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         uint32_t __totlen; /* This may die; use ref_totlen(c, jeb, ) below */
  86 };
  87
  88         /* flash_offset & 3 always has to be zero, because nodes are
  89            always aligned at 4 bytes. So we have a couple of extra bits
  90            to play with, which indicate the node's status; see below: */
  91 #define REF_UNCHECKED   0       /* We haven't yet checked the CRC or built its inode */
  92 #define REF_OBSOLETE    1       /* Obsolete, can be completely ignored */
  93 #define REF_PRISTINE    2       /* Completely clean. GC without looking */
  94 #define REF_NORMAL      3       /* Possibly overlapped. Read the page and write again on GC */
  95 #define ref_flags(ref)          ((ref)->flash_offset & 3)
  96 #define ref_offset(ref)         ((ref)->flash_offset & ~3)
  97 #define ref_obsolete(ref)       (((ref)->flash_offset & 3) == REF_OBSOLETE)
  98 #define mark_ref_normal(ref)    do { (ref)->flash_offset = ref_offset(ref) | REF_NORMAL; } while(0)
  99
 100 /* NB: REF_PRISTINE for an inode-less node (ref->next_in_ino == NULL) indicates
 101    it is an unknown node of type JFFS2_NODETYPE_RWCOMPAT_COPY, so it'll get
 102    copied. If you need to do anything different to GC inode-less nodes, then
 103    you need to modify gc.c accordingly. */
 104
 105 /* For each inode in the filesystem, we need to keep a record of
 106    nlink, because it would be a PITA to scan the whole directory tree
 107    at read_inode() time to calculate it, and to keep sufficient information
 108    in the raw_node_ref (basically both parent and child inode number for
 109    dirent nodes) would take more space than this does. We also keep
 110    a pointer to the first physical node which is part of this inode, too.
 111 */
 112 struct jffs2_inode_cache {
 113         struct jffs2_full_dirent *scan_dents; /* Used during scan to hold
 114                 temporary lists of dirents, and later must be set to
 115                 NULL to mark the end of the raw_node_ref->next_in_ino
 116                 chain. */
 117         u8 class;       /* It's used for identification */
 118         u8 flags;
 119         uint16_t state;
 120         struct jffs2_inode_cache *next;
 121         struct jffs2_raw_node_ref *nodes;
 122         uint32_t ino;
 123         int nlink;
 124 #ifdef CONFIG_JFFS2_FS_XATTR
 125         struct jffs2_xattr_ref *xref;
 126 #endif
 127 };
 128
 129 /* Inode states for 'state' above. We need the 'GC' state to prevent
 130    someone from doing a read_inode() while we're moving a 'REF_PRISTINE'
 131    node without going through all the iget() nonsense */
 132 #define INO_STATE_UNCHECKED     0       /* CRC checks not yet done */
 133 #define INO_STATE_CHECKING      1       /* CRC checks in progress */
 134 #define INO_STATE_PRESENT       2       /* In core */
 135 #define INO_STATE_CHECKEDABSENT 3       /* Checked, cleared again */
 136 #define INO_STATE_GC            4       /* GCing a 'pristine' node */
 137 #define INO_STATE_READING       5       /* In read_inode() */
 138 #define INO_STATE_CLEARING      6       /* In clear_inode() */
 139
 140 #define INO_FLAGS_XATTR_CHECKED 0x01    /* has no duplicate xattr_ref */
 141
 142 #define RAWNODE_CLASS_INODE_CACHE       0
 143 #define RAWNODE_CLASS_XATTR_DATUM       1
 144 #define RAWNODE_CLASS_XATTR_REF         2
 145
 146 #define INOCACHE_HASHSIZE 128
 147
 148 /*
 149   Larger representation of a raw node, kept in-core only when the
 150   struct inode for this particular ino is instantiated.
