release/src-rt/linux/linux-2.6/fs/exfat/exfat_blkdev.c

   1 /*
   2  *  Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
   3  *
   4  *  This program is free software; you can redistribute it and/or
   5  *  modify it under the terms of the GNU General Public License
   6  *  as published by the Free Software Foundation; either version 2
   7  *  of the License, or (at your option) any later version.
   8  *
   9  *  This program is distributed in the hope that it will 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 to the Free Software
  16  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  17  */
  18
  19 /************************************************************************/
  20 /*                                                                      */
  21 /*  PROJECT : exFAT & FAT12/16/32 File System                           */
  22 /*  FILE    : exfat_blkdev.c                                            */
  23 /*  PURPOSE : exFAT Block Device Driver Glue Layer                      */
  24 /*                                                                      */
  25 /*----------------------------------------------------------------------*/
  26 /*  NOTES                                                               */
  27 /*                                                                      */
  28 /*----------------------------------------------------------------------*/
  29 /*  REVISION HISTORY (Ver 0.9)                                          */
  30 /*                                                                      */
  31 /*  - 2010.11.15 [Joosun Hahn] : first writing                          */
  32 /*                                                                      */
  33 /************************************************************************/
  34
  35 #include <linux/blkdev.h>
  36
  37 #include "exfat_config.h"
  38 #include "exfat_global.h"
  39 #include "exfat_blkdev.h"
  40 #include "exfat_data.h"
  41 #include "exfat_api.h"
  42 #include "exfat_super.h"
  43
  44 /*----------------------------------------------------------------------*/
  45 /*  Constant & Macro Definitions                                        */
  46 /*----------------------------------------------------------------------*/
  47
  48 /*----------------------------------------------------------------------*/
  49 /*  Global Variable Definitions                                         */
  50 /*----------------------------------------------------------------------*/
  51
  52 /*----------------------------------------------------------------------*/
  53 /*  Local Variable Definitions                                          */
  54 /*----------------------------------------------------------------------*/
  55
  56 /*======================================================================*/
  57 /*  Function Definitions                                                */
  58 /*======================================================================*/
  59
  60 INT32 bdev_init(void)
  61 {
  62         return(FFS_SUCCESS);
  63 }
  64
  65 INT32 bdev_shutdown(void)
  66 {
  67         return(FFS_SUCCESS);
  68 }
  69
  70 INT32 bdev_open(struct super_block *sb)
  71 {
  72         BD_INFO_T *p_bd = &(EXFAT_SB(sb)->bd_info);
  73
  74         if (p_bd->opened) return(FFS_SUCCESS);
  75
  76         p_bd->sector_size      = bdev_logical_block_size(sb->s_bdev);
  77         p_bd->sector_size_bits = my_log2(p_bd->sector_size);
  78         p_bd->sector_size_mask = p_bd->sector_size - 1;
  79         p_bd->num_sectors      = i_size_read(sb->s_bdev->bd_inode) >> p_bd->sector_size_bits;
  80
  81         p_bd->opened = TRUE;
  82
  83         return(FFS_SUCCESS);
  84 }
  85
  86 INT32 bdev_close(struct super_block *sb)
  87 {
  88         BD_INFO_T *p_bd = &(EXFAT_SB(sb)->bd_info);
  89
  90         if (!p_bd->opened) return(FFS_SUCCESS);
  91
  92         p_bd->opened = FALSE;
  93         return(FFS_SUCCESS);
  94 }
  95
  96 INT32 bdev_read(struct super_block *sb, UINT32 secno, struct buffer_head **bh, UINT32 num_secs, INT32 read)
  97 {
  98         BD_INFO_T *p_bd = &(EXFAT_SB(sb)->bd_info);
  99         FS_INFO_T *p_fs = &(EXFAT_SB(sb)->fs_info);
 100 #if EXFAT_CONFIG_KERNEL_DEBUG
 101         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 102         long flags = sbi->debug_flags;
 103
 104         if (flags & EXFAT_DEBUGFLAGS_ERROR_RW)  return (FFS_MEDIAERR);
 105 #endif /* EXFAT_CONFIG_KERNEL_DEBUG */
 106
 107         if (!p_bd->opened) return(FFS_MEDIAERR);
 108
 109         if (*bh) __brelse(*bh);
 110
 111         if (read)
 112                 *bh = __bread(sb->s_bdev, secno, num_secs << p_bd->sector_size_bits);
 113         else
 114                 *bh = __getblk(sb->s_bdev, secno, num_secs << p_bd->sector_size_bits);
 115
 116         if (*bh) return(FFS_SUCCESS);
 117
 118         WARN(!p_fs->dev_ejected,
 119                 "[EXFAT] No bh, device seems wrong or to be ejected.\n");
 120
 121         return(FFS_MEDIAERR);
 122 }
 123
 124 INT32 bdev_write(struct super_block *sb, UINT32 secno, struct buffer_head *bh, UINT32 num_secs, INT32 sync)
 125 {
 126         INT32 count;
 127         struct buffer_head *bh2;
 128         BD_INFO_T *p_bd = &(EXFAT_SB(sb)->bd_info);
 129         FS_INFO_T *p_fs = &(EXFAT_SB(sb)->fs_info);
 130 #if EXFAT_CONFIG_KERNEL_DEBUG
 131         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 132         long flags = sbi->debug_flags;
 133
 134         if (flags & EXFAT_DEBUGFLAGS_ERROR_RW)  return (FFS_MEDIAERR);
 135 #endif /* EXFAT_CONFIG_KERNEL_DEBUG */
 136
 137         if (!p_bd->opened) return(FFS_MEDIAERR);
 138
 139         if (secno == bh->b_blocknr) {
 140                 lock_buffer(bh);
 141                 set_buffer_uptodate(bh);
 142                 mark_buffer_dirty(bh);
 143                 unlock_buffer(bh);
 144                 if (sync && (sync_dirty_buffer(bh) != 0))
 145                         return (FFS_MEDIAERR);
 146         } else {
 147                 count = num_secs << p_bd->sector_size_bits;
 148
 149                 bh2 = __getblk(sb->s_bdev, secno, count);
 150
 151                 if (bh2 == NULL)
 152                         goto no_bh;
 153
 154                 lock_buffer(bh2);
 155                 MEMCPY(bh2->b_data, bh->b_data, count);
 156                 set_buffer_uptodate(bh2);
 157                 mark_buffer_dirty(bh2);
 158                 unlock_buffer(bh2);
 159                 if (sync && (sync_dirty_buffer(bh2) != 0)) {
 160                         __brelse(bh2);
 161                         goto no_bh;
 162                 }
 163                 __brelse(bh2);
 164         }
 165
 166         return(FFS_SUCCESS);
 167
 168 no_bh:
 169         WARN(!p_fs->dev_ejected,
 170                 "[EXFAT] No bh, device seems wrong or to be ejected.\n");
 171
 172         return (FFS_MEDIAERR);
 173 }
 174
 175 INT32 bdev_sync(struct super_block *sb)
 176 {
 177         BD_INFO_T *p_bd = &(EXFAT_SB(sb)->bd_info);
 178 #if EXFAT_CONFIG_KERNEL_DEBUG
 179         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 180         long flags = sbi->debug_flags;
 181
 182         if (flags & EXFAT_DEBUGFLAGS_ERROR_RW)  return (FFS_MEDIAERR);
 183 #endif /* EXFAT_CONFIG_KERNEL_DEBUG */
 184
 185         if (!p_bd->opened) return(FFS_MEDIAERR);
 186
 187         return sync_blockdev(sb->s_bdev);
 188 }
 189
 190 /* end of exfat_blkdev.c */