Source-Changes-HG archive
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]
[src/trunk]: src/sys/modules/examples Add a new example kernel module: mapper
details: https://anonhg.NetBSD.org/src/rev/4cee463e47d4
branches: trunk
changeset: 447589:4cee463e47d4
user: kamil <kamil%NetBSD.org@localhost>
date: Thu Jan 17 20:47:42 2019 +0000
description:
Add a new example kernel module: mapper
Basic implementation of mmap.
Submitted by Akul Pillai.
diffstat:
sys/modules/examples/Makefile | 3 +-
sys/modules/examples/README | 6 +-
sys/modules/examples/mapper/Makefile | 17 +++
sys/modules/examples/mapper/cmd_mapper.c | 64 ++++++++++++++
sys/modules/examples/mapper/mapper.c | 141 +++++++++++++++++++++++++++++++
5 files changed, 229 insertions(+), 2 deletions(-)
diffs (277 lines):
diff -r 57705bdaad33 -r 4cee463e47d4 sys/modules/examples/Makefile
--- a/sys/modules/examples/Makefile Thu Jan 17 20:36:51 2019 +0000
+++ b/sys/modules/examples/Makefile Thu Jan 17 20:47:42 2019 +0000
@@ -1,4 +1,4 @@
-# $NetBSD: Makefile,v 1.6 2018/05/29 16:53:56 kamil Exp $
+# $NetBSD: Makefile,v 1.7 2019/01/17 20:47:42 kamil Exp $
.include <bsd.own.mk>
@@ -6,6 +6,7 @@
SUBDIR+= hello
#SUBDIR+= luahello # Nothing to build here, only text files
SUBDIR+= luareadhappy # Needs an additional Lua script
+SUBDIR+= mapper # Needs an additional helper program
SUBDIR+= panic_string # Crashes the system
SUBDIR+= ping # Needs an additional helper program
SUBDIR+= properties
diff -r 57705bdaad33 -r 4cee463e47d4 sys/modules/examples/README
--- a/sys/modules/examples/README Thu Jan 17 20:36:51 2019 +0000
+++ b/sys/modules/examples/README Thu Jan 17 20:47:42 2019 +0000
@@ -1,4 +1,4 @@
- $NetBSD: README,v 1.8 2018/05/29 16:53:56 kamil Exp $
+ $NetBSD: README,v 1.9 2019/01/17 20:47:42 kamil Exp $
Kernel Developer's Manual
@@ -10,6 +10,7 @@
* hello - the simplest `hello world' module
* luahello - the simplest `hello world' Lua module
* luareadhappy - demonstrates calling Lua code from C
+ * mapper - basic implementation of mmap
* panic_string - shows how panic is being called through a device
* ping - basic ioctl(9)
* properties - handle incoming properties during the module load
@@ -66,5 +67,8 @@
The panic_string module first appeared in NetBSD 9.0 and was authored by
Harry Pantazis.
+ The mapper module first appeared in NetBSD 9.0 and was authored by
+ Akul Pillai.
+
AUTHORS
This document was written by Kamil Rytarowski.
diff -r 57705bdaad33 -r 4cee463e47d4 sys/modules/examples/mapper/Makefile
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/sys/modules/examples/mapper/Makefile Thu Jan 17 20:47:42 2019 +0000
@@ -0,0 +1,17 @@
+# $NetBSD: Makefile,v 1.1 2019/01/17 20:47:42 kamil Exp $
+
+.include "../Makefile.inc"
+
+#S?= /usr/src/sys
+
+KMOD= mapper
+SRCS= mapper.c
+
+.include <bsd.kmodule.mk>
+
+# To make use of this module, you'll need to separately build the
+# cmd_mapper program, with a Makefile similar to
+#
+# MKMAN= NO
+# PROG= cmd_mapper
+# .include <bsd.prog.mk>
diff -r 57705bdaad33 -r 4cee463e47d4 sys/modules/examples/mapper/cmd_mapper.c
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/sys/modules/examples/mapper/cmd_mapper.c Thu Jan 17 20:47:42 2019 +0000
@@ -0,0 +1,64 @@
+/* $NetBSD: cmd_mapper.c,v 1.1 2019/01/17 20:47:42 kamil Exp $ */
+
+/*-
+ * Copyright (c) 2019 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__RCSID("$NetBSD: cmd_mapper.c,v 1.1 2019/01/17 20:47:42 kamil Exp $");
+
+#include <sys/mman.h>
+
