From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 367C8C74A52 for ; Thu, 11 Jul 2019 12:28:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1A286216B7 for ; Thu, 11 Jul 2019 12:28:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728576AbfGKM2h (ORCPT ); Thu, 11 Jul 2019 08:28:37 -0400 Received: from mx1.redhat.com ([209.132.183.28]:62761 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725926AbfGKM2h (ORCPT ); Thu, 11 Jul 2019 08:28:37 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 39D9830820C9; Thu, 11 Jul 2019 12:28:36 +0000 (UTC) Received: from max.com (unknown [10.40.205.215]) by smtp.corp.redhat.com (Postfix) with ESMTP id 490E160603; Thu, 11 Jul 2019 12:28:34 +0000 (UTC) From: Andreas Gruenbacher To: Chao Yu Cc: Andreas Gruenbacher , Christoph Hellwig , "Darrick J. Wong" , linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, Gao Xiang , chao@kernel.org Subject: Re: [RFC PATCH] iomap: generalize IOMAP_INLINE to cover tail-packing case Date: Thu, 11 Jul 2019 14:28:31 +0200 Message-Id: <20190711122831.3970-1-agruenba@redhat.com> In-Reply-To: <39944e50-5888-f900-1954-91be2b12ea5b@huawei.com> References: <20190703075502.79782-1-yuchao0@huawei.com> <39944e50-5888-f900-1954-91be2b12ea5b@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.47]); Thu, 11 Jul 2019 12:28:36 +0000 (UTC) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Something along the lines of the attached, broken patch might work in the end. Andreas --- fs/buffer.c | 10 ++++-- fs/iomap.c | 74 +++++++++++++++++++++++++++++-------------- include/linux/iomap.h | 3 ++ 3 files changed, 61 insertions(+), 26 deletions(-) diff --git a/fs/buffer.c b/fs/buffer.c index e450c55f6434..8d8668e377ab 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -1873,8 +1873,8 @@ void page_zero_new_buffers(struct page *page, unsigned from, unsigned to) EXPORT_SYMBOL(page_zero_new_buffers); static void -iomap_to_bh(struct inode *inode, sector_t block, struct buffer_head *bh, - struct iomap *iomap) +iomap_to_bh(struct inode *inode, struct page *page, sector_t block, + struct buffer_head *bh, struct iomap *iomap) { loff_t offset = block << inode->i_blkbits; @@ -1924,6 +1924,10 @@ iomap_to_bh(struct inode *inode, sector_t block, struct buffer_head *bh, inode->i_blkbits; set_buffer_mapped(bh); break; + case IOMAP_INLINE: + __iomap_read_inline_data(inode, page, iomap); + set_buffer_uptodate(bh); + break; } } @@ -1969,7 +1973,7 @@ int __block_write_begin_int(struct page *page, loff_t pos, unsigned len, if (err) break; } else { - iomap_to_bh(inode, block, bh, iomap); + iomap_to_bh(inode, page, block, bh, iomap); } if (buffer_new(bh)) { diff --git a/fs/iomap.c b/fs/iomap.c index 45aa58e837b5..61188e95def2 100644 --- a/fs/iomap.c +++ b/fs/iomap.c @@ -260,24 +260,47 @@ struct iomap_readpage_ctx { struct list_head *pages; }; -static void -iomap_read_inline_data(struct inode *inode, struct page *page, +#define offset_in_block(offset, inode) \ + ((unsigned long)(offset) & (i_blocksize(inode) - 1)) + +static bool +inline_data_within_block(struct inode *inode, struct iomap *iomap, + unsigned int size) +{ + unsigned int off = offset_in_block(iomap->inline_data, inode); + + return size <= i_blocksize(inode) - off; +} + +void +__iomap_read_inline_data(struct inode *inode, struct page *page, struct iomap *iomap) { - size_t size = i_size_read(inode); + size_t size = offset_in_block(i_size_read(inode), inode); + unsigned int poff = offset_in_page(iomap->offset); + unsigned int bsize = i_blocksize(inode); void *addr; if (PageUptodate(page)) return; - BUG_ON(page->index); - BUG_ON(size > PAGE_SIZE - offset_in_page(iomap->inline_data)); + BUG_ON(!inline_data_within_block(inode, iomap, size)); addr = kmap_atomic(page); - memcpy(addr, iomap->inline_data, size); - memset(addr + size, 0, PAGE_SIZE - size); + memcpy(addr + poff, iomap->inline_data, size); + memset(addr + poff + size, 0, bsize - size); kunmap_atomic(addr); - SetPageUptodate(page); +} + +static void +iomap_read_inline_data(struct inode *inode, struct page *page, + struct iomap *iomap) +{ + unsigned int poff = offset_in_page(iomap->offset); + unsigned int bsize = i_blocksize(inode); + + __iomap_read_inline_data(inode, page, iomap); + iomap_set_range_uptodate(page, poff, bsize); } static loff_t @@ -292,11 +315,8 @@ iomap_readpage_actor(struct inode *inode, loff_t pos, loff_t length, void *data, unsigned poff, plen; sector_t sector; - if (iomap->type == IOMAP_INLINE) { - WARN_ON_ONCE(pos); + if (iomap->type == IOMAP_INLINE) iomap_read_inline_data(inode, page, iomap); - return PAGE_SIZE; - } /* zero post-eof blocks as the page may be mapped */ iomap_adjust_read_range(inode, iop, &pos, length, &poff, &plen); @@ -637,6 +657,11 @@ __iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, if (PageUptodate(page)) return 0; + if (iomap->type == IOMAP_INLINE) { + iomap_read_inline_data(inode, page, iomap); + return 0; + } + do { iomap_adjust_read_range(inode, iop, &block_start, block_end - block_start, &poff, &plen); @@ -682,9 +707,7 @@ iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, unsigned flags, goto out_no_page; } - if (iomap->type == IOMAP_INLINE) - iomap_read_inline_data(inode, page, iomap); - else if (iomap->flags & IOMAP_F_BUFFER_HEAD) + if (iomap->flags & IOMAP_F_BUFFER_HEAD) status = __block_write_begin_int(page, pos, len, NULL, iomap); else status = __iomap_write_begin(inode, pos, len, page, iomap); @@ -761,11 +784,11 @@ iomap_write_end_inline(struct inode *inode, struct page *page, { void *addr; - WARN_ON_ONCE(!PageUptodate(page)); - BUG_ON(pos + copied > PAGE_SIZE - offset_in_page(iomap->inline_data)); + BUG_ON(!inline_data_within_block(inode, iomap, pos + copied)); addr = kmap_atomic(page); - memcpy(iomap->inline_data + pos, addr + pos, copied); + memcpy(iomap->inline_data + offset_in_block(pos, inode), + addr + offset_in_page(pos), copied); kunmap_atomic(addr); mark_inode_dirty(inode); @@ -1064,7 +1087,7 @@ iomap_truncate_page(struct inode *inode, loff_t pos, bool *did_zero, const struct iomap_ops *ops) { unsigned int blocksize = i_blocksize(inode); - unsigned int off = pos & (blocksize - 1); + unsigned int off = offset_in_block(pos, inode); /* Block boundary? Nothing to do */ if (!off) @@ -1772,21 +1795,26 @@ iomap_dio_inline_actor(struct inode *inode, loff_t pos, loff_t length, struct iov_iter *iter = dio->submit.iter; size_t copied; - BUG_ON(pos + length > PAGE_SIZE - offset_in_page(iomap->inline_data)); + BUG_ON(!inline_data_within_block(inode, iomap, pos + length)); if (dio->flags & IOMAP_DIO_WRITE) { loff_t size = inode->i_size; if (pos > size) - memset(iomap->inline_data + size, 0, pos - size); - copied = copy_from_iter(iomap->inline_data + pos, length, iter); + memset(iomap->inline_data + + offset_in_block(size, inode), 0, pos - size); + copied = copy_from_iter(iomap->inline_data + + offset_in_block(pos, inode), + length, iter); if (copied) { if (pos + copied > size) i_size_write(inode, pos + copied); mark_inode_dirty(inode); } } else { - copied = copy_to_iter(iomap->inline_data + pos, length, iter); + copied = copy_to_iter(iomap->inline_data + + offset_in_block(pos, inode), + length, iter); } dio->size += copied; return copied; diff --git a/include/linux/iomap.h b/include/linux/iomap.h index 2103b94cb1bf..a8a60dd2fdc0 100644 --- a/include/linux/iomap.h +++ b/include/linux/iomap.h @@ -131,6 +131,9 @@ static inline struct iomap_page *to_iomap_page(struct page *page) return NULL; } +void __iomap_read_inline_data(struct inode *inode, struct page *page, + struct iomap *iomap); + ssize_t iomap_file_buffered_write(struct kiocb *iocb, struct iov_iter *from, const struct iomap_ops *ops); int iomap_readpage(struct page *page, const struct iomap_ops *ops); -- 2.20.1