/* $NetBSD: sys_pipe.c,v 1.32 2002/12/05 16:30:55 jdolecek Exp $ */ /* * Copyright (c) 1996 John S. Dyson * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice immediately at the beginning of the file, without modification, * this list of conditions, and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Absolutely no warranty of function or purpose is made by the author * John S. Dyson. * 4. Modifications may be freely made to this file if the above conditions * are met. * * $FreeBSD: src/sys/kern/sys_pipe.c,v 1.95 2002/03/09 22:06:31 alfred Exp $ */ /* * This file contains a high-performance replacement for the socket-based * pipes scheme originally used in FreeBSD/4.4Lite. It does not support * all features of sockets, but does do everything that pipes normally * do. * * Adaption for NetBSD UVM, including uvm_loan() based direct write, was * written by Jaromir Dolecek. */ /* * This code has two modes of operation, a small write mode and a large * write mode. The small write mode acts like conventional pipes with * a kernel buffer. If the buffer is less than PIPE_MINDIRECT, then the * "normal" pipe buffering is done. If the buffer is between PIPE_MINDIRECT * and PIPE_SIZE in size, it is fully mapped into the kernel (on FreeBSD, * those pages are also wired), and the receiving process can copy it directly * from the pages in the sending process. * * If the sending process receives a signal, it is possible that it will * go away, and certainly its address space can change, because control * is returned back to the user-mode side. In that case, the pipe code * arranges to copy the buffer supplied by the user process on FreeBSD, to * a pageable kernel buffer, and the receiving process will grab the data * from the pageable kernel buffer. Since signals don't happen all that often, * the copy operation is normally eliminated. * For NetBSD, the pages are mapped read-only, COW for kernel by uvm_loan(), * so no explicit handling need to be done, all is handled by standard VM * facilities. * * The constant PIPE_MINDIRECT is chosen to make sure that buffering will * happen for small transfers so that the system will not spend all of * its time context switching. PIPE_SIZE is constrained by the * amount of kernel virtual memory. */ #include __KERNEL_RCSID(0, "$NetBSD: sys_pipe.c,v 1.32 2002/12/05 16:30:55 jdolecek Exp $"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef __FreeBSD__ #include #endif #ifdef __NetBSD__ #include #include #include #include #include #include #endif /* NetBSD, FreeBSD */ #include #ifdef __NetBSD__ /* * Avoid microtime(9), it's slow. We don't guard the read from time(9) * with splclock(9) since we don't actually need to be THAT sure the access * is atomic. */ #define vfs_timestamp(tv) (*(tv) = time) /* we call it sel_klist */ #define sel_note sel_klist #endif /* * Use this define if you want to disable *fancy* VM things. Expect an * approx 30% decrease in transfer rate. This could be useful for * OpenBSD. */ /* #define PIPE_NODIRECT */ /* * interfaces to the outside world */ #ifdef __FreeBSD__ static int pipe_read(struct file *fp, struct uio *uio, struct ucred *cred, int flags, struct thread *td); static int pipe_write(struct file *fp, struct uio *uio, struct ucred *cred, int flags, struct thread *td); static int pipe_close(struct file *fp, struct thread *td); static int pipe_poll(struct file *fp, int events, struct ucred *cred, struct thread *td); static int pipe_kqfilter(struct file *fp, struct knote *kn); static int pipe_stat(struct file *fp, struct stat *sb, struct thread *td); static int pipe_ioctl(struct file *fp, u_long cmd, caddr_t data, struct thread *td); static struct fileops pipeops = { pipe_read, pipe_write, pipe_ioctl, pipe_poll, pipe_kqfilter, pipe_stat, pipe_close }; #define PIPE_GET_GIANT(pipe) \ do { \ PIPE_UNLOCK(wpipe); \ mtx_lock(&Giant); \ } while (/*CONSTCOND*/ 0) #define PIPE_DROP_GIANT(pipe) \ do { \ mtx_unlock(&Giant); \ PIPE_LOCK(wpipe); \ } while (/*CONSTCOND*/ 0) #endif /* FreeBSD */ #ifdef __NetBSD__ static int pipe_read(struct file *fp, off_t *offset, struct uio *uio, struct ucred *cred, int flags); static int pipe_write(struct file *fp, off_t *offset, struct uio *uio, struct ucred *cred, int flags); static int pipe_close(struct file *fp, struct proc *p); static int pipe_poll(struct file *fp, int events, struct proc *p); static int pipe_fcntl(struct file *fp, u_int com, caddr_t data, struct proc *p); static int pipe_kqfilter(struct file *fp, struct knote *kn); static int pipe_stat(struct file *fp, struct stat *sb, struct proc *p); static int pipe_ioctl(struct file *fp, u_long cmd, caddr_t data, struct proc *p); static struct fileops pipeops = { pipe_read, pipe_write, pipe_ioctl, pipe_fcntl, pipe_poll, pipe_stat, pipe_close, pipe_kqfilter }; /* XXXSMP perhaps use spinlocks & KERNEL_PROC_(UN)LOCK() ? just clear now */ #define PIPE_GET_GIANT(pipe) #define PIPE_DROP_GIANT(pipe) #define GIANT_REQUIRED #endif /* NetBSD */ /* * Default pipe buffer size(s), this can be kind-of large now because pipe * space is pageable. The pipe code will try to maintain locality of * reference for performance reasons, so small amounts of outstanding I/O * will not wipe the cache. */ #define MINPIPESIZE (PIPE_SIZE/3) #define MAXPIPESIZE (2*PIPE_SIZE/3) /* * Maximum amount of kva for pipes -- this is kind-of a soft limit, but * is there so that on large systems, we don't exhaust it. */ #define MAXPIPEKVA (8*1024*1024) static int maxpipekva = MAXPIPEKVA; /* * Limit for direct transfers, we cannot, of course