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-rw-r--r--fs/jffs/intrep.c3449
1 files changed, 0 insertions, 3449 deletions
diff --git a/fs/jffs/intrep.c b/fs/jffs/intrep.c
deleted file mode 100644
index 6dd18911b44..00000000000
--- a/fs/jffs/intrep.c
+++ /dev/null
@@ -1,3449 +0,0 @@
-/*
- * JFFS -- Journaling Flash File System, Linux implementation.
- *
- * Copyright (C) 1999, 2000 Axis Communications, Inc.
- *
- * Created by Finn Hakansson <finn@axis.com>.
- *
- * This is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * $Id: intrep.c,v 1.102 2001/09/23 23:28:36 dwmw2 Exp $
- *
- * Ported to Linux 2.3.x and MTD:
- * Copyright (C) 2000 Alexander Larsson (alex@cendio.se), Cendio Systems AB
- *
- */
-
-/* This file contains the code for the internal structure of the
- Journaling Flash File System, JFFS. */
-
-/*
- * Todo list:
- *
- * memcpy_to_flash() and memcpy_from_flash() functions.
- *
- * Implementation of hard links.
- *
- * Organize the source code in a better way. Against the VFS we could
- * have jffs_ext.c, and against the block device jffs_int.c.
- * A better file-internal organization too.
- *
- * A better checksum algorithm.
- *
- * Consider endianness stuff. ntohl() etc.
- *
- * Are we handling the atime, mtime, ctime members of the inode right?
- *
- * Remove some duplicated code. Take a look at jffs_write_node() and
- * jffs_rewrite_data() for instance.
- *
- * Implement more meaning of the nlink member in various data structures.
- * nlink could be used in conjunction with hard links for instance.
- *
- * Better memory management. Allocate data structures in larger chunks
- * if possible.
- *
- * If too much meta data is stored, a garbage collect should be issued.
- * We have experienced problems with too much meta data with for instance
- * log files.
- *
- * Improve the calls to jffs_ioctl(). We would like to retrieve more
- * information to be able to debug (or to supervise) JFFS during run-time.
- *
- */
-
-#include <linux/types.h>
-#include <linux/slab.h>
-#include <linux/jffs.h>
-#include <linux/fs.h>
-#include <linux/stat.h>
-#include <linux/pagemap.h>
-#include <linux/mutex.h>
-#include <asm/byteorder.h>
-#include <linux/smp_lock.h>
-#include <linux/time.h>
-#include <linux/ctype.h>
-#include <linux/freezer.h>
-
-#include "intrep.h"
-#include "jffs_fm.h"
-
-long no_jffs_node = 0;
-static long no_jffs_file = 0;
-#if defined(JFFS_MEMORY_DEBUG) && JFFS_MEMORY_DEBUG
-long no_jffs_control = 0;
-long no_jffs_raw_inode = 0;
-long no_jffs_node_ref = 0;
-long no_jffs_fm = 0;
-long no_jffs_fmcontrol = 0;
-long no_hash = 0;
-long no_name = 0;
-#endif
-
-static int jffs_scan_flash(struct jffs_control *c);
-static int jffs_update_file(struct jffs_file *f, struct jffs_node *node);
-static int jffs_build_file(struct jffs_file *f);
-static int jffs_free_file(struct jffs_file *f);
-static int jffs_free_node_list(struct jffs_file *f);
-static int jffs_garbage_collect_now(struct jffs_control *c);
-static int jffs_insert_file_into_hash(struct jffs_file *f);
-static int jffs_remove_redundant_nodes(struct jffs_file *f);
-
-/* Is there enough space on the flash? */
-static inline int JFFS_ENOUGH_SPACE(struct jffs_control *c, __u32 space)
-{
- struct jffs_fmcontrol *fmc = c->fmc;
-
- while (1) {
- if ((fmc->flash_size - (fmc->used_size + fmc->dirty_size))
- >= fmc->min_free_size + space) {
- return 1;
- }
- if (fmc->dirty_size < fmc->sector_size)
- return 0;
-
- if (jffs_garbage_collect_now(c)) {
- D1(printk("JFFS_ENOUGH_SPACE: jffs_garbage_collect_now() failed.\n"));
- return 0;
- }
- }
-}
-
-#if CONFIG_JFFS_FS_VERBOSE > 0
-static __u8
-flash_read_u8(struct mtd_info *mtd, loff_t from)
-{
- size_t retlen;
- __u8 ret;
- int res;
-
- res = MTD_READ(mtd, from, 1, &retlen, &ret);
- if (retlen != 1) {
- printk("Didn't read a byte in flash_read_u8(). Returned %d\n", res);
- return 0;
- }
-
- return ret;
-}
-
-static void
-jffs_hexdump(struct mtd_info *mtd, loff_t pos, int size)
-{
- char line[16];
- int j = 0;
-
- while (size > 0) {
- int i;
-
- printk("%ld:", (long) pos);
- for (j = 0; j < 16; j++) {
- line[j] = flash_read_u8(mtd, pos++);
- }
- for (i = 0; i < j; i++) {
- if (!(i & 1)) {
- printk(" %.2x", line[i] & 0xff);
- }
- else {
- printk("%.2x", line[i] & 0xff);
- }
- }
-
- /* Print empty space */
- for (; i < 16; i++) {
- if (!(i & 1)) {
- printk(" ");
- }
- else {
- printk(" ");
- }
- }
- printk(" ");
-
- for (i = 0; i < j; i++) {
- if (isgraph(line[i])) {
- printk("%c", line[i]);
- }
- else {
- printk(".");
- }
- }
- printk("\n");
- size -= 16;
- }
-}
-
-/* Print the contents of a node. */
-static void
-jffs_print_node(struct jffs_node *n)
-{
- D(printk("jffs_node: 0x%p\n", n));
- D(printk("{\n"));
- D(printk(" 0x%08x, /* version */\n", n->version));
- D(printk(" 0x%08x, /* data_offset */\n", n->data_offset));
- D(printk(" 0x%08x, /* data_size */\n", n->data_size));
- D(printk(" 0x%08x, /* removed_size */\n", n->removed_size));
- D(printk(" 0x%08x, /* fm_offset */\n", n->fm_offset));
- D(printk(" 0x%02x, /* name_size */\n", n->name_size));
- D(printk(" 0x%p, /* fm, fm->offset: %u */\n",
- n->fm, (n->fm ? n->fm->offset : 0)));
- D(printk(" 0x%p, /* version_prev */\n", n->version_prev));
- D(printk(" 0x%p, /* version_next */\n", n->version_next));
- D(printk(" 0x%p, /* range_prev */\n", n->range_prev));
- D(printk(" 0x%p, /* range_next */\n", n->range_next));
- D(printk("}\n"));
-}
-
-#endif
-
-/* Print the contents of a raw inode. */
-static void
-jffs_print_raw_inode(struct jffs_raw_inode *raw_inode)
-{
- D(printk("jffs_raw_inode: inode number: %u\n", raw_inode->ino));
- D(printk("{\n"));
- D(printk(" 0x%08x, /* magic */\n", raw_inode->magic));
- D(printk(" 0x%08x, /* ino */\n", raw_inode->ino));
- D(printk(" 0x%08x, /* pino */\n", raw_inode->pino));
- D(printk(" 0x%08x, /* version */\n", raw_inode->version));
- D(printk(" 0x%08x, /* mode */\n", raw_inode->mode));
- D(printk(" 0x%04x, /* uid */\n", raw_inode->uid));
- D(printk(" 0x%04x, /* gid */\n", raw_inode->gid));
- D(printk(" 0x%08x, /* atime */\n", raw_inode->atime));
- D(printk(" 0x%08x, /* mtime */\n", raw_inode->mtime));
- D(printk(" 0x%08x, /* ctime */\n", raw_inode->ctime));
- D(printk(" 0x%08x, /* offset */\n", raw_inode->offset));
- D(printk(" 0x%08x, /* dsize */\n", raw_inode->dsize));
- D(printk(" 0x%08x, /* rsize */\n", raw_inode->rsize));
- D(printk(" 0x%02x, /* nsize */\n", raw_inode->nsize));
- D(printk(" 0x%02x, /* nlink */\n", raw_inode->nlink));
- D(printk(" 0x%02x, /* spare */\n",
- raw_inode->spare));
- D(printk(" %u, /* rename */\n",
- raw_inode->rename));
- D(printk(" %u, /* deleted */\n",
- raw_inode->deleted));
- D(printk(" 0x%02x, /* accurate */\n",
- raw_inode->accurate));
- D(printk(" 0x%08x, /* dchksum */\n", raw_inode->dchksum));
- D(printk(" 0x%04x, /* nchksum */\n", raw_inode->nchksum));
- D(printk(" 0x%04x, /* chksum */\n", raw_inode->chksum));
- D(printk("}\n"));
-}
-
-#define flash_safe_acquire(arg)
-#define flash_safe_release(arg)
-
-
-static int
-flash_safe_read(struct mtd_info *mtd, loff_t from,
- u_char *buf, size_t count)
-{
- size_t retlen;
- int res;
-
- D3(printk(KERN_NOTICE "flash_safe_read(%p, %08x, %p, %08x)\n",
- mtd, (unsigned int) from, buf, count));
-
- res = mtd->read(mtd, from, count, &retlen, buf);
- if (retlen != count) {
- panic("Didn't read all bytes in flash_safe_read(). Returned %d\n", res);
- }
- return res?res:retlen;
-}
-
-
-static __u32
-flash_read_u32(struct mtd_info *mtd, loff_t from)
-{
- size_t retlen;
- __u32 ret;
- int res;
-
- res = mtd->read(mtd, from, 4, &retlen, (unsigned char *)&ret);
- if (retlen != 4) {
- printk("Didn't read all bytes in flash_read_u32(). Returned %d\n", res);
- return 0;
- }
-
- return ret;
-}
-
-
-static int
-flash_safe_write(struct mtd_info *mtd, loff_t to,
- const u_char *buf, size_t count)
-{
- size_t retlen;
- int res;
-
- D3(printk(KERN_NOTICE "flash_safe_write(%p, %08x, %p, %08x)\n",
- mtd, (unsigned int) to, buf, count));
-
- res = mtd->write(mtd, to, count, &retlen, buf);
- if (retlen != count) {
- printk("Didn't write all bytes in flash_safe_write(). Returned %d\n", res);
- }
- return res?res:retlen;
-}
-
-
-static int
-flash_safe_writev(struct mtd_info *mtd, const struct kvec *vecs,
- unsigned long iovec_cnt, loff_t to)
-{
- size_t retlen, retlen_a;
- int i;
- int res;
-
- D3(printk(KERN_NOTICE "flash_safe_writev(%p, %08x, %p)\n",
- mtd, (unsigned int) to, vecs));
-
- if (mtd->writev) {
- res = mtd->writev(mtd, vecs, iovec_cnt, to, &retlen);
- return res ? res : retlen;
- }
- /* Not implemented writev. Repeatedly use write - on the not so
- unreasonable assumption that the mtd driver doesn't care how
- many write cycles we use. */
- res=0;
- retlen=0;
-
- for (i=0; !res && i<iovec_cnt; i++) {
- res = mtd->write(mtd, to, vecs[i].iov_len, &retlen_a,
- vecs[i].iov_base);
- if (retlen_a != vecs[i].iov_len) {
- printk("Didn't write all bytes in flash_safe_writev(). Returned %d\n", res);
- if (i != iovec_cnt-1)
- return -EIO;
- }
- /* If res is non-zero, retlen_a is undefined, but we don't
- care because in that case it's not going to be
- returned anyway.
