From 871480933a1c28f8a9fed4c4d34d06c439a7a422 Mon Sep 17 00:00:00 2001 From: Srikant Patnaik Date: Sun, 11 Jan 2015 12:28:04 +0530 Subject: Moved, renamed, and deleted files The original directory structure was scattered and unorganized. Changes are basically to make it look like kernel structure. --- ANDROID_3.4.5/fs/fat/inode.c | 1619 ------------------------------------------ 1 file changed, 1619 deletions(-) delete mode 100644 ANDROID_3.4.5/fs/fat/inode.c (limited to 'ANDROID_3.4.5/fs/fat/inode.c') diff --git a/ANDROID_3.4.5/fs/fat/inode.c b/ANDROID_3.4.5/fs/fat/inode.c deleted file mode 100644 index d403f76c..00000000 --- a/ANDROID_3.4.5/fs/fat/inode.c +++ /dev/null @@ -1,1619 +0,0 @@ -/* - * linux/fs/fat/inode.c - * - * Written 1992,1993 by Werner Almesberger - * VFAT extensions by Gordon Chaffee, merged with msdos fs by Henrik Storner - * Rewritten for the constant inumbers support by Al Viro - * - * Fixes: - * - * Max Cohan: Fixed invalid FSINFO offset when info_sector is 0 - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include "fat.h" - -#ifndef CONFIG_FAT_DEFAULT_IOCHARSET -/* if user don't select VFAT, this is undefined. */ -#define CONFIG_FAT_DEFAULT_IOCHARSET "" -#endif - -static int fat_default_codepage = CONFIG_FAT_DEFAULT_CODEPAGE; -static char fat_default_iocharset[] = CONFIG_FAT_DEFAULT_IOCHARSET; - - -static int fat_add_cluster(struct inode *inode) -{ - int err, cluster; - - err = fat_alloc_clusters(inode, &cluster, 1); - if (err) - return err; - /* FIXME: this cluster should be added after data of this - * cluster is writed */ - err = fat_chain_add(inode, cluster, 1); - if (err) - fat_free_clusters(inode, cluster); - return err; -} - -static inline int __fat_get_block(struct inode *inode, sector_t iblock, - unsigned long *max_blocks, - struct buffer_head *bh_result, int create) -{ - struct super_block *sb = inode->i_sb; - struct msdos_sb_info *sbi = MSDOS_SB(sb); - unsigned long mapped_blocks; - sector_t phys; - int err, offset; - - err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create); - if (err) - return err; - if (phys) { - map_bh(bh_result, sb, phys); - *max_blocks = min(mapped_blocks, *max_blocks); - return 0; - } - if (!create) - return 0; - - if (iblock != MSDOS_I(inode)->mmu_private >> sb->s_blocksize_bits) { - fat_fs_error(sb, "corrupted file size (i_pos %lld, %lld)", - MSDOS_I(inode)->i_pos, MSDOS_I(inode)->mmu_private); - return -EIO; - } - - offset = (unsigned long)iblock & (sbi->sec_per_clus - 1); - if (!offset) { - /* TODO: multiple cluster allocation would be desirable. */ - err = fat_add_cluster(inode); - if (err) - return err; - } - /* available blocks on this cluster */ - mapped_blocks = sbi->sec_per_clus - offset; - - *max_blocks = min(mapped_blocks, *max_blocks); - MSDOS_I(inode)->mmu_private += *max_blocks << sb->s_blocksize_bits; - - err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create); - if (err) - return err; - - BUG_ON(!phys); - BUG_ON(*max_blocks != mapped_blocks); - set_buffer_new(bh_result); - map_bh(bh_result, sb, phys); - - return 0; -} - -static int fat_get_block(struct inode *inode, sector_t iblock, - struct buffer_head *bh_result, int create) -{ - struct super_block *sb = inode->i_sb; - unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits; - int err; - - err = __fat_get_block(inode, iblock, &max_blocks, bh_result, create); - if (err) - return err; - bh_result->b_size = max_blocks << sb->s_blocksize_bits; - return 0; -} - -static int