1/*
2 * JFFS2 -- Journalling Flash File System, Version 2.
3 *
4 * Copyright © 2001-2007 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 */
11
12#ifndef __JFFS2_NODELIST_H__
13#define __JFFS2_NODELIST_H__
14
15#include <linux/fs.h>
16#include <linux/types.h>
17#include <linux/jffs2.h>
18#include "jffs2_fs_sb.h"
19#include "jffs2_fs_i.h"
20#include "xattr.h"
21#include "acl.h"
22#include "summary.h"
23
24#ifdef __ECOS
25#include "os-ecos.h"
26#else
27#include "os-linux.h"
28#endif
29
30#define JFFS2_NATIVE_ENDIAN
31
32/* Note we handle mode bits conversion from JFFS2 (i.e. Linux) to/from
33 whatever OS we're actually running on here too. */
34
35#if defined(JFFS2_NATIVE_ENDIAN)
36#define cpu_to_je16(x) ((jint16_t){x})
37#define cpu_to_je32(x) ((jint32_t){x})
38#define cpu_to_jemode(x) ((jmode_t){os_to_jffs2_mode(x)})
39
40#define constant_cpu_to_je16(x) ((jint16_t){x})
41#define constant_cpu_to_je32(x) ((jint32_t){x})
42
43#define je16_to_cpu(x) ((x).v16)
44#define je32_to_cpu(x) ((x).v32)
45#define jemode_to_cpu(x) (jffs2_to_os_mode((x).m))
46#elif defined(JFFS2_BIG_ENDIAN)
47#define cpu_to_je16(x) ((jint16_t){cpu_to_be16(x)})
48#define cpu_to_je32(x) ((jint32_t){cpu_to_be32(x)})
49#define cpu_to_jemode(x) ((jmode_t){cpu_to_be32(os_to_jffs2_mode(x))})
50
51#define constant_cpu_to_je16(x) ((jint16_t){__constant_cpu_to_be16(x)})
52#define constant_cpu_to_je32(x) ((jint32_t){__constant_cpu_to_be32(x)})
53
54#define je16_to_cpu(x) (be16_to_cpu(x.v16))
55#define je32_to_cpu(x) (be32_to_cpu(x.v32))
56#define jemode_to_cpu(x) (be32_to_cpu(jffs2_to_os_mode((x).m)))
57#elif defined(JFFS2_LITTLE_ENDIAN)
58#define cpu_to_je16(x) ((jint16_t){cpu_to_le16(x)})
59#define cpu_to_je32(x) ((jint32_t){cpu_to_le32(x)})
60#define cpu_to_jemode(x) ((jmode_t){cpu_to_le32(os_to_jffs2_mode(x))})
61
62#define constant_cpu_to_je16(x) ((jint16_t){__constant_cpu_to_le16(x)})
63#define constant_cpu_to_je32(x) ((jint32_t){__constant_cpu_to_le32(x)})
64
65#define je16_to_cpu(x) (le16_to_cpu(x.v16))
66#define je32_to_cpu(x) (le32_to_cpu(x.v32))
67#define jemode_to_cpu(x) (le32_to_cpu(jffs2_to_os_mode((x).m)))
68#else
69#error wibble
70#endif
71
72/* The minimal node header size */
73#define JFFS2_MIN_NODE_HEADER sizeof(struct jffs2_raw_dirent)
74
75/*
76 This is all we need to keep in-core for each raw node during normal
77 operation. As and when we do read_inode on a particular inode, we can
78 scan the nodes which are listed for it and build up a proper map of
79 which nodes are currently valid. JFFSv1 always used to keep that whole
80 map in core for each inode.
