From patchwork Sun Apr 10 16:08:58 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shiyang Ruan X-Patchwork-Id: 12808192 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 41D6BC433FE for ; Sun, 10 Apr 2022 16:09:18 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id CA45C6B0073; Sun, 10 Apr 2022 12:09:17 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C521B8D0001; Sun, 10 Apr 2022 12:09:17 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id AA42E6B0075; Sun, 10 Apr 2022 12:09:17 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.hostedemail.com [64.99.140.27]) by kanga.kvack.org (Postfix) with ESMTP id 8D1186B0073 for ; Sun, 10 Apr 2022 12:09:17 -0400 (EDT) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 695A223A3A for ; Sun, 10 Apr 2022 16:09:17 +0000 (UTC) X-FDA: 79341453954.01.670BB44 Received: from heian.cn.fujitsu.com (mail.cn.fujitsu.com [183.91.158.132]) by imf01.hostedemail.com (Postfix) with ESMTP id BC46540005 for ; Sun, 10 Apr 2022 16:09:15 +0000 (UTC) IronPort-Data: A9a23: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 IronPort-HdrOrdr: A9a23:fUoj8qz/6FbRIfuTxbALKrPwyL1zdoMgy1knxilNoRw8SKKlfqeV7ZImPH7P+U8ssR4b+exoVJPtfZqYz+8R3WBzB8bEYOCFghrKEGgK1+KLqFeMJ8S9zJ846U4KSclD4bPLYmSS9fyKgjVQDexQveWvweS5g/vE1XdxQUVPY6Fk1Q1wDQGWCSRNNXJ7LKt8BJyB/dBGujblXXwWa/6wDn4DU/OGiMbMkPvdEGQ7Li9i+A+Tlimp9bK/NxCZ2y0VWzRJzaxn0UWtqX2A2pme X-IronPort-AV: E=Sophos;i="5.88,333,1635177600"; d="scan'208";a="123453818" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 11 Apr 2022 00:09:08 +0800 Received: from G08CNEXMBPEKD06.g08.fujitsu.local (unknown [10.167.33.206]) by cn.fujitsu.com (Postfix) with ESMTP id 8EEE34D17163; Mon, 11 Apr 2022 00:09:06 +0800 (CST) Received: from G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.85) by G08CNEXMBPEKD06.g08.fujitsu.local (10.167.33.206) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Mon, 11 Apr 2022 00:09:05 +0800 Received: from irides.mr.mr (10.167.225.141) by G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.209) with Microsoft SMTP Server id 15.0.1497.23 via Frontend Transport; Mon, 11 Apr 2022 00:09:05 +0800 From: Shiyang Ruan To: , , , , CC: , , , , Subject: [PATCH v12 1/7] dax: Introduce holder for dax_device Date: Mon, 11 Apr 2022 00:08:58 +0800 Message-ID: <20220410160904.3758789-2-ruansy.fnst@fujitsu.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220410160904.3758789-1-ruansy.fnst@fujitsu.com> References: <20220410160904.3758789-1-ruansy.fnst@fujitsu.com> MIME-Version: 1.0 X-yoursite-MailScanner-ID: 8EEE34D17163.A40B1 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: ruansy.fnst@fujitsu.com X-Stat-Signature: 5nzjh4jwkcgku599sj4cxai5royzcasq Authentication-Results: imf01.hostedemail.com; dkim=none; spf=none (imf01.hostedemail.com: domain of ruansy.fnst@fujitsu.com has no SPF policy when checking 183.91.158.132) smtp.mailfrom=ruansy.fnst@fujitsu.com; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=fujitsu.com (policy=none) X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: BC46540005 X-HE-Tag: 1649606955-362189 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: To easily track filesystem from a pmem device, we introduce a holder for dax_device structure, and also its operation. This holder is used to remember who is using this dax_device: - When it is the backend of a filesystem, the holder will be the instance of this filesystem. - When this pmem device is one of the targets in a mapped device, the holder will be this mapped device. In this case, the mapped device has its own dax_device and it will follow the first rule. So that we can finally track to the filesystem we needed. The holder and holder_ops will be set when filesystem is being mounted, or an target device is being activated. Signed-off-by: Shiyang Ruan Reviewed-by: Christoph Hellwig Reviewed-by: Dan Williams --- drivers/dax/super.c | 66 ++++++++++++++++++++++++++++++++++++++++++++- drivers/md/dm.c | 2 +- fs/erofs/super.c | 10 ++++--- fs/ext2/super.c | 7 ++--- fs/ext4/super.c | 9 ++++--- fs/xfs/xfs_buf.c | 5 ++-- include/linux/dax.h | 33 +++++++++++++++++------ 7 files changed, 109 insertions(+), 23 deletions(-) diff --git a/drivers/dax/super.c b/drivers/dax/super.c index 0211e6f7b47a..619a05615497 100644 --- a/drivers/dax/super.c +++ b/drivers/dax/super.c @@ -22,6 +22,8 @@ * @private: dax driver private data * @flags: state and boolean properties * @ops: operations for this device + * @holder_data: holder of a dax_device: could be filesystem or mapped device + * @holder_ops: operations for the inner holder */ struct dax_device { struct inode inode; @@ -29,6 +31,8 @@ struct dax_device { void *private; unsigned long flags; const struct dax_operations *ops; + void *holder_data; + const struct dax_holder_operations *holder_ops; }; static dev_t dax_devt; @@ -71,8 +75,11 @@ EXPORT_SYMBOL_GPL(dax_remove_host); * fs_dax_get_by_bdev() - temporary lookup mechanism for filesystem-dax * @bdev: block device to find a dax_device for * @start_off: returns the byte offset into the dax_device that @bdev starts + * @holder: filesystem or mapped device inside the dax_device + * @ops: operations for the inner holder */ -struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev, u64 *start_off) +struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev, u64 *start_off, + void *holder, const struct dax_holder_operations *ops) { struct dax_device *dax_dev; u64 part_size; @@ -92,11 +99,25 @@ struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev, u64 *start_off) dax_dev = xa_load(&dax_hosts, (unsigned long)bdev->bd_disk); if (!dax_dev || !dax_alive(dax_dev) || !igrab(&dax_dev->inode)) dax_dev = NULL; + else if (holder) { + if (!cmpxchg(&dax_dev->holder_data, NULL, holder)) + dax_dev->holder_ops = ops; + else + dax_dev = NULL; + } dax_read_unlock(id); return dax_dev; } EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev); + +void fs_put_dax(struct dax_device *dax_dev, void *holder) +{ + if (holder && cmpxchg(&dax_dev->holder_data, holder, NULL) == holder) + dax_dev->holder_ops = NULL; + put_dax(dax_dev); +} +EXPORT_SYMBOL_GPL(fs_put_dax); #endif /* CONFIG_BLOCK && CONFIG_FS_DAX */ enum dax_device_flags { @@ -194,6 +215,29 @@ int dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff, } EXPORT_SYMBOL_GPL(dax_zero_page_range); +int dax_holder_notify_failure(struct dax_device *dax_dev, u64 off, + u64 len, int mf_flags) +{ + int rc, id; + + id = dax_read_lock(); + if (!dax_alive(dax_dev)) { + rc = -ENXIO; + goto out; + } + + if (!dax_dev->holder_ops) { + rc = -EOPNOTSUPP; + goto out; + } + + rc = dax_dev->holder_ops->notify_failure(dax_dev, off, len, mf_flags); +out: + dax_read_unlock(id); + return rc; +} +EXPORT_SYMBOL_GPL(dax_holder_notify_failure); + #ifdef CONFIG_ARCH_HAS_PMEM_API void arch_wb_cache_pmem(void *addr, size_t size); void dax_flush(struct dax_device *dax_dev, void *addr, size_t size) @@ -267,8 +311,15 @@ void kill_dax(struct dax_device *dax_dev) if (!dax_dev) return; + if (dax_dev->holder_data != NULL) + dax_holder_notify_failure(dax_dev, 0, U64_MAX, 0); + clear_bit(DAXDEV_ALIVE, &dax_dev->flags); synchronize_srcu(&dax_srcu); + + /* clear holder data */ + dax_dev->holder_ops = NULL; + dax_dev->holder_data = NULL; } EXPORT_SYMBOL_GPL(kill_dax); @@ -410,6 +461,19 @@ void put_dax(struct dax_device *dax_dev) } EXPORT_SYMBOL_GPL(put_dax); +/** + * dax_holder() - obtain the holder of a dax device + * @dax_dev: a dax_device instance + + * Return: the holder's data which represents the holder if registered, + * otherwize NULL. + */ +void *dax_holder(struct dax_device *dax_dev) +{ + return dax_dev->holder_data; +} +EXPORT_SYMBOL_GPL(dax_holder); + /** * inode_dax: convert a public inode into its dax_dev * @inode: An inode with i_cdev pointing to a dax_dev diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 