- */
- to += retlen_a;
- retlen += retlen_a;
- }
- return res?res:retlen;
-}
-
-
-static int
-flash_memset(struct mtd_info *mtd, loff_t to,
- const u_char c, size_t size)
-{
- static unsigned char pattern[64];
- int i;
-
- /* fill up pattern */
-
- for(i = 0; i < 64; i++)
- pattern[i] = c;
-
- /* write as many 64-byte chunks as we can */
-
- while (size >= 64) {
- flash_safe_write(mtd, to, pattern, 64);
- size -= 64;
- to += 64;
- }
-
- /* and the rest */
-
- if(size)
- flash_safe_write(mtd, to, pattern, size);
-
- return size;
-}
-
-
-static void
-intrep_erase_callback(struct erase_info *done)
-{
- wait_queue_head_t *wait_q;
-
- wait_q = (wait_queue_head_t *)done->priv;
-
- wake_up(wait_q);
-}
-
-
-static int
-flash_erase_region(struct mtd_info *mtd, loff_t start,
- size_t size)
-{
- struct erase_info *erase;
- DECLARE_WAITQUEUE(wait, current);
- wait_queue_head_t wait_q;
-
- erase = kmalloc(sizeof(struct erase_info), GFP_KERNEL);
- if (!erase)
- return -ENOMEM;
-
- init_waitqueue_head(&wait_q);
-
- erase->mtd = mtd;
- erase->callback = intrep_erase_callback;
- erase->addr = start;
- erase->len = size;
- erase->priv = (u_long)&wait_q;
-
- /* FIXME: Use TASK_INTERRUPTIBLE and deal with being interrupted */
- set_current_state(TASK_UNINTERRUPTIBLE);
- add_wait_queue(&wait_q, &wait);
-
- if (mtd->erase(mtd, erase) < 0) {
- set_current_state(TASK_RUNNING);
- remove_wait_queue(&wait_q, &wait);
- kfree(erase);
-
- printk(KERN_WARNING "flash: erase of region [0x%lx, 0x%lx] "
- "totally failed\n", (long)start, (long)start + size);
-
- return -1;
- }
-
- schedule(); /* Wait for flash to finish. */
- remove_wait_queue(&wait_q, &wait);
-
- kfree(erase);
-
- return 0;
-}
-
-/* This routine calculates checksums in JFFS. */
-static __u32
-jffs_checksum(const void *data, int size)
-{
- __u32 sum = 0;
- __u8 *ptr = (__u8 *)data;
- while (size-- > 0) {
- sum += *ptr++;
- }
- D3(printk(", result: 0x%08x\n", sum));
- return sum;
-}
-
-
-static int
-jffs_checksum_flash(struct mtd_info *mtd, loff_t start, int size, __u32 *result)
-{
- __u32 sum = 0;
- loff_t ptr = start;
- __u8 *read_buf;
- int i, length;
-
- /* Allocate read buffer */
- read_buf = kmalloc(sizeof(__u8) * 4096, GFP_KERNEL);
- if (!read_buf) {
- printk(KERN_NOTICE "kmalloc failed in jffs_checksum_flash()\n");
- return -ENOMEM;
- }
- /* Loop until checksum done */
- while (size) {
- /* Get amount of data to read */
- if (size < 4096)
- length = size;
- else
- length = 4096;
-
- /* Perform flash read */
- D3(printk(KERN_NOTICE "jffs_checksum_flash\n"));
- flash_safe_read(mtd, ptr, &read_buf[0], length);
-
- /* Compute checksum */
- for (i=0; i < length ; i++)
- sum += read_buf[i];
-
- /* Update pointer and size */
- size -= length;
- ptr += length;
- }
-
- /* Free read buffer */
- kfree(read_buf);
-
- /* Return result */
- D3(printk("checksum result: 0x%08x\n", sum));
- *result = sum;
- return 0;
-}
-
-static __inline__ void jffs_fm_write_lock(struct jffs_fmcontrol *fmc)
-{
- // down(&fmc->wlock);
-}
-
-static __inline__ void jffs_fm_write_unlock(struct jffs_fmcontrol *fmc)
-{
- // up(&fmc->wlock);
-}
-
-
-/* Create and initialize a new struct jffs_file. */
-static struct jffs_file *
-jffs_create_file(struct jffs_control *c,
- const struct jffs_raw_inode *raw_inode)
-{
- struct jffs_file *f;
-
- if (!(f = kzalloc(sizeof(*f), GFP_KERNEL))) {
- D(printk("jffs_create_file(): Failed!\n"));
- return NULL;
- }
- no_jffs_file++;
- f->ino = raw_inode->ino;
- f->pino = raw_inode->pino;
- f->nlink = raw_inode->nlink;
- f->deleted = raw_inode->deleted;
- f->c = c;
-
- return f;
-}
-
-
-/* Build a control block for the file system. */
-static struct jffs_control *
-jffs_create_control(struct super_block *sb)
-{
- struct jffs_control *c;
- register int s = sizeof(struct jffs_control);
- int i;
- D(char *t = 0);
-
- D2(printk("jffs_create_control()\n"));
-
- if (!(c = kmalloc(s, GFP_KERNEL))) {
- goto fail_control;
- }
- DJM(no_jffs_control++);
- c->root = NULL;
- c->gc_task = NULL;
- c->hash_len = JFFS_HASH_SIZE;
- s = sizeof(struct list_head) * c->hash_len;
- if (!(c->hash = kmalloc(s, GFP_KERNEL))) {
- goto fail_hash;
- }
- DJM(no_hash++);
- for (i = 0; i < c->hash_len; i++)
- INIT_LIST_HEAD(&c->hash[i]);
- if (!(c->fmc = jffs_build_begin(c, MINOR(sb->s_dev)))) {
- goto fail_fminit;
- }
- c->next_ino = JFFS_MIN_INO + 1;
- c->delete_list = (struct jffs_delete_list *) 0;
- return c;
-
-fail_fminit:
- D(t = "c->fmc");
-fail_hash:
- kfree(c);
- DJM(no_jffs_control--);
- D(t = t ? t : "c->hash");
-fail_control:
- D(t = t ? t : "control");
- D(printk("jffs_create_control(): Allocation failed: (%s)\n", t));
- return (struct jffs_control *)0;
-}
-
-
-/* Clean up all data structures associated with the file system. */
-void
-jffs_cleanup_control(struct jffs_control *c)
-{
- D2(printk("jffs_cleanup_control()\n"));
-
- if (!c) {
- D(printk("jffs_cleanup_control(): c == NULL !!!\n"));
- return;
- }
-
- while (c->delete_list) {
- struct jffs_delete_list *delete_list_element;
- delete_list_element = c->delete_list;
- c->delete_list = c->delete_list->next;
- kfree(delete_list_element);
- }
-
- /* Free all files and nodes. */
- if (c->hash) {
- jffs_foreach_file(c, jffs_free_node_list);
- jffs_foreach_file(c, jffs_free_file);
- kfree(c->hash);
- DJM(no_hash--);
- }
- jffs_cleanup_fmcontrol(c->fmc);
- kfree(c);
- DJM(no_jffs_control--);
- D3(printk("jffs_cleanup_control(): Leaving...\n"));
-}
-
-
-/* This function adds a virtual root node to the in-RAM representation.
- Called by jffs_build_fs(). */
-static int
-jffs_add_virtual_root(struct jffs_control *c)
-{
- struct jffs_file *root;
- struct jffs_node *node;
-
- D2(printk("jffs_add_virtual_root(): "
- "Creating a virtual root directory.\n"));
-
- if (!(root = kzalloc(sizeof(struct jffs_file), GFP_KERNEL))) {
- return -ENOMEM;
- }
- no_jffs_file++;
- if (!(node = jffs_alloc_node())) {
- kfree(root);
- no_jffs_file--;
- return -ENOMEM;
- }
- DJM(no_jffs_node++);
- memset(node, 0, sizeof(struct jffs_node));
- node->ino = JFFS_MIN_INO;
- root->ino = JFFS_MIN_INO;
- root->mode = S_IFDIR | S_IRWXU | S_IRGRP
- | S_IXGRP | S_IROTH | S_IXOTH;
- root->atime = root->mtime = root->ctime = get_seconds();
- root->nlink = 1;
- root->c = c;
- root->version_head = root->version_tail = node;
- jffs_insert_file_into_hash(root);
- return 0;
-}
-
-
-/* This is where the file system is built and initialized. */
-int
-jffs_build_fs(struct super_block *sb)
-{
- struct jffs_control *c;
- int err = 0;
-
- D2(printk("jffs_build_fs()\n"));
-
- if (!(c = jffs_create_control(sb))) {
- return -ENOMEM;
- }
- c->building_fs = 1;
- c->sb = sb;
- if ((err = jffs_scan_flash(c)) < 0) {
- if(err == -EAGAIN){
- /* scan_flash() wants us to try once more. A flipping
- bits sector was detect in the middle of the scan flash.
- Clean up old allocated memory before going in.
- */
- D1(printk("jffs_build_fs: Cleaning up all control structures,"
- " reallocating them and trying mount again.\n"));
- jffs_cleanup_control(c);
- if (!(c = jffs_create_control(sb))) {
- return -ENOMEM;
- }
- c->building_fs = 1;
- c->sb = sb;
-
- if ((err = jffs_scan_flash(c)) < 0) {
- goto jffs_build_fs_fail;
- }
- }else{
- goto jffs_build_fs_fail;
- }
- }
-
- /* Add a virtual root node if no one exists. */
- if (!jffs_find_file(c, JFFS_MIN_INO)) {
- if ((err = jffs_add_virtual_root(c)) < 0) {
- goto jffs_build_fs_fail;
- }
- }
-
- while (c->delete_list) {
- struct jffs_file *f;
- struct jffs_delete_list *delete_list_element;
-
- if ((f = jffs_find_file(c, c->delete_list->ino))) {
- f->deleted = 1;
- }
- delete_list_element = c->delete_list;
- c->delete_list = c->delete_list->next;
- kfree(delete_list_element);
- }
-
- /* Remove deleted nodes. */
- if ((err = jffs_foreach_file(c, jffs_possibly_delete_file)) < 0) {
- printk(KERN_ERR "JFFS: Failed to remove deleted nodes.\n");
- goto jffs_build_fs_fail;
- }
- /* Remove redundant nodes. (We are not interested in the
- return value in this case.) */
- jffs_foreach_file(c, jffs_remove_redundant_nodes);
- /* Try to build a tree from all the nodes. */
- if ((err = jffs_foreach_file(c, jffs_insert_file_into_tree)) < 0) {
- printk("JFFS: Failed to build tree.\n");
- goto jffs_build_fs_fail;
- }
- /* Compute the sizes of all files in the filesystem. Adjust if
- necessary. */
- if ((err = jffs_foreach_file(c, jffs_build_file)) < 0) {
- printk("JFFS: Failed to build file system.\n");
- goto jffs_build_fs_fail;
- }
- sb->s_fs_info = (void *)c;
- c->building_fs = 0;
-
- D1(jffs_print_hash_table(c));
- D1(jffs_print_tree(c->root, 0));
-
- return 0;
-
-jffs_build_fs_fail:
- jffs_cleanup_control(c);
- return err;
-} /* jffs_build_fs() */
-
-
-/*
- This checks for sectors that were being erased in their previous
- lifetimes and for some reason or the other (power fail etc.),
- the erase cycles never completed.
- As the flash array would have reverted back to read status,
- these sectors are detected by the symptom of the "flipping bits",
- i.e. bits being read back differently from the same location in
- flash if read multiple times.
- The only solution to this is to re-erase the entire
- sector.
- Unfortunately detecting "flipping bits" is not a simple exercise
- as a bit may be read back at 1 or 0 depending on the alignment
- of the stars in the universe.
- The level of confidence is in direct proportion to the number of
- scans done. By power fail testing I (Vipin) have been able to
- proove that reading twice is not enough.
- Maybe 4 times? Change NUM_REREADS to a higher number if you want
- a (even) higher degree of confidence in your mount process.
- A higher number would of course slow down your mount.
-*/
-static int check_partly_erased_sectors(struct jffs_fmcontrol *fmc){
-
-#define NUM_REREADS 4 /* see note above */
-#define READ_AHEAD_BYTES 4096 /* must be a multiple of 4,
- usually set to kernel page size */
-
- __u8 *read_buf1;
- __u8 *read_buf2;
-
- int err = 0;
- int retlen;
- int i;
- int cnt;
- __u32 offset;
- loff_t pos = 0;
- loff_t end = fmc->flash_size;
-
-
- /* Allocate read buffers */
- read_buf1 = kmalloc(sizeof(__u8) * READ_AHEAD_BYTES, GFP_KERNEL);
- if (!read_buf1)
- return -ENOMEM;
-
- read_buf2 = kmalloc(sizeof(__u8) * READ_AHEAD_BYTES, GFP_KERNEL);
- if (!read_buf2) {
- kfree(read_buf1);
- return -ENOMEM;
- }
-
- CHECK_NEXT:
- while(pos < end){
-
- D1(printk("check_partly_erased_sector():checking sector which contains"
- " offset 0x%x for flipping bits..\n", (__u32)pos));
-
- retlen = flash_safe_read(fmc->mtd, pos,
- &read_buf1[0], READ_AHEAD_BYTES);
- retlen &= ~3;
-
- for(cnt = 0; cnt < NUM_REREADS; cnt++){
- (void)flash_safe_read(fmc->mtd, pos,
- &read_buf2[0], READ_AHEAD_BYTES);
-
- for (i=0 ; i < retlen ; i+=4) {
- /* buffers MUST match, double word for word! */
- if(*((__u32 *) &read_buf1[i]) !=
- *((__u32 *) &read_buf2[i])
- ){
- /* flipping bits detected, time to erase sector */
- /* This will help us log some statistics etc. */
- D1(printk("Flipping bits detected in re-read round:%i of %i\n",
- cnt, NUM_REREADS));
- D1(printk("check_partly_erased_sectors:flipping bits detected"
- " @offset:0x%x(0x%x!=0x%x)\n",
- (__u32)pos+i, *((__u32 *) &read_buf1[i]),
- *((__u32 *) &read_buf2[i])));
-
- /* calculate start of present sector */
- offset = (((__u32)pos+i)/(__u32)fmc->sector_size) * (__u32)fmc->sector_size;
-
- D1(printk("check_partly_erased_sector():erasing sector starting 0x%x.\n",
- offset));
-
- if (flash_erase_region(fmc->mtd,
- offset, fmc->sector_size) < 0) {
- printk(KERN_ERR "JFFS: Erase of flash failed. "
- "offset = %u, erase_size = %d\n",
- offset , fmc->sector_size);
-
- err = -EIO;
- goto returnBack;
-
- }else{
- D1(printk("JFFS: Erase of flash sector @0x%x successful.\n",
- offset));
- /* skip ahead to the next sector */
- pos = (((__u32)pos+i)/(__u32)fmc->sector_size) * (__u32)fmc->sector_size;
- pos += fmc->sector_size;
- goto CHECK_NEXT;
- }
- }
- }
- }
- pos += READ_AHEAD_BYTES;
- }
-
- returnBack:
- kfree(read_buf1);
- kfree(read_buf2);
-
- D2(printk("check_partly_erased_sector():Done checking all sectors till offset 0x%x for flipping bits.\n",
- (__u32)pos));
-
- return err;
-
-}/* end check_partly_erased_sectors() */
-
-
-
-/* Scan the whole flash memory in order to find all nodes in the
- file systems. */
-static int
-jffs_scan_flash(struct jffs_control *c)
-{
- char name[JFFS_MAX_NAME_LEN + 2];
- struct jffs_raw_inode raw_inode;
- struct jffs_node *node = NULL;
- struct jffs_fmcontrol *fmc = c->fmc;
- __u32 checksum;
- __u8 tmp_accurate;
- __u16 tmp_chksum;
- __u32 deleted_file;
- loff_t pos = 0;
- loff_t start;
- loff_t test_start;
- loff_t end = fmc->flash_size;
- __u8 *read_buf;
- int i, len, retlen;
- __u32 offset;
-
- __u32 free_chunk_size1;
- __u32 free_chunk_size2;
-
-
-#define NUMFREEALLOWED 2 /* 2 chunks of at least erase size space allowed */
- int num_free_space = 0; /* Flag err if more than TWO
- free blocks found. This is NOT allowed
- by the current jffs design.
- */
- int num_free_spc_not_accp = 0; /* For debugging purposed keep count
- of how much free space was rejected and
- marked dirty
- */
-
- D1(printk("jffs_scan_flash(): start pos = 0x%lx, end = 0x%lx\n",
- (long)pos, (long)end));
-
- flash_safe_acquire(fmc->mtd);
-
- /*
- check and make sure that any sector does not suffer
- from the "partly erased, bit flipping syndrome" (TM Vipin :)
- If so, offending sectors will be erased.
- */
- if(check_partly_erased_sectors(fmc) < 0){
-
- flash_safe_release(fmc->mtd);
- return -EIO; /* bad, bad, bad error. Cannot continue.*/
- }
-
- /* Allocate read buffer */
- read_buf = kmalloc(sizeof(__u8) * 4096, GFP_KERNEL);
- if (!read_buf) {
- flash_safe_release(fmc->mtd);
- return -ENOMEM;
- }
-
- /* Start the scan. */
- while (pos < end) {
- deleted_file = 0;
-
- /* Remember the position from where we started this scan. */
- start = pos;
-
- switch (flash_read_u32(fmc->mtd, pos)) {
- case JFFS_EMPTY_BITMASK:
- /* We have found 0xffffffff at this position. We have to
- scan the rest of the flash till the end or till
- something else than 0xffffffff is found.
