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![Linus Torvalds](/assets/img/avatar_default.png)
Pull fourth vfs update from Al Viro: "d_inode() annotations from David Howells (sat in for-next since before the beginning of merge window) + four assorted fixes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: RCU pathwalk breakage when running into a symlink overmounting something fix I_DIO_WAKEUP definition direct-io: only inc/dec inode->i_dio_count for file systems fs/9p: fix readdir() VFS: assorted d_backing_inode() annotations VFS: fs/inode.c helpers: d_inode() annotations VFS: fs/cachefiles: d_backing_inode() annotations VFS: fs library helpers: d_inode() annotations VFS: assorted weird filesystems: d_inode() annotations VFS: normal filesystems (and lustre): d_inode() annotations VFS: security/: d_inode() annotations VFS: security/: d_backing_inode() annotations VFS: net/: d_inode() annotations VFS: net/unix: d_backing_inode() annotations VFS: kernel/: d_inode() annotations VFS: audit: d_backing_inode() annotations VFS: Fix up some ->d_inode accesses in the chelsio driver VFS: Cachefiles should perform fs modifications on the top layer only VFS: AF_UNIX sockets should call mknod on the top layer only
739 lines
21 KiB
C
739 lines
21 KiB
C
/*
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* inode.c - part of debugfs, a tiny little debug file system
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*
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* Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
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* Copyright (C) 2004 IBM Inc.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License version
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* 2 as published by the Free Software Foundation.
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*
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* debugfs is for people to use instead of /proc or /sys.
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* See Documentation/DocBook/kernel-api for more details.
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*
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*/
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#include <linux/module.h>
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#include <linux/fs.h>
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#include <linux/mount.h>
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#include <linux/pagemap.h>
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#include <linux/init.h>
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#include <linux/kobject.h>
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#include <linux/namei.h>
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#include <linux/debugfs.h>
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#include <linux/fsnotify.h>
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#include <linux/string.h>
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#include <linux/seq_file.h>
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#include <linux/parser.h>
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#include <linux/magic.h>
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#include <linux/slab.h>
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#define DEBUGFS_DEFAULT_MODE 0700
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static struct vfsmount *debugfs_mount;
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static int debugfs_mount_count;
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static bool debugfs_registered;
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static struct inode *debugfs_get_inode(struct super_block *sb)
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{
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struct inode *inode = new_inode(sb);
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if (inode) {
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inode->i_ino = get_next_ino();
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inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
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}
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return inode;
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}
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static inline int debugfs_positive(struct dentry *dentry)
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{
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return d_really_is_positive(dentry) && !d_unhashed(dentry);
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}
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struct debugfs_mount_opts {
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kuid_t uid;
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kgid_t gid;
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umode_t mode;
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};
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enum {
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Opt_uid,
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Opt_gid,
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Opt_mode,
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Opt_err
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};
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static const match_table_t tokens = {
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{Opt_uid, "uid=%u"},
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{Opt_gid, "gid=%u"},
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{Opt_mode, "mode=%o"},
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{Opt_err, NULL}
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};
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struct debugfs_fs_info {
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struct debugfs_mount_opts mount_opts;
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};
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static int debugfs_parse_options(char *data, struct debugfs_mount_opts *opts)
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{
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substring_t args[MAX_OPT_ARGS];
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int option;
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int token;
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kuid_t uid;
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kgid_t gid;
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char *p;
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opts->mode = DEBUGFS_DEFAULT_MODE;
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while ((p = strsep(&data, ",")) != NULL) {
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if (!*p)
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continue;
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token = match_token(p, tokens, args);
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switch (token) {
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case Opt_uid:
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if (match_int(&args[0], &option))
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return -EINVAL;
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uid = make_kuid(current_user_ns(), option);
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if (!uid_valid(uid))
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return -EINVAL;
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opts->uid = uid;
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break;
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case Opt_gid:
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if (match_int(&args[0], &option))
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return -EINVAL;
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gid = make_kgid(current_user_ns(), option);
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if (!gid_valid(gid))
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return -EINVAL;
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opts->gid = gid;
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break;
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case Opt_mode:
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if (match_octal(&args[0], &option))
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return -EINVAL;
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opts->mode = option & S_IALLUGO;
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break;
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/*
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* We might like to report bad mount options here;
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* but traditionally debugfs has ignored all mount options
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*/
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}
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}
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return 0;
