1 /* $NetBSD: mfs_vnops.c,v 1.54 2010/06/24 13:03:19 hannken Exp $ */ 2 3 /* 4 * Copyright (c) 1989, 1993 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_vnops.c 8.11 (Berkeley) 5/22/95 32 */ 33 34 #include <sys/cdefs.h> 35 __KERNEL_RCSID(0, "$NetBSD: mfs_vnops.c,v 1.54 2010/06/24 13:03:19 hannken Exp $"); 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/time.h> 40 #include <sys/kernel.h> 41 #include <sys/proc.h> 42 #include <sys/buf.h> 43 #include <sys/bufq.h> 44 #include <sys/vnode.h> 45 #include <sys/kmem.h> 46 47 #include <miscfs/genfs/genfs.h> 48 #include <miscfs/specfs/specdev.h> 49 50 #include <machine/vmparam.h> 51 52 #include <ufs/mfs/mfsnode.h> 53 #include <ufs/mfs/mfs_extern.h> 54 55 /* 56 * mfs vnode operations. 57 */ 58 int (**mfs_vnodeop_p)(void *); 59 const struct vnodeopv_entry_desc mfs_vnodeop_entries[] = { 60 { &vop_default_desc, vn_default_error }, 61 { &vop_lookup_desc, mfs_lookup }, /* lookup */ 62 { &vop_create_desc, mfs_create }, /* create */ 63 { &vop_mknod_desc, mfs_mknod }, /* mknod */ 64 { &vop_open_desc, mfs_open }, /* open */ 65 { &vop_close_desc, mfs_close }, /* close */ 66 { &vop_access_desc, mfs_access }, /* access */ 67 { &vop_getattr_desc, mfs_getattr }, /* getattr */ 68 { &vop_setattr_desc, mfs_setattr }, /* setattr */ 69 { &vop_read_desc, mfs_read }, /* read */ 70 { &vop_write_desc, mfs_write }, /* write */ 71 { &vop_ioctl_desc, mfs_ioctl }, /* ioctl */ 72 { &vop_poll_desc, mfs_poll }, /* poll */ 73 { &vop_revoke_desc, mfs_revoke }, /* revoke */ 74 { &vop_mmap_desc, mfs_mmap }, /* mmap */ 75 { &vop_fsync_desc, spec_fsync }, /* fsync */ 76 { &vop_seek_desc, mfs_seek }, /* seek */ 77 { &vop_remove_desc, mfs_remove }, /* remove */ 78 { &vop_link_desc, mfs_link }, /* link */ 79 { &vop_rename_desc, mfs_rename }, /* rename */ 80 { &vop_mkdir_desc, mfs_mkdir }, /* mkdir */ 81 { &vop_rmdir_desc, mfs_rmdir }, /* rmdir */ 82 { &vop_symlink_desc, mfs_symlink }, /* symlink */ 83 { &vop_readdir_desc, mfs_readdir }, /* readdir */ 84 { &vop_readlink_desc, mfs_readlink }, /* readlink */ 85 { &vop_abortop_desc, mfs_abortop }, /* abortop */ 86 { &vop_inactive_desc, mfs_inactive }, /* inactive */ 87 { &vop_reclaim_desc, mfs_reclaim }, /* reclaim */ 88 { &vop_lock_desc, genfs_nolock }, /* lock */ 89 { &vop_unlock_desc, genfs_nounlock }, /* unlock */ 90 { &vop_bmap_desc, mfs_bmap }, /* bmap */ 91 { &vop_strategy_desc, mfs_strategy }, /* strategy */ 92 { &vop_print_desc, mfs_print }, /* print */ 93 { &vop_islocked_desc, mfs_islocked }, /* islocked */ 94 { &vop_pathconf_desc, mfs_pathconf }, /* pathconf */ 95 { &vop_advlock_desc, mfs_advlock }, /* advlock */ 96 { &vop_bwrite_desc, mfs_bwrite }, /* bwrite */ 97 { &vop_putpages_desc, mfs_putpages }, /* putpages */ 98 { NULL, NULL } 99 }; 100 const struct vnodeopv_desc mfs_vnodeop_opv_desc = 101 { &mfs_vnodeop_p, mfs_vnodeop_entries }; 102 103 /* 104 * Vnode Operations. 