Greetings,
Part 4 of the EVMS core driver.
This file provides the Passthru pseudo-plugin, which simply recognizes
EVMS volume labels. It is always bound to the core driver instead of
being a full, separate plugin.
Kevin Corry
corryk@us.ibm.com
http://evms.sourceforge.net/
diff -Naur linux-2.5.41/drivers/evms/core/passthru.c linux-2.5.41-evms/drivers/evms/core/passthru.c
--- linux-2.5.41/drivers/evms/core/passthru.c Wed Dec 31 18:00:00 1969
+++ linux-2.5.41-evms/drivers/evms/core/passthru.c Thu Oct 10 11:16:58 2002
@@ -0,0 +1,373 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2000
+ *
+ * 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. 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+/*
+ * EVMS Volume Passthru Manager
+ *
+ * Passthru is a "special" EVMS plugin. It provides all of the services that
+ * a regular plugin provides (volume discovery/delete, I/O and ioctl handling)
+ * but it must always be loaded with the core. Thus, this plugin is not built
+ * as a separate kernel module (like the regular plugins). Instead, it is bound
+ * to the EVMS core module. It also does not have a module_init() or
+ * module_exit(). Instead, the EVMS core will call Passthru's init/exit
+ * functions manually when the core is loaded/unloaded. Also, since it is not a
+ * separate module, it will not do increments/decrements on the module reference
+ * count.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/config.h>
+#include <linux/bio.h>
+#include <linux/evms.h>
+
+#define LOG_PREFIX "passthru: "
+#define EVMS_PASSTHRU_ID 0
+
+static int passthru_discover(struct list_head *);
+static int passthru_delete(struct evms_logical_node *);
+static void passthru_submit_io(struct evms_logical_node *, struct bio *);
+static int passthru_ioctl(struct evms_logical_node *, struct inode *,
+ struct file *, unsigned int, unsigned long);
+static int passthru_init_io(struct evms_logical_node *, int, u64, u64,
+ void *);
+static int passthru_open(struct evms_logical_node *, struct inode *,
+ struct file *);
+static int passthru_release(struct evms_logical_node *, struct inode *,
+ struct file *);
+static int passthru_check_media_change(struct evms_logical_node *, kdev_t);
+static int passthru_revalidate(struct evms_logical_node *, kdev_t);
+static int passthru_quiesce(struct evms_logical_node *, int);
+static int passthru_get_geo(struct evms_logical_node *, u64 *, uint *,
+ uint *, u64 *);
+static int passthru_device_list(struct evms_logical_node *,
+ struct list_head *);
+static int passthru_device_status(struct evms_logical_node *, int *);
+
+static struct evms_plugin_fops fops = {
+ .discover = passthru_discover,
+ .delete = passthru_delete,
+ .submit_io = passthru_submit_io,
+ .sync_io = passthru_init_io,
+ .ioctl = passthru_ioctl,
+ .open = passthru_open,
+ .release = passthru_release,
+ .check_media_change = passthru_check_media_change,
+ .revalidate = passthru_revalidate,
+ .quiesce = passthru_quiesce,
+ .get_geo = passthru_get_geo,
+ .device_list = passthru_device_list,
+ .device_status = passthru_device_status
+};
+
+static struct evms_plugin_header plugin_header = {
+ .id = SetPluginID(IBM_OEM_ID,
+ EVMS_FEATURE,
+ EVMS_PASSTHRU_ID),
+ .version = {
+ .major = 1,
+ .minor = 1,
+ .patchlevel = 1
+ },
+ .fops = &fops
+};
+
+/*******************************/
+/* Discovery support functions */