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}
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static int debugfs_apply_options(struct super_block *sb)
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{
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struct debugfs_fs_info *fsi = sb->s_fs_info;
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struct inode *inode = d_inode(sb->s_root);
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struct debugfs_mount_opts *opts = &fsi->mount_opts;
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inode->i_mode &= ~S_IALLUGO;
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inode->i_mode |= opts->mode;
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inode->i_uid = opts->uid;
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inode->i_gid = opts->gid;
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return 0;
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}
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static int debugfs_remount(struct super_block *sb, int *flags, char *data)
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{
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int err;
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struct debugfs_fs_info *fsi = sb->s_fs_info;
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sync_filesystem(sb);
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err = debugfs_parse_options(data, &fsi->mount_opts);
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if (err)
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goto fail;
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debugfs_apply_options(sb);
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fail:
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return err;
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}
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static int debugfs_show_options(struct seq_file *m, struct dentry *root)
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{
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struct debugfs_fs_info *fsi = root->d_sb->s_fs_info;
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struct debugfs_mount_opts *opts = &fsi->mount_opts;
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if (!uid_eq(opts->uid, GLOBAL_ROOT_UID))
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seq_printf(m, ",uid=%u",
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from_kuid_munged(&init_user_ns, opts->uid));
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if (!gid_eq(opts->gid, GLOBAL_ROOT_GID))
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seq_printf(m, ",gid=%u",
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from_kgid_munged(&init_user_ns, opts->gid));
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if (opts->mode != DEBUGFS_DEFAULT_MODE)
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seq_printf(m, ",mode=%o", opts->mode);
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return 0;
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}
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static void debugfs_evict_inode(struct inode *inode)
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{
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truncate_inode_pages_final(&inode->i_data);
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clear_inode(inode);
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if (S_ISLNK(inode->i_mode))
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kfree(inode->i_private);
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}
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static const struct super_operations debugfs_super_operations = {
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.statfs = simple_statfs,
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.remount_fs = debugfs_remount,
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.show_options = debugfs_show_options,
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.evict_inode = debugfs_evict_inode,
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};
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static struct vfsmount *debugfs_automount(struct path *path)
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{
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struct vfsmount *(*f)(void *);
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f = (struct vfsmount *(*)(void *))path->dentry->d_fsdata;
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return f(d_inode(path->dentry)->i_private);
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}
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static const struct dentry_operations debugfs_dops = {
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.d_delete = always_delete_dentry,
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.d_automount = debugfs_automount,
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};
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static int debug_fill_super(struct super_block *sb, void *data, int silent)
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{
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static struct tree_descr debug_files[] = {{""}};
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struct debugfs_fs_info *fsi;
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int err;
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save_mount_options(sb, data);
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fsi = kzalloc(sizeof(struct debugfs_fs_info), GFP_KERNEL);
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sb->s_fs_info = fsi;
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if (!fsi) {
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err = -ENOMEM;
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goto fail;
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}
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err = debugfs_parse_options(data, &fsi->mount_opts);
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if (err)
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goto fail;
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err = simple_fill_super(sb, DEBUGFS_MAGIC, debug_files);
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if (err)
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goto fail;
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sb->s_op = &debugfs_super_operations;
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sb->s_d_op = &debugfs_dops;
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debugfs_apply_options(sb);
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return 0;
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fail:
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kfree(fsi);
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sb->s_fs_info = NULL;
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return err;
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}
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static struct dentry *debug_mount(struct file_system_type *fs_type,
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int flags, const char *dev_name,
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void *data)
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{
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return mount_single(fs_type, flags, data, debug_fill_super);
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}
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static struct file_system_type debug_fs_type = {
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.owner = THIS_MODULE,
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.name = "debugfs",
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.mount = debug_mount,
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.kill_sb = kill_litter_super,
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};
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MODULE_ALIAS_FS("debugfs");
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static struct dentry *start_creating(const char *name, struct dentry *parent)
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{
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struct dentry *dentry;
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int error;
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pr_debug("debugfs: creating file '%s'\n",name);
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if (IS_ERR(parent))
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return parent;
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error = simple_pin_fs(&debug_fs_type, &debugfs_mount,
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&debugfs_mount_count);
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if (error)
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return ERR_PTR(error);
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/* If the parent is not specified, we create it in the root.
