Please review the following patches and provide any comments or feedback.
Patch 1 of 9
Thanks,
mikem
block_dump.c | 202 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
block_dump.h | 29 ++++++++
2 files changed, 231 insertions(+)
--------------------------------------------------------------------------------
Description:
This patch adds the .c and .h files for the mid-level block_dump driver.
This driver will allow block device drivers to support diskdump while
offloading the dependencies of diskdump from the low-level driver.
--------------------------------------------------------------------------------
diff -burpN old/drivers/block/block_dump.c new/drivers/block/block_dump.c
--- old/drivers/block/block_dump.c 1969-12-31 19:00:00.000000000 -0500
+++ new/drivers/block/block_dump.c 2005-04-07 20:49:23.000000000 -0400
@@ -0,0 +1,202 @@
+
+/*
+ * Block dump driver for block drivers to support diskdump functionality wihtout
+ * dependening on diskdump driver.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/types.h>
+#include <linux/pci.h>
+#include <linux/kernel.h>
+#include <linux/blk.h>
+#include <linux/blkdev.h>
+#include <linux/fs.h>
+#include <linux/genhd.h>
+#include <linux/crc32.h>
+#include <linux/diskdump.h>
+#include <linux/diskdumplib.h>
+#include "block_dump.h"
+
+/* Embedded module documentation macros - see modules.h */
+MODULE_AUTHOR("Hewlett-Packard Company");
+MODULE_DESCRIPTION("Mid-level Block Driver for diskdump");
+MODULE_LICENSE("GPL");
+
+static uint32_t module_crc;
+
+/* function prototypes */
+static int block_dump_sanity_check(struct disk_dump_device *dump_device);
+static int block_dump_rw_block(struct disk_dump_partition *dump_part, int rw, unsigned long dump_block_nr, void *buf, int len);
+static int block_dump_quiesce(struct disk_dump_device *dump_device);
+static int block_dump_shutdown(struct disk_dump_device *dump_device);
+static void *block_dump_probe(kdev_t dev);
+static int block_dump_add_device(struct disk_dump_device *dump_device);
+static void block_dump_remove_device(struct disk_dump_device *dump_device);
+
+/*
+ * This MACRO is to get the starting address of blcok_device_operations_dump strucutre using blk_fops pointer * , which is a member of block_device_operations_dump structure
+ */
+#define BLOCK_OPS_EXT(blk_fops) container_of(blk_fops, block_device_operations_dump, blk_fops)
+
+static struct disk_dump_type block_dump_type = {
+ .probe = block_dump_probe,
+ .add_device = block_dump_add_device,
+ .remove_device = block_dump_remove_device,
+ .owner = THIS_MODULE,
+};
+
+static struct disk_dump_device_ops block_dump_device_ops = {
+ .sanity_check = block_dump_sanity_check,
+ .rw_block = block_dump_rw_block,
+ .quiesce = block_dump_quiesce,
+ .shutdown = block_dump_shutdown,
+};
+
+
+static int block_dump_shutdown(struct disk_dump_device *dump_device) {
+
+ device_info_t *device_info = dump_device->device;
+ block_device_operations_dump *blk_dev_ops = device_info->blk_dump_ops;
+
+ if ( blk_dev_ops->block_dump_ops->shutdown != NULL ) {
+ return blk_dev_ops->block_dump_ops->shutdown(device_info->device);
+ }
+
+ return -1;
+}
+
+static int block_dump_quiesce(struct disk_dump_device *dump_device) {
+
+ device_info_t *device_info = dump_device->device;
+ block_device_operations_dump *blk_dev_ops = device_info->blk_dump_ops;
+
+ if ( blk_dev_ops->block_dump_ops->quiesce == NULL ) {
+ return -1;
+ }
+
+ blk_dev_ops->block_dump_ops->quiesce(device_info->device);
+ diskdump_register_poll(device_info->device, (void *)blk_dev_ops->poll);
+
+ return 0;
+}
+
+static int block_dump_rw_block(struct disk_dump_partition *dump_part,
+ int rw, unsigned long dump_block_nr, void *buf, int len) {
+
+ device_info_t *device_info = ((struct disk_dump_device *)dump_part->device)->device;
+ block_device_operations_dump *blk_dev_ops = device_info->blk_dump_ops;
+ struct disk_dump_device *dump_device = dump_part->device;
+
+ if ( blk_dev_ops->block_dump_ops->rw_block != NULL ) {
+ return blk_dev_ops->block_dump_ops->rw_block(device_info->device, rw,
+ dump_block_nr, buf, len, dump_part->start_sect, dump_part->nr_sects);
+ }
+
+ return -1;
+}
+
+static int block_dump_sanity_check(struct disk_dump_device *dump_device){
+
+ device_info_t *device_info = dump_device->device;
+ block_device_operations_dump *blk_dev_ops = device_info->blk_dump_ops;
+
+ if (!check_crc_module()){
+ printk("<1>checksum error. block dump module may be compromised\n");
+ return -EINVAL;
+ }
+
+ if ( blk_dev_ops->block_dump_ops->sanity_check != NULL ) {
+ return blk_dev_ops->block_dump_ops->sanity_check(device_info->device);
+ }
+
+ return -1;
+}
+
+static void *block_dump_probe(kdev_t dev){
+ const struct block_device_operations *blk_fops;
+ struct block_device *blk_dev;
+ block_device_operations_dump *blk_dump_ops;
+ device_info_t *device_info;
+
+ set_crc_modules();
+ device_info = kmalloc(sizeof(device_info_t), GFP_KERNEL);
+
+ blk_dev = bdget( (dev_t)dev);
