1/*
2 *  linux/fs/nfs/blocklayout/blocklayout.h
3 *
4 *  Module for the NFSv4.1 pNFS block layout driver.
5 *
6 *  Copyright (c) 2006 The Regents of the University of Michigan.
7 *  All rights reserved.
8 *
9 *  Andy Adamson <andros@citi.umich.edu>
10 *  Fred Isaman <iisaman@umich.edu>
11 *
12 * permission is granted to use, copy, create derivative works and
13 * redistribute this software and such derivative works for any purpose,
14 * so long as the name of the university of michigan is not used in
15 * any advertising or publicity pertaining to the use or distribution
16 * of this software without specific, written prior authorization.  if
17 * the above copyright notice or any other identification of the
18 * university of michigan is included in any copy of any portion of
19 * this software, then the disclaimer below must also be included.
20 *
21 * this software is provided as is, without representation from the
22 * university of michigan as to its fitness for any purpose, and without
23 * warranty by the university of michigan of any kind, either express
24 * or implied, including without limitation the implied warranties of
25 * merchantability and fitness for a particular purpose.  the regents
26 * of the university of michigan shall not be liable for any damages,
27 * including special, indirect, incidental, or consequential damages,
28 * with respect to any claim arising out or in connection with the use
29 * of the software, even if it has been or is hereafter advised of the
30 * possibility of such damages.
31 */
32#ifndef FS_NFS_NFS4BLOCKLAYOUT_H
33#define FS_NFS_NFS4BLOCKLAYOUT_H
34
35#include <linux/device-mapper.h>
36#include <linux/nfs_fs.h>
37#include <linux/sunrpc/rpc_pipe_fs.h>
38
39#include "../nfs4_fs.h"
40#include "../pnfs.h"
41#include "../netns.h"
42
43#define PAGE_CACHE_SECTORS (PAGE_CACHE_SIZE >> SECTOR_SHIFT)
44#define PAGE_CACHE_SECTOR_SHIFT (PAGE_CACHE_SHIFT - SECTOR_SHIFT)
45#define SECTOR_SIZE (1 << SECTOR_SHIFT)
46
47struct pnfs_block_dev;
48
49enum pnfs_block_volume_type {
50	PNFS_BLOCK_VOLUME_SIMPLE	= 0,
51	PNFS_BLOCK_VOLUME_SLICE		= 1,
52	PNFS_BLOCK_VOLUME_CONCAT	= 2,
53	PNFS_BLOCK_VOLUME_STRIPE	= 3,
54};
55
56#define PNFS_BLOCK_MAX_UUIDS	4
57#define PNFS_BLOCK_MAX_DEVICES	64
58
59/*
60 * Random upper cap for the uuid length to avoid unbounded allocation.
61 * Not actually limited by the protocol.
62 */
63#define PNFS_BLOCK_UUID_LEN	128
64
65
66struct pnfs_block_volume {
67	enum pnfs_block_volume_type	type;
68	union {
69		struct {
70			int		len;
71			int		nr_sigs;
72			struct {
73				u64		offset;
74				u32		sig_len;
75				u8		sig[PNFS_BLOCK_UUID_LEN];
76			} sigs[PNFS_BLOCK_MAX_UUIDS];
77		} simple;
78		struct {
79			u64		start;
80			u64		len;
81			u32		volume;
82		} slice;
83		struct {
84			u32		volumes_count;
85			u32		volumes[PNFS_BLOCK_MAX_DEVICES];
86		} concat;
87		struct {
88			u64		chunk_size;
89			u32		volumes_count;
90			u32		volumes[PNFS_BLOCK_MAX_DEVICES];
91		} stripe;
92	};
93};
94
95struct pnfs_block_dev_map {
96	sector_t			start;
97	sector_t			len;
98
99	sector_t			disk_offset;
100	struct block_device		*bdev;
101};
102
103struct pnfs_block_dev {
104	struct nfs4_deviceid_node	node;
105
106	u64				start;
107	u64				len;
108
109	u32				nr_children;
