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1201 lines
28 KiB
1201 lines
28 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
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/* |
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* Copyright (C) 2012-2013 Samsung Electronics Co., Ltd. |
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*/ |
|
|
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#include <linux/slab.h> |
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#include <linux/compat.h> |
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#include <linux/bio.h> |
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#include <linux/buffer_head.h> |
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|
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#include "exfat_raw.h" |
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#include "exfat_fs.h" |
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|
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static int exfat_extract_uni_name(struct exfat_dentry *ep, |
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unsigned short *uniname) |
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{ |
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int i, len = 0; |
|
|
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for (i = 0; i < EXFAT_FILE_NAME_LEN; i++) { |
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*uniname = le16_to_cpu(ep->dentry.name.unicode_0_14[i]); |
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if (*uniname == 0x0) |
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return len; |
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uniname++; |
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len++; |
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} |
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|
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*uniname = 0x0; |
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return len; |
|
|
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} |
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|
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static void exfat_get_uniname_from_ext_entry(struct super_block *sb, |
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struct exfat_chain *p_dir, int entry, unsigned short *uniname) |
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{ |
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int i; |
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struct exfat_entry_set_cache *es; |
|
|
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es = exfat_get_dentry_set(sb, p_dir, entry, ES_ALL_ENTRIES); |
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if (!es) |
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return; |
|
|
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/* |
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* First entry : file entry |
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* Second entry : stream-extension entry |
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* Third entry : first file-name entry |
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* So, the index of first file-name dentry should start from 2. |
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*/ |
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for (i = 2; i < es->num_entries; i++) { |
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struct exfat_dentry *ep = exfat_get_dentry_cached(es, i); |
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|
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/* end of name entry */ |
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if (exfat_get_entry_type(ep) != TYPE_EXTEND) |
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break; |
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|
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exfat_extract_uni_name(ep, uniname); |
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uniname += EXFAT_FILE_NAME_LEN; |
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} |
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|
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exfat_free_dentry_set(es, false); |
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} |
|
|
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/* read a directory entry from the opened directory */ |
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static int exfat_readdir(struct inode *inode, loff_t *cpos, struct exfat_dir_entry *dir_entry) |
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{ |
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int i, dentries_per_clu, dentries_per_clu_bits = 0, num_ext; |
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unsigned int type, clu_offset; |
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sector_t sector; |
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struct exfat_chain dir, clu; |
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struct exfat_uni_name uni_name; |
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struct exfat_dentry *ep; |
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struct super_block *sb = inode->i_sb; |
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struct exfat_sb_info *sbi = EXFAT_SB(sb); |
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struct exfat_inode_info *ei = EXFAT_I(inode); |
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unsigned int dentry = EXFAT_B_TO_DEN(*cpos) & 0xFFFFFFFF; |
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struct buffer_head *bh; |
|
|
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/* check if the given file ID is opened */ |
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if (ei->type != TYPE_DIR) |
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return -EPERM; |
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|
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if (ei->entry == -1) |
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exfat_chain_set(&dir, sbi->root_dir, 0, ALLOC_FAT_CHAIN); |
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else |
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exfat_chain_set(&dir, ei->start_clu, |
