diff options
Diffstat (limited to '')
| -rw-r--r-- | fs/jffs2/readinode.c | 1447 |
1 files changed, 1447 insertions, 0 deletions
diff --git a/fs/jffs2/readinode.c b/fs/jffs2/readinode.c new file mode 100644 index 000000000..03b4f9961 --- /dev/null +++ b/fs/jffs2/readinode.c @@ -0,0 +1,1447 @@ +/* + * JFFS2 -- Journalling Flash File System, Version 2. + * + * Copyright © 2001-2007 Red Hat, Inc. + * + * Created by David Woodhouse <dwmw2@infradead.org> + * + * For licensing information, see the file 'LICENCE' in this directory. + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/fs.h> +#include <linux/crc32.h> +#include <linux/pagemap.h> +#include <linux/mtd/mtd.h> +#include <linux/compiler.h> +#include "nodelist.h" + +/* + * Check the data CRC of the node. + * + * Returns: 0 if the data CRC is correct; + * 1 - if incorrect; + * error code if an error occurred. + */ +static int check_node_data(struct jffs2_sb_info *c, struct jffs2_tmp_dnode_info *tn) +{ + 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); + + /* Calculate how many bytes were already checked */ + ofs = ref_offset(ref) + sizeof(struct jffs2_raw_inode); + len = tn->csize; + + if (jffs2_is_writebuffered(c)) { + int adj = ofs % c->wbuf_pagesize; + if (likely(adj)) + adj = c->wbuf_pagesize - adj; + + if (adj >= 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 += adj; + len -= adj; + } + + 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. */ + err = mtd_point(c->mtd, ofs, len, &retlen, (void **)&buffer, NULL); + if (!err && retlen < len) { + JFFS2_WARNING("MTD point returned len too short: %zu instead of %u.\n", retlen, tn->csize); + mtd_unpoint(c->mtd, ofs, retlen); + } else if (err) { + if (err != -EOPNOTSUPP) + JFFS2_WARNING("MTD point failed: error code %d.\n", err); + } else + 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 + mtd_unpoint(c->mtd, ofs, len); +#endif + + if (crc != tn->data_crc) { + JFFS2_NOTICE("wrong data CRC in data node at 0x%08x: read %#08x, calculated %#08x.\n", + ref_offset(ref), tn->data_crc, crc); + return 1; + } + +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 + mtd_unpoint(c->mtd, 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 handled (including marking it obsolete) + * < 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 *this, *ptn; + + dbg_readinode("insert fragment %#04x-%#04x, ver %u at %08x\n", tn->fn->ofs, fn_end, tn->version, ref_offset(tn->fn->raw)); + + /* If a node has zero dsize, we only have to keep 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) { + if (rii->mdata_tn->version < tn->version) { + /* 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); + } else { + dbg_readinode("kill new mdata with ver %d (older than existing %d\n", + tn->version, rii->mdata_tn->version); + jffs2_kill_tn(c, tn); + return 0; + } + } + 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) { + /* If the node is coincident with another at a lower address, + back up until the other node is found. It may be relevant */ + while (this->overlapped) { + ptn = tn_prev(this); + if (!ptn) { + /* + * We killed a node which set the overlapped + * flags during the scan. Fix it up. + */ + this->overlapped = 0; + break; + } + this = ptn; + } + 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. */ + dbg_readinode("Like new node. Throw away old\n"); + rb_replace_node(&this->rb, &tn->rb, &rii->tn_root); + jffs2_kill_tn(c, this); + /* Same overlapping from in front and behind */ + 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' and any subsequent nodes which are also overlapped */ + 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 killing overlapped nodes\n"); + continue; + } + 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... */ + dbg_readinode("Bad CRC on old overlapping node. Kill