 151 */
 152
 153 struct jffs2_full_dnode
 154 {
 155         struct jffs2_raw_node_ref *raw;
 156         uint32_t ofs; /* The offset to which the data of this node belongs */
 157         uint32_t size;
 158         uint32_t frags; /* Number of fragments which currently refer
 159                         to this node. When this reaches zero,
 160                         the node is obsolete.  */
 161 };
 162
 163 /*
 164    Even larger representation of a raw node, kept in-core only while
 165    we're actually building up the original map of which nodes go where,
 166    in read_inode()
 167 */
 168 struct jffs2_tmp_dnode_info
 169 {
 170         struct rb_node rb;
 171         struct jffs2_full_dnode *fn;
 172         uint32_t version;
 173         uint32_t data_crc;
 174         uint32_t partial_crc;
 175         uint32_t csize;
 176 };
 177
 178 struct jffs2_full_dirent
 179 {
 180         struct jffs2_raw_node_ref *raw;
 181         struct jffs2_full_dirent *next;
 182         uint32_t version;
 183         uint32_t ino; /* == zero for unlink */
 184         unsigned int nhash;
 185         unsigned char type;
 186         unsigned char name[0];
 187 };
 188
 189 /*
 190   Fragments - used to build a map of which raw node to obtain
 191   data from for each part of the ino
 192 */
 193 struct jffs2_node_frag
 194 {
 195         struct rb_node rb;
 196         struct jffs2_full_dnode *node; /* NULL for holes */
 197         uint32_t size;
 198         uint32_t ofs; /* The offset to which this fragment belongs */
 199 };
 200
 201 struct jffs2_eraseblock
 202 {
 203         struct list_head list;
 204         int bad_count;
 205         uint32_t offset;                /* of this block in the MTD */
 206
 207         uint32_t unchecked_size;
 208         uint32_t used_size;
 209         uint32_t dirty_size;
 210         uint32_t wasted_size;
 211         uint32_t free_size;     /* Note that sector_size - free_size
 212                                    is the address of the first free space */
 213         struct jffs2_raw_node_ref *first_node;
 214         struct jffs2_raw_node_ref *last_node;
 215
 216         struct jffs2_raw_node_ref *gc_node;     /* Next node to be garbage collected */
 217 };
 218
 219 static inline int jffs2_blocks_use_vmalloc(struct jffs2_sb_info *c)
 220 {
 221         return ((c->flash_size / c->sector_size) * sizeof (struct jffs2_eraseblock)) > (128 * 1024);
 222 }
 223
 224 /* Calculate totlen from surrounding nodes or eraseblock */
 225 static inline uint32_t __ref_totlen(struct jffs2_sb_info *c,
 226                                     struct jffs2_eraseblock *jeb,
 227                                     struct jffs2_raw_node_ref *ref)
 228 {
 229         uint32_t ref_end;
 230
 231         if (ref->next_phys)
 232                 ref_end = ref_offset(ref->next_phys);
 233         else {
 234                 if (!jeb)
 235                         jeb = &c->blocks[ref->flash_offset / c->sector_size];
 236
 237                 /* Last node in block. Use free_space */
 238                 BUG_ON(ref != jeb->last_node);
 239                 ref_end = jeb->offset + c->sector_size - jeb->free_size;
 240         }
 241         return ref_end - ref_offset(ref);
 242 }
 243
 244 static inline uint32_t ref_totlen(struct jffs2_sb_info *c,
 245                                   struct jffs2_eraseblock *jeb,
 246                                   struct jffs2_raw_node_ref *ref)
 247 {
 248         uint32_t ret;
 249
 250 #if CONFIG_JFFS2_FS_DEBUG > 0
 251         if (jeb && jeb != &c->blocks[ref->flash_offset / c->sector_size]) {
 252                 printk(KERN_CRIT "ref_totlen called with wrong block -- at 0x%08x instead of 0x%08x; ref 0x%08x\n",
 253                        jeb->offset, c->blocks[ref->flash_offset / c->sector_size].offset, ref_offset(ref));
 254                 BUG();
 255         }
 256 #endif
 257
 258 #if 1
 259         ret = ref->__totlen;
 260 #else
 261         /* This doesn't actually work yet */
 262         ret = __ref_totlen(c, jeb, ref);
 263         if (ret != ref->__totlen) {
 264                 printk(KERN_CRIT "Totlen for ref at %p (0x%08x-0x%08x) miscalculated as 0x%x instead of %x\n",
 265                        ref, ref_offset(ref), ref_offset(ref)+ref->__totlen,
 266                        ret, ref->__totlen);
 267                 if (!jeb)
 268                         jeb = &c->blocks[ref->flash_offset / c->sector_size];
 269                 jffs2_dbg_dump_node_refs_nolock(c, jeb);