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EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags); |
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|
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dentries_per_clu = sbi->dentries_per_clu; |
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dentries_per_clu_bits = ilog2(dentries_per_clu); |
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|
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clu_offset = dentry >> dentries_per_clu_bits; |
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exfat_chain_dup(&clu, &dir); |
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|
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if (clu.flags == ALLOC_NO_FAT_CHAIN) { |
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clu.dir += clu_offset; |
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clu.size -= clu_offset; |
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} else { |
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/* hint_information */ |
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if (clu_offset > 0 && ei->hint_bmap.off != EXFAT_EOF_CLUSTER && |
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ei->hint_bmap.off > 0 && clu_offset >= ei->hint_bmap.off) { |
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clu_offset -= ei->hint_bmap.off; |
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clu.dir = ei->hint_bmap.clu; |
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} |
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|
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while (clu_offset > 0) { |
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if (exfat_get_next_cluster(sb, &(clu.dir))) |
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return -EIO; |
|
|
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clu_offset--; |
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} |
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} |
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|
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while (clu.dir != EXFAT_EOF_CLUSTER) { |
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i = dentry & (dentries_per_clu - 1); |
|
|
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for ( ; i < dentries_per_clu; i++, dentry++) { |
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ep = exfat_get_dentry(sb, &clu, i, &bh, §or); |
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if (!ep) |
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return -EIO; |
|
|
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type = exfat_get_entry_type(ep); |
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if (type == TYPE_UNUSED) { |
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brelse(bh); |
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break; |
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} |
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|
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if (type != TYPE_FILE && type != TYPE_DIR) { |
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brelse(bh); |
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continue; |
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} |
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|
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num_ext = ep->dentry.file.num_ext; |
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dir_entry->attr = le16_to_cpu(ep->dentry.file.attr); |
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exfat_get_entry_time(sbi, &dir_entry->crtime, |
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ep->dentry.file.create_tz, |
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ep->dentry.file.create_time, |
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ep->dentry.file.create_date, |
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ep->dentry.file.create_time_cs); |
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exfat_get_entry_time(sbi, &dir_entry->mtime, |
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ep->dentry.file.modify_tz, |
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ep->dentry.file.modify_time, |
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ep->dentry.file.modify_date, |
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ep->dentry.file.modify_time_cs); |
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exfat_get_entry_time(sbi, &dir_entry->atime, |
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ep->dentry.file.access_tz, |
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ep->dentry.file.access_time, |
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ep->dentry.file.access_date, |
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0); |
|
|
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*uni_name.name = 0x0; |
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exfat_get_uniname_from_ext_entry(sb, &clu, i, |
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uni_name.name); |
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exfat_utf16_to_nls(sb, &uni_name, |
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dir_entry->namebuf.lfn, |
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dir_entry->namebuf.lfnbuf_len); |
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brelse(bh); |
|
|
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ep = exfat_get_dentry(sb, &clu, i + 1, &bh, NULL); |
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if (!ep) |
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return -EIO; |
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dir_entry->size = |
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le64_to_cpu(ep->dentry.stream.valid_size); |
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dir_entry->entry = dentry; |
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brelse(bh); |
|
|
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ei->hint_bmap.off = dentry >> dentries_per_clu_bits; |
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ei->hint_bmap.clu = clu.dir; |
|
|
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*cpos = EXFAT_DEN_TO_B(dentry + 1 + num_ext); |
