1200442Sjh/*- 2200442Sjh * Copyright (c) 1990, 1993 3200442Sjh * The Regents of the University of California. All rights reserved. 4263227Sjmmv * 5200442Sjh * Redistribution and use in source and binary forms, with or without 6263227Sjmmv * 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 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)filedesc.h 8.1 (Berkeley) 6/2/93 30 * $FreeBSD: stable/10/sys/sys/filedesc.h 321020 2017-07-15 17:25:40Z dchagin $ 31 */ 32 33#ifndef _SYS_FILEDESC_H_ 34#define _SYS_FILEDESC_H_ 35 36#include <sys/caprights.h> 37#include <sys/queue.h> 38#include <sys/event.h> 39#include <sys/lock.h> 40#include <sys/priority.h> 41#include <sys/seq.h> 42#include <sys/sx.h> 43 44#include <machine/_limits.h> 45 46struct filecaps { 47 cap_rights_t fc_rights; /* per-descriptor capability rights */ 48 u_long *fc_ioctls; /* per-descriptor allowed ioctls */ 49 int16_t fc_nioctls; /* fc_ioctls array size */ 50 uint32_t fc_fcntls; /* per-descriptor allowed fcntls */ 51}; 52 53struct filedescent { 54 struct file *fde_file; /* file structure for open file */ 55 struct filecaps fde_caps; /* per-descriptor rights */ 56 uint8_t fde_flags; /* per-process open file flags */ 57 seq_t fde_seq; /* keep file and caps in sync */ 58}; 59#define fde_rights fde_caps.fc_rights 60#define fde_fcntls fde_caps.fc_fcntls 61#define fde_ioctls fde_caps.fc_ioctls 62#define fde_nioctls fde_caps.fc_nioctls 63#define fde_change_size (offsetof(struct filedescent, fde_seq)) 64 65/* 66 * This structure is used for the management of descriptors. It may be 67 * shared by multiple processes. 68 */ 69#define NDSLOTTYPE u_long 70 71struct filedesc { 72 struct filedescent *fd_ofiles; /* open files */ 73 struct vnode *fd_cdir; /* current directory */ 74 struct vnode *fd_rdir; /* root directory */ 75 struct vnode *fd_jdir; /* jail root directory */ 76 int fd_nfiles; /* number of open files allocated */ 77 NDSLOTTYPE *fd_map; /* bitmap of free fds */ 78 int fd_lastfile; /* high-water mark of fd_ofiles */ 79 int fd_freefile; /* approx. next free file */ 80 u_short fd_cmask; /* mask for file creation */ 81 u_short fd_refcnt; /* thread reference count */ 82 u_short fd_holdcnt; /* hold count on structure + mutex */ 83 struct sx fd_sx; /* protects members of this struct */ 84 struct kqlist fd_kqlist; /* list of kqueues on this filedesc */ 85 int fd_holdleaderscount; /* block fdfree() for shared close() */ 86 int fd_holdleaderswakeup; /* fdfree() needs wakeup */ 87}; 88#define fd_seq(fdp, fd) (&(fdp)->fd_ofiles[(fd)].fde_seq) 89 90/* 91 * Structure to keep track of (process leader, struct fildedesc) tuples. 92 * Each process has a pointer to such a structure when detailed tracking 93 * is needed, e.g., when rfork(RFPROC | RFMEM) causes a file descriptor 94 * table to be shared by processes having different "p_leader" pointers 95 * and thus distinct POSIX style locks. 96 * 97 * fdl_refcount and fdl_holdcount are protected by struct filedesc mtx. 98 */ 99struct filedesc_to_leader { 100 int fdl_refcount; /* references from struct proc */ 101 int fdl_holdcount; /* temporary hold during closef */ 102 int fdl_wakeup; /* fdfree() waits on closef() */ 103 struct proc *fdl_leader; /* owner of POSIX locks */ 104 /* Circular list: */ 105 struct filedesc_to_leader *fdl_prev; 106 struct filedesc_to_leader *fdl_next; 107}; 108 109/* 110 * Per-process open flags. 