mfs_vfsops.c revision 1.56
1/* $NetBSD: mfs_vfsops.c,v 1.56 2004/04/21 01:05:46 christos 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 1.56 2004/04/21 01:05:46 christos 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/mount.h> 49#include <sys/signalvar.h> 50#include <sys/vnode.h> 51#include <sys/malloc.h> 52 53#include <miscfs/syncfs/syncfs.h> 54 55#include <ufs/ufs/quota.h> 56#include <ufs/ufs/inode.h> 57#include <ufs/ufs/ufsmount.h> 58#include <ufs/ufs/ufs_extern.h> 59 60#include <ufs/ffs/fs.h> 61#include <ufs/ffs/ffs_extern.h> 62 63#include <ufs/mfs/mfsnode.h> 64#include <ufs/mfs/mfs_extern.h> 65 66caddr_t mfs_rootbase; /* address of mini-root in kernel virtual memory */ 67u_long mfs_rootsize; /* size of mini-root in bytes */ 68 69static int mfs_minor; /* used for building internal dev_t */ 70 71extern int (**mfs_vnodeop_p) __P((void *)); 72 73MALLOC_DEFINE(M_MFSNODE, "MFS node", "MFS vnode private part"); 74 75/* 76 * mfs vfs operations. 77 */ 78 79extern const struct vnodeopv_desc mfs_vnodeop_opv_desc; 80 81const struct vnodeopv_desc * const mfs_vnodeopv_descs[] = { 82 &mfs_vnodeop_opv_desc, 83 NULL, 84}; 85 86struct vfsops mfs_vfsops = { 87 MOUNT_MFS, 88 mfs_mount, 89 mfs_start, 90 ffs_unmount, 91 ufs_root, 92 ufs_quotactl, 93 mfs_statvfs, 94 ffs_sync, 95 ffs_vget, 96 ffs_fhtovp, 97 ffs_vptofh, 98 mfs_init, 99 mfs_reinit, 100 mfs_done, 101 NULL, 102 NULL, 103 ufs_check_export, 104 mfs_vnodeopv_descs, 105}; 106 107SYSCTL_SETUP(sysctl_vfs_mfs_setup, "sysctl vfs.mfs subtree setup") 108{ 109 110 sysctl_createv(clog, 0, NULL, NULL, 111 CTLFLAG_PERMANENT, 112 CTLTYPE_NODE, "vfs", NULL, 113 NULL, 0, NULL, 0, 114 CTL_VFS, CTL_EOL); 115 sysctl_createv(clog, 0, NULL, NULL, 116 CTLFLAG_PERMANENT|CTLFLAG_ALIAS, 117 CTLTYPE_NODE, "mfs", NULL, 118 NULL, 1, NULL, 0, 119 CTL_VFS, 3, CTL_EOL); 120 /* 121 * XXX the "1" and the "3" above could be dynamic, thereby 122 * eliminating one more instance of the "number to vfs" 123 * mapping problem, but they are in order as taken from 124 * sys/mount.h 125 */ 126} 127 128/* 129 * Memory based filesystem initialization. 130 */ 131void 132mfs_init() 133{ 134#ifdef _LKM 135 malloc_type_attach(M_MFSNODE); 136#endif 137 /* 138 * ffs_init() ensures to initialize necessary resources 139 * only once. 140 */ 141 ffs_init(); 142} 143 144void 145mfs_reinit() 146{ 147 ffs_reinit(); 148} 149 150void 151mfs_done() 152{ 153 /* 154 * ffs_done() ensures to free necessary resources 155 * only once, when it's no more needed. 156 */ 157 ffs_done(); 158#ifdef _LKM 159 malloc_type_detach(M_MFSNODE); 160#endif 161} 162 163/* 164 * Called by main() when mfs is going to be mounted as root. 165 */ 166 167int 168mfs_mountroot() 169{ 170 struct fs *fs; 171 struct mount *mp; 172 struct proc *p = curproc; /* XXX */ 173 struct ufsmount *ump; 174 struct mfsnode *mfsp; 175 int error = 0; 176 177 /* 178 * Get vnodes for rootdev. 