+/*******************************/
+
+static int
+process_passthru_data(struct evms_logical_node **pp)
+{
+ int rc, size_in_sectors;
+ struct evms_logical_node *node, *new_node;
+
+ node = *pp;
+
+ size_in_sectors =
+ evms_cs_size_in_vsectors(sizeof (struct evms_feature_header));
+
+ /* allocate "parent" node */
+ rc = evms_cs_allocate_logical_node(&new_node);
+ if (rc) {
+ /* on any fatal error, delete the node */
+ int rc2 = DELETE(node);
+ if (rc2) {
+ LOG_DEFAULT("error(%d) attempting to delete node(%s)\n",
+ rc2, node->name);
+ }
+ return rc;
+ }
+ /* initialize "parent" node */
+ new_node->private = node;
+ new_node->flags = node->flags;
+ new_node->plugin = &plugin_header;
+ new_node->system_id = node->system_id;
+ new_node->block_size = node->block_size;
+ new_node->hardsector_size = node->hardsector_size;
+ new_node->total_vsectors = node->total_vsectors;
+ new_node->total_vsectors -= (size_in_sectors << 1) +
+ node->feature_header->alignment_padding;
+ new_node->volume_info = node->volume_info;
+ strcpy(new_node->name, node->name);
+ if (strlen(node->feature_header->object_name))
+ strcat(new_node->name,
+ node->feature_header->object_name);
+ else
+ strcat(new_node->name, "_Passthru");
+ /* return "parent" node to caller */
+ *pp = new_node;
+
+ LOG_DETAILS("feature header found on '%s', created '%s'.\n",
+ node->name, new_node->name);
+ /* we're done with the passthru feature headers
+ * so lets delete them now.
+ */
+ kfree(node->feature_header);
+ node->feature_header = NULL;
+ return 0;
+}
+
+/********** Required Plugin Functions **********/
+
+/**
+ * passthru_discover
+ **/
+static int
+passthru_discover(struct list_head *discover_list)
+{
+ struct evms_logical_node *node, *next_node;
+ struct list_head tmp_list_head;
+
+ INIT_LIST_HEAD(&tmp_list_head);
+ list_splice_init(discover_list, &tmp_list_head);
+ list_for_each_entry_safe(node, next_node, &tmp_list_head, discover) {
+ list_del_init(&node->discover);
+ if (!process_passthru_data(&node)) {
+ if (node) {
+ list_add_tail(&node->discover, discover_list);
+ }
+ }
+ }
+ return 0;
+}
+
+/**
+ * passthru_delete
+ **/
+static int
+passthru_delete(struct evms_logical_node *node)
+{
+ int rc;
+ struct evms_logical_node *p;
+
+ LOG_DETAILS("deleting '%s'.\n", node->name);
+
+ p = node->private;
+ rc = DELETE(p);
+ if (!rc) {
+ evms_cs_deallocate_logical_node(node);
+ } else {
+ LOG_DEFAULT("error(%d) attempting to delete node(%s).\n",
+ rc, node->name);
+ }
+ return rc;
+}
+
+/**
+ * passthru_submit_io
+ **/
+static void
+passthru_submit_io(struct evms_logical_node *node, struct bio *bio)
+{
+ if (bio->bi_sector + bio_sectors(bio) <= node->total_vsectors) {
+ SUBMIT_IO((struct evms_logical_node *) (node->private), bio);
+ } else {
+ LOG_SERIOUS("I/O request on (%s) at rsector ("PFU64") "
+ "beyond boundary ("PFU64").\n",
+ node->name, node->total_vsectors - 1,
+ (u64) bio->bi_sector);
+ bio_io_error(bio, bio->bi_size);
+ }
+}
+
+/**
+ * passthru_ioctl
+ **/
+static int
+passthru_ioctl(struct evms_logical_node *node, struct inode *inode,
+ struct file *file, unsigned int cmd, unsigned long arg)
+{
+ return IOCTL(((struct evms_logical_node *) (node->private)),
+ inode, file, cmd, arg);
+}
+
+/**
+ * passthru_init_io
+ **/
+static int
+passthru_init_io(struct evms_logical_node *node, int rw,
+ u64 sect_nr, u64 num_sects, void *buf_addr)
+{
