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author | codeworkx <daniel.hillenbrand@codeworkx.de> | 2012-06-02 13:09:29 +0200 |
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committer | codeworkx <daniel.hillenbrand@codeworkx.de> | 2012-06-02 13:09:29 +0200 |
commit | c6da2cfeb05178a11c6d062a06f8078150ee492f (patch) | |
tree | f3b4021d252c52d6463a9b3c1bb7245e399b009c /fs/fat/inode.c | |
parent | c6d7c4dbff353eac7919342ae6b3299a378160a6 (diff) | |
download | kernel_samsung_smdk4412-c6da2cfeb05178a11c6d062a06f8078150ee492f.zip kernel_samsung_smdk4412-c6da2cfeb05178a11c6d062a06f8078150ee492f.tar.gz kernel_samsung_smdk4412-c6da2cfeb05178a11c6d062a06f8078150ee492f.tar.bz2 |
samsung update 1
Diffstat (limited to 'fs/fat/inode.c')
-rw-r--r-- | fs/fat/inode.c | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/fs/fat/inode.c b/fs/fat/inode.c index cb8d839..d7136bd 100644 --- a/fs/fat/inode.c +++ b/fs/fat/inode.c @@ -242,6 +242,71 @@ static const struct address_space_operations fat_aops = { .bmap = _fat_bmap }; +int _fat_fallocate(struct inode *inode, loff_t len) +{ + struct super_block *sb = inode->i_sb; + struct msdos_sb_info *sbi = MSDOS_SB(sb); + int err; + sector_t nblocks, iblock; + unsigned short offset; + + if (!S_ISREG(inode->i_mode)) { + printk(KERN_ERR "_fat_fallocate: supported only for regular files\n"); + return -EOPNOTSUPP; + } + + if (IS_IMMUTABLE(inode)) { + return -EPERM; + } + + mutex_lock(&inode->i_mutex); + + /* file is already big enough */ + if (len <= i_size_read(inode)) { + mutex_unlock(&inode->i_mutex); + return 0; + } + + nblocks = (len + sb->s_blocksize - 1 ) >> sb->s_blocksize_bits; + iblock = (MSDOS_I(inode)->mmu_private + sb->s_blocksize - 1) >> sb->s_blocksize_bits; + + /* validate new size */ + err = inode_newsize_ok(inode, len); + if (err) { + mutex_unlock(&inode->i_mutex); + return err; + } + + /* check for available blocks on last cluster */ + offset = (unsigned long)iblock & (sbi->sec_per_clus - 1); + if (offset) { + iblock += min((unsigned long) (sbi->sec_per_clus - offset), + (unsigned long) (nblocks - iblock)); + } + + /* now allocate new clusters */ + while (iblock < nblocks) { + err = fat_add_cluster(inode); + if (err) { + break; + } + + iblock += min((unsigned long) sbi->sec_per_clus, + (unsigned long) (nblocks - iblock)); + } + + /* update inode informations */ + len = min(len, (loff_t)(iblock << sb->s_blocksize_bits)); + i_size_write(inode, len); + MSDOS_I(inode)->mmu_private = len; + inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC; + mark_inode_dirty(inode); + + mutex_unlock(&inode->i_mutex); + + return err; +} + /* * New FAT inode stuff. We do the following: * a) i_ino is constant and has nothing with on-disk location. @@ -1245,6 +1310,7 @@ int fat_fill_super(struct super_block *sb, void *data, int silent, int isvfat, struct inode *root_inode = NULL, *fat_inode = NULL; struct buffer_head *bh; struct fat_boot_sector *b; + struct fat_boot_bsx *bsx; struct msdos_sb_info *sbi; u16 logical_sector_size; u32 total_sectors, total_clusters, fat_clusters, rootdir_sectors; @@ -1390,6 +1456,8 @@ int fat_fill_super(struct super_block *sb, void *data, int silent, int isvfat, goto out_fail; } + bsx = (struct fat_boot_bsx *)(bh->b_data + FAT32_BSX_OFFSET); + fsinfo = (struct fat_boot_fsinfo *)fsinfo_bh->b_data; if (!IS_FSINFO(fsinfo)) { fat_msg(sb, KERN_WARNING, "Invalid FSINFO signature: " @@ -1405,8 +1473,14 @@ int fat_fill_super(struct super_block *sb, void *data, int silent, int isvfat, } brelse(fsinfo_bh); + } else { + bsx = (struct fat_boot_bsx *)(bh->b_data + FAT16_BSX_OFFSET); } + /* interpret volume ID as a little endian 32 bit integer */ + sbi->vol_id = (((u32)bsx->vol_id[0]) | ((u32)bsx->vol_id[1] << 8) | + ((u32)bsx->vol_id[2] << 16) | ((u32)bsx->vol_id[3] << 24)); + sbi->dir_per_block = sb->s_blocksize / sizeof(struct msdos_dir_entry); sbi->dir_per_block_bits = ffs(sbi->dir_per_block) - 1; |