1/*	$NetBSD: ebh.h,v 1.4 2016/08/06 20:42:29 dholland Exp $	*/
2
3/*-
4 * Copyright (c) 2010 Department of Software Engineering,
5 *		      University of Szeged, Hungary
6 * Copyright (c) 2010 David Tengeri <dtengeri@inf.u-szeged.hu>
7 * Copyright (c) 2010 Adam Hoka <ahoka@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#ifndef EBH_H_
36#define EBH_H_
37
38#ifdef _KERNEL
39#include <sys/param.h>
40#include <sys/kernel.h>
41#include <sys/cdefs.h>
42#include <sys/stdint.h>
43#include <sys/types.h>
44#include <sys/tree.h>
45#include <sys/queue.h>
46#include <sys/kmem.h>
47#include <sys/endian.h>
48#include <sys/rwlock.h>
49#include <sys/condvar.h>
50#include <sys/mutex.h>
51#include <sys/kthread.h>
52
53#include <dev/flash/flash.h>
54#include "debug.h"
55#include "ebh_misc.h"
56#endif /* _KERNEL */
57
58#include "ebh_media.h"
59
60/**
61 * struct  chfs_eb_hdr - in-memory representation of eraseblock headers
62 * @ec_hdr: erase counter header ob eraseblock
63 * @u.nor_hdr: eraseblock header on NOR flash
64 * @u.nand_hdr: eraseblock header on NAND flash
65 */
66struct  chfs_eb_hdr {
67	struct chfs_eb_ec_hdr ec_hdr;
68	union {
69		struct chfs_nor_eb_hdr  nor_hdr;
70		struct chfs_nand_eb_hdr nand_hdr;
71	} u;
72};
73
74#ifdef _KERNEL
75/* Maximum retries when getting new PEB before exit with failure */
76#define CHFS_MAX_GET_PEB_RETRIES 2
77
78/**
79 * LEB status
80 *
81 */
82enum {
83	EBH_LEB_UNMAPPED = -1,
84	EBH_LEB_MAPPED,
85	EBH_LEB_DIRTY,
86	EBH_LEB_INVALID,
87	EBH_LEB_ERASE,
88	EBH_LEB_ERASED,
89	EBH_LEB_FREE,
90};
91
92/**
93 * EB header status
94 */
95enum {
96	EBHDR_LEB_OK = 0,
97	EBHDR_LEB_DIRTY,
98	EBHDR_LEB_INVALIDATED,
99	EBHDR_LEB_BADMAGIC,
100	EBHDR_LEB_BADCRC,
101	EBHDR_LEB_FREE,
102	EBHDR_LEB_NO_HDR,
103};
104
105struct chfs_ebh;
106
107/**
108 * struct chfs_ltree_entry - an entry in the lock tree
109 * @rb: RB-node of the tree
110 * @lnr: logical eraseblock number
111 * @users: counts the tasks that are using or want to use the eraseblock
112 * @mutex: read/write mutex to lock the eraseblock
113 */
114struct chfs_ltree_entry {
115	RB_ENTRY(chfs_ltree_entry) rb;
116	int lnr;
117	int users;
118	krwlock_t mutex;
119};
120
121/* Generate structure for Lock tree's red-black tree */
122RB_HEAD(ltree_rbtree, chfs_ltree_entry);
123
124
125/**
126 * struct chfs_scan_leb - scanning infomration about a physical eraseblock
127 * @erase_cnt: erase counter
128 * @pebnr: physical eraseblock number
129 * @info: the status of the PEB's eraseblock header when NOR serial when NAND
130 * @u.list: link in one of the eraseblock list
131 * @u.rb: link in the used RB-tree of chfs_scan_info
132 */
133struct chfs_scan_leb {
134	int erase_cnt;
135	int pebnr;
136	int lnr;
137	uint64_t info;
138	union {
139		TAILQ_ENTRY(chfs_scan_leb) queue;
140		RB_ENTRY(chfs_scan_leb) rb;
141	} u;
142};
143
144TAILQ_HEAD(scan_leb_queue, chfs_scan_leb);
145RB_HEAD(scan_leb_used_rbtree, chfs_scan_leb);
146
147
148/**
149 * struct chfs_scan_info - chfs scanning information
150 * @corrupted: queue of corrupted physical eraseblocks
151 * @free: queue of free physical eraseblocks
152 * @erase: queue of the physical eraseblocks signed to erase
153 * @erased: queue of physical eraseblocks that contain no header
154 * @used: RB-tree of used PEBs describing by chfs_scan_leb
155 * @sum_of_ec: summary of erase counters
156 * @num_of_eb: number of free and used eraseblocks
157 * @bad_peb_cnt: counter of bad eraseblocks
158 *
159 * This structure contains information about the scanning for further
160 * processing.