it\n"); + tn_erase(this, &rii->tn_root); + jffs2_kill_tn(c, this); + break; + } + + this = tn_next(this); + } + + /* We neither completely obsoleted nor were completely + obsoleted by an earlier node. Insert into the tree */ + { + struct rb_node *parent; + struct rb_node **link = &rii->tn_root.rb_node; + struct jffs2_tmp_dnode_info *insert_point = NULL; + + 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; + + ptn = tn_prev(this); + if (!ptn) { + /* + * We killed a node which set the overlapped + * flags during the scan. Fix it up. + */ + this->overlapped = 0; + break; + } + this = ptn; + } + } + + /* 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 child — so can be removed just by making its left-hand + child (if any) take its place under its parent. Since this is only done + when we're consuming the whole tree, there's no need to use rb_erase() + and let it worry about adjusting colours and balancing the tree. That + would just be a waste of time. */ +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; + if (node->rb_left) + node->rb_left->__rb_parent_color = node->__rb_parent_color; +} + +/* We put the version tree in reverse order, so we can use the same eat_last() + function that we use to consume the tmpnode tree (tn_root). */ +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)) { + if (pen) + continue; + /* + * We killed a node which set the overlapped + * flags during the scan. Fix it up. + */ + last->overlapped = 0; + } + + /* 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 %d, 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 %d, 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) +{ + struct jffs2_tmp_dnode_info *tn, *next; + + rbtree_postorder_for_each_entry_safe(tn, next, list, rb) { + jffs2_free_full_dnode(tn->fn); + jffs2_free_tmp_dnode_info(tn); + } + + *list = RB_ROOT; +} + +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; + dbg_noderef("node at 0x%08x is obsoleted. Ignoring.\n", ref_offset(ref)); + ref = ref->next_in_ino; + } + return NULL; +} + +/* + * Helper function for jffs2_get_inode_nodes(). + * It is called every time an directory entry node is found. + * + * Returns: 0 on success; + * 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_readinode_info *rii) +{ + struct jffs2_full_dirent *fd; + uint32_t crc; + + /* Obsoleted. This cannot happen, surely? dwmw2 20020308 */ + BUG_ON(ref_obsolete(ref)); + + crc = crc32(0, rd, sizeof(*rd) - 8); + 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); + jffs2_mark_node_obsolete(c, ref); + return 0; + } + + /* If we've never checked the CRCs on this node, check them now */ + if (ref_flags(ref) == REF_UNCHECKED) { + struct jffs2_eraseblock *jeb; + int len; + + /* Sanity check */ + 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)); + jffs2_mark_node_obsolete(c, ref); + return 0; + } + + jeb = &c->blocks[ref->flash_offset / c->sector_size]; + len = ref_totlen(c, jeb, ref); + + spin_lock(&c->erase_completion_lock); + jeb->used_size += len; + jeb->unchecked_size -= len; + c->used_size += len; + c->unchecked_size -= len; + ref->flash_offset = ref_offset(ref) | dirent_node_state(rd); + spin_unlock(&c->erase_completion_lock); + } + + fd = jffs2_alloc_full_dirent(rd->nsize + 1); + if (unlikely(!fd)) + return -ENOMEM; + + fd->raw = ref; + fd->version = je32_to_cpu(rd->version); + 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 > rii->mctime_ver && je32_to_cpu(rd->mctime)) { + rii->mctime_ver = fd->version; + rii->latest_mctime = je32_to_cpu(rd->mctime); + } + + /* + * Copy as much of the name as possible from the raw + * dirent we've already read from the flash. + */ + if (read > sizeof(*rd)) + memcpy(&fd->name[0], &rd->name[0], + min_t(uint32_t, rd->nsize, (read - sizeof(*rd)) )); + + /* Do we need to copy any more of the name directly from the flash? */ + if (rd->nsize + sizeof(*rd) > read) { + /* FIXME: point() */ + int err; + int already = read - sizeof(*rd); + + err = jffs2_flash_read(c, (ref_offset(ref)) + read, + rd->nsize - already, &read, &fd->name[already]); + if (unlikely(read != rd->nsize - already) && likely(!err)) { + jffs2_free_full_dirent(fd); + JFFS2_ERROR("short read: wanted %d bytes, got %zd\n", + rd->nsize - already, read); + return -EIO; + } + + if (unlikely(err)) { + JFFS2_ERROR("read remainder of name: error %d\n", err); + jffs2_free_full_dirent(fd); + return -EIO; + } + +#ifdef CONFIG_JFFS2_SUMMARY + /* + * we use CONFIG_JFFS2_SUMMARY because without it, we + * have checked it while mounting + */ + crc = crc32(0, fd->name, rd->nsize); + if (unlikely(crc != je32_to_cpu(rd->name_crc))) { + JFFS2_NOTICE("name CRC failed on dirent node at" + "%#08x: read %#08x,calculated %#08x\n", + ref_offset(ref), je32_to_cpu(rd->node_crc), crc); + jffs2_mark_node_obsolete(c, ref); + jffs2_free_full_dirent(fd); + return 0; + } +#endif + } + + fd->nhash = full_name_hash(NULL, fd->name, rd->nsize); + fd->next = NULL; + fd->name[rd->nsize] = '\0'; + + /* + * 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, &rii->fds); + + return 0; +} + +/* + * Helper function for jffs2_get_inode_nodes(). + * It is called every time an inode node is found. + * + * Returns: 0 on success (possibly after marking a bad node 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, int rdlen, + struct jffs2_readinode_info *rii) +{ + struct jffs2_tmp_dnode_info *tn; + uint32_t len, csize; + int ret = 0; + uint32_t crc; + + /* Obsoleted. This cannot happen, surely? dwmw2 20020308 */ + BUG_ON(ref_obsolete(ref)); + + crc = crc32(0, rd, sizeof(*rd) - 8); + 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); + jffs2_mark_node_obsolete(c, ref); + return 0; + } + + tn = jffs2_alloc_tmp_dnode_info(); + if (!tn) { + JFFS2_ERROR("failed to allocate tn (%zu bytes).\n", sizeof(*tn)); + return -ENOMEM; + } + + tn->partial_crc = 0; + csize = je32_to_cpu(rd->csize); + + /* If we've never checked the CRCs on this node, check them now */ + if (ref_flags(ref) == REF_UNCHECKED) { + + /* Sanity checks */ + if (unlikely(je32_to_cpu(rd->offset) > je32_to_cpu(rd->isize)) || + unlikely(PAD(je32_to_cpu(rd->csize) + sizeof(*rd)) != PAD(je32_to_cpu(rd->totlen)))) { + JFFS2_WARNING("inode node header CRC is corrupted at %#08x\n", ref_offset(ref)); + jffs2_dbg_dump_node(c, ref_offset(ref)); + jffs2_mark_node_obsolete(c, ref); + goto free_out; + } + + if (jffs2_is_writebuffered(c) && csize != 0) { + /* At this point we are supposed to check the data CRC + * of our unchecked node. But thus far, we do not + * know whether the node is valid or obsolete. To + * figure this out, we need to walk all the nodes of + * the inode and build the inode fragtree. We don't + * want to spend time checking data of nodes which may + * later be found to be obsolete. So we put off the full + * data CRC checking until we have read all the inode + * nodes and have started building the fragtree. + * + * The fragtree is being built starting with nodes + * having the highest version number, so we'll be able + * to detect whether a node is valid (i.e., it is not + * overlapped by a node with higher version) or not. + * And we'll be able to check only those nodes, which + * are not obsolete. + * + * Of course, this optimization only makes sense in case + * of NAND flashes (or other flashes with + * !jffs2_can_mark_obsolete()), since on NOR flashes + * nodes are marked obsolete physically. + * + * Since NAND flashes (or other flashes with + * jffs2_is_writebuffered(c)) are anyway read by + * fractions of c->wbuf_pagesize, and we have just read + * the node header, it is likely that the starting part + * of the node data is also read when we read the + * header. So we don't mind to check the CRC of the + * starting part