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return 0; |
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} |
|
|
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if (clu.flags == ALLOC_NO_FAT_CHAIN) { |
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if (--clu.size > 0) |
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clu.dir++; |
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else |
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clu.dir = EXFAT_EOF_CLUSTER; |
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} else { |
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if (exfat_get_next_cluster(sb, &(clu.dir))) |
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return -EIO; |
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} |
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} |
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|
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dir_entry->namebuf.lfn[0] = '\0'; |
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*cpos = EXFAT_DEN_TO_B(dentry); |
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return 0; |
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} |
|
|
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static void exfat_init_namebuf(struct exfat_dentry_namebuf *nb) |
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{ |
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nb->lfn = NULL; |
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nb->lfnbuf_len = 0; |
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} |
|
|
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static int exfat_alloc_namebuf(struct exfat_dentry_namebuf *nb) |
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{ |
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nb->lfn = __getname(); |
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if (!nb->lfn) |
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return -ENOMEM; |
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nb->lfnbuf_len = MAX_VFSNAME_BUF_SIZE; |
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return 0; |
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} |
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|
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static void exfat_free_namebuf(struct exfat_dentry_namebuf *nb) |
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{ |
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if (!nb->lfn) |
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return; |
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|
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__putname(nb->lfn); |
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exfat_init_namebuf(nb); |
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} |
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|
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/* skip iterating emit_dots when dir is empty */ |
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#define ITER_POS_FILLED_DOTS (2) |
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static int exfat_iterate(struct file *filp, struct dir_context *ctx) |
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{ |
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struct inode *inode = filp->f_path.dentry->d_inode; |
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struct super_block *sb = inode->i_sb; |
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struct inode *tmp; |
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struct exfat_dir_entry de; |
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struct exfat_dentry_namebuf *nb = &(de.namebuf); |
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struct exfat_inode_info *ei = EXFAT_I(inode); |
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unsigned long inum; |
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loff_t cpos, i_pos; |
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int err = 0, fake_offset = 0; |
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|
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exfat_init_namebuf(nb); |
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mutex_lock(&EXFAT_SB(sb)->s_lock); |
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|
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cpos = ctx->pos; |
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if (!dir_emit_dots(filp, ctx)) |
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goto unlock; |
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|
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if (ctx->pos == ITER_POS_FILLED_DOTS) { |
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cpos = 0; |
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fake_offset = 1; |
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} |
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|
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if (cpos & (DENTRY_SIZE - 1)) { |
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err = -ENOENT; |
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goto unlock; |
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} |
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|
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/* name buffer should be allocated before use */ |
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err = exfat_alloc_namebuf(nb); |
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if (err) |
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goto unlock; |
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get_new: |
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if (cpos >= i_size_read(inode)) |
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goto end_of_dir; |
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|
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err = exfat_readdir(inode, &cpos, &de); |
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if (err) { |
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/* |
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* At least we tried to read a sector. Move cpos to next sector |
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* position (should be aligned). |
