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-rw-r--r--fs/nilfs2/namei.c573
1 files changed, 573 insertions, 0 deletions
diff --git a/fs/nilfs2/namei.c b/fs/nilfs2/namei.c
new file mode 100644
index 000000000..23899e0ae
--- /dev/null
+++ b/fs/nilfs2/namei.c
@@ -0,0 +1,573 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * NILFS pathname lookup operations.
+ *
+ * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
+ *
+ * Modified for NILFS by Amagai Yoshiji and Ryusuke Konishi.
+ */
+/*
+ * linux/fs/ext2/namei.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ * from
+ *
+ * linux/fs/minix/namei.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * Big-endian to little-endian byte-swapping/bitmaps by
+ * David S. Miller (davem@caip.rutgers.edu), 1995
+ */
+
+#include <linux/pagemap.h>
+#include "nilfs.h"
+#include "export.h"
+
+#define NILFS_FID_SIZE_NON_CONNECTABLE \
+ (offsetof(struct nilfs_fid, parent_gen) / 4)
+#define NILFS_FID_SIZE_CONNECTABLE (sizeof(struct nilfs_fid) / 4)
+
+static inline int nilfs_add_nondir(struct dentry *dentry, struct inode *inode)
+{
+ int err = nilfs_add_link(dentry, inode);
+
+ if (!err) {
+ d_instantiate_new(dentry, inode);
+ return 0;
+ }
+ inode_dec_link_count(inode);
+ unlock_new_inode(inode);
+ iput(inode);
+ return err;
+}
+
+/*
+ * Methods themselves.
+ */
+
+static struct dentry *
+nilfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
+{
+ struct inode *inode;
+ ino_t ino;
+
+ if (dentry->d_name.len > NILFS_NAME_LEN)
+ return ERR_PTR(-ENAMETOOLONG);
+
+ ino = nilfs_inode_by_name(dir, &dentry->d_name);
+ inode = ino ? nilfs_iget(dir->i_sb, NILFS_I(dir)->i_root, ino) : NULL;
+ return d_splice_alias(inode, dentry);
+}
+
+/*
+ * By the time this is called, we already have created
+ * the directory cache entry for the new file, but it
+ * is so far negative - it has no inode.
+ *
+ * If the create succeeds, we fill in the inode information
+ * with d_instantiate().
+ */
+static int nilfs_create(struct user_namespace *mnt_userns, struct inode *dir,
+ struct dentry *dentry, umode_t mode, bool excl)
+{
+ struct inode *inode;
+ struct nilfs_transaction_info ti;
+ int err;
+
+ err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
+ if (err)
+ return err;
+ inode = nilfs_new_inode(dir, mode);
+ err = PTR_ERR(inode);
+ if (!IS_ERR(inode)) {
+ inode->i_op = &nilfs_file_inode_operations;
+ inode->i_fop = &nilfs_file_operations;
+ inode->i_mapping->a_ops = &nilfs_aops;
+ nilfs_mark_inode_dirty(inode);
+ err = nilfs_add_nondir(dentry, inode);
+ }
+ if (!err)
+ err = nilfs_transaction_commit(dir->i_sb);
+ else
+ nilfs_transaction_abort(dir->i_sb);
+
+ return err;
+}
+
+static int
+nilfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+ struct dentry *dentry, umode_t mode, dev_t rdev)
+{
+ struct inode *inode;
+ struct nilfs_transaction_info ti;
+ int err;
+
+ err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
+ if (err)
+ return err;
+ inode = nilfs_new_inode(dir, mode);
+ err = PTR_ERR(inode);
+ if (!IS_ERR(inode)) {
+ init_special_inode(inode, inode->i_mode, rdev);
+ nilfs_mark_inode_dirty(inode);
