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![Deepa Dinamani](/assets/img/avatar_default.png)
CURRENT_TIME_SEC is not y2038 safe. current_time() will be transitioned to use 64 bit time along with vfs in a separate patch. There is no plan to transistion CURRENT_TIME_SEC to use y2038 safe time interfaces. current_time() will also be extended to use superblock range checking parameters when range checking is introduced. This works because alloc_super() fills in the the s_time_gran in super block to NSEC_PER_SEC. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
1408 lines
35 KiB
C
1408 lines
35 KiB
C
/*
|
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* linux/fs/fat/dir.c
|
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*
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* directory handling functions for fat-based filesystems
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*
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* Written 1992,1993 by Werner Almesberger
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*
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* Hidden files 1995 by Albert Cahalan <albert@ccs.neu.edu> <adc@coe.neu.edu>
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*
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* VFAT extensions by Gordon Chaffee <chaffee@plateau.cs.berkeley.edu>
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* Merged with msdos fs by Henrik Storner <storner@osiris.ping.dk>
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* Rewritten for constant inumbers. Plugged buffer overrun in readdir(). AV
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* Short name translation 1999, 2001 by Wolfram Pienkoss <wp@bszh.de>
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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/uaccess.h>
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#include "fat.h"
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/*
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* Maximum buffer size of short name.
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* [(MSDOS_NAME + '.') * max one char + nul]
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* For msdos style, ['.' (hidden) + MSDOS_NAME + '.' + nul]
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*/
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#define FAT_MAX_SHORT_SIZE ((MSDOS_NAME + 1) * NLS_MAX_CHARSET_SIZE + 1)
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/*
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* Maximum buffer size of unicode chars from slots.
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* [(max longname slots * 13 (size in a slot) + nul) * sizeof(wchar_t)]
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*/
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#define FAT_MAX_UNI_CHARS ((MSDOS_SLOTS - 1) * 13 + 1)
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#define FAT_MAX_UNI_SIZE (FAT_MAX_UNI_CHARS * sizeof(wchar_t))
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static inline unsigned char fat_tolower(unsigned char c)
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{
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return ((c >= 'A') && (c <= 'Z')) ? c+32 : c;
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}
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static inline loff_t fat_make_i_pos(struct super_block *sb,
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struct buffer_head *bh,
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struct msdos_dir_entry *de)
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{
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return ((loff_t)bh->b_blocknr << MSDOS_SB(sb)->dir_per_block_bits)
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| (de - (struct msdos_dir_entry *)bh->b_data);
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}
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static inline void fat_dir_readahead(struct inode *dir, sector_t iblock,
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sector_t phys)
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{
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struct super_block *sb = dir->i_sb;
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struct msdos_sb_info *sbi = MSDOS_SB(sb);
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struct buffer_head *bh;
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int sec;
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/* This is not a first sector of cluster, or sec_per_clus == 1 */
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if ((iblock & (sbi->sec_per_clus - 1)) || sbi->sec_per_clus == 1)
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return;
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/* root dir of FAT12/FAT16 */
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if ((sbi->fat_bits != 32) && (dir->i_ino == MSDOS_ROOT_INO))
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return;
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bh = sb_find_get_block(sb, phys);
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if (bh == NULL || !buffer_uptodate(bh)) {
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for (sec = 0; sec < sbi->sec_per_clus; sec++)
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sb_breadahead(sb, phys + sec);
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}
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brelse(bh);
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}
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/* Returns the inode number of the directory entry at offset pos. If bh is
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non-NULL, it is brelse'd before. Pos is incremented. The buffer header is
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returned in bh.
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AV. Most often we do it item-by-item. Makes sense to optimize.
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AV. OK, there we go: if both bh and de are non-NULL we assume that we just
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AV. want the next entry (took one explicit de=NULL in vfat/namei.c).
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AV. It's done in fat_get_entry() (inlined), here the slow case lives.
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AV. Additionally, when we return -1 (i.e. reached the end of directory)
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AV. we make bh NULL.
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*/
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static int fat__get_entry(struct inode *dir, loff_t *pos,
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struct buffer_head **bh, struct msdos_dir_entry **de)
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{
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struct super_block *sb = dir->i_sb;
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sector_t phys, iblock;
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unsigned long mapped_blocks;
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int err, offset;
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next:
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if (*bh)
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brelse(*bh);
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*bh = NULL;
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iblock = *pos >> sb->s_blocksize_bits;
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err = fat_bmap(dir, iblock, &phys, &mapped_blocks, 0, false);
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if (err || !phys)
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return -1; /* beyond EOF or error */
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fat_dir_readahead(dir, iblock, phys);
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*bh = sb_bread(sb, phys);
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if (*bh == NULL) {
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fat_msg_ratelimit(sb, KERN_ERR,
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"Directory bread(block %llu) failed", (llu)phys);
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/* skip this block */
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*pos = (iblock + 1) << sb->s_blocksize_bits;
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goto next;
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}
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offset = *pos & (sb->s_blocksize - 1);
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*pos += sizeof(struct msdos_dir_entry);
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*de = (struct msdos_dir_entry *)((*bh)->b_data + offset);
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return 0;
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}
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static inline int fat_get_entry(struct inode *dir, loff_t *pos,
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struct buffer_head **bh,
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struct msdos_dir_entry **de)
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{
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/* Fast stuff first */
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if (*bh && *de &&
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(*de - (struct msdos_dir_entry *)(*bh)->b_data) <
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MSDOS_SB(dir->i_sb)->dir_per_block - 1) {
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*pos += sizeof(struct msdos_dir_entry);
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(*de)++;
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return 0;
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}
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return fat__get_entry(dir, pos, bh, de);
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}
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/*
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* Convert Unicode 16 to UTF-8, translated Unicode, or ASCII.
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* If uni_xlate is enabled and we can't get a 1:1 conversion, use a
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* colon as an escape character since it is normally invalid on the vfat
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* filesystem. The following four characters are the hexadecimal digits
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* of Unicode value. This lets us do a full dump and restore of Unicode
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* filenames. We could get into some trouble with long Unicode names,
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* but ignore that right now.
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* Ahem... Stack smashing in ring 0 isn't fun. Fixed.