- Keep going till we do not find JFFS_EMPTY_BITMASK
- anymore */
-
- D1(printk("jffs_scan_flash(): 0xffffffff at pos 0x%lx.\n",
- (long)pos));
-
- while(pos < end){
-
- len = end - pos < 4096 ? end - pos : 4096;
-
- retlen = flash_safe_read(fmc->mtd, pos,
- &read_buf[0], len);
-
- retlen &= ~3;
-
- for (i=0 ; i < retlen ; i+=4, pos += 4) {
- if(*((__u32 *) &read_buf[i]) !=
- JFFS_EMPTY_BITMASK)
- break;
- }
- if (i == retlen)
- continue;
- else
- break;
- }
-
- D1(printk("jffs_scan_flash():0xffffffff ended at pos 0x%lx.\n",
- (long)pos));
-
- /* If some free space ends in the middle of a sector,
- treat it as dirty rather than clean.
- This is to handle the case where one thread
- allocated space for a node, but didn't get to
- actually _write_ it before power was lost, leaving
- a gap in the log. Shifting all node writes into
- a single kernel thread will fix the original problem.
- */
- if ((__u32) pos % fmc->sector_size) {
- /* If there was free space in previous
- sectors, don't mark that dirty too -
- only from the beginning of this sector
- (or from start)
- */
-
- test_start = pos & ~(fmc->sector_size-1); /* end of last sector */
-
- if (start < test_start) {
-
- /* free space started in the previous sector! */
-
- if((num_free_space < NUMFREEALLOWED) &&
- ((unsigned int)(test_start - start) >= fmc->sector_size)){
-
- /*
- Count it in if we are still under NUMFREEALLOWED *and* it is
- at least 1 erase sector in length. This will keep us from
- picking any little ole' space as "free".
- */
-
- D1(printk("Reducing end of free space to 0x%x from 0x%x\n",
- (unsigned int)test_start, (unsigned int)pos));
-
- D1(printk("Free space accepted: Starting 0x%x for 0x%x bytes\n",
- (unsigned int) start,
- (unsigned int)(test_start - start)));
-
- /* below, space from "start" to "pos" will be marked dirty. */
- start = test_start;
-
- /* Being in here means that we have found at least an entire
- erase sector size of free space ending on a sector boundary.
- Keep track of free spaces accepted.
- */
- num_free_space++;
- }else{
- num_free_spc_not_accp++;
- D1(printk("Free space (#%i) found but *Not* accepted: Starting"
- " 0x%x for 0x%x bytes\n",
- num_free_spc_not_accp, (unsigned int)start,
- (unsigned int)((unsigned int)(pos & ~(fmc->sector_size-1)) - (unsigned int)start)));
-
- }
-
- }
- if((((__u32)(pos - start)) != 0)){
-
- D1(printk("Dirty space: Starting 0x%x for 0x%x bytes\n",
- (unsigned int) start, (unsigned int) (pos - start)));
- jffs_fmalloced(fmc, (__u32) start,
- (__u32) (pos - start), NULL);
- }else{
- /* "Flipping bits" detected. This means that our scan for them
- did not catch this offset. See check_partly_erased_sectors() for
- more info.
- */
-
- D1(printk("jffs_scan_flash():wants to allocate dirty flash "
- "space for 0 bytes.\n"));
- D1(printk("jffs_scan_flash(): Flipping bits! We will free "
- "all allocated memory, erase this sector and remount\n"));
-
- /* calculate start of present sector */
- offset = (((__u32)pos)/(__u32)fmc->sector_size) * (__u32)fmc->sector_size;
-
- D1(printk("jffs_scan_flash():erasing sector starting 0x%x.\n",
- offset));
-
- if (flash_erase_region(fmc->mtd,
- offset, fmc->sector_size) < 0) {
- printk(KERN_ERR "JFFS: Erase of flash failed. "
- "offset = %u, erase_size = %d\n",
- offset , fmc->sector_size);
-
- flash_safe_release(fmc->mtd);
- kfree(read_buf);
- return -1; /* bad, bad, bad! */
-
- }
- flash_safe_release(fmc->mtd);
- kfree(read_buf);
-
- return -EAGAIN; /* erased offending sector. Try mount one more time please. */
- }
- }else{
- /* Being in here means that we have found free space that ends on an erase sector
- boundary.
- Count it in if we are still under NUMFREEALLOWED *and* it is at least 1 erase
- sector in length. This will keep us from picking any little ole' space as "free".
- */
- if((num_free_space < NUMFREEALLOWED) &&
- ((unsigned int)(pos - start) >= fmc->sector_size)){
- /* We really don't do anything to mark space as free, except *not*
- mark it dirty and just advance the "pos" location pointer.
- It will automatically be picked up as free space.
- */
- num_free_space++;
- D1(printk("Free space accepted: Starting 0x%x for 0x%x bytes\n",
- (unsigned int) start, (unsigned int) (pos - start)));
- }else{
- num_free_spc_not_accp++;
- D1(printk("Free space (#%i) found but *Not* accepted: Starting "
- "0x%x for 0x%x bytes\n", num_free_spc_not_accp,
- (unsigned int) start,
- (unsigned int) (pos - start)));
-
- /* Mark this space as dirty. We already have our free space. */
- D1(printk("Dirty space: Starting 0x%x for 0x%x bytes\n",
- (unsigned int) start, (unsigned int) (pos - start)));
- jffs_fmalloced(fmc, (__u32) start,
- (__u32) (pos - start), NULL);
- }
-
- }
- if(num_free_space > NUMFREEALLOWED){
- printk(KERN_WARNING "jffs_scan_flash(): Found free space "
- "number %i. Only %i free space is allowed.\n",
- num_free_space, NUMFREEALLOWED);
- }
- continue;
-
- case JFFS_DIRTY_BITMASK:
- /* We have found 0x00000000 at this position. Scan as far
- as possible to find out how much is dirty. */
- D1(printk("jffs_scan_flash(): 0x00000000 at pos 0x%lx.\n",
- (long)pos));
- for (; pos < end
- && JFFS_DIRTY_BITMASK == flash_read_u32(fmc->mtd, pos);
- pos += 4);
- D1(printk("jffs_scan_flash(): 0x00 ended at "
- "pos 0x%lx.\n", (long)pos));
- jffs_fmalloced(fmc, (__u32) start,
- (__u32) (pos - start), NULL);
- continue;
-
- case JFFS_MAGIC_BITMASK:
- /* We have probably found a new raw inode. */
- break;
-
- default:
- bad_inode:
- /* We're f*cked. This is not solved yet. We have
- to scan for the magic pattern. */
- D1(printk("*************** Dirty flash memory or "
- "bad inode: "
- "hexdump(pos = 0x%lx, len = 128):\n",
- (long)pos));
- D1(jffs_hexdump(fmc->mtd, pos, 128));
-
- for (pos += 4; pos < end; pos += 4) {
- switch (flash_read_u32(fmc->mtd, pos)) {
- case JFFS_MAGIC_BITMASK:
- case JFFS_EMPTY_BITMASK:
- /* handle these in the main switch() loop */
- goto cont_scan;
-
- default:
- break;
- }
- }
-
- cont_scan:
- /* First, mark as dirty the region
- which really does contain crap. */
- jffs_fmalloced(fmc, (__u32) start,
- (__u32) (pos - start),
- NULL);
-
- continue;
- }/* switch */
-
- /* We have found the beginning of an inode. Create a
- node for it unless there already is one available. */
- if (!node) {
- if (!(node = jffs_alloc_node())) {
- /* Free read buffer */
- kfree(read_buf);
-
- /* Release the flash device */
- flash_safe_release(fmc->mtd);
-
- return -ENOMEM;
- }
- DJM(no_jffs_node++);
- }
-
- /* Read the next raw inode. */
-
- flash_safe_read(fmc->mtd, pos, (u_char *) &raw_inode,
- sizeof(struct jffs_raw_inode));
-
- /* When we compute the checksum for the inode, we never
- count the 'accurate' or the 'checksum' fields. */
- tmp_accurate = raw_inode.accurate;
- tmp_chksum = raw_inode.chksum;
- raw_inode.accurate = 0;
- raw_inode.chksum = 0;
- checksum = jffs_checksum(&raw_inode,
- sizeof(struct jffs_raw_inode));
- raw_inode.accurate = tmp_accurate;
- raw_inode.chksum = tmp_chksum;
-
- D3(printk("*** We have found this raw inode at pos 0x%lx "
- "on the flash:\n", (long)pos));
- D3(jffs_print_raw_inode(&raw_inode));
-
- if (checksum != raw_inode.chksum) {
- D1(printk("jffs_scan_flash(): Bad checksum: "
- "checksum = %u, "
- "raw_inode.chksum = %u\n",
- checksum, raw_inode.chksum));
- pos += sizeof(struct jffs_raw_inode);
- jffs_fmalloced(fmc, (__u32) start,
- (__u32) (pos - start), NULL);
- /* Reuse this unused struct jffs_node. */
- continue;
- }
-
- /* Check the raw inode read so far. Start with the
- maximum length of the filename. */
- if (raw_inode.nsize > JFFS_MAX_NAME_LEN) {
- printk(KERN_WARNING "jffs_scan_flash: Found a "
- "JFFS node with name too large\n");
- goto bad_inode;
- }
-
- if (raw_inode.rename && raw_inode.dsize != sizeof(__u32)) {
- printk(KERN_WARNING "jffs_scan_flash: Found a "
- "rename node with dsize %u.\n",
- raw_inode.dsize);
- jffs_print_raw_inode(&raw_inode);
- goto bad_inode;
- }
-
- /* The node's data segment should not exceed a
- certain length. */
- if (raw_inode.dsize > fmc->max_chunk_size) {
- printk(KERN_WARNING "jffs_scan_flash: Found a "
- "JFFS node with dsize (0x%x) > max_chunk_size (0x%x)\n",
- raw_inode.dsize, fmc->max_chunk_size);
- goto bad_inode;
- }
-
- pos += sizeof(struct jffs_raw_inode);
-
- /* This shouldn't be necessary because a node that
- violates the flash boundaries shouldn't be written
- in the first place. */
- if (pos >= end) {
- goto check_node;
- }
-
- /* Read the name. */
- *name = 0;
- if (raw_inode.nsize) {
- flash_safe_read(fmc->mtd, pos, name, raw_inode.nsize);
- name[raw_inode.nsize] = '\0';
- pos += raw_inode.nsize
- + JFFS_GET_PAD_BYTES(raw_inode.nsize);
- D3(printk("name == \"%s\"\n", name));
- checksum = jffs_checksum(name, raw_inode.nsize);
- if (checksum != raw_inode.nchksum) {
- D1(printk("jffs_scan_flash(): Bad checksum: "
- "checksum = %u, "
- "raw_inode.nchksum = %u\n",
- checksum, raw_inode.nchksum));
- jffs_fmalloced(fmc, (__u32) start,
- (__u32) (pos - start), NULL);
- /* Reuse this unused struct jffs_node. */
- continue;
- }
- if (pos >= end) {
- goto check_node;
- }
- }
-
- /* Read the data, if it exists, in order to be sure it
- matches the checksum. */
- if (raw_inode.dsize) {
- if (raw_inode.rename) {
- deleted_file = flash_read_u32(fmc->mtd, pos);
- }
- if (jffs_checksum_flash(fmc->mtd, pos, raw_inode.dsize, &checksum)) {
- printk("jffs_checksum_flash() failed to calculate a checksum\n");
- jffs_fmalloced(fmc, (__u32) start,
- (__u32) (pos - start), NULL);
- /* Reuse this unused struct jffs_node. */
- continue;
- }
- pos += raw_inode.dsize
- + JFFS_GET_PAD_BYTES(raw_inode.dsize);
-
- if (checksum != raw_inode.dchksum) {
- D1(printk("jffs_scan_flash(): Bad checksum: "
- "checksum = %u, "
- "raw_inode.dchksum = %u\n",
- checksum, raw_inode.dchksum));
- jffs_fmalloced(fmc, (__u32) start,
- (__u32) (pos - start), NULL);
- /* Reuse this unused struct jffs_node. */
- continue;
- }
- }
-
- check_node:
-
- /* Remember the highest inode number in the whole file
- system. This information will be used when assigning
- new files new inode numbers. */
- if (c->next_ino <= raw_inode.ino) {
- c->next_ino = raw_inode.ino + 1;
- }
-
- if (raw_inode.accurate) {
- int err;
- node->data_offset = raw_inode.offset;
- node->data_size = raw_inode.dsize;
- node->removed_size = raw_inode.rsize;
- /* Compute the offset to the actual data in the
- on-flash node. */
- node->fm_offset
- = sizeof(struct jffs_raw_inode)
- + raw_inode.nsize
- + JFFS_GET_PAD_BYTES(raw_inode.nsize);
- node->fm = jffs_fmalloced(fmc, (__u32) start,
- (__u32) (pos - start),
- node);
- if (!node->fm) {
- D(printk("jffs_scan_flash(): !node->fm\n"));
- jffs_free_node(node);
- DJM(no_jffs_node--);
-
- /* Free read buffer */
- kfree(read_buf);
-
- /* Release the flash device */
- flash_safe_release(fmc->mtd);
-
- return -ENOMEM;
- }
- if ((err = jffs_insert_node(c, NULL, &raw_inode,
- name, node)) < 0) {
- printk("JFFS: Failed to handle raw inode. "
- "(err = %d)\n", err);
- break;
- }
- if (raw_inode.rename) {
- struct jffs_delete_list *dl
- = (struct jffs_delete_list *)
- kmalloc(sizeof(struct jffs_delete_list),
- GFP_KERNEL);
- if (!dl) {
- D(printk("jffs_scan_flash: !dl\n"));
- jffs_free_node(node);
- DJM(no_jffs_node--);
-
- /* Release the flash device */
- flash_safe_release(fmc->flash_part);
-
- /* Free read buffer */
- kfree(read_buf);
-
- return -ENOMEM;
- }
- dl->ino = deleted_file;
- dl->next = c->delete_list;
- c->delete_list = dl;
- node->data_size = 0;
- }
- D3(jffs_print_node(node));
- node = NULL; /* Don't free the node! */
- }
- else {
- jffs_fmalloced(fmc, (__u32) start,
- (__u32) (pos - start), NULL);
- D3(printk("jffs_scan_flash(): Just found an obsolete "
- "raw_inode. Continuing the scan...\n"));
- /* Reuse this unused struct jffs_node. */
- }
- }
-
- if (node) {
- jffs_free_node(node);
- DJM(no_jffs_node--);
- }
- jffs_build_end(fmc);
-
- /* Free read buffer */
- kfree(read_buf);
-
- if(!num_free_space){
- printk(KERN_WARNING "jffs_scan_flash(): Did not find even a single "
- "chunk of free space. This is BAD!\n");
- }
-
- /* Return happy */
- D3(printk("jffs_scan_flash(): Leaving...\n"));
- flash_safe_release(fmc->mtd);
-
- /* This is to trap the "free size accounting screwed error. */
- free_chunk_size1 = jffs_free_size1(fmc);
- free_chunk_size2 = jffs_free_size2(fmc);
-
- if (free_chunk_size1 + free_chunk_size2 != fmc->free_size) {
-
- printk(KERN_WARNING "jffs_scan_falsh():Free size accounting screwed\n");
- printk(KERN_WARNING "jfffs_scan_flash():free_chunk_size1 == 0x%x, "
- "free_chunk_size2 == 0x%x, fmc->free_size == 0x%x\n",
- free_chunk_size1, free_chunk_size2, fmc->free_size);
-
- return -1; /* Do NOT mount f/s so that we can inspect what happened.