+ err = nilfs_add_nondir(dentry, inode);
+ }
+ if (!err)
+ err = nilfs_transaction_commit(dir->i_sb);
+ else
+ nilfs_transaction_abort(dir->i_sb);
+
+ return err;
+}
+
+static int nilfs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+ struct dentry *dentry, const char *symname)
+{
+ struct nilfs_transaction_info ti;
+ struct super_block *sb = dir->i_sb;
+ unsigned int l = strlen(symname) + 1;
+ struct inode *inode;
+ int err;
+
+ if (l > sb->s_blocksize)
+ return -ENAMETOOLONG;
+
+ err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
+ if (err)
+ return err;
+
+ inode = nilfs_new_inode(dir, S_IFLNK | 0777);
+ err = PTR_ERR(inode);
+ if (IS_ERR(inode))
+ goto out;
+
+ /* slow symlink */
+ inode->i_op = &nilfs_symlink_inode_operations;
+ inode_nohighmem(inode);
+ inode->i_mapping->a_ops = &nilfs_aops;
+ err = page_symlink(inode, symname, l);
+ if (err)
+ goto out_fail;
+
+ /* mark_inode_dirty(inode); */
+ /* page_symlink() do this */
+
+ err = nilfs_add_nondir(dentry, inode);
+out:
+ if (!err)
+ err = nilfs_transaction_commit(dir->i_sb);
+ else
+ nilfs_transaction_abort(dir->i_sb);
+
+ return err;
+
+out_fail:
+ drop_nlink(inode);
+ nilfs_mark_inode_dirty(inode);
+ unlock_new_inode(inode);
+ iput(inode);
+ goto out;
+}
+
+static int nilfs_link(struct dentry *old_dentry, struct inode *dir,
+ struct dentry *dentry)
+{
+ struct inode *inode = d_inode(old_dentry);
+ struct nilfs_transaction_info ti;
+ int err;
+
+ err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
+ if (err)
+ return err;
+
+ inode->i_ctime = current_time(inode);
+ inode_inc_link_count(inode);
+ ihold(inode);
+
+ err = nilfs_add_link(dentry, inode);
+ if (!err) {
+ d_instantiate(dentry, inode);
+ err = nilfs_transaction_commit(dir->i_sb);
+ } else {
+ inode_dec_link_count(inode);
+ iput(inode);
+ nilfs_transaction_abort(dir->i_sb);
+ }
+
+ return err;
+}
+
+static int nilfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+ struct dentry *dentry, umode_t mode)
+{
+ struct inode *inode;
+ struct nilfs_transaction_info ti;
+ int err;
+
+ err = nilfs_transaction_begin(dir->i_sb, &ti, 1);
+ if (err)
+ return err;
+
+ inc_nlink(dir);
+
+ inode = nilfs_new_inode(dir, S_IFDIR | mode);
+ err = PTR_ERR(inode);
+ if (IS_ERR(inode))
+ goto out_dir;
+
+ inode->i_op = &nilfs_dir_inode_operations;
+ inode->i_fop = &nilfs_dir_operations;
+ inode->i_mapping->a_ops = &nilfs_aops;
+
+ inc_nlink(inode);
+
+ err = nilfs_make_empty(inode, dir);
+ if (err)
+ goto out_fail;
+
+ err = nilfs_add_link(dentry, inode);
+ if (err)
+ goto out_fail;
+
+ nilfs_mark_inode_dirty(inode);
+ d_instantiate_new(dentry, inode);
+out:
+ if (!err)
+ err = nilfs_transaction_commit(dir->i_sb);
+ else
+ nilfs_transaction_abort(dir->i_sb);
+
+ return err;
+
+out_fail:
+ drop_nlink(inode);
+ drop_nlink(inode);
+ nilfs_mark_inode_dirty(inode);
+ unlock_new_inode(inode);
+ iput(inode);
+out_dir:
+ drop_nlink(dir);
+ nilfs_mark_inode_dirty(dir);
+ goto out;
+}
+
+static int nilfs_do_unlink(struct inode *dir, struct dentry *dentry)
+{
+ struct inode *inode;
+ struct nilfs_dir_entry *de;
+ struct page *page;
+ int err;
+
+ err = -ENOENT;
