diff options
Diffstat (limited to 'fs/jffs2/readinode.c')
| -rw-r--r-- | fs/jffs2/readinode.c | 851 |
1 files changed, 640 insertions, 211 deletions
diff --git a/fs/jffs2/readinode.c b/fs/jffs2/readinode.c index 717a48cf7df2..6aff38930b50 100644 --- a/fs/jffs2/readinode.c +++ b/fs/jffs2/readinode.c @@ -1,14 +1,12 @@ /* * JFFS2 -- Journalling Flash File System, Version 2. * - * Copyright (C) 2001-2003 Red Hat, Inc. + * Copyright © 2001-2007 Red Hat, Inc. * * Created by David Woodhouse <dwmw2@infradead.org> * * For licensing information, see the file 'LICENCE' in this directory. * - * $Id: readinode.c,v 1.143 2005/11/07 11:14:41 gleixner Exp $ - * */ #include <linux/kernel.h> @@ -22,30 +20,510 @@ #include "nodelist.h" /* - * Put a new tmp_dnode_info into the temporaty RB-tree, keeping the list in - * order of increasing version. + * Check the data CRC of the node. + * + * Returns: 0 if the data CRC is correct; + * 1 - if incorrect; + * error code if an error occured. */ -static void jffs2_add_tn_to_tree(struct jffs2_tmp_dnode_info *tn, struct rb_root *list) +static int check_node_data(struct jffs2_sb_info *c, struct jffs2_tmp_dnode_info *tn) { - struct rb_node **p = &list->rb_node; - struct rb_node * parent = NULL; - struct jffs2_tmp_dnode_info *this; - - while (*p) { - parent = *p; - this = rb_entry(parent, struct jffs2_tmp_dnode_info, rb); - - /* There may actually be a collision here, but it doesn't - actually matter. As long as the two nodes with the same - version are together, it's all fine. */ - if (tn->version > this->version) - p = &(*p)->rb_left; + struct jffs2_raw_node_ref *ref = tn->fn->raw; + int err = 0, pointed = 0; + struct jffs2_eraseblock *jeb; + unsigned char *buffer; + uint32_t crc, ofs, len; + size_t retlen; + + BUG_ON(tn->csize == 0); + + if (!jffs2_is_writebuffered(c)) + goto adj_acc; + + /* Calculate how many bytes were already checked */ + ofs = ref_offset(ref) + sizeof(struct jffs2_raw_inode); + len = ofs % c->wbuf_pagesize; + if (likely(len)) + len = c->wbuf_pagesize - len; + + if (len >= tn->csize) { + dbg_readinode("no need to check node at %#08x, data length %u, data starts at %#08x - it has already been checked.\n", + ref_offset(ref), tn->csize, ofs); + goto adj_acc; + } + + ofs += len; + len = tn->csize - len; + + dbg_readinode("check node at %#08x, data length %u, partial CRC %#08x, correct CRC %#08x, data starts at %#08x, start checking from %#08x - %u bytes.\n", + ref_offset(ref), tn->csize, tn->partial_crc, tn->data_crc, ofs - len, ofs, len); + +#ifndef __ECOS + /* TODO: instead, incapsulate point() stuff to jffs2_flash_read(), + * adding and jffs2_flash_read_end() interface. */ + if (c->mtd->point) { + err = c->mtd->point(c->mtd, ofs, len, &retlen, &buffer); + if (!err && retlen < tn->csize) { + JFFS2_WARNING("MTD point returned len too short: %zu instead of %u.\n", retlen, tn->csize); + c->mtd->unpoint(c->mtd, buffer, ofs, len); + } else if (err) + JFFS2_WARNING("MTD point failed: error code %d.\n", err); else - p = &(*p)->rb_right; + pointed = 1; /* succefully pointed to device */ + } +#endif + + if (!pointed) { + buffer = kmalloc(len, GFP_KERNEL); + if (unlikely(!buffer)) + return -ENOMEM; + + /* TODO: this is very frequent pattern, make it a separate + * routine */ + err = jffs2_flash_read(c, ofs, len, &retlen, buffer); + if (err) { + JFFS2_ERROR("can not read %d bytes from 0x%08x, error code: %d.\n", len, ofs, err); + goto free_out; + } + + if (retlen != len) { + JFFS2_ERROR("short read at %#08x: %zd instead of %d.\n", ofs, retlen, len); + err = -EIO; + goto free_out; + } + } + + /* Continue calculating CRC */ + crc = crc32(tn->partial_crc, buffer, len); + if(!pointed) + kfree(buffer); +#ifndef __ECOS + else + c->mtd->unpoint(c->mtd, buffer, ofs, len); +#endif + + if (crc != tn->data_crc) { + JFFS2_NOTICE("wrong data CRC in data node at 0x%08x: read %#08x, calculated %#08x.\n", + ofs, tn->data_crc, crc); + return 1; } - rb_link_node(&tn->rb, parent, p); - rb_insert_color(&tn->rb, list); +adj_acc: + jeb = &c->blocks[ref->flash_offset / c->sector_size]; + len = ref_totlen(c, jeb, ref); + /* If it should be REF_NORMAL, it'll get marked as such when + we build the fragtree, shortly. No need to worry about GC + moving it while it's marked REF_PRISTINE -- GC won't happen + till we've finished checking every inode anyway. */ + ref->flash_offset |= REF_PRISTINE; + /* + * Mark the node as having been checked and fix the + * accounting accordingly. + */ + spin_lock(&c->erase_completion_lock); + jeb->used_size += len; + jeb->unchecked_size -= len; + c->used_size += len; + c->unchecked_size -= len; + jffs2_dbg_acct_paranoia_check_nolock(c, jeb); + spin_unlock(&c->erase_completion_lock); + + return 