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