+ de = nilfs_find_entry(dir, &dentry->d_name, &page);
+ if (!de)
+ goto out;
+
+ inode = d_inode(dentry);
+ err = -EIO;
+ if (le64_to_cpu(de->inode) != inode->i_ino)
+ goto out;
+
+ if (!inode->i_nlink) {
+ nilfs_warn(inode->i_sb,
+ "deleting nonexistent file (ino=%lu), %d",
+ inode->i_ino, inode->i_nlink);
+ set_nlink(inode, 1);
+ }
+ err = nilfs_delete_entry(de, page);
+ if (err)
+ goto out;
+
+ inode->i_ctime = dir->i_ctime;
+ drop_nlink(inode);
+ err = 0;
+out:
+ return err;
+}
+
+static int nilfs_unlink(struct inode *dir, struct dentry *dentry)
+{
+ struct nilfs_transaction_info ti;
+ int err;
+
+ err = nilfs_transaction_begin(dir->i_sb, &ti, 0);
+ if (err)
+ return err;
+
+ err = nilfs_do_unlink(dir, dentry);
+
+ if (!err) {
+ nilfs_mark_inode_dirty(dir);
+ nilfs_mark_inode_dirty(d_inode(dentry));
+ err = nilfs_transaction_commit(dir->i_sb);
+ } else
+ nilfs_transaction_abort(dir->i_sb);
+
+ return err;
+}
+
+static int nilfs_rmdir(struct inode *dir, struct dentry *dentry)
+{
+ struct inode *inode = d_inode(dentry);
+ struct nilfs_transaction_info ti;
+ int err;
+
+ err = nilfs_transaction_begin(dir->i_sb, &ti, 0);
+ if (err)
+ return err;
+
+ err = -ENOTEMPTY;
+ if (nilfs_empty_dir(inode)) {
+ err = nilfs_do_unlink(dir, dentry);
+ if (!err) {
+ inode->i_size = 0;
+ drop_nlink(inode);
+ nilfs_mark_inode_dirty(inode);
+ drop_nlink(dir);
+ nilfs_mark_inode_dirty(dir);
+ }
+ }
+ if (!err)
+ err = nilfs_transaction_commit(dir->i_sb);
+ else
+ nilfs_transaction_abort(dir->i_sb);
+
+ return err;
+}
+
+static int nilfs_rename(struct user_namespace *mnt_userns,
+ struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry,
+ unsigned int flags)
+{
+ struct inode *old_inode = d_inode(old_dentry);
+ struct inode *new_inode = d_inode(new_dentry);
+ struct page *dir_page = NULL;
+ struct nilfs_dir_entry *dir_de = NULL;
+ struct page *old_page;
+ struct nilfs_dir_entry *old_de;
+ struct nilfs_transaction_info ti;
+ int err;
+
+ if (flags & ~RENAME_NOREPLACE)
+ return -EINVAL;
+
+ err = nilfs_transaction_begin(old_dir->i_sb, &ti, 1);
+ if (unlikely(err))
+ return err;
+
+ err = -ENOENT;
+ old_de = nilfs_find_entry(old_dir, &old_dentry->d_name, &old_page);
+ if (!old_de)
+ goto out;
+
+ if (S_ISDIR(old_inode->i_mode)) {
+ err = -EIO;
+ dir_de = nilfs_dotdot(old_inode, &dir_page);
+ if (!dir_de)
+ goto out_old;
+ }
+
+ if (new_inode) {
+ struct page *new_page;
+ struct nilfs_dir_entry *new_de;
+
+ err = -ENOTEMPTY;
+ if (dir_de && !nilfs_empty_dir(new_inode))
+ goto out_dir;
+
+ err = -ENOENT;
+ new_de = nilfs_find_entry(new_dir, &new_dentry->d_name, &new_page);
+ if (!new_de)
+ goto out_dir;
+ nilfs_set_link(new_dir, new_de, new_page, old_inode);
+ nilfs_mark_inode_dirty(new_dir);
+ new_inode->i_ctime = current_time(new_inode);
+ if (dir_de)
+ drop_nlink(new_inode);
+ drop_nlink(new_inode);
+ nilfs_mark_inode_dirty(new_inode);
+ } else {
+ err = nilfs_add_link(new_dentry, old_inode);
+ if (err)
+ goto out_dir;
+ if (dir_de) {
+ inc_nlink(new_dir);
+ nilfs_mark_inode_dirty(new_dir);
+ }
+ }
+
+ /*
+ * Like most other Unix systems, set the ctime for inodes on a
+ * rename.