161 */
162struct chfs_scan_info {
163	struct scan_leb_queue corrupted;
164	struct scan_leb_queue free;
165	struct scan_leb_queue erase;
166	struct scan_leb_queue erased;
167	struct scan_leb_used_rbtree used;
168	uint64_t sum_of_ec;
169	int num_of_eb;
170	int bad_peb_cnt;
171};
172
173/**
174 * struct chfs_peb - PEB information for erasing and wear leveling
175 * @erase_cnt: erase counter of the physical eraseblock
176 * @pebnr: physical eraseblock number
177 * @u.queue: link to the queue of the PEBs waiting for erase
178 * @u.rb: link to the RB-tree to the free PEBs
179 */
180struct chfs_peb {
181	int erase_cnt;
182	int pebnr;
183	union {
184		TAILQ_ENTRY(chfs_peb) queue;
185		RB_ENTRY(chfs_peb) rb;
186	} u;
187};
188
189/* Generate queue and rb-tree structures. */
190TAILQ_HEAD(peb_queue, chfs_peb);
191RB_HEAD(peb_free_rbtree, chfs_peb);
192RB_HEAD(peb_in_use_rbtree, chfs_peb);
193
194
195/*
196 * struct chfs_ebh_ops - collection of operations which
197 * 								 depends on flash type
198 * *************************************************************************** *
199 * Direct flash operations:
200 *
201 * @read_eb_hdr: read eraseblock header from media
202 * @write_eb_hdr: write eraseblock header to media
203 * @check_eb_hdr: validates eraseblock header
204 * @mark_eb_hdr_dirty_flash: marks eraseblock dirty on flash
205 * @invalidate_eb_hdr: invalidates eraseblock header
206 * @mark_eb_hdr_free: marks eraseblock header free (after erase)
207 * *************************************************************************** *
208 * Scanning operations:
209 *
210 * @process_eb: process an eraseblock information at scan
211 * *************************************************************************** *
212 * Misc operations:
213 *
214 * @create_eb_hdr: creates an eraseblock header based on flash type
215 * @calc_data_offs: calculates where the data starts
216 */
217struct chfs_ebh_ops {
218	int (*read_eb_hdr)(struct chfs_ebh *ebh, int pebnr,
219	    struct chfs_eb_hdr *ebhdr);
220	int (*write_eb_hdr)(struct chfs_ebh *ebh, int pebnr,
221	    struct chfs_eb_hdr *ebhdr);
222	int (*check_eb_hdr)(struct chfs_ebh *ebh, void *buf);
223	int (*mark_eb_hdr_dirty_flash)(struct chfs_ebh *ebh, int pebnr, int lid);
224	int (*invalidate_eb_hdr)(struct chfs_ebh *ebh, int pebnr);
225	int (*mark_eb_hdr_free)(struct chfs_ebh *ebh, int pebnr, int ec);
226
227	int (*process_eb)(struct chfs_ebh *ebh, struct chfs_scan_info *si,
228	    int pebnr, struct chfs_eb_hdr *ebhdr);
229
230	int (*create_eb_hdr)(struct chfs_eb_hdr *ebhdr, int lnr);
231	int (*calc_data_offs)(struct chfs_ebh *ebh, int pebnr, int offset);
232};
233
234/**
235 * struct erase_thread - background thread for erasing
236 * @thread: pointer to thread structure
237 * @wakeup: conditional variable for sleeping if there isn't any job to do
238 * @running: flag to signal a thread shutdown
239 */
240struct erase_thread {
241	lwp_t *eth_thread;
242	kcondvar_t eth_wakeup;
243	bool eth_running;
244};
245
246
247/**
248 * struct chfs_ebh - eraseblock handler descriptor
249 * @mtd: mtd device descriptor
250 * @eb_size: eraseblock size
251 * @peb_nr: number of PEBs
252 * @lmap: LEB to PEB mapping
253 * @layout_map: the LEBs layout (NOT USED YET)
254 * @ltree: the lock tree
255 * @ltree_lock: protects the tree
256 * @alc_mutex: serializes "atomic LEB change" operation
257 * @free: RB-tree of the free easeblocks
258 * @in_use: RB-tree of PEBs are in use
259 * @to_erase: list of the PEBs waiting for erase
260 * @fully_erased: list of PEBs that have been erased but don't have header
261 * @erase_lock: list and tree lock for fully_erased and to_erase lists and
262 *		for the free RB-tree
263 * @bg_erase: background thread for eraseing PEBs.
264 * @ops: collection of operations which depends on flash type
265 * @max_serial: max serial number of eraseblocks, only used on NAND
266 */
267struct chfs_ebh {
268	struct peb_free_rbtree free;
269	struct peb_in_use_rbtree in_use;
270	struct peb_queue to_erase;
271	struct peb_queue fully_erased;
272	struct erase_thread bg_erase;
273	device_t flash_dev;
274	const struct flash_interface *flash_if;
275	struct chfs_ebh_ops *ops;
276	uint64_t *max_serial;
277	int *lmap;
278	//int *layout_map;
279	struct ltree_rbtree ltree;
280	//struct mutex alc_mutex;
281	kmutex_t ltree_lock;
282	kmutex_t alc_mutex;
283	kmutex_t erase_lock;
284	size_t eb_size;
285	size_t peb_nr;
286	flash_size_t flash_size;
287};
288
289/**
290 * struct chfs_erase_info_priv - private information for erase
291 * @ebh: eraseblock handler
292 * @peb: physical eraseblock information
293 */
294struct chfs_erase_info_priv {
295	struct chfs_ebh *ebh;
296	struct chfs_peb *peb;
297};
298
299/* ebh.c */
300
301int ebh_open(struct chfs_ebh *ebh, dev_t dev);
302int ebh_close(struct chfs_ebh *ebh);
303int ebh_read_leb(struct chfs_ebh *ebh, int lnr, char *buf,
304    uint32_t offset, size_t len, size_t *retlen);
305int ebh_write_leb(struct chfs_ebh *ebh, int lnr, char *buf,
306    uint32_t offset, size_t len, size_t *retlen);
307int ebh_erase_leb(struct chfs_ebh *ebh, int lnr);
308int ebh_map_leb(struct chfs_ebh *ebh, int lnr);
309int ebh_unmap_leb(struct chfs_ebh *ebh, int lnr);
310int ebh_is_mapped(struct chfs_ebh *ebh, int lnr);
311int ebh_change_leb(struct chfs_ebh *ebh, int lnr, char *buf,
312    size_t len, size_t *retlen);
313
314#endif /* _KERNEL */
315
316#endif /* EBH_H_ */
317