| /* |
| * linux/fs/vfat/namei.c |
| * |
| * Written 1992,1993 by Werner Almesberger |
| * |
| * Windows95/Windows NT compatible extended MSDOS filesystem |
| * by Gordon Chaffee Copyright (C) 1995. Send bug reports for the |
| * VFAT filesystem to <chaffee@cs.berkeley.edu>. Specify |
| * what file operation caused you trouble and if you can duplicate |
| * the problem, send a script that demonstrates it. |
| * |
| * Short name translation 1999, 2001 by Wolfram Pienkoss <wp@bszh.de> |
| * |
| * Support Multibyte characters and cleanup by |
| * OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/jiffies.h> |
| #include <linux/ctype.h> |
| #include <linux/slab.h> |
| #include <linux/buffer_head.h> |
| #include <linux/namei.h> |
| #include "fat.h" |
| |
| /* |
| * If new entry was created in the parent, it could create the 8.3 |
| * alias (the shortname of logname). So, the parent may have the |
| * negative-dentry which matches the created 8.3 alias. |
| * |
| * If it happened, the negative dentry isn't actually negative |
| * anymore. So, drop it. |
| */ |
| static int vfat_revalidate_shortname(struct dentry *dentry) |
| { |
| int ret = 1; |
| spin_lock(&dentry->d_lock); |
| if (dentry->d_time != dentry->d_parent->d_inode->i_version) |
| ret = 0; |
| spin_unlock(&dentry->d_lock); |
| return ret; |
| } |
| |
| static int vfat_revalidate(struct dentry *dentry, unsigned int flags) |
| { |
| if (flags & LOOKUP_RCU) |
| return -ECHILD; |
| |
| /* This is not negative dentry. Always valid. */ |
| if (dentry->d_inode) |
| return 1; |
| return vfat_revalidate_shortname(dentry); |
| } |
| |
| static int vfat_revalidate_ci(struct dentry *dentry, unsigned int flags) |
| { |
| if (flags & LOOKUP_RCU) |
| return -ECHILD; |
| |
| /* |
| * This is not negative dentry. Always valid. |
| * |
| * Note, rename() to existing directory entry will have ->d_inode, |
| * and will use existing name which isn't specified name by user. |
| * |
| * We may be able to drop this positive dentry here. But dropping |
| * positive dentry isn't good idea. So it's unsupported like |
| * rename("filename", "FILENAME") for now. |
| */ |
| if (dentry->d_inode) |
| return 1; |
| |
| /* |
| * This may be nfsd (or something), anyway, we can't see the |
| * intent of this. So, since this can be for creation, drop it. |
| */ |
| if (!flags) |
| return 0; |
| |
| /* |
| * Drop the negative dentry, in order to make sure to use the |
| * case sensitive name which is specified by user if this is |
| * for creation. |
| */ |
| if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET)) |
| return 0; |
| |
| return vfat_revalidate_shortname(dentry); |
| } |
| |
| /* returns the length of a struct qstr, ignoring trailing dots */ |
| static unsigned int __vfat_striptail_len(unsigned int len, const char *name) |
| { |
| while (len && name[len - 1] == '.') |
| len--; |
| return len; |
| } |
| |
| static unsigned int vfat_striptail_len(const struct qstr *qstr) |
| { |
| return __vfat_striptail_len(qstr->len, qstr->name); |
| } |
| |
| /* |
| * Compute the hash for the vfat name corresponding to the dentry. |
| * Note: if the name is invalid, we leave the hash code unchanged so |
| * that the existing dentry can be used. The vfat fs routines will |
| * return ENOENT or EINVAL as appropriate. |
| */ |
| static int vfat_hash(const struct dentry *dentry, const struct inode *inode, |
| struct qstr *qstr) |
| { |
| qstr->hash = full_name_hash(qstr->name, vfat_striptail_len(qstr)); |
| return 0; |
| } |
| |
| /* |
| * Compute the hash for the vfat name corresponding to the dentry. |
