mm: do_migrate_pages() calls migrate_to_node() even if task is already on a correct...
[linux/fpc-iii.git] / fs / jffs2 / nodelist.h
blobe4619b00f7c5dec65669f0b1dd9acdf135392185
1 /*
2 * JFFS2 -- Journalling Flash File System, Version 2.
4 * Copyright © 2001-2007 Red Hat, Inc.
6 * Created by David Woodhouse <dwmw2@infradead.org>
8 * For licensing information, see the file 'LICENCE' in this directory.
12 #ifndef __JFFS2_NODELIST_H__
13 #define __JFFS2_NODELIST_H__
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"
24 #ifdef __ECOS
25 #include "os-ecos.h"
26 #else
27 #include "os-linux.h"
28 #endif
30 #define JFFS2_NATIVE_ENDIAN
32 /* Note we handle mode bits conversion from JFFS2 (i.e. Linux) to/from
33 whatever OS we're actually running on here too. */
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)})
40 #define constant_cpu_to_je16(x) ((jint16_t){x})
41 #define constant_cpu_to_je32(x) ((jint32_t){x})
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))})
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)})
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))})
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)})
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
72 /* The minimal node header size */
73 #define JFFS2_MIN_NODE_HEADER sizeof(struct jffs2_raw_dirent)
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.
82 struct jffs2_raw_node_ref
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
95 #define REF_LINK_NODE ((int32_t)-1)
96 #define REF_EMPTY_NODE ((int32_t)-2)
98 /* Use blocks of about 256 bytes */
99 #define REFS_PER_BLOCK ((255/sizeof(struct jffs2_raw_node_ref))-1)
101 static inline struct jffs2_raw_node_ref *ref_next(struct jffs2_raw_node_ref *ref)
103 ref++;
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;
112 /* End of chain */
113 if (ref->flash_offset == REF_EMPTY_NODE)
114 return NULL;
116 return ref;
119 static inline struct jffs2_inode_cache *jffs2_raw_ref_to_ic(struct jffs2_raw_node_ref *raw)
121 while(raw->next_in_ino)
122 raw = raw->next_in_ino;
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);
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)
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) )
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. */
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.
158 struct 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. */
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 */
170 /* end of shared structure */
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. */
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() */
196 #define INO_FLAGS_XATTR_CHECKED 0x01 /* has no duplicate xattr_ref */
198 #define RAWNODE_CLASS_INODE_CACHE 0
199 #define RAWNODE_CLASS_XATTR_DATUM 1
200 #define RAWNODE_CLASS_XATTR_REF 2
202 #define INOCACHE_HASHSIZE_MIN 128
203 #define INOCACHE_HASHSIZE_MAX 1024
205 #define write_ofs(c) ((c)->nextblock->offset + (c)->sector_size - (c)->nextblock->free_size)
208 Larger representation of a raw node, kept in-core only when the
209 struct inode for this particular ino is instantiated.
