1139804Simp/*- 213675Sdyson * Copyright (c) 1996 John S. Dyson 313675Sdyson * All rights reserved. 413675Sdyson * 513675Sdyson * Redistribution and use in source and binary forms, with or without 613675Sdyson * modification, are permitted provided that the following conditions 713675Sdyson * are met: 813675Sdyson * 1. Redistributions of source code must retain the above copyright 913675Sdyson * notice immediately at the beginning of the file, without modification, 1013675Sdyson * this list of conditions, and the following disclaimer. 1113675Sdyson * 2. Redistributions in binary form must reproduce the above copyright 1213675Sdyson * notice, this list of conditions and the following disclaimer in the 1313675Sdyson * documentation and/or other materials provided with the distribution. 1413675Sdyson * 3. Absolutely no warranty of function or purpose is made by the author 1513675Sdyson * John S. Dyson. 1614037Sdyson * 4. Modifications may be freely made to this file if the above conditions 1713675Sdyson * are met. 1813675Sdyson */ 1913675Sdyson 2013675Sdyson/* 2113675Sdyson * This file contains a high-performance replacement for the socket-based 2213675Sdyson * pipes scheme originally used in FreeBSD/4.4Lite. It does not support 2313675Sdyson * all features of sockets, but does do everything that pipes normally 2413675Sdyson * do. 2513675Sdyson */ 2613675Sdyson 2713907Sdyson/* 2813907Sdyson * This code has two modes of operation, a small write mode and a large 2913907Sdyson * write mode. The small write mode acts like conventional pipes with 3013907Sdyson * a kernel buffer. If the buffer is less than PIPE_MINDIRECT, then the 3113907Sdyson * "normal" pipe buffering is done. If the buffer is between PIPE_MINDIRECT 32219801Salc * and PIPE_SIZE in size, the sending process pins the underlying pages in 33219801Salc * memory, and the receiving process copies directly from these pinned pages 34219801Salc * in the sending process. 3513907Sdyson * 3613907Sdyson * If the sending process receives a signal, it is possible that it will 3713913Sdyson * go away, and certainly its address space can change, because control 3813907Sdyson * is returned back to the user-mode side. In that case, the pipe code 3913907Sdyson * arranges to copy the buffer supplied by the user process, to a pageable 4013907Sdyson * kernel buffer, and the receiving process will grab the data from the 4113907Sdyson * pageable kernel buffer. Since signals don't happen all that often, 4213907Sdyson * the copy operation is normally eliminated. 4313907Sdyson * 4413907Sdyson * The constant PIPE_MINDIRECT is chosen to make sure that buffering will 4513907Sdyson * happen for small transfers so that the system will not spend all of 46118764Ssilby * its time context switching. 47117325Ssilby * 48118764Ssilby * In order to limit the resource use of pipes, two sysctls exist: 49117325Ssilby * 50118764Ssilby * kern.ipc.maxpipekva - This is a hard limit on the amount of pageable 51133790Ssilby * address space available to us in pipe_map. This value is normally 52133790Ssilby * autotuned, but may also be loader tuned. 53117325Ssilby * 54133790Ssilby * kern.ipc.pipekva - This read-only sysctl tracks the current amount of 55133790Ssilby * memory in use by pipes. 56117325Ssilby * 57133790Ssilby * Based on how large pipekva is relative to maxpipekva, the following 58133790Ssilby * will happen: 59117325Ssilby * 60133790Ssilby * 0% - 50%: 61133790Ssilby * New pipes are given 16K of memory backing, pipes may dynamically 62133790Ssilby * grow to as large as 64K where needed. 63133790Ssilby * 50% - 75%: 64133790Ssilby * New pipes are given 4K (or PAGE_SIZE) of memory backing, 65133790Ssilby * existing pipes may NOT grow. 66133790Ssilby * 75% - 100%: 67133790Ssilby * New pipes are given 4K (or PAGE_SIZE) of memory backing, 68133790Ssilby * existing pipes will be shrunk down to 4K whenever possible. 69133049Ssilby * 70133790Ssilby * Resizing may be disabled by setting kern.ipc.piperesizeallowed=0. If 71133790Ssilby * that is set, the only resize that will occur is the 0 -> SMALL_PIPE_SIZE 72133790Ssilby * resize which MUST occur for reverse-direction pipes when they are 73133790Ssilby * first used. 74133790Ssilby * 75133790Ssilby * Additional information about the current state of pipes may be obtained 76133790Ssilby * from kern.ipc.pipes, kern.ipc.pipefragretry, kern.ipc.pipeallocfail, 77133790Ssilby * and kern.ipc.piperesizefail. 78133790Ssilby * 79133049Ssilby * Locking rules: There are two locks present here: A mutex, used via 80133049Ssilby * PIPE_LOCK, and a flag, used via pipelock(). All locking is done via 81133049Ssilby * the flag, as mutexes can not persist over uiomove. The mutex 82133049Ssilby * exists only to guard access to the flag, and is not in itself a 83133790Ssilby * locking mechanism. Also note that there is only a single mutex for 84133790Ssilby * both directions of a pipe. 85133049Ssilby * 86133049Ssilby * As pipelock() may have to sleep before it can acquire the flag, it 87133049Ssilby * is important to reread all data after a call to pipelock(); everything 88133049Ssilby * in the structure may have changed. 8913907Sdyson */ 9013907Sdyson 91116182Sobrien#include <sys/cdefs.h> 92116182Sobrien__FBSDID("$FreeBSD$"); 93116182Sobrien 9413675Sdyson#include <sys/param.h> 9513675Sdyson#include <sys/systm.h> 96226578Skib#include <sys/conf.h> 9724131Sbde#include <sys/fcntl.h> 9813675Sdyson#include <sys/file.h> 9913675Sdyson#include <sys/filedesc.h> 10024206Sbde#include <sys/filio.h> 10191372Salfred#include <sys/kernel.h> 10276166Smarkm#include <sys/lock.h> 10376827Salfred#include <sys/mutex.h> 10424206Sbde#include <sys/ttycom.h> 10513675Sdyson#include <sys/stat.h> 10691968Salfred#include <sys/malloc.h> 10729356Speter#include <sys/poll.h> 10870834Swollman#include <sys/selinfo.h> 10913675Sdyson#include <sys/signalvar.h> 110184849Sed#include <sys/syscallsubr.h> 111117325Ssilby#include <sys/sysctl.h> 11213675Sdyson#include <sys/sysproto.h> 11313675Sdyson#include <sys/pipe.h> 11476166Smarkm#include <sys/proc.h> 11555112Sbde#include <sys/vnode.h> 11634924Sbde#include <sys/uio.h> 11759288Sjlemon#include <sys/event.h> 11813675Sdyson 119163606Srwatson#include <security/mac/mac_framework.h> 120163606Srwatson 12113675Sdyson#include <vm/vm.h> 12213675Sdyson#include <vm/vm_param.h> 12313675Sdyson#include <vm/vm_object.h> 12413675Sdyson#include <vm/vm_kern.h> 12513675Sdyson#include <vm/vm_extern.h> 12613675Sdyson#include <vm/pmap.h> 12713675Sdyson#include <vm/vm_map.h> 12813907Sdyson#include <vm/vm_page.h> 12992751Sjeff#include <vm/uma.h> 13013675Sdyson 131248532Sjkim/* XXX */ 132248532Sjkimint do_pipe(struct thread *td, int fildes[2], int flags); 133248532Sjkim 13414037Sdyson/* 13514037Sdyson * Use this define if you want to disable *fancy* VM things. Expect an 13614037Sdyson * approx 30% decrease in transfer rate. This could be useful for 13714037Sdyson * NetBSD or OpenBSD. 13814037Sdyson */ 13914037Sdyson/* #define PIPE_NODIRECT */ 14014037Sdyson 14114037Sdyson/* 14214037Sdyson * interfaces to the outside world 14314037Sdyson */ 144108255Sphkstatic fo_rdwr_t pipe_read; 145108255Sphkstatic fo_rdwr_t pipe_write; 146175140Sjhbstatic fo_truncate_t pipe_truncate; 147108255Sphkstatic fo_ioctl_t pipe_ioctl; 148108255Sphkstatic fo_poll_t pipe_poll; 149108255Sphkstatic fo_kqfilter_t pipe_kqfilter; 150108255Sphkstatic fo_stat_t pipe_stat; 151108255Sphkstatic fo_close_t pipe_close; 15213675Sdyson 15372521Sjlemonstatic struct fileops pipeops = { 154116546Sphk .fo_read = pipe_read, 155116546Sphk .fo_write = pipe_write, 156175140Sjhb .fo_truncate = pipe_truncate, 157116546Sphk .fo_ioctl = pipe_ioctl, 158116546Sphk .fo_poll = pipe_poll, 159116546Sphk .fo_kqfilter = pipe_kqfilter, 160116546Sphk .fo_stat = pipe_stat, 161116546Sphk .fo_close = pipe_close, 162224914Skib .fo_chmod = invfo_chmod, 163224914Skib .fo_chown = invfo_chown, 164116546Sphk .fo_flags = DFLAG_PASSABLE 16572521Sjlemon}; 16613675Sdyson 16759288Sjlemonstatic void filt_pipedetach(struct knote *kn); 16859288Sjlemonstatic int filt_piperead(struct knote *kn, long hint); 16959288Sjlemonstatic int filt_pipewrite(struct knote *kn, long hint); 17059288Sjlemon 171197134Srwatsonstatic struct filterops pipe_rfiltops = { 172197134Srwatson .f_isfd = 1, 173197134Srwatson .f_detach = filt_pipedetach, 174197134Srwatson .f_event = filt_piperead 175197134Srwatson}; 176197134Srwatsonstatic struct filterops pipe_wfiltops = { 177197134Srwatson .f_isfd = 1, 178197134Srwatson .f_detach = filt_pipedetach, 179197134Srwatson .f_event = filt_pipewrite 180197134Srwatson}; 18159288Sjlemon 18213675Sdyson/* 18313675Sdyson * Default pipe buffer size(s), this can be kind-of large now because pipe 18413675Sdyson * space is pageable. The pipe code will try to maintain locality of 18513675Sdyson * reference for performance reasons, so small amounts of outstanding I/O 18613675Sdyson * will not wipe the cache. 