xref: /onnv-gate/usr/src/uts/common/sys/fs/tmpnode.h (revision 9694:78fafb281255)
10Sstevel@tonic-gate /*
20Sstevel@tonic-gate  * CDDL HEADER START
30Sstevel@tonic-gate  *
40Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*9694SScott.Rotondo@Sun.COM  * Common Development and Distribution License (the "License").
6*9694SScott.Rotondo@Sun.COM  * You may not use this file except in compliance with the License.
70Sstevel@tonic-gate  *
80Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
90Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
100Sstevel@tonic-gate  * See the License for the specific language governing permissions
110Sstevel@tonic-gate  * and limitations under the License.
120Sstevel@tonic-gate  *
130Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
140Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
150Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
160Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
170Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
180Sstevel@tonic-gate  *
190Sstevel@tonic-gate  * CDDL HEADER END
200Sstevel@tonic-gate  */
210Sstevel@tonic-gate /*
22*9694SScott.Rotondo@Sun.COM  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
230Sstevel@tonic-gate  * Use is subject to license terms.
240Sstevel@tonic-gate  */
250Sstevel@tonic-gate 
260Sstevel@tonic-gate #ifndef _SYS_FS_TMPNODE_H
270Sstevel@tonic-gate #define	_SYS_FS_TMPNODE_H
280Sstevel@tonic-gate 
290Sstevel@tonic-gate #include <sys/t_lock.h>
300Sstevel@tonic-gate #include <vm/seg.h>
310Sstevel@tonic-gate #include <vm/seg_vn.h>
32*9694SScott.Rotondo@Sun.COM #include <sys/vfs_opreg.h>
330Sstevel@tonic-gate 
340Sstevel@tonic-gate #ifdef	__cplusplus
350Sstevel@tonic-gate extern "C" {
360Sstevel@tonic-gate #endif
370Sstevel@tonic-gate 
380Sstevel@tonic-gate /*
390Sstevel@tonic-gate  * tmpnode is the file system dependent node for tmpfs.
400Sstevel@tonic-gate  *
410Sstevel@tonic-gate  *	tn_rwlock protects access of the directory list at tn_dir
420Sstevel@tonic-gate  *	as well as syncronizing read and writes to the tmpnode
430Sstevel@tonic-gate  *
440Sstevel@tonic-gate  *	tn_contents protects growing, shrinking, reading and writing
450Sstevel@tonic-gate  *	the file along with tn_rwlock (see below).
460Sstevel@tonic-gate  *
470Sstevel@tonic-gate  *	tn_tlock protects updates to tn_mode and tn_nlink
480Sstevel@tonic-gate  *
490Sstevel@tonic-gate  *	tm_contents in the tmount filesystem data structure protects
500Sstevel@tonic-gate  *	tn_forw and tn_back which are used to maintain a linked
510Sstevel@tonic-gate  *	list of all tmpfs files associated with that file system
520Sstevel@tonic-gate  *
530Sstevel@tonic-gate  *	The anon array represents the secondary store for tmpfs.
540Sstevel@tonic-gate  * 	To grow or shrink the file or fill in holes requires
550Sstevel@tonic-gate  *	manipulation of the anon array. These operations are protected
560Sstevel@tonic-gate  *	by a combination of tn_rwlock and tn_contents. Growing or shrinking
570Sstevel@tonic-gate  * 	the array requires the write lock on tn_rwlock and tn_contents.
580Sstevel@tonic-gate  *	Filling in a slot in the array requires the write lock on tn_contents.
590Sstevel@tonic-gate  *	Reading the array requires the read lock on tn_contents.
600Sstevel@tonic-gate  *
610Sstevel@tonic-gate  *	The ordering of the locking is:
620Sstevel@tonic-gate  *	tn_rwlock -> tn_contents -> page locks on pages in file
630Sstevel@tonic-gate  *
640Sstevel@tonic-gate  *	tn_tlock doesn't require any tmpnode locks
650Sstevel@tonic-gate  */
660Sstevel@tonic-gate 
670Sstevel@tonic-gate struct tmpnode {
680Sstevel@tonic-gate 	struct tmpnode	*tn_back;		/* linked list of tmpnodes */
690Sstevel@tonic-gate 	struct tmpnode	*tn_forw;		/* linked list of tmpnodes */
700Sstevel@tonic-gate 	union {
710Sstevel@tonic-gate 		struct {
720Sstevel@tonic-gate 			struct tdirent	*un_dirlist; /* dirent list */
730Sstevel@tonic-gate 			uint_t	un_dirents;	/* number of dirents */
740Sstevel@tonic-gate 		} un_dirstruct;
750Sstevel@tonic-gate 		char 		*un_symlink;	/* pointer to symlink */
760Sstevel@tonic-gate 		struct {
770Sstevel@tonic-gate 			struct anon_hdr	*un_anon; /* anon backing for file */
780Sstevel@tonic-gate 			pgcnt_t	un_size;	/* size repres. by array */
790Sstevel@tonic-gate 		} un_anonstruct;
800Sstevel@tonic-gate 	} un_tmpnode;
810Sstevel@tonic-gate 	struct vnode 	*tn_vnode;		/* vnode for this tmpnode */
820Sstevel@tonic-gate 	int 		tn_gen;			/* pseudo gen number for tfid */
830Sstevel@tonic-gate 	struct vattr	tn_attr;		/* attributes */
840Sstevel@tonic-gate 	krwlock_t	tn_contents;		/* vm side -serialize mods */
850Sstevel@tonic-gate 	krwlock_t	tn_rwlock;		/* rw,trunc size - serialize */
860Sstevel@tonic-gate 						/* mods and directory updates */
870Sstevel@tonic-gate 	kmutex_t	tn_tlock;		/* time, flag, and nlink lock */
880Sstevel@tonic-gate 	struct tmpnode *tn_xattrdp;		/* ext. attribute directory */
890Sstevel@tonic-gate 	uint_t		tn_flags;		/* tmpnode specific flags */
900Sstevel@tonic-gate };
910Sstevel@tonic-gate 
920Sstevel@tonic-gate #define	tn_dir		un_tmpnode.un_dirstruct.un_dirlist
930Sstevel@tonic-gate #define	tn_dirents	un_tmpnode.un_dirstruct.un_dirents
940Sstevel@tonic-gate #define	tn_symlink	un_tmpnode.un_symlink
950Sstevel@tonic-gate #define	tn_anon		un_tmpnode.un_anonstruct.un_anon
960Sstevel@tonic-gate #define	tn_asize	un_tmpnode.un_anonstruct.un_size
970Sstevel@tonic-gate 
980Sstevel@tonic-gate /*
990Sstevel@tonic-gate  * tmnode flag values.