| * Note: if the name is invalid, we leave the hash code unchanged so |
| * that the existing dentry can be used. The vfat fs routines will |
| * return ENOENT or EINVAL as appropriate. |
| */ |
| static int vfat_hashi(const struct dentry *dentry, const struct inode *inode, |
| struct qstr *qstr) |
| { |
| struct nls_table *t = MSDOS_SB(dentry->d_sb)->nls_io; |
| const unsigned char *name; |
| unsigned int len; |
| unsigned long hash; |
| |
| name = qstr->name; |
| len = vfat_striptail_len(qstr); |
| |
| hash = init_name_hash(); |
| while (len--) |
| hash = partial_name_hash(nls_tolower(t, *name++), hash); |
| qstr->hash = end_name_hash(hash); |
| |
| return 0; |
| } |
| |
| /* |
| * Case insensitive compare of two vfat names. |
| */ |
| static int vfat_cmpi(const struct dentry *parent, const struct inode *pinode, |
| const struct dentry *dentry, const struct inode *inode, |
| unsigned int len, const char *str, const struct qstr *name) |
| { |
| struct nls_table *t = MSDOS_SB(parent->d_sb)->nls_io; |
| unsigned int alen, blen; |
| |
| /* A filename cannot end in '.' or we treat it like it has none */ |
| alen = vfat_striptail_len(name); |
| blen = __vfat_striptail_len(len, str); |
| if (alen == blen) { |
| if (nls_strnicmp(t, name->name, str, alen) == 0) |
| return 0; |
| } |
| return 1; |
| } |
| |
| /* |
| * Case sensitive compare of two vfat names. |
| */ |
| static int vfat_cmp(const struct dentry *parent, const struct inode *pinode, |
| const struct dentry *dentry, const struct inode *inode, |
| unsigned int len, const char *str, const struct qstr *name) |
| { |
| unsigned int alen, blen; |
| |
| /* A filename cannot end in '.' or we treat it like it has none */ |
| alen = vfat_striptail_len(name); |
| blen = __vfat_striptail_len(len, str); |
| if (alen == blen) { |
| if (strncmp(name->name, str, alen) == 0) |
| return 0; |
| } |
| return 1; |
| } |
| |
| static const struct dentry_operations vfat_ci_dentry_ops = { |
| .d_revalidate = vfat_revalidate_ci, |
| .d_hash = vfat_hashi, |
| .d_compare = vfat_cmpi, |
| }; |
| |
| static const struct dentry_operations vfat_dentry_ops = { |
| .d_revalidate = vfat_revalidate, |
| .d_hash = vfat_hash, |
| .d_compare = vfat_cmp, |
| }; |
| |
| /* Characters that are undesirable in an MS-DOS file name */ |
| |
| static inline wchar_t vfat_bad_char(wchar_t w) |
| { |
| return (w < 0x0020) |
| || (w == '*') || (w == '?') || (w == '<') || (w == '>') |
| || (w == '|') || (w == '"') || (w == ':') || (w == '/') |
| || (w == '\\'); |
| } |
| |
| static inline wchar_t vfat_replace_char(wchar_t w) |
| { |
| return (w == '[') || (w == ']') || (w == ';') || (w == ',') |
| || (w == '+') || (w == '='); |
| } |
| |
| static wchar_t vfat_skip_char(wchar_t w) |
| { |
| return (w == '.') || (w == ' '); |
| } |
| |
| static inline int vfat_is_used_badchars(const wchar_t *s, int len) |
| { |
| int i; |
| |
| for (i = 0; i < len; i++) |
| if (vfat_bad_char(s[i])) |
| return -EINVAL; |
| |
| if (s[i - 1] == ' ') /* last character cannot be space */ |
| return -EINVAL; |
| |
| return 0; |
| } |
| |
| static int vfat_find_form(struct inode *dir, unsigned char *name) |
| { |
| struct fat_slot_info sinfo; |
| int err = fat_scan(dir, name, &sinfo); |
| if (err) |
| return -ENOENT; |
| brelse(sinfo.bh); |
| return 0; |
| } |
| |
| /* |
| * 1) Valid characters for the 8.3 format alias are any combination of |
| * letters, uppercase alphabets, digits, any of the |
| * following special characters: |
| * $ % ' ` - @ { } ~ ! # ( ) & _ ^ |
| * In this case Longfilename is not stored in disk. |
| * |
| * WinNT's Extension: |
