diff options
Diffstat (limited to 'drivers/staging/exfat/exfat_blkdev.c')
| -rw-r--r-- | drivers/staging/exfat/exfat_blkdev.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/drivers/staging/exfat/exfat_blkdev.c b/drivers/staging/exfat/exfat_blkdev.c new file mode 100644 index 000000000000..f086c75e7076 --- /dev/null +++ b/drivers/staging/exfat/exfat_blkdev.c @@ -0,0 +1,136 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd. + */ + +#include <linux/blkdev.h> +#include <linux/buffer_head.h> +#include <linux/fs.h> +#include "exfat.h" + +void bdev_open(struct super_block *sb) +{ + struct bd_info_t *p_bd = &(EXFAT_SB(sb)->bd_info); + + if (p_bd->opened) + return; + + p_bd->sector_size = bdev_logical_block_size(sb->s_bdev); + p_bd->sector_size_bits = ilog2(p_bd->sector_size); + p_bd->sector_size_mask = p_bd->sector_size - 1; + p_bd->num_sectors = i_size_read(sb->s_bdev->bd_inode) >> + p_bd->sector_size_bits; + p_bd->opened = true; +} + +void bdev_close(struct super_block *sb) +{ + struct bd_info_t *p_bd = &(EXFAT_SB(sb)->bd_info); + + p_bd->opened = false; +} + +int bdev_read(struct super_block *sb, sector_t secno, struct buffer_head **bh, + u32 num_secs, bool read) +{ + struct bd_info_t *p_bd = &(EXFAT_SB(sb)->bd_info); + struct fs_info_t *p_fs = &(EXFAT_SB(sb)->fs_info); +#ifdef CONFIG_EXFAT_KERNEL_DEBUG + struct exfat_sb_info *sbi = EXFAT_SB(sb); + long flags = sbi->debug_flags; + + if (flags & EXFAT_DEBUGFLAGS_ERROR_RW) + return FFS_MEDIAERR; +#endif /* CONFIG_EXFAT_KERNEL_DEBUG */ + + if (!p_bd->opened) + return FFS_MEDIAERR; + + if (*bh) + __brelse(*bh); + + if (read) + *bh = __bread(sb->s_bdev, secno, + num_secs << p_bd->sector_size_bits); + else + *bh = __getblk(sb->s_bdev, secno, + num_secs << p_bd->sector_size_bits); + + if (*bh) + return 0; + + WARN(!p_fs->dev_ejected, + "[EXFAT] No bh, device seems wrong or to be ejected.\n"); + + return FFS_MEDIAERR; +} + +int bdev_write(struct super_block *sb, sector_t secno, struct buffer_head *bh, + u32 num_secs, bool sync) +{ + s32 count; + struct buffer_head *bh2; + struct bd_info_t *p_bd = &(EXFAT_SB(sb)->bd_info); + struct fs_info_t *p_fs = &(EXFAT_SB(sb)->fs_info); +#ifdef CONFIG_EXFAT_KERNEL_DEBUG + struct exfat_sb_info *sbi = EXFAT_SB(sb); + long flags = sbi->debug_flags; + + if (flags & EXFAT_DEBUGFLAGS_ERROR_RW) + return FFS_MEDIAERR; +#endif /* CONFIG_EXFAT_KERNEL_DEBUG */ + + if (!p_bd->opened) + return FFS_MEDIAERR; + + if (secno == bh->b_blocknr) { + lock_buffer(bh); + set_buffer_uptodate(bh); + mark_buffer_dirty(bh); + unlock_buffer(bh); + if (sync && (sync_dirty_buffer(bh) != 0)) + return FFS_MEDIAERR; + } else { + count = num_secs << p_bd->sector_size_bits; + + bh2 = __getblk(sb->s_bdev, secno, count); + if (!bh2) + goto no_bh; + + lock_buffer(bh2); + memcpy(bh2->b_data, bh->b_data, count); + set_buffer_uptodate(bh2); + mark_buffer_dirty(bh2); + unlock_buffer(bh2); + if (sync && (sync_dirty_buffer(bh2) != 0)) { + __brelse(bh2); + goto no_bh; + } + __brelse(bh2); + } + + return 0; + +no_bh: + WARN(!p_fs->dev_ejected, + "[EXFAT] No bh, device seems wrong or to be ejected.\n"); + + return FFS_MEDIAERR; +} + +int bdev_sync(struct super_block *sb) +{ + struct bd_info_t *p_bd = &(EXFAT_SB(sb)->bd_info); +#ifdef CONFIG_EXFAT_KERNEL_DEBUG + struct exfat_sb_info *sbi = EXFAT_SB(sb); + long flags = sbi->debug_flags; + + if (flags & EXFAT_DEBUGFLAGS_ERROR_RW) + return FFS_MEDIAERR; +#endif /* CONFIG_EXFAT_KERNEL_DEBUG */ + + if (!p_bd->opened) + return FFS_MEDIAERR; + + return sync_blockdev(sb->s_bdev); +} |