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* We need the root dentry to do this, which is in the super
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* block. A pointer to that is in the struct vfsmount that we
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* have around.
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*/
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if (!parent)
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parent = debugfs_mount->mnt_root;
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mutex_lock(&d_inode(parent)->i_mutex);
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dentry = lookup_one_len(name, parent, strlen(name));
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if (!IS_ERR(dentry) && d_really_is_positive(dentry)) {
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dput(dentry);
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dentry = ERR_PTR(-EEXIST);
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}
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if (IS_ERR(dentry))
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mutex_unlock(&d_inode(parent)->i_mutex);
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return dentry;
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}
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static struct dentry *failed_creating(struct dentry *dentry)
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{
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mutex_unlock(&d_inode(dentry->d_parent)->i_mutex);
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dput(dentry);
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simple_release_fs(&debugfs_mount, &debugfs_mount_count);
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return NULL;
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}
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static struct dentry *end_creating(struct dentry *dentry)
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{
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mutex_unlock(&d_inode(dentry->d_parent)->i_mutex);
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return dentry;
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}
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/**
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* debugfs_create_file - create a file in the debugfs filesystem
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* @name: a pointer to a string containing the name of the file to create.
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* @mode: the permission that the file should have.
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* @parent: a pointer to the parent dentry for this file. This should be a
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* directory dentry if set. If this parameter is NULL, then the
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* file will be created in the root of the debugfs filesystem.
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* @data: a pointer to something that the caller will want to get to later
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* on. The inode.i_private pointer will point to this value on
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* the open() call.
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* @fops: a pointer to a struct file_operations that should be used for
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* this file.
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*
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* This is the basic "create a file" function for debugfs. It allows for a
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* wide range of flexibility in creating a file, or a directory (if you want
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* to create a directory, the debugfs_create_dir() function is
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* recommended to be used instead.)
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*
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* This function will return a pointer to a dentry if it succeeds. This
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* pointer must be passed to the debugfs_remove() function when the file is
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* to be removed (no automatic cleanup happens if your module is unloaded,
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* you are responsible here.) If an error occurs, %NULL will be returned.
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*
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* If debugfs is not enabled in the kernel, the value -%ENODEV will be
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* returned.
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*/
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struct dentry *debugfs_create_file(const char *name, umode_t mode,
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struct dentry *parent, void *data,
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const struct file_operations *fops)
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{
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struct dentry *dentry;
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struct inode *inode;
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if (!(mode & S_IFMT))
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mode |= S_IFREG;
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BUG_ON(!S_ISREG(mode));
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dentry = start_creating(name, parent);
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if (IS_ERR(dentry))
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return NULL;
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inode = debugfs_get_inode(dentry->d_sb);
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if (unlikely(!inode))
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return failed_creating(dentry);
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inode->i_mode = mode;
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inode->i_fop = fops ? fops : &debugfs_file_operations;
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inode->i_private = data;
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d_instantiate(dentry, inode);
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fsnotify_create(d_inode(dentry->d_parent), dentry);
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return end_creating(dentry);
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}
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EXPORT_SYMBOL_GPL(debugfs_create_file);
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|
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/**
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* debugfs_create_file_size - create a file in the debugfs filesystem
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* @name: a pointer to a string containing the name of the file to create.
