![Deepa Dinamani](/assets/img/avatar_default.png)
CURRENT_TIME_SEC is not y2038 safe. current_time() will be transitioned to use 64 bit time along with vfs in a separate patch. There is no plan to transistion CURRENT_TIME_SEC to use y2038 safe time interfaces. current_time() will also be extended to use superblock range checking parameters when range checking is introduced. This works because alloc_super() fills in the the s_time_gran in super block to NSEC_PER_SEC. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
1942 lines
50 KiB
C
1942 lines
50 KiB
C
/*
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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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#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 "fat.h"
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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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* 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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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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int fat_add_cluster(struct inode *inode)
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{
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int err, cluster;
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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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*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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BUG_ON(!phys);
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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 int fat_readpages(struct file *file, struct address_space *mapping,
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struct list_head *pages, unsigned nr_pages)
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{
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return mpage_readpages(mapping, pages, nr_pages, 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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inode->i_mtime = inode->i_ctime = current_time(inode);
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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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.readpages = fat_readpages,
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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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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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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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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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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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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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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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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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return 0;
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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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if (dir->i_nlink < 2) {
|
|
/* Directory should have "."/".." entries at least. */
|
|
fat_fs_error(sb, "corrupted directory (invalid entries)");
|
|
return -EIO;
|
|
}
|
|
if (MSDOS_I(dir)->i_start == 0 ||
|
|
MSDOS_I(dir)->i_start == MSDOS_SB(sb)->root_cluster) {
|
|
/* Directory should point valid cluster. */
|
|
fat_fs_error(sb, "corrupted directory (invalid i_start)");
|
|
return -EIO;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* doesn't deal with root inode */
|
|
int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de)
|
|
{
|
|
struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
|
|
int error;
|
|
|
|
MSDOS_I(inode)->i_pos = 0;
|
|
inode->i_uid = sbi->options.fs_uid;
|
|
inode->i_gid = sbi->options.fs_gid;
|
|
inode->i_version++;
|
|
inode->i_generation = get_seconds();
|
|
|
|
if ((de->attr & ATTR_DIR) && !IS_FREE(de->name)) {
|
|
inode->i_generation &= ~1;
|
|
inode->i_mode = fat_make_mode(sbi, de->attr, S_IRWXUGO);
|
|
inode->i_op = sbi->dir_ops;
|
|
inode->i_fop = &fat_dir_operations;
|
|
|
|
MSDOS_I(inode)->i_start = fat_get_start(sbi, de);
|
|
MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start;
|
|
error = fat_calc_dir_size(inode);
|
|
if (error < 0)
|
|
return error;
|
|
MSDOS_I(inode)->mmu_private = inode->i_size;
|
|
|
|
set_nlink(inode, fat_subdirs(inode));
|
|
|
|
error = fat_validate_dir(inode);
|
|
if (error < 0)
|
|
return error;
|
|
} else { /* not a directory */
|
|
inode->i_generation |= 1;
|
|
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
|
|
inode->i_ctime = inode->i_atime = inode->i_mtime;
|
|
|
|
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->i_version = 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->s_flags & MS_RDONLY) && !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 (sbi->fat_bits == 32) {
|
|
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 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);
|
|
if (sbi->options.iocharset != fat_default_iocharset)
|
|
kfree(sbi->options.iocharset);
|
|
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);
|
|
return &ei->vfs_inode;
|
|
}
|
|
|
|
static void fat_i_callback(struct rcu_head *head)
|
|
{
|
|
struct inode *inode = container_of(head, struct inode, i_rcu);
|
|
kmem_cache_free(fat_inode_cachep, MSDOS_I(inode));
|
|
}
|
|
|
|
static void fat_destroy_inode(struct inode *inode)
|
|
{
|
|
call_rcu(&inode->i_rcu, fat_i_callback);
|
|
}
|
|
|
|
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)
|
|
{
|
|
int new_rdonly;
|
|
struct msdos_sb_info *sbi = MSDOS_SB(sb);
|
|
*flags |= MS_NODIRATIME | (sbi->options.isvfat ? 0 : MS_NOATIME);
|
|
|
|
sync_filesystem(sb);
|
|
|
|
/* make sure we update state on remount. */
|
|
new_rdonly = *flags & MS_RDONLY;
|
|
if (new_rdonly != (sb->s_flags & MS_RDONLY)) {
|
|
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.val[0] = (u32)id;
|
|
buf->f_fsid.val[1] = (u32)(id >> 32);
|
|
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,
|
|
.destroy_inode = fat_destroy_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;
|
|
opts->iocharset = fat_default_iocharset;
|
|
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:
|
|
if (opts->iocharset != fat_default_iocharset)
|
|
kfree(opts->iocharset);
|
|
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 |= MS_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->i_version++;
|
|
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 (sbi->fat_bits == 32) {
|
|
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 (sbi->fat_bits != 12) {
|
|
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;
|
|
}
|
|
|
|
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];
|
|
|
|
/*
|
|
* 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 |= MS_NODIRATIME;
|
|
sb->s_magic = MSDOS_SUPER_MAGIC;
|
|
sb->s_op = &fat_sops;
|
|
sb->s_export_op = &fat_export_ops;
|
|
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;
|
|
|
|
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 (sbi->fat_bits == 32)
|
|
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 (sbi->fat_bits != 32)
|
|
sbi->fat_bits = (total_clusters > MAX_FAT12) ? 16 : 12;
|
|
|
|
/* some OSes set FAT_STATE_DIRTY and clean it on unmount. */
|
|
if (sbi->fat_bits == 32)
|
|
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 FAT's first entry must have same value with
|
|
* media-field. But in real world, too many devices is
|
|
* writing wrong value. So, removed that validity check.
|
|
*
|
|
* if (FAT_FIRST_ENT(sb, media) != first)
|
|
*/
|
|
|
|
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;
|
|
MSDOS_I(fat_inode)->i_pos = 0;
|
|
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;
|
|
root_inode->i_version = 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);
|
|
if (sbi->options.iocharset != fat_default_iocharset)
|
|
kfree(sbi->options.iocharset);
|
|
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");
|