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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/jffs2/nodelist.c | |
download | lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/jffs2/nodelist.c')
-rw-r--r-- | fs/jffs2/nodelist.c | 681 |
1 files changed, 681 insertions, 0 deletions
diff --git a/fs/jffs2/nodelist.c b/fs/jffs2/nodelist.c new file mode 100644 index 000000000000..cd6a8bd13e0b --- /dev/null +++ b/fs/jffs2/nodelist.c @@ -0,0 +1,681 @@ +/* + * JFFS2 -- Journalling Flash File System, Version 2. + * + * Copyright (C) 2001-2003 Red Hat, Inc. + * + * Created by David Woodhouse <dwmw2@infradead.org> + * + * For licensing information, see the file 'LICENCE' in this directory. + * + * $Id: nodelist.c,v 1.90 2004/12/08 17:59:20 dwmw2 Exp $ + * + */ + +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/fs.h> +#include <linux/mtd/mtd.h> +#include <linux/rbtree.h> +#include <linux/crc32.h> +#include <linux/slab.h> +#include <linux/pagemap.h> +#include "nodelist.h" + +void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new, struct jffs2_full_dirent **list) +{ + struct jffs2_full_dirent **prev = list; + D1(printk(KERN_DEBUG "jffs2_add_fd_to_list( %p, %p (->%p))\n", new, list, *list)); + + while ((*prev) && (*prev)->nhash <= new->nhash) { + if ((*prev)->nhash == new->nhash && !strcmp((*prev)->name, new->name)) { + /* Duplicate. Free one */ + if (new->version < (*prev)->version) { + D1(printk(KERN_DEBUG "Eep! Marking new dirent node obsolete\n")); + D1(printk(KERN_DEBUG "New dirent is \"%s\"->ino #%u. Old is \"%s\"->ino #%u\n", new->name, new->ino, (*prev)->name, (*prev)->ino)); + jffs2_mark_node_obsolete(c, new->raw); + jffs2_free_full_dirent(new); + } else { + D1(printk(KERN_DEBUG "Marking old dirent node (ino #%u) obsolete\n", (*prev)->ino)); + new->next = (*prev)->next; + jffs2_mark_node_obsolete(c, ((*prev)->raw)); + jffs2_free_full_dirent(*prev); + *prev = new; + } + goto out; + } + prev = &((*prev)->next); + } + new->next = *prev; + *prev = new; + + out: + D2(while(*list) { + printk(KERN_DEBUG "Dirent \"%s\" (hash 0x%08x, ino #%u\n", (*list)->name, (*list)->nhash, (*list)->ino); + list = &(*list)->next; + }); +} + +/* Put a new tmp_dnode_info into the list, keeping the list in + order of increasing version +*/ +static void jffs2_add_tn_to_list(struct jffs2_tmp_dnode_info *tn, struct jffs2_tmp_dnode_info **list) +{ + struct jffs2_tmp_dnode_info **prev = list; + + while ((*prev) && (*prev)->version < tn->version) { + prev = &((*prev)->next); + } + tn->next = (*prev); + *prev = tn; +} + +static void jffs2_free_tmp_dnode_info_list(struct jffs2_tmp_dnode_info *tn) +{ + struct jffs2_tmp_dnode_info *next; + + while (tn) { + next = tn; + tn = tn->next; + jffs2_free_full_dnode(next->fn); + jffs2_free_tmp_dnode_info(next); + } +} + +static void jffs2_free_full_dirent_list(struct jffs2_full_dirent *fd) +{ + struct jffs2_full_dirent *next; + + while (fd) { + next = fd->next; + jffs2_free_full_dirent(fd); + fd = next; + } +} + +/* Returns first valid node after 'ref'. May return 'ref' */ +static struct jffs2_raw_node_ref *jffs2_first_valid_node(struct jffs2_raw_node_ref *ref) +{ + while (ref && ref->next_in_ino) { + if (!ref_obsolete(ref)) + return ref; + D1(printk(KERN_DEBUG "node at 0x%08x is obsoleted. Ignoring.