| * File name and extension name is contain uppercase/lowercase |
| * only. And it is expressed by CASE_LOWER_BASE and CASE_LOWER_EXT. |
| * |
| * 2) File name is 8.3 format, but it contain the uppercase and |
| * lowercase char, muliti bytes char, etc. In this case numtail is not |
| * added, but Longfilename is stored. |
| * |
| * 3) When the one except for the above, or the following special |
| * character are contained: |
| * . [ ] ; , + = |
| * numtail is added, and Longfilename must be stored in disk . |
| */ |
| struct shortname_info { |
| unsigned char lower:1, |
| upper:1, |
| valid:1; |
| }; |
| #define INIT_SHORTNAME_INFO(x) do { \ |
| (x)->lower = 1; \ |
| (x)->upper = 1; \ |
| (x)->valid = 1; \ |
| } while (0) |
| |
| static inline int to_shortname_char(struct nls_table *nls, |
| unsigned char *buf, int buf_size, |
| wchar_t *src, struct shortname_info *info) |
| { |
| int len; |
| |
| if (vfat_skip_char(*src)) { |
| info->valid = 0; |
| return 0; |
| } |
| if (vfat_replace_char(*src)) { |
| info->valid = 0; |
| buf[0] = '_'; |
| return 1; |
| } |
| |
| len = nls->uni2char(*src, buf, buf_size); |
| if (len <= 0) { |
| info->valid = 0; |
| buf[0] = '_'; |
| len = 1; |
| } else if (len == 1) { |
| unsigned char prev = buf[0]; |
| |
| if (buf[0] >= 0x7F) { |
| info->lower = 0; |
| info->upper = 0; |
| } |
| |
| buf[0] = nls_toupper(nls, buf[0]); |
| if (isalpha(buf[0])) { |
| if (buf[0] == prev) |
| info->lower = 0; |
| else |
| info->upper = 0; |
| } |
| } else { |
| info->lower = 0; |
| info->upper = 0; |
| } |
| |
| return len; |
| } |
| |
| /* |
| * Given a valid longname, create a unique shortname. Make sure the |
| * shortname does not exist |
| * Returns negative number on error, 0 for a normal |
| * return, and 1 for valid shortname |
| */ |
| static int vfat_create_shortname(struct inode *dir, struct nls_table *nls, |
| wchar_t *uname, int ulen, |
| unsigned char *name_res, unsigned char *lcase) |
| { |
| struct fat_mount_options *opts = &MSDOS_SB(dir->i_sb)->options; |
| wchar_t *ip, *ext_start, *end, *name_start; |
| unsigned char base[9], ext[4], buf[5], *p; |
| unsigned char charbuf[NLS_MAX_CHARSET_SIZE]; |
| int chl, chi; |
| int sz = 0, extlen, baselen, i, numtail_baselen, numtail2_baselen; |
| int is_shortname; |
| struct shortname_info base_info, ext_info; |
| |
| is_shortname = 1; |
| INIT_SHORTNAME_INFO(&base_info); |
| INIT_SHORTNAME_INFO(&ext_info); |
| |
| /* Now, we need to create a shortname from the long name */ |
| ext_start = end = &uname[ulen]; |
| while (--ext_start >= uname) { |
| if (*ext_start == 0x002E) { /* is `.' */ |
| if (ext_start == end - 1) { |
| sz = ulen; |
| ext_start = NULL; |
| } |
| break; |
| } |
| } |
| |
| if (ext_start == uname - 1) { |
| sz = ulen; |
| ext_start = NULL; |
| } else if (ext_start) { |
| /* |
| * Names which start with a dot could be just |
| * an extension eg. "...test". In this case Win95 |
| * uses the extension as the name and sets no extension. |
| */ |
| name_start = &uname[0]; |
| while (name_start < ext_start) { |
| if (!vfat_skip_char(*name_start)) |
| break; |
| name_start++; |
| } |
| if (name_start != ext_start) { |
| sz = ext_start - uname; |
| ext_start++; |
| } else { |
| sz = ulen; |
| ext_start = NULL; |
| } |
| } |
| |
| numtail_baselen = 6; |
| numtail2_baselen = 2; |
| for (baselen = i = 0, p = base, ip = uname; i < sz; i++, ip++) { |
| chl = to_shortname_char(nls, charbuf, sizeof(charbuf), |
| ip, &base_info); |
| if (chl == 0) |
| continue; |
| |
| if (baselen < 2 && (baselen + chl) > 2) |
| numtail2_baselen = baselen; |
| if (baselen < 6 && (baselen + chl) > 6) |