|
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* @mode: the permission that the file should have.
|
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* @parent: a pointer to the parent dentry for this file. This should be a
|
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* directory dentry if set. If this parameter is NULL, then the
|
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* file will be created in the root of the debugfs filesystem.
|
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* @data: a pointer to something that the caller will want to get to later
|
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* on. The inode.i_private pointer will point to this value on
|
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* the open() call.
|
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* @fops: a pointer to a struct file_operations that should be used for
|
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* this file.
|
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* @file_size: initial file size
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|
*
|
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* This is the basic "create a file" function for debugfs. It allows for a
|
|
* wide range of flexibility in creating a file, or a directory (if you want
|
|
* to create a directory, the debugfs_create_dir() function is
|
|
* recommended to be used instead.)
|
|
*
|
|
* This function will return a pointer to a dentry if it succeeds. This
|
|
* pointer must be passed to the debugfs_remove() function when the file is
|
|
* to be removed (no automatic cleanup happens if your module is unloaded,
|
|
* you are responsible here.) If an error occurs, %NULL will be returned.
|
|
*
|
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* If debugfs is not enabled in the kernel, the value -%ENODEV will be
|
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* returned.
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*/
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struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
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struct dentry *parent, void *data,
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const struct file_operations *fops,
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loff_t file_size)
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{
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struct dentry *de = debugfs_create_file(name, mode, parent, data, fops);
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|
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if (de)
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d_inode(de)->i_size = file_size;
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return de;
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}
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EXPORT_SYMBOL_GPL(debugfs_create_file_size);
|
|
|
|
/**
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|
* debugfs_create_dir - create a directory in the debugfs filesystem
|
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* @name: a pointer to a string containing the name of the directory to
|
|
* create.
|
|
* @parent: a pointer to the parent dentry for this file. This should be a
|
|
* directory dentry if set. If this parameter is NULL, then the
|
|
* directory will be created in the root of the debugfs filesystem.
|
|
*
|
|
* This function creates a directory in debugfs with the given name.
|
|
*
|
|
* This function will return a pointer to a dentry if it succeeds. This
|
|
* pointer must be passed to the debugfs_remove() function when the file is
|
|
* to be removed (no automatic cleanup happens if your module is unloaded,
|
|
* you are responsible here.) If an error occurs, %NULL will be returned.
|
|
*
|
|
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
|
|
* returned.
|
|
*/
|
|
struct dentry *debugfs_create_dir(const char *name, struct dentry *parent)
|
|
{
|
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struct dentry *dentry = start_creating(name, parent);
|
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struct inode *inode;
|
|
|
|
if (IS_ERR(dentry))
|
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return NULL;
|
|
|
|
inode = debugfs_get_inode(dentry->d_sb);
|
|
if (unlikely(!inode))
|
|
return failed_creating(dentry);
|
|
|
|
inode->i_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO;
|
|
inode->i_op = &simple_dir_inode_operations;
|
|
inode->i_fop = &simple_dir_operations;
|
|
|
|
/* directory inodes start off with i_nlink == 2 (for "." entry) */
|
|
inc_nlink(inode);
|
|
d_instantiate(dentry, inode);
|
|
inc_nlink(d_inode(dentry->d_parent));
|
|
fsnotify_mkdir(d_inode(dentry->d_parent), dentry);
|
|
return end_creating(dentry);
|
|
}
|
|
EXPORT_SYMBOL_GPL(debugfs_create_dir);
|
|
|
|
/**
|
|
* debugfs_create_automount - create automount point in the debugfs filesystem
|
|
* @name: a pointer to a string containing the name of the file to create.
|
|
* @parent: a pointer to the parent dentry for this file. This should be a
|
|
* directory dentry if set. If this parameter is NULL, then the
|
|
* file will be created in the root of the debugfs filesystem.
