/* $NetBSD: genfs_vnops.c,v 1.89 2004/10/03 07:59:02 enami Exp $ */ /* * Copyright (c) 1982, 1986, 1989, 1993 * The Regents of the University of California. 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. * 3. 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 __KERNEL_RCSID(0, "$NetBSD: genfs_vnops.c,v 1.89 2004/10/03 07:59:02 enami Exp $"); #include "opt_nfsserver.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef NFSSERVER #include #include #include #include #include #endif static __inline void genfs_rel_pages(struct vm_page **, int); static void filt_genfsdetach(struct knote *); static int filt_genfsread(struct knote *, long); static int filt_genfsvnode(struct knote *, long); #define MAX_READ_AHEAD 16 /* XXXUBC 16 */ int genfs_rapages = MAX_READ_AHEAD; /* # of pages in each chunk of readahead */ int genfs_racount = 2; /* # of page chunks to readahead */ int genfs_raskip = 2; /* # of busy page chunks allowed to skip */ int genfs_poll(void *v) { struct vop_poll_args /* { struct vnode *a_vp; int a_events; struct proc *a_p; } */ *ap = v; return (ap->a_events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM)); } int genfs_fsync(void *v) { struct vop_fsync_args /* { struct vnode *a_vp; struct ucred *a_cred; int a_flags; off_t offlo; off_t offhi; struct proc *a_p; } */ *ap = v; struct vnode *vp = ap->a_vp; int wait; wait = (ap->a_flags & FSYNC_WAIT) != 0; vflushbuf(vp, wait); if ((ap->a_flags & FSYNC_DATAONLY) != 0) return (0); else return (VOP_UPDATE(vp, NULL, NULL, wait ? UPDATE_WAIT : 0)); } int genfs_seek(void *v) { struct vop_seek_args /* { struct vnode *a_vp; off_t a_oldoff; off_t a_newoff; struct ucred *a_ucred; } */ *ap = v; if (ap->a_newoff < 0) return (EINVAL); return (0); } int genfs_abortop(void *v) { struct vop_abortop_args /* { struct vnode *a_dvp; struct componentname *a_cnp; } */ *ap = v; if ((ap->a_cnp->cn_flags & (HASBUF | SAVESTART)) == HASBUF) PNBUF_PUT(ap->a_cnp->cn_pnbuf); return (0); } int genfs_fcntl(void *v) { struct vop_fcntl_args /* { struct vnode *a_vp; u_int a_command; caddr_t a_data; int a_fflag; struct ucred *a_cred; struct proc *a_p; } */ *ap = v; if (ap->a_command == F_SETFL) return (0); else return (EOPNOTSUPP); } /*ARGSUSED*/ int genfs_badop(void *v) { panic("genfs: bad op"); } /*ARGSUSED*/ int genfs_nullop(void *v) { return (0); } /*ARGSUSED*/ int genfs_einval(void *v) { return (EINVAL); } /* * Called when an fs doesn't support a particular vop. * This takes care to vrele, vput, or vunlock passed in vnodes. */ int genfs_eopnotsupp(void *v) { struct vop_generic_args /* struct vnodeop_desc *a_desc; / * other random data follows, presumably * / } */ *ap = v; struct vnodeop_desc *desc = ap->a_desc; struct vnode *vp, *vp_last = NULL; int flags, i, j, offset; flags = desc->vdesc_flags; for (i = 0; i < VDESC_MAX_VPS; flags >>=1, i++) { if ((offset = desc->vdesc_vp_offsets[i]) == VDESC_NO_OFFSET) break; /* stop at end of list */ if ((j = flags & VDESC_VP0_WILLPUT)) { vp = *VOPARG_OFFSETTO(struct vnode **, offset, ap); /* Skip if NULL */ if (!vp) continue; switch (j) { case VDESC_VP0_WILLPUT: /* Check for dvp == vp cases */ if (vp == vp_last) vrele(vp); else { vput(vp); vp_last = vp; } break; case VDESC_VP0_WILLUNLOCK: VOP_UNLOCK(vp, 0); break; case VDESC_VP0_WILLRELE: vrele(vp); break; } } } return (EOPNOTSUPP); } /*ARGSUSED*/ int genfs_ebadf(void *v) { return (EBADF); } /* ARGSUSED */ int genfs_enoioctl(void *v) { return (EPASSTHROUGH); } /* * Eliminate all activity associated with the requested vnode * and with all vnodes aliased to the requested vnode. */ int genfs_revoke(void *v) { struct vop_revoke_args /* { struct vnode *a_vp; int a_flags; } */ *ap = v; struct vnode *vp, *vq; struct proc *p = curproc; /* XXX */ #ifdef DIAGNOSTIC if ((ap->a_flags & REVOKEALL) == 0) panic("genfs_revoke: not revokeall"); #endif vp = ap->a_vp; simple_lock(&vp->v_interlock); if (vp->v_flag & VALIASED) { /* * If a vgone (or vclean) is already in progress, * wait until it is done and return. */ if (vp->v_flag & VXLOCK) { vp->v_flag |= VXWANT; ltsleep(vp, PINOD|PNORELOCK, "vop_revokeall", 0, &vp->v_interlock); return (0); } /* * Ensure that vp will not be vgone'd while we * are eliminating its aliases. */ vp->v_flag |= VXLOCK; simple_unlock(&vp->v_interlock); while (vp->v_flag & VALIASED) { simple_lock(&spechash_slock); for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { if (vq->v_rdev != vp->v_rdev || vq->v_type != vp->v_type || vp == vq) continue; simple_unlock(&spechash_slock); vgone(vq); break; } if (vq == NULLVP) simple_unlock(&spechash_slock); } /* * Remove the lock so that vgone below will * really eliminate the vnode after which time * vgone will awaken any sleepers. */ simple_lock(&vp->v_interlock); vp->v_flag &= ~VXLOCK; } vgonel(vp, p); return (0); } /* * Lock the node. */ int genfs_lock(void *v) { struct vop_lock_args /* { struct vnode *a_vp; int a_flags; } */ *ap = v; struct vnode *vp = ap->a_vp; return (lockmgr(vp->v_vnlock, ap->a_flags, &vp->v_interlock)); } /* * Unlock the node. */ int genfs_unlock(void *v) { struct vop_unlock_args /* { struct vnode *a_vp; int a_flags; } */ *ap = v; struct vnode *vp = ap->a_vp; return (lockmgr(vp->v_vnlock, ap->a_flags | LK_RELEASE, &vp->v_interlock)); } /* * Return whether or not the node is locked. */ int genfs_islocked(void *v) { struct vop_islocked_args /* { struct vnode *a_vp; } */ *ap = v; struct vnode *vp = ap->a_vp; return (lockstatus(vp->v_vnlock)); } /* * Stubs to use when there is no locking to be done on the underlying object. */ int genfs_nolock(void *v) { struct vop_lock_args /* { struct vnode *a_vp; int a_flags; struct proc *a_p; } */ *ap = v; /* * Since we are not using the lock manager, we must clear * the interlock here. */ if (ap->a_flags & LK_INTERLOCK) simple_unlock(&ap->a_vp->v_interlock); return (0); } int genfs_nounlock(void *v) { return (0); } int genfs_noislocked(void *v) { return (0); } /* * Local lease check for NFS servers. Just set up args and let * nqsrv_getlease() do the rest. If NFSSERVER is not in the kernel, * this is a null operation. */ int genfs_lease_check(void *v) { #ifdef NFSSERVER struct vop_lease_args /* { struct vnode *a_vp; struct proc *a_p; struct ucred *a_cred; int a_flag; } */ *ap = v; u_int32_t duration = 0; int cache; u_quad_t frev; (void) nqsrv_getlease(ap->a_vp, &duration, ND_CHECK | ap->a_flag, NQLOCALSLP, ap->a_p, (struct mbuf *)0, &cache, &frev, ap->a_cred); return (0); #else return (0); #endif /* NFSSERVER */ } int genfs_mmap(void *v) { return (0); } static __inline void genfs_rel_pages(struct vm_page **pgs, int npages) { int i; for (i = 0; i < npages; i++) { struct vm_page *pg = pgs[i]; if (pg == NULL) continue; if (pg->flags & PG_FAKE) { pg->flags |= PG_RELEASED; } } uvm_lock_pageq(); uvm_page_unbusy(pgs, npages); uvm_unlock_pageq(); } /* * generic VM getpages routine. * Return PG_BUSY pages for the given range, * reading from backing store if necessary. */ int genfs_getpages(void *v) { struct vop_getpages_args /* { struct vnode *a_vp; voff_t a_offset; struct vm_page **a_m; int *a_count; int a_centeridx; vm_prot_t a_access_type; int a_advice; int a_flags; } */ *ap = v; off_t newsize, diskeof, memeof; off_t offset, origoffset, startoffset, endoffset, raoffset; daddr_t lbn, blkno; int s, i, error, npages, orignpages, npgs, run, ridx, pidx, pcount; int fs_bshift, fs_bsize, dev_bshift; int flags = ap->a_flags; size_t bytes, iobytes, tailbytes, totalbytes, skipbytes; vaddr_t kva; struct buf *bp, *mbp; struct vnode *vp = ap->a_vp; struct vnode *devvp; struct genfs_node *gp = VTOG(vp); struct uvm_object *uobj = &vp->v_uobj; struct vm_page *pg, **pgs, *pgs_onstack[MAX_READ_AHEAD]; int pgs_size; struct ucred *cred = curproc->p_ucred; /* XXXUBC curlwp */ boolean_t async = (flags & PGO_SYNCIO) == 0; boolean_t write = (ap->a_access_type & VM_PROT_WRITE) != 0; boolean_t sawhole = FALSE; boolean_t overwrite = (flags & PGO_OVERWRITE) != 0; UVMHIST_FUNC("genfs_getpages"); UVMHIST_CALLED(ubchist); UVMHIST_LOG(ubchist, "vp %p off 0x%x/%x count %d", vp, ap->a_offset >> 32, ap->a_offset, *ap->a_count); /* XXXUBC temp limit */ if (*ap->a_count > MAX_READ_AHEAD) { panic("genfs_getpages: too many pages"); } error = 0; origoffset = ap->a_offset; orignpages = *ap->a_count; GOP_SIZE(vp, vp->v_size, &diskeof, GOP_SIZE_READ); if (flags & PGO_PASTEOF) { newsize = MAX(vp->v_size, origoffset + (orignpages << PAGE_SHIFT)); GOP_SIZE(vp, newsize, &memeof, GOP_SIZE_READ|GOP_SIZE_MEM); } else { GOP_SIZE(vp, vp->v_size, &memeof, GOP_SIZE_READ|GOP_SIZE_MEM); } KASSERT(ap->a_centeridx >= 0 || ap->a_centeridx <= orignpages); KASSERT((origoffset & (PAGE_SIZE - 1)) == 0 && origoffset >= 0); KASSERT(orignpages > 0); /* * Bounds-check the request. */ if (origoffset + (ap->a_centeridx << PAGE_SHIFT) >= memeof) { if ((flags & PGO_LOCKED) == 0) { simple_unlock(&uobj->vmobjlock); } UVMHIST_LOG(ubchist, "off 0x%x count %d goes past EOF 0x%x", origoffset, *ap->a_count, memeof,0); return (EINVAL); } /* * For PGO_LOCKED requests, just return whatever's in memory. */ if (flags & PGO_LOCKED) { uvn_findpages(uobj, origoffset, ap->a_count, ap->a_m, UFP_NOWAIT|UFP_NOALLOC| (write ? UFP_NORDONLY : 0)); return (ap->a_m[ap->a_centeridx] == NULL ? EBUSY : 0); } /* uobj is locked */ if (write && (vp->v_flag & VONWORKLST) == 0) { vn_syncer_add_to_worklist(vp, filedelay); } /* * find the requested pages and make some simple checks. * leave space in the page array for a whole block. */ if (vp->v_type == VREG) { fs_bshift = vp->v_mount->mnt_fs_bshift; dev_bshift = vp->v_mount->mnt_dev_bshift; } else { fs_bshift = DEV_BSHIFT; dev_bshift = DEV_BSHIFT; } fs_bsize = 1 << fs_bshift; orignpages = MIN(orignpages, round_page(memeof - origoffset) >> PAGE_SHIFT); npages = orignpages; startoffset = origoffset & ~(fs_bsize - 1); endoffset = round_page((origoffset + (npages << PAGE_SHIFT) + fs_bsize - 1) & ~(fs_bsize - 1)); endoffset = MIN(endoffset, round_page(memeof)); ridx = (origoffset - startoffset) >> PAGE_SHIFT; pgs_size = sizeof(struct vm_page *) * ((endoffset - startoffset) >> PAGE_SHIFT); if (pgs_size > sizeof(pgs_onstack)) { pgs = malloc(pgs_size, M_DEVBUF, M_NOWAIT | M_ZERO); if (pgs == NULL) { simple_unlock(&uobj->vmobjlock); return (ENOMEM); } } else { pgs = pgs_onstack; memset(pgs, 0, pgs_size); } UVMHIST_LOG(ubchist, "ridx %d npages %d startoff %ld endoff %ld", ridx, npages, startoffset, endoffset); if (uvn_findpages(uobj, origoffset, &npages, &pgs[ridx], async ? UFP_NOWAIT : UFP_ALL) != orignpages) { KASSERT(async != 0); genfs_rel_pages(&pgs[ridx], orignpages); simple_unlock(&uobj->vmobjlock); if (pgs != pgs_onstack) free(pgs, M_DEVBUF); return (EBUSY); } /* * if the pages are already resident, just return them. */ for (i = 0; i < npages; i++) { struct vm_page *pg = pgs[ridx + i]; if ((pg->flags & PG_FAKE) || (write && (pg->flags & PG_RDONLY))) { break; } } if (i == npages) { UVMHIST_LOG(ubchist, "returning cached pages", 0,0,0,0); raoffset = origoffset + (orignpages << PAGE_SHIFT); npages += ridx; goto raout; } /* * if PGO_OVERWRITE is set, don't bother reading the pages. */ if (flags & PGO_OVERWRITE) { UVMHIST_LOG(ubchist, "PGO_OVERWRITE",0,0,0,0); for (i = 0; i < npages; i++) { struct vm_page *pg = pgs[ridx + i]; pg->flags &= ~(PG_RDONLY|PG_CLEAN); } npages += ridx; goto out; } /* * the page wasn't resident and we're not overwriting, * so we're going to have to do some i/o. * find any additional pages needed to cover the expanded range. */ npages = (endoffset - startoffset) >> PAGE_SHIFT; if (startoffset != origoffset || npages != orignpages) { /* * we need to avoid deadlocks caused by locking * additional pages at lower offsets than pages we * already have locked. unlock them all and start over. */ genfs_rel_pages(&pgs[ridx], orignpages); memset(pgs, 0, pgs_size); UVMHIST_LOG(ubchist, "reset npages start 0x%x end 0x%x", startoffset, endoffset, 0,0); npgs = npages; if (uvn_findpages(uobj, startoffset, &npgs, pgs, async ? UFP_NOWAIT : UFP_ALL) != npages) { KASSERT(async != 0); genfs_rel_pages(pgs, npages); simple_unlock(&uobj->vmobjlock); if (pgs != pgs_onstack) free(pgs, M_DEVBUF); return (EBUSY); } } simple_unlock(&uobj->vmobjlock); /* * read the desired page(s). */ totalbytes = npages << PAGE_SHIFT; bytes = MIN(totalbytes, MAX(diskeof - startoffset, 0)); tailbytes = totalbytes - bytes; skipbytes = 0; kva = uvm_pagermapin(pgs, npages, UVMPAGER_MAPIN_READ | UVMPAGER_MAPIN_WAITOK); s = splbio(); mbp = pool_get(&bufpool, PR_WAITOK); splx(s); BUF_INIT(mbp); mbp->b_bufsize = totalbytes; mbp->b_data = (void *)kva; mbp->b_resid = mbp->b_bcount = bytes; mbp->b_flags = B_BUSY|B_READ| (async ? B_CALL|B_ASYNC : 0); mbp->b_iodone = (async ? uvm_aio_biodone : 0); mbp->b_vp = vp; /* * if EOF is in the middle of the range, zero the part past EOF. * if the page including EOF is not PG_FAKE, skip over it since * in that case it has valid data that we need to preserve. */ if (tailbytes > 0) { size_t tailstart = bytes; if ((pgs[bytes >> PAGE_SHIFT]->flags & PG_FAKE) == 0) { tailstart = round_page(tailstart); tailbytes -= tailstart - bytes; } UVMHIST_LOG(ubchist, "tailbytes %p 0x%x 0x%x", kva, tailstart, tailbytes,0); memset((void *)(kva + tailstart), 0, tailbytes); } /* * now loop over the pages, reading as needed. */ if (write) { lockmgr(&gp->g_glock, LK_EXCLUSIVE, NULL); } else { lockmgr(&gp->g_glock, LK_SHARED, NULL); } bp = NULL; for (offset = startoffset; bytes > 0; offset += iobytes, bytes -= iobytes) { /* * skip pages which don't need to be read. */ pidx = (offset - startoffset) >> PAGE_SHIFT; while ((pgs[pidx]->flags & (PG_FAKE|PG_RDONLY)) == 0) { size_t b; KASSERT((offset & (PAGE_SIZE - 1)) == 0); b = MIN(PAGE_SIZE, bytes); offset += b; bytes -= b; skipbytes += b; pidx++; UVMHIST_LOG(ubchist, "skipping, new offset 0x%x", offset, 0,0,0); if (bytes == 0) { goto loopdone; } } /* * bmap the file to find out the blkno to read from and * how much we can read in one i/o. if bmap returns an error, * skip the rest of the top-level i/o. */ lbn = offset >> fs_bshift; error = VOP_BMAP(vp, lbn, &devvp, &blkno, &run); if (error) { UVMHIST_LOG(ubchist, "VOP_BMAP lbn 0x%x -> %d\n", lbn, error,0,0); skipbytes += bytes; goto loopdone; } /* * see how many pages can be read with this i/o. * reduce the i/o size if necessary to avoid * overwriting pages with valid data. */ iobytes = MIN((((off_t)lbn + 1 + run) << fs_bshift) - offset, bytes); if (offset + iobytes > round_page(offset)) { pcount = 1; while (pidx + pcount < npages && pgs[pidx + pcount]->flags & PG_FAKE) { pcount++; } iobytes = MIN(iobytes, (pcount << PAGE_SHIFT) - (offset - trunc_page(offset))); } /* * if this block isn't allocated, zero it instead of * reading it. if this is a read access, mark the * pages we zeroed PG_RDONLY. */ if (blkno < 0) { int holepages = (round_page(offset + iobytes) - trunc_page(offset)) >> PAGE_SHIFT; UVMHIST_LOG(ubchist, "lbn 0x%x -> HOLE", lbn,0,0,0); sawhole = TRUE; memset((char *)kva + (offset - startoffset), 0, iobytes); skipbytes += iobytes; for (i = 0; i < holepages; i++) { if (write) { pgs[pidx + i]->flags &= ~PG_CLEAN; } else { pgs[pidx + i]->flags |= PG_RDONLY; } } continue; } /* * allocate a sub-buf for this piece of the i/o * (or just use mbp if there's only 1 piece), * and start it going. */ if (offset == startoffset && iobytes == bytes) { bp = mbp; } else { s = splbio(); bp = pool_get(&bufpool, PR_WAITOK); splx(s); BUF_INIT(bp); bp->b_data = (char *)kva + offset - startoffset; bp->b_resid = bp->b_bcount = iobytes; bp->b_flags = B_BUSY|B_READ|B_CALL|B_ASYNC; bp->b_iodone = uvm_aio_biodone1; bp->b_vp = vp; bp->b_proc = NULL; } bp->b_lblkno = 0; bp->b_private = mbp; if (devvp->v_type == VBLK) { bp->b_dev = devvp->v_rdev; } /* adjust physical blkno for partial blocks */ bp->b_blkno = blkno + ((offset - ((off_t)lbn << fs_bshift)) >> dev_bshift); UVMHIST_LOG(ubchist, "bp %p offset 0x%x bcount 0x%x blkno 0x%x", bp, offset, iobytes, bp->b_blkno); if (async) BIO_SETPRIO(bp, BPRIO_TIMELIMITED); else BIO_SETPRIO(bp, BPRIO_TIMECRITICAL); VOP_STRATEGY(bp->b_vp, bp); } loopdone: if (skipbytes) { s = splbio(); if (error) { mbp->b_flags |= B_ERROR; mbp->b_error = error; } mbp->b_resid -= skipbytes; if (mbp->b_resid == 0) { biodone(mbp); } splx(s); } if (async) { UVMHIST_LOG(ubchist, "returning 0 (async)",0,0,0,0); lockmgr(&gp->g_glock, LK_RELEASE, NULL); if (pgs != pgs_onstack) free(pgs, M_DEVBUF); return (0); } if (bp != NULL) { error = biowait(mbp); } s = splbio(); pool_put(&bufpool, mbp); splx(s); uvm_pagermapout(kva, npages); raoffset = startoffset + totalbytes; /* * if this we encountered a hole then we have to do a little more work. * for read faults, we marked the page PG_RDONLY so that future * write accesses to the page will fault again. * for write faults, we must make sure that the backing store for * the page is completely allocated while the pages are locked. */ if (!error && sawhole && write) { for (i = 0; i < npages; i++) { if (pgs[i] == NULL) { continue; } pgs[i]->flags &= ~PG_CLEAN; UVMHIST_LOG(ubchist, "mark dirty pg %p", pgs[i],0,0,0); } error = GOP_ALLOC(vp, startoffset, npages << PAGE_SHIFT, 0, cred); UVMHIST_LOG(ubchist, "gop_alloc off 0x%x/0x%x -> %d", startoffset, npages << PAGE_SHIFT, error,0); } lockmgr(&gp->g_glock, LK_RELEASE, NULL); simple_lock(&uobj->vmobjlock); /* * see if we want to start any readahead. * XXXUBC for now, just read the next 128k on 64k boundaries. * this is pretty nonsensical, but it is 50% faster than reading * just the next 64k. */ raout: if (!error && !async && !write && ((int)raoffset & 0xffff) == 0 && PAGE_SHIFT <= 16) { off_t rasize; int rapages, err, i, skipped; /* XXXUBC temp limit, from above */ rapages = MIN(MIN(1 << (16 - PAGE_SHIFT), MAX_READ_AHEAD), genfs_rapages); rasize = rapages << PAGE_SHIFT; for (i = skipped = 0; i < genfs_racount; i++) { err = VOP_GETPAGES(vp, raoffset, NULL, &rapages, 0, VM_PROT_READ, 0, 0); simple_lock(&uobj->vmobjlock); if (err) { if (err != EBUSY || skipped++ == genfs_raskip) break; } raoffset += rasize; rapages = rasize >> PAGE_SHIFT; } } /* * we're almost done! release the pages... * for errors, we free the pages. * otherwise we activate them and mark them as valid and clean. * also, unbusy pages that were not actually requested. */ if (error) { for (i = 0; i < npages; i++) { if (pgs[i] == NULL) { continue; } UVMHIST_LOG(ubchist, "examining pg %p flags 0x%x", pgs[i], pgs[i]->flags, 0,0); if (pgs[i]->flags & PG_FAKE) { pgs[i]->flags |= PG_RELEASED; } } uvm_lock_pageq(); uvm_page_unbusy(pgs, npages); uvm_unlock_pageq(); simple_unlock(&uobj->vmobjlock); UVMHIST_LOG(ubchist, "returning error %d", error,0,0,0); if (pgs != pgs_onstack) free(pgs, M_DEVBUF); return (error); } out: UVMHIST_LOG(ubchist, "succeeding, npages %d", npages,0,0,0); uvm_lock_pageq(); for (i = 0; i < npages; i++) { pg = pgs[i]; if (pg == NULL) { continue; } UVMHIST_LOG(ubchist, "examining pg %p flags 0x%x", pg, pg->flags, 0,0); if (pg->flags & PG_FAKE && !overwrite) { pg->flags &= ~(PG_FAKE); pmap_clear_modify(pgs[i]); } if (write) { pg->flags &= ~(PG_RDONLY); } if (i < ridx || i >= ridx + orignpages || async) { UVMHIST_LOG(ubchist, "unbusy pg %p offset 0x%x", pg, pg->offset,0,0); if (pg->flags & PG_WANTED) { wakeup(pg); } if (pg->flags & PG_FAKE) { KASSERT(overwrite); uvm_pagezero(pg); } if (pg->flags & PG_RELEASED) { uvm_pagefree(pg); continue; } uvm_pageactivate(pg); pg->flags &= ~(PG_WANTED|PG_BUSY|PG_FAKE); UVM_PAGE_OWN(pg, NULL); } } uvm_unlock_pageq(); simple_unlock(&uobj->vmobjlock); if (ap->a_m != NULL) { memcpy(ap->a_m, &pgs[ridx], orignpages * sizeof(struct vm_page *)); } if (pgs != pgs_onstack) free(pgs, M_DEVBUF); return (0); } /* * generic VM putpages routine. * Write the given range of pages to backing store. * * => "offhi == 0" means flush all pages at or after "offlo". * => object should be locked by caller. we may _unlock_ the object * if (and only if) we need to clean a page (PGO_CLEANIT), or * if PGO_SYNCIO is set and there are pages busy. * we return with the object locked. * => if PGO_CLEANIT or PGO_SYNCIO is set, we may block (due to I/O). * thus, a caller might want to unlock higher level resources * (e.g. vm_map) before calling flush. * => if neither PGO_CLEANIT nor PGO_SYNCIO is set, then we will neither * unlock the object nor block. * => if PGO_ALLPAGES is set, then all pages in the object will be processed. * => NOTE: we rely on the fact that the object's memq is a TAILQ and * that new pages are inserted on the tail end of the list. thus, * we can make a complete pass through the object in one go by starting * at the head and working towards the tail (new pages are put in * front of us). * => NOTE: we are allowed to lock the page queues, so the caller * must not be holding the page queue lock. * * note on "cleaning" object and PG_BUSY pages: * this routine is holding the lock on the object. the only time * that it can run into a PG_BUSY page that it does not own is if * some other process has started I/O on the page (e.g. either * a pagein, or a pageout). if the PG_BUSY page is being paged * in, then it can not be dirty (!PG_CLEAN) because no one has * had a chance to modify it yet. if the PG_BUSY page is being * paged out then it means that someone else has already started * cleaning the page for us (how nice!). in this case, if we * have syncio specified, then after we make our pass through the * object we need to wait for the other PG_BUSY pages to clear * off (i.e. we need to do an iosync). also note that once a * page is PG_BUSY it must stay in its object until it is un-busyed. * * note on page traversal: * we can traverse the pages in an object either by going down the * linked list in "uobj->memq", or we can go over the address range * by page doing hash table lookups for each address. depending * on how many pages are in the object it may be cheaper to do one * or the other. we set "by_list" to true if we are using memq. * if the cost of a hash lookup was equal to the cost of the list * traversal we could compare the number of pages in the start->stop * range to the total number of pages in the object. however, it * seems that a hash table lookup is more expensive than the linked * list traversal, so we multiply the number of pages in the * range by an estimate of the relatively higher cost of the hash lookup. */ int genfs_putpages(void *v) { struct vop_putpages_args /* { struct vnode *a_vp; voff_t a_offlo; voff_t a_offhi; int a_flags; } */ *ap = v; struct vnode *vp = ap->a_vp; struct uvm_object *uobj = &vp->v_uobj; struct simplelock *slock = &uobj->vmobjlock; off_t startoff = ap->a_offlo; off_t endoff = ap->a_offhi; off_t off; int flags = ap->a_flags; /* Even for strange MAXPHYS, the shift rounds down to a page */ const int maxpages = MAXPHYS >> PAGE_SHIFT; int i, s, error, npages, nback; int freeflag; struct vm_page *pgs[maxpages], *pg, *nextpg, *tpg, curmp, endmp; boolean_t wasclean, by_list, needs_clean, yield; boolean_t async = (flags & PGO_SYNCIO) == 0; boolean_t pagedaemon = curproc == uvm.pagedaemon_proc; struct lwp *l = curlwp ? curlwp : &lwp0; UVMHIST_FUNC("genfs_putpages"); UVMHIST_CALLED(ubchist); KASSERT(flags & (PGO_CLEANIT|PGO_FREE|PGO_DEACTIVATE)); KASSERT((startoff & PAGE_MASK) == 0 && (endoff & PAGE_MASK) == 0); KASSERT(startoff < endoff || endoff == 0); UVMHIST_LOG(ubchist, "vp %p pages %d off 0x%x len 0x%x", vp, uobj->uo_npages, startoff, endoff - startoff); if (uobj->uo_npages == 0) { s = splbio(); if (LIST_FIRST(&vp->v_dirtyblkhd) == NULL && (vp->v_flag & VONWORKLST)) { vp->v_flag &= ~VONWORKLST; LIST_REMOVE(vp, v_synclist); } splx(s); simple_unlock(slock); return (0); } /* * the vnode has pages, set up to process the request. */ error = 0; s = splbio(); simple_lock(&global_v_numoutput_slock); wasclean = (vp->v_numoutput == 0); simple_unlock(&global_v_numoutput_slock); splx(s); off = startoff; if (endoff == 0 || flags & PGO_ALLPAGES) { endoff = trunc_page(LLONG_MAX); } by_list = (uobj->uo_npages <= ((endoff - startoff) >> PAGE_SHIFT) * UVM_PAGE_HASH_PENALTY); /* * start the loop. when scanning by list, hold the last