xref: /linux/fs/jffs2/nodelist.h (revision 9ce7677cfd7cd871adb457c80bea3b581b839641)
1 /*
2  * JFFS2 -- Journalling Flash File System, Version 2.
3  *
4  * Copyright (C) 2001-2003 Red Hat, Inc.
5  *
6  * Created by David Woodhouse <dwmw2@infradead.org>
7  *
8  * For licensing information, see the file 'LICENCE' in this directory.
9  *
10  * $Id: nodelist.h,v 1.140 2005/09/07 08:34:54 havasi Exp $
11  *
12  */
13 
14 #ifndef __JFFS2_NODELIST_H__
15 #define __JFFS2_NODELIST_H__
16 
17 #include <linux/config.h>
18 #include <linux/fs.h>
19 #include <linux/types.h>
20 #include <linux/jffs2.h>
21 #include <linux/jffs2_fs_sb.h>
22 #include <linux/jffs2_fs_i.h>
23 #include "summary.h"
24 
25 #ifdef __ECOS
26 #include "os-ecos.h"
27 #else
28 #include <linux/mtd/compatmac.h> /* For compatibility with older kernels */
29 #include "os-linux.h"
30 #endif
31 
32 #define JFFS2_NATIVE_ENDIAN
33 
34 /* Note we handle mode bits conversion from JFFS2 (i.e. Linux) to/from
35    whatever OS we're actually running on here too. */
36 
37 #if defined(JFFS2_NATIVE_ENDIAN)
38 #define cpu_to_je16(x) ((jint16_t){x})
39 #define cpu_to_je32(x) ((jint32_t){x})
40 #define cpu_to_jemode(x) ((jmode_t){os_to_jffs2_mode(x)})
41 
42 #define je16_to_cpu(x) ((x).v16)
43 #define je32_to_cpu(x) ((x).v32)
44 #define jemode_to_cpu(x) (jffs2_to_os_mode((x).m))
45 #elif defined(JFFS2_BIG_ENDIAN)
46 #define cpu_to_je16(x) ((jint16_t){cpu_to_be16(x)})
47 #define cpu_to_je32(x) ((jint32_t){cpu_to_be32(x)})
48 #define cpu_to_jemode(x) ((jmode_t){cpu_to_be32(os_to_jffs2_mode(x))})
49 
50 #define je16_to_cpu(x) (be16_to_cpu(x.v16))
51 #define je32_to_cpu(x) (be32_to_cpu(x.v32))
52 #define jemode_to_cpu(x) (be32_to_cpu(jffs2_to_os_mode((x).m)))
53 #elif defined(JFFS2_LITTLE_ENDIAN)
54 #define cpu_to_je16(x) ((jint16_t){cpu_to_le16(x)})
55 #define cpu_to_je32(x) ((jint32_t){cpu_to_le32(x)})
56 #define cpu_to_jemode(x) ((jmode_t){cpu_to_le32(os_to_jffs2_mode(x))})
57 
58 #define je16_to_cpu(x) (le16_to_cpu(x.v16))
59 #define je32_to_cpu(x) (le32_to_cpu(x.v32))
60 #define jemode_to_cpu(x) (le32_to_cpu(jffs2_to_os_mode((x).m)))
61 #else
62 #error wibble
63 #endif
64 
65 /* The minimal node header size */
66 #define JFFS2_MIN_NODE_HEADER sizeof(struct jffs2_raw_dirent)
67 
68 /*
69   This is all we need to keep in-core for each raw node during normal
70   operation. As and when we do read_inode on a particular inode, we can
71   scan the nodes which are listed for it and build up a proper map of
72   which nodes are currently valid. JFFSv1 always used to keep that whole
73   map in core for each inode.
