diff options
Diffstat (limited to 'fs/jffs2/scan.c')
-rw-r--r-- | fs/jffs2/scan.c | 916 |
1 files changed, 916 insertions, 0 deletions
diff --git a/fs/jffs2/scan.c b/fs/jffs2/scan.c new file mode 100644 index 00000000000..ded53584a89 --- /dev/null +++ b/fs/jffs2/scan.c @@ -0,0 +1,916 @@ +/* + * JFFS2 -- Journalling Flash File System, Version 2. + * + * Copyright (C) 2001-2003 Red Hat, Inc. + * + * Created by David Woodhouse <dwmw2@infradead.org> + * + * For licensing information, see the file 'LICENCE' in this directory. + * + * $Id: scan.c,v 1.115 2004/11/17 12:59:08 dedekind Exp $ + * + */ +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/mtd/mtd.h> +#include <linux/pagemap.h> +#include <linux/crc32.h> +#include <linux/compiler.h> +#include "nodelist.h" + +#define EMPTY_SCAN_SIZE 1024 + +#define DIRTY_SPACE(x) do { typeof(x) _x = (x); \ + c->free_size -= _x; c->dirty_size += _x; \ + jeb->free_size -= _x ; jeb->dirty_size += _x; \ + }while(0) +#define USED_SPACE(x) do { typeof(x) _x = (x); \ + c->free_size -= _x; c->used_size += _x; \ + jeb->free_size -= _x ; jeb->used_size += _x; \ + }while(0) +#define UNCHECKED_SPACE(x) do { typeof(x) _x = (x); \ + c->free_size -= _x; c->unchecked_size += _x; \ + jeb->free_size -= _x ; jeb->unchecked_size += _x; \ + }while(0) + +#define noisy_printk(noise, args...) do { \ + if (*(noise)) { \ + printk(KERN_NOTICE args); \ + (*(noise))--; \ + if (!(*(noise))) { \ + printk(KERN_NOTICE "Further such events for this erase block will not be printed\n"); \ + } \ + } \ +} while(0) + +static uint32_t pseudo_random; + +static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, + unsigned char *buf, uint32_t buf_size); + +/* These helper functions _must_ increase ofs and also do the dirty/used space accounting. + * Returning an error will abort the mount - bad checksums etc. should just mark the space + * as dirty. + */ +static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, + struct jffs2_raw_inode *ri, uint32_t ofs); +static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, + struct jffs2_raw_dirent *rd, uint32_t ofs); + +#define BLK_STATE_ALLFF 0 +#define BLK_STATE_CLEAN 1 +#define BLK_STATE_PARTDIRTY 2 +#define BLK_STATE_CLEANMARKER 3 +#define BLK_STATE_ALLDIRTY 4 +#define BLK_STATE_BADBLOCK 5 + +static inline int min_free(struct jffs2_sb_info *c) +{ + uint32_t min = 2 * sizeof(struct jffs2_raw_inode); +#if defined CONFIG_JFFS2_FS_NAND || defined CONFIG_JFFS2_FS_NOR_ECC + if (!jffs2_can_mark_obsolete(c) && min < c->wbuf_pagesize) + return c->wbuf_pagesize; +#endif + return min; + +} +int jffs2_scan_medium(struct jffs2_sb_info *c) +{ + int i, ret; + uint32_t empty_blocks = 0, bad_blocks = 0; + unsigned char *flashbuf = NULL; + uint32_t buf_size = 0; +#ifndef __ECOS + size_t pointlen; + + if (c->mtd->point) { + ret = c->mtd->point (c->mtd, 0, c->mtd->size, &pointlen, &flashbuf); + if (!ret && pointlen < c->mtd->size) { + /* Don't muck about if it won't let us point to the whole flash */ + D1(printk(KERN_DEBUG "MTD point returned len too short: 0x%zx\n", pointlen)); + c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size); + flashbuf = NULL; + } + if (ret) + D1(printk(KERN_DEBUG "MTD point failed %d\n", ret)); + } +#endif + if (!flashbuf) { + /* For NAND it's quicker to read a whole eraseblock at a time, + apparently */ + if (jffs2_cleanmarker_oob(c)) + buf_size = c->sector_size; + else + buf_size = PAGE_SIZE; + + /* Respect kmalloc limitations */ + if (buf_size > 128*1024) + buf_size = 128*1024; + + D1(printk(KERN_DEBUG "Allocating readbuf of %d bytes\n", buf_size)); + flashbuf = kmalloc(buf_size, GFP_KERNEL); + if (!flashbuf) + return -ENOMEM; + } + + for (i=0; i<c->nr_blocks; i++) { + struct