fs/jffs2/nodelist.h

   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 "jffs2_fs_sb.h"
  22 #include "jffs2_fs_i.h"
  23 #include "xattr.h"
  24 #include "acl.h"
  25 #include "summary.h"
  26
  27 #ifdef __ECOS
  28 #include "os-ecos.h"
  29 #else
  30 #include <linux/mtd/compatmac.h> /* For compatibility with older kernels */
  31 #include "os-linux.h"
  32 #endif
  33
  34 #define JFFS2_NATIVE_ENDIAN
  35
  36 /* Note we handle mode bits conversion from JFFS2 (i.e. Linux) to/from
  37    whatever OS we're actually running on here too. */
  38
  39 #if defined(JFFS2_NATIVE_ENDIAN)
  40 #define cpu_to_je16(x) ((jint16_t){x})
  41 #define cpu_to_je32(x) ((jint32_t){x})
  42 #define cpu_to_jemode(x) ((jmode_t){os_to_jffs2_mode(x)})
  43
  44 #define je16_to_cpu(x) ((x).v16)
  45 #define je32_to_cpu(x) ((x).v32)
  46 #define jemode_to_cpu(x) (jffs2_to_os_mode((x).m))
  47 #elif defined(JFFS2_BIG_ENDIAN)
  48 #define cpu_to_je16(x) ((jint16_t){cpu_to_be16(x)})
  49 #define cpu_to_je32(x) ((jint32_t){cpu_to_be32(x)})
  50 #define cpu_to_jemode(x) ((jmode_t){cpu_to_be32(os_to_jffs2_mode(x))})
  51
  52 #define je16_to_cpu(x) (be16_to_cpu(x.v16))
  53 #define je32_to_cpu(x) (be32_to_cpu(x.v32))
  54 #define jemode_to_cpu(x) (be32_to_cpu(jffs2_to_os_mode((x).m)))
  55 #elif defined(JFFS2_LITTLE_ENDIAN)
  56 #define cpu_to_je16(x) ((jint16_t){cpu_to_le16(x)})
  57 #define cpu_to_je32(x) ((jint32_t){cpu_to_le32(x)})
  58 #define cpu_to_jemode(x) ((jmode_t){cpu_to_le32(os_to_jffs2_mode(x))})
  59
  60 #define je16_to_cpu(x) (le16_to_cpu(x.v16))
  61 #define je32_to_cpu(x) (le32_to_cpu(x.v32))
  62 #define jemode_to_cpu(x) (le32_to_cpu(jffs2_to_os_mode((x).m)))
  63 #else
  64 #error wibble
  65 #endif
  66
  67 /* The minimal node header size */
  68 #define JFFS2_MIN_NODE_HEADER sizeof(struct jffs2_raw_dirent)
  69
  70 /*
  71   This is all we need to keep in-core for each raw node during normal
  72   operation. As and when we do read_inode on a particular inode, we can
  73   scan the nodes which are listed for it and build up a proper map of
  74   which nodes are currently valid. JFFSv1 always used to keep that whole
  75   map in core for each inode.