110	struct pnfs_block_dev		*children;
111	u64				chunk_size;
112
113	struct block_device		*bdev;
114	u64				disk_offset;
115
116	bool (*map)(struct pnfs_block_dev *dev, u64 offset,
117			struct pnfs_block_dev_map *map);
118};
119
120enum exstate4 {
121	PNFS_BLOCK_READWRITE_DATA	= 0,
122	PNFS_BLOCK_READ_DATA		= 1,
123	PNFS_BLOCK_INVALID_DATA		= 2, /* mapped, but data is invalid */
124	PNFS_BLOCK_NONE_DATA		= 3  /* unmapped, it's a hole */
125};
126
127/* sector_t fields are all in 512-byte sectors */
128struct pnfs_block_extent {
129	union {
130		struct rb_node	be_node;
131		struct list_head be_list;
132	};
133	struct nfs4_deviceid_node *be_device;
134	sector_t	be_f_offset;	/* the starting offset in the file */
135	sector_t	be_length;	/* the size of the extent */
136	sector_t	be_v_offset;	/* the starting offset in the volume */
137	enum exstate4	be_state;	/* the state of this extent */
138#define EXTENT_WRITTEN		1
139#define EXTENT_COMMITTING	2
140	unsigned int	be_tag;
141};
142
143/* on the wire size of the extent */
144#define BL_EXTENT_SIZE	(7 * sizeof(__be32) + NFS4_DEVICEID4_SIZE)
145
146struct pnfs_block_layout {
147	struct pnfs_layout_hdr	bl_layout;
148	struct rb_root		bl_ext_rw;
149	struct rb_root		bl_ext_ro;
150	spinlock_t		bl_ext_lock;   /* Protects list manipulation */
151};
152
153static inline struct pnfs_block_layout *
154BLK_LO2EXT(struct pnfs_layout_hdr *lo)
155{
156	return container_of(lo, struct pnfs_block_layout, bl_layout);
157}
158
159static inline struct pnfs_block_layout *
160BLK_LSEG2EXT(struct pnfs_layout_segment *lseg)
161{
162	return BLK_LO2EXT(lseg->pls_layout);
163}
164
165struct bl_pipe_msg {
166	struct rpc_pipe_msg msg;
167	wait_queue_head_t *bl_wq;
168};
169
170struct bl_msg_hdr {
171	u8  type;
172	u16 totallen; /* length of entire message, including hdr itself */
173};
174
175#define BL_DEVICE_UMOUNT               0x0 /* Umount--delete devices */
176#define BL_DEVICE_MOUNT                0x1 /* Mount--create devices*/
177#define BL_DEVICE_REQUEST_INIT         0x0 /* Start request */
178#define BL_DEVICE_REQUEST_PROC         0x1 /* User level process succeeds */
179#define BL_DEVICE_REQUEST_ERR          0x2 /* User level process fails */
180
181/* dev.c */
182struct nfs4_deviceid_node *bl_alloc_deviceid_node(struct nfs_server *server,
183		struct pnfs_device *pdev, gfp_t gfp_mask);
184void bl_free_deviceid_node(struct nfs4_deviceid_node *d);
185
186/* extent_tree.c */
187int ext_tree_insert(struct pnfs_block_layout *bl,
188		struct pnfs_block_extent *new);
189int ext_tree_remove(struct pnfs_block_layout *bl, bool rw, sector_t start,
190		sector_t end);
191int ext_tree_mark_written(struct pnfs_block_layout *bl, sector_t start,
192		sector_t len);
193bool ext_tree_lookup(struct pnfs_block_layout *bl, sector_t isect,
194		struct pnfs_block_extent *ret, bool rw);
195int ext_tree_prepare_commit(struct nfs4_layoutcommit_args *arg);
196void ext_tree_mark_committed(struct nfs4_layoutcommit_args *arg, int status);
197
198/* rpc_pipefs.c */
199dev_t bl_resolve_deviceid(struct nfs_server *server,
200		struct pnfs_block_volume *b, gfp_t gfp_mask);
201int __init bl_init_pipefs(void);
202void __exit bl_cleanup_pipefs(void);
203
204#endif /* FS_NFS_NFS4BLOCKLAYOUT_H */
205