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fs/splice.c
39.6 KB
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/* * "splice": joining two ropes together by interweaving their strands. * * This is the "extended pipe" functionality, where a pipe is used as * an arbitrary in-memory buffer. Think of a pipe as a small kernel * buffer that you can use to transfer data from one end to the other. * * The traditional unix read/write is extended with a "splice()" operation * that transfers data buffers to or from a pipe buffer. * * Named by Larry McVoy, original implementation from Linus, extended by |
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* Jens to support splicing to files, network, direct splicing, etc and * fixing lots of bugs. |
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* |
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* Copyright (C) 2005-2006 Jens Axboe <axboe@kernel.dk> |
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* Copyright (C) 2005-2006 Linus Torvalds <torvalds@osdl.org> * Copyright (C) 2006 Ingo Molnar <mingo@elte.hu> |
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* */ |
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#include <linux/bvec.h> |
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#include <linux/fs.h> #include <linux/file.h> #include <linux/pagemap.h> |
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#include <linux/splice.h> |
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#include <linux/memcontrol.h> |
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#include <linux/mm_inline.h> |
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#include <linux/swap.h> |
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#include <linux/writeback.h> |
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#include <linux/export.h> |
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#include <linux/syscalls.h> |
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#include <linux/uio.h> |
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#include <linux/security.h> |
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#include <linux/gfp.h> |
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#include <linux/socket.h> |
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#include <linux/compat.h> |
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#include <linux/sched/signal.h> |
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#include "internal.h" |
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|
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/* * Attempt to steal a page from a pipe buffer. This should perhaps go into * a vm helper function, it's already simplified quite a bit by the * addition of remove_mapping(). If success is returned, the caller may * attempt to reuse this page for another destination. */ |
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static int page_cache_pipe_buf_steal(struct pipe_inode_info *pipe, |
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struct pipe_buffer *buf) { struct page *page = buf->page; |
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struct address_space *mapping; |
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|
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lock_page(page); |
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mapping = page_mapping(page); if (mapping) { WARN_ON(!PageUptodate(page)); |
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|
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/* * At least for ext2 with nobh option, we need to wait on * writeback completing on this page, since we'll remove it * from the pagecache. Otherwise truncate wont wait on the * page, allowing the disk blocks to be reused by someone else * before we actually wrote our data to them. fs corruption * ensues. */ wait_on_page_writeback(page); |
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|
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if (page_has_private(page) && !try_to_release_page(page, GFP_KERNEL)) |
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goto out_unlock; |
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|
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/* * If we succeeded in removing the mapping, set LRU flag * and return good. */ if (remove_mapping(mapping, page)) { buf->flags |= PIPE_BUF_FLAG_LRU; return 0; } |
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} |
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|
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/* * Raced with truncate or failed to remove page from current * address space, unlock and return failure. */ |
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out_unlock: |
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unlock_page(page); return 1; |
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} |
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static void page_cache_pipe_buf_release(struct pipe_inode_info *pipe, |
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struct pipe_buffer *buf) { |
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put_page(buf->page); |
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buf->flags &= ~PIPE_BUF_FLAG_LRU; |
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} |
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/* * Check whether the contents of buf is OK to access. Since the content * is a page cache page, IO may be in flight. */ |
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static int page_cache_pipe_buf_confirm(struct pipe_inode_info *pipe, struct pipe_buffer *buf) |
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{ struct page *page = buf->page; |
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int err; |
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if (!PageUptodate(page)) { |
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lock_page(page); /* * Page got truncated/unhashed. This will cause a 0-byte |
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* splice, if this is the first page. |
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*/ if (!page->mapping) { err = -ENODATA; goto error; } |
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|
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/* |
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* Uh oh, read-error from disk. |
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*/ if (!PageUptodate(page)) { err = -EIO; goto error; } /* |
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* Page is ok afterall, we are done. |
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*/ |
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unlock_page(page); |
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} |
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return 0; |
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error: unlock_page(page); |
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return err; |
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} |
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const struct pipe_buf_operations page_cache_pipe_buf_ops = { |
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.can_merge = 0, |
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.confirm = page_cache_pipe_buf_confirm, |
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.release = page_cache_pipe_buf_release, |
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.steal = page_cache_pipe_buf_steal, |
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.get = generic_pipe_buf_get, |
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}; |
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static int user_page_pipe_buf_steal(struct pipe_inode_info *pipe, struct pipe_buffer *buf) { |
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if (!(buf->flags & PIPE_BUF_FLAG_GIFT)) return 1; |
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buf->flags |= PIPE_BUF_FLAG_LRU; |
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return generic_pipe_buf_steal(pipe, buf); |
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} |
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static const struct pipe_buf_operations user_page_pipe_buf_ops = { |
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.can_merge = 0, |
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.confirm = generic_pipe_buf_confirm, |
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.release = page_cache_pipe_buf_release, .steal = user_page_pipe_buf_steal, |
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.get = generic_pipe_buf_get, |
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}; |
