1 /* $NetBSD: mfs_vnops.c,v 1.64 2022/03/19 13:48:42 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 1.64 2022/03/19 13:48:42 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_parsepath_desc, genfs_parsepath }, /* parsepath */ 62 { &vop_lookup_desc, genfs_badop }, /* lookup */ 63 { &vop_create_desc, genfs_badop }, /* create */ 64 { &vop_mknod_desc, genfs_badop }, /* mknod */ 65 { &vop_open_desc, mfs_open }, /* open */ 66 { &vop_close_desc, mfs_close }, /* close */ 67 { &vop_access_desc, genfs_badop }, /* access */ 68 { &vop_accessx_desc, genfs_badop }, /* accessx */ 69 { &vop_getattr_desc, genfs_badop }, /* getattr */ 70 { &vop_setattr_desc, genfs_badop }, /* setattr */ 71 { &vop_read_desc, genfs_badop }, /* read */ 72 { &vop_write_desc, genfs_badop }, /* write */ 73 { &vop_fallocate_desc, genfs_eopnotsupp }, /* fallocate */ 74 { &vop_fdiscard_desc, genfs_eopnotsupp }, /* fdiscard */ 75 { &vop_ioctl_desc, genfs_enoioctl }, /* ioctl */ 76 { &vop_poll_desc, genfs_badop }, /* poll */ 77 { &vop_revoke_desc, genfs_revoke }, /* revoke */ 78 { &vop_mmap_desc, genfs_badop }, /* mmap */ 79 { &vop_fsync_desc, spec_fsync }, /* fsync */ 80 { &vop_seek_desc, genfs_badop }, /* seek */ 81 { &vop_remove_desc, genfs_badop }, /* remove */ 82 { &vop_link_desc, genfs_badop }, /* link */ 83 { &vop_rename_desc, genfs_badop }, /* rename */ 84 { &vop_mkdir_desc, genfs_badop }, /* mkdir */ 85 { &vop_rmdir_desc, genfs_badop }, /* rmdir */ 86 { &vop_symlink_desc, genfs_badop }, /* symlink */ 87 { &vop_readdir_desc, genfs_badop }, /* readdir */ 88 { &vop_readlink_desc, genfs_badop }, /* readlink */ 89 { &vop_abortop_desc, genfs_badop }, /* abortop */ 90 { &vop_inactive_desc, mfs_inactive }, /* inactive */ 91 { &vop_reclaim_desc, mfs_reclaim }, /* reclaim */ 92 { &vop_lock_desc, genfs_lock }, /* lock */ 93 { &vop_unlock_desc, genfs_unlock }, /* unlock */ 94 { &vop_bmap_desc, mfs_bmap }, /* bmap */ 95 { &vop_strategy_desc, mfs_strategy }, /* strategy */ 96 { &vop_print_desc, mfs_print }, /* print */ 97 { &vop_islocked_desc, genfs_islocked }, /* islocked */ 98 { &vop_pathconf_desc, genfs_badop }, /* pathconf */ 99 { &vop_advlock_desc, genfs_badop }, /* advlock */ 100 { &vop_bwrite_desc, vn_bwrite }, /* bwrite */ 101 { &vop_putpages_desc, genfs_null_putpages }, /* putpages */ 102 { NULL, NULL } 103 }; 104 const struct vnodeopv_desc mfs_vnodeop_opv_desc = 105 { &mfs_vnodeop_p, mfs_vnodeop_entries }; 106 107 /* 108 * Vnode Operations. 109 * 110 * Open called to allow memory filesystem to initialize and 111 * validate before actual IO. Record our process identifier 112 * so we can tell when we are doing I/O to ourself. 113 */ 114 /* ARGSUSED */ 115 int 116 mfs_open(void *v) 117 { 118 struct vop_open_args /* { 119 struct vnode *a_vp; 120 int a_mode; 121 kauth_cred_t a_cred; 122 } */ *ap = v; 123 124 if (ap->a_vp->v_type != VBLK) { 125 panic("mfs_open not VBLK"); 126 /* NOTREACHED */ 127 } 128 return (0); 129 } 130 131 /* 132 * Pass I/O requests to the memory filesystem process. 133 */ 134 int 135 mfs_strategy(void *v) 136 { 137 struct vop_strategy_args /* { 138 struct vnode *a_vp; 139 struct buf *a_bp; 140 } */ *ap = v; 141 struct vnode *vp = ap->a_vp; 142 struct buf *bp = ap->a_bp; 143 struct mfsnode *mfsp; 144 145 if (vp->v_type != VBLK || vrefcnt(vp) == 0) 146 panic("mfs_strategy: bad dev"); 147 mfsp = VTOMFS(vp); 148 /* check for mini-root access */ 149 if (mfsp->mfs_proc == NULL) { 150 void *base; 151 152 base = (char *)mfsp->mfs_baseoff + (bp->b_blkno << DEV_BSHIFT); 153 if (bp->b_flags & B_READ) 154 memcpy(bp->b_data, base, bp->b_bcount); 155 else 156 memcpy(base, bp->b_data, bp->b_bcount); 157 bp->b_resid = 0; 158 biodone(bp); 159 } else if (mfsp->mfs_proc == curproc) { 160 mfs_doio(bp, mfsp->mfs_baseoff); 161 } else if (doing_shutdown) { 162 /* 163 * bitbucket I/O during shutdown. 