  76 */
  77 struct jffs2_raw_node_ref
  78 {
  79         struct jffs2_raw_node_ref *next_in_ino; /* Points to the next raw_node_ref
  80                 for this inode. If this is the last, it points to the inode_cache
  81                 for this inode instead. The inode_cache will have NULL in the first
  82                 word so you know when you've got there :) */
  83         struct jffs2_raw_node_ref *next_phys;
  84         uint32_t flash_offset;
  85 #define TEST_TOTLEN
  86 #ifdef TEST_TOTLEN
  87         uint32_t __totlen; /* This may die; use ref_totlen(c, jeb, ) below */
  88 #endif
  89 };
  90
  91         /* flash_offset & 3 always has to be zero, because nodes are
  92            always aligned at 4 bytes. So we have a couple of extra bits
  93            to play with, which indicate the node's status; see below: */
  94 #define REF_UNCHECKED   0       /* We haven't yet checked the CRC or built its inode */
  95 #define REF_OBSOLETE    1       /* Obsolete, can be completely ignored */
  96 #define REF_PRISTINE    2       /* Completely clean. GC without looking */
  97 #define REF_NORMAL      3       /* Possibly overlapped. Read the page and write again on GC */
  98 #define ref_flags(ref)          ((ref)->flash_offset & 3)
  99 #define ref_offset(ref)         ((ref)->flash_offset & ~3)
 100 #define ref_obsolete(ref)       (((ref)->flash_offset & 3) == REF_OBSOLETE)
 101 #define mark_ref_normal(ref)    do { (ref)->flash_offset = ref_offset(ref) | REF_NORMAL; } while(0)
 102
 103 /* NB: REF_PRISTINE for an inode-less node (ref->next_in_ino == NULL) indicates
 104    it is an unknown node of type JFFS2_NODETYPE_RWCOMPAT_COPY, so it'll get
 105    copied. If you need to do anything different to GC inode-less nodes, then
 106    you need to modify gc.c accordingly. */
 107
 108 /* For each inode in the filesystem, we need to keep a record of
 109    nlink, because it would be a PITA to scan the whole directory tree
 110    at read_inode() time to calculate it, and to keep sufficient information
 111    in the raw_node_ref (basically both parent and child inode number for
 112    dirent nodes) would take more space than this does. We also keep
 113    a pointer to the first physical node which is part of this inode, too.
 114 */
 115 struct jffs2_inode_cache {
 116         struct jffs2_full_dirent *scan_dents; /* Used during scan to hold
 117                 temporary lists of dirents, and later must be set to
 118                 NULL to mark the end of the raw_node_ref->next_in_ino
 119                 chain. */
 120         u8 class;       /* It's used for identification */
 121         u8 flags;
 122         uint16_t state;
 123         struct jffs2_inode_cache *next;
 124         struct jffs2_raw_node_ref *nodes;
 125         uint32_t ino;
 126         int nlink;
 127 #ifdef CONFIG_JFFS2_FS_XATTR
 128         struct jffs2_xattr_ref *xref;
 129 #endif
 130 };
 131
 132 /* Inode states for 'state' above. We need the 'GC' state to prevent
 133    someone from doing a read_inode() while we're moving a 'REF_PRISTINE'
 134    node without going through all the iget() nonsense */
 135 #define INO_STATE_UNCHECKED     0       /* CRC checks not yet done */
 136 #define INO_STATE_CHECKING      1       /* CRC checks in progress */
 137 #define INO_STATE_PRESENT       2       /* In core */
 138 #define INO_STATE_CHECKEDABSENT 3       /* Checked, cleared again */
 139 #define INO_STATE_GC            4       /* GCing a 'pristine' node */
 140 #define INO_STATE_READING       5       /* In read_inode() */
 141 #define INO_STATE_CLEARING      6       /* In clear_inode() */
 142
 143 #define INO_FLAGS_XATTR_CHECKED 0x01    /* has no duplicate xattr_ref */
 144
 145 #define RAWNODE_CLASS_INODE_CACHE       0
 146 #define RAWNODE_CLASS_XATTR_DATUM       1
 147 #define RAWNODE_CLASS_XATTR_REF         2
 148
 149 #define INOCACHE_HASHSIZE 128
 150
 151 /*
 152   Larger representation of a raw node, kept in-core only when the
 153   struct inode for this particular ino is instantiated.