8200a7498baf..d165ab828b04 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -729,7 +729,7 @@ static int open_table_device(struct table_device *td, dev_t dev, } td->dm_dev.bdev = bdev; - td->dm_dev.dax_dev = fs_dax_get_by_bdev(bdev, &part_off); + td->dm_dev.dax_dev = fs_dax_get_by_bdev(bdev, &part_off, NULL, NULL); return 0; } diff --git a/fs/erofs/super.c b/fs/erofs/super.c index 0c4b41130c2f..d0eab646ef94 100644 --- a/fs/erofs/super.c +++ b/fs/erofs/super.c @@ -267,7 +267,8 @@ static int erofs_init_devices(struct super_block *sb, break; } dif->bdev = bdev; - dif->dax_dev = fs_dax_get_by_bdev(bdev, &dif->dax_part_off); + dif->dax_dev = fs_dax_get_by_bdev(bdev, &dif->dax_part_off, + NULL, NULL); dif->blocks = le32_to_cpu(dis->blocks); dif->mapped_blkaddr = le32_to_cpu(dis->mapped_blkaddr); sbi->total_blocks += dif->blocks; @@ -597,7 +598,8 @@ static int erofs_fc_fill_super(struct super_block *sb, struct fs_context *fc) sb->s_fs_info = sbi; sbi->opt = ctx->opt; - sbi->dax_dev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->dax_part_off); + sbi->dax_dev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->dax_part_off, + NULL, NULL); sbi->devs = ctx->devs; ctx->devs = NULL; @@ -687,7 +689,7 @@ static int erofs_release_device_info(int id, void *ptr, void *data) { struct erofs_device_info *dif = ptr; - fs_put_dax(dif->dax_dev); + fs_put_dax(dif->dax_dev, NULL); if (dif->bdev) blkdev_put(dif->bdev, FMODE_READ | FMODE_EXCL); kfree(dif->path); @@ -756,7 +758,7 @@ static void erofs_kill_sb(struct super_block *sb) return; erofs_free_dev_context(sbi->devs); - fs_put_dax(sbi->dax_dev); + fs_put_dax(sbi->dax_dev, NULL); kfree(sbi); sb->s_fs_info = NULL; } diff --git a/fs/ext2/super.c b/fs/ext2/super.c index f6a19f6d9f6d..4638946251b9 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -171,7 +171,7 @@ static void ext2_put_super (struct super_block * sb) brelse (sbi->s_sbh); sb->s_fs_info = NULL; kfree(sbi->s_blockgroup_lock); - fs_put_dax(sbi->s_daxdev); + fs_put_dax(sbi->s_daxdev, NULL); kfree(sbi); } @@ -835,7 +835,8 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent) } sb->s_fs_info = sbi; sbi->s_sb_block = sb_block; - sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off); + sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off, + NULL, NULL); spin_lock_init(&sbi->s_lock); ret = -EINVAL; @@ -1204,7 +1205,7 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent) failed_mount: brelse(bh); failed_sbi: - fs_put_dax(sbi->s_daxdev); + fs_put_dax(sbi->s_daxdev, NULL); sb->s_fs_info = NULL; kfree(sbi->s_blockgroup_lock); kfree(sbi); diff --git a/fs/ext4/super.c b/fs/ext4/super.c index f5f4f2606ab2..59d5b2e8f838 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1300,7 +1300,7 @@ static void ext4_put_super(struct super_block *sb) if (sbi->s_chksum_driver) crypto_free_shash(sbi->s_chksum_driver); kfree(sbi->s_blockgroup_lock); - fs_put_dax(sbi->s_daxdev); + fs_put_dax(sbi->s_daxdev, NULL); fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy); #if IS_ENABLED(CONFIG_UNICODE) utf8_unload(sb->s_encoding); @@ -4351,7 +4351,7 @@ static void ext4_free_sbi(struct ext4_sb_info *sbi) return; kfree(sbi->s_blockgroup_lock); - fs_put_dax(sbi->s_daxdev); + fs_put_dax(sbi->s_daxdev, NULL); kfree(sbi); } @@ -4363,7 +4363,8 @@ static struct ext4_sb_info *ext4_alloc_sbi(struct super_block *sb) if (!sbi) return NULL; - sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off); + sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off, + NULL, NULL); sbi->s_blockgroup_lock = kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL); @@ -4375,7 +4376,7 @@ static struct ext4_sb_info *ext4_alloc_sbi(struct super_block *sb) sbi->s_sb = sb; return sbi; err_out: - fs_put_dax(sbi->s_daxdev); + fs_put_dax(sbi->s_daxdev, NULL); kfree(sbi); return NULL; } diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index e1afb9e503e1..f9ca08398d32 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -1911,7 +1911,7 @@ xfs_free_buftarg( list_lru_destroy(&btp->bt_lru); blkdev_issue_flush(btp->bt_bdev); - fs_put_dax(btp->bt_daxdev); + fs_put_dax(btp->bt_daxdev, NULL); kmem_free(btp); } @@ -1964,7 +1964,8 @@ xfs_alloc_buftarg( btp->bt_mount = mp; btp->bt_dev = bdev->bd_dev; btp->bt_bdev = bdev; - btp->bt_daxdev = fs_dax_get_by_bdev(bdev, &btp->bt_dax_part_off); + btp->bt_daxdev = fs_dax_get_by_bdev(bdev, &btp->bt_dax_part_off, NULL, + NULL); /* * Buffer IO error rate limiting. Limit it to no more than 10 messages diff --git a/include/linux/dax.h b/include/linux/dax.h index 9fc5f99a0ae2..9c426a207ba8 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -32,8 +32,21 @@ struct dax_operations { int (*zero_page_range)(struct dax_device *, pgoff_t, size_t); }; +struct dax_holder_operations { + /* + * notify_failure - notify memory failure into inner holder device + * @dax_dev: the dax device which contains the holder + * @offset: offset on this dax device where memory failure occurs + * @len: length of this memory failure event + * @flags: action flags for memory failure handler + */ + int (*notify_failure)(struct dax_device *dax_dev, u64 offset, + u64 len, int mf_flags); +}; + #if IS_ENABLED(CONFIG_DAX) struct dax_device *alloc_dax(void *private, const struct dax_operations *ops); +void *dax_holder(struct dax_device *dax_dev); void put_dax(struct dax_device *dax_dev); void kill_dax(struct dax_device *dax_dev); void dax_write_cache(struct dax_device *dax_dev, bool wc); @@ -53,6 +66,10 @@ static inline bool daxdev_mapping_supported(struct vm_area_struct *vma, return dax_synchronous(dax_dev); } #else +static inline void *dax_holder(struct dax_device *dax_dev) +{ + return NULL; +} static inline struct dax_device *alloc_dax(void *private, const struct dax_operations *ops) { @@ -96,12 +113,9 @@ struct writeback_control; #if defined(CONFIG_BLOCK) && defined(CONFIG_FS_DAX) int dax_add_host(struct dax_device *dax_dev, struct gendisk *disk); void dax_remove_host(struct gendisk *disk); -struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev, - u64 *start_off); -static inline void fs_put_dax(struct dax_device *dax_dev) -{ - put_dax(dax_dev); -} +struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev, u64 *start_off, + void *holder, const struct dax_holder_operations *ops); +void fs_put_dax(struct dax_device *dax_dev, void *holder); #else static inline int dax_add_host(struct dax_device *dax_dev, struct gendisk *disk) { @@ -111,11 +125,12 @@ static inline void dax_remove_host(struct gendisk *disk) { } static inline struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev, - u64 *start_off) + u64 *start_off, void *holder, + const struct dax_holder_operations *ops) { return NULL; } -static inline void fs_put_dax(struct dax_device *dax_dev) +static inline void fs_put_dax(struct dax_device *dax_dev, void *holder) { } #endif /* CONFIG_BLOCK && CONFIG_FS_DAX */ @@ -185,6 +200,8 @@ size_t dax_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr, size_t bytes, struct iov_iter *i); int dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff, size_t nr_pages); +int dax_holder_notify_failure(struct dax_device *dax_dev, u64 off, u64 len, + int mf_flags); void dax_flush(struct dax_device *dax_dev, void *addr, size_t size); ssize_t dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter, From patchwork Sun Apr 10 16:08:59 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shiyang Ruan X-Patchwork-Id: 12808191 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id A2E49C433F5 for ; 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d="scan'208";a="123453819" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 11 Apr 2022 00:09:08 +0800 Received: from G08CNEXMBPEKD04.g08.fujitsu.local (unknown [10.167.33.201]) by cn.fujitsu.com (Postfix) with ESMTP id 3F9104D17165; Mon, 11 Apr 2022 00:09:07 +0800 (CST) Received: from G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.85) by G08CNEXMBPEKD04.g08.fujitsu.local (10.167.33.201) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Mon, 11 Apr 2022 00:09:10 +0800 Received: from irides.mr.mr (10.167.225.141) by G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.209) with Microsoft SMTP Server id 15.0.1497.23 via Frontend Transport; Mon, 11 Apr 2022 00:09:05 +0800 From: Shiyang Ruan To: , , , , CC: , , , , , Christoph Hellwig Subject: [PATCH v12 2/7] mm: factor helpers for memory_failure_dev_pagemap Date: Mon, 11 Apr 2022 00:08:59 +0800 Message-ID: <20220410160904.3758789-3-ruansy.fnst@fujitsu.