Mercurial > ecos
diff packages/fs/jffs2/current/src/build.c @ 208:e0c0827131d1 ecos
Merge from eCos master repository on 2002-05-20-20:11:54-BST
| author | jlarmour |
|---|---|
| date | Mon, 20 May 2002 22:19:26 +0000 |
| parents | |
| children | a7947d436e85 |
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new file mode 100644 --- /dev/null +++ b/packages/fs/jffs2/current/src/build.c @@ -0,0 +1,283 @@ +/* + * JFFS2 -- Journalling Flash File System, Version 2. + * + * Copyright (C) 2001, 2002 Red Hat, Inc. + * + * Created by David Woodhouse <dwmw2@cambridge.redhat.com> + * + * For licensing information, see the file 'LICENCE' in this directory. + * + * $Id: build.c,v 1.22 2002/01/09 16:30:57 dwmw2 Exp $ + * + */ + +#ifndef __ECOS +#include <linux/kernel.h> +#include <linux/slab.h> +#endif +#include "nodelist.h" + +int jffs2_build_inode_pass1(struct jffs2_sb_info *, struct jffs2_inode_cache *); +int jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *, struct jffs2_inode_cache *); + + +#define for_each_inode(i, c, ic) for (i=0; i<INOCACHE_HASHSIZE; i++) for (ic=c->inocache_list[i]; ic; ic=ic->next) + +/* Scan plan: + - Scan physical nodes. Build map of inodes/dirents. Allocate inocaches as we go + - Scan directory tree from top down, setting nlink in inocaches + - Scan inocaches for inodes with nlink==0 +*/ +static int jffs2_build_filesystem(struct jffs2_sb_info *c) +{ + int ret; + int i; + struct jffs2_inode_cache *ic; + + /* First, scan the medium and build all the inode caches with + lists of physical nodes */ + ret = jffs2_scan_medium(c); + if (ret) + return ret; + + D1(printk(KERN_DEBUG "Scanned flash completely\n")); + /* Now build the data map for each inode, marking obsoleted nodes + as such, and also increase nlink of any children. */ + for_each_inode(i, c, ic) { + D1(printk(KERN_DEBUG "Pass 1: ino #%u\n", ic->ino)); + ret = jffs2_build_inode_pass1(c, ic); + if (ret) { + D1(printk(KERN_WARNING "Eep. jffs2_build_inode_pass1 for ino %d returned %d\n", ic->ino, ret)); + return ret; + } + } + D1(printk(KERN_DEBUG "Pass 1 complete\n")); + + /* Next, scan for inodes with nlink == 0 and remove them. If + they were directories, then decrement the nlink of their + children too, and repeat the scan. As that's going to be + a fairly uncommon occurrence, it's not so evil to do it this + way. Recursion bad. */ + do { + D1(printk(KERN_DEBUG "Pass 2 (re)starting\n")); + ret = 0; + for_each_inode(i, c, ic) { + D1(printk(KERN_DEBUG "Pass 2: ino #%u, nlink %d, ic %p, nodes %p\n", ic->ino, ic->nlink, ic, ic->nodes)); + if (ic->nlink) + continue; + + ret = jffs2_build_remove_unlinked_inode(c, ic); + if (ret) + break; + /* -EAGAIN means the inode's nlink was zero, so we deleted it, + and furthermore that it had children and their nlink has now + gone to zero too. So we have to restart the scan. */ + } + } while(ret == -EAGAIN); + + D1(printk(KERN_DEBUG "Pass 2 complete\n")); + + /* Finally, we can scan again and free the dirent nodes and scan_info structs */ + for_each_inode(i, c, ic) { + struct jffs2_scan_info *scan = ic->scan; + struct jffs2_full_dirent *fd; + D1(printk(KERN_DEBUG "Pass 3: ino #%u, ic %p, nodes %p\n", ic->ino, ic, ic->nodes)); + if (!scan) { + if (ic->nlink) { + D1(printk(KERN_WARNING "Why no scan struct for ino #%u which has nlink %d?\n", ic->ino, ic->nlink)); + } + continue; + } + ic->scan = NULL; + while(scan->dents) { + fd = scan->dents; + scan->dents = fd->next; + jffs2_free_full_dirent(fd); + } + kfree(scan); + } + D1(printk(KERN_DEBUG "Pass 3 complete\n")); + + return ret; +} + +int jffs2_build_inode_pass1(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic) +{ + struct jffs2_tmp_dnode_info *tn; + struct jffs2_full_dirent *fd; + struct jffs2_node_frag *fraglist = NULL; + struct jffs2_tmp_dnode_info *metadata = NULL; + + D1(printk(KERN_DEBUG "jffs2_build_inode building inode #%u\n", ic->ino)); + if (ic->ino > c->highest_ino) + c->highest_ino = ic->ino; + + if (!ic->scan->tmpnodes && ic->ino != 1) { + D1(printk(KERN_DEBUG "jffs2_build_inode: ino #%u has no data nodes!