81*/
82struct jffs2_raw_node_ref
83{
84 struct jffs2_raw_node_ref *next_in_ino; /* Points to the next raw_node_ref
85 for this object. If this _is_ the last, it points to the inode_cache,
86 xattr_ref or xattr_datum instead. The common part of those structures
87 has NULL in the first word. See jffs2_raw_ref_to_ic() below */
88 uint32_t flash_offset;
89#undef TEST_TOTLEN
90#ifdef TEST_TOTLEN
91 uint32_t __totlen; /* This may die; use ref_totlen(c, jeb, ) below */
92#endif
93};
94
95#define REF_LINK_NODE ((int32_t)-1)
96#define REF_EMPTY_NODE ((int32_t)-2)
97
98/* Use blocks of about 256 bytes */
99#define REFS_PER_BLOCK ((255/sizeof(struct jffs2_raw_node_ref))-1)
100
101static inline struct jffs2_raw_node_ref *ref_next(struct jffs2_raw_node_ref *ref)
102{
103 ref++;
104
105 /* Link to another block of refs */
106 if (ref->flash_offset == REF_LINK_NODE) {
107 ref = ref->next_in_ino;
108 if (!ref)
109 return ref;
110 }
111
112 /* End of chain */
113 if (ref->flash_offset == REF_EMPTY_NODE)
114 return NULL;
115
116 return ref;
117}
118
119static inline struct jffs2_inode_cache *jffs2_raw_ref_to_ic(struct jffs2_raw_node_ref *raw)
120{
121 while(raw->next_in_ino)
122 raw = raw->next_in_ino;
123
124 /* NB. This can be a jffs2_xattr_datum or jffs2_xattr_ref and
125 not actually a jffs2_inode_cache. Check ->class */
126 return ((struct jffs2_inode_cache *)raw);
127}
128
129 /* flash_offset & 3 always has to be zero, because nodes are
130 always aligned at 4 bytes. So we have a couple of extra bits
131 to play with, which indicate the node's status; see below: */
132#define REF_UNCHECKED 0 /* We haven't yet checked the CRC or built its inode */
133#define REF_OBSOLETE 1 /* Obsolete, can be completely ignored */
134#define REF_PRISTINE 2 /* Completely clean. GC without looking */
135#define REF_NORMAL 3 /* Possibly overlapped. Read the page and write again on GC */
136#define ref_flags(ref) ((ref)->flash_offset & 3)
137#define ref_offset(ref) ((ref)->flash_offset & ~3)
138#define ref_obsolete(ref) (((ref)->flash_offset & 3) == REF_OBSOLETE)
139#define mark_ref_normal(ref) do { (ref)->flash_offset = ref_offset(ref) | REF_NORMAL; } while(0)
140
141/* Dirent nodes should be REF_PRISTINE only if they are not a deletion
142 dirent. Deletion dirents should be REF_NORMAL so that GC gets to
143 throw them away when appropriate */
144#define dirent_node_state(rd) ( (je32_to_cpu((rd)->ino)?REF_PRISTINE:REF_NORMAL) )
145
146/* NB: REF_PRISTINE for an inode-less node (ref->next_in_ino == NULL) indicates
147 it is an unknown node of type JFFS2_NODETYPE_RWCOMPAT_COPY, so it'll get
148 copied. If you need to do anything different to GC inode-less nodes, then
149 you need to modify gc.c accordingly. */
150
151/* For each inode in the filesystem, we need to keep a record of
152 nlink, because it would be a PITA to scan the whole directory tree
153 at read_inode() time to calculate it, and to keep sufficient information
154 in the raw_node_ref (basically both parent and child inode number for
155 dirent nodes) would take more space than this does. We also keep
156 a pointer to the first physical node which is part of this inode, too.
157*/
158struct jffs2_inode_cache {
159 /* First part of structure is shared with other objects which
160 can terminate the raw node refs' next_in_ino list -- which
161 currently struct jffs2_xattr_datum and struct jffs2_xattr_ref. */
162
163 struct jffs2_full_dirent *scan_dents; /* Used during scan to hold
164 temporary lists of dirents, and later must be set to
165 NULL to mark the end of the raw_node_ref->next_in_ino
166 chain. */
167 struct jffs2_raw_node_ref *nodes;
168 uint8_t class; /* It's used for identification */
169
170 /* end of shared structure */
171
172 uint8_t flags;
173 uint16_t state;
174 uint32_t ino;
175 struct jffs2_inode_cache *next;
176#ifdef CONFIG_JFFS2_FS_XATTR
177 struct jffs2_xattr_ref *xref;
178#endif
179 uint32_t pino_nlink; /* Directories store parent inode
180 here; other inodes store nlink.
181 Zero always means that it's
182 completely unlinked. */
183};
184
185/* Inode states for 'state' above. We need the 'GC' state to prevent
186 someone from doing a read_inode() while we're moving a 'REF_PRISTINE'
187 node without going through all the iget() nonsense */
188#define INO_STATE_UNCHECKED 0 /* CRC checks not yet done */
189#define INO_STATE_CHECKING 1 /* CRC checks in progress */
190#define INO_STATE_PRESENT 2 /* In core */
191#define INO_STATE_CHECKEDABSENT 3 /* Checked, cleared again */
192#define INO_STATE_GC 4 /* GCing a 'pristine' node */
193#define INO_STATE_READING 5 /* In read_inode() */
194#define INO_STATE_CLEARING 6 /* In clear_inode() */
195
196#define INO_FLAGS_XATTR_CHECKED 0x01 /* has no duplicate xattr_ref */
197#define INO_FLAGS_IS_DIR 0x02 /* is a directory */
198
199#define RAWNODE_CLASS_INODE_CACHE 0
200#define RAWNODE_CLASS_XATTR_DATUM 1
201#define RAWNODE_CLASS_XATTR_REF 2
202
203#define INOCACHE_HASHSIZE_MIN 128
204#define INOCACHE_HASHSIZE_MAX 1024
205
206#define write_ofs(c) ((c)->nextblock->offset + (c)->sector_size - (c)->nextblock->free_size)
207
208/*
209 Larger representation of a raw node, kept in-core only when the
210 struct inode for this particular ino is instantiated.
