1 /* $NetBSD: mfs_vnops.c,v 1.56 2015/01/14 11:21:31 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 1.56 2015/01/14 11:21:31 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_fallocate_desc, genfs_eopnotsupp }, /* fallocate */ 72 { &vop_fdiscard_desc, genfs_eopnotsupp }, /* fdiscard */ 73 { &vop_ioctl_desc, mfs_ioctl }, /* ioctl */ 74 { &vop_poll_desc, mfs_poll }, /* poll */ 75 { &vop_revoke_desc, mfs_revoke }, /* revoke */ 76 { &vop_mmap_desc, mfs_mmap }, /* mmap */ 77 { &vop_fsync_desc, spec_fsync }, /* fsync */ 78 { &vop_seek_desc, mfs_seek }, /* seek */ 79 { &vop_remove_desc, mfs_remove }, /* remove */ 80 { &vop_link_desc, mfs_link }, /* link */ 81 { &vop_rename_desc, mfs_rename }, /* rename */ 82 { &vop_mkdir_desc, mfs_mkdir }, /* mkdir */ 83 { &vop_rmdir_desc, mfs_rmdir }, /* rmdir */ 84 { &vop_symlink_desc, mfs_symlink }, /* symlink */ 85 { &vop_readdir_desc, mfs_readdir }, /* readdir */ 86 { &vop_readlink_desc, mfs_readlink }, /* readlink */ 87 { &vop_abortop_desc, mfs_abortop }, /* abortop */ 88 { &vop_inactive_desc, mfs_inactive }, /* inactive */ 89 { &vop_reclaim_desc, mfs_reclaim }, /* reclaim */ 90 { &vop_lock_desc, genfs_nolock }, /* lock */ 91 { &vop_unlock_desc, genfs_nounlock }, /* unlock */ 92 { &vop_bmap_desc, mfs_bmap }, /* bmap */ 93 { &vop_strategy_desc, mfs_strategy }, /* strategy */ 94 { &vop_print_desc, mfs_print }, /* print */ 95 { &vop_islocked_desc, mfs_islocked }, /* islocked */ 96 { &vop_pathconf_desc, mfs_pathconf }, /* pathconf */ 97 { &vop_advlock_desc, mfs_advlock }, /* advlock */ 98 { &vop_bwrite_desc, mfs_bwrite }, /* bwrite */ 99 { &vop_putpages_desc, mfs_putpages }, /* putpages */ 100 { NULL, NULL } 101 }; 102 const struct vnodeopv_desc mfs_vnodeop_opv_desc = 103 { &mfs_vnodeop_p, mfs_vnodeop_entries }; 104 105 /* 106 * Vnode Operations. 107 * 108 * Open called to allow memory filesystem to initialize and 109 * validate before actual IO. Record our process identifier 110 * so we can tell when we are doing I/O to ourself. 111 */ 112 /* ARGSUSED */ 113 int 114 mfs_open(void *v) 115 { 116 struct vop_open_args /* { 117 struct vnode *a_vp; 118 int a_mode; 119 kauth_cred_t a_cred; 120 } */ *ap = v; 121 122 if (ap->a_vp->v_type != VBLK) { 123 panic("mfs_ioctl not VBLK"); 124 /* NOTREACHED */ 125 } 126 return (0); 127 } 128 129 /* 130 * Pass I/O requests to the memory filesystem process. 131 */ 132 int 133 mfs_strategy(void *v) 134 { 135 struct vop_strategy_args /* { 136 struct vnode *a_vp; 137 struct buf *a_bp; 138 } */ *ap = v; 139 struct vnode *vp = ap->a_vp; 140 struct buf *bp = ap->a_bp; 141 struct mfsnode *mfsp; 142 143 if (vp->v_type != VBLK || vp->v_usecount == 0) 144 panic("mfs_strategy: bad dev"); 145 mfsp = VTOMFS(vp); 146 /* check for mini-root access */ 147 if (mfsp->mfs_proc == NULL) { 148 void *base; 149 150 base = (char *)mfsp->mfs_baseoff + (bp->b_blkno << DEV_BSHIFT); 151 if (bp->b_flags & B_READ) 152 memcpy(bp->b_data, base, bp->b_bcount); 153 else 154 memcpy(base, bp->b_data, bp->b_bcount); 155 bp->b_resid = 0; 156 biodone(bp); 157 } else if (mfsp->mfs_proc == curproc) { 158 mfs_doio(bp, mfsp->mfs_baseoff); 159 } else if (doing_shutdown) { 160 /* 161 * bitbucket I/O during shutdown. 