+ blk_fops = blk_dev->bd_op;
+
+ blk_dump_ops = BLOCK_OPS_EXT(blk_fops);
+
+ if (!blk_fops->diskdump)
+ {
+ printk("Dumpdevice Extended ops null\n");
+ return NULL;
+ }
+
+ if ( blk_dump_ops->block_probe != NULL ) {
+ device_info->device = blk_dump_ops->block_probe(dev);
+
+ device_info->blk_dump_ops = blk_dump_ops;
+ return device_info;
+ }
+
+ return NULL;
+}
+
+static int block_dump_add_device(struct disk_dump_device *dump_device){
+ device_info_t *device_info = dump_device->device;
+ block_device_operations_dump *blk_dev_ops = device_info->blk_dump_ops;
+
+ if(!memcpy(&dump_device->ops, &block_dump_device_ops, sizeof(struct disk_dump_device_ops)))
+ return -1;
+
+ if ( blk_dev_ops->block_add_device != NULL ) {
+ dump_device->max_blocks = blk_dev_ops->block_add_device(device_info->device);
+ }
+
+ return 0;
+}
+
+static void block_dump_remove_device(struct disk_dump_device *dump_device){
+}
+
+static int __init init_block_dump_module(void)
+{
+ int ret;
+
+ /* register with diskdump here. */
+ if ((ret = register_disk_dump_type(&block_dump_type)) < 0 ) {
+ printk("<1>Register of diskdump type failed\n");
+ return ret;
+ }
+
+ set_crc_modules();
+
+ return ret;
+}
+
+static void __exit cleanup_block_dump_module(void)
+{
+ if (unregister_disk_dump_type(&block_dump_type) < 0 )
+ printk("<1>Error unregistering diskdump\n");
+}
+
+module_init(init_block_dump_module);
+module_exit(cleanup_block_dump_module);
+
diff -burpN old/drivers/block/block_dump.h new/drivers/block/block_dump.h
--- old/drivers/block/block_dump.h 1969-12-31 19:00:00.000000000 -0500
+++ new/drivers/block/block_dump.h 2005-04-07 20:49:25.000000000 -0400
@@ -0,0 +1,29 @@
+
+#ifndef BLOCKDUMP_H
+#define BLOCKDUMP_H
+
+/*
+ * Extended block operations for dump for preserving binary compatibility.
+ */
+struct block_dump_ops {
+ int (*sanity_check)(void *device);
+ int (*rw_block)(void *device, int rw, unsigned long dump_block_nr, void *buf, int len, unsigned long start_sect, unsigned long nr_sects);
+ int (*quiesce)(void *device);
+ int (*shutdown)(void *device);
+};
+
+typedef struct __block_device_operations_dump {
+ struct block_device_operations blk_fops;
+ struct block_dump_ops *block_dump_ops;
+ void *(*block_probe)(kdev_t dev);
+ unsigned int (*block_add_device)(void *device);
+ unsigned long (*poll)(int ctlr);
+} block_device_operations_dump;
+
+typedef struct _device_info_t
+{
+ void *device;
+ void *blk_dump_ops;
+} device_info_t;
+
+#endif // BLOCKDUMP_H
This looks like a patch for Linux 2.4. Such major changes for the
2.4 tree don't make sense anymore, especially for functionality not
even in Linux 2.6.
On Mon, 2005-04-18 at 10:36 -0500, [email protected] wrote:
> Please review the following patches and provide any comments or feedback.
> Patch 1 of 9
what diskdump do you use?
Why do we even look at disk dump when kexec based dump can dump to disk
too and is otherwise more flexible and superior?
Maybe it's worth discussion that before doing major patches for.. well
potentially no good.
On Mon, 2005-04-18 at 10:36 -0500, [email protected] wrote:
> +
> +/*
> + * Extended block operations for dump for preserving binary compatibility.
> + */
> +struct block_dump_ops {
> + int (*sanity_check)(void *device);
> + int (*rw_block)(void *device, int rw, unsigned long dump_block_nr, void *buf, int len, unsigned long start_sect, unsigned long nr_sects);
> + int (*quiesce)(void *device);
> + int (*shutdown)(void *device);
> +};
this looks wrong. In linux we don't care about module ABI, and just go
for the clean solution instead! (eg in this case, just put the methods
in the block dev ops)
> From: Christoph Hellwig [mailto:[email protected]]
>
> This looks like a patch for Linux 2.4. Such major changes for the
> 2.4 tree don't make sense anymore, especially for
> functionality not even in Linux 2.6.
>
This is for 2.4, I should have specified that in the Subject line. We
did this work because of customer demand and a request from a vendor.
Marcelo, is this something that you be interested in adding to 2.4? If
not, I'll just submit this directly to the vendor.
Thanks,
mikem
>
On Mon, Apr 18, 2005 at 04:42:26PM +0100, Christoph Hellwig wrote:
> This looks like a patch for Linux 2.4. Such major changes for the
> 2.4 tree don't make sense anymore, especially for functionality not
> even in Linux 2.6.
Agreed.
On Mon, Apr 18, 2005 at 12:14:06PM -0500, Miller, Mike (OS Dev) wrote:
> > From: Christoph Hellwig [mailto:[email protected]]
> >
> > This looks like a patch for Linux 2.4. Such major changes for the
> > 2.4 tree don't make sense anymore, especially for
> > functionality not even in Linux 2.6.
> >
> This is for 2.4, I should have specified that in the Subject line. We
> did this work because of customer demand and a request from a vendor.
> Marcelo, is this something that you be interested in adding to 2.4? If
> not, I'll just submit this directly to the vendor.
Mike,
Nope, that does not look suitable for v2.4.x.