211*/
212
213struct jffs2_full_dnode
214{
215 struct jffs2_raw_node_ref *raw;
216 uint32_t ofs; /* The offset to which the data of this node belongs */
217 uint32_t size;
218 uint32_t frags; /* Number of fragments which currently refer
219 to this node. When this reaches zero,
220 the node is obsolete. */
221};
222
223/*
224 Even larger representation of a raw node, kept in-core only while
225 we're actually building up the original map of which nodes go where,
226 in read_inode()
227*/
228struct jffs2_tmp_dnode_info
229{
230 struct rb_node rb;
231 struct jffs2_full_dnode *fn;
232 uint32_t version;
233 uint32_t data_crc;
234 uint32_t partial_crc;
235 uint32_t csize;
236 uint16_t overlapped;
237};
238
239/* Temporary data structure used during readinode. */
240struct jffs2_readinode_info
241{
242 struct rb_root tn_root;
243 struct jffs2_tmp_dnode_info *mdata_tn;
244 uint32_t highest_version;
245 uint32_t latest_mctime;
246 uint32_t mctime_ver;
247 struct jffs2_full_dirent *fds;
248 struct jffs2_raw_node_ref *latest_ref;
249};
250
251struct jffs2_full_dirent
252{
253 union {
254 struct jffs2_raw_node_ref *raw;
255 struct jffs2_inode_cache *ic; /* Just during part of build */
256 };
257 struct jffs2_full_dirent *next;
258 uint32_t version;
259 uint32_t ino; /* == zero for unlink */
260 unsigned int nhash;
261 unsigned char type;
262 unsigned char name[];
263};
264
265/*
266 Fragments - used to build a map of which raw node to obtain
267 data from for each part of the ino
268*/
269struct jffs2_node_frag
270{
271 struct rb_node rb;
272 struct jffs2_full_dnode *node; /* NULL for holes */
273 uint32_t size;
274 uint32_t ofs; /* The offset to which this fragment belongs */
275};
276
277struct jffs2_eraseblock
278{
279 struct list_head list;
280 int bad_count;
281 uint32_t offset; /* of this block in the MTD */
282
283 uint32_t unchecked_size;
284 uint32_t used_size;
285 uint32_t dirty_size;
286 uint32_t wasted_size;
287 uint32_t free_size; /* Note that sector_size - free_size
288 is the address of the first free space */
289 uint32_t allocated_refs;
290 struct jffs2_raw_node_ref *first_node;
291 struct jffs2_raw_node_ref *last_node;
292
293 struct jffs2_raw_node_ref *gc_node; /* Next node to be garbage collected */
294};
295
296static inline int jffs2_blocks_use_vmalloc(struct jffs2_sb_info *c)
297{
298 return ((c->flash_size / c->sector_size) * sizeof (struct jffs2_eraseblock)) > (128 * 1024);
299}
300
301#define ref_totlen(a, b, c) __jffs2_ref_totlen((a), (b), (c))
302
303#define ALLOC_NORMAL 0 /* Normal allocation */
304#define ALLOC_DELETION 1 /* Deletion node. Best to allow it */
305#define ALLOC_GC 2 /* Space requested for GC. Give it or die */
306#define ALLOC_NORETRY 3 /* For jffs2_write_dnode: On failure, return -EAGAIN instead of retrying */
307
308/* How much dirty space before it goes on the very_dirty_list */
309#define VERYDIRTY(c, size) ((size) >= ((c)->sector_size / 2))
310
311/* check if dirty space is more than 255 Byte */
312#define ISDIRTY(size) ((size) > sizeof (struct jffs2_raw_inode) + JFFS2_MIN_DATA_LEN)
313
314#define PAD(x) (((x)+3)&~3)
315
316static inline int jffs2_encode_dev(union jffs2_device_node *jdev, dev_t rdev)
317{
318 if (old_valid_dev(dev: rdev)) {
319 jdev->old_id = cpu_to_je16(old_encode_dev(rdev));
320 return sizeof(jdev->old_id);
321 } else {
322 jdev->new_id = cpu_to_je32(new_encode_dev(rdev));
323 return sizeof(jdev->new_id);
324 }
325}
326
327static inline struct jffs2_node_frag *frag_first(struct rb_root *root)
328{
329 struct rb_node *node = rb_first(root);
330
331 if (!node)
332 return NULL;
333
334 return rb_entry(node, struct jffs2_node_frag, rb);
335}
336
337static inline struct jffs2_node_frag *frag_last(struct rb_root *root)
338{
339 struct rb_node *node = rb_last(root);
340