limit * the amount of kva for pipes in general though. */ #define LIMITPIPEKVA (16*1024*1024) static int limitpipekva = LIMITPIPEKVA; /* * Limit the number of "big" pipes */ #define LIMITBIGPIPES 32 static int maxbigpipes = LIMITBIGPIPES; static int nbigpipe = 0; /* * Amount of KVA consumed by pipe buffers. */ static int amountpipekva = 0; static void pipeclose(struct pipe *cpipe); static void pipe_free_kmem(struct pipe *cpipe); static int pipe_create(struct pipe **cpipep, int allockva); static __inline int pipelock(struct pipe *cpipe, int catch); static __inline void pipeunlock(struct pipe *cpipe); static __inline void pipeselwakeup(struct pipe *cpipe, struct pipe *sigp); #ifndef PIPE_NODIRECT static int pipe_direct_write(struct pipe *wpipe, struct uio *uio); #endif static int pipespace(struct pipe *cpipe, int size); #ifdef __NetBSD__ #ifndef PIPE_NODIRECT static int pipe_loan_alloc(struct pipe *, int); static void pipe_loan_free(struct pipe *); #endif /* PIPE_NODIRECT */ static struct pool pipe_pool; #endif /* NetBSD */ #ifdef __FreeBSD__ static vm_zone_t pipe_zone; static void pipeinit(void *dummy __unused); #ifndef PIPE_NODIRECT static int pipe_build_write_buffer(struct pipe *wpipe, struct uio *uio); static void pipe_destroy_write_buffer(struct pipe *wpipe); static void pipe_clone_write_buffer(struct pipe *wpipe); #endif SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_ANY, pipeinit, NULL); static void pipeinit(void *dummy __unused) { pipe_zone = zinit("PIPE", sizeof(struct pipe), 0, 0, 4); } #endif /* FreeBSD */ /* * The pipe system call for the DTYPE_PIPE type of pipes */ /* ARGSUSED */ #ifdef __FreeBSD__ int pipe(td, uap) struct thread *td; struct pipe_args /* { int dummy; } */ *uap; #elif defined(__NetBSD__) int sys_pipe(p, v, retval) struct proc *p; void *v; register_t *retval; #endif { struct file *rf, *wf; struct pipe *rpipe, *wpipe; int fd, error; #ifdef __FreeBSD__ struct mtx *pmtx; KASSERT(pipe_zone != NULL, ("pipe_zone not initialized")); pmtx = malloc(sizeof(*pmtx), M_TEMP, M_WAITOK | M_ZERO); rpipe = wpipe = NULL; if (pipe_create(&rpipe, 1) || pipe_create(&wpipe, 1)) { pipeclose(rpipe); pipeclose(wpipe); free(pmtx, M_TEMP); return (ENFILE); } error = falloc(td, &rf, &fd); if (error) { pipeclose(rpipe); pipeclose(wpipe); free(pmtx, M_TEMP); return (error); } fhold(rf); td->td_retval[0] = fd; /* * Warning: once we've gotten past allocation of the fd for the * read-side, we can only drop the read side via fdrop() in order * to avoid races against processes which manage to dup() the read * side while we are blocked trying to allocate the write side. */ FILE_LOCK(rf); rf->f_flag = FREAD | FWRITE; rf->f_type = DTYPE_PIPE; rf->f_data = (caddr_t)rpipe; rf->f_ops = &pipeops; FILE_UNLOCK(rf); error = falloc(td, &wf, &fd); if (error) { struct filedesc *fdp = td->td_proc->p_fd; FILEDESC_LOCK(fdp); if (fdp->fd_ofiles[td->td_retval[0]] == rf) { fdp->fd_ofiles[td->td_retval[0]] = NULL; FILEDESC_UNLOCK(fdp); fdrop(rf, td); } else FILEDESC_UNLOCK(fdp); fdrop(rf, td); /* rpipe has been closed by fdrop(). */ pipeclose(wpipe); free(pmtx, M_TEMP); return (error); } FILE_LOCK(wf); wf->f_flag = FREAD | FWRITE; wf->f_type = DTYPE_PIPE; wf->f_data = (caddr_t)wpipe; wf->f_ops = &pipeops; p->p_retval[1] = fd; rpipe->pipe_peer = wpipe; wpipe->pipe_peer = rpipe; mtx_init(pmtx, "pipe mutex", MTX_DEF); rpipe->pipe_mtxp = wpipe->pipe_mtxp = pmtx; fdrop(rf, td); #endif /* FreeBSD */ #ifdef __NetBSD__ rpipe = wpipe = NULL; if (pipe_create(&rpipe, 1) || pipe_create(&wpipe, 0)) { pipeclose(rpipe); pipeclose(wpipe); return (ENFILE); } /* * Note: the file structure returned from falloc() is marked * as 'larval' initially. Unless we mark it as 'mature' by * FILE_SET_MATURE(), any attempt to do anything with it would * return EBADF, including e.g. dup(2) or close(2). This avoids * file descriptor races if we block in the second falloc(). */ error = falloc(p, &rf, &fd); if (error) goto free2; retval[0] = fd; rf->f_flag = FREAD; rf->f_type = DTYPE_PIPE; rf->f_data = (caddr_t)rpipe; rf->f_ops = &pipeops; error = falloc(p, &wf, &fd); if (error) goto free3; retval[1] = fd; wf->f_flag = FWRITE; wf->f_type = DTYPE_PIPE; wf->f_data = (caddr_t)wpipe; wf->f_ops = &pipeops; rpipe->pipe_peer = wpipe; wpipe->pipe_peer = rpipe; FILE_SET_MATURE(rf); FILE_SET_MATURE(wf); FILE_UNUSE(rf, p); FILE_UNUSE(wf, p); return (0); free3: FILE_UNUSE(rf, p); ffree(rf); fdremove(p->p_fd, retval[0]); free2: pipeclose(wpipe); pipeclose(rpipe); #endif /* NetBSD */ return (error); } /* * Allocate kva for pipe circular buffer, the space is pageable * This routine will 'realloc' the size of a pipe safely, if it fails * it will retain the old buffer. * If it fails it will return ENOMEM. */ static int pipespace(cpipe, size) struct pipe *cpipe; int size; { caddr_t buffer; #ifdef __FreeBSD__ struct vm_object *object; int npages, error; GIANT_REQUIRED; KASSERT(cpipe->pipe_mtxp == NULL || !mtx_owned(PIPE_MTX(cpipe)), ("pipespace: pipe mutex locked")); npages = round_page(size)/PAGE_SIZE; /* * Create an object, I don't like the idea of paging to/from * kernel_object. */ object = vm_object_allocate(OBJT_DEFAULT, npages); buffer = (caddr_t) vm_map_min(kernel_map); /* * Insert the object into the kernel map, and allocate kva for it. * The map entry is, by default, pageable. */ error = vm_map_find(kernel_map, object, 0, (vm_offset_t *) &buffer, size, 1, VM_PROT_ALL, VM_PROT_ALL, 0); if (error != KERN_SUCCESS) { vm_object_deallocate(object); return (ENOMEM); } #endif /* FreeBSD */ #ifdef __NetBSD__ /* * Allocate pageable virtual address space. Physical memory is allocated * on demand. */ buffer = (caddr_t) uvm_km_valloc(kernel_map, round_page(size)); if (buffer == NULL) return (ENOMEM); #endif /* NetBSD */ /* free old resources if we're resizing */ pipe_free_kmem(cpipe); #ifdef __FreeBSD__ cpipe->pipe_buffer.object = object; #endif cpipe->pipe_buffer.buffer = buffer; cpipe->pipe_buffer.size = size; cpipe->pipe_buffer.in = 0; cpipe->pipe_buffer.out = 0; cpipe->pipe_buffer.cnt = 0; amountpipekva += cpipe->pipe_buffer.size; return (0); } /* * initialize and allocate VM and memory for pipe */ static int pipe_create(cpipep, allockva) struct pipe **cpipep; int allockva; { struct pipe *cpipe; int error; #ifdef __FreeBSD__ *cpipep = zalloc(pipe_zone); #endif #ifdef __NetBSD__ *cpipep = pool_get(&pipe_pool, M_WAITOK); #endif if (*cpipep == NULL) return (ENOMEM); cpipe = *cpipep; /* Initialize */ memset(cpipe, 0, sizeof(*cpipe)); cpipe->pipe_state = PIPE_SIGNALR; #ifdef __FreeBSD__ cpipe->pipe_mtxp = NULL; /* avoid pipespace assertion */ #endif if (allockva && (error = pipespace(cpipe, PIPE_SIZE))) return (error); vfs_timestamp(&cpipe->pipe_ctime); cpipe->pipe_atime = cpipe->pipe_ctime; cpipe->pipe_mtime = cpipe->pipe_ctime; #ifdef __NetBSD__ cpipe->pipe_pgid = NO_PID; lockinit(&cpipe->pipe_lock, PRIBIO | PCATCH, "pipelk", 0, 0); #endif return (0); } /* * lock a pipe for I/O, blocking other access */ static __inline int pipelock(cpipe, catch) struct pipe *cpipe; int catch; { int error; #ifdef __FreeBSD__ PIPE_LOCK_ASSERT(cpipe, MA_OWNED); while (cpipe->pipe_state & PIPE_LOCKFL) { cpipe->pipe_state |= PIPE_LWANT; error = msleep(cpipe, PIPE_MTX(cpipe), catch ? (PRIBIO | PCATCH) : PRIBIO, "pipelk", 0); if (error != 0) return (error); } cpipe->pipe_state |= PIPE_LOCKFL; return (0); #endif #ifdef __NetBSD__ do { error = lockmgr(&cpipe->pipe_lock, LK_EXCLUSIVE, NULL); } while (!catch && (error == EINTR || error == ERESTART)); return (error); #endif } /* * unlock a pipe I/O lock */ static __inline void pipeunlock(cpipe) struct pipe *cpipe; { #ifdef __FreeBSD__ PIPE_LOCK_ASSERT(cpipe, MA_OWNED); cpipe->pipe_state &= ~PIPE_LOCKFL; if (cpipe->pipe_state & PIPE_LWANT) { cpipe->pipe_state &= ~PIPE_LWANT; wakeup(cpipe); } #endif #ifdef __NetBSD__ lockmgr(&cpipe->pipe_lock, LK_RELEASE, NULL); #endif } /* * Select/poll wakup. This also sends SIGIO to peer connected to * 'sigpipe' side of pipe. */ static __inline void pipeselwakeup(selp, sigp) struct pipe *selp, *sigp; { #ifdef __FreeBSD__ if (selp->pipe_state & PIPE_SEL) { selp->pipe_state &= ~PIPE_SEL; selwakeup(&selp->pipe_sel); } if (sigp && (sigp->pipe_state & PIPE_ASYNC) && sigp->pipe_sigio) pgsigio(sigp->pipe_sigio, SIGIO, 0); KNOTE(&selp->pipe_sel.sel_note, 0); #endif #ifdef __NetBSD__ selnotify(&selp->pipe_sel, 0); if (sigp && (sigp->pipe_state & PIPE_ASYNC) && sigp->pipe_pgid != NO_PID) { struct proc *p; if (sigp->pipe_pgid < 0) gsignal(-sigp->pipe_pgid, SIGIO); else if (sigp->pipe_pgid > 0 && (p = pfind(sigp->pipe_pgid)) != 0) psignal(p, SIGIO); } #endif /* NetBSD */ } /* ARGSUSED */ #ifdef __FreeBSD__ static int pipe_read(fp, uio, cred, flags, td) struct file *fp; struct uio *uio; struct ucred *cred; struct thread *td; int flags; struct proc *p; #elif defined(__NetBSD__) static int pipe_read(fp, offset, uio, cred, flags) struct file *fp; off_t *offset; struct uio *uio; struct ucred *cred; int flags; #endif { struct pipe *rpipe = (struct pipe *) fp->f_data; int error; size_t nread = 0; size_t size; size_t ocnt; PIPE_LOCK(rpipe); ++rpipe->pipe_busy; ocnt = rpipe->pipe_buffer.cnt; error = pipelock(rpipe, 1); if (error) goto unlocked_error; while (uio->uio_resid) { /* * normal pipe buffer receive */ if (rpipe->pipe_buffer.cnt > 0) { size = rpipe->pipe_buffer.size - rpipe->pipe_buffer.out; if (size > rpipe->pipe_buffer.cnt) size = rpipe->pipe_buffer.cnt; if (size > uio->uio_resid) size = uio->uio_resid; PIPE_UNLOCK(rpipe); error = uiomove(&rpipe->pipe_buffer.buffer[rpipe->pipe_buffer.out], size, uio); PIPE_LOCK(rpipe); if (error) break; rpipe->pipe_buffer.out += size; if (rpipe->pipe_buffer.out >= rpipe->pipe_buffer.size) rpipe->pipe_buffer.out = 0; rpipe->pipe_buffer.cnt -= size; /* * If there is no more to read in the pipe, reset * its pointers to the beginning. This improves * cache hit stats. */ if (rpipe->pipe_buffer.cnt == 0) { rpipe->pipe_buffer.in = 0; rpipe->pipe_buffer.out = 0; } nread += size; #ifndef PIPE_NODIRECT /* * Direct copy, bypassing a kernel buffer. */ } else if ((size = rpipe->pipe_map.cnt) && (rpipe->pipe_state & PIPE_DIRECTW)) { caddr_t va; if (size > uio->uio_resid) size = uio->uio_resid; va = (caddr_t) rpipe->pipe_map.kva + rpipe->pipe_map.pos; PIPE_UNLOCK(rpipe); error = uiomove(va, size, uio); PIPE_LOCK(rpipe); if (error) break; nread += size; rpipe->pipe_map.pos += size; rpipe->pipe_map.cnt -= size; if (rpipe->pipe_map.cnt == 0) { rpipe->pipe_state &= ~PIPE_DIRECTW; wakeup(rpipe); } #endif } else { /* * detect EOF condition * read returns 0 on EOF, no need to set error */ if (rpipe->pipe_state & PIPE_EOF) break; /* * If the "write-side" has been blocked, wake it up now. */ if (rpipe->pipe_state & PIPE_WANTW) { rpipe->pipe_state &= ~PIPE_WANTW; wakeup(rpipe); } /* * Break if some data was read. */ if (nread > 0) break; /* * don't block on non-blocking I/O */ if (fp->f_flag & FNONBLOCK) { error = EAGAIN; break; } /* * Unlock the pipe buffer for our remaining processing. * We will either break out with an error or we will * sleep and relock to loop. */ pipeunlock(rpipe); /* * We