mfs_vfsops.c revision 1.88
1 /* $NetBSD: mfs_vfsops.c,v 1.88 2008/01/28 14:31:21 dholland Exp $ */ 2 3 /* 4 * Copyright (c) 1989, 1990, 1993, 1994 5 * The Regents of the University of California. 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 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)mfs_vfsops.c 8.11 (Berkeley) 6/19/95 32 */ 33 34 #include <sys/cdefs.h> 35 __KERNEL_RCSID(0, "$NetBSD: mfs_vfsops.c,v 1.88 2008/01/28 14:31:21 dholland Exp $"); 36 37 #if defined(_KERNEL_OPT) 38 #include "opt_compat_netbsd.h" 39 #endif 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/sysctl.h> 44 #include <sys/time.h> 45 #include <sys/kernel.h> 46 #include <sys/proc.h> 47 #include <sys/buf.h> 48 #include <sys/bufq.h> 49 #include <sys/mount.h> 50 #include <sys/signalvar.h> 51 #include <sys/vnode.h> 52 #include <sys/malloc.h> 53 54 #include <miscfs/genfs/genfs.h> 55 #include <miscfs/specfs/specdev.h> 56 #include <miscfs/syncfs/syncfs.h> 57 58 #include <ufs/ufs/quota.h> 59 #include <ufs/ufs/inode.h> 60 #include <ufs/ufs/ufsmount.h> 61 #include <ufs/ufs/ufs_extern.h> 62 63 #include <ufs/ffs/fs.h> 64 #include <ufs/ffs/ffs_extern.h> 65 66 #include <ufs/mfs/mfsnode.h> 67 #include <ufs/mfs/mfs_extern.h> 68 69 void * mfs_rootbase; /* address of mini-root in kernel virtual memory */ 70 u_long mfs_rootsize; /* size of mini-root in bytes */ 71 72 static int mfs_minor; /* used for building internal dev_t */ 73 74 extern int (**mfs_vnodeop_p)(void *); 75 76 MALLOC_JUSTDEFINE(M_MFSNODE, "MFS node", "MFS vnode private part"); 77 78 /* 79 * mfs vfs operations. 80 */ 81 82 extern const struct vnodeopv_desc mfs_vnodeop_opv_desc; 83 84 const struct vnodeopv_desc * const mfs_vnodeopv_descs[] = { 85 &mfs_vnodeop_opv_desc, 86 NULL, 87 }; 88 89 struct vfsops mfs_vfsops = { 90 MOUNT_MFS, 91 sizeof (struct mfs_args), 92 mfs_mount, 93 mfs_start, 94 ffs_unmount, 95 ufs_root, 96 ufs_quotactl, 97 mfs_statvfs, 98 ffs_sync, 99 ffs_vget, 100 ffs_fhtovp, 101 ffs_vptofh, 102 mfs_init, 103 mfs_reinit, 104 mfs_done, 105 NULL, 106 (int (*)(struct mount *, struct vnode *, struct timespec *)) eopnotsupp, 107 vfs_stdextattrctl, 108 (void *)eopnotsupp, /* vfs_suspendctl */ 109 genfs_renamelock_enter, 110 genfs_renamelock_exit, 111 mfs_vnodeopv_descs, 112 0, 113 { NULL, NULL }, 114 }; 115 VFS_ATTACH(mfs_vfsops); 116 117 SYSCTL_SETUP(sysctl_vfs_mfs_setup, "sysctl vfs.mfs subtree setup") 118 { 119 120 sysctl_createv(clog, 0, NULL, NULL, 121 CTLFLAG_PERMANENT, 122 CTLTYPE_NODE, "vfs", NULL, 123 NULL, 0, NULL, 0, 124 CTL_VFS, CTL_EOL); 125 sysctl_createv(clog, 0, NULL, NULL, 126 CTLFLAG_PERMANENT|CTLFLAG_ALIAS, 127 CTLTYPE_NODE, "mfs", 128 SYSCTL_DESCR("Memory based file system"), 129 NULL, 1, NULL, 0, 130 CTL_VFS, 3, CTL_EOL); 131 /* 132 * XXX the "1" and the "3" above could be dynamic, thereby 133 * eliminating one more instance of the "number to vfs" 134 * mapping problem, but they are in order as taken from 135 * sys/mount.h 136 */ 137 } 138 139 /* 140 * Memory based filesystem initialization. 141 */ 142 void 143 mfs_init(void) 144 { 145 146 malloc_type_attach(M_MFSNODE); 147 /* 148 * ffs_init() ensures to initialize necessary resources 149 * only once. 150 */ 151 ffs_init(); 152 } 153 154 void 155 mfs_reinit(void) 156 { 157 ffs_reinit(); 158 } 159 160 void 161 mfs_done(void) 162 { 163 /* 164 * ffs_done() ensures to free necessary resources 165 * only once, when it's no more needed. 