18713675Sdyson */ 18813907Sdyson#define MINPIPESIZE (PIPE_SIZE/3) 18913907Sdyson#define MAXPIPESIZE (2*PIPE_SIZE/3) 19013675Sdyson 191189649Sjhbstatic long amountpipekva; 192133790Ssilbystatic int pipefragretry; 193133790Ssilbystatic int pipeallocfail; 194133790Ssilbystatic int piperesizefail; 195133790Ssilbystatic int piperesizeallowed = 1; 19613907Sdyson 197189649SjhbSYSCTL_LONG(_kern_ipc, OID_AUTO, maxpipekva, CTLFLAG_RDTUN, 198117325Ssilby &maxpipekva, 0, "Pipe KVA limit"); 199189649SjhbSYSCTL_LONG(_kern_ipc, OID_AUTO, pipekva, CTLFLAG_RD, 200117325Ssilby &amountpipekva, 0, "Pipe KVA usage"); 201133790SsilbySYSCTL_INT(_kern_ipc, OID_AUTO, pipefragretry, CTLFLAG_RD, 202133790Ssilby &pipefragretry, 0, "Pipe allocation retries due to fragmentation"); 203133790SsilbySYSCTL_INT(_kern_ipc, OID_AUTO, pipeallocfail, CTLFLAG_RD, 204133790Ssilby &pipeallocfail, 0, "Pipe allocation failures"); 205133790SsilbySYSCTL_INT(_kern_ipc, OID_AUTO, piperesizefail, CTLFLAG_RD, 206133790Ssilby &piperesizefail, 0, "Pipe resize failures"); 207133790SsilbySYSCTL_INT(_kern_ipc, OID_AUTO, piperesizeallowed, CTLFLAG_RW, 208133790Ssilby &piperesizeallowed, 0, "Pipe resizing allowed"); 209117325Ssilby 21091413Salfredstatic void pipeinit(void *dummy __unused); 21191413Salfredstatic void pipeclose(struct pipe *cpipe); 21291413Salfredstatic void pipe_free_kmem(struct pipe *cpipe); 213133790Ssilbystatic int pipe_create(struct pipe *pipe, int backing); 21491413Salfredstatic __inline int pipelock(struct pipe *cpipe, int catch); 21591413Salfredstatic __inline void pipeunlock(struct pipe *cpipe); 21691413Salfredstatic __inline void pipeselwakeup(struct pipe *cpipe); 21714037Sdyson#ifndef PIPE_NODIRECT 21891413Salfredstatic int pipe_build_write_buffer(struct pipe *wpipe, struct uio *uio); 21991413Salfredstatic void pipe_destroy_write_buffer(struct pipe *wpipe); 22091413Salfredstatic int pipe_direct_write(struct pipe *wpipe, struct uio *uio); 22191413Salfredstatic void pipe_clone_write_buffer(struct pipe *wpipe); 22214037Sdyson#endif 22391413Salfredstatic int pipespace(struct pipe *cpipe, int size); 224132579Srwatsonstatic int pipespace_new(struct pipe *cpipe, int size); 22513675Sdyson 226132987Sgreenstatic int pipe_zone_ctor(void *mem, int size, void *arg, int flags); 227132987Sgreenstatic int pipe_zone_init(void *mem, int size, int flags); 228125293Srwatsonstatic void pipe_zone_fini(void *mem, int size); 229125293Srwatson 23092751Sjeffstatic uma_zone_t pipe_zone; 231226578Skibstatic struct unrhdr *pipeino_unr; 232226578Skibstatic dev_t pipedev_ino; 23327899Sdyson 23491372SalfredSYSINIT(vfs, SI_SUB_VFS, SI_ORDER_ANY, pipeinit, NULL); 23591372Salfred 23691372Salfredstatic void 23791372Salfredpipeinit(void *dummy __unused) 23891372Salfred{ 239118880Salc 240170022Srwatson pipe_zone = uma_zcreate("pipe", sizeof(struct pipepair), 241170022Srwatson pipe_zone_ctor, NULL, pipe_zone_init, pipe_zone_fini, 242125293Srwatson UMA_ALIGN_PTR, 0); 243118880Salc KASSERT(pipe_zone != NULL, ("pipe_zone not initialized")); 244226578Skib pipeino_unr = new_unrhdr(1, INT32_MAX, NULL); 245226578Skib KASSERT(pipeino_unr != NULL, ("pipe fake inodes not initialized")); 246226578Skib pipedev_ino = devfs_alloc_cdp_inode(); 247226578Skib KASSERT(pipedev_ino > 0, ("pipe dev inode not initialized")); 24891372Salfred} 24991372Salfred 250132987Sgreenstatic int 251132987Sgreenpipe_zone_ctor(void *mem, int size, void *arg, int flags) 252125293Srwatson{ 253125293Srwatson struct pipepair *pp; 254125293Srwatson struct pipe *rpipe, *wpipe; 255125293Srwatson 256125293Srwatson KASSERT(size == sizeof(*pp), ("pipe_zone_ctor: wrong size")); 257125293Srwatson 258125293Srwatson pp = (struct pipepair *)mem; 259125293Srwatson 260125293Srwatson /* 261125293Srwatson * We zero both pipe endpoints to make sure all the kmem pointers 262125293Srwatson * are NULL, flag fields are zero'd, etc. We timestamp both 263125293Srwatson * endpoints with the same time. 264125293Srwatson */ 265125293Srwatson rpipe = &pp->pp_rpipe; 266125293Srwatson bzero(rpipe, sizeof(*rpipe)); 267125293Srwatson vfs_timestamp(&rpipe->pipe_ctime); 268125293Srwatson rpipe->pipe_atime = rpipe->pipe_mtime = rpipe->pipe_ctime; 269125293Srwatson 270125293Srwatson wpipe = &pp->pp_wpipe; 271125293Srwatson bzero(wpipe, sizeof(*wpipe)); 272125293Srwatson wpipe->pipe_ctime = rpipe->pipe_ctime; 273125293Srwatson wpipe->pipe_atime = wpipe->pipe_mtime = rpipe->pipe_ctime; 274125293Srwatson 275125293Srwatson rpipe->pipe_peer = wpipe; 276125293Srwatson rpipe->pipe_pair = pp; 277125293Srwatson wpipe->pipe_peer = rpipe; 278125293Srwatson wpipe->pipe_pair = pp; 279125293Srwatson 280125293Srwatson /* 281125293Srwatson * Mark both endpoints as present; they will later get free'd 282125293Srwatson * one at a time. When both are free'd, then the whole pair 283125293Srwatson * is released. 284125293Srwatson */ 285179243Skib rpipe->pipe_present = PIPE_ACTIVE; 286179243Skib wpipe->pipe_present = PIPE_ACTIVE; 287125293Srwatson 288125293Srwatson /* 289125293Srwatson * Eventually, the MAC Framework may initialize the label 290125293Srwatson * in ctor or init, but for now we do it elswhere to avoid 291125293Srwatson * blocking in ctor or init. 292125293Srwatson */ 293125293Srwatson pp->pp_label = NULL; 294125293Srwatson 295132987Sgreen return (0); 296125293Srwatson} 297125293Srwatson 298132987Sgreenstatic int 299132987Sgreenpipe_zone_init(void *mem, int size, int flags) 300125293Srwatson{ 301125293Srwatson struct pipepair *pp; 302125293Srwatson 303125293Srwatson KASSERT(size == sizeof(*pp), ("pipe_zone_init: wrong size")); 304125293Srwatson 305125293Srwatson pp = (struct pipepair *)mem; 306125293Srwatson 307125293Srwatson mtx_init(&pp->pp_mtx, "pipe mutex", NULL, MTX_DEF | MTX_RECURSE); 308132987Sgreen return (0); 309125293Srwatson} 310125293Srwatson 311125293Srwatsonstatic void 312125293Srwatsonpipe_zone_fini(void *mem, int size) 313125293Srwatson{ 314125293Srwatson struct pipepair *pp; 315125293Srwatson 316125293Srwatson KASSERT(size == sizeof(*pp), ("pipe_zone_fini: wrong size")); 317125293Srwatson 318125293Srwatson pp = (struct pipepair *)mem; 319125293Srwatson 320125293Srwatson mtx_destroy(&pp->pp_mtx); 321125293Srwatson} 322125293Srwatson 32313675Sdyson/* 324167232Srwatson * The pipe system call for the DTYPE_PIPE type of pipes. If we fail, let 325167232Srwatson * the zone pick up the pieces via pipeclose(). 32613675Sdyson */ 32713675Sdysonint 328184849Sedkern_pipe(struct thread *td, int fildes[2]) 32913675Sdyson{ 330248532Sjkim 331248532Sjkim return (do_pipe(td, fildes, 0)); 332248532Sjkim} 333248532Sjkim 334248532Sjkimint 335248532Sjkimdo_pipe(struct thread *td, int fildes[2], int flags) 336248532Sjkim{ 33783366Sjulian struct filedesc *fdp = td->td_proc->p_fd; 33813675Sdyson struct file *rf, *wf; 339125293Srwatson struct pipepair *pp; 34013675Sdyson struct pipe *rpipe, *wpipe; 341248532Sjkim int fd, fflags, error; 34227899Sdyson 343125293Srwatson pp = uma_zalloc(pipe_zone, M_WAITOK); 344125293Srwatson#ifdef MAC 345125293Srwatson /* 346126249Srwatson * The MAC label is shared between the connected endpoints. As a 347172930Srwatson * result mac_pipe_init() and mac_pipe_create() are called once 348126249Srwatson * for the pair, and not on the endpoints. 