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-rw-r--r--fs/afs/xdr_fs.h116
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diff --git a/fs/afs/xdr_fs.h b/fs/afs/xdr_fs.h
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+++ b/fs/afs/xdr_fs.h
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+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* AFS fileserver XDR types
+ *
+ * Copyright (C) 2018 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#ifndef XDR_FS_H
+#define XDR_FS_H
+
+struct afs_xdr_AFSFetchStatus {
+ __be32 if_version;
+#define AFS_FSTATUS_VERSION 1
+ __be32 type;
+ __be32 nlink;
+ __be32 size_lo;
+ __be32 data_version_lo;
+ __be32 author;
+ __be32 owner;
+ __be32 caller_access;
+ __be32 anon_access;
+ __be32 mode;
+ __be32 parent_vnode;
+ __be32 parent_unique;
+ __be32 seg_size;
+ __be32 mtime_client;
+ __be32 mtime_server;
+ __be32 group;
+ __be32 sync_counter;
+ __be32 data_version_hi;
+ __be32 lock_count;
+ __be32 size_hi;
+ __be32 abort_code;
+} __packed;
+
+#define AFS_DIR_HASHTBL_SIZE 128
+#define AFS_DIR_DIRENT_SIZE 32
+#define AFS_DIR_SLOTS_PER_BLOCK 64
+#define AFS_DIR_BLOCK_SIZE 2048
+#define AFS_DIR_BLOCKS_PER_PAGE (PAGE_SIZE / AFS_DIR_BLOCK_SIZE)
+#define AFS_DIR_MAX_SLOTS 65536
+#define AFS_DIR_BLOCKS_WITH_CTR 128
+#define AFS_DIR_MAX_BLOCKS 1023
+#define AFS_DIR_RESV_BLOCKS 1
+#define AFS_DIR_RESV_BLOCKS0 13
+
+/*
+ * Directory entry structure.
+ */
+union afs_xdr_dirent {
+ struct {
+ u8 valid;
+ u8 unused[1];
+ __be16 hash_next;
+ __be32 vnode;
+ __be32 unique;
+ u8 name[];
+ /* When determining the number of dirent slots needed to
+ * represent a directory entry, name should be assumed to be 16
+ * bytes, due to a now-standardised (mis)calculation, but it is
+ * in fact 20 bytes in size. afs_dir_calc_slots() should be
+ * used for this.
+ *
+ * For names longer than (16 or) 20 bytes, extra slots should
+ * be annexed to this one using the extended_name format.
+ */
+ } u;
+ u8 extended_name[32];
+} __packed;
+
+/*
+ * Directory block header (one at the beginning of every 2048-byte block).
+ */
+struct afs_xdr_dir_hdr {
+ __be16 npages;
+ __be16 magic;
+#define AFS_DIR_MAGIC htons(1234)
+ u8 reserved;
+ u8 bitmap[8];
+ u8 pad[19];
+} __packed;
+
+/*
+ * Directory block layout
+ */
+union afs_xdr_dir_block {
+ struct afs_xdr_dir_hdr hdr;
+
+ struct {
+ struct afs_xdr_dir_hdr hdr;
+ u8 alloc_ctrs[AFS_DIR_MAX_BLOCKS];
+ __be16 hashtable[AFS_DIR_HASHTBL_SIZE];
+ } meta;
+
+ union afs_xdr_dirent dirents[AFS_DIR_SLOTS_PER_BLOCK];
+} __packed;
+
+/*
+ * Directory layout on a linux VM page.
+ */
+struct afs_xdr_dir_page {
+ union afs_xdr_dir_block blocks[AFS_DIR_BLOCKS_PER_PAGE];
+};
+
+/*
+ * Calculate the number of dirent slots required for any given name length.
+ * The calculation is made assuming the part of the name in the first slot is
+ * 16 bytes, rather than 20, but this miscalculation is now standardised.
+ */
+static inline unsigned int afs_dir_calc_slots(size_t name_len)
+{
+ name_len++; /* NUL-terminated */
+ return 1 + ((name_len + 15) / AFS_DIR_DIRENT_SIZE);
+}
+
+#endif /* XDR_FS_H */