15274f052SJens Axboe /* 25274f052SJens Axboe * "splice": joining two ropes together by interweaving their strands. 35274f052SJens Axboe * 45274f052SJens Axboe * This is the "extended pipe" functionality, where a pipe is used as 55274f052SJens Axboe * an arbitrary in-memory buffer. Think of a pipe as a small kernel 65274f052SJens Axboe * buffer that you can use to transfer data from one end to the other. 75274f052SJens Axboe * 85274f052SJens Axboe * The traditional unix read/write is extended with a "splice()" operation 95274f052SJens Axboe * that transfers data buffers to or from a pipe buffer. 105274f052SJens Axboe * 115274f052SJens Axboe * Named by Larry McVoy, original implementation from Linus, extended by 12c2058e06SJens Axboe * Jens to support splicing to files, network, direct splicing, etc and 13c2058e06SJens Axboe * fixing lots of bugs. 145274f052SJens Axboe * 150fe23479SJens Axboe * Copyright (C) 2005-2006 Jens Axboe <axboe@kernel.dk> 16c2058e06SJens Axboe * Copyright (C) 2005-2006 Linus Torvalds <torvalds@osdl.org> 17c2058e06SJens Axboe * Copyright (C) 2006 Ingo Molnar <mingo@elte.hu> 185274f052SJens Axboe * 195274f052SJens Axboe */ 205274f052SJens Axboe #include <linux/fs.h> 215274f052SJens Axboe #include <linux/file.h> 225274f052SJens Axboe #include <linux/pagemap.h> 23d6b29d7cSJens Axboe #include <linux/splice.h> 245274f052SJens Axboe #include <linux/mm_inline.h> 255abc97aaSJens Axboe #include <linux/swap.h> 264f6f0bd2SJens Axboe #include <linux/writeback.h> 274f6f0bd2SJens Axboe #include <linux/buffer_head.h> 28a0f06780SJeff Garzik #include <linux/module.h> 294f6f0bd2SJens Axboe #include <linux/syscalls.h> 30912d35f8SJens Axboe #include <linux/uio.h> 315274f052SJens Axboe 3283f9135bSJens Axboe /* 3383f9135bSJens Axboe * Attempt to steal a page from a pipe buffer. This should perhaps go into 3483f9135bSJens Axboe * a vm helper function, it's already simplified quite a bit by the 3583f9135bSJens Axboe * addition of remove_mapping(). If success is returned, the caller may 3683f9135bSJens Axboe * attempt to reuse this page for another destination. 3783f9135bSJens Axboe */ 3876ad4d11SJens Axboe static int page_cache_pipe_buf_steal(struct pipe_inode_info *pipe, 395abc97aaSJens Axboe struct pipe_buffer *buf) 405abc97aaSJens Axboe { 415abc97aaSJens Axboe struct page *page = buf->page; 429e94cd4fSJens Axboe struct address_space *mapping; 435abc97aaSJens Axboe 449e0267c2SJens Axboe lock_page(page); 459e0267c2SJens Axboe 469e94cd4fSJens Axboe mapping = page_mapping(page); 479e94cd4fSJens Axboe if (mapping) { 485abc97aaSJens Axboe WARN_ON(!PageUptodate(page)); 495abc97aaSJens Axboe 50ad8d6f0aSJens Axboe /* 519e94cd4fSJens Axboe * At least for ext2 with nobh option, we need to wait on 529e94cd4fSJens Axboe * writeback completing on this page, since we'll remove it 539e94cd4fSJens Axboe * from the pagecache. Otherwise truncate wont wait on the 549e94cd4fSJens Axboe * page, allowing the disk blocks to be reused by someone else 559e94cd4fSJens Axboe * before we actually wrote our data to them. fs corruption 569e94cd4fSJens Axboe * ensues. 57ad8d6f0aSJens Axboe */ 58ad8d6f0aSJens Axboe wait_on_page_writeback(page); 59ad8d6f0aSJens Axboe 604f6f0bd2SJens Axboe if (PagePrivate(page)) 612ae88149SNick Piggin try_to_release_page(page, GFP_KERNEL); 624f6f0bd2SJens Axboe 639e94cd4fSJens Axboe /* 649e94cd4fSJens Axboe * If we succeeded in removing the mapping, set LRU flag 659e94cd4fSJens Axboe * and return good. 669e94cd4fSJens Axboe */ 679e94cd4fSJens Axboe if (remove_mapping(mapping, page)) { 681432873aSJens Axboe buf->flags |= PIPE_BUF_FLAG_LRU; 695abc97aaSJens Axboe return 0; 705abc97aaSJens Axboe } 719e94cd4fSJens Axboe } 729e94cd4fSJens Axboe 739e94cd4fSJens Axboe /* 749e94cd4fSJens Axboe * Raced with truncate or failed to remove page from current 759e94cd4fSJens Axboe * address space, unlock and return failure. 769e94cd4fSJens Axboe */ 779e94cd4fSJens Axboe unlock_page(page); 789e94cd4fSJens Axboe return 1; 799e94cd4fSJens Axboe } 805abc97aaSJens Axboe 8176ad4d11SJens Axboe static void page_cache_pipe_buf_release(struct pipe_inode_info *pipe, 825274f052SJens Axboe struct pipe_buffer *buf) 835274f052SJens Axboe { 845274f052SJens Axboe page_cache_release(buf->page); 851432873aSJens Axboe buf->flags &= ~PIPE_BUF_FLAG_LRU; 865274f052SJens Axboe } 875274f052SJens Axboe 8876ad4d11SJens Axboe static int page_cache_pipe_buf_pin(struct pipe_inode_info *pipe, 895274f052SJens Axboe struct pipe_buffer *buf) 905274f052SJens Axboe { 915274f052SJens Axboe struct page *page = buf->page; 9249d0b21bSJens Axboe int err; 935274f052SJens Axboe 945274f052SJens Axboe if (!PageUptodate(page)) { 9549d0b21bSJens Axboe lock_page(page); 965274f052SJens Axboe 9749d0b21bSJens Axboe /* 9849d0b21bSJens Axboe * Page got truncated/unhashed. This will cause a 0-byte 9973d62d83SIngo Molnar * splice, if this is the first page. 10049d0b21bSJens Axboe */ 1015274f052SJens Axboe if (!page->mapping) { 10249d0b21bSJens Axboe err = -ENODATA; 10349d0b21bSJens Axboe goto error; 1045274f052SJens Axboe } 1055274f052SJens Axboe 10649d0b21bSJens Axboe /* 10773d62d83SIngo Molnar * Uh oh, read-error from disk. 10849d0b21bSJens Axboe */ 10949d0b21bSJens Axboe if (!PageUptodate(page)) { 11049d0b21bSJens Axboe err = -EIO; 11149d0b21bSJens Axboe goto error; 11249d0b21bSJens Axboe } 11349d0b21bSJens Axboe 11449d0b21bSJens Axboe /* 115f84d7519SJens Axboe * Page is ok afterall, we are done. 11649d0b21bSJens Axboe */ 11749d0b21bSJens Axboe unlock_page(page); 11849d0b21bSJens Axboe } 11949d0b21bSJens Axboe 120f84d7519SJens Axboe return 0; 12149d0b21bSJens Axboe error: 12249d0b21bSJens Axboe unlock_page(page); 123f84d7519SJens Axboe return err; 12470524490SJens Axboe } 12570524490SJens Axboe 126d4c3cca9SEric Dumazet static const struct pipe_buf_operations page_cache_pipe_buf_ops = { 1275274f052SJens Axboe .can_merge = 0, 128f84d7519SJens Axboe .map = generic_pipe_buf_map, 129f84d7519SJens Axboe .unmap = generic_pipe_buf_unmap, 130f84d7519SJens Axboe .pin = page_cache_pipe_buf_pin, 1315274f052SJens Axboe .release = page_cache_pipe_buf_release, 1325abc97aaSJens Axboe .steal = page_cache_pipe_buf_steal, 133f84d7519SJens Axboe .get = generic_pipe_buf_get, 1345274f052SJens Axboe }; 1355274f052SJens Axboe 136912d35f8SJens Axboe static int user_page_pipe_buf_steal(struct pipe_inode_info *pipe, 137912d35f8SJens Axboe struct pipe_buffer *buf) 138912d35f8SJens Axboe { 1397afa6fd0SJens Axboe if (!(buf->flags & PIPE_BUF_FLAG_GIFT)) 140912d35f8SJens Axboe return 1; 1417afa6fd0SJens Axboe 1421432873aSJens Axboe buf->flags |= PIPE_BUF_FLAG_LRU; 143330ab716SJens Axboe return generic_pipe_buf_steal(pipe, buf); 144912d35f8SJens Axboe } 145912d35f8SJens Axboe 146d4c3cca9SEric Dumazet static const struct pipe_buf_operations user_page_pipe_buf_ops = { 147912d35f8SJens Axboe .can_merge = 0, 148f84d7519SJens Axboe .map = generic_pipe_buf_map, 149f84d7519SJens Axboe .unmap = generic_pipe_buf_unmap, 150f84d7519SJens Axboe .pin = generic_pipe_buf_pin, 151912d35f8SJens Axboe .release = page_cache_pipe_buf_release, 152912d35f8SJens Axboe .steal = user_page_pipe_buf_steal, 153f84d7519SJens Axboe .get = generic_pipe_buf_get, 154912d35f8SJens Axboe }; 155912d35f8SJens Axboe 15683f9135bSJens Axboe /* 157d6b29d7cSJens Axboe * Pipe output worker. This fills a pipe with the information contained 158d6b29d7cSJens Axboe * from splice_pipe_desc(). 15983f9135bSJens Axboe */ 160d6b29d7cSJens Axboe ssize_t splice_to_pipe(struct pipe_inode_info *pipe, 161912d35f8SJens Axboe struct splice_pipe_desc *spd) 1625274f052SJens Axboe { 16300de00bdSJens Axboe unsigned int spd_pages = spd->nr_pages; 164912d35f8SJens Axboe int ret, do_wakeup, page_nr; 1655274f052SJens Axboe 1665274f052SJens Axboe ret = 0; 1675274f052SJens Axboe do_wakeup = 0; 168912d35f8SJens Axboe page_nr = 0; 1695274f052SJens Axboe 1703a326a2cSIngo Molnar if (pipe->inode) 1713a326a2cSIngo Molnar mutex_lock(&pipe->inode->i_mutex); 1725274f052SJens Axboe 1735274f052SJens Axboe for (;;) { 1743a326a2cSIngo Molnar if (!pipe->readers) { 1755274f052SJens Axboe send_sig(SIGPIPE, current, 0); 1765274f052SJens Axboe if (!ret) 1775274f052SJens Axboe ret = -EPIPE; 1785274f052SJens Axboe break; 1795274f052SJens Axboe } 1805274f052SJens Axboe 1816f767b04SJens Axboe if (pipe->nrbufs < PIPE_BUFFERS) { 1826f767b04SJens Axboe int newbuf = (pipe->curbuf + pipe->nrbufs) & (PIPE_BUFFERS - 1); 1833a326a2cSIngo Molnar struct pipe_buffer *buf = pipe->bufs + newbuf; 1845274f052SJens Axboe 185912d35f8SJens Axboe buf->page = spd->pages[page_nr]; 186912d35f8SJens Axboe buf->offset = spd->partial[page_nr].offset; 187912d35f8SJens Axboe buf->len = spd->partial[page_nr].len; 188497f9625SJens Axboe buf->private = spd->partial[page_nr].private; 189912d35f8SJens Axboe buf->ops = spd->ops; 1907afa6fd0SJens Axboe if (spd->flags & SPLICE_F_GIFT) 1917afa6fd0SJens Axboe buf->flags |= PIPE_BUF_FLAG_GIFT; 1927afa6fd0SJens Axboe 1936f767b04SJens Axboe pipe->nrbufs++; 194912d35f8SJens Axboe page_nr++; 195912d35f8SJens Axboe ret += buf->len; 196912d35f8SJens Axboe 1976f767b04SJens Axboe if (pipe->inode) 1985274f052SJens Axboe do_wakeup = 1; 1995274f052SJens Axboe 200912d35f8SJens Axboe if (!