- Mounting this screwed up f/s will screw us up anyway.
- */
- }
-
- return 0; /* as far as we are concerned, we are happy! */
-} /* jffs_scan_flash() */
-
-
-/* Insert any kind of node into the file system. Take care of data
- insertions and deletions. Also remove redundant information. The
- memory allocated for the `name' is regarded as "given away" in the
- caller's perspective. */
-int
-jffs_insert_node(struct jffs_control *c, struct jffs_file *f,
- const struct jffs_raw_inode *raw_inode,
- const char *name, struct jffs_node *node)
-{
- int update_name = 0;
- int insert_into_tree = 0;
-
- D2(printk("jffs_insert_node(): ino = %u, version = %u, "
- "name = \"%s\", deleted = %d\n",
- raw_inode->ino, raw_inode->version,
- ((name && *name) ? name : ""), raw_inode->deleted));
-
- /* If there doesn't exist an associated jffs_file, then
- create, initialize and insert one into the file system. */
- if (!f && !(f = jffs_find_file(c, raw_inode->ino))) {
- if (!(f = jffs_create_file(c, raw_inode))) {
- return -ENOMEM;
- }
- jffs_insert_file_into_hash(f);
- insert_into_tree = 1;
- }
- node->ino = raw_inode->ino;
- node->version = raw_inode->version;
- node->data_size = raw_inode->dsize;
- node->fm_offset = sizeof(struct jffs_raw_inode) + raw_inode->nsize
- + JFFS_GET_PAD_BYTES(raw_inode->nsize);
- node->name_size = raw_inode->nsize;
-
- /* Now insert the node at the correct position into the file's
- version list. */
- if (!f->version_head) {
- /* This is the first node. */
- f->version_head = node;
- f->version_tail = node;
- node->version_prev = NULL;
- node->version_next = NULL;
- f->highest_version = node->version;
- update_name = 1;
- f->mode = raw_inode->mode;
- f->uid = raw_inode->uid;
- f->gid = raw_inode->gid;
- f->atime = raw_inode->atime;
- f->mtime = raw_inode->mtime;
- f->ctime = raw_inode->ctime;
- }
- else if ((f->highest_version < node->version)
- || (node->version == 0)) {
- /* Insert at the end of the list. I.e. this node is the
- newest one so far. */
- node->version_prev = f->version_tail;
- node->version_next = NULL;
- f->version_tail->version_next = node;
- f->version_tail = node;
- f->highest_version = node->version;
- update_name = 1;
- f->pino = raw_inode->pino;
- f->mode = raw_inode->mode;
- f->uid = raw_inode->uid;
- f->gid = raw_inode->gid;
- f->atime = raw_inode->atime;
- f->mtime = raw_inode->mtime;
- f->ctime = raw_inode->ctime;
- }
- else if (f->version_head->version > node->version) {
- /* Insert at the bottom of the list. */
- node->version_prev = NULL;
- node->version_next = f->version_head;
- f->version_head->version_prev = node;
- f->version_head = node;
- if (!f->name) {
- update_name = 1;
- }
- }
- else {
- struct jffs_node *n;
- int newer_name = 0;
- /* Search for the insertion position starting from
- the tail (newest node). */
- for (n = f->version_tail; n; n = n->version_prev) {
- if (n->version < node->version) {
- node->version_prev = n;
- node->version_next = n->version_next;
- node->version_next->version_prev = node;
- n->version_next = node;
- if (!newer_name) {
- update_name = 1;
- }
- break;
- }
- if (n->name_size) {
- newer_name = 1;
- }
- }
- }
-
- /* Deletion is irreversible. If any 'deleted' node is ever
- written, the file is deleted */
- if (raw_inode->deleted)
- f->deleted = raw_inode->deleted;
-
- /* Perhaps update the name. */
- if (raw_inode->nsize && update_name && name && *name && (name != f->name)) {
- if (f->name) {
- kfree(f->name);
- DJM(no_name--);
- }
- if (!(f->name = kmalloc(raw_inode->nsize + 1,
- GFP_KERNEL))) {
- return -ENOMEM;
- }
- DJM(no_name++);
- memcpy(f->name, name, raw_inode->nsize);
- f->name[raw_inode->nsize] = '\0';
- f->nsize = raw_inode->nsize;
- D3(printk("jffs_insert_node(): Updated the name of "
- "the file to \"%s\".\n", name));
- }
-
- if (!c->building_fs) {
- D3(printk("jffs_insert_node(): ---------------------------"
- "------------------------------------------- 1\n"));
- if (insert_into_tree) {
- jffs_insert_file_into_tree(f);
- }
- /* Once upon a time, we would call jffs_possibly_delete_file()
- here. That causes an oops if someone's still got the file
- open, so now we only do it in jffs_delete_inode()
- -- dwmw2
- */
- if (node->data_size || node->removed_size) {
- jffs_update_file(f, node);
- }
- jffs_remove_redundant_nodes(f);
-
- jffs_garbage_collect_trigger(c);
-
- D3(printk("jffs_insert_node(): ---------------------------"
- "------------------------------------------- 2\n"));
- }
-
- return 0;
-} /* jffs_insert_node() */
-
-
-/* Unlink a jffs_node from the version list it is in. */
-static inline void
-jffs_unlink_node_from_version_list(struct jffs_file *f,
- struct jffs_node *node)
-{
- if (node->version_prev) {
- node->version_prev->version_next = node->version_next;
- } else {
- f->version_head = node->version_next;
- }
- if (node->version_next) {
- node->version_next->version_prev = node->version_prev;
- } else {
- f->version_tail = node->version_prev;
- }
-}
-
-
-/* Unlink a jffs_node from the range list it is in. */
-static inline void
-jffs_unlink_node_from_range_list(struct jffs_file *f, struct jffs_node *node)
-{
- if (node->range_prev) {
- node->range_prev->range_next = node->range_next;
- }
- else {
- f->range_head = node->range_next;
- }
- if (node->range_next) {
- node->range_next->range_prev = node->range_prev;
- }
- else {
- f->range_tail = node->range_prev;
- }
-}
-
-
-/* Function used by jffs_remove_redundant_nodes() below. This function
- classifies what kind of information a node adds to a file. */
-static inline __u8
-jffs_classify_node(struct jffs_node *node)
-{
- __u8 mod_type = JFFS_MODIFY_INODE;
-
- if (node->name_size) {
- mod_type |= JFFS_MODIFY_NAME;
- }
- if (node->data_size || node->removed_size) {
- mod_type |= JFFS_MODIFY_DATA;
- }
- return mod_type;
-}
-
-
-/* Remove redundant nodes from a file. Mark the on-flash memory
- as dirty. */
-static int
-jffs_remove_redundant_nodes(struct jffs_file *f)
-{
- struct jffs_node *newest_node;
- struct jffs_node *cur;
- struct jffs_node *prev;
- __u8 newest_type;
- __u8 mod_type;
- __u8 node_with_name_later = 0;
-
- if (!(newest_node = f->version_tail)) {
- return 0;
- }
-
- /* What does the `newest_node' modify? */
- newest_type = jffs_classify_node(newest_node);
- node_with_name_later = newest_type & JFFS_MODIFY_NAME;
-
- D3(printk("jffs_remove_redundant_nodes(): ino: %u, name: \"%s\", "
- "newest_type: %u\n", f->ino, (f->name ? f->name : ""),
- newest_type));
-
- /* Traverse the file's nodes and determine which of them that are
- superfluous. Yeah, this might look very complex at first
- glance but it is actually very simple. */
- for (cur = newest_node->version_prev; cur; cur = prev) {
- prev = cur->version_prev;
- mod_type = jffs_classify_node(cur);
- if ((mod_type <= JFFS_MODIFY_INODE)
- || ((newest_type & JFFS_MODIFY_NAME)
- && (mod_type
- <= (JFFS_MODIFY_INODE + JFFS_MODIFY_NAME)))
- || (cur->data_size == 0 && cur->removed_size
- && !cur->version_prev && node_with_name_later)) {
- /* Yes, this node is redundant. Remove it. */
- D2(printk("jffs_remove_redundant_nodes(): "
- "Removing node: ino: %u, version: %u, "
- "mod_type: %u\n", cur->ino, cur->version,
- mod_type));
- jffs_unlink_node_from_version_list(f, cur);
- jffs_fmfree(f->c->fmc, cur->fm, cur);
- jffs_free_node(cur);
- DJM(no_jffs_node--);
- }
- else {
- node_with_name_later |= (mod_type & JFFS_MODIFY_NAME);
- }
- }
-
- return 0;
-}
-
-
-/* Insert a file into the hash table. */
-static int
-jffs_insert_file_into_hash(struct jffs_file *f)
-{
- int i = f->ino % f->c->hash_len;
-
- D3(printk("jffs_insert_file_into_hash(): f->ino: %u\n", f->ino));
-
- list_add(&f->hash, &f->c->hash[i]);
- return 0;
-}
-
-
-/* Insert a file into the file system tree. */
-int
-jffs_insert_file_into_tree(struct jffs_file *f)
-{
- struct jffs_file *parent;
-
- D3(printk("jffs_insert_file_into_tree(): name: \"%s\"\n",
- (f->name ? f->name : "")));
-
- if (!(parent = jffs_find_file(f->c, f->pino))) {
- if (f->pino == 0) {
- f->c->root = f;
- f->parent = NULL;
- f->sibling_prev = NULL;
- f->sibling_next = NULL;
- return 0;
- }
- else {
- D1(printk("jffs_insert_file_into_tree(): Found "
- "inode with no parent and pino == %u\n",
- f->pino));
- return -1;
- }
- }
- f->parent = parent;
- f->sibling_next = parent->children;
- if (f->sibling_next) {
- f->sibling_next->sibling_prev = f;
- }
- f->sibling_prev = NULL;
- parent->children = f;
- return 0;
-}
-
-
-/* Remove a file from the hash table. */
-static int
-jffs_unlink_file_from_hash(struct jffs_file *f)
-{
- D3(printk("jffs_unlink_file_from_hash(): f: 0x%p, "
- "ino %u\n", f, f->ino));
-
- list_del(&f->hash);
- return 0;
-}
-
-
-/* Just remove the file from the parent's children. Don't free
- any memory. */
-int
-jffs_unlink_file_from_tree(struct jffs_file *f)
-{
- D3(printk("jffs_unlink_file_from_tree(): ino: %d, pino: %d, name: "
- "\"%s\"\n", f->ino, f->pino, (f->name ? f->name : "")));
-
- if (f->sibling_prev) {
- f->sibling_prev->sibling_next = f->sibling_next;
- }
- else if (f->parent) {
- D3(printk("f->parent=%p\n", f->parent));
- f->parent->children = f->sibling_next;
- }
- if (f->sibling_next) {
- f->sibling_next->sibling_prev = f->sibling_prev;
- }
- return 0;
-}
-
-
-/* Find a file with its inode number. */
-struct jffs_file *
-jffs_find_file(struct jffs_control *c, __u32 ino)
-{
- struct jffs_file *f;
- int i = ino % c->hash_len;
-
- D3(printk("jffs_find_file(): ino: %u\n", ino));
-
- list_for_each_entry(f, &c->hash[i], hash) {
- if (ino != f->ino)
- continue;
- D3(printk("jffs_find_file(): Found file with ino "
- "%u. (name: \"%s\")\n",
- ino, (f->name ? f->name : ""));
- );
- return f;
- }
- D3(printk("jffs_find_file(): Didn't find file "
- "with ino %u.\n", ino);
- );
- return NULL;
-}
-
-
-/* Find a file in a directory. We are comparing the names. */
-struct jffs_file *
-jffs_find_child(struct jffs_file *dir, const char *name, int len)
-{
- struct jffs_file *f;
-
- D3(printk("jffs_find_child()\n"));
-
- for (f = dir->children; f; f = f->sibling_next) {
- if (!f->deleted && f->name
- && !strncmp(f->name, name, len)
- && f->name[len] == '\0') {
- break;
- }
- }
-
- D3(if (f) {
- printk("jffs_find_child(): Found \"%s\".\n", f->name);
- }
- else {
- char *copy = kmalloc(len + 1, GFP_KERNEL);
- if (copy) {
- memcpy(copy, name, len);
- copy[len] = '\0';
- }
- printk("jffs_find_child(): Didn't find the file \"%s\".\n",
- (copy ? copy : ""));
- kfree(copy);
- });
-
- return f;
-}
-
-
-/* Write a raw inode that takes up a certain amount of space in the flash
- memory. At the end of the flash device, there is often space that is
- impossible to use. At these times we want to mark this space as not
- used. In the cases when the amount of space is greater or equal than
- a struct jffs_raw_inode, we write a "dummy node" that takes up this
- space. The space after the raw inode, if it exists, is left as it is.
- Since this space after the raw inode contains JFFS_EMPTY_BITMASK bytes,
- we can compute the checksum of it; we don't have to manipulate it any
- further.
