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-rw-r--r--fs/jffs2/readinode.c1401
1 files changed, 1401 insertions, 0 deletions
diff --git a/fs/jffs2/readinode.c b/fs/jffs2/readinode.c
new file mode 100644
index 0000000000..0fe67cbb6b
--- /dev/null
+++ b/fs/jffs2/readinode.c
@@ -0,0 +1,1401 @@
+/*
+ * 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 <common.h>
+#include <crc.h>
+#include <fs.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/pagemap.h>
+#include <linux/mtd/mtd.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);
+
+ 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);
+
+ 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);
+ 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;
+ }
+ }
+
+ 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_IWUSR);
+ 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);
+ }
+
+ /* fall through... */
+
+ 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);
+
+ 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:
+ break;
+ 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);
+}