From c37222082f23c456664d1c3182a714670ab8f9a4 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:49:48 +0100 Subject: splice: Fix filemap_splice_read() to use the correct inode Fix filemap_splice_read() to use file->f_mapping->host, not file->f_inode, as the source of the file size because in the case of a block device, file->f_inode points to the block-special file (which is typically 0 length) and not the backing store. Fixes: 07073eb01c5f ("splice: Add a func to do a splice from a buffered file without ITER_PIPE") Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: Christian Brauner cc: Steve French cc: Jens Axboe cc: Al Viro cc: David Hildenbrand cc: John Hubbard cc: linux-mm@kvack.org cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20230522135018.2742245-2-dhowells@redhat.com Signed-off-by: Jens Axboe --- mm/filemap.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/filemap.c b/mm/filemap.c index b4c9bd368b7e..a2006936a6ae 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2900,7 +2900,7 @@ ssize_t filemap_splice_read(struct file *in, loff_t *ppos, do { cond_resched(); - if (*ppos >= i_size_read(file_inode(in))) + if (*ppos >= i_size_read(in->f_mapping->host)) break; iocb.ki_pos = *ppos; @@ -2916,7 +2916,7 @@ ssize_t filemap_splice_read(struct file *in, loff_t *ppos, * part of the page is not copied back to userspace (unless * another truncate extends the file - this is desired though). */ - isize = i_size_read(file_inode(in)); + isize = i_size_read(in->f_mapping->host); if (unlikely(*ppos >= isize)) break; end_offset = min_t(loff_t, isize, *ppos + len); -- cgit v1.2.3-70-g09d2 From 83aeff881e53fab5b46e4ceb5fb47fa0a22acba9 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:49:49 +0100 Subject: splice: Make filemap_splice_read() check s_maxbytes Make filemap_splice_read() check s_maxbytes analogously to filemap_read(). Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: Christian Brauner cc: Steve French cc: Jens Axboe cc: Al Viro cc: David Hildenbrand cc: John Hubbard cc: linux-mm@kvack.org cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20230522135018.2742245-3-dhowells@redhat.com Signed-off-by: Jens Axboe --- mm/filemap.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/filemap.c b/mm/filemap.c index a2006936a6ae..0fcb0b80c2e2 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2887,6 +2887,9 @@ ssize_t filemap_splice_read(struct file *in, loff_t *ppos, bool writably_mapped; int i, error = 0; + if (unlikely(*ppos >= in->f_mapping->host->i_sb->s_maxbytes)) + return 0; + init_sync_kiocb(&iocb, in); iocb.ki_pos = *ppos; -- cgit v1.2.3-70-g09d2 From 69df79a4511117f377d6a5909b47bd4fb541b978 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:49:50 +0100 Subject: splice: Rename direct_splice_read() to copy_splice_read() Rename direct_splice_read() to copy_splice_read() to better reflect as to what it does. Suggested-by: Christoph Hellwig Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: Christian Brauner cc: Steve French cc: Jens Axboe cc: Al Viro cc: linux-cifs@vger.kernel.org cc: linux-mm@kvack.org cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20230522135018.2742245-4-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/cifs/cifsfs.c | 4 ++-- fs/cifs/file.c | 2 +- fs/splice.c | 11 +++++------ include/linux/fs.h | 6 +++--- 4 files changed, 11 insertions(+), 12 deletions(-) diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index 43a4d8603db3..fa2477bbcc86 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -1416,7 +1416,7 @@ const struct file_operations cifs_file_direct_ops = { .fsync = cifs_fsync, .flush = cifs_flush, .mmap = cifs_file_mmap, - .splice_read = direct_splice_read, + .splice_read = copy_splice_read, .splice_write = iter_file_splice_write, .unlocked_ioctl = cifs_ioctl, .copy_file_range = cifs_copy_file_range, @@ -1470,7 +1470,7 @@ const struct file_operations cifs_file_direct_nobrl_ops = { .fsync = cifs_fsync, .flush = cifs_flush, .mmap = cifs_file_mmap, - .splice_read = direct_splice_read, + .splice_read = copy_splice_read, .splice_write = iter_file_splice_write, .unlocked_ioctl = cifs_ioctl, .copy_file_range = cifs_copy_file_range, diff --git a/fs/cifs/file.c b/fs/cifs/file.c index c5fcefdfd797..023496207c18 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -5091,6 +5091,6 @@ ssize_t cifs_splice_read(struct file *in, loff_t *ppos, if (unlikely(!len)) return 0; if (in->f_flags & O_DIRECT) - return direct_splice_read(in, ppos, pipe, len, flags); + return copy_splice_read(in, ppos, pipe, len, flags); return filemap_splice_read(in, ppos, pipe, len, flags); } diff --git a/fs/splice.c b/fs/splice.c index 3e06611d19ae..2478e065bc53 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -300,12 +300,11 @@ void splice_shrink_spd(struct splice_pipe_desc *spd) } /* - * Splice data from an O_DIRECT file into pages and then add them to the output - * pipe. + * Copy data from a file into pages and then splice those into the output pipe. */ -ssize_t direct_splice_read(struct file *in, loff_t *ppos, - struct pipe_inode_info *pipe, - size_t len, unsigned int flags) +ssize_t copy_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, + size_t len, unsigned int flags) { struct iov_iter to; struct bio_vec *bv; @@ -390,7 +389,7 @@ ssize_t direct_splice_read(struct file *in, loff_t *ppos, kfree(bv); return ret; } -EXPORT_SYMBOL(direct_splice_read); +EXPORT_SYMBOL(copy_splice_read); /** * generic_file_splice_read - splice data from file to a pipe diff --git a/include/linux/fs.h b/include/linux/fs.h index 21a981680856..e3c22efa413e 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2752,9 +2752,9 @@ ssize_t vfs_iocb_iter_write(struct file *file, struct kiocb *iocb, ssize_t filemap_splice_read(struct file *in, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags); -ssize_t direct_splice_read(struct file *in, loff_t *ppos, - struct pipe_inode_info *pipe, - size_t len, unsigned int flags); +ssize_t copy_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, + size_t len, unsigned int flags); extern ssize_t generic_file_splice_read(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int); extern ssize_t iter_file_splice_write(struct pipe_inode_info *, -- cgit v1.2.3-70-g09d2 From e69f37bce1b412161e11715adde30dadba0268a2 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:49:51 +0100 Subject: splice: Clean up copy_splice_read() a bit Do a couple of cleanups to copy_splice_read(): (1) Cast to struct page **, not void *. (2) Simplify the calculation of the number of pages to keep/reclaim in copy_splice_read(). Suggested-by: Christoph Hellwig Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: Christian Brauner cc: Jens Axboe cc: Al Viro cc: David Hildenbrand cc: John Hubbard cc: linux-mm@kvack.org cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20230522135018.2742245-5-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/splice.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) diff --git a/fs/splice.c b/fs/splice.c index 2478e065bc53..f9a9be797b0c 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -311,7 +311,7 @@ ssize_t copy_splice_read(struct file *in, loff_t *ppos, struct kiocb kiocb; struct page **pages; ssize_t ret; - size_t used, npages, chunk, remain, reclaim; + size_t used, npages, chunk, remain, keep = 0; int i; /* Work out how much data we can actually add into the pipe */ @@ -325,7 +325,7 @@ ssize_t copy_splice_read(struct file *in, loff_t *ppos, if (!bv) return -ENOMEM; - pages = (void *)(bv + npages); + pages = (struct page **)(bv + npages); npages = alloc_pages_bulk_array(GFP_USER, npages, pages); if (!npages) { kfree(bv); @@ -348,11 +348,8 @@ ssize_t copy_splice_read(struct file *in, loff_t *ppos, kiocb.ki_pos = *ppos; ret = call_read_iter(in, &kiocb, &to); - reclaim = npages * PAGE_SIZE; - remain = 0; if (ret > 0) { - reclaim -= ret; - remain = ret; + keep = DIV_ROUND_UP(ret, PAGE_SIZE); *ppos = kiocb.ki_pos; file_accessed(in); } else if (ret < 0) { @@ -365,14 +362,12 @@ ssize_t copy_splice_read(struct file *in, loff_t *ppos, } /* Free any pages that didn't get touched at all. */ - reclaim /= PAGE_SIZE; - if (reclaim) { - npages -= reclaim; - release_pages(pages + npages, reclaim); - } + if (keep < npages) + release_pages(pages + keep, npages - keep); /* Push the remaining pages into the pipe. */ - for (i = 0; i < npages; i++) { + remain = ret; + for (i = 0; i < keep; i++) { struct pipe_buffer *buf = pipe_head_buf(pipe); chunk = min_t(size_t, remain, PAGE_SIZE); -- cgit v1.2.3-70-g09d2 From 6a3f30b8bdb23842aff5eea65b6a7693c49f5506 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:49:52 +0100 Subject: splice: Make do_splice_to() generic and export it Rename do_splice_to() to vfs_splice_read() and export it so that it can be used as a helper when calling down to a lower layer filesystem as it performs all the necessary checks[1]. Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: Christian Brauner cc: Miklos Szeredi cc: Jens Axboe cc: Al Viro cc: John Hubbard cc: David Hildenbrand cc: Matthew Wilcox cc: linux-unionfs@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/CAJfpeguGksS3sCigmRi9hJdUec8qtM9f+_9jC1rJhsXT+dV01w@mail.gmail.com/ [1] Link: https://lore.kernel.org/r/20230522135018.2742245-6-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/splice.c | 27 ++++++++++++++++++++------- include/linux/splice.h | 3 +++ 2 files changed, 23 insertions(+), 7 deletions(-) diff --git a/fs/splice.c b/fs/splice.c index f9a9be797b0c..d815a69f6589 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -867,12 +867,24 @@ static long do_splice_from(struct pipe_inode_info *pipe, struct file *out, return out->f_op->splice_write(pipe, out, ppos, len, flags); } -/* - * Attempt to initiate a splice from a file to a pipe. +/** + * vfs_splice_read - Read data from a file and splice it into a pipe + * @in: File to splice from + * @ppos: Input file offset + * @pipe: Pipe to splice to + * @len: Number of bytes to splice + * @flags: Splice modifier flags (SPLICE_F_*) + * + * Splice the requested amount of data from the input file to the pipe. This + * is synchronous as the caller must hold the pipe lock across the entire + * operation. + * + * If successful, it returns the amount of data spliced, 0 if it hit the EOF or + * a hole and a negative error code otherwise. */ -static long do_splice_to(struct file *in, loff_t *ppos, - struct pipe_inode_info *pipe, size_t len, - unsigned int flags) +long vfs_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, size_t len, + unsigned int flags) { unsigned int p_space; int ret; @@ -895,6 +907,7 @@ static long do_splice_to(struct file *in, loff_t *ppos, return warn_unsupported(in, "read"); return in->f_op->splice_read(in, ppos, pipe, len, flags); } +EXPORT_SYMBOL_GPL(vfs_splice_read); /** * splice_direct_to_actor - splices data directly between two non-pipes @@ -964,7 +977,7 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd, size_t read_len; loff_t pos = sd->pos, prev_pos = pos; - ret = do_splice_to(in, &pos, pipe, len, flags); + ret = vfs_splice_read(in, &pos, pipe, len, flags); if (unlikely(ret <= 0)) goto out_release; @@ -1112,7 +1125,7 @@ long splice_file_to_pipe(struct file *in, pipe_lock(opipe); ret = wait_for_space(opipe, flags); if (!ret) - ret = do_splice_to(in, offset, opipe, len, flags); + ret = vfs_splice_read(in, offset, opipe, len, flags); pipe_unlock(opipe); if (ret > 0) wakeup_pipe_readers(opipe); diff --git a/include/linux/splice.h b/include/linux/splice.h index a55179fd60fc..8f052c3dae95 100644 --- a/include/linux/splice.h +++ b/include/linux/splice.h @@ -76,6 +76,9 @@ extern ssize_t splice_to_pipe(struct pipe_inode_info *, struct splice_pipe_desc *); extern ssize_t add_to_pipe(struct pipe_inode_info *, struct pipe_buffer *); +long vfs_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, size_t len, + unsigned int flags); extern ssize_t splice_direct_to_actor(struct file *, struct splice_desc *, splice_direct_actor *); extern long do_splice(struct file *in, loff_t *off_in, -- cgit v1.2.3-70-g09d2 From 123856f0e83f457a3a24d15f561a1dd5f0d4b482 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:49:53 +0100 Subject: splice: Check for zero count in vfs_splice_read() Make vfs_splice_read() return immediately if the length is 0. Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: Christian Brauner cc: Jens Axboe cc: Al Viro cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-7-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/splice.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/splice.c b/fs/splice.c index d815a69f6589..fe3309ffeb26 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -891,6 +891,8 @@ long vfs_splice_read(struct file *in, loff_t *ppos, if (unlikely(!(in->f_mode & FMODE_READ))) return -EBADF; + if (!len) + return 0; /* Don't try to read more the pipe has space for. */ p_space = pipe->max_usage - pipe_occupancy(pipe->head, pipe->tail); -- cgit v1.2.3-70-g09d2 From aa3dbde878961dd333cdd3c326b93e6c84a23ed4 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:49:54 +0100 Subject: splice: Make splice from an O_DIRECT fd use copy_splice_read() Make a read splice from a file descriptor that's open O_DIRECT use copy_splice_read() to do the reading as filemap_splice_read() is unlikely to find any pagecache to splice. Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: Christian Brauner cc: Al Viro cc: Jens Axboe cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-8-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/splice.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/splice.c b/fs/splice.c index fe3309ffeb26..76126b1aafcb 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -907,6 +907,12 @@ long vfs_splice_read(struct file *in, loff_t *ppos, if (unlikely(!in->f_op->splice_read)) return warn_unsupported(in, "read"); + /* + * O_DIRECT doesn't deal with the pagecache, so we allocate a buffer, + * copy into it and splice that into the pipe. + */ + if ((in->f_flags & O_DIRECT)) + return copy_splice_read(in, ppos, pipe, len, flags); return in->f_op->splice_read(in, ppos, pipe, len, flags); } EXPORT_SYMBOL_GPL(vfs_splice_read); -- cgit v1.2.3-70-g09d2 From b85930a07738a95047a51dc5bc06b18fd91a9799 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:49:55 +0100 Subject: splice: Make splice from a DAX file use copy_splice_read() Make a read splice from a DAX file go directly to copy_splice_read() to do the reading as filemap_splice_read() is unlikely to find any pagecache to splice. I think this affects only erofs, Ext2, Ext4, fuse and XFS. Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: Christian Brauner Reviewed-by: Theodore Ts'o Reviewed-by: Gao Xiang cc: Al Viro cc: Jens Axboe cc: linux-erofs@lists.ozlabs.org cc: linux-ext4@vger.kernel.org cc: linux-xfs@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-9-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/splice.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/splice.c b/fs/splice.c index 76126b1aafcb..8268248df3a9 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -908,10 +908,10 @@ long vfs_splice_read(struct file *in, loff_t *ppos, if (unlikely(!in->f_op->splice_read)) return warn_unsupported(in, "read"); /* - * O_DIRECT doesn't deal with the pagecache, so we allocate a buffer, - * copy into it and splice that into the pipe. + * O_DIRECT and DAX don't deal with the pagecache, so we allocate a + * buffer, copy into it and splice that into the pipe. */ - if ((in->f_flags & O_DIRECT)) + if ((in->f_flags & O_DIRECT) || IS_DAX(in->f_mapping->host)) return copy_splice_read(in, ppos, pipe, len, flags); return in->f_op->splice_read(in, ppos, pipe, len, flags); } -- cgit v1.2.3-70-g09d2 From bd194b187115da7b98b660b049315f6c9c8267d1 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:49:56 +0100 Subject: shmem: Implement splice-read The new filemap_splice_read() has an implicit expectation via filemap_get_pages() that ->read_folio() exists if ->readahead() doesn't fully populate the pagecache of the file it is reading from[1], potentially leading to a jump to NULL if this doesn't exist. shmem, however, (and by extension, tmpfs, ramfs and rootfs), doesn't have ->read_folio(), Work around this by equipping shmem with its own splice-read implementation, based on filemap_splice_read(), but able to paste in zero_page when there's a page missing. Signed-off-by: David Howells cc: Daniel Golle cc: Guenter Roeck cc: Christoph Hellwig cc: Jens Axboe cc: Al Viro cc: John Hubbard cc: David Hildenbrand cc: Matthew Wilcox cc: Hugh Dickins cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/Y+pdHFFTk1TTEBsO@makrotopia.org/ [1] Link: https://lore.kernel.org/r/20230522135018.2742245-10-dhowells@redhat.com Signed-off-by: Jens Axboe --- mm/shmem.c | 134 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 133 insertions(+), 1 deletion(-) diff --git a/mm/shmem.c b/mm/shmem.c index e40a08c5c6d7..1f504ed982cf 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2731,6 +2731,138 @@ static ssize_t shmem_file_read_iter(struct kiocb *iocb, struct iov_iter *to) return retval ? retval : error; } +static bool zero_pipe_buf_get(struct pipe_inode_info *pipe, + struct pipe_buffer *buf) +{ + return true; +} + +static void zero_pipe_buf_release(struct pipe_inode_info *pipe, + struct pipe_buffer *buf) +{ +} + +static bool zero_pipe_buf_try_steal(struct pipe_inode_info *pipe, + struct pipe_buffer *buf) +{ + return false; +} + +static const struct pipe_buf_operations zero_pipe_buf_ops = { + .release = zero_pipe_buf_release, + .try_steal = zero_pipe_buf_try_steal, + .get = zero_pipe_buf_get, +}; + +static size_t splice_zeropage_into_pipe(struct pipe_inode_info *pipe, + loff_t fpos, size_t size) +{ + size_t offset = fpos & ~PAGE_MASK; + + size = min_t(size_t, size, PAGE_SIZE - offset); + + if (!pipe_full(pipe->head, pipe->tail, pipe->max_usage)) { + struct pipe_buffer *buf = pipe_head_buf(pipe); + + *buf = (struct pipe_buffer) { + .ops = &zero_pipe_buf_ops, + .page = ZERO_PAGE(0), + .offset = offset, + .len = size, + }; + pipe->head++; + } + + return size; +} + +static ssize_t shmem_file_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, + size_t len, unsigned int flags) +{ + struct inode *inode = file_inode(in); + struct address_space *mapping = inode->i_mapping; + struct folio *folio = NULL; + size_t total_spliced = 0, used, npages, n, part; + loff_t isize; + int error = 0; + + /* Work out how much data we can actually add into the pipe */ + used = pipe_occupancy(pipe->head, pipe->tail); + npages = max_t(ssize_t, pipe->max_usage - used, 0); + len = min_t(size_t, len, npages * PAGE_SIZE); + + do { + if (*ppos >= i_size_read(inode)) + break; + + error = shmem_get_folio(inode, *ppos / PAGE_SIZE, &folio, SGP_READ); + if (error) { + if (error == -EINVAL) + error = 0; + break; + } + if (folio) { + folio_unlock(folio); + + if (folio_test_hwpoison(folio)) { + error = -EIO; + break; + } + } + + /* + * i_size must be checked after we know the pages are Uptodate. + * + * Checking i_size after the check allows us to calculate + * the correct value for "nr", which means the zero-filled + * part of the page is not copied back to userspace (unless + * another truncate extends the file - this is desired though). + */ + isize = i_size_read(inode); + if (unlikely(*ppos >= isize)) + break; + part = min_t(loff_t, isize - *ppos, len); + + if (folio) { + /* + * If users can be writing to this page using arbitrary + * virtual addresses, take care about potential aliasing + * before reading the page on the kernel side. + */ + if (mapping_writably_mapped(mapping)) + flush_dcache_folio(folio); + folio_mark_accessed(folio); + /* + * Ok, we have the page, and it's up-to-date, so we can + * now splice it into the pipe. + */ + n = splice_folio_into_pipe(pipe, folio, *ppos, part); + folio_put(folio); + folio = NULL; + } else { + n = splice_zeropage_into_pipe(pipe, *ppos, len); + } + + if (!n) + break; + len -= n; + total_spliced += n; + *ppos += n; + in->f_ra.prev_pos = *ppos; + if (pipe_full(pipe->head, pipe->tail, pipe->max_usage)) + break; + + cond_resched(); + } while (len); + + if (folio) + folio_put(folio); + + file_accessed(in); + return total_spliced ? total_spliced : error; +} + static loff_t shmem_file_llseek(struct file *file, loff_t offset, int whence) { struct address_space *mapping = file->f_mapping; @@ -3971,7 +4103,7 @@ static const struct file_operations shmem_file_operations = { .read_iter = shmem_file_read_iter, .write_iter = generic_file_write_iter, .fsync = noop_fsync, - .splice_read = generic_file_splice_read, + .splice_read = shmem_file_splice_read, .splice_write = iter_file_splice_write, .fallocate = shmem_fallocate, #endif -- cgit v1.2.3-70-g09d2 From d4120d87a0ed197f87c1ce1c8af4177120c2549b Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:49:57 +0100 Subject: overlayfs: Implement splice-read Implement splice-read for overlayfs by passing the request down a layer rather than going through generic_file_splice_read() which is going to be changed to assume that ->read_folio() is present on buffered files. Signed-off-by: David Howells Acked-by: Christian Brauner cc: Christoph Hellwig cc: Jens Axboe cc: Al Viro cc: John Hubbard cc: David Hildenbrand cc: Matthew Wilcox cc: Miklos Szeredi cc: Amir Goldstein cc: linux-unionfs@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-11-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/overlayfs/file.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c index 7c04f033aadd..86197882ff35 100644 --- a/fs/overlayfs/file.c +++ b/fs/overlayfs/file.c @@ -419,6 +419,27 @@ out_unlock: return ret; } +static ssize_t ovl_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, size_t len, + unsigned int flags) +{ + const struct cred *old_cred; + struct fd real; + ssize_t ret; + + ret = ovl_real_fdget(in, &real); + if (ret) + return ret; + + old_cred = ovl_override_creds(file_inode(in)->i_sb); + ret = vfs_splice_read(real.file, ppos, pipe, len, flags); + revert_creds(old_cred); + ovl_file_accessed(in); + + fdput(real); + return ret; +} + /* * Calling iter_file_splice_write() directly from overlay's f_op may deadlock * due to lock order inversion between pipe->mutex in iter_file_splice_write() @@ -695,7 +716,7 @@ const struct file_operations ovl_file_operations = { .fallocate = ovl_fallocate, .fadvise = ovl_fadvise, .flush = ovl_flush, - .splice_read = generic_file_splice_read, + .splice_read = ovl_splice_read, .splice_write = ovl_splice_write, .copy_file_range = ovl_copy_file_range, -- cgit v1.2.3-70-g09d2 From a1be2935d0914ce44e8fcc4e73b3cc6256f96140 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:49:58 +0100 Subject: coda: Implement splice-read Implement splice-read for coda by passing the request down a layer rather than going through generic_file_splice_read() which is going to be changed to assume that ->read_folio() is present on buffered files. Signed-off-by: David Howells Acked-by: Jan Harkes cc: Christoph Hellwig cc: Jens Axboe cc: Al Viro cc: John Hubbard cc: David Hildenbrand cc: Matthew Wilcox cc: coda@cs.cmu.edu cc: codalist@coda.cs.cmu.edu cc: linux-unionfs@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-12-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/coda/file.c | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) diff --git a/fs/coda/file.c b/fs/coda/file.c index 3f3c81e6b1ab..12b26bd13564 100644 --- a/fs/coda/file.c +++ b/fs/coda/file.c @@ -23,6 +23,7 @@ #include #include #include +#include #include #include "coda_psdev.h" @@ -94,6 +95,32 @@ finish_write: return ret; } +static ssize_t +coda_file_splice_read(struct file *coda_file, loff_t *ppos, + struct pipe_inode_info *pipe, + size_t len, unsigned int flags) +{ + struct inode *coda_inode = file_inode(coda_file); + struct coda_file_info *cfi = coda_ftoc(coda_file); + struct file *in = cfi->cfi_container; + loff_t ki_pos = *ppos; + ssize_t ret; + + ret = venus_access_intent(coda_inode->i_sb, coda_i2f(coda_inode), + &cfi->cfi_access_intent, + len, ki_pos, CODA_ACCESS_TYPE_READ); + if (ret) + goto finish_read; + + ret = vfs_splice_read(in, ppos, pipe, len, flags); + +finish_read: + venus_access_intent(coda_inode->i_sb, coda_i2f(coda_inode), + &cfi->cfi_access_intent, + len, ki_pos, CODA_ACCESS_TYPE_READ_FINISH); + return ret; +} + static void coda_vm_open(struct vm_area_struct *vma) { @@ -302,5 +329,5 @@ const struct file_operations coda_file_operations = { .open = coda_open, .release = coda_release, .fsync = coda_fsync, - .splice_read = generic_file_splice_read, + .splice_read = coda_file_splice_read, }; -- cgit v1.2.3-70-g09d2 From b0072734ffaa3f5fec64058d0d3333765d789bc0 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:49:59 +0100 Subject: tty, proc, kernfs, random: Use copy_splice_read() Use copy_splice_read() for tty, procfs, kernfs and random files rather than going through generic_file_splice_read() as they just copy the file into the output buffer and don't splice pages. This avoids the need for them to have a ->read_folio() to satisfy filemap_splice_read(). Signed-off-by: David Howells Acked-by: Greg Kroah-Hartman cc: Christoph Hellwig cc: Jens Axboe cc: Al Viro cc: John Hubbard cc: David Hildenbrand cc: Matthew Wilcox cc: Miklos Szeredi cc: Arnd Bergmann cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-13-dhowells@redhat.com Signed-off-by: Jens Axboe --- drivers/char/random.c | 4 ++-- drivers/tty/tty_io.c | 4 ++-- fs/kernfs/file.c | 2 +- fs/proc/inode.c | 4 ++-- fs/proc/proc_sysctl.c | 2 +- fs/proc_namespace.c | 6 +++--- 6 files changed, 11 insertions(+), 11 deletions(-) diff --git a/drivers/char/random.c b/drivers/char/random.c index 253f2ddb8913..3cb37760dfec 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -1546,7 +1546,7 @@ const struct file_operations random_fops = { .compat_ioctl = compat_ptr_ioctl, .fasync = random_fasync, .llseek = noop_llseek, - .splice_read = generic_file_splice_read, + .splice_read = copy_splice_read, .splice_write = iter_file_splice_write, }; @@ -1557,7 +1557,7 @@ const struct file_operations urandom_fops = { .compat_ioctl = compat_ptr_ioctl, .fasync = random_fasync, .llseek = noop_llseek, - .splice_read = generic_file_splice_read, + .splice_read = copy_splice_read, .splice_write = iter_file_splice_write, }; diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c index c84be40fb8df..4737a8f92c2e 100644 --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -466,7 +466,7 @@ static const struct file_operations tty_fops = { .llseek = no_llseek, .read_iter = tty_read, .write_iter = tty_write, - .splice_read = generic_file_splice_read, + .splice_read = copy_splice_read, .splice_write = iter_file_splice_write, .poll = tty_poll, .unlocked_ioctl = tty_ioctl, @@ -481,7 +481,7 @@ static const struct file_operations