mirror_zfs/include/sys/zfs_znode.h
Tom Caputi e7a2fa70c3 Fix deadlock in 'zfs rollback'
Currently, the 'zfs rollback' code can end up deadlocked due to
the way the kernel handles unreferenced inodes on a suspended fs.
Essentially, the zfs_resume_fs() code path may cause zfs to spawn
new threads as it reinstantiates the suspended fs's zil. When a
new thread is spawned, the kernel may attempt to free memory for
that thread by freeing some unreferenced inodes. If it happens to
select inodes that are a a part of the suspended fs a deadlock
will occur because freeing inodes requires holding the fs's
z_teardown_inactive_lock which is still held from the suspend.

This patch corrects this issue by adding an additional reference
to all inodes that are still present when a suspend is initiated.
This prevents them from being freed by the kernel for any reason.

Reviewed-by: Alek Pinchuk <apinchuk@datto.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Closes #9203
2019-08-27 09:55:51 -07:00

413 lines
15 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2012, 2018 by Delphix. All rights reserved.
* Copyright 2016 Nexenta Systems, Inc. All rights reserved.
*/
#ifndef _SYS_FS_ZFS_ZNODE_H
#define _SYS_FS_ZFS_ZNODE_H
#ifdef _KERNEL
#include <sys/isa_defs.h>
#include <sys/types32.h>
#include <sys/list.h>
#include <sys/dmu.h>
#include <sys/sa.h>
#include <sys/zfs_vfsops.h>
#include <sys/rrwlock.h>
#include <sys/zfs_sa.h>
#include <sys/zfs_stat.h>
#include <sys/zfs_rlock.h>
#endif
#include <sys/zfs_acl.h>
#include <sys/zil.h>
#include <sys/zfs_project.h>
#ifdef __cplusplus
extern "C" {
#endif
/*
* Additional file level attributes, that are stored
* in the upper half of zp_flags
*/
#define ZFS_READONLY 0x0000000100000000ull
#define ZFS_HIDDEN 0x0000000200000000ull
#define ZFS_SYSTEM 0x0000000400000000ull
#define ZFS_ARCHIVE 0x0000000800000000ull
#define ZFS_IMMUTABLE 0x0000001000000000ull
#define ZFS_NOUNLINK 0x0000002000000000ull
#define ZFS_APPENDONLY 0x0000004000000000ull
#define ZFS_NODUMP 0x0000008000000000ull
#define ZFS_OPAQUE 0x0000010000000000ull
#define ZFS_AV_QUARANTINED 0x0000020000000000ull
#define ZFS_AV_MODIFIED 0x0000040000000000ull
#define ZFS_REPARSE 0x0000080000000000ull
#define ZFS_OFFLINE 0x0000100000000000ull
#define ZFS_SPARSE 0x0000200000000000ull
/*
* PROJINHERIT attribute is used to indicate that the child object under the
* directory which has the PROJINHERIT attribute needs to inherit its parent
* project ID that is used by project quota.
*/
#define ZFS_PROJINHERIT 0x0000400000000000ull
/*
* PROJID attr is used internally to indicate that the object has project ID.