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static void wakeup_pipe_readers(struct pipe_inode_info *pipe) { smp_mb(); if (waitqueue_active(&pipe->wait)) wake_up_interruptible(&pipe->wait); kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN); } |
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/** * splice_to_pipe - fill passed data into a pipe * @pipe: pipe to fill * @spd: data to fill * * Description: |
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* @spd contains a map of pages and len/offset tuples, along with |
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* the struct pipe_buf_operations associated with these pages. This * function will link that data to the pipe. * |
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*/ |
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ssize_t splice_to_pipe(struct pipe_inode_info *pipe, struct splice_pipe_desc *spd) |
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{ |
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unsigned int spd_pages = spd->nr_pages; |
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int ret = 0, page_nr = 0; |
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|
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if (!spd_pages) return 0; |
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if (unlikely(!pipe->readers)) { send_sig(SIGPIPE, current, 0); ret = -EPIPE; goto out; } |
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|
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while (pipe->nrbufs < pipe->buffers) { int newbuf = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1); struct pipe_buffer *buf = pipe->bufs + newbuf; |
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|
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buf->page = spd->pages[page_nr]; buf->offset = spd->partial[page_nr].offset; buf->len = spd->partial[page_nr].len; buf->private = spd->partial[page_nr].private; buf->ops = spd->ops; |
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buf->flags = 0; |
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|
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pipe->nrbufs++; page_nr++; ret += buf->len; |
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|
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if (!--spd->nr_pages) |
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break; |
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} |
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if (!ret) ret = -EAGAIN; |
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|
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out: |
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while (page_nr < spd_pages) |
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spd->spd_release(spd, page_nr++); |
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return ret; } |
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EXPORT_SYMBOL_GPL(splice_to_pipe); |
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|
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ssize_t add_to_pipe(struct pipe_inode_info *pipe, struct pipe_buffer *buf) { int ret; if (unlikely(!pipe->readers)) { send_sig(SIGPIPE, current, 0); ret = -EPIPE; } else if (pipe->nrbufs == pipe->buffers) { ret = -EAGAIN; } else { int newbuf = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1); pipe->bufs[newbuf] = *buf; pipe->nrbufs++; return buf->len; } |
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pipe_buf_release(pipe, buf); |
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return ret; } EXPORT_SYMBOL(add_to_pipe); |
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/* * Check if we need to grow the arrays holding pages and partial page * descriptions. */ |
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int splice_grow_spd(const struct pipe_inode_info *pipe, struct splice_pipe_desc *spd) |
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{ |
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unsigned int buffers = READ_ONCE(pipe->buffers); |
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spd->nr_pages_max = buffers; if (buffers <= PIPE_DEF_BUFFERS) |
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return 0; |
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spd->pages = kmalloc_array(buffers, sizeof(struct page *), GFP_KERNEL); spd->partial = kmalloc_array(buffers, sizeof(struct partial_page), GFP_KERNEL); |
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if (spd->pages && spd->partial) return 0; kfree(spd->pages); kfree(spd->partial); return -ENOMEM; } |
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void splice_shrink_spd(struct splice_pipe_desc *spd) |
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{ |
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if (spd->nr_pages_max <= PIPE_DEF_BUFFERS) |
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return; kfree(spd->pages); kfree(spd->partial); } |
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/** * generic_file_splice_read - splice data from file to a pipe * @in: file to splice from |
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* @ppos: position in @in |
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* @pipe: pipe to splice to * @len: number of bytes to splice * @flags: splice modifier flags * |
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* Description: * Will read pages from given file and fill them into a pipe. Can be |
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* used as long as it has more or less sane ->read_iter(). |
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* |
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*/ |
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ssize_t generic_file_splice_read(struct file *in, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags) |
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{ |
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struct iov_iter to; struct kiocb kiocb; |
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int idx, ret; |
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|
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iov_iter_pipe(&to, ITER_PIPE | READ, pipe, len); idx = to.idx; init_sync_kiocb(&kiocb, in); kiocb.ki_pos = *ppos; |
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ret = call_read_iter(in, &kiocb, &to); |
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if (ret > 0) { |
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*ppos = kiocb.ki_pos; |
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file_accessed(in); |
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} else if (ret < 0) { |
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to.idx = idx; to.iov_offset = 0; iov_iter_advance(&to, 0); /* to free what was emitted */ |
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/* * callers of ->splice_read() expect -EAGAIN on * "can't put anything in there", rather than -EFAULT. */ if (ret == -EFAULT) ret = -EAGAIN; |
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} |
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return ret; } |
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EXPORT_SYMBOL(generic_file_splice_read); |
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const struct pipe_buf_operations default_pipe_buf_ops = { |
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.can_merge = 0, |
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.confirm = generic_pipe_buf_confirm, .release = generic_pipe_buf_release, .steal = generic_pipe_buf_steal, .get = generic_pipe_buf_get, }; |
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static int generic_pipe_buf_nosteal(struct pipe_inode_info *pipe, struct pipe_buffer *buf) { return 1; } /* Pipe buffer operations for a socket and similar. */ const struct pipe_buf_operations nosteal_pipe_buf_ops = { .can_merge = 0, |
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.confirm = generic_pipe_buf_confirm, .release = generic_pipe_buf_release, .steal = generic_pipe_buf_nosteal, .get = generic_pipe_buf_get, }; EXPORT_SYMBOL(nosteal_pipe_buf_ops); |
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static ssize_t kernel_readv(struct file *file, const struct kvec *vec, |
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unsigned long vlen, loff_t offset) { mm_segment_t old_fs; loff_t pos = offset; ssize_t res; old_fs = get_fs(); set_fs(get_ds()); /* The cast to a user pointer is valid due to the set_fs() */ |
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res = vfs_readv(file, (const struct iovec __user *)vec, vlen, &pos, 0); |
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set_fs(old_fs); return res; } |
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static ssize_t default_file_splice_read(struct file *in, loff_t *ppos, |