--spd->nr_pages) 2015274f052SJens Axboe break; 2026f767b04SJens Axboe if (pipe->nrbufs < PIPE_BUFFERS) 2035274f052SJens Axboe continue; 2045274f052SJens Axboe 2055274f052SJens Axboe break; 2065274f052SJens Axboe } 2075274f052SJens Axboe 208912d35f8SJens Axboe if (spd->flags & SPLICE_F_NONBLOCK) { 20929e35094SLinus Torvalds if (!ret) 21029e35094SLinus Torvalds ret = -EAGAIN; 21129e35094SLinus Torvalds break; 21229e35094SLinus Torvalds } 21329e35094SLinus Torvalds 2145274f052SJens Axboe if (signal_pending(current)) { 2155274f052SJens Axboe if (!ret) 2165274f052SJens Axboe ret = -ERESTARTSYS; 2175274f052SJens Axboe break; 2185274f052SJens Axboe } 2195274f052SJens Axboe 2205274f052SJens Axboe if (do_wakeup) { 221c0bd1f65SJens Axboe smp_mb(); 2223a326a2cSIngo Molnar if (waitqueue_active(&pipe->wait)) 2233a326a2cSIngo Molnar wake_up_interruptible_sync(&pipe->wait); 2243a326a2cSIngo Molnar kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN); 2255274f052SJens Axboe do_wakeup = 0; 2265274f052SJens Axboe } 2275274f052SJens Axboe 2283a326a2cSIngo Molnar pipe->waiting_writers++; 2293a326a2cSIngo Molnar pipe_wait(pipe); 2303a326a2cSIngo Molnar pipe->waiting_writers--; 2315274f052SJens Axboe } 2325274f052SJens Axboe 23302676e5aSJens Axboe if (pipe->inode) { 2343a326a2cSIngo Molnar mutex_unlock(&pipe->inode->i_mutex); 2355274f052SJens Axboe 2365274f052SJens Axboe if (do_wakeup) { 237c0bd1f65SJens Axboe smp_mb(); 2383a326a2cSIngo Molnar if (waitqueue_active(&pipe->wait)) 2393a326a2cSIngo Molnar wake_up_interruptible(&pipe->wait); 2403a326a2cSIngo Molnar kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN); 2415274f052SJens Axboe } 24202676e5aSJens Axboe } 2435274f052SJens Axboe 24400de00bdSJens Axboe while (page_nr < spd_pages) 245912d35f8SJens Axboe page_cache_release(spd->pages[page_nr++]); 2465274f052SJens Axboe 2475274f052SJens Axboe return ret; 2485274f052SJens Axboe } 2495274f052SJens Axboe 2503a326a2cSIngo Molnar static int 251cbb7e577SJens Axboe __generic_file_splice_read(struct file *in, loff_t *ppos, 252cbb7e577SJens Axboe struct pipe_inode_info *pipe, size_t len, 253cbb7e577SJens Axboe unsigned int flags) 2545274f052SJens Axboe { 2555274f052SJens Axboe struct address_space *mapping = in->f_mapping; 256912d35f8SJens Axboe unsigned int loff, nr_pages; 25716c523ddSJens Axboe struct page *pages[PIPE_BUFFERS]; 258912d35f8SJens Axboe struct partial_page partial[PIPE_BUFFERS]; 2595274f052SJens Axboe struct page *page; 26091ad66efSJens Axboe pgoff_t index, end_index; 26191ad66efSJens Axboe loff_t isize; 262eb20796bSJens Axboe int error, page_nr; 263912d35f8SJens Axboe struct splice_pipe_desc spd = { 264912d35f8SJens Axboe .pages = pages, 265912d35f8SJens Axboe .partial = partial, 266912d35f8SJens Axboe .flags = flags, 267912d35f8SJens Axboe .ops = &page_cache_pipe_buf_ops, 268912d35f8SJens Axboe }; 2695274f052SJens Axboe 270cbb7e577SJens Axboe index = *ppos >> PAGE_CACHE_SHIFT; 271912d35f8SJens Axboe loff = *ppos & ~PAGE_CACHE_MASK; 272912d35f8SJens Axboe nr_pages = (len + loff + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; 2735274f052SJens Axboe 2745274f052SJens Axboe if (nr_pages > PIPE_BUFFERS) 2755274f052SJens Axboe nr_pages = PIPE_BUFFERS; 2765274f052SJens Axboe 2775274f052SJens Axboe /* 27886aa5ac5SJens Axboe * Don't try to 2nd guess the read-ahead logic, call into 27986aa5ac5SJens Axboe * page_cache_readahead() like the page cache reads would do. 2805274f052SJens Axboe */ 281eb645a24SJens Axboe page_cache_readahead(mapping, &in->f_ra, in, index, nr_pages); 2825274f052SJens Axboe 2835274f052SJens Axboe /* 28473d62d83SIngo Molnar * Now fill in the holes: 2855274f052SJens Axboe */ 2867480a904SJens Axboe error = 0; 28782aa5d61SJens Axboe 28882aa5d61SJens Axboe /* 289eb20796bSJens Axboe * Lookup the (hopefully) full range of pages we need. 29082aa5d61SJens Axboe */ 291eb20796bSJens Axboe spd.nr_pages = find_get_pages_contig(mapping, index, nr_pages, pages); 292eb20796bSJens Axboe 2935274f052SJens Axboe /* 294eb20796bSJens Axboe * If find_get_pages_contig() returned fewer pages than we needed, 295eb20796bSJens Axboe * allocate the rest. 296eb20796bSJens Axboe */ 297eb20796bSJens Axboe index += spd.nr_pages; 298eb20796bSJens Axboe while (spd.nr_pages < nr_pages) { 299eb20796bSJens Axboe /* 300eb20796bSJens Axboe * Page could be there, find_get_pages_contig() breaks on 301eb20796bSJens Axboe * the first hole. 3025274f052SJens Axboe */ 3037480a904SJens Axboe page = find_get_page(mapping, index); 3047480a904SJens Axboe if (!page) { 3057480a904SJens Axboe /* 306e27dedd8SJens Axboe * Make sure the read-ahead engine is notified 307e27dedd8SJens Axboe * about this failure. 308e27dedd8SJens Axboe */ 309e27dedd8SJens Axboe handle_ra_miss(mapping, &in->f_ra, index); 310e27dedd8SJens Axboe 311e27dedd8SJens Axboe /* 312eb20796bSJens Axboe * page didn't exist, allocate one. 3137480a904SJens Axboe */ 3147480a904SJens Axboe page = page_cache_alloc_cold(mapping); 3155274f052SJens Axboe if (!page) 3165274f052SJens Axboe break; 3175274f052SJens Axboe 3187480a904SJens Axboe error = add_to_page_cache_lru(page, mapping, index, 3192ae88149SNick Piggin GFP_KERNEL); 3205274f052SJens Axboe if (unlikely(error)) { 3215274f052SJens Axboe page_cache_release(page); 322a0548871SJens Axboe if (error == -EEXIST) 323a0548871SJens Axboe continue; 3245274f052SJens Axboe break; 3255274f052SJens Axboe } 326eb20796bSJens Axboe /* 327eb20796bSJens Axboe * add_to_page_cache() locks the page, unlock it 328eb20796bSJens Axboe * to avoid convoluting the logic below even more. 329eb20796bSJens Axboe */ 330eb20796bSJens Axboe unlock_page(page); 3315274f052SJens Axboe } 3327480a904SJens Axboe 333eb20796bSJens Axboe pages[spd.nr_pages++] = page; 334eb20796bSJens Axboe index++; 335eb20796bSJens Axboe } 336eb20796bSJens Axboe 337eb20796bSJens Axboe /* 338eb20796bSJens Axboe * Now loop over the map and see if we need to start IO on any 339eb20796bSJens Axboe * pages, fill in the partial map, etc. 340eb20796bSJens Axboe */ 341eb20796bSJens Axboe index = *ppos >> PAGE_CACHE_SHIFT; 342eb20796bSJens Axboe nr_pages = spd.nr_pages; 343eb20796bSJens Axboe spd.nr_pages = 0; 344eb20796bSJens Axboe for (page_nr = 0; page_nr < nr_pages; page_nr++) { 345eb20796bSJens Axboe unsigned int this_len; 346eb20796bSJens Axboe 347eb20796bSJens Axboe if (!len) 348eb20796bSJens Axboe break; 349eb20796bSJens Axboe 350eb20796bSJens Axboe /* 351eb20796bSJens Axboe * this_len is the max we'll use from this page 352eb20796bSJens Axboe */ 353eb20796bSJens Axboe this_len = min_t(unsigned long, len, PAGE_CACHE_SIZE - loff); 354eb20796bSJens Axboe page = pages[page_nr]; 355eb20796bSJens Axboe 3567480a904SJens Axboe /* 3577480a904SJens Axboe * If the page isn't uptodate, we may need to start io on it 3587480a904SJens Axboe */ 3597480a904SJens Axboe if (!PageUptodate(page)) { 360c4f895cbSJens Axboe /* 361c4f895cbSJens Axboe * If in nonblock mode then dont block on waiting 362c4f895cbSJens Axboe * for an in-flight io page 363c4f895cbSJens Axboe */ 3649ae9d68cSFengguang Wu if (flags & SPLICE_F_NONBLOCK) { 3659ae9d68cSFengguang Wu if (TestSetPageLocked(page)) 366c4f895cbSJens Axboe break; 3679ae9d68cSFengguang Wu } else 3687480a904SJens Axboe lock_page(page); 3697480a904SJens Axboe 3707480a904SJens Axboe /* 3717480a904SJens Axboe * page was truncated, stop here. if this isn't the 3727480a904SJens Axboe * first page, we'll just complete what we already 3737480a904SJens Axboe * added 3747480a904SJens Axboe */ 3757480a904SJens Axboe if (!page->mapping) { 3767480a904SJens Axboe unlock_page(page); 3777480a904SJens Axboe break; 3787480a904SJens Axboe } 3797480a904SJens Axboe /* 3807480a904SJens Axboe * page was already under io and is now done, great 3817480a904SJens Axboe */ 3827480a904SJens Axboe if (PageUptodate(page)) { 3837480a904SJens Axboe unlock_page(page); 3847480a904SJens Axboe goto fill_it; 3857480a904SJens Axboe } 3867480a904SJens Axboe 3877480a904SJens Axboe /* 3887480a904SJens Axboe * need to read in the page 3897480a904SJens Axboe */ 3907480a904SJens Axboe error = mapping->a_ops->readpage(in, page); 3917480a904SJens Axboe if (unlikely(error)) { 392eb20796bSJens Axboe /* 393eb20796bSJens Axboe * We really should re-lookup the page here, 394eb20796bSJens Axboe * but it complicates things a lot. Instead 395eb20796bSJens Axboe * lets just do what we already stored, and 396eb20796bSJens Axboe * we'll get it the next time we are called. 397eb20796bSJens Axboe */ 3987480a904SJens Axboe if (error == AOP_TRUNCATED_PAGE) 399eb20796bSJens Axboe error = 0; 400eb20796bSJens Axboe 4017480a904SJens Axboe break; 4027480a904SJens Axboe } 403620a324bSJens Axboe } 404620a324bSJens Axboe fill_it: 40591ad66efSJens Axboe /* 406620a324bSJens Axboe * i_size must be checked after PageUptodate. 40791ad66efSJens Axboe */ 40891ad66efSJens Axboe isize = i_size_read(mapping->host); 40991ad66efSJens Axboe end_index = (isize - 1) >> PAGE_CACHE_SHIFT; 410eb20796bSJens Axboe if (unlikely(!isize || index > end_index)) 41191ad66efSJens Axboe break; 41291ad66efSJens Axboe 41391ad66efSJens Axboe /* 41491ad66efSJens Axboe * if this is the last page, see if we need to shrink 41591ad66efSJens Axboe * the length and stop 41691ad66efSJens Axboe */ 41791ad66efSJens Axboe if (end_index == index) { 418475ecadeSHugh Dickins unsigned int plen; 419475ecadeSHugh Dickins 420475ecadeSHugh Dickins /* 421475ecadeSHugh Dickins * max good bytes in this page 422475ecadeSHugh Dickins */ 423475ecadeSHugh Dickins plen = ((isize - 1) & ~PAGE_CACHE_MASK) + 1; 424475ecadeSHugh Dickins if (plen <= loff) 42591ad66efSJens Axboe break; 426475ecadeSHugh Dickins 42791ad66efSJens Axboe /* 42891ad66efSJens Axboe * force quit after adding this page 42991ad66efSJens Axboe */ 430475ecadeSHugh Dickins this_len = min(this_len, plen - loff); 431eb20796bSJens Axboe len = this_len; 43291ad66efSJens Axboe } 433620a324bSJens Axboe 434eb20796bSJens Axboe partial[page_nr].offset = loff; 435eb20796bSJens Axboe partial[page_nr].len = this_len; 43682aa5d61SJens Axboe len -= this_len; 43791ad66efSJens Axboe loff = 0; 438eb20796bSJens Axboe spd.nr_pages++; 439eb20796bSJens Axboe index++; 4405274f052SJens Axboe } 4415274f052SJens Axboe 442eb20796bSJens Axboe /* 443475ecadeSHugh Dickins * Release any pages at the end, if we quit early. 