jffs2_eraseblock *jeb = &c->blocks[i]; + + ret = jffs2_scan_eraseblock(c, jeb, buf_size?flashbuf:(flashbuf+jeb->offset), buf_size); + + if (ret < 0) + goto out; + + ACCT_PARANOIA_CHECK(jeb); + + /* Now decide which list to put it on */ + switch(ret) { + case BLK_STATE_ALLFF: + /* + * Empty block. Since we can't be sure it + * was entirely erased, we just queue it for erase + * again. It will be marked as such when the erase + * is complete. Meanwhile we still count it as empty + * for later checks. + */ + empty_blocks++; + list_add(&jeb->list, &c->erase_pending_list); + c->nr_erasing_blocks++; + break; + + case BLK_STATE_CLEANMARKER: + /* Only a CLEANMARKER node is valid */ + if (!jeb->dirty_size) { + /* It's actually free */ + list_add(&jeb->list, &c->free_list); + c->nr_free_blocks++; + } else { + /* Dirt */ + D1(printk(KERN_DEBUG "Adding all-dirty block at 0x%08x to erase_pending_list\n", jeb->offset)); + list_add(&jeb->list, &c->erase_pending_list); + c->nr_erasing_blocks++; + } + break; + + case BLK_STATE_CLEAN: + /* Full (or almost full) of clean data. Clean list */ + list_add(&jeb->list, &c->clean_list); + break; + + case BLK_STATE_PARTDIRTY: + /* Some data, but not full. Dirty list. */ + /* We want to remember the block with most free space + and stick it in the 'nextblock' position to start writing to it. */ + if (jeb->free_size > min_free(c) && + (!c->nextblock || c->nextblock->free_size < jeb->free_size)) { + /* Better candidate for the next writes to go to */ + if (c->nextblock) { + c->nextblock->dirty_size += c->nextblock->free_size + c->nextblock->wasted_size; + c->dirty_size += c->nextblock->free_size + c->nextblock->wasted_size; + c->free_size -= c->nextblock->free_size; + c->wasted_size -= c->nextblock->wasted_size; + c->nextblock->free_size = c->nextblock->wasted_size = 0; + if (VERYDIRTY(c, c->nextblock->dirty_size)) { + list_add(&c->nextblock->list, &c->very_dirty_list); + } else { + list_add(&c->nextblock->list, &c->dirty_list); + } + } + c->nextblock = jeb; + } else { + jeb->dirty_size += jeb->free_size + jeb->wasted_size; + c->dirty_size += jeb->free_size + jeb->wasted_size; + c->free_size -= jeb->free_size; + c->wasted_size -= jeb->wasted_size; + jeb->free_size = jeb->wasted_size = 0; + if (VERYDIRTY(c, jeb->dirty_size)) { + list_add(&jeb->list, &c->very_dirty_list); + } else { + list_add(&jeb->list, &c->dirty_list); + } + } + break; + + case BLK_STATE_ALLDIRTY: + /* Nothing valid - not even a clean marker. Needs erasing. */ + /* For now we just put it on the erasing list. We'll start the erases later */ + D1(printk(KERN_NOTICE "JFFS2: Erase block at 0x%08x is not formatted. It will be erased\n", jeb->offset)); + list_add(&jeb->list, &c->erase_pending_list); + c->nr_erasing_blocks++; + break; + + case BLK_STATE_BADBLOCK: + D1(printk(KERN_NOTICE "JFFS2: Block at 0x%08x is bad\n", jeb->offset)); + list_add(&jeb->list, &c->bad_list); + c->bad_size += c->sector_size; + c->free_size -= c->sector_size; + bad_blocks++; + break; + default: + printk(KERN_WARNING "jffs2_scan_medium(): unknown block state\n"); + BUG(); + } + } + + /* Nextblock dirty is always seen as wasted, because we cannot recycle it now */ + if (c->nextblock && (c->nextblock->dirty_size)) { + c->nextblock->wasted_size += c->nextblock->dirty_size; + c->wasted_size += c->nextblock->dirty_size; + c->dirty_size -= c->nextblock->dirty_size; + c->nextblock->dirty_size = 0; + } +#if defined CONFIG_JFFS2_FS_NAND || defined CONFIG_JFFS2_FS_NOR_ECC + if (!jffs2_can_mark_obsolete(c) && c->nextblock && (c->nextblock->free_size & (c->wbuf_pagesize-1))) { + /* If we're going to start writing into a block which already + contains data, and the end of the data isn't page-aligned, + skip a little and align it. */ + + uint32_t skip = c->nextblock->free_size & (c->wbuf_pagesize-1); + + D1(printk(KERN_DEBUG "jffs2_scan_medium(): Skipping %d bytes in nextblock to ensure page alignment\n", + skip)); + c->nextblock->wasted_size += skip; + c->wasted_size += skip; + + c->nextblock->free_size -= skip; + c->free_size -= skip; + } +#endif + if (c->nr_erasing_blocks) { + if ( !c->used_size && ((c->nr_free_blocks+empty_blocks+bad_blocks)!