179 */ 180 if (bdevvp(rootdev, &rootvp)) { 181 printf("mfs_mountroot: can't setup bdevvp's"); 182 return (error); 183 } 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, BUFQ_FCFS); 200 if ((error = ffs_mountfs(rootvp, mp, p)) != 0) { 201 mp->mnt_op->vfs_refcount--; 202 vfs_unbusy(mp); 203 bufq_free(&mfsp->mfs_buflist); 204 free(mp, M_MOUNT); 205 free(mfsp, M_MFSNODE); 206 vrele(rootvp); 207 return (error); 208 } 209 simple_lock(&mountlist_slock); 210 CIRCLEQ_INSERT_TAIL(&mountlist, mp, mnt_list); 211 simple_unlock(&mountlist_slock); 212 mp->mnt_vnodecovered = NULLVP; 213 ump = VFSTOUFS(mp); 214 fs = ump->um_fs; 215 (void) copystr(mp->mnt_stat.f_mntonname, fs->fs_fsmnt, MNAMELEN - 1, 0); 216 (void)ffs_statvfs(mp, &mp->mnt_stat, p); 217 vfs_unbusy(mp); 218 inittodr((time_t)0); 219 return (0); 220} 221 222/* 223 * This is called early in boot to set the base address and size 224 * of the mini-root. 225 */ 226int 227mfs_initminiroot(base) 228 caddr_t base; 229{ 230 struct fs *fs = (struct fs *)(base + SBLOCK_UFS1); 231 232 /* check for valid super block */ 233 if (fs->fs_magic != FS_UFS1_MAGIC || fs->fs_bsize > MAXBSIZE || 234 fs->fs_bsize < sizeof(struct fs)) 235 return (0); 236 mountroot = mfs_mountroot; 237 mfs_rootbase = base; 238 mfs_rootsize = fs->fs_fsize * fs->fs_size; 239 rootdev = makedev(255, mfs_minor); 240 mfs_minor++; 241 return (mfs_rootsize); 242} 243 244/* 245 * VFS Operations. 246 * 247 * mount system call 248 */ 249/* ARGSUSED */ 250int 251mfs_mount(mp, path, data, ndp, p) 252 struct mount *mp; 253 const char *path; 254 void *data; 255 struct nameidata *ndp; 256 struct proc *p; 257{ 258 struct vnode *devvp; 259 struct mfs_args args; 260 struct ufsmount *ump; 261 struct fs *fs; 262 struct mfsnode *mfsp; 263 int flags, error; 264 265 if (mp->mnt_flag & MNT_GETARGS) { 266 struct vnode *vp; 267 struct mfsnode *mfsp; 268 269 ump = VFSTOUFS(mp); 270 if (ump == NULL) 271 return EIO; 272 273 vp = ump->um_devvp; 274 if (vp == NULL) 275 return EIO; 276 277 mfsp = VTOMFS(vp); 278 if (mfsp == NULL) 279 return EIO; 280 281 args.fspec = NULL; 282 vfs_showexport(mp, &args.export, &ump->um_export); 283 args.base = mfsp->mfs_baseoff; 284 args.size = mfsp->mfs_size; 285 return copyout(&args, data, sizeof(args)); 286 } 287 /* 288 * XXX turn off async to avoid hangs when writing lots of data. 289 * the problem is that MFS needs to allocate pages to clean pages, 290 * so if we wait until the last minute to clean pages then there 291 * may not be any pages available to do the cleaning. 292 * ... and since the default partially-synchronous mode turns out 293 * to not be sufficient under heavy load, make it full synchronous. 294 */ 295 mp->mnt_flag &= ~MNT_ASYNC; 296 mp->mnt_flag |= MNT_SYNCHRONOUS; 297 298 error = copyin(data, (caddr_t)&args, sizeof (struct mfs_args)); 299 if (error) 300 return (error); 301 302 /* 303 * If updating, check whether changing from read-only to 304 * read/write; if there is no device name, that's all we do. 305 */ 306 if (mp->mnt_flag & MNT_UPDATE) { 307 ump = VFSTOUFS(mp); 308 fs = ump->um_fs; 309 if (fs->fs_ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) { 310 flags = WRITECLOSE; 311 if (mp->mnt_flag & MNT_FORCE) 312 flags |= FORCECLOSE; 313 error = ffs_flushfiles(mp, flags, p); 314 if (error) 315 return (error); 316 } 317 if (fs->fs_ronly && (mp->mnt_iflag & IMNT_WANTRDWR)) 318 fs->fs_ronly = 0; 319 if (args.fspec == 0) 320 return (vfs_export(mp, &ump->um_export, &args.export)); 321 return (0); 322 } 323 error = getnewvnode(VT_MFS, (struct mount *)0, mfs_vnodeop_p, &devvp); 324 if (error) 325 return (error); 326 devvp->v_type = VBLK; 327 if (checkalias(devvp, makedev(255, mfs_minor), (struct mount *)0)) 328 panic("mfs_mount: dup dev"); 329 mfs_minor++; 330 mfsp = (struct mfsnode *)malloc(sizeof *mfsp, M_MFSNODE, M_WAITOK); 331 devvp->v_data = mfsp; 332 mfsp->mfs_baseoff = args.base; 333 mfsp->mfs_size = args.size; 334 mfsp->mfs_vnode = devvp; 335 mfsp->mfs_proc = p; 336 mfsp->mfs_shutdown = 0; 337 bufq_alloc(&mfsp->mfs_buflist, BUFQ_FCFS); 338 if ((error = ffs_mountfs(devvp, mp, p)) != 0) { 339 mfsp->mfs_shutdown = 1; 340 vrele(devvp); 341 return (error); 342 } 343 ump = VFSTOUFS(mp); 344 fs = ump->um_fs; 345 error = set_statvfs_info(path, UIO_USERSPACE, args.fspec, 346 UIO_USERSPACE, mp, p); 347 (void)memcpy(fs->fs_fsmnt, mp->mnt_stat.f_mntonname, 348 sizeof(mp->mnt_stat.f_mntonname)); 349 return error; 350} 351 352int mfs_pri = PWAIT | PCATCH; /* XXX prob. temp */ 353 354/* 355 * Used to grab the process and keep it in the kernel to service 356 * memory filesystem I/O requests. 357 * 358 * Loop servicing I/O requests. 359 * Copy the requested data into or out of the memory filesystem 360 * address space. 361 */ 362/* ARGSUSED */ 363int 364mfs_start(mp, flags, p) 365 struct mount *mp; 366 int flags; 367 struct proc *p; 368{ 369 struct vnode *vp = VFSTOUFS(mp)->um_devvp; 370 struct mfsnode *mfsp = VTOMFS(vp); 371 struct buf *bp; 372 caddr_t base; 373 int sleepreturn = 0; 374 struct lwp *l; /* XXX NJWLWP */ 375 376 /* XXX NJWLWP the vnode interface again gives us a proc in a 377 * place where we want a execution context. Cheat. 378 */ 379 KASSERT(curproc == p); 380 l = curlwp; 381 base = mfsp->mfs_baseoff; 382 while (mfsp->mfs_shutdown != 1) { 383 while ((bp = BUFQ_GET(&mfsp->mfs_buflist)) != NULL) { 384 mfs_doio(bp, base); 385 wakeup((caddr_t)bp); 386 } 387 /* 388 * If a non-ignored signal is received, try to unmount. 389 * If that fails, or the filesystem is already in the 390 * process of being unmounted, clear the signal (it has been 391 * "processed"), otherwise we will loop here, as tsleep 392 * will always return EINTR/ERESTART. 393 */ 394 if (sleepreturn != 0) { 395 /* 396 * XXX Freeze syncer. Must do this before locking 397 * the mount point. See dounmount() for details. 398 */ 399 lockmgr(&syncer_lock, LK_EXCLUSIVE, NULL); 400 if (vfs_busy(mp, LK_NOWAIT, 0) != 0) 401 lockmgr(&syncer_lock, LK_RELEASE, NULL); 402 else if (dounmount(mp, 0, p) != 0) 403 CLRSIG(p, CURSIG(l)); 404 sleepreturn = 0; 405 continue; 406 } 407 408 sleepreturn = tsleep(vp, mfs_pri, "mfsidl", 0); 409 } 410 KASSERT(BUFQ_PEEK(&mfsp->mfs_buflist) == NULL); 411 bufq_free(&mfsp->mfs_buflist); 412 return (sleepreturn); 413} 414 415/* 416 * Get file system statistics. 417 */ 418int 419mfs_statvfs(mp, sbp, p) 420 struct mount *mp; 421 struct statvfs *sbp; 422 struct proc *p; 423{ 424 int error; 425 426 error = ffs_statvfs(mp, sbp, p); 427 strncpy(&sbp->f_fstypename[0], mp->mnt_op->vfs_name, MFSNAMELEN); 428 return (error); 429} 430