*/
#define ZFS_PROJID 0x0000800000000000ull
#define ZFS_ATTR_SET(zp, attr, value, pflags, tx) \
{ \
if (value) \
pflags |= attr; \
else \
pflags &= ~attr; \
VERIFY(0 == sa_update(zp->z_sa_hdl, SA_ZPL_FLAGS(ZTOZSB(zp)), \
&pflags, sizeof (pflags), tx)); \
}
/*
* Define special zfs pflags
*/
#define ZFS_XATTR 0x1 /* is an extended attribute */
#define ZFS_INHERIT_ACE 0x2 /* ace has inheritable ACEs */
#define ZFS_ACL_TRIVIAL 0x4 /* files ACL is trivial */
#define ZFS_ACL_OBJ_ACE 0x8 /* ACL has CMPLX Object ACE */
#define ZFS_ACL_PROTECTED 0x10 /* ACL protected */
#define ZFS_ACL_DEFAULTED 0x20 /* ACL should be defaulted */
#define ZFS_ACL_AUTO_INHERIT 0x40 /* ACL should be inherited */
#define ZFS_BONUS_SCANSTAMP 0x80 /* Scanstamp in bonus area */
#define ZFS_NO_EXECS_DENIED 0x100 /* exec was given to everyone */
#define SA_ZPL_ATIME(z) z->z_attr_table[ZPL_ATIME]
#define SA_ZPL_MTIME(z) z->z_attr_table[ZPL_MTIME]
#define SA_ZPL_CTIME(z) z->z_attr_table[ZPL_CTIME]
#define SA_ZPL_CRTIME(z) z->z_attr_table[ZPL_CRTIME]
#define SA_ZPL_GEN(z) z->z_attr_table[ZPL_GEN]
#define SA_ZPL_DACL_ACES(z) z->z_attr_table[ZPL_DACL_ACES]
#define SA_ZPL_XATTR(z) z->z_attr_table[ZPL_XATTR]
#define SA_ZPL_SYMLINK(z) z->z_attr_table[ZPL_SYMLINK]
#define SA_ZPL_RDEV(z) z->z_attr_table[ZPL_RDEV]
#define SA_ZPL_SCANSTAMP(z) z->z_attr_table[ZPL_SCANSTAMP]
#define SA_ZPL_UID(z) z->z_attr_table[ZPL_UID]
#define SA_ZPL_GID(z) z->z_attr_table[ZPL_GID]
#define SA_ZPL_PARENT(z) z->z_attr_table[ZPL_PARENT]
#define SA_ZPL_LINKS(z) z->z_attr_table[ZPL_LINKS]
#define SA_ZPL_MODE(z) z->z_attr_table[ZPL_MODE]
#define SA_ZPL_DACL_COUNT(z) z->z_attr_table[ZPL_DACL_COUNT]
#define SA_ZPL_FLAGS(z) z->z_attr_table[ZPL_FLAGS]
#define SA_ZPL_SIZE(z) z->z_attr_table[ZPL_SIZE]
#define SA_ZPL_ZNODE_ACL(z) z->z_attr_table[ZPL_ZNODE_ACL]
#define SA_ZPL_DXATTR(z) z->z_attr_table[ZPL_DXATTR]
#define SA_ZPL_PAD(z) z->z_attr_table[ZPL_PAD]
#define SA_ZPL_PROJID(z) z->z_attr_table[ZPL_PROJID]
/*
* Is ID ephemeral?
*/
#define IS_EPHEMERAL(x) (x > MAXUID)
/*
* Should we use FUIDs?
*/
#define USE_FUIDS(version, os) (version >= ZPL_VERSION_FUID && \
spa_version(dmu_objset_spa(os)) >= SPA_VERSION_FUID)
#define USE_SA(version, os) (version >= ZPL_VERSION_SA && \
spa_version(dmu_objset_spa(os)) >= SPA_VERSION_SA)
#define MASTER_NODE_OBJ 1
/*
* Special attributes for master node.
* "userquota@", "groupquota@" and "projectquota@" are also valid (from
* zfs_userquota_prop_prefixes[]).
*/
#define ZFS_FSID "FSID"
#define ZFS_UNLINKED_SET "DELETE_QUEUE"
#define ZFS_ROOT_OBJ "ROOT"
#define ZPL_VERSION_STR "VERSION"
#define ZFS_FUID_TABLES "FUID"
#define ZFS_SHARES_DIR "SHARES"
#define ZFS_SA_ATTRS "SA_ATTRS"
/*
* Convert mode bits (zp_mode) to BSD-style DT_* values for storing in
* the directory entries. On Linux systems this value is already
* defined correctly as part of the /usr/include/dirent.h header file.
*/
#ifndef IFTODT
#define IFTODT(mode) (((mode) & S_IFMT) >> 12)
#endif
/*
* The directory entry has the type (currently unused on Solaris) in the
* top 4 bits, and the object number in the low 48 bits. The "middle"
* 12 bits are unused.