349125293Srwatson */ 350172930Srwatson mac_pipe_init(pp); 351172930Srwatson mac_pipe_create(td->td_ucred, pp); 352125293Srwatson#endif 353125293Srwatson rpipe = &pp->pp_rpipe; 354125293Srwatson wpipe = &pp->pp_wpipe; 355125293Srwatson 356193951Skib knlist_init_mtx(&rpipe->pipe_sel.si_note, PIPE_MTX(rpipe)); 357193951Skib knlist_init_mtx(&wpipe->pipe_sel.si_note, PIPE_MTX(wpipe)); 358140369Ssilby 359133790Ssilby /* Only the forward direction pipe is backed by default */ 360155035Sglebius if ((error = pipe_create(rpipe, 1)) != 0 || 361155035Sglebius (error = pipe_create(wpipe, 0)) != 0) { 362124394Sdes pipeclose(rpipe); 363124394Sdes pipeclose(wpipe); 364155035Sglebius return (error); 36576364Salfred } 366124394Sdes 36713907Sdyson rpipe->pipe_state |= PIPE_DIRECTOK; 36813907Sdyson wpipe->pipe_state |= PIPE_DIRECTOK; 36913675Sdyson 370248532Sjkim error = falloc(td, &rf, &fd, flags); 37170915Sdwmalone if (error) { 37270915Sdwmalone pipeclose(rpipe); 37370915Sdwmalone pipeclose(wpipe); 37470915Sdwmalone return (error); 37570915Sdwmalone } 376121256Sdwmalone /* An extra reference on `rf' has been held for us by falloc(). */ 377184849Sed fildes[0] = fd; 37870915Sdwmalone 379248532Sjkim fflags = FREAD | FWRITE; 380248532Sjkim if ((flags & O_NONBLOCK) != 0) 381248532Sjkim fflags |= FNONBLOCK; 382248532Sjkim 38370803Sdwmalone /* 38470803Sdwmalone * Warning: once we've gotten past allocation of the fd for the 38570803Sdwmalone * read-side, we can only drop the read side via fdrop() in order 38670803Sdwmalone * to avoid races against processes which manage to dup() the read 38770803Sdwmalone * side while we are blocked trying to allocate the write side. 38870803Sdwmalone */ 389248532Sjkim finit(rf, fflags, DTYPE_PIPE, rpipe, &pipeops); 390248532Sjkim error = falloc(td, &wf, &fd, flags); 39170915Sdwmalone if (error) { 392184849Sed fdclose(fdp, rf, fildes[0], td); 39383366Sjulian fdrop(rf, td); 39470915Sdwmalone /* rpipe has been closed by fdrop(). */ 39570915Sdwmalone pipeclose(wpipe); 39670915Sdwmalone return (error); 39770915Sdwmalone } 398121256Sdwmalone /* An extra reference on `wf' has been held for us by falloc(). */ 399248532Sjkim finit(wf, fflags, DTYPE_PIPE, wpipe, &pipeops); 400121256Sdwmalone fdrop(wf, td); 401184849Sed fildes[1] = fd; 40283366Sjulian fdrop(rf, td); 40313675Sdyson 40413675Sdyson return (0); 40513675Sdyson} 40613675Sdyson 407184849Sed/* ARGSUSED */ 408184849Sedint 409225617Skmacysys_pipe(struct thread *td, struct pipe_args *uap) 410184849Sed{ 411184849Sed int error; 412184849Sed int fildes[2]; 413184849Sed 414184849Sed error = kern_pipe(td, fildes); 415184849Sed if (error) 416184849Sed return (error); 417184849Sed 418184849Sed td->td_retval[0] = fildes[0]; 419184849Sed td->td_retval[1] = fildes[1]; 420184849Sed 421184849Sed return (0); 422184849Sed} 423184849Sed 42413909Sdyson/* 42513909Sdyson * Allocate kva for pipe circular buffer, the space is pageable 42676364Salfred * This routine will 'realloc' the size of a pipe safely, if it fails 42776364Salfred * it will retain the old buffer. 42876364Salfred * If it fails it will return ENOMEM. 42913909Sdyson */ 43076364Salfredstatic int 431132579Srwatsonpipespace_new(cpipe, size) 43213675Sdyson struct pipe *cpipe; 43376364Salfred int size; 43413675Sdyson{ 43576364Salfred caddr_t buffer; 436133790Ssilby int error, cnt, firstseg; 437117325Ssilby static int curfail = 0; 438117325Ssilby static struct timeval lastfail; 43913675Sdyson 440125293Srwatson KASSERT(!mtx_owned(PIPE_MTX(cpipe)), ("pipespace: pipe mutex locked")); 441133790Ssilby KASSERT(!(cpipe->pipe_state & PIPE_DIRECTW), 442133790Ssilby ("pipespace: resize of direct writes not allowed")); 443133790Ssilbyretry: 444133790Ssilby cnt = cpipe->pipe_buffer.cnt; 445133790Ssilby if (cnt > size) 446133790Ssilby size = cnt; 44779224Sdillon 448118764Ssilby size = round_page(size); 449118764Ssilby buffer = (caddr_t) vm_map_min(pipe_map); 45013675Sdyson 451122163Salc error = vm_map_find(pipe_map, NULL, 0, 45276364Salfred (vm_offset_t *) &buffer, size, 1, 45313688Sdyson VM_PROT_ALL, VM_PROT_ALL, 0); 45476364Salfred if (error != KERN_SUCCESS) { 455133790Ssilby if ((cpipe->pipe_buffer.buffer == NULL) && 456133790Ssilby (size > SMALL_PIPE_SIZE)) { 457133790Ssilby size = SMALL_PIPE_SIZE; 458133790Ssilby pipefragretry++; 459133790Ssilby goto retry; 460133790Ssilby } 461133790Ssilby if (cpipe->pipe_buffer.buffer == NULL) { 462133790Ssilby pipeallocfail++; 463133790Ssilby if (ppsratecheck(&lastfail, &curfail, 1)) 464133790Ssilby printf("kern.ipc.maxpipekva exceeded; see tuning(7)\n"); 465133790Ssilby } else { 466133790Ssilby piperesizefail++; 467133790Ssilby } 46876364Salfred return (ENOMEM); 46976364Salfred } 47076364Salfred 471133790Ssilby /* copy data, then free old resources if we're resizing */ 472133790Ssilby if (cnt > 0) { 473133790Ssilby if (cpipe->pipe_buffer.in <= cpipe->pipe_buffer.out) { 474133790Ssilby firstseg = cpipe->pipe_buffer.size - cpipe->pipe_buffer.out; 475133790Ssilby bcopy(&cpipe->pipe_buffer.buffer[cpipe->pipe_buffer.out], 476133790Ssilby buffer, firstseg); 477133790Ssilby if ((cnt - firstseg) > 0) 478133790Ssilby bcopy(cpipe->pipe_buffer.buffer, &buffer[firstseg], 479133790Ssilby cpipe->pipe_buffer.in); 480133790Ssilby } else { 481133790Ssilby bcopy(&cpipe->pipe_buffer.buffer[cpipe->pipe_buffer.out], 482133790Ssilby buffer, cnt); 483133790Ssilby } 484133790Ssilby } 48576364Salfred pipe_free_kmem(cpipe); 48676364Salfred cpipe->pipe_buffer.buffer = buffer; 48776364Salfred cpipe->pipe_buffer.size = size; 488133790Ssilby cpipe->pipe_buffer.in = cnt; 48976364Salfred cpipe->pipe_buffer.out = 0; 490133790Ssilby cpipe->pipe_buffer.cnt = cnt; 491189649Sjhb atomic_add_long(&amountpipekva, cpipe->pipe_buffer.size); 49276364Salfred return (0); 49313907Sdyson} 49413688Sdyson 49513907Sdyson/* 496132579Srwatson * Wrapper for pipespace_new() that performs locking assertions. 497132579Srwatson */ 498132579Srwatsonstatic int 499132579Srwatsonpipespace(cpipe, size) 500132579Srwatson struct pipe *cpipe; 501132579Srwatson int size; 502132579Srwatson{ 503132579Srwatson 504133049Ssilby KASSERT(cpipe->pipe_state & PIPE_LOCKFL, 505133049Ssilby ("Unlocked pipe passed to pipespace")); 506132579Srwatson return (pipespace_new(cpipe, size)); 507132579Srwatson} 508132579Srwatson 509132579Srwatson/* 51013675Sdyson * lock a pipe for I/O, blocking other access 51113675Sdyson */ 51213675Sdysonstatic __inline int 51313907Sdysonpipelock(cpipe, catch) 51413675Sdyson struct pipe *cpipe; 51513907Sdyson int catch; 51613675Sdyson{ 51713776Sdyson int error; 51876364Salfred 51991362Salfred PIPE_LOCK_ASSERT(cpipe, MA_OWNED); 52091362Salfred while (cpipe->pipe_state & PIPE_LOCKFL) { 52113675Sdyson cpipe->pipe_state |= PIPE_LWANT; 52291362Salfred error = msleep(cpipe, PIPE_MTX(cpipe), 52391362Salfred catch ? (PRIBIO | PCATCH) : PRIBIO, 52476760Salfred "pipelk", 0); 525124394Sdes if (error != 0) 52676760Salfred return (error); 52713675Sdyson } 52891362Salfred cpipe->pipe_state |= PIPE_LOCKFL; 52976760Salfred return (0); 53013675Sdyson} 53113675Sdyson 53213675Sdyson/* 53313675Sdyson * unlock a pipe I/O lock 53413675Sdyson */ 53513675Sdysonstatic __inline void 53613675Sdysonpipeunlock(cpipe) 53713675Sdyson struct pipe *cpipe; 53813675Sdyson{ 53976364Salfred 54091362Salfred PIPE_LOCK_ASSERT(cpipe, MA_OWNED); 541133049Ssilby KASSERT(cpipe->pipe_state & PIPE_LOCKFL, 542133049Ssilby ("Unlocked pipe passed to pipeunlock")); 54391362Salfred cpipe->pipe_state &= ~PIPE_LOCKFL; 54413675Sdyson if (cpipe->pipe_state & PIPE_LWANT) { 54513675Sdyson cpipe->pipe_state &= ~PIPE_LWANT; 54614177Sdyson wakeup(cpipe); 54713675Sdyson } 54813675Sdyson} 54913675Sdyson 55014037Sdysonstatic __inline void 55114037Sdysonpipeselwakeup(cpipe) 55214037Sdyson struct pipe *cpipe; 55314037Sdyson{ 55476364Salfred 555126252Srwatson PIPE_LOCK_ASSERT(cpipe, MA_OWNED); 55614037Sdyson if (cpipe->pipe_state & PIPE_SEL) { 557122352Stanimura selwakeuppri(&cpipe->pipe_sel, PSOCK); 558174647Sjeff if (!SEL_WAITING(&cpipe->pipe_sel)) 559174647Sjeff cpipe->pipe_state &= ~PIPE_SEL; 56014037Sdyson } 56141086Struckman if ((cpipe->pipe_state & PIPE_ASYNC) && cpipe->pipe_sigio) 56295883Salfred pgsigio(&cpipe->pipe_sigio, SIGIO, 0); 563133741Sjmg KNOTE_LOCKED(&cpipe->pipe_sel.si_note, 0); 56414037Sdyson} 56514037Sdyson 566126131Sgreen/* 567126131Sgreen * Initialize and allocate VM and memory for pipe. The structure 568126131Sgreen * will start out zero'd