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220410160904.3758789-1-ruansy.fnst@fujitsu.com> References: <20220410160904.3758789-1-ruansy.fnst@fujitsu.com> MIME-Version: 1.0 X-yoursite-MailScanner-ID: 3F9104D17165.A02EF X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: ruansy.fnst@fujitsu.com X-Stat-Signature: 4oh17efiq7dby846poqahx4rb4sq7zqg Authentication-Results: imf29.hostedemail.com; dkim=none; spf=none (imf29.hostedemail.com: domain of ruansy.fnst@fujitsu.com has no SPF policy when checking 183.91.158.132) smtp.mailfrom=ruansy.fnst@fujitsu.com; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=fujitsu.com (policy=none) X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 684B3120004 X-HE-Tag: 1649606953-47910 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: memory_failure_dev_pagemap code is a bit complex before introduce RMAP feature for fsdax. So it is needed to factor some helper functions to simplify these code. Signed-off-by: Shiyang Ruan Reviewed-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Reviewed-by: Dan Williams Reported-by: kernel test robot Reported-by: kernel test robot --- mm/memory-failure.c | 157 ++++++++++++++++++++++++-------------------- 1 file changed, 87 insertions(+), 70 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index ef402b490663..f1cdd39f01f7 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1499,6 +1499,90 @@ static int try_to_split_thp_page(struct page *page, const char *msg) return 0; } +static void unmap_and_kill(struct list_head *to_kill, unsigned long pfn, + struct address_space *mapping, pgoff_t index, int flags) +{ + struct to_kill *tk; + unsigned long size = 0; + + list_for_each_entry(tk, to_kill, nd) + if (tk->size_shift) + size = max(size, 1UL << tk->size_shift); + + if (size) { + /* + * Unmap the largest mapping to avoid breaking up device-dax + * mappings which are constant size. The actual size of the + * mapping being torn down is communicated in siginfo, see + * kill_proc() + */ + loff_t start = (index << PAGE_SHIFT) & ~(size - 1); + + unmap_mapping_range(mapping, start, size, 0); + } + + kill_procs(to_kill, flags & MF_MUST_KILL, false, pfn, flags); +} + +static int mf_generic_kill_procs(unsigned long long pfn, int flags, + struct dev_pagemap *pgmap) +{ + struct page *page = pfn_to_page(pfn); + LIST_HEAD(to_kill); + dax_entry_t cookie; + int rc = 0; + + /* + * Pages instantiated by device-dax (not filesystem-dax) + * may be compound pages. + */ + page = compound_head(page); + + /* + * Prevent the inode from being freed while we are interrogating + * the address_space, typically this would be handled by + * lock_page(), but dax pages do not use the page lock. This + * also prevents changes to the mapping of this pfn until + * poison signaling is complete. + */ + cookie = dax_lock_page(page); + if (!cookie) + return -EBUSY; + + if (hwpoison_filter(page)) { + rc = -EOPNOTSUPP; + goto unlock; + } + + if (pgmap->type == MEMORY_DEVICE_PRIVATE) { + /* + * TODO: Handle HMM pages which may need coordination + * with device-side memory. + */ + return -EBUSY; + } + + /* + * Use this flag as an indication that the dax page has been + * remapped UC to prevent speculative consumption of poison. + */ + SetPageHWPoison(page); + + /* + * Unlike System-RAM there is no possibility to swap in a + * different physical page at a given virtual address, so all + * userspace consumption of ZONE_DEVICE memory necessitates + * SIGBUS (i.e. MF_MUST_KILL) + */ + flags |= MF_ACTION_REQUIRED | MF_MUST_KILL; + collect_procs(page, &to_kill, true); + + unmap_and_kill(&to_kill, pfn, page->mapping, page->index, flags); +unlock: + dax_unlock_page(page, cookie); + return 0; +} + /* * Called from hugetlb code with hugetlb_lock held. * If a hugepage is successfully grabbed (so it's determined to handle @@ -1663,12 +1747,8 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, struct dev_pagemap *pgmap) { struct page *page = pfn_to_page(pfn); - unsigned long size = 0; - struct to_kill *tk; LIST_HEAD(tokill); - int rc = -EBUSY; - loff_t start; - dax_entry_t cookie; + int rc = -ENXIO; if (flags & MF_COUNT_INCREASED) /* @@ -1677,73 +1757,10 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, put_page(page); /* device metadata space is not recoverable */ - if (!pgmap_pfn_valid(pgmap, pfn)) { - rc = -ENXIO; - goto out; - } - - /* - * Pages instantiated by device-dax (not filesystem-dax) - * may be compound pages. - */ - page = compound_head(page); - - /* - * Prevent the inode from being freed while we are interrogating - * the address_space, typically this would be handled by - * lock_page(), but dax pages do not use the page lock. This - * also prevents changes to the mapping of this pfn until - * poison signaling is complete. - */ - cookie = dax_lock_page(page); - if (!cookie) + if (!pgmap_pfn_valid(pgmap, pfn)) goto out; - if (hwpoison_filter(page)) { - rc = -EOPNOTSUPP; - goto unlock; - } - - if (pgmap->type == MEMORY_DEVICE_PRIVATE) { - /* - * TODO: Handle HMM pages which may need coordination - * with device-side memory. - */ - goto unlock; - } - - /* - * Use this flag as an indication that the dax page has been - * remapped UC to prevent speculative consumption of poison. - */ - SetPageHWPoison(page); - - /* - * Unlike System-RAM there is no possibility to swap in a - * different physical page at a given virtual address, so all - * userspace consumption of ZONE_DEVICE memory necessitates - * SIGBUS (i.e. MF_MUST_KILL) - */ - flags |= MF_ACTION_REQUIRED | MF_MUST_KILL; - collect_procs(page, &tokill, true); - - list_for_each_entry(tk, &tokill, nd) - if (tk->size_shift) - size = max(size, 1UL << tk->size_shift); - if (size) { - /* - * Unmap the largest mapping to avoid breaking up - * device-dax mappings which are constant size. The - * actual size of the mapping being torn down is - * communicated in siginfo, see kill_proc() - */ - start = (page->index << PAGE_SHIFT) & ~(size - 1); - unmap_mapping_range(page->mapping, start, size, 0); - } - kill_procs(&tokill, true, false, pfn, flags); - rc = 0; -unlock: - dax_unlock_page(page, cookie); + rc = mf_generic_kill_procs(pfn, flags, pgmap); out: /* drop pgmap ref acquired in caller */ put_dev_pagemap(pgmap); From patchwork Sun Apr 10 16:09:00 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shiyang Ruan X-Patchwork-Id: 12808197 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 420BAC4167B for ; Sun, 10 Apr 2022 16:09:27 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 17EB18D0009; Sun, 10 Apr 2022 12:09:21 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0BCE08D0008; Sun, 10 Apr 2022 12:09:21 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E74F08D0007; Sun, 10 Apr 2022 12:09:20 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.a.hostedemail.com [64.99.140.24]) by kanga.kvack.org (Postfix) with ESMTP id D424F8D0001 for ; Sun, 10 Apr 2022 12:09:20 -0400 (EDT) Received: from smtpin19.