console_fops = { .llseek = no_llseek, .read_iter = tty_read, .write_iter = redirected_tty_write, - .splice_read = generic_file_splice_read, + .splice_read = copy_splice_read, .splice_write = iter_file_splice_write, .poll = tty_poll, .unlocked_ioctl = tty_ioctl, diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c index 40c4661f15b7..180906c36f51 100644 --- a/fs/kernfs/file.c +++ b/fs/kernfs/file.c @@ -1011,7 +1011,7 @@ const struct file_operations kernfs_file_fops = { .release = kernfs_fop_release, .poll = kernfs_fop_poll, .fsync = noop_fsync, - .splice_read = generic_file_splice_read, + .splice_read = copy_splice_read, .splice_write = iter_file_splice_write, }; diff --git a/fs/proc/inode.c b/fs/proc/inode.c index f495fdb39151..67b09a1d9433 100644 --- a/fs/proc/inode.c +++ b/fs/proc/inode.c @@ -591,7 +591,7 @@ static const struct file_operations proc_iter_file_ops = { .llseek = proc_reg_llseek, .read_iter = proc_reg_read_iter, .write = proc_reg_write, - .splice_read = generic_file_splice_read, + .splice_read = copy_splice_read, .poll = proc_reg_poll, .unlocked_ioctl = proc_reg_unlocked_ioctl, .mmap = proc_reg_mmap, @@ -617,7 +617,7 @@ static const struct file_operations proc_reg_file_ops_compat = { static const struct file_operations proc_iter_file_ops_compat = { .llseek = proc_reg_llseek, .read_iter = proc_reg_read_iter, - .splice_read = generic_file_splice_read, + .splice_read = copy_splice_read, .write = proc_reg_write, .poll = proc_reg_poll, .unlocked_ioctl = proc_reg_unlocked_ioctl, diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index 8038833ff5b0..ae832e982003 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -868,7 +868,7 @@ static const struct file_operations proc_sys_file_operations = { .poll = proc_sys_poll, .read_iter = proc_sys_read, .write_iter = proc_sys_write, - .splice_read = generic_file_splice_read, + .splice_read = copy_splice_read, .splice_write = iter_file_splice_write, .llseek = default_llseek, }; diff --git a/fs/proc_namespace.c b/fs/proc_namespace.c index 846f9455ae22..250eb5bf7b52 100644 --- a/fs/proc_namespace.c +++ b/fs/proc_namespace.c @@ -324,7 +324,7 @@ static int mountstats_open(struct inode *inode, struct file *file) const struct file_operations proc_mounts_operations = { .open = mounts_open, .read_iter = seq_read_iter, - .splice_read = generic_file_splice_read, + .splice_read = copy_splice_read, .llseek = seq_lseek, .release = mounts_release, .poll = mounts_poll, @@ -333,7 +333,7 @@ const struct file_operations proc_mounts_operations = { const struct file_operations proc_mountinfo_operations = { .open = mountinfo_open, .read_iter = seq_read_iter, - .splice_read = generic_file_splice_read, + .splice_read = copy_splice_read, .llseek = seq_lseek, .release = mounts_release, .poll = mounts_poll, @@ -342,7 +342,7 @@ const struct file_operations proc_mountinfo_operations = { const struct file_operations proc_mountstats_operations = { .open = mountstats_open, .read_iter = seq_read_iter, - .splice_read = generic_file_splice_read, + .splice_read = copy_splice_read, .llseek = seq_lseek, .release = mounts_release, }; -- cgit v1.2.3-70-g09d2 From 67178fd066d53d5a6cada1cdc6399d02b68b708e Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:00 +0100 Subject: net: Make sock_splice_read() use copy_splice_read() by default Make sock_splice_read() use copy_splice_read() by default as file_splice_read() will return immediately with 0 as a socket has no pagecache and is a zero-size file. Signed-off-by: David Howells cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: Christoph Hellwig cc: Al Viro cc: Jens Axboe cc: netdev@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-14-dhowells@redhat.com Signed-off-by: Jens Axboe --- net/socket.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/socket.c b/net/socket.c index b7e01d0fe082..401778380195 100644 --- a/net/socket.c +++ b/net/socket.c @@ -1093,7 +1093,7 @@ static ssize_t sock_splice_read(struct file *file, loff_t *ppos, struct socket *sock = file->private_data; if (unlikely(!sock->ops->splice_read)) - return generic_file_splice_read(file, ppos, pipe, len, flags); + return copy_splice_read(file, ppos, pipe, len, flags); return sock->ops->splice_read(sock, ppos, pipe, len, flags); } -- cgit v1.2.3-70-g09d2 From c829d0bd33ac0df8cece64e50ec71a63f17790f8 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:01 +0100 Subject: 9p: Add splice_read wrapper Add a splice_read wrapper for 9p. We should use copy_splice_read() if 9PL_DIRECT is set and filemap_splice_read() otherwise. Note that this doesn't seem to be particularly related to O_DIRECT. Signed-off-by: David Howells cc: Christoph Hellwig cc: Al Viro cc: Jens Axboe cc: Dominique Martinet cc: Eric Van Hensbergen cc: Latchesar Ionkov cc: Christian Schoenebeck cc: v9fs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-15-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/9p/vfs_file.c | 26 ++++++++++++++++++++++++-- 1 file changed, 24 insertions(+), 2 deletions(-) diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c index 6c31b8c8112d..2996fb00387f 100644 --- a/fs/9p/vfs_file.c +++ b/fs/9p/vfs_file.c @@ -374,6 +374,28 @@ v9fs_file_read_iter(struct kiocb *iocb, struct iov_iter *to) return ret; } +/* + * v9fs_file_splice_read - splice-read from a file + * @in: The 9p file to read from + * @ppos: Where to find/update the file position + * @pipe: The pipe to splice into + * @len: The maximum amount of data to splice + * @flags: SPLICE_F_* flags + */ +static ssize_t v9fs_file_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, + size_t len, unsigned int flags) +{ + struct p9_fid *fid = in->private_data; + + p9_debug(P9_DEBUG_VFS, "fid %d count %zu offset %lld\n", + fid->fid, len, *ppos); + + if (fid->mode & P9L_DIRECT) + return copy_splice_read(in, ppos, pipe, len, flags); + return filemap_splice_read(in, ppos, pipe, len, flags); +} + /** * v9fs_file_write_iter - write to a file * @iocb: The operation parameters @@ -569,7 +591,7 @@ const struct file_operations v9fs_file_operations = { .release = v9fs_dir_release, .lock = v9fs_file_lock, .mmap = generic_file_readonly_mmap, - .splice_read = generic_file_splice_read, + .splice_read = v9fs_file_splice_read, .splice_write = iter_file_splice_write, .fsync = v9fs_file_fsync, }; @@ -583,7 +605,7 @@ const struct file_operations v9fs_file_operations_dotl = { .lock = v9fs_file_lock_dotl, .flock = v9fs_file_flock_dotl, .mmap = v9fs_file_mmap, - .splice_read = generic_file_splice_read, + .splice_read = v9fs_file_splice_read, .splice_write = iter_file_splice_write, .fsync = v9fs_file_fsync_dotl, }; -- cgit v1.2.3-70-g09d2 From d96d96eebb06d41010a86cf56b4d9ea47f597152 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:02 +0100 Subject: afs: Provide a splice-read wrapper Provide a splice_read wrapper for AFS to call afs_validate() before going into generic_file_splice_read() so that we're likely to have a callback promise from the server. Signed-off-by: David Howells cc: Christoph Hellwig cc: Al Viro cc: Jens Axboe cc: Marc Dionne cc: linux-afs@lists.infradead.org cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-16-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/afs/file.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/fs/afs/file.c b/fs/afs/file.c index 719b31374879..d8a6b09dadf7 100644 --- a/fs/afs/file.c +++ b/fs/afs/file.c @@ -25,6 +25,9 @@ static void afs_invalidate_folio(struct folio *folio, size_t offset, static bool afs_release_folio(struct folio *folio, gfp_t gfp_flags); static ssize_t afs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter); +static ssize_t afs_file_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, + size_t len, unsigned int flags); static void afs_vm_open(struct vm_area_struct *area); static void afs_vm_close(struct vm_area_struct *area); static vm_fault_t afs_vm_map_pages(struct vm_fault *vmf, pgoff_t start_pgoff, pgoff_t end_pgoff); @@ -36,7 +39,7 @@ const struct file_operations afs_file_operations = { .read_iter = afs_file_read_iter, .write_iter = afs_file_write, .mmap = afs_file_mmap, - .splice_read = generic_file_splice_read, + .splice_read = afs_file_splice_read, .splice_write = iter_file_splice_write, .fsync = afs_fsync, .lock = afs_lock, @@ -587,3 +590,18 @@ static ssize_t afs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter) return generic_file_read_iter(iocb, iter); } + +static ssize_t afs_file_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, + size_t len, unsigned int flags) +{ + struct afs_vnode *vnode = AFS_FS_I(file_inode(in)); + struct afs_file *af = in->private_data; + int ret; + + ret = afs_validate(vnode, af->key); + if (ret < 0) + return ret; + + return generic_file_splice_read(in, ppos, pipe, len, flags); +} -- cgit v1.2.3-70-g09d2 From ccfdf7cbb5fe332f8d17b6eca88d96d881dd77b9 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:03 +0100 Subject: ceph: Provide a splice-read wrapper Provide a splice_read wrapper for Ceph. This does the inode shutdown check before proceeding and jumps to copy_splice_read() if the file has inline data or is a synchronous file. We try and get FILE_RD and either FILE_CACHE and/or FILE_LAZYIO caps and hold them across filemap_splice_read(). If we fail to get FILE_CACHE or FILE_LAZYIO capabilities, we use copy_splice_read() instead. Signed-off-by: David Howells Reviewed-by: Xiubo Li cc: Christoph Hellwig cc: Al Viro cc: Jens Axboe cc: Ilya Dryomov cc: Jeff Layton cc: ceph-devel@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-17-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/ceph/file.c | 65 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 64 insertions(+), 1 deletion(-) diff --git a/fs/ceph/file.c b/fs/ceph/file.c index f4d8bf7dec88..4285f6cb5d3b 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -1745,6 +1745,69 @@ again: return ret; } +/* + * Wrap filemap_splice_read with checks for cap bits on the inode. + * Atomically grab references, so that those bits are not released + * back to the MDS mid-read. + */ +static ssize_t ceph_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, + size_t len, unsigned int flags) +{ + struct ceph_file_info *fi = in->private_data; + struct inode *inode = file_inode(in); + struct ceph_inode_info *ci = ceph_inode(inode); + ssize_t ret; + int want = 0, got = 0; + CEPH_DEFINE_RW_CONTEXT(rw_ctx, 0); + + dout("splice_read %p %llx.%llx %llu~%zu trying to get caps on %p\n", + inode, ceph_vinop(inode), *ppos, len, inode); + + if (ceph_inode_is_shutdown(inode)) + return -ESTALE; + + if (ceph_has_inline_data(ci) || + (fi->flags & CEPH_F_SYNC)) + return copy_splice_read(in, ppos, pipe, len, flags); + + ceph_start_io_read(inode); + + want = CEPH_CAP_FILE_CACHE; + if (fi->fmode & CEPH_FILE_MODE_LAZY) + want |= CEPH_CAP_FILE_LAZYIO; + + ret = ceph_get_caps(in, CEPH_CAP_FILE_RD, want, -1, &got); + if (ret < 0) + goto out_end; + + if ((got & (CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO)) == 0) { + dout("splice_read/sync %p %llx.%llx %llu~%zu got cap refs on %s\n", + inode, ceph_vinop(inode), *ppos, len, + ceph_cap_string(got)); + + ceph_put_cap_refs(ci, got); + ceph_end_io_read(inode); + return copy_splice_read(in, ppos, pipe, len, flags); + } + + dout("splice_read %p %llx.%llx %llu~%zu got cap refs on %s\n", + inode, ceph_vinop(inode), *ppos, len, ceph_cap_string(got)); + + rw_ctx.caps = got; + ceph_add_rw_context(fi, &rw_ctx); + ret = filemap_splice_read(in, ppos, pipe, len, flags); + ceph_del_rw_context(fi, &rw_ctx); + + dout("splice_read %p %llx.%llx dropping cap refs on %s = %zd\n", + inode, ceph_vinop(inode), ceph_cap_string(got), ret); + + ceph_put_cap_refs(ci, got); +out_end: + ceph_end_io_read(inode); + return ret; +} + /* * Take cap references to avoid releasing caps to MDS mid-write. * @@ -2593,7 +2656,7 @@ const struct file_operations ceph_file_fops = { .lock = ceph_lock, .setlease = simple_nosetlease, .flock = ceph_flock, - .splice_read = generic_file_splice_read, + .splice_read = ceph_splice_read, .splice_write = iter_file_splice_write, .unlocked_ioctl = ceph_ioctl, .compat_ioctl = compat_ptr_ioctl, -- cgit v1.2.3-70-g09d2 From 390df3b830e758e970a0ba928a97f8bbd5385f0c Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:04 +0100 Subject: ecryptfs: Provide a splice-read wrapper Provide a splice_read wrapper for ecryptfs to update the access time on the lower file after the operation. Splicing from a direct I/O fd will update the access time when ->read_iter() is called. Signed-off-by: David Howells cc: Christoph Hellwig cc: Al Viro cc: Jens Axboe cc: Tyler Hicks cc: ecryptfs@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-18-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/ecryptfs/file.c | 27 ++++++++++++++++++++++++++- 1 file changed, 26 insertions(+), 1 deletion(-) diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c index 268b74499c28..284395587be0 100644 --- a/fs/ecryptfs/file.c +++ b/fs/ecryptfs/file.c @@ -44,6 +44,31 @@ static ssize_t ecryptfs_read_update_atime(struct kiocb *iocb, return rc; } +/* + * ecryptfs_splice_read_update_atime + * + * generic_file_splice_read updates the atime of upper layer inode. But, it + * doesn't give us a chance to update the atime of the lower layer inode. This + * function is a wrapper to generic_file_read. It updates the atime of the + * lower level inode if generic_file_read returns without any errors. This is + * to be used only for file reads. The function to be used for directory reads + * is ecryptfs_read. + */ +static ssize_t ecryptfs_splice_read_update_atime(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, + size_t len, unsigned int flags) +{ + ssize_t rc; + const struct path *path; + + rc = generic_file_splice_read(in, ppos, pipe, len, flags); + if (rc >= 0) { + path = ecryptfs_dentry_to_lower_path(in->f_path.dentry); + touch_atime(path); + } + return rc; +} + struct ecryptfs_getdents_callback { struct dir_context ctx; struct dir_context *caller; @@ -414,5 +439,5 @@ const struct file_operations ecryptfs_main_fops = { .release = ecryptfs_release, .fsync = ecryptfs_fsync, .fasync = ecryptfs_fasync, - .splice_read = generic_file_splice_read, + .splice_read = ecryptfs_splice_read_update_atime, }; -- cgit v1.2.3-70-g09d2 From fa6c46e7c271f155c9ba3ba3457175c0a71eb918 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:05 +0100 Subject: ext4: Provide a splice-read wrapper Provide a splice_read wrapper for Ext4. This does the inode shutdown check before proceeding. Splicing from DAX files and O_DIRECT fds is handled by the caller. Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Acked-by: Theodore Ts'o cc: Al Viro cc: Jens Axboe cc: Andreas Dilger cc: linux-ext4@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-19-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/ext4/file.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/fs/ext4/file.c b/fs/ext4/file.c index d101b3b0c7da..9f8bbd9d131c 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -147,6 +147,17 @@ static ssize_t ext4_file_read_iter(struct kiocb *iocb, struct iov_iter *to) return generic_file_read_iter(iocb, to); } +static ssize_t ext4_file_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, + size_t len, unsigned int flags) +{ + struct inode *inode = file_inode(in); + + if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) + return -EIO; + return generic_file_splice_read(in, ppos, pipe, len, flags); +} + /* * Called when an inode is released. Note that this is different * from ext4_file_open: open gets called at every open, but release @@ -957,7 +968,7 @@ const struct file_operations ext4_file_operations = { .release = ext4_release_file, .fsync = ext4_sync_file, .get_unmapped_area = thp_get_unmapped_area, - .splice_read = generic_file_splice_read, + .splice_read = ext4_file_splice_read, .splice_write = iter_file_splice_write, .fallocate = ext4_fallocate, }; -- cgit v1.2.3-70-g09d2 From ceb11d0e2da275ca763de25cd129cf7cce56509b Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:06 +0100 Subject: f2fs: Provide a splice-read wrapper Provide a splice_read wrapper for f2fs. This does some checks and tracing before calling filemap_splice_read() and will update the iostats afterwards. Direct I/O is handled by the caller. Signed-off-by: David Howells cc: Christoph Hellwig cc: Al Viro cc: Jens Axboe cc: Jaegeuk Kim cc: Chao Yu cc: linux-f2fs-devel@lists.sourceforge.net cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-20-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/f2fs/file.c | 43 +++++++++++++++++++++++++++++++++++-------- 1 file changed, 35 insertions(+), 8 deletions(-) diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index 5ac53d2627d2..3fce122997ca 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -4367,22 +4367,23 @@ out: return ret; } -static void f2fs_trace_rw_file_path(struct kiocb *iocb, size_t count, int rw) +static void f2fs_trace_rw_file_path(struct file *file, loff_t pos, size_t count, + int rw) { - struct inode *inode = file_inode(iocb->ki_filp); + struct inode *inode = file_inode(file); char *buf, *path; buf = f2fs_getname(F2FS_I_SB(inode)); if (!buf) return; - path = dentry_path_raw(file_dentry(iocb->ki_filp), buf, PATH_MAX); + path = dentry_path_raw(file_dentry(file), buf, PATH_MAX); if (IS_ERR(path)) goto free_buf; if (rw == WRITE) - trace_f2fs_datawrite_start(inode, iocb->ki_pos, count, + trace_f2fs_datawrite_start(inode, pos, count, current->pid, path, current->comm); else - trace_f2fs_dataread_start(inode, iocb->ki_pos, count, + trace_f2fs_dataread_start(inode, pos, count, current->pid, path, current->comm); free_buf: f2fs_putname(buf); @@ -4398,7 +4399,8 @@ static ssize_t f2fs_file_read_iter(struct kiocb *iocb, struct iov_iter *to) return -EOPNOTSUPP; if (trace_f2fs_dataread_start_enabled()) - f2fs_trace_rw_file_path(iocb, iov_iter_count(to), READ); + f2fs_trace_rw_file_path(iocb->ki_filp, iocb->ki_pos, + iov_iter_count(to), READ); if (f2fs_should_use_dio(inode, iocb, to)) { ret = f2fs_dio_read_iter(iocb, to); @@ -4413,6 +4415,30 @@ static ssize_t f2fs_file_read_iter(struct kiocb *iocb, struct iov_iter *to) return ret; } +static ssize_t f2fs_file_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, + size_t len, unsigned int flags) +{ + struct inode *inode = file_inode(in); + const loff_t pos = *ppos; + ssize_t ret; + + if (!f2fs_is_compress_backend_ready(inode)) + return -EOPNOTSUPP; + + if (trace_f2fs_dataread_start_enabled()) + f2fs_trace_rw_file_path(in, pos, len, READ); + + ret = filemap_splice_read(in, ppos, pipe, len, flags); + if (ret > 0) + f2fs_update_iostat(F2FS_I_SB(inode), inode, + APP_BUFFERED_READ_IO, ret); + + if (trace_f2fs_dataread_end_enabled()) + trace_f2fs_dataread_end(inode, pos, ret); + return ret; +} + static ssize_t f2fs_write_checks(struct kiocb *iocb, struct iov_iter *from) { struct file *file = iocb->ki_filp; @@ -4714,7 +4740,8 @@ static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from) ret = preallocated; } else { if (trace_f2fs_datawrite_start_enabled()) - f2fs_trace_rw_file_path(iocb, orig_count, WRITE); + f2fs_trace_rw_file_path(iocb->ki_filp, iocb->ki_pos, + orig_count, WRITE); /* Do the actual write. */ ret = dio ? @@ -4919,7 +4946,7 @@ const struct file_operations f2fs_file_operations = { #ifdef CONFIG_COMPAT .compat_ioctl = f2fs_compat_ioctl, #endif - .splice_read = generic_file_splice_read, + .splice_read = f2fs_file_splice_read, .splice_write = iter_file_splice_write, .fadvise = f2fs_file_fadvise, }; -- cgit v1.2.3-70-g09d2 From a7db503401eecfdab4fa6e7df9dd7214cb8759a4 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:07 +0100 Subject: nfs: Provide a splice-read wrapper Provide a splice_read wrapper for NFS. This locks the inode around filemap_splice_read() and revalidates the mapping. Splicing from direct I/O is handled by the caller. Signed-off-by: David Howells cc: Christoph Hellwig cc: Al Viro cc: Jens Axboe cc: Trond Myklebust cc: Anna Schumaker cc: linux-nfs@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-21-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/nfs/file.c | 23 ++++++++++++++++++++++- fs/nfs/internal.h | 2 ++ fs/nfs/nfs4file.c | 2 +- 3 files changed, 25 insertions(+), 2 deletions(-) diff --git a/fs/nfs/file.c b/fs/nfs/file.c index f0edf5a36237..3855f3ce8d2d 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -178,6 +178,27 @@ nfs_file_read(struct kiocb *iocb, struct iov_iter *to) } EXPORT_SYMBOL_GPL(nfs_file_read); +ssize_t +nfs_file_splice_read(struct file *in, loff_t *ppos, struct pipe_inode_info *pipe, + size_t len, unsigned int flags) +{ + struct inode *inode = file_inode(in); + ssize_t result; + + dprintk("NFS: splice_read(%pD2, %zu@%llu)\n", in, len, *ppos); + + nfs_start_io_read(inode); + result = nfs_revalidate_mapping(inode, in->f_mapping); + if (!result) { + result = filemap_splice_read(in, ppos, pipe, len, flags); + if (result > 0) + nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, result); + } + nfs_end_io_read(inode); + return result; +} +EXPORT_SYMBOL_GPL(nfs_file_splice_read); + int nfs_file_mmap(struct file * file, struct vm_area_struct * vma) { @@ -879,7 +900,7 @@ const struct file_operations nfs_file_operations = { .fsync = nfs_file_fsync, .lock = nfs_lock, .flock = nfs_flock, - .splice_read = generic_file_splice_read, + .splice_read = nfs_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 3cc027d3bd58..b5f21d35d30e 100644 --- a/fs/nfs/internal.h +++ b/fs/nfs/internal.h @@ -416,6 +416,8 @@ static inline __u32 nfs_access_xattr_mask(const struct nfs_server *server) 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 *in, loff_t *ppos, struct pipe_inode_info *pipe, + size_t len, unsigned int flags); 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 2563ed8580f3..4aeadd6e1a6d 100644 --- a/fs/nfs/nfs4file.c +++ b/fs/nfs/nfs4file.c @@ -454,7 +454,7 @@ const struct file_operations nfs4_file_operations = { .fsync = nfs_file_fsync, .lock = nfs_lock, .flock = nfs_flock, - .splice_read = generic_file_splice_read, + .splice_read = nfs_file_splice_read, .splice_write = iter_file_splice_write, .check_flags = nfs_check_flags, .setlease = nfs4_setlease, -- cgit v1.2.3-70-g09d2 From 51494398807111ee0f78e03c485c422195f8cf98 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:08 +0100 Subject: ntfs3: Provide a splice-read wrapper Provide a splice_read wrapper for NTFS3 to perform various checks before allowing the operation to proceed. Signed-off-by: David Howells cc: Christoph Hellwig cc: Al Viro cc: Jens Axboe cc: Konstantin Komarov cc: ntfs3@lists.linux.dev cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-22-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/ntfs3/file.c | 31 ++++++++++++++++++++++++++++++- 1 file changed, 30 insertions(+), 1 deletion(-) diff --git a/fs/ntfs3/file.c b/fs/ntfs3/file.c index 9a3d55c367d9..667c9dc68b58 100644 --- a/fs/ntfs3/file.c +++ b/fs/ntfs3/file.c @@ -744,6 +744,35 @@ static ssize_t ntfs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter) return generic_file_read_iter(iocb, iter); } +static ssize_t ntfs_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 ntfs_inode *ni = ntfs_i(inode); + + if (is_encrypted(ni)) { + ntfs_inode_warn(inode, "encrypted i/o not supported"); + return -EOPNOTSUPP; + } + +#ifndef CONFIG_NTFS3_LZX_XPRESS + if (ni->ni_flags & NI_FLAG_COMPRESSED_MASK) { + ntfs_inode_warn( + inode, + "activate CONFIG_NTFS3_LZX_XPRESS to read external compressed files"); + return -EOPNOTSUPP; + } +#endif + + if (is_dedup(ni)) { + ntfs_inode_warn(inode, "read deduplicated not supported"); + return -EOPNOTSUPP; + } + + return generic_file_splice_read(in, ppos, pipe, len, flags); +} + /* * ntfs_get_frame_pages * @@ -1159,7 +1188,7 @@ const struct file_operations ntfs_file_operations = { #ifdef CONFIG_COMPAT .compat_ioctl = ntfs_compat_ioctl, #endif - .splice_read = generic_file_splice_read, + .splice_read = ntfs_file_splice_read, .mmap = ntfs_file_mmap, .open = ntfs_file_open, .fsync = generic_file_fsync, -- cgit v1.2.3-70-g09d2 From 94aca682a4eb10fe32bf3f124de9f30b9249cae0 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:09 +0100 Subject: ocfs2: Provide a splice-read wrapper Provide a splice_read wrapper for ocfs2. This emits trace lines and does an atime lock/update before calling filemap_splice_read(). Splicing from direct I/O is handled by the caller. A couple of new tracepoints are added for this purpose. Signed-off-by: David Howells Reviewed-by: Joseph Qi cc: Christoph Hellwig cc: Al Viro cc: Jens Axboe cc: Mark Fasheh cc: Joel Becker cc: ocfs2-devel@oss.oracle.com cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-23-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/ocfs2/file.c | 41 +++++++++++++++++++++++++++++++++++++++-- fs/ocfs2/ocfs2_trace.h | 3 +++ 2 files changed, 42 insertions(+), 2 deletions(-) diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c index efb09de4343d..86add13b5f23 100644 --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -2552,7 +2552,7 @@ static ssize_t ocfs2_file_read_iter(struct kiocb *iocb, * * Take and drop the meta data lock to update inode fields * like i_size. This allows the checks down below - * generic_file_read_iter() a chance of actually working. + * copy_splice_read() a chance of actually working. */ ret = ocfs2_inode_lock_atime(inode, filp->f_path.mnt, &lock_level, !nowait); @@ -2581,6 +2581,43 @@ bail: 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) +{ + struct inode *inode = file_inode(in); + ssize_t ret = 0; + int lock_level = 0; + + 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, + flags); + + /* + * We're fine letting folks race truncates and extending writes with + * read across the cluster, just like they can locally. Hence no + * rw_lock during read. + * + * Take and drop the meta data lock to update inode fields like i_size. + * This allows the checks down below filemap_splice_read() a chance of + * actually working. + */ + ret = ocfs2_inode_lock_atime(inode, in->f_path.mnt, &lock_level, 1); + if (ret < 0) { + if (ret != -EAGAIN) + mlog_errno(ret); + goto bail; + } + ocfs2_inode_unlock(inode, lock_level); + + ret = filemap_splice_read(in, ppos, pipe, len, flags); + trace_filemap_splice_read_ret(ret); +bail: + return ret; +} + /* Refer generic_file_llseek_unlocked() */ static loff_t ocfs2_file_llseek(struct file *file, loff_t offset, int whence) { @@ -2744,7 +2781,7 @@ const struct file_operations ocfs2_fops = { #endif .lock = ocfs2_lock, .flock = ocfs2_flock, - .splice_read = generic_file_splice_read, + .splice_read = ocfs2_file_splice_read, .splice_write = iter_file_splice_write, .fallocate = ocfs2_fallocate, .remap_file_range = ocfs2_remap_file_range, diff --git a/fs/ocfs2/ocfs2_trace.h b/fs/ocfs2/ocfs2_trace.h index dc4bce1649c1..b8c3d1702076 100644 --- a/fs/ocfs2/ocfs2_trace.h +++ b/fs/ocfs2/ocfs2_trace.h @@ -1319,6 +1319,8 @@ DEFINE_OCFS2_FILE_OPS(ocfs2_file_splice_write); DEFINE_OCFS2_FILE_OPS(ocfs2_file_read_iter); +DEFINE_OCFS2_FILE_OPS(ocfs2_file_splice_read); + DEFINE_OCFS2_ULL_ULL_ULL_EVENT(ocfs2_truncate_file); DEFINE_OCFS2_ULL_ULL_EVENT(ocfs2_truncate_file_error); @@ -1470,6 +1472,7 @@ TRACE_EVENT(ocfs2_prepare_inode_for_write, ); DEFINE_OCFS2_INT_EVENT(generic_file_read_iter_ret); +DEFINE_OCFS2_INT_EVENT(filemap_splice_read_ret); /* End of trace events for fs/ocfs2/file.c. */ -- cgit v1.2.3-70-g09d2 From 6bbf64beabc1bdcd96474c5eb26f38258c4aea44 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:10 +0100 Subject: orangefs: Provide a splice-read wrapper Provide a splice_read wrapper for ocfs2. This increments the read stats and then locks the inode across the call to filemap_splice_read() and a revalidation of the mapping. Splicing from direct I/O is done by the caller. Signed-off-by: David Howells cc: Christoph Hellwig cc: Al Viro cc: Jens Axboe cc: Mike Marshall cc: Martin Brandenburg cc: devel@lists.orangefs.org cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-24-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/orangefs/file.c | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-) diff --git a/fs/orangefs/file.c b/fs/orangefs/file.c index 1a4301a38aa7..d68372241b30 100644 --- a/fs/orangefs/file.c +++ b/fs/orangefs/file.c @@ -337,6 +337,26 @@ out: return ret; } +static ssize_t orangefs_file_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, + size_t len, unsigned int flags) +{ + struct inode *inode = file_inode(in); + ssize_t ret; + + orangefs_stats.reads++; + + down_read(&inode->i_rwsem); + ret = orangefs_revalidate_mapping(inode); + if (ret) + goto out; + + ret = filemap_splice_read(in, ppos, pipe, len, flags); +out: + up_read(&inode->i_rwsem); + return ret; +} + static ssize_t orangefs_file_write_iter(struct kiocb *iocb, struct iov_iter *iter) { @@ -556,7 +576,7 @@ const struct file_operations orangefs_file_operations = { .lock = orangefs_lock, .mmap = orangefs_file_mmap, .open = generic_file_open, - .splice_read = generic_file_splice_read, + .splice_read = orangefs_file_splice_read, .splice_write = iter_file_splice_write, .flush = orangefs_flush, .release = orangefs_file_release, -- cgit v1.2.3-70-g09d2 From 54919f94ec52549b7efcd074567ccb68c49830df Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:11 +0100 Subject: xfs: Provide a splice-read wrapper Provide a splice_read wrapper for XFS. This does a stat count and a shutdown check before proceeding, then emits a new trace line and locks the inode across the call to filemap_splice_read() and adds to the stats afterwards. Splicing from direct I/O or DAX is handled by the caller. Signed-off-by: David Howells Reviewed-by: Christoph Hellwig cc: Al Viro cc: Jens Axboe cc: Darrick J. Wong cc: linux-xfs@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-25-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/xfs/xfs_file.c | 30 +++++++++++++++++++++++++++++- fs/xfs/xfs_trace.h | 2 +- 2 files changed, 30 insertions(+), 2 deletions(-) diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index aede746541f8..08d632668e94 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -306,6 +306,34 @@ xfs_file_read_iter( return ret; } +STATIC ssize_t +xfs_file_splice_read( + struct file *in, + loff_t *ppos, + struct pipe_inode_info *pipe, + size_t len, + unsigned int flags) +{ + struct inode *inode = file_inode(in); + struct xfs_inode *ip = XFS_I(inode); + struct xfs_mount *mp = ip->i_mount; + ssize_t ret = 0; + + XFS_STATS_INC(mp, xs_read_calls); + + if (xfs_is_shutdown(mp)) + return -EIO; + + trace_xfs_file_splice_read(ip, *ppos, len); + + xfs_ilock(ip, XFS_IOLOCK_SHARED); + ret = filemap_splice_read(in, ppos, pipe, len, flags); + xfs_iunlock(ip, XFS_IOLOCK_SHARED); + if (ret > 0) + XFS_STATS_ADD(mp, xs_read_bytes, ret); + return ret; +} + /* * Common pre-write limit and setup checks. * @@ -1423,7 +1451,7 @@ 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 = generic_file_splice_read, + .splice_read = xfs_file_splice_read, .splice_write = iter_file_splice_write, .iopoll = iocb_bio_iopoll, .unlocked_ioctl = xfs_file_ioctl, diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h index cd4ca5b1fcb0..4db669203149 100644 --- a/fs/xfs/xfs_trace.h +++ b/fs/xfs/xfs_trace.h @@ -1445,7 +1445,6 @@ DEFINE_RW_EVENT(xfs_file_direct_write); DEFINE_RW_EVENT(xfs_file_dax_write); DEFINE_RW_EVENT(xfs_reflink_bounce_dio_write); - DECLARE_EVENT_CLASS(xfs_imap_class, TP_PROTO(struct xfs_inode *ip, xfs_off_t offset, ssize_t count, int whichfork, struct xfs_bmbt_irec *irec), @@ -1535,6 +1534,7 @@ DEFINE_SIMPLE_IO_EVENT(xfs_zero_eof); DEFINE_SIMPLE_IO_EVENT(xfs_end_io_direct_write); DEFINE_SIMPLE_IO_EVENT(xfs_end_io_direct_write_unwritten); DEFINE_SIMPLE_IO_EVENT(xfs_end_io_direct_write_append); +DEFINE_SIMPLE_IO_EVENT(xfs_file_splice_read); DECLARE_EVENT_CLASS(xfs_itrunc_class, TP_PROTO(struct xfs_inode *ip, xfs_fsize_t new_size), -- cgit v1.2.3-70-g09d2 From 6ef48ec391c8733c89fce33b5a6a2747aa1b8178 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:12 +0100 Subject: zonefs: Provide a splice-read wrapper Provide a splice_read wrapper for zonefs. This does some checks before proceeding and locks the inode across the call to filemap_splice_read() and a size check in case of truncation. Splicing from direct I/O is handled by the caller. Signed-off-by: David Howells cc: Christoph Hellwig cc: Al Viro cc: Jens Axboe cc: Darrick J. Wong cc: linux-xfs@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org Acked-by: Damien Le Moal Link: https://lore.kernel.org/r/20230522135018.2742245-26-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/zonefs/file.c | 40 +++++++++++++++++++++++++++++++++++++++- 1 file changed, 39 insertions(+), 1 deletion(-) diff --git a/fs/zonefs/file.c b/fs/zonefs/file.c index 132f01d3461f..65d4c4fe6364 100644 --- a/fs/zonefs/file.c +++ b/fs/zonefs/file.c @@ -752,6 +752,44 @@ inode_unlock: return ret; } +static ssize_t zonefs_file_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, + size_t len, unsigned int flags) +{ + struct inode *inode = file_inode(in); + struct zonefs_inode_info *zi = ZONEFS_I(inode); + struct zonefs_zone *z = zonefs_inode_zone(inode); + loff_t isize; + ssize_t ret = 0; + + /* Offline zones cannot be read */ + if (unlikely(IS_IMMUTABLE(inode) && !(inode->i_mode & 0777))) + return -EPERM; + + if (*ppos >= z->z_capacity) + return 0; + + inode_lock_shared(inode); + + /* Limit read operations to written data */ + mutex_lock(&zi->i_truncate_mutex); + isize = i_size_read(inode); + if (*ppos >= isize) + len = 0; + else + len = min_t(loff_t, len, isize - *ppos); + mutex_unlock(&zi->i_truncate_mutex); + + if (len > 0) { + ret = filemap_splice_read(in, ppos, pipe, len, flags); + if (ret == -EIO) + zonefs_io_error(inode, false); + } + + inode_unlock_shared(inode); + return ret; +} + /* * Write open accounting is done only for sequential files. */ @@ -896,7 +934,7 @@ const struct file_operations zonefs_file_operations = { .llseek = zonefs_file_llseek, .read_iter = zonefs_file_read_iter, .write_iter = zonefs_file_write_iter, - .splice_read = generic_file_splice_read, + .splice_read = zonefs_file_splice_read, .splice_write = iter_file_splice_write, .iopoll = iocb_bio_iopoll, }; -- cgit v1.2.3-70-g09d2 From 5bd4990f19b0fedbba5511b44c1cd1fdb7061f3c Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:13 +0100 Subject: trace: Convert trace/seq to use copy_splice_read() For the splice from the trace seq buffer, just use copy_splice_read(). In the future, something better can probably be done by gifting pages from seq->buf into the pipe, but that would require changing seq->buf into a vmap over an array of pages. Signed-off-by: David Howells cc: Christoph Hellwig cc: Al Viro cc: Jens Axboe cc: Steven Rostedt cc: Masami Hiramatsu cc: linux-kernel@vger.kernel.org cc: linux-trace-kernel@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: linux-block@vger.kernel.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20230522135018.2742245-27-dhowells@redhat.com Signed-off-by: Jens Axboe --- kernel/trace/trace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index ebc59781456a..c210d02fac97 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -5171,7 +5171,7 @@ static const struct file_operations tracing_fops = { .open = tracing_open, .read = seq_read, .read_iter = seq_read_iter, - .splice_read = generic_file_splice_read, + .splice_read = copy_splice_read, .write = tracing_write_stub, .llseek = tracing_lseek, .release = tracing_release, -- cgit v1.2.3-70-g09d2 From ab82513126f8b426080038517b7d290adff377bb Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:14 +0100 Subject: cifs: Use filemap_splice_read() Make cifs use filemap_splice_read() rather than doing its own version of generic_file_splice_read(). Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: Paulo Alcantara (SUSE) cc: Jens Axboe cc: Steve French cc: Al Viro cc: David Hildenbrand cc: John Hubbard cc: linux-mm@kvack.org cc: linux-block@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20230522135018.2742245-28-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/cifs/cifsfs.c | 8 ++++---- fs/cifs/cifsfs.h | 3 --- fs/cifs/file.c | 16 ---------------- 3 files changed, 4 insertions(+), 23 deletions(-) diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index fa2477bbcc86..4f4492eb975f 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -1376,7 +1376,7 @@ const struct file_operations cifs_file_ops = { .fsync = cifs_fsync, .flush = cifs_flush, .mmap = cifs_file_mmap, - .splice_read = cifs_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, .llseek = cifs_llseek, .unlocked_ioctl = cifs_ioctl, @@ -1396,7 +1396,7 @@ const struct file_operations cifs_file_strict_ops = { .fsync = cifs_strict_fsync, .flush = cifs_flush, .mmap = cifs_file_strict_mmap, - .splice_read = cifs_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, .llseek = cifs_llseek, .unlocked_ioctl = cifs_ioctl, @@ -1434,7 +1434,7 @@ const struct file_operations cifs_file_nobrl_ops = { .fsync = cifs_fsync, .flush = cifs_flush, .mmap = cifs_file_mmap, - .splice_read = cifs_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, .llseek = cifs_llseek, .unlocked_ioctl = cifs_ioctl, @@ -1452,7 +1452,7 @@ const struct file_operations cifs_file_strict_nobrl_ops = { .fsync = cifs_strict_fsync, .flush = cifs_flush, .mmap = cifs_file_strict_mmap, - .splice_read = cifs_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, .llseek = cifs_llseek, .unlocked_ioctl = cifs_ioctl, diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h index 74cd6fafb33e..d7274eefc666 100644 --- a/fs/cifs/cifsfs.h +++ b/fs/cifs/cifsfs.h @@ -100,9 +100,6 @@ extern ssize_t cifs_strict_readv(struct kiocb *iocb, struct iov_iter *to); extern ssize_t cifs_user_writev(struct kiocb *iocb, struct iov_iter *from); extern ssize_t cifs_direct_writev(struct kiocb *iocb, struct iov_iter *from); extern ssize_t cifs_strict_writev(struct kiocb *iocb, struct iov_iter *from); -extern ssize_t cifs_splice_read(struct file *in, loff_t *ppos, - struct pipe_inode_info *pipe, size_t len, - unsigned int flags); extern int cifs_flock(struct file *pfile, int cmd, struct file_lock *plock); extern int cifs_lock(struct file *, int, struct file_lock *); extern int cifs_fsync(struct file *, loff_t, loff_t, int); diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 023496207c18..375a8037a3f3 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -5078,19 +5078,3 @@ const struct address_space_operations cifs_addr_ops_smallbuf = { .launder_folio = cifs_launder_folio, .migrate_folio = filemap_migrate_folio, }; - -/* - * Splice data from a file into a pipe. - */ -ssize_t cifs_splice_read(struct file *in, loff_t *ppos, - struct pipe_inode_info *pipe, size_t len, - unsigned int flags) -{ - if (unlikely(*ppos >= file_inode(in)->i_sb->s_maxbytes)) - return 0; - if (unlikely(!len)) - return 0; - if (in->f_flags & O_DIRECT) - return copy_splice_read(in, ppos, pipe, len, flags); - return filemap_splice_read(in, ppos, pipe, len, flags); -} -- cgit v1.2.3-70-g09d2 From 2cb1e08985e3dc59d0a4ebf770a87e3e2410d985 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:15 +0100 Subject: splice: Use filemap_splice_read() instead of generic_file_splice_read() Replace pointers to generic_file_splice_read() with calls to filemap_splice_read(). Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: Christian Brauner cc: Jens Axboe cc: Al Viro cc: David Hildenbrand cc: John Hubbard cc: linux-mm@kvack.org cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20230522135018.2742245-29-dhowells@redhat.com Signed-off-by: Jens Axboe --- block/fops.c | 2 +- fs/adfs/file.c | 2 +- fs/affs/file.c | 2 +- fs/afs/file.c | 2 +- fs/bfs/file.c | 2 +- fs/btrfs/file.c | 2 +- fs/cramfs/inode.c | 2 +- fs/ecryptfs/file.c | 4 ++-- fs/erofs/data.c | 2 +- fs/exfat/file.c | 2 +- fs/ext2/file.c | 2 +- fs/ext4/file.c | 2 +- fs/fat/file.c | 2 +- fs/fuse/file.c | 2 +- fs/gfs2/file.c | 4 ++-- fs/hfs/inode.c | 2 +- fs/hfsplus/inode.c | 2 +- fs/hostfs/hostfs_kern.c | 2 +- fs/hpfs/file.c | 2 +- fs/jffs2/file.c | 2 +- fs/jfs/file.c | 2 +- fs/minix/file.c | 2 +- fs/nilfs2/file.c | 2 +- fs/ntfs/file.c | 2 +- fs/ntfs3/file.c | 2 +- fs/ocfs2/file.c | 2 +- fs/omfs/file.c | 2 +- fs/ramfs/file-mmu.c | 2 +- fs/ramfs/file-nommu.c | 2 +- fs/read_write.c | 2 +- fs/reiserfs/file.c | 2 +- fs/romfs/mmap-nommu.c | 2 +- fs/sysv/file.c | 2 +- fs/ubifs/file.c | 2 +- fs/udf/file.c | 2 +- fs/ufs/file.c | 2 +- fs/vboxsf/file.c | 2 +- 37 files changed, 39 insertions(+), 39 deletions(-) diff --git a/block/fops.c b/block/fops.c index d2e6be4e3d1c..6c9aa028af6e 100644 --- a/block/fops.c +++ b/block/fops.c @@ -691,7 +691,7 @@ const struct file_operations def_blk_fops = { #ifdef CONFIG_COMPAT .compat_ioctl = compat_blkdev_ioctl, #endif - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, .fallocate = blkdev_fallocate, }; diff --git a/fs/adfs/file.c b/fs/adfs/file.c index 754afb14a6ff..ee80718aaeec 100644 --- a/fs/adfs/file.c +++ b/fs/adfs/file.c @@ -28,7 +28,7 @@ const struct file_operations adfs_file_operations = { .mmap = generic_file_mmap, .fsync = generic_file_fsync, .write_iter = generic_file_write_iter, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, }; const struct inode_operations adfs_file_inode_operations = { diff --git a/fs/affs/file.c b/fs/affs/file.c index 8daeed31e1af..e43f2f007ac1 100644 --- a/fs/affs/file.c +++ b/fs/affs/file.c @@ -1001,7 +1001,7 @@ const struct file_operations affs_file_operations = { .open = affs_file_open, .release = affs_file_release, .fsync = affs_file_fsync, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, }; const struct inode_operations affs_file_inode_operations = { diff --git a/fs/afs/file.c b/fs/afs/file.c index d8a6b09dadf7..d37dd201752b 100644 --- a/fs/afs/file.c +++ b/fs/afs/file.c @@ -603,5 +603,5 @@ static ssize_t afs_file_splice_read(struct file *in, loff_t *ppos, if (ret < 0) return ret; - return generic_file_splice_read(in, ppos, pipe, len, flags); + return filemap_splice_read(in, ppos, pipe, len, flags); } diff --git a/fs/bfs/file.c b/fs/bfs/file.c index 57ae5ee6deec..adc2230079c6 100644 --- a/fs/bfs/file.c +++ b/fs/bfs/file.c @@ -27,7 +27,7 @@ const struct file_operations bfs_file_operations = { .read_iter = generic_file_read_iter, .write_iter = generic_file_write_iter, .mmap = generic_file_mmap, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, }; static int bfs_move_block(unsigned long from, unsigned long to, diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index f649647392e0..71426c6408fa 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -3825,7 +3825,7 @@ static ssize_t btrfs_file_read_iter(struct kiocb *iocb, struct iov_iter *to) const struct file_operations btrfs_file_operations = { .llseek = btrfs_file_llseek, .read_iter = btrfs_file_read_iter, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .write_iter = btrfs_file_write_iter, .splice_write = iter_file_splice_write, .mmap = btrfs_file_mmap, diff --git a/fs/cramfs/inode.c b/fs/cramfs/inode.c index 006ef68d7ff6..27c6597aa1be 100644 --- a/fs/cramfs/inode.c +++ b/fs/cramfs/inode.c @@ -473,7 +473,7 @@ static unsigned int cramfs_physmem_mmap_capabilities(struct file *file) static const struct file_operations cramfs_physmem_fops = { .llseek = generic_file_llseek, .read_iter = generic_file_read_iter, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .mmap = cramfs_physmem_mmap, #ifndef CONFIG_MMU .get_unmapped_area = cramfs_physmem_get_unmapped_area, diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c index 284395587be0..ce0a3c5ed0ca 100644 --- a/fs/ecryptfs/file.c +++ b/fs/ecryptfs/file.c @@ -47,7 +47,7 @@ static ssize_t ecryptfs_read_update_atime(struct kiocb *iocb, /* * ecryptfs_splice_read_update_atime * - * generic_file_splice_read updates the atime of upper layer inode. But, it + * filemap_splice_read updates the atime of upper layer inode. But, it * doesn't give us a chance to update the atime of the lower layer inode. This * function is a wrapper to generic_file_read. It updates the atime of the * lower level inode if generic_file_read returns without any errors. This is @@ -61,7 +61,7 @@ static ssize_t ecryptfs_splice_read_update_atime(struct file *in, loff_t *ppos, ssize_t rc; const struct path *path; - rc = generic_file_splice_read(in, ppos, pipe, len, flags); + rc = filemap_splice_read(in, ppos, pipe, len, flags); if (rc >= 0) { path = ecryptfs_dentry_to_lower_path(in->f_path.dentry); touch_atime(path); diff --git a/fs/erofs/data.c b/fs/erofs/data.c index 6fe9a779fa91..db5e4b7636ec 100644 --- a/fs/erofs/data.c +++ b/fs/erofs/data.c @@ -448,5 +448,5 @@ const struct file_operations erofs_file_fops = { .llseek = generic_file_llseek, .read_iter = erofs_file_read_iter, .mmap = erofs_file_mmap, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, }; diff --git a/fs/exfat/file.c b/fs/exfat/file.c index e99183a74611..3cbd270e0cba 100644 --- a/fs/exfat/file.c +++ b/fs/exfat/file.c @@ -389,7 +389,7 @@ const struct file_operations exfat_file_operations = { #endif .mmap = generic_file_mmap, .fsync = exfat_file_fsync, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, }; diff --git a/fs/ext2/file.c b/fs/ext2/file.c index 6b4bebe982ca..d1ae0f0a3726 100644 --- a/fs/ext2/file.c +++ b/fs/ext2/file.c @@ -192,7 +192,7 @@ const struct file_operations ext2_file_operations = { .release = ext2_release_file, .fsync = ext2_fsync, .get_unmapped_area = thp_get_unmapped_area, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, }; diff --git a/fs/ext4/file.c b/fs/ext4/file.c index 9f8bbd9d131c..e8261900f4f3 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -155,7 +155,7 @@ static ssize_t ext4_file_splice_read(struct file *in, loff_t *ppos, if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) return -EIO; - return generic_file_splice_read(in, ppos, pipe, len, flags); + return filemap_splice_read(in, ppos, pipe, len, flags); } /* diff --git a/fs/fat/file.c b/fs/fat/file.c index 795a4fad5c40..456477946dd9 100644 --- a/fs/fat/file.c +++ b/fs/fat/file.c @@ -209,7 +209,7 @@ const struct file_operations fat_file_operations = { .unlocked_ioctl = fat_generic_ioctl, .compat_ioctl = compat_ptr_ioctl, .fsync = fat_file_fsync, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, .fallocate = fat_fallocate, }; diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 89d97f6188e0..4553124f5406 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -3252,7 +3252,7 @@ static const struct file_operations fuse_file_operations = { .lock = fuse_file_lock, .get_unmapped_area = thp_get_unmapped_area, .flock = fuse_file_flock, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, .unlocked_ioctl = fuse_file_ioctl, .compat_ioctl = fuse_file_compat_ioctl, diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c index 300844f50dcd..0f5ad5165361 100644 --- a/fs/gfs2/file.c +++ b/fs/gfs2/file.c @@ -1568,7 +1568,7 @@ const struct file_operations gfs2_file_fops = { .fsync = gfs2_fsync, .lock = gfs2_lock, .flock = gfs2_flock, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .splice_write = gfs2_file_splice_write, .setlease = simple_nosetlease, .fallocate = gfs2_fallocate, @@ -1599,7 +1599,7 @@ const struct file_operations gfs2_file_fops_nolock = { .open = gfs2_open, .release = gfs2_release, .fsync = gfs2_fsync, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .splice_write = gfs2_file_splice_write, .setlease = generic_setlease, .fallocate = gfs2_fallocate, diff --git a/fs/hfs/inode.c b/fs/hfs/inode.c index 1f7bd068acf0..441d7fc952e3 100644 --- a/fs/hfs/inode.c +++ b/fs/hfs/inode.c @@ -694,7 +694,7 @@ static const struct file_operations hfs_file_operations = { .read_iter = generic_file_read_iter, .write_iter = generic_file_write_iter, .mmap = generic_file_mmap, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .fsync = hfs_file_fsync, .open = hfs_file_open, .release = hfs_file_release, diff --git a/fs/hfsplus/inode.c b/fs/hfsplus/inode.c index b21660475ac1..7d1a675e037d 100644 --- a/fs/hfsplus/inode.c +++ b/fs/hfsplus/inode.c @@ -372,7 +372,7 @@ static const struct file_operations hfsplus_file_operations = { .read_iter = generic_file_read_iter, .write_iter = generic_file_write_iter, .mmap = generic_file_mmap, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .fsync = hfsplus_file_fsync, .open = hfsplus_file_open, .release = hfsplus_file_release, diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c index 28b4f15c19eb..87998df499f4 100644 --- a/fs/hostfs/hostfs_kern.c +++ b/fs/hostfs/hostfs_kern.c @@ -381,7 +381,7 @@ static int hostfs_fsync(struct file *file, loff_t start, loff_t end, static const struct file_operations hostfs_file_fops = { .llseek = generic_file_llseek, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, .read_iter = generic_file_read_iter, .write_iter = generic_file_write_iter, diff --git a/fs/hpfs/file.c b/fs/hpfs/file.c index 88952d4a631e..1bb8d97cd9ae 100644 --- a/fs/hpfs/file.c +++ b/fs/hpfs/file.c @@ -259,7 +259,7 @@ const struct file_operations hpfs_file_ops = .mmap = generic_file_mmap, .release = hpfs_file_release, .fsync = hpfs_file_fsync, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .unlocked_ioctl = hpfs_ioctl, .compat_ioctl = compat_ptr_ioctl, }; diff --git a/fs/jffs2/file.c b/fs/jffs2/file.c index 96b0275ce957..2345ca3f09ee 100644 --- a/fs/jffs2/file.c +++ b/fs/jffs2/file.c @@ -56,7 +56,7 @@ const struct file_operations jffs2_file_operations = .unlocked_ioctl=jffs2_ioctl, .mmap = generic_file_readonly_mmap, .fsync = jffs2_fsync, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, }; diff --git a/fs/jfs/file.c b/fs/jfs/file.c index 2ee35be49de1..01b6912e60f8 100644 --- a/fs/jfs/file.c +++ b/fs/jfs/file.c @@ -144,7 +144,7 @@ const struct file_operations jfs_file_operations = { .read_iter = generic_file_read_iter, .write_iter = generic_file_write_iter, .mmap = generic_file_mmap, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, .fsync = jfs_fsync, .release = jfs_release, diff --git a/fs/minix/file.c b/fs/minix/file.c index 0dd05d47724a..906d192ab7f3 100644 --- a/fs/minix/file.c +++ b/fs/minix/file.c @@ -19,7 +19,7 @@ const struct file_operations minix_file_operations = { .write_iter = generic_file_write_iter, .mmap = generic_file_mmap, .fsync = generic_file_fsync, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, }; static int minix_setattr(struct mnt_idmap *idmap, diff --git a/fs/nilfs2/file.c b/fs/nilfs2/file.c index a265d391ffe9..a9eb3487efb2 100644 --- a/fs/nilfs2/file.c +++ b/fs/nilfs2/file.c @@ -140,7 +140,7 @@ const struct file_operations nilfs_file_operations = { .open = generic_file_open, /* .release = nilfs_release_file, */ .fsync = nilfs_sync_file, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, }; diff --git a/fs/ntfs/file.c b/fs/ntfs/file.c index c481b14e4fd9..e5e0ed58670b 100644 --- a/fs/ntfs/file.c +++ b/fs/ntfs/file.c @@ -1992,7 +1992,7 @@ const struct file_operations ntfs_file_ops = { #endif /* NTFS_RW */ .mmap = generic_file_mmap, .open = ntfs_file_open, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, }; const struct inode_operations ntfs_file_inode_ops = { diff --git a/fs/ntfs3/file.c b/fs/ntfs3/file.c index 667c9dc68b58..036efd85f60c 100644 --- a/fs/ntfs3/file.c +++ b/fs/ntfs3/file.c @@ -770,7 +770,7 @@ static ssize_t ntfs_file_splice_read(struct file *in, loff_t *ppos, return -EOPNOTSUPP; } - return generic_file_splice_read(in, ppos, pipe, len, flags); + return filemap_splice_read(in, ppos, pipe, len, flags); } /* diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c index 86add13b5f23..42549fc81468 100644 --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -2827,7 +2827,7 @@ const struct file_operations ocfs2_fops_no_plocks = { .compat_ioctl = ocfs2_compat_ioctl, #endif .flock = ocfs2_flock, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, .fallocate = ocfs2_fallocate, .remap_file_range = ocfs2_remap_file_range, diff --git a/fs/omfs/file.c b/fs/omfs/file.c index 0101f1f87b56..de8f57ee39ec 100644 --- a/fs/omfs/file.c +++ b/fs/omfs/file.c @@ -334,7 +334,7 @@ const struct file_operations omfs_file_operations = { .write_iter = generic_file_write_iter, .mmap = generic_file_mmap, .fsync = generic_file_fsync, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, }; static int omfs_setattr(struct mnt_idmap *idmap, diff --git a/fs/ramfs/file-mmu.c b/fs/ramfs/file-mmu.c index 12af0490322f..c7a1aa3c882b 100644 --- a/fs/ramfs/file-mmu.c +++ b/fs/ramfs/file-mmu.c @@ -43,7 +43,7 @@ const struct file_operations ramfs_file_operations = { .write_iter = generic_file_write_iter, .mmap = generic_file_mmap, .fsync = noop_fsync, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, .llseek = generic_file_llseek, .get_unmapped_area = ramfs_mmu_get_unmapped_area, diff --git a/fs/ramfs/file-nommu.c b/fs/ramfs/file-nommu.c index 9fbb9b5256f7..efb1b4c1a0a4 100644 --- a/fs/ramfs/file-nommu.c +++ b/fs/ramfs/file-nommu.c @@ -43,7 +43,7 @@ const struct file_operations ramfs_file_operations = { .read_iter = generic_file_read_iter, .write_iter = generic_file_write_iter, .fsync = noop_fsync, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, .llseek = generic_file_llseek, }; diff --git a/fs/read_write.c b/fs/read_write.c index a21ba3be7dbe..b07de77ef126 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -29,7 +29,7 @@ const struct file_operations generic_ro_fops = { .llseek = generic_file_llseek, .read_iter = generic_file_read_iter, .mmap = generic_file_readonly_mmap, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, }; EXPORT_SYMBOL(generic_ro_fops); diff --git a/fs/reiserfs/file.c b/fs/reiserfs/file.c index b54cc7048f02..8eb3ad3e8ae9 100644 --- a/fs/reiserfs/file.c +++ b/fs/reiserfs/file.c @@ -247,7 +247,7 @@ const struct file_operations reiserfs_file_operations = { .fsync = reiserfs_sync_file, .read_iter = generic_file_read_iter, .write_iter = generic_file_write_iter, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, .llseek = generic_file_llseek, }; diff --git a/fs/romfs/mmap-nommu.c b/fs/romfs/mmap-nommu.c index 4578dc45e50a..4520ca413867 100644 --- a/fs/romfs/mmap-nommu.c +++ b/fs/romfs/mmap-nommu.c @@ -78,7 +78,7 @@ static unsigned romfs_mmap_capabilities(struct file *file) const struct file_operations romfs_ro_fops = { .llseek = generic_file_llseek, .read_iter = generic_file_read_iter, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .mmap = romfs_mmap, .get_unmapped_area = romfs_get_unmapped_area, .mmap_capabilities = romfs_mmap_capabilities, diff --git a/fs/sysv/file.c b/fs/sysv/file.c index 50eb92557a0f..c645f60bdb7f 100644 --- a/fs/sysv/file.c +++ b/fs/sysv/file.c @@ -26,7 +26,7 @@ const struct file_operations sysv_file_operations = { .write_iter = generic_file_write_iter, .mmap = generic_file_mmap, .fsync = generic_file_fsync, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, }; static int sysv_setattr(struct mnt_idmap *idmap, diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c index 979ab1d9d0c3..6738fe43040b 100644 --- a/fs/ubifs/file.c +++ b/fs/ubifs/file.c @@ -1669,7 +1669,7 @@ const struct file_operations ubifs_file_operations = { .mmap = ubifs_file_mmap, .fsync = ubifs_fsync, .unlocked_ioctl = ubifs_ioctl, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, .open = fscrypt_file_open, #ifdef CONFIG_COMPAT diff --git a/fs/udf/file.c b/fs/udf/file.c index 8238f742377b..29daf5d5cb67 100644 --- a/fs/udf/file.c +++ b/fs/udf/file.c @@ -209,7 +209,7 @@ const struct file_operations udf_file_operations = { .write_iter = udf_file_write_iter, .release = udf_release_file, .fsync = generic_file_fsync, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, .splice_write = iter_file_splice_write, .llseek = generic_file_llseek, }; diff --git a/fs/ufs/file.c b/fs/ufs/file.c index 7e087581be7e..6558882a89ef 100644 --- a/fs/ufs/file.c +++ b/fs/ufs/file.c @@ -41,5 +41,5 @@ const struct file_operations ufs_file_operations = { .mmap = generic_file_mmap, .open = generic_file_open, .fsync = generic_file_fsync, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, }; diff --git a/fs/vboxsf/file.c b/fs/vboxsf/file.c index 572aa1c43b37..2307f8037efc 100644 --- a/fs/vboxsf/file.c +++ b/fs/vboxsf/file.c @@ -217,7 +217,7 @@ const struct file_operations vboxsf_reg_fops = { .open = vboxsf_file_open, .release = vboxsf_file_release, .fsync = noop_fsync, - .splice_read = generic_file_splice_read, + .splice_read = filemap_splice_read, }; const struct inode_operations vboxsf_reg_iops = { -- cgit v1.2.3-70-g09d2 From c6585011bc1d8934cc78046c50fc94590fb2ab24 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:16 +0100 Subject: splice: Remove generic_file_splice_read() Remove generic_file_splice_read() as it has been replaced with calls to filemap_splice_read() and copy_splice_read(). With this, ITER_PIPE is no longer used. Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: Christian Brauner cc: Jens Axboe cc: Steve French cc: Al Viro cc: David Hildenbrand cc: John Hubbard cc: linux-mm@kvack.org cc: linux-block@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20230522135018.2742245-30-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/splice.c | 43 ------------------------------------------- include/linux/fs.h | 2 -- 2 files changed, 45 deletions(-) diff --git a/fs/splice.c b/fs/splice.c index 8268248df3a9..9be4cb3b9879 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -386,49 +386,6 @@ ssize_t copy_splice_read(struct file *in, loff_t *ppos, } EXPORT_SYMBOL(copy_splice_read); -/** - * generic_file_splice_read - splice data from file to a pipe - * @in: file to splice from - * @ppos: position in @in - * @pipe: pipe to splice to - * @len: number of bytes to splice - * @flags: splice modifier flags - * - * Description: - * Will read pages from given file and fill them into a pipe. Can be - * 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) -{ - struct iov_iter to; - struct kiocb kiocb; - int ret; - - iov_iter_pipe(&to, ITER_DEST, pipe, len); - init_sync_kiocb(&kiocb, in); - kiocb.ki_pos = *ppos; - ret = call_read_iter(in, &kiocb, &to); - if (ret > 0) { - *ppos = kiocb.ki_pos; - file_accessed(in); - } else if (ret < 0) { - /* free what was emitted */ - pipe_discard_from(pipe, to.start_head); - /* - * 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); - const struct pipe_buf_operations default_pipe_buf_ops = { .release = generic_pipe_buf_release, .try_steal = generic_pipe_buf_try_steal, diff --git a/include/linux/fs.h b/include/linux/fs.h index e3c22efa413e..08ba2ae1d3ce 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2755,8 +2755,6 @@ ssize_t filemap_splice_read(struct file *in, loff_t *ppos, ssize_t copy_splice_read(struct file *in, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags); -extern ssize_t generic_file_splice_read(struct file *, loff_t *, - struct pipe_inode_info *, size_t, unsigned int); extern ssize_t iter_file_splice_write(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int); extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe, -- cgit v1.2.3-70-g09d2 From 3fc40265ae2b48a7475c41c5c0b256374c419f4b Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:17 +0100 Subject: iov_iter: Kill ITER_PIPE The ITER_PIPE-type iterator was only used by generic_file_splice_read() and that has been replaced and removed. This leaves ITER_PIPE unused - so remove it too. Signed-off-by: David Howells Reviewed-by: Christoph Hellwig Reviewed-by: Christian Brauner cc: Jens Axboe cc: Al Viro cc: David Hildenbrand cc: John Hubbard cc: linux-mm@kvack.org cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20230522135018.2742245-31-dhowells@redhat.com Signed-off-by: Jens Axboe --- include/linux/uio.h | 14 -- lib/iov_iter.c | 431 +--------------------------------------------------- mm/filemap.c | 3 +- 3 files changed, 4 insertions(+), 444 deletions(-) diff --git a/include/linux/uio.h b/include/linux/uio.h index 044c1d8c230c..60c342bb7ab8 100644 --- a/include/linux/uio.h +++ b/include/linux/uio.h @@ -11,7 +11,6 @@ #include struct page; -struct pipe_inode_info; typedef unsigned int __bitwise iov_iter_extraction_t; @@ -25,7 +24,6 @@ enum iter_type { ITER_IOVEC, ITER_KVEC, ITER_BVEC, - ITER_PIPE, ITER_XARRAY, ITER_DISCARD, ITER_UBUF, @@ -74,7 +72,6 @@ struct iov_iter { const struct kvec *kvec; const struct bio_vec *bvec; struct xarray *xarray; - struct pipe_inode_info *pipe; void __user *ubuf; }; size_t count; @@ -82,10 +79,6 @@ struct iov_iter { }; union { unsigned long nr_segs; - struct { - unsigned int head; - unsigned int start_head; - }; loff_t xarray_start; }; }; @@ -133,11 +126,6 @@ static inline bool iov_iter_is_bvec(const struct iov_iter *i) return iov_iter_type(i) == ITER_BVEC; } -static inline bool iov_iter_is_pipe(const struct iov_iter *i) -{ - return iov_iter_type(i) == ITER_PIPE; -} - static inline bool iov_iter_is_discard(const struct iov_iter *i) { return iov_iter_type(i) == ITER_DISCARD; @@ -286,8 +274,6 @@ void iov_iter_kvec(struct iov_iter *i, unsigned int direction, const struct kvec unsigned long nr_segs, size_t count); void iov_iter_bvec(struct iov_iter *i, unsigned int direction, const struct bio_vec *bvec, unsigned long nr_segs, size_t count); -void iov_iter_pipe(struct iov_iter *i, unsigned int direction, struct pipe_inode_info *pipe, - size_t count); void iov_iter_discard(struct iov_iter *i, unsigned int direction, size_t count); void iov_iter_xarray(struct iov_iter *i, unsigned int direction, struct xarray *xarray, loff_t start, size_t count); diff --git a/lib/iov_iter.c b/lib/iov_iter.c index 960223ed9199..f18138e0292a 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -14,8 +14,6 @@ #include #include -#define PIPE_PARANOIA /* for now */ - /* covers ubuf and kbuf alike */ #define iterate_buf(i, n, base, len, off, __p, STEP) { \ size_t __maybe_unused off = 0; \ @@ -198,150 +196,6 @@ static int copyin(void *to, const void __user *from, size_t n) return res; } -#ifdef PIPE_PARANOIA -static bool sanity(const struct iov_iter *i) -{ - struct pipe_inode_info *pipe = i->pipe; - unsigned int p_head = pipe->head; - unsigned int p_tail = pipe->tail; - unsigned int p_occupancy = pipe_occupancy(p_head, p_tail); - unsigned int i_head = i->head; - unsigned int idx; - - if (i->last_offset) { - struct pipe_buffer *p; - if (unlikely(p_occupancy == 0)) - goto Bad; // pipe must be non-empty - if (unlikely(i_head != p_head - 1)) - goto Bad; // must be at the last buffer... - - p = pipe_buf(pipe, i_head); - if (unlikely(p->offset + p->len != abs(i->last_offset))) - goto Bad; // ... at the end of segment - } else { - if (i_head != p_head) - goto Bad; // must be right after the last buffer - } - return true; -Bad: - printk(KERN_ERR "idx = %d, offset = %d\n", i_head, i->last_offset); - printk(KERN_ERR "head = %d, tail = %d, buffers = %d\n", - p_head, p_tail, pipe->ring_size); - for (idx = 0; idx < pipe->ring_size; idx++) - printk(KERN_ERR "[%p %p %d %d]\n", - pipe->bufs[idx].ops, - pipe->bufs[idx].page, - pipe->bufs[idx].offset, - pipe->bufs[idx].len); - WARN_ON(1); - return false; -} -#else -#define sanity(i) true -#endif - -static struct page *push_anon(struct pipe_inode_info *pipe, unsigned size) -{ - struct page *page = alloc_page(GFP_USER); - if (page) { - struct pipe_buffer *buf = pipe_buf(pipe, pipe->head++); - *buf = (struct pipe_buffer) { - .ops = &default_pipe_buf_ops, - .page = page, - .offset = 0, - .len = size - }; - } - return page; -} - -static void push_page(struct pipe_inode_info *pipe, struct page *page, - unsigned int offset, unsigned int size) -{ - struct pipe_buffer *buf = pipe_buf(pipe, pipe->head++); - *buf = (struct pipe_buffer) { - .ops = &page_cache_pipe_buf_ops, - .page = page, - .offset = offset, - .len = size - }; - get_page(page); -} - -static inline int last_offset(const struct pipe_buffer *buf) -{ - if (buf->ops == &default_pipe_buf_ops) - return buf->len; // buf->offset is 0 for those - else - return -(buf->offset + buf->len); -} - -static struct page *append_pipe(struct iov_iter *i, size_t size, - unsigned int *off) -{ - struct pipe_inode_info *pipe = i->pipe; - int offset = i->last_offset; - struct pipe_buffer *buf; - struct page *page; - - if (offset > 0 && offset < PAGE_SIZE) { - // some space in the last buffer; add to it - buf = pipe_buf(pipe, pipe->head - 1); - size = min_t(size_t, size, PAGE_SIZE - offset); - buf->len += size; - i->last_offset += size; - i->count -= size; - *off = offset; - return buf->page; - } - // OK, we need a new buffer - *off = 0; - size = min_t(size_t, size, PAGE_SIZE); - if (pipe_full(pipe->head, pipe->tail, pipe->max_usage)) - return NULL; - page = push_anon(pipe, size); - if (!page) - return NULL; - i->head = pipe->head - 1; - i->last_offset = size; - i->count -= size; - return page; -} - -static size_t copy_page_to_iter_pipe(struct page *page, size_t offset, size_t bytes, - struct iov_iter *i) -{ - struct pipe_inode_info *pipe = i->pipe; - unsigned int head = pipe->head; - - if (unlikely(bytes > i->count)) - bytes = i->count; - - if (unlikely(!bytes)) - return 0; - - if (!sanity(i)) - return 0; - - if (offset && i->last_offset == -offset) { // could we merge it? - struct pipe_buffer *buf = pipe_buf(pipe, head - 1); - if (buf->page == page) { - buf->len += bytes; - i->last_offset -= bytes; - i->count -= bytes; - return bytes; - } - } - if (pipe_full(pipe->head, pipe->tail, pipe->max_usage)) - return 0; - - push_page(pipe, page, offset, bytes); - i->last_offset = -(offset + bytes); - i->head = head; - i->count -= bytes; - return bytes; -} - /* * fault_in_iov_iter_readable - fault in iov iterator for reading * @i: iterator @@ -446,46 +300,6 @@ void iov_iter_init(struct iov_iter *i, unsigned int direction, } EXPORT_SYMBOL(iov_iter_init); -// returns the offset in partial buffer (if any) -static inline unsigned int pipe_npages(const struct iov_iter *i, int *npages) -{ - struct pipe_inode_info *pipe = i->pipe; - int used = pipe->head - pipe->tail; - int off = i->last_offset; - - *npages = max((int)pipe->max_usage - used, 0); - - if (off > 0 && off < PAGE_SIZE) { // anon and not full - (*npages)++; - return off; - } - return 0; -} - -static size_t copy_pipe_to_iter(const void *addr, size_t bytes, - struct iov_iter *i) -{ - unsigned int off, chunk; - - if (unlikely(bytes > i->count)) - bytes = i->count; - if (unlikely(!bytes)) - return 0; - - if (!sanity(i)) - return 0; - - for (size_t n = bytes; n; n -= chunk) { - struct page *page = append_pipe(i, n, &off); - chunk = min_t(size_t, n, PAGE_SIZE - off); - if (!page) - return bytes - n; - memcpy_to_page(page, off, addr, chunk); - addr += chunk; - } - return bytes; -} - static __wsum csum_and_memcpy(void *to, const void *from, size_t len, __wsum sum, size_t off) { @@ -493,44 +307,10 @@ static __wsum csum_and_memcpy(void *to, const void *from, size_t len, return csum_block_add(sum, next, off); } -static size_t csum_and_copy_to_pipe_iter(const void *addr, size_t bytes, - struct iov_iter *i, __wsum *sump) -{ - __wsum sum = *sump; - size_t off = 0; - unsigned int chunk, r; - - if (unlikely(bytes > i->count)) - bytes = i->count; - if (unlikely(!bytes)) - return 0; - - if (!sanity(i)) - return 