1/*
2 * CXL Flash Device Driver
3 *
4 * Written by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>, IBM Corporation
5 *             Matthew R. Ochs <mrochs@linux.vnet.ibm.com>, IBM Corporation
6 *
7 * Copyright (C) 2015 IBM Corporation
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 */
14
15#ifndef _CXLFLASH_VLUN_H
16#define _CXLFLASH_VLUN_H
17
18/* RHT - Resource Handle Table */
19#define MC_RHT_NMASK      16	/* in bits */
20#define MC_CHUNK_SHIFT    MC_RHT_NMASK	/* shift to go from LBA to chunk# */
21
22#define HIBIT             (BITS_PER_LONG - 1)
23
24#define MAX_AUN_CLONE_CNT 0xFF
25
26/*
27 * LXT - LBA Translation Table
28 *
29 * +-------+-------+-------+-------+-------+-------+-------+---+---+
30 * | RLBA_BASE                                     |LUN_IDX| P |SEL|
31 * +-------+-------+-------+-------+-------+-------+-------+---+---+
32 *
33 * The LXT Entry contains the physical LBA where the chunk starts (RLBA_BASE).
34 * AFU ORes the low order bits from the virtual LBA (offset into the chunk)
35 * with RLBA_BASE. The result is the physical LBA to be sent to storage.
36 * The LXT Entry also contains an index to a LUN TBL and a bitmask of which
37 * outgoing (FC) * ports can be selected. The port select bit-mask is ANDed
38 * with a global port select bit-mask maintained by the driver.
39 * In addition, it has permission bits that are ANDed with the
40 * RHT permissions to arrive at the final permissions for the chunk.
41 *
42 * LXT tables are allocated dynamically in groups. This is done to avoid
43 * a malloc/free overhead each time the LXT has to grow or shrink.
44 *
45 * Based on the current lxt_cnt (used), it is always possible to know
46 * how many are allocated (used+free). The number of allocated entries is
47 * not stored anywhere.
48 *
49 * The LXT table is re-allocated whenever it needs to cross into another group.
50*/
51#define LXT_GROUP_SIZE          8
52#define LXT_NUM_GROUPS(lxt_cnt) (((lxt_cnt) + 7)/8)	/* alloc'ed groups */
53#define LXT_LUNIDX_SHIFT  8	/* LXT entry, shift for LUN index */
54#define LXT_PERM_SHIFT    4	/* LXT entry, shift for permission bits */
55
56struct ba_lun_info {
57	u64 *lun_alloc_map;
58	u32 lun_bmap_size;
59	u32 total_aus;
60	u64 free_aun_cnt;
61
62	/* indices to be used for elevator lookup of free map */
63	u32 free_low_idx;
64	u32 free_curr_idx;
65	u32 free_high_idx;
66
67	u8 *aun_clone_map;
68};
69
70struct ba_lun {
71	u64 lun_id;
72	u64 wwpn;
73	size_t lsize;		/* LUN size in number of LBAs             */
74	size_t lba_size;	/* LBA size in number of bytes            */
75	size_t au_size;		/* Allocation Unit size in number of LBAs */
76	struct ba_lun_info *ba_lun_handle;
77};
78
79/* Block Allocator */
80struct blka {
81	struct ba_lun ba_lun;
82	u64 nchunk;		/* number of chunks */
83	struct mutex mutex;
84};
85
86#endif /* ifndef _CXLFLASH_SUPERPIPE_H */
87