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*/ |
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if (err == -EIO) { |
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cpos += 1 << (sb->s_blocksize_bits); |
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cpos &= ~(sb->s_blocksize - 1); |
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} |
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|
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err = -EIO; |
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goto end_of_dir; |
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} |
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|
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if (!nb->lfn[0]) |
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goto end_of_dir; |
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i_pos = ((loff_t)ei->start_clu << 32) | (de.entry & 0xffffffff); |
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tmp = exfat_iget(sb, i_pos); |
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if (tmp) { |
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inum = tmp->i_ino; |
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iput(tmp); |
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} else { |
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inum = iunique(sb, EXFAT_ROOT_INO); |
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} |
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|
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/* |
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* Before calling dir_emit(), sb_lock should be released. |
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* Because page fault can occur in dir_emit() when the size |
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* of buffer given from user is larger than one page size. |
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*/ |
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mutex_unlock(&EXFAT_SB(sb)->s_lock); |
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if (!dir_emit(ctx, nb->lfn, strlen(nb->lfn), inum, |
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(de.attr & ATTR_SUBDIR) ? DT_DIR : DT_REG)) |
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goto out_unlocked; |
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mutex_lock(&EXFAT_SB(sb)->s_lock); |
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ctx->pos = cpos; |
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goto get_new; |
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|
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end_of_dir: |
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if (!cpos && fake_offset) |
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cpos = ITER_POS_FILLED_DOTS; |
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ctx->pos = cpos; |
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unlock: |
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mutex_unlock(&EXFAT_SB(sb)->s_lock); |
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out_unlocked: |
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/* |
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* To improve performance, free namebuf after unlock sb_lock. |
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* If namebuf is not allocated, this function do nothing |
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*/ |
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exfat_free_namebuf(nb); |
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return err; |
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} |
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|
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const struct file_operations exfat_dir_operations = { |
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.llseek = generic_file_llseek, |
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.read = generic_read_dir, |
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.iterate = exfat_iterate, |
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.unlocked_ioctl = exfat_ioctl, |
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#ifdef CONFIG_COMPAT |
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.compat_ioctl = exfat_compat_ioctl, |
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#endif |
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.fsync = exfat_file_fsync, |
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}; |
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|
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int exfat_alloc_new_dir(struct inode *inode, struct exfat_chain *clu) |
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{ |
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int ret; |
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|
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exfat_chain_set(clu, EXFAT_EOF_CLUSTER, 0, ALLOC_NO_FAT_CHAIN); |
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|
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ret = exfat_alloc_cluster(inode, 1, clu, IS_DIRSYNC(inode)); |
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if (ret) |
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return ret; |
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|
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return exfat_zeroed_cluster(inode, clu->dir); |
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} |
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|
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int exfat_calc_num_entries(struct exfat_uni_name *p_uniname) |
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{ |
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int len; |
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|
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len = p_uniname->name_len; |
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if (len == 0) |
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return -EINVAL; |
|
|
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/* 1 file entry + 1 stream entry + name entries */ |
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return ((len - 1) / EXFAT_FILE_NAME_LEN + 3); |
