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1981 lines
51 KiB
1981 lines
51 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* linux/fs/fat/inode.c |
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* |
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* Written 1992,1993 by Werner Almesberger |
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* VFAT extensions by Gordon Chaffee, merged with msdos fs by Henrik Storner |
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* Rewritten for the constant inumbers support by Al Viro |
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* |
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* Fixes: |
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* |
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* Max Cohan: Fixed invalid FSINFO offset when info_sector is 0 |
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*/ |
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|
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#include <linux/module.h> |
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#include <linux/pagemap.h> |
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#include <linux/mpage.h> |
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#include <linux/vfs.h> |
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#include <linux/seq_file.h> |
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#include <linux/parser.h> |
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#include <linux/uio.h> |
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#include <linux/blkdev.h> |
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#include <linux/backing-dev.h> |
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#include <asm/unaligned.h> |
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#include <linux/random.h> |
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#include <linux/iversion.h> |
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#include "fat.h" |
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|
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#ifndef CONFIG_FAT_DEFAULT_IOCHARSET |
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/* if user don't select VFAT, this is undefined. */ |
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#define CONFIG_FAT_DEFAULT_IOCHARSET "" |
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#endif |
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#define KB_IN_SECTORS 2 |
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|
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/* DOS dates from 1980/1/1 through 2107/12/31 */ |
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#define FAT_DATE_MIN (0<<9 | 1<<5 | 1) |
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#define FAT_DATE_MAX (127<<9 | 12<<5 | 31) |
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#define FAT_TIME_MAX (23<<11 | 59<<5 | 29) |
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|
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/* |
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* A deserialized copy of the on-disk structure laid out in struct |
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* fat_boot_sector. |
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*/ |
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struct fat_bios_param_block { |
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u16 fat_sector_size; |
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u8 fat_sec_per_clus; |
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u16 fat_reserved; |
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u8 fat_fats; |
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u16 fat_dir_entries; |
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u16 fat_sectors; |
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u16 fat_fat_length; |
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u32 fat_total_sect; |
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|
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u8 fat16_state; |
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u32 fat16_vol_id; |
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u32 fat32_length; |
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u32 fat32_root_cluster; |
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u16 fat32_info_sector; |
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u8 fat32_state; |
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u32 fat32_vol_id; |
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}; |
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static int fat_default_codepage = CONFIG_FAT_DEFAULT_CODEPAGE; |
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static char fat_default_iocharset[] = CONFIG_FAT_DEFAULT_IOCHARSET; |
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static struct fat_floppy_defaults { |
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unsigned nr_sectors; |
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unsigned sec_per_clus; |
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unsigned dir_entries; |
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unsigned media; |
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unsigned fat_length; |
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} floppy_defaults[] = { |
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{ |
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.nr_sectors = 160 * KB_IN_SECTORS, |
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.sec_per_clus = 1, |
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.dir_entries = 64, |
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.media = 0xFE, |
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.fat_length = 1, |
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}, |
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{ |
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.nr_sectors = 180 * KB_IN_SECTORS, |
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.sec_per_clus = 1, |
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.dir_entries = 64, |
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.media = 0xFC, |
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.fat_length = 2, |
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}, |
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{ |
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.nr_sectors = 320 * KB_IN_SECTORS, |
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.sec_per_clus = 2, |
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.dir_entries = 112, |
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.media = 0xFF, |
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.fat_length = 1, |
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}, |
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{ |
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.nr_sectors = 360 * KB_IN_SECTORS, |
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.sec_per_clus = 2, |
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.dir_entries = 112, |
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.media = 0xFD, |
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.fat_length = 2, |
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}, |
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}; |
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|
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int fat_add_cluster(struct inode *inode) |
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{ |
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int err, cluster; |
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|
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err = fat_alloc_clusters(inode, &cluster, 1); |
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if (err) |
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return err; |
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/* FIXME: this cluster should be added after data of this |
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* cluster is writed */ |
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err = fat_chain_add(inode, cluster, 1); |
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if (err) |
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fat_free_clusters(inode, cluster); |
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return err; |
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} |
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static inline int __fat_get_block(struct inode *inode, sector_t iblock, |
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unsigned long *max_blocks, |
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struct buffer_head *bh_result, int create) |
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{ |
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struct super_block *sb = inode->i_sb; |
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struct msdos_sb_info *sbi = MSDOS_SB(sb); |
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unsigned long mapped_blocks; |
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sector_t phys, last_block; |
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int err, offset; |
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err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create, false); |
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if (err) |
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return err; |
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if (phys) { |
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map_bh(bh_result, sb, phys); |
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*max_blocks = min(mapped_blocks, *max_blocks); |
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return 0; |
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} |
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if (!create) |
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return 0; |
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if (iblock != MSDOS_I(inode)->mmu_private >> sb->s_blocksize_bits) { |