162 * Note that reads should *not* happen here, but.. 163 */ 164 if (bp->b_flags & B_READ) 165 printf("warning: mfs read during shutdown\n"); 166 bp->b_resid = 0; 167 biodone(bp); 168 } else { 169 mutex_enter(&mfs_lock); 170 bufq_put(mfsp->mfs_buflist, bp); 171 cv_broadcast(&mfsp->mfs_cv); 172 mutex_exit(&mfs_lock); 173 } 174 return (0); 175 } 176 177 /* 178 * Memory file system I/O. 179 */ 180 void 181 mfs_doio(struct buf *bp, void *base) 182 { 183 184 base = (char *)base + (bp->b_blkno << DEV_BSHIFT); 185 if (bp->b_flags & B_READ) 186 bp->b_error = copyin(base, bp->b_data, bp->b_bcount); 187 else 188 bp->b_error = copyout(bp->b_data, base, bp->b_bcount); 189 if (bp->b_error == 0) 190 bp->b_resid = 0; 191 biodone(bp); 192 } 193 194 /* 195 * This is a noop, simply returning what one has been given. 196 */ 197 int 198 mfs_bmap(void *v) 199 { 200 struct vop_bmap_args /* { 201 struct vnode *a_vp; 202 daddr_t a_bn; 203 struct vnode **a_vpp; 204 daddr_t *a_bnp; 205 int *a_runp; 206 } */ *ap = v; 207 208 if (ap->a_vpp != NULL) 209 *ap->a_vpp = ap->a_vp; 210 if (ap->a_bnp != NULL) 211 *ap->a_bnp = ap->a_bn; 212 if (ap->a_runp != NULL) 213 *ap->a_runp = 0; 214 return (0); 215 } 216 217 /* 218 * Memory filesystem close routine 219 */ 220 /* ARGSUSED */ 221 int 222 mfs_close(void *v) 223 { 224 struct vop_close_args /* { 225 struct vnode *a_vp; 226 int a_fflag; 227 kauth_cred_t a_cred; 228 } */ *ap = v; 229 struct vnode *vp = ap->a_vp; 230 struct mfsnode *mfsp = VTOMFS(vp); 231 struct buf *bp; 232 int error; 233 234 /* 235 * Finish any pending I/O requests. 236 */ 237 mutex_enter(&mfs_lock); 238 while ((bp = bufq_get(mfsp->mfs_buflist)) != NULL) { 239 mutex_exit(&mfs_lock); 240 mfs_doio(bp, mfsp->mfs_baseoff); 241 mutex_enter(&mfs_lock); 242 } 243 mutex_exit(&mfs_lock); 244 /* 245 * On last close of a memory filesystem 246 * we must invalidate any in core blocks, so that 247 * we can, free up its vnode. 248 */ 249 if ((error = vinvalbuf(vp, V_SAVE, ap->a_cred, curlwp, 0, 0)) != 0) 250 return (error); 251 /* 252 * There should be no way to have any more uses of this 253 * vnode, so if we find any other uses, it is a panic. 254 */ 255 if (bufq_peek(mfsp->mfs_buflist) != NULL) 256 panic("mfs_close"); 257 /* 258 * Send a request to the filesystem server to exit. 259 */ 260 mutex_enter(&mfs_lock); 261 mfsp->mfs_shutdown = 1; 262 cv_broadcast(&mfsp->mfs_cv); 263 mutex_exit(&mfs_lock); 264 return (0); 265 } 266 267 /* 268 * Memory filesystem inactive routine 269 */ 270 /* ARGSUSED */ 271 int 272 mfs_inactive(void *v) 273 { 274 struct vop_inactive_args /* { 275 struct vnode *a_vp; 276 } */ *ap = v; 277 struct vnode *vp = ap->a_vp; 278 struct mfsnode *mfsp = VTOMFS(vp); 279 280 if (bufq_peek(mfsp->mfs_buflist) != NULL) 281 panic("mfs_inactive: not inactive (mfs_buflist %p)", 282 bufq_peek(mfsp->mfs_buflist)); 283 284 return VOCALL(spec_vnodeop_p, VOFFSET(vop_inactive), ap); 285 } 286 287 /* 288 * Reclaim a memory filesystem devvp so that it can be reused. 289 */ 290 int 291 mfs_reclaim(void *v) 292 { 293 struct vop_reclaim_args /* { 294 struct vnode *a_vp; 295 } */ *ap = v; 296 struct vnode *vp = ap->a_vp; 297 struct mfsnode *mfsp = VTOMFS(vp); 298 int refcnt; 299 300 mutex_enter(&mfs_lock); 301 vp->v_data = NULL; 302 refcnt = --mfsp->mfs_refcnt; 303 mutex_exit(&mfs_lock); 304 305 if (refcnt == 0) { 306 bufq_free(mfsp->mfs_buflist); 307 cv_destroy(&mfsp->mfs_cv); 308 kmem_free(mfsp, sizeof(*mfsp)); 309 } 310 311 return VOCALL(spec_vnodeop_p, VOFFSET(vop_reclaim), ap); 312 } 313 314 /* 315 * Print out the contents of an mfsnode. 316 */ 317 int 318 mfs_print(void *v) 319 { 320 struct vop_print_args /* { 321 struct vnode *a_vp; 322 } */ *ap = v; 323 struct mfsnode *mfsp = VTOMFS(ap->a_vp); 324 325 printf("tag VT_MFS, pid %d, base %p, size %ld\n", 326 (mfsp->mfs_proc != NULL) ? mfsp->mfs_proc->p_pid : 0, 327 mfsp->mfs_baseoff, mfsp->mfs_size); 328 return (0); 329 } 330