*/
#define ZFS_DIRENT_TYPE(de) BF64_GET(de, 60, 4)
#define ZFS_DIRENT_OBJ(de) BF64_GET(de, 0, 48)
/*
* Directory entry locks control access to directory entries.
* They are used to protect creates, deletes, and renames.
* Each directory znode has a mutex and a list of locked names.
*/
#ifdef _KERNEL
typedef struct zfs_dirlock {
char *dl_name; /* directory entry being locked */
uint32_t dl_sharecnt; /* 0 if exclusive, > 0 if shared */
uint8_t dl_namelock; /* 1 if z_name_lock is NOT held */
uint16_t dl_namesize; /* set if dl_name was allocated */
kcondvar_t dl_cv; /* wait for entry to be unlocked */
struct znode *dl_dzp; /* directory znode */
struct zfs_dirlock *dl_next; /* next in z_dirlocks list */
} zfs_dirlock_t;
typedef struct znode {
uint64_t z_id; /* object ID for this znode */
kmutex_t z_lock; /* znode modification lock */
krwlock_t z_parent_lock; /* parent lock for directories */
krwlock_t z_name_lock; /* "master" lock for dirent locks */
zfs_dirlock_t *z_dirlocks; /* directory entry lock list */
rangelock_t z_rangelock; /* file range locks */
boolean_t z_unlinked; /* file has been unlinked */
boolean_t z_atime_dirty; /* atime needs to be synced */
boolean_t z_zn_prefetch; /* Prefetch znodes? */
boolean_t z_moved; /* Has this znode been moved? */
boolean_t z_is_sa; /* are we native sa? */
boolean_t z_is_mapped; /* are we mmap'ed */
boolean_t z_is_ctldir; /* are we .zfs entry */
boolean_t z_is_stale; /* are we stale due to rollback? */
boolean_t z_suspended; /* extra ref from a suspend? */
uint_t z_blksz; /* block size in bytes */
uint_t z_seq; /* modification sequence number */
uint64_t z_mapcnt; /* number of pages mapped to file */
uint64_t z_dnodesize; /* dnode size */
uint64_t z_size; /* file size (cached) */
uint64_t z_pflags; /* pflags (cached) */
uint32_t z_sync_cnt; /* synchronous open count */
mode_t z_mode; /* mode (cached) */
kmutex_t z_acl_lock; /* acl data lock */
zfs_acl_t *z_acl_cached; /* cached acl */
krwlock_t z_xattr_lock; /* xattr data lock */
nvlist_t *z_xattr_cached; /* cached xattrs */
uint64_t z_xattr_parent; /* parent obj for this xattr */
uint64_t z_projid; /* project ID */
list_node_t z_link_node; /* all znodes in fs link */
sa_handle_t *z_sa_hdl; /* handle to sa data */
struct inode z_inode; /* generic vfs inode */
} znode_t;
typedef struct znode_hold {
uint64_t zh_obj; /* object id */
kmutex_t zh_lock; /* lock serializing object access */
avl_node_t zh_node; /* avl tree linkage */
zfs_refcount_t zh_refcount; /* active consumer reference count */
} znode_hold_t;
static inline uint64_t
zfs_inherit_projid(znode_t *dzp)
{
return ((dzp->z_pflags & ZFS_PROJINHERIT) ? dzp->z_projid :
ZFS_DEFAULT_PROJID);
}
/*
* Range locking rules
* --------------------
* 1. When truncating a file (zfs_create, zfs_setattr, zfs_space) the whole
* file range needs to be locked as RL_WRITER. Only then can the pages be
* freed etc and zp_size reset. zp_size must be set within range lock.
* 2. For writes and punching holes (zfs_write & zfs_space) just the range
* being written or freed needs to be locked as RL_WRITER.
* Multiple writes at the end of the file must coordinate zp_size updates
* to ensure data isn't lost. A compare and swap loop is currently used
* to ensure the file size is at least the offset last written.
* 3. For reads (zfs_read, zfs_get_data & zfs_putapage) just the range being
* read needs to be locked as RL_READER. A check against zp_size can then
* be made for reading beyond end of file.