\n", ref_offset(ref))); + ref = ref->next_in_ino; + } + return NULL; +} + +/* Get tmp_dnode_info and full_dirent for all non-obsolete nodes associated + with this ino, returning the former in order of version */ + +int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_info *f, + struct jffs2_tmp_dnode_info **tnp, struct jffs2_full_dirent **fdp, + uint32_t *highest_version, uint32_t *latest_mctime, + uint32_t *mctime_ver) +{ + struct jffs2_raw_node_ref *ref, *valid_ref; + struct jffs2_tmp_dnode_info *tn, *ret_tn = NULL; + struct jffs2_full_dirent *fd, *ret_fd = NULL; + union jffs2_node_union node; + size_t retlen; + int err; + + *mctime_ver = 0; + + D1(printk(KERN_DEBUG "jffs2_get_inode_nodes(): ino #%u\n", f->inocache->ino)); + + spin_lock(&c->erase_completion_lock); + + valid_ref = jffs2_first_valid_node(f->inocache->nodes); + + if (!valid_ref) + printk(KERN_WARNING "Eep. No valid nodes for ino #%u\n", f->inocache->ino); + + while (valid_ref) { + /* We can hold a pointer to a non-obsolete node without the spinlock, + but _obsolete_ nodes may disappear at any time, if the block + they're in gets erased. So if we mark 'ref' obsolete while we're + not holding the lock, it can go away immediately. For that reason, + we find the next valid node first, before processing 'ref'. + */ + ref = valid_ref; + valid_ref = jffs2_first_valid_node(ref->next_in_ino); + spin_unlock(&c->erase_completion_lock); + + cond_resched(); + + /* FIXME: point() */ + err = jffs2_flash_read(c, (ref_offset(ref)), + min_t(uint32_t, ref_totlen(c, NULL, ref), sizeof(node)), + &retlen, (void *)&node); + if (err) { + printk(KERN_WARNING "error %d reading node at 0x%08x in get_inode_nodes()\n", err, ref_offset(ref)); + goto free_out; + } + + + /* Check we've managed to read at least the common node header */ + if (retlen < min_t(uint32_t, ref_totlen(c, NULL, ref), sizeof(node.u))) { + printk(KERN_WARNING "short read in get_inode_nodes()\n"); + err = -EIO; + goto free_out; + } + + switch (je16_to_cpu(node.u.nodetype)) { + case JFFS2_NODETYPE_DIRENT: + D1(printk(KERN_DEBUG "Node at %08x (%d) is a dirent node\n", ref_offset(ref), ref_flags(ref))); + if (ref_flags(ref) == REF_UNCHECKED) { + printk(KERN_WARNING "BUG: Dirent node at 0x%08x never got checked? How?\n", ref_offset(ref)); + BUG(); + } + if (retlen < sizeof(node.d)) { + printk(KERN_WARNING "short read in get_inode_nodes()\n"); + err = -EIO; + goto free_out; + } + /* sanity check */ + if (PAD((node.d.nsize + sizeof (node.d))) != PAD(je32_to_cpu (node.d.totlen))) { + printk(KERN_NOTICE "jffs2_get_inode_nodes(): Illegal nsize in node at 0x%08x: nsize 0x%02x, totlen %04x\n", + ref_offset(ref), node.d.nsize, je32_to_cpu(node.d.totlen)); + jffs2_mark_node_obsolete(c, ref); + spin_lock(&c->erase_completion_lock); + continue; + } + if (je32_to_cpu(node.d.version) > *highest_version) + *highest_version = je32_to_cpu(node.d.version); + if (ref_obsolete(ref)) { + /* Obsoleted. This cannot