of the data of the node now, and check + * the second part later (in jffs2_check_node_data()). + * Of course, we will not need to re-read and re-check + * the NAND page which we have just read. This is why we + * read the whole NAND page at jffs2_get_inode_nodes(), + * while we needed only the node header. + */ + unsigned char *buf; + + /* 'buf' will point to the start of data */ + buf = (unsigned char *)rd + sizeof(*rd); + /* len will be the read data length */ + len = min_t(uint32_t, rdlen - sizeof(*rd), csize); + tn->partial_crc = crc32(0, buf, len); + + dbg_readinode("Calculates CRC (%#08x) for %d bytes, csize %d\n", tn->partial_crc, len, csize); + + /* If we actually calculated the whole data CRC + * and it is wrong, drop the node. */ + if (len >= csize && unlikely(tn->partial_crc != je32_to_cpu(rd->data_crc))) { + JFFS2_NOTICE("wrong data CRC in data node at 0x%08x: read %#08x, calculated %#08x.\n", + ref_offset(ref), tn->partial_crc, je32_to_cpu(rd->data_crc)); + jffs2_mark_node_obsolete(c, ref); + goto free_out; + } + + } else if (csize == 0) { + /* + * We checked the header CRC. If the node has no data, adjust + * the space accounting now. For other nodes this will be done + * later either when the node is marked obsolete or when its + * data is checked. + */ + struct jffs2_eraseblock *jeb; + + dbg_readinode("the node has no data.\n"); + jeb = &c->blocks[ref->flash_offset / c->sector_size]; + len = ref_totlen(c, jeb, ref); + + spin_lock(&c->erase_completion_lock); + jeb->used_size += len; + jeb->unchecked_size -= len; + c->used_size += len; + c->unchecked_size -= len; + ref->flash_offset = ref_offset(ref) | REF_NORMAL; + spin_unlock(&c->erase_completion_lock); + } + } + + tn->fn = jffs2_alloc_full_dnode(); + if (!tn->fn) { + JFFS2_ERROR("alloc fn failed\n"); + ret = -ENOMEM; + goto free_out; + } + + tn->version = je32_to_cpu(rd->version); + tn->fn->ofs = je32_to_cpu(rd->offset); + 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 */ + if (rd->compr == JFFS2_COMPR_ZERO && !je32_to_cpu(rd->dsize) && csize) + tn->fn->size = csize; + else // normal case... + tn->fn->size = je32_to_cpu(rd->dsize); + + dbg_readinode2("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); + + 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_READINODE2_MESSAGES + dbg_readinode2("After adding ver %d:\n", je32_to_cpu(rd->version)); + tn = tn_first(&rii->tn_root); + while (tn) { + dbg_readinode2("%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; +} + +/* + * Helper function for jffs2_get_inode_nodes(). + * It is called every time an unknown node is found. + * + * Returns: 0 on success; + * negative error code on failure. + */ +static inline int read_unknown(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, struct jffs2_unknown_node *un) +{ + /* We don't mark unknown nodes as REF_UNCHECKED */ + if (ref_flags(ref) == REF_UNCHECKED) { + JFFS2_ERROR("REF_UNCHECKED but unknown node at %#08x\n", + ref_offset(ref)); + 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)); + jffs2_mark_node_obsolete(c, ref); + return 0; + } + + un->nodetype = cpu_to_je16(JFFS2_NODE_ACCURATE | je16_to_cpu(un->nodetype)); + + switch(je16_to_cpu(un->nodetype) & JFFS2_COMPAT_MASK) { + + case JFFS2_FEATURE_INCOMPAT: + JFFS2_ERROR("unknown INCOMPAT nodetype %#04X at %#08x\n", + je16_to_cpu(un->nodetype), ref_offset(ref)); + /* EEP */ + BUG(); + break; + + case JFFS2_FEATURE_ROCOMPAT: + JFFS2_ERROR("unknown ROCOMPAT nodetype %#04X at %#08x\n", + je16_to_cpu(un->nodetype), ref_offset(ref)); + BUG_ON(!