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} |
|
|
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unsigned int exfat_get_entry_type(struct exfat_dentry *ep) |
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{ |
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if (ep->type == EXFAT_UNUSED) |
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return TYPE_UNUSED; |
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if (IS_EXFAT_DELETED(ep->type)) |
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return TYPE_DELETED; |
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if (ep->type == EXFAT_INVAL) |
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return TYPE_INVALID; |
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if (IS_EXFAT_CRITICAL_PRI(ep->type)) { |
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if (ep->type == EXFAT_BITMAP) |
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return TYPE_BITMAP; |
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if (ep->type == EXFAT_UPCASE) |
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return TYPE_UPCASE; |
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if (ep->type == EXFAT_VOLUME) |
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return TYPE_VOLUME; |
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if (ep->type == EXFAT_FILE) { |
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if (le16_to_cpu(ep->dentry.file.attr) & ATTR_SUBDIR) |
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return TYPE_DIR; |
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return TYPE_FILE; |
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} |
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return TYPE_CRITICAL_PRI; |
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} |
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if (IS_EXFAT_BENIGN_PRI(ep->type)) { |
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if (ep->type == EXFAT_GUID) |
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return TYPE_GUID; |
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if (ep->type == EXFAT_PADDING) |
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return TYPE_PADDING; |
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if (ep->type == EXFAT_ACLTAB) |
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return TYPE_ACLTAB; |
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return TYPE_BENIGN_PRI; |
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} |
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if (IS_EXFAT_CRITICAL_SEC(ep->type)) { |
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if (ep->type == EXFAT_STREAM) |
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return TYPE_STREAM; |
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if (ep->type == EXFAT_NAME) |
|
return TYPE_EXTEND; |
|
if (ep->type == EXFAT_ACL) |
|
return TYPE_ACL; |
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return TYPE_CRITICAL_SEC; |
|
} |
|
return TYPE_BENIGN_SEC; |
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} |
|
|
|
static void exfat_set_entry_type(struct exfat_dentry *ep, unsigned int type) |
|
{ |
|
if (type == TYPE_UNUSED) { |
|
ep->type = EXFAT_UNUSED; |
|
} else if (type == TYPE_DELETED) { |
|
ep->type &= EXFAT_DELETE; |
|
} else if (type == TYPE_STREAM) { |
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ep->type = EXFAT_STREAM; |
|
} else if (type == TYPE_EXTEND) { |
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ep->type = EXFAT_NAME; |
|
} else if (type == TYPE_BITMAP) { |
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ep->type = EXFAT_BITMAP; |
|
} else if (type == TYPE_UPCASE) { |
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ep->type = EXFAT_UPCASE; |
|
} else if (type == TYPE_VOLUME) { |
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ep->type = EXFAT_VOLUME; |
|
} else if (type == TYPE_DIR) { |
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ep->type = EXFAT_FILE; |
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ep->dentry.file.attr = cpu_to_le16(ATTR_SUBDIR); |
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} else if (type == TYPE_FILE) { |
|
ep->type = EXFAT_FILE; |
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ep->dentry.file.attr = cpu_to_le16(ATTR_ARCHIVE); |
|
} |
|
} |
|
|
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static void exfat_init_stream_entry(struct exfat_dentry *ep, |
|
unsigned char flags, unsigned int start_clu, |
|
unsigned long long size) |
|
{ |
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exfat_set_entry_type(ep, TYPE_STREAM); |
|
ep->dentry.stream.flags = flags; |
|
ep->dentry.stream.start_clu = cpu_to_le32(start_clu); |
|
ep->dentry.stream.valid_size = cpu_to_le64(size); |
|
ep->dentry.stream.size = cpu_to_le64(size); |
|
} |
|
|
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static void exfat_init_name_entry(struct exfat_dentry *ep, |
|
unsigned short *uniname) |
|
{ |
|
int i; |
|
|
|
exfat_set_entry_type(ep, TYPE_EXTEND); |
|
ep->dentry.name.flags = 0x0; |
|
|
|
for (i = 0; i < EXFAT_FILE_NAME_LEN; i++) { |
|
if (*uniname != 0x0) { |
|
ep->dentry.name.unicode_0_14[i] = cpu_to_le16(*uniname); |
|
uniname++; |
|
} else { |
|
ep->dentry.name.unicode_0_14[i] = 0x0; |
|
} |
|
} |
|
} |
|
|
|
int exfat_init_dir_entry(struct inode *inode, struct exfat_chain *p_dir, |
|
int entry, unsigned int type, unsigned int start_clu, |
|
unsigned long long size) |
|
{ |
|
struct super_block *sb = inode->i_sb; |
|
struct exfat_sb_info *sbi = EXFAT_SB(sb); |
|
struct timespec64 ts = current_time(inode); |
|
sector_t sector; |
|
struct exfat_dentry *ep; |
|
struct buffer_head *bh; |
|
|
|
/* |
|
* We cannot use exfat_get_dentry_set here because file ep is not |
|
* initialized yet. |
|
*/ |
|
ep = exfat_get_dentry(sb, p_dir, entry, &bh, §or); |
|
if (!ep) |
|
return -EIO; |
|
|
|
exfat_set_entry_type(ep, type); |
|
exfat_set_entry_time(sbi, &ts, |
|
&ep->dentry.file.create_tz, |
|
&ep->dentry.file.create_time, |
|
&ep->dentry.file.create_date, |
|
&ep->dentry.file.create_time_cs); |
|
exfat_set_entry_time(sbi, &ts, |
|
&ep->dentry.file.modify_tz, |
|
&ep->dentry.file.modify_time, |
|
&ep->dentry.file.modify_date, |
|
&ep->dentry.file.modify_time_cs); |
|