-
- If the space left on the device is less than the size of a struct
- jffs_raw_inode, this space is filled with JFFS_DIRTY_BITMASK bytes.
- No raw inode is written this time. */
-static int
-jffs_write_dummy_node(struct jffs_control *c, struct jffs_fm *dirty_fm)
-{
- struct jffs_fmcontrol *fmc = c->fmc;
- int err;
-
- D1(printk("jffs_write_dummy_node(): dirty_fm->offset = 0x%08x, "
- "dirty_fm->size = %u\n",
- dirty_fm->offset, dirty_fm->size));
-
- if (dirty_fm->size >= sizeof(struct jffs_raw_inode)) {
- struct jffs_raw_inode raw_inode;
- memset(&raw_inode, 0, sizeof(struct jffs_raw_inode));
- raw_inode.magic = JFFS_MAGIC_BITMASK;
- raw_inode.dsize = dirty_fm->size
- - sizeof(struct jffs_raw_inode);
- raw_inode.dchksum = raw_inode.dsize * 0xff;
- raw_inode.chksum
- = jffs_checksum(&raw_inode, sizeof(struct jffs_raw_inode));
-
- if ((err = flash_safe_write(fmc->mtd,
- dirty_fm->offset,
- (u_char *)&raw_inode,
- sizeof(struct jffs_raw_inode)))
- < 0) {
- printk(KERN_ERR "JFFS: jffs_write_dummy_node: "
- "flash_safe_write failed!\n");
- return err;
- }
- }
- else {
- flash_safe_acquire(fmc->mtd);
- flash_memset(fmc->mtd, dirty_fm->offset, 0, dirty_fm->size);
- flash_safe_release(fmc->mtd);
- }
-
- D3(printk("jffs_write_dummy_node(): Leaving...\n"));
- return 0;
-}
-
-
-/* Write a raw inode, possibly its name and possibly some data. */
-int
-jffs_write_node(struct jffs_control *c, struct jffs_node *node,
- struct jffs_raw_inode *raw_inode,
- const char *name, const unsigned char *data,
- int recoverable,
- struct jffs_file *f)
-{
- struct jffs_fmcontrol *fmc = c->fmc;
- struct jffs_fm *fm;
- struct kvec node_iovec[4];
- unsigned long iovec_cnt;
-
- __u32 pos;
- int err;
- __u32 slack = 0;
-
- __u32 total_name_size = raw_inode->nsize
- + JFFS_GET_PAD_BYTES(raw_inode->nsize);
- __u32 total_data_size = raw_inode->dsize
- + JFFS_GET_PAD_BYTES(raw_inode->dsize);
- __u32 total_size = sizeof(struct jffs_raw_inode)
- + total_name_size + total_data_size;
-
- /* If this node isn't something that will eventually let
- GC free even more space, then don't allow it unless
- there's at least max_chunk_size space still available
- */
- if (!recoverable)
- slack = fmc->max_chunk_size;
-
-
- /* Fire the retrorockets and shoot the fruiton torpedoes, sir! */
-
- ASSERT(if (!node) {
- printk("jffs_write_node(): node == NULL\n");
- return -EINVAL;
- });
- ASSERT(if (raw_inode && raw_inode->nsize && !name) {
- printk("*** jffs_write_node(): nsize = %u but name == NULL\n",
- raw_inode->nsize);
- return -EINVAL;
- });
-
- D1(printk("jffs_write_node(): filename = \"%s\", ino = %u, "
- "total_size = %u\n",
- (name ? name : ""), raw_inode->ino,
- total_size));
-
- jffs_fm_write_lock(fmc);
-
-retry:
- fm = NULL;
- err = 0;
- while (!fm) {
-
- /* Deadlocks suck. */
- while(fmc->free_size < fmc->min_free_size + total_size + slack) {
- jffs_fm_write_unlock(fmc);
- if (!JFFS_ENOUGH_SPACE(c, total_size + slack))
- return -ENOSPC;
- jffs_fm_write_lock(fmc);
- }
-
- /* First try to allocate some flash memory. */
- err = jffs_fmalloc(fmc, total_size, node, &fm);
-
- if (err == -ENOSPC) {
- /* Just out of space. GC and try again */
- if (fmc->dirty_size < fmc->sector_size) {
- D(printk("jffs_write_node(): jffs_fmalloc(0x%p, %u) "
- "failed, no dirty space to GC\n", fmc,
- total_size));
- return err;
- }
-
- D1(printk(KERN_INFO "jffs_write_node(): Calling jffs_garbage_collect_now()\n"));
- jffs_fm_write_unlock(fmc);
- if ((err = jffs_garbage_collect_now(c))) {
- D(printk("jffs_write_node(): jffs_garbage_collect_now() failed\n"));
- return err;
- }
- jffs_fm_write_lock(fmc);
- continue;
- }
-
- if (err < 0) {
- jffs_fm_write_unlock(fmc);
-
- D(printk("jffs_write_node(): jffs_fmalloc(0x%p, %u) "
- "failed!\n", fmc, total_size));
- return err;
- }
-
- if (!fm->nodes) {
- /* The jffs_fm struct that we got is not good enough.
- Make that space dirty and try again */
- if ((err = jffs_write_dummy_node(c, fm)) < 0) {
- kfree(fm);
- DJM(no_jffs_fm--);
- jffs_fm_write_unlock(fmc);
- D(printk("jffs_write_node(): "
- "jffs_write_dummy_node(): Failed!\n"));
- return err;
- }
- fm = NULL;
- }
- } /* while(!fm) */
- node->fm = fm;
-
- ASSERT(if (fm->nodes == 0) {
- printk(KERN_ERR "jffs_write_node(): fm->nodes == 0\n");
- });
-
- pos = node->fm->offset;
-
- /* Increment the version number here. We can't let the caller
- set it beforehand, because we might have had to do GC on a node
- of this file - and we'd end up reusing version numbers.
- */
- if (f) {
- raw_inode->version = f->highest_version + 1;
- D1(printk (KERN_NOTICE "jffs_write_node(): setting version of %s to %d\n", f->name, raw_inode->version));
-
- /* if the file was deleted, set the deleted bit in the raw inode */
- if (f->deleted)
- raw_inode->deleted = 1;
- }
-
- /* Compute the checksum for the data and name chunks. */
- raw_inode->dchksum = jffs_checksum(data, raw_inode->dsize);
- raw_inode->nchksum = jffs_checksum(name, raw_inode->nsize);
-
- /* The checksum is calculated without the chksum and accurate
- fields so set them to zero first. */
- raw_inode->accurate = 0;
- raw_inode->chksum = 0;
- raw_inode->chksum = jffs_checksum(raw_inode,
- sizeof(struct jffs_raw_inode));
- raw_inode->accurate = 0xff;
-
- D3(printk("jffs_write_node(): About to write this raw inode to the "
- "flash at pos 0x%lx:\n", (long)pos));
- D3(jffs_print_raw_inode(raw_inode));
-
- /* The actual raw JFFS node */
- node_iovec[0].iov_base = (void *) raw_inode;
- node_iovec[0].iov_len = (size_t) sizeof(struct jffs_raw_inode);
- iovec_cnt = 1;
-
- /* Get name and size if there is one */
- if (raw_inode->nsize) {
- node_iovec[iovec_cnt].iov_base = (void *) name;
- node_iovec[iovec_cnt].iov_len = (size_t) raw_inode->nsize;
- iovec_cnt++;
-
- if (JFFS_GET_PAD_BYTES(raw_inode->nsize)) {
- static unsigned char allff[3]={255,255,255};
- /* Add some extra padding if necessary */
- node_iovec[iovec_cnt].iov_base = allff;
- node_iovec[iovec_cnt].iov_len =
- JFFS_GET_PAD_BYTES(raw_inode->nsize);
- iovec_cnt++;
- }
- }
-
- /* Get data and size if there is any */
- if (raw_inode->dsize) {
- node_iovec[iovec_cnt].iov_base = (void *) data;
- node_iovec[iovec_cnt].iov_len = (size_t) raw_inode->dsize;
- iovec_cnt++;
- /* No need to pad this because we're not actually putting
- anything after it.
- */
- }
-
- if ((err = flash_safe_writev(fmc->mtd, node_iovec, iovec_cnt,
- pos)) < 0) {
- jffs_fmfree_partly(fmc, fm, 0);
- jffs_fm_write_unlock(fmc);
- printk(KERN_ERR "JFFS: jffs_write_node: Failed to write, "
- "requested %i, wrote %i\n", total_size, err);
- goto retry;
- }
- if (raw_inode->deleted)
- f->deleted = 1;
-
- jffs_fm_write_unlock(fmc);
- D3(printk("jffs_write_node(): Leaving...\n"));
- return raw_inode->dsize;
-} /* jffs_write_node() */
-
-
-/* Read data from the node and write it to the buffer. 'node_offset'
- is how much we have read from this particular node before and which
- shouldn't be read again. 'max_size' is how much space there is in
- the buffer. */
-static int
-jffs_get_node_data(struct jffs_file *f, struct jffs_node *node,
- unsigned char *buf,__u32 node_offset, __u32 max_size)
-{
- struct jffs_fmcontrol *fmc = f->c->fmc;
- __u32 pos = node->fm->offset + node->fm_offset + node_offset;
- __u32 avail = node->data_size - node_offset;
- __u32 r;
-
- D2(printk(" jffs_get_node_data(): file: \"%s\", ino: %u, "
- "version: %u, node_offset: %u\n",
- f->name, node->ino, node->version, node_offset));
-
- r = min(avail, max_size);
- D3(printk(KERN_NOTICE "jffs_get_node_data\n"));
- flash_safe_read(fmc->mtd, pos, buf, r);
-
- D3(printk(" jffs_get_node_data(): Read %u byte%s.\n",
- r, (r == 1 ? "" : "s")));
-
- return r;
-}
-
-
-/* Read data from the file's nodes. Write the data to the buffer
- 'buf'. 'read_offset' tells how much data we should skip. */
-int
-jffs_read_data(struct jffs_file *f, unsigned char *buf, __u32 read_offset,
- __u32 size)
-{
- struct jffs_node *node;
- __u32 read_data = 0; /* Total amount of read data. */
- __u32 node_offset = 0;
- __u32 pos = 0; /* Number of bytes traversed. */
-
- D2(printk("jffs_read_data(): file = \"%s\", read_offset = %d, "
- "size = %u\n",
- (f->name ? f->name : ""), read_offset, size));
-
- if (read_offset >= f->size) {
- D(printk(" f->size: %d\n", f->size));
- return 0;
- }
-
- /* First find the node to read data from. */
- node = f->range_head;
- while (pos <= read_offset) {
- node_offset = read_offset - pos;
- if (node_offset >= node->data_size) {
- pos += node->data_size;
- node = node->range_next;
- }
- else {
- break;
- }
- }
-
- /* "Cats are living proof that not everything in nature
- has to be useful."
- - Garrison Keilor ('97) */
-
- /* Fill the buffer. */
- while (node && (read_data < size)) {
- int r;
- if (!node->fm) {
- /* This node does not refer to real data. */
- r = min(size - read_data,
- node->data_size - node_offset);
- memset(&buf[read_data], 0, r);
- }
- else if ((r = jffs_get_node_data(f, node, &buf[read_data],
- node_offset,
- size - read_data)) < 0) {
- return r;
- }
- read_data += r;
- node_offset = 0;
- node = node->range_next;
- }
- D3(printk(" jffs_read_data(): Read %u bytes.\n", read_data));
- return read_data;
-}
-
-
-/* Used for traversing all nodes in the hash table. */
-int
-jffs_foreach_file(struct jffs_control *c, int (*func)(struct jffs_file *))
-{
- int pos;
- int r;
- int result = 0;
-
- for (pos = 0; pos < c->hash_len; pos++) {
- struct jffs_file *f, *next;
-
- /* We must do _safe, because 'func' might remove the
- current file 'f' from the list. */
- list_for_each_entry_safe(f, next, &c->hash[pos], hash) {
- r = func(f);
- if (r < 0)
- return r;
- result += r;
- }
- }
-
- return result;
-}
-
-
-/* Free all nodes associated with a file. */
-static int
-jffs_free_node_list(struct jffs_file *f)
-{
- struct jffs_node *node;
- struct jffs_node *p;
-
- D3(printk("jffs_free_node_list(): f #%u, \"%s\"\n",
- f->ino, (f->name ? f->name : "")));
- node = f->version_head;
- while (node) {
- p = node;
- node = node->version_next;
- jffs_free_node(p);
- DJM(no_jffs_node--);
- }
- return 0;
-}
-
-
-/* Free a file and its name. */
-static int
-jffs_free_file(struct jffs_file *f)
-{
- D3(printk("jffs_free_file: f #%u, \"%s\"\n",
- f->ino, (f->name ? f->name : "")));
-
- if (f->name) {
- kfree(f->name);
- DJM(no_name--);
- }
- kfree(f);
- no_jffs_file--;
- return 0;
-}
-
-static long
-jffs_get_file_count(void)
-{
- return no_jffs_file;
-}
-
-/* See if a file is deleted. If so, mark that file's nodes as obsolete. */
-int
-jffs_possibly_delete_file(struct jffs_file *f)
-{
- struct jffs_node *n;
-
- D3(printk("jffs_possibly_delete_file(): ino: %u\n",
- f->ino));
-
- ASSERT(if (!f) {
- printk(KERN_ERR "jffs_possibly_delete_file(): f == NULL\n");
- return -1;
- });
-
- if (f->deleted) {
- /* First try to remove all older versions. Commence with
- the oldest node. */
- for (n = f->version_head; n; n = n->version_next) {
- if (!n->fm) {
- continue;
- }
- if (jffs_fmfree(f->c->fmc, n->fm, n) < 0) {
- break;
- }
- }
- /* Unlink the file from the filesystem. */
- if (!f->c->building_fs) {
- jffs_unlink_file_from_tree(f);
- }
- jffs_unlink_file_from_hash(f);
- jffs_free_node_list(f);
- jffs_free_file(f);
- }
- return 0;
-}
-
-
-/* Used in conjunction with jffs_foreach_file() to count the number
- of files in the file system. */
-int
-jffs_file_count(struct jffs_file *f)
-{
- return 1;
-}
-
-
-/* Build up a file's range list from scratch by going through the
- version list. */
-static int
-jffs_build_file(struct jffs_file *f)
-{
- struct jffs_node *n;
-
- D3(printk("jffs_build_file(): ino: %u, name: \"%s\"\n",
- f->ino, (f->name ? f->name : "")));
-
- for (n = f->version_head; n; n = n->version_next) {
- jffs_update_file(f, n);
- }
- return 0;
-}
-
-
-/* Remove an amount of data from a file. If this amount of data is
- zero, that could mean that a node should be split in two parts.
