diff options
Diffstat (limited to 'fs/jffs/intrep.c')
| -rw-r--r-- | fs/jffs/intrep.c | 3449 |
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(¤t->sighand->siglock); - siginitsetinv (¤t->blocked, sigmask(SIGHUP) | sigmask(SIGKILL) | sigmask(SIGSTOP) | sigmask(SIGCONT)); - recalc_sigpending(); - spin_unlock_irq(¤t->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(¤t->sighand->siglock); - signr = dequeue_signal(current, ¤t->blocked, &info); - spin_unlock_irq(¤t->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() */ |