+ */
+ old_inode->i_ctime = current_time(old_inode);
+
+ nilfs_delete_entry(old_de, old_page);
+
+ if (dir_de) {
+ nilfs_set_link(old_inode, dir_de, dir_page, new_dir);
+ drop_nlink(old_dir);
+ }
+ nilfs_mark_inode_dirty(old_dir);
+ nilfs_mark_inode_dirty(old_inode);
+
+ err = nilfs_transaction_commit(old_dir->i_sb);
+ return err;
+
+out_dir:
+ if (dir_de) {
+ kunmap(dir_page);
+ put_page(dir_page);
+ }
+out_old:
+ kunmap(old_page);
+ put_page(old_page);
+out:
+ nilfs_transaction_abort(old_dir->i_sb);
+ return err;
+}
+
+/*
+ * Export operations
+ */
+static struct dentry *nilfs_get_parent(struct dentry *child)
+{
+ unsigned long ino;
+ struct inode *inode;
+ struct nilfs_root *root;
+
+ ino = nilfs_inode_by_name(d_inode(child), &dotdot_name);
+ if (!ino)
+ return ERR_PTR(-ENOENT);
+
+ root = NILFS_I(d_inode(child))->i_root;
+
+ inode = nilfs_iget(child->d_sb, root, ino);
+ if (IS_ERR(inode))
+ return ERR_CAST(inode);
+
+ return d_obtain_alias(inode);
+}
+
+static struct dentry *nilfs_get_dentry(struct super_block *sb, u64 cno,
+ u64 ino, u32 gen)
+{
+ struct nilfs_root *root;
+ struct inode *inode;
+
+ if (ino < NILFS_FIRST_INO(sb) && ino != NILFS_ROOT_INO)
+ return ERR_PTR(-ESTALE);
+
+ root = nilfs_lookup_root(sb->s_fs_info, cno);
+ if (!root)
+ return ERR_PTR(-ESTALE);
+
+ inode = nilfs_iget(sb, root, ino);
+ nilfs_put_root(root);
+
+ if (IS_ERR(inode))
+ return ERR_CAST(inode);
+ if (gen && inode->i_generation != gen) {
+ iput(inode);
+ return ERR_PTR(-ESTALE);
+ }
+ return d_obtain_alias(inode);
+}
+
+static struct dentry *nilfs_fh_to_dentry(struct super_block *sb, struct fid *fh,
+ int fh_len, int fh_type)
+{
+ struct nilfs_fid *fid = (struct nilfs_fid *)fh;
+
+ if (fh_len < NILFS_FID_SIZE_NON_CONNECTABLE ||
+ (fh_type != FILEID_NILFS_WITH_PARENT &&
+ fh_type != FILEID_NILFS_WITHOUT_PARENT))
+ return NULL;
+
+ return nilfs_get_dentry(sb, fid->cno, fid->ino, fid->gen);
+}
+
+static struct dentry *nilfs_fh_to_parent(struct super_block *sb, struct fid *fh,
+ int fh_len, int fh_type)
+{
+ struct nilfs_fid *fid = (struct nilfs_fid *)fh;
+
+ if (fh_len < NILFS_FID_SIZE_CONNECTABLE ||
+ fh_type != FILEID_NILFS_WITH_PARENT)
+ return NULL;
+
+ return nilfs_get_dentry(sb, fid->cno, fid->parent_ino, fid->parent_gen);
+}
+
+static int nilfs_encode_fh(struct inode *inode, __u32 *fh, int *lenp,
+ struct inode *parent)
+{
+ struct nilfs_fid *fid = (struct nilfs_fid *)fh;
+ struct nilfs_root *root = NILFS_I(inode)->i_root;
+ int type;
+
+ if (parent && *lenp < NILFS_FID_SIZE_CONNECTABLE) {
+ *lenp = NILFS_FID_SIZE_CONNECTABLE;
+ return FILEID_INVALID;
+ }
+ if (*lenp < NILFS_FID_SIZE_NON_CONNECTABLE) {
+ *lenp = NILFS_FID_SIZE_NON_CONNECTABLE;
+ return FILEID_INVALID;
+ }
+
+ fid->cno = root->cno;
+ fid->ino = inode->i_ino;
+ fid->gen = inode->i_generation;
+
+ if (parent) {
+ fid->parent_ino = parent->i_ino;
+ fid->parent_gen = parent->i_generation;
+ type = FILEID_NILFS_WITH_PARENT;
+ *lenp = NILFS_FID_SIZE_CONNECTABLE;
+ } else {
+ type = FILEID_NILFS_WITHOUT_PARENT;
+ *lenp = NILFS_FID_SIZE_NON_CONNECTABLE;
+ }
+
+ return type;
+}
+
+const struct inode_operations nilfs_dir_inode_operations = {
+ .create = nilfs_create,
+ .lookup = nilfs_lookup,
+ .link = nilfs_link,
+ .unlink = nilfs_unlink,
+ .symlink = nilfs_symlink,
+ .mkdir = nilfs_mkdir,
+ .rmdir = nilfs_rmdir,
+ .mknod = nilfs_mknod,
+ .rename = nilfs_rename,
+ .setattr = nilfs_setattr,
+ .permission = nilfs_permission,
+ .fiemap = nilfs_fiemap,
+ .fileattr_get = nilfs_fileattr_get,
+ .fileattr_set = nilfs_fileattr_set,
+};
+
+const struct inode_operations nilfs_special_inode_operations = {
+ .setattr = nilfs_setattr,
+ .permission = nilfs_permission,
+};
+
+const struct inode_operations nilfs_symlink_inode_operations = {
+ .get_link = page_get_link,
+ .permission = nilfs_permission,
+};
+
+const struct export_operations nilfs_export_ops = {
+ .encode_fh = nilfs_encode_fh,
+ .fh_to_dentry = nilfs_fh_to_dentry,
+ .fh_to_parent = nilfs_fh_to_parent,
+ .get_parent = nilfs_get_parent,
+};