74 */
75 struct jffs2_raw_node_ref
76 {
77 	struct jffs2_raw_node_ref *next_in_ino; /* Points to the next raw_node_ref
78 		for this inode. If this is the last, it points to the inode_cache
79 		for this inode instead. The inode_cache will have NULL in the first
80 		word so you know when you've got there :) */
81 	struct jffs2_raw_node_ref *next_phys;
82 	uint32_t flash_offset;
83 	uint32_t __totlen; /* This may die; use ref_totlen(c, jeb, ) below */
84 };
85 
86         /* flash_offset & 3 always has to be zero, because nodes are
87 	   always aligned at 4 bytes. So we have a couple of extra bits
88 	   to play with, which indicate the node's status; see below: */
89 #define REF_UNCHECKED	0	/* We haven't yet checked the CRC or built its inode */
90 #define REF_OBSOLETE	1	/* Obsolete, can be completely ignored */
91 #define REF_PRISTINE	2	/* Completely clean. GC without looking */
92 #define REF_NORMAL	3	/* Possibly overlapped. Read the page and write again on GC */
93 #define ref_flags(ref)		((ref)->flash_offset & 3)
94 #define ref_offset(ref)		((ref)->flash_offset & ~3)
95 #define ref_obsolete(ref)	(((ref)->flash_offset & 3) == REF_OBSOLETE)
96 #define mark_ref_normal(ref)    do { (ref)->flash_offset = ref_offset(ref) | REF_NORMAL; } while(0)
97 
98 /* For each inode in the filesystem, we need to keep a record of
99    nlink, because it would be a PITA to scan the whole directory tree
100    at read_inode() time to calculate it, and to keep sufficient information
101    in the raw_node_ref (basically both parent and child inode number for
102    dirent nodes) would take more space than this does. We also keep
103    a pointer to the first physical node which is part of this inode, too.
104 */
105 struct jffs2_inode_cache {
106 	struct jffs2_full_dirent *scan_dents; /* Used during scan to hold
107 		temporary lists of dirents, and later must be set to
108 		NULL to mark the end of the raw_node_ref->next_in_ino
109 		chain. */
110 	struct jffs2_inode_cache *next;
111 	struct jffs2_raw_node_ref *nodes;
112 	uint32_t ino;
113 	int nlink;
114 	int state;
115 };
116 
117 /* Inode states for 'state' above. We need the 'GC' state to prevent
118    someone from doing a read_inode() while we're moving a 'REF_PRISTINE'
119    node without going through all the iget() nonsense */
120 #define INO_STATE_UNCHECKED	0	/* CRC checks not yet done */
121 #define INO_STATE_CHECKING	1	/* CRC checks in progress */
122 #define INO_STATE_PRESENT	2	/* In core */
123 #define INO_STATE_CHECKEDABSENT	3	/* Checked, cleared again */
124 #define INO_STATE_GC		4	/* GCing a 'pristine' node */
125 #define INO_STATE_READING	5	/* In read_inode() */
126 #define INO_STATE_CLEARING	6	/* In clear_inode() */
127 
128 #define INOCACHE_HASHSIZE 128
129 
130 /*
131   Larger representation of a raw node, kept in-core only when the
132   struct inode for this particular ino is instantiated.
133 */
134 
135 struct jffs2_full_dnode
136 {
137 	struct jffs2_raw_node_ref *raw;
138 	uint32_t ofs; /* The offset to which the data of this node belongs */
139 	uint32_t size;
140 	uint32_t frags; /* Number of fragments which currently refer
141 			to this node. When this reaches zero,
142 			the node is obsolete.  */
143 };
144 
145 /*
146    Even larger representation of a raw node, kept in-core only while
147    we're actually building up the original map of which nodes go where,
148    in read_inode()
149 */
150 struct jffs2_tmp_dnode_info
151 {
152 	struct rb_node rb;
153 	struct jffs2_full_dnode *fn;
154 	uint32_t version;
155 	uint32_t data_crc;
156 	uint32_t partial_crc;
157 	uint32_t csize;
158 };
159 
160 struct jffs2_full_dirent
161 {