'page_nr' is how far 444eb20796bSJens Axboe * we got, 'nr_pages' is how many pages are in the map. 445eb20796bSJens Axboe */ 446eb20796bSJens Axboe while (page_nr < nr_pages) 447eb20796bSJens Axboe page_cache_release(pages[page_nr++]); 448eb20796bSJens Axboe 449912d35f8SJens Axboe if (spd.nr_pages) 45000522fb4SJens Axboe return splice_to_pipe(pipe, &spd); 45116c523ddSJens Axboe 4527480a904SJens Axboe return error; 4535274f052SJens Axboe } 4545274f052SJens Axboe 45583f9135bSJens Axboe /** 45683f9135bSJens Axboe * generic_file_splice_read - splice data from file to a pipe 45783f9135bSJens Axboe * @in: file to splice from 45883f9135bSJens Axboe * @pipe: pipe to splice to 45983f9135bSJens Axboe * @len: number of bytes to splice 46083f9135bSJens Axboe * @flags: splice modifier flags 46183f9135bSJens Axboe * 46283f9135bSJens Axboe * Will read pages from given file and fill them into a pipe. 46383f9135bSJens Axboe */ 464cbb7e577SJens Axboe ssize_t generic_file_splice_read(struct file *in, loff_t *ppos, 465cbb7e577SJens Axboe struct pipe_inode_info *pipe, size_t len, 466cbb7e577SJens Axboe unsigned int flags) 4675274f052SJens Axboe { 4685274f052SJens Axboe ssize_t spliced; 4695274f052SJens Axboe int ret; 470d366d398SJens Axboe loff_t isize, left; 471d366d398SJens Axboe 472d366d398SJens Axboe isize = i_size_read(in->f_mapping->host); 473d366d398SJens Axboe if (unlikely(*ppos >= isize)) 474d366d398SJens Axboe return 0; 475d366d398SJens Axboe 476d366d398SJens Axboe left = isize - *ppos; 477d366d398SJens Axboe if (unlikely(left < len)) 478d366d398SJens Axboe len = left; 4795274f052SJens Axboe 4805274f052SJens Axboe ret = 0; 4815274f052SJens Axboe spliced = 0; 4825274f052SJens Axboe while (len) { 483cbb7e577SJens Axboe ret = __generic_file_splice_read(in, ppos, pipe, len, flags); 4845274f052SJens Axboe 485c4f895cbSJens Axboe if (ret < 0) 4865274f052SJens Axboe break; 487c4f895cbSJens Axboe else if (!ret) { 488c4f895cbSJens Axboe if (spliced) 489c4f895cbSJens Axboe break; 490c4f895cbSJens Axboe if (flags & SPLICE_F_NONBLOCK) { 491c4f895cbSJens Axboe ret = -EAGAIN; 492c4f895cbSJens Axboe break; 493c4f895cbSJens Axboe } 494c4f895cbSJens Axboe } 4955274f052SJens Axboe 496cbb7e577SJens Axboe *ppos += ret; 4975274f052SJens Axboe len -= ret; 4985274f052SJens Axboe spliced += ret; 4995274f052SJens Axboe } 5005274f052SJens Axboe 5015274f052SJens Axboe if (spliced) 5025274f052SJens Axboe return spliced; 5035274f052SJens Axboe 5045274f052SJens Axboe return ret; 5055274f052SJens Axboe } 5065274f052SJens Axboe 507059a8f37SJens Axboe EXPORT_SYMBOL(generic_file_splice_read); 508059a8f37SJens Axboe 5095274f052SJens Axboe /* 5104f6f0bd2SJens Axboe * Send 'sd->len' bytes to socket from 'sd->file' at position 'sd->pos' 511016b661eSJens Axboe * using sendpage(). Return the number of bytes sent. 5125274f052SJens Axboe */ 51376ad4d11SJens Axboe static int pipe_to_sendpage(struct pipe_inode_info *pipe, 5145274f052SJens Axboe struct pipe_buffer *buf, struct splice_desc *sd) 5155274f052SJens Axboe { 5166a14b90bSJens Axboe struct file *file = sd->u.file; 5175274f052SJens Axboe loff_t pos = sd->pos; 518f84d7519SJens Axboe int ret, more; 5195274f052SJens Axboe 52076ad4d11SJens Axboe ret = buf->ops->pin(pipe, buf); 521f84d7519SJens Axboe if (!ret) { 522b2b39fa4SJens Axboe more = (sd->flags & SPLICE_F_MORE) || sd->len < sd->total_len; 5235274f052SJens Axboe 524f84d7519SJens Axboe ret = file->f_op->sendpage(file, buf->page, buf->offset, 525f84d7519SJens Axboe sd->len, &pos, more); 526f84d7519SJens Axboe } 5275274f052SJens Axboe 528016b661eSJens Axboe return ret; 5295274f052SJens Axboe } 5305274f052SJens Axboe 5315274f052SJens Axboe /* 5325274f052SJens Axboe * This is a little more tricky than the file -> pipe splicing. There are 5335274f052SJens Axboe * basically three cases: 5345274f052SJens Axboe * 5355274f052SJens Axboe * - Destination page already exists in the address space and there 5365274f052SJens Axboe * are users of it. For that case we have no other option that 5375274f052SJens Axboe * copying the data. Tough luck. 5385274f052SJens Axboe * - Destination page already exists in the address space, but there 5395274f052SJens Axboe * are no users of it. Make sure it's uptodate, then drop it. Fall 5405274f052SJens Axboe * through to last case. 5415274f052SJens Axboe * - Destination page does not exist, we can add the pipe page to 5425274f052SJens Axboe * the page cache and avoid the copy. 5435274f052SJens Axboe * 54483f9135bSJens Axboe * If asked to move pages to the output file (SPLICE_F_MOVE is set in 54583f9135bSJens Axboe * sd->flags), we attempt to migrate pages from the pipe to the output 54683f9135bSJens Axboe * file address space page cache. This is possible if no one else has 54783f9135bSJens Axboe * the pipe page referenced outside of the pipe and page cache. If 54883f9135bSJens Axboe * SPLICE_F_MOVE isn't set, or we cannot move the page, we simply create 54983f9135bSJens Axboe * a new page in the output file page cache and fill/dirty that. 5505274f052SJens Axboe */ 55176ad4d11SJens Axboe static int pipe_to_file(struct pipe_inode_info *pipe, struct pipe_buffer *buf, 5525274f052SJens Axboe struct splice_desc *sd) 5535274f052SJens Axboe { 5546a14b90bSJens Axboe struct file *file = sd->u.file; 5555274f052SJens Axboe struct address_space *mapping = file->f_mapping; 556016b661eSJens Axboe unsigned int offset, this_len; 5575274f052SJens Axboe struct page *page; 5585274f052SJens Axboe pgoff_t index; 5593e7ee3e7SJens Axboe int ret; 5605274f052SJens Axboe 5615274f052SJens Axboe /* 56249d0b21bSJens Axboe * make sure the data in this buffer is uptodate 5635274f052SJens Axboe */ 56476ad4d11SJens Axboe ret = buf->ops->pin(pipe, buf); 565f84d7519SJens Axboe if (unlikely(ret)) 566f84d7519SJens Axboe return ret; 5675274f052SJens Axboe 5685274f052SJens Axboe index = sd->pos >> PAGE_CACHE_SHIFT; 5695274f052SJens Axboe offset = sd->pos & ~PAGE_CACHE_MASK; 5705274f052SJens Axboe 571016b661eSJens Axboe this_len = sd->len; 572016b661eSJens Axboe if (this_len + offset > PAGE_CACHE_SIZE) 573016b661eSJens Axboe this_len = PAGE_CACHE_SIZE - offset; 574016b661eSJens Axboe 5755274f052SJens Axboe find_page: 5769e0267c2SJens Axboe page = find_lock_page(mapping, index); 5779e0267c2SJens Axboe if (!page) { 5785274f052SJens Axboe ret = -ENOMEM; 5799e0267c2SJens Axboe page = page_cache_alloc_cold(mapping); 5809e0267c2SJens Axboe if (unlikely(!page)) 581e6e80f29SJens Axboe goto out_ret; 5825274f052SJens Axboe 5835274f052SJens Axboe /* 5849e0267c2SJens Axboe * This will also lock the page 5859e0267c2SJens Axboe */ 5869e0267c2SJens Axboe ret = add_to_page_cache_lru(page, mapping, index, 5872ae88149SNick Piggin GFP_KERNEL); 5889e0267c2SJens Axboe if (unlikely(ret)) 5899e0267c2SJens Axboe goto out; 5909e0267c2SJens Axboe } 5919e0267c2SJens Axboe 592016b661eSJens Axboe ret = mapping->a_ops->prepare_write(file, page, offset, offset+this_len); 593bfc4ee39SJens Axboe if (unlikely(ret)) { 594bfc4ee39SJens Axboe loff_t isize = i_size_read(mapping->host); 595bfc4ee39SJens Axboe 596bfc4ee39SJens Axboe if (ret != AOP_TRUNCATED_PAGE) 597bfc4ee39SJens Axboe unlock_page(page); 5984f6f0bd2SJens Axboe page_cache_release(page); 599bfc4ee39SJens Axboe if (ret == AOP_TRUNCATED_PAGE) 6004f6f0bd2SJens Axboe goto find_page; 601bfc4ee39SJens Axboe 602bfc4ee39SJens Axboe /* 603bfc4ee39SJens Axboe * prepare_write() may have instantiated a few blocks 604bfc4ee39SJens Axboe * outside i_size. Trim these off again. 605bfc4ee39SJens Axboe */ 606bfc4ee39SJens Axboe if (sd->pos + this_len > isize) 607bfc4ee39SJens Axboe vmtruncate(mapping->host, isize); 608bfc4ee39SJens Axboe 609e6e80f29SJens Axboe goto out_ret; 610bfc4ee39SJens Axboe } 6115274f052SJens Axboe 6120568b409SJens Axboe if (buf->page != page) { 613f84d7519SJens Axboe /* 614f84d7519SJens Axboe * Careful, ->map() uses KM_USER0! 615f84d7519SJens Axboe */ 61676ad4d11SJens Axboe char *src = buf->ops->map(pipe, buf, 1); 617f84d7519SJens Axboe char *dst = kmap_atomic(page, KM_USER1); 6185abc97aaSJens Axboe 619016b661eSJens Axboe memcpy(dst + offset, src + buf->offset, this_len); 6205274f052SJens Axboe flush_dcache_page(page); 621f84d7519SJens Axboe kunmap_atomic(dst, KM_USER1); 62276ad4d11SJens Axboe buf->ops->unmap(pipe, buf, src); 6235abc97aaSJens Axboe } 6245274f052SJens Axboe 625016b661eSJens Axboe ret = mapping->a_ops->commit_write(file, page, offset, offset+this_len); 626d9993c37SDmitriy Monakhov if (ret) { 627d9993c37SDmitriy Monakhov if (ret == AOP_TRUNCATED_PAGE) { 628d9993c37SDmitriy Monakhov page_cache_release(page); 629d9993c37SDmitriy Monakhov goto find_page; 630d9993c37SDmitriy Monakhov } 631d9993c37SDmitriy Monakhov if (ret < 0) 632d9993c37SDmitriy Monakhov goto out; 633d9993c37SDmitriy Monakhov /* 634d9993c37SDmitriy Monakhov * Partial write has happened, so 'ret' already initialized by 635d9993c37SDmitriy Monakhov * number of bytes written, Where is nothing we have to do here. 636d9993c37SDmitriy Monakhov */ 637d9993c37SDmitriy Monakhov } else 638d9993c37SDmitriy Monakhov ret = this_len; 639016b661eSJens Axboe /* 6400568b409SJens Axboe * Return the number of bytes written and mark page as 6410568b409SJens Axboe * accessed, we are now done! 642016b661eSJens Axboe */ 643c7f21e4fSJens Axboe mark_page_accessed(page); 6440568b409SJens Axboe out: 6450568b409SJens Axboe page_cache_release(page); 6464f6f0bd2SJens Axboe unlock_page(page); 647e6e80f29SJens Axboe out_ret: 6485274f052SJens Axboe return ret; 6495274f052SJens Axboe } 6505274f052SJens Axboe 65183f9135bSJens Axboe /* 65283f9135bSJens Axboe * Pipe input worker. Most of this logic works like a regular pipe, the 65383f9135bSJens Axboe * key here is the 'actor' worker passed in that actually moves the data 65483f9135bSJens Axboe * to the wanted destination. See pipe_to_file/pipe_to_sendpage above. 