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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/vfat
downloadlinux-linaro-stable-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'fs/vfat')
-rw-r--r--fs/vfat/Makefile7
-rw-r--r--fs/vfat/namei.c1082
2 files changed, 1089 insertions, 0 deletions
diff --git a/fs/vfat/Makefile b/fs/vfat/Makefile
new file mode 100644
index 000000000000..40f2798a4f08
--- /dev/null
+++ b/fs/vfat/Makefile
@@ -0,0 +1,7 @@
+#
+# Makefile for the linux vfat-filesystem routines.
+#
+
+obj-$(CONFIG_VFAT_FS) += vfat.o
+
+vfat-y := namei.o
diff --git a/fs/vfat/namei.c b/fs/vfat/namei.c
new file mode 100644
index 000000000000..1c6f6b57ef1c
--- /dev/null
+++ b/fs/vfat/namei.c
@@ -0,0 +1,1082 @@
+/*
+ * 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/msdos_fs.h>
+#include <linux/ctype.h>
+#include <linux/slab.h>
+#include <linux/smp_lock.h>
+#include <linux/buffer_head.h>
+#include <linux/namei.h>
+
+static int vfat_revalidate(struct dentry *dentry, struct nameidata *nd)
+{
+ int ret = 1;
+
+ if (!dentry->d_inode &&
+ nd && !(nd->flags & LOOKUP_CONTINUE) && (nd->flags & LOOKUP_CREATE))
+ /*
+ * negative dentry is dropped, in order to make sure
+ * to use the name which a user desires if this is
+ * create path.
+ */
+ ret = 0;
+ else {
+ 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;
+}
+
+/* returns the length of a struct qstr, ignoring trailing dots */
+static unsigned int vfat_striptail_len(struct qstr *qstr)
+{
+ unsigned int len = qstr->len;
+
+ while (len && qstr->name[len - 1] == '.')
+ len--;
+ return len;
+}
+
+/*
+ * 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(struct dentry *dentry, 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(struct dentry *dentry, struct qstr *qstr)
+{
+ struct nls_table *t = MSDOS_SB(dentry->d_inode->i_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(struct dentry *dentry, struct qstr *a, struct qstr *b)
+{
+ struct nls_table *t = MSDOS_SB(dentry->d_inode->i_sb)->nls_io;
+ unsigned int alen, blen;
+
+ /* A filename cannot end in '.' or we treat it like it has none */
+ alen = vfat_striptail_len(a);
+ blen = vfat_striptail_len(b);
+ if (alen == blen) {
+ if (nls_strnicmp(t, a->name, b->name, alen) == 0)
+ return 0;
+ }
+ return 1;
+}
+
+/*
+ * Case sensitive compare of two vfat names.
+ */
+static int vfat_cmp(struct dentry *dentry, struct qstr *a, struct qstr *b)
+{
+ unsigned int alen, blen;
+
+ /* A filename cannot end in '.' or we treat it like it has none */
+ alen = vfat_striptail_len(a);
+ blen = vfat_striptail_len(b);
+ if (alen == blen) {
+ if (strncmp(a->name, b->name, alen) == 0)
+ return 0;
+ }
+ return 1;
+}
+
+static struct dentry_operations vfat_dentry_ops[4] = {
+ {
+ .d_hash = vfat_hashi,
+ .d_compare = vfat_cmpi,
+ },
+ {
+ .d_revalidate = vfat_revalidate,
+ .d_hash = vfat_hashi,
+ .d_compare = vfat_cmpi,
+ },
+ {
+ .d_hash = vfat_hash,
+ .d_compare = vfat_cmp,
+ },
+ {
+ .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;
+ return 0;
+}
+
+static int vfat_valid_longname(const unsigned char *name, unsigned int len)
+{
+ if (name[len - 1] == ' ')
+ return -EINVAL;
+ if (len >= 256)
+ return -ENAMETOOLONG;
+
+ /* MS-DOS "device special files" */
+ if (len == 3 || (len > 3 && name[3] == '.')) { /* basename == 3 */
+ if (!strnicmp(name, "aux", 3) ||
+ !strnicmp(name, "con", 3) ||
+ !strnicmp(name, "nul", 3) ||
+ !strnicmp(name, "prn", 3))
+ return -EINVAL;
+ }
+ if (len == 4 || (len > 4 && name[4] == '.')) { /* basename == 4 */
+ /* "com1", "com2", ... */
+ if ('1' <= name[3] && name[3] <= '9') {