= c->nr_blocks || bad_blocks == c->nr_blocks) ) { + printk(KERN_NOTICE "Cowardly refusing to erase blocks on filesystem with no valid JFFS2 nodes\n"); + printk(KERN_NOTICE "empty_blocks %d, bad_blocks %d, c->nr_blocks %d\n",empty_blocks,bad_blocks,c->nr_blocks); + ret = -EIO; + goto out; + } + jffs2_erase_pending_trigger(c); + } + ret = 0; + out: + if (buf_size) + kfree(flashbuf); +#ifndef __ECOS + else + c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size); +#endif + return ret; +} + +static int jffs2_fill_scan_buf (struct jffs2_sb_info *c, unsigned char *buf, + uint32_t ofs, uint32_t len) +{ + int ret; + size_t retlen; + + ret = jffs2_flash_read(c, ofs, len, &retlen, buf); + if (ret) { + D1(printk(KERN_WARNING "mtd->read(0x%x bytes from 0x%x) returned %d\n", len, ofs, ret)); + return ret; + } + if (retlen < len) { + D1(printk(KERN_WARNING "Read at 0x%x gave only 0x%zx bytes\n", ofs, retlen)); + return -EIO; + } + D2(printk(KERN_DEBUG "Read 0x%x bytes from 0x%08x into buf\n", len, ofs)); + D2(printk(KERN_DEBUG "000: %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n", + buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6], buf[7], buf[8], buf[9], buf[10], buf[11], buf[12], buf[13], buf[14], buf[15])); + return 0; +} + +static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, + unsigned char *buf, uint32_t buf_size) { + struct jffs2_unknown_node *node; + struct jffs2_unknown_node crcnode; + uint32_t ofs, prevofs; + uint32_t hdr_crc, buf_ofs, buf_len; + int err; + int noise = 0; +#ifdef CONFIG_JFFS2_FS_NAND + int cleanmarkerfound = 0; +#endif + + ofs = jeb->offset; + prevofs = jeb->offset - 1; + + D1(printk(KERN_DEBUG "jffs2_scan_eraseblock(): Scanning block at 0x%x\n", ofs)); + +#ifdef CONFIG_JFFS2_FS_NAND + if (jffs2_cleanmarker_oob(c)) { + int ret = jffs2_check_nand_cleanmarker(c, jeb); + D2(printk(KERN_NOTICE "jffs_check_nand_cleanmarker returned %d\n",ret)); + /* Even if it's not found, we still scan to see + if the block is empty. We use this information + to decide whether to erase it or not. */ + switch (ret) { + case 0: cleanmarkerfound = 1; break; + case 1: break; + case 2: return BLK_STATE_BADBLOCK; + case 3: return BLK_STATE_ALLDIRTY; /* Block has failed to erase min. once */ + default: return ret; + } + } +#endif + buf_ofs = jeb->offset; + + if (!buf_size) { + buf_len = c->sector_size; + } else { + buf_len = EMPTY_SCAN_SIZE; + err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len); + if (err) + return err; + } + + /* We temporarily use 'ofs' as a pointer into the buffer/jeb */ + ofs = 0; + + /* Scan only 4KiB of 0xFF before declaring it's empty */ + while(ofs < EMPTY_SCAN_SIZE && *(uint32_t *)(&buf[ofs]) == 0xFFFFFFFF) + ofs += 4; + + if (ofs == EMPTY_SCAN_SIZE) { +#ifdef CONFIG_JFFS2_FS_NAND + if (jffs2_cleanmarker_oob(c)) { + /* scan oob, take care of cleanmarker */ + int ret = jffs2_check_oob_empty(c, jeb, cleanmarkerfound); + D2(printk(KERN_NOTICE "jffs2_check_oob_empty returned %d\n",ret)); + switch (ret) { + case 0: return cleanmarkerfound ? BLK_STATE_CLEANMARKER : BLK_STATE_ALLFF; + case 1: return BLK_STATE_ALLDIRTY; + default: return ret; + } + } +#endif + D1(printk(KERN_DEBUG "Block at 0x%08x is empty (erased)\n", jeb->offset)); + return BLK_STATE_ALLFF; /* OK to erase if all blocks are like this */ + } + if (ofs) { + D1(printk(KERN_DEBUG "Free space at %08x ends at %08x\n", jeb->offset, + jeb->offset + ofs)); + DIRTY_SPACE(ofs); + } + + /* Now ofs is a complete physical flash offset as it always was... */ + ofs += jeb->offset; + + noise = 10; + +scan_more: + while(ofs < jeb->offset + c->sector_size) { + + D1(ACCT_PARANOIA_CHECK(jeb)); + + cond_resched(); + + if (ofs & 3) { + printk(KERN_WARNING "Eep. ofs 0x%08x not word-aligned!