| numtail_baselen = baselen; |
| for (chi = 0; chi < chl; chi++) { |
| *p++ = charbuf[chi]; |
| baselen++; |
| if (baselen >= 8) |
| break; |
| } |
| if (baselen >= 8) { |
| if ((chi < chl - 1) || (ip + 1) - uname < sz) |
| is_shortname = 0; |
| break; |
| } |
| } |
| if (baselen == 0) { |
| return -EINVAL; |
| } |
| |
| extlen = 0; |
| if (ext_start) { |
| for (p = ext, ip = ext_start; extlen < 3 && ip < end; ip++) { |
| chl = to_shortname_char(nls, charbuf, sizeof(charbuf), |
| ip, &ext_info); |
| if (chl == 0) |
| continue; |
| |
| if ((extlen + chl) > 3) { |
| is_shortname = 0; |
| break; |
| } |
| for (chi = 0; chi < chl; chi++) { |
| *p++ = charbuf[chi]; |
| extlen++; |
| } |
| if (extlen >= 3) { |
| if (ip + 1 != end) |
| is_shortname = 0; |
| break; |
| } |
| } |
| } |
| ext[extlen] = '\0'; |
| base[baselen] = '\0'; |
| |
| /* Yes, it can happen. ".\xe5" would do it. */ |
| if (base[0] == DELETED_FLAG) |
| base[0] = 0x05; |
| |
| /* OK, at this point we know that base is not longer than 8 symbols, |
| * ext is not longer than 3, base is nonempty, both don't contain |
| * any bad symbols (lowercase transformed to uppercase). |
| */ |
| |
| memset(name_res, ' ', MSDOS_NAME); |
| memcpy(name_res, base, baselen); |
| memcpy(name_res + 8, ext, extlen); |
| *lcase = 0; |
| if (is_shortname && base_info.valid && ext_info.valid) { |
| if (vfat_find_form(dir, name_res) == 0) |
| return -EEXIST; |
| |
| if (opts->shortname & VFAT_SFN_CREATE_WIN95) { |
| return (base_info.upper && ext_info.upper); |
| } else if (opts->shortname & VFAT_SFN_CREATE_WINNT) { |
| if ((base_info.upper || base_info.lower) && |
| (ext_info.upper || ext_info.lower)) { |
| if (!base_info.upper && base_info.lower) |
| *lcase |= CASE_LOWER_BASE; |
| if (!ext_info.upper && ext_info.lower) |
| *lcase |= CASE_LOWER_EXT; |
| return 1; |
| } |
| return 0; |
| } else { |
| BUG(); |
| } |
| } |
| |
| if (opts->numtail == 0) |
| if (vfat_find_form(dir, name_res) < 0) |
| return 0; |
| |
| /* |
| * Try to find a unique extension. This used to |
| * iterate through all possibilities sequentially, |
| * but that gave extremely bad performance. Windows |
| * only tries a few cases before using random |
| * values for part of the base. |
| */ |
| |
| if (baselen > 6) { |
| baselen = numtail_baselen; |
| name_res[7] = ' '; |
| } |
| name_res[baselen] = '~'; |
| for (i = 1; i < 10; i++) { |
| name_res[baselen + 1] = i + '0'; |
| if (vfat_find_form(dir, name_res) < 0) |
| return 0; |
| } |
| |
| i = jiffies; |
| sz = (jiffies >> 16) & 0x7; |
| if (baselen > 2) { |
| baselen = numtail2_baselen; |
| name_res[7] = ' '; |
| } |
| name_res[baselen + 4] = '~'; |
| name_res[baselen + 5] = '1' + sz; |
| while (1) { |
| snprintf(buf, sizeof(buf), "%04X", i & 0xffff); |
| memcpy(&name_res[baselen], buf, 4); |
| if (vfat_find_form(dir, name_res) < 0) |
| break; |
| i -= 11; |
| } |
| return 0; |
| } |
| |
| /* Translate a string, including coded sequences into Unicode */ |
| static int |
| xlate_to_uni(const unsigned char *name, int len, unsigned char *outname, |
| int *longlen, int *outlen, int escape, int utf8, |
| struct nls_table *nls) |
| { |
| const unsigned char *ip; |
| unsigned char nc; |
| unsigned char *op; |
| unsigned int ec; |
| int i, k, fill; |
| int charlen; |
| |
| if (utf8) { |
| *outlen = utf8s_to_utf16s(name, len, UTF16_HOST_ENDIAN, |
| (wchar_t *) outname, FAT_LFN_LEN + 2); |
| if (*outlen < 0) |
| return *outlen; |
| else if (*outlen > FAT_LFN_LEN) |
| return -ENAMETOOLONG; |
| |
| op = &outname[*outlen * sizeof(wchar_t)]; |
| } else { |
| for (i = 0, ip = name, op = outname, *outlen = 0; |
