Annotation of sys/sys/vnode.h, Revision 1.1
1.1 ! nbrk 1: /* $OpenBSD: vnode.h,v 1.88 2007/06/14 20:36:34 otto Exp $ */
! 2: /* $NetBSD: vnode.h,v 1.38 1996/02/29 20:59:05 cgd Exp $ */
! 3:
! 4: /*
! 5: * Copyright (c) 1989, 1993
! 6: * The Regents of the University of California. All rights reserved.
! 7: *
! 8: * Redistribution and use in source and binary forms, with or without
! 9: * modification, are permitted provided that the following conditions
! 10: * are met:
! 11: * 1. Redistributions of source code must retain the above copyright
! 12: * notice, this list of conditions and the following disclaimer.
! 13: * 2. Redistributions in binary form must reproduce the above copyright
! 14: * notice, this list of conditions and the following disclaimer in the
! 15: * documentation and/or other materials provided with the distribution.
! 16: * 3. Neither the name of the University nor the names of its contributors
! 17: * may be used to endorse or promote products derived from this software
! 18: * without specific prior written permission.
! 19: *
! 20: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
! 21: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
! 22: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
! 23: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
! 24: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
! 25: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
! 26: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
! 27: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
! 28: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
! 29: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
! 30: * SUCH DAMAGE.
! 31: *
! 32: * @(#)vnode.h 8.11 (Berkeley) 11/21/94
! 33: */
! 34:
! 35: #include <sys/types.h>
! 36: #include <sys/queue.h>
! 37: #include <sys/lock.h>
! 38: #include <sys/selinfo.h>
! 39:
! 40: #include <uvm/uvm.h>
! 41: #include <uvm/uvm_vnode.h>
! 42:
! 43: /*
! 44: * The vnode is the focus of all file activity in UNIX. There is a
! 45: * unique vnode allocated for each active file, each current directory,
! 46: * each mounted-on file, text file, and the root.
! 47: */
! 48:
! 49: /*
! 50: * Vnode types. VNON means no type.
! 51: */
! 52: enum vtype { VNON, VREG, VDIR, VBLK, VCHR, VLNK, VSOCK, VFIFO, VBAD };
! 53:
! 54: #define VTYPE_NAMES \
! 55: "VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD"
! 56:
! 57: /*
! 58: * Vnode tag types.
! 59: * These are for the benefit of external programs only (e.g., pstat)
! 60: * and should NEVER be inspected by the kernel.
! 61: *
! 62: * Note that v_tag is actually used to tell MFS from FFS, and EXT2FS from
! 63: * the rest, so don't believe the above comment!
! 64: */
! 65: enum vtagtype {
! 66: VT_NON, VT_UFS, VT_NFS, VT_MFS, VT_MSDOSFS,
! 67: VT_PORTAL, VT_PROCFS, VT_AFS, VT_ISOFS, VT_ADOSFS,
! 68: VT_EXT2FS, VT_VFS, VT_XFS, VT_NTFS, VT_UDF
! 69: };
! 70:
! 71: #define VTAG_NAMES \
! 72: "NON", "UFS", "NFS", "MFS", "MSDOSFS", \
! 73: "PORTAL", "PROCFS", "AFS", "ISOFS", "ADOSFS", \
! 74: "EXT2FS", "VFS", "XFS", "NTFS", "UDF"
! 75:
! 76: /*
! 77: * Each underlying filesystem allocates its own private area and hangs
! 78: * it from v_data. If non-null, this area is freed in getnewvnode().
