v4.19.13 snapshot.
diff --git a/fs/exofs/common.h b/fs/exofs/common.h
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+++ b/fs/exofs/common.h
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+/*
+ * common.h - Common definitions for both Kernel and user-mode utilities
+ *
+ * Copyright (C) 2005, 2006
+ * Avishay Traeger (avishay@gmail.com)
+ * Copyright (C) 2008, 2009
+ * Boaz Harrosh <ooo@electrozaur.com>
+ *
+ * Copyrights for code taken from ext2:
+ *     Copyright (C) 1992, 1993, 1994, 1995
+ *     Remy Card (card@masi.ibp.fr)
+ *     Laboratoire MASI - Institut Blaise Pascal
+ *     Universite Pierre et Marie Curie (Paris VI)
+ *     from
+ *     linux/fs/minix/inode.c
+ *     Copyright (C) 1991, 1992  Linus Torvalds
+ *
+ * This file is part of exofs.
+ *
+ * exofs 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.  Since it is based on ext2, and the only
+ * valid version of GPL for the Linux kernel is version 2, the only valid
+ * version of GPL for exofs is version 2.
+ *
+ * exofs 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 exofs; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#ifndef __EXOFS_COM_H__
+#define __EXOFS_COM_H__
+
+#include <linux/types.h>
+
+#include <scsi/osd_attributes.h>
+#include <scsi/osd_initiator.h>
+#include <scsi/osd_sec.h>
+
+/****************************************************************************
+ * Object ID related defines
+ * NOTE: inode# = object ID - EXOFS_OBJ_OFF
+ ****************************************************************************/
+#define EXOFS_MIN_PID   0x10000	/* Smallest partition ID */
+#define EXOFS_OBJ_OFF	0x10000	/* offset for objects */
+#define EXOFS_SUPER_ID	0x10000	/* object ID for on-disk superblock */
+#define EXOFS_DEVTABLE_ID 0x10001 /* object ID for on-disk device table */
+#define EXOFS_ROOT_ID	0x10002	/* object ID for root directory */
+
+/* exofs Application specific page/attribute */
+/* Inode attrs */
+# define EXOFS_APAGE_FS_DATA	(OSD_APAGE_APP_DEFINED_FIRST + 3)
+# define EXOFS_ATTR_INODE_DATA	1
+# define EXOFS_ATTR_INODE_FILE_LAYOUT	2
+# define EXOFS_ATTR_INODE_DIR_LAYOUT	3
+/* Partition attrs */
+# define EXOFS_APAGE_SB_DATA	(0xF0000000U + 3)
+# define EXOFS_ATTR_SB_STATS	1
+
+/*
+ * The maximum number of files we can have is limited by the size of the
+ * inode number.  This is the largest object ID that the file system supports.
+ * Object IDs 0, 1, and 2 are always in use (see above defines).
+ */
+enum {
+	EXOFS_MAX_INO_ID = (sizeof(ino_t) * 8 == 64) ? ULLONG_MAX :
+					(1ULL << (sizeof(ino_t) * 8ULL - 1ULL)),
+	EXOFS_MAX_ID	 = (EXOFS_MAX_INO_ID - 1 - EXOFS_OBJ_OFF),
+};
+
+/****************************************************************************
+ * Misc.
+ ****************************************************************************/
+#define EXOFS_BLKSHIFT	12
+#define EXOFS_BLKSIZE	(1UL << EXOFS_BLKSHIFT)
+
+/****************************************************************************
+ * superblock-related things
+ ****************************************************************************/
+#define EXOFS_SUPER_MAGIC	0x5DF5
+
+/*
+ * The file system control block - stored in object EXOFS_SUPER_ID's data.
+ * This is where the in-memory superblock is stored on disk.
+ */
+enum {EXOFS_FSCB_VER = 1, EXOFS_DT_VER = 1};
+struct exofs_fscb {
+	__le64  s_nextid;	/* Only used after mkfs */
+	__le64  s_numfiles;	/* Only used after mkfs */
+	__le32	s_version;	/* == EXOFS_FSCB_VER */
+	__le16  s_magic;	/* Magic signature */
+	__le16  s_newfs;	/* Non-zero if this is a new fs */
+
+	/* From here on it's a static part, only written by mkexofs */
+	__le64	s_dev_table_oid;   /* Resurved, not used */
+	__le64	s_dev_table_count; /* == 0 means no dev_table */
+} __packed;
+
+/*
+ * This struct is set on the FS partition's attributes.
+ * [EXOFS_APAGE_SB_DATA, EXOFS_ATTR_SB_STATS] and is written together
+ * with the create command, to atomically persist the sb writeable information.
+ */
+struct exofs_sb_stats {
+	__le64  s_nextid;	/* Highest object ID used */
+	__le64  s_numfiles;	/* Number of files on fs */
+} __packed;
+
+/*
+ * Describes the raid used in the FS. It is part of the device table.
+ * This here is taken from the pNFS-objects definition. In exofs we
+ * use one raid policy through-out the filesystem. (NOTE: the funny
+ * alignment at beginning. We take care of it at exofs_device_table.
