[PATCH 20/50] mars: add new file drivers/block/mars/xio_bricks/xio.c

Thomas Schoebel-Theuer
2014-07-01T21:48:03Z

drivers/block/mars/xio_bricks/xio.c | 183 ++++++++++++++++++++++++++++++++++++
1 file changed, 183 insertions(+)
create mode 100644 drivers/block/mars/xio_bricks/xio.c

diff --git a/drivers/block/mars/xio_bricks/xio.c b/drivers/block/mars/xio_bricks/xio.c
new file mode 100644
index 0000000..cc13478
--- /dev/null
+++ b/drivers/block/mars/xio_bricks/xio.c
@@ -0,0 +1,183 @@
+/* (c) 2010 Thomas Schoebel-Theuer / 1&1 Internet AG */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/utsname.h>
+
+#include <linux/xio.h>
+
+/************************************************************/
+
+/* infrastructure */
+
+struct banning xio_global_ban = {};
+EXPORT_SYMBOL_GPL(xio_global_ban);
+atomic_t xio_global_io_flying = ATOMIC_INIT(0);
+EXPORT_SYMBOL_GPL(xio_global_io_flying);
+
+static char *id;
+
+/* TODO: better use MAC addresses (or motherboard IDs where available).
+ * Or, at least, some checks for MAC addresses should be recorded / added.
+ * When the nodename is misconfigured, data might be scrambled.
+ * MAC addresses should be more secure.
+ * In ideal case, further checks should be added to prohibit accidental
+ * name clashes.
+ */
+char *my_id(void)
+{
+ struct new_utsname *u;
+
+ if (!id) {
+ /* down_read(&uts_sem); // FIXME: this is currenty not EXPORTed from the kernel! */
+ u = utsname();
+ if (u)
+ id = brick_strdup(u->nodename);
+ /* up_read(&uts_sem); */
+ }
+ return id;
+}
+EXPORT_SYMBOL_GPL(my_id);
+
+/************************************************************/
+
+/* object stuff */
+
+const struct generic_object_type aio_type = {
+ .object_type_name = "aio",
+ .default_size = sizeof(struct aio_object),
+ .object_type_nr = OBJ_TYPE_AIO,
+};
+EXPORT_SYMBOL_GPL(aio_type);
+
+/************************************************************/
+
+/* brick stuff */
+
+/*******************************************************************/
+
+/* meta descriptions */
+
+const struct meta xio_info_meta[] = {
+ META_INI(current_size, struct xio_info, FIELD_INT),
+ META_INI(tf_align, struct xio_info, FIELD_INT),
+ META_INI(tf_min_size, struct xio_info, FIELD_INT),
+ {}
+};
+EXPORT_SYMBOL_GPL(xio_info_meta);
+
+const struct meta xio_aio_meta[] = {
+ META_INI(_object_cb.cb_error, struct aio_object, FIELD_INT),
+ META_INI(io_pos, struct aio_object, FIELD_INT),
+ META_INI(io_len, struct aio_object, FIELD_INT),
+ META_INI(io_may_write, struct aio_object, FIELD_INT),
+ META_INI(io_prio, struct aio_object, FIELD_INT),
+ META_INI(io_cs_mode, struct aio_object, FIELD_INT),
+ META_INI(io_timeout, struct aio_object, FIELD_INT),
+ META_INI(io_total_size, struct aio_object, FIELD_INT),
+ META_INI(io_checksum, struct aio_object, FIELD_RAW),
+ META_INI(io_flags, struct aio_object, FIELD_INT),
+ META_INI(io_rw, struct aio_object, FIELD_INT),
+ META_INI(io_id, struct aio_object, FIELD_INT),
+ META_INI(io_skip_sync, struct aio_object, FIELD_INT),
+ {}
+};
+EXPORT_SYMBOL_GPL(xio_aio_meta);
+
+const struct meta xio_timespec_meta[] = {
+ META_INI_TRANSFER(tv_sec, struct timespec, FIELD_UINT, 8),
+ META_INI_TRANSFER(tv_nsec, struct timespec, FIELD_UINT, 4),
+ {}
+};
+EXPORT_SYMBOL_GPL(xio_timespec_meta);
+
+/************************************************************/
+
+/* crypto stuff */
+
+#include <linux/scatterlist.h>
+#include <linux/crypto.h>
+
+static struct crypto_hash *xio_tfm;
+static struct semaphore tfm_sem = __SEMAPHORE_INITIALIZER(tfm_sem, 1);
+int xio_digest_size = 0;
+EXPORT_SYMBOL_GPL(xio_digest_size);
+
+void xio_digest(unsigned char *digest, void *data, int len)
+{
+ struct hash_desc desc = {
+ .tfm = xio_tfm,
+ .flags = 0,
+ };
+ struct scatterlist sg;
+
+ memset(digest, 0, xio_digest_size);
+
+ /* TODO: use per-thread instance, omit locking */
+ down(&tfm_sem);
+
+ crypto_hash_init(&desc);
+ sg_init_table(&sg, 1);
+ sg_set_buf(&sg, data, len);
+ crypto_hash_update(&desc, &sg, sg.length);
+ crypto_hash_final(&desc, digest);
+ up(&tfm_sem);
+}
+EXPORT_SYMBOL_GPL(xio_digest);
+
+void aio_checksum(struct aio_object *aio)
+{
+ unsigned char checksum[xio_digest_size];
+ int len;
+
+ if (aio->io_cs_mode <= 0 || !aio->io_data)
+ goto out_return;
+ xio_digest(checksum, aio->io_data, aio->io_len);
+
+ len = sizeof(aio->io_checksum);
+ if (len > xio_digest_size)
+ len = xio_digest_size;
+ memcpy(&aio->io_checksum, checksum, len);
+out_return:;
+}
+EXPORT_SYMBOL_GPL(aio_checksum);
+
+/*******************************************************************/
+
+/* init stuff */
+
+int __init init_xio(void)
+{
+ XIO_INF("init_xio()\n");
+
+ xio_tfm = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC);
+ if (!xio_tfm) {
+ XIO_ERR("cannot alloc crypto hash\n");
+ return -ENOMEM;
+ }
+ if (IS_ERR(xio_tfm)) {
+ XIO_ERR("alloc crypto hash failed, status = %d\n", (int)PTR_ERR(xio_tfm));
+ return PTR_ERR(xio_tfm);
+ }
+ xio_digest_size = crypto_hash_digestsize(xio_tfm);
+ XIO_INF("digest_size = %d\n", xio_digest_size);
+
+ return 0;
+}
+
+void exit_xio(void)
+{
+ XIO_INF("exit_xio()\n");
+
+ if (xio_tfm)
+ crypto_free_hash(xio_tfm);
+
+ if (id) {
+ brick_string_free(id);
+ id = NULL;
+ }
+}
--
2.0.0