0; + +free_out: + if(!pointed) + kfree(buffer); +#ifndef __ECOS + else + c->mtd->unpoint(c->mtd, buffer, ofs, len); +#endif + return err; +} + +/* + * Helper function for jffs2_add_older_frag_to_fragtree(). + * + * Checks the node if we are in the checking stage. + */ +static int check_tn_node(struct jffs2_sb_info *c, struct jffs2_tmp_dnode_info *tn) +{ + int ret; + + BUG_ON(ref_obsolete(tn->fn->raw)); + + /* We only check the data CRC of unchecked nodes */ + if (ref_flags(tn->fn->raw) != REF_UNCHECKED) + return 0; + + dbg_readinode("check node %#04x-%#04x, phys offs %#08x\n", + tn->fn->ofs, tn->fn->ofs + tn->fn->size, ref_offset(tn->fn->raw)); + + ret = check_node_data(c, tn); + if (unlikely(ret < 0)) { + JFFS2_ERROR("check_node_data() returned error: %d.\n", + ret); + } else if (unlikely(ret > 0)) { + dbg_readinode("CRC error, mark it obsolete.\n"); + jffs2_mark_node_obsolete(c, tn->fn->raw); + } + + return ret; +} + +static struct jffs2_tmp_dnode_info *jffs2_lookup_tn(struct rb_root *tn_root, uint32_t offset) +{ + struct rb_node *next; + struct jffs2_tmp_dnode_info *tn = NULL; + + dbg_readinode("root %p, offset %d\n", tn_root, offset); + + next = tn_root->rb_node; + + while (next) { + tn = rb_entry(next, struct jffs2_tmp_dnode_info, rb); + + if (tn->fn->ofs < offset) + next = tn->rb.rb_right; + else if (tn->fn->ofs >= offset) + next = tn->rb.rb_left; + else + break; + } + + return tn; +} + + +static void jffs2_kill_tn(struct jffs2_sb_info *c, struct jffs2_tmp_dnode_info *tn) +{ + jffs2_mark_node_obsolete(c, tn->fn->raw); + jffs2_free_full_dnode(tn->fn); + jffs2_free_tmp_dnode_info(tn); +} +/* + * This function is used when we read an inode. Data nodes arrive in + * arbitrary order -- they may be older or newer than the nodes which + * are already in the tree. Where overlaps occur, the older node can + * be discarded as long as the newer passes the CRC check. We don't + * bother to keep track of holes in this rbtree, and neither do we deal + * with frags -- we can have multiple entries starting at the same + * offset, and the one with the smallest length will come first in the + * ordering. + * + * Returns 0 if the node was inserted + * 1 if the node is obsolete (because we can't mark it so yet) + * < 0 an if error occurred + */ +static int jffs2_add_tn_to_tree(struct jffs2_sb_info *c, + struct jffs2_readinode_info *rii, + struct jffs2_tmp_dnode_info *tn) +{ + uint32_t fn_end = tn->fn->ofs + tn->fn->size; + struct jffs2_tmp_dnode_info *insert_point = NULL, *this; + + dbg_readinode("insert fragment %#04x-%#04x, ver %u\n", tn->fn->ofs, fn_end, tn->version); + + /* If a node has zero dsize, we only have to keep if it if it might be the + node with highest version -- i.e. the one which will end up as f->metadata. + Note that such nodes won't be REF_UNCHECKED since there are no data to + check anyway. */ + if (!tn->fn->size) { + if (rii->mdata_tn) { + /* We had a candidate mdata node already */ + dbg_readinode("kill old mdata with ver %d\n", rii->mdata_tn->version); + jffs2_kill_tn(c, rii->mdata_tn); + } + rii->mdata_tn = tn; + dbg_readinode("keep new mdata with ver %d\n", tn->version); + return 0; + } + + /* Find the earliest node which _may_ be relevant to this one */ + this = jffs2_lookup_tn(&rii->tn_root, tn->fn->ofs); + if (!this) { + /* First addition to empty tree. $DEITY how I love the easy cases */ + rb_link_node(&tn->rb, NULL, &rii->tn_root.rb_node); + rb_insert_color(&tn->rb, &rii->tn_root); + dbg_readinode("keep new frag\n"); + return 0; + } + + /* If we add a new node it'll be somewhere under here. */ + insert_point = this; + + /* If the node is coincident with another at a lower address, + back up until the other node is found. It may be relevant */ + while (tn->overlapped) + tn = tn_prev(tn); + + dbg_readinode("'this' found %#04x-%#04x (%s)\n", this->fn->ofs, this->fn->ofs + this->fn->size, this->fn ? "data" : "hole"); + + while (this) { + if (this->fn->ofs > fn_end) + break; + dbg_readinode("Ponder this ver %d, 0x%x-0x%x\n", + this->version, this->fn->ofs, this->fn->size); + + if (this->version == tn->version) { + /* Version number collision means REF_PRISTINE GC. Accept either of them + as long as the CRC is correct. Check the one we have already... */ + if (!check_tn_node(c, this)) { + /* The one we already had was OK. Keep it and throw away the new one */ + dbg_readinode("Like old node. Throw away new\n"); + jffs2_kill_tn(c, tn); + return 0; + } else { + /* Who cares if the new one is good; keep it for now anyway. */ + rb_replace_node(&this->rb, &tn->rb, &rii->tn_root); + /* Same overlapping from in front and behind */ + tn->overlapped = this->overlapped; + jffs2_kill_tn(c, this); + dbg_readinode("Like new node. Throw away old\n"); + return 0; + } + } + if (this->version < tn->version && + this->fn->ofs >= tn->fn->ofs && + this->fn->ofs + this->fn->size <= fn_end) { + /* New node entirely overlaps 'this' */ + if (check_tn_node(c, tn)) { + dbg_readinode("new node bad CRC\n"); + jffs2_kill_tn(c, tn); + return 0; + } + /* ... and is good. Kill 'this'... */ + rb_replace_node(&this->rb, &tn->rb, &rii->tn_root); + tn->overlapped = this->overlapped; + jffs2_kill_tn(c, this); + /* ... and any subsequent nodes which are also overlapped */ + this = tn_next(tn); + while (this && this->fn->ofs + this->fn->size < fn_end) { + struct jffs2_tmp_dnode_info *next = tn_next(this); + if (this->version < tn->version) { + tn_erase(this, &rii->tn_root); + dbg_readinode("Kill overlapped ver %d, 0x%x-0x%x\n", + this->version, this->fn->ofs, + this->fn->ofs+this->fn->size); + jffs2_kill_tn(c, this); + } + this = next; + } + dbg_readinode("Done inserting new\n"); + return 0; + } + if (this->version > tn->version && + this->fn->ofs <= tn->fn->ofs && + this->fn->ofs+this->fn->size >= fn_end) { + /* New node entirely overlapped by 'this' */ + if (!check_tn_node(c, this)) { + dbg_readinode("Good CRC on old node. Kill new\n"); + jffs2_kill_tn(c, tn); + return 0; + } + /* ... but 'this' was bad. Replace it... */ + rb_replace_node(&this->rb, &tn->rb, &rii->tn_root); + dbg_readinode("Bad CRC on old overlapping node. Kill it\n"); + jffs2_kill_tn(c, this); + return 0; + } + /* We want to be inserted under the last node which is + either at a lower offset _or_ has a smaller range */ + if (this->fn->ofs < tn->fn->ofs || + (this->fn->ofs == tn->fn->ofs && + this->fn->size <= tn->fn->size)) + insert_point = this; + + this = tn_next(this); + } + dbg_readinode("insert_point %p, ver %d, 0x%x-0x%x, ov %d\n", + insert_point, insert_point->version, insert_point->fn->ofs, + insert_point->fn->ofs+insert_point->fn->size, + insert_point->overlapped); + /* We neither completely obsoleted nor were completely + obsoleted by an earlier node. Insert under insert_point */ + { + struct rb_node *parent = &insert_point->rb; + struct rb_node **link = &parent; + + while (*link) { + parent = *link; + insert_point = rb_entry(parent, struct jffs2_tmp_dnode_info, rb); + if (tn->fn->ofs > insert_point->fn->ofs) + link = &insert_point->rb.rb_right; + else if (tn->fn->ofs < insert_point->fn->ofs || + tn->fn->size < insert_point->fn->size) + link = &insert_point->rb.rb_left; + else + link = &insert_point->rb.rb_right; + } + rb_link_node(&tn->rb, &insert_point->rb, link); + rb_insert_color(&tn->rb, &rii->tn_root); + } + /* If there's anything behind that overlaps us, note it */ + this = tn_prev(tn); + if (this) { + while (1) { + if (this->fn->ofs + this->fn->size > tn->fn->ofs) { + dbg_readinode("Node is overlapped by %p (v %d, 0x%x-0x%x)\n", + this, this->version, this->fn->ofs, + this->fn->ofs+this->fn->size); + tn->overlapped = 1; + break; + } + if (!this->overlapped) + break; + this = tn_prev(this); + } + } + + /* If the new node overlaps anything ahead, note it */ + this = tn_next(tn); + while (this && this->fn->ofs < fn_end) { + this->overlapped = 1; + dbg_readinode("Node ver %d, 0x%x-0x%x is overlapped\n", + this->version, this->fn->ofs, + this->fn->ofs+this->fn->size); + this = tn_next(this); + } + return 0; +} + +/* Trivial function to remove the last node in the tree. Which by definition + has no right-hand -- so can be removed just by making its only child (if + any) take its place under its parent. */ +static void eat_last(struct rb_root *root, struct rb_node *node) +{ + struct rb_node *parent = rb_parent(node); + struct rb_node **link; + + /* LAST! */ + BUG_ON(node->rb_right); + + if (!parent) + link = &root->rb_node; + else if (node == parent->rb_left) + link = &parent->rb_left; + else + link = &parent->rb_right; + + *link = node->rb_left; + /* Colour doesn't matter now. Only the parent pointer. */ + if (node->rb_left) + node->rb_left->rb_parent_color = node->rb_parent_color; +} + +/* We put this in reverse order, so we can just use eat_last */ +static void ver_insert(struct rb_root *ver_root, struct jffs2_tmp_dnode_info *tn) +{ + struct rb_node **link = &ver_root->rb_node; + struct rb_node *parent = NULL; + struct jffs2_tmp_dnode_info *this_tn; + + while (*link) { + parent = *link; + this_tn = rb_entry(parent, struct jffs2_tmp_dnode_info, rb); + + if (tn->version > this_tn->version) + link = &parent->rb_left; + else + link = &parent->rb_right; + } + dbg_readinode("Link new node at %p (root is %p)\n", link, ver_root); + rb_link_node(&tn->rb, parent, link); + rb_insert_color(&tn->rb, ver_root); +} + +/* Build final, normal