| i < len && *outlen < FAT_LFN_LEN; |
| *outlen += 1) { |
| if (escape && (*ip == ':')) { |
| if (i > len - 5) |
| return -EINVAL; |
| ec = 0; |
| for (k = 1; k < 5; k++) { |
| nc = ip[k]; |
| ec <<= 4; |
| if (nc >= '0' && nc <= '9') { |
| ec |= nc - '0'; |
| continue; |
| } |
| if (nc >= 'a' && nc <= 'f') { |
| ec |= nc - ('a' - 10); |
| continue; |
| } |
| if (nc >= 'A' && nc <= 'F') { |
| ec |= nc - ('A' - 10); |
| continue; |
| } |
| return -EINVAL; |
| } |
| *op++ = ec & 0xFF; |
| *op++ = ec >> 8; |
| ip += 5; |
| i += 5; |
| } else { |
| charlen = nls->char2uni(ip, len - i, |
| (wchar_t *)op); |
| if (charlen < 0) |
| return -EINVAL; |
| ip += charlen; |
| i += charlen; |
| op += 2; |
| } |
| } |
| if (i < len) |
| return -ENAMETOOLONG; |
| } |
| |
| *longlen = *outlen; |
| if (*outlen % 13) { |
| *op++ = 0; |
| *op++ = 0; |
| *outlen += 1; |
| if (*outlen % 13) { |
| fill = 13 - (*outlen % 13); |
| for (i = 0; i < fill; i++) { |
| *op++ = 0xff; |
| *op++ = 0xff; |
| } |
| *outlen += fill; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int vfat_build_slots(struct inode *dir, const unsigned char *name, |
| int len, int is_dir, int cluster, |
| struct timespec *ts, |
| struct msdos_dir_slot *slots, int *nr_slots) |
| { |
| struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb); |
| struct fat_mount_options *opts = &sbi->options; |
| struct msdos_dir_slot *ps; |
| struct msdos_dir_entry *de; |
| unsigned char cksum, lcase; |
| unsigned char msdos_name[MSDOS_NAME]; |
| wchar_t *uname; |
| __le16 time, date; |
| u8 time_cs; |
| int err, ulen, usize, i; |
| loff_t offset; |
| |
| *nr_slots = 0; |
| |
| uname = __getname(); |
| if (!uname) |
| return -ENOMEM; |
| |
| err = xlate_to_uni(name, len, (unsigned char *)uname, &ulen, &usize, |
| opts->unicode_xlate, opts->utf8, sbi->nls_io); |
| if (err) |
| goto out_free; |
| |
| err = vfat_is_used_badchars(uname, ulen); |
| if (err) |
| goto out_free; |
| |
| err = vfat_create_shortname(dir, sbi->nls_disk, uname, ulen, |
| msdos_name, &lcase); |
| if (err < 0) |
| goto out_free; |
| else if (err == 1) { |
| de = (struct msdos_dir_entry *)slots; |
| err = 0; |
| goto shortname; |
| } |
| |
| /* build the entry of long file name */ |
| cksum = fat_checksum(msdos_name); |
| |
| *nr_slots = usize / 13; |
| for (ps = slots, i = *nr_slots; i > 0; i--, ps++) { |
| ps->id = i; |
| ps->attr = ATTR_EXT; |
| ps->reserved = 0; |
| ps->alias_checksum = cksum; |
| ps->start = 0; |
| offset = (i - 1) * 13; |
| fatwchar_to16(ps->name0_4, uname + offset, 5); |
| fatwchar_to16(ps->name5_10, uname + offset + 5, 6); |
| fatwchar_to16(ps->name11_12, uname + offset + 11, 2); |
| } |
| slots[0].id |= 0x40; |
| de = (struct msdos_dir_entry *)ps; |
| |
| shortname: |
| /* build the entry of 8.3 alias name */ |
| (*nr_slots)++; |
| memcpy(de->name, msdos_name, MSDOS_NAME); |
| de->attr = is_dir ? ATTR_DIR : ATTR_ARCH; |
| de->lcase = lcase; |
| fat_time_unix2fat(sbi, ts, &time, &date, &time_cs); |
| de->time = de->ctime = time; |
| de->date = de->cdate = de->adate = date; |
| de->ctime_cs = time_cs; |
| de->start = cpu_to_le16(cluster); |
| de->starthi = cpu_to_le16(cluster >> 16); |
| de->size = 0; |
| out_free: |
| __putname(uname); |
| return err; |
| } |
| |
| static int vfat_add_entry(struct inode *dir, struct qstr *qname, int is_dir, |
| int cluster, struct timespec *ts, |
| struct fat_slot_info *sinfo) |
| { |
| struct msdos_dir_slot *slots; |
| unsigned int len; |
| int err, nr_slots; |
| |
| len = vfat_striptail_len(qname); |
| if (len == 0) |
| return -ENOENT; |
| |