! 79: */
! 80: LIST_HEAD(buflists, buf);
! 81:
! 82: struct vnode {
! 83: struct uvm_vnode v_uvm; /* uvm data */
! 84: int (**v_op)(void *); /* vnode operations vector */
! 85: enum vtype v_type; /* vnode type */
! 86: u_int v_flag; /* vnode flags (see below) */
! 87: u_int v_usecount; /* reference count of users */
! 88: /* reference count of writers */
! 89: u_int v_writecount;
! 90: /* Flags that can be read/written in interrupts */
! 91: u_int v_bioflag;
! 92: u_int v_holdcnt; /* buffer references */
! 93: u_int v_id; /* capability identifier */
! 94: struct mount *v_mount; /* ptr to vfs we are in */
! 95: TAILQ_ENTRY(vnode) v_freelist; /* vnode freelist */
! 96: LIST_ENTRY(vnode) v_mntvnodes; /* vnodes for mount point */
! 97: struct buflists v_cleanblkhd; /* clean blocklist head */
! 98: struct buflists v_dirtyblkhd; /* dirty blocklist head */
! 99: u_int v_numoutput; /* num of writes in progress */
! 100: LIST_ENTRY(vnode) v_synclist; /* vnode with dirty buffers */
! 101: union {
! 102: struct mount *vu_mountedhere;/* ptr to mounted vfs (VDIR) */
! 103: struct socket *vu_socket; /* unix ipc (VSOCK) */
! 104: struct specinfo *vu_specinfo; /* device (VCHR, VBLK) */
! 105: struct fifoinfo *vu_fifoinfo; /* fifo (VFIFO) */
! 106: } v_un;
! 107:
! 108: enum vtagtype v_tag; /* type of underlying data */
! 109: void *v_data; /* private data for fs */
! 110: struct selinfo v_selectinfo; /* identity of poller(s) */
! 111: };
! 112: #define v_mountedhere v_un.vu_mountedhere
! 113: #define v_socket v_un.vu_socket
! 114: #define v_specinfo v_un.vu_specinfo
! 115: #define v_fifoinfo v_un.vu_fifoinfo
! 116:
! 117: /*
! 118: * Vnode flags.
! 119: */
! 120: #define VROOT 0x0001 /* root of its file system */
! 121: #define VTEXT 0x0002 /* vnode is a pure text prototype */
! 122: #define VSYSTEM 0x0004 /* vnode being used by kernel */
! 123: #define VISTTY 0x0008 /* vnode represents a tty */
! 124: #define VXLOCK 0x0100 /* vnode is locked to change underlying type */
! 125: #define VXWANT 0x0200 /* process is waiting for vnode */
! 126: #define VCLONED 0x0400 /* vnode was cloned */
! 127: #define VALIASED 0x0800 /* vnode has an alias */
! 128: #define VLOCKSWORK 0x4000 /* FS supports locking discipline */
! 129: #define VBITS "\010\001ROOT\002TEXT\003SYSTEM\004ISTTY\010XLOCK" \
! 130: "\011XWANT\013ALIASED\016LOCKSWORK"
! 131:
! 132: /*
! 133: * (v_bioflag) Flags that may be manipulated by interrupt handlers
! 134: */
! 135: #define VBIOWAIT 0x0001 /* waiting for output to complete */
! 136: #define VBIOONSYNCLIST 0x0002 /* Vnode is on syncer worklist */
! 137: #define VBIOONFREELIST 0x0004 /* Vnode is on a free list */
! 138:
! 139: /*
! 140: * Vnode attributes. A field value of VNOVAL represents a field whose value
! 141: * is unavailable (getattr) or which is not to be changed (setattr).
! 142: */
! 143: struct vattr {
! 144: enum vtype va_type; /* vnode type (for create) */
! 145: mode_t va_mode; /* files access mode and type */
! 146: nlink_t va_nlink; /* number of references to file */
! 147: uid_t va_uid; /* owner user id */
! 148: gid_t va_gid; /* owner group id */
! 149: long va_fsid; /* file system id (dev for now) */
! 150: long va_fileid; /* file id */
! 151: u_quad_t va_size; /* file size in bytes */
! 152: long va_blocksize; /* blocksize preferred for i/o */
! 153: struct timespec va_atime; /* time of last access */
! 154: struct timespec va_mtime; /* time of last modification */
! 155: struct timespec va_ctime; /* time file changed */
! 156: u_long va_gen; /* generation number of file */
! 157: u_long va_flags; /* flags defined for file */
! 158: dev_t va_rdev; /* device the special file represents */
! 159: u_quad_t va_bytes; /* bytes of disk space held by file */
! 160: u_quad_t va_filerev; /* file modification number */
! 161: u_int va_vaflags; /* operations flags, see below */
! 162: long va_spare; /* remain quad aligned */
! 163: };
! 164:
! 165: /*
! 166: * Flags for va_cflags.
! 167: */
! 168: #define VA_UTIMES_NULL 0x01 /* utimes argument was NULL */
! 169: #define VA_EXCLUSIVE 0x02 /* exclusive create request */
! 170: /*
! 171: * Flags for ioflag.