page * in the list before we start. pages allocated after we start * will be added to the end of the list, so we can stop at the * current last page. */ freeflag = pagedaemon ? PG_PAGEOUT : PG_RELEASED; curmp.uobject = uobj; curmp.offset = (voff_t)-1; curmp.flags = PG_BUSY; endmp.uobject = uobj; endmp.offset = (voff_t)-1; endmp.flags = PG_BUSY; if (by_list) { pg = TAILQ_FIRST(&uobj->memq); TAILQ_INSERT_TAIL(&uobj->memq, &endmp, listq); PHOLD(l); } else { pg = uvm_pagelookup(uobj, off); } nextpg = NULL; while (by_list || off < endoff) { /* * if the current page is not interesting, move on to the next. */ KASSERT(pg == NULL || pg->uobject == uobj); KASSERT(pg == NULL || (pg->flags & (PG_RELEASED|PG_PAGEOUT)) == 0 || (pg->flags & PG_BUSY) != 0); if (by_list) { if (pg == &endmp) { break; } if (pg->offset < startoff || pg->offset >= endoff || pg->flags & (PG_RELEASED|PG_PAGEOUT)) { pg = TAILQ_NEXT(pg, listq); continue; } off = pg->offset; } else if (pg == NULL || pg->flags & (PG_RELEASED|PG_PAGEOUT)) { off += PAGE_SIZE; if (off < endoff) { pg = uvm_pagelookup(uobj, off); } continue; } /* * if the current page needs to be cleaned and it's busy, * wait for it to become unbusy. */ yield = (l->l_cpu->ci_schedstate.spc_flags & SPCF_SHOULDYIELD) && !pagedaemon; if (pg->flags & PG_BUSY || yield) { UVMHIST_LOG(ubchist, "busy %p", pg,0,0,0); if (flags & PGO_BUSYFAIL && pg->flags & PG_BUSY) { UVMHIST_LOG(ubchist, "busyfail %p", pg, 0,0,0); error = EDEADLK; break; } KASSERT(!pagedaemon); if (by_list) { TAILQ_INSERT_BEFORE(pg, &curmp, listq); UVMHIST_LOG(ubchist, "curmp next %p", TAILQ_NEXT(&curmp, listq), 0,0,0); } if (yield) { simple_unlock(slock); preempt(1); simple_lock(slock); } else { pg->flags |= PG_WANTED; UVM_UNLOCK_AND_WAIT(pg, slock, 0, "genput", 0); simple_lock(slock); } if (by_list) { UVMHIST_LOG(ubchist, "after next %p", TAILQ_NEXT(&curmp, listq), 0,0,0); pg = TAILQ_NEXT(&curmp, listq); TAILQ_REMOVE(&uobj->memq, &curmp, listq); } else { pg = uvm_pagelookup(uobj, off); } continue; } /* * if we're freeing, remove all mappings of the page now. * if we're cleaning, check if the page is needs to be cleaned. */ if (flags & PGO_FREE) { pmap_page_protect(pg, VM_PROT_NONE); } if (flags & PGO_CLEANIT) { needs_clean = pmap_clear_modify(pg) || (pg->flags & PG_CLEAN) == 0; pg->flags |= PG_CLEAN; } else { needs_clean = FALSE; } /* * if we're cleaning, build a cluster. * the cluster will consist of pages which are currently dirty, * but they will be returned to us marked clean. * if not cleaning, just operate on the one page. */ if (needs_clean) { wasclean = FALSE; memset(pgs, 0, sizeof(pgs)); pg->flags |= PG_BUSY; UVM_PAGE_OWN(pg, "genfs_putpages"); /* * first look backward. */ npages = MIN(maxpages >> 1, off >> PAGE_SHIFT); nback = npages; uvn_findpages(uobj, off - PAGE_SIZE, &nback, &pgs[0], UFP_NOWAIT|UFP_NOALLOC|UFP_DIRTYONLY|UFP_BACKWARD); if (nback) { memmove(&pgs[0], &pgs[npages - nback], nback * sizeof(pgs[0])); if (npages - nback < nback) memset(&pgs[nback], 0, (npages - nback) * sizeof(pgs[0])); else memset(&pgs[npages - nback], 0, nback * sizeof(pgs[0])); } /* * then plug in our page of interest. */ pgs[nback] = pg; /* * then look forward to fill in the remaining space in * the array of pages. */ npages = maxpages - nback - 1; uvn_findpages(uobj, off + PAGE_SIZE, &npages, &pgs[nback + 1], UFP_NOWAIT|UFP_NOALLOC|UFP_DIRTYONLY); npages += nback + 1; } else { pgs[0] = pg; npages = 1; nback = 0; } /* * apply FREE or DEACTIVATE options if requested. */ if (flags & (PGO_DEACTIVATE|PGO_FREE)) { uvm_lock_pageq(); } for (i = 0; i < npages; i++) { tpg = pgs[i]; KASSERT(tpg->uobject == uobj); if (by_list && tpg == TAILQ_NEXT(pg, listq)) pg = tpg; if (tpg->offset < startoff || tpg->offset >= endoff) continue; if (flags & PGO_DEACTIVATE && (tpg->pqflags & PQ_INACTIVE) == 0 && tpg->wire_count == 0) { (void) pmap_clear_reference(tpg); uvm_pagedeactivate(tpg); } else if (flags & PGO_FREE) { pmap_page_protect(tpg, VM_PROT_NONE); if (tpg->flags & PG_BUSY) { tpg->flags |= freeflag; if (pagedaemon) { uvmexp.paging++; uvm_pagedequeue(tpg); } } else { /* * ``page is not busy'' * implies that npages is 1 * and needs_clean is false. */ nextpg = TAILQ_NEXT(tpg, listq); uvm_pagefree(tpg); if (pagedaemon) uvmexp.pdfreed++; } } } if (flags & (PGO_DEACTIVATE|PGO_FREE)) { uvm_unlock_pageq(); } if (needs_clean) { /* * start the i/o. if we're traversing by list, * keep our place in the list with a marker page. */ if (by_list) { TAILQ_INSERT_AFTER(&uobj->memq, pg, &curmp, listq); } simple_unlock(slock); error = GOP_WRITE(vp, pgs, npages, flags); simple_lock(slock); if (by_list) { pg = TAILQ_NEXT(&curmp, listq); TAILQ_REMOVE(&uobj->memq, &curmp, listq); } if (error) { break; } if (by_list) { continue; } } /* * find the next page and continue if there was no