*/
/*
* Convert between znode pointers and inode pointers
*/
#define ZTOI(znode) (&((znode)->z_inode))
#define ITOZ(inode) (container_of((inode), znode_t, z_inode))
#define ZTOZSB(znode) ((zfsvfs_t *)(ZTOI(znode)->i_sb->s_fs_info))
#define ITOZSB(inode) ((zfsvfs_t *)((inode)->i_sb->s_fs_info))
#define S_ISDEV(mode) (S_ISCHR(mode) || S_ISBLK(mode) || S_ISFIFO(mode))
/* Called on entry to each ZFS inode and vfs operation. */
#define ZFS_ENTER_ERROR(zfsvfs, error) \
do { \
rrm_enter_read(&(zfsvfs)->z_teardown_lock, FTAG); \
if ((zfsvfs)->z_unmounted) { \
ZFS_EXIT(zfsvfs); \
return (error); \
} \
} while (0)
#define ZFS_ENTER(zfsvfs) ZFS_ENTER_ERROR(zfsvfs, EIO)
#define ZPL_ENTER(zfsvfs) ZFS_ENTER_ERROR(zfsvfs, -EIO)
/* Must be called before exiting the operation. */
#define ZFS_EXIT(zfsvfs) \
do { \
rrm_exit(&(zfsvfs)->z_teardown_lock, FTAG); \
} while (0)
#define ZPL_EXIT(zfsvfs) ZFS_EXIT(zfsvfs)
/* Verifies the znode is valid. */
#define ZFS_VERIFY_ZP_ERROR(zp, error) \
do { \
if ((zp)->z_sa_hdl == NULL) { \
ZFS_EXIT(ZTOZSB(zp)); \
return (error); \
} \
} while (0)
#define ZFS_VERIFY_ZP(zp) ZFS_VERIFY_ZP_ERROR(zp, EIO)
#define ZPL_VERIFY_ZP(zp) ZFS_VERIFY_ZP_ERROR(zp, -EIO)
/*
* Macros for dealing with dmu_buf_hold
*/
#define ZFS_OBJ_MTX_SZ 64
#define ZFS_OBJ_MTX_MAX (1024 * 1024)
#define ZFS_OBJ_HASH(zfsvfs, obj) ((obj) & ((zfsvfs->z_hold_size) - 1))
extern unsigned int zfs_object_mutex_size;
/*
* Encode ZFS stored time values from a struct timespec / struct timespec64.
*/
#define ZFS_TIME_ENCODE(tp, stmp) \
do { \
(stmp)[0] = (uint64_t)(tp)->tv_sec; \
(stmp)[1] = (uint64_t)(tp)->tv_nsec; \
} while (0)
#if defined(HAVE_INODE_TIMESPEC64_TIMES)
/*
* Decode ZFS stored time values to a struct timespec64
* 4.18 and newer kernels.
*/
#define ZFS_TIME_DECODE(tp, stmp) \
do { \
(tp)->tv_sec = (time64_t)(stmp)[0]; \
(tp)->tv_nsec = (long)(stmp)[1]; \
} while (0)
#else
/*
* Decode ZFS stored time values to a struct timespec
* 4.17 and older kernels.
