2 * Copyright (c) 1990, 1993
3 * The Regents of the University of California. All rights reserved.
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29 * @(#)filedesc.h 8.1 (Berkeley) 6/2/93
33 #ifndef _SYS_FILEDESC_H_
34 #define _SYS_FILEDESC_H_
36 #include <sys/caprights.h>
37 #include <sys/queue.h>
38 #include <sys/event.h>
40 #include <sys/priority.h>
44 #include <machine/_limits.h>
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 */
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 */
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))
66 * This structure is used for the management of descriptors. It may be
67 * shared by multiple processes.
69 #define NDSLOTTYPE u_long
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 */
88 #define fd_seq(fdp, fd) (&(fdp)->fd_ofiles[(fd)].fde_seq)
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.
97 * fdl_refcount and fdl_holdcount are protected by struct filedesc mtx.
99 struct 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 */
105 struct filedesc_to_leader *fdl_prev;
106 struct filedesc_to_leader *fdl_next;
110 * Per-process open flags.
112 #define UF_EXCLOSE 0x01 /* auto-close on exec */
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. */
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)
130 #define FILEDESC_LOCK_ASSERT(fdp) sx_assert(&(fdp)->fd_sx, SX_LOCKED | \
132 #define FILEDESC_XLOCK_ASSERT(fdp) sx_assert(&(fdp)->fd_sx, SX_XLOCKED | \
134 #define FILEDESC_UNLOCK_ASSERT(fdp) sx_assert(&(fdp)->fd_sx, SX_UNLOCKED)
138 void filecaps_init(struct filecaps *fcaps);
139 void filecaps_copy(const struct filecaps *src, struct filecaps *dst);
140 void filecaps_move(struct filecaps *src, struct filecaps *dst);
141 void filecaps_free(struct filecaps *fcaps);
143 int closef(struct file *fp, struct thread *td);
144 int do_dup(struct thread *td, int flags, int old, int new,
146 int dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode,
147 int openerror, int *indxp);
148 int falloc(struct thread *td, struct file **resultfp, int *resultfd,
150 int falloc_noinstall(struct thread *td, struct file **resultfp);
151 int finstall(struct thread *td, struct file *fp, int *resultfp, int flags,
152 struct filecaps *fcaps);
153 int fdalloc(struct thread *td, int minfd, int *result);
154 int fdallocn(struct thread *td, int minfd, int *fds, int n);
155 int fdavail(struct thread *td, int n);
156 int fdcheckstd(struct thread *td);
157 void fdclose(struct filedesc *fdp, struct file *fp, int idx, struct thread *td);
158 void fdcloseexec(struct thread *td);
159 struct filedesc *fdcopy(struct filedesc *fdp);
160 void fdunshare(struct thread *td);
161 void fdescfree(struct thread *td);
162 struct filedesc *fdinit(struct filedesc *fdp);
163 struct filedesc *fdshare(struct filedesc *fdp);
164 struct filedesc_to_leader *
165 filedesc_to_leader_alloc(struct filedesc_to_leader *old,
166 struct filedesc *fdp, struct proc *leader);
167 int getvnode(struct filedesc *fdp, int fd, cap_rights_t *rightsp,
169 void mountcheckdirs(struct vnode *olddp, struct vnode *newdp);
170 void setugidsafety(struct thread *td);
172 /* Return a referenced file from an unlocked descriptor. */
173 int fget_unlocked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp,
174 int needfcntl, struct file **fpp, cap_rights_t *haverightsp);
176 /* Requires a FILEDESC_{S,X}LOCK held and returns without a ref. */
177 static __inline struct file *
178 fget_locked(struct filedesc *fdp, int fd)
181 FILEDESC_LOCK_ASSERT(fdp);
183 if (fd < 0 || fd > fdp->fd_lastfile)
186 return (fdp->fd_ofiles[fd].fde_file);
191 #endif /* !_SYS_FILEDESC_H_ */