/*- * Copyright (c) 1982, 1986 The Regents of the University of California. * Copyright (c) 1989, 1990 William Jolitz * Copyright (c) 1994 John Dyson * All rights reserved. * * This code is derived from software contributed to Berkeley by * the Systems Programming Group of the University of Utah Computer * Science Department, and William Jolitz. * * 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, 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from: @(#)vm_machdep.c 7.3 (Berkeley) 5/13/91 * Utah $Hdr: vm_machdep.c 1.16.1.1 89/06/23$ * $FreeBSD$ */ /*- * Copyright (c) 1994, 1995, 1996 Carnegie-Mellon University. * All rights reserved. * * Author: Chris G. Demetriou * * Permission to use, copy, modify and distribute this software and * its documentation is hereby granted, provided that both the copyright * notice and this permission notice appear in all copies of the * software, derivative works or modified versions, and any portions * thereof, and that both notices appear in supporting documentation. * * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. * * Carnegie Mellon requests users of this software to return to * * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU * School of Computer Science * Carnegie Mellon University * Pittsburgh PA 15213-3890 * * any improvements or extensions that they make and grant Carnegie the * rights to redistribute these changes. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * On systems without a direct mapped region (e.g. PPC64), * we use the same code as the Book E implementation. Since * we need to have runtime detection of this, define some machinery * for sf_bufs in this case, and ignore it on systems with direct maps. */ #ifndef NSFBUFS #define NSFBUFS (512 + maxusers * 16) #endif static void sf_buf_init(void *arg); SYSINIT(sock_sf, SI_SUB_MBUF, SI_ORDER_ANY, sf_buf_init, NULL); LIST_HEAD(sf_head, sf_buf); /* A hash table of active sendfile(2) buffers */ static struct sf_head *sf_buf_active; static u_long sf_buf_hashmask; #define SF_BUF_HASH(m) (((m) - vm_page_array) & sf_buf_hashmask) static TAILQ_HEAD(, sf_buf) sf_buf_freelist; static u_int sf_buf_alloc_want; /* * A lock used to synchronize access to the hash table and free list */ static struct mtx sf_buf_lock; #ifdef __powerpc64__ extern uintptr_t tocbase; #endif /* * Finish a fork operation, with process p2 nearly set up. * Copy and update the pcb, set up the stack so that the child * ready to run and return to user mode. */ void cpu_fork(struct thread *td1, struct proc *p2, struct thread *td2, int flags) { struct trapframe *tf; struct callframe *cf; struct pcb *pcb; KASSERT(td1 == curthread || td1 == &thread0, ("cpu_fork: p1 not curproc and not proc0")); CTR3(KTR_PROC, "cpu_fork: called td1=%p p2=%p flags=%x", td1, p2, flags); if ((flags & RFPROC) == 0) return; pcb = (struct pcb *)((td2->td_kstack + td2->td_kstack_pages * PAGE_SIZE - sizeof(struct pcb)) & ~0x2fUL); td2->td_pcb = pcb; /* Copy the pcb */ bcopy(td1->td_pcb, pcb, sizeof(struct pcb)); /* * Create a fresh stack for the new process. * Copy the trap frame for the return to user mode as if from a * syscall. This copies most of the user mode register values. */ tf = (struct trapframe *)pcb - 1; bcopy(td1->td_frame, tf, sizeof(*tf)); /* Set up trap frame. */ tf->fixreg[FIRSTARG] = 0; tf->fixreg[FIRSTARG + 1] = 0; tf->cr &= ~0x10000000; td2->td_frame = tf; cf = (struct callframe *)tf - 1; memset(cf, 0, sizeof(struct callframe)); #ifdef __powerpc64__ cf->cf_toc = tocbase; #endif cf->cf_func = (register_t)fork_return; cf->cf_arg0 = (register_t)td2; cf->cf_arg1 = (register_t)tf; pcb->pcb_sp = (register_t)cf; #ifdef __powerpc64__ pcb->pcb_lr = ((register_t *)fork_trampoline)[0]; pcb->pcb_toc = ((register_t *)fork_trampoline)[1]; #else pcb->pcb_lr = (register_t)fork_trampoline; #endif pcb->pcb_cpu.aim.usr_vsid = 0; /* Setup to release spin count in fork_exit(). */ td2->td_md.md_spinlock_count = 1; td2->td_md.md_saved_msr = PSL_KERNSET; /* * Now cpu_switch() can schedule the new process. */ } /* * Intercept the return address from a freshly forked process that has NOT * been scheduled yet. * * This is needed to make kernel threads stay in kernel mode. */ void cpu_set_fork_handler(td, func, arg) struct thread *td; void (*func)(void *); void *arg; { struct callframe *cf; CTR4(KTR_PROC, "%s called with td=%p func=%p arg=%p", __func__, td, func, arg); cf = (struct callframe *)td->td_pcb->pcb_sp; cf->cf_func = (register_t)func; cf->cf_arg0 = (register_t)arg; } void cpu_exit(td) register struct thread *td; { } /* * Allocate a pool of sf_bufs (sendfile(2) or "super-fast" if you prefer. :-)) */ static void sf_buf_init(void *arg) { struct sf_buf *sf_bufs; vm_offset_t sf_base; int i; /* Don't bother on systems with a direct map */ if (hw_direct_map) return; nsfbufs = NSFBUFS; TUNABLE_INT_FETCH("kern.ipc.nsfbufs", &nsfbufs); sf_buf_active = hashinit(nsfbufs, M_TEMP, &sf_buf_hashmask); TAILQ_INIT(&sf_buf_freelist); sf_base = kmem_alloc_nofault(kernel_map, nsfbufs * PAGE_SIZE); sf_bufs = malloc(nsfbufs * sizeof(struct sf_buf), M_TEMP, M_NOWAIT | M_ZERO); for (i = 0; i < nsfbufs; i++) { sf_bufs[i].kva = sf_base + i * PAGE_SIZE; TAILQ_INSERT_TAIL(&sf_buf_freelist, &sf_bufs[i], free_entry); } sf_buf_alloc_want = 0; mtx_init(&sf_buf_lock, "sf_buf", NULL, MTX_DEF); } /* * Get an sf_buf from the freelist. Will block if none are available. */ struct sf_buf * sf_buf_alloc(struct vm_page *m, int flags) { struct sf_head *hash_list; struct sf_buf *sf; int error; if (hw_direct_map) { /* Shortcut the direct mapped case */ return ((struct sf_buf *)m); } hash_list = &sf_buf_active[SF_BUF_HASH(m)]; mtx_lock(&sf_buf_lock); LIST_FOREACH(sf, hash_list, list_entry) { if (sf->m == m) { sf->ref_count++; if (sf->ref_count == 1) { TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry); nsfbufsused++; nsfbufspeak = imax(nsfbufspeak, nsfbufsused); } goto done; } } while ((sf = TAILQ_FIRST(&sf_buf_freelist)) == NULL) { if (flags & SFB_NOWAIT) goto done; sf_buf_alloc_want++; mbstat.sf_allocwait++; error = msleep(&sf_buf_freelist, &sf_buf_lock, (flags & SFB_CATCH) ? PCATCH | PVM : PVM, "sfbufa", 0); sf_buf_alloc_want--; /* * If we got a signal, don't risk going back to sleep. */ if (error) goto done; } TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry); if (sf->m != NULL) LIST_REMOVE(sf, list_entry); LIST_INSERT_HEAD(hash_list, sf, list_entry); sf->ref_count = 1; sf->m = m; nsfbufsused++; nsfbufspeak = imax(nsfbufspeak, nsfbufsused); pmap_qenter(sf->kva, &sf->m, 1); done: mtx_unlock(&sf_buf_lock); return (sf); } /* * Detatch mapped page and release resources back to the system. * * Remove a reference from the given sf_buf, adding it to the free * list when its reference count reaches zero. A freed sf_buf still, * however, retains its virtual-to-physical mapping until it is * recycled or reactivated by sf_buf_alloc(9). */ void sf_buf_free(struct sf_buf *sf) { if (hw_direct_map) return; mtx_lock(&sf_buf_lock); sf->ref_count--; if (sf->ref_count == 0) { TAILQ_INSERT_TAIL(&sf_buf_freelist, sf, free_entry); nsfbufsused--; if (sf_buf_alloc_want > 0) wakeup(&sf_buf_freelist); } mtx_unlock(&sf_buf_lock); } /* * Software interrupt handler for queued VM system processing. */ void swi_vm(void *dummy) { if (busdma_swi_pending != 0) busdma_swi(); } /* * Tell whether this address is in some physical memory region. * Currently used by the kernel coredump code in order to avoid * dumping the ``ISA memory hole'' which could cause indefinite hangs, * or other unpredictable behaviour. */ int is_physical_memory(addr) vm_offset_t addr; { /* * stuff other tests for known memory-mapped devices (PCI?) * here */ return 1; } /* * CPU threading functions related to the VM layer. These could be used * to map the SLB bits required for the kernel stack instead of forcing a * fixed-size KVA. */ void cpu_thread_swapin(struct thread *td) { } void cpu_thread_swapout(struct thread *td) { }