Home | History | Annotate | Line # | Download | only in chfs
ebh.h revision 1.1
      1 /*	$NetBSD: ebh.h,v 1.1 2011/11/24 15:51:32 ahoka Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2010 Department of Software Engineering,
      5  *		      University of Szeged, Hungary
      6  * Copyright (c) 2010 David Tengeri <dtengeri (at) inf.u-szeged.hu>
      7  * Copyright (c) 2010 Adam Hoka <ahoka (at) NetBSD.org>
      8  * All rights reserved.
      9  *
     10  * This code is derived from software contributed to The NetBSD Foundation
     11  * by the Department of Software Engineering, University of Szeged, Hungary
     12  *
     13  * Redistribution and use in source and binary forms, with or without
     14  * modification, are permitted provided that the following conditions
     15  * are met:
     16  * 1. Redistributions of source code must retain the above copyright
     17  *    notice, this list of conditions and the following disclaimer.
     18  * 2. Redistributions in binary form must reproduce the above copyright
     19  *    notice, this list of conditions and the following disclaimer in the
     20  *    documentation and/or other materials provided with the distribution.
     21  *
     22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
     27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
     29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
     30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     32  * SUCH DAMAGE.
     33  */
     34 
     35 /*
     36  * ebh.h
     37  *
     38  *  Created on: 2009.11.03.
     39  *      Author: dtengeri
     40  */
     41 
     42 #ifndef EBH_H_
     43 #define EBH_H_
     44 
     45 #include <sys/param.h>
     46 #include <sys/kernel.h>
     47 #include <sys/cdefs.h>
     48 #include <sys/stdint.h>
     49 #include <sys/types.h>
     50 #include <sys/tree.h>
     51 #include <sys/queue.h>
     52 #include <sys/kmem.h>
     53 #include <sys/endian.h>
     54 #include <sys/rwlock.h>
     55 #include <sys/condvar.h>
     56 #include <sys/mutex.h>
     57 #include <sys/kthread.h>
     58 
     59 #include <dev/flash/flash.h>
     60 #include <ufs/chfs/ebh_media.h>
     61 #include <ufs/chfs/debug.h>
     62 #include <ufs/chfs/ebh_misc.h>
     63 
     64 /* Maximum retries when getting new PEB before exit with failure */
     65 #define CHFS_MAX_GET_PEB_RETRIES 2
     66 
     67 /**
     68  * LEB status
     69  *
     70  */
     71 enum {
     72 	EBH_LEB_UNMAPPED = -1,
     73 	EBH_LEB_MAPPED,
     74 	EBH_LEB_DIRTY,
     75 	EBH_LEB_INVALID,
     76 	EBH_LEB_ERASE,
     77 	EBH_LEB_ERASED,
     78 	EBH_LEB_FREE,
     79 };
     80 
     81 /**
     82  * EB header status
     83  */
     84 enum {
     85 	EBHDR_LEB_OK = 0,
     86 	EBHDR_LEB_DIRTY,
     87 	EBHDR_LEB_INVALIDATED,
     88 	EBHDR_LEB_BADMAGIC,
     89 	EBHDR_LEB_BADCRC,
     90 	EBHDR_LEB_FREE,
     91 	EBHDR_LEB_NO_HDR,
     92 };
     93 
     94 struct chfs_ebh;
     95 
     96 /**
     97  * struct chfs_ltree_entry - an netry in the lock tree
     98  * @rb: RB-node of the tree
     99  * @lnr: logical eraseblock number
    100  * @users: counts the tasks that are using or want to use the eraseblock
    101  * @mutex: read/write mutex to lock the eraseblock
    102  */
    103 struct chfs_ltree_entry {
    104 	RB_ENTRY(chfs_ltree_entry) rb;
    105 	int lnr;
    106 	int users;
    107 	krwlock_t mutex;
    108 };
    109 
    110 /* Generate structure for Lock tree's red-black tree */
    111 RB_HEAD(ltree_rbtree, chfs_ltree_entry);
    112 
    113 
    114 /**
    115  * struct chfs_scan_leb - scanning infomration about a physical eraseblock
    116  * @erase_cnt: erase counter
    117  * @pebnr: physical eraseblock number
    118  * @info: the status of the PEB's eraseblock header when NOR serial when NAND
    119  * @u.list: link in one of the eraseblock list
    120  * @u.rb: link in the used RB-tree of chfs_scan_info
    121  */
    122 struct chfs_scan_leb {
    123 	int erase_cnt;
    124 	int pebnr;
    125 	int lnr;
    126 	uint64_t info;
    127 	union {
    128 		TAILQ_ENTRY(chfs_scan_leb) queue;
    129 		RB_ENTRY(chfs_scan_leb) rb;
    130 	} u;
    131 };
    132 
    133 TAILQ_HEAD(scan_leb_queue, chfs_scan_leb);
    134 RB_HEAD(scan_leb_used_rbtree, chfs_scan_leb);
    135 
    136 
    137 
    138 /**
    139  * struct chfs_scan_info - chfs scanning information
    140  * @corrupted: queue of corrupted physical eraseblocks
    141  * @free: queue of free physical eraseblocks
    142  * @erase: queue of the physical eraseblocks signed to erase
    143  * @erased: queue of physical eraseblocks that contain no header
    144  * @used: RB-tree of used PEBs describing by chfs_scan_leb
    145  * @sum_of_ec: summary of erase counters
    146  * @num_of_eb: number of free and used eraseblocks
    147  * @bad_peb_cnt: counter of bad eraseblocks
    148  *
    149  * This structure contains information about the scanning for further
    150  * processing.