\n", ofs); + ofs = PAD(ofs); + continue; + } + if (ofs == prevofs) { + printk(KERN_WARNING "ofs 0x%08x has already been seen. Skipping\n", ofs); + DIRTY_SPACE(4); + ofs += 4; + continue; + } + prevofs = ofs; + + if (jeb->offset + c->sector_size < ofs + sizeof(*node)) { + D1(printk(KERN_DEBUG "Fewer than %zd bytes left to end of block. (%x+%x<%x+%zx) Not reading\n", sizeof(struct jffs2_unknown_node), + jeb->offset, c->sector_size, ofs, sizeof(*node))); + DIRTY_SPACE((jeb->offset + c->sector_size)-ofs); + break; + } + + if (buf_ofs + buf_len < ofs + sizeof(*node)) { + buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); + D1(printk(KERN_DEBUG "Fewer than %zd bytes (node header) left to end of buf. Reading 0x%x at 0x%08x\n", + sizeof(struct jffs2_unknown_node), buf_len, ofs)); + err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); + if (err) + return err; + buf_ofs = ofs; + } + + node = (struct jffs2_unknown_node *)&buf[ofs-buf_ofs]; + + if (*(uint32_t *)(&buf[ofs-buf_ofs]) == 0xffffffff) { + uint32_t inbuf_ofs; + uint32_t empty_start; + + empty_start = ofs; + ofs += 4; + + D1(printk(KERN_DEBUG "Found empty flash at 0x%08x\n", ofs)); + more_empty: + inbuf_ofs = ofs - buf_ofs; + while (inbuf_ofs < buf_len) { + if (*(uint32_t *)(&buf[inbuf_ofs]) != 0xffffffff) { + printk(KERN_WARNING "Empty flash at 0x%08x ends at 0x%08x\n", + empty_start, ofs); + DIRTY_SPACE(ofs-empty_start); + goto scan_more; + } + + inbuf_ofs+=4; + ofs += 4; + } + /* Ran off end. */ + D1(printk(KERN_DEBUG "Empty flash to end of buffer at 0x%08x\n", ofs)); + + /* If we're only checking the beginning of a block with a cleanmarker, + bail now */ + if (buf_ofs == jeb->offset && jeb->used_size == PAD(c->cleanmarker_size) && + c->cleanmarker_size && !jeb->dirty_size && !jeb->first_node->next_in_ino) { + D1(printk(KERN_DEBUG "%d bytes at start of block seems clean... assuming all clean\n", EMPTY_SCAN_SIZE)); + return BLK_STATE_CLEANMARKER; + } + + /* See how much more there is to read in this eraseblock... */ + buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); + if (!buf_len) { + /* No more to read. Break out of main loop without marking + this range of empty space as dirty (because it's not) */ + D1(printk(KERN_DEBUG "Empty flash at %08x runs to end of block. Treating as free_space\n", + empty_start)); + break; + } + D1(printk(KERN_DEBUG "Reading another 0x%x at 0x%08x\n", buf_len, ofs)); + err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); + if (err) + return err; + buf_ofs = ofs; + goto more_empty; + } + + if (ofs == jeb->offset && je16_to_cpu(node->magic) == KSAMTIB_CIGAM_2SFFJ) { + printk(KERN_WARNING "Magic bitmask is backwards at offset 0x%08x. Wrong endian filesystem?