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*/
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static int uni16_to_x8(struct super_block *sb, unsigned char *ascii,
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const wchar_t *uni, int len, struct nls_table *nls)
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{
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int uni_xlate = MSDOS_SB(sb)->options.unicode_xlate;
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const wchar_t *ip;
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wchar_t ec;
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unsigned char *op;
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int charlen;
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ip = uni;
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op = ascii;
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while (*ip && ((len - NLS_MAX_CHARSET_SIZE) > 0)) {
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ec = *ip++;
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charlen = nls->uni2char(ec, op, NLS_MAX_CHARSET_SIZE);
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if (charlen > 0) {
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op += charlen;
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len -= charlen;
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} else {
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if (uni_xlate == 1) {
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*op++ = ':';
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op = hex_byte_pack(op, ec >> 8);
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op = hex_byte_pack(op, ec);
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len -= 5;
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} else {
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*op++ = '?';
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len--;
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}
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}
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}
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if (unlikely(*ip)) {
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fat_msg(sb, KERN_WARNING,
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"filename was truncated while converting.");
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}
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*op = 0;
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return op - ascii;
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}
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static inline int fat_uni_to_x8(struct super_block *sb, const wchar_t *uni,
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unsigned char *buf, int size)
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{
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struct msdos_sb_info *sbi = MSDOS_SB(sb);
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if (sbi->options.utf8)
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return utf16s_to_utf8s(uni, FAT_MAX_UNI_CHARS,
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UTF16_HOST_ENDIAN, buf, size);
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else
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return uni16_to_x8(sb, buf, uni, size, sbi->nls_io);
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}
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static inline int
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fat_short2uni(struct nls_table *t, unsigned char *c, int clen, wchar_t *uni)
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{
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int charlen;
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charlen = t->char2uni(c, clen, uni);
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if (charlen < 0) {
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*uni = 0x003f; /* a question mark */
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charlen = 1;
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}
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return charlen;
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}
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static inline int
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fat_short2lower_uni(struct nls_table *t, unsigned char *c,
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int clen, wchar_t *uni)
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{
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int charlen;
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wchar_t wc;
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charlen = t->char2uni(c, clen, &wc);
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if (charlen < 0) {
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*uni = 0x003f; /* a question mark */
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charlen = 1;
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} else if (charlen <= 1) {
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unsigned char nc = t->charset2lower[*c];
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if (!nc)
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nc = *c;
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charlen = t->char2uni(&nc, 1, uni);
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if (charlen < 0) {
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*uni = 0x003f; /* a question mark */
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charlen = 1;
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}
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} else
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*uni = wc;
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return charlen;
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}
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static inline int
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fat_shortname2uni(struct nls_table *nls, unsigned char *buf, int buf_size,
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wchar_t *uni_buf, unsigned short opt, int lower)
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{
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int len = 0;
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if (opt & VFAT_SFN_DISPLAY_LOWER)
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len = fat_short2lower_uni(nls, buf, buf_size, uni_buf);
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else if (opt & VFAT_SFN_DISPLAY_WIN95)
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len = fat_short2uni(nls, buf, buf_size, uni_buf);
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else if (opt & VFAT_SFN_DISPLAY_WINNT) {
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if (lower)
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len = fat_short2lower_uni(nls, buf, buf_size, uni_buf);
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else
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len = fat_short2uni(nls, buf, buf_size, uni_buf);
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} else
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len = fat_short2uni(nls, buf, buf_size, uni_buf);
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return len;
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}
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static inline int fat_name_match(struct msdos_sb_info *sbi,
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const unsigned char *a, int a_len,
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const unsigned char *b, int b_len)
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{
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if (a_len != b_len)
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return 0;
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if (sbi->options.name_check != 's')
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return !nls_strnicmp(sbi->nls_io, a, b, a_len);
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else
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return !memcmp(a, b, a_len);
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}
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enum { PARSE_INVALID = 1, PARSE_NOT_LONGNAME, PARSE_EOF, };
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/**
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* fat_parse_long - Parse extended directory entry.
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*
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* This function returns zero on success, negative value on error, or one of
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* the following:
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*
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* %PARSE_INVALID - Directory entry is invalid.
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* %PARSE_NOT_LONGNAME - Directory entry does not contain longname.
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* %PARSE_EOF - Directory has no more entries.
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*/
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static int fat_parse_long(struct inode *dir, loff_t *pos,
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struct buffer_head **bh, struct msdos_dir_entry **de,
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wchar_t **unicode, unsigned char *nr_slots)
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{
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struct msdos_dir_slot *ds;
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unsigned char id, slot, slots, alias_checksum;
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if (!*unicode) {
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*unicode = __getname();
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if (!*unicode) {
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brelse(*bh);
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return -ENOMEM;
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}
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}
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parse_long:
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slots = 0;
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ds = (struct msdos_dir_slot *)*de;
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id = ds->id;
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if (!(id & 0x40))
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return PARSE_INVALID;
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slots = id & ~0x40;
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if (slots > 20 || !slots) /* ceil(256 * 2 / 26) */
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return PARSE_INVALID;
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*nr_slots = slots;
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alias_checksum = ds->alias_checksum;
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slot = slots;
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while (1) {
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int offset;
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slot--;
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offset = slot * 13;
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fat16_towchar(*unicode + offset, ds->name0_4, 5);
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fat16_towchar(*unicode + offset + 5, ds->name5_10, 6);
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fat16_towchar(*unicode + offset + 11, ds->name11_12, 2);
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|
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if (ds->id & 0x40)
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(*unicode)[offset + 13] = 0;
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if (fat_get_entry(dir, pos, bh, de) < 0)
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return PARSE_EOF;
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if (slot == 0)
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break;
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ds = (struct msdos_dir_slot *)*de;
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if (ds->attr != ATTR_EXT)
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return PARSE_NOT_LONGNAME;
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if ((ds->id & ~0x40) != slot)
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goto parse_long;
|
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if (ds->alias_checksum != alias_checksum)
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goto parse_long;
|
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}
|
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if ((*de)->name[0] == DELETED_FLAG)
|
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return PARSE_INVALID;
|
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if ((*de)->attr == ATTR_EXT)
|
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goto parse_long;
|
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if (IS_FREE((*de)->name) || ((*de)->attr & ATTR_VOLUME))
|
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return PARSE_INVALID;
|
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if (fat_checksum((*de)->name) != alias_checksum)
|
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*nr_slots = 0;
|
|
|
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return 0;
|
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}
|
|
|
|
/**
|
|
* fat_parse_short - Parse MS-DOS (short) directory entry.
|
|
* @sb: superblock
|
|
* @de: directory entry to parse
|
|
* @name: FAT_MAX_SHORT_SIZE array in which to place extracted name
|
|
* @dot_hidden: Nonzero == prepend '.' to names with ATTR_HIDDEN
|
|
*
|
|
* Returns the number of characters extracted into 'name'.