|
|
* @f: function to be called when pathname resolution steps on that one.
|
|
* @data: opaque argument to pass to f().
|
|
*
|
|
* @f should return what ->d_automount() would.
|
|
*/
|
|
struct dentry *debugfs_create_automount(const char *name,
|
|
struct dentry *parent,
|
|
struct vfsmount *(*f)(void *),
|
|
void *data)
|
|
{
|
|
struct dentry *dentry = start_creating(name, parent);
|
|
struct inode *inode;
|
|
|
|
if (IS_ERR(dentry))
|
|
return NULL;
|
|
|
|
inode = debugfs_get_inode(dentry->d_sb);
|
|
if (unlikely(!inode))
|
|
return failed_creating(dentry);
|
|
|
|
inode->i_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO;
|
|
inode->i_flags |= S_AUTOMOUNT;
|
|
inode->i_private = data;
|
|
dentry->d_fsdata = (void *)f;
|
|
d_instantiate(dentry, inode);
|
|
return end_creating(dentry);
|
|
}
|
|
EXPORT_SYMBOL(debugfs_create_automount);
|
|
|
|
/**
|
|
* debugfs_create_symlink- create a symbolic link in the debugfs filesystem
|
|
* @name: a pointer to a string containing the name of the symbolic link to
|
|
* create.
|
|
* @parent: a pointer to the parent dentry for this symbolic link. This
|
|
* should be a directory dentry if set. If this parameter is NULL,
|
|
* then the symbolic link will be created in the root of the debugfs
|
|
* filesystem.
|
|
* @target: a pointer to a string containing the path to the target of the
|
|
* symbolic link.
|
|
*
|
|
* This function creates a symbolic link with the given name in debugfs that
|
|
* links to the given target path.
|
|
*
|
|
* This function will return a pointer to a dentry if it succeeds. This
|
|
* pointer must be passed to the debugfs_remove() function when the symbolic
|
|
* link is to be removed (no automatic cleanup happens if your module is
|
|
* unloaded, you are responsible here.) If an error occurs, %NULL will be
|
|
* returned.
|
|
*
|
|
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
|
|
* returned.
|
|
*/
|
|
struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
|
|
const char *target)
|
|
{
|
|
struct dentry *dentry;
|
|
struct inode *inode;
|
|
char *link = kstrdup(target, GFP_KERNEL);
|
|
if (!link)
|
|
return NULL;
|
|
|
|
dentry = start_creating(name, parent);
|
|
if (IS_ERR(dentry)) {
|
|
kfree(link);
|
|
return NULL;
|
|
}
|
|
|
|
inode = debugfs_get_inode(dentry->d_sb);
|
|
if (unlikely(!inode)) {
|
|
kfree(link);
|
|
return failed_creating(dentry);
|
|
}
|
|
inode->i_mode = S_IFLNK | S_IRWXUGO;
|
|
inode->i_op = &debugfs_link_operations;
|
|
inode->i_private = link;
|
|
d_instantiate(dentry, inode);
|
|
return end_creating(dentry);
|
|
}
|
|
EXPORT_SYMBOL_GPL(debugfs_create_symlink);
|
|
|
|
static int __debugfs_remove(struct dentry *dentry, struct dentry *parent)
|
|
{
|
|
int ret = 0;
|
|
|
|
if (debugfs_positive(dentry)) {
|
|
dget(dentry);
|
|
if (d_is_dir(dentry))
|
|
ret = simple_rmdir(d_inode(parent), dentry);
|
|
else
|
|
simple_unlink(d_inode(parent), dentry);
|
|
if (!ret)
|
|
d_delete(dentry);
|
|
dput(dentry);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* debugfs_remove - removes a file or directory from the debugfs filesystem
|
|
* @dentry: a pointer to a the dentry of the file or directory to be
|
|
* removed.