\n", ofs); + DIRTY_SPACE(4); + ofs += 4; + continue; + } + if (je16_to_cpu(node->magic) == JFFS2_DIRTY_BITMASK) { + D1(printk(KERN_DEBUG "Dirty bitmask at 0x%08x\n", ofs)); + DIRTY_SPACE(4); + ofs += 4; + continue; + } + if (je16_to_cpu(node->magic) == JFFS2_OLD_MAGIC_BITMASK) { + printk(KERN_WARNING "Old JFFS2 bitmask found at 0x%08x\n", ofs); + printk(KERN_WARNING "You cannot use older JFFS2 filesystems with newer kernels\n"); + DIRTY_SPACE(4); + ofs += 4; + continue; + } + if (je16_to_cpu(node->magic) != JFFS2_MAGIC_BITMASK) { + /* OK. We're out of possibilities. Whinge and move on */ + noisy_printk(&noise, "jffs2_scan_eraseblock(): Magic bitmask 0x%04x not found at 0x%08x: 0x%04x instead\n", + JFFS2_MAGIC_BITMASK, ofs, + je16_to_cpu(node->magic)); + DIRTY_SPACE(4); + ofs += 4; + continue; + } + /* We seem to have a node of sorts. Check the CRC */ + crcnode.magic = node->magic; + crcnode.nodetype = cpu_to_je16( je16_to_cpu(node->nodetype) | JFFS2_NODE_ACCURATE); + crcnode.totlen = node->totlen; + hdr_crc = crc32(0, &crcnode, sizeof(crcnode)-4); + + if (hdr_crc != je32_to_cpu(node->hdr_crc)) { + noisy_printk(&noise, "jffs2_scan_eraseblock(): Node at 0x%08x {0x%04x, 0x%04x, 0x%08x) has invalid CRC 0x%08x (calculated 0x%08x)\n", + ofs, je16_to_cpu(node->magic), + je16_to_cpu(node->nodetype), + je32_to_cpu(node->totlen), + je32_to_cpu(node->hdr_crc), + hdr_crc); + DIRTY_SPACE(4); + ofs += 4; + continue; + } + + if (ofs + je32_to_cpu(node->totlen) > + jeb->offset + c->sector_size) { + /* Eep. Node goes over the end of the erase block. */ + printk(KERN_WARNING "Node at 0x%08x with length 0x%08x would run over the end of the erase block\n", + ofs, je32_to_cpu(node->totlen)); + printk(KERN_WARNING "Perhaps the file system was created with the wrong erase size?\n"); + DIRTY_SPACE(4); + ofs += 4; + continue; + } + + if (!(je16_to_cpu(node->nodetype) & JFFS2_NODE_ACCURATE)) { + /* Wheee. This is an obsoleted node */ + D2(printk(KERN_DEBUG "Node at 0x%08x is obsolete. Skipping\n", ofs)); + DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); + ofs += PAD(je32_to_cpu(node->totlen)); + continue; + } + + switch(je16_to_cpu(node->nodetype)) { + case JFFS2_NODETYPE_INODE: + if (buf_ofs + buf_len < ofs + sizeof(struct jffs2_raw_inode)) { + buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); + D1(printk(KERN_DEBUG "Fewer than %zd bytes (inode node) left to end of buf. Reading 0x%x at 0x%08x\n", + sizeof(struct jffs2_raw_inode), buf_len, ofs)); + err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); + if (err) + return err; + buf_ofs = ofs; + node = (void *)buf; + } + err = jffs2_scan_inode_node(c, jeb, (void *)node, ofs); + if (err) return err; + ofs += PAD(je32_to_cpu(node->totlen)); + break; + + case JFFS2_NODETYPE_DIRENT: + if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) { + buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); + D1(printk(KERN_DEBUG "Fewer than %d bytes (dirent node) left to end of buf. Reading 0x%x at 0x%08x\n", + je32_to_cpu(node->totlen), buf_len, ofs)); + err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); + if (err) + return err; + buf_ofs = ofs; + node = (void *)buf; + } + err = jffs2_scan_dirent_node(c, jeb, (void *)node, ofs); + if (err) return err; + ofs += PAD(je32_to_cpu(node->totlen)); + break; + + case JFFS2_NODETYPE_CLEANMARKER: + D1(printk(KERN_DEBUG "CLEANMARKER node found at 0x%08x\n", ofs)); + if (je32_to_cpu(node->totlen) != c->cleanmarker_size) { + printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x has totlen 0x%x != normal 0x%x\n", + ofs, je32_to_cpu(node->totlen), c->cleanmarker_size); + DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node))); + ofs += PAD(sizeof(struct jffs2_unknown_node)); + } else if (jeb->first_node) { + printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x, not first node in block (0x%08x)\n", ofs, jeb->offset); + DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node))); + ofs += PAD(sizeof(struct jffs2_unknown_node)); + } else { + struct jffs2_raw_node_ref *marker_ref = jffs2_alloc_raw_node_ref(); + if (!marker_ref) { + printk(KERN_NOTICE "Failed to allocate