from the ctor, so we just manage the kmem. 569126131Sgreen */ 570126131Sgreenstatic int 571133790Ssilbypipe_create(pipe, backing) 572126131Sgreen struct pipe *pipe; 573133790Ssilby int backing; 574126131Sgreen{ 575126131Sgreen int error; 576126131Sgreen 577133790Ssilby if (backing) { 578133790Ssilby if (amountpipekva > maxpipekva / 2) 579133790Ssilby error = pipespace_new(pipe, SMALL_PIPE_SIZE); 580133790Ssilby else 581133790Ssilby error = pipespace_new(pipe, PIPE_SIZE); 582133790Ssilby } else { 583133790Ssilby /* If we're not backing this pipe, no need to do anything. */ 584133790Ssilby error = 0; 585133790Ssilby } 586229248Skib pipe->pipe_ino = -1; 587132579Srwatson return (error); 588126131Sgreen} 589126131Sgreen 59013675Sdyson/* ARGSUSED */ 59113675Sdysonstatic int 592101941Srwatsonpipe_read(fp, uio, active_cred, flags, td) 59313675Sdyson struct file *fp; 59413675Sdyson struct uio *uio; 595101941Srwatson struct ucred *active_cred; 59683366Sjulian struct thread *td; 59745311Sdt int flags; 59813675Sdyson{ 599109153Sdillon struct pipe *rpipe = fp->f_data; 60047748Salc int error; 60113675Sdyson int nread = 0; 602233353Skib int size; 60313675Sdyson 60491362Salfred PIPE_LOCK(rpipe); 60513675Sdyson ++rpipe->pipe_busy; 60647748Salc error = pipelock(rpipe, 1); 60747748Salc if (error) 60847748Salc goto unlocked_error; 60947748Salc 610101768Srwatson#ifdef MAC 611172930Srwatson error = mac_pipe_check_read(active_cred, rpipe->pipe_pair); 612101768Srwatson if (error) 613101768Srwatson goto locked_error; 614101768Srwatson#endif 615133790Ssilby if (amountpipekva > (3 * maxpipekva) / 4) { 616133790Ssilby if (!(rpipe->pipe_state & PIPE_DIRECTW) && 617133790Ssilby (rpipe->pipe_buffer.size > SMALL_PIPE_SIZE) && 618133790Ssilby (rpipe->pipe_buffer.cnt <= SMALL_PIPE_SIZE) && 619133790Ssilby (piperesizeallowed == 1)) { 620133790Ssilby PIPE_UNLOCK(rpipe); 621133790Ssilby pipespace(rpipe, SMALL_PIPE_SIZE); 622133790Ssilby PIPE_LOCK(rpipe); 623133790Ssilby } 624133790Ssilby } 625101768Srwatson 62613675Sdyson while (uio->uio_resid) { 62713907Sdyson /* 62813907Sdyson * normal pipe buffer receive 62913907Sdyson */ 63013675Sdyson if (rpipe->pipe_buffer.cnt > 0) { 63118863Sdyson size = rpipe->pipe_buffer.size - rpipe->pipe_buffer.out; 63213675Sdyson if (size > rpipe->pipe_buffer.cnt) 63313675Sdyson size = rpipe->pipe_buffer.cnt; 634233353Skib if (size > uio->uio_resid) 635233353Skib size = uio->uio_resid; 63647748Salc 63791362Salfred PIPE_UNLOCK(rpipe); 638116127Smux error = uiomove( 639116127Smux &rpipe->pipe_buffer.buffer[rpipe->pipe_buffer.out], 640116127Smux size, uio); 64191362Salfred PIPE_LOCK(rpipe); 64276760Salfred if (error) 64313675Sdyson break; 64476760Salfred 64513675Sdyson rpipe->pipe_buffer.out += size; 64613675Sdyson if (rpipe->pipe_buffer.out >= rpipe->pipe_buffer.size) 64713675Sdyson rpipe->pipe_buffer.out = 0; 64813675Sdyson 64913675Sdyson rpipe->pipe_buffer.cnt -= size; 65047748Salc 65147748Salc /* 65247748Salc * If there is no more to read in the pipe, reset 65347748Salc * its pointers to the beginning. This improves 65447748Salc * cache hit stats. 65547748Salc */ 65647748Salc if (rpipe->pipe_buffer.cnt == 0) { 65747748Salc rpipe->pipe_buffer.in = 0; 65847748Salc rpipe->pipe_buffer.out = 0; 65947748Salc } 66013675Sdyson nread += size; 66114037Sdyson#ifndef PIPE_NODIRECT 66213907Sdyson /* 66313907Sdyson * Direct copy, bypassing a kernel buffer. 66413907Sdyson */ 66513907Sdyson } else if ((size = rpipe->pipe_map.cnt) && 66647748Salc (rpipe->pipe_state & PIPE_DIRECTW)) { 667233353Skib if (size > uio->uio_resid) 66818863Sdyson size = (u_int) uio->uio_resid; 66947748Salc 67091362Salfred PIPE_UNLOCK(rpipe); 671127501Salc error = uiomove_fromphys(rpipe->pipe_map.ms, 672127501Salc rpipe->pipe_map.pos, size, uio); 67391362Salfred PIPE_LOCK(rpipe); 67413907Sdyson if (error) 67513907Sdyson break; 67613907Sdyson nread += size; 67713907Sdyson rpipe->pipe_map.pos += size; 67813907Sdyson rpipe->pipe_map.cnt -= size; 67913907Sdyson if (rpipe->pipe_map.cnt == 0) { 68013907Sdyson rpipe->pipe_state &= ~PIPE_DIRECTW; 68113907Sdyson wakeup(rpipe); 68213907Sdyson } 68314037Sdyson#endif 68413675Sdyson } else { 68513675Sdyson /* 68613675Sdyson * detect EOF condition 68776760Salfred * read returns 0 on EOF, no need to set error 68813675Sdyson */ 68976760Salfred if (rpipe->pipe_state & PIPE_EOF) 69013675Sdyson break; 69143623Sdillon 69213675Sdyson /* 69313675Sdyson * If the "write-side" has been blocked, wake it up now. 69413675Sdyson */ 69513675Sdyson if (rpipe->pipe_state & PIPE_WANTW) { 69613675Sdyson rpipe->pipe_state &= ~PIPE_WANTW; 69713675Sdyson wakeup(rpipe); 69813675Sdyson } 69943623Sdillon 70043623Sdillon /* 70147748Salc * Break if some data was read. 70243623Sdillon */ 70347748Salc if (nread > 0) 70413675Sdyson break; 70516960Sdyson 70643623Sdillon /* 707124394Sdes * Unlock the pipe buffer for our remaining processing. 708116127Smux * We will either break out with an error or we will 709116127Smux * sleep and relock to loop. 71043623Sdillon */ 71147748Salc pipeunlock(rpipe); 71243623Sdillon 71313675Sdyson /* 71447748Salc * Handle non-blocking mode operation or 71547748Salc * wait for more data. 71613675Sdyson */ 71776760Salfred if (fp->f_flag & FNONBLOCK) { 71847748Salc error = EAGAIN; 71976760Salfred } else { 72047748Salc rpipe->pipe_state |= PIPE_WANTR; 72191362Salfred if ((error = msleep(rpipe, PIPE_MTX(rpipe), 72291362Salfred PRIBIO | PCATCH, 72377140Salfred "piperd", 0)) == 0) 72447748Salc error = pipelock(rpipe, 1); 72513675Sdyson } 72647748Salc if (error) 72747748Salc goto unlocked_error; 72813675Sdyson } 72913675Sdyson } 730101768Srwatson#ifdef MAC 731101768Srwatsonlocked_error: 732101768Srwatson#endif 73347748Salc pipeunlock(rpipe); 73413675Sdyson 73591362Salfred /* XXX: should probably do this before getting any locks. */ 73624101Sbde if (error == 0) 73755112Sbde vfs_timestamp(&rpipe->pipe_atime); 73847748Salcunlocked_error: 73947748Salc --rpipe->pipe_busy; 74013913Sdyson 74147748Salc /* 74247748Salc * PIPE_WANT processing only makes sense if pipe_busy is 0. 74347748Salc */ 74413675Sdyson if ((rpipe->pipe_busy == 0) && (rpipe->pipe_state & PIPE_WANT)) { 74513675Sdyson rpipe->pipe_state &= ~(PIPE_WANT|PIPE_WANTW); 74613675Sdyson wakeup(rpipe); 74713675Sdyson } else if (rpipe->pipe_buffer.cnt < MINPIPESIZE) { 74813675Sdyson /* 74947748Salc * Handle write blocking hysteresis. 75013675Sdyson */ 75113675Sdyson if (rpipe->pipe_state & PIPE_WANTW) { 75213675Sdyson rpipe->pipe_state &= ~PIPE_WANTW; 75313675Sdyson wakeup(rpipe); 75413675Sdyson } 75513675Sdyson } 75614037Sdyson 75714802Sdyson if ((rpipe->pipe_buffer.size - rpipe->pipe_buffer.cnt) >= PIPE_BUF) 75814037Sdyson pipeselwakeup(rpipe); 75914037Sdyson 76091362Salfred PIPE_UNLOCK(rpipe); 76176760Salfred return (error); 76213675Sdyson} 76313675Sdyson 76414037Sdyson#ifndef PIPE_NODIRECT 76513907Sdyson/* 76613907Sdyson * Map the sending processes' buffer into kernel space and wire it. 76713907Sdyson * This is similar to a physical write operation. 