happen, surely? dwmw2 20020308 */ + printk(KERN_ERR "Dirent node at 0x%08x became obsolete while we weren't looking\n", + ref_offset(ref)); + BUG(); + } + + fd = jffs2_alloc_full_dirent(node.d.nsize+1); + if (!fd) { + err = -ENOMEM; + goto free_out; + } + fd->raw = ref; + fd->version = je32_to_cpu(node.d.version); + fd->ino = je32_to_cpu(node.d.ino); + fd->type = node.d.type; + + /* Pick out the mctime of the latest dirent */ + if(fd->version > *mctime_ver) { + *mctime_ver = fd->version; + *latest_mctime = je32_to_cpu(node.d.mctime); + } + + /* memcpy as much of the name as possible from the raw + dirent we've already read from the flash + */ + if (retlen > sizeof(struct jffs2_raw_dirent)) + memcpy(&fd->name[0], &node.d.name[0], min_t(uint32_t, node.d.nsize, (retlen-sizeof(struct jffs2_raw_dirent)))); + + /* Do we need to copy any more of the name directly + from the flash? + */ + if (node.d.nsize + sizeof(struct jffs2_raw_dirent) > retlen) { + /* FIXME: point() */ + int already = retlen - sizeof(struct jffs2_raw_dirent); + + err = jffs2_flash_read(c, (ref_offset(ref)) + retlen, + node.d.nsize - already, &retlen, &fd->name[already]); + if (!err && retlen != node.d.nsize - already) + err = -EIO; + + if (err) { + printk(KERN_WARNING "Read remainder of name in jffs2_get_inode_nodes(): error %d\n", err); + jffs2_free_full_dirent(fd); + goto free_out; + } + } + fd->nhash = full_name_hash(fd->name, node.d.nsize); + fd->next = NULL; + fd->name[node.d.nsize] = '\0'; + /* Wheee. We now have a complete jffs2_full_dirent structure, with + the name in it and everything. Link it into the list + */ + D1(printk(KERN_DEBUG "Adding fd \"%s\", ino #%u\n", fd->name, fd->ino)); + jffs2_add_fd_to_list(c, fd, &ret_fd); + break; + + case JFFS2_NODETYPE_INODE: + D1(printk(KERN_DEBUG "Node at %08x (%d) is a data node\n", ref_offset(ref), ref_flags(ref))); + if (retlen < sizeof(node.i)) { + printk(KERN_WARNING "read too short for dnode\n"); + err = -EIO; + goto free_out; + } + if (je32_to_cpu(node.i.version) > *highest_version) + *highest_version = je32_to_cpu(node.i.version); + D1(printk(KERN_DEBUG "version %d, highest_version now %d\n", je32_to_cpu(node.i.version), *highest_version)); + + if (ref_obsolete(ref)) { + /* Obsoleted. This cannot happen, surely? dwmw2 20020308 */ + printk(KERN_ERR "Inode node at 0x%08x became obsolete while we weren't looking\n", + ref_offset(ref)); + BUG(); + } + + /* If we've never checked the CRCs on this node, check them now. */ + if (ref_flags(ref) == REF_UNCHECKED) { + uint32_t crc, len; + struct jffs2_eraseblock *jeb; + + crc = crc32(0, &node, sizeof(node.i)-8); + if (crc != je32_to_cpu(node.i.node_crc)) { + printk(KERN_NOTICE "jffs2_get_inode_nodes(): CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", + ref_offset(ref), je32_to_cpu(node.i.node_crc), crc); + jffs2_mark_node_obsolete(c, ref); + spin_lock(&c->erase_completion_lock); + continue; + } + + /* sanity checks */ + if ( je32_to_cpu(node.i.offset) > je32_to_cpu(node.i.isize) || + PAD(je32_to_cpu(node.i.csize) + sizeof (node.i)) != PAD(je32_to_cpu(node.i.totlen))) { + printk(KERN_NOTICE "jffs2_get_inode_nodes(): Inode