fs/nfs/filelayout/filelayout.h

   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
  44 enum stripetype4 {
  45         STRIPE_SPARSE = 1,
  46         STRIPE_DENSE = 2
  47 };
  48
  49 struct 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[1];
  55 };
  56
  57 struct 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_file_layout_dsaddr *dsaddr; /* Point to GETDEVINFO data */
  65         unsigned int num_fh;
  66         struct nfs_fh **fh_array;
  67 };
  68
  69 struct nfs4_filelayout {
  70         struct pnfs_layout_hdr generic_hdr;
  71         struct pnfs_ds_commit_info commit_info;
  72 };
  73
  74 static inline struct nfs4_filelayout *
  75 FILELAYOUT_FROM_HDR(struct pnfs_layout_hdr *lo)
  76 {
  77         return container_of(lo, struct nfs4_filelayout, generic_hdr);
  78 }
  79
  80 static inline struct nfs4_filelayout_segment *
  81 FILELAYOUT_LSEG(struct pnfs_layout_segment *lseg)
  82 {
  83         return container_of(lseg,
  84                             struct nfs4_filelayout_segment,
  85                             generic_hdr);
  86 }
  87
  88 static inline struct nfs4_deviceid_node *
  89 FILELAYOUT_DEVID_NODE(struct pnfs_layout_segment *lseg)
  90 {
  91         return &FILELAYOUT_LSEG(lseg)->dsaddr->id_node;
  92 }
  93
  94 static inline bool
  95 filelayout_test_devid_invalid(struct nfs4_deviceid_node *node)
  96 {
  97         return test_bit(NFS_DEVICEID_INVALID, &node->flags);
  98 }
  99
 100 extern bool
 101 filelayout_test_devid_unavailable(struct nfs4_deviceid_node *node);
 102
 103 extern struct nfs_fh *
 104 nfs4_fl_select_ds_fh(struct pnfs_layout_segment *lseg, u32 j);
 105
 106 u32 nfs4_fl_calc_j_index(struct pnfs_layout_segment *lseg, loff_t offset);
 107 u32 nfs4_fl_calc_ds_index(struct pnfs_layout_segment *lseg, u32 j);
 108 struct nfs4_pnfs_ds *nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg,
 109                                         u32 ds_idx);
 110
 111 extern struct nfs4_file_layout_dsaddr *
 112 nfs4_fl_alloc_deviceid_node(struct nfs_server *server,
 113         struct pnfs_device *pdev, gfp_t gfp_flags);
 114 extern void nfs4_fl_put_deviceid(struct nfs4_file_layout_dsaddr *dsaddr);
 115 extern void nfs4_fl_free_deviceid(struct nfs4_file_layout_dsaddr *dsaddr);
 116
 117 #endif /* FS_NFS_NFS4FILELAYOUT_H */