path: root/drivers/nvdimm/btt.h
diff options
authorDan Williams <dan.j.williams@intel.com>2015-06-25 04:20:04 -0400
committerDan Williams <dan.j.williams@intel.com>2015-06-25 04:20:04 -0400
commit8c2f7e8658df1d3b7cbfa62706941d14c715823a (patch)
treeac93512841113f4d1d7a38d788ec73bb21e2d605 /drivers/nvdimm/btt.h
parent0ba1c634892b3590779803a701bcb82e8c32cc7a (diff)
libnvdimm: infrastructure for btt devices
NVDIMM namespaces, in addition to accepting "struct bio" based requests, also have the capability to perform byte-aligned accesses. By default only the bio/block interface is used. However, if another driver can make effective use of the byte-aligned capability it can claim namespace interface and use the byte-aligned ->rw_bytes() interface. The BTT driver is the initial first consumer of this mechanism to allow adding atomic sector update semantics to a pmem or blk namespace. This patch is the sysfs infrastructure to allow configuring a BTT instance for a namespace. Enabling that BTT and performing i/o is in a subsequent patch. Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/nvdimm/btt.h')
1 files changed, 45 insertions, 0 deletions
diff --git a/drivers/nvdimm/btt.h b/drivers/nvdimm/btt.h
new file mode 100644
index 000000000000..e8f6d8e0ddd3
--- /dev/null
+++ b/drivers/nvdimm/btt.h
@@ -0,0 +1,45 @@
+ * Block Translation Table library
+ * Copyright (c) 2014-2015, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ */
+#ifndef _LINUX_BTT_H
+#define _LINUX_BTT_H
+#include <linux/types.h>
+#define BTT_SIG_LEN 16
+struct btt_sb {
+ u8 signature[BTT_SIG_LEN];
+ u8 uuid[16];
+ u8 parent_uuid[16];
+ __le32 flags;
+ __le16 version_major;
+ __le16 version_minor;
+ __le32 external_lbasize;
+ __le32 external_nlba;
+ __le32 internal_lbasize;
+ __le32 internal_nlba;
+ __le32 nfree;
+ __le32 infosize;
+ __le64 nextoff;
+ __le64 dataoff;
+ __le64 mapoff;
+ __le64 logoff;
+ __le64 info2off;
+ u8 padding[3968];
+ __le64 checksum;

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