 270                 BUG();
 271         }
 272 #endif
 273         return ret;
 274 }
 275
 276 #define ALLOC_NORMAL    0       /* Normal allocation */
 277 #define ALLOC_DELETION  1       /* Deletion node. Best to allow it */
 278 #define ALLOC_GC        2       /* Space requested for GC. Give it or die */
 279 #define ALLOC_NORETRY   3       /* For jffs2_write_dnode: On failure, return -EAGAIN instead of retrying */
 280
 281 /* How much dirty space before it goes on the very_dirty_list */
 282 #define VERYDIRTY(c, size) ((size) >= ((c)->sector_size / 2))
 283
 284 /* check if dirty space is more than 255 Byte */
 285 #define ISDIRTY(size) ((size) >  sizeof (struct jffs2_raw_inode) + JFFS2_MIN_DATA_LEN)
 286
 287 #define PAD(x) (((x)+3)&~3)
 288
 289 static inline int jffs2_encode_dev(union jffs2_device_node *jdev, dev_t rdev)
 290 {
 291         if (old_valid_dev(rdev)) {
 292                 jdev->old = cpu_to_je16(old_encode_dev(rdev));
 293                 return sizeof(jdev->old);
 294         } else {
 295                 jdev->new = cpu_to_je32(new_encode_dev(rdev));
 296                 return sizeof(jdev->new);
 297         }
 298 }
 299
 300 static inline struct jffs2_inode_cache *jffs2_raw_ref_to_ic(struct jffs2_raw_node_ref *raw)
 301 {
 302         while(raw->next_in_ino) {
 303                 raw = raw->next_in_ino;
 304         }
 305
 306         return ((struct jffs2_inode_cache *)raw);
 307 }
 308
 309 static inline struct jffs2_node_frag *frag_first(struct rb_root *root)
 310 {
 311         struct rb_node *node = root->rb_node;
 312
 313         if (!node)
 314                 return NULL;
 315         while(node->rb_left)
 316                 node = node->rb_left;
 317         return rb_entry(node, struct jffs2_node_frag, rb);
 318 }
 319
 320 static inline struct jffs2_node_frag *frag_last(struct rb_root *root)
 321 {
 322         struct rb_node *node = root->rb_node;
 323
 324         if (!node)
 325                 return NULL;
 326         while(node->rb_right)
 327                 node = node->rb_right;
 328         return rb_entry(node, struct jffs2_node_frag, rb);
 329 }
 330
 331 #define rb_parent(rb) ((rb)->rb_parent)
 332 #define frag_next(frag) rb_entry(rb_next(&(frag)->rb), struct jffs2_node_frag, rb)
 333 #define frag_prev(frag) rb_entry(rb_prev(&(frag)->rb), struct jffs2_node_frag, rb)
 334 #define frag_parent(frag) rb_entry(rb_parent(&(frag)->rb), struct jffs2_node_frag, rb)
 335 #define frag_left(frag) rb_entry((frag)->rb.rb_left, struct jffs2_node_frag, rb)
 336 #define frag_right(frag) rb_entry((frag)->rb.rb_right, struct jffs2_node_frag, rb)
 337 #define frag_erase(frag, list) rb_erase(&frag->rb, list);
 338
 339 /* nodelist.c */
 340 void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new, struct jffs2_full_dirent **list);
 341 void jffs2_set_inocache_state(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic, int state);
 342 struct jffs2_inode_cache *jffs2_get_ino_cache(struct jffs2_sb_info *c, uint32_t ino);
 343 void jffs2_add_ino_cache (struct jffs2_sb_info *c, struct jffs2_inode_cache *new);
 344 void jffs2_del_ino_cache(struct jffs2_sb_info *c, struct jffs2_inode_cache *old);
 345 void jffs2_free_ino_caches(struct jffs2_sb_info *c);
 346 void jffs2_free_raw_node_refs(struct jffs2_sb_info *c);
 347 struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_t offset);
 348 void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c_delete);
 349 struct rb_node *rb_next(struct rb_node *);
 350 struct rb_node *rb_prev(struct rb_node *);
 351 void rb_replace_node(struct rb_node *victim, struct rb_node *new, struct rb_root *root);
 352 void jffs2_obsolete_node_frag(struct jffs2_sb_info *c, struct jffs2_node_frag *this);
 353 int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_full_dnode *fn);
 354 void jffs2_truncate_fragtree (struct jffs2_sb_info *c, struct rb_root *list, uint32_t size);
 355 int jffs2_add_older_frag_to_fragtree(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_tmp_dnode_info *tn);
 356 void jffs2_link_node_ref(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
 357                          struct jffs2_raw_node_ref *ref, uint32_t len);
 358
 359 /* nodemgmt.c */
 360 int jffs2_thread_should_wake(struct jffs2_sb_info *c);
 361 int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *ofs,
 362                         uint32_t *len, int prio, uint32_t sumsize);
 363 int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize, uint32_t *ofs,
 364                         uint32_t *len, uint32_t sumsize);