65583f9135bSJens Axboe */ 656c66ab6faSJens Axboe ssize_t __splice_from_pipe(struct pipe_inode_info *pipe, struct splice_desc *sd, 657c66ab6faSJens Axboe splice_actor *actor) 6585274f052SJens Axboe { 6595274f052SJens Axboe int ret, do_wakeup, err; 6605274f052SJens Axboe 6615274f052SJens Axboe ret = 0; 6625274f052SJens Axboe do_wakeup = 0; 6635274f052SJens Axboe 6645274f052SJens Axboe for (;;) { 6656f767b04SJens Axboe if (pipe->nrbufs) { 6666f767b04SJens Axboe struct pipe_buffer *buf = pipe->bufs + pipe->curbuf; 667d4c3cca9SEric Dumazet const struct pipe_buf_operations *ops = buf->ops; 6685274f052SJens Axboe 669c66ab6faSJens Axboe sd->len = buf->len; 670c66ab6faSJens Axboe if (sd->len > sd->total_len) 671c66ab6faSJens Axboe sd->len = sd->total_len; 6725274f052SJens Axboe 673c66ab6faSJens Axboe err = actor(pipe, buf, sd); 674016b661eSJens Axboe if (err <= 0) { 6755274f052SJens Axboe if (!ret && err != -ENODATA) 6765274f052SJens Axboe ret = err; 6775274f052SJens Axboe 6785274f052SJens Axboe break; 6795274f052SJens Axboe } 6805274f052SJens Axboe 681016b661eSJens Axboe ret += err; 682016b661eSJens Axboe buf->offset += err; 683016b661eSJens Axboe buf->len -= err; 684016b661eSJens Axboe 685c66ab6faSJens Axboe sd->len -= err; 686c66ab6faSJens Axboe sd->pos += err; 687c66ab6faSJens Axboe sd->total_len -= err; 688c66ab6faSJens Axboe if (sd->len) 689016b661eSJens Axboe continue; 69073d62d83SIngo Molnar 6915274f052SJens Axboe if (!buf->len) { 6925274f052SJens Axboe buf->ops = NULL; 6933a326a2cSIngo Molnar ops->release(pipe, buf); 6946f767b04SJens Axboe pipe->curbuf = (pipe->curbuf + 1) & (PIPE_BUFFERS - 1); 6956f767b04SJens Axboe pipe->nrbufs--; 6966f767b04SJens Axboe if (pipe->inode) 6975274f052SJens Axboe do_wakeup = 1; 6985274f052SJens Axboe } 6995274f052SJens Axboe 700c66ab6faSJens Axboe if (!sd->total_len) 7015274f052SJens Axboe break; 7025274f052SJens Axboe } 7035274f052SJens Axboe 7046f767b04SJens Axboe if (pipe->nrbufs) 7055274f052SJens Axboe continue; 7063a326a2cSIngo Molnar if (!pipe->writers) 7075274f052SJens Axboe break; 7083a326a2cSIngo Molnar if (!pipe->waiting_writers) { 7095274f052SJens Axboe if (ret) 7105274f052SJens Axboe break; 7115274f052SJens Axboe } 7125274f052SJens Axboe 713c66ab6faSJens Axboe if (sd->flags & SPLICE_F_NONBLOCK) { 71429e35094SLinus Torvalds if (!ret) 71529e35094SLinus Torvalds ret = -EAGAIN; 71629e35094SLinus Torvalds break; 71729e35094SLinus Torvalds } 71829e35094SLinus Torvalds 7195274f052SJens Axboe if (signal_pending(current)) { 7205274f052SJens Axboe if (!ret) 7215274f052SJens Axboe ret = -ERESTARTSYS; 7225274f052SJens Axboe break; 7235274f052SJens Axboe } 7245274f052SJens Axboe 7255274f052SJens Axboe if (do_wakeup) { 726c0bd1f65SJens Axboe smp_mb(); 7273a326a2cSIngo Molnar if (waitqueue_active(&pipe->wait)) 7283a326a2cSIngo Molnar wake_up_interruptible_sync(&pipe->wait); 7293a326a2cSIngo Molnar kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT); 7305274f052SJens Axboe do_wakeup = 0; 7315274f052SJens Axboe } 7325274f052SJens Axboe 7333a326a2cSIngo Molnar pipe_wait(pipe); 7345274f052SJens Axboe } 7355274f052SJens Axboe 7365274f052SJens Axboe if (do_wakeup) { 737c0bd1f65SJens Axboe smp_mb(); 7383a326a2cSIngo Molnar if (waitqueue_active(&pipe->wait)) 7393a326a2cSIngo Molnar wake_up_interruptible(&pipe->wait); 7403a326a2cSIngo Molnar kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT); 7415274f052SJens Axboe } 7425274f052SJens Axboe 7435274f052SJens Axboe return ret; 7445274f052SJens Axboe } 74540bee44eSMark Fasheh EXPORT_SYMBOL(__splice_from_pipe); 7465274f052SJens Axboe 7476da61809SMark Fasheh ssize_t splice_from_pipe(struct pipe_inode_info *pipe, struct file *out, 7486da61809SMark Fasheh loff_t *ppos, size_t len, unsigned int flags, 7496da61809SMark Fasheh splice_actor *actor) 7506da61809SMark Fasheh { 7516da61809SMark Fasheh ssize_t ret; 7526da61809SMark Fasheh struct inode *inode = out->f_mapping->host; 753c66ab6faSJens Axboe struct splice_desc sd = { 754c66ab6faSJens Axboe .total_len = len, 755c66ab6faSJens Axboe .flags = flags, 756c66ab6faSJens Axboe .pos = *ppos, 7576a14b90bSJens Axboe .u.file = out, 758c66ab6faSJens Axboe }; 7596da61809SMark Fasheh 7606da61809SMark Fasheh /* 7616da61809SMark Fasheh * The actor worker might be calling ->prepare_write and 7626da61809SMark Fasheh * ->commit_write. Most of the time, these expect i_mutex to 7636da61809SMark Fasheh * be held. Since this may result in an ABBA deadlock with 7646da61809SMark Fasheh * pipe->inode, we have to order lock acquiry here. 7656da61809SMark Fasheh */ 7666da61809SMark Fasheh inode_double_lock(inode, pipe->inode); 767c66ab6faSJens Axboe ret = __splice_from_pipe(pipe, &sd, actor); 7686da61809SMark Fasheh inode_double_unlock(inode, pipe->inode); 7696da61809SMark Fasheh 7706da61809SMark Fasheh return ret; 7716da61809SMark Fasheh } 7726da61809SMark Fasheh 7736da61809SMark Fasheh /** 7746da61809SMark Fasheh * generic_file_splice_write_nolock - generic_file_splice_write without mutexes 7756da61809SMark Fasheh * @pipe: pipe info 7766da61809SMark Fasheh * @out: file to write to 7776da61809SMark Fasheh * @len: number of bytes to splice 7786da61809SMark Fasheh * @flags: splice modifier flags 7796da61809SMark Fasheh * 7806da61809SMark Fasheh * Will either move or copy pages (determined by @flags options) from 7816da61809SMark Fasheh * the given pipe inode to the given file. The caller is responsible 7826da61809SMark Fasheh * for acquiring i_mutex on both inodes. 7836da61809SMark Fasheh * 7846da61809SMark Fasheh */ 7856da61809SMark Fasheh ssize_t 7866da61809SMark Fasheh generic_file_splice_write_nolock(struct pipe_inode_info *pipe, struct file *out, 7876da61809SMark Fasheh loff_t *ppos, size_t len, unsigned int flags) 7886da61809SMark Fasheh { 7896da61809SMark Fasheh struct address_space *mapping = out->f_mapping; 7906da61809SMark Fasheh struct inode *inode = mapping->host; 791c66ab6faSJens Axboe struct splice_desc sd = { 792c66ab6faSJens Axboe .total_len = len, 793c66ab6faSJens Axboe .flags = flags, 794c66ab6faSJens Axboe .pos = *ppos, 7956a14b90bSJens Axboe .u.file = out, 796c66ab6faSJens Axboe }; 7976da61809SMark Fasheh ssize_t ret; 7986da61809SMark Fasheh int err; 7996da61809SMark Fasheh 8000f7fc9e4SJosef "Jeff" Sipek err = remove_suid(out->f_path.dentry); 8018c34e2d6SJens Axboe if (unlikely(err)) 8028c34e2d6SJens Axboe return err; 8038c34e2d6SJens Axboe 804c66ab6faSJens Axboe ret = __splice_from_pipe(pipe, &sd, pipe_to_file); 8056da61809SMark Fasheh if (ret > 0) { 80617ee4f49SJens Axboe unsigned long nr_pages; 80717ee4f49SJens Axboe 8086da61809SMark Fasheh *ppos += ret; 80917ee4f49SJens Axboe nr_pages = (ret + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; 8106da61809SMark Fasheh 8116da61809SMark Fasheh /* 8126da61809SMark Fasheh * If file or inode is SYNC and we actually wrote some data, 8136da61809SMark Fasheh * sync it. 8146da61809SMark Fasheh */ 8156da61809SMark Fasheh if (unlikely((out->f_flags & O_SYNC) || IS_SYNC(inode))) { 8166da61809SMark Fasheh err = generic_osync_inode(inode, mapping, 8176da61809SMark Fasheh OSYNC_METADATA|OSYNC_DATA); 8186da61809SMark Fasheh 8196da61809SMark Fasheh if (err) 8206da61809SMark Fasheh ret = err; 8216da61809SMark Fasheh } 82217ee4f49SJens Axboe balance_dirty_pages_ratelimited_nr(mapping, nr_pages); 8236da61809SMark Fasheh } 8246da61809SMark Fasheh 8256da61809SMark Fasheh return ret; 8266da61809SMark Fasheh } 8276da61809SMark Fasheh 8286da61809SMark Fasheh EXPORT_SYMBOL(generic_file_splice_write_nolock); 8296da61809SMark Fasheh 83083f9135bSJens Axboe /** 83183f9135bSJens Axboe * generic_file_splice_write - splice data from a pipe to a file 8323a326a2cSIngo Molnar * @pipe: pipe info 83383f9135bSJens Axboe * @out: file to write to 83483f9135bSJens Axboe * @len: number of bytes to splice 83583f9135bSJens Axboe * @flags: splice modifier flags 83683f9135bSJens Axboe * 83783f9135bSJens Axboe * Will either move or copy pages (determined by @flags options) from 83883f9135bSJens Axboe * the given pipe inode to the given file. 83983f9135bSJens Axboe * 84083f9135bSJens Axboe */ 8413a326a2cSIngo Molnar ssize_t 8423a326a2cSIngo Molnar generic_file_splice_write(struct pipe_inode_info *pipe, struct file *out, 843cbb7e577SJens Axboe loff_t *ppos, size_t len, unsigned int flags) 8445274f052SJens Axboe { 8454f6f0bd2SJens Axboe struct address_space *mapping = out->f_mapping; 8468c34e2d6SJens Axboe struct inode *inode = mapping->host; 8473a326a2cSIngo Molnar ssize_t ret; 8488c34e2d6SJens Axboe int err; 8498c34e2d6SJens Axboe 8500f7fc9e4SJosef "Jeff" Sipek err = should_remove_suid(out->f_path.dentry); 8518c34e2d6SJens Axboe if (unlikely(err)) { 8528c34e2d6SJens Axboe mutex_lock(&inode->i_mutex); 8530f7fc9e4SJosef "Jeff" Sipek err = __remove_suid(out->f_path.dentry, err); 8548c34e2d6SJens Axboe mutex_unlock(&inode->i_mutex); 8558c34e2d6SJens Axboe if (err) 8568c34e2d6SJens Axboe return err; 8578c34e2d6SJens Axboe } 8583a326a2cSIngo Molnar 85900522fb4SJens Axboe ret = splice_from_pipe(pipe, out, ppos, len, flags, pipe_to_file); 860a4514ebdSJens Axboe if (ret > 0) { 86117ee4f49SJens Axboe unsigned long nr_pages; 86217ee4f49SJens Axboe 863a4514ebdSJens Axboe *ppos += ret; 86417ee4f49SJens Axboe nr_pages = (ret + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; 8654f6f0bd2SJens Axboe 8664f6f0bd2SJens Axboe /* 867a4514ebdSJens Axboe * If file or inode is SYNC and we actually wrote some data, 868a4514ebdSJens Axboe * sync it. 8694f6f0bd2SJens Axboe */ 870a4514ebdSJens Axboe if (unlikely((out->f_flags & O_SYNC) || IS_SYNC(inode))) { 8714f6f0bd2SJens Axboe mutex_lock(&inode->i_mutex); 872a4514ebdSJens Axboe err = generic_osync_inode(inode, mapping, 8734f6f0bd2SJens Axboe OSYNC_METADATA|OSYNC_DATA); 8744f6f0bd2SJens Axboe mutex_unlock(&inode->i_mutex); 8754f6f0bd2SJens Axboe 8764f6f0bd2SJens Axboe if (err) 8774f6f0bd2SJens Axboe ret = err; 8784f6f0bd2SJens Axboe } 87917ee4f49SJens Axboe balance_dirty_pages_ratelimited_nr(mapping, nr_pages); 880a4514ebdSJens Axboe } 8814f6f0bd2SJens Axboe 8824f6f0bd2SJens Axboe return ret; 8835274f052SJens Axboe } 8845274f052SJens Axboe 885059a8f37SJens Axboe EXPORT_SYMBOL(generic_file_splice_write); 886059a8f37SJens Axboe 88783f9135bSJens Axboe /** 88883f9135bSJens Axboe * generic_splice_sendpage - splice data from a pipe to a socket 88983f9135bSJens Axboe * @inode: pipe inode 89083f9135bSJens Axboe * @out: socket to write to 89183f9135bSJens Axboe * @len: number of bytes to splice 89283f9135bSJens Axboe * @flags: splice modifier flags 89383f9135bSJens Axboe * 89483f9135bSJens Axboe * Will send @len bytes from the pipe to a network socket. No data copying 89583f9135bSJens Axboe * is involved. 89683f9135bSJens Axboe * 89783f9135bSJens Axboe */ 8983a326a2cSIngo Molnar ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe, struct file *out, 899cbb7e577SJens Axboe loff_t *ppos, size_t len, unsigned int flags) 9005274f052SJens Axboe { 90100522fb4SJens Axboe return splice_from_pipe(pipe, out, ppos, len, flags, pipe_to_sendpage); 9025274f052SJens Axboe } 9035274f052SJens Axboe 904059a8f37SJens Axboe EXPORT_SYMBOL(generic_splice_sendpage); 905a0f06780SJeff Garzik 90683f9135bSJens Axboe /* 90783f9135bSJens Axboe * Attempt to initiate a splice from pipe to file. 90883f9135bSJens Axboe */ 9093a326a2cSIngo Molnar static long do_splice_from(struct pipe_inode_info *pipe, struct file *out, 910cbb7e577SJens Axboe loff_t *ppos, size_t len, unsigned int flags) 9115274f052SJens Axboe { 9125274f052SJens Axboe int ret; 9135274f052SJens Axboe 91449570e9bSJens Axboe if (unlikely(!out->f_op || !out->f_op->splice_write)) 9155274f052SJens Axboe return -EINVAL; 9165274f052SJens Axboe 91749570e9bSJens Axboe if (unlikely(!(out->f_mode & FMODE_WRITE))) 9185274f052SJens Axboe return -EBADF; 9195274f052SJens Axboe 920cbb7e577SJens Axboe ret = rw_verify_area(WRITE, out, ppos, len); 9215274f052SJens Axboe if (unlikely(ret < 0)) 9225274f052SJens Axboe return ret; 9235274f052SJens Axboe 924cbb7e577SJens Axboe return out->f_op->splice_write(pipe, out, ppos, len, flags); 9255274f052SJens Axboe } 9265274f052SJens Axboe 92783f9135bSJens Axboe /* 92883f9135bSJens Axboe * Attempt to initiate a splice from a file to a pipe. 92983f9135bSJens Axboe */ 930cbb7e577SJens Axboe static long do_splice_to(struct file *in, loff_t *ppos, 931cbb7e577SJens Axboe struct pipe_inode_info *pipe, size_t len, 932cbb7e577SJens Axboe unsigned int flags) 9335274f052SJens Axboe { 9345274f052SJens Axboe int ret; 9355274f052SJens Axboe 93649570e9bSJens Axboe if (unlikely(!in->f_op || !in->f_op->splice_read)) 9375274f052SJens Axboe return -EINVAL; 9385274f052SJens Axboe 93949570e9bSJens Axboe if (unlikely(!(in->f_mode & FMODE_READ))) 9405274f052SJens Axboe return -EBADF; 9415274f052SJens Axboe 942cbb7e577SJens Axboe ret = rw_verify_area(READ, in, ppos, len); 9435274f052SJens Axboe if (unlikely(ret < 0)) 9445274f052SJens Axboe return ret; 9455274f052SJens Axboe 946cbb7e577SJens Axboe return in->f_op->splice_read(in, ppos, pipe, len, flags); 9475274f052SJens Axboe } 9485274f052SJens Axboe 949c66ab6faSJens Axboe /* 950c66ab6faSJens Axboe * Splices from an input file to an actor, using a 'direct' pipe. 951c66ab6faSJens Axboe */ 952c66ab6faSJens Axboe ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd, 953c66ab6faSJens Axboe splice_direct_actor *actor) 954b92ce558SJens Axboe { 955b92ce558SJens Axboe struct pipe_inode_info *pipe; 956b92ce558SJens Axboe long ret, bytes; 957b92ce558SJens Axboe umode_t i_mode; 958c66ab6faSJens Axboe size_t len; 959c66ab6faSJens Axboe int i, flags; 960b92ce558SJens Axboe 961b92ce558SJens Axboe /* 962b92ce558SJens Axboe * We require the input being a regular file, as we don't want to 963b92ce558SJens Axboe * randomly drop data for eg socket -> socket splicing. Use the 964b92ce558SJens Axboe * piped splicing for that! 965b92ce558SJens Axboe */ 9660f7fc9e4SJosef "Jeff" Sipek i_mode = in->f_path.dentry->d_inode->i_mode; 967b92ce558SJens Axboe if (unlikely(!S_ISREG(i_mode) && !S_ISBLK(i_mode))) 968b92ce558SJens Axboe return -EINVAL; 969b92ce558SJens Axboe 970b92ce558SJens Axboe /* 971b92ce558SJens Axboe * neither in nor out is a pipe, setup an internal pipe attached to 972b92ce558SJens Axboe * 'out' and transfer the wanted data from 'in' to 'out' through that 973b92ce558SJens Axboe */ 974b92ce558SJens Axboe pipe = current->splice_pipe; 97549570e9bSJens Axboe if (unlikely(!pipe)) { 976b92ce558SJens Axboe pipe = alloc_pipe_info(NULL); 977b92ce558SJens Axboe if (!pipe) 978b92ce558SJens Axboe return -ENOMEM; 979b92ce558SJens Axboe 980b92ce558SJens Axboe /* 981b92ce558SJens Axboe * We don't have an immediate reader, but we'll read the stuff 98200522fb4SJens Axboe * out of the pipe right after the splice_to_pipe(). So set 983b92ce558SJens Axboe * PIPE_READERS appropriately. 984b92ce558SJens Axboe */ 985b92ce558SJens Axboe pipe->readers = 1; 986b92ce558SJens Axboe 987b92ce558SJens Axboe current->splice_pipe = pipe; 988b92ce558SJens Axboe } 989b92ce558SJens Axboe 990b92ce558SJens Axboe /* 99173d62d83SIngo Molnar * Do the splice. 992b92ce558SJens Axboe */ 993b92ce558SJens Axboe ret = 0; 994b92ce558SJens Axboe bytes = 0; 995c66ab6faSJens Axboe len = sd->total_len; 996c66ab6faSJens Axboe flags = sd->flags; 997c66ab6faSJens Axboe 998c66ab6faSJens Axboe /* 999c66ab6faSJens Axboe * Don't block on output, we have to drain the direct pipe. 1000c66ab6faSJens Axboe */ 1001c66ab6faSJens Axboe sd->flags &= ~SPLICE_F_NONBLOCK; 1002b92ce558SJens Axboe 1003b92ce558SJens Axboe while (len) { 1004b92ce558SJens Axboe size_t read_len, max_read_len; 1005b92ce558SJens Axboe 1006b92ce558SJens Axboe /* 1007b92ce558SJens Axboe * Do at most PIPE_BUFFERS pages worth of transfer: 1008b92ce558SJens Axboe */ 1009b92ce558SJens Axboe max_read_len = min(len, (size_t)(PIPE_BUFFERS*PAGE_SIZE)); 1010b92ce558SJens Axboe 1011c66ab6faSJens Axboe ret = do_splice_to(in, &sd->pos, pipe, max_read_len, flags); 1012b92ce558SJens Axboe if (unlikely(ret < 0)) 1013b92ce558SJens Axboe goto out_release; 1014b92ce558SJens Axboe 1015b92ce558SJens Axboe read_len = ret; 1016c66ab6faSJens Axboe sd->total_len = read_len; 1017b92ce558SJens Axboe 1018b92ce558SJens Axboe /* 1019b92ce558SJens Axboe * NOTE: nonblocking mode only applies to the input. We 1020b92ce558SJens Axboe * must not do the output in nonblocking mode as then we 1021b92ce558SJens Axboe * could get stuck data in the internal pipe: 1022b92ce558SJens Axboe */ 1023c66ab6faSJens Axboe ret = actor(pipe, sd); 1024b92ce558SJens Axboe if (unlikely(ret < 0)) 1025b92ce558SJens Axboe goto out_release; 1026b92ce558SJens Axboe 1027b92ce558SJens Axboe bytes += ret; 1028b92ce558SJens Axboe len -= ret; 1029b92ce558SJens Axboe 1030b92ce558SJens Axboe /* 1031b92ce558SJens Axboe * In nonblocking mode, if we got back a short read then 1032b92ce558SJens Axboe * that was due to either an IO error or due to the 1033b92ce558SJens Axboe * pagecache entry not being there. In the IO error case 1034b92ce558SJens Axboe * the _next_ splice attempt will produce a clean IO error 1035b92ce558SJens Axboe * return value (not a short read), so in both cases it's 1036b92ce558SJens Axboe * correct to break out of the loop here: 1037b92ce558SJens Axboe */ 1038b92ce558SJens Axboe if ((flags & SPLICE_F_NONBLOCK) && (read_len < max_read_len)) 1039b92ce558SJens Axboe break; 1040b92ce558SJens Axboe } 1041b92ce558SJens Axboe 1042b92ce558SJens Axboe pipe->nrbufs = pipe->curbuf = 0; 1043b92ce558SJens Axboe 1044b92ce558SJens Axboe return bytes; 1045b92ce558SJens Axboe 1046b92ce558SJens Axboe out_release: 1047b92ce558SJens Axboe /* 1048b92ce558SJens Axboe * If we did an incomplete transfer we must release 1049b92ce558SJens Axboe * the pipe buffers in question: 1050b92ce558SJens Axboe */ 1051b92ce558SJens Axboe for (i = 0; i < PIPE_BUFFERS; i++) { 1052b92ce558SJens Axboe struct pipe_buffer *buf = pipe->bufs + i; 1053b92ce558SJens Axboe 1054b92ce558SJens Axboe if (buf->ops) { 1055b92ce558SJens Axboe buf->ops->release(pipe, buf); 1056b92ce558SJens Axboe buf->ops = NULL; 1057b92ce558SJens Axboe } 1058b92ce558SJens Axboe } 1059b92ce558SJens Axboe pipe->nrbufs = pipe->curbuf = 0; 1060b92ce558SJens Axboe 1061b92ce558SJens Axboe /* 1062b92ce558SJens Axboe * If we transferred some data, return the number of bytes: 1063b92ce558SJens Axboe */ 1064b92ce558SJens Axboe if (bytes > 0) 1065b92ce558SJens Axboe return bytes; 1066b92ce558SJens Axboe 1067b92ce558SJens Axboe