1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 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/param.h> 30 #include <sys/systm.h> 31 #include <sys/bio.h> 32 #include <sys/kernel.h> 33 #include <sys/lock.h> 34 #include <sys/malloc.h> 35 #include <sys/mutex.h> 36 #include <sys/sbuf.h> 37 #include <sys/vnode.h> 38 #include <sys/mount.h> 39 40 #include <geom/geom.h> 41 #include <geom/geom_vfs.h> 42 43 /* 44 * subroutines for use by filesystems. 45 * 46 * XXX: should maybe live somewhere else ? 47 */ 48 #include <sys/buf.h> 49 50 struct g_vfs_softc { 51 struct mtx sc_mtx; 52 struct bufobj *sc_bo; 53 struct g_event *sc_event; 54 int sc_active; 55 bool sc_orphaned; 56 int sc_enxio_active; 57 int sc_enxio_reported; 58 }; 59 60 static struct buf_ops __g_vfs_bufops = { 61 .bop_name = "GEOM_VFS", 62 .bop_write = bufwrite, 63 .bop_strategy = g_vfs_strategy, 64 .bop_sync = bufsync, 65 .bop_bdflush = bufbdflush 66 }; 67 68 struct buf_ops *g_vfs_bufops = &__g_vfs_bufops; 69 70 static g_orphan_t g_vfs_orphan; 71 72 static struct g_class g_vfs_class = { 73 .name = "VFS", 74 .version = G_VERSION, 75 .orphan = g_vfs_orphan, 76 }; 77 78 DECLARE_GEOM_CLASS(g_vfs_class, g_vfs); 79 80 static void 81 g_vfs_destroy(void *arg, int flags __unused) 82 { 83 struct g_consumer *cp; 84 85 g_topology_assert(); 86 cp = arg; 87 if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0) 88 g_access(cp, -cp->acr, -cp->acw, -cp->ace); 89 g_detach(cp); 90 if (cp->geom->softc == NULL) 91 g_wither_geom(cp->geom, ENXIO); 92 } 93 94 static void 95 g_vfs_done(struct bio *bip) 96 { 97 struct g_consumer *cp; 98 struct g_event *event; 99 struct g_vfs_softc *sc; 100 struct buf *bp; 101 int destroy; 102 struct mount *mp; 103 struct vnode *vp; 104 struct cdev *cdevp; 105 106 /* 107 * Collect statistics on synchronous and asynchronous read 108 * and write counts for disks that have associated filesystems. 109 */ 110 bp = bip->bio_caller2; 111 vp = bp->b_vp; 112 if (vp != NULL) { 113 /* 114 * If not a disk vnode, use its associated mount point 115 * otherwise use the mountpoint associated with the disk. 116 */ 117 VI_LOCK(vp); 118 if (vp->v_type != VCHR || 119 (cdevp = vp->v_rdev) == NULL || 120 cdevp->si_devsw == NULL || 121 (cdevp->si_devsw->d_flags & D_DISK) == 0) 122 mp = vp->v_mount; 123 else 124 mp = cdevp->si_mountpt; 125 if (mp != NULL) { 126 if (bp->b_iocmd == BIO_READ) { 127 if (LK_HOLDER(bp->b_lock.lk_lock) == LK_KERNPROC) 128 mp->mnt_stat.f_asyncreads++; 129 else 130 mp->mnt_stat.f_syncreads++; 131 } else if (bp->b_iocmd == BIO_WRITE) { 132 if (LK_HOLDER(bp->b_lock.lk_lock) == LK_KERNPROC) 133 mp->mnt_stat.f_asyncwrites++; 134 else 135 mp->mnt_stat.f_syncwrites++; 136 } 137 } 138 VI_UNLOCK(vp); 139 } 140 141 cp = bip->bio_from; 142 sc = cp->geom->softc; 143 if (bip->bio_error != 0 && bip->bio_error != EOPNOTSUPP) { 144 if ((bp->b_xflags & BX_CVTENXIO) != 0) { 145 if (atomic_cmpset_int(&sc->sc_enxio_active, 0, 1)) 146 printf("g_vfs_done(): %s converting all errors to ENXIO\n", 147 bip->bio_to->name); 148 } 149 if (sc->sc_enxio_active) 150 bip->bio_error = ENXIO; 151 if (bip->bio_error != ENXIO || 152 atomic_cmpset_int(&sc->sc_enxio_reported, 0, 1)) { 153 g_print_bio("g_vfs_done():", bip, "error = %d%s", 154 bip->bio_error, 155 bip->bio_error != ENXIO ? "" : 156 " supressing further ENXIO"); 157 } 158 } 159 bp->b_error = bip->bio_error; 160 bp->b_ioflags = bip->bio_flags; 161 if (bip->bio_error) 162 bp->b_ioflags |= BIO_ERROR; 163 bp->b_resid = bp->b_bcount - bip->bio_completed; 164 g_destroy_bio(bip); 165 166 mtx_lock(&sc->sc_mtx); 167 destroy = ((--sc->sc_active) == 0 && sc->sc_orphaned); 168 if (destroy) { 169 event = sc->sc_event; 170 sc->sc_event = NULL; 171 } else 172 event = NULL; 173 mtx_unlock(&sc->sc_mtx); 174 if (destroy) 175 g_post_event_ep(g_vfs_destroy, cp, event, NULL); 176 177 bufdone(bp); 178 } 179 180 void 181 g_vfs_strategy(struct bufobj *bo, struct buf *bp) 182 { 183 struct g_vfs_softc *sc; 184 struct g_consumer *cp; 185 struct bio *bip; 186 187 cp = bo->bo_private; 188 sc = cp->geom->softc; 189 190 /* 191 * If the provider has orphaned us, just return ENXIO. 