! 172: */
! 173: #define IO_UNIT 0x01 /* do I/O as atomic unit */
! 174: #define IO_APPEND 0x02 /* append write to end */
! 175: #define IO_SYNC 0x04 /* do I/O synchronously */
! 176: #define IO_NODELOCKED 0x08 /* underlying node already locked */
! 177: #define IO_NDELAY 0x10 /* FNDELAY flag set in file table */
! 178: #define IO_NOLIMIT 0x20 /* don't enforce limits on i/o */
! 179:
! 180: /*
! 181: * Modes. Some values same as Ixxx entries from inode.h for now.
! 182: */
! 183: #define VSUID 04000 /* set user id on execution */
! 184: #define VSGID 02000 /* set group id on execution */
! 185: #define VSVTX 01000 /* save swapped text even after use */
! 186: #define VREAD 00400 /* read, write, execute permissions */
! 187: #define VWRITE 00200
! 188: #define VEXEC 00100
! 189:
! 190: /*
! 191: * Token indicating no attribute value yet assigned.
! 192: */
! 193: #define VNOVAL (-1)
! 194:
! 195: /*
! 196: * Structure returned by the KERN_VNODE sysctl
! 197: */
! 198: struct e_vnode {
! 199: struct vnode *vptr;
! 200: struct vnode vnode;
! 201: };
! 202:
! 203: #ifdef _KERNEL
! 204: /*
! 205: * Convert between vnode types and inode formats (since POSIX.1
! 206: * defines mode word of stat structure in terms of inode formats).
! 207: */
! 208: extern enum vtype iftovt_tab[];
! 209: extern int vttoif_tab[];
! 210: #define IFTOVT(mode) (iftovt_tab[((mode) & S_IFMT) >> 12])
! 211: #define VTTOIF(indx) (vttoif_tab[(int)(indx)])
! 212: #define MAKEIMODE(indx, mode) (int)(VTTOIF(indx) | (mode))
! 213:
! 214: /*
! 215: * Flags to various vnode functions.
! 216: */
! 217: #define SKIPSYSTEM 0x0001 /* vflush: skip vnodes marked VSYSTEM */
! 218: #define FORCECLOSE 0x0002 /* vflush: force file closeure */
! 219: #define WRITECLOSE 0x0004 /* vflush: only close writeable files */
! 220: #define DOCLOSE 0x0008 /* vclean: close active files */
! 221: #define V_SAVE 0x0001 /* vinvalbuf: sync file first */
! 222: #define V_SAVEMETA 0x0002 /* vinvalbuf: leave indirect blocks */
! 223:
! 224: #define REVOKEALL 0x0001 /* vop_revoke: revoke all aliases */
! 225:
! 226:
! 227: TAILQ_HEAD(freelst, vnode);
! 228: extern struct freelst vnode_hold_list; /* free vnodes referencing buffers */
! 229: extern struct freelst vnode_free_list; /* vnode free list */
! 230:
! 231: #define VATTR_NULL(vap) vattr_null(vap)
! 232: #define VREF(vp) vref(vp) /* increase reference */
! 233: #define NULLVP ((struct vnode *)NULL)
! 234: #define VN_KNOTE(vp, b) \
! 235: KNOTE(&vp->v_selectinfo.si_note, (b))
! 236:
! 237: /*
! 238: * Global vnode data.
! 239: */
! 240: extern struct vnode *rootvnode; /* root (i.e. "/") vnode */
! 241: extern int desiredvnodes; /* XXX number of vnodes desired */
! 242: extern int maxvnodes; /* XXX number of vnodes to allocate */
! 243: extern time_t syncdelay; /* time to delay syncing vnodes */
! 244: extern int rushjob; /* # of slots syncer should run ASAP */
! 245: #endif /* _KERNEL */
! 246:
! 247:
! 248: /*
! 249: * Mods for exensibility.
! 250: */
! 251:
! 252: /*
! 253: * Flags for vdesc_flags:
! 254: */
! 255: #define VDESC_MAX_VPS 16
! 256: /* Low order 16 flag bits are reserved for willrele flags for vp arguments. */
! 257: #define VDESC_VP0_WILLRELE 0x00000001
! 258: #define VDESC_VP1_WILLRELE 0x00000002
! 259: #define VDESC_VP2_WILLRELE 0x00000004
! 260: #define VDESC_VP3_WILLRELE 0x00000008
! 261: #define VDESC_VP0_WILLUNLOCK 0x00000100
! 262: #define VDESC_VP1_WILLUNLOCK 0x00000200
! 263: #define VDESC_VP2_WILLUNLOCK 0x00000400
! 264: #define VDESC_VP3_WILLUNLOCK 0x00000800
! 265: #define VDESC_VP0_WILLPUT 0x00000101
! 266: #define VDESC_VP1_WILLPUT 0x00000202
! 267: #define VDESC_VP2_WILLPUT 0x00000404
! 268: #define VDESC_VP3_WILLPUT 0x00000808
! 269: #define VDESC_NOMAP_VPP 0x00010000
! 270: #define VDESC_VPP_WILLRELE 0x00020000
! 271:
! 272: /*
! 273: * VDESC_NO_OFFSET is used to identify the end of the offset list
! 274: * and in places where no such field exists.
