mfs_vfsops.c revision 1.51.2.6
1 /* $NetBSD: mfs_vfsops.c,v 1.51.2.6 2004/11/02 07:53:37 skrll 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 1.51.2.6 2004/11/02 07:53:37 skrll 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/syncfs/syncfs.h> 55 56 #include <ufs/ufs/quota.h> 57 #include <ufs/ufs/inode.h> 58 #include <ufs/ufs/ufsmount.h> 59 #include <ufs/ufs/ufs_extern.h> 60 61 #include <ufs/ffs/fs.h> 62 #include <ufs/ffs/ffs_extern.h> 63 64 #include <ufs/mfs/mfsnode.h> 65 #include <ufs/mfs/mfs_extern.h> 66 67 caddr_t mfs_rootbase; /* address of mini-root in kernel virtual memory */ 68 u_long mfs_rootsize; /* size of mini-root in bytes */ 69 70 static int mfs_minor; /* used for building internal dev_t */ 71 72 extern int (**mfs_vnodeop_p) __P((void *)); 73 74 MALLOC_DEFINE(M_MFSNODE, "MFS node", "MFS vnode private part"); 75 76 /* 77 * mfs vfs operations. 78 */ 79 80 extern const struct vnodeopv_desc mfs_vnodeop_opv_desc; 81 82 const struct vnodeopv_desc * const mfs_vnodeopv_descs[] = { 83 &mfs_vnodeop_opv_desc, 84 NULL, 85 }; 86 87 struct vfsops mfs_vfsops = { 88 MOUNT_MFS, 89 mfs_mount, 90 mfs_start, 91 ffs_unmount, 92 ufs_root, 93 ufs_quotactl, 94 mfs_statvfs, 95 ffs_sync, 96 ffs_vget, 97 ffs_fhtovp, 98 ffs_vptofh, 99 mfs_init, 100 mfs_reinit, 101 mfs_done, 102 NULL, 103 NULL, 104 ufs_check_export, 105 (int (*)(struct mount *, struct vnode *, struct timespec *)) eopnotsupp, 106 mfs_vnodeopv_descs, 107 }; 108 109 SYSCTL_SETUP(sysctl_vfs_mfs_setup, "sysctl vfs.mfs subtree setup") 110 { 111 112 sysctl_createv(clog, 0, NULL, NULL, 113 CTLFLAG_PERMANENT, 114 CTLTYPE_NODE, "vfs", NULL, 115 NULL, 0, NULL, 0, 116 CTL_VFS, CTL_EOL); 117 sysctl_createv(clog, 0, NULL, NULL, 118 CTLFLAG_PERMANENT|CTLFLAG_ALIAS, 119 CTLTYPE_NODE, "mfs", 120 SYSCTL_DESCR("Memory based file system"), 121 NULL, 1, NULL, 0, 122 CTL_VFS, 3, CTL_EOL); 123 /* 124 * XXX the "1" and the "3" above could be dynamic, thereby 125 * eliminating one more instance of the "number to vfs" 126 * mapping problem, but they are in order as taken from 127 * sys/mount.h 128 */ 129 } 130 131 /* 132 * Memory based filesystem initialization. 133 */ 134 void 135 mfs_init() 136 { 137 #ifdef _LKM 138 malloc_type_attach(M_MFSNODE); 139 #endif 140 /* 141 * ffs_init() ensures to initialize necessary resources 142 * only once. 143 */ 144 ffs_init(); 145 } 146 147 void 148 mfs_reinit() 149 { 150 ffs_reinit(); 151 } 152 153 void 154 mfs_done() 155 { 156 /* 157 * ffs_done() ensures to free necessary resources 158 * only once, when it's no more needed. 159 */ 160 ffs_done(); 161 #ifdef _LKM 162 malloc_type_detach(M_MFSNODE); 163 #endif 164 } 165 166 /* 167 * Called by main() when mfs is going to be mounted as root. 168 */ 169 170 int 171 mfs_mountroot() 172 { 173 struct fs *fs; 174 struct mount *mp; 175 struct lwp *l = curlwp; /* XXX */ 176 struct ufsmount *ump; 177 struct mfsnode *mfsp; 178 int error = 0; 179 180 /* 181 * Get vnodes for rootdev. 