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-rw-r--r--fs/affs/namei.c462
1 files changed, 462 insertions, 0 deletions
diff --git a/fs/affs/namei.c b/fs/affs/namei.c
new file mode 100644
index 000000000..181e05b46
--- /dev/null
+++ b/fs/affs/namei.c
@@ -0,0 +1,462 @@
+/*
+ * linux/fs/affs/namei.c
+ *
+ * (c) 1996 Hans-Joachim Widmaier - Rewritten
+ *
+ * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem.
+ *
+ * (C) 1991 Linus Torvalds - minix filesystem
+ */
+
+#include "affs.h"
+
+typedef int (*toupper_t)(int);
+
+static int affs_toupper(int ch);
+static int affs_hash_dentry(const struct dentry *, struct qstr *);
+static int affs_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+ unsigned int len, const char *str, const struct qstr *name);
+static int affs_intl_toupper(int ch);
+static int affs_intl_hash_dentry(const struct dentry *, struct qstr *);
+static int affs_intl_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+ unsigned int len, const char *str, const struct qstr *name);
+
+const struct dentry_operations affs_dentry_operations = {
+ .d_hash = affs_hash_dentry,
+ .d_compare = affs_compare_dentry,
+};
+
+const struct dentry_operations affs_intl_dentry_operations = {
+ .d_hash = affs_intl_hash_dentry,
+ .d_compare = affs_intl_compare_dentry,
+};
+
+
+/* Simple toupper() for DOS\1 */
+
+static int
+affs_toupper(int ch)
+{
+ return ch >= 'a' && ch <= 'z' ? ch -= ('a' - 'A') : ch;
+}
+
+/* International toupper() for DOS\3 ("international") */
+
+static int
+affs_intl_toupper(int ch)
+{
+ return (ch >= 'a' && ch <= 'z') || (ch >= 0xE0
+ && ch <= 0xFE && ch != 0xF7) ?
+ ch - ('a' - 'A') : ch;
+}
+
+static inline toupper_t
+affs_get_toupper(struct super_block *sb)
+{
+ return affs_test_opt(AFFS_SB(sb)->s_flags, SF_INTL) ?
+ affs_intl_toupper : affs_toupper;
+}
+
+/*
+ * Note: the dentry argument is the parent dentry.
+ */
+static inline int
+__affs_hash_dentry(struct qstr *qstr, toupper_t toupper, bool notruncate)
+{
+ const u8 *name = qstr->name;
+ unsigned long hash;
+ int retval;
+ u32 len;
+
+ retval = affs_check_name(qstr->name, qstr->len, notruncate);
+ if (retval)
+ return retval;
+
+ hash = init_name_hash();
+ len = min(qstr->len, AFFSNAMEMAX);
+ for (; len > 0; name++, len--)
+ hash = partial_name_hash(toupper(*name), hash);
+ qstr->hash = end_name_hash(hash);
+
+ return 0;
+}
+
+static int
+affs_hash_dentry(const struct dentry *dentry, struct qstr *qstr)
+{
+ return __affs_hash_dentry(qstr, affs_toupper,
+ affs_nofilenametruncate(dentry));
+
+}
+
+static int
+affs_intl_hash_dentry(const struct dentry *dentry, struct qstr *qstr)
+{
+ return __affs_hash_dentry(qstr, affs_intl_toupper,
+ affs_nofilenametruncate(dentry));
+
+}
+
+static inline int __affs_compare_dentry(unsigned int len,
+ const char *str, const struct qstr *name, toupper_t toupper,
+ bool notruncate)
+{
+ const u8 *aname = str;
+ const u8 *bname = name->name;
+
+ /*
+ * 'str' is the name of an already existing dentry, so the name
+ * must be valid. 'name' must be validated first.
+ */
+
+ if (affs_check_name(name->name, name->len, notruncate))
+ return 1;
+
+ /*
+ * If the names are longer than the allowed 30 chars,
+ * the excess is ignored, so their length may differ.
+ */
+ if (len >= AFFSNAMEMAX) {
+ if (name->len < AFFSNAMEMAX)
+ return 1;
+ len = AFFSNAMEMAX;
+ } else if (len != name->len)
+ return 1;
+
+ for (; len > 0; len--)
+ if (toupper(*aname++) != toupper(*bname++))
+ return 1;
+
+ return 0;
+}
+
+static int
+affs_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+ unsigned int len, const char *str, const struct qstr *name)
+{
+
+ return __affs_compare_dentry(len, str, name, affs_toupper,
+ affs_nofilenametruncate(parent));
+}
+
+static int
+affs_intl_compare_dentry(const struct dentry *parent, const struct dentry *dentry,
+ unsigned int len, const char *str, const struct qstr *name)
+{
+ return __affs_compare_dentry(len, str, name, affs_intl_toupper,
+ affs_nofilenametruncate(parent));
+
+}
+
+/*
+ * NOTE! unlike strncmp, affs_match returns 1 for success, 0 for failure.
