summaryrefslogtreecommitdiffstats
path: root/fs/nfs/blocklayout/blocklayout.h
blob: f27d827960a390dede9602f3d8196dce32d8eb8a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
/*
 *  linux/fs/nfs/blocklayout/blocklayout.h
 *
 *  Module for the NFSv4.1 pNFS block layout driver.
 *
 *  Copyright (c) 2006 The Regents of the University of Michigan.
 *  All rights reserved.
 *
 *  Andy Adamson <andros@citi.umich.edu>
 *  Fred Isaman <iisaman@umich.edu>
 *
 * permission is granted to use, copy, create derivative works and
 * redistribute this software and such derivative works for any purpose,
 * so long as the name of the university of michigan is not used in
 * any advertising or publicity pertaining to the use or distribution
 * of this software without specific, written prior authorization.  if
 * the above copyright notice or any other identification of the
 * university of michigan is included in any copy of any portion of
 * this software, then the disclaimer below must also be included.
 *
 * this software is provided as is, without representation from the
 * university of michigan as to its fitness for any purpose, and without
 * warranty by the university of michigan of any kind, either express
 * or implied, including without limitation the implied warranties of
 * merchantability and fitness for a particular purpose.  the regents
 * of the university of michigan shall not be liable for any damages,
 * including special, indirect, incidental, or consequential damages,
 * with respect to any claim arising out or in connection with the use
 * of the software, even if it has been or is hereafter advised of the
 * possibility of such damages.
 */
#ifndef FS_NFS_NFS4BLOCKLAYOUT_H
#define FS_NFS_NFS4BLOCKLAYOUT_H

#include <linux/device-mapper.h>
#include <linux/nfs_fs.h>
#include <linux/sunrpc/rpc_pipe_fs.h>

#include "../pnfs.h"

#define PAGE_CACHE_SECTORS (PAGE_CACHE_SIZE >> SECTOR_SHIFT)
#define PAGE_CACHE_SECTOR_SHIFT (PAGE_CACHE_SHIFT - SECTOR_SHIFT)

struct block_mount_id {
	spinlock_t			bm_lock;    /* protects list */
	struct list_head		bm_devlist; /* holds pnfs_block_dev */
};

struct pnfs_block_dev {
	struct list_head		bm_node;
	struct nfs4_deviceid		bm_mdevid;    /* associated devid */
	struct block_device		*bm_mdev;     /* meta device itself */
};

enum exstate4 {
	PNFS_BLOCK_READWRITE_DATA	= 0,
	PNFS_BLOCK_READ_DATA		= 1,
	PNFS_BLOCK_INVALID_DATA		= 2, /* mapped, but data is invalid */
	PNFS_BLOCK_NONE_DATA		= 3  /* unmapped, it's a hole */
};

#define MY_MAX_TAGS (15) /* tag bitnums used must be less than this */

struct my_tree {
	sector_t		mtt_step_size;	/* Internal sector alignment */
	struct list_head	mtt_stub; /* Should be a radix tree */
};

struct pnfs_inval_markings {
	spinlock_t	im_lock;
	struct my_tree	im_tree;	/* Sectors that need LAYOUTCOMMIT */
	sector_t	im_block_size;	/* Server blocksize in sectors */
};

struct pnfs_inval_tracking {
	struct list_head it_link;
	int		 it_sector;
	int		 it_tags;
};

/* sector_t fields are all in 512-byte sectors */
struct pnfs_block_extent {
	struct kref	be_refcnt;
	struct list_head be_node;	/* link into lseg list */
	struct nfs4_deviceid be_devid;  /* FIXME: could use device cache instead */
	struct block_device *be_mdev;
	sector_t	be_f_offset;	/* the starting offset in the file */
	sector_t	be_length;	/* the size of the extent */
	sector_t	be_v_offset;	/* the starting offset in the volume */
	enum exstate4	be_state;	/* the state of this extent */
	struct pnfs_inval_markings *be_inval; /* tracks INVAL->RW transition */
};

