xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/zfs_znode.h (revision e0d8bef656731559f2d1d5dca0077a6a66c6f8b9)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #ifndef	_SYS_FS_ZFS_ZNODE_H
27 #define	_SYS_FS_ZFS_ZNODE_H
28 
29 #ifdef _KERNEL
30 #include <sys/isa_defs.h>
31 #include <sys/types32.h>
32 #include <sys/attr.h>
33 #include <sys/list.h>
34 #include <sys/dmu.h>
35 #include <sys/zfs_vfsops.h>
36 #include <sys/rrwlock.h>
37 #endif
38 #include <sys/zfs_acl.h>
39 #include <sys/zil.h>
40 
41 #ifdef	__cplusplus
42 extern "C" {
43 #endif
44 
45 /*
46  * Additional file level attributes, that are stored
47  * in the upper half of zp_flags
48  */
49 #define	ZFS_READONLY		0x0000000100000000
50 #define	ZFS_HIDDEN		0x0000000200000000
51 #define	ZFS_SYSTEM		0x0000000400000000
52 #define	ZFS_ARCHIVE		0x0000000800000000
53 #define	ZFS_IMMUTABLE		0x0000001000000000
54 #define	ZFS_NOUNLINK		0x0000002000000000
55 #define	ZFS_APPENDONLY		0x0000004000000000
56 #define	ZFS_NODUMP		0x0000008000000000
57 #define	ZFS_OPAQUE		0x0000010000000000
58 #define	ZFS_AV_QUARANTINED 	0x0000020000000000
59 #define	ZFS_AV_MODIFIED 	0x0000040000000000
60 
61 #define	ZFS_ATTR_SET(zp, attr, value)	\
62 { \
63 	if (value) \
64 		zp->z_phys->zp_flags |= attr; \
65 	else \
66 		zp->z_phys->zp_flags &= ~attr; \
67 }
68 
69 /*
70  * Define special zfs pflags
71  */
72 #define	ZFS_XATTR		0x1		/* is an extended attribute */
73 #define	ZFS_INHERIT_ACE		0x2		/* ace has inheritable ACEs */
74 #define	ZFS_ACL_TRIVIAL 	0x4		/* files ACL is trivial */
75 #define	ZFS_ACL_OBJ_ACE 	0x8		/* ACL has CMPLX Object ACE */
76 #define	ZFS_ACL_PROTECTED	0x10		/* ACL protected */
77 #define	ZFS_ACL_DEFAULTED	0x20		/* ACL should be defaulted */
78 #define	ZFS_ACL_AUTO_INHERIT	0x40		/* ACL should be inherited */
79 #define	ZFS_BONUS_SCANSTAMP	0x80		/* Scanstamp in bonus area */
80 
81 /*
82  * Is ID ephemeral?
83  */
84 #define	IS_EPHEMERAL(x)		(x > MAXUID)
85 
86 /*
87  * Should we use FUIDs?
88  */
89 #define	USE_FUIDS(version, os)	(version >= ZPL_VERSION_FUID &&\
90     spa_version(dmu_objset_spa(os)) >= SPA_VERSION_FUID)
91 
92 #define	MASTER_NODE_OBJ	1
93 
94 /*
95  * Special attributes for master node.
96  */
97 #define	ZFS_FSID		"FSID"
98 #define	ZFS_UNLINKED_SET	"DELETE_QUEUE"
99 #define	ZFS_ROOT_OBJ		"ROOT"
100 #define	ZPL_VERSION_STR		"VERSION"
101 #define	ZFS_FUID_TABLES		"FUID"
102 
103 #define	ZFS_MAX_BLOCKSIZE	(SPA_MAXBLOCKSIZE)
104 
105 /* Path component length */
106 /*
107  * The generic fs code uses MAXNAMELEN to represent
108  * what the largest component length is.  Unfortunately,
109  * this length includes the terminating NULL.  ZFS needs
110  * to tell the users via pathconf() and statvfs() what the
111  * true maximum length of a component is, excluding the NULL.
112  */
113 #define	ZFS_MAXNAMELEN	(MAXNAMELEN - 1)
114 
115 /*
116  * Convert mode bits (zp_mode) to BSD-style DT_* values for storing in
117  * the directory entries.
118  */
119 #define	IFTODT(mode) (((mode) & S_IFMT) >> 12)
120 
121 /*
122  * The directory entry has the type (currently unused on Solaris) in the
123  * top 4 bits, and the object number in the low 48 bits.  The "middle"
124  * 12 bits are unused.