fragtree from tn tree. It doesn't matter which order + we add nodes to the real fragtree, as long as they don't overlap. And + having thrown away the majority of overlapped nodes as we went, there + really shouldn't be many sets of nodes which do overlap. If we start at + the end, we can use the overlap markers -- we can just eat nodes which + aren't overlapped, and when we encounter nodes which _do_ overlap we + sort them all into a temporary tree in version order before replaying them. */ +static int jffs2_build_inode_fragtree(struct jffs2_sb_info *c, + struct jffs2_inode_info *f, + struct jffs2_readinode_info *rii) +{ + struct jffs2_tmp_dnode_info *pen, *last, *this; + struct rb_root ver_root = RB_ROOT; + uint32_t high_ver = 0; + + if (rii->mdata_tn) { + dbg_readinode("potential mdata is ver %d at %p\n", rii->mdata_tn->version, rii->mdata_tn); + high_ver = rii->mdata_tn->version; + rii->latest_ref = rii->mdata_tn->fn->raw; + } +#ifdef JFFS2_DBG_READINODE_MESSAGES + this = tn_last(&rii->tn_root); + while (this) { + dbg_readinode("tn %p ver %d range 0x%x-0x%x ov %d\n", this, this->version, this->fn->ofs, + this->fn->ofs+this->fn->size, this->overlapped); + this = tn_prev(this); + } +#endif + pen = tn_last(&rii->tn_root); + while ((last = pen)) { + pen = tn_prev(last); + + eat_last(&rii->tn_root, &last->rb); + ver_insert(&ver_root, last); + + if (unlikely(last->overlapped)) + continue; + + /* Now we have a bunch of nodes in reverse version + order, in the tree at ver_root. Most of the time, + there'll actually be only one node in the 'tree', + in fact. */ + this = tn_last(&ver_root); + + while (this) { + struct jffs2_tmp_dnode_info *vers_next; + int ret; + vers_next = tn_prev(this); + eat_last(&ver_root, &this->rb); + if (check_tn_node(c, this)) { + dbg_readinode("node ver %x, 0x%x-0x%x failed CRC\n", + this->version, this->fn->ofs, + this->fn->ofs+this->fn->size); + jffs2_kill_tn(c, this); + } else { + if (this->version > high_ver) { + /* Note that this is different from the other + highest_version, because this one is only + counting _valid_ nodes which could give the + latest inode metadata */ + high_ver = this->version; + rii->latest_ref = this->fn->raw; + } + dbg_readinode("Add %p (v %x, 0x%x-0x%x, ov %d) to fragtree\n", + this, this->version, this->fn->ofs, + this->fn->ofs+this->fn->size, this->overlapped); + + ret = jffs2_add_full_dnode_to_inode(c, f, this->fn); + if (ret) { + /* Free the nodes in vers_root; let the caller + deal with the rest */ + JFFS2_ERROR("Add node to tree failed %d\n", ret); + while (1) { + vers_next = tn_prev(this); + if (check_tn_node(c, this)) + jffs2_mark_node_obsolete(c, this->fn->raw); + jffs2_free_full_dnode(this->fn); + jffs2_free_tmp_dnode_info(this); + this = vers_next; + if (!this) + break; + eat_last(&ver_root, &vers_next->rb); + } + return ret; + } + jffs2_free_tmp_dnode_info(this); + } + this = vers_next; + } + } + return 0; } static void jffs2_free_tmp_dnode_info_list(struct rb_root *list) @@ -112,8 +590,8 @@ static struct jffs2_raw_node_ref *jffs2_first_valid_node(struct jffs2_raw_node_r * negative error code on failure. */ static inline int read_direntry(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, - struct jffs2_raw_dirent *rd, size_t read, struct jffs2_full_dirent **fdp, - uint32_t *latest_mctime, uint32_t *mctime_ver) + struct jffs2_raw_dirent *rd, size_t read, + struct jffs2_readinode_info *rii) { struct jffs2_full_dirent *fd; uint32_t crc; @@ -125,7 +603,8 @@ static inline int read_direntry(struct jffs2_sb_info *c, struct jffs2_raw_node_r if (unlikely(crc != je32_to_cpu(rd->node_crc))) { JFFS2_NOTICE("header CRC failed on dirent node at %#08x: read %#08x, calculated %#08x\n", ref_offset(ref), je32_to_cpu(rd->node_crc), crc); - return 1; + jffs2_mark_node_obsolete(c, ref); + return 0; } /* If we've never checked the CRCs on this node, check them now */ @@ -137,7 +616,8 @@ static inline int read_direntry(struct jffs2_sb_info *c, struct jffs2_raw_node_r if (unlikely(PAD((rd->nsize + sizeof(*rd))) != PAD(je32_to_cpu(rd->totlen)))) { JFFS2_ERROR("illegal nsize in node at %#08x: nsize %#02x, totlen %#04x\n", ref_offset(ref), rd->nsize, je32_to_cpu(rd->totlen)); - return 1; + jffs2_mark_node_obsolete(c, ref); + return 0; } jeb = &c->blocks[ref->flash_offset / c->sector_size]; @@ -161,10 +641,13 @@ static inline int read_direntry(struct jffs2_sb_info *c, struct jffs2_raw_node_r fd->ino = je32_to_cpu(rd->ino); fd->type = rd->type; + if (fd->version > rii->highest_version) + rii->highest_version = fd->version; + /* Pick out the mctime of the latest dirent */ - if(fd->version > *mctime_ver && je32_to_cpu(rd->mctime)) { - *mctime_ver = fd->version; - *latest_mctime = je32_to_cpu(rd->mctime); + if(fd->version > rii->mctime_ver && je32_to_cpu(rd->mctime)) { + rii->mctime_ver = fd->version; + rii->latest_mctime = je32_to_cpu(rd->mctime); } /* @@ -201,7 +684,7 @@ static inline int read_direntry(struct jffs2_sb_info *c, struct jffs2_raw_node_r * Wheee. We now have a complete jffs2_full_dirent structure, with * the name in it and everything. Link it into the list */ - jffs2_add_fd_to_list(c, fd, fdp); + jffs2_add_fd_to_list(c, fd, &rii->fds); return 0; } @@ -210,13 +693,13 @@ static inline int read_direntry(struct jffs2_sb_info *c, struct jffs2_raw_node_r * Helper function for jffs2_get_inode_nodes(). * It is called every time an inode node is found. * - * Returns: 0 on succes; + * Returns: 0 on success; * 1 if the node should be marked obsolete; * negative error code on failure. */ static inline int read_dnode(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, - struct jffs2_raw_inode *rd, struct rb_root *tnp, int rdlen, - uint32_t *latest_mctime, uint32_t *mctime_ver) + struct jffs2_raw_inode *rd, int rdlen, + struct jffs2_readinode_info *rii) { struct jffs2_tmp_dnode_info *tn; uint32_t len, csize; @@ -230,7 +713,8 @@ static inline int read_dnode(struct jffs2_sb_info *c, struct jffs2_raw_node_ref if (unlikely(crc != je32_to_cpu(rd->node_crc))) { JFFS2_NOTICE("node CRC failed on dnode at %#08x: read %#08x, calculated %#08x\n", ref_offset(ref), je32_to_cpu(rd->node_crc), crc); - return 1; + jffs2_mark_node_obsolete(c, ref); + return 0; } tn = jffs2_alloc_tmp_dnode_info(); @@ -342,6 +826,10 @@ static inline int read_dnode(struct jffs2_sb_info *c, struct jffs2_raw_node_ref tn->data_crc = je32_to_cpu(rd->data_crc); tn->csize = csize; tn->fn->raw = ref; + tn->overlapped = 0; + + if (tn->version > rii->highest_version) + rii->highest_version = tn->version; /* There was a bug where we wrote hole nodes out with csize/dsize swapped. Deal with it */ @@ -353,13 +841,25 @@ static inline int read_dnode(struct jffs2_sb_info *c, struct jffs2_raw_node_ref dbg_readinode("dnode @%08x: ver %u, offset %#04x, dsize %#04x, csize %#04x\n", ref_offset(ref), je32_to_cpu(rd->version), je32_to_cpu(rd->offset), je32_to_cpu(rd->dsize), csize); - jffs2_add_tn_to_tree(tn, tnp); + ret = jffs2_add_tn_to_tree(c, rii, tn); + if (ret) { + jffs2_free_full_dnode(tn->fn); + free_out: + jffs2_free_tmp_dnode_info(tn); + return ret; + } +#ifdef JFFS2_DBG_READINODE_MESSAGES + dbg_readinode("After adding ver %d:\n", tn->version); + tn = tn_first(&rii->tn_root); + while (tn) { + dbg_readinode("%p: v %d r 0x%x-0x%x ov %d\n", + tn, tn->version, tn->fn->ofs, + tn->fn->ofs+tn->fn->size, tn->overlapped); + tn = tn_next(tn); + } +#endif return 0; - -free_out: - jffs2_free_tmp_dnode_info(tn); - return ret; } /* @@ -379,7 +879,8 @@ static inline int read_unknown(struct jffs2_sb_info *c, struct jffs2_raw_node_re JFFS2_ERROR("Node is {%04x,%04x,%08x,%08x}. Please report this error.\n", je16_to_cpu(un->magic), je16_to_cpu(un->nodetype), je32_to_cpu(un->totlen), je32_to_cpu(un->hdr_crc)); - return 1; + jffs2_mark_node_obsolete(c, ref); + return 0; } un->nodetype = cpu_to_je16(JFFS2_NODE_ACCURATE | je16_to_cpu(un->nodetype)); @@ -407,7 +908,8 @@ static inline int read_unknown(struct jffs2_sb_info *c, struct jffs2_raw_node_re case JFFS2_FEATURE_RWCOMPAT_DELETE: JFFS2_NOTICE("unknown RWCOMPAT_DELETE nodetype %#04X at %#08x\n", je16_to_cpu(un->nodetype), ref_offset(ref)); - return 1; + jffs2_mark_node_obsolete(c, ref); + return 0; } return 0; @@ -421,92 +923,62 @@ static inline int read_unknown(struct jffs2_sb_info *c, struct jffs2_raw_node_re * negative error code on failure. */ static int read_more(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, - int right_size, int *rdlen, unsigned char *buf, unsigned char *bufstart) + int needed_len, int *rdlen, unsigned char *buf) { - int right_len, err, len; + int err, to_read = needed_len - *rdlen; size_t retlen; uint32_t offs; if (jffs2_is_writebuffered(c)) { - right_len = c->wbuf_pagesize - (bufstart - buf); - if (right_size + (int)(bufstart - buf) > c->wbuf_pagesize) - right_len += c->wbuf_pagesize; - } else - right_len = right_size; + int rem = to_read % c->wbuf_pagesize; - if (*rdlen == right_len) - return 0; + if (rem) + to_read += c->wbuf_pagesize - rem; + } /* We need to read more data */ offs = ref_offset(ref) + *rdlen; - if (jffs2_is_writebuffered(c)) { - bufstart = buf + c->wbuf_pagesize; - len = c->wbuf_pagesize; - } else { - bufstart = buf + *rdlen; - len = right_size - *rdlen; - } - dbg_readinode("read more %d bytes\n", len); + dbg_readinode("read more %d bytes\n", to_read); - err = jffs2_flash_read(c, offs, len, &retlen, bufstart); + err = jffs2_flash_read(c, offs, to_read, &retlen, buf + *rdlen); if (err) { JFFS2_ERROR("can not read %d bytes from 0x%08x, " - "error code: %d.