|
|
*
|
|
* This function removes a file or directory in debugfs that was previously
|
|
* created with a call to another debugfs function (like
|
|
* debugfs_create_file() or variants thereof.)
|
|
*
|
|
* This function is required to be called in order for the file to be
|
|
* removed, no automatic cleanup of files will happen when a module is
|
|
* removed, you are responsible here.
|
|
*/
|
|
void debugfs_remove(struct dentry *dentry)
|
|
{
|
|
struct dentry *parent;
|
|
int ret;
|
|
|
|
if (IS_ERR_OR_NULL(dentry))
|
|
return;
|
|
|
|
parent = dentry->d_parent;
|
|
if (!parent || d_really_is_negative(parent))
|
|
return;
|
|
|
|
mutex_lock(&d_inode(parent)->i_mutex);
|
|
ret = __debugfs_remove(dentry, parent);
|
|
mutex_unlock(&d_inode(parent)->i_mutex);
|
|
if (!ret)
|
|
simple_release_fs(&debugfs_mount, &debugfs_mount_count);
|
|
}
|
|
EXPORT_SYMBOL_GPL(debugfs_remove);
|
|
|
|
/**
|
|
* debugfs_remove_recursive - recursively removes a directory
|
|
* @dentry: a pointer to a the dentry of the directory to be removed.
|
|
*
|
|
* This function recursively removes a directory tree in debugfs that
|
|
* was previously created with a call to another debugfs function
|
|
* (like debugfs_create_file() or variants thereof.)
|
|
*
|
|
* This function is required to be called in order for the file to be
|
|
* removed, no automatic cleanup of files will happen when a module is
|
|
* removed, you are responsible here.
|
|
*/
|
|
void debugfs_remove_recursive(struct dentry *dentry)
|
|
{
|
|
struct dentry *child, *parent;
|
|
|
|
if (IS_ERR_OR_NULL(dentry))
|
|
return;
|
|
|
|
parent = dentry->d_parent;
|
|
if (!parent || d_really_is_negative(parent))
|
|
return;
|
|
|
|
parent = dentry;
|
|
down:
|
|
mutex_lock(&d_inode(parent)->i_mutex);
|
|
loop:
|
|
/*
|
|
* The parent->d_subdirs is protected by the d_lock. Outside that
|
|
* lock, the child can be unlinked and set to be freed which can
|
|
* use the d_u.d_child as the rcu head and corrupt this list.
|
|
*/
|
|
spin_lock(&parent->d_lock);
|
|
list_for_each_entry(child, &parent->d_subdirs, d_child) {
|
|
if (!debugfs_positive(child))
|
|
continue;
|
|
|
|
/* perhaps simple_empty(child) makes more sense */
|
|
if (!list_empty(&child->d_subdirs)) {
|
|
spin_unlock(&parent->d_lock);
|
|
mutex_unlock(&d_inode(parent)->i_mutex);
|
|
parent = child;
|
|
goto down;
|
|
}
|
|
|
|
spin_unlock(&parent->d_lock);
|
|
|
|
if (!__debugfs_remove(child, parent))
|
|
simple_release_fs(&debugfs_mount, &debugfs_mount_count);
|
|
|
|
/*
|
|
* The parent->d_lock protects agaist child from unlinking
|
|
* from d_subdirs. When releasing the parent->d_lock we can
|
|
* no longer trust that the next pointer is valid.
|
|
* Restart the loop. We'll skip this one with the
|
|
* debugfs_positive() check.
|
|
*/
|
|
goto loop;
|
|
}
|
|
spin_unlock(&parent->d_lock);
|
|
|
|
mutex_unlock(&d_inode(parent)->i_mutex);
|
|
child = parent;
|
|
parent = parent->d_parent;
|
|
mutex_lock(&d_inode(parent)->i_mutex);
|
|
|
|
if (child != dentry)
|
|
/* go up */
|
|
goto loop;
|
|
|
|
if (!__debugfs_remove(child, parent))
|
|
simple_release_fs(&debugfs_mount, &debugfs_mount_count);
|
|
mutex_unlock(&d_inode(parent)->i_mutex);
|
|
}
|
|
EXPORT_SYMBOL_GPL(debugfs_remove_recursive);
|
|
|
|
/**
|
|
* debugfs_rename - rename a file/directory in the debugfs filesystem
|
|
* @old_dir: a pointer to the parent dentry for the renamed object. This
|
|
* should be a directory dentry.