exfat_set_entry_time(sbi, &ts, |
|
&ep->dentry.file.access_tz, |
|
&ep->dentry.file.access_time, |
|
&ep->dentry.file.access_date, |
|
NULL); |
|
|
|
exfat_update_bh(bh, IS_DIRSYNC(inode)); |
|
brelse(bh); |
|
|
|
ep = exfat_get_dentry(sb, p_dir, entry + 1, &bh, §or); |
|
if (!ep) |
|
return -EIO; |
|
|
|
exfat_init_stream_entry(ep, |
|
(type == TYPE_FILE) ? ALLOC_FAT_CHAIN : ALLOC_NO_FAT_CHAIN, |
|
start_clu, size); |
|
exfat_update_bh(bh, IS_DIRSYNC(inode)); |
|
brelse(bh); |
|
|
|
return 0; |
|
} |
|
|
|
int exfat_update_dir_chksum(struct inode *inode, struct exfat_chain *p_dir, |
|
int entry) |
|
{ |
|
struct super_block *sb = inode->i_sb; |
|
int ret = 0; |
|
int i, num_entries; |
|
sector_t sector; |
|
u16 chksum; |
|
struct exfat_dentry *ep, *fep; |
|
struct buffer_head *fbh, *bh; |
|
|
|
fep = exfat_get_dentry(sb, p_dir, entry, &fbh, §or); |
|
if (!fep) |
|
return -EIO; |
|
|
|
num_entries = fep->dentry.file.num_ext + 1; |
|
chksum = exfat_calc_chksum16(fep, DENTRY_SIZE, 0, CS_DIR_ENTRY); |
|
|
|
for (i = 1; i < num_entries; i++) { |
|
ep = exfat_get_dentry(sb, p_dir, entry + i, &bh, NULL); |
|
if (!ep) { |
|
ret = -EIO; |
|
goto release_fbh; |
|
} |
|
chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, chksum, |
|
CS_DEFAULT); |
|
brelse(bh); |
|
} |
|
|
|
fep->dentry.file.checksum = cpu_to_le16(chksum); |
|
exfat_update_bh(fbh, IS_DIRSYNC(inode)); |
|
release_fbh: |
|
brelse(fbh); |
|
return ret; |
|
} |
|
|
|
int exfat_init_ext_entry(struct inode *inode, struct exfat_chain *p_dir, |
|
int entry, int num_entries, struct exfat_uni_name *p_uniname) |
|
{ |
|
struct super_block *sb = inode->i_sb; |
|
int i; |
|
sector_t sector; |
|
unsigned short *uniname = p_uniname->name; |
|
struct exfat_dentry *ep; |
|
struct buffer_head *bh; |
|
int sync = IS_DIRSYNC(inode); |
|
|
|
ep = exfat_get_dentry(sb, p_dir, entry, &bh, §or); |
|
if (!ep) |
|
return -EIO; |
|
|
|
ep->dentry.file.num_ext = (unsigned char)(num_entries - 1); |
|
exfat_update_bh(bh, sync); |
|
brelse(bh); |
|
|
|
ep = exfat_get_dentry(sb, p_dir, entry + 1, &bh, §or); |
|
if (!ep) |
|
return -EIO; |
|
|
|
ep->dentry.stream.name_len = p_uniname->name_len; |
|
ep->dentry.stream.name_hash = cpu_to_le16(p_uniname->name_hash); |
|
exfat_update_bh(bh, sync); |
|
brelse(bh); |
|
|
|
for (i = EXFAT_FIRST_CLUSTER; i < num_entries; i++) { |
|
ep = exfat_get_dentry(sb, p_dir, entry + i, &bh, §or); |
|
if (!ep) |
|
return -EIO; |
|
|
|
exfat_init_name_entry(ep, uniname); |
|
exfat_update_bh(bh, sync); |
|
brelse(bh); |
|
uniname += EXFAT_FILE_NAME_LEN; |
|
} |
|
|
|
exfat_update_dir_chksum(inode, p_dir, entry); |
|
return 0; |
|
} |
|
|
|
int exfat_remove_entries(struct inode *inode, struct exfat_chain *p_dir, |
|
int entry, int order, int num_entries) |
|
{ |
|
struct super_block *sb = inode->i_sb; |
|
int i; |
|
sector_t sector; |
|
struct exfat_dentry *ep; |
|
struct buffer_head *bh; |
|
|
|
for (i = order; i < num_entries; i++) { |
|
ep = exfat_get_dentry(sb, p_dir, entry + i, &bh, §or); |
|
if (!ep) |
|
return -EIO; |
|
|
|
exfat_set_entry_type(ep, TYPE_DELETED); |
|
exfat_update_bh(bh, IS_DIRSYNC(inode)); |
|
brelse(bh); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
void exfat_update_dir_chksum_with_entry_set(struct exfat_entry_set_cache *es) |
|
{ |
|
int chksum_type = CS_DIR_ENTRY, i; |
|
unsigned short chksum = 0; |
|
struct exfat_dentry *ep; |
|
|
|
for (i = 0; i < es->num_entries; i++) { |
|
ep = exfat_get_dentry_cached(es, i); |
|
chksum = exfat_calc_chksum16(ep, DENTRY_SIZE, chksum, |
|
chksum_type); |
|
chksum_type = CS_DEFAULT; |
|
} |
|
ep = exfat_get_dentry_cached(es, 0); |
|
ep->dentry.file.checksum = cpu_to_le16(chksum); |
|
es->modified = true; |
|
} |
|
|
|
int exfat_free_dentry_set(struct exfat_entry_set_cache *es, int sync) |
|
{ |
|
int i, err = 0; |
|
|
|
if (es->modified) |
|
err = exfat_update_bhs(es->bh, es->num_bh, sync); |
|
|
|
for (i = 0; i < es->num_bh; i++) |
|
if (err) |
|
bforget(es->bh[i]); |
|
else |
|
brelse(es->bh[i]); |
|
kfree(es); |
|
return err; |
|
} |
|
|
|
static int exfat_walk_fat_chain(struct super_block *sb, |
|
struct exfat_chain *p_dir, unsigned int byte_offset, |
|
unsigned int *clu) |
|
{ |
|
struct exfat_sb_info *sbi = EXFAT_SB(sb); |
|
unsigned int clu_offset; |
|
unsigned int cur_clu; |
|
|
|
clu_offset = EXFAT_B_TO_CLU(byte_offset, sbi); |
|
cur_clu = p_dir->dir; |
|
|
|
if (p_dir->flags == ALLOC_NO_FAT_CHAIN) { |
|
cur_clu += clu_offset; |
|
} else { |
|
while (clu_offset > 0) { |
|
if (exfat_get_next_cluster(sb, &cur_clu)) |
|
return -EIO; |
|
if (cur_clu == EXFAT_EOF_CLUSTER) { |
|
exfat_fs_error(sb, |
|
"invalid dentry access beyond EOF (clu : %u, eidx : %d)", |
|
p_dir->dir, |
|
EXFAT_B_TO_DEN(byte_offset)); |
|
return -EIO; |
|
} |
|
clu_offset--; |
|
} |
|
} |
|
|
|
*clu = cur_clu; |
|
return 0; |
|
} |
|
|
|
int exfat_find_location(struct super_block *sb, struct exfat_chain *p_dir, |
|
int entry, sector_t *sector, int *offset) |
|
{ |
|
int ret; |
|
unsigned int off, clu = 0; |
|
struct exfat_sb_info *sbi = EXFAT_SB(sb); |
|
|
|
off = EXFAT_DEN_TO_B(entry); |
|
|
|
ret = exfat_walk_fat_chain(sb, p_dir, off, &clu); |
|
if (ret) |
|
return ret; |
|
|
|
/* byte offset in cluster */ |
|
off = EXFAT_CLU_OFFSET(off, sbi); |
|
|
|
/* byte offset in sector */ |
|
*offset = EXFAT_BLK_OFFSET(off, sb); |
|
|
|
/* sector offset in cluster */ |
|
*sector = EXFAT_B_TO_BLK(off, sb); |
|
*sector += exfat_cluster_to_sector(sbi, clu); |
|
return 0; |
|
} |
|
|
|
#define EXFAT_MAX_RA_SIZE (128*1024) |
|
static int exfat_dir_readahead(struct super_block *sb, sector_t sec) |
|
{ |
|
struct exfat_sb_info *sbi = EXFAT_SB(sb); |
|
struct buffer_head *bh; |
|
unsigned int max_ra_count = EXFAT_MAX_RA_SIZE >> sb->s_blocksize_bits; |
|
unsigned int page_ra_count = PAGE_SIZE >> sb->s_blocksize_bits; |
|
unsigned int adj_ra_count = max(sbi->sect_per_clus, page_ra_count); |
|
unsigned int ra_count = min(adj_ra_count, max_ra_count); |
|
|
|
/* Read-ahead is not required */ |
|
if (sbi->sect_per_clus == 1) |
|
return 0; |
|
|
|
if (sec < sbi->data_start_sector) { |
|
exfat_err(sb, "requested sector is invalid(sect:%llu, root:%llu)", |
|
(unsigned long long)sec, sbi->data_start_sector); |
|
return -EIO; |
|
} |
|
|
|
/* Not sector aligned with ra_count, resize ra_count to page size */ |
|