76813907Sdyson */ 76913675Sdysonstatic int 77013907Sdysonpipe_build_write_buffer(wpipe, uio) 77113907Sdyson struct pipe *wpipe; 77213675Sdyson struct uio *uio; 77313675Sdyson{ 77418863Sdyson u_int size; 775216511Salc int i; 77613907Sdyson 77791412Salfred PIPE_LOCK_ASSERT(wpipe, MA_NOTOWNED); 778133790Ssilby KASSERT(wpipe->pipe_state & PIPE_DIRECTW, 779133790Ssilby ("Clone attempt on non-direct write pipe!")); 78079224Sdillon 781233353Skib if (uio->uio_iov->iov_len > wpipe->pipe_buffer.size) 782233353Skib size = wpipe->pipe_buffer.size; 783233353Skib else 784233353Skib size = uio->uio_iov->iov_len; 78513907Sdyson 786216699Salc if ((i = vm_fault_quick_hold_pages(&curproc->p_vmspace->vm_map, 787216699Salc (vm_offset_t)uio->uio_iov->iov_base, size, VM_PROT_READ, 788216699Salc wpipe->pipe_map.ms, PIPENPAGES)) < 0) 789193893Scperciva return (EFAULT); 79013907Sdyson 79113907Sdyson/* 79213907Sdyson * set up the control block 79313907Sdyson */ 79413907Sdyson wpipe->pipe_map.npages = i; 79576760Salfred wpipe->pipe_map.pos = 79676760Salfred ((vm_offset_t) uio->uio_iov->iov_base) & PAGE_MASK; 79713907Sdyson wpipe->pipe_map.cnt = size; 79813907Sdyson 79913907Sdyson/* 80013907Sdyson * and update the uio data 80113907Sdyson */ 80213907Sdyson 80313907Sdyson uio->uio_iov->iov_len -= size; 804104908Smike uio->uio_iov->iov_base = (char *)uio->uio_iov->iov_base + size; 80513907Sdyson if (uio->uio_iov->iov_len == 0) 80613907Sdyson uio->uio_iov++; 80713907Sdyson uio->uio_resid -= size; 80813907Sdyson uio->uio_offset += size; 80976760Salfred return (0); 81013907Sdyson} 81113907Sdyson 81213907Sdyson/* 81313907Sdyson * unmap and unwire the process buffer 81413907Sdyson */ 81513907Sdysonstatic void 81613907Sdysonpipe_destroy_write_buffer(wpipe) 81776760Salfred struct pipe *wpipe; 81813907Sdyson{ 81976364Salfred 820127501Salc PIPE_LOCK_ASSERT(wpipe, MA_OWNED); 821216511Salc vm_page_unhold_pages(wpipe->pipe_map.ms, wpipe->pipe_map.npages); 82291653Stanimura wpipe->pipe_map.npages = 0; 82313907Sdyson} 82413907Sdyson 82513907Sdyson/* 82613907Sdyson * In the case of a signal, the writing process might go away. This 82713907Sdyson * code copies the data into the circular buffer so that the source 82813907Sdyson * pages can be freed without loss of data. 82913907Sdyson */ 83013907Sdysonstatic void 83113907Sdysonpipe_clone_write_buffer(wpipe) 83276364Salfred struct pipe *wpipe; 83313907Sdyson{ 834127501Salc struct uio uio; 835127501Salc struct iovec iov; 83613907Sdyson int size; 83713907Sdyson int pos; 83813907Sdyson 83991362Salfred PIPE_LOCK_ASSERT(wpipe, MA_OWNED); 84013907Sdyson size = wpipe->pipe_map.cnt; 84113907Sdyson pos = wpipe->pipe_map.pos; 84213907Sdyson 84313907Sdyson wpipe->pipe_buffer.in = size; 84413907Sdyson wpipe->pipe_buffer.out = 0; 84513907Sdyson wpipe->pipe_buffer.cnt = size; 84613907Sdyson wpipe->pipe_state &= ~PIPE_DIRECTW; 84713907Sdyson 848119811Salc PIPE_UNLOCK(wpipe); 849127501Salc iov.iov_base = wpipe->pipe_buffer.buffer; 850127501Salc iov.iov_len = size; 851127501Salc uio.uio_iov = &iov; 852127501Salc uio.uio_iovcnt = 1; 853127501Salc uio.uio_offset = 0; 854127501Salc uio.uio_resid = size; 855127501Salc uio.uio_segflg = UIO_SYSSPACE; 856127501Salc uio.uio_rw = UIO_READ; 857127501Salc uio.uio_td = curthread; 858127501Salc uiomove_fromphys(wpipe->pipe_map.ms, pos, size, &uio); 859127501Salc PIPE_LOCK(wpipe); 86013907Sdyson pipe_destroy_write_buffer(wpipe); 86113907Sdyson} 86213907Sdyson 86313907Sdyson/* 86413907Sdyson * This implements the pipe buffer write mechanism. Note that only 86513907Sdyson * a direct write OR a normal pipe write can be pending at any given time. 86613907Sdyson * If there are any characters in the pipe buffer, the direct write will 86713907Sdyson * be deferred until the receiving process grabs all of the bytes from 86813907Sdyson * the pipe buffer. Then the direct mapping write is set-up. 86913907Sdyson */ 87013907Sdysonstatic int 87113907Sdysonpipe_direct_write(wpipe, uio) 87213907Sdyson struct pipe *wpipe; 87313907Sdyson struct uio *uio; 87413907Sdyson{ 87513907Sdyson int error; 87676364Salfred 87713951Sdysonretry: 87891362Salfred PIPE_LOCK_ASSERT(wpipe, MA_OWNED); 879133049Ssilby error = pipelock(wpipe, 1); 880133049Ssilby if (wpipe->pipe_state & PIPE_EOF) 881133049Ssilby error = EPIPE; 882133049Ssilby if (error) { 883133049Ssilby pipeunlock(wpipe); 884133049Ssilby goto error1; 885133049Ssilby } 88613907Sdyson while (wpipe->pipe_state & PIPE_DIRECTW) { 88776760Salfred if (wpipe->pipe_state & PIPE_WANTR) { 88813951Sdyson wpipe->pipe_state &= ~PIPE_WANTR; 88913951Sdyson wakeup(wpipe); 89013951Sdyson } 891173750Sdumbbell pipeselwakeup(wpipe); 89213992Sdyson wpipe->pipe_state |= PIPE_WANTW; 893133049Ssilby pipeunlock(wpipe); 89491362Salfred error = msleep(wpipe, PIPE_MTX(wpipe), 89591362Salfred PRIBIO | PCATCH, "pipdww", 0); 89614802Sdyson if (error) 89713907Sdyson goto error1; 898133049Ssilby else 899133049Ssilby goto retry; 90013907Sdyson } 90113907Sdyson wpipe->pipe_map.cnt = 0; /* transfer not ready yet */ 90213951Sdyson if (wpipe->pipe_buffer.cnt > 0) { 90376760Salfred if (wpipe->pipe_state & PIPE_WANTR) { 90413951Sdyson wpipe->pipe_state &= ~PIPE_WANTR; 90513951Sdyson wakeup(wpipe); 90613951Sdyson } 907173750Sdumbbell pipeselwakeup(wpipe); 90813992Sdyson wpipe->pipe_state |= PIPE_WANTW; 909133049Ssilby pipeunlock(wpipe); 91091362Salfred error = msleep(wpipe, PIPE_MTX(wpipe), 91191362Salfred PRIBIO | PCATCH, "pipdwc", 0); 91214802Sdyson if (error) 91313907Sdyson goto error1; 914133049Ssilby else 915133049Ssilby goto retry; 91613907Sdyson } 91713907Sdyson 91813951Sdyson wpipe->pipe_state |= PIPE_DIRECTW; 91913951Sdyson 920119872Salc PIPE_UNLOCK(wpipe); 92113907Sdyson error = pipe_build_write_buffer(wpipe, uio); 922119872Salc PIPE_LOCK(wpipe); 92313907Sdyson if (error) { 92413907Sdyson wpipe->pipe_state &= ~PIPE_DIRECTW; 925133049Ssilby pipeunlock(wpipe); 92613907Sdyson goto error1; 92713907Sdyson } 92813907Sdyson 92913907Sdyson error = 0; 93013907Sdyson while (!error && (wpipe->pipe_state & PIPE_DIRECTW)) { 93113907Sdyson if (wpipe->pipe_state & PIPE_EOF) { 93213907Sdyson pipe_destroy_write_buffer(wpipe); 933112981Shsu pipeselwakeup(wpipe); 93413907Sdyson pipeunlock(wpipe); 93514802Sdyson error = EPIPE; 93614802Sdyson goto error1; 93713907Sdyson } 93813992Sdyson if (wpipe->pipe_state & PIPE_WANTR) { 93913992Sdyson wpipe->pipe_state &= ~PIPE_WANTR; 94013992Sdyson wakeup(wpipe); 94113992Sdyson } 94214037Sdyson pipeselwakeup(wpipe); 943133049Ssilby pipeunlock(wpipe); 94491362Salfred error = msleep(wpipe, PIPE_MTX(wpipe), PRIBIO | PCATCH, 94591362Salfred "pipdwt", 0); 946133049Ssilby pipelock(wpipe, 0); 94713907Sdyson } 94813907Sdyson 949126131Sgreen if (wpipe->pipe_state & PIPE_EOF) 950126131Sgreen error = EPIPE; 95113907Sdyson if (wpipe->pipe_state & PIPE_DIRECTW) { 95213907Sdyson /* 95313907Sdyson * this bit of trickery substitutes a kernel buffer for 95413907Sdyson * the process that might be going away. 95513907Sdyson */ 95613907Sdyson pipe_clone_write_buffer(wpipe); 95713907Sdyson } else { 95813907Sdyson pipe_destroy_write_buffer(wpipe); 95913907Sdyson } 96013907Sdyson pipeunlock(wpipe); 96176760Salfred return (error); 96213907Sdyson 96313907Sdysonerror1: 96413907Sdyson wakeup(wpipe); 96576760Salfred return (error); 96613907Sdyson} 96714037Sdyson#endif 968124394Sdes 96916960Sdysonstatic int 970101941Srwatsonpipe_write(fp, uio, active_cred, flags, td) 97116960Sdyson struct file *fp; 97213907Sdyson struct uio *uio; 973101941Srwatson struct ucred *active_cred; 97483366Sjulian struct thread *td; 97545311Sdt int flags; 97613907Sdyson{ 97713675Sdyson int error = 0; 978233353Skib int desiredsize; 979233353Skib ssize_t orig_resid; 98016960Sdyson struct pipe *wpipe, *rpipe; 98116960Sdyson 982109153Sdillon rpipe = fp->f_data; 98316960Sdyson wpipe = rpipe->pipe_peer; 98416960Sdyson 98591395Salfred PIPE_LOCK(rpipe); 986133049Ssilby error = pipelock(wpipe, 1); 987133049Ssilby if (error) { 988133049Ssilby PIPE_UNLOCK(rpipe); 989133049Ssilby return (error); 990133049Ssilby } 99113675Sdyson /* 99213675Sdyson * detect loss of pipe read side, issue SIGPIPE if lost. 99313675Sdyson */ 994179243Skib if (wpipe->pipe_present != PIPE_ACTIVE || 995179243Skib (wpipe->pipe_state & PIPE_EOF)) { 996133049Ssilby pipeunlock(wpipe); 99791395Salfred PIPE_UNLOCK(rpipe); 99876760Salfred return (EPIPE); 99913675Sdyson } 1000101768Srwatson#ifdef MAC 1001172930Srwatson error = mac_pipe_check_write(active_cred, wpipe->pipe_pair); 1002101768Srwatson if (error) { 1003133049Ssilby pipeunlock(wpipe); 1004101768Srwatson PIPE_UNLOCK(rpipe); 1005101768Srwatson return (error); 1006101768Srwatson } 1007101768Srwatson#endif 100877676Sdillon ++wpipe->pipe_busy; 100913675Sdyson 1010133790Ssilby /* Choose a larger size if it's advantageous */ 1011133790Ssilby desiredsize = max(SMALL_PIPE_SIZE, wpipe->pipe_buffer.size); 1012133790Ssilby while (desiredsize < wpipe->pipe_buffer.cnt + uio->uio_resid) { 1013133790Ssilby if (piperesizeallowed != 1) 1014133790Ssilby break; 1015133790Ssilby if (amountpipekva > maxpipekva / 2) 1016133790Ssilby break; 1017133790Ssilby if (desiredsize == BIG_PIPE_SIZE) 1018133790Ssilby break; 1019133790Ssilby desiredsize = desiredsize * 2; 1020133790Ssilby } 102117163Sdyson 1022133790Ssilby /* Choose a smaller size if we're in a OOM situation */ 1023133790Ssilby if ((amountpipekva > (3 * maxpipekva) / 4) && 1024133790Ssilby (wpipe->pipe_buffer.size > SMALL_PIPE_SIZE) && 1025133790Ssilby (wpipe->pipe_buffer.cnt <= SMALL_PIPE_SIZE) && 1026133790Ssilby (piperesizeallowed == 1)) 1027133790Ssilby desiredsize = SMALL_PIPE_SIZE; 1028133790Ssilby 1029133790Ssilby /* Resize if the above determined that a new size was necessary */ 1030133790Ssilby if ((desiredsize != wpipe->pipe_buffer.size) && 1031133790Ssilby ((wpipe->pipe_state & PIPE_DIRECTW) == 0)) { 1032133049Ssilby PIPE_UNLOCK(wpipe); 1033133790Ssilby pipespace(wpipe, desiredsize); 1034133049Ssilby PIPE_LOCK(wpipe); 103513907Sdyson } 1036133790Ssilby if (wpipe->pipe_buffer.size == 0) { 1037133790Ssilby /* 1038133790Ssilby * This can only happen for reverse direction use of pipes 1039133790Ssilby * in a complete OOM situation. 