125  */
126 #define	ZFS_DIRENT_TYPE(de) BF64_GET(de, 60, 4)
127 #define	ZFS_DIRENT_OBJ(de) BF64_GET(de, 0, 48)
128 
129 /*
130  * This is the persistent portion of the znode.  It is stored
131  * in the "bonus buffer" of the file.  Short symbolic links
132  * are also stored in the bonus buffer.
133  */
134 typedef struct znode_phys {
135 	uint64_t zp_atime[2];		/*  0 - last file access time */
136 	uint64_t zp_mtime[2];		/* 16 - last file modification time */
137 	uint64_t zp_ctime[2];		/* 32 - last file change time */
138 	uint64_t zp_crtime[2];		/* 48 - creation time */
139 	uint64_t zp_gen;		/* 64 - generation (txg of creation) */
140 	uint64_t zp_mode;		/* 72 - file mode bits */
141 	uint64_t zp_size;		/* 80 - size of file */
142 	uint64_t zp_parent;		/* 88 - directory parent (`..') */
143 	uint64_t zp_links;		/* 96 - number of links to file */
144 	uint64_t zp_xattr;		/* 104 - DMU object for xattrs */
145 	uint64_t zp_rdev;		/* 112 - dev_t for VBLK & VCHR files */
146 	uint64_t zp_flags;		/* 120 - persistent flags */
147 	uint64_t zp_uid;		/* 128 - file owner */
148 	uint64_t zp_gid;		/* 136 - owning group */
149 	uint64_t zp_zap;		/* 144 - extra attributes */
150 	uint64_t zp_pad[3];		/* 152 - future */
151 	zfs_acl_phys_t zp_acl;		/* 176 - 263 ACL */
152 	/*
153 	 * Data may pad out any remaining bytes in the znode buffer, eg:
154 	 *
155 	 * |<---------------------- dnode_phys (512) ------------------------>|
156 	 * |<-- dnode (192) --->|<----------- "bonus" buffer (320) ---------->|
157 	 *			|<---- znode (264) ---->|<---- data (56) ---->|
158 	 *
159 	 * At present, we use this space for the following:
160 	 *  - symbolic links
161 	 *  - 32-byte anti-virus scanstamp (regular files only)
162 	 */
163 } znode_phys_t;
164 
165 /*
166  * Directory entry locks control access to directory entries.
167  * They are used to protect creates, deletes, and renames.
168  * Each directory znode has a mutex and a list of locked names.
169  */
170 #ifdef _KERNEL
171 typedef struct zfs_dirlock {
172 	char		*dl_name;	/* directory entry being locked */
173 	uint32_t	dl_sharecnt;	/* 0 if exclusive, > 0 if shared */
174 	uint16_t	dl_namesize;	/* set if dl_name was allocated */
175 	kcondvar_t	dl_cv;		/* wait for entry to be unlocked */
176 	struct znode	*dl_dzp;	/* directory znode */
177 	struct zfs_dirlock *dl_next;	/* next in z_dirlocks list */
178 } zfs_dirlock_t;
179 
180 typedef struct znode {
181 	struct zfsvfs	*z_zfsvfs;
182 	vnode_t		*z_vnode;
183 	uint64_t	z_id;		/* object ID for this znode */
184 	kmutex_t	z_lock;		/* znode modification lock */
185 	krwlock_t	z_parent_lock;	/* parent lock for directories */
186 	krwlock_t	z_name_lock;	/* "master" lock for dirent locks */
187 	zfs_dirlock_t	*z_dirlocks;	/* directory entry lock list */
188 	kmutex_t	z_range_lock;	/* protects changes to z_range_avl */
189 	avl_tree_t	z_range_avl;	/* avl tree of file range locks */
190 	uint8_t		z_unlinked;	/* file has been unlinked */
191 	uint8_t		z_atime_dirty;	/* atime needs to be synced */
192 	uint8_t		z_zn_prefetch;	/* Prefetch znodes? */
193 	uint_t		z_blksz;	/* block size in bytes */
194 	uint_t		z_seq;		/* modification sequence number */
195 	uint64_t	z_mapcnt;	/* number of pages mapped to file */
196 	uint64_t	z_last_itx;	/* last ZIL itx on this znode */
197 	uint64_t	z_gen;		/* generation (same as zp_gen) */
198 	uint32_t	z_sync_cnt;	/* synchronous open count */
199 	kmutex_t	z_acl_lock;	/* acl data lock */
200 	list_node_t	z_link_node;	/* all znodes in fs link */
201 	/*
202 	 * These are dmu managed fields.
