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-rw-r--r--fs/jffs2/readinode.c851
1 files changed, 640 insertions, 211 deletions
diff --git a/fs/jffs2/readinode.c b/fs/jffs2/readinode.c
index 717a48c..6aff389 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)) {
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