error. */ if (by_list) { if (nextpg) { pg = nextpg; nextpg = NULL; } else { pg = TAILQ_NEXT(pg, listq); } } else { off += (npages - nback) << PAGE_SHIFT; if (off < endoff) { pg = uvm_pagelookup(uobj, off); } } } if (by_list) { TAILQ_REMOVE(&uobj->memq, &endmp, listq); PRELE(l); } /* * if we're cleaning and there was nothing to clean, * take us off the syncer list. if we started any i/o * and we're doing sync i/o, wait for all writes to finish. */ s = splbio(); if ((flags & PGO_CLEANIT) && wasclean && startoff == 0 && endoff == trunc_page(LLONG_MAX) && LIST_FIRST(&vp->v_dirtyblkhd) == NULL && (vp->v_flag & VONWORKLST)) { vp->v_flag &= ~VONWORKLST; LIST_REMOVE(vp, v_synclist); } splx(s); if (!wasclean && !async) { s = splbio(); /* * XXX - we want simple_unlock(&global_v_numoutput_slock); * but the slot in ltsleep() is taken! * XXX - try to recover from missed wakeups with a timeout.. * must think of something better. */ while (vp->v_numoutput != 0) { vp->v_flag |= VBWAIT; UVM_UNLOCK_AND_WAIT(&vp->v_numoutput, slock, FALSE, "genput2", hz); simple_lock(slock); } splx(s); } simple_unlock(&uobj->vmobjlock); return (error); } int genfs_gop_write(struct vnode *vp, struct vm_page **pgs, int npages, int flags) { int s, error, run; int fs_bshift, dev_bshift; vaddr_t kva; off_t eof, offset, startoffset; size_t bytes, iobytes, skipbytes; daddr_t lbn, blkno; struct vm_page *pg; struct buf *mbp, *bp; struct vnode *devvp; boolean_t async = (flags & PGO_SYNCIO) == 0; UVMHIST_FUNC("genfs_gop_write"); UVMHIST_CALLED(ubchist); UVMHIST_LOG(ubchist, "vp %p pgs %p npages %d flags 0x%x", vp, pgs, npages, flags); GOP_SIZE(vp, vp->v_size, &eof, GOP_SIZE_WRITE); if (vp->v_type == VREG) { fs_bshift = vp->v_mount->mnt_fs_bshift; dev_bshift = vp->v_mount->mnt_dev_bshift; } else { fs_bshift = DEV_BSHIFT; dev_bshift = DEV_BSHIFT; } error = 0; pg = pgs[0]; startoffset = pg->offset; bytes = MIN(npages << PAGE_SHIFT, eof - startoffset); skipbytes = 0; KASSERT(bytes != 0); kva = uvm_pagermapin(pgs, npages, UVMPAGER_MAPIN_WRITE | UVMPAGER_MAPIN_WAITOK); s = splbio(); simple_lock(&global_v_numoutput_slock); vp->v_numoutput += 2; simple_unlock(&global_v_numoutput_slock); mbp = pool_get(&bufpool, PR_WAITOK); BUF_INIT(mbp); UVMHIST_LOG(ubchist, "vp %p mbp %p num now %d bytes 0x%x", vp, mbp, vp->v_numoutput, bytes); splx(s); mbp->b_bufsize = npages << PAGE_SHIFT; mbp->b_data = (void *)kva; mbp->b_resid = mbp->b_bcount = bytes; mbp->b_flags = B_BUSY|B_WRITE|B_AGE| (async ? (B_CALL|B_ASYNC) : 0); mbp->b_iodone = uvm_aio_biodone; mbp->b_vp = vp; bp = NULL; for (offset = startoffset; bytes > 0; offset += iobytes, bytes -= iobytes) { lbn = offset >> fs_bshift; error = VOP_BMAP(vp, lbn, &devvp, &blkno, &run); if (error) { UVMHIST_LOG(ubchist, "VOP_BMAP() -> %d", error,0,0,0); skipbytes += bytes; bytes = 0; break; } iobytes = MIN((((off_t)lbn + 1 + run) << fs_bshift) - offset, bytes); if (blkno == (daddr_t)-1) { skipbytes += iobytes; continue; } /* if it's really one i/o, don't make a second buf */ if (offset == startoffset && iobytes == bytes) { bp = mbp; } else { s = splbio(); V_INCR_NUMOUTPUT(vp); bp = pool_get(&bufpool, PR_WAITOK); UVMHIST_LOG(ubchist, "vp %p bp %p num now %d", vp, bp, vp->v_numoutput, 0); splx(s); BUF_INIT(bp); bp->b_data = (char *)kva + (vaddr_t)(offset - pg->offset); bp->b_resid = bp->b_bcount = iobytes; bp->b_flags = B_BUSY|B_WRITE|B_CALL|B_ASYNC; bp->b_iodone = uvm_aio_biodone1; bp->b_vp = vp; } bp->b_lblkno = 0; bp->b_private = mbp; if (devvp->v_type == VBLK) { bp->b_dev = devvp->v_rdev; } /* adjust physical blkno for partial blocks */ bp->b_blkno = blkno + ((offset - ((off_t)lbn << fs_bshift)) >> dev_bshift); UVMHIST_LOG(ubchist, "vp %p offset 0x%x bcount 0x%x blkno 0x%x", vp, offset, bp->b_bcount, bp->b_blkno); if (curproc == uvm.pagedaemon_proc) BIO_SETPRIO(bp, BPRIO_TIMELIMITED); else if (async) BIO_SETPRIO(bp, BPRIO_TIMENONCRITICAL); else BIO_SETPRIO(bp, BPRIO_TIMECRITICAL); VOP_STRATEGY(bp->b_vp, bp); } if (skipbytes) { UVMHIST_LOG(ubchist, "skipbytes %d", skipbytes, 0,0,0); s = splbio(); if (error) { mbp->b_flags |= B_ERROR; mbp->b_error = error; } mbp->b_resid -= skipbytes; if (mbp->b_resid == 0) { biodone(mbp); } splx(s); } if (async) { UVMHIST_LOG(ubchist, "returning 0 (async)", 0,0,0,0); return (0); } UVMHIST_LOG(ubchist, "waiting for mbp %p", mbp,0,0,0); error = biowait(mbp); uvm_aio_aiodone(mbp); UVMHIST_LOG(ubchist, "returning, error %d", error,0,0,0); return (error); } /* * VOP_PUTPAGES() for vnodes which never have pages. */ int genfs_null_putpages(void *v) { struct vop_putpages_args /* { struct vnode *a_vp; voff_t a_offlo; voff_t a_offhi; int a_flags; } */ *ap = v; struct vnode *vp = ap->a_vp; KASSERT(vp->v_uobj.uo_npages == 0); simple_unlock(&vp->v_interlock); return (0); } void genfs_node_init(struct vnode *vp, struct