node ref for clean marker\n"); + return -ENOMEM; + } + marker_ref->next_in_ino = NULL; + marker_ref->next_phys = NULL; + marker_ref->flash_offset = ofs | REF_NORMAL; + marker_ref->__totlen = c->cleanmarker_size; + jeb->first_node = jeb->last_node = marker_ref; + + USED_SPACE(PAD(c->cleanmarker_size)); + ofs += PAD(c->cleanmarker_size); + } + break; + + case JFFS2_NODETYPE_PADDING: + DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); + ofs += PAD(je32_to_cpu(node->totlen)); + break; + + default: + switch (je16_to_cpu(node->nodetype) & JFFS2_COMPAT_MASK) { + case JFFS2_FEATURE_ROCOMPAT: + printk(KERN_NOTICE "Read-only compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs); + c->flags |= JFFS2_SB_FLAG_RO; + if (!(jffs2_is_readonly(c))) + return -EROFS; + DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); + ofs += PAD(je32_to_cpu(node->totlen)); + break; + + case JFFS2_FEATURE_INCOMPAT: + printk(KERN_NOTICE "Incompatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs); + return -EINVAL; + + case JFFS2_FEATURE_RWCOMPAT_DELETE: + D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs)); + DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); + ofs += PAD(je32_to_cpu(node->totlen)); + break; + + case JFFS2_FEATURE_RWCOMPAT_COPY: + D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs)); + USED_SPACE(PAD(je32_to_cpu(node->totlen))); + ofs += PAD(je32_to_cpu(node->totlen)); + break; + } + } + } + + + D1(printk(KERN_DEBUG "Block at 0x%08x: free 0x%08x, dirty 0x%08x, unchecked 0x%08x, used 0x%08x\n", jeb->offset, + jeb->free_size, jeb->dirty_size, jeb->unchecked_size, jeb->used_size)); + + /* mark_node_obsolete can add to wasted !! */ + if (jeb->wasted_size) { + jeb->dirty_size += jeb->wasted_size; + c->dirty_size += jeb->wasted_size; + c->wasted_size -= jeb->wasted_size; + jeb->wasted_size = 0; + } + + if ((jeb->used_size + jeb->unchecked_size) == PAD(c->cleanmarker_size) && !jeb->dirty_size + && (!jeb->first_node || !jeb->first_node->next_in_ino) ) + return BLK_STATE_CLEANMARKER; + + /* move blocks with max 4 byte dirty space to cleanlist */ + else if (!ISDIRTY(c->sector_size - (jeb->used_size + jeb->unchecked_size))) { + c->dirty_size -= jeb->dirty_size; + c->wasted_size += jeb->dirty_size; + jeb->wasted_size += jeb->dirty_size; + jeb->dirty_size = 0; + return BLK_STATE_CLEAN; + } else if (jeb->used_size || jeb->unchecked_size) + return BLK_STATE_PARTDIRTY; + else + return BLK_STATE_ALLDIRTY; +} + +static struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino) +{ + struct jffs2_inode_cache *ic; + + ic = jffs2_get_ino_cache(c, ino); + if (ic) + return ic; + + if (ino > c->highest_ino) + c->highest_ino = ino; + + ic = jffs2_alloc_inode_cache(); + if (!ic) { + printk(KERN_NOTICE "jffs2_scan_make_inode_cache(): allocation of inode cache failed\n"); + return NULL; + } + memset(ic, 0, sizeof(*ic)); + + ic->ino = ino; + ic->nodes = (void *)ic; + jffs2_add_ino_cache(c, ic); + if (ino == 1) + ic->nlink = 1; + return ic; +} + +static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, + struct jffs2_raw_inode *ri, uint32_t ofs) +{ + struct jffs2_raw_node_ref *raw; + struct jffs2_inode_cache *ic; + uint32_t ino = je32_to_cpu(ri->ino); + + D1(printk(KERN_DEBUG "jffs2_scan_inode_node(): Node at 0x%08x\n", ofs)); + + /* We do very little here now. Just check the ino# to which we should attribute + this node; we can do all the CRC checking etc. later. There's a tradeoff here -- + we used to scan the flash once only, reading everything we want from it into + memory, then building all our in-core data structures and freeing the extra + information. Now we allow the first part of the mount to complete a lot quicker, + but