! 275: */
! 276: #define VDESC_NO_OFFSET -1
! 277:
! 278: /*
! 279: * This structure describes the vnode operation taking place.
! 280: */
! 281: struct vnodeop_desc {
! 282: int vdesc_offset; /* offset in vector--first for speed */
! 283: char *vdesc_name; /* a readable name for debugging */
! 284: int vdesc_flags; /* VDESC_* flags */
! 285:
! 286: /*
! 287: * These ops are used by bypass routines to map and locate arguments.
! 288: * Creds and procs are not needed in bypass routines, but sometimes
! 289: * they are useful to (for example) transport layers.
! 290: * Nameidata is useful because it has a cred in it.
! 291: */
! 292: int *vdesc_vp_offsets; /* list ended by VDESC_NO_OFFSET */
! 293: int vdesc_vpp_offset; /* return vpp location */
! 294: int vdesc_cred_offset; /* cred location, if any */
! 295: int vdesc_proc_offset; /* proc location, if any */
! 296: int vdesc_componentname_offset; /* if any */
! 297: /*
! 298: * Finally, we've got a list of private data (about each operation)
! 299: * for each transport layer. (Support to manage this list is not
! 300: * yet part of BSD.)
! 301: */
! 302: caddr_t *vdesc_transports;
! 303: };
! 304:
! 305: #ifdef _KERNEL
! 306: /*
! 307: * A list of all the operation descs.
! 308: */
! 309: extern struct vnodeop_desc *vnodeop_descs[];
! 310:
! 311:
! 312: /*
! 313: * This macro is very helpful in defining those offsets in the vdesc struct.
! 314: *
! 315: * This is stolen from X11R4. I ingored all the fancy stuff for
! 316: * Crays, so if you decide to port this to such a serious machine,
! 317: * you might want to consult Intrisics.h's XtOffset{,Of,To}.
! 318: */
! 319: #define VOPARG_OFFSET(p_type,field) \
! 320: ((int) (((char *) (&(((p_type)NULL)->field))) - ((char *) NULL)))
! 321: #define VOPARG_OFFSETOF(s_type,field) \
! 322: VOPARG_OFFSET(s_type*,field)
! 323: #define VOPARG_OFFSETTO(S_TYPE,S_OFFSET,STRUCT_P) \
! 324: ((S_TYPE)(((char *)(STRUCT_P))+(S_OFFSET)))
! 325:
! 326:
! 327: /*
! 328: * This structure is used to configure the new vnodeops vector.
! 329: */
! 330: struct vnodeopv_entry_desc {
! 331: struct vnodeop_desc *opve_op; /* which operation this is */
! 332: int (*opve_impl)(void *); /* code implementing this operation */
! 333: };
! 334: struct vnodeopv_desc {
! 335: /* ptr to the ptr to the vector where op should go */
! 336: int (***opv_desc_vector_p)(void *);
! 337: struct vnodeopv_entry_desc *opv_desc_ops; /* null terminated list */
! 338: };
! 339:
! 340: /*
! 341: * A default routine which just returns an error.
! 342: */
! 343: int vn_default_error(void *);
! 344:
! 345: /*
! 346: * A generic structure.
! 347: * This can be used by bypass routines to identify generic arguments.
! 348: */
! 349: struct vop_generic_args {
! 350: struct vnodeop_desc *a_desc;
! 351: /* other random data follows, presumably */
! 352: };
! 353:
! 354: /*
! 355: * VOCALL calls an op given an ops vector. We break it out because BSD's
! 356: * vclean changes the ops vector and then wants to call ops with the old
! 357: * vector.
! 358: */
! 359: #define VOCALL(OPSV,OFF,AP) (( *((OPSV)[(OFF)])) (AP))
! 360:
! 361: /*
! 362: * This call works for vnodes in the kernel.