- We remove or change the appropriate nodes in the lists.
-
- Starting offset of area to be removed is node->data_offset,
- and the length of the area is in node->removed_size. */
-static int
-jffs_delete_data(struct jffs_file *f, struct jffs_node *node)
-{
- struct jffs_node *n;
- __u32 offset = node->data_offset;
- __u32 remove_size = node->removed_size;
-
- D3(printk("jffs_delete_data(): offset = %u, remove_size = %u\n",
- offset, remove_size));
-
- if (remove_size == 0
- && f->range_tail
- && f->range_tail->data_offset + f->range_tail->data_size
- == offset) {
- /* A simple append; nothing to remove or no node to split. */
- return 0;
- }
-
- /* Find the node where we should begin the removal. */
- for (n = f->range_head; n; n = n->range_next) {
- if (n->data_offset + n->data_size > offset) {
- break;
- }
- }
- if (!n) {
- /* If there's no data in the file there's no data to
- remove either. */
- return 0;
- }
-
- if (n->data_offset > offset) {
- /* XXX: Not implemented yet. */
- printk(KERN_WARNING "JFFS: An unexpected situation "
- "occurred in jffs_delete_data.\n");
- }
- else if (n->data_offset < offset) {
- /* See if the node has to be split into two parts. */
- if (n->data_offset + n->data_size > offset + remove_size) {
- /* Do the split. */
- struct jffs_node *new_node;
- D3(printk("jffs_delete_data(): Split node with "
- "version number %u.\n", n->version));
-
- if (!(new_node = jffs_alloc_node())) {
- D(printk("jffs_delete_data(): -ENOMEM\n"));
- return -ENOMEM;
- }
- DJM(no_jffs_node++);
-
- new_node->ino = n->ino;
- new_node->version = n->version;
- new_node->data_offset = offset;
- new_node->data_size = n->data_size - (remove_size + (offset - n->data_offset));
- new_node->fm_offset = n->fm_offset + (remove_size + (offset - n->data_offset));
- new_node->name_size = n->name_size;
- new_node->fm = n->fm;
- new_node->version_prev = n;
- new_node->version_next = n->version_next;
- if (new_node->version_next) {
- new_node->version_next->version_prev
- = new_node;
- }
- else {
- f->version_tail = new_node;
- }
- n->version_next = new_node;
- new_node->range_prev = n;
- new_node->range_next = n->range_next;
- if (new_node->range_next) {
- new_node->range_next->range_prev = new_node;
- }
- else {
- f->range_tail = new_node;
- }
- /* A very interesting can of worms. */
- n->range_next = new_node;
- n->data_size = offset - n->data_offset;
- if (new_node->fm)
- jffs_add_node(new_node);
- else {
- D1(printk(KERN_WARNING "jffs_delete_data(): Splitting an empty node (file hold).\n!"));
- D1(printk(KERN_WARNING "FIXME: Did dwmw2 do the right thing here?\n"));
- }
- n = new_node->range_next;
- remove_size = 0;
- }
- else {
- /* No. No need to split the node. Just remove
- the end of the node. */
- int r = min(n->data_offset + n->data_size
- - offset, remove_size);
- n->data_size -= r;
- remove_size -= r;
- n = n->range_next;
- }
- }
-
- /* Remove as many nodes as necessary. */
- while (n && remove_size) {
- if (n->data_size <= remove_size) {
- struct jffs_node *p = n;
- remove_size -= n->data_size;
- n = n->range_next;
- D3(printk("jffs_delete_data(): Removing node: "
- "ino: %u, version: %u%s\n",
- p->ino, p->version,
- (p->fm ? "" : " (virtual)")));
- if (p->fm) {
- jffs_fmfree(f->c->fmc, p->fm, p);
- }
- jffs_unlink_node_from_range_list(f, p);
- jffs_unlink_node_from_version_list(f, p);
- jffs_free_node(p);
- DJM(no_jffs_node--);
- }
- else {
- n->data_size -= remove_size;
- n->fm_offset += remove_size;
- n->data_offset -= (node->removed_size - remove_size);
- n = n->range_next;
- break;
- }
- }
-
- /* Adjust the following nodes' information about offsets etc. */
- while (n && node->removed_size) {
- n->data_offset -= node->removed_size;
- n = n->range_next;
- }
-
- if (node->removed_size > (f->size - node->data_offset)) {
- /* It's possible that the removed_size is in fact
- * greater than the amount of data we actually thought
- * were present in the first place - some of the nodes
- * which this node originally obsoleted may already have
- * been deleted from the flash by subsequent garbage
- * collection.
- *
- * If this is the case, don't let f->size go negative.
- * Bad things would happen :)
- */
- f->size = node->data_offset;
- } else {
- f->size -= node->removed_size;
- }
- D3(printk("jffs_delete_data(): f->size = %d\n", f->size));
- return 0;
-} /* jffs_delete_data() */
-
-
-/* Insert some data into a file. Prior to the call to this function,
- jffs_delete_data should be called. */
-static int
-jffs_insert_data(struct jffs_file *f, struct jffs_node *node)
-{
- D3(printk("jffs_insert_data(): node->data_offset = %u, "
- "node->data_size = %u, f->size = %u\n",
- node->data_offset, node->data_size, f->size));
-
- /* Find the position where we should insert data. */
- retry:
- if (node->data_offset == f->size) {
- /* A simple append. This is the most common operation. */
- node->range_next = NULL;
- node->range_prev = f->range_tail;
- if (node->range_prev) {
- node->range_prev->range_next = node;
- }
- f->range_tail = node;
- f->size += node->data_size;
- if (!f->range_head) {
- f->range_head = node;
- }
- }
- else if (node->data_offset < f->size) {
- /* Trying to insert data into the middle of the file. This
- means no problem because jffs_delete_data() has already
- prepared the range list for us. */
- struct jffs_node *n;
-
- /* Find the correct place for the insertion and then insert
- the node. */
- for (n = f->range_head; n; n = n->range_next) {
- D2(printk("Cool stuff's happening!\n"));
-
- if (n->data_offset == node->data_offset) {
- node->range_prev = n->range_prev;
- if (node->range_prev) {
- node->range_prev->range_next = node;
- }
- else {
- f->range_head = node;
- }
- node->range_next = n;
- n->range_prev = node;
- break;
- }
- ASSERT(else if (n->data_offset + n->data_size >
- node->data_offset) {
- printk(KERN_ERR "jffs_insert_data(): "
- "Couldn't find a place to insert "
- "the data!\n");
- return -1;
- });
- }
-
- /* Adjust later nodes' offsets etc. */
- n = node->range_next;
- while (n) {
- n->data_offset += node->data_size;
- n = n->range_next;
- }
- f->size += node->data_size;
- }
- else if (node->data_offset > f->size) {
- /* Okay. This is tricky. This means that we want to insert
- data at a place that is beyond the limits of the file as
- it is constructed right now. This is actually a common
- event that for instance could occur during the mounting
- of the file system if a large file have been truncated,
- rewritten and then only partially garbage collected. */
-
- struct jffs_node *n;
-
- /* We need a place holder for the data that is missing in
- front of this insertion. This "virtual node" will not
- be associated with any space on the flash device. */
- struct jffs_node *virtual_node;
- if (!(virtual_node = jffs_alloc_node())) {
- return -ENOMEM;
- }
-
- D(printk("jffs_insert_data: Inserting a virtual node.\n"));
- D(printk(" node->data_offset = %u\n", node->data_offset));
- D(printk(" f->size = %u\n", f->size));
-
- virtual_node->ino = node->ino;
- virtual_node->version = node->version;
- virtual_node->removed_size = 0;
- virtual_node->fm_offset = 0;
- virtual_node->name_size = 0;
- virtual_node->fm = NULL; /* This is a virtual data holder. */
- virtual_node->version_prev = NULL;
- virtual_node->version_next = NULL;
- virtual_node->range_next = NULL;
-
- /* Are there any data at all in the file yet? */
- if (f->range_head) {
- virtual_node->data_offset
- = f->range_tail->data_offset
- + f->range_tail->data_size;
- virtual_node->data_size
- = node->data_offset - virtual_node->data_offset;
- virtual_node->range_prev = f->range_tail;
- f->range_tail->range_next = virtual_node;
- }
- else {
- virtual_node->data_offset = 0;
- virtual_node->data_size = node->data_offset;
- virtual_node->range_prev = NULL;
- f->range_head = virtual_node;
- }
-
- f->range_tail = virtual_node;
- f->size += virtual_node->data_size;
-
- /* Insert this virtual node in the version list as well. */
- for (n = f->version_head; n ; n = n->version_next) {
- if (n->version == virtual_node->version) {
- virtual_node->version_prev = n->version_prev;
- n->version_prev = virtual_node;
- if (virtual_node->version_prev) {
- virtual_node->version_prev
- ->version_next = virtual_node;
- }
- else {
- f->version_head = virtual_node;
- }
- virtual_node->version_next = n;
- break;
- }
- }
-
- D(jffs_print_node(virtual_node));
-
- /* Make a new try to insert the node. */
- goto retry;
- }
-
- D3(printk("jffs_insert_data(): f->size = %d\n", f->size));
- return 0;
-}
-
-
-/* A new node (with data) has been added to the file and now the range
- list has to be modified. */
-static int
-jffs_update_file(struct jffs_file *f, struct jffs_node *node)
-{
- int err;
-
- D3(printk("jffs_update_file(): ino: %u, version: %u\n",
- f->ino, node->version));
-
- if (node->data_size == 0) {
- if (node->removed_size == 0) {
- /* data_offset == X */
- /* data_size == 0 */
- /* remove_size == 0 */
- }
- else {
- /* data_offset == X */
- /* data_size == 0 */
- /* remove_size != 0 */
- if ((err = jffs_delete_data(f, node)) < 0) {
- return err;
- }
- }
- }
- else {
- /* data_offset == X */
- /* data_size != 0 */
- /* remove_size == Y */
- if ((err = jffs_delete_data(f, node)) < 0) {
- return err;
- }
- if ((err = jffs_insert_data(f, node)) < 0) {
- return err;
- }
- }
- return 0;
-}
-
-/* Print the contents of a file. */
-#if 0
-int
-jffs_print_file(struct jffs_file *f)
-{
- D(int i);
- D(printk("jffs_file: 0x%p\n", f));
- D(printk("{\n"));
- D(printk(" 0x%08x, /* ino */\n", f->ino));
- D(printk(" 0x%08x, /* pino */\n", f->pino));
- D(printk(" 0x%08x, /* mode */\n", f->mode));
- D(printk(" 0x%04x, /* uid */\n", f->uid));
- D(printk(" 0x%04x, /* gid */\n", f->gid));
- D(printk(" 0x%08x, /* atime */\n", f->atime));
- D(printk(" 0x%08x, /* mtime */\n", f->mtime));
- D(printk(" 0x%08x, /* ctime */\n", f->ctime));
- D(printk(" 0x%02x, /* nsize */\n", f->nsize));
- D(printk(" 0x%02x, /* nlink */\n", f->nlink));
- D(printk(" 0x%02x, /* deleted */\n", f->deleted));
- D(printk(" \"%s\", ", (f->name ? f->name : "")));
- D(for (i = strlen(f->name ? f->name : ""); i < 8; ++i) {
- printk(" ");
- });
- D(printk("/* name */\n"));
- D(printk(" 0x%08x, /* size */\n", f->size));
- D(printk(" 0x%08x, /* highest_version */\n",
- f->highest_version));
- D(printk(" 0x%p, /* c */\n", f->c));
- D(printk(" 0x%p, /* parent */\n", f->parent));
- D(printk(" 0x%p, /* children */\n", f->children));
- D(printk(" 0x%p, /* sibling_prev */\n", f->sibling_prev));
- D(printk(" 0x%p, /* sibling_next */\n", f->sibling_next));
- D(printk(" 0x%p, /* hash_prev */\n", f->hash.prev));
- D(printk(" 0x%p, /* hash_next */\n", f->hash.next));
- D(printk(" 0x%p, /* range_head */\n", f->range_head));
- D(printk(" 0x%p, /* range_tail */\n", f->range_tail));
- D(printk(" 0x%p, /* version_head */\n", f->version_head));
- D(printk(" 0x%p, /* version_tail */\n", f->version_tail));
- D(printk("}\n"));
- return 0;
-}
-#endif /* 0 */
-
-void
-jffs_print_hash_table(struct jffs_control *c)
-{
- int i;
-
- printk("JFFS: Dumping the file system's hash table...\n");
- for (i = 0; i < c->hash_len; i++) {
- struct jffs_file *f;
- list_for_each_entry(f, &c->hash[i], hash) {
- printk("*** c->hash[%u]: \"%s\" "
- "(ino: %u, pino: %u)\n",
- i, (f->name ? f->name : ""),
- f->ino, f->pino);
- }
- }
-}
-
-
-void
-jffs_print_tree(struct jffs_file *first_file, int indent)
-{
- struct jffs_file *f;
- char *space;
- int dir;
-
- if (!first_file) {
- return;
- }
-
- if (!(space = kmalloc(indent + 1, GFP_KERNEL))) {
- printk("jffs_print_tree(): Out of memory!\n");
- return;
- }
-
- memset(space, ' ', indent);
- space[indent] = '\0';
-
- for (f = first_file; f; f = f->sibling_next) {
- dir = S_ISDIR(f->mode);
- printk("%s%s%s (ino: %u, highest_version: %u, size: %u)\n",
- space, (f->name ? f->name : ""), (dir ? "/" : ""),
- f->ino, f->highest_version, f->size);
- if (dir) {
- jffs_print_tree(f->children, indent + 2);
- }
- }
-
- kfree(space);
-}
-
-
-#if defined(JFFS_MEMORY_DEBUG) && JFFS_MEMORY_DEBUG
-void
-jffs_print_memory_allocation_statistics(void)
-{
- static long printout;