105 * 106 * Open called to allow memory filesystem to initialize and 107 * validate before actual IO. Record our process identifier 108 * so we can tell when we are doing I/O to ourself. 109 */ 110 /* ARGSUSED */ 111 int 112 mfs_open(void *v) 113 { 114 struct vop_open_args /* { 115 struct vnode *a_vp; 116 int a_mode; 117 kauth_cred_t a_cred; 118 } */ *ap = v; 119 120 if (ap->a_vp->v_type != VBLK) { 121 panic("mfs_ioctl not VBLK"); 122 /* NOTREACHED */ 123 } 124 return (0); 125 } 126 127 /* 128 * Pass I/O requests to the memory filesystem process. 129 */ 130 int 131 mfs_strategy(void *v) 132 { 133 struct vop_strategy_args /* { 134 struct vnode *a_vp; 135 struct buf *a_bp; 136 } */ *ap = v; 137 struct vnode *vp = ap->a_vp; 138 struct buf *bp = ap->a_bp; 139 struct mfsnode *mfsp; 140 141 if (vp->v_type != VBLK || vp->v_usecount == 0) 142 panic("mfs_strategy: bad dev"); 143 mfsp = VTOMFS(vp); 144 /* check for mini-root access */ 145 if (mfsp->mfs_proc == NULL) { 146 void *base; 147 148 base = (char *)mfsp->mfs_baseoff + (bp->b_blkno << DEV_BSHIFT); 149 if (bp->b_flags & B_READ) 150 memcpy(bp->b_data, base, bp->b_bcount); 151 else 152 memcpy(base, bp->b_data, bp->b_bcount); 153 bp->b_resid = 0; 154 biodone(bp); 155 } else if (mfsp->mfs_proc == curproc) { 156 mfs_doio(bp, mfsp->mfs_baseoff); 157 } else if (doing_shutdown) { 158 /* 159 * bitbucket I/O during shutdown. 160 * Note that reads should *not* happen here, but.. 161 */ 162 if (bp->b_flags & B_READ) 163 printf("warning: mfs read during shutdown\n"); 164 bp->b_resid = 0; 165 biodone(bp); 166 } else { 167 mutex_enter(&mfs_lock); 168 bufq_put(mfsp->mfs_buflist, bp); 169 cv_broadcast(&mfsp->mfs_cv); 170 mutex_exit(&mfs_lock); 171 } 172 return (0); 173 } 174 175 /* 176 * Memory file system I/O. 177 */ 178 void 179 mfs_doio(struct buf *bp, void *base) 180 { 181 182 base = (char *)base + (bp->b_blkno << DEV_BSHIFT); 183 if (bp->b_flags & B_READ) 184 bp->b_error = copyin(base, bp->b_data, bp->b_bcount); 185 else 186 bp->b_error = copyout(bp->b_data, base, bp->b_bcount); 187 if (bp->b_error == 0) 188 bp->b_resid = 0; 189 biodone(bp); 190 } 191 192 /* 193 * This is a noop, simply returning what one has been given. 