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struct pipe_inode_info *pipe, size_t len, unsigned int flags) { |
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struct kvec *vec, __vec[PIPE_DEF_BUFFERS]; struct iov_iter to; struct page **pages; |
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unsigned int nr_pages; |
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size_t offset, base, copied = 0; |
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ssize_t res; |
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int i; |
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|
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if (pipe->nrbufs == pipe->buffers) return -EAGAIN; |
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|
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/* * Try to keep page boundaries matching to source pagecache ones - * it probably won't be much help, but... */ |
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offset = *ppos & ~PAGE_MASK; |
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|
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iov_iter_pipe(&to, ITER_PIPE | READ, pipe, len + offset); |
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|
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res = iov_iter_get_pages_alloc(&to, &pages, len + offset, &base); |
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if (res <= 0) return -ENOMEM; |
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|
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nr_pages = DIV_ROUND_UP(res + base, PAGE_SIZE); |
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|
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vec = __vec; if (nr_pages > PIPE_DEF_BUFFERS) { |
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vec = kmalloc_array(nr_pages, sizeof(struct kvec), GFP_KERNEL); |
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if (unlikely(!vec)) { res = -ENOMEM; goto out; } |
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} |
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|
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pipe->bufs[to.idx].offset = offset; pipe->bufs[to.idx].len -= offset; for (i = 0; i < nr_pages; i++) { size_t this_len = min_t(size_t, len, PAGE_SIZE - offset); vec[i].iov_base = page_address(pages[i]) + offset; vec[i].iov_len = this_len; len -= this_len; offset = 0; |
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} |
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|
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res = kernel_readv(in, vec, nr_pages, *ppos); if (res > 0) { copied = res; |
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*ppos += res; |
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} |
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|
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if (vec != __vec) kfree(vec); |
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out: for (i = 0; i < nr_pages; i++) put_page(pages[i]); kvfree(pages); iov_iter_advance(&to, copied); /* truncates and discards */ |
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return res; |
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} |
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|
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/* |
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* Send 'sd->len' bytes to socket from 'sd->file' at position 'sd->pos' |
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* using sendpage(). Return the number of bytes sent. |
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*/ |
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static int pipe_to_sendpage(struct pipe_inode_info *pipe, |
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struct pipe_buffer *buf, struct splice_desc *sd) { |
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struct file *file = sd->u.file; |
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loff_t pos = sd->pos; |
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int more; |
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|
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423 |
if (!likely(file->f_op->sendpage)) |
a8adbe378 fs/splice: Pull b... |
424 |
return -EINVAL; |
35f9c09fe tcp: tcp_sendpage... |
425 |
more = (sd->flags & SPLICE_F_MORE) ? MSG_MORE : 0; |
ae62ca7b0 tcp: fix MSG_SEND... |
426 427 |
if (sd->len < sd->total_len && pipe->nrbufs > 1) |
35f9c09fe tcp: tcp_sendpage... |
428 |
more |= MSG_SENDPAGE_NOTLAST; |
ae62ca7b0 tcp: fix MSG_SEND... |
429 |
|
a8adbe378 fs/splice: Pull b... |
430 431 |
return file->f_op->sendpage(file, buf->page, buf->offset, sd->len, &pos, more); |
5274f052e [PATCH] Introduce... |
432 |
} |
b3c2d2ddd splice: split up ... |
433 434 435 436 437 438 439 |
static void wakeup_pipe_writers(struct pipe_inode_info *pipe) { smp_mb(); if (waitqueue_active(&pipe->wait)) wake_up_interruptible(&pipe->wait); kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT); } |
932cc6d4f splice: completel... |
440 |
/** |
b3c2d2ddd splice: split up ... |
441 |
* splice_from_pipe_feed - feed available data from a pipe to a file |
932cc6d4f splice: completel... |
442 443 444 445 446 |
* @pipe: pipe to splice from * @sd: information to @actor * @actor: handler that splices the data * * Description: |
b3c2d2ddd splice: split up ... |
447 448 449 450 451 452 453 |
* This function loops over the pipe and calls @actor to do the * actual moving of a single struct pipe_buffer to the desired * destination. It returns when there's no more buffers left in * the pipe or if the requested number of bytes (@sd->total_len) * have been copied. It returns a positive number (one) if the * pipe needs to be filled with more data, zero if the required * number of bytes have been copied and -errno on error. |
932cc6d4f splice: completel... |
454 |
* |
b3c2d2ddd splice: split up ... |
455 456 457 458 |
* This, together with splice_from_pipe_{begin,end,next}, may be * used to implement the functionality of __splice_from_pipe() when * locking is required around copying the pipe buffers to the * destination. |
83f9135bd [PATCH] splice: a... |
459 |
*/ |
96f9bc8fb fs/splice.c: remo... |
460 |
static int splice_from_pipe_feed(struct pipe_inode_info *pipe, struct splice_desc *sd, |
b3c2d2ddd splice: split up ... |
461 |
splice_actor *actor) |
5274f052e [PATCH] Introduce... |
462 |
{ |
b3c2d2ddd splice: split up ... |
463 |
int ret; |
5274f052e [PATCH] Introduce... |
464 |
|
b3c2d2ddd splice: split up ... |
465 466 |
while (pipe->nrbufs) { struct pipe_buffer *buf = pipe->bufs + pipe->curbuf; |
5274f052e [PATCH] Introduce... |
467 |
|
b3c2d2ddd splice: split up ... |
468 469 470 |
sd->len = buf->len; if (sd->len > sd->total_len) sd->len = sd->total_len; |
5274f052e [PATCH] Introduce... |
471 |
|
fba597db4 pipe: add pipe_bu... |
472 |
ret = pipe_buf_confirm(pipe, buf); |
a8adbe378 fs/splice: Pull b... |
473 |
if (unlikely(ret)) { |
b3c2d2ddd splice: split up ... |
474 475 476 477 |
if (ret == -ENODATA) ret = 0; return ret; } |
a8adbe378 fs/splice: Pull b... |
478 479 480 481 |
ret = actor(pipe, buf, sd); if (ret <= 0) return ret; |
b3c2d2ddd splice: split up ... |
482 483 484 485 486 487 488 489 490 |
buf->offset += ret; buf->len -= ret; sd->num_spliced += ret; sd->len -= ret; sd->pos += ret; sd->total_len -= ret; if (!buf->len) { |
a779638cf pipe: add pipe_bu... |
491 |
pipe_buf_release(pipe, buf); |
35f3d14db pipe: add support... |
492 |
pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1); |
b3c2d2ddd splice: split up ... |
493 |
pipe->nrbufs--; |
6447a3cf1 get rid of pipe->... |
494 |
if (pipe->files) |
b3c2d2ddd splice: split up ... |
495 496 |
sd->need_wakeup = true; } |
5274f052e [PATCH] Introduce... |
497 |
|
b3c2d2ddd splice: split up ... |
498 499 500 |
if (!sd->total_len) return 0; } |
5274f052e [PATCH] Introduce... |
501 |
|
b3c2d2ddd splice: split up ... |
502 503 |
return 1; } |
5274f052e [PATCH] Introduce... |
504 |
|
b3c2d2ddd splice: split up ... |
505 506 507 508 509 510 511 512 513 514 |
/** * splice_from_pipe_next - wait for some data to splice from * @pipe: pipe to splice from * @sd: information about the splice operation * * Description: * This function will wait for some data and return a positive * value (one) if pipe buffers are available. It will return zero * or -errno if no more data needs to be spliced. */ |
96f9bc8fb fs/splice.c: remo... |
515 |
static int splice_from_pipe_next(struct pipe_inode_info *pipe, struct splice_desc *sd) |
b3c2d2ddd splice: split up ... |
516 |
{ |
c725bfce7 vfs: Make sendfil... |
517 518 519 520 521 522 |
/* * Check for signal early to make process killable when there are * always buffers available */ if (signal_pending(current)) return -ERESTARTSYS; |
b3c2d2ddd splice: split up ... |
523 524 525 |
while (!pipe->nrbufs) { if (!pipe->writers) return 0; |
