mfs_vfsops.c revision 1.87
1 /* $NetBSD: mfs_vfsops.c,v 1.87 2008/01/25 10:30:20 pooka 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 1.87 2008/01/25 10:30:20 pooka 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/specfs/specdev.h> 55 #include <miscfs/syncfs/syncfs.h> 56 57 #include <ufs/ufs/quota.h> 58 #include <ufs/ufs/inode.h> 59 #include <ufs/ufs/ufsmount.h> 60 #include <ufs/ufs/ufs_extern.h> 61 62 #include <ufs/ffs/fs.h> 63 #include <ufs/ffs/ffs_extern.h> 64 65 #include <ufs/mfs/mfsnode.h> 66 #include <ufs/mfs/mfs_extern.h> 67 68 void * mfs_rootbase; /* address of mini-root in kernel virtual memory */ 69 u_long mfs_rootsize; /* size of mini-root in bytes */ 70 71 static int mfs_minor; /* used for building internal dev_t */ 72 73 extern int (**mfs_vnodeop_p)(void *); 74 75 MALLOC_JUSTDEFINE(M_MFSNODE, "MFS node", "MFS vnode private part"); 76 77 /* 78 * mfs vfs operations. 79 */ 80 81 extern const struct vnodeopv_desc mfs_vnodeop_opv_desc; 82 83 const struct vnodeopv_desc * const mfs_vnodeopv_descs[] = { 84 &mfs_vnodeop_opv_desc, 85 NULL, 86 }; 87 88 struct vfsops mfs_vfsops = { 89 MOUNT_MFS, 90 sizeof (struct mfs_args), 91 mfs_mount, 92 mfs_start, 93 ffs_unmount, 94 ufs_root, 95 ufs_quotactl, 96 mfs_statvfs, 97 ffs_sync, 98 ffs_vget, 99 ffs_fhtovp, 100 ffs_vptofh, 101 mfs_init, 102 mfs_reinit, 103 mfs_done, 104 NULL, 105 (int (*)(struct mount *, struct vnode *, struct timespec *)) eopnotsupp, 106 vfs_stdextattrctl, 107 (void *)eopnotsupp, /* vfs_suspendctl */ 108 mfs_vnodeopv_descs, 109 0, 110 { NULL, NULL }, 111 }; 112 VFS_ATTACH(mfs_vfsops); 113 114 SYSCTL_SETUP(sysctl_vfs_mfs_setup, "sysctl vfs.mfs subtree setup") 115 { 116 117 sysctl_createv(clog, 0, NULL, NULL, 118 CTLFLAG_PERMANENT, 119 CTLTYPE_NODE, "vfs", NULL, 120 NULL, 0, NULL, 0, 121 CTL_VFS, CTL_EOL); 122 sysctl_createv(clog, 0, NULL, NULL, 123 CTLFLAG_PERMANENT|CTLFLAG_ALIAS, 124 CTLTYPE_NODE, "mfs", 125 SYSCTL_DESCR("Memory based file system"), 126 NULL, 1, NULL, 0, 127 CTL_VFS, 3, CTL_EOL); 128 /* 129 * XXX the "1" and the "3" above could be dynamic, thereby 130 * eliminating one more instance of the "number to vfs" 131 * mapping problem, but they are in order as taken from 132 * sys/mount.h 133 */ 134 } 135 136 /* 137 * Memory based filesystem initialization. 138 */ 139 void 140 mfs_init(void) 141 { 142 143 malloc_type_attach(M_MFSNODE); 144 /* 145 * ffs_init() ensures to initialize necessary resources 146 * only once. 147 */ 148 ffs_init(); 149 } 150 151 void 152 mfs_reinit(void) 153 { 154 ffs_reinit(); 155 } 156 157 void 158 mfs_done(void) 159 { 160 /* 161 * ffs_done() ensures to free necessary resources 162 * only once, when it's no more needed. 163 */ 164 ffs_done(); 165 malloc_type_detach(M_MFSNODE); 166 } 167 168 /* 169 * Called by main() when mfs is going to be mounted as root. 170 */ 171 172 int 173 mfs_mountroot(void) 174 { 175 struct fs *fs; 176 struct mount *mp; 177 struct lwp *l = curlwp; /* XXX */ 178 struct ufsmount *ump; 179 struct mfsnode *mfsp; 180 int error = 0; 181 182 if ((error = vfs_rootmountalloc(MOUNT_MFS, "mfs_root", &mp))) { 183 vrele(rootvp); 184 return (error); 185 } 186 187 mfsp = malloc(sizeof *mfsp, M_MFSNODE, M_WAITOK); 188 rootvp->v_data = mfsp; 189 rootvp->v_op = mfs_vnodeop_p; 190 rootvp->v_tag = VT_MFS; 191 mfsp->mfs_baseoff = mfs_rootbase; 192 mfsp->mfs_size = mfs_rootsize; 193 mfsp->mfs_vnode = rootvp; 194 mfsp->mfs_proc = NULL; /* indicate kernel space */ 195 mfsp->mfs_shutdown = 0; 196 bufq_alloc(&mfsp->mfs_buflist, "fcfs", 0); 197 if ((error = ffs_mountfs(rootvp, mp, l)) != 0) { 198 mp->mnt_op->vfs_refcount--; 199 vfs_unbusy(mp); 200 bufq_free(mfsp->mfs_buflist); 201 vfs_destroy(mp); 202 free(mfsp, M_MFSNODE); 203 return (error); 204 } 205 mutex_enter(&mountlist_lock); 206 CIRCLEQ_INSERT_TAIL(&mountlist, mp, mnt_list); 207 mutex_exit(&mountlist_lock); 208 mp->mnt_vnodecovered = NULLVP; 209 ump = VFSTOUFS(mp); 210 fs = ump->um_fs; 211 (void) copystr(mp->mnt_stat.f_mntonname, fs->fs_fsmnt, MNAMELEN - 1, 0); 212 (void)ffs_statvfs(mp, &mp->mnt_stat); 213 vfs_unbusy(mp); 214 return (0); 215 } 216 217 /* 218 * This is called early in boot to set the base address and size 219 * of the mini-root. 220 */ 221 int 222 mfs_initminiroot(void *base) 223 { 224 struct fs *fs = (struct fs *)((char *)base + SBLOCK_UFS1); 225 226 /* check for valid super block */ 227 if (fs->fs_magic != FS_UFS1_MAGIC || fs->fs_bsize > MAXBSIZE || 228 fs->fs_bsize < sizeof(struct fs)) 229 return (0); 230 mountroot = mfs_mountroot; 231 mfs_rootbase = base; 232 mfs_rootsize = fs->fs_fsize * fs->fs_size; 233 rootdev = makedev(255, mfs_minor); 234 mfs_minor++; 235 return (mfs_rootsize); 236 } 237 238 /* 239 * VFS Operations. 240 * 241 * mount system call 242 */ 243 /* ARGSUSED */ 244 int 245 mfs_mount(struct mount *mp, const char *path, void *data, size_t *data_len) 246 { 247 struct lwp *l = curlwp; 248 struct vnode *devvp; 249 struct mfs_args *args = data; 250 struct ufsmount *ump; 251 struct fs *fs; 252 struct mfsnode *mfsp; 253 struct proc *p; 254 int flags, error = 0; 255 256 if (*data_len < sizeof *args) 257 return EINVAL; 258 259 p = l->l_proc; 260 if (mp->mnt_flag & MNT_GETARGS) { 261 struct vnode *vp; 262 263 ump = VFSTOUFS(mp); 264 if (ump == NULL) 265 return EIO; 266 267 vp = ump->um_devvp; 268 if (vp == NULL) 269 return EIO; 270 271 mfsp = VTOMFS(vp); 272 if (mfsp == NULL) 273 return EIO; 274 275 args->fspec = NULL; 276 args->base = mfsp->mfs_baseoff; 277 args->size = mfsp->mfs_size; 278 *data_len = sizeof *args; 279 return 0; 280 } 281 /* 282 * XXX turn off async to avoid hangs when writing lots of data. 283 * the problem is that MFS needs to allocate pages to clean pages, 284 * so if we wait until the last minute to clean pages then there 285 * may not be any pages available to do the cleaning. 286 * ... and since the default partially-synchronous mode turns out 287 * to not be sufficient under heavy load, make it full synchronous. 288 */ 289 mp->mnt_flag &= ~MNT_ASYNC; 290 mp->mnt_flag |= MNT_SYNCHRONOUS; 291 292 /* 293 * If updating, check whether changing from read-only to 294 * read/write; if there is no device name, that's all we do. 295 */ 296 if (mp->mnt_flag & MNT_UPDATE) { 297 ump = VFSTOUFS(mp); 298 fs = ump->um_fs; 299 if (fs->fs_ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) { 300 flags = WRITECLOSE; 301 if (mp->mnt_flag & MNT_FORCE) 302 flags |= FORCECLOSE; 303 error = ffs_flushfiles(mp, flags, l); 304 if (error) 305 return (error); 306 } 307 if (fs->fs_ronly && (mp->mnt_iflag & IMNT_WANTRDWR)) 308 fs->fs_ronly = 0; 309 if (args->fspec == NULL) 310 return EINVAL; 311 return (0); 312 } 313 error = getnewvnode(VT_MFS, (struct mount *)0, mfs_vnodeop_p, &devvp); 314 if (error) 315 return (error); 316 devvp->v_type = VBLK; 317 spec_node_init(devvp, makedev(255, mfs_minor)); 318 mfs_minor++; 319 mfsp = (struct mfsnode *)malloc(sizeof *mfsp, M_MFSNODE, M_WAITOK); 320 devvp->v_data = mfsp; 321 mfsp->mfs_baseoff = args->base; 322 mfsp->mfs_size = args->size; 323 mfsp->mfs_vnode = devvp; 324 mfsp->mfs_proc = p; 325 mfsp->mfs_shutdown = 0; 326 bufq_alloc(&mfsp->mfs_buflist, "fcfs", 0); 327 if ((error = ffs_mountfs(devvp, mp, l)) != 0) { 328 mfsp->mfs_shutdown = 1; 329 vrele(devvp); 330 return (error); 331 } 332 ump = VFSTOUFS(mp); 333 fs = ump->um_fs; 334 error = set_statvfs_info(path, UIO_USERSPACE, args->fspec, 335 UIO_USERSPACE, mp->mnt_op->vfs_name, mp, l); 336 if (error) 337 return error; 338 (void)strncpy(fs->fs_fsmnt, mp->mnt_stat.f_mntonname, 339 sizeof(fs->fs_fsmnt)); 340 fs->fs_fsmnt[sizeof(fs->fs_fsmnt) - 1] = '\0'; 341 /* XXX: cleanup on error */ 342 return 0; 343 } 344 345 int mfs_pri = PWAIT | PCATCH; /* XXX prob. temp */ 346 347 /* 348 * Used to grab the process and keep it in the kernel to service 349 * memory filesystem I/O requests. 350 * 351 * Loop servicing I/O requests. 352 * Copy the requested data into or out of the memory filesystem 353 * address space. 354 */ 355 /* ARGSUSED */ 356 int 357 mfs_start(struct mount *mp, int flags) 358 { 359 struct lwp *l = curlwp; 360 struct vnode *vp = VFSTOUFS(mp)->um_devvp; 361 struct mfsnode *mfsp = VTOMFS(vp); 362 struct proc *p; 363 struct buf *bp; 364 void *base; 365 int sleepreturn = 0; 366 ksiginfoq_t kq; 367 368 base = mfsp->mfs_baseoff; 369 while (mfsp->mfs_shutdown != 1) { 370 while ((bp = BUFQ_GET(mfsp->mfs_buflist)) != NULL) { 371 mfs_doio(bp, base); 372 wakeup((void *)bp); 373 } 374 /* 375 * If a non-ignored signal is received, try to unmount. 376 * If that fails, or the filesystem is already in the 377 * process of being unmounted, clear the signal (it has been 378 * "processed"), otherwise we will loop here, as tsleep 379 * will always return EINTR/ERESTART. 380 */ 381 if (sleepreturn != 0) { 382 /* 383 * XXX Freeze syncer. Must do this before locking 384 * the mount point. See dounmount() for details. 385 */ 386 mutex_enter(&syncer_mutex); 387 if (vfs_busy(mp, LK_NOWAIT, 0) != 0) 388 mutex_exit(&syncer_mutex); 389 else if (dounmount(mp, 0, l) != 0) { 390 p = l->l_proc; 391 ksiginfo_queue_init(&kq); 392 mutex_enter(&p->p_smutex); 393 sigclearall(p, NULL, &kq); 394 mutex_exit(&p->p_smutex); 395 ksiginfo_queue_drain(&kq); 396 } 397 sleepreturn = 0; 398 continue; 399 } 400 401 sleepreturn = tsleep(vp, mfs_pri, "mfsidl", 0); 402 } 403 KASSERT(BUFQ_PEEK(mfsp->mfs_buflist) == NULL); 404 bufq_free(mfsp->mfs_buflist); 405 return (sleepreturn); 406 } 407 408 /* 409 * Get file system statistics. 410 */ 411 int 412 mfs_statvfs(struct mount *mp, struct statvfs *sbp) 413 { 414 int error; 415 416 error = ffs_statvfs(mp, sbp); 417 if (error) 418 return error; 419 (void)strncpy(sbp->f_fstypename, mp->mnt_op->vfs_name, 420 sizeof(sbp->f_fstypename)); 421 sbp->f_fstypename[sizeof(sbp->f_fstypename) - 1] = '\0'; 422 return 0; 423 } 424
Indexes created Mon Sep 29 13:09:55 GMT 2025