copy/xfs_copy.h

   1 /*
   2  * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
   3  * All Rights Reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it would be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write the Free Software Foundation,
  16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17  */
  18
  19 /*
  20  * An on-disk allocation group header is composed of 4 structures,
  21  * each of which is 1 disk sector long where the sector size is at
  22  * least 512 bytes long (BBSIZE).
  23  *
  24  * There's one ag_header per ag and the superblock in the first ag
  25  * is the contains the real data for the entire filesystem (although
  26  * most of the relevant data won't change anyway even on a growfs).
  27  *
  28  * The filesystem superblock specifies the number of AG's and
  29  * the AG size.  That splits the filesystem up into N pieces,
  30  * each of which is an AG and has an ag_header at the beginning.
  31  */
  32 typedef struct ag_header  {
  33         xfs_dsb_t       *xfs_sb;        /* superblock for filesystem or AG */
  34         xfs_agf_t       *xfs_agf;       /* free space info */
  35         xfs_agi_t       *xfs_agi;       /* free inode info */
  36         xfs_agfl_t      *xfs_agfl;      /* AG freelist */
  37         char            *residue;
  38         int             residue_length;
  39 } ag_header_t;
  40
  41 /*
  42  * The position/buf_position, length/buf_length, data/buffer pairs
  43  * exist because of alignment constraints for direct I/O and dealing
  44  * with scenarios where either the source or target or both is a file
  45  * and the blocksize of the filesystem where file resides is different
  46  * from that of the filesystem image being duplicated.  You can get
  47  * alignment problems resulting from things like AG's starting on
  48  * non-aligned points in the filesystem.  So you have to be able
  49  * to read from points "before" the requested starting point and
  50  * read in more data than requested.
  51  */
  52 struct t_args;
  53 typedef struct {
  54         int             id;             /* buffer ID */
  55         size_t          size;           /* size of buffer -- fixed */
  56         size_t          min_io_size;    /* for direct I/O */
  57         int             data_align;     /* data buffer alignment */
  58         xfs_off_t       position;       /* requested position (bytes) */
  59         size_t          length;         /* requested length (bytes) */
  60         char            *data;          /* pointer to data buffer */
  61         struct t_args   *owner;         /* for non-parallel writes */
  62 } wbuf;
  63
  64 typedef struct t_args {
  65         int             id;
  66         uuid_t          uuid;
  67         pthread_mutex_t wait;
  68         int             fd;
  69 } thread_args;
  70
  71 typedef struct {
  72         pthread_mutex_t mutex;
  73         int             num_working;
  74         wbuf            *buffer;
  75 } thread_control;
  76
  77 typedef int thread_id;
  78 typedef int tm_index;                   /* index into thread mask array */
  79 typedef uint32_t thread_mask;           /* a thread mask */
  80
  81 typedef struct {
  82         char            *name;
  83         int             fd;
  84         xfs_off_t       position;
  85         pthread_t       pid;
  86         int             state;
  87         int             error;
  88         int             err_type;
  89 } target_control;