016b661e2 [PATCH] splice: f... |
526 |
|
b3c2d2ddd splice: split up ... |
527 528 |
if (!pipe->waiting_writers && sd->num_spliced) return 0; |
73d62d83e [PATCH] splice: c... |
529 |
|
b3c2d2ddd splice: split up ... |
530 531 |
if (sd->flags & SPLICE_F_NONBLOCK) return -EAGAIN; |
5274f052e [PATCH] Introduce... |
532 |
|
b3c2d2ddd splice: split up ... |
533 534 |
if (signal_pending(current)) return -ERESTARTSYS; |
5274f052e [PATCH] Introduce... |
535 |
|
b3c2d2ddd splice: split up ... |
536 537 538 |
if (sd->need_wakeup) { wakeup_pipe_writers(pipe); sd->need_wakeup = false; |
5274f052e [PATCH] Introduce... |
539 |
} |
b3c2d2ddd splice: split up ... |
540 541 |
pipe_wait(pipe); } |
29e350944 splice: add SPLIC... |
542 |
|
b3c2d2ddd splice: split up ... |
543 544 |
return 1; } |
5274f052e [PATCH] Introduce... |
545 |
|
b3c2d2ddd splice: split up ... |
546 547 |
/** * splice_from_pipe_begin - start splicing from pipe |
b80901bbf splice: fix new k... |
548 |
* @sd: information about the splice operation |
b3c2d2ddd splice: split up ... |
549 550 551 552 553 554 |
* * Description: * This function should be called before a loop containing * splice_from_pipe_next() and splice_from_pipe_feed() to * initialize the necessary fields of @sd. */ |
96f9bc8fb fs/splice.c: remo... |
555 |
static void splice_from_pipe_begin(struct splice_desc *sd) |
b3c2d2ddd splice: split up ... |
556 557 558 559 |
{ sd->num_spliced = 0; sd->need_wakeup = false; } |
5274f052e [PATCH] Introduce... |
560 |
|
b3c2d2ddd splice: split up ... |
561 562 563 564 565 566 567 568 569 570 |
/** * splice_from_pipe_end - finish splicing from pipe * @pipe: pipe to splice from * @sd: information about the splice operation * * Description: * This function will wake up pipe writers if necessary. It should * be called after a loop containing splice_from_pipe_next() and * splice_from_pipe_feed(). */ |
96f9bc8fb fs/splice.c: remo... |
571 |
static void splice_from_pipe_end(struct pipe_inode_info *pipe, struct splice_desc *sd) |
b3c2d2ddd splice: split up ... |
572 573 574 575 |
{ if (sd->need_wakeup) wakeup_pipe_writers(pipe); } |
5274f052e [PATCH] Introduce... |
576 |
|
b3c2d2ddd splice: split up ... |
577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 |
/** * __splice_from_pipe - splice data from a pipe to given actor * @pipe: pipe to splice from * @sd: information to @actor * @actor: handler that splices the data * * Description: * This function does little more than loop over the pipe and call * @actor to do the actual moving of a single struct pipe_buffer to * the desired destination. See pipe_to_file, pipe_to_sendpage, or * pipe_to_user. * */ ssize_t __splice_from_pipe(struct pipe_inode_info *pipe, struct splice_desc *sd, splice_actor *actor) { int ret; |
5274f052e [PATCH] Introduce... |
594 |
|
b3c2d2ddd splice: split up ... |
595 596 |
splice_from_pipe_begin(sd); do { |
c2489e07c vfs: Avoid softlo... |
597 |
cond_resched(); |
b3c2d2ddd splice: split up ... |
598 599 600 601 602 603 604 |
ret = splice_from_pipe_next(pipe, sd); if (ret > 0) ret = splice_from_pipe_feed(pipe, sd, actor); } while (ret > 0); splice_from_pipe_end(pipe, sd); return sd->num_spliced ? sd->num_spliced : ret; |
5274f052e [PATCH] Introduce... |
605 |
} |
40bee44ea Export __splice_f... |
606 |
EXPORT_SYMBOL(__splice_from_pipe); |
5274f052e [PATCH] Introduce... |
607 |
|
932cc6d4f splice: completel... |
608 609 610 611 612 613 614 615 616 617 |
/** * splice_from_pipe - splice data from a pipe to a file * @pipe: pipe to splice from * @out: file to splice to * @ppos: position in @out * @len: how many bytes to splice * @flags: splice modifier flags * @actor: handler that splices the data * * Description: |
2933970b9 splice: remove i_... |
618 |
* See __splice_from_pipe. This function locks the pipe inode, |
932cc6d4f splice: completel... |
619 620 621 |
* otherwise it's identical to __splice_from_pipe(). * */ |
6da618098 [PATCH] Introduce... |
622 623 624 625 626 |
ssize_t splice_from_pipe(struct pipe_inode_info *pipe, struct file *out, loff_t *ppos, size_t len, unsigned int flags, splice_actor *actor) { ssize_t ret; |
c66ab6fa7 splice: abstract ... |
627 628 629 630 |
struct splice_desc sd = { .total_len = len, .flags = flags, .pos = *ppos, |
6a14b90bb vmsplice: add vms... |
631 |
.u.file = out, |
c66ab6fa7 splice: abstract ... |
632 |
}; |
6da618098 [PATCH] Introduce... |
633 |
|
61e0d47c3 splice: add helpe... |
634 |
pipe_lock(pipe); |
c66ab6fa7 splice: abstract ... |
635 |
ret = __splice_from_pipe(pipe, &sd, actor); |
61e0d47c3 splice: add helpe... |
636 |
pipe_unlock(pipe); |
6da618098 [PATCH] Introduce... |
637 638 639 640 641 |
return ret; } /** |
8d0207652 ->splice_write() ... |
642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 |
* iter_file_splice_write - splice data from a pipe to a file * @pipe: pipe info * @out: file to write to * @ppos: position in @out * @len: number of bytes to splice * @flags: splice modifier flags * * Description: * Will either move or copy pages (determined by @flags options) from * the given pipe inode to the given file. * This one is ->write_iter-based. * */ ssize_t iter_file_splice_write(struct pipe_inode_info *pipe, struct file *out, loff_t *ppos, size_t len, unsigned int flags) { struct splice_desc sd = { .total_len = len, .flags = flags, .pos = *ppos, .u.file = out, }; int nbufs = pipe->buffers; struct bio_vec *array = kcalloc(nbufs, sizeof(struct bio_vec), GFP_KERNEL); ssize_t ret; if (unlikely(!array)) return -ENOMEM; pipe_lock(pipe); splice_from_pipe_begin(&sd); while (sd.total_len) { struct iov_iter from; |
8d0207652 ->splice_write() ... |
678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 |
size_t left; int n, idx; ret = splice_from_pipe_next(pipe, &sd); if (ret <= 0) break; if (unlikely(nbufs < pipe->buffers)) { kfree(array); nbufs = pipe->buffers; array = kcalloc(nbufs, sizeof(struct bio_vec), GFP_KERNEL); if (!array) { ret = -ENOMEM; break; } } /* build the vector */ left = sd.total_len; for (n = 0, idx = pipe->curbuf; left && n < pipe->nrbufs; n++, idx++) { struct pipe_buffer *buf = pipe->bufs + idx; size_t this_len = buf->len; if (this_len > left) this_len = left; if (idx == pipe->buffers - 1) idx = -1; |
fba597db4 pipe: add pipe_bu... |
707 |
ret = pipe_buf_confirm(pipe, buf); |
8d0207652 ->splice_write() ... |
708 709 710 711 712 713 714 715 716 717 718 |
if (unlikely(ret)) { if (ret == -ENODATA) ret = 0; goto done; } array[n].bv_page = buf->page; array[n].bv_len = this_len; array[n].bv_offset = buf->offset; left -= this_len; } |
05afcb77e new helper: iov_i... |
719 720 |
iov_iter_bvec(&from, ITER_BVEC | WRITE, array, n, sd.total_len - left); |
abbb65899 fs: implement vfs... |
721 |
ret = vfs_iter_write(out, &from, &sd.pos, 0); |
8d0207652 ->splice_write() ... |
722 723 724 725 726 |
if (ret <= 0) break; sd.num_spliced += ret; sd.total_len -= ret; |
dbe4e192a fs: add vfs_iter_... |
727 |
*ppos = sd.pos; |
8d0207652 ->splice_write() ... |
728 729 730 731 732 |
/* dismiss the fully eaten buffers, adjust the partial one */ while (ret) { struct pipe_buffer *buf = pipe->bufs + pipe->curbuf; if (ret >= buf->len) { |
8d0207652 ->splice_write() ... |
733 734 |
ret -= buf->len; buf->len = 0; |
a779638cf pipe: add pipe_bu... |
735 |
pipe_buf_release(pipe, buf); |
8d0207652 ->splice_write() ... |
736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 |
pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1); pipe->nrbufs--; if (pipe->files) sd.need_wakeup = true; } else { buf->offset += ret; buf->len -= ret; ret = 0; } } } done: kfree(array); splice_from_pipe_end(pipe, &sd); pipe_unlock(pipe); if (sd.num_spliced) ret = sd.num_spliced; return ret; } EXPORT_SYMBOL(iter_file_splice_write); |
b2858d7d1 splice: fix kmaps... |
760 761 |
static int write_pipe_buf(struct pipe_inode_info *pipe, struct pipe_buffer *buf, struct splice_desc *sd) |
0b0a47f5c splice: implement... |
762 |
{ |
b2858d7d1 splice: fix kmaps... |
763 764 |
int ret; void *data; |
06ae43f34 Don't bother with... |
765 |
loff_t tmp = sd->pos; |
b2858d7d1 splice: fix kmaps... |
766 |
|
fbb32750a pipe: kill ->map(... |
767 |
data = kmap(buf->page); |
06ae43f34 Don't bother with... |
768 |
ret = __kernel_write(sd->u.file, data + buf->offset, sd->len, &tmp); |
fbb32750a pipe: kill ->map(... |
769 |
kunmap(buf->page); |
b2858d7d1 splice: fix kmaps... |
770 771 |
return ret; |
0b0a47f5c splice: implement... |
772 773 774 775 776 777 |
} static ssize_t default_file_splice_write(struct pipe_inode_info *pipe, struct file *out, loff_t *ppos, size_t len, unsigned int flags) { |
b2858d7d1 splice: fix kmaps... |
778 |
ssize_t ret; |
0b0a47f5c splice: implement... |
779 |
|
b2858d7d1 splice: fix kmaps... |
780 781 782 |
ret = splice_from_pipe(pipe, out, ppos, len, flags, write_pipe_buf); if (ret > 0) *ppos += ret; |
0b0a47f5c splice: implement... |
783 |
|
b2858d7d1 splice: fix kmaps... |
