2 * Copyright (c) 1982, 1986, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
10 * Copyright (c) 2014 The FreeBSD Foundation
12 * Portions of this software were developed by Konstantin Belousov
13 * under sponsorship from the FreeBSD Foundation.
15 * Redistribution and use in source and binary forms, with or without
16 * modification, are permitted provided that the following conditions
18 * 1. Redistributions of source code must retain the above copyright
19 * notice, this list of conditions and the following disclaimer.
20 * 2. Redistributions in binary form must reproduce the above copyright
21 * notice, this list of conditions and the following disclaimer in the
22 * documentation and/or other materials provided with the distribution.
23 * 3. Neither the name of the University nor the names of its contributors
24 * may be used to endorse or promote products derived from this software
25 * without specific prior written permission.
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39 * @(#)kern_subr.c 8.3 (Berkeley) 1/21/94
42 #include <sys/cdefs.h>
43 __FBSDID("$FreeBSD$");
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/kernel.h>
48 #include <sys/limits.h>
52 #include <sys/resourcevar.h>
53 #include <sys/rwlock.h>
54 #include <sys/sched.h>
55 #include <sys/sysctl.h>
56 #include <sys/vnode.h>
59 #include <vm/vm_param.h>
60 #include <vm/vm_extern.h>
61 #include <vm/vm_page.h>
62 #include <vm/vm_pageout.h>
63 #include <vm/vm_map.h>
65 #include <machine/bus.h>
67 SYSCTL_INT(_kern, KERN_IOV_MAX, iov_max, CTLFLAG_RD, SYSCTL_NULL_INT_PTR, UIO_MAXIOV,
68 "Maximum number of elements in an I/O vector; sysconf(_SC_IOV_MAX)");
70 static int uiomove_faultflag(void *cp, int n, struct uio *uio, int nofault);
73 copyin_nofault(const void *udaddr, void *kaddr, size_t len)
77 save = vm_fault_disable_pagefaults();
78 error = copyin(udaddr, kaddr, len);
79 vm_fault_enable_pagefaults(save);
84 copyout_nofault(const void *kaddr, void *udaddr, size_t len)
88 save = vm_fault_disable_pagefaults();
89 error = copyout(kaddr, udaddr, len);
90 vm_fault_enable_pagefaults(save);
94 #define PHYS_PAGE_COUNT(len) (howmany(len, PAGE_SIZE) + 1)
97 physcopyin(void *src, vm_paddr_t dst, size_t len)
99 vm_page_t m[PHYS_PAGE_COUNT(len)];
104 iov[0].iov_base = src;
105 iov[0].iov_len = len;
110 uio.uio_segflg = UIO_SYSSPACE;
111 uio.uio_rw = UIO_WRITE;
112 for (i = 0; i < PHYS_PAGE_COUNT(len); i++, dst += PAGE_SIZE)
113 m[i] = PHYS_TO_VM_PAGE(dst);
114 return (uiomove_fromphys(m, dst & PAGE_MASK, len, &uio));
118 physcopyout(vm_paddr_t src, void *dst, size_t len)
120 vm_page_t m[PHYS_PAGE_COUNT(len)];
125 iov[0].iov_base = dst;
126 iov[0].iov_len = len;
131 uio.uio_segflg = UIO_SYSSPACE;
132 uio.uio_rw = UIO_READ;
133 for (i = 0; i < PHYS_PAGE_COUNT(len); i++, src += PAGE_SIZE)
134 m[i] = PHYS_TO_VM_PAGE(src);
135 return (uiomove_fromphys(m, src & PAGE_MASK, len, &uio));
138 #undef PHYS_PAGE_COUNT
141 physcopyin_vlist(bus_dma_segment_t *src, off_t offset, vm_paddr_t dst,
148 while (offset >= src->ds_len) {
149 offset -= src->ds_len;
153 while (len > 0 && error == 0) {
154 seg_len = MIN(src->ds_len - offset, len);
155 error = physcopyin((void *)(uintptr_t)(src->ds_addr + offset),
167 physcopyout_vlist(vm_paddr_t src, bus_dma_segment_t *dst, off_t offset,
174 while (offset >= dst->ds_len) {
175 offset -= dst->ds_len;
179 while (len > 0 && error == 0) {
180 seg_len = MIN(dst->ds_len - offset, len);
181 error = physcopyout(src, (void *)(uintptr_t)(dst->ds_addr +
193 uiomove(void *cp, int n, struct uio *uio)
196 return (uiomove_faultflag(cp, n, uio, 0));
200 uiomove_nofault(void *cp, int n, struct uio *uio)
203 return (uiomove_faultflag(cp, n, uio, 1));
207 uiomove_faultflag(void *cp, int n, struct uio *uio, int nofault)
211 int error, newflags, save;
215 KASSERT(uio->uio_rw == UIO_READ || uio->uio_rw == UIO_WRITE,
217 KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread,
220 if (uio->uio_segflg == UIO_USERSPACE) {
221 newflags = TDP_DEADLKTREAT;
224 * Fail if a non-spurious page fault occurs.