192 */ 193 mtx_lock(&sc->sc_mtx); 194 if (sc->sc_orphaned || sc->sc_enxio_active) { 195 mtx_unlock(&sc->sc_mtx); 196 bp->b_error = ENXIO; 197 bp->b_ioflags |= BIO_ERROR; 198 bufdone(bp); 199 return; 200 } 201 sc->sc_active++; 202 mtx_unlock(&sc->sc_mtx); 203 204 bip = g_alloc_bio(); 205 bip->bio_cmd = bp->b_iocmd; 206 bip->bio_offset = bp->b_iooffset; 207 bip->bio_length = bp->b_bcount; 208 bdata2bio(bp, bip); 209 if ((bp->b_flags & B_BARRIER) != 0) { 210 bip->bio_flags |= BIO_ORDERED; 211 bp->b_flags &= ~B_BARRIER; 212 } 213 if (bp->b_iocmd == BIO_SPEEDUP) 214 bip->bio_flags |= bp->b_ioflags; 215 bip->bio_done = g_vfs_done; 216 bip->bio_caller2 = bp; 217 #if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING) 218 buf_track(bp, __func__); 219 bip->bio_track_bp = bp; 220 #endif 221 g_io_request(bip, cp); 222 } 223 224 static void 225 g_vfs_orphan(struct g_consumer *cp) 226 { 227 struct g_geom *gp; 228 struct g_event *event; 229 struct g_vfs_softc *sc; 230 int destroy; 231 232 g_topology_assert(); 233 234 gp = cp->geom; 235 g_trace(G_T_TOPOLOGY, "g_vfs_orphan(%p(%s))", cp, gp->name); 236 sc = gp->softc; 237 if (sc == NULL) 238 return; 239 event = g_alloc_event(M_WAITOK); 240 mtx_lock(&sc->sc_mtx); 241 KASSERT(sc->sc_event == NULL, ("g_vfs %p already has an event", sc)); 242 sc->sc_orphaned = true; 243 destroy = (sc->sc_active == 0); 244 if (!destroy) { 245 sc->sc_event = event; 246 event = NULL; 247 } 248 mtx_unlock(&sc->sc_mtx); 249 if (destroy) { 250 g_free(event); 251 g_vfs_destroy(cp, 0); 252 } 253 254 /* 255 * Do not destroy the geom. Filesystem will do that during unmount. 256 */ 257 } 258 259 int 260 g_vfs_open(struct vnode *vp, struct g_consumer **cpp, const char *fsname, int wr) 261 { 262 struct g_geom *gp; 263 struct g_provider *pp; 264 struct g_consumer *cp; 265 struct g_vfs_softc *sc; 266 struct bufobj *bo; 267 int error; 268 269 g_topology_assert(); 270 271 *cpp = NULL; 272 bo = &vp->v_bufobj; 273 if (bo->bo_private != vp) 274 return (EBUSY); 275 276 pp = g_dev_getprovider(vp->v_rdev); 277 if (pp == NULL) 278 return (ENOENT); 279 gp = g_new_geomf(&g_vfs_class, "%s.%s", fsname, pp->name); 280 sc = g_malloc(sizeof(*sc), M_WAITOK | M_ZERO); 281 mtx_init(&sc->sc_mtx, "g_vfs", NULL, MTX_DEF); 282 sc->sc_bo = bo; 283 gp->softc = sc; 284 cp = g_new_consumer(gp); 285 error = g_attach(cp, pp); 286 if (error) { 287 g_wither_geom(gp, ENXIO); 288 return (error); 289 } 290 error = g_access(cp, 1, wr, wr); 291 if (error) { 292 g_wither_geom(gp, ENXIO); 293 return (error); 294 } 295 vnode_create_vobject(vp, pp->mediasize, curthread); 296 *cpp = cp; 297 cp->private = vp; 298 cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE; 299 bo->bo_ops = g_vfs_bufops; 300 bo->bo_private = cp; 301 bo->bo_bsize = pp->sectorsize; 302 303 return (error); 304 } 305 306 void 307 g_vfs_close(struct g_consumer *cp) 308 { 309 struct g_geom *gp; 310 struct g_vfs_softc *sc; 311 312 g_topology_assert(); 313 314 gp = cp->geom; 315 sc = gp->softc; 316 bufobj_invalbuf(sc->sc_bo, V_SAVE, 0, 0); 317 sc->sc_bo->bo_private = cp->private; 318 gp->softc = NULL; 319 mtx_destroy(&sc->sc_mtx); 320 if (!sc->sc_orphaned || cp->provider == NULL) 321 g_wither_geom_close(gp, ENXIO); 322 KASSERT(sc->sc_event == NULL, ("g_vfs %p event is non-NULL", sc)); 323 g_free(sc); 324 } 325