2 * Copyright (c) 2013-2015 Gleb Smirnoff <glebius@FreeBSD.org>
3 * Copyright (c) 1998, David Greenman. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 #include <sys/cdefs.h>
31 #include "opt_kern_tls.h"
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/capsicum.h>
36 #include <sys/kernel.h>
39 #include <sys/mutex.h>
40 #include <sys/malloc.h>
42 #include <sys/mount.h>
45 #include <sys/protosw.h>
46 #include <sys/rwlock.h>
47 #include <sys/sf_buf.h>
48 #include <sys/socket.h>
49 #include <sys/socketvar.h>
50 #include <sys/syscallsubr.h>
51 #include <sys/sysctl.h>
52 #include <sys/sysproto.h>
53 #include <sys/vnode.h>
56 #include <netinet/in.h>
57 #include <netinet/tcp.h>
58 #include <netinet/in_pcb.h>
59 #include <netinet/tcp_var.h>
60 #include <netinet/tcp_log_buf.h>
62 #include <security/audit/audit.h>
63 #include <security/mac/mac_framework.h>
66 #include <vm/vm_object.h>
67 #include <vm/vm_pager.h>
69 static MALLOC_DEFINE(M_SENDFILE, "sendfile", "sendfile dynamic memory");
71 #define EXT_FLAG_SYNC EXT_FLAG_VENDOR1
72 #define EXT_FLAG_NOCACHE EXT_FLAG_VENDOR2
73 #define EXT_FLAG_CACHE_LAST EXT_FLAG_VENDOR3
76 * Structure describing a single sendfile(2) I/O, which may consist of
77 * several underlying pager I/Os.
79 * The syscall context allocates the structure and initializes 'nios'
80 * to 1. As sendfile_swapin() runs through pages and starts asynchronous
81 * paging operations, it increments 'nios'.
83 * Every I/O completion calls sendfile_iodone(), which decrements the 'nios',
84 * and the syscall also calls sendfile_iodone() after allocating all mbufs,
85 * linking them and sending to socket. Whoever reaches zero 'nios' is
86 * responsible to * call pru_ready on the socket, to notify it of readyness
98 struct ktls_session *tls;
104 * Structure used to track requests with SF_SYNC flag.
106 struct sendfile_sync {
114 sendfile_sync_destroy(struct sendfile_sync *sfs)
116 KASSERT(sfs->count == 0, ("sendfile sync %p still busy", sfs));
118 cv_destroy(&sfs->cv);
119 mtx_destroy(&sfs->mtx);
120 free(sfs, M_SENDFILE);
124 sendfile_sync_signal(struct sendfile_sync *sfs)
127 KASSERT(sfs->count > 0, ("sendfile sync %p not busy", sfs));
128 if (--sfs->count == 0) {
130 /* The sendfile() waiter was interrupted by a signal. */
131 sendfile_sync_destroy(sfs);
137 mtx_unlock(&sfs->mtx);
140 counter_u64_t sfstat[sizeof(struct sfstat) / sizeof(uint64_t)];
143 sfstat_init(const void *unused)
146 COUNTER_ARRAY_ALLOC(sfstat, sizeof(struct sfstat) / sizeof(uint64_t),
149 SYSINIT(sfstat, SI_SUB_MBUF, SI_ORDER_FIRST, sfstat_init, NULL);
152 sfstat_sysctl(SYSCTL_HANDLER_ARGS)
156 COUNTER_ARRAY_COPY(sfstat, &s, sizeof(s) / sizeof(uint64_t));
158 COUNTER_ARRAY_ZERO(sfstat, sizeof(s) / sizeof(uint64_t));
159 return (SYSCTL_OUT(req, &s, sizeof(s)));
161 SYSCTL_PROC(_kern_ipc, OID_AUTO, sfstat,
162 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_MPSAFE, NULL, 0,
164 "sendfile statistics");
167 sendfile_free_mext(struct mbuf *m)
173 KASSERT(m->m_flags & M_EXT && m->m_ext.ext_type == EXT_SFBUF,
174 ("%s: m %p !M_EXT or !EXT_SFBUF", __func__, m));
176 sf = m->m_ext.ext_arg1;
177 pg = sf_buf_page(sf);
178 flags = (m->m_ext.ext_flags & EXT_FLAG_NOCACHE) != 0 ? VPR_TRYFREE : 0;
181 vm_page_release(pg, flags);
183 if (m->m_ext.ext_flags & EXT_FLAG_SYNC) {
184 struct sendfile_sync *sfs = m->m_ext.ext_arg2;
185 sendfile_sync_signal(sfs);
190 sendfile_free_mext_pg(struct mbuf *m)
198 cache_last = m->m_ext.ext_flags & EXT_FLAG_CACHE_LAST;
199 flags = (m->m_ext.ext_flags & EXT_FLAG_NOCACHE) != 0 ? VPR_TRYFREE : 0;
201 for (i = 0; i < m->m_epg_npgs; i++) {
202 if (cache_last && i == m->m_epg_npgs - 1)
204 pg = PHYS_TO_VM_PAGE(m->m_epg_pa[i]);
205 vm_page_release(pg, flags);
208 if (m->m_ext.ext_flags & EXT_FLAG_SYNC) {
209 struct sendfile_sync *sfs = m->m_ext.ext_arg1;
210 sendfile_sync_signal(sfs);
215 * Helper function to calculate how much data to put into page i of n.
