_iter_get_pages(struct iov_iter *i, struct page **pages,
+ size_t maxsize, size_t *start);
+ssize_t iov_iter_get_pages_alloc(struct iov_iter *i, struct page ***pages,
+ size_t maxsize, size_t *start);
+int iov_iter_npages(const struct iov_iter *i, int maxpages);
-static inline void iov_iter_init(struct iov_iter *i,
- const struct iovec *iov, unsigned long nr_segs,
- size_t count, size_t written)
+static inline size_t iov_iter_count(struct iov_iter *i)
- i->iov = iov;
- i->nr_segs = nr_segs;
- i->iov_offset = 0;
- i->count = count + written;
+ return i->count;
- iov_iter_advance(i, written);
+static inline void iov_iter_truncate(struct iov_iter *i, size_t count)
+ if (i->count > count)
+ i->count = count;
-static inline size_t iov_iter_count(struct iov_iter *i)
+ * reexpand a previously truncated iterator; count must be no more than how much
+ * we had shrunk it.
+ */
+static inline void iov_iter_reexpand(struct iov_iter *i, size_t count)
- return i->count;
+ i->count = count;
int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len);
int memcpy_toiovec(struct iovec *iov, unsigned char *kdata, int len);