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author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-04-12 14:49:50 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-04-12 14:49:50 -0700 |
commit | 5166701b368caea89d57b14bf41cf39e819dad51 (patch) | |
tree | c73b9d4860809e3afa9359be9d03ba2d8d98a18e /fs/pipe.c | |
parent | 0a7418f5f569512e98789c439198eed4b507cce3 (diff) | |
parent | a786c06d9f2719203c00b3d97b21f9a96980d0b5 (diff) | |
download | op-kernel-dev-5166701b368caea89d57b14bf41cf39e819dad51.zip op-kernel-dev-5166701b368caea89d57b14bf41cf39e819dad51.tar.gz |
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 'fs/pipe.c')
-rw-r--r-- | fs/pipe.c | 133 |
1 files changed, 16 insertions, 117 deletions
@@ -142,55 +142,6 @@ pipe_iov_copy_from_user(void *to, struct iovec *iov, unsigned long len, return 0; } -static int -pipe_iov_copy_to_user(struct iovec *iov, const void *from, unsigned long len, - int atomic) -{ - unsigned long copy; - - while (len > 0) { - while (!iov->iov_len) - iov++; - copy = min_t(unsigned long, len, iov->iov_len); - - if (atomic) { - if (__copy_to_user_inatomic(iov->iov_base, from, copy)) - return -EFAULT; - } else { - if (copy_to_user(iov->iov_base, from, copy)) - return -EFAULT; - } - from += copy; - len -= copy; - iov->iov_base += copy; - iov->iov_len -= copy; - } - return 0; -} - -/* - * Attempt to pre-fault in the user memory, so we can use atomic copies. - * Returns the number of bytes not faulted in. - */ -static int iov_fault_in_pages_write(struct iovec *iov, unsigned long len) -{ - while (!iov->iov_len) - iov++; - - while (len > 0) { - unsigned long this_len; - - this_len = min_t(unsigned long, len, iov->iov_len); - if (fault_in_pages_writeable(iov->iov_base, this_len)) - break; - - len -= this_len; - iov++; - } - - return len; -} - /* * Pre-fault in the user memory, so we can use atomic copies. */ @@ -226,52 +177,6 @@ static void anon_pipe_buf_release(struct pipe_inode_info *pipe, } /** - * generic_pipe_buf_map - virtually map a pipe buffer - * @pipe: the pipe that the buffer belongs to - * @buf: the buffer that should be mapped - * @atomic: whether to use an atomic map - * - * Description: - * This function returns a kernel virtual address mapping for the - * pipe_buffer passed in @buf. If @atomic is set, an atomic map is provided - * and the caller has to be careful not to fault before calling - * the unmap function. - * - * Note that this function calls kmap_atomic() if @atomic != 0. - */ -void *generic_pipe_buf_map(struct pipe_inode_info *pipe, - struct pipe_buffer *buf, int atomic) -{ - if (atomic) { - buf->flags |= PIPE_BUF_FLAG_ATOMIC; - return kmap_atomic(buf->page); - } - - return kmap(buf->page); -} -EXPORT_SYMBOL(generic_pipe_buf_map); - -/** - * generic_pipe_buf_unmap - unmap a previously mapped pipe buffer - * @pipe: the pipe that the buffer belongs to - * @buf: the buffer that should be unmapped - * @map_data: the data that the mapping function returned - * - * Description: - * This function undoes the mapping that ->map() provided. - */ -void generic_pipe_buf_unmap(struct pipe_inode_info *pipe, - struct pipe_buffer *buf, void *map_data) -{ - if (buf->flags & PIPE_BUF_FLAG_ATOMIC) { - buf->flags &= ~PIPE_BUF_FLAG_ATOMIC; - kunmap_atomic(map_data); - } else - kunmap(buf->page); -} -EXPORT_SYMBOL(generic_pipe_buf_unmap); - -/** * generic_pipe_buf_steal - attempt to take ownership of a &pipe_buffer * @pipe: the pipe that the buffer belongs to * @buf: the buffer to attempt to steal @@ -351,8 +256,6 @@ EXPORT_SYMBOL(generic_pipe_buf_release); static const struct pipe_buf_operations anon_pipe_buf_ops = { .can_merge = 1, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, .confirm = generic_pipe_buf_confirm, .release = anon_pipe_buf_release, .steal = generic_pipe_buf_steal, @@ -361,8 +264,6 @@ static const struct pipe_buf_operations anon_pipe_buf_ops = { static const struct pipe_buf_operations packet_pipe_buf_ops = { .can_merge = 0, - .map = generic_pipe_buf_map, - .unmap = generic_pipe_buf_unmap, .confirm = generic_pipe_buf_confirm, .release = anon_pipe_buf_release, .steal = generic_pipe_buf_steal, @@ -379,12 +280,15 @@ pipe_read(struct kiocb *iocb, const struct iovec *_iov, ssize_t ret; struct iovec *iov = (struct iovec *)_iov; size_t total_len; + struct iov_iter iter; total_len = iov_length(iov, nr_segs); /* Null read succeeds. */ if (unlikely(total_len == 0)) return 0; + iov_iter_init(&iter, iov, nr_segs, total_len, 0); + do_wakeup = 0; ret = 0; __pipe_lock(pipe); @@ -394,9 +298,9 @@ pipe_read(struct kiocb *iocb, const struct iovec *_iov, int curbuf = pipe->curbuf; struct pipe_buffer *buf = pipe->bufs + curbuf; const struct pipe_buf_operations *ops = buf->ops; - void *addr; size_t chars = buf->len; - int error, atomic; + size_t written; + int error; if (chars > total_len) chars = total_len; @@ -408,21 +312,10 @@ pipe_read(struct kiocb *iocb, const struct iovec *_iov, break; } - atomic = !iov_fault_in_pages_write(iov, chars); -redo: - addr = ops->map(pipe, buf, atomic); - error = pipe_iov_copy_to_user(iov, addr + buf->offset, chars, atomic); - ops->unmap(pipe, buf, addr); - if (unlikely(error)) { - /* - * Just retry with the slow path if we failed. - */ - if (atomic) { - atomic = 0; - goto redo; - } + written = copy_page_to_iter(buf->page, buf->offset, chars, &iter); + if (unlikely(written < chars)) { if (!ret) - ret = error; + ret = -EFAULT; break; } ret += chars; @@ -538,10 +431,16 @@ pipe_write(struct kiocb *iocb, const struct iovec *_iov, iov_fault_in_pages_read(iov, chars); redo1: - addr = ops->map(pipe, buf, atomic); + if (atomic) + addr = kmap_atomic(buf->page); + else + addr = kmap(buf->page); error = pipe_iov_copy_from_user(offset + addr, iov, chars, atomic); - ops->unmap(pipe, buf, addr); + if (atomic) + kunmap_atomic(addr); + else + kunmap(buf->page); ret = error; do_wakeup = 1; if (error) { |