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id AB33C60BE8 for ; Sun, 10 Apr 2022 16:09:20 +0000 (UTC) X-FDA: 79341454080.19.6B4124A Received: from heian.cn.fujitsu.com (mail.cn.fujitsu.com [183.91.158.132]) by imf28.hostedemail.com (Postfix) with ESMTP id 9B115C0009 for ; Sun, 10 Apr 2022 16:09:19 +0000 (UTC) IronPort-Data: A9a23:dJVMt6sgi77g3nfW6un2/wR/J+fnVClfMUV32f8akzHdYEJGY0x3mmZNDT3TOvaKZ2HwLdwjao2zpxxTvMTQzNAyQVY9qyBgHilAwSbnLY7Hdx+vZUt+DSFioHpPtpxYMp+ZRCwNZie0SiyFb/6x/RGQ6YnSHuCmULScY3goLeNZYHxJZSxLyrdRbrFA0YDR7zOl4bsekuWHULOX82cc3lE8t8pvnChSUMHa41v0iLCRicdj5zcyn1FNZH4WyDrYw3HQGuG4FcbiLwrPIS3Qw4/Xw/stIovNfrfTeUtMTKPQPBSVlzxdXK3Kbhpq/3R0i/hkcqFHLxo/ZzahxridzP1XqJW2UhZvMKvXhMwTThtZDzpje6ZB/dcrJFDm65fPkhaWKSaEL/JGSRte0Zcj0up+H2BC3fICLzUKdBqCm6S9x7fTYulnhuwiKsfxNY8Ss30myivWZd4qSJaFQePV5Ntc3T41nehPG+rTY4wSbj8HRBjCfBpJNX8UBYg4kePugWPwGxVcqVSIte8y5kDQ0gV60/7qKtW9UtqUScRQm26cp3na5CL9AxcHJJqTxCTt2nKnhsfLhj+9VI96PL+x8PMsi12O7msJARYSWB2wpvzRokq/Xc9PbkIP9icwoKwa6kOmVJ/+Uge+rXrCuQQTM/JUEusn+ESOx7DS7gKxGGcJVHhCZcYguctwQiYlvneNntX0FXl/vqa9V32Q7PGXoCm0NCxTKnUNDRLo5yNtD8LL+dl110yQCI04VvPdszE8IhmoqxjikcT0r+l7YRY36piG IronPort-HdrOrdr: A9a23:PzkseaEOnCFFHz4/pLqE1MeALOsnbusQ8zAXPiFKOHhom6mj+vxG88506faKslwssR0b+OxoW5PwJE80l6QFgrX5VI3KNGbbUQCTXeNfBOXZowHIKmnX8+5x8eNaebFiNduYNzNHpPe/zA6mM9tI+rW6zJw= X-IronPort-AV: E=Sophos;i="5.88,333,1635177600"; d="scan'208";a="123453825" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 11 Apr 2022 00:09:14 +0800 Received: from G08CNEXMBPEKD04.g08.fujitsu.local (unknown [10.167.33.201]) by cn.fujitsu.com (Postfix) with ESMTP id DB49A4D16FF4; Mon, 11 Apr 2022 00:09:07 +0800 (CST) Received: from G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.85) by G08CNEXMBPEKD04.g08.fujitsu.local (10.167.33.201) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Mon, 11 Apr 2022 00:09:11 +0800 Received: from irides.mr.mr (10.167.225.141) by G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.209) with Microsoft SMTP Server id 15.0.1497.23 via Frontend Transport; Mon, 11 Apr 2022 00:09:06 +0800 From: Shiyang Ruan To: , , , , CC: , , , , , Christoph Hellwig Subject: [PATCH v12 3/7] pagemap,pmem: Introduce ->memory_failure() Date: Mon, 11 Apr 2022 00:09:00 +0800 Message-ID: <20220410160904.3758789-4-ruansy.fnst@fujitsu.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220410160904.3758789-1-ruansy.fnst@fujitsu.com> References: <20220410160904.3758789-1-ruansy.fnst@fujitsu.com> MIME-Version: 1.0 X-yoursite-MailScanner-ID: DB49A4D16FF4.A5EAD X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: ruansy.fnst@fujitsu.com X-Stat-Signature: 3phori37t7d6mi5gpz67g5c3g4dbf3s6 Authentication-Results: imf28.hostedemail.com; dkim=none; spf=none (imf28.hostedemail.com: domain of ruansy.fnst@fujitsu.com has no SPF policy when checking 183.91.158.132) smtp.mailfrom=ruansy.fnst@fujitsu.com; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=fujitsu.com (policy=none) X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 9B115C0009 X-HE-Tag: 1649606959-285510 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: When memory-failure occurs, we call this function which is implemented by each kind of devices. For the fsdax case, pmem device driver implements it. Pmem device driver will find out the filesystem in which the corrupted page located in. With dax_holder notify support, we are able to notify the memory failure from pmem driver to upper layers. If there is something not support in the notify routine, memory_failure will fall back to the generic hanlder. Signed-off-by: Shiyang Ruan Reviewed-by: Christoph Hellwig Reviewed-by: Dan Williams --- drivers/nvdimm/pmem.c | 17 +++++++++++++++++ include/linux/memremap.h | 12 ++++++++++++ mm/memory-failure.c | 14 ++++++++++++++ 3 files changed, 43 insertions(+) diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 58d95242a836..bd502957cfdf 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -366,6 +366,21 @@ static void pmem_release_disk(void *__pmem) blk_cleanup_disk(pmem->disk); } +static int pmem_pagemap_memory_failure(struct dev_pagemap *pgmap, + unsigned long pfn, unsigned long nr_pages, int mf_flags) +{ + struct pmem_device *pmem = + container_of(pgmap, struct pmem_device, pgmap); + u64 offset = PFN_PHYS(pfn) - pmem->phys_addr - pmem->data_offset; + u64 len = nr_pages << PAGE_SHIFT; + + return dax_holder_notify_failure(pmem->dax_dev, offset, len, mf_flags); +} + +static const struct dev_pagemap_ops fsdax_pagemap_ops = { + .memory_failure = pmem_pagemap_memory_failure, +}; + static int pmem_attach_disk(struct device *dev, struct nd_namespace_common *ndns) { @@ -427,6 +442,7 @@ static int pmem_attach_disk(struct device *dev, pmem->pfn_flags = PFN_DEV; if (is_nd_pfn(dev)) { pmem->pgmap.type = MEMORY_DEVICE_FS_DAX; + pmem->pgmap.ops = &fsdax_pagemap_ops; addr = devm_memremap_pages(dev, &pmem->pgmap); pfn_sb = nd_pfn->pfn_sb; pmem->data_offset = le64_to_cpu(pfn_sb->dataoff); @@ -440,6 +456,7 @@ static int pmem_attach_disk(struct device *dev, pmem->pgmap.range.end = res->end; pmem->pgmap.nr_range = 1; pmem->pgmap.type = MEMORY_DEVICE_FS_DAX; + pmem->pgmap.ops = &fsdax_pagemap_ops; addr = devm_memremap_pages(dev, &pmem->pgmap); pmem->pfn_flags |= PFN_MAP; bb_range = pmem->pgmap.range; diff --git a/include/linux/memremap.h b/include/linux/memremap.h index ad6062d736cd..bcfb6bf4ce5a 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -79,6 +79,18 @@ struct dev_pagemap_ops { * the page back to a CPU accessible page. */ vm_fault_t (*migrate_to_ram)(struct vm_fault *vmf); + + /* + * Handle the memory failure happens on a range of pfns. Notify the + * processes who are using these pfns, and try to recover the data on + * them if necessary. The mf_flags is finally passed to the recover + * function through the whole notify routine. + * + * When this is not implemented, or it returns -EOPNOTSUPP, the caller + * will fall back to a common handler called mf_generic_kill_procs(). + */ + int (*memory_failure)(struct dev_pagemap *pgmap, unsigned long pfn, + unsigned long nr_pages, int mf_flags); }; #define PGMAP_ALTMAP_VALID (1 << 0) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index f1cdd39f01f7..c8c898669c75 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1760,6 +1760,20 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, if (!pgmap_pfn_valid(pgmap, pfn)) goto out; + /* + * Call driver's implementation to handle the memory failure, otherwise + * fall back to generic handler. + */ + if (pgmap->ops->memory_failure) { + rc = pgmap->ops->memory_failure(pgmap, pfn, 1, flags); + /* + * Fall back to generic handler too if operation is not + * supported inside the driver/device/filesystem. + */ + if (rc != -EOPNOTSUPP) + goto out; + } + rc = mf_generic_kill_procs(pfn, flags, pgmap); out: /* drop pgmap ref acquired in caller */ From patchwork Sun Apr 10 16:09:01 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shiyang Ruan X-Patchwork-Id: 12808198 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id C9CFDC43219 for ; Sun, 10 Apr 2022 16:09:28 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 63A828D0007; Sun, 10 Apr 2022 12:09:21 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 59F838D0001; Sun, 10 Apr 2022 12:09:21 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 17C788D0007; Sun, 10 Apr 2022 12:09:21 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0139.hostedemail.com [216.40.44.139]) by kanga.kvack.org (Postfix) with ESMTP id F100F8D0001 for ; 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d="scan'208";a="123453823" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 11 Apr 2022 00:09:14 +0800 Received: from G08CNEXMBPEKD06.g08.fujitsu.local (unknown [10.167.33.206]) by cn.fujitsu.com (Postfix) with ESMTP id C00324D17163; Mon, 11 Apr 2022 00:09:08 +0800 (CST) Received: from G08CNEXJMPEKD02.g08.fujitsu.local (10.167.33.202) by G08CNEXMBPEKD06.g08.fujitsu.local (10.167.33.206) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Mon, 11 Apr 2022 00:09:08 +0800 Received: from G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.85) by G08CNEXJMPEKD02.g08.fujitsu.local (10.167.33.202) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Mon, 11 Apr 2022 00:09:11 +0800 Received: from irides.mr.mr (10.167.225.141) by G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.209) with Microsoft SMTP Server id 15.0.1497.23 via Frontend Transport; Mon, 11 Apr 2022 00:09:07 +0800 From: Shiyang Ruan To: , , , , CC: , , , , , Christoph Hellwig Subject: [PATCH v12 4/7] fsdax: Introduce dax_lock_mapping_entry() Date: Mon, 11 Apr 2022 00:09:01 +0800 Message-ID: <20220410160904.3758789-5-ruansy.fnst@fujitsu.