166 */ 167 ffs_done(); 168 malloc_type_detach(M_MFSNODE); 169 } 170 171 /* 172 * Called by main() when mfs is going to be mounted as root. 173 */ 174 175 int 176 mfs_mountroot(void) 177 { 178 struct fs *fs; 179 struct mount *mp; 180 struct lwp *l = curlwp; /* XXX */ 181 struct ufsmount *ump; 182 struct mfsnode *mfsp; 183 int error = 0; 184 185 if ((error = vfs_rootmountalloc(MOUNT_MFS, "mfs_root", &mp))) { 186 vrele(rootvp); 187 return (error); 188 } 189 190 mfsp = malloc(sizeof *mfsp, M_MFSNODE, M_WAITOK); 191 rootvp->v_data = mfsp; 192 rootvp->v_op = mfs_vnodeop_p; 193 rootvp->v_tag = VT_MFS; 194 mfsp->mfs_baseoff = mfs_rootbase; 195 mfsp->mfs_size = mfs_rootsize; 196 mfsp->mfs_vnode = rootvp; 197 mfsp->mfs_proc = NULL; /* indicate kernel space */ 198 mfsp->mfs_shutdown = 0; 199 bufq_alloc(&mfsp->mfs_buflist, "fcfs", 0); 200 if ((error = ffs_mountfs(rootvp, mp, l)) != 0) { 201 mp->mnt_op->vfs_refcount--; 202 vfs_unbusy(mp); 203 bufq_free(mfsp->mfs_buflist); 204 vfs_destroy(mp); 205 free(mfsp, M_MFSNODE); 206 return (error); 207 } 208 mutex_enter(&mountlist_lock); 209 CIRCLEQ_INSERT_TAIL(&mountlist, mp, mnt_list); 210 mutex_exit(&mountlist_lock); 211 mp->mnt_vnodecovered = NULLVP; 212 ump = VFSTOUFS(mp); 213 fs = ump->um_fs; 214 (void) copystr(mp->mnt_stat.f_mntonname, fs->fs_fsmnt, MNAMELEN - 1, 0); 215 (void)ffs_statvfs(mp, &mp->mnt_stat); 216 vfs_unbusy(mp); 217 return (0); 218 } 219 220 /* 221 * This is called early in boot to set the base address and size 222 * of the mini-root. 223 */ 224 int 225 mfs_initminiroot(void *base) 226 { 227 struct fs *fs = (struct fs *)((char *)base + SBLOCK_UFS1); 228 229 /* check for valid super block */ 230 if (fs->fs_magic != FS_UFS1_MAGIC || fs->fs_bsize > MAXBSIZE || 231 fs->fs_bsize < sizeof(struct fs)) 232 return (0); 233 mountroot = mfs_mountroot; 234 mfs_rootbase = base; 235 mfs_rootsize = fs->fs_fsize * fs->fs_size; 236 rootdev = makedev(255, mfs_minor); 237 mfs_minor++; 238 return (mfs_rootsize); 239 } 240 241 /* 242 * VFS Operations. 243 * 244 * mount system call 245 */ 246 /* ARGSUSED */ 247 int 248 mfs_mount(struct mount *mp, const char *path, void *data, size_t *data_len) 249 { 250 struct lwp *l = curlwp; 251 struct vnode *devvp; 252 struct mfs_args *args = data; 253 struct ufsmount *ump; 254 struct fs *fs; 255 struct mfsnode *mfsp; 256 struct proc *p; 257 int flags, error = 0; 258 259 if (*data_len < sizeof *args) 260 return EINVAL; 261 262 p = l->l_proc; 263 if (mp->mnt_flag & MNT_GETARGS) { 264 struct vnode *vp; 265 266 ump = VFSTOUFS(mp); 267 if (ump == NULL) 268 return EIO; 269 270 vp = ump->um_devvp; 271 if (vp == NULL) 272 return EIO; 273 274 mfsp = VTOMFS(vp); 275 if (mfsp == NULL) 276 return EIO; 277 278 args->fspec = NULL; 279 args->base = mfsp->mfs_baseoff; 280 args->size = mfsp->mfs_size; 281 *data_len = sizeof *args; 282 return 0; 283 } 284 /* 285 * XXX turn off async to avoid hangs when writing lots of data. 286 * the problem is that MFS needs to allocate pages to clean pages, 287 * so if we wait until the last minute to clean pages then there 288 * may not be any pages available to do the cleaning. 289 * ... and since the default partially-synchronous mode turns out 290 * to not be sufficient under heavy load, make it full synchronous. 