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-rw-r--r--include/zfs/zap_impl.h111
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diff --git a/include/zfs/zap_impl.h b/include/zfs/zap_impl.h
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+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc.
+ *
+ * This program 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+/*
+ * Copyright (c) 2008, 2011, Oracle and/or its affiliates. All rights reserved.
+ */
+
+#ifndef _SYS_ZAP_IMPL_H
+#define _SYS_ZAP_IMPL_H
+
+#define ZAP_MAGIC 0x2F52AB2ABULL
+
+#define ZAP_HASHBITS 28
+#define MZAP_ENT_LEN 64
+#define MZAP_NAME_LEN (MZAP_ENT_LEN - 8 - 4 - 2)
+#define MZAP_MAX_BLKSHIFT SPA_MAXBLOCKSHIFT
+#define MZAP_MAX_BLKSZ (1 << MZAP_MAX_BLKSHIFT)
+
+typedef struct mzap_ent_phys {
+ uint64_t mze_value;
+ uint32_t mze_cd;
+ uint16_t mze_pad; /* in case we want to chain them someday */
+ char mze_name[MZAP_NAME_LEN];
+} mzap_ent_phys_t;
+
+typedef struct mzap_phys {
+ uint64_t mz_block_type; /* ZBT_MICRO */
+ uint64_t mz_salt;
+ uint64_t mz_pad[6];
+ mzap_ent_phys_t mz_chunk[1];
+ /* actually variable size depending on block size */
+} mzap_phys_t;
+
+/*
+ * The (fat) zap is stored in one object. It is an array of
+ * 1<<FZAP_BLOCK_SHIFT byte blocks. The layout looks like one of:
+ *
+ * ptrtbl fits in first block:
+ * [zap_phys_t zap_ptrtbl_shift < 6] [zap_leaf_t] ...
+ *
+ * ptrtbl too big for first block:
+ * [zap_phys_t zap_ptrtbl_shift >= 6] [zap_leaf_t] [ptrtbl] ...
+ *
+ */
+
+#define ZBT_LEAF ((1ULL << 63) + 0)
+#define ZBT_HEADER ((1ULL << 63) + 1)
+#define ZBT_MICRO ((1ULL << 63) + 3)
+/* any other values are ptrtbl blocks */
+
+/*
+ * the embedded pointer table takes up half a block:
+ * block size / entry size (2^3) / 2
+ */
+#define ZAP_EMBEDDED_PTRTBL_SHIFT(zap) (FZAP_BLOCK_SHIFT(zap) - 3 - 1)
+
+/*
+ * The embedded pointer table starts half-way through the block. Since
+ * the pointer table itself is half the block, it starts at (64-bit)
+ * word number (1<<ZAP_EMBEDDED_PTRTBL_SHIFT(zap)).
+ */
+#define ZAP_EMBEDDED_PTRTBL_ENT(zap, idx) \
+ ((uint64_t *)(zap)->zap_f.zap_phys) \
+ [(idx) + (1<<ZAP_EMBEDDED_PTRTBL_SHIFT(zap))]
+
+/*
+ * TAKE NOTE:
+ * If zap_phys_t is modified, zap_byteswap() must be modified.
+ */
+typedef struct zap_phys {
+ uint64_t zap_block_type; /* ZBT_HEADER */
+ uint64_t zap_magic; /* ZAP_MAGIC */
+
+ struct zap_table_phys {
+ uint64_t zt_blk; /* starting block number */
+ uint64_t zt_numblks; /* number of blocks */
+ uint64_t zt_shift; /* bits to index it */
+ uint64_t zt_nextblk; /* next (larger) copy start block */
+ uint64_t zt_blks_copied; /* number source blocks copied */
+ } zap_ptrtbl;
+
+ uint64_t zap_freeblk; /* the next free block */
+ uint64_t zap_num_leafs; /* number of leafs */
+ uint64_t zap_num_entries; /* number of entries */
+ uint64_t zap_salt; /* salt to stir into hash function */
+ uint64_t zap_normflags; /* flags for u8_textprep_str() */
+ uint64_t zap_flags; /* zap_flag_t */
+ /*
+ * This structure is followed by padding, and then the embedded
+ * pointer table. The embedded pointer table takes up second
+ * half of the block. It is accessed using the
+ * ZAP_EMBEDDED_PTRTBL_ENT() macro.
+ */
+} zap_phys_t;
+
+#endif /* _SYS_ZAP_IMPL_H */