corrupted at 0x%08x, totlen %d, #ino %d, version %d, isize %d, csize %d, dsize %d \n", + ref_offset(ref), je32_to_cpu(node.i.totlen), je32_to_cpu(node.i.ino), + je32_to_cpu(node.i.version), je32_to_cpu(node.i.isize), + je32_to_cpu(node.i.csize), je32_to_cpu(node.i.dsize)); + jffs2_mark_node_obsolete(c, ref); + spin_lock(&c->erase_completion_lock); + continue; + } + + if (node.i.compr != JFFS2_COMPR_ZERO && je32_to_cpu(node.i.csize)) { + unsigned char *buf=NULL; + uint32_t pointed = 0; +#ifndef __ECOS + if (c->mtd->point) { + err = c->mtd->point (c->mtd, ref_offset(ref) + sizeof(node.i), je32_to_cpu(node.i.csize), + &retlen, &buf); + if (!err && retlen < je32_to_cpu(node.i.csize)) { + D1(printk(KERN_DEBUG "MTD point returned len too short: 0x%zx\n", retlen)); + c->mtd->unpoint(c->mtd, buf, ref_offset(ref) + sizeof(node.i), je32_to_cpu(node.i.csize)); + } else if (err){ + D1(printk(KERN_DEBUG "MTD point failed %d\n", err)); + } else + pointed = 1; /* succefully pointed to device */ + } +#endif + if(!pointed){ + buf = kmalloc(je32_to_cpu(node.i.csize), GFP_KERNEL); + if (!buf) + return -ENOMEM; + + err = jffs2_flash_read(c, ref_offset(ref) + sizeof(node.i), je32_to_cpu(node.i.csize), + &retlen, buf); + if (!err && retlen != je32_to_cpu(node.i.csize)) + err = -EIO; + if (err) { + kfree(buf); + return err; + } + } + crc = crc32(0, buf, je32_to_cpu(node.i.csize)); + if(!pointed) + kfree(buf); +#ifndef __ECOS + else + c->mtd->unpoint(c->mtd, buf, ref_offset(ref) + sizeof(node.i), je32_to_cpu(node.i.csize)); +#endif + + if (crc != je32_to_cpu(node.i.data_crc)) { + printk(KERN_NOTICE "jffs2_get_inode_nodes(): Data CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", + ref_offset(ref), je32_to_cpu(node.i.data_crc), crc); + jffs2_mark_node_obsolete(c, ref); + spin_lock(&c->erase_completion_lock); + continue; + } + + } + + /* Mark the node as having been checked and fix the accounting accordingly */ + spin_lock(&c->erase_completion_lock); + jeb = &c->blocks[ref->flash_offset / c->sector_size]; + len = ref_totlen(c, jeb, ref); + + jeb->used_size += len; + jeb->unchecked_size -= len; + c->used_size += len; + c->unchecked_size -= len; + + /* If node covers at least a whole page, or if it starts at the + beginning of a page and runs to the end of the file, or if + it's a hole node, mark it REF_PRISTINE, else REF_NORMAL. + + If it's actually overlapped, it'll get made NORMAL (or OBSOLETE) + when the overlapping node(s) get added to the tree anyway. + */ + if ((je32_to_cpu(node.i.dsize) >= PAGE_CACHE_SIZE) || + ( ((je32_to_cpu(node.i.offset)&(PAGE_CACHE_SIZE-1))==0) && + (je32_to_cpu(node.i.dsize)+je32_to_cpu(node.i.offset) == je32_to_cpu(node.i.isize)))) { + D1(printk(KERN_DEBUG "Marking node at 0x%08x REF_PRISTINE\n", ref_offset(ref))); + ref->flash_offset = ref_offset(ref) | REF_PRISTINE; + } else { + D1(printk(KERN_DEBUG "Marking node at 0x%08x REF_NORMAL\n", ref_offset(ref))); + ref->flash_offset = ref_offset(ref) | REF_NORMAL; + } + spin_unlock(&c->erase_completion_lock); + } + + tn = jffs2_alloc_tmp_dnode_info(); + if (!tn) { + D1(printk(KERN_DEBUG "alloc tn