1040133790Ssilby */ 1041133790Ssilby error = ENOMEM; 1042133790Ssilby --wpipe->pipe_busy; 1043133790Ssilby pipeunlock(wpipe); 1044133790Ssilby PIPE_UNLOCK(wpipe); 1045133790Ssilby return (error); 1046133790Ssilby } 104777676Sdillon 1048133049Ssilby pipeunlock(wpipe); 1049124394Sdes 105013913Sdyson orig_resid = uio->uio_resid; 105177676Sdillon 105213675Sdyson while (uio->uio_resid) { 105313907Sdyson int space; 105476760Salfred 1055133049Ssilby pipelock(wpipe, 0); 1056133049Ssilby if (wpipe->pipe_state & PIPE_EOF) { 1057133049Ssilby pipeunlock(wpipe); 1058133049Ssilby error = EPIPE; 1059133049Ssilby break; 1060133049Ssilby } 106114037Sdyson#ifndef PIPE_NODIRECT 106213907Sdyson /* 106313907Sdyson * If the transfer is large, we can gain performance if 106413907Sdyson * we do process-to-process copies directly. 106516416Sdyson * If the write is non-blocking, we don't use the 106616416Sdyson * direct write mechanism. 106758505Sdillon * 106858505Sdillon * The direct write mechanism will detect the reader going 106958505Sdillon * away on us. 107013907Sdyson */ 1071165347Spjd if (uio->uio_segflg == UIO_USERSPACE && 1072165347Spjd uio->uio_iov->iov_len >= PIPE_MINDIRECT && 1073165347Spjd wpipe->pipe_buffer.size >= PIPE_MINDIRECT && 1074127501Salc (fp->f_flag & FNONBLOCK) == 0) { 1075133049Ssilby pipeunlock(wpipe); 1076105009Salfred error = pipe_direct_write(wpipe, uio); 107776760Salfred if (error) 107813907Sdyson break; 107913907Sdyson continue; 108091362Salfred } 108114037Sdyson#endif 108213907Sdyson 108313907Sdyson /* 108413907Sdyson * Pipe buffered writes cannot be coincidental with 108513907Sdyson * direct writes. We wait until the currently executing 108613907Sdyson * direct write is completed before we start filling the 108758505Sdillon * pipe buffer. We break out if a signal occurs or the 108858505Sdillon * reader goes away. 108913907Sdyson */ 1090133049Ssilby if (wpipe->pipe_state & PIPE_DIRECTW) { 109113992Sdyson if (wpipe->pipe_state & PIPE_WANTR) { 109213992Sdyson wpipe->pipe_state &= ~PIPE_WANTR; 109313992Sdyson wakeup(wpipe); 109413992Sdyson } 1095173750Sdumbbell pipeselwakeup(wpipe); 1096173750Sdumbbell wpipe->pipe_state |= PIPE_WANTW; 1097133049Ssilby pipeunlock(wpipe); 109891395Salfred error = msleep(wpipe, PIPE_MTX(rpipe), PRIBIO | PCATCH, 109991362Salfred "pipbww", 0); 110013907Sdyson if (error) 110113907Sdyson break; 1102133049Ssilby else 1103133049Ssilby continue; 110413907Sdyson } 110513907Sdyson 110613907Sdyson space = wpipe->pipe_buffer.size - wpipe->pipe_buffer.cnt; 110714644Sdyson 110814644Sdyson /* Writes of size <= PIPE_BUF must be atomic. */ 110913913Sdyson if ((space < uio->uio_resid) && (orig_resid <= PIPE_BUF)) 111013913Sdyson space = 0; 111113907Sdyson 1112118230Spb if (space > 0) { 1113133049Ssilby int size; /* Transfer size */ 1114133049Ssilby int segsize; /* first segment to transfer */ 111576760Salfred 1116133049Ssilby /* 1117133049Ssilby * Transfer size is minimum of uio transfer 1118133049Ssilby * and free space in pipe buffer. 1119133049Ssilby */ 1120133049Ssilby if (space > uio->uio_resid) 1121133049Ssilby size = uio->uio_resid; 1122133049Ssilby else 1123133049Ssilby size = space; 1124133049Ssilby /* 1125133049Ssilby * First segment to transfer is minimum of 1126133049Ssilby * transfer size and contiguous space in 1127133049Ssilby * pipe buffer. If first segment to transfer 1128133049Ssilby * is less than the transfer size, we've got 1129133049Ssilby * a wraparound in the buffer. 1130133049Ssilby */ 1131133049Ssilby segsize = wpipe->pipe_buffer.size - 1132133049Ssilby wpipe->pipe_buffer.in; 1133133049Ssilby if (segsize > size) 1134133049Ssilby segsize = size; 113554534Stegge 1136133049Ssilby /* Transfer first segment */ 1137133049Ssilby 1138133049Ssilby PIPE_UNLOCK(rpipe); 1139133049Ssilby error = uiomove(&wpipe->pipe_buffer.buffer[wpipe->pipe_buffer.in], 1140133049Ssilby segsize, uio); 1141133049Ssilby PIPE_LOCK(rpipe); 1142133049Ssilby 1143133049Ssilby if (error == 0 && segsize < size) { 1144133049Ssilby KASSERT(wpipe->pipe_buffer.in + segsize == 1145133049Ssilby wpipe->pipe_buffer.size, 1146133049Ssilby ("Pipe buffer wraparound disappeared")); 114754534Stegge /* 1148133049Ssilby * Transfer remaining part now, to 1149133049Ssilby * support atomic writes. Wraparound 1150133049Ssilby * happened. 115154534Stegge */ 1152124394Sdes 115391395Salfred PIPE_UNLOCK(rpipe); 1154133049Ssilby error = uiomove( 1155133049Ssilby &wpipe->pipe_buffer.buffer[0], 1156133049Ssilby size - segsize, uio); 115791395Salfred PIPE_LOCK(rpipe); 1158133049Ssilby } 1159133049Ssilby if (error == 0) { 1160133049Ssilby wpipe->pipe_buffer.in += size; 1161133049Ssilby if (wpipe->pipe_buffer.in >= 1162133049Ssilby wpipe->pipe_buffer.size) { 1163133049Ssilby KASSERT(wpipe->pipe_buffer.in == 1164133049Ssilby size - segsize + 1165133049Ssilby wpipe->pipe_buffer.size, 1166133049Ssilby ("Expected wraparound bad")); 1167133049Ssilby wpipe->pipe_buffer.in = size - segsize; 116854534Stegge } 1169124394Sdes 1170133049Ssilby wpipe->pipe_buffer.cnt += size; 1171133049Ssilby KASSERT(wpipe->pipe_buffer.cnt <= 1172133049Ssilby wpipe->pipe_buffer.size, 1173133049Ssilby ("Pipe buffer overflow")); 117413675Sdyson } 1175133049Ssilby pipeunlock(wpipe); 1176153484Sdelphij if (error != 0) 1177153484Sdelphij break; 117813675Sdyson } else { 117913675Sdyson /* 118013675Sdyson * If the "read-side" has been blocked, wake it up now. 118113675Sdyson */ 118213675Sdyson if (wpipe->pipe_state & PIPE_WANTR) { 118313675Sdyson wpipe->pipe_state &= ~PIPE_WANTR; 118413675Sdyson wakeup(wpipe); 118513675Sdyson } 118614037Sdyson 118713675Sdyson /* 118813675Sdyson * don't block on non-blocking I/O 118913675Sdyson */ 119016960Sdyson if (fp->f_flag & FNONBLOCK) { 119113907Sdyson error = EAGAIN; 1192133049Ssilby pipeunlock(wpipe); 119313675Sdyson break; 119413675Sdyson } 119513907Sdyson 119614037Sdyson /* 119714037Sdyson * We have no more space and have something to offer, 119829356Speter * wake up select/poll. 119914037Sdyson */ 120014037Sdyson pipeselwakeup(wpipe); 120114037Sdyson 120213675Sdyson wpipe->pipe_state |= PIPE_WANTW; 1203133049Ssilby pipeunlock(wpipe); 120491395Salfred error = msleep(wpipe, PIPE_MTX(rpipe), 120591362Salfred PRIBIO | PCATCH, "pipewr", 0); 120676760Salfred if (error != 0) 120713675Sdyson break; 120813675Sdyson } 120913675Sdyson } 121013675Sdyson 1211133049Ssilby pipelock(wpipe, 0); 121214644Sdyson --wpipe->pipe_busy; 121377676Sdillon 121476760Salfred if ((wpipe->pipe_busy == 0) && (wpipe->pipe_state & PIPE_WANT)) { 121576760Salfred wpipe->pipe_state &= ~(PIPE_WANT | PIPE_WANTR); 121613675Sdyson wakeup(wpipe); 121713675Sdyson } else if (wpipe->pipe_buffer.cnt > 0) { 121813675Sdyson /* 121913675Sdyson * If we have put any characters in the buffer, we wake up 122013675Sdyson * the reader. 