\n", ic->ino)); + } + /* Build the list to make sure any obsolete nodes are marked as such */ + while(ic->scan->tmpnodes) { + tn = ic->scan->tmpnodes; + ic->scan->tmpnodes = tn->next; + + if (metadata && tn->version > metadata->version) { + D1(printk(KERN_DEBUG "jffs2_build_inode_pass1 ignoring old metadata at 0x%08x\n", + metadata->fn->raw->flash_offset &~3)); + + jffs2_free_full_dnode(metadata->fn); + jffs2_free_tmp_dnode_info(metadata); + metadata = NULL; + } + + if (tn->fn->size) { + jffs2_add_full_dnode_to_fraglist (c, &fraglist, tn->fn); + jffs2_free_tmp_dnode_info(tn); + } else { + if (!metadata) { + metadata = tn; + } else { + D1(printk(KERN_DEBUG "jffs2_build_inode_pass1 ignoring new metadata at 0x%08x\n", + tn->fn->raw->flash_offset &~3)); + + jffs2_free_full_dnode(tn->fn); + jffs2_free_tmp_dnode_info(tn); + } + } + } + + /* OK. Now clear up */ + if (metadata) { + jffs2_free_full_dnode(metadata->fn); + jffs2_free_tmp_dnode_info(metadata); + } + metadata = NULL; + + while (fraglist) { + struct jffs2_node_frag *frag; + frag = fraglist; + fraglist = fraglist->next; + + if (frag->node && !(--frag->node->frags)) { + jffs2_free_full_dnode(frag->node); + } + jffs2_free_node_frag(frag); + } + + /* Now for each child, increase nlink */ + for(fd=ic->scan->dents; fd; fd = fd->next) { + struct jffs2_inode_cache *child_ic; + if (!fd->ino) + continue; + + child_ic = jffs2_get_ino_cache(c, fd->ino); + if (!child_ic) { + printk(KERN_NOTICE "Eep. Child \"%s\" (ino #%u) of dir ino #%u doesn't exist!\n", + fd->name, fd->ino, ic->ino); + continue; + } + + if (child_ic->nlink++ && fd->type == DT_DIR) { + printk(KERN_NOTICE "Child dir \"%s\" (ino #%u) of dir ino #%u appears to be a hard link\n", fd->name, fd->ino, ic->ino); + /* What do we do about it? */ + } + D1(printk(KERN_DEBUG "Increased nlink for child \"%s\" (ino #%u)\n", fd->name, fd->ino)); + /* Can't free them. We might need them in pass 2 */ + } + return 0; +} + +int jffs2_build_remove_unlinked_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic) +{ + struct jffs2_raw_node_ref *raw; + struct jffs2_full_dirent *fd; + int ret = 0; + + if(!ic->scan) { + D1(printk(KERN_DEBUG "ino #%u was already removed\n", ic->ino)); + return 0; + } + + D1(printk(KERN_DEBUG "JFFS2: Removing ino #%u with nlink == zero.\n", ic->ino)); + + for (raw = ic->nodes; raw != (void *)ic; raw = raw->next_in_ino) { + D1(printk(KERN_DEBUG "obsoleting node at 0x%08x\n", raw->flash_offset&~3)); + jffs2_mark_node_obsolete(c, raw); + } + + if (ic->scan->dents) { + printk(KERN_NOTICE "Inode #%u was a directory with children - removing those too...\n", ic->ino); + + while(ic->scan->dents) { + struct jffs2_inode_cache *child_ic; + + fd = ic->scan->dents; + ic->scan->dents = fd->next; + + D1(printk(KERN_DEBUG "Removing child \"%s\", ino #%u\n", + fd->name, fd->ino)); + + child_ic = jffs2_get_ino_cache(c, fd->ino); + if (!child_ic) { + printk(KERN_NOTICE "Cannot remove child \"%s\", ino #%u, because it doesn't exist\n", fd->name, fd->ino); + continue; + } + jffs2_free_full_dirent(fd); + child_ic->nlink--; + } + ret = -EAGAIN; + } + kfree(ic->scan); + ic->scan = NULL; + + /* + We don't delete the inocache from the hash list and free it yet. + The erase code will do that, when all the nodes are completely gone. + */ + + return ret; +} + +int jffs2_do_mount_fs(struct jffs2_sb_info *c) +{ + int i; + + c->free_size = c->flash_size; + c->nr_blocks = c->flash_size / c->sector_size; + c->blocks = kmalloc(sizeof(struct jffs2_eraseblock) * c->nr_blocks, GFP_KERNEL); + if (!c->blocks) + return -ENOMEM; + for (i=0; i<c->nr_blocks; i++) { + INIT_LIST_HEAD(&c->blocks[i].list); + c->blocks[i].offset = i * c->sector_size; + c->blocks[i].free_size = c->sector_size; + c->blocks[i].dirty_size = 0; + c->blocks[i].used_size = 0; + c->blocks[i].first_node = NULL; + c->blocks[i].last_node = NULL; + } + + spin_lock_init(&c->nodelist_lock); + init_MUTEX(&c->alloc_sem); + init_waitqueue_head(&c->erase_wait); + spin_lock_init(&c->erase_completion_lock); + spin_lock_init(&c->inocache_lock); + + INIT_LIST_HEAD(&c->clean_list); + INIT_LIST_HEAD(&c->dirty_list); + INIT_LIST_HEAD(&c->erasing_list); + INIT_LIST_HEAD(&c->erase_pending_list); + INIT_LIST_HEAD(&c->erase_complete_list); + INIT_LIST_HEAD(&c->free_list); + INIT_LIST_HEAD(&c->bad_list); + INIT_LIST_HEAD(&c->bad_used_list); + c->highest_ino = 1; + + if (jffs2_build_filesystem(c)) { + D1(printk(KERN_DEBUG "build_fs failed\n")); + jffs2_free_ino_caches(c); + jffs2_free_raw_node_refs(c); + kfree(c->blocks); + return -EIO; + } + return 0; +}
