diff options
author | Linus Torvalds | 2016-10-08 00:36:58 +0200 |
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committer | Linus Torvalds | 2016-10-08 00:36:58 +0200 |
commit | d1f5323370fceaed43a7ee38f4c7bfc7e70f28d0 (patch) | |
tree | cadb1dc22207a4e1838b7af31ac3fc15363e809b /fs | |
parent | Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/t... (diff) | |
parent | pipe: fix comment in pipe_buf_operations (diff) | |
download | kernel-qcow2-linux-d1f5323370fceaed43a7ee38f4c7bfc7e70f28d0.tar.gz kernel-qcow2-linux-d1f5323370fceaed43a7ee38f4c7bfc7e70f28d0.tar.xz kernel-qcow2-linux-d1f5323370fceaed43a7ee38f4c7bfc7e70f28d0.zip |
Merge branch 'work.splice_read' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull VFS splice updates from Al Viro:
"There's a bunch of branches this cycle, both mine and from other folks
and I'd rather send pull requests separately.
This one is the conversion of ->splice_read() to ITER_PIPE iov_iter
(and introduction of such). Gets rid of a lot of code in fs/splice.c
and elsewhere; there will be followups, but these are for the next
cycle... Some pipe/splice-related cleanups from Miklos in the same
branch as well"
* 'work.splice_read' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
pipe: fix comment in pipe_buf_operations
pipe: add pipe_buf_steal() helper
pipe: add pipe_buf_confirm() helper
pipe: add pipe_buf_release() helper
pipe: add pipe_buf_get() helper
relay: simplify relay_file_read()
switch default_file_splice_read() to use of pipe-backed iov_iter
switch generic_file_splice_read() to use of ->read_iter()
new iov_iter flavour: pipe-backed
fuse_dev_splice_read(): switch to add_to_pipe()
skb_splice_bits(): get rid of callback
new helper: add_to_pipe()
splice: lift pipe_lock out of splice_to_pipe()
splice: switch get_iovec_page_array() to iov_iter
splice_to_pipe(): don't open-code wakeup_pipe_readers()
consistent treatment of EFAULT on O_DIRECT read/write
Diffstat (limited to 'fs')
-rw-r--r-- | fs/coda/file.c | 23 | ||||
-rw-r--r-- | fs/direct-io.c | 3 | ||||
-rw-r--r-- | fs/fuse/dev.c | 63 | ||||
-rw-r--r-- | fs/gfs2/file.c | 28 | ||||
-rw-r--r-- | fs/nfs/file.c | 25 | ||||
-rw-r--r-- | fs/nfs/internal.h | 2 | ||||
-rw-r--r-- | fs/nfs/nfs4file.c | 2 | ||||
-rw-r--r-- | fs/ocfs2/file.c | 34 | ||||
-rw-r--r-- | fs/ocfs2/ocfs2_trace.h | 2 | ||||
-rw-r--r-- | fs/pipe.c | 13 | ||||
-rw-r--r-- | fs/splice.c | 683 | ||||
-rw-r--r-- | fs/xfs/xfs_file.c | 41 | ||||
-rw-r--r-- | fs/xfs/xfs_trace.h | 1 |
13 files changed, 230 insertions, 690 deletions
diff --git a/fs/coda/file.c b/fs/coda/file.c index f47c7483863b..8415d4f8d1a1 100644 --- a/fs/coda/file.c +++ b/fs/coda/file.c @@ -38,27 +38,6 @@ coda_file_read_iter(struct kiocb *iocb, struct iov_iter *to) } static ssize_t -coda_file_splice_read(struct file *coda_file, loff_t *ppos, - struct pipe_inode_info *pipe, size_t count, - unsigned int flags) -{ - ssize_t (*splice_read)(struct file *, loff_t *, - struct pipe_inode_info *, size_t, unsigned int); - struct coda_file_info *cfi; - struct file *host_file; - - cfi = CODA_FTOC(coda_file); - BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); - host_file = cfi->cfi_container; - - splice_read = host_file->f_op->splice_read; - if (!splice_read) - splice_read = default_file_splice_read; - - return splice_read(host_file, ppos, pipe, count, flags); -} - -static ssize_t coda_file_write_iter(struct kiocb *iocb, struct iov_iter *to) { struct file *coda_file = iocb->ki_filp; @@ -225,6 +204,6 @@ const struct file_operations coda_file_operations = { .open = coda_open, .release = coda_release, .fsync = coda_fsync, - .splice_read = coda_file_splice_read, + .splice_read = generic_file_splice_read, }; diff --git a/fs/direct-io.c b/fs/direct-io.c index 7c3ce73cb617..fb9aa16a7727 100644 --- a/fs/direct-io.c +++ b/fs/direct-io.c @@ -246,6 +246,9 @@ static ssize_t dio_complete(struct dio *dio, ssize_t ret, bool is_async) if ((dio->op == REQ_OP_READ) && ((offset + transferred) > dio->i_size)) transferred = dio->i_size - offset; + /* ignore EFAULT if some IO has been done */ + if (unlikely(ret == -EFAULT) && transferred) + ret = 0; } if (ret == 0) diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index c41bde26c338..70ea57c7b6bb 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -728,7 +728,7 @@ static int fuse_copy_fill(struct fuse_copy_state *cs) struct pipe_buffer *buf = cs->pipebufs; if (!cs->write) { - err = buf->ops->confirm(cs->pipe, buf); + err = pipe_buf_confirm(cs->pipe, buf); if (err) return err; @@ -827,7 +827,7 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep) fuse_copy_finish(cs); - err = buf->ops->confirm(cs->pipe, buf); + err = pipe_buf_confirm(cs->pipe, buf); if (err) return err; @@ -840,7 +840,7 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep) if (cs->len != PAGE_SIZE) goto out_fallback; - if (buf->ops->steal(cs->pipe, buf) != 0) + if (pipe_buf_steal(cs->pipe, buf) != 0) goto out_fallback; newpage = buf->page; @@ -1341,9 +1341,8 @@ static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags) { - int ret; + int total, ret; int page_nr = 0; - int do_wakeup = 0; struct pipe_buffer *bufs; struct fuse_copy_state cs; struct fuse_dev *fud = fuse_get_dev(in); @@ -1362,52 +1361,23 @@ static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos, if (ret < 0) goto out; - ret = 0; - pipe_lock(pipe); - - if (!pipe->readers) { - send_sig(SIGPIPE, current, 0); - if (!ret) - ret = -EPIPE; - goto out_unlock; - } - if (pipe->nrbufs + cs.nr_segs > pipe->buffers) { ret = -EIO; - goto out_unlock; + goto out; } - while (page_nr < cs.nr_segs) { - int newbuf = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1); - struct pipe_buffer *buf = pipe->bufs + newbuf; - - buf->page = bufs[page_nr].page; - buf->offset = bufs[page_nr].offset; - buf->len = bufs[page_nr].len; + for (ret = total = 0; page_nr < cs.nr_segs; total += ret) { /* * Need to be careful about this. Having buf->ops in module * code can Oops if the buffer persists after module unload. */ - buf->ops = &nosteal_pipe_buf_ops; - - pipe->nrbufs++; - page_nr++; - ret += buf->len; - - if (pipe->files) - do_wakeup = 1; - } - -out_unlock: - pipe_unlock(pipe); - - if (do_wakeup) { - smp_mb(); - if (waitqueue_active(&pipe->wait)) - wake_up_interruptible(&pipe->wait); - kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN); + bufs[page_nr].ops = &nosteal_pipe_buf_ops; + ret = add_to_pipe(pipe, &bufs[page_nr++]); + if (unlikely(ret < 0)) + break; } - + if (total) + ret = total; out: for (; page_nr < cs.nr_segs; page_nr++) put_page(bufs[page_nr].page); @@ -1992,7 +1962,7 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe, pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1); pipe->nrbufs--; } else { - ibuf->ops->get(pipe, ibuf); + pipe_buf_get(pipe, ibuf); *obuf = *ibuf; obuf->flags &= ~PIPE_BUF_FLAG_GIFT; obuf->len = rem; @@ -2014,10 +1984,9 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe, ret = fuse_dev_do_write(fud, &cs, len); - for (idx = 0; idx < nbuf; idx++) { - struct pipe_buffer *buf = &bufs[idx]; - buf->ops->release(pipe, buf); - } + for (idx = 0; idx < nbuf; idx++) + pipe_buf_release(pipe, &bufs[idx]); + out: kfree(bufs); return ret; diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c index 360188f162bd..e23ff70b3435 100644 --- a/fs/gfs2/file.c +++ b/fs/gfs2/file.c @@ -954,30 +954,6 @@ out_uninit: return ret; } -static ssize_t gfs2_file_splice_read(struct file *in, loff_t *ppos, - struct pipe_inode_info *pipe, size_t len, - unsigned int flags) -{ - struct inode *inode = in->f_mapping->host; - struct gfs2_inode *ip = GFS2_I(inode); - struct gfs2_holder gh; - int ret; - - inode_lock(inode); - - ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh); - if (ret) { - inode_unlock(inode); - return ret; - } - - gfs2_glock_dq_uninit(&gh); - inode_unlock(inode); - - return generic_file_splice_read(in, ppos, pipe, len, flags); -} - - static ssize_t gfs2_file_splice_write(struct pipe_inode_info *pipe, struct file *out, loff_t *ppos, size_t len, unsigned int flags) @@ -1140,7 +1116,7 @@ const struct file_operations gfs2_file_fops = { .fsync = gfs2_fsync, .lock = gfs2_lock, .flock = gfs2_flock, - .splice_read = gfs2_file_splice_read, + .splice_read = generic_file_splice_read, .splice_write = gfs2_file_splice_write, .setlease = simple_nosetlease, .fallocate = gfs2_fallocate, @@ -1168,7 +1144,7 @@ const struct file_operations gfs2_file_fops_nolock = { .open = gfs2_open, .release = gfs2_release, .fsync = gfs2_fsync, - .splice_read = gfs2_file_splice_read, + .splice_read = generic_file_splice_read, .splice_write = gfs2_file_splice_write, .setlease = generic_setlease, .fallocate = gfs2_fallocate, diff --git a/fs/nfs/file.c b/fs/nfs/file.c index ca699ddc11c1..2efbdde36c3e 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -182,29 +182,6 @@ nfs_file_read(struct kiocb *iocb, struct iov_iter *to) } EXPORT_SYMBOL_GPL(nfs_file_read); -ssize_t -nfs_file_splice_read(struct file *filp, loff_t *ppos, - struct pipe_inode_info *pipe, size_t count, - unsigned int flags) -{ - struct inode *inode = file_inode(filp); - ssize_t res; - - dprintk("NFS: splice_read(%pD2, %lu@%Lu)\n", - filp, (unsigned long) count, (unsigned long