! 363: */
! 364: #define VCALL(VP,OFF,AP) VOCALL((VP)->v_op,(OFF),(AP))
! 365: #define VDESC(OP) (& __CONCAT(OP,_desc))
! 366: #define VOFFSET(OP) (VDESC(OP)->vdesc_offset)
! 367:
! 368: /*
! 369: * Finally, include the default set of vnode operations.
! 370: */
! 371: #include <sys/vnode_if.h>
! 372:
! 373: /*
! 374: * Public vnode manipulation functions.
! 375: */
! 376: struct file;
! 377: struct filedesc;
! 378: struct mount;
! 379: struct nameidata;
! 380: struct proc;
! 381: struct stat;
! 382: struct ucred;
! 383: struct uio;
! 384: struct vattr;
! 385: struct vnode;
! 386:
! 387: /* vfs_subr */
! 388: int bdevvp(dev_t, struct vnode **);
! 389: int cdevvp(dev_t, struct vnode **);
! 390: struct vnode *checkalias(struct vnode *, dev_t, struct mount *);
! 391: int getnewvnode(enum vtagtype, struct mount *, int (**vops)(void *),
! 392: struct vnode **);
! 393: int vaccess(mode_t, uid_t, gid_t, mode_t, struct ucred *);
! 394: void vattr_null(struct vattr *);
! 395: void vdevgone(int, int, int, enum vtype);
! 396: int vcount(struct vnode *);
! 397: int vfinddev(dev_t, enum vtype, struct vnode **);
! 398: void vflushbuf(struct vnode *, int);
! 399: int vflush(struct mount *, struct vnode *, int);
! 400: int vget(struct vnode *, int, struct proc *);
! 401: void vgone(struct vnode *);
! 402: void vgonel(struct vnode *, struct proc *);
! 403: int vinvalbuf(struct vnode *, int, struct ucred *, struct proc *,
! 404: int, int);
! 405: void vntblinit(void);
! 406: int vwaitforio(struct vnode *, int, char *, int);
! 407: void vwakeup(struct vnode *);
! 408: void vput(struct vnode *);
! 409: int vrecycle(struct vnode *, struct proc *);
! 410: void vrele(struct vnode *);
! 411: void vref(struct vnode *);
! 412: void vprint(char *, struct vnode *);
! 413:
! 414: /* vfs_getcwd.c */
! 415: int vfs_getcwd_scandir(struct vnode **, struct vnode **, char **, char *,
! 416: struct proc *);
! 417: int vfs_getcwd_common(struct vnode *, struct vnode *, char **, char *, int,
! 418: int, struct proc *);
! 419: int vfs_getcwd_getcache(struct vnode **, struct vnode **, char **, char *);
! 420:
! 421: /* vfs_default.c */
! 422: int vop_generic_abortop(void *);
! 423: int vop_generic_bwrite(void *);
! 424: int vop_generic_islocked(void *);
! 425: int vop_generic_lock(void *);
! 426: int vop_generic_unlock(void *);
! 427: int vop_generic_revoke(void *);
! 428: int vop_generic_kqfilter(void *);
! 429:
! 430: /* vfs_vnops.c */
! 431: int vn_isunder(struct vnode *, struct vnode *, struct proc *);
! 432: int vn_close(struct vnode *, int, struct ucred *, struct proc *);
! 433: int vn_open(struct nameidata *, int, int);
! 434: int vn_rdwr(enum uio_rw, struct vnode *, caddr_t, int, off_t,
! 435: enum uio_seg, int, struct ucred *, size_t *, struct proc *);
! 436: int vn_stat(struct vnode *, struct stat *, struct proc *);
! 437: int vn_statfile(struct file *, struct stat *, struct proc *);
! 438: int vn_lock(struct vnode *, int, struct proc *);
! 439: int vn_writechk(struct vnode *);
! 440: int vn_ioctl(struct file *, u_long, caddr_t, struct proc *);
! 441: void vn_marktext(struct vnode *);
! 442:
! 443: /* vfs_sync.c */
! 444: void sched_sync(struct proc *);
! 445: void vn_initialize_syncerd(void);
! 446: void vn_syncer_add_to_worklist(struct vnode *, int);
! 447:
! 448: /* misc */
! 449: int vn_isdisk(struct vnode *, int *);
! 450: int softdep_fsync(struct vnode *);
! 451: int getvnode(struct filedesc *, int, struct file **);
! 452:
! 453: #endif /* _KERNEL */
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