+ */
+
+static inline int
+affs_match(struct dentry *dentry, const u8 *name2, toupper_t toupper)
+{
+ const u8 *name = dentry->d_name.name;
+ int len = dentry->d_name.len;
+
+ if (len >= AFFSNAMEMAX) {
+ if (*name2 < AFFSNAMEMAX)
+ return 0;
+ len = AFFSNAMEMAX;
+ } else if (len != *name2)
+ return 0;
+
+ for (name2++; len > 0; len--)
+ if (toupper(*name++) != toupper(*name2++))
+ return 0;
+ return 1;
+}
+
+int
+affs_hash_name(struct super_block *sb, const u8 *name, unsigned int len)
+{
+ toupper_t toupper = affs_get_toupper(sb);
+ u32 hash;
+
+ hash = len = min(len, AFFSNAMEMAX);
+ for (; len > 0; len--)
+ hash = (hash * 13 + toupper(*name++)) & 0x7ff;
+
+ return hash % AFFS_SB(sb)->s_hashsize;
+}
+
+static struct buffer_head *
+affs_find_entry(struct inode *dir, struct dentry *dentry)
+{
+ struct super_block *sb = dir->i_sb;
+ struct buffer_head *bh;
+ toupper_t toupper = affs_get_toupper(sb);
+ u32 key;
+
+ pr_debug("%s(\"%pd\")\n", __func__, dentry);
+
+ bh = affs_bread(sb, dir->i_ino);
+ if (!bh)
+ return ERR_PTR(-EIO);
+
+ key = be32_to_cpu(AFFS_HEAD(bh)->table[affs_hash_name(sb, dentry->d_name.name, dentry->d_name.len)]);
+
+ for (;;) {
+ affs_brelse(bh);
+ if (key == 0)
+ return NULL;
+ bh = affs_bread(sb, key);
+ if (!bh)
+ return ERR_PTR(-EIO);
+ if (affs_match(dentry, AFFS_TAIL(sb, bh)->name, toupper))
+ return bh;
+ key = be32_to_cpu(AFFS_TAIL(sb, bh)->hash_chain);
+ }
+}
+
+struct dentry *
+affs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
+{
+ struct super_block *sb = dir->i_sb;
+ struct buffer_head *bh;
+ struct inode *inode = NULL;
+
+ pr_debug("%s(\"%pd\")\n", __func__, dentry);
+
+ affs_lock_dir(dir);
+ bh = affs_find_entry(dir, dentry);
+ affs_unlock_dir(dir);
+ if (IS_ERR(bh))
+ return ERR_CAST(bh);
+ if (bh) {
+ u32 ino = bh->b_blocknr;
+
+ /* store the real header ino in d_fsdata for faster lookups */
+ dentry->d_fsdata = (void *)(long)ino;
+ switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) {
+ //link to dirs disabled
+ //case ST_LINKDIR:
+ case ST_LINKFILE:
+ ino = be32_to_cpu(AFFS_TAIL(sb, bh)->original);
+ }
+ affs_brelse(bh);
+ inode = affs_iget(sb, ino);
+ if (IS_ERR(inode))
+ return ERR_CAST(inode);
+ }
+ d_add(dentry, inode);
+ return NULL;
+}
+
+int
+affs_unlink(struct inode *dir, struct dentry *dentry)
+{
+ pr_debug("%s(dir=%lu, %lu \"%pd\")\n", __func__, dir->i_ino,
+ d_inode(dentry)->i_ino, dentry);
+
+ return affs_remove_header(dentry);
+}
+
+int
+affs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl)
+{
+ struct super_block *sb = dir->i_sb;
+ struct inode *inode;
+ int error;
+
+ pr_debug("%s(%lu,\"%pd\",0%ho)\n",
+ __func__, dir->i_ino, dentry, mode);
+
+ inode = affs_new_inode(dir);
+ if (!inode)
+ return -ENOSPC;
+
+ inode->i_mode = mode;
+ mode_to_prot(inode);
+ mark_inode_dirty(inode);
+
+ inode->i_op = &affs_file_inode_operations;
+ inode->i_fop = &affs_file_operations;
+ inode->i_mapping->a_ops = affs_test_opt(AFFS_SB(sb)->s_flags, SF_OFS) ?