long) *ppos); - - nfs_start_io_read(inode); - res = nfs_revalidate_mapping(inode, filp->f_mapping); - if (!res) { - res = generic_file_splice_read(filp, ppos, pipe, count, flags); - if (res > 0) - nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, res); - } - nfs_end_io_read(inode); - return res; -} -EXPORT_SYMBOL_GPL(nfs_file_splice_read); - int nfs_file_mmap(struct file * file, struct vm_area_struct * vma) { @@ -871,7 +848,7 @@ const struct file_operations nfs_file_operations = { .fsync = nfs_file_fsync, .lock = nfs_lock, .flock = nfs_flock, - .splice_read = nfs_file_splice_read, + .splice_read = generic_file_splice_read, .splice_write = iter_file_splice_write, .check_flags = nfs_check_flags, .setlease = simple_nosetlease, diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h index 74935a19e4bf..d7b062bdc504 100644 --- a/fs/nfs/internal.h +++ b/fs/nfs/internal.h @@ -365,8 +365,6 @@ int nfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *) int nfs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync); loff_t nfs_file_llseek(struct file *, loff_t, int); ssize_t nfs_file_read(struct kiocb *, struct iov_iter *); -ssize_t nfs_file_splice_read(struct file *, loff_t *, struct pipe_inode_info *, - size_t, unsigned int); int nfs_file_mmap(struct file *, struct vm_area_struct *); ssize_t nfs_file_write(struct kiocb *, struct iov_iter *); int nfs_file_release(struct inode *, struct file *); diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c index d085ad794884..89a77950e0b0 100644 --- a/fs/nfs/nfs4file.c +++ b/fs/nfs/nfs4file.c @@ -248,7 +248,7 @@ const struct file_operations nfs4_file_operations = { .fsync = nfs_file_fsync, .lock = nfs_lock, .flock = nfs_flock, - .splice_read = nfs_file_splice_read, + .splice_read = generic_file_splice_read, .splice_write = iter_file_splice_write, .check_flags = nfs_check_flags, .setlease = simple_nosetlease, diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c index 0b055bfb8e86..8f91639f8364 100644 --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -2321,36 +2321,6 @@ out_mutex: return ret; } -static ssize_t ocfs2_file_splice_read(struct file *in, - loff_t *ppos, - struct pipe_inode_info *pipe, - size_t len, - unsigned int flags) -{ - int ret = 0, lock_level = 0; - struct inode *inode = file_inode(in); - - trace_ocfs2_file_splice_read(inode, in, in->f_path.dentry, - (unsigned long long)OCFS2_I(inode)->ip_blkno, - in->f_path.dentry->d_name.len, - in->f_path.dentry->d_name.name, len); - - /* - * See the comment in ocfs2_file_read_iter() - */ - ret = ocfs2_inode_lock_atime(inode, in->f_path.mnt, &lock_level); - if (ret < 0) { - mlog_errno(ret); - goto bail; - } - ocfs2_inode_unlock(inode, lock_level); - - ret = generic_file_splice_read(in, ppos, pipe, len, flags); - -bail: - return ret; -} - static ssize_t ocfs2_file_read_iter(struct kiocb *iocb, struct iov_iter *to) { @@ -2509,7 +2479,7 @@ const struct file_operations ocfs2_fops = { #endif .lock = ocfs2_lock, .flock = ocfs2_flock, - .splice_read = ocfs2_file_splice_read, + .splice_read = generic_file_splice_read, .splice_write = iter_file_splice_write, .fallocate = ocfs2_fallocate, }; @@ -2554,7 +2524,7 @@ const struct file_operations ocfs2_fops_no_plocks = { .compat_ioctl = ocfs2_compat_ioctl, #endif .flock = ocfs2_flock, - .splice_read = ocfs2_file_splice_read, + .splice_read = generic_file_splice_read, .splice_write = iter_file_splice_write, .fallocate = ocfs2_fallocate, }; diff --git a/fs/ocfs2/ocfs2_trace.h b/fs/ocfs2/ocfs2_trace.h index f8f5fc5e6c05..0b58abcf1c6d 100644 --- a/fs/ocfs2/ocfs2_trace.h +++ b/fs/ocfs2/ocfs2_trace.h @@ -1314,8 +1314,6 @@ DEFINE_OCFS2_FILE_OPS(ocfs2_file_aio_write); DEFINE_OCFS2_FILE_OPS(ocfs2_file_splice_write); -DEFINE_OCFS2_FILE_OPS(ocfs2_file_splice_read); - DEFINE_OCFS2_FILE_OPS(ocfs2_file_aio_read); DEFINE_OCFS2_ULL_ULL_ULL_EVENT(ocfs2_truncate_file); diff --git a/fs/pipe.c b/fs/pipe.c index 4ebe6b2e5217..4fc422f0dea8 100644 --- a/fs/pipe.c +++ b/fs/pipe.c @@ -267,7 +267,6 @@ pipe_read(struct kiocb *iocb, struct iov_iter *to) if (bufs) { int curbuf = pipe->curbuf; struct pipe_buffer *buf = pipe->bufs + curbuf; - const struct pipe_buf_operations *ops = buf->ops; size_t chars = buf->len; size_t written; int error; @@ -275,7 +274,7 @@ pipe_read(struct kiocb *iocb, struct iov_iter *to) if (chars > total_len) chars = total_len; - error = ops->confirm(pipe, buf); + error = pipe_buf_confirm(pipe, buf); if (error) { if (!ret) ret = error; @@ -299,8 +298,7 @@ pipe_read(struct kiocb *iocb, struct iov_iter *to) } if (!buf->len) { - buf->ops = NULL; - ops->release(pipe, buf); + pipe_buf_release(pipe, buf); curbuf = (curbuf + 1) & (pipe->buffers - 1); pipe->curbuf = curbuf; pipe->nrbufs = --bufs; @@ -383,11 +381,10 @@ pipe_write(struct kiocb *iocb, struct iov_iter *from) int lastbuf = (pipe->curbuf + pipe->nrbufs - 1) & (pipe->buffers - 1); struct pipe_buffer *buf = pipe->bufs + lastbuf; - const struct pipe_buf_operations *ops = buf->ops; int offset = buf->offset + buf->len; - if (ops->can_merge && offset + chars <= PAGE_SIZE) { - ret = ops->confirm(pipe, buf); + if (buf->ops->can_merge && offset + chars <= PAGE_SIZE) { + ret = pipe_buf_confirm(pipe, buf); if (ret) goto out; @@ -664,7 +661,7 @@ void free_pipe_info(struct pipe_inode_info *pipe) for (i = 0; i < pipe->buffers; i++) { struct pipe_buffer *buf = pipe->bufs + i; if (buf->ops) - buf->ops->release(pipe, buf); + pipe_buf_release(pipe, buf); } if (pipe->tmp_page) __free_page(pipe->tmp_page); diff --git a/fs/splice.c b/fs/splice.c index dd9bf7e410d2..aa38901a4f10 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -183,82 +183,39 @@ ssize_t splice_to_pipe(struct pipe_inode_info *pipe, struct splice_pipe_desc *spd) { unsigned int spd_pages = spd->nr_pages; - int ret, do_wakeup, page_nr; + int ret = 0, page_nr = 0; if (!spd_pages) return 0; - ret = 0; - do_wakeup = 0; - page_nr = 0; - - pipe_lock(pipe); - - for (;;) { - if (!pipe->readers) { - send_sig(SIGPIPE, current, 0); - if (!ret) - ret = -EPIPE; - break; - } - - if (pipe->nrbufs < pipe->buffers) { - int newbuf = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1); - struct pipe_buffer *buf = pipe->bufs + newbuf; - - 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; - if (spd->flags & SPLICE_F_GIFT) - buf->flags |= PIPE_BUF_FLAG_GIFT; - - pipe->nrbufs++; - page_nr++; - ret += buf->len; - - if (pipe->files) - do_wakeup = 1; + if (unlikely(!pipe->readers)) { + send_sig(SIGPIPE, current, 0); + ret = -EPIPE; + goto out; + } - if (!--spd->nr_pages) - break; - if (pipe->nrbufs < pipe->buffers) - continue; + while (pipe->nrbufs < pipe->buffers) { + int newbuf = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1); + struct pipe_buffer *buf = pipe->bufs + newbuf; - break; - } + 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; - if (spd->flags & SPLICE_F_NONBLOCK) { - if (!ret) - ret = -EAGAIN; - break; - } + pipe->nrbufs++; + page_nr++; + ret += buf->len; - if (signal_pending(current)) { - if (!ret) - ret = -ERESTARTSYS; + if (!--spd->nr_pages) break; - } - - if (do_wakeup) { - smp_mb(); - if (waitqueue_active(&pipe->wait)) - wake_up_interruptible_sync(&pipe->wait); - kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN); - do_wakeup = 0; - } - - pipe->waiting_writers++; - pipe_wait(pipe); - pipe->waiting_writers--; } - pipe_unlock(pipe); - - if (do_wakeup) - wakeup_pipe_readers(pipe); + if (!ret) + ret = -EAGAIN; +out: while (page_nr < spd_pages) spd->spd_release(spd, page_nr++); @@ -266,6 +223,26 @@ ssize_t splice_to_pipe(struct pipe_inode_info *pipe, } EXPORT_SYMBOL_GPL(splice_to_pipe); +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; + } + pipe_buf_release(pipe, buf); + return ret; +} +EXPORT_SYMBOL(add_to_pipe); + void spd_release_page(struct splice_pipe_desc *spd, unsigned int i) { put_page(spd->pages[i]); @@ -303,207 +280,6 @@ void splice_shrink_spd(struct splice_pipe_desc *spd) kfree(spd->partial); } -static int -__generic_file_splice_read(struct file *in, loff_t *ppos, - struct pipe_inode_info *pipe, size_t len, - unsigned int flags) -{ - struct address_space *mapping = in->f_mapping; - unsigned int loff, nr_pages, req_pages; - struct page *pages[PIPE_DEF_BUFFERS]; - struct partial_page partial[PIPE_DEF_BUFFERS]; - struct page *page; - pgoff_t index, end_index; - loff_t isize; - int error, page_nr; - struct splice_pipe_desc spd = { - .pages = pages, - .partial = partial, - .nr_pages_max = PIPE_DEF_BUFFERS, - .flags = flags, - .ops = &page_cache_pipe_buf_ops, - .spd_release = spd_release_page, - }; - - if (splice_grow_spd(pipe, &spd)) - return -ENOMEM; - - index = *ppos >> PAGE_SHIFT; - loff = *ppos & ~PAGE_MASK; - req_pages = (len + loff + PAGE_SIZE - 1) >> PAGE_SHIFT; - nr_pages = min(req_pages, spd.nr_pages_max); - - /* - * Lookup the (hopefully) full range of pages we need. - */ - spd.nr_pages = find_get_pages_contig(mapping, index, nr_pages, spd.pages); - index += spd.nr_pages; - - /* - * If find_get_pages_contig() returned fewer pages than we needed, - * readahead/allocate the rest and fill in the holes. - */ - if (spd.nr_pages < nr_pages) - page_cache_sync_readahead(mapping, &in->f_ra, in, - index, req_pages - spd.nr_pages); - - error = 0; - while (spd.nr_pages < nr_pages) { - /* - * Page could be there, find_get_pages_contig() breaks on - * the first hole. - */ - page = find_get_page(mapping, index); - if (!page) { - /* - * page didn't exist, allocate one. - */ - page = page_cache_alloc_cold(mapping); - if (!page) - break; - - error = add_to_page_cache_lru(page, mapping, index, - mapping_gfp_constraint(mapping, GFP_KERNEL)); - if (unlikely(error)) { - put_page(page); - if (error == -EEXIST) - continue; - break; - } - /* - * add_to_page_cache() locks the page, unlock it - * to avoid convoluting the logic below even more. - */ - unlock_page(page); - } - - spd.pages[spd.nr_pages++] = page; - index++; - } - - /* - * Now loop over the map and see if we need to start IO on any - * pages, fill in the partial map, etc. - */ - index = *ppos >> PAGE_SHIFT; - nr_pages = spd.nr_pages; - spd.nr_pages = 0; - for (page_nr = 0; page_nr < nr_pages; page_nr++) { - unsigned int this_len; - - if (!len) - break; - - /* - * this_len is the max we'll use from this page - */ - this_len = min_t(unsigned long, len, PAGE_SIZE - loff); - page = spd.pages[page_nr]; - - if (PageReadahead(page)) - page_cache_async_readahead(mapping, &in->f_ra, in, - page, index, req_pages - page_nr); - - /* - * If the page isn't uptodate, we may need to start io on it - */ - if (!PageUptodate(page)) { - lock_page(page); - - /* - * Page was truncated, or invalidated by the - * filesystem. Redo the find/create, but this time the - * page is kept locked, so there's no chance of another - * race with truncate/invalidate. - */ - if (!page->mapping) { - unlock_page(page); -retry_lookup: - page = find_or_create_page(mapping, index, - mapping_gfp_mask(mapping)); - - if (!page) { - error = -ENOMEM; - break; - } - put_page(spd.pages[page_nr]); - spd.pages[page_nr] = page; - } - /* - * page was already under io and is now done, great - */ - if (PageUptodate(page)) { - unlock_page(page); - goto fill_it; - } - - /* - * need to read in the page - */ - error = mapping->a_ops->readpage(in, page); - if (unlikely(error)) { - /* - * Re-lookup the page - */ - if (error == AOP_TRUNCATED_PAGE) - goto retry_lookup; - - break; - } - } -fill_it: - /* - * i_size must be checked after PageUptodate. - */ - isize = i_size_read(mapping->host); - end_index = (isize - 1) >> PAGE_SHIFT; - if (unlikely(!isize || index > end_index)) - break; - - /* - * if this is the last page, see if we need to shrink - * the length and stop - */ - if (end_index == index) { - unsigned int plen; - - /* - * max good bytes in this page - */ - plen = ((isize - 1) & ~PAGE_MASK) + 1; - if (plen <= loff) - break; - - /* - * force quit after adding this page - */ - this_len = min(this_len, plen - loff); - len = this_len; - } - - spd.partial[page_nr].offset = loff; - spd.partial[page_nr].len = this_len; - len -= this_len; - loff = 0; - spd.nr_pages++; - index++; - } - - /* - * Release any pages at the end, if we quit early. 'page_nr' is how far - * we got, 'nr_pages' is how many pages are in the map. - */ - while (page_nr < nr_pages) - put_page(spd.pages[page_nr++]); - in->f_ra.prev_pos = (loff_t)index << PAGE_SHIFT; - - if (spd.nr_pages) - error = splice_to_pipe(pipe, &spd); - - splice_shrink_spd(&spd); - return error; -} - /** * generic_file_splice_read - splice data from file to a pipe * @in: file to splice from @@ -514,39 +290,53 @@ fill_it: * * Description: * Will read pages from given file and fill them into a pipe. Can be - * used as long as the address_space operations for the source implements - * a readpage() hook. + * used as long as it has more or less sane ->read_iter(). * */ ssize_t generic_file_splice_read(struct file *in, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags) { - loff_t isize, left; - int ret; - - if (IS_DAX(in->f_mapping->host)) - return default_file_splice_read(in, ppos, pipe, len, flags); + struct iov_iter to; + struct kiocb kiocb; + loff_t isize; + int idx, ret; isize = i_size_read(in->f_mapping->host); if (unlikely(*ppos >= isize)) return 0; - left = isize - *ppos; - if (unlikely(left < len)) - len = left; - - ret = __generic_file_splice_read(in, ppos, pipe, len, flags); + iov_iter_pipe(&to, ITER_PIPE | READ, pipe, len); + idx = to.idx; + init_sync_kiocb(&kiocb, in); + kiocb.ki_pos = *ppos; + ret = in->f_op->read_iter(&kiocb, &to); if (ret > 0) { - *ppos += ret; + *ppos = kiocb.ki_pos; file_accessed(in); + } else if (ret < 0) { + if (WARN_ON(to.idx != idx || to.iov_offset)) { + /* + * a bogus ->read_iter() has copied something and still + * returned an error instead of a short read. + */ + to.idx = idx; + to.iov_offset = 0; + iov_iter_advance(&to, 