From patchwork Fri Jun 7 14:58:58 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Pankaj Raghav (Samsung)" X-Patchwork-Id: 13690323 Received: from mout-p-202.mailbox.org (mout-p-202.mailbox.org [80.241.56.172]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A299C19DF44; Fri, 7 Jun 2024 14:59:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=80.241.56.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717772384; cv=none; b=NsPGIlAsHGyJtY0hp0uHYHj5qX3Rh+zXolKwui+h59tJ3qbmGVnkCnMAa4rLJXfQUQJ6b2EG89LyHGf50KNGQN7smRaa9uLMMApbdxdmGRDwZ3W/WAnz2rKR57VZIkrR2u0mEEH9O47UQhOQGutid2TAeRPg4Ie7dquM0Qmt7T4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717772384; c=relaxed/simple; bh=ov2TaelLlm3wME5xgPGGulvGW/SCE21E2+YFkubwphg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=fy6vCVQd46Cvlz0ocVT8Nj7pyzqjVYIsDFOS0SIUp+JUkDh9fGwpuGjckZPPw9ZsVEOYBN35VSQv0o0fEBcvwHJzHVx2ki3yU3fJHE5SXnXj/Bl81xASN+CnfiIKo3Yx1ZKJQ9WnS3EWuv2uLEJGWoSOndLdX6Ta1wOEoSn9AKU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=pankajraghav.com; spf=pass smtp.mailfrom=pankajraghav.com; dkim=pass (2048-bit key) header.d=pankajraghav.com header.i=@pankajraghav.com header.b=G8rJmHPP; arc=none smtp.client-ip=80.241.56.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=pankajraghav.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pankajraghav.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=pankajraghav.com header.i=@pankajraghav.com header.b="G8rJmHPP" Received: from smtp102.mailbox.org (smtp102.mailbox.org [IPv6:2001:67c:2050:b231:465::102]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mout-p-202.mailbox.org (Postfix) with ESMTPS id 4Vwkr96mtFz9sQg; Fri, 7 Jun 2024 16:59:37 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pankajraghav.com; s=MBO0001; t=1717772377; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8sLXh3ItwEq5TYZ7rJHrfyrYcE/YpAXA+GtXY9esiOQ=; b=G8rJmHPPcxHDWg9xX/dktQ9HwiydrWEABafRT0DQVy8yun8SAsiK2HjYovvsfD5tVewnLU e7vCv0u+F3IDEkMs18wVCelFF2ytkEpFlyJ2UHfSCGpjQgl9Zm3XPmXkOE5Stwz+ivsiu5 s+6IBi9WHp6kYkf1WfMmcP0yU+306PvjCpL45362UtPH2MixOdqebdY0grac6KOrRpEREn sDu5S4JegDjd8Q8z7xfpbF4Xr8wwvQb7z40XHmLfgquiHYp3yZLjhvhi6mEZEtWImeg/ph Do6WmwQ31Zv2BMk8zutT+kBCCfXWK0y9kDt1dRtkeBNviEt4xKtPZ6E304xGqQ== From: "Pankaj Raghav (Samsung)" To: david@fromorbit.com, djwong@kernel.org, chandan.babu@oracle.com, brauner@kernel.org, akpm@linux-foundation.org, willy@infradead.org Cc: mcgrof@kernel.org, linux-mm@kvack.org, hare@suse.de, linux-kernel@vger.kernel.org, yang@os.amperecomputing.com, Zi Yan , linux-xfs@vger.kernel.org, p.raghav@samsung.com, linux-fsdevel@vger.kernel.org, kernel@pankajraghav.com, hch@lst.de, gost.dev@samsung.com, cl@os.amperecomputing.com, john.g.garry@oracle.com Subject: [PATCH v7 07/11] iomap: fix iomap_dio_zero() for fs bs > system page size Date: Fri, 7 Jun 2024 14:58:58 +0000 Message-ID: <20240607145902.1137853-8-kernel@pankajraghav.com> In-Reply-To: <20240607145902.1137853-1-kernel@pankajraghav.com> References: <20240607145902.1137853-1-kernel@pankajraghav.