784 |
return ret; |
0b0a47f5c splice: implement... |
785 |
} |
83f9135bd [PATCH] splice: a... |
786 787 |
/** * generic_splice_sendpage - splice data from a pipe to a socket |
932cc6d4f splice: completel... |
788 |
* @pipe: pipe to splice from |
83f9135bd [PATCH] splice: a... |
789 |
* @out: socket to write to |
932cc6d4f splice: completel... |
790 |
* @ppos: position in @out |
83f9135bd [PATCH] splice: a... |
791 792 793 |
* @len: number of bytes to splice * @flags: splice modifier flags * |
932cc6d4f splice: completel... |
794 795 796 |
* Description: * Will send @len bytes from the pipe to a network socket. No data copying * is involved. |
83f9135bd [PATCH] splice: a... |
797 798 |
* */ |
3a326a2ce [PATCH] introduce... |
799 |
ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe, struct file *out, |
cbb7e577e [PATCH] splice: p... |
800 |
loff_t *ppos, size_t len, unsigned int flags) |
5274f052e [PATCH] Introduce... |
801 |
{ |
00522fb41 [PATCH] splice: r... |
802 |
return splice_from_pipe(pipe, out, ppos, len, flags, pipe_to_sendpage); |
5274f052e [PATCH] Introduce... |
803 |
} |
059a8f373 [PATCH] splice: e... |
804 |
EXPORT_SYMBOL(generic_splice_sendpage); |
a0f067802 [PATCH] splice ex... |
805 |
|
83f9135bd [PATCH] splice: a... |
806 807 808 |
/* * Attempt to initiate a splice from pipe to file. */ |
3a326a2ce [PATCH] introduce... |
809 |
static long do_splice_from(struct pipe_inode_info *pipe, struct file *out, |
cbb7e577e [PATCH] splice: p... |
810 |
loff_t *ppos, size_t len, unsigned int flags) |
5274f052e [PATCH] Introduce... |
811 |
{ |
0b0a47f5c splice: implement... |
812 813 |
ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int); |
5274f052e [PATCH] Introduce... |
814 |
|
72c2d5319 file->f_op is nev... |
815 |
if (out->f_op->splice_write) |
cc56f7de7 sendfile(): check... |
816 817 |
splice_write = out->f_op->splice_write; else |
0b0a47f5c splice: implement... |
818 |
splice_write = default_file_splice_write; |
500368f7f lift file_*_write... |
819 |
return splice_write(pipe, out, ppos, len, flags); |
5274f052e [PATCH] Introduce... |
820 |
} |
83f9135bd [PATCH] splice: a... |
821 822 823 |
/* * Attempt to initiate a splice from a file to a pipe. */ |
cbb7e577e [PATCH] splice: p... |
824 825 826 |
static long do_splice_to(struct file *in, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags) |
5274f052e [PATCH] Introduce... |
827 |
{ |
6818173bd splice: implement... |
828 829 |
ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int); |
5274f052e [PATCH] Introduce... |
830 |
int ret; |
49570e9b2 [PATCH] splice: u... |
831 |
if (unlikely(!(in->f_mode & FMODE_READ))) |
5274f052e [PATCH] Introduce... |
832 |
return -EBADF; |
cbb7e577e [PATCH] splice: p... |
833 |
ret = rw_verify_area(READ, in, ppos, len); |
5274f052e [PATCH] Introduce... |
834 835 |
if (unlikely(ret < 0)) return ret; |
03cc0789a do_splice_to(): c... |
836 837 |
if (unlikely(len > MAX_RW_COUNT)) len = MAX_RW_COUNT; |
72c2d5319 file->f_op is nev... |
838 |
if (in->f_op->splice_read) |
cc56f7de7 sendfile(): check... |
839 840 |
splice_read = in->f_op->splice_read; else |
6818173bd splice: implement... |
841 842 843 |
splice_read = default_file_splice_read; return splice_read(in, ppos, pipe, len, flags); |
5274f052e [PATCH] Introduce... |
844 |
} |
932cc6d4f splice: completel... |
845 846 847 848 849 850 851 852 853 |
/** * splice_direct_to_actor - splices data directly between two non-pipes * @in: file to splice from * @sd: actor information on where to splice to * @actor: handles the data splicing * * Description: * This is a special case helper to splice directly between two * points, without requiring an explicit pipe. Internally an allocated |
79685b8de docbook: add pipe... |
854 |
* pipe is cached in the process, and reused during the lifetime of |
932cc6d4f splice: completel... |
855 856 |
* that process. * |
c66ab6fa7 splice: abstract ... |
857 858 859 |
*/ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd, splice_direct_actor *actor) |
b92ce5589 [PATCH] splice: a... |
860 861 862 863 |
{ struct pipe_inode_info *pipe; long ret, bytes; umode_t i_mode; |
c66ab6fa7 splice: abstract ... |
864 |
size_t len; |
0ff28d9f4 splice: sendfile(... |
865 |
int i, flags, more; |
b92ce5589 [PATCH] splice: a... |
866 867 868 869 870 871 |
/* * We require the input being a regular file, as we don't want to * randomly drop data for eg socket -> socket splicing. Use the * piped splicing for that! */ |
496ad9aa8 new helper: file_... |
872 |
i_mode = file_inode(in)->i_mode; |
b92ce5589 [PATCH] splice: a... |
873 874 875 876 877 878 879 880 |
if (unlikely(!S_ISREG(i_mode) && !S_ISBLK(i_mode))) return -EINVAL; /* * neither in nor out is a pipe, setup an internal pipe attached to * 'out' and transfer the wanted data from 'in' to 'out' through that */ pipe = current->splice_pipe; |
49570e9b2 [PATCH] splice: u... |
881 |
if (unlikely(!pipe)) { |
7bee130e2 get rid of alloc_... |
882 |
pipe = alloc_pipe_info(); |
b92ce5589 [PATCH] splice: a... |
883 884 885 886 887 |
if (!pipe) return -ENOMEM; /* * We don't have an immediate reader, but we'll read the stuff |
00522fb41 [PATCH] splice: r... |
888 |
* out of the pipe right after the splice_to_pipe(). So set |
b92ce5589 [PATCH] splice: a... |
889 890 891 892 893 894 895 896 |
* PIPE_READERS appropriately. */ pipe->readers = 1; current->splice_pipe = pipe; } /* |
73d62d83e [PATCH] splice: c... |
897 |
* Do the splice. |
b92ce5589 [PATCH] splice: a... |
898 899 900 |
*/ ret = 0; bytes = 0; |
c66ab6fa7 splice: abstract ... |
901 902 903 904 905 906 907 |
len = sd->total_len; flags = sd->flags; /* * Don't block on output, we have to drain the direct pipe. */ sd->flags &= ~SPLICE_F_NONBLOCK; |
0ff28d9f4 splice: sendfile(... |
908 |
more = sd->flags & SPLICE_F_MORE; |
b92ce5589 [PATCH] splice: a... |
909 910 |
while (len) { |
51a92c0f6 splice: fix offse... |
911 |
size_t read_len; |
a82c53a0e splice: fix sendf... |
912 |
loff_t pos = sd->pos, prev_pos = pos; |
b92ce5589 [PATCH] splice: a... |
913 |
|
bcd4f3acb splice: direct sp... |
914 |
ret = do_splice_to(in, &pos, pipe, len, flags); |
51a92c0f6 splice: fix offse... |
915 |
if (unlikely(ret <= 0)) |
b92ce5589 [PATCH] splice: a... |
916 917 918 |
goto out_release; read_len = ret; |
c66ab6fa7 splice: abstract ... |
919 |
sd->total_len = read_len; |
b92ce5589 [PATCH] splice: a... |
920 921 |
/* |
0ff28d9f4 splice: sendfile(... |
922 923 924 925 926 927 928 929 930 |
* If more data is pending, set SPLICE_F_MORE * If this is the last data and SPLICE_F_MORE was not set * initially, clears it. */ if (read_len < len) sd->flags |= SPLICE_F_MORE; else if (!more) sd->flags &= ~SPLICE_F_MORE; /* |
b92ce5589 [PATCH] splice: a... |
931 932 933 934 |
* NOTE: nonblocking mode only applies to the input. We * must not do the output in nonblocking mode as then we * could get stuck data in the internal pipe: */ |
c66ab6fa7 splice: abstract ... |
935 |
ret = actor(pipe, sd); |
a82c53a0e splice: fix sendf... |
936 937 |
if (unlikely(ret <= 0)) { sd->pos = prev_pos; |
b92ce5589 [PATCH] splice: a... |
938 |
goto out_release; |
a82c53a0e splice: fix sendf... |
939 |
} |
b92ce5589 [PATCH] splice: a... |
940 941 942 |
bytes += ret; len -= ret; |
bcd4f3acb splice: direct sp... |
943 |
sd->pos = pos; |
b92ce5589 [PATCH] splice: a... |
944 |
|
a82c53a0e splice: fix sendf... |
945 946 |
if (ret < read_len) { sd->pos = prev_pos + ret; |
51a92c0f6 splice: fix offse... |
947 |
goto out_release; |
a82c53a0e splice: fix sendf... |
948 |
} |
b92ce5589 [PATCH] splice: a... |
949 |
} |
9e97198db splice: fix probl... |
950 |
done: |
b92ce5589 [PATCH] splice: a... |
951 |
pipe->nrbufs = pipe->curbuf = 0; |
808487085 splice: always up... |
952 |
file_accessed(in); |
b92ce5589 [PATCH] splice: a... |
953 954 955 956 957 958 959 |
return bytes; out_release: /* * If we did an incomplete transfer we must release * the pipe buffers in question: */ |
35f3d14db pipe: add support... |
960 |
for (i = 0; i < pipe->buffers; i++) { |
b92ce5589 [PATCH] splice: a... |
961 |
struct pipe_buffer *buf = pipe->bufs + i; |
a779638cf pipe: add pipe_bu... |
962 963 |
if (buf->ops) pipe_buf_release(pipe, buf); |
b92ce5589 [PATCH] splice: a... |
964 |
} |
b92ce5589 [PATCH] splice: a... |
965 |
|
9e97198db splice: fix probl... |
966 967 |
if (!bytes) bytes = ret; |
c66ab6fa7 splice: abstract ... |
968 |
|
9e97198db splice: fix probl... |
969 |
goto done; |
c66ab6fa7 splice: abstract ... |
970 971 972 973 974 975 |
} EXPORT_SYMBOL(splice_direct_to_actor); static int direct_splice_actor(struct pipe_inode_info *pipe, struct splice_desc *sd) { |
6a14b90bb vmsplice: add vms... |
976 |
struct file *file = sd->u.file; |
c66ab6fa7 splice: abstract ... |
977 |
|
7995bd287 splice: don't pas... |
978 |
return do_splice_from(pipe, file, sd->opos, sd->total_len, |
2cb4b05e7 splice: direct_sp... |
979 |
sd->flags); |