(c->flags & JFFS2_SB_FLAG_RO)); + break; + + case JFFS2_FEATURE_RWCOMPAT_COPY: + JFFS2_NOTICE("unknown RWCOMPAT_COPY nodetype %#04X at %#08x\n", + je16_to_cpu(un->nodetype), ref_offset(ref)); + break; + + case JFFS2_FEATURE_RWCOMPAT_DELETE: + JFFS2_NOTICE("unknown RWCOMPAT_DELETE nodetype %#04X at %#08x\n", + je16_to_cpu(un->nodetype), ref_offset(ref)); + jffs2_mark_node_obsolete(c, ref); + return 0; + } + + return 0; +} + +/* + * Helper function for jffs2_get_inode_nodes(). + * The function detects whether more data should be read and reads it if yes. + * + * Returns: 0 on success; + * negative error code on failure. + */ +static int read_more(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, + int needed_len, int *rdlen, unsigned char *buf) +{ + int err, to_read = needed_len - *rdlen; + size_t retlen; + uint32_t offs; + + if (jffs2_is_writebuffered(c)) { + int rem = to_read % c->wbuf_pagesize; + + if (rem) + to_read += c->wbuf_pagesize - rem; + } + + /* We need to read more data */ + offs = ref_offset(ref) + *rdlen; + + dbg_readinode("read more %d bytes\n", to_read); + + 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", to_read, offs, err); + return err; + } + + if (retlen < to_read) { + JFFS2_ERROR("short read at %#08x: %zu instead of %d.\n", + offs, retlen, to_read); + return -EIO; + } + + *rdlen += to_read; + return 0; +} + +/* Get tmp_dnode_info and full_dirent for all non-obsolete nodes associated + 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 jffs2_readinode_info *rii) +{ + struct jffs2_raw_node_ref *ref, *valid_ref; + unsigned char *buf = NULL; + union jffs2_node_union *node; + size_t retlen; + int len, err; + + rii->mctime_ver = 0; + + dbg_readinode("ino #%u\n", f->inocache->ino); + + /* 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; + + spin_lock(&c->erase_completion_lock); + valid_ref = jffs2_first_valid_node(f->inocache->nodes); + if (!valid_ref && f->inocache->ino != 1) + JFFS2_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(); + + /* + * 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 header is + * of size = JFFS2_MIN_NODE_HEADER. + */ + len = JFFS2_MIN_NODE_HEADER; + if (jffs2_is_writebuffered(c)) { + int end, rem; + + /* + * 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. + */ + 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, 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; + } + + if (retlen < len) { + JFFS2_ERROR("short read at %#08x: %zu instead of %d.\n", ref_offset(ref), retlen, len); + err = -EIO; + goto free_out; + } + + 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)) { + JFFS2_NOTICE("Node header CRC failed at %#08x. {%04x,%04x,%08x,%08x}\n", + ref_offset(ref), 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_dbg_dump_node(c, ref_offset(ref)); + jffs2_mark_node_obsolete(c, ref); + goto cont; + } + 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; + } + + switch (je16_to_cpu(node->u.nodetype)) { + + case JFFS2_NODETYPE_DIRENT: + + if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_raw_dirent) && + len < sizeof(struct jffs2_raw_dirent)) { + 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, rii); + if (unlikely(err)) + goto free_out; + + break; + + case JFFS2_NODETYPE_INODE: + + if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_raw_inode) && + len < sizeof(struct jffs2_raw_inode)) { + 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, len, rii); + if (unlikely(err)) + goto free_out; + + break; + + default: + if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_unknown_node) && + len < sizeof(struct jffs2_unknown_node)) { + err = read_more(c, ref, sizeof(struct jffs2_unknown_node), &len, buf); + if (unlikely(err)) + goto free_out; + } + + err = read_unknown(c, ref, &node->u); + if (unlikely(err)) + goto free_out; + + } + cont: + spin_lock(&c->erase_completion_lock); + } + + spin_unlock(&c->erase_completion_lock); + 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, rii->highest_version, rii->latest_mctime, + rii->mctime_ver); + return 0; + + free_out: + jffs2_free_tmp_dnode_info_list(&rii->tn_root); + jffs2_free_full_dirent_list(rii->fds); + rii->fds = NULL; + kfree(buf); + return err; +} + +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_readinode_info rii; + uint32_t crc, new_size; + size_t retlen; + int ret; + + dbg_readinode("ino #%u pino/nlink is %d\n", f->inocache->ino, + f->inocache->pino_nlink); + + memset(&rii, 0, sizeof(rii)); + + /* Grab all nodes relevant to this ino */ + 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); + if (f->inocache->state == INO_STATE_READING) + jffs2_set_inocache_state(c, f->inocache, INO_STATE_CHECKEDABSENT); + return ret; + } + + 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; + } + + 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; + } + + f->dents = rii.fds; + + 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 (!rii.fds) { + if (f->inocache->state == INO_STATE_READING) + jffs2_set_inocache_state(c, f->inocache, INO_STATE_CHECKEDABSENT); + return -EIO; + } + JFFS2_NOTICE("but it has children so we fake some modes for it\n"); + } + latest_node->mode = cpu_to_jemode(S_IFDIR|S_IRUGO|S_IWUSR|S_IXUGO); + latest_node->version = cpu_to_je32(0); + latest_node->atime = latest_node->ctime = latest_node->mtime = cpu_to_je32(0); + latest_node->isize = cpu_to_je32(0); + latest_node->gid = cpu_to_je16(0); + latest_node->uid = cpu_to_je16(0); + if (f->inocache->state == INO_STATE_READING) + jffs2_set_inocache_state(c, f->inocache, INO_STATE_PRESENT); + return 0; + } + + 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)); + /* FIXME: If this fails, there seems to be a memory leak. Find it. */ + return ret ? ret : -EIO; + } + + 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(rii.latest_ref)); + return -EIO; + } + + switch(jemode_to_cpu(latest_node->mode) & S_IFMT) { + case S_IFDIR: + 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(rii.latest_mctime); + } + break; + + + case S_IFREG: + /* If it was a regular file, truncate it to the latest node's 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: + /* Hack to work around broken isize in old symlink code. + Remove this when dwmw2 comes to his senses and stops + symlinks from being an entirely gratuitous special + case. */ + if (!je32_to_cpu(latest_node->isize)) + latest_node->isize = latest_node->dsize; + + if (f->inocache->state != INO_STATE_CHECKING) { + /* Symlink's inode data is the target path. Read it and + * keep in RAM to facilitate quick follow symlink + * operation. */ + uint32_t csize = je32_to_cpu(latest_node->csize); + if (csize > JFFS2_MAX_NAME_LEN) + return -ENAMETOOLONG; + f->target = kmalloc(csize + 1, GFP_KERNEL); + if (!f->target) { + JFFS2_ERROR("can't allocate %u bytes of memory for the symlink target path cache\n", csize); + return -ENOMEM; + } + + ret = jffs2_flash_read(c, ref_offset(rii.latest_ref) + sizeof(*latest_node), + csize, &retlen, (char *)f->target); + + if (ret || retlen != csize) { + if (retlen != csize) + ret = -EIO; + kfree(f->target); + f->target = NULL; + return ret; + } + + f->target[csize] = '\0'; + dbg_readinode("symlink's target '%s' cached\n", f->target); + } + + fallthrough; + + case S_IFBLK: + case S_IFCHR: + /* Certain inode types should have only one data node, and it's + kept as the metadata node */ + if (f->metadata) { + JFFS2_ERROR("Argh. Special inode #%u with mode 0%o had metadata node\n", + f->inocache->ino, jemode_to_cpu(latest_node->mode)); + return -EIO; + } + if (!frag_first(&f->fragtree)) { + JFFS2_ERROR("Argh. Special inode #%u with mode 0%o has no fragments\n", + f->inocache->ino, jemode_to_cpu(latest_node->mode)); + return -EIO; + } + /* ASSERT: f->fraglist != NULL */ + if (frag_next(frag_first(&f->fragtree))) { + JFFS2_ERROR("Argh. Special inode #%u with mode 0x%x had more than one node\n", + f->inocache->ino, jemode_to_cpu(latest_node->mode)); + /* FIXME: Deal with it - check crc32, check for