| slots = kmalloc(sizeof(*slots) * MSDOS_SLOTS, GFP_NOFS); |
| if (slots == NULL) |
| return -ENOMEM; |
| |
| err = vfat_build_slots(dir, qname->name, len, is_dir, cluster, ts, |
| slots, &nr_slots); |
| if (err) |
| goto cleanup; |
| |
| err = fat_add_entries(dir, slots, nr_slots, sinfo); |
| if (err) |
| goto cleanup; |
| |
| /* update timestamp */ |
| dir->i_ctime = dir->i_mtime = dir->i_atime = *ts; |
| if (IS_DIRSYNC(dir)) |
| (void)fat_sync_inode(dir); |
| else |
| mark_inode_dirty(dir); |
| cleanup: |
| kfree(slots); |
| return err; |
| } |
| |
| static int vfat_find(struct inode *dir, struct qstr *qname, |
| struct fat_slot_info *sinfo) |
| { |
| unsigned int len = vfat_striptail_len(qname); |
| if (len == 0) |
| return -ENOENT; |
| return fat_search_long(dir, qname->name, len, sinfo); |
| } |
| |
| /* |
| * (nfsd's) anonymous disconnected dentry? |
| * NOTE: !IS_ROOT() is not anonymous (I.e. d_splice_alias() did the job). |
| */ |
| static int vfat_d_anon_disconn(struct dentry *dentry) |
| { |
| return IS_ROOT(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED); |
| } |
| |
| static struct dentry *vfat_lookup(struct inode *dir, struct dentry *dentry, |
| struct nameidata *nd) |
| { |
| struct super_block *sb = dir->i_sb; |
| struct fat_slot_info sinfo; |
| struct inode *inode; |
| struct dentry *alias; |
| int err; |
| |
| lock_super(sb); |
| |
| err = vfat_find(dir, &dentry->d_name, &sinfo); |
| if (err) { |
| if (err == -ENOENT) { |
| inode = NULL; |
| goto out; |
| } |
| goto error; |
| } |
| |
| inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos); |
| brelse(sinfo.bh); |
| if (IS_ERR(inode)) { |
| err = PTR_ERR(inode); |
| goto error; |
| } |
| |
| alias = d_find_alias(inode); |
| if (alias && !vfat_d_anon_disconn(alias)) { |
| /* |
| * This inode has non anonymous-DCACHE_DISCONNECTED |
| * dentry. This means, the user did ->lookup() by an |
| * another name (longname vs 8.3 alias of it) in past. |
| * |
| * Switch to new one for reason of locality if possible. |
| */ |
| BUG_ON(d_unhashed(alias)); |
| if (!S_ISDIR(inode->i_mode)) |
| d_move(alias, dentry); |
| iput(inode); |
| unlock_super(sb); |
| return alias; |
| } else |
| dput(alias); |
| |
| out: |
| unlock_super(sb); |
| dentry->d_time = dentry->d_parent->d_inode->i_version; |
| dentry = d_splice_alias(inode, dentry); |
| if (dentry) |
| dentry->d_time = dentry->d_parent->d_inode->i_version; |
| return dentry; |
| |
| error: |
| unlock_super(sb); |
| return ERR_PTR(err); |
| } |
| |
| static int vfat_create(struct inode *dir, struct dentry *dentry, umode_t mode, |
| struct nameidata *nd) |
| { |
| struct super_block *sb = dir->i_sb; |
| struct inode *inode; |
| struct fat_slot_info sinfo; |
| struct timespec ts; |
| int err; |
| |
| lock_super(sb); |
| |
| ts = CURRENT_TIME_SEC; |
| err = vfat_add_entry(dir, &dentry->d_name, 0, 0, &ts, &sinfo); |
| if (err) |
| goto out; |
| dir->i_version++; |
| |
| inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos); |
| brelse(sinfo.bh); |
| if (IS_ERR(inode)) { |
| err = PTR_ERR(inode); |
| goto out; |
| } |
| inode->i_version++; |
| inode->i_mtime = inode->i_atime = inode->i_ctime = ts; |
| /* timestamp is already written, so mark_inode_dirty() is unneeded. */ |
| |
| dentry->d_time = dentry->d_parent->d_inode->i_version; |
| d_instantiate(dentry, inode); |
| out: |
| unlock_super(sb); |
| return err; |
| } |
| |
| static int vfat_rmdir(struct inode *dir, struct dentry *dentry) |
| { |
| struct inode *inode = dentry->d_inode; |
| struct super_block *sb = dir->i_sb; |
| struct fat_slot_info sinfo; |
| int err; |
| |
| lock_super(sb); |