\n", len, offs, err); + "error code: %d.\n", to_read, offs, err); return err; } - if (retlen < len) { + if (retlen < to_read) { JFFS2_ERROR("short read at %#08x: %zu instead of %d.\n", - offs, retlen, len); + offs, retlen, to_read); return -EIO; } - *rdlen = right_len; - + *rdlen += to_read; return 0; } /* Get tmp_dnode_info and full_dirent for all non-obsolete nodes associated - with this ino, returning the former in order of version */ + with this ino. Perform a preliminary ordering on data nodes, throwing away + those which are completely obsoleted by newer ones. The naïve approach we + use to take of just returning them _all_ in version order will cause us to + run out of memory in certain degenerate cases. */ static int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_info *f, - struct rb_root *tnp, struct jffs2_full_dirent **fdp, - uint32_t *highest_version, uint32_t *latest_mctime, - uint32_t *mctime_ver) + struct jffs2_readinode_info *rii) { struct jffs2_raw_node_ref *ref, *valid_ref; - struct rb_root ret_tn = RB_ROOT; - struct jffs2_full_dirent *ret_fd = NULL; unsigned char *buf = NULL; union jffs2_node_union *node; size_t retlen; int len, err; - *mctime_ver = 0; + rii->mctime_ver = 0; dbg_readinode("ino #%u\n", f->inocache->ino); - if (jffs2_is_writebuffered(c)) { - /* - * If we have the write buffer, we assume the minimal I/O unit - * is c->wbuf_pagesize. We implement some optimizations which in - * this case and we need a temporary buffer of size = - * 2*c->wbuf_pagesize bytes (see comments in read_dnode()). - * Basically, we want to read not only the node header, but the - * whole wbuf (NAND page in case of NAND) or 2, if the node - * header overlaps the border between the 2 wbufs. - */ - len = 2*c->wbuf_pagesize; - } else { - /* - * When there is no write buffer, the size of the temporary - * buffer is the size of the larges node header. - */ - len = sizeof(union jffs2_node_union); - } - /* FIXME: in case of NOR and available ->point() this * needs to be fixed. */ + len = sizeof(union jffs2_node_union) + c->wbuf_pagesize; buf = kmalloc(len, GFP_KERNEL); if (!buf) return -ENOMEM; @@ -516,8 +988,6 @@ static int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_inf if (!valid_ref && f->inocache->ino != 1) JFFS2_WARNING("Eep. No valid nodes for ino #%u.\n", f->inocache->ino); while (valid_ref) { - unsigned char *bufstart; - /* 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 @@ -533,32 +1003,31 @@ static int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_inf /* * At this point we don't know the type of the node we're going * to read, so we do not know the size of its header. In order - * to minimize the amount of flash IO we assume the node has - * size = JFFS2_MIN_NODE_HEADER. + * to minimize the amount of flash IO we assume the header is + * of size = JFFS2_MIN_NODE_HEADER. */ + len = JFFS2_MIN_NODE_HEADER; if (jffs2_is_writebuffered(c)) { + int end, rem; + /* - * We treat 'buf' as 2 adjacent wbufs. We want to - * adjust bufstart such as it points to the - * beginning of the node within this wbuf. + * We are about to read JFFS2_MIN_NODE_HEADER bytes, + * but this flash has some minimal I/O unit. It is + * possible that we'll need to read more soon, so read + * up to the next min. I/O unit, in order not to + * re-read the same min. I/O unit twice. */ - bufstart = buf + (ref_offset(ref) % c->wbuf_pagesize); - /* We will read either one wbuf or 2 wbufs. */ - len = c->wbuf_pagesize - (bufstart - buf); - if (JFFS2_MIN_NODE_HEADER + (int)(bufstart - buf) > c->wbuf_pagesize) { - /* The header spans the border of the first wbuf */ - len += c->wbuf_pagesize; - } - } else { - bufstart = buf; - len = JFFS2_MIN_NODE_HEADER; + end = ref_offset(ref) + len; + rem = end % c->wbuf_pagesize; + if (rem) + end += c->wbuf_pagesize - rem; + len = end - ref_offset(ref); } dbg_readinode("read %d bytes at %#08x(%d).\n", len, ref_offset(ref), ref_flags(ref)); /* FIXME: point() */ - err = jffs2_flash_read(c, ref_offset(ref), len, - &retlen, bufstart); + err = jffs2_flash_read(c, ref_offset(ref), len, &retlen, buf); if (err) { JFFS2_ERROR("can not read %d bytes from 0x%08x, " "error code: %d.