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fat_fs_error(sb, "corrupted file size (i_pos %lld, %lld)", |
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MSDOS_I(inode)->i_pos, MSDOS_I(inode)->mmu_private); |
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return -EIO; |
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} |
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last_block = inode->i_blocks >> (sb->s_blocksize_bits - 9); |
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offset = (unsigned long)iblock & (sbi->sec_per_clus - 1); |
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/* |
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* allocate a cluster according to the following. |
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* 1) no more available blocks |
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* 2) not part of fallocate region |
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*/ |
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if (!offset && !(iblock < last_block)) { |
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/* TODO: multiple cluster allocation would be desirable. */ |
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err = fat_add_cluster(inode); |
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if (err) |
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return err; |
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} |
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/* available blocks on this cluster */ |
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mapped_blocks = sbi->sec_per_clus - offset; |
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|
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*max_blocks = min(mapped_blocks, *max_blocks); |
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MSDOS_I(inode)->mmu_private += *max_blocks << sb->s_blocksize_bits; |
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err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create, false); |
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if (err) |
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return err; |
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if (!phys) { |
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fat_fs_error(sb, |
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"invalid FAT chain (i_pos %lld, last_block %llu)", |
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MSDOS_I(inode)->i_pos, |
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(unsigned long long)last_block); |
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return -EIO; |
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} |
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BUG_ON(*max_blocks != mapped_blocks); |
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set_buffer_new(bh_result); |
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map_bh(bh_result, sb, phys); |
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return 0; |
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} |
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static int fat_get_block(struct inode *inode, sector_t iblock, |
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struct buffer_head *bh_result, int create) |
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{ |
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struct super_block *sb = inode->i_sb; |
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unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits; |
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int err; |
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err = __fat_get_block(inode, iblock, &max_blocks, bh_result, create); |
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if (err) |
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return err; |
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bh_result->b_size = max_blocks << sb->s_blocksize_bits; |
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return 0; |
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} |
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static int fat_writepage(struct page *page, struct writeback_control *wbc) |
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{ |
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return block_write_full_page(page, fat_get_block, wbc); |
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} |
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static int fat_writepages(struct address_space *mapping, |
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struct writeback_control *wbc) |
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{ |
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return mpage_writepages(mapping, wbc, fat_get_block); |
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} |
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static int fat_readpage(struct file *file, struct page *page) |
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{ |
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return mpage_readpage(page, fat_get_block); |
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} |
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static void fat_readahead(struct readahead_control *rac) |
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{ |
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mpage_readahead(rac, fat_get_block); |
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} |
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static void fat_write_failed(struct address_space *mapping, loff_t to) |
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{ |
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struct inode *inode = mapping->host; |
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if (to > inode->i_size) { |
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truncate_pagecache(inode, inode->i_size); |
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fat_truncate_blocks(inode, inode->i_size); |
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} |
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} |
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static int fat_write_begin(struct file *file, struct address_space *mapping, |
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loff_t pos, unsigned len, unsigned flags, |
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struct page **pagep, void **fsdata) |
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{ |
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int err; |
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*pagep = NULL; |
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err = cont_write_begin(file, mapping, pos, len, flags, |
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pagep, fsdata, fat_get_block, |
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&MSDOS_I(mapping->host)->mmu_private); |
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if (err < 0) |
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fat_write_failed(mapping, pos + len); |
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return err; |
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} |
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static int fat_write_end(struct file *file, struct address_space *mapping, |
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loff_t pos, unsigned len, unsigned copied, |
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struct page *pagep, void *fsdata) |
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{ |
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struct inode *inode = mapping->host; |
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int err; |
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err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata); |
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if (err < len) |
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fat_write_failed(mapping, pos + len); |
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if (!(err < 0) && !(MSDOS_I(inode)->i_attrs & ATTR_ARCH)) { |
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fat_truncate_time(inode, NULL, S_CTIME|S_MTIME); |
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MSDOS_I(inode)->i_attrs |= ATTR_ARCH; |
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mark_inode_dirty(inode); |
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} |
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return err; |
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} |
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static ssize_t fat_direct_IO(struct kiocb *iocb, struct iov_iter *iter) |
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{ |
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struct file *file = iocb->ki_filp; |
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struct address_space *mapping = file->f_mapping; |
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struct inode *inode = mapping->host; |
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size_t count = iov_iter_count(iter); |
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loff_t offset = iocb->ki_pos; |
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ssize_t ret; |
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if (iov_iter_rw(iter) == WRITE) { |
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/* |
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* FIXME: blockdev_direct_IO() doesn't use ->write_begin(), |
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* so we need to update the ->mmu_private to block boundary. |
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* |
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* But we must fill the remaining area or hole by nul for |
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* updating ->mmu_private. |
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* |
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* Return 0, and fallback to normal buffered write. |
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*/ |