341 if (!node)
342 return NULL;
343
344 return rb_entry(node, struct jffs2_node_frag, rb);
345}
346
347#define frag_next(frag) rb_entry(rb_next(&(frag)->rb), struct jffs2_node_frag, rb)
348#define frag_prev(frag) rb_entry(rb_prev(&(frag)->rb), struct jffs2_node_frag, rb)
349#define frag_parent(frag) rb_entry(rb_parent(&(frag)->rb), struct jffs2_node_frag, rb)
350#define frag_left(frag) rb_entry((frag)->rb.rb_left, struct jffs2_node_frag, rb)
351#define frag_right(frag) rb_entry((frag)->rb.rb_right, struct jffs2_node_frag, rb)
352#define frag_erase(frag, list) rb_erase(&frag->rb, list)
353
354#define tn_next(tn) rb_entry(rb_next(&(tn)->rb), struct jffs2_tmp_dnode_info, rb)
355#define tn_prev(tn) rb_entry(rb_prev(&(tn)->rb), struct jffs2_tmp_dnode_info, rb)
356#define tn_parent(tn) rb_entry(rb_parent(&(tn)->rb), struct jffs2_tmp_dnode_info, rb)
357#define tn_left(tn) rb_entry((tn)->rb.rb_left, struct jffs2_tmp_dnode_info, rb)
358#define tn_right(tn) rb_entry((tn)->rb.rb_right, struct jffs2_tmp_dnode_info, rb)
359#define tn_erase(tn, list) rb_erase(&tn->rb, list)
360#define tn_last(list) rb_entry(rb_last(list), struct jffs2_tmp_dnode_info, rb)
361#define tn_first(list) rb_entry(rb_first(list), struct jffs2_tmp_dnode_info, rb)
362
363/* nodelist.c */
364void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new, struct jffs2_full_dirent **list);
365void jffs2_set_inocache_state(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic, int state);
366struct jffs2_inode_cache *jffs2_get_ino_cache(struct jffs2_sb_info *c, uint32_t ino);
367void jffs2_add_ino_cache (struct jffs2_sb_info *c, struct jffs2_inode_cache *new);
368void jffs2_del_ino_cache(struct jffs2_sb_info *c, struct jffs2_inode_cache *old);
369void jffs2_free_ino_caches(struct jffs2_sb_info *c);
370void jffs2_free_raw_node_refs(struct jffs2_sb_info *c);
371struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_t offset);
372void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c_delete);
373int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_full_dnode *fn);
374uint32_t jffs2_truncate_fragtree (struct jffs2_sb_info *c, struct rb_root *list, uint32_t size);
375struct jffs2_raw_node_ref *jffs2_link_node_ref(struct jffs2_sb_info *c,
376 struct jffs2_eraseblock *jeb,
377 uint32_t ofs, uint32_t len,
378 struct jffs2_inode_cache *ic);
379extern uint32_t __jffs2_ref_totlen(struct jffs2_sb_info *c,
380 struct jffs2_eraseblock *jeb,
381 struct jffs2_raw_node_ref *ref);
382
383/* nodemgmt.c */
384int jffs2_thread_should_wake(struct jffs2_sb_info *c);
385int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize,
386 uint32_t *len, int prio, uint32_t sumsize);
387int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize,
388 uint32_t *len, uint32_t sumsize);
389struct jffs2_raw_node_ref *jffs2_add_physical_node_ref(struct jffs2_sb_info *c,
390 uint32_t ofs, uint32_t len,
391 struct jffs2_inode_cache *ic);
392void jffs2_complete_reservation(struct jffs2_sb_info *c);
393void jffs2_mark_node_obsolete(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *raw);
394
395/* write.c */
396int jffs2_do_new_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, uint32_t mode, struct jffs2_raw_inode *ri);
397
398struct jffs2_full_dnode *jffs2_write_dnode(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
399 struct jffs2_raw_inode *ri, const unsigned char *data,
400 uint32_t datalen, int alloc_mode);
401struct jffs2_full_dirent *jffs2_write_dirent(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
402 struct jffs2_raw_dirent *rd, const unsigned char *name,
403 uint32_t namelen, int alloc_mode);
404int jffs2_write_inode_range(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
405 struct jffs2_raw_inode *ri, unsigned char *buf,
406 uint32_t offset, uint32_t writelen, uint32_t *retlen);