genfs_ops *ops) { struct genfs_node *gp = VTOG(vp); lockinit(&gp->g_glock, PINOD, "glock", 0, 0); gp->g_op = ops; } void genfs_size(struct vnode *vp, off_t size, off_t *eobp, int flags) { int bsize; bsize = 1 << vp->v_mount->mnt_fs_bshift; *eobp = (size + bsize - 1) & ~(bsize - 1); } int genfs_compat_getpages(void *v) { struct vop_getpages_args /* { struct vnode *a_vp; voff_t a_offset; struct vm_page **a_m; int *a_count; int a_centeridx; vm_prot_t a_access_type; int a_advice; int a_flags; } */ *ap = v; off_t origoffset; struct vnode *vp = ap->a_vp; struct uvm_object *uobj = &vp->v_uobj; struct vm_page *pg, **pgs; vaddr_t kva; int i, error, orignpages, npages; struct iovec iov; struct uio uio; struct ucred *cred = curproc->p_ucred; boolean_t write = (ap->a_access_type & VM_PROT_WRITE) != 0; error = 0; origoffset = ap->a_offset; orignpages = *ap->a_count; pgs = ap->a_m; if (write && (vp->v_flag & VONWORKLST) == 0) { vn_syncer_add_to_worklist(vp, filedelay); } if (ap->a_flags & PGO_LOCKED) { uvn_findpages(uobj, origoffset, ap->a_count, ap->a_m, UFP_NOWAIT|UFP_NOALLOC| (write ? UFP_NORDONLY : 0)); return (ap->a_m[ap->a_centeridx] == NULL ? EBUSY : 0); } if (origoffset + (ap->a_centeridx << PAGE_SHIFT) >= vp->v_size) { simple_unlock(&uobj->vmobjlock); return (EINVAL); } npages = orignpages; uvn_findpages(uobj, origoffset, &npages, pgs, UFP_ALL); simple_unlock(&uobj->vmobjlock); kva = uvm_pagermapin(pgs, npages, UVMPAGER_MAPIN_READ | UVMPAGER_MAPIN_WAITOK); for (i = 0; i < npages; i++) { pg = pgs[i]; if ((pg->flags & PG_FAKE) == 0) { continue; } iov.iov_base = (char *)kva + (i << PAGE_SHIFT); iov.iov_len = PAGE_SIZE; uio.uio_iov = &iov; uio.uio_iovcnt = 1; uio.uio_offset = origoffset + (i << PAGE_SHIFT); uio.uio_segflg = UIO_SYSSPACE; uio.uio_rw = UIO_READ; uio.uio_resid = PAGE_SIZE; uio.uio_procp = NULL; /* XXX vn_lock */ error = VOP_READ(vp, &uio, 0, cred); if (error) { break; } if (uio.uio_resid) { memset(iov.iov_base, 0, uio.uio_resid); } } uvm_pagermapout(kva, npages); simple_lock(&uobj->vmobjlock); uvm_lock_pageq(); for (i = 0; i < npages; i++) { pg = pgs[i]; if (error && (pg->flags & PG_FAKE) != 0) { pg->flags |= PG_RELEASED; } else { pmap_clear_modify(pg); uvm_pageactivate(pg); } } if (error) { uvm_page_unbusy(pgs, npages); } uvm_unlock_pageq(); simple_unlock(&uobj->vmobjlock); return (error); } int genfs_compat_gop_write(struct vnode *vp, struct vm_page **pgs, int npages, int flags) { off_t offset; struct iovec iov; struct uio uio; struct ucred *cred = curproc->p_ucred; struct buf *bp; vaddr_t kva; int s, error; offset = pgs[0]->offset; kva = uvm_pagermapin(pgs, npages, UVMPAGER_MAPIN_WRITE | UVMPAGER_MAPIN_WAITOK); iov.iov_base = (void *)kva; iov.iov_len = npages << PAGE_SHIFT; uio.uio_iov = &iov; uio.uio_iovcnt = 1; uio.uio_offset = offset; uio.uio_segflg = UIO_SYSSPACE; uio.uio_rw = UIO_WRITE; uio.uio_resid = npages << PAGE_SHIFT; uio.uio_procp = NULL; /* XXX vn_lock */ error = VOP_WRITE(vp, &uio, 0, cred); s = splbio(); V_INCR_NUMOUTPUT(vp); bp = pool_get(&bufpool, PR_WAITOK); splx(s); BUF_INIT(bp); bp->b_flags = B_BUSY | B_WRITE | B_AGE; bp->b_vp = vp; bp->b_lblkno = offset >> vp->v_mount->mnt_fs_bshift; bp->b_data = (char *)kva; bp->b_bcount = npages << PAGE_SHIFT; bp->b_bufsize = npages << PAGE_SHIFT; bp->b_resid = 0; if (error) { bp->b_flags |= B_ERROR; bp->b_error = error; } uvm_aio_aiodone(bp); return (error); } static void filt_genfsdetach(struct knote *kn) { struct vnode *vp = (struct vnode *)kn->kn_hook; /* XXXLUKEM lock the struct? */ SLIST_REMOVE(&vp->v_klist, kn, knote, kn_selnext); } static int filt_genfsread(struct knote *kn, long hint) { struct vnode *vp = (struct vnode *)kn->kn_hook; /* * filesystem is gone, so set the EOF flag and schedule * the knote for deletion. */ if (hint == NOTE_REVOKE) { kn->kn_flags |= (EV_EOF | EV_ONESHOT); return (1); } /* XXXLUKEM lock the struct? */ kn->kn_data = vp->v_size - kn->kn_fp->f_offset; return (kn->kn_data != 0); } static int filt_genfsvnode(struct knote *kn, long hint) { if (kn->kn_sfflags & hint) kn->kn_fflags |= hint; if (hint == NOTE_REVOKE) { kn->kn_flags |= EV_EOF; return (1); } return (kn->kn_fflags != 0); } static const struct filterops genfsread_filtops = { 1, NULL, filt_genfsdetach, filt_genfsread }; static const struct filterops genfsvnode_filtops = { 1, NULL, filt_genfsdetach, filt_genfsvnode }; int genfs_kqfilter(void *v) { struct vop_kqfilter_args /* { struct vnode *a_vp; struct knote *a_kn; } */ *ap = v; struct vnode *vp; struct knote *kn; vp = ap->a_vp; kn = ap->a_kn; switch (kn->kn_filter) { case EVFILT_READ: kn->kn_fop = &genfsread_filtops; break; case EVFILT_VNODE: kn->kn_fop = &genfsvnode_filtops; break; default: return (1); } kn->kn_hook = vp; /* XXXLUKEM lock the struct? */ SLIST_INSERT_HEAD(&vp->v_klist, kn, kn_selnext); return (0); }