*/
#define ZFS_TIME_DECODE(tp, stmp) \
do { \
(tp)->tv_sec = (time_t)(stmp)[0]; \
(tp)->tv_nsec = (long)(stmp)[1]; \
} while (0)
#endif /* HAVE_INODE_TIMESPEC64_TIMES */
/*
* Timestamp defines
*/
#define ACCESSED (ATTR_ATIME)
#define STATE_CHANGED (ATTR_CTIME)
#define CONTENT_MODIFIED (ATTR_MTIME | ATTR_CTIME)
extern int zfs_init_fs(zfsvfs_t *, znode_t **);
extern void zfs_set_dataprop(objset_t *);
extern void zfs_create_fs(objset_t *os, cred_t *cr, nvlist_t *,
dmu_tx_t *tx);
extern void zfs_tstamp_update_setup(znode_t *, uint_t, uint64_t [2],
uint64_t [2]);
extern void zfs_grow_blocksize(znode_t *, uint64_t, dmu_tx_t *);
extern int zfs_freesp(znode_t *, uint64_t, uint64_t, int, boolean_t);
extern void zfs_znode_init(void);
extern void zfs_znode_fini(void);
extern int zfs_znode_hold_compare(const void *, const void *);
extern int zfs_zget(zfsvfs_t *, uint64_t, znode_t **);
extern int zfs_rezget(znode_t *);
extern void zfs_zinactive(znode_t *);
extern void zfs_znode_delete(znode_t *, dmu_tx_t *);
extern void zfs_remove_op_tables(void);
extern int zfs_create_op_tables(void);
extern int zfs_sync(struct super_block *, int, cred_t *);
extern dev_t zfs_cmpldev(uint64_t);
extern int zfs_get_zplprop(objset_t *os, zfs_prop_t prop, uint64_t *value);
extern int zfs_get_stats(objset_t *os, nvlist_t *nv);
extern boolean_t zfs_get_vfs_flag_unmounted(objset_t *os);
extern void zfs_znode_dmu_fini(znode_t *);
extern int zfs_inode_alloc(struct super_block *, struct inode **ip);
extern void zfs_inode_destroy(struct inode *);
extern void zfs_inode_update(znode_t *);
extern void zfs_mark_inode_dirty(struct inode *);
extern boolean_t zfs_relatime_need_update(const struct inode *);
extern void zfs_log_create(zilog_t *zilog, dmu_tx_t *tx, uint64_t txtype,
znode_t *dzp, znode_t *zp, char *name, vsecattr_t *, zfs_fuid_info_t *,
vattr_t *vap);
extern int zfs_log_create_txtype(zil_create_t, vsecattr_t *vsecp,
vattr_t *vap);
extern void zfs_log_remove(zilog_t *zilog, dmu_tx_t *tx, uint64_t txtype,
znode_t *dzp, char *name, uint64_t foid, boolean_t unlinked);
#define ZFS_NO_OBJECT 0 /* no object id */
extern void zfs_log_link(zilog_t *zilog, dmu_tx_t *tx, uint64_t txtype,
znode_t *dzp, znode_t *zp, char *name);
extern void zfs_log_symlink(zilog_t *zilog, dmu_tx_t *tx, uint64_t txtype,
znode_t *dzp, znode_t *zp, char *name, char *link);
extern void zfs_log_rename(zilog_t *zilog, dmu_tx_t *tx, uint64_t txtype,
znode_t *sdzp, char *sname, znode_t *tdzp, char *dname, znode_t *szp);
extern void zfs_log_write(zilog_t *zilog, dmu_tx_t *tx, int txtype,
znode_t *zp, offset_t off, ssize_t len, int ioflag,
zil_callback_t callback, void *callback_data);
extern void zfs_log_truncate(zilog_t *zilog, dmu_tx_t *tx, int txtype,
znode_t *zp, uint64_t off, uint64_t len);
extern void zfs_log_setattr(zilog_t *zilog, dmu_tx_t *tx, int txtype,
znode_t *zp, vattr_t *vap, uint_t mask_applied, zfs_fuid_info_t *fuidp);
extern void zfs_log_acl(zilog_t *zilog, dmu_tx_t *tx, znode_t *zp,
vsecattr_t *vsecp, zfs_fuid_info_t *fuidp);
extern void zfs_xvattr_set(znode_t *zp, xvattr_t *xvap, dmu_tx_t *tx);
extern void zfs_upgrade(zfsvfs_t *zfsvfs, dmu_tx_t *tx);
#if defined(HAVE_UIO_RW)
extern caddr_t zfs_map_page(page_t *, enum seg_rw);
extern void zfs_unmap_page(page_t *, caddr_t);
#endif /* HAVE_UIO_RW */
extern zil_get_data_t zfs_get_data;
extern zil_replay_func_t *zfs_replay_vector[TX_MAX_TYPE];
extern int zfsfstype;
#endif /* _KERNEL */
extern int zfs_obj_to_path(objset_t *osp, uint64_t obj, char *buf, int len);
#ifdef __cplusplus
}
#endif
#endif /* _SYS_FS_ZFS_ZNODE_H */