fat_writepage(struct page *page, struct writeback_control *wbc) -{ - return block_write_full_page(page, fat_get_block, wbc); -} - -static int fat_writepages(struct address_space *mapping, - struct writeback_control *wbc) -{ - return mpage_writepages(mapping, wbc, fat_get_block); -} - -static int fat_readpage(struct file *file, struct page *page) -{ - return mpage_readpage(page, fat_get_block); -} - -static int fat_readpages(struct file *file, struct address_space *mapping, - struct list_head *pages, unsigned nr_pages) -{ - return mpage_readpages(mapping, pages, nr_pages, fat_get_block); -} - -static void fat_write_failed(struct address_space *mapping, loff_t to) -{ - struct inode *inode = mapping->host; - - if (to > inode->i_size) { - truncate_pagecache(inode, to, inode->i_size); - fat_truncate_blocks(inode, inode->i_size); - } -} - -static int fat_write_begin(struct file *file, struct address_space *mapping, - loff_t pos, unsigned len, unsigned flags, - struct page **pagep, void **fsdata) -{ - int err; - - *pagep = NULL; - err = cont_write_begin(file, mapping, pos, len, flags, - pagep, fsdata, fat_get_block, - &MSDOS_I(mapping->host)->mmu_private); - if (err < 0) - fat_write_failed(mapping, pos + len); - return err; -} - -static int fat_write_end(struct file *file, struct address_space *mapping, - loff_t pos, unsigned len, unsigned copied, - struct page *pagep, void *fsdata) -{ - struct inode *inode = mapping->host; - int err; - err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata); - if (err < len) - fat_write_failed(mapping, pos + len); - if (!(err < 0) && !(MSDOS_I(inode)->i_attrs & ATTR_ARCH)) { - inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC; - MSDOS_I(inode)->i_attrs |= ATTR_ARCH; - mark_inode_dirty(inode); - } - return err; -} - -static ssize_t fat_direct_IO(int rw, struct kiocb *iocb, - const struct iovec *iov, - loff_t offset, unsigned long nr_segs) -{ - struct file *file = iocb->ki_filp; - struct address_space *mapping = file->f_mapping; - struct inode *inode = mapping->host; - ssize_t ret; - - if (rw == WRITE) { - /* - * FIXME: blockdev_direct_IO() doesn't use ->write_begin(), - * so we need to update the ->mmu_private to block boundary. - * - * But we must fill the remaining area or hole by nul for - * updating ->mmu_private. - * - * Return 0, and fallback to normal buffered write. - */ - loff_t size = offset + iov_length(iov, nr_segs); - if (MSDOS_I(inode)->mmu_private < size) - return 0; - } - - /* - * FAT need to use the DIO_LOCKING for avoiding the race - * condition of fat_get_block() and ->truncate(). - */ - ret = blockdev_direct_IO(rw, iocb, inode, iov, offset, nr_segs, - fat_get_block); - if (ret < 0 && (rw & WRITE)) - fat_write_failed(mapping, offset + iov_length(iov, nr_segs)); - - return ret; -} - -static sector_t _fat_bmap(struct address_space *mapping, sector_t block) -{ - sector_t blocknr; - - /* fat_get_cluster() assumes the requested blocknr isn't truncated. */ - down_read(&MSDOS_I(mapping->host)->truncate_lock); - blocknr = generic_block_bmap(mapping, block, fat_get_block); - up_read(&MSDOS_I(mapping->host)->truncate_lock); - - return blocknr; -} - -static const struct address_space_operations fat_aops = { - .readpage = fat_readpage, - .readpages = fat_readpages, - .writepage = fat_writepage, - .writepages = fat_writepages, - .write_begin = fat_write_begin, - .write_end = fat_write_end, - .direct_IO = fat_direct_IO, - .bmap = _fat_bmap -}; - -/* - * New FAT inode stuff. We do