| |
| err = fat_dir_empty(inode); |
| if (err) |
| goto out; |
| err = vfat_find(dir, &dentry->d_name, &sinfo); |
| if (err) |
| goto out; |
| |
| err = fat_remove_entries(dir, &sinfo); /* and releases bh */ |
| if (err) |
| goto out; |
| drop_nlink(dir); |
| |
| clear_nlink(inode); |
| inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC; |
| fat_detach(inode); |
| out: |
| unlock_super(sb); |
| |
| return err; |
| } |
| |
| static int vfat_unlink(struct inode *dir, struct dentry *dentry) |
| { |
| struct inode *inode = dentry->d_inode; |
| struct super_block *sb = dir->i_sb; |
| struct fat_slot_info sinfo; |
| int err; |
| |
| lock_super(sb); |
| |
| err = vfat_find(dir, &dentry->d_name, &sinfo); |
| if (err) |
| goto out; |
| |
| err = fat_remove_entries(dir, &sinfo); /* and releases bh */ |
| if (err) |
| goto out; |
| clear_nlink(inode); |
| inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC; |
| fat_detach(inode); |
| out: |
| unlock_super(sb); |
| |
| return err; |
| } |
| |
| static int vfat_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) |
| { |
| struct super_block *sb = dir->i_sb; |
| struct inode *inode; |
| struct fat_slot_info sinfo; |
| struct timespec ts; |
| int err, cluster; |
| |
| lock_super(sb); |
| |
| ts = CURRENT_TIME_SEC; |
| cluster = fat_alloc_new_dir(dir, &ts); |
| if (cluster < 0) { |
| err = cluster; |
| goto out; |
| } |
| err = vfat_add_entry(dir, &dentry->d_name, 1, cluster, &ts, &sinfo); |
| if (err) |
| goto out_free; |
| dir->i_version++; |
| inc_nlink(dir); |
| |
| inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos); |
| brelse(sinfo.bh); |
| if (IS_ERR(inode)) { |
| err = PTR_ERR(inode); |
| /* the directory was completed, just return a error */ |
| goto out; |
| } |
| inode->i_version++; |
| set_nlink(inode, 2); |
| inode->i_mtime = inode->i_atime = inode->i_ctime = ts; |
| /* timestamp is already written, so mark_inode_dirty() is unneeded. */ |
| |
| dentry->d_time = dentry->d_parent->d_inode->i_version; |
| d_instantiate(dentry, inode); |
| |
| unlock_super(sb); |
| return 0; |
| |
| out_free: |
| fat_free_clusters(dir, cluster); |
| out: |
| unlock_super(sb); |
| return err; |
| } |
| |
| static int vfat_rename(struct inode *old_dir, struct dentry *old_dentry, |
| struct inode *new_dir, struct dentry *new_dentry) |
| { |
| struct buffer_head *dotdot_bh; |
| struct msdos_dir_entry *dotdot_de; |
| struct inode *old_inode, *new_inode; |
| struct fat_slot_info old_sinfo, sinfo; |
| struct timespec ts; |
| loff_t dotdot_i_pos, new_i_pos; |
| int err, is_dir, update_dotdot, corrupt = 0; |
| struct super_block *sb = old_dir->i_sb; |
| |
| old_sinfo.bh = sinfo.bh = dotdot_bh = NULL; |
| old_inode = old_dentry->d_inode; |
| new_inode = new_dentry->d_inode; |
| lock_super(sb); |
| err = vfat_find(old_dir, &old_dentry->d_name, &old_sinfo); |
| if (err) |
| goto out; |
| |
| is_dir = S_ISDIR(old_inode->i_mode); |
| update_dotdot = (is_dir && old_dir != new_dir); |
| if (update_dotdot) { |
| if (fat_get_dotdot_entry(old_inode, &dotdot_bh, &dotdot_de, |
| &dotdot_i_pos) < 0) { |
| err = -EIO; |
| goto out; |
| } |
| } |
| |
| ts = CURRENT_TIME_SEC; |
| if (new_inode) { |
| if (is_dir) { |
| err = fat_dir_empty(new_inode); |
| if (err) |
| goto out; |
| } |
| new_i_pos = MSDOS_I(new_inode)->i_pos; |
| fat_detach(new_inode); |
| } else { |
| err = vfat_add_entry(new_dir, &new_dentry->d_name, is_dir, 0, |
| &ts, &sinfo); |
| if (err) |
| goto out; |
| new_i_pos = sinfo.i_pos; |
| } |
| new_dir->i_version++; |
| |
| fat_detach(old_inode); |
| fat_attach(old_inode, new_i_pos); |