failed\n")); + err = -ENOMEM; + goto free_out; + } + + tn->fn = jffs2_alloc_full_dnode(); + if (!tn->fn) { + D1(printk(KERN_DEBUG "alloc fn failed\n")); + err = -ENOMEM; + jffs2_free_tmp_dnode_info(tn); + goto free_out; + } + tn->version = je32_to_cpu(node.i.version); + tn->fn->ofs = je32_to_cpu(node.i.offset); + /* There was a bug where we wrote hole nodes out with + csize/dsize swapped. Deal with it */ + if (node.i.compr == JFFS2_COMPR_ZERO && !je32_to_cpu(node.i.dsize) && je32_to_cpu(node.i.csize)) + tn->fn->size = je32_to_cpu(node.i.csize); + else // normal case... + tn->fn->size = je32_to_cpu(node.i.dsize); + tn->fn->raw = ref; + D1(printk(KERN_DEBUG "dnode @%08x: ver %u, offset %04x, dsize %04x\n", + ref_offset(ref), je32_to_cpu(node.i.version), + je32_to_cpu(node.i.offset), je32_to_cpu(node.i.dsize))); + jffs2_add_tn_to_list(tn, &ret_tn); + break; + + default: + if (ref_flags(ref) == REF_UNCHECKED) { + struct jffs2_eraseblock *jeb; + uint32_t len; + + printk(KERN_ERR "Eep. Unknown node type %04x at %08x was marked REF_UNCHECKED\n", + je16_to_cpu(node.u.nodetype), ref_offset(ref)); + + /* Mark the node as having been checked and fix the accounting accordingly */ + spin_lock(&c->erase_completion_lock); + jeb = &c->blocks[ref->flash_offset / c->sector_size]; + len = ref_totlen(c, jeb, ref); + + jeb->used_size += len; + jeb->unchecked_size -= len; + c->used_size += len; + c->unchecked_size -= len; + + mark_ref_normal(ref); + spin_unlock(&c->erase_completion_lock); + } + node.u.nodetype = cpu_to_je16(JFFS2_NODE_ACCURATE | je16_to_cpu(node.u.nodetype)); + if (crc32(0, &node, sizeof(struct jffs2_unknown_node)-4) != je32_to_cpu(node.u.hdr_crc)) { + /* Hmmm. This should have been caught at scan time. */ + printk(KERN_ERR "Node header CRC failed at %08x. But it must have been OK earlier.\n", + ref_offset(ref)); + printk(KERN_ERR "Node was: { %04x, %04x, %08x, %08x }\n", + je16_to_cpu(node.u.magic), je16_to_cpu(node.u.nodetype), je32_to_cpu(node.u.totlen), + je32_to_cpu(node.u.hdr_crc)); + jffs2_mark_node_obsolete(c, ref); + } else switch(je16_to_cpu(node.u.nodetype) & JFFS2_COMPAT_MASK) { + case JFFS2_FEATURE_INCOMPAT: + printk(KERN_NOTICE "Unknown INCOMPAT nodetype %04X at %08x\n", je16_to_cpu(node.u.nodetype), ref_offset(ref)); + /* EEP */ + BUG(); + break; + case JFFS2_FEATURE_ROCOMPAT: + printk(KERN_NOTICE "Unknown ROCOMPAT nodetype %04X at %08x\n", je16_to_cpu(node.u.nodetype), ref_offset(ref)); + if (!(c->flags & JFFS2_SB_FLAG_RO)) + BUG(); + break; + case JFFS2_FEATURE_RWCOMPAT_COPY: + printk(KERN_NOTICE "Unknown RWCOMPAT_COPY nodetype %04X at %08x\n", je16_to_cpu(node.u.nodetype), ref_offset(ref)); + break; + case JFFS2_FEATURE_RWCOMPAT_DELETE: + printk(KERN_NOTICE "Unknown RWCOMPAT_DELETE nodetype %04X at %08x\n", je16_to_cpu(node.u.nodetype), ref_offset(ref)); + jffs2_mark_node_obsolete(c, ref); + break; + } + + } + spin_lock(&c->erase_completion_lock); + + } + spin_unlock(&c->erase_completion_lock); + *tnp = ret_tn; + *fdp = ret_fd; + + return 0; + + free_out: + jffs2_free_tmp_dnode_info_list(ret_tn); + jffs2_free_full_dirent_list(ret_fd); + return err; +} + +void