| /* |
| * 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() */ |