216 * Only first and last pages are special.
219 xfsize(int i, int n, off_t off, off_t len)
223 return (omin(PAGE_SIZE - (off & PAGE_MASK), len));
225 if (i == n - 1 && ((off + len) & PAGE_MASK) > 0)
226 return ((off + len) & PAGE_MASK);
232 * Helper function to get offset within object for i page.
234 static inline vm_ooffset_t
235 vmoff(int i, off_t off)
239 return ((vm_ooffset_t)off);
241 return (trunc_page(off + i * PAGE_SIZE));
245 * Helper function used when allocation of a page or sf_buf failed.
246 * Pretend as if we don't have enough space, subtract xfsize() of
247 * all pages that failed.
250 fixspace(int old, int new, off_t off, int *space)
253 KASSERT(old > new, ("%s: old %d new %d", __func__, old, new));
255 /* Subtract last one. */
256 *space -= xfsize(old - 1, old, off, *space);
260 /* There was only one page. */
263 /* Subtract first one. */
265 *space -= xfsize(0, old, off, *space);
269 /* Rest of pages are full sized. */
270 *space -= (old - new) * PAGE_SIZE;
272 KASSERT(*space >= 0, ("%s: space went backwards", __func__));
276 * Wait for all in-flight ios to complete, we must not unwire pages
280 sendfile_iowait(struct sf_io *sfio, const char *wmesg)
282 while (atomic_load_int(&sfio->nios) != 1)
287 * I/O completion callback.
290 sendfile_iodone(void *arg, vm_page_t *pa, int count, int error)
292 struct sf_io *sfio = arg;
300 * Restore the valid page pointers. They are already
301 * unbusied, but still wired.
303 * XXXKIB since pages are only wired, and we do not
304 * own the object lock, other users might have
305 * invalidated them in meantime. Similarly, after we
306 * unbusied the swapped-in pages, they can become
309 MPASS(count == 0 || pa[0] != bogus_page);
310 for (i = 0; i < count; i++) {
311 if (pa[i] == bogus_page) {
312 sfio->pa[(pa[0]->pindex - sfio->pindex0) + i] =
313 pa[i] = vm_page_relookup(sfio->obj,
315 KASSERT(pa[i] != NULL,
316 ("%s: page %p[%d] disappeared",
319 vm_page_xunbusy_unchecked(pa[i]);
323 if (!refcount_release(&sfio->nios))
327 for (i = 1; i < sfio->npages; i++) {
328 if (sfio->pa[i] == NULL)
330 KASSERT(vm_page_wired(sfio->pa[i]),
331 ("sfio %p page %d %p not wired", sfio, i, sfio->pa[i]));
334 KASSERT(sfio->pa[0]->object == sfio->pa[i]->object,
335 ("sfio %p page %d %p wrong owner %p %p", sfio, i,
336 sfio->pa[i], sfio->pa[0]->object, sfio->pa[i]->object));
337 KASSERT(sfio->pa[0]->pindex + i == sfio->pa[i]->pindex,
338 ("sfio %p page %d %p wrong index %jx %jx", sfio, i,
339 sfio->pa[i], (uintmax_t)sfio->pa[0]->pindex,
340 (uintmax_t)sfio->pa[i]->pindex));
344 vm_object_pip_wakeup(sfio->obj);
346 if (sfio->m == NULL) {
348 * Either I/O operation failed, or we failed to allocate
349 * buffers, or we bailed out on first busy page, or we
350 * succeeded filling the request without any I/Os. Anyway,
351 * pru_send hadn't been executed - nothing had been sent
354 MPASS((curthread->td_pflags & TDP_KTHREAD) == 0);
355 free(sfio, M_SENDFILE);
359 #if defined(KERN_TLS) && defined(INVARIANTS)
360 if ((sfio->m->m_flags & M_EXTPG) != 0)
361 KASSERT(sfio->tls == sfio->m->m_epg_tls,
362 ("TLS session mismatch"));
364 KASSERT(sfio->tls == NULL,
365 ("non-ext_pgs mbuf with TLS session"));
368 CURVNET_SET(so->so_vnet);
369 if (__predict_false(sfio->error)) {
371 * I/O operation failed. The state of data in the socket
372 * is now inconsistent, and all what we can do is to tear
373 * it down. Protocol abort method would tear down protocol
374 * state, free all ready mbufs and detach not ready ones.