+ */
+struct exofs_dt_data_map {
+	__le32	cb_num_comps;
+	__le64	cb_stripe_unit;
+	__le32	cb_group_width;
+	__le32	cb_group_depth;
+	__le32	cb_mirror_cnt;
+	__le32	cb_raid_algorithm;
+} __packed;
+
+/*
+ * This is an osd device information descriptor. It is a single entry in
+ * the exofs device table. It describes an osd target lun which
+ * contains data belonging to this FS. (Same partition_id on all devices)
+ */
+struct exofs_dt_device_info {
+	__le32	systemid_len;
+	u8	systemid[OSD_SYSTEMID_LEN];
+	__le64	long_name_offset;	/* If !0 then offset-in-file */
+	__le32	osdname_len;		/* */
+	u8	osdname[44];		/* Embbeded, Usually an asci uuid */
+} __packed;
+
+/*
+ * The EXOFS device table - stored in object EXOFS_DEVTABLE_ID's data.
+ * It contains the raid used for this multy-device FS and an array of
+ * participating devices.
+ */
+struct exofs_device_table {
+	__le32				dt_version;	/* == EXOFS_DT_VER */
+	struct exofs_dt_data_map	dt_data_map;	/* Raid policy to use */
+
+	/* Resurved space For future use. Total includeing this:
+	 * (8 * sizeof(le64))
+	 */
+	__le64				__Resurved[4];
+
+	__le64				dt_num_devices;	/* Array size */
+	struct exofs_dt_device_info	dt_dev_table[];	/* Array of devices */
+} __packed;
+
+/****************************************************************************
+ * inode-related things
+ ****************************************************************************/
+#define EXOFS_IDATA		5
+
+/*
+ * The file control block - stored in an object's attributes.  This is where
+ * the in-memory inode is stored on disk.
+ */
+struct exofs_fcb {
+	__le64  i_size;			/* Size of the file */
+	__le16  i_mode;         	/* File mode */
+	__le16  i_links_count;  	/* Links count */
+	__le32  i_uid;          	/* Owner Uid */
+	__le32  i_gid;          	/* Group Id */
+	__le32  i_atime;        	/* Access time */
+	__le32  i_ctime;        	/* Creation time */
+	__le32  i_mtime;        	/* Modification time */
+	__le32  i_flags;        	/* File flags (unused for now)*/
+	__le32  i_generation;   	/* File version (for NFS) */
+	__le32  i_data[EXOFS_IDATA];	/* Short symlink names and device #s */
+};
+
+#define EXOFS_INO_ATTR_SIZE	sizeof(struct exofs_fcb)
+
+/* This is the Attribute the fcb is stored in */
+static const struct __weak osd_attr g_attr_inode_data = ATTR_DEF(
+	EXOFS_APAGE_FS_DATA,
+	EXOFS_ATTR_INODE_DATA,
+	EXOFS_INO_ATTR_SIZE);
+
+/****************************************************************************
+ * dentry-related things
+ ****************************************************************************/
+#define EXOFS_NAME_LEN	255
+
+/*
+ * The on-disk directory entry
+ */
+struct exofs_dir_entry {
+	__le64		inode_no;		/* inode number           */
+	__le16		rec_len;		/* directory entry length */
+	u8		name_len;		/* name length            */
+	u8		file_type;		/* umm...file type        */
+	char		name[EXOFS_NAME_LEN];	/* file name              */
+};
+
+enum {
+	EXOFS_FT_UNKNOWN,
+	EXOFS_FT_REG_FILE,
+	EXOFS_FT_DIR,
+	EXOFS_FT_CHRDEV,
+	EXOFS_FT_BLKDEV,
+	EXOFS_FT_FIFO,
+	EXOFS_FT_SOCK,
+	EXOFS_FT_SYMLINK,
+	EXOFS_FT_MAX
+};
+
+#define EXOFS_DIR_PAD			4
+#define EXOFS_DIR_ROUND			(EXOFS_DIR_PAD - 1)
+#define EXOFS_DIR_REC_LEN(name_len) \
+	(((name_len) + offsetof(struct exofs_dir_entry, name)  + \
+	  EXOFS_DIR_ROUND) & ~EXOFS_DIR_ROUND)
+
+/*
+ * The on-disk (optional) layout structure.
+ * sits in an EXOFS_ATTR_INODE_FILE_LAYOUT or EXOFS_ATTR_INODE_DIR_LAYOUT
+ * attribute, attached to any inode, usually to a directory.
+ */
+
+enum exofs_inode_layout_gen_functions {
+	LAYOUT_MOVING_WINDOW = 0,
+	LAYOUT_IMPLICT = 1,
+};
+
+struct exofs_on_disk_inode_layout {
+	__le16 gen_func; /* One of enum exofs_inode_layout_gen_functions */
+	__le16 pad;
+	union {
+		/* gen_func == LAYOUT_MOVING_WINDOW (default) */
+		struct exofs_layout_sliding_window {
+			__le32 num_devices; /* first n devices in global-table*/
+		} sliding_window __packed;
+
+		/* gen_func == LAYOUT_IMPLICT */
+		struct exofs_layout_implict_list {
+			struct exofs_dt_data_map data_map;
+			/* Variable array of size data_map.cb_num_comps. These
+			 * are device indexes of the devices in the global table
+			 */
+			__le32 dev_indexes[];
+		} implict __packed;
+	};
+} __packed;
+
+static inline size_t exofs_on_disk_inode_layout_size(unsigned max_devs)
+{
+	return sizeof(struct exofs_on_disk_inode_layout) +
+		max_devs * sizeof(__le32);
+}
+
+#endif /*ifndef __EXOFS_COM_H__*/