the following: - * a) i_ino is constant and has nothing with on-disk location. - * b) FAT manages its own cache of directory entries. - * c) *This* cache is indexed by on-disk location. - * d) inode has an associated directory entry, all right, but - * it may be unhashed. - * e) currently entries are stored within struct inode. That should - * change. - * f) we deal with races in the following way: - * 1. readdir() and lookup() do FAT-dir-cache lookup. - * 2. rename() unhashes the F-d-c entry and rehashes it in - * a new place. - * 3. unlink() and rmdir() unhash F-d-c entry. - * 4. fat_write_inode() checks whether the thing is unhashed. - * If it is we silently return. If it isn't we do bread(), - * check if the location is still valid and retry if it - * isn't. Otherwise we do changes. - * 5. Spinlock is used to protect hash/unhash/location check/lookup - * 6. fat_evict_inode() unhashes the F-d-c entry. - * 7. lookup() and readdir() do igrab() if they find a F-d-c entry - * and consider negative result as cache miss. - */ - -static void fat_hash_init(struct super_block *sb) -{ - struct msdos_sb_info *sbi = MSDOS_SB(sb); - int i; - - spin_lock_init(&sbi->inode_hash_lock); - for (i = 0; i < FAT_HASH_SIZE; i++) - INIT_HLIST_HEAD(&sbi->inode_hashtable[i]); -} - -static inline unsigned long fat_hash(loff_t i_pos) -{ - return hash_32(i_pos, FAT_HASH_BITS); -} - -void fat_attach(struct inode *inode, loff_t i_pos) -{ - struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); - struct hlist_head *head = sbi->inode_hashtable + fat_hash(i_pos); - - spin_lock(&sbi->inode_hash_lock); - MSDOS_I(inode)->i_pos = i_pos; - hlist_add_head(&MSDOS_I(inode)->i_fat_hash, head); - spin_unlock(&sbi->inode_hash_lock); -} -EXPORT_SYMBOL_GPL(fat_attach); - -void fat_detach(struct inode *inode) -{ - struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); - spin_lock(&sbi->inode_hash_lock); - MSDOS_I(inode)->i_pos = 0; - hlist_del_init(&MSDOS_I(inode)->i_fat_hash); - spin_unlock(&sbi->inode_hash_lock); -} -EXPORT_SYMBOL_GPL(fat_detach); - -struct inode *fat_iget(struct super_block *sb, loff_t i_pos) -{ - struct msdos_sb_info *sbi = MSDOS_SB(sb); - struct hlist_head *head = sbi->inode_hashtable + fat_hash(i_pos); - struct hlist_node *_p; - struct msdos_inode_info *i; - struct inode *inode = NULL; - - spin_lock(&sbi->inode_hash_lock); - hlist_for_each_entry(i, _p, head, i_fat_hash) { - BUG_ON(i->vfs_inode.i_sb != sb); - if (i->i_pos != i_pos) - continue; - inode = igrab(&i->vfs_inode); - if (inode) - break; - } - spin_unlock(&sbi->inode_hash_lock); - return inode; -} - -static int is_exec(unsigned char *extension) -{ - unsigned char *exe_extensions = "EXECOMBAT", *walk; - - for (walk = exe_extensions; *walk; walk += 3) - if (!strncmp(extension, walk, 3)) - return 1; - return 0; -} - -static int fat_calc_dir_size(struct inode *inode) -{ - struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); - int ret, fclus, dclus; - - inode->i_size = 0; - if (MSDOS_I(inode)->i_start == 0) - return 0; - - ret = fat_get_cluster(inode, FAT_ENT_EOF, &fclus, &dclus); - if (ret < 0) - return ret; - inode->i_size = (fclus + 1) << sbi->cluster_bits; - - return 0; -} - -/* doesn't deal with root inode */ -static 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 = le16_to_cpu(de->start); - if (sbi->fat_bits == 32) - MSDOS_I(inode)->i_start |= (le16_to_cpu(de->starthi) << 16); - - 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)); - } 