|
|
*/
|
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static int fat_parse_short(struct super_block *sb,
|
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const struct msdos_dir_entry *de,
|
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unsigned char *name, int dot_hidden)
|
|
{
|
|
const struct msdos_sb_info *sbi = MSDOS_SB(sb);
|
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int isvfat = sbi->options.isvfat;
|
|
int nocase = sbi->options.nocase;
|
|
unsigned short opt_shortname = sbi->options.shortname;
|
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struct nls_table *nls_disk = sbi->nls_disk;
|
|
wchar_t uni_name[14];
|
|
unsigned char c, work[MSDOS_NAME];
|
|
unsigned char *ptname = name;
|
|
int chi, chl, i, j, k;
|
|
int dotoffset = 0;
|
|
int name_len = 0, uni_len = 0;
|
|
|
|
if (!isvfat && dot_hidden && (de->attr & ATTR_HIDDEN)) {
|
|
*ptname++ = '.';
|
|
dotoffset = 1;
|
|
}
|
|
|
|
memcpy(work, de->name, sizeof(work));
|
|
/* see namei.c, msdos_format_name */
|
|
if (work[0] == 0x05)
|
|
work[0] = 0xE5;
|
|
|
|
/* Filename */
|
|
for (i = 0, j = 0; i < 8;) {
|
|
c = work[i];
|
|
if (!c)
|
|
break;
|
|
chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
|
|
&uni_name[j++], opt_shortname,
|
|
de->lcase & CASE_LOWER_BASE);
|
|
if (chl <= 1) {
|
|
if (!isvfat)
|
|
ptname[i] = nocase ? c : fat_tolower(c);
|
|
i++;
|
|
if (c != ' ') {
|
|
name_len = i;
|
|
uni_len = j;
|
|
}
|
|
} else {
|
|
uni_len = j;
|
|
if (isvfat)
|
|
i += min(chl, 8-i);
|
|
else {
|
|
for (chi = 0; chi < chl && i < 8; chi++, i++)
|
|
ptname[i] = work[i];
|
|
}
|
|
if (chl)
|
|
name_len = i;
|
|
}
|
|
}
|
|
|
|
i = name_len;
|
|
j = uni_len;
|
|
fat_short2uni(nls_disk, ".", 1, &uni_name[j++]);
|
|
if (!isvfat)
|
|
ptname[i] = '.';
|
|
i++;
|
|
|
|
/* Extension */
|
|
for (k = 8; k < MSDOS_NAME;) {
|
|
c = work[k];
|
|
if (!c)
|
|
break;
|
|
chl = fat_shortname2uni(nls_disk, &work[k], MSDOS_NAME - k,
|
|
&uni_name[j++], opt_shortname,
|
|
de->lcase & CASE_LOWER_EXT);
|
|
if (chl <= 1) {
|
|
k++;
|
|
if (!isvfat)
|
|
ptname[i] = nocase ? c : fat_tolower(c);
|
|
i++;
|
|
if (c != ' ') {
|
|
name_len = i;
|
|
uni_len = j;
|
|
}
|
|
} else {
|
|
uni_len = j;
|
|
if (isvfat) {
|
|
int offset = min(chl, MSDOS_NAME-k);
|
|
k += offset;
|
|
i += offset;
|
|
} else {
|
|
for (chi = 0; chi < chl && k < MSDOS_NAME;
|
|
chi++, i++, k++) {
|
|
ptname[i] = work[k];
|
|
}
|
|
}
|
|
if (chl)
|
|
name_len = i;
|
|
}
|
|
}
|
|
|
|
if (name_len > 0) {
|
|
name_len += dotoffset;
|
|
|
|
if (sbi->options.isvfat) {
|
|
uni_name[uni_len] = 0x0000;
|
|
name_len = fat_uni_to_x8(sb, uni_name, name,
|
|
FAT_MAX_SHORT_SIZE);
|
|
}
|
|
}
|
|
|
|
return name_len;
|
|
}
|
|
|
|
/*
|
|
* Return values: negative -> error/not found, 0 -> found.
|
|
*/
|
|
int fat_search_long(struct inode *inode, const unsigned char *name,
|
|
int name_len, struct fat_slot_info *sinfo)
|
|
{
|
|
struct super_block *sb = inode->i_sb;
|
|
struct msdos_sb_info *sbi = MSDOS_SB(sb);
|
|
struct buffer_head *bh = NULL;
|
|
struct msdos_dir_entry *de;
|
|
unsigned char nr_slots;
|
|
wchar_t *unicode = NULL;
|
|
unsigned char bufname[FAT_MAX_SHORT_SIZE];
|
|
loff_t cpos = 0;
|
|
int err, len;
|
|
|
|
err = -ENOENT;
|
|
while (1) {
|
|
if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
|
|
goto end_of_dir;
|
|
parse_record:
|
|
nr_slots = 0;
|
|
if (de->name[0] == DELETED_FLAG)
|
|
continue;
|
|
if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME))
|
|
continue;
|
|
if (de->attr != ATTR_EXT && IS_FREE(de->name))
|
|
continue;
|
|
if (de->attr == ATTR_EXT) {
|
|
int status = fat_parse_long(inode, &cpos, &bh, &de,
|
|
&unicode, &nr_slots);
|
|
if (status < 0) {
|
|
err = status;
|
|
goto end_of_dir;
|
|
} else if (status == PARSE_INVALID)
|
|
continue;
|
|
else if (status == PARSE_NOT_LONGNAME)
|
|
goto parse_record;
|
|
else if (status == PARSE_EOF)
|
|
goto end_of_dir;
|
|
}
|
|
|
|
/* Never prepend '.' to hidden files here.
|
|
* That is done only for msdos mounts (and only when
|
|
* 'dotsOK=yes'); if we are executing here, it is in the
|
|
* context of a vfat mount.