212 struct jffs2_full_dnode
214 struct jffs2_raw_node_ref *raw;
215 uint32_t ofs; /* The offset to which the data of this node belongs */
216 uint32_t size;
217 uint32_t frags; /* Number of fragments which currently refer
218 to this node. When this reaches zero,
219 the node is obsolete. */
223 Even larger representation of a raw node, kept in-core only while
224 we're actually building up the original map of which nodes go where,
225 in read_inode()
227 struct jffs2_tmp_dnode_info
229 struct rb_node rb;
230 struct jffs2_full_dnode *fn;
231 uint32_t version;
232 uint32_t data_crc;
233 uint32_t partial_crc;
234 uint16_t csize;
235 uint16_t overlapped;
238 /* Temporary data structure used during readinode. */
239 struct jffs2_readinode_info
241 struct rb_root tn_root;
242 struct jffs2_tmp_dnode_info *mdata_tn;
243 uint32_t highest_version;
244 uint32_t latest_mctime;
245 uint32_t mctime_ver;
246 struct jffs2_full_dirent *fds;
247 struct jffs2_raw_node_ref *latest_ref;
250 struct jffs2_full_dirent
252 struct jffs2_raw_node_ref *raw;
253 struct jffs2_full_dirent *next;
254 uint32_t version;
255 uint32_t ino; /* == zero for unlink */
256 unsigned int nhash;
257 unsigned char type;
258 unsigned char name[0];
262 Fragments - used to build a map of which raw node to obtain
263 data from for each part of the ino
265 struct jffs2_node_frag
267 struct rb_node rb;
268 struct jffs2_full_dnode *node; /* NULL for holes */
269 uint32_t size;
270 uint32_t ofs; /* The offset to which this fragment belongs */
273 struct jffs2_eraseblock
275 struct list_head list;
276 int bad_count;
277 uint32_t offset; /* of this block in the MTD */
279 uint32_t unchecked_size;
280 uint32_t used_size;
281 uint32_t dirty_size;
282 uint32_t wasted_size;
283 uint32_t free_size; /* Note that sector_size - free_size
284 is the address of the first free space */
285 uint32_t allocated_refs;
286 struct jffs2_raw_node_ref *first_node;
287 struct jffs2_raw_node_ref *last_node;
289 struct jffs2_raw_node_ref *gc_node; /* Next node to be garbage collected */
292 static inline int jffs2_blocks_use_vmalloc(struct jffs2_sb_info *c)
294 return ((c->flash_size / c->sector_size) * sizeof (struct jffs2_eraseblock)) > (128 * 1024);
297 #define ref_totlen(a, b, c) __jffs2_ref_totlen((a), (b), (c))
299 #define ALLOC_NORMAL 0 /* Normal allocation */
300 #define ALLOC_DELETION 1 /* Deletion node. Best to allow it */
301 #define ALLOC_GC 2 /* Space requested for GC. Give it or die */
302 #define ALLOC_NORETRY 3 /* For jffs2_write_dnode: On failure, return -EAGAIN instead of retrying */
304 /* How much dirty space before it goes on the very_dirty_list */
305 #define VERYDIRTY(c, size) ((size) >= ((c)->sector_size / 2))
307 /* check if dirty space is more than 255 Byte */
308 #define ISDIRTY(size) ((size) > sizeof (struct jffs2_raw_inode) + JFFS2_MIN_DATA_LEN)
310 #define PAD(x) (((x)+3)&~3)
312 static inline int jffs2_encode_dev(union jffs2_device_node *jdev, dev_t rdev)
314 if (old_valid_dev(rdev)) {
315 jdev->old_id = cpu_to_je16(old_encode_dev(rdev));
316 return sizeof(jdev->old_id);
317 } else {
318 jdev->new_id = cpu_to_je32(new_encode_dev(rdev));
319 return sizeof(jdev->new_id);
323 static inline struct jffs2_node_frag *frag_first(struct rb_root *root)
325 struct rb_node *node = rb_first(root);
327 if (!node)
328 return NULL;
330 return rb_entry(node, struct jffs2_node_frag, rb);
333 static inline struct jffs2_node_frag *frag_last(struct rb_root *root)
335 struct rb_node *node = rb_last(root);
337 if (!node)
338 return NULL;
340 return rb_entry(node, struct jffs2_node_frag, rb);
343 #define frag_next(frag) rb_entry(rb_next(&(frag)->rb), struct jffs2_node_frag, rb)