162 	struct jffs2_raw_node_ref *raw;
163 	struct jffs2_full_dirent *next;
164 	uint32_t version;
165 	uint32_t ino; /* == zero for unlink */
166 	unsigned int nhash;
167 	unsigned char type;
168 	unsigned char name[0];
169 };
170 
171 /*
172   Fragments - used to build a map of which raw node to obtain
173   data from for each part of the ino
174 */
175 struct jffs2_node_frag
176 {
177 	struct rb_node rb;
178 	struct jffs2_full_dnode *node; /* NULL for holes */
179 	uint32_t size;
180 	uint32_t ofs; /* The offset to which this fragment belongs */
181 };
182 
183 struct jffs2_eraseblock
184 {
185 	struct list_head list;
186 	int bad_count;
187 	uint32_t offset;		/* of this block in the MTD */
188 
189 	uint32_t unchecked_size;
190 	uint32_t used_size;
191 	uint32_t dirty_size;
192 	uint32_t wasted_size;
193 	uint32_t free_size;	/* Note that sector_size - free_size
194 				   is the address of the first free space */
195 	struct jffs2_raw_node_ref *first_node;
196 	struct jffs2_raw_node_ref *last_node;
197 
198 	struct jffs2_raw_node_ref *gc_node;	/* Next node to be garbage collected */
199 };
200 
201 static inline int jffs2_blocks_use_vmalloc(struct jffs2_sb_info *c)
202 {
203 	return ((c->flash_size / c->sector_size) * sizeof (struct jffs2_eraseblock)) > (128 * 1024);
204 }
205 
206 /* Calculate totlen from surrounding nodes or eraseblock */
207 static inline uint32_t __ref_totlen(struct jffs2_sb_info *c,
208 				    struct jffs2_eraseblock *jeb,
209 				    struct jffs2_raw_node_ref *ref)
210 {
211 	uint32_t ref_end;
212 
213 	if (ref->next_phys)
214 		ref_end = ref_offset(ref->next_phys);
215 	else {
216 		if (!jeb)
217 			jeb = &c->blocks[ref->flash_offset / c->sector_size];
218 
219 		/* Last node in block. Use free_space */
220 		BUG_ON(ref != jeb->last_node);
221 		ref_end = jeb->offset + c->sector_size - jeb->free_size;
222 	}
223 	return ref_end - ref_offset(ref);
224 }
225 
226 static inline uint32_t ref_totlen(struct jffs2_sb_info *c,
227 				  struct jffs2_eraseblock *jeb,
228 				  struct jffs2_raw_node_ref *ref)
229 {
230 	uint32_t ret;
231 
232 #if CONFIG_JFFS2_FS_DEBUG > 0
233 	if (jeb && jeb != &c->blocks[ref->flash_offset / c->sector_size]) {
234 		printk(KERN_CRIT "ref_totlen called with wrong block -- at 0x%08x instead of 0x%08x; ref 0x%08x\n",
235 		       jeb->offset, c->blocks[ref->flash_offset / c->sector_size].offset, ref_offset(ref));
236 		BUG();
237 	}
238 #endif
239 
240 #if 1
241 	ret = ref->__totlen;
242 #else
243 	/* This doesn't actually work yet */
244 	ret = __ref_totlen(c, jeb, ref);
245 	if (ret != ref->__totlen) {
246 		printk(KERN_CRIT "Totlen for ref at %p (0x%08x-0x%08x) miscalculated as 0x%x instead of %x\n",
247 		       ref, ref_offset(ref), ref_offset(ref)+ref->__totlen,
248 		       ret, ref->__totlen);
249 		if (!jeb)
250 			jeb = &c->blocks[ref->flash_offset / c->sector_size];
251 		jffs2_dbg_dump_node_refs_nolock(c, jeb);
252 		BUG();
253 	}
254 #endif
255 	return ret;
256 }
257 
258 #define ALLOC_NORMAL	0	/* Normal allocation */
259 #define ALLOC_DELETION	1	/* Deletion node. Best to allow it */
260 #define ALLOC_GC	2	/* Space requested for GC. Give it or die */
261 #define ALLOC_NORETRY	3	/* For jffs2_write_dnode: On failure, return -EAGAIN instead of retrying */
262 
263 /* How much dirty space before it goes on the very_dirty_list */
264 #define VERYDIRTY(c, size) ((size) >= ((c)->sector_size / 2))
265 
266 /* check if dirty space is more than 255 Byte */
267 #define ISDIRTY(size) ((size) >  sizeof (struct jffs2_raw_inode) + JFFS2_MIN_DATA_LEN)
268 
269 #define PAD(x) (((x)+3)&~3)
270 
271 static inline struct jffs2_inode_cache *jffs2_raw_ref_to_ic(struct jffs2_raw_node_ref *raw)
