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authorLinus Torvalds <torvalds@linux-foundation.org>2014-04-12 14:49:50 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-04-12 14:49:50 -0700
commit5166701b368caea89d57b14bf41cf39e819dad51 (patch)
treec73b9d4860809e3afa9359be9d03ba2d8d98a18e /include/linux/uio.h
parent0a7418f5f569512e98789c439198eed4b507cce3 (diff)
parenta786c06d9f2719203c00b3d97b21f9a96980d0b5 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro: "The first vfs pile, with deep apologies for being very late in this window. Assorted cleanups and fixes, plus a large preparatory part of iov_iter work. There's a lot more of that, but it'll probably go into the next merge window - it *does* shape up nicely, removes a lot of boilerplate, gets rid of locking inconsistencie between aio_write and splice_write and I hope to get Kent's direct-io rewrite merged into the same queue, but some of the stuff after this point is having (mostly trivial) conflicts with the things already merged into mainline and with some I want more testing. This one passes LTP and xfstests without regressions, in addition to usual beating. BTW, readahead02 in ltp syscalls testsuite has started giving failures since "mm/readahead.c: fix readahead failure for memoryless NUMA nodes and limit readahead pages" - might be a false positive, might be a real regression..." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits) missing bits of "splice: fix racy pipe->buffers uses" cifs: fix the race in cifs_writev() ceph_sync_{,direct_}write: fix an oops on ceph_osdc_new_request() failure kill generic_file_buffered_write() ocfs2_file_aio_write(): switch to generic_perform_write() ceph_aio_write(): switch to generic_perform_write() xfs_file_buffered_aio_write(): switch to generic_perform_write() export generic_perform_write(), start getting rid of generic_file_buffer_write() generic_file_direct_write(): get rid of ppos argument btrfs_file_aio_write(): get rid of ppos kill the 5th argument of generic_file_buffered_write() kill the 4th argument of __generic_file_aio_write() lustre: don't open-code kernel_recvmsg() ocfs2: don't open-code kernel_recvmsg() drbd: don't open-code kernel_recvmsg() constify blk_rq_map_user_iov() and friends lustre: switch to kernel_sendmsg() ocfs2: don't open-code kernel_sendmsg() take iov_iter stuff to mm/iov_iter.c process_vm_access: tidy up a bit ...
Diffstat (limited to 'include/linux/uio.h')
-rw-r--r--include/linux/uio.h52
1 files changed, 52 insertions, 0 deletions
diff --git a/include/linux/uio.h b/include/linux/uio.h
index c55ce243cc09..199bcc34241b 100644
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -9,14 +9,23 @@
#ifndef __LINUX_UIO_H
#define __LINUX_UIO_H
+#include <linux/kernel.h>
#include <uapi/linux/uio.h>
+struct page;
struct kvec {
void *iov_base; /* and that should *never* hold a userland pointer */
size_t iov_len;
};
+struct iov_iter {
+ const struct iovec *iov;
+ unsigned long nr_segs;
+ size_t iov_offset;
+ size_t count;
+};
+
/*
* Total number of bytes covered by an iovec.
*
@@ -34,8 +43,51 @@ static inline size_t iov_length(const struct iovec *iov, unsigned long nr_segs)
return ret;
}
+static inline struct iovec iov_iter_iovec(const struct iov_iter *iter)
+{
+ return (struct iovec) {
+ .iov_base = iter->iov->iov_base + iter->iov_offset,
+ .iov_len = min(iter->count,
+ iter->iov->iov_len - iter->iov_offset),
+ };
+}
+
+#define iov_for_each(iov, iter, start) \
+ for (iter = (start); \
+ (iter).count && \
+ ((iov = iov_iter_iovec(&(iter))), 1); \
+ iov_iter_advance(&(iter), (iov).iov_len))
+
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);
+
+static inline void iov_iter_init(struct iov_iter *i,
+ const struct iovec *iov, unsigned long nr_segs,
+ size_t count, size_t written)
+{
+ i->iov = iov;
+ i->nr_segs = nr_segs;
+ i->iov_offset = 0;
+ i->count = count + written;
+
+ iov_iter_advance(i, written);
+}
+
+static inline size_t iov_iter_count(struct iov_iter *i)
+{
+ return i->count;
+}
+
int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len);
int memcpy_toiovec(struct iovec *iov, unsigned char *kdata, int len);
+
#endif