    151  */
    152 struct chfs_scan_info {
    153 	struct scan_leb_queue corrupted;
    154 	struct scan_leb_queue free;
    155 	struct scan_leb_queue erase;
    156 	struct scan_leb_queue erased;
    157 	struct scan_leb_used_rbtree used;
    158 	uint64_t sum_of_ec;
    159 	int num_of_eb;
    160 	int bad_peb_cnt;
    161 };
    162 
    163 /**
    164  * struct chfs_peb - PEB information for erasing and wear leveling
    165  * @erase_cnt: erase counter of the physical eraseblock
    166  * @pebnr: physical eraseblock number
    167  * @u.queue: link to the queue of the PEBs waiting for erase
    168  * @u.rb: link to the RB-tree to the free PEBs
    169  */
    170 struct chfs_peb {
    171 	int erase_cnt;
    172 	int pebnr;
    173 	union {
    174 		TAILQ_ENTRY(chfs_peb) queue;
    175 		RB_ENTRY(chfs_peb) rb;
    176 	} u;
    177 };
    178 
    179 /* Generate queue and rb-tree structures. */
    180 TAILQ_HEAD(peb_queue, chfs_peb);
    181 RB_HEAD(peb_free_rbtree, chfs_peb);
    182 RB_HEAD(peb_in_use_rbtree, chfs_peb);
    183 
    184 /**
    185  * struct  chfs_eb_hdr - in-memory representation of eraseblock headers
    186  * @ec_hdr: erase counter header ob eraseblock
    187  * @u.nor_hdr: eraseblock header on NOR flash
    188  * @u.nand_hdr: eraseblock header on NAND flash
    189  */
    190 struct  chfs_eb_hdr {
    191 	struct chfs_eb_ec_hdr ec_hdr;
    192 	union {
    193 		struct chfs_nor_eb_hdr  nor_hdr;
    194 		struct chfs_nand_eb_hdr nand_hdr;
    195 	} u;
    196 };
    197 
    198 /*
    199  * struct chfs_ebh_ops - collection of operations which
    200  * 								 depends on flash type
    201  * *************************************************************************** *
    202  * Direct flash operations:
    203  *
    204  * @read_eb_hdr: read eraseblock header from media
    205  * @write_eb_hdr: write eraseblock header to media
    206  * @check_eb_hdr: validates eraseblock header
    207  * @mark_eb_hdr_dirty_flash: marks eraseblock dirty on flash
    208  * @invalidate_eb_hdr: invalidates eraseblock header
    209  * @mark_eb_hdr_free: marks eraseblock header free (after erase)
    210  * *************************************************************************** *
    211  * Scanning operations:
    212  *
    213  * @process_eb: process an eraseblock information at scan
    214  * *************************************************************************** *
    215  * Misc operations:
    216  *
    217  * @create_eb_hdr: creates an eraseblock header based on flash type
    218  * @calc_data_offs: calculates where the data starts
    219  */
    220 struct chfs_ebh_ops {
    221 	int (*read_eb_hdr)(struct chfs_ebh *ebh, int pebnr,
    222 	    struct chfs_eb_hdr *ebhdr);
    223 	int (*write_eb_hdr)(struct chfs_ebh *ebh, int pebnr,
    224 	    struct chfs_eb_hdr *ebhdr);
    225 	int (*check_eb_hdr)(struct chfs_ebh *ebh, void *buf);
    226 	int (*mark_eb_hdr_dirty_flash)(struct chfs_ebh *ebh, int pebnr, int lid);
    227 	int (*invalidate_eb_hdr)(struct chfs_ebh *ebh, int pebnr);
    228 	int (*mark_eb_hdr_free)(struct chfs_ebh *ebh, int pebnr, int ec);
    229 
    230 	int (*process_eb)(struct chfs_ebh *ebh, struct chfs_scan_info *si,
    231 	    int pebnr, struct chfs_eb_hdr *ebhdr);
    232 