jffs2_set_inocache_state(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic, int state) +{ + spin_lock(&c->inocache_lock); + ic->state = state; + wake_up(&c->inocache_wq); + spin_unlock(&c->inocache_lock); +} + +/* During mount, this needs no locking. During normal operation, its + callers want to do other stuff while still holding the inocache_lock. + Rather than introducing special case get_ino_cache functions or + callbacks, we just let the caller do the locking itself. */ + +struct jffs2_inode_cache *jffs2_get_ino_cache(struct jffs2_sb_info *c, uint32_t ino) +{ + struct jffs2_inode_cache *ret; + + D2(printk(KERN_DEBUG "jffs2_get_ino_cache(): ino %u\n", ino)); + + ret = c->inocache_list[ino % INOCACHE_HASHSIZE]; + while (ret && ret->ino < ino) { + ret = ret->next; + } + + if (ret && ret->ino != ino) + ret = NULL; + + D2(printk(KERN_DEBUG "jffs2_get_ino_cache found %p for ino %u\n", ret, ino)); + return ret; +} + +void jffs2_add_ino_cache (struct jffs2_sb_info *c, struct jffs2_inode_cache *new) +{ + struct jffs2_inode_cache **prev; + D2(printk(KERN_DEBUG "jffs2_add_ino_cache: Add %p (ino #%u)\n", new, new->ino)); + spin_lock(&c->inocache_lock); + + prev = &c->inocache_list[new->ino % INOCACHE_HASHSIZE]; + + while ((*prev) && (*prev)->ino < new->ino) { + prev = &(*prev)->next; + } + new->next = *prev; + *prev = new; + + spin_unlock(&c->inocache_lock); +} + +void jffs2_del_ino_cache(struct jffs2_sb_info *c, struct jffs2_inode_cache *old) +{ + struct jffs2_inode_cache **prev; + D2(printk(KERN_DEBUG "jffs2_del_ino_cache: Del %p (ino #%u)\n", old, old->ino)); + spin_lock(&c->inocache_lock); + + prev = &c->inocache_list[old->ino % INOCACHE_HASHSIZE]; + + while ((*prev) && (*prev)->ino < old->ino) { + prev = &(*prev)->next; + } + if ((*prev) == old) { + *prev = old->next; + } + + spin_unlock(&c->inocache_lock); +} + +void jffs2_free_ino_caches(struct jffs2_sb_info *c) +{ + int i; + struct jffs2_inode_cache *this, *next; + + for (i=0; i<INOCACHE_HASHSIZE; i++) { + this = c->inocache_list[i]; + while (this) { + next = this->next; + D2(printk(KERN_DEBUG "jffs2_free_ino_caches: Freeing ino #%u at %p\n", this->ino, this)); + jffs2_free_inode_cache(this); + this = next; + } + c->inocache_list[i] = NULL; + } +} + +void jffs2_free_raw_node_refs(struct jffs2_sb_info *c) +{ + int i; + struct jffs2_raw_node_ref *this, *next; + + for (i=0; i<c->nr_blocks; i++) { + this = c->blocks[i].first_node; + while(this) { + next = this->next_phys; + jffs2_free_raw_node_ref(this); + this = next; + } + c->blocks[i].first_node = c->blocks[i].last_node = NULL; + } +} + +struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_t offset) +{ + /* The common case in lookup is that there will be a node + which precisely matches. So we go looking for that first */ + struct rb_node *next; + struct jffs2_node_frag *prev = NULL; + struct jffs2_node_frag *frag = NULL; + + D2(printk(KERN_DEBUG "jffs2_lookup_node_frag(%p, %d)\n", fragtree, offset)); + + next = fragtree->rb_node; + + while(next) { + frag = rb_entry(next, struct jffs2_node_frag, rb); + + D2(printk(KERN_DEBUG "Considering frag %d-%d (%p). left %p, right %p\n", + frag->ofs, frag->ofs+frag->size, frag, frag->rb.rb_left, frag->rb.rb_right)); + if (frag->ofs + frag->size <= offset) { + D2(printk(KERN_DEBUG "Going right from frag %d-%d, before the region we care about\n", + frag->ofs, frag->ofs+frag->size)); + /* Remember the closest smaller match on the way down */ + if (!prev || frag->ofs > prev->ofs) + prev = frag; + next = frag->rb.rb_right; + } else if (frag->ofs > offset) { + D2(printk(KERN_DEBUG "Going left from frag %d-%d, after the region we care about\n", + frag->ofs, frag->ofs+frag->size)); + next = frag->rb.rb_left; + } else { + D2(printk(KERN_DEBUG "Returning frag %d,%d, matched\n", + frag->ofs, frag->ofs+frag->size)); + return frag; + } + } + + /* Exact match not found. Go back up looking at each parent, + and return the closest smaller one */ + + if (prev) + D2(printk(KERN_DEBUG "No match. Returning frag %d,%d, closest previous\n", + prev->ofs, prev->ofs+prev->size)); + else + D2(printk(KERN_DEBUG "Returning NULL, empty fragtree\n")); + + return prev; +} + +/* Pass 'c' argument to indicate that nodes should be marked obsolete as + they're killed. */ +void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c) +{ + struct jffs2_node_frag *frag; + struct jffs2_node_frag *parent; + + if (!root->rb_node) + return; + + frag = (rb_entry(root->rb_node, struct jffs2_node_frag, rb)); + + while(frag) { + if (frag->rb.rb_left) { + D2(printk(KERN_DEBUG "Going left from frag (%p) %d-%d\n", + frag, frag->ofs, frag->ofs+frag->size)); + frag = frag_left(frag); + continue; + } + if (frag->rb.rb_right) { + D2(printk(KERN_DEBUG "Going right from frag (%p) %d-%d\n", + frag, frag->ofs, frag->ofs+frag->size)); + frag = frag_right(frag); + continue; + } + + D2(printk(KERN_DEBUG "jffs2_kill_fragtree: frag at 0x%x-0x%x: node %p, frags %d--\n", + frag->ofs, frag->ofs+frag->size, frag->node, + frag->node?frag->node->frags:0)); + + if (frag->node && !(--frag->node->frags)) { + /* Not a hole, and it's the final remaining frag + of this node. Free the node */ + if (c) + jffs2_mark_node_obsolete(c, frag->node->raw); + + jffs2_free_full_dnode(frag->node); + } + parent = frag_parent(frag); + if (parent) { + if (frag_left(parent) == frag) + parent->rb.rb_left = NULL; + else + parent->rb.rb_right = NULL; + } + + jffs2_free_node_frag(frag); + frag = parent; + + cond_resched(); + } +} + +void jffs2_fragtree_insert(struct jffs2_node_frag *newfrag, struct jffs2_node_frag *base) +{ + struct rb_node *parent = &base->rb; + struct rb_node **link = &parent; + + D2(printk(KERN_DEBUG "jffs2_fragtree_insert(%p; %d-%d, %p)\n", newfrag, + newfrag->ofs, newfrag->ofs+newfrag->size, base)); + + while (*link) { + parent = *link; + base = rb_entry(parent, struct jffs2_node_frag, rb); + + D2(printk(KERN_DEBUG "fragtree_insert considering frag at 0x%x\n", base->ofs)); + if (newfrag->ofs > base->ofs) + link = &base->rb.rb_right; + else if (newfrag->ofs < base->ofs) + link = &base->rb.rb_left; + else { + printk(KERN_CRIT "Duplicate frag at %08x (%p,%p)\n", newfrag->ofs, newfrag, base); + BUG(); + } + } + + rb_link_node(&newfrag->rb, &base->rb, link); +} |