/* Shortened extent used by LAYOUTCOMMIT */
struct pnfs_block_short_extent {
	struct list_head bse_node;
	struct nfs4_deviceid bse_devid;
	struct block_device *bse_mdev;
	sector_t	bse_f_offset;	/* the starting offset in the file */
	sector_t	bse_length;	/* the size of the extent */
};

static inline void
BL_INIT_INVAL_MARKS(struct pnfs_inval_markings *marks, sector_t blocksize)
{
	spin_lock_init(&marks->im_lock);
	INIT_LIST_HEAD(&marks->im_tree.mtt_stub);
	marks->im_block_size = blocksize;
	marks->im_tree.mtt_step_size = min((sector_t)PAGE_CACHE_SECTORS,
					   blocksize);
}

enum extentclass4 {
	RW_EXTENT       = 0, /* READWRTE and INVAL */
	RO_EXTENT       = 1, /* READ and NONE */
	EXTENT_LISTS    = 2,
};

static inline int bl_choose_list(enum exstate4 state)
{
	if (state == PNFS_BLOCK_READ_DATA || state == PNFS_BLOCK_NONE_DATA)
		return RO_EXTENT;
	else
		return RW_EXTENT;
}

struct pnfs_block_layout {
	struct pnfs_layout_hdr bl_layout;
	struct pnfs_inval_markings bl_inval; /* tracks INVAL->RW transition */
	spinlock_t		bl_ext_lock;   /* Protects list manipulation */
	struct list_head	bl_extents[EXTENT_LISTS]; /* R and RW extents */
	struct list_head	bl_commit;	/* Needs layout commit */
	struct list_head	bl_committing;	/* Layout committing */
	unsigned int		bl_count;	/* entries in bl_commit */
	sector_t		bl_blocksize;  /* Server blocksize in sectors */
};

#define BLK_ID(lo) ((struct block_mount_id *)(NFS_SERVER(lo->plh_inode)->pnfs_ld_data))

static inline struct pnfs_block_layout *
BLK_LO2EXT(struct pnfs_layout_hdr *lo)
{
	return container_of(lo, struct pnfs_block_layout, bl_layout);
}

static inline struct pnfs_block_layout *
BLK_LSEG2EXT(struct pnfs_layout_segment *lseg)
{
	return BLK_LO2EXT(lseg->pls_layout);
}

struct bl_dev_msg {
	int status;
	uint32_t major, minor;
};

struct bl_msg_hdr {
	u8  type;
	u16 totallen; /* length of entire message, including hdr itself */
};

extern struct dentry *bl_device_pipe;
extern wait_queue_head_t bl_wq;

#define BL_DEVICE_UMOUNT               0x0 /* Umount--delete devices */
#define BL_DEVICE_MOUNT                0x1 /* Mount--create devices*/
#define BL_DEVICE_REQUEST_INIT         0x0 /* Start request */
#define BL_DEVICE_REQUEST_PROC         0x1 /* User level process succeeds */
#define BL_DEVICE_REQUEST_ERR          0x2 /* User level process fails */

/* blocklayoutdev.c */
ssize_t bl_pipe_upcall(struct file *, struct rpc_pipe_msg *,
		       char __user *, size_t);
ssize_t bl_pipe_downcall(struct file *, const char __user *, size_t);
void bl_pipe_destroy_msg(struct rpc_pipe_msg *);
struct block_device *nfs4_blkdev_get(dev_t dev);
int nfs4_blkdev_put(struct block_device *bdev);
struct pnfs_block_dev *nfs4_blk_decode_device(struct nfs_server *server,
						struct pnfs_device *dev);
int nfs4_blk_process_layoutget(struct pnfs_layout_hdr *lo,
				struct nfs4_layoutget_res *lgr, gfp_t gfp_flags);

/* blocklayoutdm.c */
void bl_free_block_dev(struct pnfs_block_dev *bdev);

/* extents.c */
struct pnfs_block_extent *
bl_find_get_extent(struct pnfs_block_layout *bl, sector_t isect,
		struct pnfs_block_extent **cow_read);
int bl_mark_sectors_init(struct pnfs_inval_markings *marks,
			     sector_t offset, sector_t length,
			     sector_t **pages);
void bl_put_extent(struct pnfs_block_extent *be);
struct pnfs_block_extent *bl_alloc_extent(void);
int bl_is_sector_init(struct pnfs_inval_markings *marks, sector_t isect);
int encode_pnfs_block_layoutupdate(struct pnfs_block_layout *bl,
				   struct xdr_stream *xdr,
				   const struct nfs4_layoutcommit_args *arg);
void clean_pnfs_block_layoutupdate(struct pnfs_block_layout *bl,
				   const struct nfs4_layoutcommit_args *arg,
				   int status);
int bl_add_merge_extent(struct pnfs_block_layout *bl,
			 struct pnfs_block_extent *new);
int bl_mark_for_commit(struct pnfs_block_extent *be,
			sector_t offset, sector_t length);

#endif /* FS_NFS_NFS4BLOCKLAYOUT_H */