c66ab6fa7 splice: abstract ... |
980 |
} |
932cc6d4f splice: completel... |
981 982 983 984 985 |
/** * do_splice_direct - splices data directly between two files * @in: file to splice from * @ppos: input file offset * @out: file to splice to |
acdb37c36 fs: fix new splic... |
986 |
* @opos: output file offset |
932cc6d4f splice: completel... |
987 988 989 990 991 992 993 994 995 996 |
* @len: number of bytes to splice * @flags: splice modifier flags * * Description: * For use by do_sendfile(). splice can easily emulate sendfile, but * doing it in the application would incur an extra system call * (splice in + splice out, as compared to just sendfile()). So this helper * can splice directly through a process-private pipe. * */ |
c66ab6fa7 splice: abstract ... |
997 |
long do_splice_direct(struct file *in, loff_t *ppos, struct file *out, |
7995bd287 splice: don't pas... |
998 |
loff_t *opos, size_t len, unsigned int flags) |
c66ab6fa7 splice: abstract ... |
999 1000 1001 1002 1003 1004 |
{ struct splice_desc sd = { .len = len, .total_len = len, .flags = flags, .pos = *ppos, |
6a14b90bb vmsplice: add vms... |
1005 |
.u.file = out, |
7995bd287 splice: don't pas... |
1006 |
.opos = opos, |
c66ab6fa7 splice: abstract ... |
1007 |
}; |
51a92c0f6 splice: fix offse... |
1008 |
long ret; |
c66ab6fa7 splice: abstract ... |
1009 |
|
18c67cb9f splice: lift chec... |
1010 1011 1012 1013 1014 1015 1016 1017 1018 |
if (unlikely(!(out->f_mode & FMODE_WRITE))) return -EBADF; if (unlikely(out->f_flags & O_APPEND)) return -EINVAL; ret = rw_verify_area(WRITE, out, opos, len); if (unlikely(ret < 0)) return ret; |
c66ab6fa7 splice: abstract ... |
1019 |
ret = splice_direct_to_actor(in, &sd, direct_splice_actor); |
51a92c0f6 splice: fix offse... |
1020 |
if (ret > 0) |
a82c53a0e splice: fix sendf... |
1021 |
*ppos = sd.pos; |
51a92c0f6 splice: fix offse... |
1022 |
|
c66ab6fa7 splice: abstract ... |
1023 |
return ret; |
b92ce5589 [PATCH] splice: a... |
1024 |
} |
1c118596a vfs: export do_sp... |
1025 |
EXPORT_SYMBOL(do_splice_direct); |
b92ce5589 [PATCH] splice: a... |
1026 |
|
8924feff6 splice: lift pipe... |
1027 1028 |
static int wait_for_space(struct pipe_inode_info *pipe, unsigned flags) { |
52bce9116 splice: reinstate... |
1029 1030 1031 1032 1033 1034 1035 |
for (;;) { if (unlikely(!pipe->readers)) { send_sig(SIGPIPE, current, 0); return -EPIPE; } if (pipe->nrbufs != pipe->buffers) return 0; |
8924feff6 splice: lift pipe... |
1036 1037 1038 1039 1040 1041 1042 1043 |
if (flags & SPLICE_F_NONBLOCK) return -EAGAIN; if (signal_pending(current)) return -ERESTARTSYS; pipe->waiting_writers++; pipe_wait(pipe); pipe->waiting_writers--; } |
8924feff6 splice: lift pipe... |
1044 |
} |
7c77f0b3f splice: implement... |
1045 1046 1047 |
static int splice_pipe_to_pipe(struct pipe_inode_info *ipipe, struct pipe_inode_info *opipe, size_t len, unsigned int flags); |
ddac0d39c [PATCH] splice: f... |
1048 1049 |
/* |
83f9135bd [PATCH] splice: a... |
1050 1051 |
* Determine where to splice to/from. */ |
529565dcb [PATCH] splice: a... |
1052 1053 1054 |
static long do_splice(struct file *in, loff_t __user *off_in, struct file *out, loff_t __user *off_out, size_t len, unsigned int flags) |
5274f052e [PATCH] Introduce... |
1055 |
{ |
7c77f0b3f splice: implement... |
1056 1057 |
struct pipe_inode_info *ipipe; struct pipe_inode_info *opipe; |
7995bd287 splice: don't pas... |
1058 |
loff_t offset; |
a4514ebd8 [PATCH] splice: o... |
1059 |
long ret; |
5274f052e [PATCH] Introduce... |
1060 |
|
71993e62a Rename 'pipe_info... |
1061 1062 |
ipipe = get_pipe_info(in); opipe = get_pipe_info(out); |
7c77f0b3f splice: implement... |
1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 |
if (ipipe && opipe) { if (off_in || off_out) return -ESPIPE; if (!(in->f_mode & FMODE_READ)) return -EBADF; if (!(out->f_mode & FMODE_WRITE)) return -EBADF; /* Splicing to self would be fun, but... */ if (ipipe == opipe) return -EINVAL; return splice_pipe_to_pipe(ipipe, opipe, len, flags); } if (ipipe) { |
529565dcb [PATCH] splice: a... |
1082 1083 |
if (off_in) return -ESPIPE; |
b92ce5589 [PATCH] splice: a... |
1084 |
if (off_out) { |
19c9a49b4 splice: check f_m... |
1085 |
if (!(out->f_mode & FMODE_PWRITE)) |
b92ce5589 [PATCH] splice: a... |
1086 |
return -EINVAL; |
cbb7e577e [PATCH] splice: p... |
1087 |
if (copy_from_user(&offset, off_out, sizeof(loff_t))) |
b92ce5589 [PATCH] splice: a... |
1088 |
return -EFAULT; |
7995bd287 splice: don't pas... |
1089 1090 1091 |
} else { offset = out->f_pos; } |
529565dcb [PATCH] splice: a... |
1092 |
|
18c67cb9f splice: lift chec... |
1093 1094 1095 1096 1097 1098 1099 1100 1101 |
if (unlikely(!(out->f_mode & FMODE_WRITE))) return -EBADF; if (unlikely(out->f_flags & O_APPEND)) return -EINVAL; ret = rw_verify_area(WRITE, out, &offset, len); if (unlikely(ret < 0)) return ret; |
500368f7f lift file_*_write... |
1102 |
file_start_write(out); |
7995bd287 splice: don't pas... |
1103 |
ret = do_splice_from(ipipe, out, &offset, len, flags); |
500368f7f lift file_*_write... |
1104 |
file_end_write(out); |
a4514ebd8 [PATCH] splice: o... |
1105 |
|
7995bd287 splice: don't pas... |
1106 1107 1108 |
if (!off_out) out->f_pos = offset; else if (copy_to_user(off_out, &offset, sizeof(loff_t))) |
a4514ebd8 [PATCH] splice: o... |
1109 1110 1111 |
ret = -EFAULT; return ret; |
529565dcb [PATCH] splice: a... |
1112 |
} |
5274f052e [PATCH] Introduce... |
1113 |
|
7c77f0b3f splice: implement... |
1114 |
if (opipe) { |
529565dcb [PATCH] splice: a... |
1115 1116 |
if (off_out) return -ESPIPE; |
b92ce5589 [PATCH] splice: a... |
1117 |
if (off_in) { |
19c9a49b4 splice: check f_m... |
1118 |
if (!(in->f_mode & FMODE_PREAD)) |
b92ce5589 [PATCH] splice: a... |
1119 |
return -EINVAL; |
cbb7e577e [PATCH] splice: p... |
1120 |
if (copy_from_user(&offset, off_in, sizeof(loff_t))) |
b92ce5589 [PATCH] splice: a... |
1121 |
return -EFAULT; |
7995bd287 splice: don't pas... |
1122 1123 1124 |
} else { offset = in->f_pos; } |
529565dcb [PATCH] splice: a... |
1125 |
|
8924feff6 splice: lift pipe... |
1126 1127 1128 1129 1130 1131 1132 |
pipe_lock(opipe); ret = wait_for_space(opipe, flags); if (!ret) ret = do_splice_to(in, &offset, opipe, len, flags); pipe_unlock(opipe); if (ret > 0) wakeup_pipe_readers(opipe); |
7995bd287 splice: don't pas... |
1133 1134 1135 |
if (!off_in) in->f_pos = offset; else if (copy_to_user(off_in, &offset, sizeof(loff_t))) |
a4514ebd8 [PATCH] splice: o... |
1136 1137 1138 |
ret = -EFAULT; return ret; |
529565dcb [PATCH] splice: a... |
1139 |
} |
5274f052e [PATCH] Introduce... |
1140 1141 1142 |
return -EINVAL; } |
79fddc4ef new helper: add_t... |
1143 1144 1145 |
static int iter_to_pipe(struct iov_iter *from, struct pipe_inode_info *pipe, unsigned flags) |
912d35f86 [PATCH] Add suppo... |
1146 |
{ |
79fddc4ef new helper: add_t... |
1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 |
struct pipe_buffer buf = { .ops = &user_page_pipe_buf_ops, .flags = flags }; size_t total = 0; int ret = 0; bool failed = false; while (iov_iter_count(from) && !failed) { struct page *pages[16]; |
db85a9eb2 splice: switch ge... |
1157 1158 |
ssize_t copied; size_t start; |
79fddc4ef new helper: add_t... |
1159 |
int n; |
db85a9eb2 splice: switch ge... |
1160 |
|
79fddc4ef new helper: add_t... |
1161 1162 1163 1164 1165 |
copied = iov_iter_get_pages(from, pages, ~0UL, 16, &start); if (copied <= 0) { ret = copied; break; } |
db85a9eb2 splice: switch ge... |
1166 |
|
79fddc4ef new helper: add_t... |
1167 |
for (n = 0; copied; n++, start = 0) { |
db85a9eb2 splice: switch ge... |
1168 |
int size = min_t(int, copied, PAGE_SIZE - start); |
79fddc4ef new helper: add_t... |
1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 |
if (!failed) { buf.page = pages[n]; buf.offset = start; buf.len = size; ret = add_to_pipe(pipe, &buf); if (unlikely(ret < 0)) { failed = true; } else { iov_iter_advance(from, ret); total += ret; } } else { put_page(pages[n]); } |
db85a9eb2 splice: switch ge... |
1183 |
copied -= size; |
912d35f86 [PATCH] Add suppo... |
1184 |
} |
912d35f86 [PATCH] Add suppo... |
1185 |
} |
79fddc4ef new helper: add_t... |
1186 |
return total ? total : ret; |
912d35f86 [PATCH] Add suppo... |
1187 |
} |
6a14b90bb vmsplice: add vms... |
1188 1189 1190 |
static int pipe_to_user(struct pipe_inode_info *pipe, struct pipe_buffer *buf, struct splice_desc *sd) { |
6130f5315 switch vmsplice_t... |
1191 1192 |
int n = copy_page_to_iter(buf->page, buf->offset, sd->len, sd->u.data); return n == sd->len ? n : -EFAULT; |
6a14b90bb vmsplice: add vms... |
1193 1194 1195 1196 1197 1198 |
} /* * For lack of a better implementation, implement vmsplice() to userspace * as a simple copy of the pipes pages to the user iov. */ |
87a3002af vmsplice(): lift ... |
1199 1200 |
static long vmsplice_to_user(struct file *file, struct iov_iter *iter, unsigned int flags) |
6a14b90bb vmsplice: add vms... |