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loff_t size = offset + count; |
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if (MSDOS_I(inode)->mmu_private < size) |
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return 0; |
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} |
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/* |
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* FAT need to use the DIO_LOCKING for avoiding the race |
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* condition of fat_get_block() and ->truncate(). |
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*/ |
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ret = blockdev_direct_IO(iocb, inode, iter, fat_get_block); |
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if (ret < 0 && iov_iter_rw(iter) == WRITE) |
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fat_write_failed(mapping, offset + count); |
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return ret; |
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} |
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static int fat_get_block_bmap(struct inode *inode, sector_t iblock, |
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struct buffer_head *bh_result, int create) |
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{ |
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struct super_block *sb = inode->i_sb; |
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unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits; |
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int err; |
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sector_t bmap; |
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unsigned long mapped_blocks; |
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BUG_ON(create != 0); |
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err = fat_bmap(inode, iblock, &bmap, &mapped_blocks, create, true); |
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if (err) |
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return err; |
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if (bmap) { |
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map_bh(bh_result, sb, bmap); |
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max_blocks = min(mapped_blocks, max_blocks); |
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} |
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bh_result->b_size = max_blocks << sb->s_blocksize_bits; |
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return 0; |
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} |
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static sector_t _fat_bmap(struct address_space *mapping, sector_t block) |
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{ |
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sector_t blocknr; |
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/* fat_get_cluster() assumes the requested blocknr isn't truncated. */ |
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down_read(&MSDOS_I(mapping->host)->truncate_lock); |
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blocknr = generic_block_bmap(mapping, block, fat_get_block_bmap); |
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up_read(&MSDOS_I(mapping->host)->truncate_lock); |
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return blocknr; |
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} |
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/* |
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* fat_block_truncate_page() zeroes out a mapping from file offset `from' |
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* up to the end of the block which corresponds to `from'. |
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* This is required during truncate to physically zeroout the tail end |
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* of that block so it doesn't yield old data if the file is later grown. |
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* Also, avoid causing failure from fsx for cases of "data past EOF" |
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*/ |
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int fat_block_truncate_page(struct inode *inode, loff_t from) |
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{ |
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return block_truncate_page(inode->i_mapping, from, fat_get_block); |
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} |
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static const struct address_space_operations fat_aops = { |
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.readpage = fat_readpage, |
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.readahead = fat_readahead, |
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.writepage = fat_writepage, |
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.writepages = fat_writepages, |
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.write_begin = fat_write_begin, |
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.write_end = fat_write_end, |
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.direct_IO = fat_direct_IO, |
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.bmap = _fat_bmap |
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}; |
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/* |
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* New FAT inode stuff. We do the following: |
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* a) i_ino is constant and has nothing with on-disk location. |
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* b) FAT manages its own cache of directory entries. |
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* c) *This* cache is indexed by on-disk location. |
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* d) inode has an associated directory entry, all right, but |
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* it may be unhashed. |
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* e) currently entries are stored within struct inode. That should |
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* change. |
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* f) we deal with races in the following way: |
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* 1. readdir() and lookup() do FAT-dir-cache lookup. |
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* 2. rename() unhashes the F-d-c entry and rehashes it in |
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* a new place. |
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* 3. unlink() and rmdir() unhash F-d-c entry. |
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* 4. fat_write_inode() checks whether the thing is unhashed. |
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* If it is we silently return. If it isn't we do bread(), |
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* check if the location is still valid and retry if it |
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* isn't. Otherwise we do changes. |
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* 5. Spinlock is used to protect hash/unhash/location check/lookup |
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* 6. fat_evict_inode() unhashes the F-d-c entry. |
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* 7. lookup() and readdir() do igrab() if they find a F-d-c entry |
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* and consider negative result as cache miss. |
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*/ |
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static void fat_hash_init(struct super_block *sb) |
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{ |
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struct msdos_sb_info *sbi = MSDOS_SB(sb); |
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int i; |
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spin_lock_init(&sbi->inode_hash_lock); |
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for (i = 0; i < FAT_HASH_SIZE; i++) |
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INIT_HLIST_HEAD(&sbi->inode_hashtable[i]); |
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} |
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static inline unsigned long fat_hash(loff_t i_pos) |
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{ |
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return hash_32(i_pos, FAT_HASH_BITS); |
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} |
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static void dir_hash_init(struct super_block *sb) |
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{ |
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struct msdos_sb_info *sbi = MSDOS_SB(sb); |
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int i; |
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spin_lock_init(&sbi->dir_hash_lock); |
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for (i = 0; i < FAT_HASH_SIZE; i++) |
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INIT_HLIST_HEAD(&sbi->dir_hashtable[i]); |
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} |
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void fat_attach(struct inode *inode, loff_t i_pos) |
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{ |
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struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); |
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if (inode->i_ino != MSDOS_ROOT_INO) { |
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struct hlist_head *head = sbi->inode_hashtable |
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+ fat_hash(i_pos); |
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spin_lock(&sbi->inode_hash_lock); |
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MSDOS_I(inode)->i_pos = i_pos; |
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hlist_add_head(&MSDOS_I(inode)->i_fat_hash, head); |
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spin_unlock(&sbi->inode_hash_lock); |
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} |