|
|
*/
|
|
len = fat_parse_short(sb, de, bufname, 0);
|
|
if (len == 0)
|
|
continue;
|
|
|
|
/* Compare shortname */
|
|
if (fat_name_match(sbi, name, name_len, bufname, len))
|
|
goto found;
|
|
|
|
if (nr_slots) {
|
|
void *longname = unicode + FAT_MAX_UNI_CHARS;
|
|
int size = PATH_MAX - FAT_MAX_UNI_SIZE;
|
|
|
|
/* Compare longname */
|
|
len = fat_uni_to_x8(sb, unicode, longname, size);
|
|
if (fat_name_match(sbi, name, name_len, longname, len))
|
|
goto found;
|
|
}
|
|
}
|
|
|
|
found:
|
|
nr_slots++; /* include the de */
|
|
sinfo->slot_off = cpos - nr_slots * sizeof(*de);
|
|
sinfo->nr_slots = nr_slots;
|
|
sinfo->de = de;
|
|
sinfo->bh = bh;
|
|
sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
|
|
err = 0;
|
|
end_of_dir:
|
|
if (unicode)
|
|
__putname(unicode);
|
|
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fat_search_long);
|
|
|
|
struct fat_ioctl_filldir_callback {
|
|
struct dir_context ctx;
|
|
void __user *dirent;
|
|
int result;
|
|
/* for dir ioctl */
|
|
const char *longname;
|
|
int long_len;
|
|
const char *shortname;
|
|
int short_len;
|
|
};
|
|
|
|
static int __fat_readdir(struct inode *inode, struct file *file,
|
|
struct dir_context *ctx, int short_only,
|
|
struct fat_ioctl_filldir_callback *both)
|
|
{
|
|
struct super_block *sb = inode->i_sb;
|
|
struct msdos_sb_info *sbi = MSDOS_SB(sb);
|
|
struct buffer_head *bh;
|
|
struct msdos_dir_entry *de;
|
|
unsigned char nr_slots;
|
|
wchar_t *unicode = NULL;
|
|
unsigned char bufname[FAT_MAX_SHORT_SIZE];
|
|
int isvfat = sbi->options.isvfat;
|
|
const char *fill_name = NULL;
|
|
int fake_offset = 0;
|
|
loff_t cpos;
|
|
int short_len = 0, fill_len = 0;
|
|
int ret = 0;
|
|
|
|
mutex_lock(&sbi->s_lock);
|
|
|
|
cpos = ctx->pos;
|
|
/* Fake . and .. for the root directory. */
|
|
if (inode->i_ino == MSDOS_ROOT_INO) {
|
|
if (!dir_emit_dots(file, ctx))
|
|
goto out;
|
|
if (ctx->pos == 2) {
|
|
fake_offset = 1;
|
|
cpos = 0;
|
|
}
|
|
}
|
|
if (cpos & (sizeof(struct msdos_dir_entry) - 1)) {
|
|
ret = -ENOENT;
|
|
goto out;
|
|
}
|
|
|
|
bh = NULL;
|
|
get_new:
|
|
if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
|
|
goto end_of_dir;
|
|
parse_record:
|
|
nr_slots = 0;
|
|
/*
|
|
* Check for long filename entry, but if short_only, we don't
|
|
* need to parse long filename.
|
|
*/
|
|
if (isvfat && !short_only) {
|
|
if (de->name[0] == DELETED_FLAG)
|
|
goto record_end;
|
|
if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME))
|
|
goto record_end;
|
|
if (de->attr != ATTR_EXT && IS_FREE(de->name))
|
|
goto record_end;
|
|
} else {
|
|
if ((de->attr & ATTR_VOLUME) || IS_FREE(de->name))
|
|
goto record_end;
|
|
}
|
|
|
|
if (isvfat && de->attr == ATTR_EXT) {
|
|
int status = fat_parse_long(inode, &cpos, &bh, &de,
|
|
&unicode, &nr_slots);
|
|
if (status < 0) {
|
|
bh = NULL;
|
|
ret = status;
|
|
goto end_of_dir;
|
|
} else if (status == PARSE_INVALID)
|
|
goto record_end;
|
|
else if (status == PARSE_NOT_LONGNAME)
|
|
goto parse_record;
|
|
else if (status == PARSE_EOF)
|
|
goto end_of_dir;
|
|
|
|
if (nr_slots) {
|
|
void *longname = unicode + FAT_MAX_UNI_CHARS;
|
|
int size = PATH_MAX - FAT_MAX_UNI_SIZE;
|
|
int len = fat_uni_to_x8(sb, unicode, longname, size);
|
|
|
|
fill_name = longname;
|
|
fill_len = len;
|
|
/* !both && !short_only, so we don't need shortname. */
|
|
if (!both)
|
|
goto start_filldir;
|
|
|
|
short_len = fat_parse_short(sb, de, bufname,
|
|
sbi->options.dotsOK);
|
|
if (short_len == 0)
|
|
goto record_end;
|
|
/* hack for fat_ioctl_filldir() */
|
|
both->longname = fill_name;
|
|
both->long_len = fill_len;
|
|
both->shortname = bufname;
|
|
both->short_len = short_len;
|
|
fill_name = NULL;
|
|
fill_len = 0;
|
|
goto start_filldir;
|
|
}
|
|
}
|
|
|
|
short_len = fat_parse_short(sb, de, bufname, sbi->options.dotsOK);
|
|
if (short_len == 0)
|
|
goto record_end;
|
|
|
|
fill_name = bufname;
|
|
fill_len = short_len;
|
|
|
|
start_filldir:
|
|
ctx->pos = cpos - (nr_slots + 1) * sizeof(struct msdos_dir_entry);
|
|
if (fake_offset && ctx->pos < 2)
|
|
ctx->pos = 2;
|
|
|
|
if (!memcmp(de->name, MSDOS_DOT, MSDOS_NAME)) {
|
|
if (!dir_emit_dot(file, ctx))
|
|
goto fill_failed;
|
|
} else if (!memcmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) {
|
|
if (!dir_emit_dotdot(file, ctx))
|
|
goto fill_failed;
|
|
} else {
|
|
unsigned long inum;
|
|
loff_t i_pos = fat_make_i_pos(sb, bh, de);
|
|
struct inode *tmp = fat_iget(sb, i_pos);
|
|
if (tmp) {
|
|
inum = tmp->i_ino;
|
|
iput(tmp);
|
|
} else
|
|
inum = iunique(sb, MSDOS_ROOT_INO);
|
|
if (!dir_emit(ctx, fill_name, fill_len, inum,
|
|
(de->attr & ATTR_DIR) ? DT_DIR : DT_REG))
|
|
goto fill_failed;
|
|
}
|
|
|
|
record_end:
|
|
fake_offset = 0;
|
|
ctx->pos = cpos;
|
|
goto get_new;
|
|
|
|
end_of_dir:
|
|
if (fake_offset && cpos < 2)
|
|
ctx->pos = 2;
|
|
else
|
|
ctx->pos = cpos;
|
|
fill_failed:
|
|
brelse(bh);
|
|
if (unicode)
|
|
__putname(unicode);
|
|
out:
|
|
mutex_unlock(&sbi->s_lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int fat_readdir(struct file *file, struct dir_context *ctx)
|
|
{
|
|
return __fat_readdir(file_inode(file), file, ctx, 0, NULL);
|
|
}
|
|
|
|
#define FAT_IOCTL_FILLDIR_FUNC(func, dirent_type) \
|
|
static int func(struct dir_context *ctx, const char *name, int name_len, \
|
|
loff_t offset, u64 ino, unsigned int d_type) \
