1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2004 Poul-Henning Kamp 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/bio.h> 35 #include <sys/kernel.h> 36 #include <sys/lock.h> 37 #include <sys/malloc.h> 38 #include <sys/mutex.h> 39 #include <sys/sbuf.h> 40 #include <sys/vnode.h> 41 #include <sys/mount.h> 42 43 #include <geom/geom.h> 44 #include <geom/geom_vfs.h> 45 46 /* 47 * subroutines for use by filesystems. 48 * 49 * XXX: should maybe live somewhere else ? 50 */ 51 #include <sys/buf.h> 52 53 struct g_vfs_softc { 54 struct mtx sc_mtx; 55 struct bufobj *sc_bo; 56 struct g_event *sc_event; 57 int sc_active; 58 bool sc_orphaned; 59 int sc_enxio_active; 60 int sc_enxio_reported; 61 }; 62 63 static struct buf_ops __g_vfs_bufops = { 64 .bop_name = "GEOM_VFS", 65 .bop_write = bufwrite, 66 .bop_strategy = g_vfs_strategy, 67 .bop_sync = bufsync, 68 .bop_bdflush = bufbdflush 69 }; 70 71 struct buf_ops *g_vfs_bufops = &__g_vfs_bufops; 72 73 static g_orphan_t g_vfs_orphan; 74 75 static struct g_class g_vfs_class = { 76 .name = "VFS", 77 .version = G_VERSION, 78 .orphan = g_vfs_orphan, 79 }; 80 81 DECLARE_GEOM_CLASS(g_vfs_class, g_vfs); 82 83 static void 84 g_vfs_destroy(void *arg, int flags __unused) 85 { 86 struct g_consumer *cp; 87 88 g_topology_assert(); 89 cp = arg; 90 if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0) 91 g_access(cp, -cp->acr, -cp->acw, -cp->ace); 92 g_detach(cp); 93 if (cp->geom->softc == NULL) 94 g_wither_geom(cp->geom, ENXIO); 95 } 96 97 static void 98 g_vfs_done(struct bio *bip) 99 { 100 struct g_consumer *cp; 101 struct g_event *event; 102 struct g_vfs_softc *sc; 103 struct buf *bp; 104 int destroy; 105 struct mount *mp; 106 struct vnode *vp; 107 struct cdev *cdevp; 108 109 /* 110 * Collect statistics on synchronous and asynchronous read 111 * and write counts for disks that have associated filesystems. 112 */ 113 bp = bip->bio_caller2; 114 vp = bp->b_vp; 115 if (vp != NULL) { 116 /* 117 * If not a disk vnode, use its associated mount point 118 * otherwise use the mountpoint associated with the disk. 119 */ 120 VI_LOCK(vp); 121 if (vp->v_type != VCHR || 122 (cdevp = vp->v_rdev) == NULL || 123 cdevp->si_devsw == NULL || 124 (cdevp->si_devsw->d_flags & D_DISK) == 0) 125 mp = vp->v_mount; 126 else 127 mp = cdevp->si_mountpt; 128 if (mp != NULL) { 129 if (bp->b_iocmd == BIO_READ) { 130 if (LK_HOLDER(bp->b_lock.lk_lock) == LK_KERNPROC) 131 mp->mnt_stat.f_asyncreads++; 132 else 133 mp->mnt_stat.f_syncreads++; 134 } else if (bp->b_iocmd == BIO_WRITE) { 135 if (LK_HOLDER(bp->b_lock.lk_lock) == LK_KERNPROC) 136 mp->mnt_stat.f_asyncwrites++; 137 else 138 mp->mnt_stat.f_syncwrites++; 139 } 140 } 141 VI_UNLOCK(vp); 142 } 143 144 cp = bip->bio_from; 145 sc = cp->geom->softc; 146 if (bip->bio_error != 0 && bip->bio_error != EOPNOTSUPP) { 147 if ((bp->b_xflags & BX_CVTENXIO) != 0) { 148 if (atomic_cmpset_int(&sc->sc_enxio_active, 0, 1)) 149 printf("g_vfs_done(): %s converting all errors to ENXIO\n", 150 bip->bio_to->name); 151 } 152 if (sc->sc_enxio_active) 153 bip->bio_error = ENXIO; 154 if (bip->bio_error != ENXIO || 155 atomic_cmpset_int(&sc->sc_enxio_reported, 0, 1)) { 156 g_print_bio("g_vfs_done():", bip, "error = %d%s", 157 bip->bio_error, 158 bip->bio_error != ENXIO ? "" : 159 " supressing further ENXIO"); 160 } 161 } 162 bp->b_error = bip->bio_error; 163 bp->b_ioflags = bip->bio_flags; 164 if (bip->bio_error) 165 bp->b_ioflags |= BIO_ERROR; 166 bp->b_resid = bp->b_bcount - bip->bio_completed; 167 g_destroy_bio(bip); 168 169 mtx_lock(&sc->sc_mtx); 170 destroy = ((--sc->sc_active) == 0 && sc->sc_orphaned); 171 if (destroy) { 172 event = sc->sc_event; 173 sc->sc_event = NULL; 174 } else 175 event = NULL; 176 mtx_unlock(&sc->sc_mtx); 177 if (destroy) 178 g_post_event_ep(g_vfs_destroy, cp, event, NULL); 179 180 bufdone(bp); 181 } 182 183 void 184 g_vfs_strategy(struct bufobj *bo, struct buf *bp) 185 { 186 struct g_vfs_softc *sc; 187 struct g_consumer *cp; 188 struct bio *bip; 189 190 cp = bo->bo_private; 191 sc = cp->geom->softc; 192 193 /* 194 * If the provider has orphaned us, just return ENXIO. 