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220410160904.3758789-1-ruansy.fnst@fujitsu.com> References: <20220410160904.3758789-1-ruansy.fnst@fujitsu.com> MIME-Version: 1.0 X-yoursite-MailScanner-ID: C00324D17163.AF597 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: ruansy.fnst@fujitsu.com X-Stat-Signature: af15ou3djrnr9gyb791k9st3f99qz6dw Authentication-Results: imf01.hostedemail.com; dkim=none; spf=none (imf01.hostedemail.com: domain of ruansy.fnst@fujitsu.com has no SPF policy when checking 183.91.158.132) smtp.mailfrom=ruansy.fnst@fujitsu.com; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=fujitsu.com (policy=none) X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 8B0BB40005 X-HE-Tag: 1649606959-978961 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: The current dax_lock_page() locks dax entry by obtaining mapping and index in page. To support 1-to-N RMAP in NVDIMM, we need a new function to lock a specific dax entry corresponding to this file's mapping,index. And output the page corresponding to the specific dax entry for caller use. Signed-off-by: Shiyang Ruan Reviewed-by: Christoph Hellwig --- fs/dax.c | 63 +++++++++++++++++++++++++++++++++++++++++++++ include/linux/dax.h | 15 +++++++++++ 2 files changed, 78 insertions(+) diff --git a/fs/dax.c b/fs/dax.c index 1ac12e877f4f..57efd3f73655 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -455,6 +455,69 @@ void dax_unlock_page(struct page *page, dax_entry_t cookie) dax_unlock_entry(&xas, (void *)cookie); } +/* + * dax_lock_mapping_entry - Lock the DAX entry corresponding to a mapping + * @mapping: the file's mapping whose entry we want to lock + * @index: the offset within this file + * @page: output the dax page corresponding to this dax entry + * + * Return: A cookie to pass to dax_unlock_mapping_entry() or 0 if the entry + * could not be locked. + */ +dax_entry_t dax_lock_mapping_entry(struct address_space *mapping, pgoff_t index, + struct page **page) +{ + XA_STATE(xas, NULL, 0); + void *entry; + + rcu_read_lock(); + for (;;) { + entry = NULL; + if (!dax_mapping(mapping)) + break; + + xas.xa = &mapping->i_pages; + xas_lock_irq(&xas); + xas_set(&xas, index); + entry = xas_load(&xas); + if (dax_is_locked(entry)) { + rcu_read_unlock(); + wait_entry_unlocked(&xas, entry); + rcu_read_lock(); + continue; + } + if (!entry || + dax_is_zero_entry(entry) || dax_is_empty_entry(entry)) { + /* + * Because we are looking for entry from file's mapping + * and index, so the entry may not be inserted for now, + * or even a zero/empty entry. We don't think this is + * an error case. So, return a special value and do + * not output @page. + */ + entry = (void *)~0UL; + } else { + *page = pfn_to_page(dax_to_pfn(entry)); + dax_lock_entry(&xas, entry); + } + xas_unlock_irq(&xas); + break; + } + rcu_read_unlock(); + return (dax_entry_t)entry; +} + +void dax_unlock_mapping_entry(struct address_space *mapping, pgoff_t index, + dax_entry_t cookie) +{ + XA_STATE(xas, &mapping->i_pages, index); + + if (cookie == ~0UL) + return; + + dax_unlock_entry(&xas, (void *)cookie); +} + /* * Find page cache entry at given index. If it is a DAX entry, return it * with the entry locked. If the page cache doesn't contain an entry at diff --git a/include/linux/dax.h b/include/linux/dax.h index 9c426a207ba8..c152f315d1c9 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -143,6 +143,10 @@ struct page *dax_layout_busy_page(struct address_space *mapping); struct page *dax_layout_busy_page_range(struct address_space *mapping, loff_t start, loff_t end); dax_entry_t dax_lock_page(struct page *page); void dax_unlock_page(struct page *page, dax_entry_t cookie); +dax_entry_t dax_lock_mapping_entry(struct address_space *mapping, + unsigned long index, struct page **page); +void dax_unlock_mapping_entry(struct address_space *mapping, + unsigned long index, dax_entry_t cookie); #else static inline struct page *dax_layout_busy_page(struct address_space *mapping) { @@ -170,6 +174,17 @@ static inline dax_entry_t dax_lock_page(struct page *page) static inline void dax_unlock_page(struct page *page, dax_entry_t cookie) { } + +static inline dax_entry_t dax_lock_mapping_entry(struct address_space *mapping, + unsigned long index, struct page **page) +{ + return 0; +} + +static inline void dax_unlock_mapping_entry(struct address_space *mapping, + unsigned long index, dax_entry_t cookie) +{ +} #endif int dax_zero_range(struct inode *inode, loff_t pos, loff_t len, bool *did_zero, From patchwork Sun Apr 10 16:09:02 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shiyang Ruan X-Patchwork-Id: 12808196 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8F2AAC433F5 for ; Sun, 10 Apr 2022 16:09:25 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 0BAA98D0006; Sun, 10 Apr 2022 12:09:20 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id F10608D0001; Sun, 10 Apr 2022 12:09:19 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CEDB78D0007; 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d="scan'208";a="123453824" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 11 Apr 2022 00:09:14 +0800 Received: from G08CNEXMBPEKD05.g08.fujitsu.local (unknown [10.167.33.204]) by cn.fujitsu.com (Postfix) with ESMTP id 31C3C4D17165; Mon, 11 Apr 2022 00:09:09 +0800 (CST) Received: from G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.85) by G08CNEXMBPEKD05.g08.fujitsu.local (10.167.33.204) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Mon, 11 Apr 2022 00:09:10 +0800 Received: from irides.mr.mr (10.167.225.141) by G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.209) with Microsoft SMTP Server id 15.0.1497.23 via Frontend Transport; Mon, 11 Apr 2022 00:09:07 +0800 From: Shiyang Ruan To: , , , , CC: , , , , , Christoph Hellwig Subject: [PATCH v12 5/7] mm: Introduce mf_dax_kill_procs() for fsdax case Date: Mon, 11 Apr 2022 00:09:02 +0800 Message-ID: <20220410160904.3758789-6-ruansy.fnst@fujitsu.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220410160904.3758789-1-ruansy.fnst@fujitsu.com> References: <20220410160904.3758789-1-ruansy.fnst@fujitsu.com> MIME-Version: 1.0 X-yoursite-MailScanner-ID: 31C3C4D17165.AFA2A X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: ruansy.fnst@fujitsu.com X-Stat-Signature: gynii8fi6jahtk79ayf8umytkprbij6k Authentication-Results: imf29.hostedemail.com; dkim=none; spf=none (imf29.hostedemail.com: domain of ruansy.fnst@fujitsu.com has no SPF policy when checking 183.91.158.132) smtp.mailfrom=ruansy.fnst@fujitsu.com; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=fujitsu.com (policy=none) X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 4CD3F120003 X-HE-Tag: 1649606957-494761 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: This new function is a variant of mf_generic_kill_procs that accepts a file, offset pair instead o a struct to support multiple files sharing a DAX mapping. It is intended to be called by the file systems as part of the memory_failure handler after the file system performed a reverse mapping from the storage address to the file and file offset. Signed-off-by: Shiyang Ruan Reviewed-by: Dan Williams Reviewed-by: Christoph Hellwig --- include/linux/mm.h | 2 + mm/memory-failure.c | 96 ++++++++++++++++++++++++++++++++++++++++----- 2 