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_SIZE >> SECTOR_SHIFT)
44#define PAGE_CACHE_SECTOR_SHIFT (PAGE_SHIFT - SECTOR_SHIFT)
45#define SECTOR_SIZE (1 << SECTOR_SHIFT)
46
47struct pnfs_block_dev;
48
49#define PNFS_BLOCK_MAX_UUIDS	4
50#define PNFS_BLOCK_MAX_DEVICES	64
51
52/*
53 * Random upper cap for the uuid length to avoid unbounded allocation.
54 * Not actually limited by the protocol.
55 */
56#define PNFS_BLOCK_UUID_LEN	128
57
58struct pnfs_block_volume {
59	enum pnfs_block_volume_type	type;
60	union {
61		struct {
62			int		len;
63			int		nr_sigs;
64			struct {
65				u64		offset;
66				u32		sig_len;
67				u8		sig[PNFS_BLOCK_UUID_LEN];
68			} sigs[PNFS_BLOCK_MAX_UUIDS];
69		} simple;
70		struct {
71			u64		start;
72			u64		len;
73			u32		volume;
74		} slice;
75		struct {
76			u32		volumes_count;
77			u32		volumes[PNFS_BLOCK_MAX_DEVICES];
78		} concat;
79		struct {
80			u64		chunk_size;
81			u32		volumes_count;
82			u32		volumes[PNFS_BLOCK_MAX_DEVICES];
83		} stripe;
84		struct {
85			enum scsi_code_set		code_set;
86			enum scsi_designator_type	designator_type;
87			int				designator_len;
88			u8				designator[256];
89			u64				pr_key;
90		} scsi;
91	};
92};
93
94struct pnfs_block_dev_map {
95	u64			start;
96	u64			len;
97	u64			disk_offset;
98	struct block_device		*bdev;
99};
100
101struct pnfs_block_dev {
102	struct nfs4_deviceid_node	node;
103
104	u64				start;
105	u64				len;
106
107	u32				nr_children;
108	struct pnfs_block_dev		*children;
109	u64				chunk_size;
110
111	struct block_device		*bdev;
112	u64				disk_offset;
113
114	u64				pr_key;
115	bool				pr_registered;
116
117	bool (*map)(struct pnfs_block_dev *dev, u64 offset,
118			struct pnfs_block_dev_map *map);
119};
120
121/* sector_t fields are all in 512-byte sectors */
122struct pnfs_block_extent {
123	union {
124		struct rb_node	be_node;
125		struct list_head be_list;
126	};
127	struct nfs4_deviceid_node *be_device;
128	sector_t	be_f_offset;	/* the starting offset in the file */
129	sector_t	be_length;	/* the size of the extent */
130	sector_t	be_v_offset;	/* the starting offset in the volume */
131	enum pnfs_block_extent_state be_state;	/* the state of this extent */
132#define EXTENT_WRITTEN		1
133#define EXTENT_COMMITTING	2
134	unsigned int	be_tag;
135};
136
137struct pnfs_block_layout {
138	struct pnfs_layout_hdr	bl_layout;
139	struct rb_root		bl_ext_rw;
140	struct rb_root		bl_ext_ro;
141	spinlock_t		bl_ext_lock;   /* Protects list manipulation */
142	bool			bl_scsi_layout;
143	u64			bl_lwb;
144};
145
146static inline struct pnfs_block_layout *
147BLK_LO2EXT(struct pnfs_layout_hdr *lo)
148{
149	return container_of(lo, struct pnfs_block_layout, bl_layout);
150}
151
152static inline struct pnfs_block_layout *
153BLK_LSEG2EXT(struct pnfs_layout_segment *lseg)
154{
155	return BLK_LO2EXT(lseg->pls_layout);
156}
157
158struct bl_pipe_msg {
159	struct rpc_pipe_msg msg;
160	wait_queue_head_t *bl_wq;
161};
162
163struct bl_msg_hdr {
164	u8  type;
165	u16 totallen; /* length of entire message, including hdr itself */
166};
167
168#define BL_DEVICE_UMOUNT               0x0 /* Umount--delete devices */
169#define BL_DEVICE_MOUNT                0x1 /* Mount--create devices*/
170#define BL_DEVICE_REQUEST_INIT         0x0 /* Start request */
171#define BL_DEVICE_REQUEST_PROC         0x1 /* User level process succeeds */
172#define BL_DEVICE_REQUEST_ERR          0x2 /* User level process fails */
173
174/* dev.c */
175struct nfs4_deviceid_node *bl_alloc_deviceid_node(struct nfs_server *server,
176		struct pnfs_device *pdev, gfp_t gfp_mask);
177void bl_free_deviceid_node(struct nfs4_deviceid_node *d);
178
179/* extent_tree.c */
180int ext_tree_insert(struct pnfs_block_layout *bl,
181		struct pnfs_block_extent *new);
182int ext_tree_remove(struct pnfs_block_layout *bl, bool rw, sector_t start,
183		sector_t end);
184int ext_tree_mark_written(struct pnfs_block_layout *bl, sector_t start,
185		sector_t len, u64 lwb);
186bool ext_tree_lookup(struct pnfs_block_layout *bl, sector_t isect,
187		struct pnfs_block_extent *ret, bool rw);
188int ext_tree_prepare_commit(struct nfs4_layoutcommit_args *arg);
189void ext_tree_mark_committed(struct nfs4_layoutcommit_args *arg, int status);
190
191/* rpc_pipefs.c */
192dev_t bl_resolve_deviceid(struct nfs_server *server,
193		struct pnfs_block_volume *b, gfp_t gfp_mask);
194int __init bl_init_pipefs(void);
195void bl_cleanup_pipefs(void);
196
197#endif /* FS_NFS_NFS4BLOCKLAYOUT_H */
198