375 * We will free the mbufs corresponding to this I/O manually.
377 * The socket would be marked with EIO and made available
378 * for read, so that application receives EIO on next
379 * syscall and eventually closes the socket.
381 so->so_proto->pr_abort(so);
384 mb_free_notready(sfio->m, sfio->npages);
386 } else if (sfio->tls != NULL && sfio->tls->mode == TCP_TLS_MODE_SW) {
388 * I/O operation is complete, but we still need to
389 * encrypt. We cannot do this in the interrupt thread
390 * of the disk controller, so forward the mbufs to a
393 * Donate the socket reference from sfio to rather
394 * than explicitly invoking soref().
396 ktls_enqueue(sfio->m, so, sfio->npages);
400 (void)so->so_proto->pr_ready(so, sfio->m, sfio->npages);
407 free(sfio, M_SENDFILE);
411 * Iterate through pages vector and request paging for non-valid pages.
414 sendfile_swapin(vm_object_t obj, struct sf_io *sfio, int *nios, off_t off,
415 off_t len, int rhpages, int flags)
418 int a, count, count1, grabbed, i, j, npages, rv;
421 npages = sfio->npages;
423 flags = (flags & SF_NODISKIO) ? VM_ALLOC_NOWAIT : 0;
424 sfio->pindex0 = OFF_TO_IDX(off);
427 * First grab all the pages and wire them. Note that we grab
428 * only required pages. Readahead pages are dealt with later.
430 grabbed = vm_page_grab_pages_unlocked(obj, OFF_TO_IDX(off),
431 VM_ALLOC_NORMAL | VM_ALLOC_WIRED | flags, pa, npages);
432 if (grabbed < npages) {
433 for (int i = grabbed; i < npages; i++)
439 for (i = 0; i < npages;) {
440 /* Skip valid pages. */
441 if (vm_page_is_valid(pa[i], vmoff(i, off) & PAGE_MASK,
442 xfsize(i, npages, off, len))) {
443 vm_page_xunbusy(pa[i]);
444 SFSTAT_INC(sf_pages_valid);
450 * Next page is invalid. Check if it belongs to pager. It
451 * may not be there, which is a regular situation for shmem
452 * pager. For vnode pager this happens only in case of
455 * Important feature of vm_pager_has_page() is the hint
456 * stored in 'a', about how many pages we can pagein after
457 * this page in a single I/O.
459 VM_OBJECT_RLOCK(obj);
460 if (!vm_pager_has_page(obj, OFF_TO_IDX(vmoff(i, off)), NULL,
462 VM_OBJECT_RUNLOCK(obj);
463 pmap_zero_page(pa[i]);
464 vm_page_valid(pa[i]);
465 MPASS(pa[i]->dirty == 0);
466 vm_page_xunbusy(pa[i]);
470 VM_OBJECT_RUNLOCK(obj);
473 * We want to pagein as many pages as possible, limited only
474 * by the 'a' hint and actual request.
476 count = min(a + 1, npages - i);
479 * We should not pagein into a valid page because
480 * there might be still unfinished write tracked by
481 * e.g. a buffer, thus we substitute any valid pages
482 * with the bogus one.
484 * We must not leave around xbusy pages which are not
485 * part of the run passed to vm_pager_getpages(),
486 * otherwise pager might deadlock waiting for the busy
487 * status of the page, e.g. if it constitues the
488 * buffer needed to validate other page.