return ret; 1068c66ab6faSJens Axboe 1069c66ab6faSJens Axboe } 1070c66ab6faSJens Axboe EXPORT_SYMBOL(splice_direct_to_actor); 1071c66ab6faSJens Axboe 1072c66ab6faSJens Axboe static int direct_splice_actor(struct pipe_inode_info *pipe, 1073c66ab6faSJens Axboe struct splice_desc *sd) 1074c66ab6faSJens Axboe { 10756a14b90bSJens Axboe struct file *file = sd->u.file; 1076c66ab6faSJens Axboe 1077c66ab6faSJens Axboe return do_splice_from(pipe, file, &sd->pos, sd->total_len, sd->flags); 1078c66ab6faSJens Axboe } 1079c66ab6faSJens Axboe 1080c66ab6faSJens Axboe long do_splice_direct(struct file *in, loff_t *ppos, struct file *out, 1081c66ab6faSJens Axboe size_t len, unsigned int flags) 1082c66ab6faSJens Axboe { 1083c66ab6faSJens Axboe struct splice_desc sd = { 1084c66ab6faSJens Axboe .len = len, 1085c66ab6faSJens Axboe .total_len = len, 1086c66ab6faSJens Axboe .flags = flags, 1087c66ab6faSJens Axboe .pos = *ppos, 10886a14b90bSJens Axboe .u.file = out, 1089c66ab6faSJens Axboe }; 1090c66ab6faSJens Axboe size_t ret; 1091c66ab6faSJens Axboe 1092c66ab6faSJens Axboe ret = splice_direct_to_actor(in, &sd, direct_splice_actor); 1093c66ab6faSJens Axboe *ppos = sd.pos; 1094c66ab6faSJens Axboe return ret; 1095b92ce558SJens Axboe } 1096b92ce558SJens Axboe 109783f9135bSJens Axboe /* 1098ddac0d39SJens Axboe * After the inode slimming patch, i_pipe/i_bdev/i_cdev share the same 1099ddac0d39SJens Axboe * location, so checking ->i_pipe is not enough to verify that this is a 1100ddac0d39SJens Axboe * pipe. 1101ddac0d39SJens Axboe */ 1102ddac0d39SJens Axboe static inline struct pipe_inode_info *pipe_info(struct inode *inode) 1103ddac0d39SJens Axboe { 1104ddac0d39SJens Axboe if (S_ISFIFO(inode->i_mode)) 1105ddac0d39SJens Axboe return inode->i_pipe; 1106ddac0d39SJens Axboe 1107ddac0d39SJens Axboe return NULL; 1108ddac0d39SJens Axboe } 1109ddac0d39SJens Axboe 1110ddac0d39SJens Axboe /* 111183f9135bSJens Axboe * Determine where to splice to/from. 111283f9135bSJens Axboe */ 1113529565dcSIngo Molnar static long do_splice(struct file *in, loff_t __user *off_in, 1114529565dcSIngo Molnar struct file *out, loff_t __user *off_out, 1115529565dcSIngo Molnar size_t len, unsigned int flags) 11165274f052SJens Axboe { 11173a326a2cSIngo Molnar struct pipe_inode_info *pipe; 1118cbb7e577SJens Axboe loff_t offset, *off; 1119a4514ebdSJens Axboe long ret; 11205274f052SJens Axboe 11210f7fc9e4SJosef "Jeff" Sipek pipe = pipe_info(in->f_path.dentry->d_inode); 1122529565dcSIngo Molnar if (pipe) { 1123529565dcSIngo Molnar if (off_in) 1124529565dcSIngo Molnar return -ESPIPE; 1125b92ce558SJens Axboe if (off_out) { 1126b92ce558SJens Axboe if (out->f_op->llseek == no_llseek) 1127b92ce558SJens Axboe return -EINVAL; 1128cbb7e577SJens Axboe if (copy_from_user(&offset, off_out, sizeof(loff_t))) 1129b92ce558SJens Axboe return -EFAULT; 1130cbb7e577SJens Axboe off = &offset; 1131cbb7e577SJens Axboe } else 1132cbb7e577SJens Axboe off = &out->f_pos; 1133529565dcSIngo Molnar 1134a4514ebdSJens Axboe ret = do_splice_from(pipe, out, off, len, flags); 1135a4514ebdSJens Axboe 1136a4514ebdSJens Axboe if (off_out && copy_to_user(off_out, off, sizeof(loff_t))) 1137a4514ebdSJens Axboe ret = -EFAULT; 1138a4514ebdSJens Axboe 1139a4514ebdSJens Axboe return ret; 1140529565dcSIngo Molnar } 11415274f052SJens Axboe 11420f7fc9e4SJosef "Jeff" Sipek pipe = pipe_info(out->f_path.dentry->d_inode); 1143529565dcSIngo Molnar if (pipe) { 1144529565dcSIngo Molnar if (off_out) 1145529565dcSIngo Molnar return -ESPIPE; 1146b92ce558SJens Axboe if (off_in) { 1147b92ce558SJens Axboe if (in->f_op->llseek == no_llseek) 1148b92ce558SJens Axboe return -EINVAL; 1149cbb7e577SJens Axboe if (copy_from_user(&offset, off_in, sizeof(loff_t))) 1150b92ce558SJens Axboe return -EFAULT; 1151cbb7e577SJens Axboe off = &offset; 1152cbb7e577SJens Axboe } else 1153cbb7e577SJens Axboe off = &in->f_pos; 1154529565dcSIngo Molnar 1155a4514ebdSJens Axboe ret = do_splice_to(in, off, pipe, len, flags); 1156a4514ebdSJens Axboe 1157a4514ebdSJens Axboe if (off_in && copy_to_user(off_in, off, sizeof(loff_t))) 1158a4514ebdSJens Axboe ret = -EFAULT; 1159a4514ebdSJens Axboe 1160a4514ebdSJens Axboe return ret; 1161529565dcSIngo Molnar } 11625274f052SJens Axboe 11635274f052SJens Axboe return -EINVAL; 11645274f052SJens Axboe } 11655274f052SJens Axboe 1166912d35f8SJens Axboe /* 1167912d35f8SJens Axboe * Map an iov into an array of pages and offset/length tupples. With the 1168912d35f8SJens Axboe * partial_page structure, we can map several non-contiguous ranges into 1169912d35f8SJens Axboe * our ones pages[] map instead of splitting that operation into pieces. 1170912d35f8SJens Axboe * Could easily be exported as a generic helper for other users, in which 1171912d35f8SJens Axboe * case one would probably want to add a 'max_nr_pages' parameter as well. 1172912d35f8SJens Axboe */ 1173912d35f8SJens Axboe static int get_iovec_page_array(const struct iovec __user *iov, 1174912d35f8SJens Axboe unsigned int nr_vecs, struct page **pages, 11757afa6fd0SJens Axboe struct partial_page *partial, int aligned) 1176912d35f8SJens Axboe { 1177912d35f8SJens Axboe int buffers = 0, error = 0; 1178912d35f8SJens Axboe 1179912d35f8SJens Axboe /* 1180912d35f8SJens Axboe * It's ok to take the mmap_sem for reading, even 1181912d35f8SJens Axboe * across a "get_user()". 1182912d35f8SJens Axboe */ 1183912d35f8SJens Axboe down_read(¤t->mm->mmap_sem); 1184912d35f8SJens Axboe 1185912d35f8SJens Axboe while (nr_vecs) { 1186912d35f8SJens Axboe unsigned long off, npages; 1187912d35f8SJens Axboe void __user *base; 1188912d35f8SJens Axboe size_t len; 1189912d35f8SJens Axboe int i; 1190912d35f8SJens Axboe 1191912d35f8SJens Axboe /* 1192912d35f8SJens Axboe * Get user address base and length for this iovec. 1193912d35f8SJens Axboe */ 1194912d35f8SJens Axboe error = get_user(base, &iov->iov_base); 1195912d35f8SJens Axboe if (unlikely(error)) 1196912d35f8SJens Axboe break; 1197912d35f8SJens Axboe error = get_user(len, &iov->iov_len); 1198912d35f8SJens Axboe if (unlikely(error)) 1199912d35f8SJens Axboe break; 1200912d35f8SJens Axboe 1201912d35f8SJens Axboe /* 1202912d35f8SJens Axboe * Sanity check this iovec. 0 read succeeds. 1203912d35f8SJens Axboe */ 1204912d35f8SJens Axboe if (unlikely(!len)) 1205912d35f8SJens Axboe break; 1206912d35f8SJens Axboe error = -EFAULT; 1207912d35f8SJens Axboe if (unlikely(!base)) 1208912d35f8SJens Axboe break; 1209912d35f8SJens Axboe 1210912d35f8SJens Axboe /* 1211912d35f8SJens Axboe * Get this base offset and number of pages, then map 1212912d35f8SJens Axboe * in the user pages. 1213912d35f8SJens Axboe */ 1214912d35f8SJens Axboe off = (unsigned long) base & ~PAGE_MASK; 12157afa6fd0SJens Axboe 12167afa6fd0SJens Axboe /* 12177afa6fd0SJens Axboe * If asked for alignment, the offset must be zero and the 12187afa6fd0SJens Axboe * length a multiple of the PAGE_SIZE. 12197afa6fd0SJens Axboe */ 12207afa6fd0SJens Axboe error = -EINVAL; 12217afa6fd0SJens Axboe if (aligned && (off || len & ~PAGE_MASK)) 12227afa6fd0SJens Axboe break; 12237afa6fd0SJens Axboe 1224912d35f8SJens Axboe npages = (off + len + PAGE_SIZE - 1) >> PAGE_SHIFT; 1225912d35f8SJens Axboe if (npages > PIPE_BUFFERS - buffers) 1226912d35f8SJens Axboe npages = PIPE_BUFFERS - buffers; 1227912d35f8SJens Axboe 1228912d35f8SJens Axboe error = get_user_pages(current, current->mm, 1229912d35f8SJens Axboe (unsigned long) base, npages, 0, 0, 1230912d35f8SJens Axboe &pages[buffers], NULL); 1231912d35f8SJens Axboe 1232912d35f8SJens Axboe if (unlikely(error <= 0)) 1233912d35f8SJens Axboe break; 1234912d35f8SJens Axboe 1235912d35f8SJens Axboe /* 1236912d35f8SJens Axboe * Fill this contiguous range into the partial page map. 1237912d35f8SJens Axboe */ 1238912d35f8SJens Axboe for (i = 0; i < error; i++) { 12397591489aSJens Axboe const int plen = min_t(size_t, len, PAGE_SIZE - off); 1240912d35f8SJens Axboe 1241912d35f8SJens Axboe partial[buffers].offset = off; 1242912d35f8SJens Axboe partial[buffers].len = plen; 1243912d35f8SJens Axboe 1244912d35f8SJens Axboe off = 0; 1245912d35f8SJens Axboe len -= plen; 1246912d35f8SJens Axboe buffers++; 1247912d35f8SJens Axboe } 1248912d35f8SJens Axboe 1249912d35f8SJens Axboe /* 1250912d35f8SJens Axboe * We didn't complete this iov, stop here since it probably 1251912d35f8SJens Axboe * means we have to move some of this into a pipe to 1252912d35f8SJens Axboe * be able to continue. 