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/* If NFS support is enabled, cache the mapping of start cluster |
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* to directory inode. This is used during reconnection of |
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* dentries to the filesystem root. |
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*/ |
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if (S_ISDIR(inode->i_mode) && sbi->options.nfs) { |
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struct hlist_head *d_head = sbi->dir_hashtable; |
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d_head += fat_dir_hash(MSDOS_I(inode)->i_logstart); |
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spin_lock(&sbi->dir_hash_lock); |
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hlist_add_head(&MSDOS_I(inode)->i_dir_hash, d_head); |
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spin_unlock(&sbi->dir_hash_lock); |
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} |
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} |
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EXPORT_SYMBOL_GPL(fat_attach); |
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void fat_detach(struct inode *inode) |
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{ |
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struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); |
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spin_lock(&sbi->inode_hash_lock); |
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MSDOS_I(inode)->i_pos = 0; |
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hlist_del_init(&MSDOS_I(inode)->i_fat_hash); |
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spin_unlock(&sbi->inode_hash_lock); |
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|
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if (S_ISDIR(inode->i_mode) && sbi->options.nfs) { |
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spin_lock(&sbi->dir_hash_lock); |
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hlist_del_init(&MSDOS_I(inode)->i_dir_hash); |
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spin_unlock(&sbi->dir_hash_lock); |
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} |
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} |
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EXPORT_SYMBOL_GPL(fat_detach); |
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|
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struct inode *fat_iget(struct super_block *sb, loff_t i_pos) |
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{ |
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struct msdos_sb_info *sbi = MSDOS_SB(sb); |
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struct hlist_head *head = sbi->inode_hashtable + fat_hash(i_pos); |
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struct msdos_inode_info *i; |
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struct inode *inode = NULL; |
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|
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spin_lock(&sbi->inode_hash_lock); |
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hlist_for_each_entry(i, head, i_fat_hash) { |
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BUG_ON(i->vfs_inode.i_sb != sb); |
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if (i->i_pos != i_pos) |
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continue; |
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inode = igrab(&i->vfs_inode); |
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if (inode) |
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break; |
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} |
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spin_unlock(&sbi->inode_hash_lock); |
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return inode; |
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} |
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|
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static int is_exec(unsigned char *extension) |
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{ |
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unsigned char exe_extensions[] = "EXECOMBAT", *walk; |
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|
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for (walk = exe_extensions; *walk; walk += 3) |
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if (!strncmp(extension, walk, 3)) |
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return 1; |
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return 0; |
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} |
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static int fat_calc_dir_size(struct inode *inode) |
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{ |
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struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); |
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int ret, fclus, dclus; |
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|
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inode->i_size = 0; |
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if (MSDOS_I(inode)->i_start == 0) |
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return 0; |
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|
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ret = fat_get_cluster(inode, FAT_ENT_EOF, &fclus, &dclus); |
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if (ret < 0) |
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return ret; |
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inode->i_size = (fclus + 1) << sbi->cluster_bits; |
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|
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return 0; |
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} |
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|
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static int fat_validate_dir(struct inode *dir) |
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{ |
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struct super_block *sb = dir->i_sb; |
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|
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if (dir->i_nlink < 2) { |
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/* Directory should have "."/".." entries at least. */ |
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fat_fs_error(sb, "corrupted directory (invalid entries)"); |
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return -EIO; |
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} |
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if (MSDOS_I(dir)->i_start == 0 || |
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MSDOS_I(dir)->i_start == MSDOS_SB(sb)->root_cluster) { |
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/* Directory should point valid cluster. */ |
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fat_fs_error(sb, "corrupted directory (invalid i_start)"); |
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return -EIO; |
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} |
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return 0; |
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} |
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|
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/* doesn't deal with root inode */ |
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int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de) |
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{ |
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struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); |
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int error; |
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|
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MSDOS_I(inode)->i_pos = 0; |
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inode->i_uid = sbi->options.fs_uid; |
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inode->i_gid = sbi->options.fs_gid; |
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inode_inc_iversion(inode); |
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inode->i_generation = prandom_u32(); |
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|
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if ((de->attr & ATTR_DIR) && !IS_FREE(de->name)) { |
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inode->i_generation &= ~1; |
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inode->i_mode = fat_make_mode(sbi, de->attr, S_IRWXUGO); |
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inode->i_op = sbi->dir_ops; |
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inode->i_fop = &fat_dir_operations; |
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|
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MSDOS_I(inode)->i_start = fat_get_start(sbi, de); |
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MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start; |
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error = fat_calc_dir_size(inode); |
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if (error < 0) |
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return error; |
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MSDOS_I(inode)->mmu_private = inode->i_size; |
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|
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set_nlink(inode, fat_subdirs(inode)); |
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|
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error = fat_validate_dir(inode); |
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if (error < 0) |
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return error; |
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} else { /* not a directory */ |
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inode->i_generation |= 1; |
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inode->i_mode = fat_make_mode(sbi, de->attr, |
|