164 * Note that reads should *not* happen here, but.. 165 */ 166 if (bp->b_flags & B_READ) 167 printf("warning: mfs read during shutdown\n"); 168 bp->b_resid = 0; 169 biodone(bp); 170 } else { 171 mutex_enter(&mfs_lock); 172 bufq_put(mfsp->mfs_buflist, bp); 173 cv_broadcast(&mfsp->mfs_cv); 174 mutex_exit(&mfs_lock); 175 } 176 return (0); 177 } 178 179 /* 180 * Memory file system I/O. 181 */ 182 void 183 mfs_doio(struct buf *bp, void *base) 184 { 185 186 base = (char *)base + (bp->b_blkno << DEV_BSHIFT); 187 if (bp->b_flags & B_READ) 188 bp->b_error = copyin(base, bp->b_data, bp->b_bcount); 189 else 190 bp->b_error = copyout(bp->b_data, base, bp->b_bcount); 191 if (bp->b_error == 0) 192 bp->b_resid = 0; 193 biodone(bp); 194 } 195 196 /* 197 * This is a noop, simply returning what one has been given. 198 */ 199 int 200 mfs_bmap(void *v) 201 { 202 struct vop_bmap_args /* { 203 struct vnode *a_vp; 204 daddr_t a_bn; 205 struct vnode **a_vpp; 206 daddr_t *a_bnp; 207 int *a_runp; 208 } */ *ap = v; 209 210 if (ap->a_vpp != NULL) 211 *ap->a_vpp = ap->a_vp; 212 if (ap->a_bnp != NULL) 213 *ap->a_bnp = ap->a_bn; 214 if (ap->a_runp != NULL) 215 *ap->a_runp = 0; 216 return (0); 217 } 218 219 /* 220 * Memory filesystem close routine 221 */ 222 /* ARGSUSED */ 223 int 224 mfs_close(void *v) 225 { 226 struct vop_close_args /* { 227 struct vnode *a_vp; 228 int a_fflag; 229 kauth_cred_t a_cred; 230 } */ *ap = v; 231 struct vnode *vp = ap->a_vp; 232 struct mfsnode *mfsp = VTOMFS(vp); 233 struct buf *bp; 234 int error; 235 236 /* 237 * Finish any pending I/O requests. 238 */ 239 mutex_enter(&mfs_lock); 240 while ((bp = bufq_get(mfsp->mfs_buflist)) != NULL) { 241 mutex_exit(&mfs_lock); 242 mfs_doio(bp, mfsp->mfs_baseoff); 243 mutex_enter(&mfs_lock); 244 } 245 mutex_exit(&mfs_lock); 246 /* 247 * On last close of a memory filesystem 248 * we must invalidate any in core blocks, so that 249 * we can, free up its vnode. 250 */ 251 if ((error = vinvalbuf(vp, V_SAVE, ap->a_cred, curlwp, 0, 0)) != 0) 252 return (error); 253 /* 254 * There should be no way to have any more uses of this 255 * vnode, so if we find any other uses, it is a panic. 256 */ 257 if (bufq_peek(mfsp->mfs_buflist) != NULL) 258 panic("mfs_close"); 259 /* 260 * Send a request to the filesystem server to exit. 261 */ 262 mutex_enter(&mfs_lock); 263 mfsp->mfs_shutdown = 1; 264 cv_broadcast(&mfsp->mfs_cv); 265 mutex_exit(&mfs_lock); 266 return (0); 267 } 268 269 /* 270 * Memory filesystem inactive routine 271 */ 272 /* ARGSUSED */ 273 int 274 mfs_inactive(void *v) 275 { 276 struct vop_inactive_v2_args /* { 277 struct vnode *a_vp; 278 } */ *ap = v; 279 struct vnode *vp = ap->a_vp; 280 struct mfsnode *mfsp = VTOMFS(vp); 281 282 if (bufq_peek(mfsp->mfs_buflist) != NULL) 283 panic("mfs_inactive: not inactive (mfs_buflist %p)", 284 bufq_peek(mfsp->mfs_buflist)); 285 286 return VOCALL(spec_vnodeop_p, VOFFSET(vop_inactive), ap); 287 } 288 289 /* 290 * Reclaim a memory filesystem devvp so that it can be reused. 291 */ 292 int 293 mfs_reclaim(void *v) 294 { 295 struct vop_reclaim_v2_args /* { 296 struct vnode *a_vp; 297 } */ *ap = v; 298 struct vnode *vp = ap->a_vp; 299 struct mfsnode *mfsp = VTOMFS(vp); 300 int refcnt; 301 302 mutex_enter(&mfs_lock); 303 vp->v_data = NULL; 304 refcnt = --mfsp->mfs_refcnt; 305 mutex_exit(&mfs_lock); 306 307 if (refcnt == 0) { 308 bufq_free(mfsp->mfs_buflist); 309 cv_destroy(&mfsp->mfs_cv); 310 kmem_free(mfsp, sizeof(*mfsp)); 311 } 312 313 return VOCALL(spec_vnodeop_p, VOFFSET(vop_reclaim), ap); 314 } 315 316 /* 317 * Print out the contents of an mfsnode. 318 */ 319 int 320 mfs_print(void *v) 321 { 322 struct vop_print_args /* { 323 struct vnode *a_vp; 324 } */ *ap = v; 325 struct mfsnode *mfsp = VTOMFS(ap->a_vp); 326 327 printf("tag VT_MFS, pid %d, base %p, size %ld\n", 328 (mfsp->mfs_proc != NULL) ? mfsp->mfs_proc->p_pid : 0, 329 mfsp->mfs_baseoff, mfsp->mfs_size); 330 return (0); 331 } 332
Indexes created Thu Sep 25 16:09:42 GMT 2025