111 */ 112#define UF_EXCLOSE 0x01 /* auto-close on exec */ 113 114#ifdef _KERNEL 115 116/* Flags for do_dup() */ 117#define DUP_FIXED 0x1 /* Force fixed allocation. */ 118#define DUP_FCNTL 0x2 /* fcntl()-style errors. */ 119#define DUP_CLOEXEC 0x4 /* Atomically set FD_CLOEXEC. */ 120 121/* Lock a file descriptor table. */ 122#define FILEDESC_LOCK_INIT(fdp) sx_init(&(fdp)->fd_sx, "filedesc structure") 123#define FILEDESC_LOCK_DESTROY(fdp) sx_destroy(&(fdp)->fd_sx) 124#define FILEDESC_LOCK(fdp) (&(fdp)->fd_sx) 125#define FILEDESC_XLOCK(fdp) sx_xlock(&(fdp)->fd_sx) 126#define FILEDESC_XUNLOCK(fdp) sx_xunlock(&(fdp)->fd_sx) 127#define FILEDESC_SLOCK(fdp) sx_slock(&(fdp)->fd_sx) 128#define FILEDESC_SUNLOCK(fdp) sx_sunlock(&(fdp)->fd_sx) 129 130#define FILEDESC_LOCK_ASSERT(fdp) sx_assert(&(fdp)->fd_sx, SX_LOCKED | \ 131 SX_NOTRECURSED) 132#define FILEDESC_XLOCK_ASSERT(fdp) sx_assert(&(fdp)->fd_sx, SX_XLOCKED | \ 133 SX_NOTRECURSED) 134#define FILEDESC_UNLOCK_ASSERT(fdp) sx_assert(&(fdp)->fd_sx, SX_UNLOCKED) 135 136struct thread; 137 138void filecaps_init(struct filecaps *fcaps); 139void filecaps_copy(const struct filecaps *src, struct filecaps *dst); 140void filecaps_move(struct filecaps *src, struct filecaps *dst); 141void filecaps_free(struct filecaps *fcaps); 142 143int closef(struct file *fp, struct thread *td); 144int do_dup(struct thread *td, int flags, int old, int new, 145 register_t *retval); 146int dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode, 147 int openerror, int *indxp); 148int falloc(struct thread *td, struct file **resultfp, int *resultfd, 149 int flags); 150int falloc_noinstall(struct thread *td, struct file **resultfp); 151int finstall(struct thread *td, struct file *fp, int *resultfp, int flags, 152 struct filecaps *fcaps); 153int fdalloc(struct thread *td, int minfd, int *result); 154int fdallocn(struct thread *td, int minfd, int *fds, int n); 155int fdavail(struct thread *td, int n); 156int fdcheckstd(struct thread *td); 157void fdclose(struct thread *td, struct file *fp, int idx); 158void fdcloseexec(struct thread *td); 159struct filedesc *fdcopy(struct filedesc *fdp); 160void fdunshare(struct thread *td); 161void fdescfree(struct thread *td); 162struct filedesc *fdinit(struct filedesc *fdp); 163struct filedesc *fdshare(struct filedesc *fdp); 164struct filedesc_to_leader * 165 filedesc_to_leader_alloc(struct filedesc_to_leader *old, 166 struct filedesc *fdp, struct proc *leader); 167int getvnode(struct filedesc *fdp, int fd, cap_rights_t *rightsp, 168 struct file **fpp); 169void mountcheckdirs(struct vnode *olddp, struct vnode *newdp); 170void setugidsafety(struct thread *td); 171 172/* Return a referenced file from an unlocked descriptor. */ 173int fget_unlocked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, 174 int needfcntl, struct file **fpp, cap_rights_t *haverightsp); 175 176/* Requires a FILEDESC_{S,X}LOCK held and returns without a ref. */ 177static __inline struct file * 178fget_locked(struct filedesc *fdp, int fd) 179{ 180 181 FILEDESC_LOCK_ASSERT(fdp); 182 183 if (fd < 0 || fd > fdp->fd_lastfile) 184 return (NULL); 185 186 return (fdp->fd_ofiles[fd].fde_file); 187} 188 189#endif /* _KERNEL */ 190 191#endif /* !_SYS_FILEDESC_H_ */ 192