\n", len, ref_offset(ref), err); goto free_out; @@ -570,7 +1039,7 @@ static int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_inf goto free_out; } - node = (union jffs2_node_union *)bufstart; + node = (union jffs2_node_union *)buf; /* No need to mask in the valid bit; it shouldn't be invalid */ if (je32_to_cpu(node->u.hdr_crc) != crc32(0, node, sizeof(node->u)-4)) { @@ -583,10 +1052,10 @@ static int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_inf jffs2_mark_node_obsolete(c, ref); goto cont; } - /* Due to poor choice of crc32 seed, an all-zero node will have a correct CRC */ - if (!je32_to_cpu(node->u.hdr_crc) && !je16_to_cpu(node->u.nodetype) && - !je16_to_cpu(node->u.magic) && !je32_to_cpu(node->u.totlen)) { - JFFS2_NOTICE("All zero node header at %#08x.\n", ref_offset(ref)); + if (je16_to_cpu(node->u.magic) != JFFS2_MAGIC_BITMASK) { + /* Not a JFFS2 node, whinge and move on */ + JFFS2_NOTICE("Wrong magic bitmask 0x%04x in node header at %#08x.\n", + je16_to_cpu(node->u.magic), ref_offset(ref)); jffs2_mark_node_obsolete(c, ref); goto cont; } @@ -596,46 +1065,34 @@ static int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_inf case JFFS2_NODETYPE_DIRENT: if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_raw_dirent)) { - err = read_more(c, ref, sizeof(struct jffs2_raw_dirent), &len, buf, bufstart); + err = read_more(c, ref, sizeof(struct jffs2_raw_dirent), &len, buf); if (unlikely(err)) goto free_out; } - err = read_direntry(c, ref, &node->d, retlen, &ret_fd, latest_mctime, mctime_ver); - if (err == 1) { - jffs2_mark_node_obsolete(c, ref); - break; - } else if (unlikely(err)) + err = read_direntry(c, ref, &node->d, retlen, rii); + if (unlikely(err)) goto free_out; - if (je32_to_cpu(node->d.version) > *highest_version) - *highest_version = je32_to_cpu(node->d.version); - break; case JFFS2_NODETYPE_INODE: if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_raw_inode)) { - err = read_more(c, ref, sizeof(struct jffs2_raw_inode), &len, buf, bufstart); + err = read_more(c, ref, sizeof(struct jffs2_raw_inode), &len, buf); if (unlikely(err)) goto free_out; } - err = read_dnode(c, ref, &node->i, &ret_tn, len, latest_mctime, mctime_ver); - if (err == 1) { - jffs2_mark_node_obsolete(c, ref); - break; - } else if (unlikely(err)) + err = read_dnode(c, ref, &node->i, len, rii); + if (unlikely(err)) goto free_out; - if (je32_to_cpu(node->i.version) > *highest_version) - *highest_version = je32_to_cpu(node->i.version); - break; default: if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_unknown_node)) { - err = read_more(c, ref, sizeof(struct jffs2_unknown_node), &len, buf, bufstart); + err = read_more(c, ref, sizeof(struct jffs2_unknown_node), &len, buf); if (unlikely(err)) goto free_out; } @@ -653,17 +1110,19 @@ static int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_inf } spin_unlock(&c->erase_completion_lock); - *tnp = ret_tn; - *fdp = ret_fd; kfree(buf); + f->highest_version = rii->highest_version; + dbg_readinode("nodes of inode #%u were read, the highest version is %u, latest_mctime %u, mctime_ver %u.\n", - f->inocache->ino, *highest_version, *latest_mctime, *mctime_ver); + f->inocache->ino, rii->highest_version, rii->latest_mctime, + rii->mctime_ver); return 0; free_out: - jffs2_free_tmp_dnode_info_list(&ret_tn); - jffs2_free_full_dirent_list(ret_fd); + jffs2_free_tmp_dnode_info_list(&rii->tn_root); + jffs2_free_full_dirent_list(rii->fds); + rii->fds = NULL; kfree(buf); return err; } @@ -672,20 +1131,17 @@ static int jffs2_do_read_inode_internal(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_raw_inode *latest_node) { - struct jffs2_tmp_dnode_info *tn; - struct rb_root tn_list; - struct rb_node *rb, *repl_rb; - struct jffs2_full_dirent *fd_list; - struct jffs2_full_dnode *fn, *first_fn = NULL; - uint32_t crc; - uint32_t latest_mctime, mctime_ver; + struct jffs2_readinode_info rii; + uint32_t crc, new_size; size_t retlen; int ret; dbg_readinode("ino #%u nlink is %d\n", f->inocache->ino, f->inocache->nlink); + memset(&rii, 0, sizeof(rii)); + /* Grab all nodes relevant to this ino */ - ret = jffs2_get_inode_nodes(c, f, &tn_list, &fd_list, &f->highest_version, &latest_mctime, &mctime_ver); + ret = jffs2_get_inode_nodes(c, f, &rii); if (ret) { JFFS2_ERROR("cannot read nodes for ino %u, returned error is %d\n", f->inocache->ino, ret); @@ -693,74 +1149,42 @@ static int jffs2_do_read_inode_internal(struct jffs2_sb_info *c, jffs2_set_inocache_state(c, f->inocache, INO_STATE_CHECKEDABSENT); return ret; } - f->dents = fd_list; - - rb = rb_first(&tn_list); - while (rb) { - cond_resched(); - tn = rb_entry(rb, struct jffs2_tmp_dnode_info, rb); - fn = tn->fn; - ret = 1; - dbg_readinode("consider node ver %u, phys offset " - "%#08x(%d), range %u-%u.