0); /* to free what was emitted */ + } + /* + * callers of ->splice_read() expect -EAGAIN on + * "can't put anything in there", rather than -EFAULT. + */ + if (ret == -EFAULT) + ret = -EAGAIN; } return ret; } EXPORT_SYMBOL(generic_file_splice_read); -static const struct pipe_buf_operations default_pipe_buf_ops = { +const struct pipe_buf_operations default_pipe_buf_ops = { .can_merge = 0, .confirm = generic_pipe_buf_confirm, .release = generic_pipe_buf_release, @@ -570,7 +360,7 @@ const struct pipe_buf_operations nosteal_pipe_buf_ops = { }; EXPORT_SYMBOL(nosteal_pipe_buf_ops); -static ssize_t kernel_readv(struct file *file, const struct iovec *vec, +static ssize_t kernel_readv(struct file *file, const struct kvec *vec, unsigned long vlen, loff_t offset) { mm_segment_t old_fs; @@ -602,102 +392,70 @@ ssize_t kernel_write(struct file *file, const char *buf, size_t count, } EXPORT_SYMBOL(kernel_write); -ssize_t default_file_splice_read(struct file *in, loff_t *ppos, +static ssize_t default_file_splice_read(struct file *in, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags) { + struct kvec *vec, __vec[PIPE_DEF_BUFFERS]; + struct iov_iter to; + struct page **pages; unsigned int nr_pages; - unsigned int nr_freed; - size_t offset; - struct page *pages[PIPE_DEF_BUFFERS]; - struct partial_page partial[PIPE_DEF_BUFFERS]; - struct iovec *vec, __vec[PIPE_DEF_BUFFERS]; + size_t offset, dummy, copied = 0; ssize_t res; - size_t this_len; - int error; int i; - struct splice_pipe_desc spd = { - .pages = pages, - .partial = partial, - .nr_pages_max = PIPE_DEF_BUFFERS, - .flags = flags, - .ops = &default_pipe_buf_ops, - .spd_release = spd_release_page, - }; - if (splice_grow_spd(pipe, &spd)) + if (pipe->nrbufs == pipe->buffers) + return -EAGAIN; + + /* + * Try to keep page boundaries matching to source pagecache ones - + * it probably won't be much help, but... + */ + offset = *ppos & ~PAGE_MASK; + + iov_iter_pipe(&to, ITER_PIPE | READ, pipe, len + offset); + + res = iov_iter_get_pages_alloc(&to, &pages, len + offset, &dummy); + if (res <= 0) return -ENOMEM; - res = -ENOMEM; + nr_pages = res / PAGE_SIZE; + vec = __vec; - if (spd.nr_pages_max > PIPE_DEF_BUFFERS) { - vec = kmalloc(spd.nr_pages_max * sizeof(struct iovec), GFP_KERNEL); - if (!vec) - goto shrink_ret; + if (nr_pages > PIPE_DEF_BUFFERS) { + vec = kmalloc(nr_pages * sizeof(struct kvec), GFP_KERNEL); + if (unlikely(!vec)) { + res = -ENOMEM; + goto out; + } } - offset = *ppos & ~PAGE_MASK; - nr_pages = (len + offset + PAGE_SIZE - 1) >> PAGE_SHIFT; - - for (i = 0; i < nr_pages && i < spd.nr_pages_max && len; i++) { - struct page *page; + pipe->bufs[to.idx].offset = offset; + pipe->bufs[to.idx].len -= offset; - page = alloc_page(GFP_USER); - error = -ENOMEM; - if (!page) - goto err; - - this_len = min_t(size_t, len, PAGE_SIZE - offset); - vec[i].iov_base = (void __user *) page_address(page); + 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; - spd.pages[i] = page; - spd.nr_pages++; len -= this_len; offset = 0; } - res = kernel_readv(in, vec, spd.nr_pages, *ppos); - if (res < 0) { - error = res; - goto err; - } - - error = 0; - if (!res) - goto err; - - nr_freed = 0; - for (i = 0; i < spd.nr_pages; i++) { - this_len = min_t(size_t, vec[i].iov_len, res); - spd.partial[i].offset = 0; - spd.partial[i].len = this_len; - if (!this_len) { - __free_page(spd.pages[i]); - spd.pages[i] = NULL; - nr_freed++; - } - res -= this_len; - } - spd.nr_pages -= nr_freed; - - res = splice_to_pipe(pipe, &spd); - if (res > 0) + res = kernel_readv(in, vec, nr_pages, *ppos); + if (res > 0) { + copied = res; *ppos += res; + } -shrink_ret: if (vec != __vec) kfree(vec); - splice_shrink_spd(&spd); +out: + for (i = 0; i < nr_pages; i++) + put_page(pages[i]); + kvfree(pages); + iov_iter_advance(&to, copied); /* truncates and discards */ return res; - -err: - for (i = 0; i < spd.nr_pages; i++) - __free_page(spd.pages[i]); - - res = error; - goto shrink_ret; } -EXPORT_SYMBOL(default_file_splice_read); /* * Send 'sd->len' bytes to socket from 'sd->file' at position 'sd->pos' @@ -757,13 +515,12 @@ static int splice_from_pipe_feed(struct pipe_inode_info *pipe, struct splice_des while (pipe->nrbufs) { struct pipe_buffer *buf = pipe->bufs + pipe->curbuf; - const struct pipe_buf_operations *ops = buf->ops; sd->len = buf->len; if (sd->len > sd->total_len) sd->len = sd->total_len; - ret = buf->ops->confirm(pipe, buf); + ret = pipe_buf_confirm(pipe, buf); if (unlikely(ret)) { if (ret == -ENODATA) ret = 0; @@ -783,8 +540,7 @@ static int splice_from_pipe_feed(struct pipe_inode_info *pipe, struct splice_des