1000Sstevel@tonic-gate  */
1010Sstevel@tonic-gate #define	ISXATTR		0x1
1020Sstevel@tonic-gate 
1030Sstevel@tonic-gate /*
1040Sstevel@tonic-gate  * Attributes
1050Sstevel@tonic-gate  */
1060Sstevel@tonic-gate #define	tn_mask		tn_attr.va_mask
1070Sstevel@tonic-gate #define	tn_type		tn_attr.va_type
1080Sstevel@tonic-gate #define	tn_mode		tn_attr.va_mode
1090Sstevel@tonic-gate #define	tn_uid		tn_attr.va_uid
1100Sstevel@tonic-gate #define	tn_gid		tn_attr.va_gid
1110Sstevel@tonic-gate #define	tn_fsid		tn_attr.va_fsid
1120Sstevel@tonic-gate #define	tn_nodeid	tn_attr.va_nodeid
1130Sstevel@tonic-gate #define	tn_nlink	tn_attr.va_nlink
1140Sstevel@tonic-gate #define	tn_size		tn_attr.va_size
1150Sstevel@tonic-gate #define	tn_atime	tn_attr.va_atime
1160Sstevel@tonic-gate #define	tn_mtime	tn_attr.va_mtime
1170Sstevel@tonic-gate #define	tn_ctime	tn_attr.va_ctime
1180Sstevel@tonic-gate #define	tn_rdev		tn_attr.va_rdev
1190Sstevel@tonic-gate #define	tn_blksize	tn_attr.va_blksize
1200Sstevel@tonic-gate #define	tn_nblocks	tn_attr.va_nblocks
1210Sstevel@tonic-gate #define	tn_seq		tn_attr.va_seq
1220Sstevel@tonic-gate 
1230Sstevel@tonic-gate /*
1240Sstevel@tonic-gate  * tmpfs directories are made up of a linked list of tdirent structures
1250Sstevel@tonic-gate  * hanging off directory tmpnodes.  File names are not fixed length,
1260Sstevel@tonic-gate  * but are null terminated.
1270Sstevel@tonic-gate  */
1280Sstevel@tonic-gate struct tdirent {
1290Sstevel@tonic-gate 	struct tmpnode	*td_tmpnode;		/* tnode for this file */
1300Sstevel@tonic-gate 	struct tdirent	*td_next;		/* next directory entry */
1310Sstevel@tonic-gate 	struct tdirent	*td_prev;		/* prev directory entry */
1320Sstevel@tonic-gate 	uint_t		td_offset;		/* "offset" of dir entry */
1330Sstevel@tonic-gate 	uint_t		td_hash;		/* a hash of td_name */
1340Sstevel@tonic-gate 	struct tdirent	*td_link;		/* linked via the hash table */
1350Sstevel@tonic-gate 	struct tmpnode	*td_parent;		/* parent, dir we are in */
1360Sstevel@tonic-gate 	char		*td_name;		/* must be null terminated */
1370Sstevel@tonic-gate 						/* max length is MAXNAMELEN */
1380Sstevel@tonic-gate };
1390Sstevel@tonic-gate 
1400Sstevel@tonic-gate /*
1410Sstevel@tonic-gate  * tfid overlays the fid structure (for VFS_VGET)
1420Sstevel@tonic-gate  */
1430Sstevel@tonic-gate struct tfid {
1440Sstevel@tonic-gate 	uint16_t tfid_len;
1450Sstevel@tonic-gate 	ino32_t	tfid_ino;
1460Sstevel@tonic-gate 	int32_t	tfid_gen;
1470Sstevel@tonic-gate };
1480Sstevel@tonic-gate 
1490Sstevel@tonic-gate #define	ESAME	(-1)		/* trying to rename linked files (special) */
1500Sstevel@tonic-gate 
1510Sstevel@tonic-gate extern struct vnodeops *tmp_vnodeops;
1520Sstevel@tonic-gate extern const struct fs_operation_def tmp_vnodeops_template[];
1530Sstevel@tonic-gate 
1540Sstevel@tonic-gate #ifdef	__cplusplus
1550Sstevel@tonic-gate }
1560Sstevel@tonic-gate #endif
1570Sstevel@tonic-gate 
1580Sstevel@tonic-gate #endif	/* _SYS_FS_TMPNODE_H */
159