+#include <err.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#define _PATH_DEV_MAPPER "/dev/mapper"
+
+int main(int argc, char **argv)
+{
+ int devfd;
+ char *map = NULL;
+
+ if ((devfd = open(_PATH_DEV_MAPPER, O_RDONLY)) == -1)
+ err(EXIT_FAILURE, "Cannot open %s", _PATH_DEV_MAPPER);
+
+ map = (char *)(mmap(0, sysconf(_SC_PAGESIZE), PROT_READ, MAP_SHARED,
+ devfd, 0));
+ if (map == MAP_FAILED)
+ err(EXIT_FAILURE, "Mapping failed");
+
+ printf("Message from device: %s\n",map);
+
+ if (munmap(map, sysconf(_SC_PAGESIZE)) == -1)
+ err(EXIT_FAILURE, "Unmap failed");
+
+ if (close(devfd) == -1)
+ err(EXIT_FAILURE, "Cannot close %s", _PATH_DEV_MAPPER);
+
+ return EXIT_SUCCESS;
+}
diff -r 57705bdaad33 -r 4cee463e47d4 sys/modules/examples/mapper/mapper.c
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/sys/modules/examples/mapper/mapper.c Thu Jan 17 20:47:42 2019 +0000
@@ -0,0 +1,141 @@
+/* $NetBSD: mapper.c,v 1.1 2019/01/17 20:47:42 kamil Exp $ */
+
+/*-
+ * Copyright (c) 2019 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__KERNEL_RCSID(0, "$NetBSD: mapper.c,v 1.1 2019/01/17 20:47:42 kamil Exp $");
+
+#include <sys/param.h>
+#include <sys/conf.h>
+#include <sys/device.h>
+#include <sys/kernel.h>
+#include <sys/kmem.h>
+#include <sys/module.h>
+#include <sys/systm.h>
+
+#include <uvm/uvm.h>
+
+/*
+ * Creating a device /dev/mapper for demonstration.
+ * To use this device you need to do:
+ * mknod /dev/mapper c 210 0
+ *
+ */
+
+dev_type_open(mapper_open);
+dev_type_close(mapper_close);
+dev_type_mmap(mapper_mmap);
+
+static struct cdevsw mapper_cdevsw = {
+ .d_open = mapper_open,
+ .d_close = mapper_close,
+ .d_read = noread,
+ .d_write = nowrite,
+ .d_ioctl = noioctl,
+ .d_stop = nostop,
+ .d_tty = notty,
+ .d_poll = nopoll,
+ .d_mmap = mapper_mmap,
+ .d_kqfilter = nokqfilter,
+ .d_discard = nodiscard,
+ .d_flag = D_OTHER
+};
+
+struct mapper_softc {
+ int refcnt;
+ char *buffer;
+};
+
+static struct mapper_softc sc;
+
+int
+mapper_open(dev_t self __unused, int flag __unused, int mode __unused,
+ struct lwp *l __unused)
+{
+ if (sc.refcnt > 0)
+ return EBUSY;
+ ++sc.refcnt;
+ sc.buffer = kmem_zalloc(PAGE_SIZE, KM_SLEEP);
+ snprintf(sc.buffer, PAGE_SIZE, "Hey There!");
+ return 0;
+}
+
+int
+mapper_close(dev_t self __unused, int flag __unused, int mode __unused,
+ struct lwp *l __unused)
+{
+ kmem_free(sc.buffer, PAGE_SIZE);
+ --sc.refcnt;
+ return 0;
+}
+
+/*
+ * Here, pmap_extract() is used to extract the mapping from the specified
+ * physical map for the provided virtual address, where pmap_kernel() points
+ * to the kernel pmap.
+ */
+
+paddr_t
+mapper_mmap(dev_t dev, off_t off, int prot)
+{
+ paddr_t pa;
+
+ if (off & PAGE_MASK)
+ return (paddr_t)-1;
+ if (prot != VM_PROT_READ)
+ return (paddr_t)-1;
+ if (pmap_extract(pmap_kernel(), (vaddr_t)sc.buffer, &pa))
+ return (paddr_t)atop(pa);
+
+ return (paddr_t)-1;
+}
+
+MODULE(MODULE_CLASS_MISC, mapper, NULL);
+
+static int
+mapper_modcmd(modcmd_t cmd, void *arg __unused)
+{
+ /* The major should be verified and changed if needed to avoid
+ * conflicts with other devices. */
+ int cmajor = 210, bmajor = -1;
+
+ switch (cmd) {
+ case MODULE_CMD_INIT:
+ if (devsw_attach("mapper", NULL, &bmajor, &mapper_cdevsw,
+ &cmajor))
+ return ENXIO;
+ return 0;
+ case MODULE_CMD_FINI:
+ if (sc.refcnt > 0)
+ return EBUSY;
+ devsw_detach(NULL, &mapper_cdevsw);
+ return 0;
+ default:
+ return ENOTTY;
+ }
+ return 0;
+}
Home |
Main Index |
Thread Index |
Old Index