| Message ID | 20230520000049.2226926-4-dhowells@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | None | expand |
Looks good:
Reviewed-by: Christoph Hellwig <hch@lst.de>
On Sat, May 20, 2023 at 01:00:22AM +0100, David Howells wrote: > Rename direct_splice_read() to copy_splice_read() to better reflect as to > what it does. > > Suggested-by: Christoph Hellwig <hch@lst.de> > Signed-off-by: David Howells <dhowells@redhat.com> > cc: Christoph Hellwig <hch@lst.de> > cc: Steve French <sfrench@samba.org> > cc: Jens Axboe <axboe@kernel.dk> > cc: Al Viro <viro@zeniv.linux.org.uk> > cc: linux-cifs@vger.kernel.org > cc: linux-mm@kvack.org > cc: linux-block@vger.kernel.org > cc: linux-fsdevel@vger.kernel.org > --- For the future it'd be nice if exported functions would always get proper kernel doc, Reviewed-by: Christian Brauner <brauner@kernel.org>
Christian Brauner <brauner@kernel.org> wrote: > For the future it'd be nice if exported functions would always get > proper kernel doc, Good point. It wasn't meant to remain exported originally. I'll add a patch to add that. David
> For the future it'd be nice if exported functions would always get > proper kernel doc, Something like the attached? David --- commit 0362042ba0751fc5457b0548fb9006f9d7dfbeca Author: David Howells <dhowells@redhat.com> Date: Mon May 22 08:34:24 2023 +0100 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 <dhowells@redhat.com> cc: Christian Brauner <brauner@kernel.org> cc: Christoph Hellwig <hch@lst.de> cc: Jens Axboe <axboe@kernel.dk> cc: Steve French <smfrench@gmail.com> cc: Al Viro <viro@zeniv.linux.org.uk> cc: linux-mm@kvack.org cc: linux-block@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: linux-fsdevel@vger.kernel.org diff --git a/fs/splice.c b/fs/splice.c index 9be4cb3b9879..5292a8fa929d 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. + * + * 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..1f235a6430fd 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. + * + * 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,
On Mon, May 22, 2023 at 08:55:14AM +0100, David Howells wrote: > > For the future it'd be nice if exported functions would always get > > proper kernel doc, > > Something like the attached? > > David > --- > commit 0362042ba0751fc5457b0548fb9006f9d7dfbeca > Author: David Howells <dhowells@redhat.com> > Date: Mon May 22 08:34:24 2023 +0100 > > 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 <dhowells@redhat.com> > cc: Christian Brauner <brauner@kernel.org> > cc: Christoph Hellwig <hch@lst.de> > cc: Jens Axboe <axboe@kernel.dk> > cc: Steve French <smfrench@gmail.com> > cc: Al Viro <viro@zeniv.linux.org.uk> > cc: linux-mm@kvack.org > cc: linux-block@vger.kernel.org > cc: linux-cifs@vger.kernel.org > cc: linux-fsdevel@vger.kernel.org > > diff --git a/fs/splice.c b/fs/splice.c > index 9be4cb3b9879..5292a8fa929d 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. > + * > + * 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. > */ I think kdoc expects: * 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. and similar for filemap_splice_read() other than that this looks good! > 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..1f235a6430fd 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. > + * > + * 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, >
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 *,
Rename direct_splice_read() to copy_splice_read() to better reflect as to what it does. Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David Howells <dhowells@redhat.com> cc: Christoph Hellwig <hch@lst.de> cc: Steve French <sfrench@samba.org> cc: Jens Axboe <axboe@kernel.dk> cc: Al Viro <viro@zeniv.linux.org.uk> cc: linux-cifs@vger.kernel.org cc: linux-mm@kvack.org cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org --- 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(-)