490 * First trim the end of the run consisting of the
491 * valid pages, then replace the rest of the valid
495 for (j = i + count - 1; j > i; j--) {
496 if (vm_page_is_valid(pa[j], vmoff(j, off) & PAGE_MASK,
497 xfsize(j, npages, off, len))) {
498 vm_page_xunbusy(pa[j]);
499 SFSTAT_INC(sf_pages_valid);
507 * The last page in the run pa[i + count - 1] is
508 * guaranteed to be invalid by the trim above, so it
509 * is not replaced with bogus, thus -1 in the loop end
512 MPASS(pa[i + count - 1]->valid != VM_PAGE_BITS_ALL);
513 for (j = i + 1; j < i + count - 1; j++) {
514 if (vm_page_is_valid(pa[j], vmoff(j, off) & PAGE_MASK,
515 xfsize(j, npages, off, len))) {
516 vm_page_xunbusy(pa[j]);
517 SFSTAT_INC(sf_pages_valid);
518 SFSTAT_INC(sf_pages_bogus);
523 refcount_acquire(&sfio->nios);
524 rv = vm_pager_get_pages_async(obj, pa + i, count, NULL,
525 i + count == npages ? &rhpages : NULL,
526 &sendfile_iodone, sfio);
527 if (__predict_false(rv != VM_PAGER_OK)) {
528 sendfile_iowait(sfio, "sferrio");
531 * Do remaining pages recovery before returning EIO.
532 * Pages from 0 to npages are wired.
533 * Pages from (i + count1) to npages are busied.
535 for (j = 0; j < npages; j++) {
537 vm_page_xunbusy(pa[j]);
538 KASSERT(pa[j] != NULL && pa[j] != bogus_page,
539 ("%s: page %p[%d] I/O recovery failure",
541 vm_page_unwire(pa[j], PQ_INACTIVE);
547 SFSTAT_INC(sf_iocnt);
548 SFSTAT_ADD(sf_pages_read, count);
549 if (i + count == npages)
550 SFSTAT_ADD(sf_rhpages_read, rhpages);
556 if (*nios == 0 && npages != 0)
557 SFSTAT_INC(sf_noiocnt);
563 sendfile_getobj(struct thread *td, struct file *fp, vm_object_t *obj_res,
564 struct vnode **vp_res, struct shmfd **shmfd_res, off_t *obj_size,
575 shmfd = *shmfd_res = NULL;
579 * The file descriptor must be a regular file and have a
582 if (fp->f_type == DTYPE_VNODE) {
584 vn_lock(vp, LK_SHARED | LK_RETRY);
585 if (vp->v_type != VREG) {
589 *bsize = vp->v_mount->mnt_stat.f_iosize;
597 * Use the pager size when available to simplify synchronization
598 * with filesystems, which otherwise must atomically update both
599 * the vnode pager size and file size.
601 if (obj->type == OBJT_VNODE) {
602 VM_OBJECT_RLOCK(obj);
603 *obj_size = obj->un_pager.vnp.vnp_size;
605 error = vn_getsize_locked(vp, obj_size, td->td_ucred);
608 VM_OBJECT_RLOCK(obj);
610 } else if (fp->f_type == DTYPE_SHM) {
612 obj = shmfd->shm_object;
613 VM_OBJECT_RLOCK(obj);
614 *obj_size = shmfd->shm_size;
620 if ((obj->flags & OBJ_DEAD) != 0) {
621 VM_OBJECT_RUNLOCK(obj);
627 * Temporarily increase the backing VM object's reference
628 * count so that a forced reclamation of its vnode does not
629 * immediately destroy it.
631 vm_object_reference_locked(obj);
632 VM_OBJECT_RUNLOCK(obj);
644 sendfile_getsock(struct thread *td, int s, struct file **sock_fp,
653 * The socket must be a stream socket and connected.
655 error = getsock(td, s, &cap_send_rights, sock_fp);
658 *so = (*sock_fp)->f_data;
659 if ((*so)->so_type != SOCK_STREAM)
662 * SCTP one-to-one style sockets currently don't work with
663 * sendfile(). So indicate EINVAL for now.
