From 3c435a0fe35c220bec442dffff04a64aacf952b0 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 1 Jun 2023 16:58:56 +0200 Subject: [PATCH] filemap: add a kiocb_write_and_wait helper Factor out a helper that does filemap_write_and_wait_range for the range covered by a read kiocb, or returns -EAGAIN if the kiocb is marked as nowait and there would be pages to write. Link: https://lkml.kernel.org/r/20230601145904.1385409-5-hch@lst.de Signed-off-by: Christoph Hellwig Reviewed-by: Damien Le Moal Reviewed-by: Hannes Reinecke Acked-by: Darrick J. Wong Cc: Al Viro Cc: Andreas Gruenbacher Cc: Anna Schumaker Cc: Chao Yu Cc: Christian Brauner Cc: Ilya Dryomov Cc: Jaegeuk Kim Cc: Jens Axboe Cc: Johannes Thumshirn Cc: Matthew Wilcox Cc: Miklos Szeredi Cc: Miklos Szeredi Cc: Theodore Ts'o Cc: Trond Myklebust Cc: Xiubo Li Signed-off-by: Andrew Morton --- block/fops.c | 18 +++--------------- include/linux/pagemap.h | 2 ++ mm/filemap.c | 30 ++++++++++++++++++------------ 3 files changed, 23 insertions(+), 27 deletions(-) diff --git a/block/fops.c b/block/fops.c index 58d0aebc7313..575171049c5d 100644 --- a/block/fops.c +++ b/block/fops.c @@ -576,21 +576,9 @@ static ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to) goto reexpand; /* skip atime */ if (iocb->ki_flags & IOCB_DIRECT) { - struct address_space *mapping = iocb->ki_filp->f_mapping; - - if (iocb->ki_flags & IOCB_NOWAIT) { - if (filemap_range_needs_writeback(mapping, pos, - pos + count - 1)) { - ret = -EAGAIN; - goto reexpand; - } - } else { - ret = filemap_write_and_wait_range(mapping, pos, - pos + count - 1); - if (ret < 0) - goto reexpand; - } - + ret = kiocb_write_and_wait(iocb, count); + if (ret < 0) + goto reexpand; file_accessed(iocb->ki_filp); ret = blkdev_direct_IO(iocb, to); diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index c1ae5ebc375f..b6a12ca108b7 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -30,6 +30,7 @@ static inline void invalidate_remote_inode(struct inode *inode) int invalidate_inode_pages2(struct address_space *mapping); int invalidate_inode_pages2_range(struct address_space *mapping, pgoff_t start, pgoff_t end); + int write_inode_now(struct inode *, int sync); int filemap_fdatawrite(struct address_space *); int filemap_flush(struct address_space *); @@ -54,6 +55,7 @@ int filemap_check_errors(struct address_space *mapping); void __filemap_set_wb_err(struct address_space *mapping, int err); int filemap_fdatawrite_wbc(struct address_space *mapping, struct writeback_control *wbc); +int kiocb_write_and_wait(struct kiocb *iocb, size_t count); static inline int filemap_write_and_wait(struct address_space *mapping) { diff --git a/mm/filemap.c b/mm/filemap.c index 3a80a69fa9fa..5566e10ca1a7 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2735,6 +2735,21 @@ put_folios: } EXPORT_SYMBOL_GPL(filemap_read); +int kiocb_write_and_wait(struct kiocb *iocb, size_t count) +{ + struct address_space *mapping = iocb->ki_filp->f_mapping; + loff_t pos = iocb->ki_pos; + loff_t end = pos + count - 1; + + if (iocb->ki_flags & IOCB_NOWAIT) { + if (filemap_range_needs_writeback(mapping, pos, end)) + return -EAGAIN; + return 0; + } + + return filemap_write_and_wait_range(mapping, pos, end); +} + /** * generic_file_read_iter - generic filesystem read routine * @iocb: kernel I/O control block @@ -2770,18 +2785,9 @@ generic_file_read_iter(struct kiocb *iocb, struct iov_iter *iter) struct address_space *mapping = file->f_mapping; struct inode *inode = mapping->host; - if (iocb->ki_flags & IOCB_NOWAIT) { - if (filemap_range_needs_writeback(mapping, iocb->ki_pos, - iocb->ki_pos + count - 1)) - return -EAGAIN; - } else { - retval = filemap_write_and_wait_range(mapping, - iocb->ki_pos, - iocb->ki_pos + count - 1); - if (retval < 0) - return retval; - } - + retval = kiocb_write_and_wait(iocb, count); + if (retval < 0) + return retval; file_accessed(file); retval = mapping->a_ops->direct_IO(iocb, iter); -- 2.11.0