203 	 */
204 	znode_phys_t	*z_phys;	/* pointer to persistent znode */
205 	dmu_buf_t	*z_dbuf;	/* buffer containing the z_phys */
206 } znode_t;
207 
208 
209 /*
210  * Range locking rules
211  * --------------------
212  * 1. When truncating a file (zfs_create, zfs_setattr, zfs_space) the whole
213  *    file range needs to be locked as RL_WRITER. Only then can the pages be
214  *    freed etc and zp_size reset. zp_size must be set within range lock.
215  * 2. For writes and punching holes (zfs_write & zfs_space) just the range
216  *    being written or freed needs to be locked as RL_WRITER.
217  *    Multiple writes at the end of the file must coordinate zp_size updates
218  *    to ensure data isn't lost. A compare and swap loop is currently used
219  *    to ensure the file size is at least the offset last written.
220  * 3. For reads (zfs_read, zfs_get_data & zfs_putapage) just the range being
221  *    read needs to be locked as RL_READER. A check against zp_size can then
222  *    be made for reading beyond end of file.
223  */
224 
225 /*
226  * Convert between znode pointers and vnode pointers
227  */
228 #define	ZTOV(ZP)	((ZP)->z_vnode)
229 #define	VTOZ(VP)	((znode_t *)(VP)->v_data)
230 
231 /*
232  * ZFS_ENTER() is called on entry to each ZFS vnode and vfs operation.
233  * ZFS_EXIT() must be called before exitting the vop.
234  * ZFS_VERIFY_ZP() verifies the znode is valid.
235  */
236 #define	ZFS_ENTER(zfsvfs) \
237 	{ \
238 		rrw_enter(&(zfsvfs)->z_teardown_lock, RW_READER, FTAG); \
239 		if ((zfsvfs)->z_unmounted) { \
240 			ZFS_EXIT(zfsvfs); \
241 			return (EIO); \
242 		} \
243 	}
244 
245 #define	ZFS_EXIT(zfsvfs) rrw_exit(&(zfsvfs)->z_teardown_lock, FTAG)
246 
247 #define	ZFS_VERIFY_ZP(zp) \
248 	if ((zp)->z_dbuf == NULL) { \
249 		ZFS_EXIT((zp)->z_zfsvfs); \
250 		return (EIO); \
251 	} \
252 
253 /*
254  * Macros for dealing with dmu_buf_hold
255  */
256 #define	ZFS_OBJ_HASH(obj_num)	((obj_num) & (ZFS_OBJ_MTX_SZ - 1))
257 #define	ZFS_OBJ_MUTEX(zfsvfs, obj_num)	\
258 	(&(zfsvfs)->z_hold_mtx[ZFS_OBJ_HASH(obj_num)])
259 #define	ZFS_OBJ_HOLD_ENTER(zfsvfs, obj_num) \
260 	mutex_enter(ZFS_OBJ_MUTEX((zfsvfs), (obj_num)))
261 #define	ZFS_OBJ_HOLD_TRYENTER(zfsvfs, obj_num) \
262 	mutex_tryenter(ZFS_OBJ_MUTEX((zfsvfs), (obj_num)))
263 #define	ZFS_OBJ_HOLD_EXIT(zfsvfs, obj_num) \
264 	mutex_exit(ZFS_OBJ_MUTEX((zfsvfs), (obj_num)))
265 
266 /*
267  * Macros to encode/decode ZFS stored time values from/to struct timespec
268  */
269 #define	ZFS_TIME_ENCODE(tp, stmp)		\
270 {						\
271 	(stmp)[0] = (uint64_t)(tp)->tv_sec;	\
272 	(stmp)[1] = (uint64_t)(tp)->tv_nsec;	\
273 }
274 
275 #define	ZFS_TIME_DECODE(tp, stmp)		\
276 {						\
277 	(tp)->tv_sec = (time_t)(stmp)[0];		\
278 	(tp)->tv_nsec = (long)(stmp)[1];		\
279 }
280 
281 /*
282  * Timestamp defines
283  */
284 #define	ACCESSED		(AT_ATIME)
285 #define	STATE_CHANGED		(AT_CTIME)
286 #define	CONTENT_MODIFIED	(AT_MTIME | AT_CTIME)
287 
288 #define	ZFS_ACCESSTIME_STAMP(zfsvfs, zp) \
289 	if ((zfsvfs)->z_atime && !((zfsvfs)->z_vfs->vfs_flag & VFS_RDONLY)) \
290 		zfs_time_stamper(zp, ACCESSED, NULL)
291 