665 if ((*so)->so_proto->pr_protocol == IPPROTO_SCTP)
671 vn_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio,
672 struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags,
675 struct file *sock_fp;
677 struct vm_object *obj;
681 struct ktls_session *tls;
683 struct mbuf *m, *mh, *mhtail;
686 struct sendfile_sync *sfs;
688 off_t off, sbytes, rem, obj_size, nobj_size;
689 int bsize, error, ext_pgs_idx, hdrlen, max_pgs, softerr;
706 error = sendfile_getobj(td, fp, &obj, &vp, &shmfd, &obj_size, &bsize);
710 error = sendfile_getsock(td, sockfd, &sock_fp, &so);
715 error = mac_socket_check_send(td->td_ucred, so);
720 SFSTAT_INC(sf_syscalls);
721 SFSTAT_ADD(sf_rhpages_requested, SF_READAHEAD(flags));
723 if (flags & SF_SYNC) {
724 sfs = malloc(sizeof(*sfs), M_SENDFILE, M_WAITOK | M_ZERO);
725 mtx_init(&sfs->mtx, "sendfile", NULL, MTX_DEF);
726 cv_init(&sfs->cv, "sendfile");
730 rem = nbytes ? omin(nbytes, obj_size - offset) : obj_size - offset;
733 * Protect against multiple writers to the socket.
735 * XXXRW: Historically this has assumed non-interruptibility, so now
736 * we implement that, but possibly shouldn't.
738 error = SOCK_IO_SEND_LOCK(so, SBL_WAIT | SBL_NOINTR);
742 tls = ktls_hold(so->so_snd.sb_tls_info);
746 * Loop through the pages of the file, starting with the requested
747 * offset. Get a file page (do I/O if necessary), map the file page
748 * into an sf_buf, attach an mbuf header to the sf_buf, and queue
750 * This is done in two loops. The inner loop turns as many pages
751 * as it can, up to available socket buffer space, without blocking
752 * into mbufs to have it bulk delivered into the socket send buffer.
753 * The outer loop checks the state and available space of the socket
754 * and takes care of the overall progress.
756 for (off = offset; rem > 0; ) {
759 struct mbuf *m0, *mtail;
760 int nios, space, npages, rhpages;
764 * Check the socket state for ongoing connection,
765 * no errors and space in socket buffer.
766 * If space is low allow for the remainder of the
767 * file to be processed if it fits the socket buffer.
768 * Otherwise block in waiting for sufficient space
769 * to proceed, or if the socket is nonblocking, return
770 * to userland with EAGAIN while reporting how far
772 * We wait until the socket buffer has significant free
773 * space to do bulk sends. This makes good use of file
774 * system read ahead and allows packet segmentation
775 * offloading hardware to take over lots of work. If
776 * we were not careful here we would send off only one
779 SOCKBUF_LOCK(&so->so_snd);
780 if (so->so_snd.sb_lowat < so->so_snd.sb_hiwat / 2)
781 so->so_snd.sb_lowat = so->so_snd.sb_hiwat / 2;
783 if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
785 SOCKBUF_UNLOCK(&so->so_snd);
787 } else if (so->so_error) {
788 error = so->so_error;
790 SOCKBUF_UNLOCK(&so->so_snd);
793 if ((so->so_state & SS_ISCONNECTED) == 0) {
794 SOCKBUF_UNLOCK(&so->so_snd);
799 space = sbspace(&so->so_snd);
802 space < so->so_snd.sb_lowat)) {
803 if (so->so_state & SS_NBIO) {
804 SOCKBUF_UNLOCK(&so->so_snd);
809 * sbwait drops the lock while sleeping.
810 * When we loop back to retry_space the
811 * state may have changed and we retest
814 error = sbwait(so, SO_SND);
816 * An error from sbwait usually indicates that we've
817 * been interrupted by a signal. If we've sent anything
818 * then return bytes sent, otherwise return the error.
821 SOCKBUF_UNLOCK(&so->so_snd);
826 SOCKBUF_UNLOCK(&so->so_snd);
829 * At the beginning of the first loop check if any headers
830 * are specified and copy them into mbufs. Reduce space in
831 * the socket buffer by the size of the header mbuf chain.
832 * Clear hdr_uio here and hdrlen at the end of the first loop.