344 #define frag_prev(frag) rb_entry(rb_prev(&(frag)->rb), struct jffs2_node_frag, rb)
345 #define frag_parent(frag) rb_entry(rb_parent(&(frag)->rb), struct jffs2_node_frag, rb)
346 #define frag_left(frag) rb_entry((frag)->rb.rb_left, struct jffs2_node_frag, rb)
347 #define frag_right(frag) rb_entry((frag)->rb.rb_right, struct jffs2_node_frag, rb)
348 #define frag_erase(frag, list) rb_erase(&frag->rb, list);
350 #define tn_next(tn) rb_entry(rb_next(&(tn)->rb), struct jffs2_tmp_dnode_info, rb)
351 #define tn_prev(tn) rb_entry(rb_prev(&(tn)->rb), struct jffs2_tmp_dnode_info, rb)
352 #define tn_parent(tn) rb_entry(rb_parent(&(tn)->rb), struct jffs2_tmp_dnode_info, rb)
353 #define tn_left(tn) rb_entry((tn)->rb.rb_left, struct jffs2_tmp_dnode_info, rb)
354 #define tn_right(tn) rb_entry((tn)->rb.rb_right, struct jffs2_tmp_dnode_info, rb)
355 #define tn_erase(tn, list) rb_erase(&tn->rb, list);
356 #define tn_last(list) rb_entry(rb_last(list), struct jffs2_tmp_dnode_info, rb)
357 #define tn_first(list) rb_entry(rb_first(list), struct jffs2_tmp_dnode_info, rb)
359 /* nodelist.c */
360 void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new, struct jffs2_full_dirent **list);
361 void jffs2_set_inocache_state(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic, int state);
362 struct jffs2_inode_cache *jffs2_get_ino_cache(struct jffs2_sb_info *c, uint32_t ino);
363 void jffs2_add_ino_cache (struct jffs2_sb_info *c, struct jffs2_inode_cache *new);
364 void jffs2_del_ino_cache(struct jffs2_sb_info *c, struct jffs2_inode_cache *old);
365 void jffs2_free_ino_caches(struct jffs2_sb_info *c);
366 void jffs2_free_raw_node_refs(struct jffs2_sb_info *c);
367 struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_t offset);
368 void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c_delete);
369 int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_full_dnode *fn);
370 uint32_t jffs2_truncate_fragtree (struct jffs2_sb_info *c, struct rb_root *list, uint32_t size);
371 struct jffs2_raw_node_ref *jffs2_link_node_ref(struct jffs2_sb_info *c,
372 struct jffs2_eraseblock *jeb,
373 uint32_t ofs, uint32_t len,
374 struct jffs2_inode_cache *ic);
375 extern uint32_t __jffs2_ref_totlen(struct jffs2_sb_info *c,
376 struct jffs2_eraseblock *jeb,
377 struct jffs2_raw_node_ref *ref);
379 /* nodemgmt.c */
380 int jffs2_thread_should_wake(struct jffs2_sb_info *c);
381 int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize,
382 uint32_t *len, int prio, uint32_t sumsize);
383 int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize,
384 uint32_t *len, uint32_t sumsize);
385 struct jffs2_raw_node_ref *jffs2_add_physical_node_ref(struct jffs2_sb_info *c,
386 uint32_t ofs, uint32_t len,
387 struct jffs2_inode_cache *ic);
388 void jffs2_complete_reservation(struct jffs2_sb_info *c);
389 void jffs2_mark_node_obsolete(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *raw);
391 /* write.c */
392 int jffs2_do_new_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, uint32_t mode, struct jffs2_raw_inode *ri);
394 struct jffs2_full_dnode *jffs2_write_dnode(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
395 struct jffs2_raw_inode *ri, const unsigned char *data,
396 uint32_t datalen, int alloc_mode);
397 struct jffs2_full_dirent *jffs2_write_dirent(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
398 struct jffs2_raw_dirent *rd, const unsigned char *name,
399 uint32_t namelen, int alloc_mode);
400 int jffs2_write_inode_range(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
401 struct jffs2_raw_inode *ri, unsigned char *buf,
402 uint32_t offset, uint32_t writelen, uint32_t *retlen);