((sbi->options.showexec && !is_exec(de->name + 8)) |
|
? S_IRUGO|S_IWUGO : S_IRWXUGO)); |
|
MSDOS_I(inode)->i_start = fat_get_start(sbi, de); |
|
|
|
MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start; |
|
inode->i_size = le32_to_cpu(de->size); |
|
inode->i_op = &fat_file_inode_operations; |
|
inode->i_fop = &fat_file_operations; |
|
inode->i_mapping->a_ops = &fat_aops; |
|
MSDOS_I(inode)->mmu_private = inode->i_size; |
|
} |
|
if (de->attr & ATTR_SYS) { |
|
if (sbi->options.sys_immutable) |
|
inode->i_flags |= S_IMMUTABLE; |
|
} |
|
fat_save_attrs(inode, de->attr); |
|
|
|
inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1)) |
|
& ~((loff_t)sbi->cluster_size - 1)) >> 9; |
|
|
|
fat_time_fat2unix(sbi, &inode->i_mtime, de->time, de->date, 0); |
|
if (sbi->options.isvfat) { |
|
fat_time_fat2unix(sbi, &inode->i_ctime, de->ctime, |
|
de->cdate, de->ctime_cs); |
|
fat_time_fat2unix(sbi, &inode->i_atime, 0, de->adate, 0); |
|
} else |
|
fat_truncate_time(inode, &inode->i_mtime, S_ATIME|S_CTIME); |
|
|
|
return 0; |
|
} |
|
|
|
static inline void fat_lock_build_inode(struct msdos_sb_info *sbi) |
|
{ |
|
if (sbi->options.nfs == FAT_NFS_NOSTALE_RO) |
|
mutex_lock(&sbi->nfs_build_inode_lock); |
|
} |
|
|
|
static inline void fat_unlock_build_inode(struct msdos_sb_info *sbi) |
|
{ |
|
if (sbi->options.nfs == FAT_NFS_NOSTALE_RO) |
|
mutex_unlock(&sbi->nfs_build_inode_lock); |
|
} |
|
|
|
struct inode *fat_build_inode(struct super_block *sb, |
|
struct msdos_dir_entry *de, loff_t i_pos) |
|
{ |
|
struct inode *inode; |
|
int err; |
|
|
|
fat_lock_build_inode(MSDOS_SB(sb)); |
|
inode = fat_iget(sb, i_pos); |
|
if (inode) |
|
goto out; |
|
inode = new_inode(sb); |
|
if (!inode) { |
|
inode = ERR_PTR(-ENOMEM); |
|
goto out; |
|
} |
|
inode->i_ino = iunique(sb, MSDOS_ROOT_INO); |
|
inode_set_iversion(inode, 1); |
|
err = fat_fill_inode(inode, de); |
|
if (err) { |
|
iput(inode); |
|
inode = ERR_PTR(err); |
|
goto out; |
|
} |
|
fat_attach(inode, i_pos); |
|
insert_inode_hash(inode); |
|
out: |
|
fat_unlock_build_inode(MSDOS_SB(sb)); |
|
return inode; |
|
} |
|
|
|
EXPORT_SYMBOL_GPL(fat_build_inode); |
|
|
|
static int __fat_write_inode(struct inode *inode, int wait); |
|
|
|
static void fat_free_eofblocks(struct inode *inode) |
|
{ |
|
/* Release unwritten fallocated blocks on inode eviction. */ |
|
if ((inode->i_blocks << 9) > |
|
round_up(MSDOS_I(inode)->mmu_private, |
|
MSDOS_SB(inode->i_sb)->cluster_size)) { |
|
int err; |
|
|
|
fat_truncate_blocks(inode, MSDOS_I(inode)->mmu_private); |
|
/* Fallocate results in updating the i_start/iogstart |
|
* for the zero byte file. So, make it return to |
|
* original state during evict and commit it to avoid |
|
* any corruption on the next access to the cluster |
|
* chain for the file. |
|
*/ |
|
err = __fat_write_inode(inode, inode_needs_sync(inode)); |
|
if (err) { |
|
fat_msg(inode->i_sb, KERN_WARNING, "Failed to " |
|
"update on disk inode for unused " |
|
"fallocated blocks, inode could be " |
|
"corrupted. Please run fsck"); |
|
} |
|
|
|
} |
|
} |
|
|
|
static void fat_evict_inode(struct inode *inode) |
|
{ |
|
truncate_inode_pages_final(&inode->i_data); |
|
if (!inode->i_nlink) { |
|
inode->i_size = 0; |
|
fat_truncate_blocks(inode, 0); |
|
} else |
|
fat_free_eofblocks(inode); |
|
|
|
invalidate_inode_buffers(inode); |
|
clear_inode(inode); |
|
fat_cache_inval_inode(inode); |
|
fat_detach(inode); |
|
} |
|
|
|
static void fat_set_state(struct super_block *sb, |
|
unsigned int set, unsigned int force) |
|
{ |
|
struct buffer_head *bh; |
|
struct fat_boot_sector *b; |
|
struct msdos_sb_info *sbi = MSDOS_SB(sb); |
|
|
|
/* do not change any thing if mounted read only */ |
|
if (sb_rdonly(sb) && !force) |
|
return; |
|
|
|
/* do not change state if fs was dirty */ |
|
if (sbi->dirty) { |
|
/* warn only on set (mount). */ |
|
if (set) |
|
fat_msg(sb, KERN_WARNING, "Volume was not properly " |
|
"unmounted. Some data may be corrupt. " |
|
"Please run fsck."); |
|
return; |
|
} |
|
|
|
bh = sb_bread(sb, 0); |
|
if (bh == NULL) { |
|
fat_msg(sb, KERN_ERR, "unable to read boot sector " |
|
"to mark fs as dirty"); |
|
return; |
|
} |
|
|
|
b = (struct fat_boot_sector *) bh->b_data; |
|
|
|
if (is_fat32(sbi)) { |
|
if (set) |
|
b->fat32.state |= FAT_STATE_DIRTY; |
|
else |
|
b->fat32.state &= ~FAT_STATE_DIRTY; |
|
} else /* fat 16 and 12 */ { |
|
if (set) |
|
b->fat16.state |= FAT_STATE_DIRTY; |
|
else |
|
b->fat16.state &= ~FAT_STATE_DIRTY; |
|
} |
|
|
|
mark_buffer_dirty(bh); |
|
sync_dirty_buffer(bh); |
|
brelse(bh); |
|
} |
|
|
|
static void fat_reset_iocharset(struct fat_mount_options *opts) |
|
{ |
|
if (opts->iocharset != fat_default_iocharset) { |
|
/* Note: opts->iocharset can be NULL here */ |
|
kfree(opts->iocharset); |
|
opts->iocharset = fat_default_iocharset; |
|
} |
|
} |
|
|
|
static void delayed_free(struct rcu_head *p) |
|
{ |
|
struct msdos_sb_info *sbi = container_of(p, struct msdos_sb_info, rcu); |
|
unload_nls(sbi->nls_disk); |
|
unload_nls(sbi->nls_io); |
|
fat_reset_iocharset(&sbi->options); |
|
kfree(sbi); |
|
} |
|
|
|
static void fat_put_super(struct super_block *sb) |
|
{ |
|
struct msdos_sb_info *sbi = MSDOS_SB(sb); |
|
|
|
fat_set_state(sb, 0, 0); |
|
|
|
iput(sbi->fsinfo_inode); |
|
iput(sbi->fat_inode); |
|
|
|
call_rcu(&sbi->rcu, delayed_free); |
|
} |
|
|
|
static struct kmem_cache *fat_inode_cachep; |
|
|
|
static struct inode *fat_alloc_inode(struct super_block *sb) |
|
{ |
|
struct msdos_inode_info *ei; |
|
ei = kmem_cache_alloc(fat_inode_cachep, GFP_NOFS); |
|
if (!ei) |
|
return NULL; |
|
|
|
init_rwsem(&ei->truncate_lock); |
|
/* Zeroing to allow iput() even if partial initialized inode. */ |
|
ei->mmu_private = 0; |
|
ei->i_start = 0; |
|
ei->i_logstart = 0; |
|
ei->i_attrs = 0; |
|
ei->i_pos = 0; |
|
|
|
return &ei->vfs_inode; |
|
} |
|
|
|
static void fat_free_inode(struct inode *inode) |
|
{ |
|
kmem_cache_free(fat_inode_cachep, MSDOS_I(inode)); |
|
} |
|
|
|
static void init_once(void *foo) |
|
{ |
|
struct msdos_inode_info *ei = (struct msdos_inode_info *)foo; |
|
|
|
spin_lock_init(&ei->cache_lru_lock); |
|
ei->nr_caches = 0; |
|
ei->cache_valid_id = FAT_CACHE_VALID + 1; |
|
INIT_LIST_HEAD(&ei->cache_lru); |
|
INIT_HLIST_NODE(&ei->i_fat_hash); |
|
INIT_HLIST_NODE(&ei->i_dir_hash); |
|
inode_init_once(&ei->vfs_inode); |
|
} |
|
|
|
static int __init fat_init_inodecache(void) |
|
{ |
|
fat_inode_cachep = kmem_cache_create("fat_inode_cache", |
|
sizeof(struct msdos_inode_info), |
|
0, (SLAB_RECLAIM_ACCOUNT| |
|
SLAB_MEM_SPREAD|SLAB_ACCOUNT), |
|
init_once); |
|
if (fat_inode_cachep == NULL) |
|
return -ENOMEM; |
|
return 0; |
|
} |
|
|
|
static void __exit fat_destroy_inodecache(void) |
|
{ |
|
/* |
|
* Make sure all delayed rcu free inodes are flushed before we |
|
* destroy cache. |
|
*/ |
|
rcu_barrier(); |
|
kmem_cache_destroy(fat_inode_cachep); |
|
} |
|
|
|
static int fat_remount(struct super_block *sb, int *flags, char *data) |
|
{ |
|
bool new_rdonly; |
|
struct msdos_sb_info *sbi = MSDOS_SB(sb); |
|
*flags |= SB_NODIRATIME | (sbi->options.isvfat ? 0 : SB_NOATIME); |
|
|
|
sync_filesystem(sb); |
|
|
|
/* make sure we update state on remount. */ |
|
new_rdonly = *flags & SB_RDONLY; |
|
if (new_rdonly != sb_rdonly(sb)) { |
|
if (new_rdonly) |
|
fat_set_state(sb, 0, 0); |
|
else |
|
fat_set_state(sb, 1, 1); |
|
} |
|
return 0; |
|
} |
|
|
|
static int fat_statfs(struct dentry *dentry, struct kstatfs *buf) |
|
{ |
|
struct super_block *sb = dentry->d_sb; |
|
struct msdos_sb_info *sbi = MSDOS_SB(sb); |
|
u64 id = huge_encode_dev(sb->s_bdev->bd_dev); |
|
|
|
/* If the count of free cluster is still unknown, counts it here. */ |
|
if (sbi->free_clusters == -1 || !sbi->free_clus_valid) { |
|
int err = fat_count_free_clusters(dentry->d_sb); |
|
if (err) |
|
return err; |
|
} |
|
|
|
buf->f_type = dentry->d_sb->s_magic; |
|
buf->f_bsize = sbi->cluster_size; |
|
buf->f_blocks = sbi->max_cluster - FAT_START_ENT; |
|
buf->f_bfree = sbi->free_clusters; |
|
buf->f_bavail = sbi->free_clusters; |
|
buf->f_fsid = u64_to_fsid(id); |
|
buf->f_namelen = |
|
(sbi->options.isvfat ? FAT_LFN_LEN : 12) * NLS_MAX_CHARSET_SIZE; |
|
|
|
return 0; |
|
} |
|
|
|
static int __fat_write_inode(struct inode *inode, int wait) |
|
{ |
|
struct super_block *sb = inode->i_sb; |
|
struct msdos_sb_info *sbi = MSDOS_SB(sb); |
|
struct buffer_head *bh; |
|
struct msdos_dir_entry *raw_entry; |
|
loff_t i_pos; |
|
sector_t blocknr; |
|
int err, offset; |
|
|
|
if (inode->i_ino == MSDOS_ROOT_INO) |
|
return 0; |
|
|
|
retry: |
|
i_pos = fat_i_pos_read(sbi, inode); |
|
if (!i_pos) |
|
return 0; |
|
|
|
fat_get_blknr_offset(sbi, i_pos, &blocknr, &offset); |
|
bh = sb_bread(sb, blocknr); |
|
if (!bh) { |
|
fat_msg(sb, KERN_ERR, "unable to read inode block " |
|
"for updating (i_pos %lld)", i_pos); |
|
return -EIO; |
|
} |
|
spin_lock(&sbi->inode_hash_lock); |
|
if (i_pos != MSDOS_I(inode)->i_pos) { |
|
spin_unlock(&sbi->inode_hash_lock); |
|
brelse(bh); |
|
goto retry; |
|
} |
|
|
|
raw_entry = &((struct msdos_dir_entry *) (bh->b_data))[offset]; |
|
if (S_ISDIR(inode->i_mode)) |
|
raw_entry->size = 0; |
|
else |
|
raw_entry->size = cpu_to_le32(inode->i_size); |
|
raw_entry->attr = fat_make_attrs(inode); |
|
fat_set_start(raw_entry, MSDOS_I(inode)->i_logstart); |
|
fat_time_unix2fat(sbi, &inode->i_mtime, &raw_entry->time, |
|
&raw_entry->date, NULL); |
|
if (sbi->options.isvfat) { |
|
__le16 atime; |
|
fat_time_unix2fat(sbi, &inode->i_ctime, &raw_entry->ctime, |
|
&raw_entry->cdate, &raw_entry->ctime_cs); |
|
fat_time_unix2fat(sbi, &inode->i_atime, &atime, |
|
&raw_entry->adate, NULL); |
|
} |
|
spin_unlock(&sbi->inode_hash_lock); |
|
mark_buffer_dirty(bh); |
|
err = 0; |
|
if (wait) |
|
err = sync_dirty_buffer(bh); |
|
brelse(bh); |
|
return err; |
|
} |
|
|
|
static int fat_write_inode(struct inode *inode, struct writeback_control *wbc) |
|
{ |
|
int err; |
|
|
|
if (inode->i_ino == MSDOS_FSINFO_INO) { |
|
struct super_block *sb = inode->i_sb; |
|
|
|
mutex_lock(&MSDOS_SB(sb)->s_lock); |
|
err = fat_clusters_flush(sb); |
|
mutex_unlock(&MSDOS_SB(sb)->s_lock); |
|
} else |
|
err = __fat_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL); |
|
|
|
return err; |
|
} |
|
|
|
int fat_sync_inode(struct inode *inode) |
|
{ |
|
return __fat_write_inode(inode, 1); |