 154 */
 155
 156 struct jffs2_full_dnode
 157 {
 158         struct jffs2_raw_node_ref *raw;
 159         uint32_t ofs; /* The offset to which the data of this node belongs */
 160         uint32_t size;
 161         uint32_t frags; /* Number of fragments which currently refer
 162                         to this node. When this reaches zero,
 163                         the node is obsolete.  */
 164 };
 165
 166 /*
 167    Even larger representation of a raw node, kept in-core only while
 168    we're actually building up the original map of which nodes go where,
 169    in read_inode()
 170 */
 171 struct jffs2_tmp_dnode_info
 172 {
 173         struct rb_node rb;
 174         struct jffs2_full_dnode *fn;
 175         uint32_t version;
 176         uint32_t data_crc;
 177         uint32_t partial_crc;
 178         uint32_t csize;
 179 };
 180
 181 struct jffs2_full_dirent
 182 {
 183         struct jffs2_raw_node_ref *raw;
 184         struct jffs2_full_dirent *next;
 185         uint32_t version;
 186         uint32_t ino; /* == zero for unlink */
 187         unsigned int nhash;
 188         unsigned char type;
 189         unsigned char name[0];
 190 };
 191
 192 /*
 193   Fragments - used to build a map of which raw node to obtain
 194   data from for each part of the ino
 195 */
 196 struct jffs2_node_frag
 197 {
 198         struct rb_node rb;
 199         struct jffs2_full_dnode *node; /* NULL for holes */
 200         uint32_t size;
 201         uint32_t ofs; /* The offset to which this fragment belongs */
 202 };
 203
 204 struct jffs2_eraseblock
 205 {
 206         struct list_head list;
 207         int bad_count;
 208         uint32_t offset;                /* of this block in the MTD */
 209
 210         uint32_t unchecked_size;
 211         uint32_t used_size;
 212         uint32_t dirty_size;
 213         uint32_t wasted_size;
 214         uint32_t free_size;     /* Note that sector_size - free_size
 215                                    is the address of the first free space */
 216         struct jffs2_raw_node_ref *first_node;
 217         struct jffs2_raw_node_ref *last_node;
 218
 219         struct jffs2_raw_node_ref *gc_node;     /* Next node to be garbage collected */
 220 };
 221
 222 static inline int jffs2_blocks_use_vmalloc(struct jffs2_sb_info *c)
 223 {
 224         return ((c->flash_size / c->sector_size) * sizeof (struct jffs2_eraseblock)) > (128 * 1024);
 225 }
 226
 227 #define ref_totlen(a, b, c) __jffs2_ref_totlen((a), (b), (c))
 228
 229 #define ALLOC_NORMAL    0       /* Normal allocation */
 230 #define ALLOC_DELETION  1       /* Deletion node. Best to allow it */
 231 #define ALLOC_GC        2       /* Space requested for GC. Give it or die */
 232 #define ALLOC_NORETRY   3       /* For jffs2_write_dnode: On failure, return -EAGAIN instead of retrying */
 233
 234 /* How much dirty space before it goes on the very_dirty_list */
 235 #define VERYDIRTY(c, size) ((size) >= ((c)->sector_size / 2))
 236
 237 /* check if dirty space is more than 255 Byte */
 238 #define ISDIRTY(size) ((size) >  sizeof (struct jffs2_raw_inode) + JFFS2_MIN_DATA_LEN)
 239
 240 #define PAD(x) (((x)+3)&~3)
 241
 242 static inline int jffs2_encode_dev(union jffs2_device_node *jdev, dev_t rdev)
 243 {
 244         if (old_valid_dev(rdev)) {
 245                 jdev->old = cpu_to_je16(old_encode_dev(rdev));
 246                 return sizeof(jdev->old);
 247         } else {
 248                 jdev->new = cpu_to_je32(new_encode_dev(rdev));
 249                 return sizeof(jdev->new);
 250         }
 251 }
 252
 253 static inline struct jffs2_inode_cache *jffs2_raw_ref_to_ic(struct jffs2_raw_node_ref *raw)
 254 {
 255         while(raw->next_in_ino) {
 256                 raw = raw->next_in_ino;
 257         }
 258
 259         return ((struct jffs2_inode_cache *)raw);
 260 }
 261
 262 static inline struct jffs2_node_frag *frag_first(struct rb_root *root)
 263 {