291 */ 292 mp->mnt_flag &= ~MNT_ASYNC; 293 mp->mnt_flag |= MNT_SYNCHRONOUS; 294 295 /* 296 * If updating, check whether changing from read-only to 297 * read/write; if there is no device name, that's all we do. 298 */ 299 if (mp->mnt_flag & MNT_UPDATE) { 300 ump = VFSTOUFS(mp); 301 fs = ump->um_fs; 302 if (fs->fs_ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) { 303 flags = WRITECLOSE; 304 if (mp->mnt_flag & MNT_FORCE) 305 flags |= FORCECLOSE; 306 error = ffs_flushfiles(mp, flags, l); 307 if (error) 308 return (error); 309 } 310 if (fs->fs_ronly && (mp->mnt_iflag & IMNT_WANTRDWR)) 311 fs->fs_ronly = 0; 312 if (args->fspec == NULL) 313 return EINVAL; 314 return (0); 315 } 316 error = getnewvnode(VT_MFS, (struct mount *)0, mfs_vnodeop_p, &devvp); 317 if (error) 318 return (error); 319 devvp->v_type = VBLK; 320 spec_node_init(devvp, makedev(255, mfs_minor)); 321 mfs_minor++; 322 mfsp = (struct mfsnode *)malloc(sizeof *mfsp, M_MFSNODE, M_WAITOK); 323 devvp->v_data = mfsp; 324 mfsp->mfs_baseoff = args->base; 325 mfsp->mfs_size = args->size; 326 mfsp->mfs_vnode = devvp; 327 mfsp->mfs_proc = p; 328 mfsp->mfs_shutdown = 0; 329 bufq_alloc(&mfsp->mfs_buflist, "fcfs", 0); 330 if ((error = ffs_mountfs(devvp, mp, l)) != 0) { 331 mfsp->mfs_shutdown = 1; 332 vrele(devvp); 333 return (error); 334 } 335 ump = VFSTOUFS(mp); 336 fs = ump->um_fs; 337 error = set_statvfs_info(path, UIO_USERSPACE, args->fspec, 338 UIO_USERSPACE, mp->mnt_op->vfs_name, mp, l); 339 if (error) 340 return error; 341 (void)strncpy(fs->fs_fsmnt, mp->mnt_stat.f_mntonname, 342 sizeof(fs->fs_fsmnt)); 343 fs->fs_fsmnt[sizeof(fs->fs_fsmnt) - 1] = '\0'; 344 /* XXX: cleanup on error */ 345 return 0; 346 } 347 348 int mfs_pri = PWAIT | PCATCH; /* XXX prob. temp */ 349 350 /* 351 * Used to grab the process and keep it in the kernel to service 352 * memory filesystem I/O requests. 353 * 354 * Loop servicing I/O requests. 355 * Copy the requested data into or out of the memory filesystem 356 * address space. 357 */ 358 /* ARGSUSED */ 359 int 360 mfs_start(struct mount *mp, int flags) 361 { 362 struct lwp *l = curlwp; 363 struct vnode *vp = VFSTOUFS(mp)->um_devvp; 364 struct mfsnode *mfsp = VTOMFS(vp); 365 struct proc *p; 366 struct buf *bp; 367 void *base; 368 int sleepreturn = 0; 369 ksiginfoq_t kq; 370 371 base = mfsp->mfs_baseoff; 372 while (mfsp->mfs_shutdown != 1) { 373 while ((bp = BUFQ_GET(mfsp->mfs_buflist)) != NULL) { 374 mfs_doio(bp, base); 375 wakeup((void *)bp); 376 } 377 /* 378 * If a non-ignored signal is received, try to unmount. 379 * If that fails, or the filesystem is already in the 380 * process of being unmounted, clear the signal (it has been 381 * "processed"), otherwise we will loop here, as tsleep 382 * will always return EINTR/ERESTART. 383 */ 384 if (sleepreturn != 0) { 385 /* 386 * XXX Freeze syncer. Must do this before locking 387 * the mount point. See dounmount() for details. 388 */ 389 mutex_enter(&syncer_mutex); 390 if (vfs_busy(mp, LK_NOWAIT, 0) != 0) 391 mutex_exit(&syncer_mutex); 392 else if (dounmount(mp, 0, l) != 0) { 393 p = l->l_proc; 394 ksiginfo_queue_init(&kq); 395 mutex_enter(&p->p_smutex); 396 sigclearall(p, NULL, &kq); 397 mutex_exit(&p->p_smutex); 398 ksiginfo_queue_drain(&kq); 399 } 400 sleepreturn = 0; 401 continue; 402 } 403 404 sleepreturn = tsleep(vp, mfs_pri, "mfsidl", 0); 405 } 406 KASSERT(BUFQ_PEEK(mfsp->mfs_buflist) == NULL); 407 bufq_free(mfsp->mfs_buflist); 408 return (sleepreturn); 409 } 410 411 /* 412 * Get file system statistics. 413 */ 414 int 415 mfs_statvfs(struct mount *mp, struct statvfs *sbp) 416 { 417 int error; 418 419 error = ffs_statvfs(mp, sbp); 420 if (error) 421 return error; 422 (void)strncpy(sbp->f_fstypename, mp->mnt_op->vfs_name, 423 sizeof(sbp->f_fstypename)); 424 sbp->f_fstypename[sizeof(sbp->f_fstypename) - 1] = '\0'; 425 return 0; 426 } 427
Indexes created Mon Sep 29 03:10:08 GMT 2025