834 if (hdr_uio != NULL && hdr_uio->uio_resid > 0) {
835 hdr_uio->uio_td = td;
836 hdr_uio->uio_rw = UIO_WRITE;
839 mh = m_uiotombuf(hdr_uio, M_WAITOK, space,
840 tls->params.max_frame_len, M_EXTPG);
843 mh = m_uiotombuf(hdr_uio, M_WAITOK,
845 hdrlen = m_length(mh, &mhtail);
848 * If header consumed all the socket buffer space,
849 * don't waste CPU cycles and jump to the end.
860 error = vn_lock(vp, LK_SHARED);
865 * Check to see if the file size has changed.
867 if (obj->type == OBJT_VNODE) {
868 VM_OBJECT_RLOCK(obj);
869 nobj_size = obj->un_pager.vnp.vnp_size;
870 VM_OBJECT_RUNLOCK(obj);
872 error = VOP_GETATTR(vp, &va, td->td_ucred);
877 nobj_size = va.va_size;
879 if (off >= nobj_size) {
883 if (nobj_size != obj_size) {
884 obj_size = nobj_size;
885 rem = nbytes ? omin(nbytes + offset, obj_size) :
893 else if (space > PAGE_SIZE) {
895 * Use page boundaries when possible for large
899 space -= (PAGE_SIZE - (off & PAGE_MASK));
900 space = trunc_page(space);
902 space += (PAGE_SIZE - (off & PAGE_MASK));
905 npages = howmany(space + (off & PAGE_MASK), PAGE_SIZE);
908 * Calculate maximum allowed number of pages for readahead
909 * at this iteration. If SF_USER_READAHEAD was set, we don't
910 * do any heuristics and use exactly the value supplied by
911 * application. Otherwise, we allow readahead up to "rem".
912 * If application wants more, let it be, but there is no
913 * reason to go above maxphys. Also check against "obj_size",
914 * since vm_pager_has_page() can hint beyond EOF.
916 if (flags & SF_USER_READAHEAD) {
917 rhpages = SF_READAHEAD(flags);
919 rhpages = howmany(rem + (off & PAGE_MASK), PAGE_SIZE) -
921 rhpages += SF_READAHEAD(flags);
923 rhpages = min(howmany(maxphys, PAGE_SIZE), rhpages);
924 rhpages = min(howmany(obj_size - trunc_page(off), PAGE_SIZE) -
927 sfio = malloc(sizeof(struct sf_io) +
928 npages * sizeof(vm_page_t), M_SENDFILE, M_WAITOK);
929 refcount_init(&sfio->nios, 1);
933 sfio->npages = npages;
936 * This doesn't use ktls_hold() because sfio->m will
937 * also have a reference on 'tls' that will be valid
938 * for all of sfio's lifetime.
942 vm_object_pip_add(obj, 1);
943 error = sendfile_swapin(obj, sfio, &nios, off, space, rhpages,
948 sendfile_iodone(sfio, NULL, 0, error);
953 * Loop and construct maximum sized mbuf chain to be bulk
954 * dumped into socket buffer.
959 * Use unmapped mbufs if enabled for TCP. Unmapped
960 * bufs are restricted to TCP as that is what has been
961 * tested. In particular, unmapped mbufs have not
962 * been tested with UNIX-domain sockets.
964 * TLS frames always require unmapped mbufs.
966 if ((mb_use_ext_pgs &&
967 so->so_proto->pr_protocol == IPPROTO_TCP)
975 max_pgs = num_pages(tls->params.max_frame_len);
978 max_pgs = MBUF_PEXT_MAX_PGS;
980 /* Start at last index, to wrap on first use. */
981 ext_pgs_idx = max_pgs - 1;
984 for (int i = 0; i < npages; i++) {
986 * If a page wasn't grabbed successfully, then
987 * trim the array. Can happen only with SF_NODISKIO.