1253912d35f8SJens Axboe */ 1254912d35f8SJens Axboe if (len) 1255912d35f8SJens Axboe break; 1256912d35f8SJens Axboe 1257912d35f8SJens Axboe /* 1258912d35f8SJens Axboe * Don't continue if we mapped fewer pages than we asked for, 1259912d35f8SJens Axboe * or if we mapped the max number of pages that we have 1260912d35f8SJens Axboe * room for. 1261912d35f8SJens Axboe */ 1262912d35f8SJens Axboe if (error < npages || buffers == PIPE_BUFFERS) 1263912d35f8SJens Axboe break; 1264912d35f8SJens Axboe 1265912d35f8SJens Axboe nr_vecs--; 1266912d35f8SJens Axboe iov++; 1267912d35f8SJens Axboe } 1268912d35f8SJens Axboe 1269912d35f8SJens Axboe up_read(¤t->mm->mmap_sem); 1270912d35f8SJens Axboe 1271912d35f8SJens Axboe if (buffers) 1272912d35f8SJens Axboe return buffers; 1273912d35f8SJens Axboe 1274912d35f8SJens Axboe return error; 1275912d35f8SJens Axboe } 1276912d35f8SJens Axboe 12776a14b90bSJens Axboe static int pipe_to_user(struct pipe_inode_info *pipe, struct pipe_buffer *buf, 12786a14b90bSJens Axboe struct splice_desc *sd) 12796a14b90bSJens Axboe { 12806a14b90bSJens Axboe char *src; 12816a14b90bSJens Axboe int ret; 12826a14b90bSJens Axboe 12836a14b90bSJens Axboe ret = buf->ops->pin(pipe, buf); 12846a14b90bSJens Axboe if (unlikely(ret)) 12856a14b90bSJens Axboe return ret; 12866a14b90bSJens Axboe 12876a14b90bSJens Axboe /* 12886a14b90bSJens Axboe * See if we can use the atomic maps, by prefaulting in the 12896a14b90bSJens Axboe * pages and doing an atomic copy 12906a14b90bSJens Axboe */ 12916a14b90bSJens Axboe if (!fault_in_pages_writeable(sd->u.userptr, sd->len)) { 12926a14b90bSJens Axboe src = buf->ops->map(pipe, buf, 1); 12936a14b90bSJens Axboe ret = __copy_to_user_inatomic(sd->u.userptr, src + buf->offset, 12946a14b90bSJens Axboe sd->len); 12956a14b90bSJens Axboe buf->ops->unmap(pipe, buf, src); 12966a14b90bSJens Axboe if (!ret) { 12976a14b90bSJens Axboe ret = sd->len; 12986a14b90bSJens Axboe goto out; 12996a14b90bSJens Axboe } 13006a14b90bSJens Axboe } 13016a14b90bSJens Axboe 13026a14b90bSJens Axboe /* 13036a14b90bSJens Axboe * No dice, use slow non-atomic map and copy 13046a14b90bSJens Axboe */ 13056a14b90bSJens Axboe src = buf->ops->map(pipe, buf, 0); 13066a14b90bSJens Axboe 13076a14b90bSJens Axboe ret = sd->len; 13086a14b90bSJens Axboe if (copy_to_user(sd->u.userptr, src + buf->offset, sd->len)) 13096a14b90bSJens Axboe ret = -EFAULT; 13106a14b90bSJens Axboe 13116a14b90bSJens Axboe out: 13126a14b90bSJens Axboe if (ret > 0) 13136a14b90bSJens Axboe sd->u.userptr += ret; 13146a14b90bSJens Axboe buf->ops->unmap(pipe, buf, src); 13156a14b90bSJens Axboe return ret; 13166a14b90bSJens Axboe } 13176a14b90bSJens Axboe 13186a14b90bSJens Axboe /* 13196a14b90bSJens Axboe * For lack of a better implementation, implement vmsplice() to userspace 13206a14b90bSJens Axboe * as a simple copy of the pipes pages to the user iov. 13216a14b90bSJens Axboe */ 13226a14b90bSJens Axboe static long vmsplice_to_user(struct file *file, const struct iovec __user *iov, 13236a14b90bSJens Axboe unsigned long nr_segs, unsigned int flags) 13246a14b90bSJens Axboe { 13256a14b90bSJens Axboe struct pipe_inode_info *pipe; 13266a14b90bSJens Axboe struct splice_desc sd; 13276a14b90bSJens Axboe ssize_t size; 13286a14b90bSJens Axboe int error; 13296a14b90bSJens Axboe long ret; 13306a14b90bSJens Axboe 13316a14b90bSJens Axboe pipe = pipe_info(file->f_path.dentry->d_inode); 13326a14b90bSJens Axboe if (!pipe) 13336a14b90bSJens Axboe return -EBADF; 13346a14b90bSJens Axboe 13356a14b90bSJens Axboe if (pipe->inode) 13366a14b90bSJens Axboe mutex_lock(&pipe->inode->i_mutex); 13376a14b90bSJens Axboe 13386a14b90bSJens Axboe error = ret = 0; 13396a14b90bSJens Axboe while (nr_segs) { 13406a14b90bSJens Axboe void __user *base; 13416a14b90bSJens Axboe size_t len; 13426a14b90bSJens Axboe 13436a14b90bSJens Axboe /* 13446a14b90bSJens Axboe * Get user address base and length for this iovec. 13456a14b90bSJens Axboe */ 13466a14b90bSJens Axboe error = get_user(base, &iov->iov_base); 13476a14b90bSJens Axboe if (unlikely(error)) 13486a14b90bSJens Axboe break; 13496a14b90bSJens Axboe error = get_user(len, &iov->iov_len); 13506a14b90bSJens Axboe if (unlikely(error)) 13516a14b90bSJens Axboe break; 13526a14b90bSJens Axboe 13536a14b90bSJens Axboe /* 13546a14b90bSJens Axboe * Sanity check this iovec. 0 read succeeds. 13556a14b90bSJens Axboe */ 13566a14b90bSJens Axboe if (unlikely(!len)) 13576a14b90bSJens Axboe break; 13586a14b90bSJens Axboe if (unlikely(!base)) { 13596a14b90bSJens Axboe error = -EFAULT; 13606a14b90bSJens Axboe break; 13616a14b90bSJens Axboe } 13626a14b90bSJens Axboe 13636a14b90bSJens Axboe sd.len = 0; 13646a14b90bSJens Axboe sd.total_len = len; 13656a14b90bSJens Axboe sd.flags = flags; 13666a14b90bSJens Axboe sd.u.userptr = base; 13676a14b90bSJens Axboe sd.pos = 0; 13686a14b90bSJens Axboe 13696a14b90bSJens Axboe size = __splice_from_pipe(pipe, &sd, pipe_to_user); 13706a14b90bSJens Axboe if (size < 0) { 13716a14b90bSJens Axboe if (!ret) 13726a14b90bSJens Axboe ret = size; 13736a14b90bSJens Axboe 13746a14b90bSJens Axboe break; 13756a14b90bSJens Axboe } 13766a14b90bSJens Axboe 13776a14b90bSJens Axboe ret += size; 13786a14b90bSJens Axboe 13796a14b90bSJens Axboe if (size < len) 13806a14b90bSJens Axboe break; 13816a14b90bSJens Axboe 13826a14b90bSJens Axboe nr_segs--; 13836a14b90bSJens Axboe iov++; 13846a14b90bSJens Axboe } 13856a14b90bSJens Axboe 13866a14b90bSJens Axboe if (pipe->inode) 13876a14b90bSJens Axboe mutex_unlock(&pipe->inode->i_mutex); 13886a14b90bSJens Axboe 13896a14b90bSJens Axboe if (!ret) 13906a14b90bSJens Axboe ret = error; 13916a14b90bSJens Axboe 13926a14b90bSJens Axboe return ret; 13936a14b90bSJens Axboe } 13946a14b90bSJens Axboe 1395912d35f8SJens Axboe /* 1396912d35f8SJens Axboe * vmsplice splices a user address range into a pipe. It can be thought of 1397912d35f8SJens Axboe * as splice-from-memory, where the regular splice is splice-from-file (or 1398912d35f8SJens Axboe * to file). In both cases the output is a pipe, naturally. 1399912d35f8SJens Axboe */ 14006a14b90bSJens Axboe static long vmsplice_to_pipe(struct file *file, const struct iovec __user *iov, 1401912d35f8SJens Axboe unsigned long nr_segs, unsigned int flags) 1402912d35f8SJens Axboe { 1403ddac0d39SJens Axboe struct pipe_inode_info *pipe; 1404912d35f8SJens Axboe struct page *pages[PIPE_BUFFERS]; 1405912d35f8SJens Axboe struct partial_page partial[PIPE_BUFFERS]; 1406912d35f8SJens Axboe struct splice_pipe_desc spd = { 1407912d35f8SJens Axboe .pages = pages, 1408912d35f8SJens Axboe .partial = partial, 1409912d35f8SJens Axboe .flags = flags, 1410912d35f8SJens Axboe .ops = &user_page_pipe_buf_ops, 1411912d35f8SJens Axboe }; 1412912d35f8SJens Axboe 14130f7fc9e4SJosef "Jeff" Sipek pipe = pipe_info(file->f_path.dentry->d_inode); 1414ddac0d39SJens Axboe if (!pipe) 1415912d35f8SJens Axboe return -EBADF; 1416912d35f8SJens Axboe 14177afa6fd0SJens Axboe spd.nr_pages = get_iovec_page_array(iov, nr_segs, pages, partial, 14187afa6fd0SJens Axboe flags & SPLICE_F_GIFT); 1419912d35f8SJens Axboe if (spd.nr_pages <= 0) 1420912d35f8SJens Axboe return spd.nr_pages; 1421912d35f8SJens Axboe 142200522fb4SJens Axboe return splice_to_pipe(pipe, &spd); 1423912d35f8SJens Axboe } 1424912d35f8SJens Axboe 14256a14b90bSJens Axboe /* 14266a14b90bSJens Axboe * Note that vmsplice only really supports true splicing _from_ user memory 14276a14b90bSJens Axboe * to a pipe, not the other way around. Splicing from user memory is a simple 14286a14b90bSJens Axboe * operation that can be supported without any funky alignment restrictions 14296a14b90bSJens Axboe * or nasty vm tricks. We simply map in the user memory and fill them into 14306a14b90bSJens Axboe * a pipe. The reverse isn't quite as easy, though. There are two possible 14316a14b90bSJens Axboe * solutions for that: 14326a14b90bSJens Axboe * 14336a14b90bSJens Axboe * - memcpy() the data internally, at which point we might as well just 14346a14b90bSJens Axboe * do a regular read() on the buffer anyway. 14356a14b90bSJens Axboe * - Lots of nasty vm tricks, that are neither fast nor flexible (it 14366a14b90bSJens Axboe * has restriction limitations on both ends of the pipe). 14376a14b90bSJens Axboe * 14386a14b90bSJens Axboe * Currently we punt and implement it as a normal copy, see pipe_to_user(). 14396a14b90bSJens Axboe * 14406a14b90bSJens Axboe */ 1441912d35f8SJens Axboe asmlinkage long sys_vmsplice(int fd, const struct iovec __user *iov, 1442912d35f8SJens Axboe unsigned long nr_segs, unsigned int flags) 1443912d35f8SJens Axboe { 1444912d35f8SJens Axboe struct file *file; 1445912d35f8SJens Axboe long error; 1446912d35f8SJens Axboe int fput; 1447912d35f8SJens Axboe 14486a14b90bSJens Axboe if (unlikely(nr_segs > UIO_MAXIOV)) 14496a14b90bSJens Axboe return -EINVAL; 14506a14b90bSJens Axboe else if (unlikely(!nr_segs)) 14516a14b90bSJens Axboe return 0; 14526a14b90bSJens Axboe 1453912d35f8SJens Axboe error = -EBADF; 1454912d35f8SJens Axboe file = fget_light(fd, &fput); 1455912d35f8SJens Axboe if (file) { 1456912d35f8SJens Axboe if (file->f_mode & FMODE_WRITE) 14576a14b90bSJens Axboe error = vmsplice_to_pipe(file, iov, nr_segs, flags); 14586a14b90bSJens Axboe else if (file->f_mode & FMODE_READ) 14596a14b90bSJens Axboe error = vmsplice_to_user(file, iov, nr_segs, flags); 1460912d35f8SJens Axboe 1461912d35f8SJens Axboe fput_light(file, fput); 1462912d35f8SJens Axboe } 1463912d35f8SJens Axboe 1464912d35f8SJens Axboe return error; 1465912d35f8SJens Axboe } 1466912d35f8SJens Axboe 1467529565dcSIngo Molnar asmlinkage long sys_splice(int fd_in, loff_t __user *off_in, 1468529565dcSIngo Molnar int fd_out, loff_t __user *off_out, 1469529565dcSIngo Molnar size_t len, unsigned int flags) 14705274f052SJens Axboe { 14715274f052SJens Axboe long error; 14725274f052SJens Axboe struct file *in, *out; 14735274f052SJens Axboe int fput_in, fput_out; 14745274f052SJens Axboe 14755274f052SJens Axboe if (unlikely(!len)) 14765274f052SJens Axboe return 0; 14775274f052SJens Axboe 14785274f052SJens Axboe error = -EBADF; 1479529565dcSIngo Molnar in = fget_light(fd_in, &fput_in); 14805274f052SJens Axboe if (in) { 14815274f052SJens Axboe if (in->f_mode & FMODE_READ) { 1482529565dcSIngo Molnar out = fget_light(fd_out, &fput_out); 14835274f052SJens Axboe if (out) { 14845274f052SJens Axboe if (out->f_mode & FMODE_WRITE) 1485529565dcSIngo Molnar error = do_splice(in, off_in, 1486529565dcSIngo Molnar out, off_out, 1487529565dcSIngo Molnar len, flags); 14885274f052SJens Axboe fput_light(out, fput_out); 14895274f052SJens Axboe } 14905274f052SJens Axboe } 14915274f052SJens Axboe 14925274f052SJens Axboe fput_light(in, fput_in); 14935274f052SJens Axboe } 14945274f052SJens Axboe 14955274f052SJens Axboe return error; 14965274f052SJens Axboe } 149770524490SJens Axboe 149870524490SJens Axboe /* 1499aadd06e5SJens Axboe * Make sure there's data to read. Wait for input if we can, otherwise 1500aadd06e5SJens Axboe * return an appropriate error. 