226 newflags |= TDP_NOFAULTING | TDP_RESETSPUR;
228 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
229 "Calling uiomove()");
231 save = curthread_pflags_set(newflags);
233 KASSERT(nofault == 0, ("uiomove: nofault"));
236 while (n > 0 && uio->uio_resid) {
247 switch (uio->uio_segflg) {
251 if (uio->uio_rw == UIO_READ)
252 error = copyout(cp, iov->iov_base, cnt);
254 error = copyin(iov->iov_base, cp, cnt);
260 if (uio->uio_rw == UIO_READ)
261 bcopy(cp, iov->iov_base, cnt);
263 bcopy(iov->iov_base, cp, cnt);
268 iov->iov_base = (char *)iov->iov_base + cnt;
270 uio->uio_resid -= cnt;
271 uio->uio_offset += cnt;
272 cp = (char *)cp + cnt;
276 if (uio->uio_segflg == UIO_USERSPACE)
277 curthread_pflags_restore(save);
282 * Wrapper for uiomove() that validates the arguments against a known-good
283 * kernel buffer. Currently, uiomove accepts a signed (n) argument, which
284 * is almost definitely a bad thing, so we catch that here as well. We
285 * return a runtime failure, but it might be desirable to generate a runtime
286 * assertion failure instead.
289 uiomove_frombuf(void *buf, int buflen, struct uio *uio)
293 if (uio->uio_offset < 0 || uio->uio_resid < 0 ||
294 (offset = uio->uio_offset) != uio->uio_offset)
296 if (buflen <= 0 || offset >= buflen)
298 if ((n = buflen - offset) > IOSIZE_MAX)
300 return (uiomove((char *)buf + offset, n, uio));
304 * Give next character to user as result of read.