|
|
{ \
|
|
struct fat_ioctl_filldir_callback *buf = \
|
|
container_of(ctx, struct fat_ioctl_filldir_callback, ctx); \
|
|
struct dirent_type __user *d1 = buf->dirent; \
|
|
struct dirent_type __user *d2 = d1 + 1; \
|
|
\
|
|
if (buf->result) \
|
|
return -EINVAL; \
|
|
buf->result++; \
|
|
\
|
|
if (name != NULL) { \
|
|
/* dirent has only short name */ \
|
|
if (name_len >= sizeof(d1->d_name)) \
|
|
name_len = sizeof(d1->d_name) - 1; \
|
|
\
|
|
if (put_user(0, d2->d_name) || \
|
|
put_user(0, &d2->d_reclen) || \
|
|
copy_to_user(d1->d_name, name, name_len) || \
|
|
put_user(0, d1->d_name + name_len) || \
|
|
put_user(name_len, &d1->d_reclen)) \
|
|
goto efault; \
|
|
} else { \
|
|
/* dirent has short and long name */ \
|
|
const char *longname = buf->longname; \
|
|
int long_len = buf->long_len; \
|
|
const char *shortname = buf->shortname; \
|
|
int short_len = buf->short_len; \
|
|
\
|
|
if (long_len >= sizeof(d1->d_name)) \
|
|
long_len = sizeof(d1->d_name) - 1; \
|
|
if (short_len >= sizeof(d1->d_name)) \
|
|
short_len = sizeof(d1->d_name) - 1; \
|
|
\
|
|
if (copy_to_user(d2->d_name, longname, long_len) || \
|
|
put_user(0, d2->d_name + long_len) || \
|
|
put_user(long_len, &d2->d_reclen) || \
|
|
put_user(ino, &d2->d_ino) || \
|
|
put_user(offset, &d2->d_off) || \
|
|
copy_to_user(d1->d_name, shortname, short_len) || \
|
|
put_user(0, d1->d_name + short_len) || \
|
|
put_user(short_len, &d1->d_reclen)) \
|
|
goto efault; \
|
|
} \
|
|
return 0; \
|
|
efault: \
|
|
buf->result = -EFAULT; \
|
|
return -EFAULT; \
|
|
}
|
|
|
|
FAT_IOCTL_FILLDIR_FUNC(fat_ioctl_filldir, __fat_dirent)
|
|
|
|
static int fat_ioctl_readdir(struct inode *inode, struct file *file,
|
|
void __user *dirent, filldir_t filldir,
|
|
int short_only, int both)
|
|
{
|
|
struct fat_ioctl_filldir_callback buf = {
|
|
.ctx.actor = filldir,
|
|
.dirent = dirent
|
|
};
|
|
int ret;
|
|
|
|
buf.dirent = dirent;
|
|
buf.result = 0;
|
|
inode_lock_shared(inode);
|
|
buf.ctx.pos = file->f_pos;
|
|
ret = -ENOENT;
|
|
if (!IS_DEADDIR(inode)) {
|
|
ret = __fat_readdir(inode, file, &buf.ctx,
|
|
short_only, both ? &buf : NULL);
|
|
file->f_pos = buf.ctx.pos;
|
|
}
|
|
inode_unlock_shared(inode);
|
|
if (ret >= 0)
|
|
ret = buf.result;
|
|
return ret;
|
|
}
|
|
|
|
static long fat_dir_ioctl(struct file *filp, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
struct inode *inode = file_inode(filp);
|
|
struct __fat_dirent __user *d1 = (struct __fat_dirent __user *)arg;
|
|
int short_only, both;
|
|
|
|
switch (cmd) {
|
|
case VFAT_IOCTL_READDIR_SHORT:
|
|
short_only = 1;
|
|
both = 0;
|
|
break;
|
|
case VFAT_IOCTL_READDIR_BOTH:
|
|
short_only = 0;
|
|
both = 1;
|
|
break;
|
|
default:
|
|
return fat_generic_ioctl(filp, cmd, arg);
|
|
}
|
|
|
|
if (!access_ok(VERIFY_WRITE, d1, sizeof(struct __fat_dirent[2])))
|
|
return -EFAULT;
|
|
/*
|
|
* Yes, we don't need this put_user() absolutely. However old
|
|
* code didn't return the right value. So, app use this value,
|
|
* in order to check whether it is EOF.
|
|
*/
|
|
if (put_user(0, &d1->d_reclen))
|
|
return -EFAULT;
|
|
|
|
return fat_ioctl_readdir(inode, filp, d1, fat_ioctl_filldir,
|
|
short_only, both);
|
|
}
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
#define VFAT_IOCTL_READDIR_BOTH32 _IOR('r', 1, struct compat_dirent[2])
|
|
#define VFAT_IOCTL_READDIR_SHORT32 _IOR('r', 2, struct compat_dirent[2])
|
|
|
|
FAT_IOCTL_FILLDIR_FUNC(fat_compat_ioctl_filldir, compat_dirent)
|
|
|
|
static long fat_compat_dir_ioctl(struct file *filp, unsigned cmd,
|
|
unsigned long arg)
|
|
{
|
|
struct inode *inode = file_inode(filp);
|
|
struct compat_dirent __user *d1 = compat_ptr(arg);
|
|
int short_only, both;
|
|
|
|
switch (cmd) {
|
|
case VFAT_IOCTL_READDIR_SHORT32:
|
|
short_only = 1;
|
|
both = 0;
|
|
break;
|
|
case VFAT_IOCTL_READDIR_BOTH32:
|
|
short_only = 0;
|
|
both = 1;
|
|
break;
|
|
default:
|
|
return fat_generic_ioctl(filp, cmd, (unsigned long)arg);
|
|
}
|
|
|
|
if (!access_ok(VERIFY_WRITE, d1, sizeof(struct compat_dirent[2])))
|
|
return -EFAULT;
|
|
/*
|
|
* Yes, we don't need this put_user() absolutely. However old
|
|
* code didn't return the right value. So, app use this value,
|
|
* in order to check whether it is EOF.
|
|
*/
|
|
if (put_user(0, &d1->d_reclen))
|
|
return -EFAULT;
|
|
|
|
return fat_ioctl_readdir(inode, filp, d1, fat_compat_ioctl_filldir,
|
|
short_only, both);
|
|
}
|
|
#endif /* CONFIG_COMPAT */
|
|
|
|
const struct file_operations fat_dir_operations = {
|
|
.llseek = generic_file_llseek,
|
|
.read = generic_read_dir,
|
|
.iterate_shared = fat_readdir,
|
|
.unlocked_ioctl = fat_dir_ioctl,
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_ioctl = fat_compat_dir_ioctl,
|
|
#endif
|
|
.fsync = fat_file_fsync,
|
|
};
|
|
|
|
static int fat_get_short_entry(struct inode *dir, loff_t *pos,
|
|
struct buffer_head **bh,
|
|
struct msdos_dir_entry **de)
|
|
{
|
|
while (fat_get_entry(dir, pos, bh, de) >= 0) {
|
|
/* free entry or long name entry or volume label */
|
|
if (!IS_FREE((*de)->name) && !((*de)->attr & ATTR_VOLUME))
|
|
return 0;
|
|
}
|
|
return -ENOENT;
|
|
}
|
|
|
|
/*
|
|
* The ".." entry can not provide the "struct fat_slot_info" information
|
|
* for inode, nor a usable i_pos. So, this function provides some information
|
|
* only.