991 fixspace(npages, i, off, &space);
997 if (pga == bogus_page)
998 pga = vm_page_relookup(obj, sfio->pindex0 + i);
1004 if (ext_pgs_idx == max_pgs) {
1005 m0 = mb_alloc_ext_pgs(M_WAITOK,
1006 sendfile_free_mext_pg);
1008 if (flags & SF_NOCACHE) {
1009 m0->m_ext.ext_flags |=
1013 * See comment below regarding
1014 * ignoring SF_NOCACHE for the
1017 if ((npages - i <= max_pgs) &&
1018 ((off + space) & PAGE_MASK) &&
1019 (rem > space || rhpages > 0))
1020 m0->m_ext.ext_flags |=
1021 EXT_FLAG_CACHE_LAST;
1024 m0->m_ext.ext_flags |=
1026 m0->m_ext.ext_arg1 = sfs;
1027 mtx_lock(&sfs->mtx);
1029 mtx_unlock(&sfs->mtx);
1033 /* Append to mbuf chain. */
1040 vmoff(i, off) & PAGE_MASK;
1043 mtail->m_flags |= M_NOTREADY;
1047 m0->m_epg_pa[ext_pgs_idx] = VM_PAGE_TO_PHYS(pga);
1049 xfs = xfsize(i, npages, off, space);
1050 m0->m_epg_last_len = xfs;
1051 MBUF_EXT_PGS_ASSERT_SANITY(m0);
1052 mtail->m_len += xfs;
1053 mtail->m_ext.ext_size += PAGE_SIZE;
1058 * Get a sendfile buf. When allocating the
1059 * first buffer for mbuf chain, we usually
1060 * wait as long as necessary, but this wait
1061 * can be interrupted. For consequent
1062 * buffers, do not sleep, since several
1063 * threads might exhaust the buffers and then
1066 sf = sf_buf_alloc(pga,
1067 m != NULL ? SFB_NOWAIT : SFB_CATCH);
1069 SFSTAT_INC(sf_allocfail);
1070 sendfile_iowait(sfio, "sfnosf");
1071 for (int j = i; j < npages; j++) {
1072 vm_page_unwire(pa[j], PQ_INACTIVE);
1077 fixspace(npages, i, off, &space);
1082 m0 = m_get(M_WAITOK, MT_DATA);
1083 m0->m_ext.ext_buf = (char *)sf_buf_kva(sf);
1084 m0->m_ext.ext_size = PAGE_SIZE;
1085 m0->m_ext.ext_arg1 = sf;
1086 m0->m_ext.ext_type = EXT_SFBUF;
1087 m0->m_ext.ext_flags = EXT_FLAG_EMBREF;
1088 m0->m_ext.ext_free = sendfile_free_mext;
1090 * SF_NOCACHE sets the page as being freed upon send.
1091 * However, we ignore it for the last page in 'space',
1092 * if the page is truncated, and we got more data to
1093 * send (rem > space), or if we have readahead
1094 * configured (rhpages > 0).
1096 if ((flags & SF_NOCACHE) &&
1098 !((off + space) & PAGE_MASK) ||
1099 !(rem > space || rhpages > 0)))
1100 m0->m_ext.ext_flags |= EXT_FLAG_NOCACHE;
1102 m0->m_ext.ext_flags |= EXT_FLAG_SYNC;
1103 m0->m_ext.ext_arg2 = sfs;
1104 mtx_lock(&sfs->mtx);
1106 mtx_unlock(&sfs->mtx);
1108 m0->m_ext.ext_count = 1;
1109 m0->m_flags |= (M_EXT | M_RDONLY);
1111 m0->m_flags |= M_NOTREADY;
1112 m0->m_data = (char *)sf_buf_kva(sf) +
1113 (vmoff(i, off) & PAGE_MASK);
1114 m0->m_len = xfsize(i, npages, off, space);
1116 /* Append to mbuf chain. */
1127 /* Keep track of bytes processed. */
1132 * Prepend header, if any. Save pointer to first mbuf
1137 m0 = mhtail->m_next = m;
1144 KASSERT(softerr, ("%s: m NULL, no error", __func__));
1146 sendfile_iodone(sfio, NULL, 0, 0);
1150 /* Add the buffer chain to the socket buffer. */
1151 KASSERT(m_length(m, NULL) == space + hdrlen,
1152 ("%s: mlen %u space %d hdrlen %d",
1153 __func__, m_length(m, NULL), space, hdrlen));
1155 CURVNET_SET(so->so_vnet);
1158 ktls_frame(m, tls, &tls_enq_cnt, TLS_RLTYPE_APP);
1162 * If sendfile_swapin() didn't initiate any I/Os,
1163 * which happens if all data is cached in VM, or if
1164 * the header consumed all socket buffer space and
1165 * sfio is NULL, then we can send data right now
1166 * without the PRUS_NOTREADY flag.