files changed, 88 insertions(+), 10 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index e0ad13486035..742604feef28 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3226,6 +3226,8 @@ enum mf_flags { MF_SOFT_OFFLINE = 1 << 3, MF_UNPOISON = 1 << 4, }; +int mf_dax_kill_procs(struct address_space *mapping, pgoff_t index, + unsigned long count, int mf_flags); extern int memory_failure(unsigned long pfn, int flags); extern void memory_failure_queue(unsigned long pfn, int flags); extern void memory_failure_queue_kick(int cpu); diff --git a/mm/memory-failure.c b/mm/memory-failure.c index c8c898669c75..0664115c570b 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -295,10 +295,9 @@ void shake_page(struct page *p) } EXPORT_SYMBOL_GPL(shake_page); -static unsigned long dev_pagemap_mapping_shift(struct page *page, - struct vm_area_struct *vma) +static unsigned long dev_pagemap_mapping_shift(struct vm_area_struct *vma, + unsigned long address) { - unsigned long address = vma_address(page, vma); unsigned long ret = 0; pgd_t *pgd; p4d_t *p4d; @@ -338,10 +337,14 @@ static unsigned long dev_pagemap_mapping_shift(struct page *page, /* * Schedule a process for later kill. * Uses GFP_ATOMIC allocations to avoid potential recursions in the VM. + * + * Notice: @fsdax_pgoff is used only when @p is a fsdax page. + * In other cases, such as anonymous and file-backend page, the address to be + * killed can be caculated by @p itself. */ static void add_to_kill(struct task_struct *tsk, struct page *p, - struct vm_area_struct *vma, - struct list_head *to_kill) + pgoff_t fsdax_pgoff, struct vm_area_struct *vma, + struct list_head *to_kill) { struct to_kill *tk; @@ -352,9 +355,15 @@ static void add_to_kill(struct task_struct *tsk, struct page *p, } tk->addr = page_address_in_vma(p, vma); - if (is_zone_device_page(p)) - tk->size_shift = dev_pagemap_mapping_shift(p, vma); - else + if (is_zone_device_page(p)) { + /* + * Since page->mapping is not used for fsdax, we need + * calculate the address based on the vma. + */ + if (p->pgmap->type == MEMORY_DEVICE_FS_DAX) + tk->addr = vma_pgoff_address(fsdax_pgoff, 1, vma); + tk->size_shift = dev_pagemap_mapping_shift(vma, tk->addr); + } else tk->size_shift = page_shift(compound_head(p)); /* @@ -503,7 +512,7 @@ static void collect_procs_anon(struct page *page, struct list_head *to_kill, if (!page_mapped_in_vma(page, vma)) continue; if (vma->vm_mm == t->mm) - add_to_kill(t, page, vma, to_kill); + add_to_kill(t, page, 0, vma, to_kill); } } read_unlock(&tasklist_lock); @@ -539,13 +548,41 @@ static void collect_procs_file(struct page *page, struct list_head *to_kill, * to be informed of all such data corruptions. */ if (vma->vm_mm == t->mm) - add_to_kill(t, page, vma, to_kill); + add_to_kill(t, page, 0, vma, to_kill); } } read_unlock(&tasklist_lock); i_mmap_unlock_read(mapping); } +#if IS_ENABLED(CONFIG_FS_DAX) +/* + * Collect processes when the error hit a fsdax page. + */ +static void collect_procs_fsdax(struct page *page, + struct address_space *mapping, pgoff_t pgoff, + struct list_head *to_kill) +{ + struct vm_area_struct *vma; + struct task_struct *tsk; + + i_mmap_lock_read(mapping); + read_lock(&tasklist_lock); + for_each_process(tsk) { + struct task_struct *t = task_early_kill(tsk, true); + + if (!t) + continue; + vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) { + if (vma->vm_mm == t->mm) + add_to_kill(t, page, pgoff, vma, to_kill); + } + } + read_unlock(&tasklist_lock); + i_mmap_unlock_read(mapping); +} +#endif /* CONFIG_FS_DAX */ + /* * Collect the processes who have the corrupted page mapped to kill. */ @@ -1583,6 +1620,45 @@ static int mf_generic_kill_procs(unsigned long long pfn, int flags, return 0; } +#ifdef CONFIG_FS_DAX +/** + * mf_dax_kill_procs - Collect and kill processes who are using this file range + * @mapping: the file in use + * @index: start pgoff of the range within the file + * @count: length of the range, in unit of PAGE_SIZE + * @mf_flags: memory failure flags + */ +int mf_dax_kill_procs(struct address_space *mapping, pgoff_t index, + unsigned long count, int mf_flags) +{ + LIST_HEAD(to_kill); + dax_entry_t cookie; + struct page *page; + size_t end = index + count; + + mf_flags |= MF_ACTION_REQUIRED | MF_MUST_KILL; + + for (; index < end; index++) { + page = NULL; + cookie = dax_lock_mapping_entry(mapping, index, &page); + if (!cookie) + return -EBUSY; + if (!page) + goto unlock; + + SetPageHWPoison(page); + + collect_procs_fsdax(page, mapping, index, &to_kill); + unmap_and_kill(&to_kill, page_to_pfn(page), mapping, + index, mf_flags); +unlock: + dax_unlock_mapping_entry(mapping, index, cookie); + } + return 0; +} +EXPORT_SYMBOL_GPL(mf_dax_kill_procs); +#endif /* CONFIG_FS_DAX */ + /* * Called from hugetlb code with hugetlb_lock held. * If a hugepage is successfully grabbed (so it's determined to handle From patchwork Sun Apr 10 16:09:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shiyang Ruan X-Patchwork-Id: 12808194 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 965EDC433FE for ; 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d="scan'208";a="123453822" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 11 Apr 2022 00:09:14 +0800 Received: from G08CNEXMBPEKD06.g08.fujitsu.local (unknown [10.167.33.206]) by cn.fujitsu.com (Postfix) with ESMTP id CE03A4D17167; Mon, 11 Apr 2022 00:09:09 +0800 (CST) Received: from G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.85) by G08CNEXMBPEKD06.g08.fujitsu.local (10.167.33.206) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Mon, 11 Apr 2022 00:09:08 +0800 Received: from irides.mr.mr (10.167.225.141) by G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.209) with Microsoft SMTP Server id 15.0.1497.23 via Frontend Transport; Mon, 11 Apr 2022 00:09:08 +0800 From: Shiyang Ruan To: , , , , CC: , , , , Subject: [PATCH v12 6/7] xfs: Implement ->notify_failure() for XFS Date: Mon, 11 Apr 2022 00:09:03 +0800 Message-ID: <20220410160904.3758789-7-ruansy.fnst@fujitsu.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220410160904.3758789-1-ruansy.fnst@fujitsu.com> References: <20220410160904.3758789-1-ruansy.fnst@fujitsu.com> MIME-Version: 1.0 X-yoursite-MailScanner-ID: CE03A4D17167.A3E70 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: ruansy.fnst@fujitsu.com X-Stat-Signature: x9j9s4itsmjox7ag3z7u15rqiqypixia Authentication-Results: imf01.hostedemail.com; dkim=none; spf=none (imf01.hostedemail.com: domain of ruansy.fnst@fujitsu.com has no SPF policy when checking 183.91.158.132) smtp.mailfrom=ruansy.fnst@fujitsu.com; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=fujitsu.com (policy=none) X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: C39C240003 X-HE-Tag: 1649606957-724815 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Introduce xfs_notify_failure.c to handle failure related works, such as implement ->notify_failure(), register/unregister dax holder in xfs, and so on. If the rmap feature of XFS enabled, we can query it to find files and metadata which are associated with the corrupt data. For now all we do is kill processes with that file mapped into their address spaces, but future patches could actually do something about corrupt metadata. After that, the memory failure needs to notify the processes who are using those files. Signed-off-by: Shiyang Ruan Reported-by: kernel test robot Reported-by: kernel test robot Reviewed-by: Christoph Hellwig Reported-by: kernel test robot --- fs/xfs/Makefile | 5 + fs/xfs/xfs_buf.c | 7 +- fs/xfs/xfs_fsops.c | 3 + fs/xfs/xfs_mount.h | 1 + fs/xfs/xfs_notify_failure.c | 219 ++++++++++++++++++++++++++++++++++++ fs/xfs/xfs_super.h | 1 + 6 files changed, 233 insertions(+), 3 deletions(-) create mode 100644 fs/xfs/xfs_notify_failure.c diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile index 