    233 	int (*create_eb_hdr)(struct chfs_eb_hdr *ebhdr, int lnr);
    234 	int (*calc_data_offs)(struct chfs_ebh *ebh, int pebnr, int offset);
    235 };
    236 
    237 /**
    238  * struct erase_thread - background thread for erasing
    239  * @thread: pointer to thread structure
    240  * @wakeup: conditional variable for sleeping if there isn't any job to do
    241  * @running: flag to signal a thread shutdown
    242  */
    243 struct erase_thread {
    244 	lwp_t *eth_thread;
    245 	kcondvar_t eth_wakeup;
    246 	bool eth_running;
    247 };
    248 
    249 
    250 /**
    251  * struct chfs_ebh - eraseblock handler descriptor
    252  * @mtd: mtd device descriptor
    253  * @eb_size: eraseblock size
    254  * @peb_nr: number of PEBs
    255  * @lmap: LEB to PEB mapping
    256  * @layout_map: the LEBs layout (NOT USED YET)
    257  * @ltree: the lock tree
    258  * @ltree_lock: protects the tree
    259  * @alc_mutex: serializes "atomic LEB change" operation
    260  * @free: RB-tree of the free easeblocks
    261  * @in_use: RB-tree of PEBs are in use
    262  * @to_erase: list of the PEBs waiting for erase
    263  * @fully_erased: list of PEBs that have been erased but don't have header
    264  * @erase_lock: list and tree lock for fully_erased and to_erase lists and
    265  *		for the free RB-tree
    266  * @bg_erase: background thread for eraseing PEBs.
    267  * @ops: collection of operations which depends on flash type
    268  * @max_serial: max serial number of eraseblocks, only used on NAND
    269  */
    270 struct chfs_ebh {
    271 	struct peb_free_rbtree free;
    272 	struct peb_in_use_rbtree in_use;
    273 	struct peb_queue to_erase;
    274 	struct peb_queue fully_erased;
    275 	struct erase_thread bg_erase;
    276 	device_t flash_dev;
    277 	const struct flash_interface *flash_if;
    278 	struct chfs_ebh_ops *ops;
    279 	uint64_t *max_serial;
    280 	int *lmap;
    281 	//int *layout_map;
    282 	struct ltree_rbtree ltree;
    283 	//struct mutex alc_mutex;
    284 	kmutex_t ltree_lock;
    285 	kmutex_t alc_mutex;
    286 	kmutex_t erase_lock;
    287 	size_t eb_size;
    288 	size_t peb_nr;
    289 	flash_size_t flash_size;
    290 };
    291 
    292 /**
    293  * struct chfs_erase_info_priv - private information for erase
    294  * @ebh: eraseblock handler
    295  * @peb: physical eraseblock information
    296  */
    297 struct chfs_erase_info_priv {
    298 	struct chfs_ebh *ebh;
    299 	struct chfs_peb *peb;
    300 };
    301 
    302 /* ebh.c */
    303 
    304 int ebh_open(struct chfs_ebh *ebh, dev_t dev);
    305 int ebh_close(struct chfs_ebh *ebh);
    306 int ebh_read_leb(struct chfs_ebh *ebh, int lnr, char *buf,
    307     uint32_t offset, size_t len, size_t *retlen);
    308 int ebh_write_leb(struct chfs_ebh *ebh, int lnr, char *buf,
    309     uint32_t offset, size_t len, size_t *retlen);
    310 int ebh_erase_leb(struct chfs_ebh *ebh, int lnr);
    311 int ebh_map_leb(struct chfs_ebh *ebh, int lnr);
    312 int ebh_unmap_leb(struct chfs_ebh *ebh, int lnr);
    313 int ebh_is_mapped(struct chfs_ebh *ebh, int lnr);
    314 int ebh_change_leb(struct chfs_ebh *ebh, int lnr, char *buf,
    315     size_t len, size_t *retlen);
    316 
    317 
    318 #endif /* EBH_H_ */
    319