1501aadd06e5SJens Axboe */ 1502aadd06e5SJens Axboe static int link_ipipe_prep(struct pipe_inode_info *pipe, unsigned int flags) 1503aadd06e5SJens Axboe { 1504aadd06e5SJens Axboe int ret; 1505aadd06e5SJens Axboe 1506aadd06e5SJens Axboe /* 1507aadd06e5SJens Axboe * Check ->nrbufs without the inode lock first. This function 1508aadd06e5SJens Axboe * is speculative anyways, so missing one is ok. 1509aadd06e5SJens Axboe */ 1510aadd06e5SJens Axboe if (pipe->nrbufs) 1511aadd06e5SJens Axboe return 0; 1512aadd06e5SJens Axboe 1513aadd06e5SJens Axboe ret = 0; 1514aadd06e5SJens Axboe mutex_lock(&pipe->inode->i_mutex); 1515aadd06e5SJens Axboe 1516aadd06e5SJens Axboe while (!pipe->nrbufs) { 1517aadd06e5SJens Axboe if (signal_pending(current)) { 1518aadd06e5SJens Axboe ret = -ERESTARTSYS; 1519aadd06e5SJens Axboe break; 1520aadd06e5SJens Axboe } 1521aadd06e5SJens Axboe if (!pipe->writers) 1522aadd06e5SJens Axboe break; 1523aadd06e5SJens Axboe if (!pipe->waiting_writers) { 1524aadd06e5SJens Axboe if (flags & SPLICE_F_NONBLOCK) { 1525aadd06e5SJens Axboe ret = -EAGAIN; 1526aadd06e5SJens Axboe break; 1527aadd06e5SJens Axboe } 1528aadd06e5SJens Axboe } 1529aadd06e5SJens Axboe pipe_wait(pipe); 1530aadd06e5SJens Axboe } 1531aadd06e5SJens Axboe 1532aadd06e5SJens Axboe mutex_unlock(&pipe->inode->i_mutex); 1533aadd06e5SJens Axboe return ret; 1534aadd06e5SJens Axboe } 1535aadd06e5SJens Axboe 1536aadd06e5SJens Axboe /* 1537aadd06e5SJens Axboe * Make sure there's writeable room. Wait for room if we can, otherwise 1538aadd06e5SJens Axboe * return an appropriate error. 1539aadd06e5SJens Axboe */ 1540aadd06e5SJens Axboe static int link_opipe_prep(struct pipe_inode_info *pipe, unsigned int flags) 1541aadd06e5SJens Axboe { 1542aadd06e5SJens Axboe int ret; 1543aadd06e5SJens Axboe 1544aadd06e5SJens Axboe /* 1545aadd06e5SJens Axboe * Check ->nrbufs without the inode lock first. This function 1546aadd06e5SJens Axboe * is speculative anyways, so missing one is ok. 1547aadd06e5SJens Axboe */ 1548aadd06e5SJens Axboe if (pipe->nrbufs < PIPE_BUFFERS) 1549aadd06e5SJens Axboe return 0; 1550aadd06e5SJens Axboe 1551aadd06e5SJens Axboe ret = 0; 1552aadd06e5SJens Axboe mutex_lock(&pipe->inode->i_mutex); 1553aadd06e5SJens Axboe 1554aadd06e5SJens Axboe while (pipe->nrbufs >= PIPE_BUFFERS) { 1555aadd06e5SJens Axboe if (!pipe->readers) { 1556aadd06e5SJens Axboe send_sig(SIGPIPE, current, 0); 1557aadd06e5SJens Axboe ret = -EPIPE; 1558aadd06e5SJens Axboe break; 1559aadd06e5SJens Axboe } 1560aadd06e5SJens Axboe if (flags & SPLICE_F_NONBLOCK) { 1561aadd06e5SJens Axboe ret = -EAGAIN; 1562aadd06e5SJens Axboe break; 1563aadd06e5SJens Axboe } 1564aadd06e5SJens Axboe if (signal_pending(current)) { 1565aadd06e5SJens Axboe ret = -ERESTARTSYS; 1566aadd06e5SJens Axboe break; 1567aadd06e5SJens Axboe } 1568aadd06e5SJens Axboe pipe->waiting_writers++; 1569aadd06e5SJens Axboe pipe_wait(pipe); 1570aadd06e5SJens Axboe pipe->waiting_writers--; 1571aadd06e5SJens Axboe } 1572aadd06e5SJens Axboe 1573aadd06e5SJens Axboe mutex_unlock(&pipe->inode->i_mutex); 1574aadd06e5SJens Axboe return ret; 1575aadd06e5SJens Axboe } 1576aadd06e5SJens Axboe 1577aadd06e5SJens Axboe /* 157870524490SJens Axboe * Link contents of ipipe to opipe. 157970524490SJens Axboe */ 158070524490SJens Axboe static int link_pipe(struct pipe_inode_info *ipipe, 158170524490SJens Axboe struct pipe_inode_info *opipe, 158270524490SJens Axboe size_t len, unsigned int flags) 158370524490SJens Axboe { 158470524490SJens Axboe struct pipe_buffer *ibuf, *obuf; 1585aadd06e5SJens Axboe int ret = 0, i = 0, nbuf; 158670524490SJens Axboe 158770524490SJens Axboe /* 158870524490SJens Axboe * Potential ABBA deadlock, work around it by ordering lock 158970524490SJens Axboe * grabbing by inode address. Otherwise two different processes 159070524490SJens Axboe * could deadlock (one doing tee from A -> B, the other from B -> A). 159170524490SJens Axboe */ 159262752ee1SMark Fasheh inode_double_lock(ipipe->inode, opipe->inode); 159370524490SJens Axboe 1594aadd06e5SJens Axboe do { 159570524490SJens Axboe if (!opipe->readers) { 159670524490SJens Axboe send_sig(SIGPIPE, current, 0); 159770524490SJens Axboe if (!ret) 159870524490SJens Axboe ret = -EPIPE; 159970524490SJens Axboe break; 160070524490SJens Axboe } 160170524490SJens Axboe 160270524490SJens Axboe /* 1603aadd06e5SJens Axboe * If we have iterated all input buffers or ran out of 1604aadd06e5SJens Axboe * output room, break. 160570524490SJens Axboe */ 1606aadd06e5SJens Axboe if (i >= ipipe->nrbufs || opipe->nrbufs >= PIPE_BUFFERS) 1607aadd06e5SJens Axboe break; 1608aadd06e5SJens Axboe 1609aadd06e5SJens Axboe ibuf = ipipe->bufs + ((ipipe->curbuf + i) & (PIPE_BUFFERS - 1)); 1610aadd06e5SJens Axboe nbuf = (opipe->curbuf + opipe->nrbufs) & (PIPE_BUFFERS - 1); 161170524490SJens Axboe 161270524490SJens Axboe /* 161370524490SJens Axboe * Get a reference to this pipe buffer, 161470524490SJens Axboe * so we can copy the contents over. 161570524490SJens Axboe */ 161670524490SJens Axboe ibuf->ops->get(ipipe, ibuf); 161770524490SJens Axboe 161870524490SJens Axboe obuf = opipe->bufs + nbuf; 161970524490SJens Axboe *obuf = *ibuf; 162070524490SJens Axboe 16217afa6fd0SJens Axboe /* 16227afa6fd0SJens Axboe * Don't inherit the gift flag, we need to 16237afa6fd0SJens Axboe * prevent multiple steals of this page. 16247afa6fd0SJens Axboe */ 16257afa6fd0SJens Axboe obuf->flags &= ~PIPE_BUF_FLAG_GIFT; 16267afa6fd0SJens Axboe 162770524490SJens Axboe if (obuf->len > len) 162870524490SJens Axboe obuf->len = len; 162970524490SJens Axboe 163070524490SJens Axboe opipe->nrbufs++; 163170524490SJens Axboe ret += obuf->len; 163270524490SJens Axboe len -= obuf->len; 1633aadd06e5SJens Axboe i++; 1634aadd06e5SJens Axboe } while (len); 163570524490SJens Axboe 163662752ee1SMark Fasheh inode_double_unlock(ipipe->inode, opipe->inode); 163770524490SJens Axboe 1638aadd06e5SJens Axboe /* 1639aadd06e5SJens Axboe * If we put data in the output pipe, wakeup any potential readers. 1640aadd06e5SJens Axboe */ 1641aadd06e5SJens Axboe if (ret > 0) { 164270524490SJens Axboe smp_mb(); 164370524490SJens Axboe if (waitqueue_active(&opipe->wait)) 164470524490SJens Axboe wake_up_interruptible(&opipe->wait); 164570524490SJens Axboe kill_fasync(&opipe->fasync_readers, SIGIO, POLL_IN); 164670524490SJens Axboe } 164770524490SJens Axboe 164870524490SJens Axboe return ret; 164970524490SJens Axboe } 165070524490SJens Axboe 165170524490SJens Axboe /* 165270524490SJens Axboe * This is a tee(1) implementation that works on pipes. It doesn't copy 165370524490SJens Axboe * any data, it simply references the 'in' pages on the 'out' pipe. 165470524490SJens Axboe * The 'flags' used are the SPLICE_F_* variants, currently the only 165570524490SJens Axboe * applicable one is SPLICE_F_NONBLOCK. 165670524490SJens Axboe */ 165770524490SJens Axboe static long do_tee(struct file *in, struct file *out, size_t len, 165870524490SJens Axboe unsigned int flags) 165970524490SJens Axboe { 16600f7fc9e4SJosef "Jeff" Sipek struct pipe_inode_info *ipipe = pipe_info(in->f_path.dentry->d_inode); 16610f7fc9e4SJosef "Jeff" Sipek struct pipe_inode_info *opipe = pipe_info(out->f_path.dentry->d_inode); 1662aadd06e5SJens Axboe int ret = -EINVAL; 166370524490SJens Axboe 166470524490SJens Axboe /* 1665aadd06e5SJens Axboe * Duplicate the contents of ipipe to opipe without actually 1666aadd06e5SJens Axboe * copying the data. 166770524490SJens Axboe */ 1668aadd06e5SJens Axboe if (ipipe && opipe && ipipe != opipe) { 1669aadd06e5SJens Axboe /* 1670aadd06e5SJens Axboe * Keep going, unless we encounter an error. The ipipe/opipe 1671aadd06e5SJens Axboe * ordering doesn't really matter. 1672aadd06e5SJens Axboe */ 1673aadd06e5SJens Axboe ret = link_ipipe_prep(ipipe, flags); 1674aadd06e5SJens Axboe if (!ret) { 1675aadd06e5SJens Axboe ret = link_opipe_prep(opipe, flags); 1676aadd06e5SJens Axboe if (!ret) { 1677aadd06e5SJens Axboe ret = link_pipe(ipipe, opipe, len, flags); 1678aadd06e5SJens Axboe if (!ret && (flags & SPLICE_F_NONBLOCK)) 1679aadd06e5SJens Axboe ret = -EAGAIN; 1680aadd06e5SJens Axboe } 1681aadd06e5SJens Axboe } 1682aadd06e5SJens Axboe } 168370524490SJens Axboe 1684aadd06e5SJens Axboe return ret; 168570524490SJens Axboe } 168670524490SJens Axboe 168770524490SJens Axboe asmlinkage long sys_tee(int fdin, int fdout, size_t len, unsigned int flags) 168870524490SJens Axboe { 168970524490SJens Axboe struct file *in; 169070524490SJens Axboe int error, fput_in; 169170524490SJens Axboe 169270524490SJens Axboe if (unlikely(!len)) 169370524490SJens Axboe return 0; 169470524490SJens Axboe 169570524490SJens Axboe error = -EBADF; 169670524490SJens Axboe in = fget_light(fdin, &fput_in); 169770524490SJens Axboe if (in) { 169870524490SJens Axboe if (in->f_mode & FMODE_READ) { 169970524490SJens Axboe int fput_out; 170070524490SJens Axboe struct file *out = fget_light(fdout, &fput_out); 170170524490SJens Axboe 170270524490SJens Axboe if (out) { 170370524490SJens Axboe if (out->f_mode & FMODE_WRITE) 170470524490SJens Axboe error = do_tee(in, out, len, flags); 170570524490SJens Axboe fput_light(out, fput_out); 170670524490SJens Axboe } 170770524490SJens Axboe } 170870524490SJens Axboe fput_light(in, fput_in); 170970524490SJens Axboe } 171070524490SJens Axboe 171170524490SJens Axboe return error; 171270524490SJens Axboe } 1713