| if (IS_DIRSYNC(new_dir)) { |
| err = fat_sync_inode(old_inode); |
| if (err) |
| goto error_inode; |
| } else |
| mark_inode_dirty(old_inode); |
| |
| if (update_dotdot) { |
| int start = MSDOS_I(new_dir)->i_logstart; |
| dotdot_de->start = cpu_to_le16(start); |
| dotdot_de->starthi = cpu_to_le16(start >> 16); |
| mark_buffer_dirty_inode(dotdot_bh, old_inode); |
| if (IS_DIRSYNC(new_dir)) { |
| err = sync_dirty_buffer(dotdot_bh); |
| if (err) |
| goto error_dotdot; |
| } |
| drop_nlink(old_dir); |
| if (!new_inode) |
| inc_nlink(new_dir); |
| } |
| |
| err = fat_remove_entries(old_dir, &old_sinfo); /* and releases bh */ |
| old_sinfo.bh = NULL; |
| if (err) |
| goto error_dotdot; |
| old_dir->i_version++; |
| old_dir->i_ctime = old_dir->i_mtime = ts; |
| if (IS_DIRSYNC(old_dir)) |
| (void)fat_sync_inode(old_dir); |
| else |
| mark_inode_dirty(old_dir); |
| |
| if (new_inode) { |
| drop_nlink(new_inode); |
| if (is_dir) |
| drop_nlink(new_inode); |
| new_inode->i_ctime = ts; |
| } |
| out: |
| brelse(sinfo.bh); |
| brelse(dotdot_bh); |
| brelse(old_sinfo.bh); |
| unlock_super(sb); |
| |
| return err; |
| |
| error_dotdot: |
| /* data cluster is shared, serious corruption */ |
| corrupt = 1; |
| |
| if (update_dotdot) { |
| int start = MSDOS_I(old_dir)->i_logstart; |
| dotdot_de->start = cpu_to_le16(start); |
| dotdot_de->starthi = cpu_to_le16(start >> 16); |
| mark_buffer_dirty_inode(dotdot_bh, old_inode); |
| corrupt |= sync_dirty_buffer(dotdot_bh); |
| } |
| error_inode: |
| fat_detach(old_inode); |
| fat_attach(old_inode, old_sinfo.i_pos); |
| if (new_inode) { |
| fat_attach(new_inode, new_i_pos); |
| if (corrupt) |
| corrupt |= fat_sync_inode(new_inode); |
| } else { |
| /* |
| * If new entry was not sharing the data cluster, it |
| * shouldn't be serious corruption. |
| */ |
| int err2 = fat_remove_entries(new_dir, &sinfo); |
| if (corrupt) |
| corrupt |= err2; |
| sinfo.bh = NULL; |
| } |
| if (corrupt < 0) { |
| fat_fs_error(new_dir->i_sb, |
| "%s: Filesystem corrupted (i_pos %lld)", |
| __func__, sinfo.i_pos); |
| } |
| goto out; |
| } |
| |
| static const struct inode_operations vfat_dir_inode_operations = { |
| .create = vfat_create, |
| .lookup = vfat_lookup, |
| .unlink = vfat_unlink, |
| .mkdir = vfat_mkdir, |
| .rmdir = vfat_rmdir, |
| .rename = vfat_rename, |
| .setattr = fat_setattr, |
| .getattr = fat_getattr, |
| }; |
| |
| static void setup(struct super_block *sb) |
| { |
| MSDOS_SB(sb)->dir_ops = &vfat_dir_inode_operations; |
| if (MSDOS_SB(sb)->options.name_check != 's') |
| sb->s_d_op = &vfat_ci_dentry_ops; |
| else |
| sb->s_d_op = &vfat_dentry_ops; |
| } |
| |
| static int vfat_fill_super(struct super_block *sb, void *data, int silent) |
| { |
| return fat_fill_super(sb, data, silent, 1, setup); |
| } |
| |
| static struct dentry *vfat_mount(struct file_system_type *fs_type, |
| int flags, const char *dev_name, |
| void *data) |
| { |
| return mount_bdev(fs_type, flags, dev_name, data, vfat_fill_super); |
| } |
| |
| static struct file_system_type vfat_fs_type = { |
| .owner = THIS_MODULE, |
| .name = "vfat", |
| .mount = vfat_mount, |
| .kill_sb = kill_block_super, |
| .fs_flags = FS_REQUIRES_DEV, |
| }; |
| MODULE_ALIAS_FS("vfat"); |
| |
| static int __init init_vfat_fs(void) |
| { |
| return register_filesystem(&vfat_fs_type); |
| } |
| |
| static void __exit exit_vfat_fs(void) |
| { |
| unregister_filesystem(&vfat_fs_type); |
| } |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_DESCRIPTION("VFAT filesystem support"); |
| MODULE_AUTHOR("Gordon Chaffee"); |
| |
| module_init(init_vfat_fs) |
| module_exit(exit_vfat_fs) |