nodelist.h (18322B)
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(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__ */