122113675Sdyson */ 122213675Sdyson if (wpipe->pipe_state & PIPE_WANTR) { 122313675Sdyson wpipe->pipe_state &= ~PIPE_WANTR; 122413675Sdyson wakeup(wpipe); 122513675Sdyson } 122613675Sdyson } 122713909Sdyson 122813909Sdyson /* 122913909Sdyson * Don't return EPIPE if I/O was successful 123013909Sdyson */ 123113907Sdyson if ((wpipe->pipe_buffer.cnt == 0) && 123277676Sdillon (uio->uio_resid == 0) && 123377676Sdillon (error == EPIPE)) { 123413907Sdyson error = 0; 123577676Sdillon } 123613913Sdyson 123724101Sbde if (error == 0) 123855112Sbde vfs_timestamp(&wpipe->pipe_mtime); 123924101Sbde 124014037Sdyson /* 124114037Sdyson * We have something to offer, 124229356Speter * wake up select/poll. 124314037Sdyson */ 124414177Sdyson if (wpipe->pipe_buffer.cnt) 124514037Sdyson pipeselwakeup(wpipe); 124613907Sdyson 1247133049Ssilby pipeunlock(wpipe); 124891395Salfred PIPE_UNLOCK(rpipe); 124976760Salfred return (error); 125013675Sdyson} 125113675Sdyson 1252175140Sjhb/* ARGSUSED */ 1253175140Sjhbstatic int 1254175140Sjhbpipe_truncate(fp, length, active_cred, td) 1255175140Sjhb struct file *fp; 1256175140Sjhb off_t length; 1257175140Sjhb struct ucred *active_cred; 1258175140Sjhb struct thread *td; 1259175140Sjhb{ 1260175140Sjhb 1261175140Sjhb return (EINVAL); 1262175140Sjhb} 1263175140Sjhb 126413675Sdyson/* 126513675Sdyson * we implement a very minimal set of ioctls for compatibility with sockets. 126613675Sdyson */ 1267104094Sphkstatic int 1268102003Srwatsonpipe_ioctl(fp, cmd, data, active_cred, td) 126913675Sdyson struct file *fp; 127036735Sdfr u_long cmd; 127199009Salfred void *data; 1272102003Srwatson struct ucred *active_cred; 127383366Sjulian struct thread *td; 127413675Sdyson{ 1275109153Sdillon struct pipe *mpipe = fp->f_data; 1276101768Srwatson int error; 127713675Sdyson 1278104269Srwatson PIPE_LOCK(mpipe); 1279104269Srwatson 1280104269Srwatson#ifdef MAC 1281172930Srwatson error = mac_pipe_check_ioctl(active_cred, mpipe->pipe_pair, cmd, data); 1282121970Srwatson if (error) { 1283121970Srwatson PIPE_UNLOCK(mpipe); 1284101768Srwatson return (error); 1285121970Srwatson } 1286101768Srwatson#endif 1287101768Srwatson 1288137752Sphk error = 0; 128913675Sdyson switch (cmd) { 129013675Sdyson 129113675Sdyson case FIONBIO: 1292137752Sphk break; 129313675Sdyson 129413675Sdyson case FIOASYNC: 129513675Sdyson if (*(int *)data) { 129613675Sdyson mpipe->pipe_state |= PIPE_ASYNC; 129713675Sdyson } else { 129813675Sdyson mpipe->pipe_state &= ~PIPE_ASYNC; 129913675Sdyson } 1300137752Sphk break; 130113675Sdyson 130213675Sdyson case FIONREAD: 130314037Sdyson if (mpipe->pipe_state & PIPE_DIRECTW) 130414037Sdyson *(int *)data = mpipe->pipe_map.cnt; 130514037Sdyson else 130614037Sdyson *(int *)data = mpipe->pipe_buffer.cnt; 1307137752Sphk break; 130813675Sdyson 130941086Struckman case FIOSETOWN: 1310138032Srwatson PIPE_UNLOCK(mpipe); 1311137752Sphk error = fsetown(*(int *)data, &mpipe->pipe_sigio); 1312138032Srwatson goto out_unlocked; 131341086Struckman 131441086Struckman case FIOGETOWN: 1315104393Struckman *(int *)data = fgetown(&mpipe->pipe_sigio); 1316137752Sphk break; 131713675Sdyson 131841086Struckman /* This is deprecated, FIOSETOWN should be used instead. */ 131941086Struckman case TIOCSPGRP: 1320138032Srwatson PIPE_UNLOCK(mpipe); 1321137752Sphk error = fsetown(-(*(int *)data), &mpipe->pipe_sigio); 1322138032Srwatson goto out_unlocked; 132341086Struckman 132441086Struckman /* This is deprecated, FIOGETOWN should be used instead. */ 132518863Sdyson case TIOCGPGRP: 1326104393Struckman *(int *)data = -fgetown(&mpipe->pipe_sigio); 1327137752Sphk break; 132813675Sdyson 1329137752Sphk default: 1330137752Sphk error = ENOTTY; 1331137764Sphk break; 133213675Sdyson } 1333104269Srwatson PIPE_UNLOCK(mpipe); 1334138032Srwatsonout_unlocked: 1335137752Sphk return (error); 133613675Sdyson} 133713675Sdyson 1338104094Sphkstatic int 1339101983Srwatsonpipe_poll(fp, events, active_cred, td) 134013675Sdyson struct file *fp; 134129356Speter int events; 1342101983Srwatson struct ucred *active_cred; 134383366Sjulian struct thread *td; 134413675Sdyson{ 1345109153Sdillon struct pipe *rpipe = fp->f_data; 134613675Sdyson struct pipe *wpipe; 134729356Speter int revents = 0; 1348101768Srwatson#ifdef MAC 1349101768Srwatson int error; 1350101768Srwatson#endif 135113675Sdyson 135213675Sdyson wpipe = rpipe->pipe_peer; 135391362Salfred PIPE_LOCK(rpipe); 1354101768Srwatson#ifdef MAC 1355172930Srwatson error = mac_pipe_check_poll(active_cred, rpipe->pipe_pair); 1356101768Srwatson if (error) 1357101768Srwatson goto locked_error; 1358101768Srwatson#endif 135929356Speter if (events & (POLLIN | POLLRDNORM)) 136029356Speter if ((rpipe->pipe_state & PIPE_DIRECTW) || 1361195423Skib (rpipe->pipe_buffer.cnt > 0)) 136229356Speter revents |= events & (POLLIN | POLLRDNORM); 136313675Sdyson 136429356Speter if (events & (POLLOUT | POLLWRNORM)) 1365179243Skib if (wpipe->pipe_present != PIPE_ACTIVE || 1366179243Skib (wpipe->pipe_state & PIPE_EOF) || 136743311Sdillon (((wpipe->pipe_state & PIPE_DIRECTW) == 0) && 1368230955Sjilles ((wpipe->pipe_buffer.size - wpipe->pipe_buffer.cnt) >= PIPE_BUF || 1369230955Sjilles wpipe->pipe_buffer.size == 0))) 137029356Speter revents |= events & (POLLOUT | POLLWRNORM); 137113675Sdyson 1372195423Skib if ((events & POLLINIGNEOF) == 0) { 1373195423Skib if (rpipe->pipe_state & PIPE_EOF) { 1374195423Skib revents |= (events & (POLLIN | POLLRDNORM)); 1375195423Skib if (wpipe->pipe_present != PIPE_ACTIVE || 1376195423Skib (wpipe->pipe_state & PIPE_EOF)) 1377195423Skib revents |= POLLHUP; 1378195423Skib } 1379195423Skib } 138029356Speter 138129356Speter if (revents == 0) { 138229356Speter if (events & (POLLIN | POLLRDNORM)) { 138383805Sjhb selrecord(td, &rpipe->pipe_sel); 1384174647Sjeff if (SEL_WAITING(&rpipe->pipe_sel)) 1385174647Sjeff rpipe->pipe_state |= PIPE_SEL; 138613675Sdyson } 138713675Sdyson 138829356Speter if (events & (POLLOUT | POLLWRNORM)) { 138983805Sjhb selrecord(td, &wpipe->pipe_sel); 1390174647Sjeff if (SEL_WAITING(&wpipe->pipe_sel)) 1391174647Sjeff wpipe->pipe_state |= PIPE_SEL; 139213907Sdyson } 139313675Sdyson } 1394101768Srwatson#ifdef MAC 1395101768Srwatsonlocked_error: 1396101768Srwatson#endif 139791362Salfred PIPE_UNLOCK(rpipe); 139829356Speter 139929356Speter return (revents); 140013675Sdyson} 140113675Sdyson 140298989Salfred/* 140398989Salfred * We shouldn't need locks here as we're doing a read and this should 140498989Salfred * be a natural race. 140598989Salfred */ 140652983Speterstatic int 1407101983Srwatsonpipe_stat(fp, ub, active_cred, td) 140852983Speter struct file *fp; 140952983Speter struct stat *ub; 1410101983Srwatson struct ucred *active_cred; 141183366Sjulian struct thread *td; 141213675Sdyson{ 1413229248Skib struct pipe *pipe; 1414229248Skib int new_unr; 1415101768Srwatson#ifdef MAC 1416101768Srwatson int error; 1417229248Skib#endif 141852983Speter 1419229248Skib pipe = fp->f_data; 1420104269Srwatson PIPE_LOCK(pipe); 1421229248Skib#ifdef MAC 1422172930Srwatson error = mac_pipe_check_stat(active_cred, pipe->pipe_pair); 1423229248Skib if (error) { 1424229248Skib PIPE_UNLOCK(pipe); 1425101768Srwatson return (error); 1426229248Skib } 1427101768Srwatson#endif 1428229248Skib /* 1429229248Skib * Lazily allocate an inode number for the pipe. Most pipe 1430229248Skib * users do not call fstat(2) on the pipe, which means that 1431229248Skib * postponing the inode allocation until it is must be 1432229248Skib * returned to userland is useful. If alloc_unr failed, 1433229248Skib * assign st_ino zero instead of returning an error. 1434229248Skib * Special pipe_ino values: 1435229248Skib * -1 - not yet initialized; 1436229248Skib * 0 - alloc_unr failed, return 0 as st_ino forever. 