182 */ 183 if (bdevvp(rootdev, &rootvp)) { 184 printf("mfs_mountroot: can't setup bdevvp's"); 185 return (error); 186 } 187 188 if ((error = vfs_rootmountalloc(MOUNT_MFS, "mfs_root", &mp))) { 189 vrele(rootvp); 190 return (error); 191 } 192 193 mfsp = malloc(sizeof *mfsp, M_MFSNODE, M_WAITOK); 194 rootvp->v_data = mfsp; 195 rootvp->v_op = mfs_vnodeop_p; 196 rootvp->v_tag = VT_MFS; 197 mfsp->mfs_baseoff = mfs_rootbase; 198 mfsp->mfs_size = mfs_rootsize; 199 mfsp->mfs_vnode = rootvp; 200 mfsp->mfs_proc = NULL; /* indicate kernel space */ 201 mfsp->mfs_shutdown = 0; 202 bufq_alloc(&mfsp->mfs_buflist, BUFQ_FCFS); 203 if ((error = ffs_mountfs(rootvp, mp, l)) != 0) { 204 mp->mnt_op->vfs_refcount--; 205 vfs_unbusy(mp); 206 bufq_free(&mfsp->mfs_buflist); 207 free(mp, M_MOUNT); 208 free(mfsp, M_MFSNODE); 209 vrele(rootvp); 210 return (error); 211 } 212 simple_lock(&mountlist_slock); 213 CIRCLEQ_INSERT_TAIL(&mountlist, mp, mnt_list); 214 simple_unlock(&mountlist_slock); 215 mp->mnt_vnodecovered = NULLVP; 216 ump = VFSTOUFS(mp); 217 fs = ump->um_fs; 218 (void) copystr(mp->mnt_stat.f_mntonname, fs->fs_fsmnt, MNAMELEN - 1, 0); 219 (void)ffs_statvfs(mp, &mp->mnt_stat, l); 220 vfs_unbusy(mp); 221 return (0); 222 } 223 224 /* 225 * This is called early in boot to set the base address and size 226 * of the mini-root. 227 */ 228 int 229 mfs_initminiroot(base) 230 caddr_t base; 231 { 232 struct fs *fs = (struct fs *)(base + SBLOCK_UFS1); 233 234 /* check for valid super block */ 235 if (fs->fs_magic != FS_UFS1_MAGIC || fs->fs_bsize > MAXBSIZE || 236 fs->fs_bsize < sizeof(struct fs)) 237 return (0); 238 mountroot = mfs_mountroot; 239 mfs_rootbase = base; 240 mfs_rootsize = fs->fs_fsize * fs->fs_size; 241 rootdev = makedev(255, mfs_minor); 242 mfs_minor++; 243 return (mfs_rootsize); 244 } 245 246 /* 247 * VFS Operations. 248 * 249 * mount system call 250 */ 251 /* ARGSUSED */ 252 int 253 mfs_mount(mp, path, data, ndp, l) 254 struct mount *mp; 255 const char *path; 256 void *data; 257 struct nameidata *ndp; 258 struct lwp *l; 259 { 260 struct vnode *devvp; 261 struct mfs_args args; 262 struct ufsmount *ump; 263 struct fs *fs; 264 struct mfsnode *mfsp; 265 struct proc *p; 266 int flags, error; 267 268 p = l->l_proc; 269 if (mp->mnt_flag & MNT_GETARGS) { 270 struct vnode *vp; 271 struct mfsnode *mfsp; 272 273 ump = VFSTOUFS(mp); 274 if (ump == NULL) 275 return EIO; 276 277 vp = ump->um_devvp; 278 if (vp == NULL) 279 return EIO; 280 281 mfsp = VTOMFS(vp); 282 if (mfsp == NULL) 283 return EIO; 284 285 args.fspec = NULL; 286 vfs_showexport(mp, &args.export, &ump->um_export); 287 args.base = mfsp->mfs_baseoff; 288 args.size = mfsp->mfs_size; 289 return copyout(&args, data, sizeof(args)); 290 } 291 /* 292 * XXX turn off async to avoid hangs when writing lots of data. 293 * the problem is that MFS needs to allocate pages to clean pages, 294 * so if we wait until the last minute to clean pages then there 295 * may not be any pages available to do the cleaning. 296 * ... and since the default partially-synchronous mode turns out 297 * to not be sufficient under heavy load, make it full synchronous. 298 */ 299 mp->mnt_flag &= ~MNT_ASYNC; 300 mp->mnt_flag |= MNT_SYNCHRONOUS; 301 302 error = copyin(data, (caddr_t)&args, sizeof (struct mfs_args)); 303 if (error) 304 return (error); 305 306 /* 307 * If updating, check whether changing from read-only to 308 * read/write; if there is no device name, that's all we do. 309 */ 310 if (mp->mnt_flag & MNT_UPDATE) { 311 ump = VFSTOUFS(mp); 312 fs = ump->um_fs; 313 if (fs->fs_ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) { 314 flags = WRITECLOSE; 315 if (mp->mnt_flag & MNT_FORCE) 316 flags |= FORCECLOSE; 317 error = ffs_flushfiles(mp, flags, l); 318 if (error) 319 