duplicate node, check times and discard the older one */ + return -EIO; + } + /* OK. We're happy */ + f->metadata = frag_first(&f->fragtree)->node; + jffs2_free_node_frag(frag_first(&f->fragtree)); + f->fragtree = RB_ROOT; + break; + } + if (f->inocache->state == INO_STATE_READING) + jffs2_set_inocache_state(c, f->inocache, INO_STATE_PRESENT); + + return 0; +} + +/* Scan the list of all nodes present for this ino, build map of versions, etc. */ +int jffs2_do_read_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, + uint32_t ino, struct jffs2_raw_inode *latest_node) +{ + dbg_readinode("read inode #%u\n", ino); + + retry_inocache: + spin_lock(&c->inocache_lock); + f->inocache = jffs2_get_ino_cache(c, ino); + + if (f->inocache) { + /* Check its state. We may need to wait before we can use it */ + switch(f->inocache->state) { + case INO_STATE_UNCHECKED: + case INO_STATE_CHECKEDABSENT: + f->inocache->state = INO_STATE_READING; + break; + + case INO_STATE_CHECKING: + case INO_STATE_GC: + /* If it's in either of these states, we need + to wait for whoever's got it to finish and + put it back. */ + dbg_readinode("waiting for ino #%u in state %d\n", ino, f->inocache->state); + sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock); + goto retry_inocache; + + case INO_STATE_READING: + case INO_STATE_PRESENT: + /* Eep. This should never happen. It can + happen if Linux calls read_inode() again + before clear_inode() has finished though. */ + JFFS2_ERROR("Eep. Trying to read_inode #%u when it's already in state %d!\n", ino, f->inocache->state); + /* Fail. That's probably better than allowing it to succeed */ + f->inocache = NULL; + break; + + default: + BUG(); + } + } + spin_unlock(&c->inocache_lock); + + if (!f->inocache && ino == 1) { + /* Special case - no root inode on medium */ + f->inocache = jffs2_alloc_inode_cache(); + if (!f->inocache) { + JFFS2_ERROR("cannot allocate inocache for root inode\n"); + return -ENOMEM; + } + dbg_readinode("creating inocache for root inode\n"); + memset(f->inocache, 0, sizeof(struct jffs2_inode_cache)); + f->inocache->ino = f->inocache->pino_nlink = 1; + f->inocache->nodes = (struct jffs2_raw_node_ref *)f->inocache; + f->inocache->state = INO_STATE_READING; + jffs2_add_ino_cache(c, f->inocache); + } + if (!f->inocache) { + JFFS2_ERROR("requested to read a nonexistent ino %u\n", ino); + return -ENOENT; + } + + return jffs2_do_read_inode_internal(c, f, latest_node); +} + +int jffs2_do_crccheck_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic) +{ + struct jffs2_raw_inode n; + struct jffs2_inode_info *f = kzalloc(sizeof(*f), GFP_KERNEL); + int ret; + + if (!f) + return -ENOMEM; + + mutex_init(&f->sem); + mutex_lock(&f->sem); + f->inocache = ic; + + ret = jffs2_do_read_inode_internal(c, f, &n); + mutex_unlock(&f->sem); + jffs2_do_clear_inode(c, f); + jffs2_xattr_do_crccheck_inode(c, ic); + kfree (f); + return ret; +} + +void jffs2_do_clear_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f) +{ + struct jffs2_full_dirent *fd, *fds; + int deleted; + + jffs2_xattr_delete_inode(c, f->inocache); + mutex_lock(&f->sem); + deleted = f->inocache && !f->inocache->pino_nlink; + + if (f->inocache && f->inocache->state != INO_STATE_CHECKING) + jffs2_set_inocache_state(c, f->inocache, INO_STATE_CLEARING); + + if (f->metadata) { + if (deleted) + jffs2_mark_node_obsolete(c, f->metadata->raw); + jffs2_free_full_dnode(f->metadata); + } + + jffs2_kill_fragtree(&f->fragtree, deleted?c:NULL); + + fds = f->dents; + while(fds) { + fd = fds; + fds = fd->next; + jffs2_free_full_dirent(fd); + } + + if (f->inocache && f->inocache->state != INO_STATE_CHECKING) { + jffs2_set_inocache_state(c, f->inocache, INO_STATE_CHECKEDABSENT); + if (f->inocache->nodes == (void *)f->inocache) + jffs2_del_ino_cache(c, f->inocache); + } + + mutex_unlock(&f->sem); +} |