\n", tn->version, - ref_offset(fn->raw), ref_flags(fn->raw), - fn->ofs, fn->ofs + fn->size); - - if (fn->size) { - ret = jffs2_add_older_frag_to_fragtree(c, f, tn); - /* TODO: the error code isn't checked, check it */ - jffs2_dbg_fragtree_paranoia_check_nolock(f); - BUG_ON(ret < 0); - if (!first_fn && ret == 0) - first_fn = fn; - } else if (!first_fn) { - first_fn = fn; - f->metadata = fn; - ret = 0; /* Prevent freeing the metadata update node */ - } else - jffs2_mark_node_obsolete(c, fn->raw); - - BUG_ON(rb->rb_left); - if (rb_parent(rb) && rb_parent(rb)->rb_left == rb) { - /* We were then left-hand child of our parent. We need - * to move our own right-hand child into our place. */ - repl_rb = rb->rb_right; - if (repl_rb) - rb_set_parent(repl_rb, rb_parent(rb)); - } else - repl_rb = NULL; - - rb = rb_next(rb); - - /* Remove the spent tn from the tree; don't bother rebalancing - * but put our right-hand child in our own place. */ - if (rb_parent(&tn->rb)) { - if (rb_parent(&tn->rb)->rb_left == &tn->rb) - rb_parent(&tn->rb)->rb_left = repl_rb; - else if (rb_parent(&tn->rb)->rb_right == &tn->rb) - rb_parent(&tn->rb)->rb_right = repl_rb; - else BUG(); - } else if (tn->rb.rb_right) - rb_set_parent(tn->rb.rb_right, NULL); + ret = jffs2_build_inode_fragtree(c, f, &rii); + if (ret) { + JFFS2_ERROR("Failed to build final fragtree for inode #%u: error %d\n", + f->inocache->ino, ret); + if (f->inocache->state == INO_STATE_READING) + jffs2_set_inocache_state(c, f->inocache, INO_STATE_CHECKEDABSENT); + jffs2_free_tmp_dnode_info_list(&rii.tn_root); + /* FIXME: We could at least crc-check them all */ + if (rii.mdata_tn) { + jffs2_free_full_dnode(rii.mdata_tn->fn); + jffs2_free_tmp_dnode_info(rii.mdata_tn); + rii.mdata_tn = NULL; + } + return ret; + } - jffs2_free_tmp_dnode_info(tn); - if (ret) { - dbg_readinode("delete dnode %u-%u.\n", - fn->ofs, fn->ofs + fn->size); - jffs2_free_full_dnode(fn); + if (rii.mdata_tn) { + if (rii.mdata_tn->fn->raw == rii.latest_ref) { + f->metadata = rii.mdata_tn->fn; + jffs2_free_tmp_dnode_info(rii.mdata_tn); + } else { + jffs2_kill_tn(c, rii.mdata_tn); } + rii.mdata_tn = NULL; } - jffs2_dbg_fragtree_paranoia_check_nolock(f); - BUG_ON(first_fn && ref_obsolete(first_fn->raw)); + f->dents = rii.fds; - fn = first_fn; - if (unlikely(!first_fn)) { + jffs2_dbg_fragtree_paranoia_check_nolock(f); + + if (unlikely(!rii.latest_ref)) { /* No data nodes for this inode. */ if (f->inocache->ino != 1) { JFFS2_WARNING("no data nodes found for ino #%u\n", f->inocache->ino); - if (!fd_list) { + if (!rii.fds) { if (f->inocache->state == INO_STATE_READING) jffs2_set_inocache_state(c, f->inocache, INO_STATE_CHECKEDABSENT); return -EIO; @@ -778,7 +1202,7 @@ static int jffs2_do_read_inode_internal(struct jffs2_sb_info *c, return 0; } - ret = jffs2_flash_read(c, ref_offset(fn->raw), sizeof(*latest_node), &retlen, (void *)latest_node); + ret = jffs2_flash_read(c, ref_offset(rii.latest_ref), sizeof(*latest_node), &retlen, (void *)latest_node); if (ret || retlen != sizeof(*latest_node)) { JFFS2_ERROR("failed to read from flash: error %d, %zd of %zd bytes read\n", ret, retlen, sizeof(*latest_node)); @@ -791,7 +1215,7 @@ static int jffs2_do_read_inode_internal(struct jffs2_sb_info *c, crc = crc32(0, latest_node, sizeof(*latest_node)-8); if (crc != je32_to_cpu(latest_node->node_crc)) { JFFS2_ERROR("CRC failed for read_inode of inode %u at physical location 0x%x\n", - f->inocache->ino, ref_offset(fn->raw)); + f->inocache->ino, ref_offset(rii.latest_ref)); up(&f->sem); jffs2_do_clear_inode(c, f); return -EIO; @@ -799,17 +1223,22 @@ static int jffs2_do_read_inode_internal(struct jffs2_sb_info *c, switch(jemode_to_cpu(latest_node->mode) & S_IFMT) { case S_IFDIR: - if (mctime_ver > je32_to_cpu(latest_node->version)) { + if (rii.mctime_ver > je32_to_cpu(latest_node->version)) { /* The times in the latest_node are actually older than mctime in the latest dirent. Cheat. */ - latest_node->ctime = latest_node->mtime = cpu_to_je32(latest_mctime); + latest_node->ctime = latest_node->mtime = cpu_to_je32(rii.latest_mctime); } break; case S_IFREG: /* If it was a regular file, truncate it to the latest node's isize */ - jffs2_truncate_fragtree(c, &f->fragtree, je32_to_cpu(latest_node->isize)); + new_size = jffs2_truncate_fragtree(c, &f->fragtree, je32_to_cpu(latest_node->isize)); + if (new_size != je32_to_cpu(latest_node->isize)) { + JFFS2_WARNING("Truncating ino #%u to %d bytes failed because it only had %d bytes to start with!\n", + f->inocache->ino, je32_to_cpu(latest_node->isize), new_size); + latest_node->isize = cpu_to_je32(new_size); + } break; case S_IFLNK: @@ -832,7 +1261,7 @@ static int jffs2_do_read_inode_internal(struct jffs2_sb_info *c, return -ENOMEM; } - ret = jffs2_flash_read(c, ref_offset(fn->raw) + sizeof(*latest_node), + ret = jffs2_flash_read(c, ref_offset(rii.latest_ref) + sizeof(*latest_node), je32_to_cpu(latest_node->csize), &retlen, (char *)f->target); if (ret || retlen != je32_to_cpu(latest_node->csize)) { |