272 {
273 	while(raw->next_in_ino) {
274 		raw = raw->next_in_ino;
275 	}
276 
277 	return ((struct jffs2_inode_cache *)raw);
278 }
279 
280 static inline struct jffs2_node_frag *frag_first(struct rb_root *root)
281 {
282 	struct rb_node *node = root->rb_node;
283 
284 	if (!node)
285 		return NULL;
286 	while(node->rb_left)
287 		node = node->rb_left;
288 	return rb_entry(node, struct jffs2_node_frag, rb);
289 }
290 
291 static inline struct jffs2_node_frag *frag_last(struct rb_root *root)
292 {
293 	struct rb_node *node = root->rb_node;
294 
295 	if (!node)
296 		return NULL;
297 	while(node->rb_right)
298 		node = node->rb_right;
299 	return rb_entry(node, struct jffs2_node_frag, rb);
300 }
301 
302 #define rb_parent(rb) ((rb)->rb_parent)
303 #define frag_next(frag) rb_entry(rb_next(&(frag)->rb), struct jffs2_node_frag, rb)
304 #define frag_prev(frag) rb_entry(rb_prev(&(frag)->rb), struct jffs2_node_frag, rb)
305 #define frag_parent(frag) rb_entry(rb_parent(&(frag)->rb), struct jffs2_node_frag, rb)
306 #define frag_left(frag) rb_entry((frag)->rb.rb_left, struct jffs2_node_frag, rb)
307 #define frag_right(frag) rb_entry((frag)->rb.rb_right, struct jffs2_node_frag, rb)
308 #define frag_erase(frag, list) rb_erase(&frag->rb, list);
309 
310 /* nodelist.c */
311 void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new, struct jffs2_full_dirent **list);
312 void jffs2_set_inocache_state(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic, int state);
313 struct jffs2_inode_cache *jffs2_get_ino_cache(struct jffs2_sb_info *c, uint32_t ino);
314 void jffs2_add_ino_cache (struct jffs2_sb_info *c, struct jffs2_inode_cache *new);
315 void jffs2_del_ino_cache(struct jffs2_sb_info *c, struct jffs2_inode_cache *old);
316 void jffs2_free_ino_caches(struct jffs2_sb_info *c);
317 void jffs2_free_raw_node_refs(struct jffs2_sb_info *c);
318 struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_t offset);
319 void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c_delete);
320 struct rb_node *rb_next(struct rb_node *);
321 struct rb_node *rb_prev(struct rb_node *);
322 void rb_replace_node(struct rb_node *victim, struct rb_node *new, struct rb_root *root);
323 void jffs2_obsolete_node_frag(struct jffs2_sb_info *c, struct jffs2_node_frag *this);
324 int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_full_dnode *fn);
325 void jffs2_truncate_fragtree (struct jffs2_sb_info *c, struct rb_root *list, uint32_t size);
326 int jffs2_add_older_frag_to_fragtree(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_tmp_dnode_info *tn);
327 
328 /* nodemgmt.c */
329 int jffs2_thread_should_wake(struct jffs2_sb_info *c);
330 int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *ofs,
331 			uint32_t *len, int prio, uint32_t sumsize);
332 int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *ofs,
333 			uint32_t *len, uint32_t sumsize);
334 int jffs2_add_physical_node_ref(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *new);
335 void jffs2_complete_reservation(struct jffs2_sb_info *c);
336 void jffs2_mark_node_obsolete(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *raw);
337 
338 /* write.c */
339 int jffs2_do_new_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, uint32_t mode, struct jffs2_raw_inode *ri);
340 
341 struct jffs2_full_dnode *jffs2_write_dnode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_raw_inode *ri, const unsigned char *data, uint32_t datalen, uint32_t flash_ofs, int alloc_mode);
342 struct jffs2_full_dirent *jffs2_write_dirent(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_raw_dirent *rd, const unsigned char *name, uint32_t namelen, uint32_t flash_ofs, int alloc_mode);
