inst_sync.c revision 0a653502ce7060b491de569a1991825128724441
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * CDDL HEADER START
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * The contents of this file are subject to the terms of the
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * Common Development and Distribution License (the "License").
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * You may not use this file except in compliance with the License.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * See the License for the specific language governing permissions
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * and limitations under the License.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * When distributing Covered Code, include this CDDL HEADER in each
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * If applicable, add the following below this CDDL HEADER, with the
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a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * information: Portions Copyright [yyyy] [name of copyright owner]
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * CDDL HEADER END
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * Use is subject to license terms.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster#pragma ident "%Z%%M% %I% %E% SMI"
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * Syscall to write out the instance number data structures to
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * stable storage.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * Userland sees:
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * int inst_sync(pathname, flags);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * Returns zero if instance number information was successfully
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * written to 'pathname', -1 plus error code in errno otherwise.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * POC notes:
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * - This could be done as a case of the modctl(2) system call
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * though the ability to have it load and unload would disappear.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * - 'flags' have either of two meanings:
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * INST_SYNC_IF_REQUIRED 'pathname' will be written if there
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * has been a change in the kernel's
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * internal view of instance number
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * information
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * INST_SYNC_ALWAYS 'pathname' will be written even if
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * the kernel's view hasn't changed.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * - Maybe we should pass through two filenames - one to create,
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * and the other as the 'final' target i.e. do the rename of
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * /etc/instance.new -> /etc/instance in the kernel.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Fosterstatic int in_sync_sys(char *pathname, uint_t flags);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster SE_ARGC | SE_32RVAL1, /* c-style calling, 32-bit return value */
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster (krwlock_t *)0 /* rw lock allocated/used by framework */
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster &mod_syscallops, "instance binding syscall", &in_sync_sysent
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster &mod_syscallops32, "32-bit instance binding syscall", &in_sync_sysent
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * We must have sufficient privilege to do this, since we lock critical
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * data structures whilst we're doing it ..
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster if ((error = secpolicy_sys_devices(CRED())) != 0)
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster if (flags != INST_SYNC_ALWAYS && flags != INST_SYNC_IF_REQUIRED)
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * Only one process is allowed to get the state of the instance
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * number assignments on the system at any given time.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * Recreate the instance file only if the device tree has changed
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * or if the caller explicitly requests so.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster if (e_ddi_instance_is_clean() && flags != INST_SYNC_ALWAYS) {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * Create an instance file for writing, giving it a mode that
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * will only permit reading. Note that we refuse to overwrite
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * an existing file.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * So far so good. We're singly threaded, the vnode is beckoning
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * so let's get on with it. Any error, and we just give up and
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * hand the first error we get back to userland.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * If there was any sort of error, we deliberately go and
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * remove the file we just created so that any attempts to
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * use it will quickly fail.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster (void) vn_remove(pathname, UIO_USERSPACE, RMFILE);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * At the risk of reinventing stdio ..
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Fostertypedef struct _File {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Fosterin_write(struct vnode *vp, offset_t *vo, caddr_t buf, int count)
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster error = vn_rdwr(UIO_WRITE, vp, buf, count, *vo,
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster error = VOP_CLOSE(fp->vp, FCREAT, 1, (offset_t)0, CRED(), NULL);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster error = in_write(fp->vp, &fp->voffset, fp->buf, fp->count);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster error = VOP_FSYNC(fp->vp, FSYNC, CRED(), NULL);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster error = in_write(fp->vp, &fp->voffset, fp->buf,
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * External linkage
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * XXX what is the maximum length of the name of a driver? Must be maximum
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * XXX file name length (find the correct constant and substitute for this one
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Fosterstatic char linebuffer[MAXPATHLEN + 1 + 1 + 1 + 1 + 10 + 1 + DRVNAMELEN];
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * XXX Maybe we should just write 'in_fprintf' instead ..
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster (void) sprintf(this, "/%s@%s", np->in_node_name,
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster for (dp = np->in_drivers; dp; dp = dp->ind_next_drv) {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * Flushing IN_PROVISIONAL could result in duplicate
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * Flushing IN_UNKNOWN results in instance -1
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster (void) sprintf(next, "\" %d \"%s\"\n", inst_val,
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * Walk the instance tree, writing out what we find.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * There's some fairly nasty sharing of buffers in this
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * bit of code, so be careful out there when you're
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * rewriting it ..
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster * Place a bossy comment at the beginning of the file.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster "#\n#\tCaution! This file contains critical kernel state\n#\n");