292 extern int	zfs_init_fs(zfsvfs_t *, znode_t **);
293 extern void	zfs_set_dataprop(objset_t *);
294 extern void	zfs_create_fs(objset_t *os, cred_t *cr, nvlist_t *,
295     dmu_tx_t *tx);
296 extern void	zfs_time_stamper(znode_t *, uint_t, dmu_tx_t *);
297 extern void	zfs_time_stamper_locked(znode_t *, uint_t, dmu_tx_t *);
298 extern void	zfs_grow_blocksize(znode_t *, uint64_t, dmu_tx_t *);
299 extern int	zfs_freesp(znode_t *, uint64_t, uint64_t, int, boolean_t);
300 extern void	zfs_znode_init(void);
301 extern void	zfs_znode_fini(void);
302 extern int	zfs_zget(zfsvfs_t *, uint64_t, znode_t **);
303 extern int	zfs_rezget(znode_t *);
304 extern void	zfs_zinactive(znode_t *);
305 extern void	zfs_znode_delete(znode_t *, dmu_tx_t *);
306 extern void	zfs_znode_free(znode_t *);
307 extern void	zfs_remove_op_tables();
308 extern int	zfs_create_op_tables();
309 extern int	zfs_sync(vfs_t *vfsp, short flag, cred_t *cr);
310 extern dev_t	zfs_cmpldev(uint64_t);
311 extern int	zfs_get_zplprop(objset_t *os, zfs_prop_t prop, uint64_t *value);
312 extern int	zfs_set_version(const char *name, uint64_t newvers);
313 extern int	zfs_get_stats(objset_t *os, nvlist_t *nv);
314 extern void	zfs_znode_dmu_fini(znode_t *);
315 
316 extern void zfs_log_create(zilog_t *zilog, dmu_tx_t *tx, uint64_t txtype,
317     znode_t *dzp, znode_t *zp, char *name, vsecattr_t *, zfs_fuid_info_t *,
318     vattr_t *vap);
319 extern int zfs_log_create_txtype(zil_create_t, vsecattr_t *vsecp,
320     vattr_t *vap);
321 extern void zfs_log_remove(zilog_t *zilog, dmu_tx_t *tx, uint64_t txtype,
322     znode_t *dzp, char *name);
323 extern void zfs_log_link(zilog_t *zilog, dmu_tx_t *tx, uint64_t txtype,
324     znode_t *dzp, znode_t *zp, char *name);
325 extern void zfs_log_symlink(zilog_t *zilog, dmu_tx_t *tx, uint64_t txtype,
326     znode_t *dzp, znode_t *zp, char *name, char *link);
327 extern void zfs_log_rename(zilog_t *zilog, dmu_tx_t *tx, uint64_t txtype,
328     znode_t *sdzp, char *sname, znode_t *tdzp, char *dname, znode_t *szp);
329 extern void zfs_log_write(zilog_t *zilog, dmu_tx_t *tx, int txtype,
330     znode_t *zp, offset_t off, ssize_t len, int ioflag);
331 extern void zfs_log_truncate(zilog_t *zilog, dmu_tx_t *tx, int txtype,
332     znode_t *zp, uint64_t off, uint64_t len);
333 extern void zfs_log_setattr(zilog_t *zilog, dmu_tx_t *tx, int txtype,
334     znode_t *zp, vattr_t *vap, uint_t mask_applied, zfs_fuid_info_t *fuidp);
335 extern void zfs_log_acl(zilog_t *zilog, dmu_tx_t *tx, znode_t *zp,
336     vsecattr_t *vsecp, zfs_fuid_info_t *fuidp);
337 extern void zfs_xvattr_set(znode_t *zp, xvattr_t *xvap);
338 extern void zfs_upgrade(zfsvfs_t *zfsvfs, dmu_tx_t *tx);
339 
340 extern caddr_t zfs_map_page(page_t *, enum seg_rw);
341 extern void zfs_unmap_page(page_t *, caddr_t);
342 
343 extern zil_get_data_t zfs_get_data;
344 extern zil_replay_func_t *zfs_replay_vector[TX_MAX_TYPE];
345 extern int zfsfstype;
346 
347 #endif /* _KERNEL */
348 
349 extern int zfs_obj_to_path(objset_t *osp, uint64_t obj, char *buf, int len);
350 
351 #ifdef	__cplusplus
352 }
353 #endif
354 
355 #endif	/* _SYS_FS_ZFS_ZNODE_H */
356