343 int jffs2_write_inode_range(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
344 			    struct jffs2_raw_inode *ri, unsigned char *buf,
345 			    uint32_t offset, uint32_t writelen, uint32_t *retlen);
346 int jffs2_do_create(struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f, struct jffs2_inode_info *f, struct jffs2_raw_inode *ri, const char *name, int namelen);
347 int jffs2_do_unlink(struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f, const char *name, int namelen, struct jffs2_inode_info *dead_f, uint32_t time);
348 int jffs2_do_link (struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f, uint32_t ino, uint8_t type, const char *name, int namelen, uint32_t time);
349 
350 
351 /* readinode.c */
352 int jffs2_do_read_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
353 			uint32_t ino, struct jffs2_raw_inode *latest_node);
354 int jffs2_do_crccheck_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic);
355 void jffs2_do_clear_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f);
356 
357 /* malloc.c */
358 int jffs2_create_slab_caches(void);
359 void jffs2_destroy_slab_caches(void);
360 
361 struct jffs2_full_dirent *jffs2_alloc_full_dirent(int namesize);
362 void jffs2_free_full_dirent(struct jffs2_full_dirent *);
363 struct jffs2_full_dnode *jffs2_alloc_full_dnode(void);
364 void jffs2_free_full_dnode(struct jffs2_full_dnode *);
365 struct jffs2_raw_dirent *jffs2_alloc_raw_dirent(void);
366 void jffs2_free_raw_dirent(struct jffs2_raw_dirent *);
367 struct jffs2_raw_inode *jffs2_alloc_raw_inode(void);
368 void jffs2_free_raw_inode(struct jffs2_raw_inode *);
369 struct jffs2_tmp_dnode_info *jffs2_alloc_tmp_dnode_info(void);
370 void jffs2_free_tmp_dnode_info(struct jffs2_tmp_dnode_info *);
371 struct jffs2_raw_node_ref *jffs2_alloc_raw_node_ref(void);
372 void jffs2_free_raw_node_ref(struct jffs2_raw_node_ref *);
373 struct jffs2_node_frag *jffs2_alloc_node_frag(void);
374 void jffs2_free_node_frag(struct jffs2_node_frag *);
375 struct jffs2_inode_cache *jffs2_alloc_inode_cache(void);
376 void jffs2_free_inode_cache(struct jffs2_inode_cache *);
377 
378 /* gc.c */
379 int jffs2_garbage_collect_pass(struct jffs2_sb_info *c);
380 
381 /* read.c */
382 int jffs2_read_dnode(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
383 		     struct jffs2_full_dnode *fd, unsigned char *buf,
384 		     int ofs, int len);
385 int jffs2_read_inode_range(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
386 			   unsigned char *buf, uint32_t offset, uint32_t len);
387 char *jffs2_getlink(struct jffs2_sb_info *c, struct jffs2_inode_info *f);
388 
389 /* scan.c */
390 int jffs2_scan_medium(struct jffs2_sb_info *c);
391 void jffs2_rotate_lists(struct jffs2_sb_info *c);
392 int jffs2_fill_scan_buf(struct jffs2_sb_info *c, void *buf,
393 				uint32_t ofs, uint32_t len);
394 struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino);
395 int jffs2_scan_classify_jeb(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
396 
397 /* build.c */
398 int jffs2_do_mount_fs(struct jffs2_sb_info *c);
399 
400 /* erase.c */
401 void jffs2_erase_pending_blocks(struct jffs2_sb_info *c, int count);
402 
403 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
404 /* wbuf.c */
405 int jffs2_flush_wbuf_gc(struct jffs2_sb_info *c, uint32_t ino);
406 int jffs2_flush_wbuf_pad(struct jffs2_sb_info *c);
407 int jffs2_check_nand_cleanmarker(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
408 int jffs2_write_nand_cleanmarker(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
409 #endif
410 
411 #include "debug.h"
412 
413 #endif /* __JFFS2_NODELIST_H__ */
414