Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/drivers/md/dm-target.c b/drivers/md/dm-target.c
new file mode 100644
index 0000000..aecd9e0
--- /dev/null
+++ b/drivers/md/dm-target.c
@@ -0,0 +1,196 @@
+/*
+ * Copyright (C) 2001 Sistina Software (UK) Limited
+ *
+ * This file is released under the GPL.
+ */
+
+#include "dm.h"
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kmod.h>
+#include <linux/bio.h>
+#include <linux/slab.h>
+
+struct tt_internal {
+ struct target_type tt;
+
+ struct list_head list;
+ long use;
+};
+
+static LIST_HEAD(_targets);
+static DECLARE_RWSEM(_lock);
+
+#define DM_MOD_NAME_SIZE 32
+
+static inline struct tt_internal *__find_target_type(const char *name)
+{
+ struct tt_internal *ti;
+
+ list_for_each_entry (ti, &_targets, list)
+ if (!strcmp(name, ti->tt.name))
+ return ti;
+
+ return NULL;
+}
+
+static struct tt_internal *get_target_type(const char *name)
+{
+ struct tt_internal *ti;
+
+ down_read(&_lock);
+
+ ti = __find_target_type(name);
+ if (ti) {
+ if ((ti->use == 0) && !try_module_get(ti->tt.module))
+ ti = NULL;
+ else
+ ti->use++;
+ }
+
+ up_read(&_lock);
+ return ti;
+}
+
+static void load_module(const char *name)
+{
+ request_module("dm-%s", name);
+}
+
+struct target_type *dm_get_target_type(const char *name)
+{
+ struct tt_internal *ti = get_target_type(name);
+
+ if (!ti) {
+ load_module(name);
+ ti = get_target_type(name);
+ }
+
+ return ti ? &ti->tt : NULL;
+}
+
+void dm_put_target_type(struct target_type *t)
+{
+ struct tt_internal *ti = (struct tt_internal *) t;
+
+ down_read(&_lock);
+ if (--ti->use == 0)
+ module_put(ti->tt.module);
+
+ if (ti->use < 0)
+ BUG();
+ up_read(&_lock);
+
+ return;
+}
+
+static struct tt_internal *alloc_target(struct target_type *t)
+{
+ struct tt_internal *ti = kmalloc(sizeof(*ti), GFP_KERNEL);
+
+ if (ti) {
+ memset(ti, 0, sizeof(*ti));
+ ti->tt = *t;
+ }
+
+ return ti;
+}
+
+
+int dm_target_iterate(void (*iter_func)(struct target_type *tt,
+ void *param), void *param)
+{
+ struct tt_internal *ti;
+
+ down_read(&_lock);
+ list_for_each_entry (ti, &_targets, list)
+ iter_func(&ti->tt, param);
+ up_read(&_lock);
+
+ return 0;
+}
+
+int dm_register_target(struct target_type *t)
+{
+ int rv = 0;
+ struct tt_internal *ti = alloc_target(t);
+
+ if (!ti)
+ return -ENOMEM;
+
+ down_write(&_lock);
+ if (__find_target_type(t->name))
+ rv = -EEXIST;
+ else
+ list_add(&ti->list, &_targets);
+
+ up_write(&_lock);
+ if (rv)
+ kfree(ti);
+ return rv;
+}
+
+int dm_unregister_target(struct target_type *t)
+{
+ struct tt_internal *ti;
+
+ down_write(&_lock);
+ if (!(ti = __find_target_type(t->name))) {
+ up_write(&_lock);
+ return -EINVAL;
+ }
+
+ if (ti->use) {
+ up_write(&_lock);
+ return -ETXTBSY;
+ }
+
+ list_del(&ti->list);
+ kfree(ti);
+
+ up_write(&_lock);
+ return 0;
+}
+
+/*
+ * io-err: always fails an io, useful for bringing
+ * up LVs that have holes in them.
+ */
+static int io_err_ctr(struct dm_target *ti, unsigned int argc, char **args)
+{
+ return 0;
+}
+
+static void io_err_dtr(struct dm_target *ti)
+{
+ /* empty */
+}
+
+static int io_err_map(struct dm_target *ti, struct bio *bio,
+ union map_info *map_context)
+{
+ return -EIO;
+}
+
+static struct target_type error_target = {
+ .name = "error",
+ .version = {1, 0, 1},
+ .ctr = io_err_ctr,
+ .dtr = io_err_dtr,
+ .map = io_err_map,
+};
+
+int __init dm_target_init(void)
+{
+ return dm_register_target(&error_target);
+}
+
+void dm_target_exit(void)
+{
+ if (dm_unregister_target(&error_target))
+ DMWARN("error target unregistration failed");
+}
+
+EXPORT_SYMBOL(dm_register_target);
+EXPORT_SYMBOL(dm_unregister_target);