 264         struct rb_node *node = root->rb_node;
 265
 266         if (!node)
 267                 return NULL;
 268         while(node->rb_left)
 269                 node = node->rb_left;
 270         return rb_entry(node, struct jffs2_node_frag, rb);
 271 }
 272
 273 static inline struct jffs2_node_frag *frag_last(struct rb_root *root)
 274 {
 275         struct rb_node *node = root->rb_node;
 276
 277         if (!node)
 278                 return NULL;
 279         while(node->rb_right)
 280                 node = node->rb_right;
 281         return rb_entry(node, struct jffs2_node_frag, rb);
 282 }
 283
 284 #define rb_parent(rb) ((rb)->rb_parent)
 285 #define frag_next(frag) rb_entry(rb_next(&(frag)->rb), struct jffs2_node_frag, rb)
 286 #define frag_prev(frag) rb_entry(rb_prev(&(frag)->rb), struct jffs2_node_frag, rb)
 287 #define frag_parent(frag) rb_entry(rb_parent(&(frag)->rb), struct jffs2_node_frag, rb)
 288 #define frag_left(frag) rb_entry((frag)->rb.rb_left, struct jffs2_node_frag, rb)
 289 #define frag_right(frag) rb_entry((frag)->rb.rb_right, struct jffs2_node_frag, rb)
 290 #define frag_erase(frag, list) rb_erase(&frag->rb, list);
 291
 292 /* nodelist.c */
 293 void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new, struct jffs2_full_dirent **list);
 294 void jffs2_set_inocache_state(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic, int state);
 295 struct jffs2_inode_cache *jffs2_get_ino_cache(struct jffs2_sb_info *c, uint32_t ino);
 296 void jffs2_add_ino_cache (struct jffs2_sb_info *c, struct jffs2_inode_cache *new);
 297 void jffs2_del_ino_cache(struct jffs2_sb_info *c, struct jffs2_inode_cache *old);
 298 void jffs2_free_ino_caches(struct jffs2_sb_info *c);
 299 void jffs2_free_raw_node_refs(struct jffs2_sb_info *c);
 300 struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_t offset);
 301 void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c_delete);
 302 struct rb_node *rb_next(struct rb_node *);
 303 struct rb_node *rb_prev(struct rb_node *);
 304 void rb_replace_node(struct rb_node *victim, struct rb_node *new, struct rb_root *root);
 305 void jffs2_obsolete_node_frag(struct jffs2_sb_info *c, struct jffs2_node_frag *this);
 306 int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_full_dnode *fn);
 307 void jffs2_truncate_fragtree (struct jffs2_sb_info *c, struct rb_root *list, uint32_t size);
 308 int jffs2_add_older_frag_to_fragtree(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_tmp_dnode_info *tn);
 309 void jffs2_link_node_ref(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
 310                          struct jffs2_raw_node_ref *ref, uint32_t len,
 311                          struct jffs2_inode_cache *ic);
 312 extern uint32_t __jffs2_ref_totlen(struct jffs2_sb_info *c,
 313                                    struct jffs2_eraseblock *jeb,
 314                                    struct jffs2_raw_node_ref *ref);
 315
 316 /* nodemgmt.c */
 317 int jffs2_thread_should_wake(struct jffs2_sb_info *c);
 318 int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *ofs,
 319                         uint32_t *len, int prio, uint32_t sumsize);
 320 int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *ofs,
 321                         uint32_t *len, uint32_t sumsize);
 322 int jffs2_add_physical_node_ref(struct jffs2_sb_info *c,
 323                                 struct jffs2_raw_node_ref *new,
 324                                 uint32_t len,
 325                                 struct jffs2_inode_cache *ic);
 326 void jffs2_complete_reservation(struct jffs2_sb_info *c);
 327 void jffs2_mark_node_obsolete(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *raw);
 328
 329 /* write.c */
 330 int jffs2_do_new_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, uint32_t mode, struct jffs2_raw_inode *ri);
 331
 332 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);
 333 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);