if ((sec - sbi->data_start_sector) & (ra_count - 1)) |
|
ra_count = page_ra_count; |
|
|
|
bh = sb_find_get_block(sb, sec); |
|
if (!bh || !buffer_uptodate(bh)) { |
|
unsigned int i; |
|
|
|
for (i = 0; i < ra_count; i++) |
|
sb_breadahead(sb, (sector_t)(sec + i)); |
|
} |
|
brelse(bh); |
|
return 0; |
|
} |
|
|
|
struct exfat_dentry *exfat_get_dentry(struct super_block *sb, |
|
struct exfat_chain *p_dir, int entry, struct buffer_head **bh, |
|
sector_t *sector) |
|
{ |
|
unsigned int dentries_per_page = EXFAT_B_TO_DEN(PAGE_SIZE); |
|
int off; |
|
sector_t sec; |
|
|
|
if (p_dir->dir == DIR_DELETED) { |
|
exfat_err(sb, "abnormal access to deleted dentry"); |
|
return NULL; |
|
} |
|
|
|
if (exfat_find_location(sb, p_dir, entry, &sec, &off)) |
|
return NULL; |
|
|
|
if (p_dir->dir != EXFAT_FREE_CLUSTER && |
|
!(entry & (dentries_per_page - 1))) |
|
exfat_dir_readahead(sb, sec); |
|
|
|
*bh = sb_bread(sb, sec); |
|
if (!*bh) |
|
return NULL; |
|
|
|
if (sector) |
|
*sector = sec; |
|
return (struct exfat_dentry *)((*bh)->b_data + off); |
|
} |
|
|
|
enum exfat_validate_dentry_mode { |
|
ES_MODE_STARTED, |
|
ES_MODE_GET_FILE_ENTRY, |
|
ES_MODE_GET_STRM_ENTRY, |
|
ES_MODE_GET_NAME_ENTRY, |
|
ES_MODE_GET_CRITICAL_SEC_ENTRY, |
|
}; |
|
|
|
static bool exfat_validate_entry(unsigned int type, |
|
enum exfat_validate_dentry_mode *mode) |
|
{ |
|
if (type == TYPE_UNUSED || type == TYPE_DELETED) |
|
return false; |
|
|
|
switch (*mode) { |
|
case ES_MODE_STARTED: |
|
if (type != TYPE_FILE && type != TYPE_DIR) |
|
return false; |
|
*mode = ES_MODE_GET_FILE_ENTRY; |
|
return true; |
|
case ES_MODE_GET_FILE_ENTRY: |
|
if (type != TYPE_STREAM) |
|
return false; |
|
*mode = ES_MODE_GET_STRM_ENTRY; |
|
return true; |
|
case ES_MODE_GET_STRM_ENTRY: |
|
if (type != TYPE_EXTEND) |
|
return false; |
|
*mode = ES_MODE_GET_NAME_ENTRY; |
|
return true; |
|
case ES_MODE_GET_NAME_ENTRY: |
|
if (type == TYPE_STREAM) |
|
return false; |
|
if (type != TYPE_EXTEND) { |
|
if (!(type & TYPE_CRITICAL_SEC)) |
|
return false; |
|
*mode = ES_MODE_GET_CRITICAL_SEC_ENTRY; |
|
} |
|
return true; |
|
case ES_MODE_GET_CRITICAL_SEC_ENTRY: |
|
if (type == TYPE_EXTEND || type == TYPE_STREAM) |
|
return false; |
|
if ((type & TYPE_CRITICAL_SEC) != TYPE_CRITICAL_SEC) |
|
return false; |
|
return true; |
|
default: |
|
WARN_ON_ONCE(1); |
|
return false; |
|
} |
|
} |
|
|
|
struct exfat_dentry *exfat_get_dentry_cached( |
|
struct exfat_entry_set_cache *es, int num) |
|
{ |
|
int off = es->start_off + num * DENTRY_SIZE; |
|
struct buffer_head *bh = es->bh[EXFAT_B_TO_BLK(off, es->sb)]; |
|
char *p = bh->b_data + EXFAT_BLK_OFFSET(off, es->sb); |
|
|
|
return (struct exfat_dentry *)p; |
|
} |
|
|
|
/* |
|
* Returns a set of dentries for a file or dir. |
|
* |
|
* Note It provides a direct pointer to bh->data via exfat_get_dentry_cached(). |
|
* User should call exfat_get_dentry_set() after setting 'modified' to apply |
|
* changes made in this entry set to the real device. |
|
* |
|
* in: |
|
* sb+p_dir+entry: indicates a file/dir |
|
* type: specifies how many dentries should be included. |
|
* return: |
|
* pointer of entry set on success, |
|
* NULL on failure. |
|
*/ |
|
struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb, |
|
struct exfat_chain *p_dir, int entry, unsigned int type) |
|
{ |
|
int ret, i, num_bh; |
|
unsigned int off, byte_offset, clu = 0; |
|
sector_t sec; |
|
struct exfat_sb_info *sbi = EXFAT_SB(sb); |
|
struct exfat_entry_set_cache *es; |
|
struct exfat_dentry *ep; |
|
int num_entries; |
|
enum exfat_validate_dentry_mode mode = ES_MODE_STARTED; |
|
struct buffer_head *bh; |
|
|
|
if (p_dir->dir == DIR_DELETED) { |
|
exfat_err(sb, "access to deleted dentry"); |
|
return NULL; |
|
} |
|
|
|
byte_offset = EXFAT_DEN_TO_B(entry); |
|
ret = exfat_walk_fat_chain(sb, p_dir, byte_offset, &clu); |
|
if (ret) |
|
return NULL; |
|
|
|
es = kzalloc(sizeof(*es), GFP_KERNEL); |
|
if (!es) |
|
return NULL; |
|
es->sb = sb; |
|
es->modified = false; |
|
|
|
/* byte offset in cluster */ |
|
byte_offset = EXFAT_CLU_OFFSET(byte_offset, sbi); |
|
|
|
/* byte offset in sector */ |
|
off = EXFAT_BLK_OFFSET(byte_offset, sb); |
|
es->start_off = off; |
|
|
|
/* sector offset in cluster */ |
|
sec = EXFAT_B_TO_BLK(byte_offset, sb); |
|
sec += exfat_cluster_to_sector(sbi, clu); |
|
|
|
bh = sb_bread(sb, sec); |
|
if (!bh) |
|
goto free_es; |
|
es->bh[es->num_bh++] = bh; |
|
|
|
ep = exfat_get_dentry_cached(es, 0); |
|
if (!exfat_validate_entry(exfat_get_entry_type(ep), &mode)) |
|
goto free_es; |
|
|
|
num_entries = type == ES_ALL_ENTRIES ? |
|
ep->dentry.file.num_ext + 1 : type; |
|
es->num_entries = num_entries; |
|
|
|
num_bh = EXFAT_B_TO_BLK_ROUND_UP(off + num_entries * DENTRY_SIZE, sb); |
|
for (i = 1; i < num_bh; i++) { |
|
/* get the next sector */ |
|
if (exfat_is_last_sector_in_cluster(sbi, sec)) { |
|
if (p_dir->flags == ALLOC_NO_FAT_CHAIN) |
|
clu++; |
|
else if (exfat_get_next_cluster(sb, &clu)) |
|
goto free_es; |
|
sec = exfat_cluster_to_sector(sbi, clu); |
|
} else { |
|
sec++; |
|
} |
|
|
|
bh = sb_bread(sb, sec); |
|
if (!bh) |
|
goto free_es; |
|
es->bh[es->num_bh++] = bh; |
|
} |
|
|
|
/* validiate cached dentries */ |
|
for (i = 1; i < num_entries; i++) { |
|
ep = exfat_get_dentry_cached(es, i); |
|
if (!exfat_validate_entry(exfat_get_entry_type(ep), &mode)) |
|
goto free_es; |
|
} |
|
return es; |
|
|
|
free_es: |
|
exfat_free_dentry_set(es, false); |
|
return NULL; |
|
} |
|
|
|
enum { |
|
DIRENT_STEP_FILE, |
|
DIRENT_STEP_STRM, |
|
DIRENT_STEP_NAME, |
|
DIRENT_STEP_SECD, |
|
}; |
|
|
|
/* |
|
* @ei: inode info of parent directory |
|
* @p_dir: directory structure of parent directory |
|
* @num_entries:entry size of p_uniname |
|
* @hint_opt: If p_uniname is found, filled with optimized dir/entry |
|
* for traversing cluster chain. |
|
* @return: |
|
* >= 0: file directory entry position where the name exists |
|
* -ENOENT: entry with the name does not exist |
|
* -EIO: I/O error |
|
*/ |
|
int exfat_find_dir_entry(struct super_block *sb, struct exfat_inode_info *ei, |
|
struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname, |
|
int num_entries, unsigned int type, struct exfat_hint *hint_opt) |
|
{ |
|
int i, rewind = 0, dentry = 0, end_eidx = 0, num_ext = 0, len; |
|
int order, step, name_len = 0; |
|