194 */ 195 int 196 mfs_bmap(void *v) 197 { 198 struct vop_bmap_args /* { 199 struct vnode *a_vp; 200 daddr_t a_bn; 201 struct vnode **a_vpp; 202 daddr_t *a_bnp; 203 int *a_runp; 204 } */ *ap = v; 205 206 if (ap->a_vpp != NULL) 207 *ap->a_vpp = ap->a_vp; 208 if (ap->a_bnp != NULL) 209 *ap->a_bnp = ap->a_bn; 210 if (ap->a_runp != NULL) 211 *ap->a_runp = 0; 212 return (0); 213 } 214 215 /* 216 * Memory filesystem close routine 217 */ 218 /* ARGSUSED */ 219 int 220 mfs_close(void *v) 221 { 222 struct vop_close_args /* { 223 struct vnode *a_vp; 224 int a_fflag; 225 kauth_cred_t a_cred; 226 } */ *ap = v; 227 struct vnode *vp = ap->a_vp; 228 struct mfsnode *mfsp = VTOMFS(vp); 229 struct buf *bp; 230 int error; 231 232 /* 233 * Finish any pending I/O requests. 234 */ 235 mutex_enter(&mfs_lock); 236 while ((bp = bufq_get(mfsp->mfs_buflist)) != NULL) { 237 mutex_exit(&mfs_lock); 238 mfs_doio(bp, mfsp->mfs_baseoff); 239 mutex_enter(&mfs_lock); 240 } 241 mutex_exit(&mfs_lock); 242 /* 243 * On last close of a memory filesystem 244 * we must invalidate any in core blocks, so that 245 * we can, free up its vnode. 246 */ 247 if ((error = vinvalbuf(vp, V_SAVE, ap->a_cred, curlwp, 0, 0)) != 0) 248 return (error); 249 /* 250 * There should be no way to have any more uses of this 251 * vnode, so if we find any other uses, it is a panic. 252 */ 253 if (bufq_peek(mfsp->mfs_buflist) != NULL) 254 panic("mfs_close"); 255 /* 256 * Send a request to the filesystem server to exit. 257 */ 258 mutex_enter(&mfs_lock); 259 mfsp->mfs_shutdown = 1; 260 cv_broadcast(&mfsp->mfs_cv); 261 mutex_exit(&mfs_lock); 262 return (0); 263 } 264 265 /* 266 * Memory filesystem inactive routine 267 */ 268 /* ARGSUSED */ 269 int 270 mfs_inactive(void *v) 271 { 272 struct vop_inactive_args /* { 273 struct vnode *a_vp; 274 } */ *ap = v; 275 struct vnode *vp = ap->a_vp; 276 struct mfsnode *mfsp = VTOMFS(vp); 277 278 if (bufq_peek(mfsp->mfs_buflist) != NULL) 279 panic("mfs_inactive: not inactive (mfs_buflist %p)", 280 bufq_peek(mfsp->mfs_buflist)); 281 VOP_UNLOCK(vp); 282 return (0); 283 } 284 285 /* 286 * Reclaim a memory filesystem devvp so that it can be reused. 287 */ 288 int 289 mfs_reclaim(void *v) 290 { 291 struct vop_reclaim_args /* { 292 struct vnode *a_vp; 293 } */ *ap = v; 294 struct vnode *vp = ap->a_vp; 295 struct mfsnode *mfsp = VTOMFS(vp); 296 int refcnt; 297 298 mutex_enter(&mfs_lock); 299 vp->v_data = NULL; 300 refcnt = --mfsp->mfs_refcnt; 301 mutex_exit(&mfs_lock); 302 303 if (refcnt == 0) { 304 bufq_free(mfsp->mfs_buflist); 305 cv_destroy(&mfsp->mfs_cv); 306 kmem_free(mfsp, sizeof(*mfsp)); 307 } 308 309 return (0); 310 } 311 312 /* 313 * Print out the contents of an mfsnode. 314 */ 315 int 316 mfs_print(void *v) 317 { 318 struct vop_print_args /* { 319 struct vnode *a_vp; 320 } */ *ap = v; 321 struct mfsnode *mfsp = VTOMFS(ap->a_vp); 322 323 printf("tag VT_MFS, pid %d, base %p, size %ld\n", 324 (mfsp->mfs_proc != NULL) ? mfsp->mfs_proc->p_pid : 0, 325 mfsp->mfs_baseoff, mfsp->mfs_size); 326 return (0); 327 } 328