sd->total_len -= ret; if (!buf->len) { - buf->ops = NULL; - ops->release(pipe, buf); + pipe_buf_release(pipe, buf); pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1); pipe->nrbufs--; if (pipe->files) @@ -1003,7 +759,7 @@ iter_file_splice_write(struct pipe_inode_info *pipe, struct file *out, if (idx == pipe->buffers - 1) idx = -1; - ret = buf->ops->confirm(pipe, buf); + ret = pipe_buf_confirm(pipe, buf); if (unlikely(ret)) { if (ret == -ENODATA) ret = 0; @@ -1030,11 +786,9 @@ iter_file_splice_write(struct pipe_inode_info *pipe, struct file *out, while (ret) { struct pipe_buffer *buf = pipe->bufs + pipe->curbuf; if (ret >= buf->len) { - const struct pipe_buf_operations *ops = buf->ops; ret -= buf->len; buf->len = 0; - buf->ops = NULL; - ops->release(pipe, buf); + pipe_buf_release(pipe, buf); pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1); pipe->nrbufs--; if (pipe->files) @@ -1273,10 +1027,8 @@ out_release: for (i = 0; i < pipe->buffers; i++) { struct pipe_buffer *buf = pipe->bufs + i; - if (buf->ops) { - buf->ops->release(pipe, buf); - buf->ops = NULL; - } + if (buf->ops) + pipe_buf_release(pipe, buf); } if (!bytes) @@ -1342,6 +1094,20 @@ long do_splice_direct(struct file *in, loff_t *ppos, struct file *out, } EXPORT_SYMBOL(do_splice_direct); +static int wait_for_space(struct pipe_inode_info *pipe, unsigned flags) +{ + while (pipe->nrbufs == pipe->buffers) { + if (flags & SPLICE_F_NONBLOCK) + return -EAGAIN; + if (signal_pending(current)) + return -ERESTARTSYS; + pipe->waiting_writers++; + pipe_wait(pipe); + pipe->waiting_writers--; + } + return 0; +} + static int splice_pipe_to_pipe(struct pipe_inode_info *ipipe, struct pipe_inode_info *opipe, size_t len, unsigned int flags); @@ -1424,8 +1190,13 @@ static long do_splice(struct file *in, loff_t __user *off_in, offset = in->f_pos; } - ret = do_splice_to(in, &offset, opipe, len, flags); - + 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); if (!off_in) in->f_pos = offset; else if (copy_to_user(off_in, &offset, sizeof(loff_t))) @@ -1437,106 +1208,50 @@ static long do_splice(struct file *in, loff_t __user *off_in, return -EINVAL; } -/* - * Map an iov into an array of pages and offset/length tupples. With the - * partial_page structure, we can map several non-contiguous ranges into - * our ones pages[] map instead of splitting that operation into pieces. - * Could easily be exported as a generic helper for other users, in which - * case one would probably want to add a 'max_nr_pages' parameter as well. - */ -static int get_iovec_page_array(const struct iovec __user *iov, - unsigned int nr_vecs, struct page **pages, - struct partial_page *partial, bool aligned, - unsigned int pipe_buffers) +static int iter_to_pipe(struct iov_iter *from, + struct pipe_inode_info *pipe, + unsigned flags) { - int buffers = 0, error = 0; - - while (nr_vecs) { - unsigned long off, npages; - struct iovec entry; - void __user *base; - size_t len; - int i; - - error = -EFAULT; - if (copy_from_user(&entry, iov, sizeof(entry))) - break; - - base = entry.iov_base; - len = entry.iov_len; - - /* - * Sanity check this iovec. 0 read succeeds. - */ - error = 0; - if (unlikely(!len)) - break; - error = -EFAULT; - if (!access_ok(VERIFY_READ, base, len)) - break; - - /* - * Get this base offset and number of pages, then map - * in the user pages. - */ - off = (unsigned long) base & ~PAGE_MASK; - - /* - * If asked for alignment, the offset must be zero and the - * length a multiple of the PAGE_SIZE. - */ - error = -EINVAL; - if (aligned && (off || len & ~PAGE_MASK)) - break; - - npages = (off + len + PAGE_SIZE - 1) >> PAGE_SHIFT; - if (npages > pipe_buffers - buffers) - npages = pipe_buffers - buffers; - - error = get_user_pages_fast((unsigned long)base, npages, - 0, &pages[buffers]); - - if (unlikely(error <= 0)) + 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]; + ssize_t copied; + size_t start; + int n; + + copied = iov_iter_get_pages(from, pages, ~0UL, 16, &start); + if (copied <= 0) { + ret = copied; break; - - /* - * Fill this contiguous range into the partial page map. - */ - for (i = 0; i < error; i++) { - const int plen = min_t(size_t, len, PAGE_SIZE - off); - - partial[buffers].offset = off; - partial[buffers].len = plen; - - off = 0; - len -= plen; - buffers++; } - /* - * We didn't complete this iov, stop here since it probably - * means we have to move some of this into a pipe to - * be able to continue. - */ - if (len) - break; - - /* - * Don't continue if we mapped fewer pages than we asked for, - * or if we mapped the max number of pages that we have - * room