From patchwork Sun Dec 26 14:34:31 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shiyang Ruan X-Patchwork-Id: 12699340 Received: from heian.cn.fujitsu.com (mail.cn.fujitsu.com [183.91.158.132]) by smtp.subspace.kernel.org (Postfix) with ESMTP id E72572C9C for ; Sun, 26 Dec 2021 14:35:05 +0000 (UTC) IronPort-Data: A9a23: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 IronPort-HdrOrdr: A9a23:njpok6/PmNzmvIgRnXpuk+DkI+orL9Y04lQ7vn2ZKCYlFvBw8vrCoB1173HJYUkqMk3I9ergBEDiewK4yXcW2/hzAV7KZmCP11dAR7sSj7cKrQeBJwTOssZZ1YpFN5N1EcDMCzFB5vrS0U2VFMkBzbC8nJyVuQ== X-IronPort-AV: E=Sophos;i="5.88,237,1635177600"; d="scan'208";a="119563866" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 26 Dec 2021 22:35:04 +0800 Received: from G08CNEXMBPEKD04.g08.fujitsu.local (unknown [10.167.33.201]) by cn.fujitsu.com (Postfix) with ESMTP id 4AB594D146EE; Sun, 26 Dec 2021 22:35:03 +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; Sun, 26 Dec 2021 22:35:05 +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; Sun, 26 Dec 2021 22:35:01 +0800 From: Shiyang Ruan To: , , , , CC: , , , , Subject: [PATCH v9 02/10] dax: Introduce holder for dax_device Date: Sun, 26 Dec 2021 22:34:31 +0800 Message-ID: <20211226143439.3985960-3-ruansy.fnst@fujitsu.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211226143439.3985960-1-ruansy.fnst@fujitsu.com> References: <20211226143439.3985960-1-ruansy.fnst@fujitsu.com> Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-yoursite-MailScanner-ID: 4AB594D146EE.A03D7 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: ruansy.fnst@fujitsu.com X-Spam-Status: No 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 --- drivers/dax/super.c | 62 +++++++++++++++++++++++++++++++++++++++++++++ include/linux/dax.h | 29 +++++++++++++++++++++ 2 files changed, 91 insertions(+) diff --git a/drivers/dax/super.c b/drivers/dax/super.c index c46f56e33d40..94c51f2ee133 100644 --- a/drivers/dax/super.c +++ b/drivers/dax/super.c @@ -20,15 +20,20 @@ * @inode: core vfs * @cdev: optional character interface for "device dax" * @private: dax driver private data + * @holder_data: holder of a dax_device: could be filesystem or mapped device * @flags: state and boolean properties + * @ops: operations for dax_device + * @holder_ops: operations for the inner holder */ struct dax_device { struct inode inode; struct cdev cdev; void *private; struct percpu_rw_semaphore rwsem; + void *holder_data; unsigned long flags; const struct dax_operations *ops; + const struct dax_holder_operations *holder_ops; }; static dev_t dax_devt; @@ -192,6 +197,29 @@ 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; + + dax_read_lock(dax_dev); + 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(dax_dev); + 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) @@ -254,6 +282,10 @@ void kill_dax(struct dax_device *dax_dev) return; dax_write_lock(dax_dev); clear_bit(DAXDEV_ALIVE, &dax_dev->flags); + + /* clear holder data */ + dax_dev->holder_ops = NULL; + dax_dev->holder_data = NULL; dax_write_unlock(dax_dev); } EXPORT_SYMBOL_GPL(kill_dax); @@ -401,6 +433,36 @@ void put_dax(struct dax_device *dax_dev) } EXPORT_SYMBOL_GPL(put_dax); +void dax_register_holder(struct dax_device *dax_dev, void *holder, + const struct dax_holder_operations *ops) +{ + if (!dax_alive(dax_dev)) + return; + + dax_dev->holder_data = holder; + dax_dev->holder_ops = ops; +} +EXPORT_SYMBOL_GPL(dax_register_holder); + +void dax_unregister_holder(struct dax_device *dax_dev) +{ + if (!dax_alive(dax_dev)) + return; + + dax_dev->holder_data = NULL; + dax_dev->holder_ops = NULL; +} +EXPORT_SYMBOL_GPL(dax_unregister_holder); + +void *dax_get_holder(struct dax_device *dax_dev) +{ + if (!dax_alive(dax_dev)) + return NULL; + + return dax_dev->holder_data; +} +EXPORT_SYMBOL_GPL(dax_get_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/include/linux/dax.h b/include/linux/dax.h index a146bfb80804..e16a9e0ee857 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -44,6 +44,22 @@ struct dax_operations { #if IS_ENABLED(CONFIG_DAX) struct dax_device *alloc_dax(void *private, const struct dax_operations *ops, unsigned long flags); +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); +}; + +void dax_register_holder(struct dax_device *dax_dev, void *holder, + const struct dax_holder_operations *ops); +void dax_unregister_holder(struct dax_device *dax_dev); +void *dax_get_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); @@ -71,6 +87,17 @@ static inline bool daxdev_mapping_supported(struct vm_area_struct *vma, return dax_synchronous(dax_dev); } #else +static inline void dax_register_holder(struct dax_device *dax_dev, void *holder, + const struct dax_holder_operations *ops) +{ +} +static inline void dax_unregister_holder(struct dax_device *dax_dev) +{ +} +static inline void *dax_get_holder(struct dax_device *dax_dev) +{ + return NULL; +} static inline struct dax_device *alloc_dax(void *private, const struct dax_operations *ops, unsigned long flags) { @@ -209,6 +236,8 @@ 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,