+ &affs_aops_ofs : &affs_aops;
+ error = affs_add_entry(dir, inode, dentry, ST_FILE);
+ if (error) {
+ clear_nlink(inode);
+ iput(inode);
+ return error;
+ }
+ return 0;
+}
+
+int
+affs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+{
+ struct inode *inode;
+ int error;
+
+ pr_debug("%s(%lu,\"%pd\",0%ho)\n",
+ __func__, dir->i_ino, dentry, mode);
+
+ inode = affs_new_inode(dir);
+ if (!inode)
+ return -ENOSPC;
+
+ inode->i_mode = S_IFDIR | mode;
+ mode_to_prot(inode);
+
+ inode->i_op = &affs_dir_inode_operations;
+ inode->i_fop = &affs_dir_operations;
+
+ error = affs_add_entry(dir, inode, dentry, ST_USERDIR);
+ if (error) {
+ clear_nlink(inode);
+ mark_inode_dirty(inode);
+ iput(inode);
+ return error;
+ }
+ return 0;
+}
+
+int
+affs_rmdir(struct inode *dir, struct dentry *dentry)
+{
+ pr_debug("%s(dir=%lu, %lu \"%pd\")\n", __func__, dir->i_ino,
+ d_inode(dentry)->i_ino, dentry);
+
+ return affs_remove_header(dentry);
+}
+
+int
+affs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
+{
+ struct super_block *sb = dir->i_sb;
+ struct buffer_head *bh;
+ struct inode *inode;
+ char *p;
+ int i, maxlen, error;
+ char c, lc;
+
+ pr_debug("%s(%lu,\"%pd\" -> \"%s\")\n",
+ __func__, dir->i_ino, dentry, symname);
+
+ maxlen = AFFS_SB(sb)->s_hashsize * sizeof(u32) - 1;
+ inode = affs_new_inode(dir);
+ if (!inode)
+ return -ENOSPC;
+
+ inode->i_op = &affs_symlink_inode_operations;
+ inode->i_data.a_ops = &affs_symlink_aops;
+ inode->i_mode = S_IFLNK | 0777;
+ mode_to_prot(inode);
+
+ error = -EIO;
+ bh = affs_bread(sb, inode->i_ino);
+ if (!bh)
+ goto err;
+ i = 0;
+ p = (char *)AFFS_HEAD(bh)->table;
+ lc = '/';
+ if (*symname == '/') {
+ struct affs_sb_info *sbi = AFFS_SB(sb);
+ while (*symname == '/')
+ symname++;
+ spin_lock(&sbi->symlink_lock);
+ while (sbi->s_volume[i]) /* Cannot overflow */
+ *p++ = sbi->s_volume[i++];
+ spin_unlock(&sbi->symlink_lock);
+ }
+ while (i < maxlen && (c = *symname++)) {
+ if (c == '.' && lc == '/' && *symname == '.' && symname[1] == '/') {
+ *p++ = '/';
+ i++;
+ symname += 2;
+ lc = '/';
+ } else if (c == '.' && lc == '/' && *symname == '/') {
+ symname++;
+ lc = '/';
+ } else {
+ *p++ = c;
+ lc = c;
+ i++;
+ }
+ if (lc == '/')
+ while (*symname == '/')
+ symname++;
+ }
+ *p = 0;
+ mark_buffer_dirty_inode(bh, inode);
+ affs_brelse(bh);
+ mark_inode_dirty(inode);
+
+ error = affs_add_entry(dir, inode, dentry, ST_SOFTLINK);
+ if (error)
+ goto err;
+
+ return 0;
+
+err:
+ clear_nlink(inode);
+ mark_inode_dirty(inode);
+ iput(inode);
+ return error;
+}
+
+int
+affs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
+{
+ struct inode *inode = d_inode(old_dentry);
+
+ pr_debug("%s(%lu, %lu, \"%pd\")\n", __func__, inode->i_ino, dir->i_ino,
+ dentry);
+
+ return affs_add_entry(dir, inode, dentry, ST_LINKFILE);
+}
+
+int
+affs_rename(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry)
+{
+ struct super_block *sb = old_dir->i_sb;
+ struct buffer_head *bh = NULL;
+ int retval;
+
+ pr_debug("%s(old=%lu,\"%pd\" to new=%lu,\"%pd\")\n", __func__,
+ old_dir->i_ino, old_dentry, new_dir->i_ino, new_dentry);
+
+ retval = affs_check_name(new_dentry->d_name.name,
+ new_dentry->d_name.len,
+ affs_nofilenametruncate(old_dentry));
+
+ if (retval)
+ return retval;
+
+ /* Unlink destination if it already exists */
+ if (d_really_is_positive(new_dentry)) {
+ retval = affs_remove_header(new_dentry);
+ if (retval)
+ return retval;
+ }
+
+ bh = affs_bread(sb, d_inode(old_dentry)->i_ino);
+ if (!bh)
+ return -EIO;
+
+ /* Remove header from its parent directory. */
+ affs_lock_dir(old_dir);
+ retval = affs_remove_hash(old_dir, bh);
+ affs_unlock_dir(old_dir);
+ if (retval)
+ goto done;
+
+ /* And insert it into the new directory with the new name. */
+ affs_copy_name(AFFS_TAIL(sb, bh)->name, new_dentry);
+ affs_fix_checksum(sb, bh);
+ affs_lock_dir(new_dir);
+ retval = affs_insert_hash(new_dir, bh);
+ affs_unlock_dir(new_dir);
+ /* TODO: move it back to old_dir, if error? */
+
+done:
+ mark_buffer_dirty_inode(bh, retval ? old_dir : new_dir);
+ affs_brelse(bh);
+ return retval;
+}