|
} |
|
|
|
EXPORT_SYMBOL_GPL(fat_sync_inode); |
|
|
|
static int fat_show_options(struct seq_file *m, struct dentry *root); |
|
static const struct super_operations fat_sops = { |
|
.alloc_inode = fat_alloc_inode, |
|
.free_inode = fat_free_inode, |
|
.write_inode = fat_write_inode, |
|
.evict_inode = fat_evict_inode, |
|
.put_super = fat_put_super, |
|
.statfs = fat_statfs, |
|
.remount_fs = fat_remount, |
|
|
|
.show_options = fat_show_options, |
|
}; |
|
|
|
static int fat_show_options(struct seq_file *m, struct dentry *root) |
|
{ |
|
struct msdos_sb_info *sbi = MSDOS_SB(root->d_sb); |
|
struct fat_mount_options *opts = &sbi->options; |
|
int isvfat = opts->isvfat; |
|
|
|
if (!uid_eq(opts->fs_uid, GLOBAL_ROOT_UID)) |
|
seq_printf(m, ",uid=%u", |
|
from_kuid_munged(&init_user_ns, opts->fs_uid)); |
|
if (!gid_eq(opts->fs_gid, GLOBAL_ROOT_GID)) |
|
seq_printf(m, ",gid=%u", |
|
from_kgid_munged(&init_user_ns, opts->fs_gid)); |
|
seq_printf(m, ",fmask=%04o", opts->fs_fmask); |
|
seq_printf(m, ",dmask=%04o", opts->fs_dmask); |
|
if (opts->allow_utime) |
|
seq_printf(m, ",allow_utime=%04o", opts->allow_utime); |
|
if (sbi->nls_disk) |
|
/* strip "cp" prefix from displayed option */ |
|
seq_printf(m, ",codepage=%s", &sbi->nls_disk->charset[2]); |
|
if (isvfat) { |
|
if (sbi->nls_io) |
|
seq_printf(m, ",iocharset=%s", sbi->nls_io->charset); |
|
|
|
switch (opts->shortname) { |
|
case VFAT_SFN_DISPLAY_WIN95 | VFAT_SFN_CREATE_WIN95: |
|
seq_puts(m, ",shortname=win95"); |
|
break; |
|
case VFAT_SFN_DISPLAY_WINNT | VFAT_SFN_CREATE_WINNT: |
|
seq_puts(m, ",shortname=winnt"); |
|
break; |
|
case VFAT_SFN_DISPLAY_WINNT | VFAT_SFN_CREATE_WIN95: |
|
seq_puts(m, ",shortname=mixed"); |
|
break; |
|
case VFAT_SFN_DISPLAY_LOWER | VFAT_SFN_CREATE_WIN95: |
|
seq_puts(m, ",shortname=lower"); |
|
break; |
|
default: |
|
seq_puts(m, ",shortname=unknown"); |
|
break; |
|
} |
|
} |
|
if (opts->name_check != 'n') |
|
seq_printf(m, ",check=%c", opts->name_check); |
|
if (opts->usefree) |
|
seq_puts(m, ",usefree"); |
|
if (opts->quiet) |
|
seq_puts(m, ",quiet"); |
|
if (opts->showexec) |
|
seq_puts(m, ",showexec"); |
|
if (opts->sys_immutable) |
|
seq_puts(m, ",sys_immutable"); |
|
if (!isvfat) { |
|
if (opts->dotsOK) |
|
seq_puts(m, ",dotsOK=yes"); |
|
if (opts->nocase) |
|
seq_puts(m, ",nocase"); |
|
} else { |
|
if (opts->utf8) |
|
seq_puts(m, ",utf8"); |
|
if (opts->unicode_xlate) |
|
seq_puts(m, ",uni_xlate"); |
|
if (!opts->numtail) |
|
seq_puts(m, ",nonumtail"); |
|
if (opts->rodir) |
|
seq_puts(m, ",rodir"); |
|
} |
|
if (opts->flush) |
|
seq_puts(m, ",flush"); |
|
if (opts->tz_set) { |
|
if (opts->time_offset) |
|
seq_printf(m, ",time_offset=%d", opts->time_offset); |
|
else |
|
seq_puts(m, ",tz=UTC"); |
|
} |
|
if (opts->errors == FAT_ERRORS_CONT) |
|
seq_puts(m, ",errors=continue"); |
|
else if (opts->errors == FAT_ERRORS_PANIC) |
|
seq_puts(m, ",errors=panic"); |
|
else |
|
seq_puts(m, ",errors=remount-ro"); |
|
if (opts->nfs == FAT_NFS_NOSTALE_RO) |
|
seq_puts(m, ",nfs=nostale_ro"); |
|
else if (opts->nfs) |
|
seq_puts(m, ",nfs=stale_rw"); |
|
if (opts->discard) |
|
seq_puts(m, ",discard"); |
|
if (opts->dos1xfloppy) |
|
seq_puts(m, ",dos1xfloppy"); |
|
|
|
return 0; |
|
} |
|
|
|
enum { |
|
Opt_check_n, Opt_check_r, Opt_check_s, Opt_uid, Opt_gid, |
|
Opt_umask, Opt_dmask, Opt_fmask, Opt_allow_utime, Opt_codepage, |
|
Opt_usefree, Opt_nocase, Opt_quiet, Opt_showexec, Opt_debug, |
|
Opt_immutable, Opt_dots, Opt_nodots, |
|
Opt_charset, Opt_shortname_lower, Opt_shortname_win95, |
|
Opt_shortname_winnt, Opt_shortname_mixed, Opt_utf8_no, Opt_utf8_yes, |
|
Opt_uni_xl_no, Opt_uni_xl_yes, Opt_nonumtail_no, Opt_nonumtail_yes, |
|
Opt_obsolete, Opt_flush, Opt_tz_utc, Opt_rodir, Opt_err_cont, |
|
Opt_err_panic, Opt_err_ro, Opt_discard, Opt_nfs, Opt_time_offset, |
|
Opt_nfs_stale_rw, Opt_nfs_nostale_ro, Opt_err, Opt_dos1xfloppy, |
|
}; |
|
|
|
static const match_table_t fat_tokens = { |
|
{Opt_check_r, "check=relaxed"}, |
|
{Opt_check_s, "check=strict"}, |
|
{Opt_check_n, "check=normal"}, |
|
{Opt_check_r, "check=r"}, |
|
{Opt_check_s, "check=s"}, |
|
{Opt_check_n, "check=n"}, |
|
{Opt_uid, "uid=%u"}, |
|
{Opt_gid, "gid=%u"}, |
|
{Opt_umask, "umask=%o"}, |
|
{Opt_dmask, "dmask=%o"}, |
|
{Opt_fmask, "fmask=%o"}, |
|
{Opt_allow_utime, "allow_utime=%o"}, |
|
{Opt_codepage, "codepage=%u"}, |
|
{Opt_usefree, "usefree"}, |
|
{Opt_nocase, "nocase"}, |
|
{Opt_quiet, "quiet"}, |
|
{Opt_showexec, "showexec"}, |
|
{Opt_debug, "debug"}, |
|
{Opt_immutable, "sys_immutable"}, |
|
{Opt_flush, "flush"}, |
|
{Opt_tz_utc, "tz=UTC"}, |
|
{Opt_time_offset, "time_offset=%d"}, |
|
{Opt_err_cont, "errors=continue"}, |
|
{Opt_err_panic, "errors=panic"}, |
|
{Opt_err_ro, "errors=remount-ro"}, |
|
{Opt_discard, "discard"}, |
|
{Opt_nfs_stale_rw, "nfs"}, |
|
{Opt_nfs_stale_rw, "nfs=stale_rw"}, |
|
{Opt_nfs_nostale_ro, "nfs=nostale_ro"}, |
|
{Opt_dos1xfloppy, "dos1xfloppy"}, |
|
{Opt_obsolete, "conv=binary"}, |
|
{Opt_obsolete, "conv=text"}, |
|
{Opt_obsolete, "conv=auto"}, |
|
{Opt_obsolete, "conv=b"}, |
|
{Opt_obsolete, "conv=t"}, |
|
{Opt_obsolete, "conv=a"}, |
|
{Opt_obsolete, "fat=%u"}, |
|
{Opt_obsolete, "blocksize=%u"}, |
|
{Opt_obsolete, "cvf_format=%20s"}, |
|
{Opt_obsolete, "cvf_options=%100s"}, |
|
{Opt_obsolete, "posix"}, |
|
{Opt_err, NULL}, |
|
}; |
|
static const match_table_t msdos_tokens = { |
|
{Opt_nodots, "nodots"}, |
|
{Opt_nodots, "dotsOK=no"}, |
|
{Opt_dots, "dots"}, |
|
{Opt_dots, "dotsOK=yes"}, |
|
{Opt_err, NULL} |
|
}; |
|
static const match_table_t vfat_tokens = { |
|
{Opt_charset, "iocharset=%s"}, |
|
{Opt_shortname_lower, "shortname=lower"}, |
|
{Opt_shortname_win95, "shortname=win95"}, |
|
{Opt_shortname_winnt, "shortname=winnt"}, |
|
{Opt_shortname_mixed, "shortname=mixed"}, |
|
{Opt_utf8_no, "utf8=0"}, /* 0 or no or false */ |
|
{Opt_utf8_no, "utf8=no"}, |
|
{Opt_utf8_no, "utf8=false"}, |
|
{Opt_utf8_yes, "utf8=1"}, /* empty or 1 or yes or true */ |
|
{Opt_utf8_yes, "utf8=yes"}, |
|
{Opt_utf8_yes, "utf8=true"}, |
|
{Opt_utf8_yes, "utf8"}, |
|
{Opt_uni_xl_no, "uni_xlate=0"}, /* 0 or no or false */ |
|
{Opt_uni_xl_no, "uni_xlate=no"}, |
|
{Opt_uni_xl_no, "uni_xlate=false"}, |
|
{Opt_uni_xl_yes, "uni_xlate=1"}, /* empty or 1 or yes or true */ |
|
{Opt_uni_xl_yes, "uni_xlate=yes"}, |
|
{Opt_uni_xl_yes, "uni_xlate=true"}, |
|
{Opt_uni_xl_yes, "uni_xlate"}, |
|
{Opt_nonumtail_no, "nonumtail=0"}, /* 0 or no or false */ |
|
{Opt_nonumtail_no, "nonumtail=no"}, |
|
{Opt_nonumtail_no, "nonumtail=false"}, |
|
{Opt_nonumtail_yes, "nonumtail=1"}, /* empty or 1 or yes or true */ |
|
{Opt_nonumtail_yes, "nonumtail=yes"}, |
|
{Opt_nonumtail_yes, "nonumtail=true"}, |
|
{Opt_nonumtail_yes, "nonumtail"}, |
|
{Opt_rodir, "rodir"}, |
|
{Opt_err, NULL} |
|
}; |
|
|
|
static int parse_options(struct super_block *sb, char *options, int is_vfat, |
|
int silent, int *debug, struct fat_mount_options *opts) |
|
{ |
|
char *p; |
|
substring_t args[MAX_OPT_ARGS]; |
|
int option; |
|
char *iocharset; |
|
|
|
opts->isvfat = is_vfat; |
|
|
|
opts->fs_uid = current_uid(); |
|
opts->fs_gid = current_gid(); |
|
opts->fs_fmask = opts->fs_dmask = current_umask(); |
|
opts->allow_utime = -1; |
|
opts->codepage = fat_default_codepage; |
|
fat_reset_iocharset(opts); |
|
if (is_vfat) { |
|
opts->shortname = VFAT_SFN_DISPLAY_WINNT|VFAT_SFN_CREATE_WIN95; |
|
opts->rodir = 0; |
|
} else { |
|
opts->shortname = 0; |
|
opts->rodir = 1; |
|
} |
|
opts->name_check = 'n'; |
|
opts->quiet = opts->showexec = opts->sys_immutable = opts->dotsOK = 0; |
|
opts->unicode_xlate = 0; |
|
opts->numtail = 1; |
|
opts->usefree = opts->nocase = 0; |
|
opts->tz_set = 0; |
|
opts->nfs = 0; |
|
opts->errors = FAT_ERRORS_RO; |
|
*debug = 0; |
|
|
|
opts->utf8 = IS_ENABLED(CONFIG_FAT_DEFAULT_UTF8) && is_vfat; |
|
|
|
if (!options) |
|
goto out; |
|
|
|
while ((p = strsep(&options, ",")) != NULL) { |
|
int token; |
|
if (!*p) |
|
continue; |
|
|
|
token = match_token(p, fat_tokens, args); |
|
if (token == Opt_err) { |
|
if (is_vfat) |
|
token = match_token(p, vfat_tokens, args); |
|
else |
|
token = match_token(p, msdos_tokens, args); |
|
} |
|
switch (token) { |
|
case Opt_check_s: |
|
opts->name_check = 's'; |
|
break; |
|
case Opt_check_r: |
|
opts->name_check = 'r'; |
|
break; |
|
case Opt_check_n: |
|
opts->name_check = 'n'; |
|
break; |
|
case Opt_usefree: |
|
opts->usefree = 1; |
|
break; |
|
case Opt_nocase: |
|
if (!is_vfat) |
|
opts->nocase = 1; |
|
else { |
|
/* for backward compatibility */ |
|
opts->shortname = VFAT_SFN_DISPLAY_WIN95 |
|
| VFAT_SFN_CREATE_WIN95; |
|
} |
|
break; |
|
case Opt_quiet: |
|
opts->quiet = 1; |
|
break; |
|
case Opt_showexec: |
|
opts->showexec = 1; |
|
break; |
|
case Opt_debug: |
|
*debug = 1; |
|
break; |
|
case Opt_immutable: |
|
opts->sys_immutable = 1; |
|
break; |
|
case Opt_uid: |
|
if (match_int(&args[0], &option)) |
|
return -EINVAL; |
|
opts->fs_uid = make_kuid(current_user_ns(), option); |
|
if (!uid_valid(opts->fs_uid)) |
|
return -EINVAL; |
|
break; |
|
case Opt_gid: |
|
if (match_int(&args[0], &option)) |
|
return -EINVAL; |
|
opts->fs_gid = make_kgid(current_user_ns(), option); |
|
if (!gid_valid(opts->fs_gid)) |
|
return -EINVAL; |
|
break; |
|
case Opt_umask: |
|
if (match_octal(&args[0], &option)) |
|
return -EINVAL; |
|
opts->fs_fmask = opts->fs_dmask = option; |
|
break; |
|
case Opt_dmask: |
|
if (match_octal(&args[0], &option)) |
|
return -EINVAL; |
|
opts->fs_dmask = option; |
|
break; |
|
case Opt_fmask: |
|
if (match_octal(&args[0], &option)) |
|
return -EINVAL; |
|
opts->fs_fmask = option; |
|
break; |
|
case Opt_allow_utime: |
|
if (match_octal(&args[0], &option)) |
|
return -EINVAL; |
|
opts->allow_utime = option & (S_IWGRP | S_IWOTH); |
|
break; |
|
case Opt_codepage: |
|
if (match_int(&args[0], &option)) |
|
return -EINVAL; |
|
opts->codepage = option; |
|
break; |
|
case Opt_flush: |
|
opts->flush = 1; |
|
break; |
|
case Opt_time_offset: |
|
if (match_int(&args[0], &option)) |
|
return -EINVAL; |
|
/* |
|
* GMT+-12 zones may have DST corrections so at least |
|
* 13 hours difference is needed. Make the limit 24 |
|
* just in case someone invents something unusual. |
|
*/ |
|
if (option < -24 * 60 || option > 24 * 60) |
|
return -EINVAL; |
|
opts->tz_set = 1; |
|
opts->time_offset = option; |
