diff options
Diffstat (limited to 'fs/pipe.c')
-rw-r--r-- | fs/pipe.c | 254 |
1 files changed, 28 insertions, 226 deletions
diff --git a/fs/pipe.c b/fs/pipe.c index 78fd0d0788d..21981e58e2a 100644 --- a/fs/pipe.c +++ b/fs/pipe.c @@ -116,99 +116,6 @@ void pipe_wait(struct pipe_inode_info *pipe) pipe_lock(pipe); } -static int -pipe_iov_copy_from_user(void *to, struct iovec *iov, 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_from_user_inatomic(to, iov->iov_base, copy)) - return -EFAULT; - } else { - if (copy_from_user(to, iov->iov_base, copy)) - return -EFAULT; - } - to += copy; - len -= copy; - iov->iov_base += copy; - iov->iov_len -= copy; - } - 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. - */ -static void iov_fault_in_pages_read(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); - fault_in_pages_readable(iov->iov_base, this_len); - len -= this_len; - iov++; - } -} - static void anon_pipe_buf_release(struct pipe_inode_info *pipe, struct pipe_buffer *buf) { @@ -226,52 +133,6 @@ 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 +212,6 @@ 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 +220,6 @@ 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, @@ -370,17 +227,14 @@ static const struct pipe_buf_operations packet_pipe_buf_ops = { }; static ssize_t -pipe_read(struct kiocb *iocb, const struct iovec *_iov, - unsigned long nr_segs, loff_t pos) +pipe_read(struct kiocb *iocb, struct iov_iter *to) { + size_t total_len = iov_iter_count(to); struct file *filp = iocb->ki_filp; struct pipe_inode_info *pipe = filp->private_data; int do_wakeup; ssize_t ret; - struct iovec *iov = (struct iovec *)_iov; - size_t total_len; - total_len = iov_length(iov, nr_segs); /* Null read succeeds. */ if (unlikely(total_len == 0)) return 0; @@ -394,9 +248,9 @@ 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 +262,10 @@ 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, to); + if (unlikely(written < chars)) { if (!ret) - ret = error; + ret = -EFAULT; break; } ret += chars; @@ -493,24 +336,19 @@ static inline int is_packetized(struct file *file) } static ssize_t -pipe_write(struct kiocb *iocb, const struct iovec *_iov, - unsigned long nr_segs, loff_t ppos) +pipe_write(struct kiocb *iocb, struct iov_iter *from) { struct file *filp = iocb->ki_filp; struct pipe_inode_info *pipe = filp->private_data; - ssize_t ret; - int do_wakeup; - struct iovec *iov = (struct iovec *)_iov; - size_t total_len; + ssize_t ret = 0; + int do_wakeup = 0; + size_t total_len = iov_iter_count(from); ssize_t chars; - total_len = iov_length(iov, nr_segs); /* Null write succeeds. */ if (unlikely(total_len == 0)) return 0; - do_wakeup = 0; - ret = 0; __pipe_lock(pipe); if (!pipe->readers) { @@ -529,32 +367,19 @@ pipe_write(struct kiocb *iocb, const struct iovec *_iov, int offset = buf->offset + buf->len; if (ops->can_merge && offset + chars <= PAGE_SIZE) { - int error, atomic = 1; - void *addr; - - error = ops->confirm(pipe, buf); + int error = ops->confirm(pipe, buf); if (error) goto out; - iov_fault_in_pages_read(iov, chars); -redo1: - addr = ops->map(pipe, buf, atomic); - error = pipe_iov_copy_from_user(offset + addr, iov, - chars, atomic); - ops->unmap(pipe, buf, addr); - ret = error; - do_wakeup = 1; - if (error) { - if (atomic) { - atomic = 0; - goto redo1; - } + ret = copy_page_from_iter(buf->page, offset, chars, from); + if (unlikely(ret < chars)) { + error = -EFAULT; goto out; } + do_wakeup = 1; buf->len += chars; - total_len -= chars; ret = chars; - if (!total_len) + if (!iov_iter_count(from)) goto out; } } @@ -573,8 +398,7 @@ redo1: int newbuf = (pipe->curbuf + bufs) & (pipe->buffers-1); struct pipe_buffer *buf = pipe->bufs + newbuf; struct page *page = pipe->tmp_page; - char *src; - int error, atomic = 1; + int copied; if (!page) { page = alloc_page(GFP_HIGHUSER); @@ -590,40 +414,19 @@ redo1: * FIXME! Is this really true? */ do_wakeup = 1; - chars = PAGE_SIZE; - if (chars > total_len) - chars = total_len; - - iov_fault_in_pages_read(iov, chars); -redo2: - if (atomic) - src = kmap_atomic(page); - else - src = kmap(page); - - error = pipe_iov_copy_from_user(src, iov, chars, - atomic); - if (atomic) - kunmap_atomic(src); - else - kunmap(page); - - if (unlikely(error)) { - if (atomic) { - atomic = 0; - goto redo2; - } + copied = copy_page_from_iter(page, 0, PAGE_SIZE, from); + if (unlikely(copied < PAGE_SIZE && iov_iter_count(from))) { if (!ret) - ret = error; + ret = -EFAULT; break; } - ret += chars; + ret += copied; /* Insert it into the buffer array */ buf->page = page; buf->ops = &anon_pipe_buf_ops; buf->offset = 0; - buf->len = chars; + buf->len = copied; buf->flags = 0; if (is_packetized(filp)) { buf->ops = &packet_pipe_buf_ops; @@ -632,8 +435,7 @@ redo2: pipe->nrbufs = ++bufs; pipe->tmp_page = NULL; - total_len -= chars; - if (!total_len) + if (!iov_iter_count(from)) break; } if (bufs < pipe->buffers) @@ -1145,10 +947,10 @@ err: const struct file_operations pipefifo_fops = { .open = fifo_open, .llseek = no_llseek, - .read = do_sync_read, - .aio_read = pipe_read, - .write = do_sync_write, - .aio_write = pipe_write, + .read = new_sync_read, + .read_iter = pipe_read, + .write = new_sync_write, + .write_iter = pipe_write, .poll = pipe_poll, .unlocked_ioctl = pipe_ioctl, .release = pipe_release, |