1201 |
{ |
87a3002af vmsplice(): lift ... |
1202 1203 1204 1205 1206 1207 1208 |
struct pipe_inode_info *pipe = get_pipe_info(file); struct splice_desc sd = { .total_len = iov_iter_count(iter), .flags = flags, .u.data = iter }; long ret = 0; |
6a14b90bb vmsplice: add vms... |
1209 |
|
6a14b90bb vmsplice: add vms... |
1210 1211 |
if (!pipe) return -EBADF; |
345995fa4 vmsplice_to_user(... |
1212 1213 1214 1215 1216 |
if (sd.total_len) { pipe_lock(pipe); ret = __splice_from_pipe(pipe, &sd, pipe_to_user); pipe_unlock(pipe); } |
6a14b90bb vmsplice: add vms... |
1217 1218 1219 |
return ret; } |
912d35f86 [PATCH] Add suppo... |
1220 1221 1222 1223 |
/* * vmsplice splices a user address range into a pipe. It can be thought of * as splice-from-memory, where the regular splice is splice-from-file (or * to file). In both cases the output is a pipe, naturally. |
912d35f86 [PATCH] Add suppo... |
1224 |
*/ |
87a3002af vmsplice(): lift ... |
1225 1226 |
static long vmsplice_to_pipe(struct file *file, struct iov_iter *iter, unsigned int flags) |
912d35f86 [PATCH] Add suppo... |
1227 |
{ |
ddac0d39c [PATCH] splice: f... |
1228 |
struct pipe_inode_info *pipe; |
87a3002af vmsplice(): lift ... |
1229 |
long ret = 0; |
79fddc4ef new helper: add_t... |
1230 1231 1232 1233 |
unsigned buf_flag = 0; if (flags & SPLICE_F_GIFT) buf_flag = PIPE_BUF_FLAG_GIFT; |
912d35f86 [PATCH] Add suppo... |
1234 |
|
71993e62a Rename 'pipe_info... |
1235 |
pipe = get_pipe_info(file); |
ddac0d39c [PATCH] splice: f... |
1236 |
if (!pipe) |
912d35f86 [PATCH] Add suppo... |
1237 |
return -EBADF; |
912d35f86 [PATCH] Add suppo... |
1238 |
|
8924feff6 splice: lift pipe... |
1239 1240 |
pipe_lock(pipe); ret = wait_for_space(pipe, flags); |
79fddc4ef new helper: add_t... |
1241 |
if (!ret) |
87a3002af vmsplice(): lift ... |
1242 |
ret = iter_to_pipe(iter, pipe, buf_flag); |
8924feff6 splice: lift pipe... |
1243 1244 1245 |
pipe_unlock(pipe); if (ret > 0) wakeup_pipe_readers(pipe); |
35f3d14db pipe: add support... |
1246 |
return ret; |
912d35f86 [PATCH] Add suppo... |
1247 |
} |
87a3002af vmsplice(): lift ... |
1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 |
static int vmsplice_type(struct fd f, int *type) { if (!f.file) return -EBADF; if (f.file->f_mode & FMODE_WRITE) { *type = WRITE; } else if (f.file->f_mode & FMODE_READ) { *type = READ; } else { fdput(f); return -EBADF; } return 0; } |
6a14b90bb vmsplice: add vms... |
1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 |
/* * Note that vmsplice only really supports true splicing _from_ user memory * to a pipe, not the other way around. Splicing from user memory is a simple * operation that can be supported without any funky alignment restrictions * or nasty vm tricks. We simply map in the user memory and fill them into * a pipe. The reverse isn't quite as easy, though. There are two possible * solutions for that: * * - memcpy() the data internally, at which point we might as well just * do a regular read() on the buffer anyway. * - Lots of nasty vm tricks, that are neither fast nor flexible (it * has restriction limitations on both ends of the pipe). * * Currently we punt and implement it as a normal copy, see pipe_to_user(). * */ |
87a3002af vmsplice(): lift ... |
1278 |
static long do_vmsplice(struct file *f, struct iov_iter *iter, unsigned int flags) |
912d35f86 [PATCH] Add suppo... |
1279 |
{ |
3d6ea290f splice/tee/vmspli... |
1280 1281 |
if (unlikely(flags & ~SPLICE_F_ALL)) return -EINVAL; |
6a14b90bb vmsplice: add vms... |
1282 |
|
87a3002af vmsplice(): lift ... |
1283 1284 |
if (!iov_iter_count(iter)) return 0; |
912d35f86 [PATCH] Add suppo... |
1285 |
|
87a3002af vmsplice(): lift ... |
1286 1287 1288 1289 |
if (iov_iter_rw(iter) == WRITE) return vmsplice_to_pipe(f, iter, flags); else return vmsplice_to_user(f, iter, flags); |
912d35f86 [PATCH] Add suppo... |
1290 |
} |
87a3002af vmsplice(): lift ... |
1291 |
SYSCALL_DEFINE4(vmsplice, int, fd, const struct iovec __user *, uiov, |
30cfe4ef8 fs: add do_vmspli... |
1292 1293 |
unsigned long, nr_segs, unsigned int, flags) { |
87a3002af vmsplice(): lift ... |
1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 |
struct iovec iovstack[UIO_FASTIOV]; struct iovec *iov = iovstack; struct iov_iter iter; long error; struct fd f; int type; f = fdget(fd); error = vmsplice_type(f, &type); if (error) return error; error = import_iovec(type, uiov, nr_segs, ARRAY_SIZE(iovstack), &iov, &iter); if (!error) { error = do_vmsplice(f.file, &iter, flags); kfree(iov); } fdput(f); return error; |
30cfe4ef8 fs: add do_vmspli... |
1314 |
} |
76b021d05 convert vmsplice ... |
1315 1316 1317 1318 |
#ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE4(vmsplice, int, fd, const struct compat_iovec __user *, iov32, unsigned int, nr_segs, unsigned int, flags) { |
87a3002af vmsplice(): lift ... |
1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 |
struct iovec iovstack[UIO_FASTIOV]; struct iovec *iov = iovstack; struct iov_iter iter; long error; struct fd f; int type; f = fdget(fd); error = vmsplice_type(f, &type); if (error) return error; error = compat_import_iovec(type, iov32, nr_segs, ARRAY_SIZE(iovstack), &iov, &iter); if (!error) { error = do_vmsplice(f.file, &iter, flags); kfree(iov); |
76b021d05 convert vmsplice ... |
1336 |
} |
87a3002af vmsplice(): lift ... |
1337 1338 |
fdput(f); return error; |
76b021d05 convert vmsplice ... |
1339 1340 |
} #endif |
836f92adf [CVE-2009-0029] S... |
1341 1342 1343 |
SYSCALL_DEFINE6(splice, int, fd_in, loff_t __user *, off_in, int, fd_out, loff_t __user *, off_out, size_t, len, unsigned int, flags) |
5274f052e [PATCH] Introduce... |
1344 |
{ |
2903ff019 switch simple cas... |
1345 |
struct fd in, out; |
5274f052e [PATCH] Introduce... |
1346 |
long error; |
5274f052e [PATCH] Introduce... |
1347 1348 1349 |
if (unlikely(!len)) return 0; |
3d6ea290f splice/tee/vmspli... |
1350 1351 |
if (unlikely(flags & ~SPLICE_F_ALL)) return -EINVAL; |
5274f052e [PATCH] Introduce... |
1352 |
error = -EBADF; |
2903ff019 switch simple cas... |
1353 1354 1355 1356 1357 1358 1359 1360 |
in = fdget(fd_in); if (in.file) { if (in.file->f_mode & FMODE_READ) { out = fdget(fd_out); if (out.file) { if (out.file->f_mode & FMODE_WRITE) error = do_splice(in.file, off_in, out.file, off_out, |
529565dcb [PATCH] splice: a... |
1361 |
len, flags); |
2903ff019 switch simple cas... |
1362 |
fdput(out); |
5274f052e [PATCH] Introduce... |
1363 1364 |
} } |
2903ff019 switch simple cas... |
1365 |
fdput(in); |
5274f052e [PATCH] Introduce... |
1366 |
} |
5274f052e [PATCH] Introduce... |
1367 1368 |
return error; } |
70524490e [PATCH] splice: a... |
1369 1370 |
/* |
aadd06e5c [PATCH] splice: f... |
1371 1372 1373 |
* Make sure there's data to read. Wait for input if we can, otherwise * return an appropriate error. */ |
7c77f0b3f splice: implement... |
1374 |
static int ipipe_prep(struct pipe_inode_info *pipe, unsigned int flags) |
aadd06e5c [PATCH] splice: f... |
1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 |
{ int ret; /* * Check ->nrbufs without the inode lock first. This function * is speculative anyways, so missing one is ok. */ if (pipe->nrbufs) return 0; ret = 0; |
61e0d47c3 splice: add helpe... |
1386 |
pipe_lock(pipe); |
aadd06e5c [PATCH] splice: f... |
1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 |
while (!pipe->nrbufs) { if (signal_pending(current)) { ret = -ERESTARTSYS; break; } if (!pipe->writers) break; if (!pipe->waiting_writers) { if (flags & SPLICE_F_NONBLOCK) { ret = -EAGAIN; break; } } pipe_wait(pipe); } |
61e0d47c3 splice: add helpe... |
1403 |
pipe_unlock(pipe); |
aadd06e5c [PATCH] splice: f... |
1404 1405 1406 1407 1408 1409 1410 |
return ret; } /* * Make sure there's writeable room. Wait for room if we can, otherwise * return an appropriate error. */ |
7c77f0b3f splice: implement... |
1411 |
static int opipe_prep(struct pipe_inode_info *pipe, unsigned int flags) |
aadd06e5c [PATCH] splice: f... |
1412 1413 1414 1415 1416 1417 1418 |
{ int ret; /* * Check ->nrbufs without the inode lock first. This function * is speculative anyways, so missing one is ok. */ |
35f3d14db pipe: add support... |
1419 |
if (pipe->nrbufs < pipe->buffers) |
aadd06e5c [PATCH] splice: f... |
1420 1421 1422 |
return 0; ret = 0; |
61e0d47c3 splice: add helpe... |
1423 |
pipe_lock(pipe); |
aadd06e5c [PATCH] splice: f... |
1424 |
|
35f3d14db pipe: add support... |
1425 |
while (pipe->nrbufs >= pipe->buffers) { |
aadd06e5c [PATCH] splice: f... |
1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 |
if (!pipe->readers) { send_sig(SIGPIPE, current, 0); ret = -EPIPE; break; } if (flags & SPLICE_F_NONBLOCK) { ret = -EAGAIN; break; } if (signal_pending(current)) { ret = -ERESTARTSYS; break; } pipe->waiting_writers++; pipe_wait(pipe); pipe->waiting_writers--; } |
61e0d47c3 splice: add helpe... |
1443 |
pipe_unlock(pipe); |
aadd06e5c [PATCH] splice: f... |