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 = le16_to_cpu(de->start); - if (sbi->fat_bits == 32) - MSDOS_I(inode)->i_start |= (le16_to_cpu(de->starthi) << 16); - - 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; -} - -struct inode *fat_build_inode(struct super_block *sb, - struct msdos_dir_entry *de, loff_t i_pos) -{ - struct inode *inode; - int err; - - 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: - return inode; -} - -EXPORT_SYMBOL_GPL(fat_build_inode); - -static void fat_evict_inode(struct inode *inode) -{ - truncate_inode_pages(&inode->i_data, 0); - if (!inode->i_nlink) { - inode->i_size = 0; - fat_truncate_blocks(inode, 0); - } - invalidate_inode_buffers(inode); - end_writeback(inode); - fat_cache_inval_inode(inode); - fat_detach(inode); -} - -static void fat_write_super(struct super_block *sb) -{ - lock_super(sb); - sb->s_dirt = 0; - - if (!(sb->s_flags & MS_RDONLY)) - fat_clusters_flush(sb); - unlock_super(sb); -} - -static int fat_sync_fs(struct super_block *sb, int wait) -{ - int err = 0; - - if (sb->s_dirt) { - lock_super(sb); - sb->s_dirt = 0; - err = fat_clusters_flush(sb); - unlock_super(sb); - } - - return err; -} - -static void fat_put_super(struct super_block *sb) -{ - struct msdos_sb_info *sbi = MSDOS_SB(sb); - - if (sb->s_dirt) - fat_write_super(sb); - - iput(sbi->fat_inode); - - unload_nls(sbi->nls_disk); - unload_nls(sbi->nls_io); - - if (sbi->options.iocharset != fat_default_iocharset) - kfree(sbi->options.iocharset); - - sb->s_fs_info = NULL; - kfree(sbi); -} - -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); - 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), - init_once); - if (fat_inode_cachep == NULL) - return -ENOMEM; - return 0; -} - -static void __exit fat_destroy_inodecache(void) -{ - kmem_cache_destroy(fat_inode_cachep); -} - -static int fat_remount(struct super_block *sb, int *flags, char *data) -{ - struct msdos_sb_info *sbi = MSDOS_SB(sb); - *flags |= MS_NODIRATIME | (sbi->options.isvfat ? 0 : MS_NOATIME); - 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 inline loff_t fat_i_pos_read(struct msdos_sb_info *sbi, - struct inode *inode) -{ - loff_t i_pos; -#if BITS_PER_LONG == 32 - spin_lock(&sbi->inode_hash_lock); -#endif - i_pos = MSDOS_I(inode)->i_pos; -#if BITS_PER_LONG == 32 - spin_unlock(&sbi->inode_hash_lock); -#endif - return i_pos; -} - -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; - int err; - - if (inode->i_ino == MSDOS_ROOT_INO) - return 0; - -retry: - i_pos = fat_i_pos_read(sbi, inode); - if (!i_pos) - return 0; - - bh = sb_bread(sb, i_pos >> sbi->dir_per_block_bits); - 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)) - [i_pos & (sbi->dir_per_block - 1)]; - 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); - raw_entry->start = cpu_to_le16(MSDOS_I(inode)->i_logstart); - raw_entry->starthi = cpu_to_le16(MSDOS_I(inode)->i_logstart >> 16); - 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) -{ - return __fat_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL); -} - -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, - .write_super = fat_write_super, - .sync_fs = fat_sync_fs, - .statfs = fat_statfs, - .remount_fs = fat_remount, - - .show_options = fat_show_options, -}; - -/* - * a FAT file handle with fhtype 3 is - * 0/ i_ino - for fast, reliable lookup if still in the cache - * 1/ i_generation - to see if i_ino is still valid - * bit 0 == 0 iff directory - * 2/ i_pos(8-39) - if ino has changed, but still in cache - * 3/ i_pos(4-7)|i_logstart - to semi-verify inode found at i_pos - * 4/ i_pos(0-3)|parent->i_logstart - maybe used to hunt for the file on disc - * - * Hack for NFSv2: Maximum FAT entry number is 28bits and maximum - * i_pos is 40bits (blocknr(32) + dir offset(8)), so two 4bits - * of i_logstart is used to store the directory entry offset. - */ - -static struct dentry *fat_fh_to_dentry(struct super_block *sb, - struct fid *fid, int fh_len, int fh_type) -{ - struct inode *inode = NULL; - u32 *fh = fid->raw; - - if (fh_len < 5 || fh_type != 3) - return NULL; - - inode = ilookup(sb, fh[0]); - if (!inode || inode->i_generation != fh[1]) { - if (inode) - iput(inode); - inode = NULL; - } - if (!inode) { - loff_t i_pos; - int i_logstart = fh[3] & 0x0fffffff; - - i_pos = (loff_t)fh[2] << 8; - i_pos |= ((fh[3] >> 24) & 0xf0) | (fh[4] >> 28); - - /* try 2 - see if i_pos is in F-d-c - * require i_logstart to be the same - * Will fail if you truncate and then re-write - */ - - inode = fat_iget(sb, i_pos); - if (inode && MSDOS_I(inode)->i_logstart != i_logstart) { - iput(inode); - inode = NULL; - } - } - - /* - * For now, do nothing if the inode is not found. - * - * What we could do is: - * - * - follow the file starting at fh[4], and record the ".." entry, - * and the name of the fh[2] entry. - * - then follow the ".." file finding the next step up. - * - * This way we build a path to the root of the tree. If this works, we - * lookup the path and so get this inode into the cache. Finally try - * the fat_iget lookup again. If that fails, then we are totally out - * of luck. But all that is for another day - */ - return d_obtain_alias(inode); -} - -static int -fat_encode_fh(struct dentry *de, __u32 *fh, int *lenp, int connectable) -{ - int len = *lenp; - struct inode *inode = de->d_inode; - u32 ipos_h, ipos_m, ipos_l; - - if (len < 5) { - *lenp = 5; - return 255; /* no room */ - } - - ipos_h = MSDOS_I(inode)->i_pos >> 8; - ipos_m = (MSDOS_I(inode)->i_pos & 0xf0) << 24; - ipos_l = (MSDOS_I(inode)->i_pos & 0x0f) << 28; - *lenp = 5; - fh[0] = inode->i_ino; - fh[1] = inode->i_generation; - fh[2] = ipos_h; - fh[3] = ipos_m | MSDOS_I(inode)->i_logstart; - spin_lock(&de->d_lock); - fh[4] = ipos_l | MSDOS_I(de->d_parent->d_inode)->i_logstart; - spin_unlock(&de->d_lock); - return 3; -} - -static struct dentry *fat_get_parent(struct dentry *child) -{ - struct super_block *sb = child->d_sb; - struct buffer_head *bh; - struct msdos_dir_entry *de; - loff_t i_pos; - struct dentry *parent; - struct inode *inode; - int err; - - lock_super(sb); - - err = fat_get_dotdot_entry(child->d_inode, &bh, &de, &i_pos); - if (err) { - parent = ERR_PTR(err); - goto out; - } - inode = fat_build_inode(sb, de, i_pos); - brelse(bh); - - parent = d_obtain_alias(inode); -out: - unlock_super(sb); - - return parent; -} - -static const struct export_operations fat_export_ops = { - .encode_fh = fat_encode_fh, - .fh_to_dentry = fat_fh_to_dentry, - .get_parent = fat_get_parent, -}; - -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 (opts->fs_uid != 0) - seq_printf(m, ",uid=%u", opts->fs_uid); - if (opts->fs_gid != 0) - seq_printf(m, ",gid=%u", 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) - seq_printf(m, ",codepage=%s", sbi->nls_disk->charset); - 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_utc) - 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->discard) - seq_puts(m, ",discard"); - - 