403 int jffs2_do_create(struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f, struct jffs2_inode_info *f,
404 struct jffs2_raw_inode *ri, const struct qstr *qstr);
405 int jffs2_do_unlink(struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f, const char *name,
406 int namelen, struct jffs2_inode_info *dead_f, uint32_t time);
407 int jffs2_do_link(struct jffs2_sb_info *c, struct jffs2_inode_info *dir_f, uint32_t ino,
408 uint8_t type, const char *name, int namelen, uint32_t time);
411 /* readinode.c */
412 int jffs2_do_read_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
413 uint32_t ino, struct jffs2_raw_inode *latest_node);
414 int jffs2_do_crccheck_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic);
415 void jffs2_do_clear_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f);
417 /* malloc.c */
418 int jffs2_create_slab_caches(void);
419 void jffs2_destroy_slab_caches(void);
421 struct jffs2_full_dirent *jffs2_alloc_full_dirent(int namesize);
422 void jffs2_free_full_dirent(struct jffs2_full_dirent *);
423 struct jffs2_full_dnode *jffs2_alloc_full_dnode(void);
424 void jffs2_free_full_dnode(struct jffs2_full_dnode *);
425 struct jffs2_raw_dirent *jffs2_alloc_raw_dirent(void);
426 void jffs2_free_raw_dirent(struct jffs2_raw_dirent *);
427 struct jffs2_raw_inode *jffs2_alloc_raw_inode(void);
428 void jffs2_free_raw_inode(struct jffs2_raw_inode *);
429 struct jffs2_tmp_dnode_info *jffs2_alloc_tmp_dnode_info(void);
430 void jffs2_free_tmp_dnode_info(struct jffs2_tmp_dnode_info *);
431 int jffs2_prealloc_raw_node_refs(struct jffs2_sb_info *c,
432 struct jffs2_eraseblock *jeb, int nr);
433 void jffs2_free_refblock(struct jffs2_raw_node_ref *);
434 struct jffs2_node_frag *jffs2_alloc_node_frag(void);
435 void jffs2_free_node_frag(struct jffs2_node_frag *);
436 struct jffs2_inode_cache *jffs2_alloc_inode_cache(void);
437 void jffs2_free_inode_cache(struct jffs2_inode_cache *);
438 #ifdef CONFIG_JFFS2_FS_XATTR
439 struct jffs2_xattr_datum *jffs2_alloc_xattr_datum(void);
440 void jffs2_free_xattr_datum(struct jffs2_xattr_datum *);
441 struct jffs2_xattr_ref *jffs2_alloc_xattr_ref(void);
442 void jffs2_free_xattr_ref(struct jffs2_xattr_ref *);
443 #endif
445 /* gc.c */
446 int jffs2_garbage_collect_pass(struct jffs2_sb_info *c);
448 /* read.c */
449 int jffs2_read_dnode(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
450 struct jffs2_full_dnode *fd, unsigned char *buf,
451 int ofs, int len);
452 int jffs2_read_inode_range(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
453 unsigned char *buf, uint32_t offset, uint32_t len);
454 char *jffs2_getlink(struct jffs2_sb_info *c, struct jffs2_inode_info *f);
456 /* scan.c */
457 int jffs2_scan_medium(struct jffs2_sb_info *c);
458 void jffs2_rotate_lists(struct jffs2_sb_info *c);
459 struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino);
460 int jffs2_scan_classify_jeb(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
461 int jffs2_scan_dirty_space(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t size);
463 /* build.c */
464 int jffs2_do_mount_fs(struct jffs2_sb_info *c);
466 /* erase.c */
467 int jffs2_erase_pending_blocks(struct jffs2_sb_info *c, int count);
468 void jffs2_free_jeb_node_refs(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
470 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
471 /* wbuf.c */
472 int jffs2_flush_wbuf_gc(struct jffs2_sb_info *c, uint32_t ino);
473 int jffs2_flush_wbuf_pad(struct jffs2_sb_info *c);
474 int jffs2_check_nand_cleanmarker(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
475 int jffs2_write_nand_cleanmarker(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
476 #endif
478 #include "debug.h"
480 #endif /* __JFFS2_NODELIST_H__ */