|
|
* @old_dentry: dentry of an object to be renamed.
|
|
* @new_dir: a pointer to the parent dentry where the object should be
|
|
* moved. This should be a directory dentry.
|
|
* @new_name: a pointer to a string containing the target name.
|
|
*
|
|
* This function renames a file/directory in debugfs. The target must not
|
|
* exist for rename to succeed.
|
|
*
|
|
* This function will return a pointer to old_dentry (which is updated to
|
|
* reflect renaming) if it succeeds. If an error occurs, %NULL will be
|
|
* returned.
|
|
*
|
|
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
|
|
* returned.
|
|
*/
|
|
struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
|
|
struct dentry *new_dir, const char *new_name)
|
|
{
|
|
int error;
|
|
struct dentry *dentry = NULL, *trap;
|
|
const char *old_name;
|
|
|
|
trap = lock_rename(new_dir, old_dir);
|
|
/* Source or destination directories don't exist? */
|
|
if (d_really_is_negative(old_dir) || d_really_is_negative(new_dir))
|
|
goto exit;
|
|
/* Source does not exist, cyclic rename, or mountpoint? */
|
|
if (d_really_is_negative(old_dentry) || old_dentry == trap ||
|
|
d_mountpoint(old_dentry))
|
|
goto exit;
|
|
dentry = lookup_one_len(new_name, new_dir, strlen(new_name));
|
|
/* Lookup failed, cyclic rename or target exists? */
|
|
if (IS_ERR(dentry) || dentry == trap || d_really_is_positive(dentry))
|
|
goto exit;
|
|
|
|
old_name = fsnotify_oldname_init(old_dentry->d_name.name);
|
|
|
|
error = simple_rename(d_inode(old_dir), old_dentry, d_inode(new_dir),
|
|
dentry);
|
|
if (error) {
|
|
fsnotify_oldname_free(old_name);
|
|
goto exit;
|
|
}
|
|
d_move(old_dentry, dentry);
|
|
fsnotify_move(d_inode(old_dir), d_inode(new_dir), old_name,
|
|
d_is_dir(old_dentry),
|
|
NULL, old_dentry);
|
|
fsnotify_oldname_free(old_name);
|
|
unlock_rename(new_dir, old_dir);
|
|
dput(dentry);
|
|
return old_dentry;
|
|
exit:
|
|
if (dentry && !IS_ERR(dentry))
|
|
dput(dentry);
|
|
unlock_rename(new_dir, old_dir);
|
|
return NULL;
|
|
}
|
|
EXPORT_SYMBOL_GPL(debugfs_rename);
|
|
|
|
/**
|
|
* debugfs_initialized - Tells whether debugfs has been registered
|
|
*/
|
|
bool debugfs_initialized(void)
|
|
{
|
|
return debugfs_registered;
|
|
}
|
|
EXPORT_SYMBOL_GPL(debugfs_initialized);
|
|
|
|
|
|
static struct kobject *debug_kobj;
|
|
|
|
static int __init debugfs_init(void)
|
|
{
|
|
int retval;
|
|
|
|
debug_kobj = kobject_create_and_add("debug", kernel_kobj);
|
|
if (!debug_kobj)
|
|
return -EINVAL;
|
|
|
|
retval = register_filesystem(&debug_fs_type);
|
|
if (retval)
|
|
kobject_put(debug_kobj);
|
|
else
|
|
debugfs_registered = true;
|
|
|
|
return retval;
|
|
}
|
|
core_initcall(debugfs_init);
|
|
|