[v11,17/26] block/rnbd: client: private header with client structs and functions

Commit Message

Jinpu Wang March 20, 2020, 12:16 p.m. UTC

This header describes main structs and functions used by rnbd-client
module, mainly for managing RNBD sessions and mapped block devices,
creating and destroying sysfs entries.

Signed-off-by: Danil Kipnis <[e-mail]>
Signed-off-by: Jack Wang <[e-mail]>
Reviewed-by: Bart Van Assche <[e-mail]>
---
 drivers/block/rnbd/rnbd-clt.h | 148 ++++++++++++++++++++++++++++++++++
 1 file changed, 148 insertions(+)
 create mode 100644 drivers/block/rnbd/rnbd-clt.h

Comments

Bart Van Assche March 28, 2020, 4:26 a.m. UTC | #1

On 2020-03-20 05:16, Jack Wang wrote:
> +#define BMAX_SEGMENTS 29
> +#define RECONNECT_DELAY 30
> +#define MAX_RECONNECTS -1

Please add a comment above each of these constants that explains the
role of these constants. I can guess what the purpose of the last two
constants is but not what the purpose of the first constant is.

Thanks,

Bart.

Jinpu Wang March 31, 2020, 9:08 a.m. UTC | #2

On Sat, Mar 28, 2020 at 5:26 AM Bart Van Assche <[e-mail]> wrote:
>
> On 2020-03-20 05:16, Jack Wang wrote:
> > +#define BMAX_SEGMENTS 29
> > +#define RECONNECT_DELAY 30
> > +#define MAX_RECONNECTS -1
>
> Please add a comment above each of these constants that explains the
> role of these constants. I can guess what the purpose of the last two
> constants is but not what the purpose of the first constant is.

Sure, will add comments for each of them.
Thanks!

Patch

diff --git a/drivers/block/rnbd/rnbd-clt.h b/drivers/block/rnbd/rnbd-clt.h
new file mode 100644
index 000000000000..276a3220f78f
--- /dev/null
+++ b/drivers/block/rnbd/rnbd-clt.h
@@ -0,0 +1,148 @@ 
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * RDMA Network Block Driver
+ *
+ * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
+ * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
+ * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
+ */
+
+#ifndef RNBD_CLT_H
+#define RNBD_CLT_H
+
+#include <linux/wait.h>
+#include <linux/in.h>
+#include <linux/inet.h>
+#include <linux/blk-mq.h>
+#include <linux/refcount.h>
+
+#include "rtrs.h"
+#include "rnbd-proto.h"
+#include "rnbd-log.h"
+
+#define BMAX_SEGMENTS 29
+#define RECONNECT_DELAY 30
+#define MAX_RECONNECTS -1
+
+enum rnbd_clt_dev_state {
+	DEV_STATE_INIT,
+	DEV_STATE_MAPPED,
+	DEV_STATE_MAPPED_DISCONNECTED,
+	DEV_STATE_UNMAPPED,
+};
+
+struct rnbd_iu_comp {
+	wait_queue_head_t wait;
+	int errno;
+};
+
+struct rnbd_iu {
+	union {
+		struct request *rq; /* for block io */
+		void *buf; /* for user messages */
+	};
+	struct rtrs_permit	*permit;
+	union {
+		/* use to send msg associated with a dev */
+		struct rnbd_clt_dev *dev;
+		/* use to send msg associated with a sess */
+		struct rnbd_clt_session *sess;
+	};
+	struct scatterlist	sglist[BMAX_SEGMENTS];
+	struct work_struct	work;
+	int			errno;
+	struct rnbd_iu_comp	comp;
+	atomic_t		refcount;
+};
+
+struct rnbd_cpu_qlist {
+	struct list_head	requeue_list;
+	spinlock_t		requeue_lock;
+	unsigned int		cpu;
+};
+
+struct rnbd_clt_session {
+	struct list_head        list;
+	struct rtrs_clt        *rtrs;
+	wait_queue_head_t       rtrs_waitq;
+	bool                    rtrs_ready;
+	struct rnbd_cpu_qlist	__percpu
+				*cpu_queues;
+	DECLARE_BITMAP(cpu_queues_bm, NR_CPUS);
+	int	__percpu	*cpu_rr; /* per-cpu var for CPU round-robin */
+	atomic_t		busy;
+	int			queue_depth;
+	u32			max_io_size;
+	struct blk_mq_tag_set	tag_set;
+	struct mutex		lock; /* protects state and devs_list */
+	struct list_head        devs_list; /* list of struct rnbd_clt_dev */
+	refcount_t		refcount;
+	char			sessname[NAME_MAX];
+	u8			ver; /* protocol version */
+};
+
+/**
+ * Submission queues.
+ */
+struct rnbd_queue {
+	struct list_head	requeue_list;
+	unsigned long		in_list;
+	struct rnbd_clt_dev	*dev;
+	struct blk_mq_hw_ctx	*hctx;
+};
+
+struct rnbd_clt_dev {
+	struct rnbd_clt_session	*sess;
+	struct request_queue	*queue;
+	struct rnbd_queue	*hw_queues;
+	u32			device_id;
+	/* local Idr index - used to track minor number allocations. */
+	u32			clt_device_id;
+	struct mutex		lock;
+	enum rnbd_clt_dev_state	dev_state;
+	char			pathname[NAME_MAX];
+	enum rnbd_access_mode	access_mode;
+	bool			read_only;
+	bool			rotational;
+	u32			max_hw_sectors;
+	u32			max_write_same_sectors;
+	u32			max_discard_sectors;
+	u32			discard_granularity;
+	u32			discard_alignment;
+	u16			secure_discard;
+	u16			physical_block_size;
+	u16			logical_block_size;
+	u16			max_segments;
+	size_t			nsectors;
+	u64			size;		/* device size in bytes */
+	struct list_head        list;
+	struct gendisk		*gd;
+	struct kobject		kobj;
+	char			blk_symlink_name[NAME_MAX];
+	refcount_t		refcount;
+	struct work_struct	unmap_on_rmmod_work;
+};
+
+/* rnbd-clt.c */
+
+struct rnbd_clt_dev *rnbd_clt_map_device(const char *sessname,
+					   struct rtrs_addr *paths,
+					   size_t path_cnt,
+					   const char *pathname,
+					   enum rnbd_access_mode access_mode);
+int rnbd_clt_unmap_device(struct rnbd_clt_dev *dev, bool force,
+			   const struct attribute *sysfs_self);
+
+int rnbd_clt_remap_device(struct rnbd_clt_dev *dev);
+int rnbd_clt_resize_disk(struct rnbd_clt_dev *dev, size_t newsize);
+
+/* rnbd-clt-sysfs.c */
+
+int rnbd_clt_create_sysfs_files(void);
+
+void rnbd_clt_destroy_sysfs_files(void);
+void rnbd_clt_destroy_default_group(void);
+
+void rnbd_clt_remove_dev_symlink(struct rnbd_clt_dev *dev);
+
+#endif /* RNBD_CLT_H */