want to read more, wake up select/poll. */ pipeselwakeup(rpipe, rpipe->pipe_peer); rpipe->pipe_state |= PIPE_WANTR; #ifdef __FreeBSD__ error = msleep(rpipe, PIPE_MTX(rpipe), PRIBIO | PCATCH, "piperd", 0); #else error = tsleep(rpipe, PRIBIO | PCATCH, "piperd", 0); #endif if (error != 0 || (error = pipelock(rpipe, 1))) goto unlocked_error; } } pipeunlock(rpipe); /* XXX: should probably do this before getting any locks. */ if (error == 0) vfs_timestamp(&rpipe->pipe_atime); unlocked_error: --rpipe->pipe_busy; /* * PIPE_WANTCLOSE processing only makes sense if pipe_busy is 0. */ if ((rpipe->pipe_busy == 0) && (rpipe->pipe_state & PIPE_WANTCLOSE)) { rpipe->pipe_state &= ~(PIPE_WANTCLOSE|PIPE_WANTW); wakeup(rpipe); } else if (rpipe->pipe_buffer.cnt < MINPIPESIZE) { /* * Handle write blocking hysteresis. */ if (rpipe->pipe_state & PIPE_WANTW) { rpipe->pipe_state &= ~PIPE_WANTW; wakeup(rpipe); } } /* * If anything was read off the buffer, signal to the writer it's * possible to write more data. Also send signal if we are here for the * first time after last write. */ if ((rpipe->pipe_buffer.size - rpipe->pipe_buffer.cnt) >= PIPE_BUF && (ocnt != rpipe->pipe_buffer.cnt || (rpipe->pipe_state & PIPE_SIGNALR))) { pipeselwakeup(rpipe, rpipe->pipe_peer); rpipe->pipe_state &= ~PIPE_SIGNALR; } PIPE_UNLOCK(rpipe); return (error); } #ifdef __FreeBSD__ #ifndef PIPE_NODIRECT /* * Map the sending processes' buffer into kernel space and wire it. * This is similar to a physical write operation. */ static int pipe_build_write_buffer(wpipe, uio) struct pipe *wpipe; struct uio *uio; { size_t size; int i; vm_offset_t addr, endaddr, paddr; GIANT_REQUIRED; PIPE_LOCK_ASSERT(wpipe, MA_NOTOWNED); size = uio->uio_iov->iov_len; if (size > wpipe->pipe_buffer.size) size = wpipe->pipe_buffer.size; endaddr = round_page((vm_offset_t)uio->uio_iov->iov_base + size); addr = trunc_page((vm_offset_t)uio->uio_iov->iov_base); for (i = 0; addr < endaddr; addr += PAGE_SIZE, i++) { vm_page_t m; if (vm_fault_quick((caddr_t)addr, VM_PROT_READ) < 0 || (paddr = pmap_kextract(addr)) == 0) { int j; for (j = 0; j < i; j++) vm_page_unwire(wpipe->pipe_map.ms[j], 1); return (EFAULT); } m = PHYS_TO_VM_PAGE(paddr); vm_page_wire(m); wpipe->pipe_map.ms[i] = m; } /* * set up the control block */ wpipe->pipe_map.npages = i; wpipe->pipe_map.pos = ((vm_offset_t) uio->uio_iov->iov_base) & PAGE_MASK; wpipe->pipe_map.cnt = size; /* * and map the buffer */ if (wpipe->pipe_map.kva == 0) { /* * We need to allocate space for an extra page because the * address range might (will) span pages at times. */ wpipe->pipe_map.kva = kmem_alloc_pageable(kernel_map, wpipe->pipe_buffer.size + PAGE_SIZE); amountpipekva += wpipe->pipe_buffer.size + PAGE_SIZE; } pmap_qenter(wpipe->pipe_map.kva, wpipe->pipe_map.ms, wpipe->pipe_map.npages); /* * and update the uio data */ uio->uio_iov->iov_len -= size; uio->uio_iov->iov_base += size; if (uio->uio_iov->iov_len == 0) uio->uio_iov++; uio->uio_resid -= size; uio->uio_offset += size; return (0); } /* * unmap and unwire the process buffer */ static void pipe_destroy_write_buffer(wpipe) struct pipe *wpipe; { int i; GIANT_REQUIRED; PIPE_LOCK_ASSERT(wpipe, MA_NOTOWNED); if (wpipe->pipe_map.kva) { pmap_qremove(wpipe->pipe_map.kva, wpipe->pipe_map.npages); if (amountpipekva > maxpipekva) { vm_offset_t kva = wpipe->pipe_map.kva; wpipe->pipe_map.kva = 0; kmem_free(kernel_map, kva, wpipe->pipe_buffer.size + PAGE_SIZE); amountpipekva -= wpipe->pipe_buffer.size + PAGE_SIZE; } } for (i = 0; i < wpipe->pipe_map.npages; i++) vm_page_unwire(wpipe->pipe_map.ms[i], 1); wpipe->pipe_map.npages = 0; } /* * In the case of a signal, the writing process might go away. This * code copies the data into the circular buffer so that the source * pages can be freed without loss of data. */ static void pipe_clone_write_buffer(wpipe) struct pipe *wpipe; { int size; int pos; PIPE_LOCK_ASSERT(wpipe, MA_OWNED); size = wpipe->pipe_map.cnt; pos = wpipe->pipe_map.pos; memcpy((caddr_t) wpipe->pipe_buffer.buffer, (caddr_t) wpipe->pipe_map.kva + pos, size); wpipe->pipe_buffer.in = size; wpipe->pipe_buffer.out = 0; wpipe->pipe_buffer.cnt = size; wpipe->pipe_state &= ~PIPE_DIRECTW; PIPE_GET_GIANT(wpipe); pipe_destroy_write_buffer(wpipe); PIPE_DROP_GIANT(wpipe); } /* * This implements the pipe buffer write mechanism. Note that only * a direct write OR a normal pipe write can be pending at any given time. * If there are any characters in the pipe buffer, the direct write will * be deferred until the receiving process grabs all of the bytes from * the pipe buffer. Then the direct mapping write is set-up. */ static int pipe_direct_write(wpipe, uio) struct pipe *wpipe; struct uio *uio; { int error; retry: PIPE_LOCK_ASSERT(wpipe, MA_OWNED); while (wpipe->pipe_state & PIPE_DIRECTW) { if (wpipe->pipe_state & PIPE_WANTR) { wpipe->pipe_state &= ~PIPE_WANTR; wakeup(wpipe); } wpipe->pipe_state |= PIPE_WANTW; error = msleep(wpipe, PIPE_MTX(wpipe), PRIBIO | PCATCH, "pipdww", 0); if (error) goto error1; if (wpipe->pipe_state & PIPE_EOF) { error = EPIPE; goto error1; } } wpipe->pipe_map.cnt = 0; /* transfer not ready yet */ if (wpipe->pipe_buffer.cnt > 0) { if (wpipe->pipe_state & PIPE_WANTR) { wpipe->pipe_state &= ~PIPE_WANTR; wakeup(wpipe); } wpipe->pipe_state |= PIPE_WANTW; error = msleep(wpipe, PIPE_MTX(wpipe), PRIBIO | PCATCH, "pipdwc", 0); if (error) goto error1; if (wpipe->pipe_state & PIPE_EOF) { error = EPIPE; goto error1; } goto retry; } wpipe->pipe_state |= PIPE_DIRECTW; PIPE_GET_GIANT(wpipe); error = pipe_build_write_buffer(wpipe, uio); PIPE_DROP_GIANT(wpipe); if (error) { wpipe->pipe_state &= ~PIPE_DIRECTW; goto error1; } error = 0; while (!error && (wpipe->pipe_state & PIPE_DIRECTW)) { if (wpipe->pipe_state & PIPE_EOF) { pipelock(wpipe, 0); PIPE_GET_GIANT(wpipe); pipe_destroy_write_buffer(wpipe); PIPE_DROP_GIANT(wpipe); pipeunlock(wpipe); pipeselwakeup(wpipe, wpipe); error = EPIPE; goto error1; } if (wpipe->pipe_state & PIPE_WANTR) { wpipe->pipe_state &= ~PIPE_WANTR; wakeup(wpipe); } pipeselwakeup(wpipe, wpipe); error = msleep(wpipe, PIPE_MTX(wpipe), PRIBIO | PCATCH, "pipdwt", 0); } pipelock(wpipe,0); if (wpipe->pipe_state & PIPE_DIRECTW) { /* * this bit of trickery substitutes a kernel buffer for * the process that might be going away. */ pipe_clone_write_buffer(wpipe); } else { PIPE_GET_GIANT(wpipe); pipe_destroy_write_buffer(wpipe); PIPE_DROP_GIANT(wpipe); } pipeunlock(wpipe); return (error); error1: wakeup(wpipe); return (error); } #endif /* !PIPE_NODIRECT */ #endif /* FreeBSD */ #ifdef __NetBSD__ #ifndef PIPE_NODIRECT /* * Allocate structure for loan transfer. */ static int pipe_loan_alloc(wpipe, npages) struct pipe *wpipe; int npages; { vsize_t len; len = (vsize_t)npages << PAGE_SHIFT; wpipe->pipe_map.kva = uvm_km_valloc_wait(kernel_map, len); if (wpipe->pipe_map.kva == 0) return (ENOMEM); amountpipekva += len; wpipe->pipe_map.npages = npages; wpipe->pipe_map.pgs = malloc(npages * sizeof(struct vm_page *), M_PIPE, M_WAITOK); return (0); } /* * Free resources allocated for loan transfer. */ static void pipe_loan_free(wpipe) struct pipe *wpipe; { vsize_t len; len = (vsize_t)wpipe->pipe_map.npages << PAGE_SHIFT; uvm_km_free(kernel_map, wpipe->pipe_map.kva, len); wpipe->pipe_map.kva = 0; amountpipekva -= len; free(wpipe->pipe_map.pgs, M_PIPE); wpipe->pipe_map.pgs = NULL; } /* * NetBSD direct write, using uvm_loan() mechanism. * This implements the pipe buffer write mechanism. Note that only * a direct write OR a normal pipe write can be pending at any given time. * If there are any characters in the pipe buffer, the direct write will * be deferred until the receiving process grabs all of the bytes from * the pipe buffer. Then the direct mapping write is set-up. */ static int pipe_direct_write(wpipe, uio) struct pipe *wpipe; struct uio *uio; { int error, npages, j; struct vm_page **pgs; vaddr_t bbase, kva, base, bend; vsize_t blen, bcnt; voff_t bpos; retry: while (wpipe->pipe_state & PIPE_DIRECTW) { if (wpipe->pipe_state & PIPE_WANTR) { wpipe->pipe_state &= ~PIPE_WANTR; wakeup(wpipe); } wpipe->pipe_state |= PIPE_WANTW; error = tsleep(wpipe, PRIBIO | PCATCH, "pipdww", 0); if (error) goto error; if (wpipe->pipe_state & PIPE_EOF) { error = EPIPE; goto error; } } wpipe->pipe_map.cnt = 0; /* transfer not ready yet */ if (wpipe->pipe_buffer.cnt > 0) { if (wpipe->pipe_state & PIPE_WANTR) { wpipe->pipe_state &= ~PIPE_WANTR; wakeup(wpipe); } wpipe->pipe_state |= PIPE_WANTW; error = tsleep(wpipe, PRIBIO | PCATCH, "pipdwc", 0); if (error) goto error; if (wpipe->pipe_state & PIPE_EOF) { error = EPIPE; goto error; } goto retry; } /* * Handle first PIPE_CHUNK_SIZE bytes of buffer. Deal with buffers * not aligned to PAGE_SIZE. */ bbase = (vaddr_t)uio->uio_iov->iov_base; base = trunc_page(bbase); bend = round_page(bbase + uio->uio_iov->iov_len); blen = bend - base; bpos = bbase - base; if (blen > PIPE_DIRECT_CHUNK) { blen = PIPE_DIRECT_CHUNK; bend = base + blen; bcnt = PIPE_DIRECT_CHUNK - bpos; } else { bcnt = uio->uio_iov->iov_len; } npages = blen >> PAGE_SHIFT; wpipe->pipe_map.pos = bpos; wpipe->pipe_map.cnt = bcnt; /* * Free the old kva if we need more pages than we have * allocated. */ if (wpipe->pipe_map.kva && npages > wpipe->pipe_map.npages) pipe_loan_free(wpipe); /* Allocate new kva. */ if (wpipe->pipe_map.kva == 0) { error = pipe_loan_alloc(wpipe, npages); if (error) { goto error; } } /* Loan the write buffer memory from writer process */ pgs = wpipe->pipe_map.pgs; error = uvm_loan(&uio->uio_procp->p_vmspace->vm_map, base, blen, pgs, UVM_LOAN_TOPAGE); if (error) { pgs = NULL; goto cleanup; } /* Enter the loaned pages to kva */ kva = wpipe->pipe_map.kva; for (j = 0; j < npages; j++, kva += PAGE_SIZE) { pmap_kenter_pa(kva, VM_PAGE_TO_PHYS(pgs[j]), VM_PROT_READ); } pmap_update(pmap_kernel()); wpipe->pipe_state |= PIPE_DIRECTW; while (!error && (wpipe->pipe_state & PIPE_DIRECTW)) { if (wpipe->pipe_state & PIPE_EOF) { error = EPIPE; break; } if (wpipe->pipe_state & PIPE_WANTR) { wpipe->pipe_state &= ~PIPE_WANTR; wakeup(wpipe); } pipeselwakeup(wpipe, wpipe); error = tsleep(wpipe, PRIBIO | PCATCH, "pipdwt", 0); } if (error) wpipe->pipe_state &= ~PIPE_DIRECTW; cleanup: pipelock(wpipe, 0); if (pgs != NULL) { pmap_kremove(wpipe->pipe_map.kva, blen); uvm_unloan(pgs, npages, UVM_LOAN_TOPAGE); } if (error || amountpipekva > maxpipekva) pipe_loan_free(wpipe); pipeunlock(wpipe); if (error) { pipeselwakeup(wpipe, wpipe); /* * If nothing was read from what we offered, return error * straight on. Otherwise update uio resid first. Caller * will deal with the error condition, returning short * write, error, or restarting the write(2) as appropriate. */ if (wpipe->pipe_map.cnt == bcnt) { error: wakeup(wpipe); return (error); } bcnt -= wpipe->pipe_map.cnt; } uio->uio_resid -= bcnt; /* uio_offset not updated, not set/used for write(2) */ uio->uio_iov->iov_base = (char *)uio->uio_iov->iov_base + bcnt; uio->uio_iov->iov_len -= bcnt; if (uio->uio_iov->iov_len == 0) { uio->uio_iov++; uio->uio_iovcnt--; } return (error); } #endif /* !PIPE_NODIRECT */ #endif /* NetBSD */ #ifdef __FreeBSD__ static