|
|
*
|
|
* Since this function walks through the on-disk inodes within a directory,
|
|
* callers are responsible for taking any locks necessary to prevent the
|
|
* directory from changing.
|
|
*/
|
|
int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh,
|
|
struct msdos_dir_entry **de)
|
|
{
|
|
loff_t offset = 0;
|
|
|
|
*de = NULL;
|
|
while (fat_get_short_entry(dir, &offset, bh, de) >= 0) {
|
|
if (!strncmp((*de)->name, MSDOS_DOTDOT, MSDOS_NAME))
|
|
return 0;
|
|
}
|
|
return -ENOENT;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fat_get_dotdot_entry);
|
|
|
|
/* See if directory is empty */
|
|
int fat_dir_empty(struct inode *dir)
|
|
{
|
|
struct buffer_head *bh;
|
|
struct msdos_dir_entry *de;
|
|
loff_t cpos;
|
|
int result = 0;
|
|
|
|
bh = NULL;
|
|
cpos = 0;
|
|
while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) {
|
|
if (strncmp(de->name, MSDOS_DOT , MSDOS_NAME) &&
|
|
strncmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) {
|
|
result = -ENOTEMPTY;
|
|
break;
|
|
}
|
|
}
|
|
brelse(bh);
|
|
return result;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fat_dir_empty);
|
|
|
|
/*
|
|
* fat_subdirs counts the number of sub-directories of dir. It can be run
|
|
* on directories being created.
|
|
*/
|
|
int fat_subdirs(struct inode *dir)
|
|
{
|
|
struct buffer_head *bh;
|
|
struct msdos_dir_entry *de;
|
|
loff_t cpos;
|
|
int count = 0;
|
|
|
|
bh = NULL;
|
|
cpos = 0;
|
|
while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) {
|
|
if (de->attr & ATTR_DIR)
|
|
count++;
|
|
}
|
|
brelse(bh);
|
|
return count;
|
|
}
|
|
|
|
/*
|
|
* Scans a directory for a given file (name points to its formatted name).
|
|
* Returns an error code or zero.
|
|
*/
|
|
int fat_scan(struct inode *dir, const unsigned char *name,
|
|
struct fat_slot_info *sinfo)
|
|
{
|
|
struct super_block *sb = dir->i_sb;
|
|
|
|
sinfo->slot_off = 0;
|
|
sinfo->bh = NULL;
|
|
while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh,
|
|
&sinfo->de) >= 0) {
|
|
if (!strncmp(sinfo->de->name, name, MSDOS_NAME)) {
|
|
sinfo->slot_off -= sizeof(*sinfo->de);
|
|
sinfo->nr_slots = 1;
|
|
sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
|
|
return 0;
|
|
}
|
|
}
|
|
return -ENOENT;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fat_scan);
|
|
|
|
/*
|
|
* Scans a directory for a given logstart.
|
|
* Returns an error code or zero.
|
|
*/
|
|
int fat_scan_logstart(struct inode *dir, int i_logstart,
|
|
struct fat_slot_info *sinfo)
|
|
{
|
|
struct super_block *sb = dir->i_sb;
|
|
|
|
sinfo->slot_off = 0;
|
|
sinfo->bh = NULL;
|
|
while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh,
|
|
&sinfo->de) >= 0) {
|
|
if (fat_get_start(MSDOS_SB(sb), sinfo->de) == i_logstart) {
|
|
sinfo->slot_off -= sizeof(*sinfo->de);
|
|
sinfo->nr_slots = 1;
|
|
sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
|
|
return 0;
|
|
}
|
|
}
|
|
return -ENOENT;
|
|
}
|
|
|
|
static int __fat_remove_entries(struct inode *dir, loff_t pos, int nr_slots)
|
|
{
|
|
struct super_block *sb = dir->i_sb;
|
|
struct buffer_head *bh;
|
|
struct msdos_dir_entry *de, *endp;
|
|
int err = 0, orig_slots;
|
|
|
|
while (nr_slots) {
|
|
bh = NULL;
|
|
if (fat_get_entry(dir, &pos, &bh, &de) < 0) {
|
|
err = -EIO;
|
|
break;
|
|
}
|
|
|
|
orig_slots = nr_slots;
|
|
endp = (struct msdos_dir_entry *)(bh->b_data + sb->s_blocksize);
|
|
while (nr_slots && de < endp) {
|
|
de->name[0] = DELETED_FLAG;
|
|
de++;
|
|
nr_slots--;
|
|
}
|
|
mark_buffer_dirty_inode(bh, dir);
|
|
if (IS_DIRSYNC(dir))
|
|
err = sync_dirty_buffer(bh);
|
|
brelse(bh);
|
|
if (err)
|
|
break;
|
|
|
|
/* pos is *next* de's position, so this does `- sizeof(de)' */
|
|
pos += ((orig_slots - nr_slots) * sizeof(*de)) - sizeof(*de);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo)
|
|
{
|
|
struct super_block *sb = dir->i_sb;
|
|
struct msdos_dir_entry *de;
|
|
struct buffer_head *bh;
|
|
int err = 0, nr_slots;
|
|
|
|
/*
|
|
* First stage: Remove the shortname. By this, the directory
|
|
* entry is removed.
|
|
*/
|
|
nr_slots = sinfo->nr_slots;
|
|
de = sinfo->de;
|
|
sinfo->de = NULL;
|
|
bh = sinfo->bh;
|
|
sinfo->bh = NULL;
|
|
while (nr_slots && de >= (struct msdos_dir_entry *)bh->b_data) {
|
|
de->name[0] = DELETED_FLAG;
|
|
de--;
|
|
nr_slots--;
|
|
}
|
|
mark_buffer_dirty_inode(bh, dir);
|
|
if (IS_DIRSYNC(dir))
|
|
err = sync_dirty_buffer(bh);
|
|
brelse(bh);
|
|
if (err)
|
|
return err;
|
|
dir->i_version++;
|
|
|
|
if (nr_slots) {
|
|
/*
|
|
* Second stage: remove the remaining longname slots.