1437229248Skib */ 1438229248Skib if (pipe->pipe_ino == (ino_t)-1) { 1439229248Skib new_unr = alloc_unr(pipeino_unr); 1440229248Skib if (new_unr != -1) 1441229248Skib pipe->pipe_ino = new_unr; 1442229248Skib else 1443229248Skib pipe->pipe_ino = 0; 1444229248Skib } 1445229248Skib PIPE_UNLOCK(pipe); 1446229248Skib 1447100527Salfred bzero(ub, sizeof(*ub)); 144817124Sbde ub->st_mode = S_IFIFO; 1449133790Ssilby ub->st_blksize = PAGE_SIZE; 1450132436Ssilby if (pipe->pipe_state & PIPE_DIRECTW) 1451132436Ssilby ub->st_size = pipe->pipe_map.cnt; 1452132436Ssilby else 1453132436Ssilby ub->st_size = pipe->pipe_buffer.cnt; 145413675Sdyson ub->st_blocks = (ub->st_size + ub->st_blksize - 1) / ub->st_blksize; 1455205792Sed ub->st_atim = pipe->pipe_atime; 1456205792Sed ub->st_mtim = pipe->pipe_mtime; 1457205792Sed ub->st_ctim = pipe->pipe_ctime; 145860404Schris ub->st_uid = fp->f_cred->cr_uid; 145960404Schris ub->st_gid = fp->f_cred->cr_gid; 1460226578Skib ub->st_dev = pipedev_ino; 1461226578Skib ub->st_ino = pipe->pipe_ino; 146217124Sbde /* 1463226578Skib * Left as 0: st_nlink, st_rdev, st_flags, st_gen. 146417124Sbde */ 146576760Salfred return (0); 146613675Sdyson} 146713675Sdyson 146813675Sdyson/* ARGSUSED */ 146913675Sdysonstatic int 147083366Sjulianpipe_close(fp, td) 147113675Sdyson struct file *fp; 147283366Sjulian struct thread *td; 147313675Sdyson{ 1474109153Sdillon struct pipe *cpipe = fp->f_data; 147516322Sgpalmer 147649413Sgreen fp->f_ops = &badfileops; 1477109153Sdillon fp->f_data = NULL; 147896122Salfred funsetown(&cpipe->pipe_sigio); 147913675Sdyson pipeclose(cpipe); 148076760Salfred return (0); 148113675Sdyson} 148213675Sdyson 148376364Salfredstatic void 148476364Salfredpipe_free_kmem(cpipe) 148576364Salfred struct pipe *cpipe; 148676364Salfred{ 148791412Salfred 1488125293Srwatson KASSERT(!mtx_owned(PIPE_MTX(cpipe)), 1489125293Srwatson ("pipe_free_kmem: pipe mutex locked")); 149076364Salfred 149176364Salfred if (cpipe->pipe_buffer.buffer != NULL) { 1492189649Sjhb atomic_subtract_long(&amountpipekva, cpipe->pipe_buffer.size); 1493118764Ssilby vm_map_remove(pipe_map, 1494118764Ssilby (vm_offset_t)cpipe->pipe_buffer.buffer, 1495118764Ssilby (vm_offset_t)cpipe->pipe_buffer.buffer + cpipe->pipe_buffer.size); 149676364Salfred cpipe->pipe_buffer.buffer = NULL; 149776364Salfred } 149876364Salfred#ifndef PIPE_NODIRECT 1499127501Salc { 150076364Salfred cpipe->pipe_map.cnt = 0; 150176364Salfred cpipe->pipe_map.pos = 0; 150276364Salfred cpipe->pipe_map.npages = 0; 150376364Salfred } 150476364Salfred#endif 150576364Salfred} 150676364Salfred 150713675Sdyson/* 150813675Sdyson * shutdown the pipe 150913675Sdyson */ 151013675Sdysonstatic void 151113675Sdysonpipeclose(cpipe) 151213675Sdyson struct pipe *cpipe; 151313675Sdyson{ 1514125293Srwatson struct pipepair *pp; 151513907Sdyson struct pipe *ppipe; 1516226578Skib ino_t ino; 151776364Salfred 1518125293Srwatson KASSERT(cpipe != NULL, ("pipeclose: cpipe == NULL")); 151991968Salfred 1520125293Srwatson PIPE_LOCK(cpipe); 1521133049Ssilby pipelock(cpipe, 0); 1522125293Srwatson pp = cpipe->pipe_pair; 152391968Salfred 152491968Salfred pipeselwakeup(cpipe); 152513907Sdyson 152691968Salfred /* 152791968Salfred * If the other side is blocked, wake it up saying that 152891968Salfred * we want to close it down. 152991968Salfred */ 1530126131Sgreen cpipe->pipe_state |= PIPE_EOF; 153191968Salfred while (cpipe->pipe_busy) { 153291968Salfred wakeup(cpipe); 1533126131Sgreen cpipe->pipe_state |= PIPE_WANT; 1534133049Ssilby pipeunlock(cpipe); 153591968Salfred msleep(cpipe, PIPE_MTX(cpipe), PRIBIO, "pipecl", 0); 1536133049Ssilby pipelock(cpipe, 0); 153791968Salfred } 153813675Sdyson 1539101768Srwatson 154091968Salfred /* 1541125293Srwatson * Disconnect from peer, if any. 154291968Salfred */ 1543125293Srwatson ppipe = cpipe->pipe_peer; 1544179243Skib if (ppipe->pipe_present == PIPE_ACTIVE) { 154591968Salfred pipeselwakeup(ppipe); 154613907Sdyson 154791968Salfred ppipe->pipe_state |= PIPE_EOF; 154891968Salfred wakeup(ppipe); 1549133741Sjmg KNOTE_LOCKED(&ppipe->pipe_sel.si_note, 0); 155091968Salfred } 1551125293Srwatson 155291968Salfred /* 1553125293Srwatson * Mark this endpoint as free. Release kmem resources. We 1554125293Srwatson * don't mark this endpoint as unused until we've finished 1555125293Srwatson * doing that, or the pipe might disappear out from under 1556125293Srwatson * us. 155791968Salfred */ 1558125293Srwatson PIPE_UNLOCK(cpipe); 1559125293Srwatson pipe_free_kmem(cpipe); 1560125293Srwatson PIPE_LOCK(cpipe); 1561179243Skib cpipe->pipe_present = PIPE_CLOSING; 1562126131Sgreen pipeunlock(cpipe); 1563179243Skib 1564179243Skib /* 1565179243Skib * knlist_clear() may sleep dropping the PIPE_MTX. Set the 1566179243Skib * PIPE_FINALIZED, that allows other end to free the 1567179243Skib * pipe_pair, only after the knotes are completely dismantled. 1568179243Skib */ 1569133741Sjmg knlist_clear(&cpipe->pipe_sel.si_note, 1); 1570179243Skib cpipe->pipe_present = PIPE_FINALIZED; 1571225177Sattilio seldrain(&cpipe->pipe_sel); 1572133741Sjmg knlist_destroy(&cpipe->pipe_sel.si_note); 1573125293Srwatson 1574125293Srwatson /* 1575226578Skib * Postpone the destroy of the fake inode number allocated for 1576226578Skib * our end, until pipe mtx is unlocked. 1577226578Skib */ 1578226578Skib ino = cpipe->pipe_ino; 1579226578Skib 1580226578Skib /* 1581125293Srwatson * If both endpoints are now closed, release the memory for the 1582125293Srwatson * pipe pair. If not, unlock. 1583125293Srwatson */ 1584179243Skib if (ppipe->pipe_present == PIPE_FINALIZED) { 158591968Salfred PIPE_UNLOCK(cpipe); 1586125293Srwatson#ifdef MAC 1587172930Srwatson mac_pipe_destroy(pp); 1588125293Srwatson#endif 1589125293Srwatson uma_zfree(pipe_zone, cpipe->pipe_pair); 1590125293Srwatson } else 1591125293Srwatson PIPE_UNLOCK(cpipe); 1592226578Skib 1593229016Skib if (ino != 0 && ino != (ino_t)-1) 1594229016Skib free_unr(pipeino_unr, ino); 159513675Sdyson} 159659288Sjlemon 159772521Sjlemon/*ARGSUSED*/ 159859288Sjlemonstatic int 159972521Sjlemonpipe_kqfilter(struct file *fp, struct knote *kn) 160059288Sjlemon{ 160189306Salfred struct pipe *cpipe; 160259288Sjlemon 1603109153Sdillon cpipe = kn->kn_fp->f_data; 1604126131Sgreen PIPE_LOCK(cpipe); 160572521Sjlemon switch (kn->kn_filter) { 160672521Sjlemon case EVFILT_READ: 160772521Sjlemon kn->kn_fop = &pipe_rfiltops; 160872521Sjlemon break; 160972521Sjlemon case EVFILT_WRITE: 161072521Sjlemon kn->kn_fop = &pipe_wfiltops; 1611179243Skib if (cpipe->pipe_peer->pipe_present != PIPE_ACTIVE) { 1612101382Sdes /* other end of pipe has been closed */ 1613126131Sgreen PIPE_UNLOCK(cpipe); 1614118929Sjmg return (EPIPE); 1615126131Sgreen } 1616126131Sgreen cpipe = cpipe->pipe_peer; 161772521Sjlemon break; 161872521Sjlemon default: 1619126131Sgreen PIPE_UNLOCK(cpipe); 1620133741Sjmg return (EINVAL); 162172521Sjlemon } 162278292Sjlemon 1623133741Sjmg knlist_add(&cpipe->pipe_sel.si_note, kn, 1); 162491372Salfred PIPE_UNLOCK(cpipe); 162559288Sjlemon return (0); 162659288Sjlemon} 162759288Sjlemon 162859288Sjlemonstatic void 162959288Sjlemonfilt_pipedetach(struct knote *kn) 163059288Sjlemon{ 1631121018Sjmg struct pipe *cpipe = (struct pipe *)kn->kn_fp->f_data; 163259288Sjlemon 1633126131Sgreen PIPE_LOCK(cpipe); 1634179242Skib if (kn->kn_filter == EVFILT_WRITE) 1635121018Sjmg cpipe = cpipe->pipe_peer; 1636133741Sjmg knlist_remove(&cpipe->pipe_sel.si_note, kn, 1); 163791372Salfred PIPE_UNLOCK(cpipe); 163859288Sjlemon} 163959288Sjlemon 164059288Sjlemon/*ARGSUSED*/ 164159288Sjlemonstatic int 164259288Sjlemonfilt_piperead(struct knote *kn, long hint) 164359288Sjlemon{ 1644109153Sdillon struct pipe *rpipe = kn->kn_fp->f_data; 164559288Sjlemon struct pipe *wpipe = rpipe->pipe_peer; 1646133741Sjmg int ret; 164759288Sjlemon 164891372Salfred PIPE_LOCK(rpipe); 164959288Sjlemon kn->kn_data = rpipe->pipe_buffer.cnt; 165059288Sjlemon if ((kn->kn_data == 0) && (rpipe->pipe_state & PIPE_DIRECTW)) 165159288Sjlemon kn->kn_data = rpipe->pipe_map.cnt; 165259288Sjlemon 165359288Sjlemon if ((rpipe->pipe_state & PIPE_EOF) || 1654179243Skib wpipe->pipe_present != PIPE_ACTIVE || 1655179243Skib (wpipe->pipe_state & PIPE_EOF)) { 165691372Salfred kn->kn_flags |= EV_EOF; 165791372Salfred PIPE_UNLOCK(rpipe); 165859288Sjlemon return (1); 165959288Sjlemon } 1660133741Sjmg ret = kn->kn_data > 0; 166191372Salfred PIPE_UNLOCK(rpipe); 1662133741Sjmg return ret; 166359288Sjlemon} 166459288Sjlemon 166559288Sjlemon/*ARGSUSED*/ 166659288Sjlemonstatic int 166759288Sjlemonfilt_pipewrite(struct knote *kn, long hint) 166859288Sjlemon{ 1669109153Sdillon struct pipe *rpipe = kn->kn_fp->f_data; 167059288Sjlemon struct pipe *wpipe = rpipe->pipe_peer; 167159288Sjlemon 167291372Salfred PIPE_LOCK(rpipe); 1673179243Skib if (wpipe->pipe_present != PIPE_ACTIVE || 1674179243Skib (wpipe->pipe_state & PIPE_EOF)) { 167559288Sjlemon kn->kn_data = 0; 1676124394Sdes kn->kn_flags |= EV_EOF; 167791372Salfred PIPE_UNLOCK(rpipe); 167859288Sjlemon return (1); 167959288Sjlemon } 1680230955Sjilles kn->kn_data = (wpipe->pipe_buffer.size > 0) ? 1681230955Sjilles (wpipe->pipe_buffer.size - wpipe->pipe_buffer.cnt) : PIPE_BUF; 168265855Sjlemon if (wpipe->pipe_state & PIPE_DIRECTW) 168359288Sjlemon kn->kn_data = 0; 168459288Sjlemon 168591372Salfred PIPE_UNLOCK(rpipe); 168659288Sjlemon return (kn->kn_data >= PIPE_BUF); 168759288Sjlemon} 1688