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Rspamd-Queue-Id: 4Vwkr96mtFz9sQg From: Pankaj Raghav iomap_dio_zero() will pad a fs block with zeroes if the direct IO size < fs block size. iomap_dio_zero() has an implicit assumption that fs block size < page_size. This is true for most filesystems at the moment. If the block size > page size, this will send the contents of the page next to zero page(as len > PAGE_SIZE) to the underlying block device, causing FS corruption. iomap is a generic infrastructure and it should not make any assumptions about the fs block size and the page size of the system. Signed-off-by: Pankaj Raghav Reviewed-by: Hannes Reinecke --- fs/internal.h | 5 +++++ fs/iomap/buffered-io.c | 6 ++++++ fs/iomap/direct-io.c | 26 ++++++++++++++++++++++++-- 3 files changed, 35 insertions(+), 2 deletions(-) diff --git a/fs/internal.h b/fs/internal.h index 84f371193f74..30217f0ff4c6 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -35,6 +35,11 @@ static inline void bdev_cache_init(void) int __block_write_begin_int(struct folio *folio, loff_t pos, unsigned len, get_block_t *get_block, const struct iomap *iomap); +/* + * iomap/direct-io.c + */ +int iomap_dio_init(void); + /* * char_dev.c */ diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 49938419fcc7..9f791db473e4 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -1990,6 +1990,12 @@ EXPORT_SYMBOL_GPL(iomap_writepages); static int __init iomap_init(void) { + int ret; + + ret = iomap_dio_init(); + if (ret) + return ret; + return bioset_init(&iomap_ioend_bioset, 4 * (PAGE_SIZE / SECTOR_SIZE), offsetof(struct iomap_ioend, io_bio), BIOSET_NEED_BVECS); diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c index f3b43d223a46..b95600b254a3 100644 --- a/fs/iomap/direct-io.c +++ b/fs/iomap/direct-io.c @@ -27,6 +27,13 @@ #define IOMAP_DIO_WRITE (1U << 30) #define IOMAP_DIO_DIRTY (1U << 31) +/* + * Used for sub block zeroing in iomap_dio_zero() + */ +#define ZERO_FSB_SIZE (65536) +#define ZERO_FSB_ORDER (get_order(ZERO_FSB_SIZE)) +static struct page *zero_fs_block; + struct iomap_dio { struct kiocb *iocb; const struct iomap_dio_ops *dops; @@ -52,6 +59,16 @@ struct iomap_dio { }; }; +int iomap_dio_init(void) +{ + zero_fs_block = alloc_pages(GFP_KERNEL | __GFP_ZERO, ZERO_FSB_ORDER); + + if (!zero_fs_block) + return -ENOMEM; + + return 0; +} + static struct bio *iomap_dio_alloc_bio(const struct iomap_iter *iter, struct iomap_dio *dio, unsigned short nr_vecs, blk_opf_t opf) { @@ -236,17 +253,22 @@ static void iomap_dio_zero(const struct iomap_iter *iter, struct iomap_dio *dio, loff_t pos, unsigned len) { struct inode *inode = file_inode(dio->iocb->ki_filp); - struct page *page = ZERO_PAGE(0); struct bio *bio; + /* + * Max block size supported is 64k + */ + WARN_ON_ONCE(len > ZERO_FSB_SIZE); + bio = iomap_dio_alloc_bio(iter, dio, 1, REQ_OP_WRITE | REQ_SYNC | REQ_IDLE); fscrypt_set_bio_crypt_ctx(bio, inode, pos >> inode->i_blkbits, GFP_KERNEL); + bio->bi_iter.bi_sector = iomap_sector(&iter->iomap, pos); bio->bi_private = dio; bio->bi_end_io = iomap_dio_bio_end_io; - __bio_add_page(bio, page, len, 0); + __bio_add_page(bio, zero_fs_block, len, 0); iomap_dio_submit_bio(iter, dio, bio, pos); }