return (error); 320 } 321 if (fs->fs_ronly && (mp->mnt_iflag & IMNT_WANTRDWR)) 322 fs->fs_ronly = 0; 323 if (args.fspec == 0) 324 return (vfs_export(mp, &ump->um_export, &args.export)); 325 return (0); 326 } 327 error = getnewvnode(VT_MFS, (struct mount *)0, mfs_vnodeop_p, &devvp); 328 if (error) 329 return (error); 330 devvp->v_type = VBLK; 331 if (checkalias(devvp, makedev(255, mfs_minor), (struct mount *)0)) 332 panic("mfs_mount: dup dev"); 333 mfs_minor++; 334 mfsp = (struct mfsnode *)malloc(sizeof *mfsp, M_MFSNODE, M_WAITOK); 335 devvp->v_data = mfsp; 336 mfsp->mfs_baseoff = args.base; 337 mfsp->mfs_size = args.size; 338 mfsp->mfs_vnode = devvp; 339 mfsp->mfs_proc = p; 340 mfsp->mfs_shutdown = 0; 341 bufq_alloc(&mfsp->mfs_buflist, BUFQ_FCFS); 342 if ((error = ffs_mountfs(devvp, mp, l)) != 0) { 343 mfsp->mfs_shutdown = 1; 344 vrele(devvp); 345 return (error); 346 } 347 ump = VFSTOUFS(mp); 348 fs = ump->um_fs; 349 error = set_statvfs_info(path, UIO_USERSPACE, args.fspec, 350 UIO_USERSPACE, mp, l); 351 if (error) 352 return error; 353 (void)strncpy(fs->fs_fsmnt, mp->mnt_stat.f_mntonname, 354 sizeof(fs->fs_fsmnt)); 355 fs->fs_fsmnt[sizeof(fs->fs_fsmnt) - 1] = '\0'; 356 /* XXX: cleanup on error */ 357 return 0; 358 } 359 360 int mfs_pri = PWAIT | PCATCH; /* XXX prob. temp */ 361 362 /* 363 * Used to grab the process and keep it in the kernel to service 364 * memory filesystem I/O requests. 365 * 366 * Loop servicing I/O requests. 367 * Copy the requested data into or out of the memory filesystem 368 * address space. 369 */ 370 /* ARGSUSED */ 371 int 372 mfs_start(mp, flags, l) 373 struct mount *mp; 374 int flags; 375 struct lwp *l; 376 { 377 struct vnode *vp = VFSTOUFS(mp)->um_devvp; 378 struct mfsnode *mfsp = VTOMFS(vp); 379 struct buf *bp; 380 caddr_t base; 381 int sleepreturn = 0; 382 383 base = mfsp->mfs_baseoff; 384 while (mfsp->mfs_shutdown != 1) { 385 while ((bp = BUFQ_GET(&mfsp->mfs_buflist)) != NULL) { 386 mfs_doio(bp, base); 387 wakeup((caddr_t)bp); 388 } 389 /* 390 * If a non-ignored signal is received, try to unmount. 391 * If that fails, or the filesystem is already in the 392 * process of being unmounted, clear the signal (it has been 393 * "processed"), otherwise we will loop here, as tsleep 394 * will always return EINTR/ERESTART. 395 */ 396 if (sleepreturn != 0) { 397 /* 398 * XXX Freeze syncer. Must do this before locking 399 * the mount point. See dounmount() for details. 400 */ 401 lockmgr(&syncer_lock, LK_EXCLUSIVE, NULL); 402 if (vfs_busy(mp, LK_NOWAIT, 0) != 0) 403 lockmgr(&syncer_lock, LK_RELEASE, NULL); 404 else if (dounmount(mp, 0, l) != 0) 405 CLRSIG(l->l_proc, CURSIG(l)); 406 sleepreturn = 0; 407 continue; 408 } 409 410 sleepreturn = tsleep(vp, mfs_pri, "mfsidl", 0); 411 } 412 KASSERT(BUFQ_PEEK(&mfsp->mfs_buflist) == NULL); 413 bufq_free(&mfsp->mfs_buflist); 414 return (sleepreturn); 415 } 416 417 /* 418 * Get file system statistics. 419 */ 420 int 421 mfs_statvfs(mp, sbp, l) 422 struct mount *mp; 423 struct statvfs *sbp; 424 struct lwp *l; 425 { 426 int error; 427 428 error = ffs_statvfs(mp, sbp, l); 429 if (error) 430 return error; 431 (void)strncpy(sbp->f_fstypename, mp->mnt_op->vfs_name, 432 sizeof(sbp->f_fstypename)); 433 sbp->f_fstypename[sizeof(sbp->f_fstypename) - 1] = '\0'; 434 return 0; 435 } 436
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