1169 sendfile_iodone(sfio, NULL, 0, 0);
1171 if (tls != NULL && tls->mode == TCP_TLS_MODE_SW) {
1172 error = so->so_proto->pr_send(so,
1173 PRUS_NOTREADY, m, NULL, NULL, td);
1178 ktls_enqueue(m, so, tls_enq_cnt);
1182 error = so->so_proto->pr_send(so, 0, m, NULL,
1188 error = so->so_proto->pr_send(so, PRUS_NOTREADY, m,
1190 sendfile_iodone(sfio, NULL, 0, error);
1192 #ifdef TCP_REQUEST_TRK
1193 if (so->so_proto->pr_protocol == IPPROTO_TCP) {
1194 /* log the sendfile call to the TCP log, if enabled */
1195 tcp_log_sendfile(so, offset, nbytes, flags);
1203 sbytes += space + hdrlen;
1213 * Send trailers. Wimp out and use writev(2).
1215 if (trl_uio != NULL) {
1216 SOCK_IO_SEND_UNLOCK(so);
1217 error = kern_writev(td, sockfd, trl_uio);
1219 sbytes += td->td_retval[0];
1224 SOCK_IO_SEND_UNLOCK(so);
1227 * If there was no error we have to clear td->td_retval[0]
1228 * because it may have been set by writev.
1231 td->td_retval[0] = 0;
1237 vm_object_deallocate(obj);
1246 mtx_lock(&sfs->mtx);
1247 if (sfs->count != 0)
1248 error = cv_wait_sig(&sfs->cv, &sfs->mtx);
1249 if (sfs->count == 0) {
1250 sendfile_sync_destroy(sfs);
1252 sfs->waiting = false;
1253 mtx_unlock(&sfs->mtx);
1261 if (error == ERESTART)
1268 sendfile(struct thread *td, struct sendfile_args *uap, int compat)
1270 struct sf_hdtr hdtr;
1271 struct uio *hdr_uio, *trl_uio;
1277 * File offset must be positive. If it goes beyond EOF
1278 * we send only the header/trailer and no payload data.
1280 if (uap->offset < 0)
1284 hdr_uio = trl_uio = NULL;
1286 if (uap->hdtr != NULL) {
1287 error = copyin(uap->hdtr, &hdtr, sizeof(hdtr));
1290 if (hdtr.headers != NULL) {
1291 error = copyinuio(hdtr.headers, hdtr.hdr_cnt,
1295 #ifdef COMPAT_FREEBSD4
1297 * In FreeBSD < 5.0 the nbytes to send also included
1298 * the header. If compat is specified subtract the
1299 * header size from nbytes.
1302 if (uap->nbytes > hdr_uio->uio_resid)
1303 uap->nbytes -= hdr_uio->uio_resid;
1309 if (hdtr.trailers != NULL) {
1310 error = copyinuio(hdtr.trailers, hdtr.trl_cnt,
1317 AUDIT_ARG_FD(uap->fd);
1320 * sendfile(2) can start at any offset within a file so we require
1321 * CAP_READ+CAP_SEEK = CAP_PREAD.
1323 if ((error = fget_read(td, uap->fd, &cap_pread_rights, &fp)) != 0)
1326 error = fo_sendfile(fp, uap->s, hdr_uio, trl_uio, uap->offset,
1327 uap->nbytes, &sbytes, uap->flags, td);
1330 if (uap->sbytes != NULL)
1331 (void)copyout(&sbytes, uap->sbytes, sizeof(off_t));
1342 * int sendfile(int fd, int s, off_t offset, size_t nbytes,
1343 * struct sf_hdtr *hdtr, off_t *sbytes, int flags)
1345 * Send a file specified by 'fd' and starting at 'offset' to a socket
1346 * specified by 's'. Send only 'nbytes' of the file or until EOF if nbytes ==
1347 * 0. Optionally add a header and/or trailer to the socket output. If
1348 * specified, write the total number of bytes sent into *sbytes.
1351 sys_sendfile(struct thread *td, struct sendfile_args *uap)
1354 return (sendfile(td, uap, 0));
1357 #ifdef COMPAT_FREEBSD4
1359 freebsd4_sendfile(struct thread *td, struct freebsd4_sendfile_args *uap)
1361 struct sendfile_args args;
1365 args.offset = uap->offset;
1366 args.nbytes = uap->nbytes;
1367 args.hdtr = uap->hdtr;
1368 args.sbytes = uap->sbytes;
1369 args.flags = uap->flags;
1371 return (sendfile(td, &args, 1));
1373 #endif /* COMPAT_FREEBSD4 */