we have to go _back_ to the flash in order to finish the CRC checking, etc. + Which means that the _full_ amount of time to get to proper write mode with GC + operational may actually be _longer_ than before. Sucks to be me. */ + + raw = jffs2_alloc_raw_node_ref(); + if (!raw) { + printk(KERN_NOTICE "jffs2_scan_inode_node(): allocation of node reference failed\n"); + return -ENOMEM; + } + + ic = jffs2_get_ino_cache(c, ino); + if (!ic) { + /* Inocache get failed. Either we read a bogus ino# or it's just genuinely the + first node we found for this inode. Do a CRC check to protect against the former + case */ + uint32_t crc = crc32(0, ri, sizeof(*ri)-8); + + if (crc != je32_to_cpu(ri->node_crc)) { + printk(KERN_NOTICE "jffs2_scan_inode_node(): CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", + ofs, je32_to_cpu(ri->node_crc), crc); + /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */ + DIRTY_SPACE(PAD(je32_to_cpu(ri->totlen))); + jffs2_free_raw_node_ref(raw); + return 0; + } + ic = jffs2_scan_make_ino_cache(c, ino); + if (!ic) { + jffs2_free_raw_node_ref(raw); + return -ENOMEM; + } + } + + /* Wheee. It worked */ + + raw->flash_offset = ofs | REF_UNCHECKED; + raw->__totlen = PAD(je32_to_cpu(ri->totlen)); + raw->next_phys = NULL; + raw->next_in_ino = ic->nodes; + + ic->nodes = raw; + if (!jeb->first_node) + jeb->first_node = raw; + if (jeb->last_node) + jeb->last_node->next_phys = raw; + jeb->last_node = raw; + + D1(printk(KERN_DEBUG "Node is ino #%u, version %d. Range 0x%x-0x%x\n", + je32_to_cpu(ri->ino), je32_to_cpu(ri->version), + je32_to_cpu(ri->offset), + je32_to_cpu(ri->offset)+je32_to_cpu(ri->dsize))); + + pseudo_random += je32_to_cpu(ri->version); + + UNCHECKED_SPACE(PAD(je32_to_cpu(ri->totlen))); + return 0; +} + +static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, + struct jffs2_raw_dirent *rd, uint32_t ofs) +{ + struct jffs2_raw_node_ref *raw; + struct jffs2_full_dirent *fd; + struct jffs2_inode_cache *ic; + uint32_t crc; + + D1(printk(KERN_DEBUG "jffs2_scan_dirent_node(): Node at 0x%08x\n", ofs)); + + /* We don't get here unless the node is still valid, so we don't have to + mask in the ACCURATE bit any more. */ + crc = crc32(0, rd, sizeof(*rd)-8); + + if (crc != je32_to_cpu(rd->node_crc)) { + printk(KERN_NOTICE "jffs2_scan_dirent_node(): Node CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", + ofs, je32_to_cpu(rd->node_crc), crc); + /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */ + DIRTY_SPACE(PAD(je32_to_cpu(rd->totlen))); + return 0; + } + + pseudo_random += je32_to_cpu(rd->version); + + fd = jffs2_alloc_full_dirent(rd->nsize+1); + if (!fd) { + return -ENOMEM; + } + memcpy(&fd->name, rd->name, rd->nsize); + fd->name[rd->nsize] = 0; + + crc = crc32(0, fd->name, rd->nsize); + if (crc != je32_to_cpu(rd->name_crc)) { + printk(KERN_NOTICE "jffs2_scan_dirent_node(): Name CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", + ofs, je32_to_cpu(rd->name_crc), crc); + D1(printk(KERN_NOTICE "Name for which CRC failed is (now) '%s', ino #%d\n", fd->name, je32_to_cpu(rd->ino))); + jffs2_free_full_dirent(fd); + /* FIXME: Why do we believe totlen? */ + /* We believe totlen because the CRC on the node _header_ was OK, just the name failed. */ + DIRTY_SPACE(PAD(je32_to_cpu(rd->totlen))); + return 0; + } + raw = jffs2_alloc_raw_node_ref(); + if (!raw) { + jffs2_free_full_dirent(fd); + printk(KERN_NOTICE "jffs2_scan_dirent_node(): allocation of node reference failed\n"); + return -ENOMEM; + } + ic = jffs2_scan_make_ino_cache(c, je32_to_cpu(rd->pino)); + if (!ic) { + jffs2_free_full_dirent(fd); + jffs2_free_raw_node_ref(raw); + return -ENOMEM; + } + + raw->__totlen = PAD(je32_to_cpu(rd->totlen)); + raw->flash_offset = ofs | REF_PRISTINE; + raw->next_phys = NULL; + raw->next_in_ino = ic->nodes; + ic->nodes = raw; + if (!jeb->first_node) + jeb->first_node = raw; + if (jeb->last_node) + jeb->last_node->next_phys = raw; + jeb->last_node = raw; + + fd->raw = raw; + fd->next = NULL; + fd->version = je32_to_cpu(rd->version); + fd->ino = je32_to_cpu(rd->ino); + fd->nhash = full_name_hash(fd->name, rd->nsize); + fd->type = rd->type; + USED_SPACE(PAD(je32_to_cpu(rd->totlen))); + jffs2_add_fd_to_list(c, fd, &ic->scan_dents); + + return 0; +} + +static int count_list(struct list_head *l) +{ + uint32_t count = 0; + struct list_head *tmp; + + list_for_each(tmp, l) { + count++; + } + return count; +} + +/* Note: This breaks if list_empty(head). I don't care. You + might, if you copy this code and use it elsewhere :) */ +static void rotate_list(struct list_head *head, uint32_t count) +{ + struct list_head *n = head->next; + + list_del(head); + while(count--) { + n = n->next; + } + list_add(head, n); +} + +void jffs2_rotate_lists(struct jffs2_sb_info *c) +{ + uint32_t x; + uint32_t rotateby; + + x = count_list(&c->clean_list); + if (x) { + rotateby = pseudo_random % x; + D1(printk(KERN_DEBUG "Rotating clean_list by %d\n", rotateby)); + + rotate_list((&c->clean_list), rotateby); + + D1(printk(KERN_DEBUG "Erase block at front of clean_list is at %08x\n", + list_entry(c->clean_list.next, struct jffs2_eraseblock, list)->offset)); + } else { + D1(printk(KERN_DEBUG "Not rotating empty clean_list\n")); + } + + x = count_list(&c->very_dirty_list); + if (x) { + rotateby = pseudo_random % x; + D1(printk(KERN_DEBUG "Rotating very_dirty_list by %d\n", rotateby)); + + rotate_list((&c->very_dirty_list), rotateby); + + D1(printk(KERN_DEBUG "Erase block at front of very_dirty_list is at %08x\n", + list_entry(c->very_dirty_list.next, struct jffs2_eraseblock, list)->offset)); + } else { + D1(printk(KERN_DEBUG "Not rotating empty very_dirty_list\n")); + } + + x = count_list(&c->dirty_list); + if (x) { + rotateby = pseudo_random % x; + D1(printk(KERN_DEBUG "Rotating dirty_list by %d\n", rotateby)); + + rotate_list((&c->dirty_list), rotateby); + + D1(printk(KERN_DEBUG "Erase block at front of dirty_list is at %08x\n", + list_entry(c->dirty_list.next, struct jffs2_eraseblock, list)->offset)); + } else { + D1(printk(KERN_DEBUG "Not rotating empty dirty_list\n")); + } + + x = count_list(&c->erasable_list); + if (x) { + rotateby = pseudo_random % x; + D1(printk(KERN_DEBUG "Rotating erasable_list by %d\n", rotateby)); + + rotate_list((&c->erasable_list), rotateby); + + D1(printk(KERN_DEBUG "Erase block at front of erasable_list is at %08x\n", + list_entry(c->erasable_list.next, struct jffs2_eraseblock, list)->offset)); + } else { + D1(printk(KERN_DEBUG "Not rotating empty erasable_list\n")); + } + + if (c->nr_erasing_blocks) { + rotateby = pseudo_random % c->nr_erasing_blocks; + D1(printk(KERN_DEBUG "Rotating erase_pending_list by %d\n", rotateby)); + + rotate_list((&c->erase_pending_list), rotateby); + + D1(printk(KERN_DEBUG "Erase block at front of erase_pending_list is at %08x\n", + list_entry(c->erase_pending_list.next, struct jffs2_eraseblock, list)->offset)); + } else { + D1(printk(KERN_DEBUG "Not rotating empty erase_pending_list\n")); + } + + if (c->nr_free_blocks) { + rotateby = pseudo_random % c->nr_free_blocks; + D1(printk(KERN_DEBUG "Rotating free_list by %d\n", rotateby)); + + rotate_list((&c->free_list), rotateby); + + D1(printk(KERN_DEBUG "Erase block at front of free_list is at %08x\n", + list_entry(c->free_list.next, struct jffs2_eraseblock, list)->offset)); + } else { + D1(printk(KERN_DEBUG "Not rotating empty free_list\n")); + } +} |