|
break; |
|
case Opt_tz_utc: |
|
opts->tz_set = 1; |
|
opts->time_offset = 0; |
|
break; |
|
case Opt_err_cont: |
|
opts->errors = FAT_ERRORS_CONT; |
|
break; |
|
case Opt_err_panic: |
|
opts->errors = FAT_ERRORS_PANIC; |
|
break; |
|
case Opt_err_ro: |
|
opts->errors = FAT_ERRORS_RO; |
|
break; |
|
case Opt_nfs_stale_rw: |
|
opts->nfs = FAT_NFS_STALE_RW; |
|
break; |
|
case Opt_nfs_nostale_ro: |
|
opts->nfs = FAT_NFS_NOSTALE_RO; |
|
break; |
|
case Opt_dos1xfloppy: |
|
opts->dos1xfloppy = 1; |
|
break; |
|
|
|
/* msdos specific */ |
|
case Opt_dots: |
|
opts->dotsOK = 1; |
|
break; |
|
case Opt_nodots: |
|
opts->dotsOK = 0; |
|
break; |
|
|
|
/* vfat specific */ |
|
case Opt_charset: |
|
fat_reset_iocharset(opts); |
|
iocharset = match_strdup(&args[0]); |
|
if (!iocharset) |
|
return -ENOMEM; |
|
opts->iocharset = iocharset; |
|
break; |
|
case Opt_shortname_lower: |
|
opts->shortname = VFAT_SFN_DISPLAY_LOWER |
|
| VFAT_SFN_CREATE_WIN95; |
|
break; |
|
case Opt_shortname_win95: |
|
opts->shortname = VFAT_SFN_DISPLAY_WIN95 |
|
| VFAT_SFN_CREATE_WIN95; |
|
break; |
|
case Opt_shortname_winnt: |
|
opts->shortname = VFAT_SFN_DISPLAY_WINNT |
|
| VFAT_SFN_CREATE_WINNT; |
|
break; |
|
case Opt_shortname_mixed: |
|
opts->shortname = VFAT_SFN_DISPLAY_WINNT |
|
| VFAT_SFN_CREATE_WIN95; |
|
break; |
|
case Opt_utf8_no: /* 0 or no or false */ |
|
opts->utf8 = 0; |
|
break; |
|
case Opt_utf8_yes: /* empty or 1 or yes or true */ |
|
opts->utf8 = 1; |
|
break; |
|
case Opt_uni_xl_no: /* 0 or no or false */ |
|
opts->unicode_xlate = 0; |
|
break; |
|
case Opt_uni_xl_yes: /* empty or 1 or yes or true */ |
|
opts->unicode_xlate = 1; |
|
break; |
|
case Opt_nonumtail_no: /* 0 or no or false */ |
|
opts->numtail = 1; /* negated option */ |
|
break; |
|
case Opt_nonumtail_yes: /* empty or 1 or yes or true */ |
|
opts->numtail = 0; /* negated option */ |
|
break; |
|
case Opt_rodir: |
|
opts->rodir = 1; |
|
break; |
|
case Opt_discard: |
|
opts->discard = 1; |
|
break; |
|
|
|
/* obsolete mount options */ |
|
case Opt_obsolete: |
|
fat_msg(sb, KERN_INFO, "\"%s\" option is obsolete, " |
|
"not supported now", p); |
|
break; |
|
/* unknown option */ |
|
default: |
|
if (!silent) { |
|
fat_msg(sb, KERN_ERR, |
|
"Unrecognized mount option \"%s\" " |
|
"or missing value", p); |
|
} |
|
return -EINVAL; |
|
} |
|
} |
|
|
|
out: |
|
/* UTF-8 doesn't provide FAT semantics */ |
|
if (!strcmp(opts->iocharset, "utf8")) { |
|
fat_msg(sb, KERN_WARNING, "utf8 is not a recommended IO charset" |
|
" for FAT filesystems, filesystem will be " |
|
"case sensitive!"); |
|
} |
|
|
|
/* If user doesn't specify allow_utime, it's initialized from dmask. */ |
|
if (opts->allow_utime == (unsigned short)-1) |
|
opts->allow_utime = ~opts->fs_dmask & (S_IWGRP | S_IWOTH); |
|
if (opts->unicode_xlate) |
|
opts->utf8 = 0; |
|
if (opts->nfs == FAT_NFS_NOSTALE_RO) { |
|
sb->s_flags |= SB_RDONLY; |
|
sb->s_export_op = &fat_export_ops_nostale; |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static int fat_read_root(struct inode *inode) |
|
{ |
|
struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); |
|
int error; |
|
|
|
MSDOS_I(inode)->i_pos = MSDOS_ROOT_INO; |
|
inode->i_uid = sbi->options.fs_uid; |
|
inode->i_gid = sbi->options.fs_gid; |
|
inode_inc_iversion(inode); |
|
inode->i_generation = 0; |
|
inode->i_mode = fat_make_mode(sbi, ATTR_DIR, S_IRWXUGO); |
|
inode->i_op = sbi->dir_ops; |
|
inode->i_fop = &fat_dir_operations; |
|
if (is_fat32(sbi)) { |
|
MSDOS_I(inode)->i_start = sbi->root_cluster; |
|
error = fat_calc_dir_size(inode); |
|
if (error < 0) |
|
return error; |
|
} else { |
|
MSDOS_I(inode)->i_start = 0; |
|
inode->i_size = sbi->dir_entries * sizeof(struct msdos_dir_entry); |
|
} |
|
inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1)) |
|
& ~((loff_t)sbi->cluster_size - 1)) >> 9; |
|
MSDOS_I(inode)->i_logstart = 0; |
|
MSDOS_I(inode)->mmu_private = inode->i_size; |
|
|
|
fat_save_attrs(inode, ATTR_DIR); |
|
inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = 0; |
|
inode->i_mtime.tv_nsec = inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = 0; |
|
set_nlink(inode, fat_subdirs(inode)+2); |
|
|
|
return 0; |
|
} |
|
|
|
static unsigned long calc_fat_clusters(struct super_block *sb) |
|
{ |
|
struct msdos_sb_info *sbi = MSDOS_SB(sb); |
|
|
|
/* Divide first to avoid overflow */ |
|
if (!is_fat12(sbi)) { |
|
unsigned long ent_per_sec = sb->s_blocksize * 8 / sbi->fat_bits; |
|
return ent_per_sec * sbi->fat_length; |
|
} |
|
|
|
return sbi->fat_length * sb->s_blocksize * 8 / sbi->fat_bits; |
|
} |
|
|
|
static bool fat_bpb_is_zero(struct fat_boot_sector *b) |
|
{ |
|
if (get_unaligned_le16(&b->sector_size)) |
|
return false; |
|
if (b->sec_per_clus) |
|
return false; |
|
if (b->reserved) |
|
return false; |
|
if (b->fats) |
|
return false; |
|
if (get_unaligned_le16(&b->dir_entries)) |
|
return false; |
|
if (get_unaligned_le16(&b->sectors)) |
|
return false; |
|
if (b->media) |
|
return false; |
|
if (b->fat_length) |
|
return false; |
|
if (b->secs_track) |
|
return false; |
|
if (b->heads) |
|
return false; |
|
return true; |
|
} |
|
|
|
static int fat_read_bpb(struct super_block *sb, struct fat_boot_sector *b, |
|
int silent, struct fat_bios_param_block *bpb) |
|
{ |
|
int error = -EINVAL; |
|
|
|
/* Read in BPB ... */ |
|
memset(bpb, 0, sizeof(*bpb)); |
|
bpb->fat_sector_size = get_unaligned_le16(&b->sector_size); |
|
bpb->fat_sec_per_clus = b->sec_per_clus; |
|
bpb->fat_reserved = le16_to_cpu(b->reserved); |
|
bpb->fat_fats = b->fats; |
|
bpb->fat_dir_entries = get_unaligned_le16(&b->dir_entries); |
|
bpb->fat_sectors = get_unaligned_le16(&b->sectors); |
|
bpb->fat_fat_length = le16_to_cpu(b->fat_length); |
|
bpb->fat_total_sect = le32_to_cpu(b->total_sect); |
|
|
|
bpb->fat16_state = b->fat16.state; |
|
bpb->fat16_vol_id = get_unaligned_le32(b->fat16.vol_id); |
|
|
|
bpb->fat32_length = le32_to_cpu(b->fat32.length); |
|
bpb->fat32_root_cluster = le32_to_cpu(b->fat32.root_cluster); |
|
bpb->fat32_info_sector = le16_to_cpu(b->fat32.info_sector); |
|
bpb->fat32_state = b->fat32.state; |
|
bpb->fat32_vol_id = get_unaligned_le32(b->fat32.vol_id); |
|
|
|
/* Validate this looks like a FAT filesystem BPB */ |
|
if (!bpb->fat_reserved) { |
|
if (!silent) |
|
fat_msg(sb, KERN_ERR, |
|
"bogus number of reserved sectors"); |
|
goto out; |
|
} |
|
if (!bpb->fat_fats) { |
|
if (!silent) |
|
fat_msg(sb, KERN_ERR, "bogus number of FAT structure"); |
|
goto out; |
|
} |
|
|
|
/* |
|
* Earlier we checked here that b->secs_track and b->head are nonzero, |
|
* but it turns out valid FAT filesystems can have zero there. |
|
*/ |
|
|
|
if (!fat_valid_media(b->media)) { |
|
if (!silent) |
|
fat_msg(sb, KERN_ERR, "invalid media value (0x%02x)", |
|
(unsigned)b->media); |
|
goto out; |
|
} |
|
|
|
if (!is_power_of_2(bpb->fat_sector_size) |
|
|| (bpb->fat_sector_size < 512) |
|
|| (bpb->fat_sector_size > 4096)) { |
|
if (!silent) |
|
fat_msg(sb, KERN_ERR, "bogus logical sector size %u", |
|
(unsigned)bpb->fat_sector_size); |
|
goto out; |
|
} |
|
|
|
if (!is_power_of_2(bpb->fat_sec_per_clus)) { |
|
if (!silent) |
|
fat_msg(sb, KERN_ERR, "bogus sectors per cluster %u", |
|
(unsigned)bpb->fat_sec_per_clus); |
|
goto out; |
|
} |
|
|
|
if (bpb->fat_fat_length == 0 && bpb->fat32_length == 0) { |
|
if (!silent) |
|
fat_msg(sb, KERN_ERR, "bogus number of FAT sectors"); |
|
goto out; |
|
} |
|
|
|
error = 0; |
|
|
|
out: |
|
return error; |
|
} |
|
|
|
static int fat_read_static_bpb(struct super_block *sb, |
|
struct fat_boot_sector *b, int silent, |
|
struct fat_bios_param_block *bpb) |
|
{ |
|
static const char *notdos1x = "This doesn't look like a DOS 1.x volume"; |
|
|
|
struct fat_floppy_defaults *fdefaults = NULL; |
|
int error = -EINVAL; |
|
sector_t bd_sects; |
|
unsigned i; |
|
|
|
bd_sects = i_size_read(sb->s_bdev->bd_inode) / SECTOR_SIZE; |
|
|
|
/* 16-bit DOS 1.x reliably wrote bootstrap short-jmp code */ |
|
if (b->ignored[0] != 0xeb || b->ignored[2] != 0x90) { |
|
if (!silent) |
|
fat_msg(sb, KERN_ERR, |
|
"%s; no bootstrapping code", notdos1x); |
|
goto out; |
|
} |
|
|
|
/* |
|
* If any value in this region is non-zero, it isn't archaic |
|
* DOS. |
|
*/ |
|
if (!fat_bpb_is_zero(b)) { |
|
if (!silent) |
|
fat_msg(sb, KERN_ERR, |
|
"%s; DOS 2.x BPB is non-zero", notdos1x); |
|
goto out; |
|
} |
|
|
|
for (i = 0; i < ARRAY_SIZE(floppy_defaults); i++) { |
|
if (floppy_defaults[i].nr_sectors == bd_sects) { |
|
fdefaults = &floppy_defaults[i]; |
|
break; |
|
} |
|
} |
|
|
|
if (fdefaults == NULL) { |
|
if (!silent) |
|
fat_msg(sb, KERN_WARNING, |
|
"This looks like a DOS 1.x volume, but isn't a recognized floppy size (%llu sectors)", |
|
(u64)bd_sects); |
|
goto out; |
|
} |
|
|
|
if (!silent) |
|
fat_msg(sb, KERN_INFO, |
|
"This looks like a DOS 1.x volume; assuming default BPB values"); |
|
|
|
memset(bpb, 0, sizeof(*bpb)); |
|
bpb->fat_sector_size = SECTOR_SIZE; |
|
bpb->fat_sec_per_clus = fdefaults->sec_per_clus; |
|
bpb->fat_reserved = 1; |
|
bpb->fat_fats = 2; |
|
bpb->fat_dir_entries = fdefaults->dir_entries; |
|
bpb->fat_sectors = fdefaults->nr_sectors; |
|
bpb->fat_fat_length = fdefaults->fat_length; |
|
|
|
error = 0; |
|
|
|
out: |
|
return error; |
|
} |
|
|
|
/* |
|
* Read the super block of an MS-DOS FS. |
|
*/ |
|
int fat_fill_super(struct super_block *sb, void *data, int silent, int isvfat, |
|
void (*setup)(struct super_block *)) |
|
{ |
|
struct inode *root_inode = NULL, *fat_inode = NULL; |
|
struct inode *fsinfo_inode = NULL; |
|
struct buffer_head *bh; |
|
struct fat_bios_param_block bpb; |
|
struct msdos_sb_info *sbi; |
|
u16 logical_sector_size; |
|
u32 total_sectors, total_clusters, fat_clusters, rootdir_sectors; |
|
int debug; |
|
long error; |
|
char buf[50]; |
|
struct timespec64 ts; |
|
|
|
/* |
|
* GFP_KERNEL is ok here, because while we do hold the |
|
* superblock lock, memory pressure can't call back into |
|
* the filesystem, since we're only just about to mount |
|
* it and have no inodes etc active! |
|
*/ |
|
sbi = kzalloc(sizeof(struct msdos_sb_info), GFP_KERNEL); |
|
if (!sbi) |
|
return -ENOMEM; |
|
sb->s_fs_info = sbi; |
|
|
|
sb->s_flags |= SB_NODIRATIME; |
|
sb->s_magic = MSDOS_SUPER_MAGIC; |
|
sb->s_op = &fat_sops; |
|
sb->s_export_op = &fat_export_ops; |
|
/* |
|