- printk("________ Memory printout #%ld ________\n", ++printout);
- printk("no_jffs_file = %ld\n", no_jffs_file);
- printk("no_jffs_node = %ld\n", no_jffs_node);
- printk("no_jffs_control = %ld\n", no_jffs_control);
- printk("no_jffs_raw_inode = %ld\n", no_jffs_raw_inode);
- printk("no_jffs_node_ref = %ld\n", no_jffs_node_ref);
- printk("no_jffs_fm = %ld\n", no_jffs_fm);
- printk("no_jffs_fmcontrol = %ld\n", no_jffs_fmcontrol);
- printk("no_hash = %ld\n", no_hash);
- printk("no_name = %ld\n", no_name);
- printk("\n");
-}
-#endif
-
-
-/* Rewrite `size' bytes, and begin at `node'. */
-static int
-jffs_rewrite_data(struct jffs_file *f, struct jffs_node *node, __u32 size)
-{
- struct jffs_control *c = f->c;
- struct jffs_fmcontrol *fmc = c->fmc;
- struct jffs_raw_inode raw_inode;
- struct jffs_node *new_node;
- struct jffs_fm *fm;
- __u32 pos;
- __u32 pos_dchksum;
- __u32 total_name_size;
- __u32 total_data_size;
- __u32 total_size;
- int err;
-
- D1(printk("***jffs_rewrite_data(): node: %u, name: \"%s\", size: %u\n",
- f->ino, (f->name ? f->name : "(null)"), size));
-
- /* Create and initialize the new node. */
- if (!(new_node = jffs_alloc_node())) {
- D(printk("jffs_rewrite_data(): "
- "Failed to allocate node.\n"));
- return -ENOMEM;
- }
- DJM(no_jffs_node++);
- new_node->data_offset = node->data_offset;
- new_node->removed_size = size;
- total_name_size = JFFS_PAD(f->nsize);
- total_data_size = JFFS_PAD(size);
- total_size = sizeof(struct jffs_raw_inode)
- + total_name_size + total_data_size;
- new_node->fm_offset = sizeof(struct jffs_raw_inode)
- + total_name_size;
-
-retry:
- jffs_fm_write_lock(fmc);
- err = 0;
-
- if ((err = jffs_fmalloc(fmc, total_size, new_node, &fm)) < 0) {
- DJM(no_jffs_node--);
- jffs_fm_write_unlock(fmc);
- D(printk("jffs_rewrite_data(): Failed to allocate fm.\n"));
- jffs_free_node(new_node);
- return err;
- }
- else if (!fm->nodes) {
- /* The jffs_fm struct that we got is not big enough. */
- /* This should never happen, because we deal with this case
- in jffs_garbage_collect_next().*/
- printk(KERN_WARNING "jffs_rewrite_data(): Allocated node is too small (%d bytes of %d)\n", fm->size, total_size);
- if ((err = jffs_write_dummy_node(c, fm)) < 0) {
- D(printk("jffs_rewrite_data(): "
- "jffs_write_dummy_node() Failed!\n"));
- } else {
- err = -ENOSPC;
- }
- DJM(no_jffs_fm--);
- jffs_fm_write_unlock(fmc);
- kfree(fm);
-
- return err;
- }
- new_node->fm = fm;
-
- /* Initialize the raw inode. */
- raw_inode.magic = JFFS_MAGIC_BITMASK;
- raw_inode.ino = f->ino;
- raw_inode.pino = f->pino;
- raw_inode.version = f->highest_version + 1;
- raw_inode.mode = f->mode;
- raw_inode.uid = f->uid;
- raw_inode.gid = f->gid;
- raw_inode.atime = f->atime;
- raw_inode.mtime = f->mtime;
- raw_inode.ctime = f->ctime;
- raw_inode.offset = node->data_offset;
- raw_inode.dsize = size;
- raw_inode.rsize = size;
- raw_inode.nsize = f->nsize;
- raw_inode.nlink = f->nlink;
- raw_inode.spare = 0;
- raw_inode.rename = 0;
- raw_inode.deleted = f->deleted;
- raw_inode.accurate = 0xff;
- raw_inode.dchksum = 0;
- raw_inode.nchksum = 0;
-
- pos = new_node->fm->offset;
- pos_dchksum = pos +JFFS_RAW_INODE_DCHKSUM_OFFSET;
-
- D3(printk("jffs_rewrite_data(): Writing this raw inode "
- "to pos 0x%ul.\n", pos));
- D3(jffs_print_raw_inode(&raw_inode));
-
- if ((err = flash_safe_write(fmc->mtd, pos,
- (u_char *) &raw_inode,
- sizeof(struct jffs_raw_inode)
- - sizeof(__u32)
- - sizeof(__u16) - sizeof(__u16))) < 0) {
- jffs_fmfree_partly(fmc, fm,
- total_name_size + total_data_size);
- jffs_fm_write_unlock(fmc);
- printk(KERN_ERR "JFFS: jffs_rewrite_data: Write error during "
- "rewrite. (raw inode)\n");
- printk(KERN_ERR "JFFS: jffs_rewrite_data: Now retrying "
- "rewrite. (raw inode)\n");
- goto retry;
- }
- pos += sizeof(struct jffs_raw_inode);
-
- /* Write the name to the flash memory. */
- if (f->nsize) {
- D3(printk("jffs_rewrite_data(): Writing name \"%s\" to "
- "pos 0x%ul.\n", f->name, (unsigned int) pos));
- if ((err = flash_safe_write(fmc->mtd, pos,
- (u_char *)f->name,
- f->nsize)) < 0) {
- jffs_fmfree_partly(fmc, fm, total_data_size);
- jffs_fm_write_unlock(fmc);
- printk(KERN_ERR "JFFS: jffs_rewrite_data: Write "
- "error during rewrite. (name)\n");
- printk(KERN_ERR "JFFS: jffs_rewrite_data: Now retrying "
- "rewrite. (name)\n");
- goto retry;
- }
- pos += total_name_size;
- raw_inode.nchksum = jffs_checksum(f->name, f->nsize);
- }
-
- /* Write the data. */
- if (size) {
- int r;
- unsigned char *page;
- __u32 offset = node->data_offset;
-
- if (!(page = (unsigned char *)__get_free_page(GFP_KERNEL))) {
- jffs_fmfree_partly(fmc, fm, 0);
- return -1;
- }
-
- while (size) {
- __u32 s = min(size, (__u32)PAGE_SIZE);
- if ((r = jffs_read_data(f, (char *)page,
- offset, s)) < s) {
- free_page((unsigned long)page);
- jffs_fmfree_partly(fmc, fm, 0);
- jffs_fm_write_unlock(fmc);
- printk(KERN_ERR "JFFS: jffs_rewrite_data: "
- "jffs_read_data() "
- "failed! (r = %d)\n", r);
- return -1;
- }
- if ((err = flash_safe_write(fmc->mtd,
- pos, page, r)) < 0) {
- free_page((unsigned long)page);
- jffs_fmfree_partly(fmc, fm, 0);
- jffs_fm_write_unlock(fmc);
- printk(KERN_ERR "JFFS: jffs_rewrite_data: "
- "Write error during rewrite. "
- "(data)\n");
- goto retry;
- }
- pos += r;
- size -= r;
- offset += r;
- raw_inode.dchksum += jffs_checksum(page, r);
- }
-
- free_page((unsigned long)page);
- }
-
- raw_inode.accurate = 0;
- raw_inode.chksum = jffs_checksum(&raw_inode,
- sizeof(struct jffs_raw_inode)
- - sizeof(__u16));
-
- /* Add the checksum. */
- if ((err
- = flash_safe_write(fmc->mtd, pos_dchksum,
- &((u_char *)
- &raw_inode)[JFFS_RAW_INODE_DCHKSUM_OFFSET],
- sizeof(__u32) + sizeof(__u16)
- + sizeof(__u16))) < 0) {
- jffs_fmfree_partly(fmc, fm, 0);
- jffs_fm_write_unlock(fmc);
- printk(KERN_ERR "JFFS: jffs_rewrite_data: Write error during "
- "rewrite. (checksum)\n");
- goto retry;
- }
-
- /* Now make the file system aware of the newly written node. */
- jffs_insert_node(c, f, &raw_inode, f->name, new_node);
- jffs_fm_write_unlock(fmc);
-
- D3(printk("jffs_rewrite_data(): Leaving...\n"));
- return 0;
-} /* jffs_rewrite_data() */
-
-
-/* jffs_garbage_collect_next implements one step in the garbage collect
- process and is often called multiple times at each occasion of a
- garbage collect. */
-
-static int
-jffs_garbage_collect_next(struct jffs_control *c)
-{
- struct jffs_fmcontrol *fmc = c->fmc;
- struct jffs_node *node;
- struct jffs_file *f;
- int err = 0;
- __u32 size;
- __u32 data_size;
- __u32 total_name_size;
- __u32 extra_available;
- __u32 space_needed;
- __u32 free_chunk_size1 = jffs_free_size1(fmc);
- D2(__u32 free_chunk_size2 = jffs_free_size2(fmc));
-
- /* Get the oldest node in the flash. */
- node = jffs_get_oldest_node(fmc);
- ASSERT(if (!node) {
- printk(KERN_ERR "JFFS: jffs_garbage_collect_next: "
- "No oldest node found!\n");
- err = -1;
- goto jffs_garbage_collect_next_end;
-
-
- });
-
- /* Find its corresponding file too. */
- f = jffs_find_file(c, node->ino);
-
- if (!f) {
- printk (KERN_ERR "JFFS: jffs_garbage_collect_next: "
- "No file to garbage collect! "
- "(ino = 0x%08x)\n", node->ino);
- /* FIXME: Free the offending node and recover. */
- err = -1;
- goto jffs_garbage_collect_next_end;
- }
-
- /* We always write out the name. Theoretically, we don't need
- to, but for now it's easier - because otherwise we'd have
- to keep track of how many times the current name exists on
- the flash and make sure it never reaches zero.
-
- The current approach means that would be possible to cause
- the GC to end up eating its tail by writing lots of nodes
- with no name for it to garbage-collect. Hence the change in
- inode.c to write names with _every_ node.
-
- It sucks, but it _should_ work.
- */
- total_name_size = JFFS_PAD(f->nsize);
-
- D1(printk("jffs_garbage_collect_next(): \"%s\", "
- "ino: %u, version: %u, location 0x%x, dsize %u\n",
- (f->name ? f->name : ""), node->ino, node->version,
- node->fm->offset, node->data_size));
-
- /* Compute how many data it's possible to rewrite at the moment. */
- data_size = f->size - node->data_offset;
-
- /* And from that, the total size of the chunk we want to write */
- size = sizeof(struct jffs_raw_inode) + total_name_size
- + data_size + JFFS_GET_PAD_BYTES(data_size);
-
- /* If that's more than max_chunk_size, reduce it accordingly */
- if (size > fmc->max_chunk_size) {
- size = fmc->max_chunk_size;
- data_size = size - sizeof(struct jffs_raw_inode)
- - total_name_size;
- }
-
- /* If we're asking to take up more space than free_chunk_size1
- but we _could_ fit in it, shrink accordingly.
- */
- if (size > free_chunk_size1) {
-
- if (free_chunk_size1 <
- (sizeof(struct jffs_raw_inode) + total_name_size + BLOCK_SIZE)){
- /* The space left is too small to be of any
- use really. */
- struct jffs_fm *dirty_fm
- = jffs_fmalloced(fmc,
- fmc->tail->offset + fmc->tail->size,
- free_chunk_size1, NULL);
- if (!dirty_fm) {
- printk(KERN_ERR "JFFS: "
- "jffs_garbage_collect_next: "
- "Failed to allocate `dirty' "
- "flash memory!\n");
- err = -1;
- goto jffs_garbage_collect_next_end;
- }
- D1(printk("Dirtying end of flash - too small\n"));
- jffs_write_dummy_node(c, dirty_fm);
- err = 0;
- goto jffs_garbage_collect_next_end;
- }
- D1(printk("Reducing size of new node from %d to %d to avoid "
- " exceeding free_chunk_size1\n",
- size, free_chunk_size1));
-
- size = free_chunk_size1;
- data_size = size - sizeof(struct jffs_raw_inode)
- - total_name_size;
- }
-
-
- /* Calculate the amount of space needed to hold the nodes
- which are remaining in the tail */
- space_needed = fmc->min_free_size - (node->fm->offset % fmc->sector_size);
-
- /* From that, calculate how much 'extra' space we can use to
- increase the size of the node we're writing from the size
- of the node we're obsoleting
- */
- if (space_needed > fmc->free_size) {
- /* If we've gone below min_free_size for some reason,
- don't fuck up. This is why we have
- min_free_size > sector_size. Whinge about it though,
- just so I can convince myself my maths is right.
- */
- D1(printk(KERN_WARNING "jffs_garbage_collect_next(): "
- "space_needed %d exceeded free_size %d\n",
- space_needed, fmc->free_size));
- extra_available = 0;
- } else {
- extra_available = fmc->free_size - space_needed;
- }
-
- /* Check that we don't use up any more 'extra' space than
- what's available */
- if (size > JFFS_PAD(node->data_size) + total_name_size +
- sizeof(struct jffs_raw_inode) + extra_available) {
- D1(printk("Reducing size of new node from %d to %ld to avoid "
- "catching our tail\n", size,
- (long) (JFFS_PAD(node->data_size) + JFFS_PAD(node->name_size) +
- sizeof(struct jffs_raw_inode) + extra_available)));
- D1(printk("space_needed = %d, extra_available = %d\n",
- space_needed, extra_available));
-
- size = JFFS_PAD(node->data_size) + total_name_size +
- sizeof(struct jffs_raw_inode) + extra_available;
- data_size = size - sizeof(struct jffs_raw_inode)
- - total_name_size;
- };
-
- D2(printk(" total_name_size: %u\n", total_name_size));
- D2(printk(" data_size: %u\n", data_size));
- D2(printk(" size: %u\n", size));
- D2(printk(" f->nsize: %u\n", f->nsize));
- D2(printk(" f->size: %u\n", f->size));
- D2(printk(" node->data_offset: %u\n", node->data_offset));
- D2(printk(" free_chunk_size1: %u\n", free_chunk_size1));
- D2(printk(" free_chunk_size2: %u\n", free_chunk_size2));
- D2(printk(" node->fm->offset: 0x%08x\n", node->fm->offset));
-
- if ((err = jffs_rewrite_data(f, node, data_size))) {
- printk(KERN_WARNING "jffs_rewrite_data() failed: %d\n", err);
- return err;
- }
-
-jffs_garbage_collect_next_end:
- D3(printk("jffs_garbage_collect_next: Leaving...\n"));
- return err;
-} /* jffs_garbage_collect_next */
-
-
-/* If an obsolete node is partly going to be erased due to garbage
- collection, the part that isn't going to be erased must be filled
- with zeroes so that the scan of the flash will work smoothly next
- time. (The data in the file could for instance be a JFFS image
- which could cause enormous confusion during a scan of the flash
- device if we didn't do this.)