|
|
* (This directory entry is already removed, and so return
|
|
* the success)
|
|
*/
|
|
err = __fat_remove_entries(dir, sinfo->slot_off, nr_slots);
|
|
if (err) {
|
|
fat_msg(sb, KERN_WARNING,
|
|
"Couldn't remove the long name slots");
|
|
}
|
|
}
|
|
|
|
dir->i_mtime = dir->i_atime = current_time(dir);
|
|
if (IS_DIRSYNC(dir))
|
|
(void)fat_sync_inode(dir);
|
|
else
|
|
mark_inode_dirty(dir);
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fat_remove_entries);
|
|
|
|
static int fat_zeroed_cluster(struct inode *dir, sector_t blknr, int nr_used,
|
|
struct buffer_head **bhs, int nr_bhs)
|
|
{
|
|
struct super_block *sb = dir->i_sb;
|
|
sector_t last_blknr = blknr + MSDOS_SB(sb)->sec_per_clus;
|
|
int err, i, n;
|
|
|
|
/* Zeroing the unused blocks on this cluster */
|
|
blknr += nr_used;
|
|
n = nr_used;
|
|
while (blknr < last_blknr) {
|
|
bhs[n] = sb_getblk(sb, blknr);
|
|
if (!bhs[n]) {
|
|
err = -ENOMEM;
|
|
goto error;
|
|
}
|
|
memset(bhs[n]->b_data, 0, sb->s_blocksize);
|
|
set_buffer_uptodate(bhs[n]);
|
|
mark_buffer_dirty_inode(bhs[n], dir);
|
|
|
|
n++;
|
|
blknr++;
|
|
if (n == nr_bhs) {
|
|
if (IS_DIRSYNC(dir)) {
|
|
err = fat_sync_bhs(bhs, n);
|
|
if (err)
|
|
goto error;
|
|
}
|
|
for (i = 0; i < n; i++)
|
|
brelse(bhs[i]);
|
|
n = 0;
|
|
}
|
|
}
|
|
if (IS_DIRSYNC(dir)) {
|
|
err = fat_sync_bhs(bhs, n);
|
|
if (err)
|
|
goto error;
|
|
}
|
|
for (i = 0; i < n; i++)
|
|
brelse(bhs[i]);
|
|
|
|
return 0;
|
|
|
|
error:
|
|
for (i = 0; i < n; i++)
|
|
bforget(bhs[i]);
|
|
return err;
|
|
}
|
|
|
|
int fat_alloc_new_dir(struct inode *dir, struct timespec *ts)
|
|
{
|
|
struct super_block *sb = dir->i_sb;
|
|
struct msdos_sb_info *sbi = MSDOS_SB(sb);
|
|
struct buffer_head *bhs[MAX_BUF_PER_PAGE];
|
|
struct msdos_dir_entry *de;
|
|
sector_t blknr;
|
|
__le16 date, time;
|
|
u8 time_cs;
|
|
int err, cluster;
|
|
|
|
err = fat_alloc_clusters(dir, &cluster, 1);
|
|
if (err)
|
|
goto error;
|
|
|
|
blknr = fat_clus_to_blknr(sbi, cluster);
|
|
bhs[0] = sb_getblk(sb, blknr);
|
|
if (!bhs[0]) {
|
|
err = -ENOMEM;
|
|
goto error_free;
|
|
}
|
|
|
|
fat_time_unix2fat(sbi, ts, &time, &date, &time_cs);
|
|
|
|
de = (struct msdos_dir_entry *)bhs[0]->b_data;
|
|
/* filling the new directory slots ("." and ".." entries) */
|
|
memcpy(de[0].name, MSDOS_DOT, MSDOS_NAME);
|
|
memcpy(de[1].name, MSDOS_DOTDOT, MSDOS_NAME);
|
|
de->attr = de[1].attr = ATTR_DIR;
|
|
de[0].lcase = de[1].lcase = 0;
|
|
de[0].time = de[1].time = time;
|
|
de[0].date = de[1].date = date;
|
|
if (sbi->options.isvfat) {
|
|
/* extra timestamps */
|
|
de[0].ctime = de[1].ctime = time;
|
|
de[0].ctime_cs = de[1].ctime_cs = time_cs;
|
|
de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = date;
|
|
} else {
|
|
de[0].ctime = de[1].ctime = 0;
|
|
de[0].ctime_cs = de[1].ctime_cs = 0;
|
|
de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = 0;
|
|
}
|
|
fat_set_start(&de[0], cluster);
|
|
fat_set_start(&de[1], MSDOS_I(dir)->i_logstart);
|
|
de[0].size = de[1].size = 0;
|
|
memset(de + 2, 0, sb->s_blocksize - 2 * sizeof(*de));
|
|
set_buffer_uptodate(bhs[0]);
|
|
mark_buffer_dirty_inode(bhs[0], dir);
|
|
|
|
err = fat_zeroed_cluster(dir, blknr, 1, bhs, MAX_BUF_PER_PAGE);
|
|
if (err)
|
|
goto error_free;
|
|
|
|
return cluster;
|
|
|
|
error_free:
|
|
fat_free_clusters(dir, cluster);
|
|
error:
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fat_alloc_new_dir);
|
|
|
|
static int fat_add_new_entries(struct inode *dir, void *slots, int nr_slots,
|
|
int *nr_cluster, struct msdos_dir_entry **de,
|
|
struct buffer_head **bh, loff_t *i_pos)
|
|
{
|
|
struct super_block *sb = dir->i_sb;
|
|
struct msdos_sb_info *sbi = MSDOS_SB(sb);
|
|
struct buffer_head *bhs[MAX_BUF_PER_PAGE];
|
|
sector_t blknr, start_blknr, last_blknr;
|
|
unsigned long size, copy;
|
|
int err, i, n, offset, cluster[2];
|
|
|
|
/*
|
|
* The minimum cluster size is 512bytes, and maximum entry
|
|
* size is 32*slots (672bytes). So, iff the cluster size is
|
|
* 512bytes, we may need two clusters.
|
|
*/
|
|
size = nr_slots * sizeof(struct msdos_dir_entry);
|
|
*nr_cluster = (size + (sbi->cluster_size - 1)) >> sbi->cluster_bits;
|
|
BUG_ON(*nr_cluster > 2);
|
|
|
|
err = fat_alloc_clusters(dir, cluster, *nr_cluster);
|
|
if (err)
|
|
goto error;
|
|
|
|
/*
|
|
* First stage: Fill the directory entry. NOTE: This cluster
|
|
* is not referenced from any inode yet, so updates order is
|
|
* not important.