* fat timestamps are complex and truncated by fat itself, so |
|
* we set 1 here to be fast |
|
*/ |
|
sb->s_time_gran = 1; |
|
mutex_init(&sbi->nfs_build_inode_lock); |
|
ratelimit_state_init(&sbi->ratelimit, DEFAULT_RATELIMIT_INTERVAL, |
|
DEFAULT_RATELIMIT_BURST); |
|
|
|
error = parse_options(sb, data, isvfat, silent, &debug, &sbi->options); |
|
if (error) |
|
goto out_fail; |
|
|
|
setup(sb); /* flavour-specific stuff that needs options */ |
|
|
|
error = -EIO; |
|
sb_min_blocksize(sb, 512); |
|
bh = sb_bread(sb, 0); |
|
if (bh == NULL) { |
|
fat_msg(sb, KERN_ERR, "unable to read boot sector"); |
|
goto out_fail; |
|
} |
|
|
|
error = fat_read_bpb(sb, (struct fat_boot_sector *)bh->b_data, silent, |
|
&bpb); |
|
if (error == -EINVAL && sbi->options.dos1xfloppy) |
|
error = fat_read_static_bpb(sb, |
|
(struct fat_boot_sector *)bh->b_data, silent, &bpb); |
|
brelse(bh); |
|
|
|
if (error == -EINVAL) |
|
goto out_invalid; |
|
else if (error) |
|
goto out_fail; |
|
|
|
logical_sector_size = bpb.fat_sector_size; |
|
sbi->sec_per_clus = bpb.fat_sec_per_clus; |
|
|
|
error = -EIO; |
|
if (logical_sector_size < sb->s_blocksize) { |
|
fat_msg(sb, KERN_ERR, "logical sector size too small for device" |
|
" (logical sector size = %u)", logical_sector_size); |
|
goto out_fail; |
|
} |
|
|
|
if (logical_sector_size > sb->s_blocksize) { |
|
struct buffer_head *bh_resize; |
|
|
|
if (!sb_set_blocksize(sb, logical_sector_size)) { |
|
fat_msg(sb, KERN_ERR, "unable to set blocksize %u", |
|
logical_sector_size); |
|
goto out_fail; |
|
} |
|
|
|
/* Verify that the larger boot sector is fully readable */ |
|
bh_resize = sb_bread(sb, 0); |
|
if (bh_resize == NULL) { |
|
fat_msg(sb, KERN_ERR, "unable to read boot sector" |
|
" (logical sector size = %lu)", |
|
sb->s_blocksize); |
|
goto out_fail; |
|
} |
|
brelse(bh_resize); |
|
} |
|
|
|
mutex_init(&sbi->s_lock); |
|
sbi->cluster_size = sb->s_blocksize * sbi->sec_per_clus; |
|
sbi->cluster_bits = ffs(sbi->cluster_size) - 1; |
|
sbi->fats = bpb.fat_fats; |
|
sbi->fat_bits = 0; /* Don't know yet */ |
|
sbi->fat_start = bpb.fat_reserved; |
|
sbi->fat_length = bpb.fat_fat_length; |
|
sbi->root_cluster = 0; |
|
sbi->free_clusters = -1; /* Don't know yet */ |
|
sbi->free_clus_valid = 0; |
|
sbi->prev_free = FAT_START_ENT; |
|
sb->s_maxbytes = 0xffffffff; |
|
fat_time_fat2unix(sbi, &ts, 0, cpu_to_le16(FAT_DATE_MIN), 0); |
|
sb->s_time_min = ts.tv_sec; |
|
|
|
fat_time_fat2unix(sbi, &ts, cpu_to_le16(FAT_TIME_MAX), |
|
cpu_to_le16(FAT_DATE_MAX), 0); |
|
sb->s_time_max = ts.tv_sec; |
|
|
|
if (!sbi->fat_length && bpb.fat32_length) { |
|
struct fat_boot_fsinfo *fsinfo; |
|
struct buffer_head *fsinfo_bh; |
|
|
|
/* Must be FAT32 */ |
|
sbi->fat_bits = 32; |
|
sbi->fat_length = bpb.fat32_length; |
|
sbi->root_cluster = bpb.fat32_root_cluster; |
|
|
|
/* MC - if info_sector is 0, don't multiply by 0 */ |
|
sbi->fsinfo_sector = bpb.fat32_info_sector; |
|
if (sbi->fsinfo_sector == 0) |
|
sbi->fsinfo_sector = 1; |
|
|
|
fsinfo_bh = sb_bread(sb, sbi->fsinfo_sector); |
|
if (fsinfo_bh == NULL) { |
|
fat_msg(sb, KERN_ERR, "bread failed, FSINFO block" |
|
" (sector = %lu)", sbi->fsinfo_sector); |
|
goto out_fail; |
|
} |
|
|
|
fsinfo = (struct fat_boot_fsinfo *)fsinfo_bh->b_data; |
|
if (!IS_FSINFO(fsinfo)) { |
|
fat_msg(sb, KERN_WARNING, "Invalid FSINFO signature: " |
|
"0x%08x, 0x%08x (sector = %lu)", |
|
le32_to_cpu(fsinfo->signature1), |
|
le32_to_cpu(fsinfo->signature2), |
|
sbi->fsinfo_sector); |
|
} else { |
|
if (sbi->options.usefree) |
|
sbi->free_clus_valid = 1; |
|
sbi->free_clusters = le32_to_cpu(fsinfo->free_clusters); |
|
sbi->prev_free = le32_to_cpu(fsinfo->next_cluster); |
|
} |
|
|
|
brelse(fsinfo_bh); |
|
} |
|
|
|
/* interpret volume ID as a little endian 32 bit integer */ |
|
if (is_fat32(sbi)) |
|
sbi->vol_id = bpb.fat32_vol_id; |
|
else /* fat 16 or 12 */ |
|
sbi->vol_id = bpb.fat16_vol_id; |
|
|
|
sbi->dir_per_block = sb->s_blocksize / sizeof(struct msdos_dir_entry); |
|
sbi->dir_per_block_bits = ffs(sbi->dir_per_block) - 1; |
|
|
|
sbi->dir_start = sbi->fat_start + sbi->fats * sbi->fat_length; |
|
sbi->dir_entries = bpb.fat_dir_entries; |
|
if (sbi->dir_entries & (sbi->dir_per_block - 1)) { |
|
if (!silent) |
|
fat_msg(sb, KERN_ERR, "bogus number of directory entries" |
|
" (%u)", sbi->dir_entries); |
|
goto out_invalid; |
|
} |
|
|
|
rootdir_sectors = sbi->dir_entries |
|
* sizeof(struct msdos_dir_entry) / sb->s_blocksize; |
|
sbi->data_start = sbi->dir_start + rootdir_sectors; |
|
total_sectors = bpb.fat_sectors; |
|
if (total_sectors == 0) |
|
total_sectors = bpb.fat_total_sect; |
|
|
|
total_clusters = (total_sectors - sbi->data_start) / sbi->sec_per_clus; |
|
|
|
if (!is_fat32(sbi)) |
|
sbi->fat_bits = (total_clusters > MAX_FAT12) ? 16 : 12; |
|
|
|
/* some OSes set FAT_STATE_DIRTY and clean it on unmount. */ |
|
if (is_fat32(sbi)) |
|
sbi->dirty = bpb.fat32_state & FAT_STATE_DIRTY; |
|
else /* fat 16 or 12 */ |
|
sbi->dirty = bpb.fat16_state & FAT_STATE_DIRTY; |
|
|
|
/* check that FAT table does not overflow */ |
|
fat_clusters = calc_fat_clusters(sb); |
|
total_clusters = min(total_clusters, fat_clusters - FAT_START_ENT); |
|
if (total_clusters > max_fat(sb)) { |
|
if (!silent) |
|
fat_msg(sb, KERN_ERR, "count of clusters too big (%u)", |
|
total_clusters); |
|
goto out_invalid; |
|
} |
|
|
|
sbi->max_cluster = total_clusters + FAT_START_ENT; |
|
/* check the free_clusters, it's not necessarily correct */ |
|
if (sbi->free_clusters != -1 && sbi->free_clusters > total_clusters) |
|
sbi->free_clusters = -1; |
|
/* check the prev_free, it's not necessarily correct */ |
|
sbi->prev_free %= sbi->max_cluster; |
|
if (sbi->prev_free < FAT_START_ENT) |
|
sbi->prev_free = FAT_START_ENT; |
|
|
|
/* set up enough so that it can read an inode */ |
|
fat_hash_init(sb); |
|
dir_hash_init(sb); |
|
fat_ent_access_init(sb); |
|
|
|
/* |
|
* The low byte of the first FAT entry must have the same value as |
|
* the media field of the boot sector. But in real world, too many |
|
* devices are writing wrong values. So, removed that validity check. |
|
* |
|
* The removed check compared the first FAT entry to a value dependent |
|
* on the media field like this: |
|
* == (0x0F00 | media), for FAT12 |
|
* == (0XFF00 | media), for FAT16 |
|
* == (0x0FFFFF | media), for FAT32 |
|
*/ |
|
|
|
error = -EINVAL; |
|
sprintf(buf, "cp%d", sbi->options.codepage); |
|
sbi->nls_disk = load_nls(buf); |
|
if (!sbi->nls_disk) { |
|
fat_msg(sb, KERN_ERR, "codepage %s not found", buf); |
|
goto out_fail; |
|
} |
|
|
|
/* FIXME: utf8 is using iocharset for upper/lower conversion */ |
|
if (sbi->options.isvfat) { |
|
sbi->nls_io = load_nls(sbi->options.iocharset); |
|
if (!sbi->nls_io) { |
|
fat_msg(sb, KERN_ERR, "IO charset %s not found", |
|
sbi->options.iocharset); |
|
goto out_fail; |
|
} |
|
} |
|
|
|
error = -ENOMEM; |
|
fat_inode = new_inode(sb); |
|
if (!fat_inode) |
|
goto out_fail; |
|
sbi->fat_inode = fat_inode; |
|
|
|
fsinfo_inode = new_inode(sb); |
|
if (!fsinfo_inode) |
|
goto out_fail; |
|
fsinfo_inode->i_ino = MSDOS_FSINFO_INO; |
|
sbi->fsinfo_inode = fsinfo_inode; |
|
insert_inode_hash(fsinfo_inode); |
|
|
|
root_inode = new_inode(sb); |
|
if (!root_inode) |
|
goto out_fail; |
|
root_inode->i_ino = MSDOS_ROOT_INO; |
|
inode_set_iversion(root_inode, 1); |
|
error = fat_read_root(root_inode); |
|
if (error < 0) { |
|
iput(root_inode); |
|
goto out_fail; |
|
} |
|
error = -ENOMEM; |
|
insert_inode_hash(root_inode); |
|
fat_attach(root_inode, 0); |
|
sb->s_root = d_make_root(root_inode); |
|
if (!sb->s_root) { |
|
fat_msg(sb, KERN_ERR, "get root inode failed"); |
|
goto out_fail; |
|
} |
|
|
|
if (sbi->options.discard) { |
|
struct request_queue *q = bdev_get_queue(sb->s_bdev); |
|
if (!blk_queue_discard(q)) |
|
fat_msg(sb, KERN_WARNING, |
|
"mounting with \"discard\" option, but " |
|
"the device does not support discard"); |
|
} |
|
|
|
fat_set_state(sb, 1, 0); |
|
return 0; |
|
|
|
out_invalid: |
|
error = -EINVAL; |
|
if (!silent) |
|
fat_msg(sb, KERN_INFO, "Can't find a valid FAT filesystem"); |
|
|
|
out_fail: |
|
if (fsinfo_inode) |
|
iput(fsinfo_inode); |
|
if (fat_inode) |
|
iput(fat_inode); |
|
unload_nls(sbi->nls_io); |
|
unload_nls(sbi->nls_disk); |
|
fat_reset_iocharset(&sbi->options); |
|
sb->s_fs_info = NULL; |
|
kfree(sbi); |
|
return error; |
|
} |
|
|
|
EXPORT_SYMBOL_GPL(fat_fill_super); |
|
|
|
/* |
|
* helper function for fat_flush_inodes. This writes both the inode |
|
* and the file data blocks, waiting for in flight data blocks before |
|
* the start of the call. It does not wait for any io started |
|
* during the call |
|
*/ |
|
static int writeback_inode(struct inode *inode) |
|
{ |
|
|
|
int ret; |
|
|
|
/* if we used wait=1, sync_inode_metadata waits for the io for the |
|
* inode to finish. So wait=0 is sent down to sync_inode_metadata |
|
* and filemap_fdatawrite is used for the data blocks |
|
*/ |
|
ret = sync_inode_metadata(inode, 0); |
|
if (!ret) |
|
ret = filemap_fdatawrite(inode->i_mapping); |
|
return ret; |
|
} |
|
|
|
/* |
|
* write data and metadata corresponding to i1 and i2. The io is |
|
* started but we do not wait for any of it to finish. |
|
* |
|
* filemap_flush is used for the block device, so if there is a dirty |
|
* page for a block already in flight, we will not wait and start the |
|
* io over again |
|
*/ |
|
int fat_flush_inodes(struct super_block *sb, struct inode *i1, struct inode *i2) |
|
{ |
|
int ret = 0; |
|
if (!MSDOS_SB(sb)->options.flush) |
|
return 0; |
|
if (i1) |
|
ret = writeback_inode(i1); |
|
if (!ret && i2) |
|
ret = writeback_inode(i2); |
|
if (!ret) { |
|
struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping; |
|
ret = filemap_flush(mapping); |
|
} |
|
return ret; |
|
} |
|
EXPORT_SYMBOL_GPL(fat_flush_inodes); |
|
|
|
static int __init init_fat_fs(void) |
|
{ |
|
int err; |
|
|
|
err = fat_cache_init(); |
|
if (err) |
|
return err; |
|
|
|
err = fat_init_inodecache(); |
|
if (err) |
|
goto failed; |
|
|
|
return 0; |
|
|
|
failed: |
|
fat_cache_destroy(); |
|
return err; |
|
} |
|
|
|
static void __exit exit_fat_fs(void) |
|
{ |
|
fat_cache_destroy(); |
|
fat_destroy_inodecache(); |
|
} |
|
|
|
module_init(init_fat_fs) |
|
module_exit(exit_fat_fs) |
|
|
|
MODULE_LICENSE("GPL");
|
|
|