1444 1445 1446 1447 |
return ret; } /* |
7c77f0b3f splice: implement... |
1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 |
* Splice contents of ipipe to opipe. */ static int splice_pipe_to_pipe(struct pipe_inode_info *ipipe, struct pipe_inode_info *opipe, size_t len, unsigned int flags) { struct pipe_buffer *ibuf, *obuf; int ret = 0, nbuf; bool input_wakeup = false; retry: ret = ipipe_prep(ipipe, flags); if (ret) return ret; ret = opipe_prep(opipe, flags); if (ret) return ret; /* * Potential ABBA deadlock, work around it by ordering lock * grabbing by pipe info address. Otherwise two different processes * could deadlock (one doing tee from A -> B, the other from B -> A). */ pipe_double_lock(ipipe, opipe); do { if (!opipe->readers) { send_sig(SIGPIPE, current, 0); if (!ret) ret = -EPIPE; break; } if (!ipipe->nrbufs && !ipipe->writers) break; /* * Cannot make any progress, because either the input * pipe is empty or the output pipe is full. */ |
35f3d14db pipe: add support... |
1490 |
if (!ipipe->nrbufs || opipe->nrbufs >= opipe->buffers) { |
7c77f0b3f splice: implement... |
1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 |
/* Already processed some buffers, break */ if (ret) break; if (flags & SPLICE_F_NONBLOCK) { ret = -EAGAIN; break; } /* * We raced with another reader/writer and haven't * managed to process any buffers. A zero return * value means EOF, so retry instead. */ pipe_unlock(ipipe); pipe_unlock(opipe); goto retry; } ibuf = ipipe->bufs + ipipe->curbuf; |
35f3d14db pipe: add support... |
1511 |
nbuf = (opipe->curbuf + opipe->nrbufs) & (opipe->buffers - 1); |
7c77f0b3f splice: implement... |
1512 1513 1514 1515 1516 1517 1518 1519 1520 |
obuf = opipe->bufs + nbuf; if (len >= ibuf->len) { /* * Simply move the whole buffer from ipipe to opipe */ *obuf = *ibuf; ibuf->ops = NULL; opipe->nrbufs++; |
35f3d14db pipe: add support... |
1521 |
ipipe->curbuf = (ipipe->curbuf + 1) & (ipipe->buffers - 1); |
7c77f0b3f splice: implement... |
1522 1523 1524 1525 1526 1527 1528 |
ipipe->nrbufs--; input_wakeup = true; } else { /* * Get a reference to this pipe buffer, * so we can copy the contents over. */ |
7bf2d1df8 pipe: add pipe_bu... |
1529 |
pipe_buf_get(ipipe, ibuf); |
7c77f0b3f splice: implement... |
1530 1531 1532 1533 1534 1535 1536 |
*obuf = *ibuf; /* * Don't inherit the gift flag, we need to * prevent multiple steals of this page. */ obuf->flags &= ~PIPE_BUF_FLAG_GIFT; |
2af926fd5 splice: don't mer... |
1537 |
pipe_buf_mark_unmergeable(obuf); |
7c77f0b3f splice: implement... |
1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 |
obuf->len = len; opipe->nrbufs++; ibuf->offset += obuf->len; ibuf->len -= obuf->len; } ret += obuf->len; len -= obuf->len; } while (len); pipe_unlock(ipipe); pipe_unlock(opipe); /* * If we put data in the output pipe, wakeup any potential readers. */ |
825cdcb1a splice: add wakeu... |
1553 1554 |
if (ret > 0) wakeup_pipe_readers(opipe); |
7c77f0b3f splice: implement... |
1555 1556 1557 1558 1559 1560 1561 |
if (input_wakeup) wakeup_pipe_writers(ipipe); return ret; } /* |
70524490e [PATCH] splice: a... |
1562 1563 1564 1565 1566 1567 1568 |
* Link contents of ipipe to opipe. */ static int link_pipe(struct pipe_inode_info *ipipe, struct pipe_inode_info *opipe, size_t len, unsigned int flags) { struct pipe_buffer *ibuf, *obuf; |
aadd06e5c [PATCH] splice: f... |
1569 |
int ret = 0, i = 0, nbuf; |
70524490e [PATCH] splice: a... |
1570 1571 1572 |
/* * Potential ABBA deadlock, work around it by ordering lock |
61e0d47c3 splice: add helpe... |
1573 |
* grabbing by pipe info address. Otherwise two different processes |
70524490e [PATCH] splice: a... |
1574 1575 |
* could deadlock (one doing tee from A -> B, the other from B -> A). */ |
61e0d47c3 splice: add helpe... |
1576 |
pipe_double_lock(ipipe, opipe); |
70524490e [PATCH] splice: a... |
1577 |
|
aadd06e5c [PATCH] splice: f... |
1578 |
do { |
70524490e [PATCH] splice: a... |
1579 1580 1581 1582 1583 1584 |
if (!opipe->readers) { send_sig(SIGPIPE, current, 0); if (!ret) ret = -EPIPE; break; } |
70524490e [PATCH] splice: a... |
1585 |
|
aadd06e5c [PATCH] splice: f... |
1586 1587 1588 1589 |
/* * If we have iterated all input buffers or ran out of * output room, break. */ |
35f3d14db pipe: add support... |
1590 |
if (i >= ipipe->nrbufs || opipe->nrbufs >= opipe->buffers) |
aadd06e5c [PATCH] splice: f... |
1591 |
break; |
70524490e [PATCH] splice: a... |
1592 |
|
35f3d14db pipe: add support... |
1593 1594 |
ibuf = ipipe->bufs + ((ipipe->curbuf + i) & (ipipe->buffers-1)); nbuf = (opipe->curbuf + opipe->nrbufs) & (opipe->buffers - 1); |
70524490e [PATCH] splice: a... |
1595 1596 |
/* |
aadd06e5c [PATCH] splice: f... |
1597 1598 |
* Get a reference to this pipe buffer, * so we can copy the contents over. |
70524490e [PATCH] splice: a... |
1599 |
*/ |
7bf2d1df8 pipe: add pipe_bu... |
1600 |
pipe_buf_get(ipipe, ibuf); |
aadd06e5c [PATCH] splice: f... |
1601 1602 1603 |
obuf = opipe->bufs + nbuf; *obuf = *ibuf; |
2a27250e6 [PATCH] tee: link... |
1604 |
/* |
aadd06e5c [PATCH] splice: f... |
1605 1606 |
* Don't inherit the gift flag, we need to * prevent multiple steals of this page. |
2a27250e6 [PATCH] tee: link... |
1607 |
*/ |
aadd06e5c [PATCH] splice: f... |
1608 |
obuf->flags &= ~PIPE_BUF_FLAG_GIFT; |
70524490e [PATCH] splice: a... |
1609 |
|
2af926fd5 splice: don't mer... |
1610 |
pipe_buf_mark_unmergeable(obuf); |
aadd06e5c [PATCH] splice: f... |
1611 1612 |
if (obuf->len > len) obuf->len = len; |
70524490e [PATCH] splice: a... |
1613 |
|
aadd06e5c [PATCH] splice: f... |
1614 1615 1616 1617 1618 |
opipe->nrbufs++; ret += obuf->len; len -= obuf->len; i++; } while (len); |
70524490e [PATCH] splice: a... |
1619 |
|
02cf01aea splice: only retu... |
1620 1621 1622 1623 1624 1625 |
/* * return EAGAIN if we have the potential of some data in the * future, otherwise just return 0 */ if (!ret && ipipe->waiting_writers && (flags & SPLICE_F_NONBLOCK)) ret = -EAGAIN; |
61e0d47c3 splice: add helpe... |
1626 1627 |
pipe_unlock(ipipe); pipe_unlock(opipe); |
70524490e [PATCH] splice: a... |
1628 |
|
aadd06e5c [PATCH] splice: f... |
1629 1630 1631 |
/* * If we put data in the output pipe, wakeup any potential readers. */ |
825cdcb1a splice: add wakeu... |
1632 1633 |
if (ret > 0) wakeup_pipe_readers(opipe); |
70524490e [PATCH] splice: a... |
1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 |
return ret; } /* * This is a tee(1) implementation that works on pipes. It doesn't copy * any data, it simply references the 'in' pages on the 'out' pipe. * The 'flags' used are the SPLICE_F_* variants, currently the only * applicable one is SPLICE_F_NONBLOCK. */ static long do_tee(struct file *in, struct file *out, size_t len, unsigned int flags) { |
71993e62a Rename 'pipe_info... |
1647 1648 |
struct pipe_inode_info *ipipe = get_pipe_info(in); struct pipe_inode_info *opipe = get_pipe_info(out); |
aadd06e5c [PATCH] splice: f... |
1649 |
int ret = -EINVAL; |
70524490e [PATCH] splice: a... |
1650 1651 |
/* |
aadd06e5c [PATCH] splice: f... |
1652 1653 |
* Duplicate the contents of ipipe to opipe without actually * copying the data. |
70524490e [PATCH] splice: a... |
1654 |
*/ |
aadd06e5c [PATCH] splice: f... |
1655 1656 1657 1658 1659 |
if (ipipe && opipe && ipipe != opipe) { /* * Keep going, unless we encounter an error. The ipipe/opipe * ordering doesn't really matter. */ |
7c77f0b3f splice: implement... |
1660 |
ret = ipipe_prep(ipipe, flags); |
aadd06e5c [PATCH] splice: f... |
1661 |
if (!ret) { |
7c77f0b3f splice: implement... |
1662 |
ret = opipe_prep(opipe, flags); |
02cf01aea splice: only retu... |
1663 |
if (!ret) |
aadd06e5c [PATCH] splice: f... |
1664 |
ret = link_pipe(ipipe, opipe, len, flags); |
aadd06e5c [PATCH] splice: f... |
1665 1666 |
} } |
70524490e [PATCH] splice: a... |
1667 |
|
aadd06e5c [PATCH] splice: f... |
1668 |
return ret; |
70524490e [PATCH] splice: a... |
1669 |
} |
836f92adf [CVE-2009-0029] S... |
1670 |
SYSCALL_DEFINE4(tee, int, fdin, int, fdout, size_t, len, unsigned int, flags) |
70524490e [PATCH] splice: a... |
1671 |
{ |
2903ff019 switch simple cas... |
1672 1673 |
struct fd in; int error; |
70524490e [PATCH] splice: a... |
1674 |
|
3d6ea290f splice/tee/vmspli... |
1675 1676 |
if (unlikely(flags & ~SPLICE_F_ALL)) return -EINVAL; |
70524490e [PATCH] splice: a... |
1677 1678 1679 1680 |
if (unlikely(!len)) return 0; error = -EBADF; |
2903ff019 switch simple cas... |
1681 1682 1683 1684 1685 1686 1687 1688 1689 |
in = fdget(fdin); if (in.file) { if (in.file->f_mode & FMODE_READ) { struct fd out = fdget(fdout); if (out.file) { if (out.file->f_mode & FMODE_WRITE) error = do_tee(in.file, out.file, len, flags); fdput(out); |
70524490e [PATCH] splice: a... |
1690 1691 |
} } |
2903ff019 switch simple cas... |
1692 |
fdput(in); |
70524490e [PATCH] splice: a... |
1693 1694 1695 1696 |
} return error; } |