From: Christoph Hellwig hch@lst.de
commit e003f74afbd2feadbb9ffbf9135e2d2fb5d320a5 upstream.
Factor out a helper that calls filemap_write_and_wait_range and invalidate_inode_pages2_range for the range covered by a write kiocb or returns -EAGAIN if the kiocb is marked as nowait and there would be pages to write or invalidate.
Link: https://lkml.kernel.org/r/20230601145904.1385409-6-hch@lst.de Signed-off-by: Christoph Hellwig hch@lst.de Reviewed-by: Damien Le Moal dlemoal@kernel.org Reviewed-by: Hannes Reinecke hare@suse.de Acked-by: Darrick J. Wong djwong@kernel.org Cc: Al Viro viro@zeniv.linux.org.uk Cc: Andreas Gruenbacher agruenba@redhat.com Cc: Anna Schumaker anna@kernel.org Cc: Chao Yu chao@kernel.org Cc: Christian Brauner brauner@kernel.org Cc: Ilya Dryomov idryomov@gmail.com Cc: Jaegeuk Kim jaegeuk@kernel.org Cc: Jens Axboe axboe@kernel.dk Cc: Johannes Thumshirn johannes.thumshirn@wdc.com Cc: Matthew Wilcox willy@infradead.org Cc: Miklos Szeredi miklos@szeredi.hu Cc: Miklos Szeredi mszeredi@redhat.com Cc: Theodore Ts'o tytso@mit.edu Cc: Trond Myklebust trond.myklebust@hammerspace.com Cc: Xiubo Li xiubli@redhat.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Mahmoud Adam mngyadam@amazon.de --- include/linux/pagemap.h | 1 + mm/filemap.c | 48 ++++++++++++++++++++++++----------------- 2 files changed, 29 insertions(+), 20 deletions(-)
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 1be5a1fa6a3a84..bb462e5a91e28d 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 kiocb_invalidate_pages(struct kiocb *iocb, size_t count); int write_inode_now(struct inode *, int sync); int filemap_fdatawrite(struct address_space *); int filemap_flush(struct address_space *); diff --git a/mm/filemap.c b/mm/filemap.c index 2ae6c6146d848a..0923b8df285886 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2839,6 +2839,33 @@ ssize_t filemap_read(struct kiocb *iocb, struct iov_iter *iter, } EXPORT_SYMBOL_GPL(filemap_read);
+int kiocb_invalidate_pages(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; + int ret; + + if (iocb->ki_flags & IOCB_NOWAIT) { + /* we could block if there are any pages in the range */ + if (filemap_range_has_page(mapping, pos, end)) + return -EAGAIN; + } else { + ret = filemap_write_and_wait_range(mapping, pos, end); + if (ret) + return ret; + } + + /* + * After a write we want buffered reads to be sure to go to disk to get + * the new data. We invalidate clean cached page from the region we're + * about to write. We do this *before* the write so that we can return + * without clobbering -EIOCBQUEUED from ->direct_IO(). + */ + return invalidate_inode_pages2_range(mapping, pos >> PAGE_SHIFT, + end >> PAGE_SHIFT); +} + /** * generic_file_read_iter - generic filesystem read routine * @iocb: kernel I/O control block @@ -3737,30 +3764,11 @@ generic_file_direct_write(struct kiocb *iocb, struct iov_iter *from) write_len = iov_iter_count(from); end = (pos + write_len - 1) >> PAGE_SHIFT;
- if (iocb->ki_flags & IOCB_NOWAIT) { - /* If there are pages to writeback, return */ - if (filemap_range_has_page(file->f_mapping, pos, - pos + write_len - 1)) - return -EAGAIN; - } else { - written = filemap_write_and_wait_range(mapping, pos, - pos + write_len - 1); - if (written) - goto out; - } - - /* - * After a write we want buffered reads to be sure to go to disk to get - * the new data. We invalidate clean cached page from the region we're - * about to write. We do this *before* the write so that we can return - * without clobbering -EIOCBQUEUED from ->direct_IO(). - */ - written = invalidate_inode_pages2_range(mapping, - pos >> PAGE_SHIFT, end); /* * If a page can not be invalidated, return 0 to fall back * to buffered write. */ + written = kiocb_invalidate_pages(iocb, write_len); if (written) { if (written == -EBUSY) return 0;