+ if (!strnicmp(name, "com", 3) ||
+ !strnicmp(name, "lpt", 3))
+ 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[8], *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 & 0xffff;
+ 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) {
+ sprintf(buf, "%04X", i);
+ 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) {
+ int name_len = strlen(name);
+
+ *outlen = utf8_mbstowcs((wchar_t *)outname, name, PAGE_SIZE);
+
+ /*
+ * We stripped '.'s before and set len appropriately,
+ * but utf8_mbstowcs doesn't care about len
+ */
+ *outlen -= (name_len - len);
+
+ op = &outname[*outlen * sizeof(wchar_t)];
+ } else {
+ if (nls) {
+ for (i = 0, ip = name, op = outname, *outlen = 0;
+ i < len && *outlen <= 260;
+ *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 {
+ if ((charlen = nls->char2uni(ip, len - i, (wchar_t *)op)) < 0)
+ return -EINVAL;
+ ip += charlen;
+ i += charlen;
+ op += 2;
+ }
+ }
+ } else {
+ for (i = 0, ip = name, op = outname, *outlen = 0;
+ i < len && *outlen <= 260;
+ i++, *outlen += 1)
+ {
+ *op++ = *ip++;
+ *op++ = 0;
+ }
+ }
+ }
+ if (*outlen > 260)
+ 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 long page;
+ unsigned char cksum, lcase;
+ unsigned char msdos_name[MSDOS_NAME];
+ wchar_t *uname;
+ __le16 time, date;
+ int err, ulen, usize, i;
+ loff_t offset;
+
+ *nr_slots = 0;
+ err = vfat_valid_longname(name, len);
+ if (err)
+ return err;
+
+ page = __get_free_page(GFP_KERNEL);
+ if (!page)
+ return -ENOMEM;
+
+ uname = (wchar_t *)page;
+ 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 */
+ for (cksum = i = 0; i < 11; i++)
+ cksum = (((cksum&1)<<7)|((cksum&0xfe)>>1)) + msdos_name[i];
+
+ *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_date_unix2dos(ts->tv_sec, &time, &date);
+ de->time = de->ctime = time;
+ de->date = de->cdate = de->adate = date;
+ de->ctime_cs = 0;
+ de->start = cpu_to_le16(cluster);
+ de->starthi = cpu_to_le16(cluster >> 16);
+ de->size = 0;
+out_free:
+ free_page(page);
+ 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_KERNEL);
+ 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);
+}
+
+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 = NULL;
+ struct dentry *alias;
+ int err, table;
+
+ lock_kernel();
+ table = (MSDOS_SB(sb)->options.name_check == 's') ? 2 : 0;
+ dentry->d_op = &vfat_dentry_ops[table];
+
+ err = vfat_find(dir, &dentry->d_name, &sinfo);
+ if (err) {
+ table++;
+ goto error;
+ }
+ inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
+ brelse(sinfo.bh);
+ if (IS_ERR(inode)) {
+ unlock_kernel();
+ return ERR_PTR(PTR_ERR(inode));
+ }
+ alias = d_find_alias(inode);
+ if (alias) {
+ if (d_invalidate(alias) == 0)
+ dput(alias);
+ else {
+ iput(inode);
+ unlock_kernel();
+ return alias;
+ }
+
+ }
+error:
+ unlock_kernel();
+ dentry->d_op = &vfat_dentry_ops[table];
+ dentry->d_time = dentry->d_parent->d_inode->i_version;
+ dentry = d_splice_alias(inode, dentry);
+ if (dentry) {
+ dentry->d_op = &vfat_dentry_ops[table];
+ dentry->d_time = dentry->d_parent->d_inode->i_version;
+ }
+ return dentry;
+}
+
+static int vfat_create(struct inode *dir, struct dentry *dentry, int 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_kernel();
+
+ 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_kernel();
+ return err;
+}
+
+static int vfat_rmdir(struct inode *dir, struct dentry *dentry)
+{
+ struct inode *inode = dentry->d_inode;
+ struct fat_slot_info sinfo;
+ int err;
+
+ lock_kernel();
+
+ 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;
+ dir->i_nlink--;
+
+ inode->i_nlink = 0;
+ inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC;
+ fat_detach(inode);
+out:
+ unlock_kernel();
+
+ return err;
+}
+
+static int vfat_unlink(struct inode *dir, struct dentry *dentry)
+{
+ struct inode *inode = dentry->d_inode;
+ struct fat_slot_info sinfo;
+ int err;
+
+ lock_kernel();
+
+ 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;
+ inode->i_nlink = 0;
+ inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC;
+ fat_detach(inode);
+out:
+ unlock_kernel();
+
+ return err;
+}
+
+static int vfat_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+{
+ struct super_block *sb = dir->i_sb;
+ struct inode *inode;
+ struct fat_slot_info sinfo;
+ struct timespec ts;
+ int err, cluster;
+
+ lock_kernel();
+
+ 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++;
+ dir->i_nlink++;
+
+ 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++;
+ inode->i_nlink = 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_kernel();
+ return 0;
+
+out_free:
+ fat_free_clusters(dir, cluster);
+out:
+ unlock_kernel();
+ 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;
+ loff_t dotdot_i_pos;
+ struct inode *old_inode, *new_inode;
+ struct fat_slot_info old_sinfo, sinfo;
+ struct timespec ts;
+ int err, is_dir, update_dotdot, corrupt = 0;
+
+ old_sinfo.bh = sinfo.bh = dotdot_bh = NULL;
+ old_inode = old_dentry->d_inode;
+ new_inode = new_dentry->d_inode;
+ lock_kernel();
+ 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) {
+ err = vfat_find(new_dir, &new_dentry->d_name, &sinfo);
+ if (err)
+ goto out;
+ if (MSDOS_I(new_inode)->i_pos != sinfo.i_pos) {
+ /* WTF??? Cry and fail. */
+ printk(KERN_WARNING "vfat_rename: fs corrupted\n");
+ goto out;
+ }
+
+ if (is_dir) {
+ err = fat_dir_empty(new_inode);
+ if (err)
+ goto out;
+ }
+ 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_dir->i_version++;
+
+ fat_detach(old_inode);
+ fat_attach(old_inode, sinfo.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(dotdot_bh);
+ if (IS_DIRSYNC(new_dir)) {
+ err = sync_dirty_buffer(dotdot_bh);
+ if (err)
+ goto error_dotdot;
+ }
+ old_dir->i_nlink--;
+ if (!new_inode)
+ new_dir->i_nlink++;
+ }
+
+ 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) {
+ if (is_dir)
+ new_inode->i_nlink -= 2;
+ else
+ new_inode->i_nlink--;
+ new_inode->i_ctime = ts;
+ }
+out:
+ brelse(sinfo.bh);
+ brelse(dotdot_bh);
+ brelse(old_sinfo.bh);
+ unlock_kernel();
+
+ 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(dotdot_bh);
+ 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, sinfo.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_panic(new_dir->i_sb,
+ "%s: Filesystem corrupted (i_pos %lld)",
+ __FUNCTION__, sinfo.i_pos);
+ }
+ goto out;
+}
+
+static 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_notify_change,
+};
+
+static int vfat_fill_super(struct super_block *sb, void *data, int silent)
+{
+ int res;
+
+ res = fat_fill_super(sb, data, silent, &vfat_dir_inode_operations, 1);
+ if (res)
+ return res;
+
+ if (MSDOS_SB(sb)->options.name_check != 's')
+ sb->s_root->d_op = &vfat_dentry_ops[0];
+ else
+ sb->s_root->d_op = &vfat_dentry_ops[2];
+
+ return 0;
+}
+
+static struct super_block *vfat_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name,
+ void *data)
+{
+ return get_sb_bdev(fs_type, flags, dev_name, data, vfat_fill_super);
+}
+
+static struct file_system_type vfat_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "vfat",
+ .get_sb = vfat_get_sb,
+ .kill_sb = kill_block_super,
+ .fs_flags = FS_REQUIRES_DEV,
+};
+
+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)