1/*
2 * NFSv4 file layout driver data structures.
3 *
4 * Copyright (c) 2002
5 * The Regents of the University of Michigan
6 * All Rights Reserved
7 *
8 * Dean Hildebrand <dhildebz@umich.edu>
9 *
10 * Permission is granted to use, copy, create derivative works, and
11 * redistribute this software and such derivative works for any purpose,
12 * so long as the name of the University of Michigan is not used in
13 * any advertising or publicity pertaining to the use or distribution
14 * of this software without specific, written prior authorization. If
15 * the above copyright notice or any other identification of the
16 * University of Michigan is included in any copy of any portion of
17 * this software, then the disclaimer below must also be included.
18 *
19 * This software is provided as is, without representation or warranty
20 * of any kind either express or implied, including without limitation
21 * the implied warranties of merchantability, fitness for a particular
22 * purpose, or noninfringement. The Regents of the University of
23 * Michigan shall not be liable for any damages, including special,
24 * indirect, incidental, or consequential damages, with respect to any
25 * claim arising out of or in connection with the use of the software,
26 * even if it has been or is hereafter advised of the possibility of
27 * such damages.
28 */
29
30#ifndef FS_NFS_NFS4FILELAYOUT_H
31#define FS_NFS_NFS4FILELAYOUT_H
32
33#include "../pnfs.h"
34
35/*
36 * Field testing shows we need to support up to 4096 stripe indices.
37 * We store each index as a u8 (u32 on the wire) to keep the memory footprint
38 * reasonable. This in turn means we support a maximum of 256
39 * RFC 5661 multipath_list4 structures.
40 */
41#define NFS4_PNFS_MAX_STRIPE_CNT 4096
42#define NFS4_PNFS_MAX_MULTI_CNT 256 /* 256 fit into a u8 stripe_index */
43
44enum stripetype4 {
45 STRIPE_SPARSE = 1,
46 STRIPE_DENSE = 2
47};
48
49struct nfs4_file_layout_dsaddr {
50 struct nfs4_deviceid_node id_node;
51 u32 stripe_count;
52 u8 *stripe_indices;
53 u32 ds_num;
54 struct nfs4_pnfs_ds *ds_list[] __counted_by(ds_num);
55};
56
57struct nfs4_filelayout_segment {
58 struct pnfs_layout_segment generic_hdr;
59 u32 stripe_type;
60 u32 commit_through_mds;
61 u32 stripe_unit;
62 u32 first_stripe_index;
63 u64 pattern_offset;
64 struct nfs4_deviceid deviceid;
65 struct nfs4_file_layout_dsaddr *dsaddr; /* Point to GETDEVINFO data */
66 unsigned int num_fh;
67 struct nfs_fh **fh_array;
68};
69
70struct nfs4_filelayout {
71 struct pnfs_layout_hdr generic_hdr;
72 struct pnfs_ds_commit_info commit_info;
73};
74
75static inline struct nfs4_filelayout *
76FILELAYOUT_FROM_HDR(struct pnfs_layout_hdr *lo)
77{
78 return container_of(lo, struct nfs4_filelayout, generic_hdr);
79}
80
81static inline struct nfs4_filelayout_segment *
82FILELAYOUT_LSEG(struct pnfs_layout_segment *lseg)
83{
84 return container_of(lseg,
85 struct nfs4_filelayout_segment,
86 generic_hdr);
87}
88
89static inline struct nfs4_deviceid_node *
90FILELAYOUT_DEVID_NODE(struct pnfs_layout_segment *lseg)
91{
92 return &FILELAYOUT_LSEG(lseg)->dsaddr->id_node;
93}
94
95static inline bool
96filelayout_test_devid_invalid(struct nfs4_deviceid_node *node)
97{
98 return test_bit(NFS_DEVICEID_INVALID, &node->flags);
99}
100
101extern bool
102filelayout_test_devid_unavailable(struct nfs4_deviceid_node *node);
103
104extern struct nfs_fh *
105nfs4_fl_select_ds_fh(struct pnfs_layout_segment *lseg, u32 j);
106
107u32 nfs4_fl_calc_j_index(struct pnfs_layout_segment *lseg, loff_t offset);
108u32 nfs4_fl_calc_ds_index(struct pnfs_layout_segment *lseg, u32 j);
109struct nfs4_pnfs_ds *nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg,
110 u32 ds_idx);
111
112extern struct nfs4_file_layout_dsaddr *
113nfs4_fl_alloc_deviceid_node(struct nfs_server *server,
114 struct pnfs_device *pdev, gfp_t gfp_flags);
115extern void nfs4_fl_put_deviceid(struct nfs4_file_layout_dsaddr *dsaddr);
116extern void nfs4_fl_free_deviceid(struct nfs4_file_layout_dsaddr *dsaddr);
117
118#endif /* FS_NFS_NFS4FILELAYOUT_H */
119

source code of linux/fs/nfs/filelayout/filelayout.h