- There are two phases in this procedure: First, the clearing of
- the name and data parts of the node. Second, possibly also clearing
- a part of the raw inode as well. If the box is power cycled during
- the first phase, only the checksum of this node-to-be-cleared-at-
- the-end will be wrong. If the box is power cycled during, or after,
- the clearing of the raw inode, the information like the length of
- the name and data parts are zeroed. The next time the box is
- powered up, the scanning algorithm manages this faulty data too
- because:
-
- - The checksum is invalid and thus the raw inode must be discarded
- in any case.
- - If the lengths of the data part or the name part are zeroed, the
- scanning just continues after the raw inode. But after the inode
- the scanning procedure just finds zeroes which is the same as
- dirt.
-
- So, in the end, this could never fail. :-) Even if it does fail,
- the scanning algorithm should manage that too. */
-
-static int
-jffs_clear_end_of_node(struct jffs_control *c, __u32 erase_size)
-{
- struct jffs_fm *fm;
- struct jffs_fmcontrol *fmc = c->fmc;
- __u32 zero_offset;
- __u32 zero_size;
- __u32 zero_offset_data;
- __u32 zero_size_data;
- __u32 cutting_raw_inode = 0;
-
- if (!(fm = jffs_cut_node(fmc, erase_size))) {
- D3(printk("jffs_clear_end_of_node(): fm == NULL\n"));
- return 0;
- }
-
- /* Where and how much shall we clear? */
- zero_offset = fmc->head->offset + erase_size;
- zero_size = fm->offset + fm->size - zero_offset;
-
- /* Do we have to clear the raw_inode explicitly? */
- if (fm->size - zero_size < sizeof(struct jffs_raw_inode)) {
- cutting_raw_inode = sizeof(struct jffs_raw_inode)
- - (fm->size - zero_size);
- }
-
- /* First, clear the name and data fields. */
- zero_offset_data = zero_offset + cutting_raw_inode;
- zero_size_data = zero_size - cutting_raw_inode;
- flash_safe_acquire(fmc->mtd);
- flash_memset(fmc->mtd, zero_offset_data, 0, zero_size_data);
- flash_safe_release(fmc->mtd);
-
- /* Should we clear a part of the raw inode? */
- if (cutting_raw_inode) {
- /* I guess it is ok to clear the raw inode in this order. */
- flash_safe_acquire(fmc->mtd);
- flash_memset(fmc->mtd, zero_offset, 0,
- cutting_raw_inode);
- flash_safe_release(fmc->mtd);
- }
-
- return 0;
-} /* jffs_clear_end_of_node() */
-
-/* Try to erase as much as possible of the dirt in the flash memory. */
-static long
-jffs_try_to_erase(struct jffs_control *c)
-{
- struct jffs_fmcontrol *fmc = c->fmc;
- long erase_size;
- int err;
- __u32 offset;
-
- D3(printk("jffs_try_to_erase()\n"));
-
- erase_size = jffs_erasable_size(fmc);
-
- D2(printk("jffs_try_to_erase(): erase_size = %ld\n", erase_size));
-
- if (erase_size == 0) {
- return 0;
- }
- else if (erase_size < 0) {
- printk(KERN_ERR "JFFS: jffs_try_to_erase: "
- "jffs_erasable_size returned %ld.\n", erase_size);
- return erase_size;
- }
-
- if ((err = jffs_clear_end_of_node(c, erase_size)) < 0) {
- printk(KERN_ERR "JFFS: jffs_try_to_erase: "
- "Clearing of node failed.\n");
- return err;
- }
-
- offset = fmc->head->offset;
-
- /* Now, let's try to do the erase. */
- if ((err = flash_erase_region(fmc->mtd,
- offset, erase_size)) < 0) {
- printk(KERN_ERR "JFFS: Erase of flash failed. "
- "offset = %u, erase_size = %ld\n",
- offset, erase_size);
- /* XXX: Here we should allocate this area as dirty
- with jffs_fmalloced or something similar. Now
- we just report the error. */
- return err;
- }
-
-#if 0
- /* Check if the erased sectors really got erased. */
- {
- __u32 pos;
- __u32 end;
-
- pos = (__u32)flash_get_direct_pointer(to_kdev_t(c->sb->s_dev), offset);
- end = pos + erase_size;
-
- D2(printk("JFFS: Checking erased sector(s)...\n"));
-
- flash_safe_acquire(fmc->mtd);
-
- for (; pos < end; pos += 4) {
- if (*(__u32 *)pos != JFFS_EMPTY_BITMASK) {
- printk("JFFS: Erase failed! pos = 0x%lx\n",
- (long)pos);
- jffs_hexdump(fmc->mtd, pos,
- jffs_min(256, end - pos));
- err = -1;
- break;
- }
- }
-
- flash_safe_release(fmc->mtd);
-
- if (!err) {
- D2(printk("JFFS: Erase succeeded.\n"));
- }
- else {
- /* XXX: Here we should allocate the memory
- with jffs_fmalloced() in order to prevent
- JFFS from using this area accidentally. */
- return err;
- }
- }
-#endif
-
- /* Update the flash memory data structures. */
- jffs_sync_erase(fmc, erase_size);
-
- return erase_size;
-}
-
-
-/* There are different criteria that should trigger a garbage collect:
-
- 1. There is too much dirt in the memory.
- 2. The free space is becoming small.
- 3. There are many versions of a node.
-
- The garbage collect should always be done in a manner that guarantees
- that future garbage collects cannot be locked. E.g. Rewritten chunks
- should not be too large (span more than one sector in the flash memory
- for exemple). Of course there is a limit on how intelligent this garbage
- collection can be. */
-
-
-static int
-jffs_garbage_collect_now(struct jffs_control *c)
-{
- struct jffs_fmcontrol *fmc = c->fmc;
- long erased = 0;
- int result = 0;
- D1(int i = 1);
- D2(printk("***jffs_garbage_collect_now(): fmc->dirty_size = %u, fmc->free_size = 0x%x\n, fcs1=0x%x, fcs2=0x%x",
- fmc->dirty_size, fmc->free_size, jffs_free_size1(fmc), jffs_free_size2(fmc)));
- D2(jffs_print_fmcontrol(fmc));
-
- // down(&fmc->gclock);
-
- /* If it is possible to garbage collect, do so. */
-
- while (erased == 0) {
- D1(printk("***jffs_garbage_collect_now(): round #%u, "
- "fmc->dirty_size = %u\n", i++, fmc->dirty_size));
- D2(jffs_print_fmcontrol(fmc));
-
- if ((erased = jffs_try_to_erase(c)) < 0) {
- printk(KERN_WARNING "JFFS: Error in "
- "garbage collector.\n");
- result = erased;
- goto gc_end;
- }
- if (erased)
- break;
-
- if (fmc->free_size == 0) {
- /* Argh */
- printk(KERN_ERR "jffs_garbage_collect_now(): free_size == 0. This is BAD.\n");
- result = -ENOSPC;
- break;
- }
-
- if (fmc->dirty_size < fmc->sector_size) {
- /* Actually, we _may_ have been able to free some,
- * if there are many overlapping nodes which aren't
- * actually marked dirty because they still have
- * some valid data in each.
- */
- result = -ENOSPC;
- break;
- }
-
- /* Let's dare to make a garbage collect. */
- if ((result = jffs_garbage_collect_next(c)) < 0) {
- printk(KERN_ERR "JFFS: Something "
- "has gone seriously wrong "
- "with a garbage collect.\n");
- goto gc_end;
- }
-
- D1(printk(" jffs_garbage_collect_now(): erased: %ld\n", erased));
- DJM(jffs_print_memory_allocation_statistics());
- }
-
-gc_end:
- // up(&fmc->gclock);
-
- D3(printk(" jffs_garbage_collect_now(): Leaving...\n"));
- D1(if (erased) {
- printk("jffs_g_c_now(): erased = %ld\n", erased);
- jffs_print_fmcontrol(fmc);
- });
-
- if (!erased && !result)
- return -ENOSPC;
-
- return result;
-} /* jffs_garbage_collect_now() */
-
-
-/* Determine if it is reasonable to start garbage collection.
- We start a gc pass if either:
- - The number of free bytes < MIN_FREE_BYTES && at least one
- block is dirty, OR
- - The number of dirty bytes > MAX_DIRTY_BYTES
-*/
-static inline int thread_should_wake (struct jffs_control *c)
-{
- D1(printk (KERN_NOTICE "thread_should_wake(): free=%d, dirty=%d, blocksize=%d.\n",
- c->fmc->free_size, c->fmc->dirty_size, c->fmc->sector_size));
-
- /* If there's not enough dirty space to free a block, there's no point. */
- if (c->fmc->dirty_size < c->fmc->sector_size) {
- D2(printk(KERN_NOTICE "thread_should_wake(): Not waking. Insufficient dirty space\n"));
- return 0;
- }
-#if 1
- /* If there is too much RAM used by the various structures, GC */
- if (jffs_get_node_inuse() > (c->fmc->used_size/c->fmc->max_chunk_size * 5 + jffs_get_file_count() * 2 + 50)) {
- /* FIXME: Provide proof that this test can be satisfied. We
- don't want a filesystem doing endless GC just because this
- condition cannot ever be false.
- */
- D2(printk(KERN_NOTICE "thread_should_wake(): Waking due to number of nodes\n"));
- return 1;
- }
-#endif
- /* If there are fewer free bytes than the threshold, GC */
- if (c->fmc->free_size < c->gc_minfree_threshold) {
- D2(printk(KERN_NOTICE "thread_should_wake(): Waking due to insufficent free space\n"));
- return 1;
- }
- /* If there are more dirty bytes than the threshold, GC */
- if (c->fmc->dirty_size > c->gc_maxdirty_threshold) {
- D2(printk(KERN_NOTICE "thread_should_wake(): Waking due to excessive dirty space\n"));
- return 1;
- }
- /* FIXME: What about the "There are many versions of a node" condition? */
-
- return 0;
-}
-
-
-void jffs_garbage_collect_trigger(struct jffs_control *c)
-{
- /* NOTE: We rely on the fact that we have the BKL here.
- * Otherwise, the gc_task could go away between the check
- * and the wake_up_process()
- */
- if (c->gc_task && thread_should_wake(c))
- send_sig(SIGHUP, c->gc_task, 1);
-}
-
-
-/* Kernel threads take (void *) as arguments. Thus we pass
- the jffs_control data as a (void *) and then cast it. */
-int
-jffs_garbage_collect_thread(void *ptr)
-{
- struct jffs_control *c = (struct jffs_control *) ptr;
- struct jffs_fmcontrol *fmc = c->fmc;
- long erased;
- int result = 0;
- D1(int i = 1);
-
- daemonize("jffs_gcd");
-
- c->gc_task = current;
-
- lock_kernel();
- init_completion(&c->gc_thread_comp); /* barrier */
- spin_lock_irq(&current->sighand->siglock);
- siginitsetinv (&current->blocked, sigmask(SIGHUP) | sigmask(SIGKILL) | sigmask(SIGSTOP) | sigmask(SIGCONT));
- recalc_sigpending();
- spin_unlock_irq(&current->sighand->siglock);
-
- D1(printk (KERN_NOTICE "jffs_garbage_collect_thread(): Starting infinite loop.\n"));
-
- for (;;) {
-
- /* See if we need to start gc. If we don't, go to sleep.
-
- Current implementation is a BAD THING(tm). If we try
- to unmount the FS, the unmount operation will sleep waiting
- for this thread to exit. We need to arrange to send it a
- sig before the umount process sleeps.
- */
-
- if (!thread_should_wake(c))
- set_current_state (TASK_INTERRUPTIBLE);
-
- schedule(); /* Yes, we do this even if we want to go
- on immediately - we're a low priority
- background task. */
-
- /* Put_super will send a SIGKILL and then wait on the sem.
- */
- while (signal_pending(current)) {
- siginfo_t info;
- unsigned long signr = 0;
-
- if (try_to_freeze())
- continue;
-
- spin_lock_irq(&current->sighand->siglock);
- signr = dequeue_signal(current, &current->blocked, &info);
- spin_unlock_irq(&current->sighand->siglock);
-
- switch(signr) {
- case SIGSTOP:
- D1(printk("jffs_garbage_collect_thread(): SIGSTOP received.\n"));
- set_current_state(TASK_STOPPED);
- schedule();
- break;
-
- case SIGKILL:
- D1(printk("jffs_garbage_collect_thread(): SIGKILL received.\n"));
- c->gc_task = NULL;
- complete_and_exit(&c->gc_thread_comp, 0);
- }
- }
-
-
- D1(printk (KERN_NOTICE "jffs_garbage_collect_thread(): collecting.\n"));
-
- D3(printk (KERN_NOTICE "g_c_thread(): down biglock\n"));
- mutex_lock(&fmc->biglock);
-
- D1(printk("***jffs_garbage_collect_thread(): round #%u, "
- "fmc->dirty_size = %u\n", i++, fmc->dirty_size));
- D2(jffs_print_fmcontrol(fmc));
-
- if ((erased = jffs_try_to_erase(c)) < 0) {
- printk(KERN_WARNING "JFFS: Error in "
- "garbage collector: %ld.\n", erased);
- }
-
- if (erased)
- goto gc_end;
-
- if (fmc->free_size == 0) {
- /* Argh. Might as well commit suicide. */
- printk(KERN_ERR "jffs_garbage_collect_thread(): free_size == 0. This is BAD.\n");
- send_sig(SIGQUIT, c->gc_task, 1);
- // panic()
- goto gc_end;
- }
-
- /* Let's dare to make a garbage collect. */
- if ((result = jffs_garbage_collect_next(c)) < 0) {
- printk(KERN_ERR "JFFS: Something "
- "has gone seriously wrong "
- "with a garbage collect: %d\n", result);
- }
-
- gc_end:
- D3(printk (KERN_NOTICE "g_c_thread(): up biglock\n"));
- mutex_unlock(&fmc->biglock);
- } /* for (;;) */
-} /* jffs_garbage_collect_thread() */