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 56 struct 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 70 struct 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 */ 80 struct 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