 365 int jffs2_add_physical_node_ref(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *new, uint32_t len);
 366 void jffs2_complete_reservation(struct jffs2_sb_info *c);
 367 void jffs2_mark_node_obsolete(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *raw);
 368
 369 /* write.c */
 370 int jffs2_do_new_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, uint32_t mode, struct jffs2_raw_inode *ri);
 371
 372 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);
 373 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);
 374 int jffs2_write_inode_range(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
 375                             struct jffs2_raw_inode *ri, unsigned char *buf,
 376                             uint32_t offset, uint32_t writelen, uint32_t *retlen);
 377 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);
 378 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);
 379 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);
 380
 381
 382 /* readinode.c */
 383 int jffs2_do_read_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
 384                         uint32_t ino, struct jffs2_raw_inode *latest_node);
 385 int jffs2_do_crccheck_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic);
 386 void jffs2_do_clear_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f);
 387
 388 /* malloc.c */
 389 int jffs2_create_slab_caches(void);
 390 void jffs2_destroy_slab_caches(void);
 391
 392 struct jffs2_full_dirent *jffs2_alloc_full_dirent(int namesize);
 393 void jffs2_free_full_dirent(struct jffs2_full_dirent *);
 394 struct jffs2_full_dnode *jffs2_alloc_full_dnode(void);
 395 void jffs2_free_full_dnode(struct jffs2_full_dnode *);
 396 struct jffs2_raw_dirent *jffs2_alloc_raw_dirent(void);
 397 void jffs2_free_raw_dirent(struct jffs2_raw_dirent *);
 398 struct jffs2_raw_inode *jffs2_alloc_raw_inode(void);
 399 void jffs2_free_raw_inode(struct jffs2_raw_inode *);
 400 struct jffs2_tmp_dnode_info *jffs2_alloc_tmp_dnode_info(void);
 401 void jffs2_free_tmp_dnode_info(struct jffs2_tmp_dnode_info *);
 402 struct jffs2_raw_node_ref *jffs2_alloc_raw_node_ref(void);
 403 void jffs2_free_raw_node_ref(struct jffs2_raw_node_ref *);
 404 struct jffs2_node_frag *jffs2_alloc_node_frag(void);
 405 void jffs2_free_node_frag(struct jffs2_node_frag *);
 406 struct jffs2_inode_cache *jffs2_alloc_inode_cache(void);
 407 void jffs2_free_inode_cache(struct jffs2_inode_cache *);
 408 #ifdef CONFIG_JFFS2_FS_XATTR
 409 struct jffs2_xattr_datum *jffs2_alloc_xattr_datum(void);
 410 void jffs2_free_xattr_datum(struct jffs2_xattr_datum *);
 411 struct jffs2_xattr_ref *jffs2_alloc_xattr_ref(void);
 412 void jffs2_free_xattr_ref(struct jffs2_xattr_ref *);
 413 #endif
 414
 415 /* gc.c */
 416 int jffs2_garbage_collect_pass(struct jffs2_sb_info *c);
 417
 418 /* read.c */
 419 int jffs2_read_dnode(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
 420                      struct jffs2_full_dnode *fd, unsigned char *buf,
 421                      int ofs, int len);
 422 int jffs2_read_inode_range(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
 423                            unsigned char *buf, uint32_t offset, uint32_t len);
 424 char *jffs2_getlink(struct jffs2_sb_info *c, struct jffs2_inode_info *f);
 425
 426 /* scan.c */
 427 int jffs2_scan_medium(struct jffs2_sb_info *c);
 428 void jffs2_rotate_lists(struct jffs2_sb_info *c);
 429 int jffs2_fill_scan_buf(struct jffs2_sb_info *c, void *buf,
 430                                 uint32_t ofs, uint32_t len);
 431 struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino);
 432 int jffs2_scan_classify_jeb(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
 433 int jffs2_scan_dirty_space(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t size);
 434
 435 /* build.c */
 436 int jffs2_do_mount_fs(struct jffs2_sb_info *c);
 437
 438 /* erase.c */
 439 void jffs2_erase_pending_blocks(struct jffs2_sb_info *c, int count);
 440 void jffs2_free_all_node_refs(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
 441
 442 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
 443 /* wbuf.c */
 444 int jffs2_flush_wbuf_gc(struct jffs2_sb_info *c, uint32_t ino);
 445 int jffs2_flush_wbuf_pad(struct jffs2_sb_info *c);
 446 int jffs2_check_nand_cleanmarker(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
 447 int jffs2_write_nand_cleanmarker(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
 448 #endif
 449
 450 #include "debug.h"
 451
 452 #endif /* __JFFS2_NODELIST_H__ */