|
|
*/
|
|
i = n = copy = 0;
|
|
do {
|
|
start_blknr = blknr = fat_clus_to_blknr(sbi, cluster[i]);
|
|
last_blknr = start_blknr + sbi->sec_per_clus;
|
|
while (blknr < last_blknr) {
|
|
bhs[n] = sb_getblk(sb, blknr);
|
|
if (!bhs[n]) {
|
|
err = -ENOMEM;
|
|
goto error_nomem;
|
|
}
|
|
|
|
/* fill the directory entry */
|
|
copy = min(size, sb->s_blocksize);
|
|
memcpy(bhs[n]->b_data, slots, copy);
|
|
slots += copy;
|
|
size -= copy;
|
|
set_buffer_uptodate(bhs[n]);
|
|
mark_buffer_dirty_inode(bhs[n], dir);
|
|
if (!size)
|
|
break;
|
|
n++;
|
|
blknr++;
|
|
}
|
|
} while (++i < *nr_cluster);
|
|
|
|
memset(bhs[n]->b_data + copy, 0, sb->s_blocksize - copy);
|
|
offset = copy - sizeof(struct msdos_dir_entry);
|
|
get_bh(bhs[n]);
|
|
*bh = bhs[n];
|
|
*de = (struct msdos_dir_entry *)((*bh)->b_data + offset);
|
|
*i_pos = fat_make_i_pos(sb, *bh, *de);
|
|
|
|
/* Second stage: clear the rest of cluster, and write outs */
|
|
err = fat_zeroed_cluster(dir, start_blknr, ++n, bhs, MAX_BUF_PER_PAGE);
|
|
if (err)
|
|
goto error_free;
|
|
|
|
return cluster[0];
|
|
|
|
error_free:
|
|
brelse(*bh);
|
|
*bh = NULL;
|
|
n = 0;
|
|
error_nomem:
|
|
for (i = 0; i < n; i++)
|
|
bforget(bhs[i]);
|
|
fat_free_clusters(dir, cluster[0]);
|
|
error:
|
|
return err;
|
|
}
|
|
|
|
int fat_add_entries(struct inode *dir, void *slots, int nr_slots,
|
|
struct fat_slot_info *sinfo)
|
|
{
|
|
struct super_block *sb = dir->i_sb;
|
|
struct msdos_sb_info *sbi = MSDOS_SB(sb);
|
|
struct buffer_head *bh, *prev, *bhs[3]; /* 32*slots (672bytes) */
|
|
struct msdos_dir_entry *uninitialized_var(de);
|
|
int err, free_slots, i, nr_bhs;
|
|
loff_t pos, i_pos;
|
|
|
|
sinfo->nr_slots = nr_slots;
|
|
|
|
/* First stage: search free directory entries */
|
|
free_slots = nr_bhs = 0;
|
|
bh = prev = NULL;
|
|
pos = 0;
|
|
err = -ENOSPC;
|
|
while (fat_get_entry(dir, &pos, &bh, &de) > -1) {
|
|
/* check the maximum size of directory */
|
|
if (pos >= FAT_MAX_DIR_SIZE)
|
|
goto error;
|
|
|
|
if (IS_FREE(de->name)) {
|
|
if (prev != bh) {
|
|
get_bh(bh);
|
|
bhs[nr_bhs] = prev = bh;
|
|
nr_bhs++;
|
|
}
|
|
free_slots++;
|
|
if (free_slots == nr_slots)
|
|
goto found;
|
|
} else {
|
|
for (i = 0; i < nr_bhs; i++)
|
|
brelse(bhs[i]);
|
|
prev = NULL;
|
|
free_slots = nr_bhs = 0;
|
|
}
|
|
}
|
|
if (dir->i_ino == MSDOS_ROOT_INO) {
|
|
if (sbi->fat_bits != 32)
|
|
goto error;
|
|
} else if (MSDOS_I(dir)->i_start == 0) {
|
|
fat_msg(sb, KERN_ERR, "Corrupted directory (i_pos %lld)",
|
|
MSDOS_I(dir)->i_pos);
|
|
err = -EIO;
|
|
goto error;
|
|
}
|
|
|
|
found:
|
|
err = 0;
|
|
pos -= free_slots * sizeof(*de);
|
|
nr_slots -= free_slots;
|
|
if (free_slots) {
|
|
/*
|
|
* Second stage: filling the free entries with new entries.
|
|
* NOTE: If this slots has shortname, first, we write
|
|
* the long name slots, then write the short name.
|
|
*/
|
|
int size = free_slots * sizeof(*de);
|
|
int offset = pos & (sb->s_blocksize - 1);
|
|
int long_bhs = nr_bhs - (nr_slots == 0);
|
|
|
|
/* Fill the long name slots. */
|
|
for (i = 0; i < long_bhs; i++) {
|
|
int copy = min_t(int, sb->s_blocksize - offset, size);
|
|
memcpy(bhs[i]->b_data + offset, slots, copy);
|
|
mark_buffer_dirty_inode(bhs[i], dir);
|
|
offset = 0;
|
|
slots += copy;
|
|
size -= copy;
|
|
}
|
|
if (long_bhs && IS_DIRSYNC(dir))
|
|
err = fat_sync_bhs(bhs, long_bhs);
|
|
if (!err && i < nr_bhs) {
|
|
/* Fill the short name slot. */
|
|
int copy = min_t(int, sb->s_blocksize - offset, size);
|
|
memcpy(bhs[i]->b_data + offset, slots, copy);
|
|
mark_buffer_dirty_inode(bhs[i], dir);
|
|
if (IS_DIRSYNC(dir))
|
|
err = sync_dirty_buffer(bhs[i]);
|
|
}
|
|
for (i = 0; i < nr_bhs; i++)
|
|
brelse(bhs[i]);
|
|
if (err)
|
|
goto error_remove;
|
|
}
|
|
|
|
if (nr_slots) {
|
|
int cluster, nr_cluster;
|
|
|
|
/*
|
|
* Third stage: allocate the cluster for new entries.
|
|
* And initialize the cluster with new entries, then
|
|
* add the cluster to dir.
|
|
*/
|
|
cluster = fat_add_new_entries(dir, slots, nr_slots, &nr_cluster,
|
|
&de, &bh, &i_pos);
|
|
if (cluster < 0) {
|
|
err = cluster;
|
|
goto error_remove;
|
|
}
|
|
err = fat_chain_add(dir, cluster, nr_cluster);
|
|
if (err) {
|
|
fat_free_clusters(dir, cluster);
|
|
goto error_remove;
|
|
}
|
|
if (dir->i_size & (sbi->cluster_size - 1)) {
|
|
fat_fs_error(sb, "Odd directory size");
|
|
dir->i_size = (dir->i_size + sbi->cluster_size - 1)
|
|
& ~((loff_t)sbi->cluster_size - 1);
|
|
}
|
|
dir->i_size += nr_cluster << sbi->cluster_bits;
|
|
MSDOS_I(dir)->mmu_private += nr_cluster << sbi->cluster_bits;
|
|
}
|
|
sinfo->slot_off = pos;
|
|
sinfo->de = de;
|
|
sinfo->bh = bh;
|
|
sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
|
|
|
|
return 0;
|
|
|
|
error:
|
|
brelse(bh);
|
|
for (i = 0; i < nr_bhs; i++)
|
|
brelse(bhs[i]);
|
|
return err;
|
|
|
|
error_remove:
|
|
brelse(bh);
|
|
if (free_slots)
|
|
__fat_remove_entries(dir, pos, free_slots);
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fat_add_entries);
|