int dentries_per_clu, num_empty = 0; |
|
unsigned int entry_type; |
|
unsigned short *uniname = NULL; |
|
struct exfat_chain clu; |
|
struct exfat_hint *hint_stat = &ei->hint_stat; |
|
struct exfat_hint_femp candi_empty; |
|
struct exfat_sb_info *sbi = EXFAT_SB(sb); |
|
|
|
dentries_per_clu = sbi->dentries_per_clu; |
|
|
|
exfat_chain_dup(&clu, p_dir); |
|
|
|
if (hint_stat->eidx) { |
|
clu.dir = hint_stat->clu; |
|
dentry = hint_stat->eidx; |
|
end_eidx = dentry; |
|
} |
|
|
|
candi_empty.eidx = EXFAT_HINT_NONE; |
|
rewind: |
|
order = 0; |
|
step = DIRENT_STEP_FILE; |
|
while (clu.dir != EXFAT_EOF_CLUSTER) { |
|
i = dentry & (dentries_per_clu - 1); |
|
for (; i < dentries_per_clu; i++, dentry++) { |
|
struct exfat_dentry *ep; |
|
struct buffer_head *bh; |
|
|
|
if (rewind && dentry == end_eidx) |
|
goto not_found; |
|
|
|
ep = exfat_get_dentry(sb, &clu, i, &bh, NULL); |
|
if (!ep) |
|
return -EIO; |
|
|
|
entry_type = exfat_get_entry_type(ep); |
|
|
|
if (entry_type == TYPE_UNUSED || |
|
entry_type == TYPE_DELETED) { |
|
step = DIRENT_STEP_FILE; |
|
|
|
num_empty++; |
|
if (candi_empty.eidx == EXFAT_HINT_NONE && |
|
num_empty == 1) { |
|
exfat_chain_set(&candi_empty.cur, |
|
clu.dir, clu.size, clu.flags); |
|
} |
|
|
|
if (candi_empty.eidx == EXFAT_HINT_NONE && |
|
num_empty >= num_entries) { |
|
candi_empty.eidx = |
|
dentry - (num_empty - 1); |
|
WARN_ON(candi_empty.eidx < 0); |
|
candi_empty.count = num_empty; |
|
|
|
if (ei->hint_femp.eidx == |
|
EXFAT_HINT_NONE || |
|
candi_empty.eidx <= |
|
ei->hint_femp.eidx) |
|
ei->hint_femp = candi_empty; |
|
} |
|
|
|
brelse(bh); |
|
if (entry_type == TYPE_UNUSED) |
|
goto not_found; |
|
continue; |
|
} |
|
|
|
num_empty = 0; |
|
candi_empty.eidx = EXFAT_HINT_NONE; |
|
|
|
if (entry_type == TYPE_FILE || entry_type == TYPE_DIR) { |
|
step = DIRENT_STEP_FILE; |
|
hint_opt->clu = clu.dir; |
|
hint_opt->eidx = i; |
|
if (type == TYPE_ALL || type == entry_type) { |
|
num_ext = ep->dentry.file.num_ext; |
|
step = DIRENT_STEP_STRM; |
|
} |
|
brelse(bh); |
|
continue; |
|
} |
|
|
|
if (entry_type == TYPE_STREAM) { |
|
u16 name_hash; |
|
|
|
if (step != DIRENT_STEP_STRM) { |
|
step = DIRENT_STEP_FILE; |
|
brelse(bh); |
|
continue; |
|
} |
|
step = DIRENT_STEP_FILE; |
|
name_hash = le16_to_cpu( |
|
ep->dentry.stream.name_hash); |
|
if (p_uniname->name_hash == name_hash && |
|
p_uniname->name_len == |
|
ep->dentry.stream.name_len) { |
|
step = DIRENT_STEP_NAME; |
|
order = 1; |
|
name_len = 0; |
|
} |
|
brelse(bh); |
|
continue; |
|
} |
|
|
|
brelse(bh); |
|
if (entry_type == TYPE_EXTEND) { |
|
unsigned short entry_uniname[16], unichar; |
|
|
|
if (step != DIRENT_STEP_NAME) { |
|
step = DIRENT_STEP_FILE; |
|
continue; |
|
} |
|
|
|
if (++order == 2) |
|
uniname = p_uniname->name; |
|
else |
|
uniname += EXFAT_FILE_NAME_LEN; |
|
|
|
len = exfat_extract_uni_name(ep, entry_uniname); |
|
name_len += len; |
|
|
|
unichar = *(uniname+len); |
|
*(uniname+len) = 0x0; |
|
|
|
if (exfat_uniname_ncmp(sb, uniname, |
|
entry_uniname, len)) { |
|
step = DIRENT_STEP_FILE; |
|
} else if (p_uniname->name_len == name_len) { |
|
if (order == num_ext) |
|
goto found; |
|
step = DIRENT_STEP_SECD; |
|
} |
|
|
|
*(uniname+len) = unichar; |
|
continue; |
|
} |
|
|
|
if (entry_type & |
|
(TYPE_CRITICAL_SEC | TYPE_BENIGN_SEC)) { |
|
if (step == DIRENT_STEP_SECD) { |
|
if (++order == num_ext) |
|
goto found; |
|
continue; |
|
} |
|
} |
|
step = DIRENT_STEP_FILE; |
|
} |
|
|
|
if (clu.flags == ALLOC_NO_FAT_CHAIN) { |
|
if (--clu.size > 0) |
|
clu.dir++; |
|
else |
|
clu.dir = EXFAT_EOF_CLUSTER; |
|
} else { |
|
if (exfat_get_next_cluster(sb, &clu.dir)) |
|
return -EIO; |
|
} |
|
} |
|
|
|
not_found: |
|
/* |
|
* We started at not 0 index,so we should try to find target |
|
* from 0 index to the index we started at. |
|
*/ |
|
if (!rewind && end_eidx) { |
|
rewind = 1; |
|
dentry = 0; |
|
clu.dir = p_dir->dir; |
|
/* reset empty hint */ |
|
num_empty = 0; |
|
candi_empty.eidx = EXFAT_HINT_NONE; |
|
goto rewind; |
|
} |
|
|
|
/* initialized hint_stat */ |
|
hint_stat->clu = p_dir->dir; |
|
hint_stat->eidx = 0; |
|
return -ENOENT; |
|
|
|
found: |
|
/* next dentry we'll find is out of this cluster */ |
|
if (!((dentry + 1) & (dentries_per_clu - 1))) { |
|
int ret = 0; |
|
|
|
if (clu.flags == ALLOC_NO_FAT_CHAIN) { |
|
if (--clu.size > 0) |
|
clu.dir++; |
|
else |
|
clu.dir = EXFAT_EOF_CLUSTER; |
|
} else { |
|
ret = exfat_get_next_cluster(sb, &clu.dir); |
|
} |
|
|
|
if (ret || clu.dir == EXFAT_EOF_CLUSTER) { |
|
/* just initialized hint_stat */ |
|
hint_stat->clu = p_dir->dir; |
|
hint_stat->eidx = 0; |
|
return (dentry - num_ext); |
|
} |
|
} |
|
|
|
hint_stat->clu = clu.dir; |
|
hint_stat->eidx = dentry + 1; |
|
return dentry - num_ext; |
|
} |
|
|
|
int exfat_count_ext_entries(struct super_block *sb, struct exfat_chain *p_dir, |
|
int entry, struct exfat_dentry *ep) |
|
{ |
|
int i, count = 0; |
|
unsigned int type; |
|
struct exfat_dentry *ext_ep; |
|
struct buffer_head *bh; |
|
|
|
for (i = 0, entry++; i < ep->dentry.file.num_ext; i++, entry++) { |
|
ext_ep = exfat_get_dentry(sb, p_dir, entry, &bh, NULL); |
|
if (!ext_ep) |
|
return -EIO; |
|
|
|
type = exfat_get_entry_type(ext_ep); |
|
brelse(bh); |
|
if (type == TYPE_EXTEND || type == TYPE_STREAM) |
|
count++; |
|
else |
|
break; |
|
} |
|
return count; |
|
} |
|
|
|
int exfat_count_dir_entries(struct super_block *sb, struct exfat_chain *p_dir) |
|
{ |
|
int i, count = 0; |
|
int dentries_per_clu; |
|
unsigned int entry_type; |
|
struct exfat_chain clu; |
|
struct exfat_dentry *ep; |
|
struct exfat_sb_info *sbi = EXFAT_SB(sb); |
|
struct buffer_head *bh; |
|
|
|
dentries_per_clu = sbi->dentries_per_clu; |
|
|
|
exfat_chain_dup(&clu, p_dir); |
|
|
|
while (clu.dir != EXFAT_EOF_CLUSTER) { |
|
for (i = 0; i < dentries_per_clu; i++) { |
|
ep = exfat_get_dentry(sb, &clu, i, &bh, NULL); |
|
if (!ep) |
|
return -EIO; |
|
entry_type = exfat_get_entry_type(ep); |
|
brelse(bh); |
|
|
|
if (entry_type == TYPE_UNUSED) |
|
return count; |
|
if (entry_type != TYPE_DIR) |
|
continue; |
|
count++; |
|
} |
|
|
|
if (clu.flags == ALLOC_NO_FAT_CHAIN) { |
|
if (--clu.size > 0) |
|
clu.dir++; |
|
else |
|
clu.dir = EXFAT_EOF_CLUSTER; |
|
} else { |
|
if (exfat_get_next_cluster(sb, &(clu.dir))) |
|
return -EIO; |
|
} |
|
} |
|
|
|
return count; |
|
}
|
|
|