+ if (sect_nr + num_sects > node->total_vsectors) {
+ return -EINVAL;
+ }
+
+ return INIT_IO(((struct evms_logical_node *) (node->private)),
+ rw, sect_nr, num_sects, buf_addr);
+}
+
+/**
+ * passthru_open - route operation to node
+ * @node: target node
+ * @inode: VFS required parameter
+ * @file: VFS required parameter
+ *
+ * returns:
+ * 0 on success
+ * error code otherwise
+ */
+static int
+passthru_open(struct evms_logical_node *node,
+ struct inode *inode, struct file *file)
+{
+ return OPEN((struct evms_logical_node *)node->private, inode, file);
+}
+
+/**
+ * passthru_release - route operation to node
+ * @node: target node
+ * @inode: VFS required parameter
+ * @file: VFS required parameter
+ *
+ * returns:
+ * 0 on success
+ * error code otherwise
+ */
+static int
+passthru_release(struct evms_logical_node *node,
+ struct inode *inode, struct file *file)
+{
+ return CLOSE((struct evms_logical_node *)node->private, inode, file);
+}
+
+/**
+ * passthru_check_media_change - route operation to node
+ * @node: target node
+ * @dev: VFS required parameter
+ *
+ * returns:
+ * 0 on no change detected,
+ * 1 on change detected,
+ * error code otherwise
+ */
+static int
+passthru_check_media_change(struct evms_logical_node *node, kdev_t dev)
+{
+ return CHECK_MEDIA_CHANGE((struct evms_logical_node *)node->private, dev);
+}
+
+/**
+ * passthru_revalidate - route operation to node
+ * @node: target node
+ * @dev: VFS required parameter
+ *
+ * returns:
+ * 0 on success
+ * error code otherwise
+ */
+static int
+passthru_revalidate(struct evms_logical_node *node, kdev_t dev)
+{
+ return REVALIDATE((struct evms_logical_node *)node->private, dev);
+}
+
+/**
+ * passthru_quiesce - route operation to node
+ * @node: target node
+ * @dev: VFS required parameter
+ *
+ * returns:
+ * 0 on success
+ * error code otherwise
+ */
+static int
+passthru_quiesce(struct evms_logical_node *node, int command)
+{
+ return QUIESCE((struct evms_logical_node *)node->private, command);
+}
+
+/**
+ * passthru_get_geo - route operation to node
+ * @node: target node
+ * @dev: VFS required parameter
+ *
+ * returns:
+ * 0 on success
+ * error code otherwise
+ */
+static int
+passthru_get_geo(struct evms_logical_node *node, u64 *cylinders,
+ uint *heads, uint *sects, u64 *start)
+{
+ return GET_GEO((struct evms_logical_node *)node->private,
+ cylinders, heads, sects, start);
+}
+
+/**
+ * passthru_device_list - route operation to node
+ * @node: target node
+ * @dev: VFS required parameter
+ *
+ * returns:
+ * 0 on success
+ * error code otherwise
+ */
+static int
+passthru_device_list(struct evms_logical_node *node, struct list_head *list)
+{
+ return DEVICE_LIST((struct evms_logical_node *)node->private, list);
+}
+
+/**
+ * passthru_device_status - route operation to node
+ * @node: target node
+ * @dev: VFS required parameter
+ *
+ * returns:
+ * 0 on success
+ * error code otherwise
+ */
+static int
+passthru_device_status(struct evms_logical_node *node, int *status)
+{
+ return DEVICE_STATUS((struct evms_logical_node *)node->private,
+ status);
+}
+
+int
+evms_passthru_init(void)
+{
+ return evms_cs_register_plugin(&plugin_header);
+}
+
+void
+evms_passthru_exit(void)
+{
+ evms_cs_unregister_plugin(&plugin_header);
+}
+
-
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This archive was generated by hypermail 2b29 : Tue Oct 15 2002 - 22:00:38 EST