1 /*- 2 * Copyright (c) 2004 Poul-Henning Kamp 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <sys/param.h> 31 #include <sys/systm.h> 32 #include <sys/bio.h> 33 #include <sys/kernel.h> 34 #include <sys/lock.h> 35 #include <sys/malloc.h> 36 #include <sys/mutex.h> 37 #include <sys/vnode.h> 38 #include <sys/mount.h> /* XXX Temporary for VFS_LOCK_GIANT */ 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 int sc_active; 54 int sc_orphaned; 55 }; 56 57 static struct buf_ops __g_vfs_bufops = { 58 .bop_name = "GEOM_VFS", 59 .bop_write = bufwrite, 60 .bop_strategy = g_vfs_strategy, 61 .bop_sync = bufsync, 62 .bop_bdflush = bufbdflush 63 }; 64 65 struct buf_ops *g_vfs_bufops = &__g_vfs_bufops; 66 67 static g_orphan_t g_vfs_orphan; 68 69 static struct g_class g_vfs_class = { 70 .name = "VFS", 71 .version = G_VERSION, 72 .orphan = g_vfs_orphan, 73 }; 74 75 DECLARE_GEOM_CLASS(g_vfs_class, g_vfs); 76 77 static void 78 g_vfs_destroy(void *arg, int flags __unused) 79 { 80 struct g_consumer *cp; 81 82 g_topology_assert(); 83 cp = arg; 84 if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0) 85 g_access(cp, -cp->acr, -cp->acw, -cp->ace); 86 g_detach(cp); 87 if (cp->geom->softc == NULL) 88 g_wither_geom(cp->geom, ENXIO); 89 } 90 91 static void 92 g_vfs_done(struct bio *bip) 93 { 94 struct g_consumer *cp; 95 struct g_vfs_softc *sc; 96 struct buf *bp; 97 int vfslocked, destroy; 98 struct mount *mp; 99 struct vnode *vp; 100 struct cdev *cdevp; 101 102 /* 103 * Collect statistics on synchronous and asynchronous read 104 * and write counts for disks that have associated filesystems. 105 * Since this run by the g_up thread it is single threaded and 106 * we do not need to use atomic increments on the counters. 107 */ 108 bp = bip->bio_caller2; 109 vp = bp->b_vp; 110 if (vp == NULL) { 111 mp = NULL; 112 } else { 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 VI_UNLOCK(vp); 126 } 127 if (mp != NULL) { 128 if (bp->b_iocmd == BIO_WRITE) { 129 if (LK_HOLDER(bp->b_lock.lk_lock) == LK_KERNPROC) 130 mp->mnt_stat.f_asyncwrites++; 131 else 132 mp->mnt_stat.f_syncwrites++; 133 } else { 134 if (LK_HOLDER(bp->b_lock.lk_lock) == LK_KERNPROC) 135 mp->mnt_stat.f_asyncreads++; 136 else 137 mp->mnt_stat.f_syncreads++; 138 } 139 } 140 141 cp = bip->bio_from; 142 sc = cp->geom->softc; 143 if (bip->bio_error) { 144 printf("g_vfs_done():"); 145 g_print_bio(bip); 146 printf("error = %d\n", bip->bio_error); 147 } 148 bp->b_error = bip->bio_error; 149 bp->b_ioflags = bip->bio_flags; 150 if (bip->bio_error) 151 bp->b_ioflags |= BIO_ERROR; 152 bp->b_resid = bp->b_bcount - bip->bio_completed; 153 g_destroy_bio(bip); 154 155 mtx_lock(&sc->sc_mtx); 156 destroy = ((--sc->sc_active) == 0 && sc->sc_orphaned); 157 mtx_unlock(&sc->sc_mtx); 158 if (destroy) 159 g_post_event(g_vfs_destroy, cp, M_WAITOK, NULL); 160 161 vfslocked = VFS_LOCK_GIANT(((struct mount *)NULL)); 162 bufdone(bp); 163 VFS_UNLOCK_GIANT(vfslocked); 164 } 165 166 void 167 g_vfs_strategy(struct bufobj *bo, struct buf *bp) 168 { 169 struct g_vfs_softc *sc; 170 struct g_consumer *cp; 171 struct bio *bip; 172 int vfslocked; 173 174 cp = bo->bo_private; 175 sc = cp->geom->softc; 176 177 /* 178 * If the provider has orphaned us, just return EXIO. 179 */ 180 mtx_lock(&sc->sc_mtx); 181 if (sc->sc_orphaned) { 182 mtx_unlock(&sc->sc_mtx); 183 bp->b_error = ENXIO; 184 bp->b_ioflags |= BIO_ERROR; 185 vfslocked = VFS_LOCK_GIANT(((struct mount *)NULL)); 186 bufdone(bp); 187 VFS_UNLOCK_GIANT(vfslocked); 188 return; 189 } 190 sc->sc_active++; 191 mtx_unlock(&sc->sc_mtx); 192 193 bip = g_alloc_bio(); 194 bip->bio_cmd = bp->b_iocmd; 195 bip->bio_offset = bp->b_iooffset; 196 bip->bio_data = bp->b_data; 197 bip->bio_done = g_vfs_done; 198 bip->bio_caller2 = bp; 199 bip->bio_length = bp->b_bcount; 200 g_io_request(bip, cp); 201 } 202 203 static void 204 g_vfs_orphan(struct g_consumer *cp) 205 { 206 struct g_geom *gp; 207 struct g_vfs_softc *sc; 208 int destroy; 209 210 g_topology_assert(); 211 212 gp = cp->geom; 213 g_trace(G_T_TOPOLOGY, "g_vfs_orphan(%p(%s))", cp, gp->name); 214 sc = gp->softc; 215 if (sc == NULL) 216 return; 217 mtx_lock(&sc->sc_mtx); 218 sc->sc_orphaned = 1; 219 destroy = (sc->sc_active == 0); 220 mtx_unlock(&sc->sc_mtx); 221 if (destroy) 222 g_vfs_destroy(cp, 0); 223 224 /* 225 * Do not destroy the geom. Filesystem will do that during unmount. 226 */ 227 } 228 229 int 230 g_vfs_open(struct vnode *vp, struct g_consumer **cpp, const char *fsname, int wr) 231 { 232 struct g_geom *gp; 233 struct g_provider *pp; 234 struct g_consumer *cp; 235 struct g_vfs_softc *sc; 236 struct bufobj *bo; 237 int vfslocked; 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 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 263 vnode_create_vobject(vp, pp->mediasize, curthread); 264 VFS_UNLOCK_GIANT(vfslocked); 265 *cpp = cp; 266 cp->private = vp; 267 bo->bo_ops = g_vfs_bufops; 268 bo->bo_private = cp; 269 bo->bo_bsize = pp->sectorsize; 270 271 return (error); 272 } 273 274 void 275 g_vfs_close(struct g_consumer *cp) 276 { 277 struct g_geom *gp; 278 struct g_vfs_softc *sc; 279 280 g_topology_assert(); 281 282 gp = cp->geom; 283 sc = gp->softc; 284 bufobj_invalbuf(sc->sc_bo, V_SAVE, 0, 0); 285 sc->sc_bo->bo_private = cp->private; 286 gp->softc = NULL; 287 mtx_destroy(&sc->sc_mtx); 288 if (!sc->sc_orphaned || cp->provider == NULL) 289 g_wither_geom_close(gp, ENXIO); 290 g_free(sc); 291 } 292