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 <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__ */