linux_dsm_epyc7002/fs/cifs/cifsfs.h
Mateusz Guzik 24261fc23d cifs: delay super block destruction until all cifsFileInfo objects are gone
cifsFileInfo objects hold references to dentries and it is possible that
these will still be around in workqueues when VFS decides to kill super
block during unmount.

This results in panics like this one:
BUG: Dentry ffff88001f5e76c0{i=66b4a,n=1M-2} still in use (1) [unmount of cifs cifs]
------------[ cut here ]------------
kernel BUG at fs/dcache.c:943!
[..]
Process umount (pid: 1781, threadinfo ffff88003d6e8000, task ffff880035eeaec0)
[..]
Call Trace:
 [<ffffffff811b44f3>] shrink_dcache_for_umount+0x33/0x60
 [<ffffffff8119f7fc>] generic_shutdown_super+0x2c/0xe0
 [<ffffffff8119f946>] kill_anon_super+0x16/0x30
 [<ffffffffa036623a>] cifs_kill_sb+0x1a/0x30 [cifs]
 [<ffffffff8119fcc7>] deactivate_locked_super+0x57/0x80
 [<ffffffff811a085e>] deactivate_super+0x4e/0x70
 [<ffffffff811bb417>] mntput_no_expire+0xd7/0x130
 [<ffffffff811bc30c>] sys_umount+0x9c/0x3c0
 [<ffffffff81657c19>] system_call_fastpath+0x16/0x1b

Fix this by making each cifsFileInfo object hold a reference to cifs
super block, which implicitly keeps VFS super block around as well.

Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Cc: <stable@vger.kernel.org>
Reported-and-Tested-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2013-03-13 14:12:06 -05:00

137 lines
5.9 KiB
C

/*
* fs/cifs/cifsfs.h
*
* Copyright (c) International Business Machines Corp., 2002, 2007
* Author(s): Steve French (sfrench@us.ibm.com)
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef _CIFSFS_H
#define _CIFSFS_H
#define ROOT_I 2
/*
* ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down
* so that it will fit.
*/
static inline ino_t
cifs_uniqueid_to_ino_t(u64 fileid)
{
ino_t ino = (ino_t) fileid;
if (sizeof(ino_t) < sizeof(u64))
ino ^= fileid >> (sizeof(u64)-sizeof(ino_t)) * 8;
return ino;
}
extern struct file_system_type cifs_fs_type;
extern const struct address_space_operations cifs_addr_ops;
extern const struct address_space_operations cifs_addr_ops_smallbuf;
/* Functions related to super block operations */
extern void cifs_sb_active(struct super_block *sb);
extern void cifs_sb_deactive(struct super_block *sb);
/* Functions related to inodes */
extern const struct inode_operations cifs_dir_inode_ops;
extern struct inode *cifs_root_iget(struct super_block *);
extern int cifs_create(struct inode *, struct dentry *, umode_t,
bool excl);
extern int cifs_atomic_open(struct inode *, struct dentry *,
struct file *, unsigned, umode_t,
int *);
extern struct dentry *cifs_lookup(struct inode *, struct dentry *,
unsigned int);
extern int cifs_unlink(struct inode *dir, struct dentry *dentry);
extern int cifs_hardlink(struct dentry *, struct inode *, struct dentry *);
extern int cifs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
extern int cifs_mkdir(struct inode *, struct dentry *, umode_t);
extern int cifs_rmdir(struct inode *, struct dentry *);
extern int cifs_rename(struct inode *, struct dentry *, struct inode *,
struct dentry *);
extern int cifs_revalidate_file_attr(struct file *filp);
extern int cifs_revalidate_dentry_attr(struct dentry *);
extern int cifs_revalidate_file(struct file *filp);
extern int cifs_revalidate_dentry(struct dentry *);
extern int cifs_invalidate_mapping(struct inode *inode);
extern int cifs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
extern int cifs_setattr(struct dentry *, struct iattr *);
extern const struct inode_operations cifs_file_inode_ops;
extern const struct inode_operations cifs_symlink_inode_ops;
extern const struct inode_operations cifs_dfs_referral_inode_operations;
/* Functions related to files and directories */
extern const struct file_operations cifs_file_ops;
extern const struct file_operations cifs_file_direct_ops; /* if directio mnt */
extern const struct file_operations cifs_file_strict_ops; /* if strictio mnt */
extern const struct file_operations cifs_file_nobrl_ops; /* no brlocks */
extern const struct file_operations cifs_file_direct_nobrl_ops;
extern const struct file_operations cifs_file_strict_nobrl_ops;
extern int cifs_open(struct inode *inode, struct file *file);
extern int cifs_close(struct inode *inode, struct file *file);
extern int cifs_closedir(struct inode *inode, struct file *file);
extern ssize_t cifs_user_readv(struct kiocb *iocb, const struct iovec *iov,
unsigned long nr_segs, loff_t pos);
extern ssize_t cifs_strict_readv(struct kiocb *iocb, const struct iovec *iov,
unsigned long nr_segs, loff_t pos);
extern ssize_t cifs_user_writev(struct kiocb *iocb, const struct iovec *iov,
unsigned long nr_segs, loff_t pos);
extern ssize_t cifs_strict_writev(struct kiocb *iocb, const struct iovec *iov,
unsigned long nr_segs, loff_t pos);
extern int cifs_lock(struct file *, int, struct file_lock *);
extern int cifs_fsync(struct file *, loff_t, loff_t, int);
extern int cifs_strict_fsync(struct file *, loff_t, loff_t, int);
extern int cifs_flush(struct file *, fl_owner_t id);
extern int cifs_file_mmap(struct file * , struct vm_area_struct *);
extern int cifs_file_strict_mmap(struct file * , struct vm_area_struct *);
extern const struct file_operations cifs_dir_ops;
extern int cifs_dir_open(struct inode *inode, struct file *file);
extern int cifs_readdir(struct file *file, void *direntry, filldir_t filldir);
/* Functions related to dir entries */
extern const struct dentry_operations cifs_dentry_ops;
extern const struct dentry_operations cifs_ci_dentry_ops;
#ifdef CONFIG_CIFS_DFS_UPCALL
extern struct vfsmount *cifs_dfs_d_automount(struct path *path);
#else
#define cifs_dfs_d_automount NULL
#endif
/* Functions related to symlinks */
extern void *cifs_follow_link(struct dentry *direntry, struct nameidata *nd);
extern void cifs_put_link(struct dentry *direntry,
struct nameidata *nd, void *);
extern int cifs_readlink(struct dentry *direntry, char __user *buffer,
int buflen);
extern int cifs_symlink(struct inode *inode, struct dentry *direntry,
const char *symname);
extern int cifs_removexattr(struct dentry *, const char *);
extern int cifs_setxattr(struct dentry *, const char *, const void *,
size_t, int);
extern ssize_t cifs_getxattr(struct dentry *, const char *, void *, size_t);
extern ssize_t cifs_listxattr(struct dentry *, char *, size_t);
extern long cifs_ioctl(struct file *filep, unsigned int cmd, unsigned long arg);
#ifdef CONFIG_CIFS_NFSD_EXPORT
extern const struct export_operations cifs_export_ops;
#endif /* CONFIG_CIFS_NFSD_EXPORT */
#define CIFS_VERSION "2.0"
#endif /* _CIFSFS_H */