307 ureadc(int c, struct uio *uio)
312 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
316 if (uio->uio_iovcnt == 0 || uio->uio_resid == 0)
319 if (iov->iov_len == 0) {
324 switch (uio->uio_segflg) {
327 if (subyte(iov->iov_base, c) < 0)
332 iov_base = iov->iov_base;
339 iov->iov_base = (char *)iov->iov_base + 1;
347 copyinfrom(const void * __restrict src, void * __restrict dst, size_t len,
354 error = copyin(src, dst, len);
357 bcopy(src, dst, len);
360 panic("copyinfrom: bad seg %d\n", seg);
366 copyinstrfrom(const void * __restrict src, void * __restrict dst, size_t len,
367 size_t * __restrict copied, int seg)
373 error = copyinstr(src, dst, len, copied);
376 error = copystr(src, dst, len, copied);
379 panic("copyinstrfrom: bad seg %d\n", seg);
385 copyiniov(const struct iovec *iovp, u_int iovcnt, struct iovec **iov, int error)
390 if (iovcnt > UIO_MAXIOV)
392 iovlen = iovcnt * sizeof (struct iovec);
393 *iov = malloc(iovlen, M_IOV, M_WAITOK);
394 error = copyin(iovp, *iov, iovlen);
403 copyinuio(const struct iovec *iovp, u_int iovcnt, struct uio **uiop)
411 if (iovcnt > UIO_MAXIOV)
413 iovlen = iovcnt * sizeof (struct iovec);
414 uio = malloc(iovlen + sizeof *uio, M_IOV, M_WAITOK);
415 iov = (struct iovec *)(uio + 1);
416 error = copyin(iovp, iov, iovlen);
422 uio->uio_iovcnt = iovcnt;
423 uio->uio_segflg = UIO_USERSPACE;
424 uio->uio_offset = -1;
426 for (i = 0; i < iovcnt; i++) {
427 if (iov->iov_len > IOSIZE_MAX - uio->uio_resid) {
431 uio->uio_resid += iov->iov_len;
439 cloneuio(struct uio *uiop)
444 iovlen = uiop->uio_iovcnt * sizeof (struct iovec);
445 uio = malloc(iovlen + sizeof *uio, M_IOV, M_WAITOK);
447 uio->uio_iov = (struct iovec *)(uio + 1);
448 bcopy(uiop->uio_iov, uio->uio_iov, iovlen);
453 * Map some anonymous memory in user space of size sz, rounded up to the page
457 copyout_map(struct thread *td, vm_offset_t *addr, size_t sz)
463 vms = td->td_proc->p_vmspace;
466 * Map somewhere after heap in process memory.
468 *addr = round_page((vm_offset_t)vms->vm_daddr +
469 lim_max(td, RLIMIT_DATA));
471 /* round size up to page boundary */
472 size = (vm_size_t)round_page(sz);
475 error = vm_mmap_object(&vms->vm_map, addr, size, VM_PROT_READ |
476 VM_PROT_WRITE, VM_PROT_ALL, MAP_PRIVATE | MAP_ANON, NULL, 0,
482 * Unmap memory in user space.
485 copyout_unmap(struct thread *td, vm_offset_t addr, size_t sz)
493 map = &td->td_proc->p_vmspace->vm_map;
494 size = (vm_size_t)round_page(sz);
496 if (vm_map_remove(map, addr, addr + size) != KERN_SUCCESS)
504 * XXXKIB The temporal implementation of fue*() functions which do not
505 * handle usermode -1 properly, mixing it with the fault code. Keep
506 * this until MD code is written. Currently sparc64 and mips do not
507 * have proper implementation.
511 fueword(volatile const void *base, long *val)
523 fueword32(volatile const void *base, int32_t *val)
527 res = fuword32(base);
536 fueword64(volatile const void *base, int64_t *val)
540 res = fuword64(base);
549 casueword32(volatile uint32_t *base, uint32_t oldval, uint32_t *oldvalp,
554 ov = casuword32(base, oldval, newval);
562 casueword(volatile u_long *p, u_long oldval, u_long *oldvalp, u_long newval)
566 ov = casuword(p, oldval, newval);
572 #else /* NO_FUEWORD */
574 fuword32(volatile const void *addr)
579 rv = fueword32(addr, &val);
580 return (rv == -1 ? -1 : val);
585 fuword64(volatile const void *addr)
590 rv = fueword64(addr, &val);
591 return (rv == -1 ? -1 : val);
596 fuword(volatile const void *addr)
601 rv = fueword(addr, &val);
602 return (rv == -1 ? -1 : val);
606 casuword32(volatile uint32_t *addr, uint32_t old, uint32_t new)
611 rv = casueword32(addr, old, &val, new);
612 return (rv == -1 ? -1 : val);
616 casuword(volatile u_long *addr, u_long old, u_long new)
621 rv = casueword(addr, old, &val, new);
622 return (rv == -1 ? -1 : val);
625 #endif /* NO_FUEWORD */