1 /* 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)filedesc.h 8.1 (Berkeley) 6/2/93 34 * $FreeBSD: src/sys/sys/filedesc.h,v 1.19.2.5 2003/06/06 20:21:32 tegge Exp $ 35 * $DragonFly: src/sys/sys/filedesc.h,v 1.19 2006/05/26 02:26:26 dillon Exp $ 36 */ 37 38 #ifndef _SYS_FILEDESC_H_ 39 #define _SYS_FILEDESC_H_ 40 41 #ifndef _SYS_TYPES_H_ 42 #include <sys/types.h> 43 #endif 44 #ifndef _SYS_QUEUE_H_ 45 #include <sys/queue.h> 46 #endif 47 #ifndef _SYS_SPINLOCK_H_ 48 #include <sys/spinlock.h> 49 #endif 50 51 /* 52 * This structure is used for the management of descriptors. It may be 53 * shared by multiple processes. 54 * 55 * A process is initially started out with NDFILE descriptors stored within 56 * this structure, selected to be enough for typical applications based on 57 * the historical limit of 20 open files (and the usage of descriptors by 58 * shells) and the constraint of being one less than a power of 2. 59 * If these descriptors are exhausted, a larger descriptor table 60 * may be allocated, up to a process' resource limit; the internal arrays 61 * are then unused. Each time the file table runs out, it is doubled until 62 * the resource limit is reached. 63 */ 64 #define NDFILE 15 /* must be of the form 2^n - 1 */ 65 66 struct file; 67 struct klist; 68 struct namecache; 69 70 struct fdnode { 71 struct file *fp; 72 char fileflags; 73 char unused01; 74 char unused02; 75 char reserved; /* descriptor has been reserved */ 76 int allocated; /* subtree allocation count */ 77 }; 78 79 struct filedesc { 80 struct fdnode *fd_files; /* file structures for open files */ 81 struct vnode *fd_cdir; /* current directory (phaseout) */ 82 struct vnode *fd_rdir; /* root directory (phaseout) */ 83 struct vnode *fd_jdir; /* jail root directory (phaseout) */ 84 struct namecache *fd_ncdir; /* current directory */ 85 struct namecache *fd_nrdir; /* root directory */ 86 struct namecache *fd_njdir; /* jail directory */ 87 int fd_nfiles; /* number of open files allocated */ 88 int fd_lastfile; /* high-water mark of fd_files */ 89 int fd_freefile; /* approx. next free file */ 90 int fd_cmask; /* mask for file creation */ 91 int fd_refcnt; /* reference count */ 92 93 int fd_knlistsize; /* size of knlist */ 94 struct klist *fd_knlist; /* list of attached knotes */ 95 u_long fd_knhashmask; /* size of knhash */ 96 struct klist *fd_knhash; /* hash table for attached knotes */ 97 int fd_holdleaderscount; /* block fdfree() for shared close() */ 98 int fd_holdleaderswakeup; /* fdfree() needs wakeup */ 99 struct spinlock fd_spin; 100 struct fdnode fd_builtin_files[NDFILE]; 101 }; 102 103 /* 104 * Structure to keep track of (process leader, struct fildedesc) tuples. 105 * Each process has a pointer to such a structure when detailed tracking 106 * is needed. e.g. when rfork(RFPROC | RFMEM) causes a file descriptor 107 * table to be shared by processes having different "p_leader" pointers 108 * and thus distinct POSIX style locks. 109 */ 110 struct filedesc_to_leader { 111 int fdl_refcount; /* references from struct proc */ 112 int fdl_holdcount; /* temporary hold during closef */ 113 int fdl_wakeup; /* fdfree() waits on closef() */ 114 struct proc *fdl_leader; /* owner of POSIX locks */ 115 /* Circular list */ 116 struct filedesc_to_leader *fdl_prev; 117 struct filedesc_to_leader *fdl_next; 118 }; 119 120 /* 121 * Per-process open flags. 122 */ 123 #define UF_EXCLOSE 0x01 /* auto-close on exec */ 124 125 /* 126 * This structure that holds the information needed to send a SIGIO or 127 * a SIGURG signal to a process or process group when new data arrives 128 * on a device or socket. The structure is placed on an SLIST belonging 129 * to the proc or pgrp so that the entire list may be revoked when the 130 * process exits or the process group disappears. 131 */ 132 struct sigio { 133 union { 134 struct proc *siu_proc; /* process to receive SIGIO/SIGURG */ 135 struct pgrp *siu_pgrp; /* process group to receive ... */ 136 } sio_u; 137 SLIST_ENTRY(sigio) sio_pgsigio; /* sigio's for process or group */ 138 struct sigio **sio_myref; /* location of the pointer that holds 139 * the reference to this structure */ 140 struct ucred *sio_ucred; /* current credentials */ 141 uid_t sio_ruid; /* real user id */ 142 pid_t sio_pgid; /* pgid for signals */ 143 }; 144 #define sio_proc sio_u.siu_proc 145 #define sio_pgrp sio_u.siu_pgrp 146 147 SLIST_HEAD(sigiolst, sigio); 148 149 #ifdef _KERNEL 150 151 struct thread; 152 struct proc; 153 154 /* 155 * Kernel global variables and routines. 156 */ 157 int dupfdopen (struct proc *, int, int, int, int); 158 int fdalloc (struct proc *p, int want, int *result); 159 int fdavail (struct proc *p, int n); 160 int falloc (struct proc *p, struct file **resultfp, int *resultfd); 161 void fsetfd (struct proc *p, struct file *fp, int fd); 162 int fgetfdflags(struct filedesc *fdp, int fd, int *flagsp); 163 int fsetfdflags(struct filedesc *fdp, int fd, int add_flags); 164 int fclrfdflags(struct filedesc *fdp, int fd, int rem_flags); 165 void fsetcred (struct file *fp, struct ucred *cr); 166 void fdinit_bootstrap(struct proc *p0, struct filedesc *fdp0, int cmask); 167 struct filedesc *fdinit (struct proc *p); 168 struct filedesc *fdshare (struct proc *p); 169 struct filedesc *fdcopy (struct proc *p); 170 void fdfree (struct proc *p); 171 int closef (struct file *fp, struct thread *td); 172 void fdcloseexec (struct proc *p); 173 int fdcheckstd (struct proc *p); 174 struct file *holdfp (struct filedesc *fdp, int fd, int flag); 175 int holdsock (struct filedesc *fdp, int fdes, struct file **fpp); 176 int holdvnode (struct filedesc *fdp, int fd, struct file **fpp); 177 int fdissequential (struct file *); 178 void fdsequential (struct file *, int); 179 pid_t fgetown (struct sigio *); 180 int fsetown (pid_t, struct sigio **); 181 void funsetown (struct sigio *); 182 void funsetownlst (struct sigiolst *); 183 void setugidsafety (struct proc *p); 184 void allfiles_scan_exclusive(int (*callback)(struct file *, void *), void *data); 185 186 struct filedesc_to_leader * 187 filedesc_to_leader_alloc(struct filedesc_to_leader *old, 188 struct proc *leader); 189 190 #endif 191 192 #endif 193