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_err, -}; - -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_err_cont, "errors=continue"}, - {Opt_err_panic, "errors=panic"}, - {Opt_err_ro, "errors=remount-ro"}, - {Opt_discard, "discard"}, - {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->utf8 = opts->unicode_xlate = 0; - opts->numtail = 1; - opts->usefree = opts->nocase = 0; - opts->tz_utc = 0; - opts->errors = FAT_ERRORS_RO; - *debug = 0; - - 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 0; - opts->fs_uid = option; - break; - case Opt_gid: - if (match_int(&args[0], &option)) - return 0; - opts->fs_gid = option; - break; - case Opt_umask: - if (match_octal(&args[0], &option)) - return 0; - opts->fs_fmask = opts->fs_dmask = option; - break; - case Opt_dmask: - if (match_octal(&args[0], &option)) - return 0; - opts->fs_dmask = option; - break; - case Opt_fmask: - if (match_octal(&args[0], &option)) - return 0; - opts->fs_fmask = option; - break; - case Opt_allow_utime: - if (match_octal(&args[0], &option)) - return 0; - opts->allow_utime = option & (S_IWGRP | S_IWOTH); - break; - case Opt_codepage: - if (match_int(&args[0], &option)) - return 0; - opts->codepage = option; - break; - case Opt_flush: - opts->flush = 1; - break; - case Opt_tz_utc: - opts->tz_utc = 1; - 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; - - /* 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; - - return 0; -} - -static int fat_read_root(struct inode *inode) -{ - struct super_block *sb = inode->i_sb; - struct msdos_sb_info *sbi = MSDOS_SB(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 = 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; -} - -/* - * 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 buffer_head *bh; - struct fat_boot_sector *b; - struct fat_boot_bsx *bsx; - struct msdos_sb_info *sbi; - u16 logical_sector_size; - u32 total_sectors, total_clusters, fat_clusters, rootdir_sectors; - int debug; - unsigned int media; - long error; - char buf[50]; - - /* - * GFP_KERNEL is ok here, because while we do hold the - * supeblock 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; - 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; - } - - b = (struct fat_boot_sector *) bh->b_data; - if (!b->reserved) { - if (!silent) - fat_msg(sb, KERN_ERR, "bogus number of reserved sectors"); - brelse(bh); - goto out_invalid; - } - if (!b->fats) { - if (!silent) - fat_msg(sb, KERN_ERR, "bogus number of FAT structure"); - brelse(bh); - goto out_invalid; - } - - /* - * Earlier we checked here that b->secs_track and b->head are nonzero, - * but it turns out valid FAT filesystems can have zero there. - */ - - media = b->media; - if (!fat_valid_media(media)) { - if (!silent) - fat_msg(sb, KERN_ERR, "invalid media value (0x%02x)", - media); - brelse(bh); - goto out_invalid; - } - logical_sector_size = get_unaligned_le16(&b->sector_size); - if (!is_power_of_2(logical_sector_size) - || (logical_sector_size < 512) - || (logical_sector_size > 4096)) { - if (!silent) - fat_msg(sb, KERN_ERR, "bogus logical sector size %u", - logical_sector_size); - brelse(bh); - goto out_invalid; - } - sbi->sec_per_clus = b->sec_per_clus; - if (!is_power_of_2(sbi->sec_per_clus)) { - if (!silent) - fat_msg(sb, KERN_ERR, "bogus sectors per cluster %u", - sbi->sec_per_clus); - brelse(bh); - goto out_invalid; - } - - 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); - brelse(bh); - goto out_fail; - } - if (logical_sector_size > sb->s_blocksize) { - brelse(bh); - - if (!sb_set_blocksize(sb, logical_sector_size)) { - fat_msg(sb, KERN_ERR, "unable to set blocksize %u", - logical_sector_size); - goto out_fail; - } - bh = sb_bread(sb, 0); - if (bh == NULL) { - fat_msg(sb, KERN_ERR, "unable to read boot sector" - " (logical sector size = %lu)", - sb->s_blocksize); - goto out_fail; - } - b = (struct fat_boot_sector *) bh->b_data; - } - - sbi->cluster_size = sb->s_blocksize * sbi->sec_per_clus; - sbi->cluster_bits = ffs(sbi->cluster_size) - 1; - sbi->fats = b->fats; - sbi->fat_bits = 0; /* Don't know yet */ - sbi->fat_start = le16_to_cpu(b->reserved); - sbi->fat_length = le16_to_cpu(b->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 && b->fat32_length) { - struct fat_boot_fsinfo *fsinfo; - struct buffer_head *fsinfo_bh; - - /* Must be FAT32 */ - sbi->fat_bits = 32; - sbi->fat_length = le32_to_cpu(b->fat32_length); - sbi->root_cluster = le32_to_cpu(b->root_cluster); - - /* MC - if info_sector is 0, don't multiply by 0 */ - sbi->fsinfo_sector = le16_to_cpu(b->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); - brelse(bh); - goto out_fail; - } - - bsx = (struct fat_boot_bsx *)(bh->b_data + FAT32_BSX_OFFSET); - - fsinfo = (struct fat_boot_fsinfo *)fsinfo_bh->b_data; - if (!IS_FSINFO(fsinfo)) { - fat_msg(sb, KERN_WARNING, "Invalid FSINFO signature: " - "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); - } else { - bsx = (struct fat_boot_bsx *)(bh->b_data + FAT16_BSX_OFFSET); - } - - /* interpret volume ID as a little endian 32 bit integer */ - sbi->vol_id = (((u32)bsx->vol_id[0]) | ((u32)bsx->vol_id[1] << 8) | - ((u32)bsx->vol_id[2] << 16) | ((u32)bsx->vol_id[3] << 24)); - - sbi->dir_per_block = sb->s_blocksize / sizeof(struct msdos_dir_entry); - sbi->dir_per_block_bits = ffs(sbi->dir_per_block) - 1; - - sbi->dir_start = sbi->fat_start + sbi->fats * sbi->fat_length; - sbi->dir_entries = get_unaligned_le16(&b->dir_entries); - if (sbi->dir_entries & (sbi->dir_per_block - 1)) { - if (!silent) - fat_msg(sb, KERN_ERR, "bogus directroy-entries per block" - " (%u)", sbi->dir_entries); - brelse(bh); - 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 = get_unaligned_le16(&b->sectors); - if (total_sectors == 0) - total_sectors = le32_to_cpu(b->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; - - /* check that FAT table does not overflow */ - fat_clusters = sbi->fat_length * sb->s_blocksize * 8 / sbi->fat_bits; - 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); - brelse(bh); - 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; - - brelse(bh); - - /* set up enough so that it can read an inode */ - fat_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; - 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); - sb->s_root = d_make_root(root_inode); - if (!sb->s_root) { - fat_msg(sb, KERN_ERR, "get root inode failed"); - goto out_fail; - } - - return 0; - -out_invalid: - error = -EINVAL; - if (!silent) - fat_msg(sb, KERN_INFO, "Can't find a valid FAT filesystem"); - -out_fail: - 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; - struct address_space *mapping = inode->i_mapping; - struct writeback_control wbc = { - .sync_mode = WB_SYNC_NONE, - .nr_to_write = 0, - }; - /* if we used WB_SYNC_ALL, sync_inode waits for the io for the - * inode to finish. So WB_SYNC_NONE is sent down to sync_inode - * and filemap_fdatawrite is used for the data blocks - */ - ret = sync_inode(inode, &wbc); - if (!ret) - ret = filemap_fdatawrite(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"); -- cgit