195 */ 196 mtx_lock(&sc->sc_mtx); 197 if (sc->sc_orphaned || sc->sc_enxio_active) { 198 mtx_unlock(&sc->sc_mtx); 199 bp->b_error = ENXIO; 200 bp->b_ioflags |= BIO_ERROR; 201 bufdone(bp); 202 return; 203 } 204 sc->sc_active++; 205 mtx_unlock(&sc->sc_mtx); 206 207 bip = g_alloc_bio(); 208 bip->bio_cmd = bp->b_iocmd; 209 bip->bio_offset = bp->b_iooffset; 210 bip->bio_length = bp->b_bcount; 211 bdata2bio(bp, bip); 212 if ((bp->b_flags & B_BARRIER) != 0) { 213 bip->bio_flags |= BIO_ORDERED; 214 bp->b_flags &= ~B_BARRIER; 215 } 216 if (bp->b_iocmd == BIO_SPEEDUP) 217 bip->bio_flags |= bp->b_ioflags; 218 bip->bio_done = g_vfs_done; 219 bip->bio_caller2 = bp; 220 #if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING) 221 buf_track(bp, __func__); 222 bip->bio_track_bp = bp; 223 #endif 224 g_io_request(bip, cp); 225 } 226 227 static void 228 g_vfs_orphan(struct g_consumer *cp) 229 { 230 struct g_geom *gp; 231 struct g_event *event; 232 struct g_vfs_softc *sc; 233 int destroy; 234 235 g_topology_assert(); 236 237 gp = cp->geom; 238 g_trace(G_T_TOPOLOGY, "g_vfs_orphan(%p(%s))", cp, gp->name); 239 sc = gp->softc; 240 if (sc == NULL) 241 return; 242 event = g_alloc_event(M_WAITOK); 243 mtx_lock(&sc->sc_mtx); 244 KASSERT(sc->sc_event == NULL, ("g_vfs %p already has an event", sc)); 245 sc->sc_orphaned = true; 246 destroy = (sc->sc_active == 0); 247 if (!destroy) { 248 sc->sc_event = event; 249 event = NULL; 250 } 251 mtx_unlock(&sc->sc_mtx); 252 if (destroy) { 253 g_free(event); 254 g_vfs_destroy(cp, 0); 255 } 256 257 /* 258 * Do not destroy the geom. Filesystem will do that during unmount. 259 */ 260 } 261 262 int 263 g_vfs_open(struct vnode *vp, struct g_consumer **cpp, const char *fsname, int wr) 264 { 265 struct g_geom *gp; 266 struct g_provider *pp; 267 struct g_consumer *cp; 268 struct g_vfs_softc *sc; 269 struct bufobj *bo; 270 int error; 271 272 g_topology_assert(); 273 274 *cpp = NULL; 275 bo = &vp->v_bufobj; 276 if (bo->bo_private != vp) 277 return (EBUSY); 278 279 pp = g_dev_getprovider(vp->v_rdev); 280 if (pp == NULL) 281 return (ENOENT); 282 gp = g_new_geomf(&g_vfs_class, "%s.%s", fsname, pp->name); 283 sc = g_malloc(sizeof(*sc), M_WAITOK | M_ZERO); 284 mtx_init(&sc->sc_mtx, "g_vfs", NULL, MTX_DEF); 285 sc->sc_bo = bo; 286 gp->softc = sc; 287 cp = g_new_consumer(gp); 288 error = g_attach(cp, pp); 289 if (error) { 290 g_wither_geom(gp, ENXIO); 291 return (error); 292 } 293 error = g_access(cp, 1, wr, wr); 294 if (error) { 295 g_wither_geom(gp, ENXIO); 296 return (error); 297 } 298 vnode_create_vobject(vp, pp->mediasize, curthread); 299 *cpp = cp; 300 cp->private = vp; 301 cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE; 302 bo->bo_ops = g_vfs_bufops; 303 bo->bo_private = cp; 304 bo->bo_bsize = pp->sectorsize; 305 306 return (error); 307 } 308 309 void 310 g_vfs_close(struct g_consumer *cp) 311 { 312 struct g_geom *gp; 313 struct g_vfs_softc *sc; 314 315 g_topology_assert(); 316 317 gp = cp->geom; 318 sc = gp->softc; 319 bufobj_invalbuf(sc->sc_bo, V_SAVE, 0, 0); 320 sc->sc_bo->bo_private = cp->private; 321 gp->softc = NULL; 322 mtx_destroy(&sc->sc_mtx); 323 if (!sc->sc_orphaned || cp->provider == NULL) 324 g_wither_geom_close(gp, ENXIO); 325 KASSERT(sc->sc_event == NULL, ("g_vfs %p event is non-NULL", sc)); 326 g_free(sc); 327 } 328