/*- * Copyright (c) 2013-2015 Gleb Smirnoff * Copyright (c) 1998, David Greenman. 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, 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. * 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. */ #include __FBSDID("$FreeBSD$"); #include "opt_compat.h" #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 /* * Structure describing a single sendfile(2) I/O, which may consist of * several underlying pager I/Os. * * The syscall context allocates the structure and initializes 'nios' * to 1. As sendfile_swapin() runs through pages and starts asynchronous * paging operations, it increments 'nios'. * * Every I/O completion calls sendfile_iodone(), which decrements the 'nios', * and the syscall also calls sendfile_iodone() after allocating all mbufs, * linking them and sending to socket. Whoever reaches zero 'nios' is * responsible to * call pru_ready on the socket, to notify it of readyness * of the data. */ struct sf_io { volatile u_int nios; u_int error; int npages; struct file *sock_fp; struct mbuf *m; vm_page_t pa[]; }; /* * Structure used to track requests with SF_SYNC flag. */ struct sendfile_sync { struct mtx mtx; struct cv cv; unsigned count; }; counter_u64_t sfstat[sizeof(struct sfstat) / sizeof(uint64_t)]; static void sfstat_init(const void *unused) { COUNTER_ARRAY_ALLOC(sfstat, sizeof(struct sfstat) / sizeof(uint64_t), M_WAITOK); } SYSINIT(sfstat, SI_SUB_MBUF, SI_ORDER_FIRST, sfstat_init, NULL); static int sfstat_sysctl(SYSCTL_HANDLER_ARGS) { struct sfstat s; COUNTER_ARRAY_COPY(sfstat, &s, sizeof(s) / sizeof(uint64_t)); if (req->newptr) COUNTER_ARRAY_ZERO(sfstat, sizeof(s) / sizeof(uint64_t)); return (SYSCTL_OUT(req, &s, sizeof(s))); } SYSCTL_PROC(_kern_ipc, OID_AUTO, sfstat, CTLTYPE_OPAQUE | CTLFLAG_RW, NULL, 0, sfstat_sysctl, "I", "sendfile statistics"); /* * Detach mapped page and release resources back to the system. Called * by mbuf(9) code when last reference to a page is freed. */ void sf_ext_free(void *arg1, void *arg2) { struct sf_buf *sf = arg1; struct sendfile_sync *sfs = arg2; vm_page_t pg = sf_buf_page(sf); sf_buf_free(sf); vm_page_lock(pg); /* * Check for the object going away on us. This can * happen since we don't hold a reference to it. * If so, we're responsible for freeing the page. */ if (vm_page_unwire(pg, PQ_INACTIVE) && pg->object == NULL) vm_page_free(pg); vm_page_unlock(pg); if (sfs != NULL) { mtx_lock(&sfs->mtx); KASSERT(sfs->count > 0, ("Sendfile sync botchup count == 0")); if (--sfs->count == 0) cv_signal(&sfs->cv); mtx_unlock(&sfs->mtx); } } /* * Same as above, but forces the page to be detached from the object * and go into free pool. */ void sf_ext_free_nocache(void *arg1, void *arg2) { struct sf_buf *sf = arg1; struct sendfile_sync *sfs = arg2; vm_page_t pg = sf_buf_page(sf); sf_buf_free(sf); vm_page_lock(pg); if (vm_page_unwire(pg, PQ_NONE)) { vm_object_t obj; /* Try to free the page, but only if it is cheap to. */ if ((obj = pg->object) == NULL) vm_page_free(pg); else if (!vm_page_xbusied(pg) && VM_OBJECT_TRYWLOCK(obj)) { vm_page_free(pg); VM_OBJECT_WUNLOCK(obj); } else vm_page_deactivate(pg); } vm_page_unlock(pg); if (sfs != NULL) { mtx_lock(&sfs->mtx); KASSERT(sfs->count > 0, ("Sendfile sync botchup count == 0")); if (--sfs->count == 0) cv_signal(&sfs->cv); mtx_unlock(&sfs->mtx); } } /* * Helper function to calculate how much data to put into page i of n. * Only first and last pages are special. */ static inline off_t xfsize(int i, int n, off_t off, off_t len) { if (i == 0) return (omin(PAGE_SIZE - (off & PAGE_MASK), len)); if (i == n - 1 && ((off + len) & PAGE_MASK) > 0) return ((off + len) & PAGE_MASK); return (PAGE_SIZE); } /* * Helper function to get offset within object for i page. */ static inline vm_offset_t vmoff(int i, off_t off) { if (i == 0) return ((vm_offset_t)off); return (trunc_page(off + i * PAGE_SIZE)); } /* * Helper function used when allocation of a page or sf_buf failed. * Pretend as if we don't have enough space, subtract xfsize() of * all pages that failed. */ static inline void fixspace(int old, int new, off_t off, int *space) { KASSERT(old > new, ("%s: old %d new %d", __func__, old, new)); /* Subtract last one. */ *space -= xfsize(old - 1, old, off, *space); old--; if (new == old) /* There was only one page. */ return; /* Subtract first one. */ if (new == 0) { *space -= xfsize(0, old, off, *space); new++; } /* Rest of pages are full sized. */ *space -= (old - new) * PAGE_SIZE; KASSERT(*space >= 0, ("%s: space went backwards", __func__)); } /* * I/O completion callback. */ static void sendfile_iodone(void *arg, vm_page_t *pg, int count, int error) { struct sf_io *sfio = arg; struct socket *so; for (int i = 0; i < count; i++) vm_page_xunbusy(pg[i]); if (error) sfio->error = error; if (!refcount_release(&sfio->nios)) return; so = sfio->sock_fp->f_data; if (sfio->error) { struct mbuf *m; /* * I/O operation failed. The state of data in the socket * is now inconsistent, and all what we can do is to tear * it down. Protocol abort method would tear down protocol * state, free all ready mbufs and detach not ready ones. * We will free the mbufs corresponding to this I/O manually. * * The socket would be marked with EIO and made available * for read, so that application receives EIO on next * syscall and eventually closes the socket. */ so->so_proto->pr_usrreqs->pru_abort(so); so->so_error = EIO; m = sfio->m; for (int i = 0; i < sfio->npages; i++) m = m_free(m); } else { CURVNET_SET(so->so_vnet); (void )(so->so_proto->pr_usrreqs->pru_ready)(so, sfio->m, sfio->npages); CURVNET_RESTORE(); } /* XXXGL: curthread */ fdrop(sfio->sock_fp, curthread); free(sfio, M_TEMP); } /* * Iterate through pages vector and request paging for non-valid pages. */ static int sendfile_swapin(vm_object_t obj, struct sf_io *sfio, off_t off, off_t len, int npages, int rhpages, int flags) { vm_page_t *pa = sfio->pa; int nios; nios = 0; flags = (flags & SF_NODISKIO) ? VM_ALLOC_NOWAIT : 0; /* * First grab all the pages and wire them. Note that we grab * only required pages. Readahead pages are dealt with later. */ VM_OBJECT_WLOCK(obj); for (int i = 0; i < npages; i++) { pa[i] = vm_page_grab(obj, OFF_TO_IDX(vmoff(i, off)), VM_ALLOC_WIRED | VM_ALLOC_NORMAL | flags); if (pa[i] == NULL) { npages = i; rhpages = 0; break; } } for (int i = 0; i < npages;) { int j, a, count, rv; /* Skip valid pages. */ if (vm_page_is_valid(pa[i], vmoff(i, off) & PAGE_MASK, xfsize(i, npages, off, len))) { vm_page_xunbusy(pa[i]); SFSTAT_INC(sf_pages_valid); i++; continue; } /* * Now 'i' points to first invalid page, iterate further * to make 'j' point at first valid after a bunch of * invalid ones. */ for (j = i + 1; j < npages; j++) if (vm_page_is_valid(pa[j], vmoff(j, off) & PAGE_MASK, xfsize(j, npages, off, len))) { SFSTAT_INC(sf_pages_valid); break; } /* * Now we got region of invalid pages between 'i' and 'j'. * Check that they belong to pager. They may not be there, * which is a regular situation for shmem pager. For vnode * pager this happens only in case of sparse file. * * Important feature of vm_pager_has_page() is the hint * stored in 'a', about how many pages we can pagein after * this page in a single I/O. */ while (!vm_pager_has_page(obj, OFF_TO_IDX(vmoff(i, off)), NULL, &a) && i < j) { pmap_zero_page(pa[i]); pa[i]->valid = VM_PAGE_BITS_ALL; pa[i]->dirty = 0; vm_page_xunbusy(pa[i]); i++; } if (i == j) continue; /* * We want to pagein as many pages as possible, limited only * by the 'a' hint and actual request. * * We should not pagein into already valid page, thus if * 'j' didn't reach last page, trim by that page. * * When the pagein fulfils the request, also specify readahead. */ if (j < npages) a = min(a, j - i - 1); count = min(a + 1, npages - i); refcount_acquire(&sfio->nios); rv = vm_pager_get_pages_async(obj, pa + i, count, NULL, i + count == npages ? &rhpages : NULL, &sendfile_iodone, sfio); KASSERT(rv == VM_PAGER_OK, ("%s: pager fail obj %p page %p", __func__, obj, pa[i])); SFSTAT_INC(sf_iocnt); SFSTAT_ADD(sf_pages_read, count); if (i + count == npages) SFSTAT_ADD(sf_rhpages_read, rhpages); #ifdef INVARIANTS for (j = i; j < i + count && j < npages; j++) KASSERT(pa[j] == vm_page_lookup(obj, OFF_TO_IDX(vmoff(j, off))), ("pa[j] %p lookup %p\n", pa[j], vm_page_lookup(obj, OFF_TO_IDX(vmoff(j, off))))); #endif i += count; nios++; } VM_OBJECT_WUNLOCK(obj); if (nios == 0 && npages != 0) SFSTAT_INC(sf_noiocnt); return (nios); } static int sendfile_getobj(struct thread *td, struct file *fp, vm_object_t *obj_res, struct vnode **vp_res, struct shmfd **shmfd_res, off_t *obj_size, int *bsize) { struct vattr va; vm_object_t obj; struct vnode *vp; struct shmfd *shmfd; int error; vp = *vp_res = NULL; obj = NULL; shmfd = *shmfd_res = NULL; *bsize = 0; /* * The file descriptor must be a regular file and have a * backing VM object. */ if (fp->f_type == DTYPE_VNODE) { vp = fp->f_vnode; vn_lock(vp, LK_SHARED | LK_RETRY); if (vp->v_type != VREG) { error = EINVAL; goto out; } *bsize = vp->v_mount->mnt_stat.f_iosize; error = VOP_GETATTR(vp, &va, td->td_ucred); if (error != 0) goto out; *obj_size = va.va_size; obj = vp->v_object; if (obj == NULL) { error = EINVAL; goto out; } } else if (fp->f_type == DTYPE_SHM) { error = 0; shmfd = fp->f_data; obj = shmfd->shm_object; *obj_size = shmfd->shm_size; } else { error = EINVAL; goto out; } VM_OBJECT_WLOCK(obj); if ((obj->flags & OBJ_DEAD) != 0) { VM_OBJECT_WUNLOCK(obj); error = EBADF; goto out; } /* * Temporarily increase the backing VM object's reference * count so that a forced reclamation of its vnode does not * immediately destroy it. */ vm_object_reference_locked(obj); VM_OBJECT_WUNLOCK(obj); *obj_res = obj; *vp_res = vp; *shmfd_res = shmfd; out: if (vp != NULL) VOP_UNLOCK(vp, 0); return (error); } static int sendfile_getsock(struct thread *td, int s, struct file **sock_fp, struct socket **so) { cap_rights_t rights; int error; *sock_fp = NULL; *so = NULL; /* * The socket must be a stream socket and connected. */ error = getsock_cap(td, s, cap_rights_init(&rights, CAP_SEND), sock_fp, NULL); if (error != 0) return (error); *so = (*sock_fp)->f_data; if ((*so)->so_type != SOCK_STREAM) return (EINVAL); if (((*so)->so_state & SS_ISCONNECTED) == 0) return (ENOTCONN); return (0); } int vn_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, int kflags, struct thread *td) { struct file *sock_fp; struct vnode *vp; struct vm_object *obj; struct socket *so; struct mbuf *m, *mh, *mhtail; struct sf_buf *sf; struct shmfd *shmfd; struct sendfile_sync *sfs; struct vattr va; off_t off, sbytes, rem, obj_size; int error, softerr, bsize, hdrlen; obj = NULL; so = NULL; m = mh = NULL; sfs = NULL; sbytes = 0; softerr = 0; error = sendfile_getobj(td, fp, &obj, &vp, &shmfd, &obj_size, &bsize); if (error != 0) return (error); error = sendfile_getsock(td, sockfd, &sock_fp, &so); if (error != 0) goto out; #ifdef MAC error = mac_socket_check_send(td->td_ucred, so); if (error != 0) goto out; #endif SFSTAT_INC(sf_syscalls); SFSTAT_ADD(sf_rhpages_requested, SF_READAHEAD(flags)); if (flags & SF_SYNC) { sfs = malloc(sizeof *sfs, M_TEMP, M_WAITOK | M_ZERO); mtx_init(&sfs->mtx, "sendfile", NULL, MTX_DEF); cv_init(&sfs->cv, "sendfile"); } /* If headers are specified copy them into mbufs. */ if (hdr_uio != NULL && hdr_uio->uio_resid > 0) { hdr_uio->uio_td = td; hdr_uio->uio_rw = UIO_WRITE; /* * In FBSD < 5.0 the nbytes to send also included * the header. If compat is specified subtract the * header size from nbytes. */ if (kflags & SFK_COMPAT) { if (nbytes > hdr_uio->uio_resid) nbytes -= hdr_uio->uio_resid; else nbytes = 0; } mh = m_uiotombuf(hdr_uio, M_WAITOK, 0, 0, 0); hdrlen = m_length(mh, &mhtail); } else hdrlen = 0; rem = nbytes ? omin(nbytes, obj_size - offset) : obj_size - offset; /* * Protect against multiple writers to the socket. * * XXXRW: Historically this has assumed non-interruptibility, so now * we implement that, but possibly shouldn't. */ (void)sblock(&so->so_snd, SBL_WAIT | SBL_NOINTR); /* * Loop through the pages of the file, starting with the requested * offset. Get a file page (do I/O if necessary), map the file page * into an sf_buf, attach an mbuf header to the sf_buf, and queue * it on the socket. * This is done in two loops. The inner loop turns as many pages * as it can, up to available socket buffer space, without blocking * into mbufs to have it bulk delivered into the socket send buffer. * The outer loop checks the state and available space of the socket * and takes care of the overall progress. */ for (off = offset; rem > 0; ) { struct sf_io *sfio; vm_page_t *pa; struct mbuf *mtail; int nios, space, npages, rhpages; mtail = NULL; /* * Check the socket state for ongoing connection, * no errors and space in socket buffer. * If space is low allow for the remainder of the * file to be processed if it fits the socket buffer. * Otherwise block in waiting for sufficient space * to proceed, or if the socket is nonblocking, return * to userland with EAGAIN while reporting how far * we've come. * We wait until the socket buffer has significant free * space to do bulk sends. This makes good use of file * system read ahead and allows packet segmentation * offloading hardware to take over lots of work. If * we were not careful here we would send off only one * sfbuf at a time. */ SOCKBUF_LOCK(&so->so_snd); if (so->so_snd.sb_lowat < so->so_snd.sb_hiwat / 2) so->so_snd.sb_lowat = so->so_snd.sb_hiwat / 2; retry_space: if (so->so_snd.sb_state & SBS_CANTSENDMORE) { error = EPIPE; SOCKBUF_UNLOCK(&so->so_snd); goto done; } else if (so->so_error) { error = so->so_error; so->so_error = 0; SOCKBUF_UNLOCK(&so->so_snd); goto done; } space = sbspace(&so->so_snd); if (space < rem && (space <= 0 || space < so->so_snd.sb_lowat)) { if (so->so_state & SS_NBIO) { SOCKBUF_UNLOCK(&so->so_snd); error = EAGAIN; goto done; } /* * sbwait drops the lock while sleeping. * When we loop back to retry_space the * state may have changed and we retest * for it. */ error = sbwait(&so->so_snd); /* * An error from sbwait usually indicates that we've * been interrupted by a signal. If we've sent anything * then return bytes sent, otherwise return the error. */ if (error != 0) { SOCKBUF_UNLOCK(&so->so_snd); goto done; } goto retry_space; } SOCKBUF_UNLOCK(&so->so_snd); /* * Reduce space in the socket buffer by the size of * the header mbuf chain. * hdrlen is set to 0 after the first loop. */ space -= hdrlen; if (vp != NULL) { error = vn_lock(vp, LK_SHARED); if (error != 0) goto done; error = VOP_GETATTR(vp, &va, td->td_ucred); if (error != 0 || off >= va.va_size) { VOP_UNLOCK(vp, 0); goto done; } if (va.va_size != obj_size) { if (nbytes == 0) rem += va.va_size - obj_size; else if (offset + nbytes > va.va_size) rem -= (offset + nbytes - va.va_size); obj_size = va.va_size; } } if (space > rem) space = rem; npages = howmany(space + (off & PAGE_MASK), PAGE_SIZE); /* * Calculate maximum allowed number of pages for readahead * at this iteration. First, we allow readahead up to "rem". * If application wants more, let it be, but there is no * reason to go above MAXPHYS. Also check against "obj_size", * since vm_pager_has_page() can hint beyond EOF. */ rhpages = howmany(rem + (off & PAGE_MASK), PAGE_SIZE) - npages; rhpages += SF_READAHEAD(flags); rhpages = min(howmany(MAXPHYS, PAGE_SIZE), rhpages); rhpages = min(howmany(obj_size - trunc_page(off), PAGE_SIZE) - npages, rhpages); sfio = malloc(sizeof(struct sf_io) + npages * sizeof(vm_page_t), M_TEMP, M_WAITOK); refcount_init(&sfio->nios, 1); sfio->error = 0; nios = sendfile_swapin(obj, sfio, off, space, npages, rhpages, flags); /* * Loop and construct maximum sized mbuf chain to be bulk * dumped into socket buffer. */ pa = sfio->pa; for (int i = 0; i < npages; i++) { struct mbuf *m0; /* * If a page wasn't grabbed successfully, then * trim the array. Can happen only with SF_NODISKIO. */ if (pa[i] == NULL) { SFSTAT_INC(sf_busy); fixspace(npages, i, off, &space); npages = i; softerr = EBUSY; break; } /* * Get a sendfile buf. When allocating the * first buffer for mbuf chain, we usually * wait as long as necessary, but this wait * can be interrupted. For consequent * buffers, do not sleep, since several * threads might exhaust the buffers and then * deadlock. */ sf = sf_buf_alloc(pa[i], m != NULL ? SFB_NOWAIT : SFB_CATCH); if (sf == NULL) { SFSTAT_INC(sf_allocfail); for (int j = i; j < npages; j++) { vm_page_lock(pa[j]); vm_page_unwire(pa[j], PQ_INACTIVE); vm_page_unlock(pa[j]); } if (m == NULL) softerr = ENOBUFS; fixspace(npages, i, off, &space); npages = i; break; } m0 = m_get(M_WAITOK, MT_DATA); m0->m_ext.ext_buf = (char *)sf_buf_kva(sf); m0->m_ext.ext_size = PAGE_SIZE; m0->m_ext.ext_arg1 = sf; m0->m_ext.ext_arg2 = sfs; /* * SF_NOCACHE sets the page as being freed upon send. * However, we ignore it for the last page in 'space', * if the page is truncated, and we got more data to * send (rem > space), or if we have readahead * configured (rhpages > 0). */ if ((flags & SF_NOCACHE) == 0 || (i == npages - 1 && ((off + space) & PAGE_MASK) && (rem > space || rhpages > 0))) m0->m_ext.ext_type = EXT_SFBUF; else m0->m_ext.ext_type = EXT_SFBUF_NOCACHE; m0->m_ext.ext_flags = EXT_FLAG_EMBREF; m0->m_ext.ext_count = 1; m0->m_flags |= (M_EXT | M_RDONLY); if (nios) m0->m_flags |= M_NOTREADY; m0->m_data = (char *)sf_buf_kva(sf) + (vmoff(i, off) & PAGE_MASK); m0->m_len = xfsize(i, npages, off, space); if (i == 0) sfio->m = m0; /* Append to mbuf chain. */ if (mtail != NULL) mtail->m_next = m0; else m = m0; mtail = m0; if (sfs != NULL) { mtx_lock(&sfs->mtx); sfs->count++; mtx_unlock(&sfs->mtx); } } if (vp != NULL) VOP_UNLOCK(vp, 0); /* Keep track of bytes processed. */ off += space; rem -= space; /* Prepend header, if any. */ if (hdrlen) { mhtail->m_next = m; m = mh; mh = NULL; } if (m == NULL) { KASSERT(softerr, ("%s: m NULL, no error", __func__)); error = softerr; free(sfio, M_TEMP); goto done; } /* Add the buffer chain to the socket buffer. */ KASSERT(m_length(m, NULL) == space + hdrlen, ("%s: mlen %u space %d hdrlen %d", __func__, m_length(m, NULL), space, hdrlen)); CURVNET_SET(so->so_vnet); if (nios == 0) { /* * If sendfile_swapin() didn't initiate any I/Os, * which happens if all data is cached in VM, then * we can send data right now without the * PRUS_NOTREADY flag. */ free(sfio, M_TEMP); error = (*so->so_proto->pr_usrreqs->pru_send) (so, 0, m, NULL, NULL, td); } else { sfio->sock_fp = sock_fp; sfio->npages = npages; fhold(sock_fp); error = (*so->so_proto->pr_usrreqs->pru_send) (so, PRUS_NOTREADY, m, NULL, NULL, td); sendfile_iodone(sfio, NULL, 0, 0); } CURVNET_RESTORE(); m = NULL; /* pru_send always consumes */ if (error) goto done; sbytes += space + hdrlen; if (hdrlen) hdrlen = 0; if (softerr) { error = softerr; goto done; } } /* * Send trailers. Wimp out and use writev(2). */ if (trl_uio != NULL) { sbunlock(&so->so_snd); error = kern_writev(td, sockfd, trl_uio); if (error == 0) sbytes += td->td_retval[0]; goto out; } done: sbunlock(&so->so_snd); out: /* * If there was no error we have to clear td->td_retval[0] * because it may have been set by writev. */ if (error == 0) { td->td_retval[0] = 0; } if (sent != NULL) { (*sent) = sbytes; } if (obj != NULL) vm_object_deallocate(obj); if (so) fdrop(sock_fp, td); if (m) m_freem(m); if (mh) m_freem(mh); if (sfs != NULL) { mtx_lock(&sfs->mtx); if (sfs->count != 0) cv_wait(&sfs->cv, &sfs->mtx); KASSERT(sfs->count == 0, ("sendfile sync still busy")); cv_destroy(&sfs->cv); mtx_destroy(&sfs->mtx); free(sfs, M_TEMP); } if (error == ERESTART) error = EINTR; return (error); } static int sendfile(struct thread *td, struct sendfile_args *uap, int compat) { struct sf_hdtr hdtr; struct uio *hdr_uio, *trl_uio; struct file *fp; cap_rights_t rights; off_t sbytes; int error; /* * File offset must be positive. If it goes beyond EOF * we send only the header/trailer and no payload data. */ if (uap->offset < 0) return (EINVAL); hdr_uio = trl_uio = NULL; if (uap->hdtr != NULL) { error = copyin(uap->hdtr, &hdtr, sizeof(hdtr)); if (error != 0) goto out; if (hdtr.headers != NULL) { error = copyinuio(hdtr.headers, hdtr.hdr_cnt, &hdr_uio); if (error != 0) goto out; } if (hdtr.trailers != NULL) { error = copyinuio(hdtr.trailers, hdtr.trl_cnt, &trl_uio); if (error != 0) goto out; } } AUDIT_ARG_FD(uap->fd); /* * sendfile(2) can start at any offset within a file so we require * CAP_READ+CAP_SEEK = CAP_PREAD. */ if ((error = fget_read(td, uap->fd, cap_rights_init(&rights, CAP_PREAD), &fp)) != 0) { goto out; } error = fo_sendfile(fp, uap->s, hdr_uio, trl_uio, uap->offset, uap->nbytes, &sbytes, uap->flags, compat ? SFK_COMPAT : 0, td); fdrop(fp, td); if (uap->sbytes != NULL) copyout(&sbytes, uap->sbytes, sizeof(off_t)); out: free(hdr_uio, M_IOV); free(trl_uio, M_IOV); return (error); } /* * sendfile(2) * * int sendfile(int fd, int s, off_t offset, size_t nbytes, * struct sf_hdtr *hdtr, off_t *sbytes, int flags) * * Send a file specified by 'fd' and starting at 'offset' to a socket * specified by 's'. Send only 'nbytes' of the file or until EOF if nbytes == * 0. Optionally add a header and/or trailer to the socket output. If * specified, write the total number of bytes sent into *sbytes. */ int sys_sendfile(struct thread *td, struct sendfile_args *uap) { return (sendfile(td, uap, 0)); } #ifdef COMPAT_FREEBSD4 int freebsd4_sendfile(struct thread *td, struct freebsd4_sendfile_args *uap) { struct sendfile_args args; args.fd = uap->fd; args.s = uap->s; args.offset = uap->offset; args.nbytes = uap->nbytes; args.hdtr = uap->hdtr; args.sbytes = uap->sbytes; args.flags = uap->flags; return (sendfile(td, &args, 1)); } #endif /* COMPAT_FREEBSD4 */