int pipe_write(fp, uio, cred, flags, td) struct file *fp; off_t *offset; struct uio *uio; struct ucred *cred; int flags; struct thread *td; #elif defined(__NetBSD__) static int pipe_write(fp, offset, uio, cred, flags) struct file *fp; off_t *offset; struct uio *uio; struct ucred *cred; int flags; #endif { int error = 0; struct pipe *wpipe, *rpipe; rpipe = (struct pipe *) fp->f_data; wpipe = rpipe->pipe_peer; PIPE_LOCK(rpipe); /* * detect loss of pipe read side, issue SIGPIPE if lost. */ if ((wpipe == NULL) || (wpipe->pipe_state & PIPE_EOF)) { PIPE_UNLOCK(rpipe); return (EPIPE); } ++wpipe->pipe_busy; /* * If it is advantageous to resize the pipe buffer, do * so. */ if ((uio->uio_resid > PIPE_SIZE) && (nbigpipe < maxbigpipes) && #ifndef PIPE_NODIRECT (wpipe->pipe_state & PIPE_DIRECTW) == 0 && #endif (wpipe->pipe_buffer.size <= PIPE_SIZE) && (wpipe->pipe_buffer.cnt == 0)) { if ((error = pipelock(wpipe,1)) == 0) { PIPE_GET_GIANT(rpipe); if (pipespace(wpipe, BIG_PIPE_SIZE) == 0) nbigpipe++; PIPE_DROP_GIANT(rpipe); pipeunlock(wpipe); } else { /* * If an error occurred, unbusy and return, waking up * any waiting readers. */ --wpipe->pipe_busy; if (wpipe->pipe_busy == 0 && (wpipe->pipe_state & PIPE_WANTCLOSE)) { wpipe->pipe_state &= ~(PIPE_WANTCLOSE | PIPE_WANTR); wakeup(wpipe); } return (error); } } #ifdef __FreeBSD__ /* * If an early error occured unbusy and return, waking up any pending * readers. */ if (error) { --wpipe->pipe_busy; if ((wpipe->pipe_busy == 0) && (wpipe->pipe_state & PIPE_WANT)) { wpipe->pipe_state &= ~(PIPE_WANT | PIPE_WANTR); wakeup(wpipe); } PIPE_UNLOCK(rpipe); return(error); } KASSERT(wpipe->pipe_buffer.buffer != NULL, ("pipe buffer gone")); #endif while (uio->uio_resid) { size_t space; #ifndef PIPE_NODIRECT /* * If the transfer is large, we can gain performance if * we do process-to-process copies directly. * If the write is non-blocking, we don't use the * direct write mechanism. * * The direct write mechanism will detect the reader going * away on us. */ if ((uio->uio_iov->iov_len >= PIPE_MINDIRECT) && (fp->f_flag & FNONBLOCK) == 0 && (wpipe->pipe_map.kva || (amountpipekva < limitpipekva))) { error = pipe_direct_write(wpipe, uio); /* * Break out if error occured, unless it's ENOMEM. * ENOMEM means we failed to allocate some resources * for direct write, so we just fallback to ordinary * write. If the direct write was successful, * process rest of data via ordinary write. */ if (!error) continue; if (error != ENOMEM) break; } #endif /* PIPE_NODIRECT */ /* * Pipe buffered writes cannot be coincidental with * direct writes. We wait until the currently executing * direct write is completed before we start filling the * pipe buffer. We break out if a signal occurs or the * reader goes away. */ retrywrite: while (wpipe->pipe_state & PIPE_DIRECTW) { if (wpipe->pipe_state & PIPE_WANTR) { wpipe->pipe_state &= ~PIPE_WANTR; wakeup(wpipe); } #ifdef __FreeBSD__ error = msleep(wpipe, PIPE_MTX(rpipe), PRIBIO | PCATCH, "pipbww", 0); #else error = tsleep(wpipe, PRIBIO | PCATCH, "pipbww", 0); #endif if (wpipe->pipe_state & PIPE_EOF) break; if (error) break; } if (wpipe->pipe_state & PIPE_EOF) { error = EPIPE; break; } space = wpipe->pipe_buffer.size - wpipe->pipe_buffer.cnt; /* Writes of size <= PIPE_BUF must be atomic. */ if ((space < uio->uio_resid) && (uio->uio_resid <= PIPE_BUF)) space = 0; if (space > 0) { int size; /* Transfer size */ int segsize; /* first segment to transfer */ if ((error = pipelock(wpipe,1)) != 0) break; /* * It is possible for a direct write to * slip in on us... handle it here... */ if (wpipe->pipe_state & PIPE_DIRECTW) { pipeunlock(wpipe); goto retrywrite; } /* * If a process blocked in uiomove, our * value for space might be bad. * * XXX will we be ok if the reader has gone * away here? */ if (space > wpipe->pipe_buffer.size - wpipe->pipe_buffer.cnt) { pipeunlock(wpipe); goto retrywrite; } /* * Transfer size is minimum of uio transfer * and free space in pipe buffer. */ if (space > uio->uio_resid) size = uio->uio_resid; else size = space; /* * First segment to transfer is minimum of * transfer size and contiguous space in * pipe buffer. If first segment to transfer * is less than the transfer size, we've got * a wraparound in the buffer. */ segsize = wpipe->pipe_buffer.size - wpipe->pipe_buffer.in; if (segsize > size) segsize = size; /* Transfer first segment */ PIPE_UNLOCK(rpipe); error = uiomove(&wpipe->pipe_buffer.buffer[wpipe->pipe_buffer.in], segsize, uio); PIPE_LOCK(rpipe); if (error == 0 && segsize < size) { /* * Transfer remaining part now, to * support atomic writes. Wraparound * happened. */ #ifdef DEBUG if (wpipe->pipe_buffer.in + segsize != wpipe->pipe_buffer.size) panic("Expected pipe buffer wraparound disappeared"); #endif PIPE_UNLOCK(rpipe); error = uiomove(&wpipe->pipe_buffer.buffer[0], size - segsize, uio); PIPE_LOCK(rpipe); } if (error == 0) { wpipe->pipe_buffer.in += size; if (wpipe->pipe_buffer.in >= wpipe->pipe_buffer.size) { #ifdef DEBUG if (wpipe->pipe_buffer.in != size - segsize + wpipe->pipe_buffer.size) panic("Expected wraparound bad"); #endif wpipe->pipe_buffer.in = size - segsize; } wpipe->pipe_buffer.cnt += size; #ifdef DEBUG if (wpipe->pipe_buffer.cnt > wpipe->pipe_buffer.size) panic("Pipe buffer overflow"); #endif } pipeunlock(wpipe); if (error) break; } else { /* * If the "read-side" has been blocked, wake it up now. */ if (wpipe->pipe_state & PIPE_WANTR) { wpipe->pipe_state &= ~PIPE_WANTR; wakeup(wpipe); } /* * don't block on non-blocking I/O */ if (fp->f_flag & FNONBLOCK) { error = EAGAIN; break; } /* * We have no more space and have something to offer, * wake up select/poll. */ pipeselwakeup(wpipe, wpipe); wpipe->pipe_state |= PIPE_WANTW; #ifdef __FreeBSD__ error = msleep(wpipe, PIPE_MTX(rpipe), PRIBIO | PCATCH, "pipewr", 0); #else error = tsleep(wpipe, PRIBIO | PCATCH, "pipewr", 0); #endif if (error != 0) break; /* * If read side wants to go away, we just issue a signal * to ourselves. */ if (wpipe->pipe_state & PIPE_EOF) { error = EPIPE; break; } } } --wpipe->pipe_busy; if ((wpipe->pipe_busy == 0) && (wpipe->pipe_state & PIPE_WANTCLOSE)) { wpipe->pipe_state &= ~(PIPE_WANTCLOSE | PIPE_WANTR); wakeup(wpipe); } else if (wpipe->pipe_buffer.cnt > 0) { /* * If we have put any characters in the buffer, we wake up * the reader. */ if (wpipe->pipe_state & PIPE_WANTR) { wpipe->pipe_state &= ~PIPE_WANTR; wakeup(wpipe); } } /* * Don't return EPIPE if I/O was successful */ if ((error == EPIPE) && (wpipe->pipe_buffer.cnt == 0) && (uio->uio_resid == 0)) error = 0; if (error == 0) vfs_timestamp(&wpipe->pipe_mtime); /* * We have something to offer, wake up select/poll. * wpipe->pipe_map.cnt is always 0 in this point (direct write * is only done synchronously), so check only wpipe->pipe_buffer.cnt */ if (wpipe->pipe_buffer.cnt) pipeselwakeup(wpipe, wpipe); /* * Arrange for next read(2) to do a signal. */ wpipe->pipe_state |= PIPE_SIGNALR; PIPE_UNLOCK(rpipe); return (error); } /* * we implement a very minimal set of ioctls for compatibility with sockets. */ int #ifdef __FreeBSD__ pipe_ioctl(fp, cmd, data, td) struct file *fp; u_long cmd; caddr_t data; struct thread *td; #else pipe_ioctl(fp, cmd, data, p) struct file *fp; u_long cmd; caddr_t data; struct proc *p; #endif { struct pipe *mpipe = (struct pipe *)fp->f_data; switch (cmd) { case FIONBIO: return (0); case FIOASYNC: PIPE_LOCK(mpipe); if (*(int *)data) { mpipe->pipe_state |= PIPE_ASYNC; } else { mpipe->pipe_state &= ~PIPE_ASYNC; } PIPE_UNLOCK(mpipe); return (0); case FIONREAD: PIPE_LOCK(mpipe); #ifndef PIPE_NODIRECT if (mpipe->pipe_state & PIPE_DIRECTW) *(int *)data = mpipe->pipe_map.cnt; else #endif *(int *)data = mpipe->pipe_buffer.cnt; PIPE_UNLOCK(mpipe); return (0); #ifdef __FreeBSD__ case FIOSETOWN: return (fsetown(*(int *)data, &mpipe->pipe_sigio)); case FIOGETOWN: *(int *)data = fgetown(mpipe->pipe_sigio); return (0); /* This is deprecated, FIOSETOWN should be used instead. */ case TIOCSPGRP: return (fsetown(-(*(int *)data), &mpipe->pipe_sigio)); /* This is deprecated, FIOGETOWN should be used instead. */ case TIOCGPGRP: *(int *)data = -fgetown(mpipe->pipe_sigio); return (0); #endif /* FreeBSD */ #ifdef __NetBSD__ case TIOCSPGRP: mpipe->pipe_pgid = *(int *)data; return (0); case TIOCGPGRP: *(int *)data = mpipe->pipe_pgid; return (0); #endif /* NetBSD */ } return (EPASSTHROUGH); } int #ifdef __FreeBSD__ pipe_poll(fp, events, cred, td) struct file *fp; int events; struct ucred *cred; struct thread *td; #elif defined(__NetBSD__) pipe_poll(fp, events, td) struct file *fp; int events; struct proc *td; #endif { struct pipe *rpipe = (struct pipe *)fp->f_data; struct pipe *wpipe; int revents = 0; wpipe = rpipe->pipe_peer; PIPE_LOCK(rpipe); if (events & (POLLIN | POLLRDNORM)) if ((rpipe->pipe_buffer.cnt > 0) || #ifndef PIPE_NODIRECT (rpipe->pipe_state & PIPE_DIRECTW) || #endif (rpipe->pipe_state & PIPE_EOF)) revents |= events & (POLLIN | POLLRDNORM); if (events & (POLLOUT | POLLWRNORM)) if (wpipe == NULL || (wpipe->pipe_state & PIPE_EOF) || ( #ifndef PIPE_NODIRECT ((wpipe->pipe_state & PIPE_DIRECTW) == 0) && #endif (wpipe->pipe_buffer.size - wpipe->pipe_buffer.cnt) >= PIPE_BUF)) revents |= events & (POLLOUT | POLLWRNORM); if ((rpipe->pipe_state & PIPE_EOF) || (wpipe == NULL) || (wpipe->pipe_state & PIPE_EOF)) revents |= POLLHUP; if (revents == 0) { if (events & (POLLIN | POLLRDNORM)) { selrecord(td, &rpipe->pipe_sel); rpipe->pipe_state |= PIPE_SEL; } if (events & (POLLOUT | POLLWRNORM)) { selrecord(td, &wpipe->pipe_sel); wpipe->pipe_state |= PIPE_SEL; } } PIPE_UNLOCK(rpipe); return (revents); } static int #ifdef __FreeBSD__ pipe_stat(fp, ub, td) struct file *fp; struct stat *ub; struct thread *td; #else pipe_stat(fp, ub, td) struct file *fp; struct stat *ub; struct proc *td; #endif { struct pipe *pipe = (struct pipe *)fp->f_data; memset((caddr_t)ub, 0, sizeof(*ub)); ub->st_mode = S_IFIFO | S_IRUSR | S_IWUSR; ub->st_blksize = pipe->pipe_buffer.size; ub->st_size = pipe->pipe_buffer.cnt; ub->st_blocks = (ub->st_size) ? 1 : 0; #ifdef __FreeBSD__ ub->st_atimespec = pipe->pipe_atime; ub->st_mtimespec = pipe->pipe_mtime; ub->st_ctimespec = pipe->pipe_ctime; #endif /* FreeBSD */ #ifdef __NetBSD__ TIMEVAL_TO_TIMESPEC(&pipe->pipe_atime, &ub->st_atimespec) TIMEVAL_TO_TIMESPEC(&pipe->pipe_mtime, &ub->st_mtimespec); TIMEVAL_TO_TIMESPEC(&pipe->pipe_ctime, &ub->st_ctimespec); #endif /* NetBSD */ ub->st_uid = fp->f_cred->cr_uid; ub->st_gid = fp->f_cred->cr_gid; /* * Left as 0: st_dev, st_ino, st_nlink, st_rdev, st_flags, st_gen. * XXX (st_dev, st_ino) should be unique. */ return (0); } /* ARGSUSED */ static int #ifdef __FreeBSD__ pipe_close(fp, td) struct file *fp; struct thread *td; #else pipe_close(fp, td) struct file *fp; struct proc *td; #endif { struct pipe *cpipe = (struct pipe *)fp->f_data; #ifdef __FreeBSD__ fp->f_ops = &badfileops; funsetown(cpipe->pipe_sigio); #endif fp->f_data = NULL; pipeclose(cpipe); return (0); } static void pipe_free_kmem(cpipe) struct pipe *cpipe; { #ifdef __FreeBSD__ GIANT_REQUIRED; KASSERT(cpipe->pipe_mtxp == NULL || !mtx_owned(PIPE_MTX(cpipe)), ("pipespace: pipe mutex locked")); #endif if (cpipe->pipe_buffer.buffer != NULL) { if (cpipe->pipe_buffer.size > PIPE_SIZE) --nbigpipe; amountpipekva -= cpipe->pipe_buffer.size; #ifdef __FreeBSD__ kmem_free(kernel_map, (vm_offset_t)cpipe->pipe_buffer.buffer, cpipe->pipe_buffer.size); #elif defined(__NetBSD__) uvm_km_free(kernel_map, (vaddr_t)cpipe->pipe_buffer.buffer, cpipe->pipe_buffer.size); #endif /* NetBSD */ cpipe->pipe_buffer.buffer = NULL; } #ifndef PIPE_NODIRECT if (cpipe->pipe_map.kva != 0) { #ifdef __FreeBSD__ amountpipekva -= cpipe->pipe_buffer.size + PAGE_SIZE; kmem_free(kernel_map, cpipe->pipe_map.kva, cpipe->pipe_buffer.size + PAGE_SIZE); #elif defined(__NetBSD__) pipe_loan_free(cpipe); #endif /* NetBSD */ cpipe->pipe_map.cnt = 0; cpipe->pipe_map.kva = 0; cpipe->pipe_map.pos = 0; cpipe->pipe_map.npages = 0; } #endif /* !PIPE_NODIRECT */ } /* * shutdown the pipe */ static void pipeclose(cpipe) struct pipe *cpipe; { struct pipe *ppipe; #ifdef __FreeBSD__ int hadpeer = 0; #endif if (cpipe == NULL) return; /* partially created pipes won't have a valid mutex. */ if (PIPE_MTX(cpipe) != NULL) PIPE_LOCK(cpipe); pipeselwakeup(cpipe, cpipe); /* * If the other side is blocked, wake it up saying that * we want to close it down. */ while (cpipe->pipe_busy) { wakeup(cpipe); cpipe->pipe_state |= PIPE_WANTCLOSE | PIPE_EOF; #ifdef __FreeBSD__ msleep(cpipe, PIPE_MTX(cpipe), PRIBIO, "pipecl", 0); #else tsleep(cpipe, PRIBIO, "pipecl", 0); #endif } /* * Disconnect from peer */ if ((ppipe = cpipe->pipe_peer) != NULL) { #ifdef __FreeBSD__ hadpeer++; #endif pipeselwakeup(ppipe, ppipe); ppipe->pipe_state |= PIPE_EOF; wakeup(ppipe); #ifdef __FreeBSD__ KNOTE(&ppipe->pipe_sel.sel_note, 0); #endif ppipe->pipe_peer = NULL; } /* * free resources */ #ifdef __FreeBSD__ if (PIPE_MTX(cpipe) != NULL) { PIPE_UNLOCK(cpipe); if (!hadpeer) { mtx_destroy(PIPE_MTX(cpipe)); free(PIPE_MTX(cpipe), M_TEMP); } } mtx_lock(&Giant); pipe_free_kmem(cpipe); zfree(pipe_zone, cpipe); mtx_unlock(&Giant); #endif #ifdef __NetBSD__ if (PIPE_MTX(cpipe) != NULL) PIPE_UNLOCK(cpipe); pipe_free_kmem(cpipe); (void) lockmgr(&cpipe->pipe_lock, LK_DRAIN, NULL); pool_put(&pipe_pool, cpipe); #endif } static void filt_pipedetach(struct knote *kn) { struct pipe *cpipe = (struct pipe *)kn->kn_fp->f_data; switch(kn->kn_filter) { case EVFILT_WRITE: /* need the peer structure, not our own */ cpipe = cpipe->pipe_peer; /* if reader end already closed, just return */ if (!cpipe) return; break; default: /* nothing to do */ break; } #ifdef DIAGNOSTIC if (kn->kn_hook != cpipe) panic("filt_pipedetach: inconsistent knote"); #endif PIPE_LOCK(cpipe); SLIST_REMOVE(&cpipe->pipe_sel.sel_note, kn, knote, kn_selnext); PIPE_UNLOCK(cpipe); } /*ARGSUSED*/ static int filt_piperead(struct knote *kn, long hint) { struct pipe *rpipe = (struct pipe *)kn->kn_fp->f_data; struct pipe *wpipe = rpipe->pipe_peer; PIPE_LOCK(rpipe); kn->kn_data = rpipe->pipe_buffer.cnt; if ((kn->kn_data == 0) && (rpipe->pipe_state & PIPE_DIRECTW)) kn->kn_data = rpipe->pipe_map.cnt; if ((rpipe->pipe_state & PIPE_EOF) || (wpipe == NULL) || (wpipe->pipe_state & PIPE_EOF)) { kn->kn_flags |= EV_EOF; PIPE_UNLOCK(rpipe); return (1); } PIPE_UNLOCK(rpipe); return (kn->kn_data > 0); } /*ARGSUSED*/ static int filt_pipewrite(struct knote *kn, long hint) { struct pipe *rpipe = (struct pipe *)kn->kn_fp->f_data; struct pipe *wpipe = rpipe->pipe_peer; PIPE_LOCK(rpipe); if ((wpipe == NULL) || (wpipe->pipe_state & PIPE_EOF)) { kn->kn_data = 0; kn->kn_flags |= EV_EOF; PIPE_UNLOCK(rpipe); return (1); } kn->kn_data = wpipe->pipe_buffer.size - wpipe->pipe_buffer.cnt; if (wpipe->pipe_state & PIPE_DIRECTW) kn->kn_data = 0; PIPE_UNLOCK(rpipe); return (kn->kn_data >= PIPE_BUF); } static const struct filterops pipe_rfiltops = { 1, NULL, filt_pipedetach, filt_piperead }; static const struct filterops pipe_wfiltops = { 1, NULL, filt_pipedetach, filt_pipewrite }; /*ARGSUSED*/ static int pipe_kqfilter(struct file *fp, struct knote *kn) { struct pipe *cpipe; cpipe = (struct pipe *)kn->kn_fp->f_data; switch (kn->kn_filter) { case EVFILT_READ: kn->kn_fop = &pipe_rfiltops; break; case EVFILT_WRITE: kn->kn_fop = &pipe_wfiltops; cpipe = cpipe->pipe_peer; if (cpipe == NULL) { /* other end of pipe has been closed */ return (EBADF); } break; default: return (1); } kn->kn_hook = cpipe; PIPE_LOCK(cpipe); SLIST_INSERT_HEAD(&cpipe->pipe_sel.sel_note, kn, kn_selnext); PIPE_UNLOCK(cpipe); return (0); } #ifdef __NetBSD__ static int pipe_fcntl(fp, cmd, data, p) struct file *fp; u_int cmd; caddr_t data; struct proc *p; { if (cmd == F_SETFL) return (0); else return (EOPNOTSUPP); } /* * Handle pipe sysctls. */ int sysctl_dopipe(name, namelen, oldp, oldlenp, newp, newlen) int *name; u_int namelen; void *oldp; size_t *oldlenp; void *newp; size_t newlen; { /* All sysctl names at this level are terminal. */ if (namelen != 1) return (ENOTDIR); /* overloaded */ switch (name[0]) { case KERN_PIPE_MAXKVASZ: return (sysctl_int(oldp, oldlenp, newp, newlen, &maxpipekva)); case KERN_PIPE_LIMITKVA: return (sysctl_int(oldp, oldlenp, newp, newlen, &limitpipekva)); case KERN_PIPE_MAXBIGPIPES: return (sysctl_int(oldp, oldlenp, newp, newlen, &maxbigpipes)); case KERN_PIPE_NBIGPIPES: return (sysctl_rdint(oldp, oldlenp, newp, nbigpipe)); case KERN_PIPE_KVASIZE: return (sysctl_rdint(oldp, oldlenp, newp, amountpipekva)); default: return (EOPNOTSUPP); } /* NOTREACHED */ } /* * Initialize pipe structs. */ void pipe_init(void) { pool_init(&pipe_pool, sizeof(struct pipe), 0, 0, 0, "pipepl", NULL); } #endif /* __NetBSD __ */