 334 int jffs2_write_inode_range(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
 335                             struct jffs2_raw_inode *ri, unsigned char *buf,
 336                             uint32_t offset, uint32_t writelen, uint32_t *retlen);
 337 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);
 338 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);
 339 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);
 340
 341
 342 /* readinode.c */
 343 int jffs2_do_read_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
 344                         uint32_t ino, struct jffs2_raw_inode *latest_node);
 345 int jffs2_do_crccheck_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic);
 346 void jffs2_do_clear_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f);
 347
 348 /* malloc.c */
 349 int jffs2_create_slab_caches(void);
 350 void jffs2_destroy_slab_caches(void);
 351
 352 struct jffs2_full_dirent *jffs2_alloc_full_dirent(int namesize);
 353 void jffs2_free_full_dirent(struct jffs2_full_dirent *);
 354 struct jffs2_full_dnode *jffs2_alloc_full_dnode(void);
 355 void jffs2_free_full_dnode(struct jffs2_full_dnode *);
 356 struct jffs2_raw_dirent *jffs2_alloc_raw_dirent(void);
 357 void jffs2_free_raw_dirent(struct jffs2_raw_dirent *);
 358 struct jffs2_raw_inode *jffs2_alloc_raw_inode(void);
 359 void jffs2_free_raw_inode(struct jffs2_raw_inode *);
 360 struct jffs2_tmp_dnode_info *jffs2_alloc_tmp_dnode_info(void);
 361 void jffs2_free_tmp_dnode_info(struct jffs2_tmp_dnode_info *);
 362 struct jffs2_raw_node_ref *jffs2_alloc_raw_node_ref(void);
 363 void jffs2_free_raw_node_ref(struct jffs2_raw_node_ref *);
 364 struct jffs2_node_frag *jffs2_alloc_node_frag(void);
 365 void jffs2_free_node_frag(struct jffs2_node_frag *);
 366 struct jffs2_inode_cache *jffs2_alloc_inode_cache(void);
 367 void jffs2_free_inode_cache(struct jffs2_inode_cache *);
 368 #ifdef CONFIG_JFFS2_FS_XATTR
 369 struct jffs2_xattr_datum *jffs2_alloc_xattr_datum(void);
 370 void jffs2_free_xattr_datum(struct jffs2_xattr_datum *);
 371 struct jffs2_xattr_ref *jffs2_alloc_xattr_ref(void);
 372 void jffs2_free_xattr_ref(struct jffs2_xattr_ref *);
 373 #endif
 374
 375 /* gc.c */
 376 int jffs2_garbage_collect_pass(struct jffs2_sb_info *c);
 377
 378 /* read.c */
 379 int jffs2_read_dnode(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
 380                      struct jffs2_full_dnode *fd, unsigned char *buf,
 381                      int ofs, int len);
 382 int jffs2_read_inode_range(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
 383                            unsigned char *buf, uint32_t offset, uint32_t len);
 384 char *jffs2_getlink(struct jffs2_sb_info *c, struct jffs2_inode_info *f);
 385
 386 /* scan.c */
 387 int jffs2_scan_medium(struct jffs2_sb_info *c);
 388 void jffs2_rotate_lists(struct jffs2_sb_info *c);
 389 int jffs2_fill_scan_buf(struct jffs2_sb_info *c, void *buf,
 390                                 uint32_t ofs, uint32_t len);
 391 struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino);
 392 int jffs2_scan_classify_jeb(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
 393 int jffs2_scan_dirty_space(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t size);
 394
 395 /* build.c */
 396 int jffs2_do_mount_fs(struct jffs2_sb_info *c);
 397
 398 /* erase.c */
 399 void jffs2_erase_pending_blocks(struct jffs2_sb_info *c, int count);
 400 void jffs2_free_all_node_refs(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
 401
 402 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
 403 /* wbuf.c */
 404 int jffs2_flush_wbuf_gc(struct jffs2_sb_info *c, uint32_t ino);
 405 int jffs2_flush_wbuf_pad(struct jffs2_sb_info *c);
 406 int jffs2_check_nand_cleanmarker(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
 407 int jffs2_write_nand_cleanmarker(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
 408 #endif
 409
 410 #include "debug.h"
 411
 412 #endif /* __JFFS2_NODELIST_H__ */