for. - */ - if (error < npages || buffers == pipe_buffers) - break; - - nr_vecs--; - iov++; + for (n = 0; copied; n++, start = 0) { + int size = min_t(int, copied, PAGE_SIZE - start); + 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]); + } + copied -= size; + } } - - if (buffers) - return buffers; - - return error; + return total ? total : ret; } static int pipe_to_user(struct pipe_inode_info *pipe, struct pipe_buffer *buf, @@ -1590,38 +1305,36 @@ static long vmsplice_to_user(struct file *file, const struct iovec __user *uiov, * as splice-from-memory, where the regular splice is splice-from-file (or * to file). In both cases the output is a pipe, naturally. */ -static long vmsplice_to_pipe(struct file *file, const struct iovec __user *iov, +static long vmsplice_to_pipe(struct file *file, const struct iovec __user *uiov, unsigned long nr_segs, unsigned int flags) { struct pipe_inode_info *pipe; - struct page *pages[PIPE_DEF_BUFFERS]; - struct partial_page partial[PIPE_DEF_BUFFERS]; - struct splice_pipe_desc spd = { - .pages = pages, - .partial = partial, - .nr_pages_max = PIPE_DEF_BUFFERS, - .flags = flags, - .ops = &user_page_pipe_buf_ops, - .spd_release = spd_release_page, - }; + struct iovec iovstack[UIO_FASTIOV]; + struct iovec *iov = iovstack; + struct iov_iter from; long ret; + unsigned buf_flag = 0; + + if (flags & SPLICE_F_GIFT) + buf_flag = PIPE_BUF_FLAG_GIFT; pipe = get_pipe_info(file); if (!pipe) return -EBADF; - if (splice_grow_spd(pipe, &spd)) - return -ENOMEM; - - spd.nr_pages = get_iovec_page_array(iov, nr_segs, spd.pages, - spd.partial, false, - spd.nr_pages_max); - if (spd.nr_pages <= 0) - ret = spd.nr_pages; - else - ret = splice_to_pipe(pipe, &spd); + ret = import_iovec(WRITE, uiov, nr_segs, + ARRAY_SIZE(iovstack), &iov, &from); + if (ret < 0) + return ret; - splice_shrink_spd(&spd); + pipe_lock(pipe); + ret = wait_for_space(pipe, flags); + if (!ret) + ret = iter_to_pipe(&from, pipe, buf_flag); + pipe_unlock(pipe); + if (ret > 0) + wakeup_pipe_readers(pipe); + kfree(iov); return ret; } @@ -1876,7 +1589,7 @@ retry: * Get a reference to this pipe buffer, * so we can copy the contents over. */ - ibuf->ops->get(ipipe, ibuf); + pipe_buf_get(ipipe, ibuf); *obuf = *ibuf; /* @@ -1948,7 +1661,7 @@ static int link_pipe(struct pipe_inode_info *ipipe, * Get a reference to this pipe buffer, * so we can copy the contents over. */ - ibuf->ops->get(ipipe, ibuf); + pipe_buf_get(ipipe, ibuf); obuf = opipe->bufs + nbuf; *obuf = *ibuf; diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index c68517b0f248..f46b2929c64d 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -393,45 +393,6 @@ xfs_file_read_iter( return ret; } -STATIC ssize_t -xfs_file_splice_read( - struct file *infilp, - loff_t *ppos, - struct pipe_inode_info *pipe, - size_t count, - unsigned int flags) -{ - struct xfs_inode *ip = XFS_I(infilp->f_mapping->host); - ssize_t ret; - - XFS_STATS_INC(ip->i_mount, xs_read_calls); - - if (XFS_FORCED_SHUTDOWN(ip->i_mount)) - return -EIO; - - trace_xfs_file_splice_read(ip, count, *ppos); - - /* - * DAX inodes cannot ues the page cache for splice, so we have to push - * them through the VFS IO path. This means it goes through - * ->read_iter, which for us takes the XFS_IOLOCK_SHARED. Hence we - * cannot lock the splice operation at this level for DAX inodes. - */ - if (IS_DAX(VFS_I(ip))) { - ret = default_file_splice_read(infilp, ppos, pipe, count, - flags); - goto out; - } - - xfs_rw_ilock(ip, XFS_IOLOCK_SHARED); - ret = generic_file_splice_read(infilp, ppos, pipe, count, flags); - xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED); -out: - if (ret > 0) - XFS_STATS_ADD(ip->i_mount, xs_read_bytes, ret); - return ret; -} - /* * Zero any on disk space between the current EOF and the new, larger EOF. * @@ -1608,7 +1569,7 @@ const struct file_operations xfs_file_operations = { .llseek = xfs_file_llseek, .read_iter = xfs_file_read_iter, .write_iter = xfs_file_write_iter, - .splice_read = xfs_file_splice_read, + .splice_read = generic_file_splice_read, .splice_write = iter_file_splice_write, .unlocked_ioctl = xfs_file_ioctl, #ifdef CONFIG_COMPAT diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h index c6b2b1dcde75..16093c7dacde 100644 --- a/fs/xfs/xfs_trace.h +++ b/fs/xfs/xfs_trace.h @@ -1170,7 +1170,6 @@ DEFINE_RW_EVENT(xfs_file_dax_read); DEFINE_RW_EVENT(xfs_file_buffered_write); DEFINE_RW_EVENT(xfs_file_direct_write); DEFINE_RW_EVENT(xfs_file_dax_write); -DEFINE_RW_EVENT(xfs_file_splice_read); DECLARE_EVENT_CLASS(xfs_page_class, TP_PROTO(struct inode *inode, struct page *page, unsigned long off, |