407int jffs2_do_create(struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f, struct jffs2_inode_info *f,
408 struct jffs2_raw_inode *ri, const struct qstr *qstr);
409int jffs2_do_unlink(struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f, const char *name,
410 int namelen, struct jffs2_inode_info *dead_f, uint32_t time);
411int jffs2_do_link(struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f, uint32_t ino,
412 uint8_t type, const char *name, int namelen, uint32_t time);
413
414
415/* readinode.c */
416int jffs2_do_read_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
417 uint32_t ino, struct jffs2_raw_inode *latest_node);
418int jffs2_do_crccheck_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic);
419void jffs2_do_clear_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f);
420
421/* malloc.c */
422int jffs2_create_slab_caches(void);
423void jffs2_destroy_slab_caches(void);
424
425struct jffs2_full_dirent *jffs2_alloc_full_dirent(int namesize);
426void jffs2_free_full_dirent(struct jffs2_full_dirent *);
427struct jffs2_full_dnode *jffs2_alloc_full_dnode(void);
428void jffs2_free_full_dnode(struct jffs2_full_dnode *);
429struct jffs2_raw_dirent *jffs2_alloc_raw_dirent(void);
430void jffs2_free_raw_dirent(struct jffs2_raw_dirent *);
431struct jffs2_raw_inode *jffs2_alloc_raw_inode(void);
432void jffs2_free_raw_inode(struct jffs2_raw_inode *);
433struct jffs2_tmp_dnode_info *jffs2_alloc_tmp_dnode_info(void);
434void jffs2_free_tmp_dnode_info(struct jffs2_tmp_dnode_info *);
435int jffs2_prealloc_raw_node_refs(struct jffs2_sb_info *c,
436 struct jffs2_eraseblock *jeb, int nr);
437void jffs2_free_refblock(struct jffs2_raw_node_ref *);
438struct jffs2_node_frag *jffs2_alloc_node_frag(void);
439void jffs2_free_node_frag(struct jffs2_node_frag *);
440struct jffs2_inode_cache *jffs2_alloc_inode_cache(void);
441void jffs2_free_inode_cache(struct jffs2_inode_cache *);
442#ifdef CONFIG_JFFS2_FS_XATTR
443struct jffs2_xattr_datum *jffs2_alloc_xattr_datum(void);
444void jffs2_free_xattr_datum(struct jffs2_xattr_datum *);
445struct jffs2_xattr_ref *jffs2_alloc_xattr_ref(void);
446void jffs2_free_xattr_ref(struct jffs2_xattr_ref *);
447#endif
448
449/* gc.c */
450int jffs2_garbage_collect_pass(struct jffs2_sb_info *c);
451
452/* read.c */
453int jffs2_read_dnode(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
454 struct jffs2_full_dnode *fd, unsigned char *buf,
455 int ofs, int len);
456int jffs2_read_inode_range(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
457 unsigned char *buf, uint32_t offset, uint32_t len);
458char *jffs2_getlink(struct jffs2_sb_info *c, struct jffs2_inode_info *f);
459
460/* scan.c */
461int jffs2_scan_medium(struct jffs2_sb_info *c);
462void jffs2_rotate_lists(struct jffs2_sb_info *c);
463struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino);
464int jffs2_scan_classify_jeb(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
465int jffs2_scan_dirty_space(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t size);
466
467/* build.c */
468int jffs2_do_mount_fs(struct jffs2_sb_info *c);
469
470/* erase.c */
471int jffs2_erase_pending_blocks(struct jffs2_sb_info *c, int count);
472void jffs2_free_jeb_node_refs(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
473
474#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
475/* wbuf.c */
476int jffs2_flush_wbuf_gc(struct jffs2_sb_info *c, uint32_t ino);
477int jffs2_flush_wbuf_pad(struct jffs2_sb_info *c);
478int jffs2_check_nand_cleanmarker(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
479int jffs2_write_nand_cleanmarker(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
480#endif
481
482#include "debug.h"
483
484#endif /* __JFFS2_NODELIST_H__ */
485

source code of linux/fs/jffs2/nodelist.h