04611a1068b4..09f5560e29f2 100644 --- a/fs/xfs/Makefile +++ b/fs/xfs/Makefile @@ -128,6 +128,11 @@ xfs-$(CONFIG_SYSCTL) += xfs_sysctl.o xfs-$(CONFIG_COMPAT) += xfs_ioctl32.o xfs-$(CONFIG_EXPORTFS_BLOCK_OPS) += xfs_pnfs.o +# notify failure +ifeq ($(CONFIG_MEMORY_FAILURE),y) +xfs-$(CONFIG_FS_DAX) += xfs_notify_failure.o +endif + # online scrub/repair ifeq ($(CONFIG_XFS_ONLINE_SCRUB),y) diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index f9ca08398d32..9064b8dfbc66 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -5,6 +5,7 @@ */ #include "xfs.h" #include +#include #include "xfs_shared.h" #include "xfs_format.h" @@ -1911,7 +1912,7 @@ xfs_free_buftarg( list_lru_destroy(&btp->bt_lru); blkdev_issue_flush(btp->bt_bdev); - fs_put_dax(btp->bt_daxdev, NULL); + fs_put_dax(btp->bt_daxdev, btp->bt_mount); kmem_free(btp); } @@ -1964,8 +1965,8 @@ xfs_alloc_buftarg( btp->bt_mount = mp; btp->bt_dev = bdev->bd_dev; btp->bt_bdev = bdev; - btp->bt_daxdev = fs_dax_get_by_bdev(bdev, &btp->bt_dax_part_off, NULL, - NULL); + btp->bt_daxdev = fs_dax_get_by_bdev(bdev, &btp->bt_dax_part_off, mp, + &xfs_dax_holder_operations); /* * Buffer IO error rate limiting. Limit it to no more than 10 messages diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c index 68f74549fa22..56530900bb86 100644 --- a/fs/xfs/xfs_fsops.c +++ b/fs/xfs/xfs_fsops.c @@ -536,6 +536,9 @@ xfs_do_force_shutdown( } else if (flags & SHUTDOWN_CORRUPT_INCORE) { tag = XFS_PTAG_SHUTDOWN_CORRUPT; why = "Corruption of in-memory data"; + } else if (flags & SHUTDOWN_CORRUPT_ONDISK) { + tag = XFS_PTAG_SHUTDOWN_CORRUPT; + why = "Corruption of on-disk metadata"; } else { tag = XFS_PTAG_SHUTDOWN_IOERROR; why = "Metadata I/O Error"; diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h index f6dc19de8322..9237cc159542 100644 --- a/fs/xfs/xfs_mount.h +++ b/fs/xfs/xfs_mount.h @@ -435,6 +435,7 @@ void xfs_do_force_shutdown(struct xfs_mount *mp, int flags, char *fname, #define SHUTDOWN_LOG_IO_ERROR 0x0002 /* write attempt to the log failed */ #define SHUTDOWN_FORCE_UMOUNT 0x0004 /* shutdown from a forced unmount */ #define SHUTDOWN_CORRUPT_INCORE 0x0008 /* corrupt in-memory data structures */ +#define SHUTDOWN_CORRUPT_ONDISK 0x0010 /* corrupt metadata on device */ #define XFS_SHUTDOWN_STRINGS \ { SHUTDOWN_META_IO_ERROR, "metadata_io" }, \ diff --git a/fs/xfs/xfs_notify_failure.c b/fs/xfs/xfs_notify_failure.c new file mode 100644 index 000000000000..aac44f54feb4 --- /dev/null +++ b/fs/xfs/xfs_notify_failure.c @@ -0,0 +1,219 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2022 Fujitsu. All Rights Reserved. + */ + +#include "xfs.h" +#include "xfs_shared.h" +#include "xfs_format.h" +#include "xfs_log_format.h" +#include "xfs_trans_resv.h" +#include "xfs_mount.h" +#include "xfs_alloc.h" +#include "xfs_bit.h" +#include "xfs_btree.h" +#include "xfs_inode.h" +#include "xfs_icache.h" +#include "xfs_rmap.h" +#include "xfs_rmap_btree.h" +#include "xfs_rtalloc.h" +#include "xfs_trans.h" + +#include +#include + +struct failure_info { + xfs_agblock_t startblock; + xfs_extlen_t blockcount; + int mf_flags; +}; + +static pgoff_t +xfs_failure_pgoff( + struct xfs_mount *mp, + const struct xfs_rmap_irec *rec, + const struct failure_info *notify) +{ + uint64_t pos = rec->rm_offset; + + if (notify->startblock > rec->rm_startblock) + pos += XFS_FSB_TO_B(mp, + notify->startblock - rec->rm_startblock); + return pos >> PAGE_SHIFT; +} + +static unsigned long +xfs_failure_pgcnt( + struct xfs_mount *mp, + const struct xfs_rmap_irec *rec, + const struct failure_info *notify) +{ + xfs_agblock_t end_rec; + xfs_agblock_t end_notify; + xfs_agblock_t start_cross; + xfs_agblock_t end_cross; + + start_cross = max(rec->rm_startblock, notify->startblock); + + end_rec = rec->rm_startblock + rec->rm_blockcount; + end_notify = notify->startblock + notify->blockcount; + end_cross = min(end_rec, end_notify); + + return XFS_FSB_TO_B(mp, end_cross - start_cross) >> PAGE_SHIFT; +} + +static int +xfs_dax_failure_fn( + struct xfs_btree_cur *cur, + const struct xfs_rmap_irec *rec, + void *data) +{ + struct xfs_mount *mp = cur->bc_mp; + struct xfs_inode *ip; + struct failure_info *notify = data; + int error = 0; + + if (XFS_RMAP_NON_INODE_OWNER(rec->rm_owner) || + (rec->rm_flags & (XFS_RMAP_ATTR_FORK | XFS_RMAP_BMBT_BLOCK))) { + xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_ONDISK); + return -EFSCORRUPTED; + } + + /* Get files that incore, filter out others that are not in use. */ + error = xfs_iget(mp, cur->bc_tp, rec->rm_owner, XFS_IGET_INCORE, + 0, &ip); + /* Continue the rmap query if the inode isn't incore */ + if (error == -ENODATA) + return 0; + if (error) + return error; + + error = mf_dax_kill_procs(VFS_I(ip)->i_mapping, + xfs_failure_pgoff(mp, rec, notify), + xfs_failure_pgcnt(mp, rec, notify), + notify->mf_flags); + xfs_irele(ip); + return error; +} + +static int +xfs_dax_notify_ddev_failure( + struct xfs_mount *mp, + xfs_daddr_t daddr, + xfs_daddr_t bblen, + int mf_flags) +{ + struct xfs_trans *tp = NULL; + struct xfs_btree_cur *cur = NULL; + struct xfs_buf *agf_bp = NULL; + int error = 0; + xfs_fsblock_t fsbno = XFS_DADDR_TO_FSB(mp, daddr); + xfs_agnumber_t agno = XFS_FSB_TO_AGNO(mp, fsbno); + xfs_fsblock_t end_fsbno = XFS_DADDR_TO_FSB(mp, daddr + bblen); + xfs_agnumber_t end_agno = XFS_FSB_TO_AGNO(mp, end_fsbno); + + error = xfs_trans_alloc_empty(mp, &tp); + if (error) + return error; + + for (; agno <= end_agno; agno++) { + struct xfs_rmap_irec ri_low = { }; + struct xfs_rmap_irec ri_high; + struct failure_info notify; + struct xfs_agf *agf; + xfs_agblock_t agend; + + error = xfs_alloc_read_agf(mp, tp, agno, 0, &agf_bp); + if (error) + break; + + cur = xfs_rmapbt_init_cursor(mp, tp, agf_bp, agf_bp->b_pag); + + /* + * Set the rmap range from ri_low to ri_high, which represents + * a [start, end] where we looking for the files or metadata. + * The part of range out of a AG will be ignored. So, it's fine + * to set ri_low to "startblock" in all loops. When it reaches + * the last AG, set the ri_high to "endblock" to make sure we + * actually end at the end. + */ + memset(&ri_high, 0xFF, sizeof(ri_high)); + ri_low.rm_startblock = XFS_FSB_TO_AGBNO(mp, fsbno); + if (agno == end_agno) + ri_high.rm_startblock = XFS_FSB_TO_AGBNO(mp, end_fsbno); + + agf = agf_bp->b_addr; + agend = min(be32_to_cpu(agf->agf_length), + ri_high.rm_startblock); + notify.startblock = ri_low.rm_startblock; + notify.blockcount = agend - ri_low.rm_startblock; + + error = xfs_rmap_query_range(cur, &ri_low, &ri_high, + xfs_dax_failure_fn, ¬ify); + xfs_btree_del_cursor(cur, error); + xfs_trans_brelse(tp, agf_bp); + if (error) + break; + + fsbno = XFS_AGB_TO_FSB(mp, agno + 1, 0); + } + + xfs_trans_cancel(tp); + return error; +} + +static int +xfs_dax_notify_failure( + struct dax_device *dax_dev, + u64 offset, + u64 len, + int mf_flags) +{ + struct xfs_mount *mp = dax_holder(dax_dev); + u64 ddev_start; + u64 ddev_end; + + if (mp->m_rtdev_targp && mp->m_rtdev_targp->bt_daxdev == dax_dev) { + xfs_warn(mp, + "notify_failure() not supported on realtime device!"); + return -EOPNOTSUPP; + } + + if (mp->m_logdev_targp && mp->m_logdev_targp->bt_daxdev == dax_dev && + mp->m_logdev_targp != mp->m_ddev_targp) { + xfs_err(mp, "ondisk log corrupt, shutting down fs!"); + xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_ONDISK); + return -EFSCORRUPTED; + } + + if (!xfs_has_rmapbt(mp)) { + xfs_warn(mp, "notify_failure() needs rmapbt enabled!"); + return -EOPNOTSUPP; + } + + ddev_start = mp->m_ddev_targp->bt_dax_part_off; + ddev_end = ddev_start + bdev_nr_bytes(mp->m_ddev_targp->bt_bdev) - 1; + + /* Ignore the range out of filesystem area */ + if (offset + len < ddev_start) + return -ENXIO; + if (offset > ddev_end) + return -ENXIO; + + /* Calculate the real range when it touches the boundary */ + if (offset > ddev_start) + offset -= ddev_start; + else { + len -= ddev_start - offset; + offset = 0; + } + if (offset + len > ddev_end) + len -= ddev_end - offset; + + return xfs_dax_notify_ddev_failure(mp, BTOBB(offset), BTOBB(len), + mf_flags); +} + +const struct dax_holder_operations xfs_dax_holder_operations = { + .notify_failure = xfs_dax_notify_failure, +}; diff --git a/fs/xfs/xfs_super.h b/fs/xfs/xfs_super.h index 167d23f92ffe..27ab5087d0b3 100644 --- a/fs/xfs/xfs_super.h +++ b/fs/xfs/xfs_super.h @@ -93,6 +93,7 @@ extern xfs_agnumber_t xfs_set_inode_alloc(struct xfs_mount *, extern const struct export_operations xfs_export_operations; extern const struct xattr_handler *xfs_xattr_handlers[]; extern const struct quotactl_ops xfs_quotactl_operations; +extern const struct dax_holder_operations xfs_dax_holder_operations; extern void xfs_reinit_percpu_counters(struct xfs_mount *mp); From patchwork Sun Apr 10 16:09:04 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shiyang Ruan X-Patchwork-Id: 12808195 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9EEFBC433EF for ; Sun, 10 Apr 2022 16:09:23 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C0CB78D0003; 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d="scan'208";a="123453821" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 11 Apr 2022 00:09:14 +0800 Received: from G08CNEXMBPEKD04.g08.fujitsu.local (unknown [10.167.33.201]) by cn.fujitsu.com (Postfix) with ESMTP id 6D5BA4D17168; Mon, 11 Apr 2022 00:09:10 +0800 (CST) Received: from G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.85) by G08CNEXMBPEKD04.g08.fujitsu.local (10.167.33.201) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Mon, 11 Apr 2022 00:09:13 +0800 Received: from irides.mr.mr (10.167.225.141) by G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.209) with Microsoft SMTP Server id 15.0.1497.23 via Frontend Transport; Mon, 11 Apr 2022 00:09:09 +0800 From: Shiyang Ruan To: , , , , CC: , , , , Subject: [PATCH v12 7/7] fsdax: set a CoW flag when associate reflink mappings Date: Mon, 11 Apr 2022 00:09:04 +0800 Message-ID: <20220410160904.3758789-8-ruansy.fnst@fujitsu.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220410160904.3758789-1-ruansy.fnst@fujitsu.com> References: <20220410160904.3758789-1-ruansy.fnst@fujitsu.com> MIME-Version: 1.0 X-yoursite-MailScanner-ID: 6D5BA4D17168.A0E9E X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: ruansy.fnst@fujitsu.com X-Stat-Signature: 9aupyjsjdes68d4romsh5xnsjt41dqr8 Authentication-Results: imf28.hostedemail.com; dkim=none; spf=none (imf28.hostedemail.com: domain of ruansy.fnst@fujitsu.com has no SPF policy when checking 183.91.158.132) smtp.mailfrom=ruansy.fnst@fujitsu.com; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=fujitsu.com (policy=none) X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: CC9C1C0009 X-HE-Tag: 1649606957-934302 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Introduce a PAGE_MAPPING_DAX_COW flag to support association with CoW file mappings. In this case, since the dax-rmap has already took the responsibility to look up for shared files by given dax page, the page->mapping is no longer to used for rmap but for marking that this dax page is shared. And to make sure disassociation works fine, we use page->index as refcount, and clear page->mapping to the initial state when page->index is decreased to 0. With the help of this new flag, it is able to distinguish normal case and CoW case, and keep the warning in normal case. == PS: The @cow added for dax_associate_entry(), is used to let it know whether the entry is to be shared during iomap operation. It is decided by iomap,srcmap's flag, and will be used in another patchset( fsdax,xfs: Add reflink&dedupe support for fsdax[1]). In this patch, we set @cow always false for now. [1] https://lore.kernel.org/linux-xfs/20210928062311.4012070-1-ruansy.fnst@fujitsu.com/ == Signed-off-by: Shiyang Ruan --- fs/dax.c | 65 ++++++++++++++++++++++++++++++++------ include/linux/page-flags.h | 6 ++++ 2 files changed, 62 insertions(+), 9 deletions(-) diff --git a/fs/dax.c b/fs/dax.c index 57efd3f73655..2c2958425b95 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -334,13 +334,46 @@ static unsigned long dax_end_pfn(void *entry) for (pfn = dax_to_pfn(entry); \ pfn < dax_end_pfn(entry); pfn++) +static inline void dax_mapping_set_cow_flag(struct address_space **mapping) +{ + *mapping = (struct address_space *)PAGE_MAPPING_DAX_COW; +} + +static inline bool dax_mapping_is_cow(struct address_space *mapping) +{ + return (unsigned long)mapping == PAGE_MAPPING_DAX_COW; +} + /* - * TODO: for reflink+dax we need a way to associate a single page with - * multiple address_space instances at different linear_page_index() - * offsets. + * Set or Update the page->mapping with FS_DAX_MAPPING_COW flag. + * Return true if it is an Update. + */ +static inline bool dax_mapping_set_cow(struct page *page) +{ + if (page->mapping) { + /* flag already set */ + if (dax_mapping_is_cow(page->mapping)) + return false; + + /* + * This page has been mapped even before it is shared, just + * need to set this FS_DAX_MAPPING_COW flag. + */ + dax_mapping_set_cow_flag(&page->mapping); + return true; + } + /* Newly associate CoW mapping */ + dax_mapping_set_cow_flag(&page->mapping); + return false; +} + +/* + * When it is called in dax_insert_entry(), the cow flag will indicate that + * whether this entry is shared by multiple files. If so, set the page->mapping + * to be FS_DAX_MAPPING_COW, and use page->index as refcount. */ static void dax_associate_entry(void *entry, struct address_space *mapping, - struct vm_area_struct *vma, unsigned long address) + struct vm_area_struct *vma, unsigned long address, bool cow) { unsigned long size = dax_entry_size(entry), pfn, index; int i = 0; @@ -352,9 +385,17 @@ static void dax_associate_entry(void *entry, struct address_space *mapping, for_each_mapped_pfn(entry, pfn) { struct page *page = pfn_to_page(pfn); - WARN_ON_ONCE(page->mapping); - page->mapping = mapping; - page->index = index + i++; + if (cow) { + if (dax_mapping_set_cow(page)) { + /* Was normal, now updated to CoW */ + page->index = 2; + } else + page->index++; + } else { + WARN_ON_ONCE(page->mapping); + page->mapping = mapping; + page->index = index + i++; + } } } @@ -370,7 +411,12 @@ static void dax_disassociate_entry(void *entry, struct address_space *mapping, struct page *page = pfn_to_page(pfn); WARN_ON_ONCE(trunc && page_ref_count(page) > 1); - WARN_ON_ONCE(page->mapping && page->mapping != mapping); + if (!dax_mapping_is_cow(page->mapping)) { + /* keep the CoW flag if this page is still shared */ + if (page->index-- > 0) + continue; + } else + WARN_ON_ONCE(page->mapping && page->mapping != mapping); page->mapping = NULL; page->index = 0; } @@ -829,7 +875,8 @@ static void *dax_insert_entry(struct xa_state *xas, void *old; dax_disassociate_entry(entry, mapping, false); - dax_associate_entry(new_entry, mapping, vmf->vma, vmf->address); + dax_associate_entry(new_entry, mapping, vmf->vma, vmf->address, + false); /* * Only swap our new entry into the page cache if the current * entry is a zero page or an empty entry. If a normal PTE or diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index b70124b9c7c1..e02907150e5c 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -650,6 +650,12 @@ __PAGEFLAG(Reported, reported, PF_NO_COMPOUND) #define PAGE_MAPPING_KSM (PAGE_MAPPING_ANON | PAGE_MAPPING_MOVABLE) #define PAGE_MAPPING_FLAGS (PAGE_MAPPING_ANON | PAGE_MAPPING_MOVABLE) +/* + * Different with flags above, this flag is used only for fsdax mode. It + * indicates that this page->mapping is now under reflink case. + */ +#define PAGE_MAPPING_DAX_COW 0x1 + static __always_inline int PageMappingFlags(struct page *page) { return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) != 0;