0; - - while (bytes) { - struct page *page = append_pipe(i, bytes, &r); - char *p; - - if (!page) - break; - chunk = min_t(size_t, bytes, PAGE_SIZE - r); - p = kmap_local_page(page); - sum = csum_and_memcpy(p + r, addr + off, chunk, sum, off); - kunmap_local(p); - off += chunk; - bytes -= chunk; - } - *sump = sum; - return off; -} - size_t _copy_to_iter(const void *addr, size_t bytes, struct iov_iter *i) { if (WARN_ON_ONCE(i->data_source)) return 0; - if (unlikely(iov_iter_is_pipe(i))) - return copy_pipe_to_iter(addr, bytes, i); if (user_backed_iter(i)) might_fault(); iterate_and_advance(i, bytes, base, len, off, @@ -552,42 +332,6 @@ static int copyout_mc(void __user *to, const void *from, size_t n) return n; } -static size_t copy_mc_pipe_to_iter(const void *addr, size_t bytes, - struct iov_iter *i) -{ - size_t xfer = 0; - unsigned int off, chunk; - - if (unlikely(bytes > i->count)) - bytes = i->count; - if (unlikely(!bytes)) - return 0; - - if (!sanity(i)) - return 0; - - while (bytes) { - struct page *page = append_pipe(i, bytes, &off); - unsigned long rem; - char *p; - - if (!page) - break; - chunk = min_t(size_t, bytes, PAGE_SIZE - off); - p = kmap_local_page(page); - rem = copy_mc_to_kernel(p + off, addr + xfer, chunk); - chunk -= rem; - kunmap_local(p); - xfer += chunk; - bytes -= chunk; - if (rem) { - iov_iter_revert(i, rem); - break; - } - } - return xfer; -} - /** * _copy_mc_to_iter - copy to iter with source memory error exception handling * @addr: source kernel address @@ -607,9 +351,8 @@ static size_t copy_mc_pipe_to_iter(const void *addr, size_t bytes, * alignment and poison alignment assumptions to avoid re-triggering * hardware exceptions. * - * * ITER_KVEC, ITER_PIPE, and ITER_BVEC can return short copies. - * Compare to copy_to_iter() where only ITER_IOVEC attempts might return - * a short copy. + * * ITER_KVEC and ITER_BVEC can return short copies. Compare to + * copy_to_iter() where only ITER_IOVEC attempts might return a short copy. * * Return: number of bytes copied (may be %0) */ @@ -617,8 +360,6 @@ size_t _copy_mc_to_iter(const void *addr, size_t bytes, struct iov_iter *i) { if (WARN_ON_ONCE(i->data_source)) return 0; - if (unlikely(iov_iter_is_pipe(i))) - return copy_mc_pipe_to_iter(addr, bytes, i); if (user_backed_iter(i)) might_fault(); __iterate_and_advance(i, bytes, base, len, off, @@ -732,8 +473,6 @@ size_t copy_page_to_iter(struct page *page, size_t offset, size_t bytes, return 0; if (WARN_ON_ONCE(i->data_source)) return 0; - if (unlikely(iov_iter_is_pipe(i))) - return copy_page_to_iter_pipe(page, offset, bytes, i); page += offset / PAGE_SIZE; // first subpage offset %= PAGE_SIZE; while (1) { @@ -764,8 +503,6 @@ size_t copy_page_to_iter_nofault(struct page *page, unsigned offset, size_t byte return 0; if (WARN_ON_ONCE(i->data_source)) return 0; - if (unlikely(iov_iter_is_pipe(i))) - return copy_page_to_iter_pipe(page, offset, bytes, i); page += offset / PAGE_SIZE; // first subpage offset %= PAGE_SIZE; while (1) { @@ -818,36 +555,8 @@ size_t copy_page_from_iter(struct page *page, size_t offset, size_t bytes, } EXPORT_SYMBOL(copy_page_from_iter); -static size_t pipe_zero(size_t bytes, struct iov_iter *i) -{ - unsigned int chunk, off; - - if (unlikely(bytes > i->count)) - bytes = i->count; - if (unlikely(!bytes)) - return 0; - - if (!sanity(i)) - return 0; - - for (size_t n = bytes; n; n -= chunk) { - struct page *page = append_pipe(i, n, &off); - char *p; - - if (!page) - return bytes - n; - chunk = min_t(size_t, n, PAGE_SIZE - off); - p = kmap_local_page(page); - memset(p + off, 0, chunk); - kunmap_local(p); - } - return bytes; -} - size_t iov_iter_zero(size_t bytes, struct iov_iter *i) { - if (unlikely(iov_iter_is_pipe(i))) - return pipe_zero(bytes, i); iterate_and_advance(i, bytes, base, len, count, clear_user(base, len), memset(base, 0, len) @@ -878,32 +587,6 @@ size_t copy_page_from_iter_atomic(struct page *page, unsigned offset, size_t byt } EXPORT_SYMBOL(copy_page_from_iter_atomic); -static void pipe_advance(struct iov_iter *i, size_t size) -{ - struct pipe_inode_info *pipe = i->pipe; - int off = i->last_offset; - - if (!off && !size) { - pipe_discard_from(pipe, i->start_head); // discard everything - return; - } - i->count -= size; - while (1) { - struct pipe_buffer *buf = pipe_buf(pipe, i->head); - if (off) /* make it relative to the beginning of buffer */ - size += abs(off) - buf->offset; - if (size <= buf->len) { - buf->len = size; - i->last_offset = last_offset(buf); - break; - } - size -= buf->len; - i->head++; - off = 0; - } - pipe_discard_from(pipe, i->head + 1); // discard everything past this one -} - static void iov_iter_bvec_advance(struct iov_iter *i, size_t size) { const struct bio_vec *bvec, *end; @@ -955,8 +638,6 @@ void iov_iter_advance(struct iov_iter *i, size_t size) iov_iter_iovec_advance(i, size); } else if (iov_iter_is_bvec(i)) { iov_iter_bvec_advance(i, size); - } else if (iov_iter_is_pipe(i)) { - pipe_advance(i, size); } else if (iov_iter_is_discard(i)) { i->count -= size; } @@ -970,26 +651,6 @@ void iov_iter_revert(struct iov_iter *i, size_t unroll) if (WARN_ON(unroll > MAX_RW_COUNT)) return; i->count += unroll; - if (unlikely(iov_iter_is_pipe(i))) { - struct pipe_inode_info *pipe = i->pipe; - unsigned int head = pipe->head; - - while (head > i->start_head) { - struct pipe_buffer *b = pipe_buf(pipe, --head); - if (unroll < b->len) { - b->len -= unroll; - i->last_offset = last_offset(b); - i->head = head; - return; - } - unroll -= b->len; - pipe_buf_release(pipe, b); - pipe->head--; - } - i->last_offset = 0; - i->head = head; - return; - } if (unlikely(iov_iter_is_discard(i))) return; if (unroll <= i->iov_offset) { @@ -1079,24 +740,6 @@ void iov_iter_bvec(struct iov_iter *i, unsigned int direction, } EXPORT_SYMBOL(iov_iter_bvec); -void iov_iter_pipe(struct iov_iter *i, unsigned int direction, - struct pipe_inode_info *pipe, - size_t count) -{ - BUG_ON(direction != READ); - WARN_ON(pipe_full(pipe->head, pipe->tail, pipe->ring_size)); - *i = (struct iov_iter){ - .iter_type = ITER_PIPE, - .data_source = false, - .pipe = pipe, - .head = pipe->head, - .start_head = pipe->head, - .last_offset = 0, - .count = count - }; -} -EXPORT_SYMBOL(iov_iter_pipe); - /** * iov_iter_xarray - Initialise an I/O iterator to use the pages in an xarray * @i: The iterator to initialise. @@ -1224,19 +867,6 @@ bool iov_iter_is_aligned(const struct iov_iter *i, unsigned addr_mask, if (iov_iter_is_bvec(i)) return iov_iter_aligned_bvec(i, addr_mask, len_mask); - if (iov_iter_is_pipe(i)) { - size_t size = i->count; - - if (size & len_mask) - return false; - if (size && i->last_offset > 0) { - if (i->last_offset & addr_mask) - return false; - } - - return true; - } - if (iov_iter_is_xarray(i)) { if (i->count & len_mask) return false; @@ -1307,14 +937,6 @@ unsigned long iov_iter_alignment(const struct iov_iter *i) if (iov_iter_is_bvec(i)) return iov_iter_alignment_bvec(i); - if (iov_iter_is_pipe(i)) { - size_t size = i->count; - - if (size && i->last_offset > 0) - return size | i->last_offset; - return size; - } - if (iov_iter_is_xarray(i)) return (i->xarray_start + i->iov_offset) | i->count; @@ -1367,36 +989,6 @@ static int want_pages_array(struct page ***res, size_t size, return count; } -static ssize_t pipe_get_pages(struct iov_iter *i, - struct page ***pages, size_t maxsize, unsigned maxpages, - size_t *start) -{ - unsigned int npages, count, off, chunk; - struct page **p; - size_t left; - - if (!sanity(i)) - return -EFAULT; - - *start = off = pipe_npages(i, &npages); - if (!npages) - return -EFAULT; - count = want_pages_array(pages, maxsize, off, min(npages, maxpages)); - if (!count) - return -ENOMEM; - p = *pages; - for (npages = 0, left = maxsize ; npages < count; npages++, left -= chunk) { - struct page *page = append_pipe(i, left, &off); - if (!page) - break; - chunk = min_t(size_t, left, PAGE_SIZE - off); - get_page(*p++ = page); - } - if (!npages) - return -EFAULT; - return maxsize - left; -} - static ssize_t iter_xarray_populate_pages(struct page **pages, struct xarray *xa, pgoff_t index, unsigned int nr_pages) { @@ -1547,8 +1139,6 @@ static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i, } return maxsize; } - if (iov_iter_is_pipe(i)) - return pipe_get_pages(i, pages, maxsize, maxpages, start); if (iov_iter_is_xarray(i)) return iter_xarray_get_pages(i, pages, maxsize, maxpages, start); return -EFAULT; @@ -1638,9 +1228,7 @@ size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *_csstate, } sum = csum_shift(csstate->csum, csstate->off); - if (unlikely(iov_iter_is_pipe(i))) - bytes = csum_and_copy_to_pipe_iter(addr, bytes, i, &sum); - else iterate_and_advance(i, bytes, base, len, off, ({ + iterate_and_advance(i, bytes, base, len, off, ({ next = csum_and_copy_to_user(addr + off, base, len); sum = csum_block_add(sum, next, off); next ? 0 : len; @@ -1725,15 +1313,6 @@ int iov_iter_npages(const struct iov_iter *i, int maxpages) return iov_npages(i, maxpages); if (iov_iter_is_bvec(i)) return bvec_npages(i, maxpages); - if (iov_iter_is_pipe(i)) { - int npages; - - if (!sanity(i)) - return 0; - - pipe_npages(i, &npages); - return min(npages, maxpages); - } if (iov_iter_is_xarray(i)) { unsigned offset = (i->xarray_start + i->iov_offset) % PAGE_SIZE; int npages = DIV_ROUND_UP(offset + i->count, PAGE_SIZE); @@ -1746,10 +1325,6 @@ EXPORT_SYMBOL(iov_iter_npages); const void *dup_iter(struct iov_iter *new, struct iov_iter *old, gfp_t flags) { *new = *old; - if (unlikely(iov_iter_is_pipe(new))) { - WARN_ON(1); - return NULL; - } if (iov_iter_is_bvec(new)) return new->bvec = kmemdup(new->bvec, new->nr_segs * sizeof(struct bio_vec), diff --git a/mm/filemap.c b/mm/filemap.c index 0fcb0b80c2e2..603b562d69b1 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2687,8 +2687,7 @@ ssize_t filemap_read(struct kiocb *iocb, struct iov_iter *iter, if (unlikely(iocb->ki_pos >= i_size_read(inode))) break; - error = filemap_get_pages(iocb, iter->count, &fbatch, - iov_iter_is_pipe(iter)); + error = filemap_get_pages(iocb, iter->count, &fbatch, false); if (error < 0) break; -- cgit v1.2.3-70-g09d2 From 9eee8bd81421c5e961cbb1a3c3fa1a06fad545e8 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:18 +0100 Subject: splice: kdoc for filemap_splice_read() and copy_splice_read() Provide kerneldoc comments for filemap_splice_read() and copy_splice_read(). Signed-off-by: David Howells cc: Christian Brauner cc: Christoph Hellwig cc: Jens Axboe cc: Steve French cc: Al Viro cc: linux-mm@kvack.org cc: linux-block@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20230522135018.2742245-32-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/splice.c | 21 +++++++++++++++++++-- mm/filemap.c | 21 ++++++++++++++++++--- 2 files changed, 37 insertions(+), 5 deletions(-) diff --git a/fs/splice.c b/fs/splice.c index 9be4cb3b9879..2420ead610a7 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -299,8 +299,25 @@ void splice_shrink_spd(struct splice_pipe_desc *spd) kfree(spd->partial); } -/* - * Copy data from a file into pages and then splice those into the output pipe. +/** + * copy_splice_read - Copy data from a file and splice the copy into a pipe + * @in: The file to read from + * @ppos: Pointer to the file position to read from + * @pipe: The pipe to splice into + * @len: The amount to splice + * @flags: The SPLICE_F_* flags + * + * This function allocates a bunch of pages sufficient to hold the requested + * amount of data (but limited by the remaining pipe capacity), passes it to + * the file's ->read_iter() to read into and then splices the used pages into + * the pipe. + * + * Return: On success, the number of bytes read will be returned and *@ppos + * will be updated if appropriate; 0 will be returned if there is no more data + * to be read; -EAGAIN will be returned if the pipe had no space, and some + * other negative error code will be returned on error. A short read may occur + * if the pipe has insufficient space, we reach the end of the data or we hit a + * hole. */ ssize_t copy_splice_read(struct file *in, loff_t *ppos, struct pipe_inode_info *pipe, diff --git a/mm/filemap.c b/mm/filemap.c index 603b562d69b1..f87e2ad8cff1 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2871,9 +2871,24 @@ size_t splice_folio_into_pipe(struct pipe_inode_info *pipe, return spliced; } -/* - * Splice folios from the pagecache of a buffered (ie. non-O_DIRECT) file into - * a pipe. +/** + * filemap_splice_read - Splice data from a file's pagecache into a pipe + * @in: The file to read from + * @ppos: Pointer to the file position to read from + * @pipe: The pipe to splice into + * @len: The amount to splice + * @flags: The SPLICE_F_* flags + * + * This function gets folios from a file's pagecache and splices them into the + * pipe. Readahead will be called as necessary to fill more folios. This may + * be used for blockdevs also. + * + * Return: On success, the number of bytes read will be returned and *@ppos + * will be updated if appropriate; 0 will be returned if there is no more data + * to be read; -EAGAIN will be returned if the pipe had no space, and some + * other negative error code will be returned on error. A short read may occur + * if the pipe has insufficient space, we reach the end of the data or we hit a + * hole. */ ssize_t filemap_splice_read(struct file *in, loff_t *ppos, struct pipe_inode_info *pipe, -- cgit v1.2.3-70-g09d2