--- /dev/null
+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright © 2001-2007 Red Hat, Inc.
+ * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
+ *
+ * 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/mtd/mtd.h>
+#include <linux/slab.h>
+#include <linux/pagemap.h>
+#include <linux/crc32.h>
+#include <linux/compiler.h>
+#include <linux/stat.h>
+#include "nodelist.h"
+#include "compr.h"
+
+static int jffs2_garbage_collect_pristine(struct jffs2_sb_info *c,
+ struct jffs2_inode_cache *ic,
+ struct jffs2_raw_node_ref *raw);
+static int jffs2_garbage_collect_metadata(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+ struct jffs2_inode_info *f, struct jffs2_full_dnode *fd);
+static int jffs2_garbage_collect_dirent(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+ struct jffs2_inode_info *f, struct jffs2_full_dirent *fd);
+static int jffs2_garbage_collect_deletion_dirent(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+ struct jffs2_inode_info *f, struct jffs2_full_dirent *fd);
+static int jffs2_garbage_collect_hole(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+ struct jffs2_inode_info *f, struct jffs2_full_dnode *fn,
+ uint32_t start, uint32_t end);
+static int jffs2_garbage_collect_dnode(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+ struct jffs2_inode_info *f, struct jffs2_full_dnode *fn,
+ uint32_t start, uint32_t end);
+static int jffs2_garbage_collect_live(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+ struct jffs2_raw_node_ref *raw, struct jffs2_inode_info *f);
+
+/* Called with erase_completion_lock held */
+static struct jffs2_eraseblock *jffs2_find_gc_block(struct jffs2_sb_info *c)
+{
+ struct jffs2_eraseblock *ret;
+ struct list_head *nextlist = NULL;
+ int n = jiffies % 128;
+
+ /* Pick an eraseblock to garbage collect next. This is where we'll
+ put the clever wear-levelling algorithms. Eventually. */
+ /* We possibly want to favour the dirtier blocks more when the
+ number of free blocks is low. */
+again:
+ if (!list_empty(&c->bad_used_list) && c->nr_free_blocks > c->resv_blocks_gcbad) {
+ jffs2_dbg(1, "Picking block from bad_used_list to GC next\n");
+ nextlist = &c->bad_used_list;
+ } else if (n < 50 && !list_empty(&c->erasable_list)) {
+ /* Note that most of them will have gone directly to be erased.
+ So don't favour the erasable_list _too_ much. */
+ jffs2_dbg(1, "Picking block from erasable_list to GC next\n");
+ nextlist = &c->erasable_list;
+ } else if (n < 110 && !list_empty(&c->very_dirty_list)) {
+ /* Most of the time, pick one off the very_dirty list */
+ jffs2_dbg(1, "Picking block from very_dirty_list to GC next\n");
+ nextlist = &c->very_dirty_list;
+ } else if (n < 126 && !list_empty(&c->dirty_list)) {
+ jffs2_dbg(1, "Picking block from dirty_list to GC next\n");
+ nextlist = &c->dirty_list;
+ } else if (!list_empty(&c->clean_list)) {
+ jffs2_dbg(1, "Picking block from clean_list to GC next\n");
+ nextlist = &c->clean_list;
+ } else if (!list_empty(&c->dirty_list)) {
+ jffs2_dbg(1, "Picking block from dirty_list to GC next (clean_list was empty)\n");
+
+ nextlist = &c->dirty_list;
+ } else if (!list_empty(&c->very_dirty_list)) {
+ jffs2_dbg(1, "Picking block from very_dirty_list to GC next (clean_list and dirty_list were empty)\n");
+ nextlist = &c->very_dirty_list;
+ } else if (!list_empty(&c->erasable_list)) {
+ jffs2_dbg(1, "Picking block from erasable_list to GC next (clean_list and {very_,}dirty_list were empty)\n");
+
+ nextlist = &c->erasable_list;
+ } else if (!list_empty(&c->erasable_pending_wbuf_list)) {
+ /* There are blocks are wating for the wbuf sync */
+ jffs2_dbg(1, "Synching wbuf in order to reuse erasable_pending_wbuf_list blocks\n");
+ spin_unlock(&c->erase_completion_lock);
+ jffs2_flush_wbuf_pad(c);
+ spin_lock(&c->erase_completion_lock);
+ goto again;
+ } else {
+ /* Eep. All were empty */
+ jffs2_dbg(1, "No clean, dirty _or_ erasable blocks to GC from! Where are they all?\n");
+ return NULL;
+ }
+
+ ret = list_entry(nextlist->next, struct jffs2_eraseblock, list);
+ list_del(&ret->list);
+ c->gcblock = ret;
+ ret->gc_node = ret->first_node;
+ if (!ret->gc_node) {
+ pr_warn("Eep. ret->gc_node for block at 0x%08x is NULL\n",
+ ret->offset);
+ BUG();
+ }
+
+ /* Have we accidentally picked a clean block with wasted space ? */
+ if (ret->wasted_size) {
+ jffs2_dbg(1, "Converting wasted_size %08x to dirty_size\n",
+ ret->wasted_size);
+ ret->dirty_size += ret->wasted_size;
+ c->wasted_size -= ret->wasted_size;
+ c->dirty_size += ret->wasted_size;
+ ret->wasted_size = 0;
+ }
+
+ return ret;
+}
+
+/* jffs2_garbage_collect_pass
+ * Make a single attempt to progress GC. Move one node, and possibly
+ * start erasing one eraseblock.
+ */
+int jffs2_garbage_collect_pass(struct jffs2_sb_info *c)
+{
+ struct jffs2_inode_info *f;
+ struct jffs2_inode_cache *ic;
+ struct jffs2_eraseblock *jeb;
+ struct jffs2_raw_node_ref *raw;
+ uint32_t gcblock_dirty;
+ int ret = 0, inum, nlink;
+ int xattr = 0;
+
+ if (mutex_lock_interruptible(&c->alloc_sem))
+ return -EINTR;
+
+ for (;;) {
+ spin_lock(&c->erase_completion_lock);
+ if (!c->unchecked_size)
+ break;
+
+ /* We can't start doing GC yet. We haven't finished checking
+ the node CRCs etc. Do it now. */
+
+ /* checked_ino is protected by the alloc_sem */
+ if (c->checked_ino > c->highest_ino && xattr) {
+ pr_crit("Checked all inodes but still 0x%x bytes of unchecked space?\n",
+ c->unchecked_size);
+ jffs2_dbg_dump_block_lists_nolock(c);
+ spin_unlock(&c->erase_completion_lock);
+ mutex_unlock(&c->alloc_sem);
+ return -ENOSPC;
+ }
+
+ spin_unlock(&c->erase_completion_lock);
+
+ if (!xattr)
+ xattr = jffs2_verify_xattr(c);
+
+ spin_lock(&c->inocache_lock);
+
+ ic = jffs2_get_ino_cache(c, c->checked_ino++);
+
+ if (!ic) {
+ spin_unlock(&c->inocache_lock);
+ continue;
+ }
+
+ if (!ic->pino_nlink) {
+ jffs2_dbg(1, "Skipping check of ino #%d with nlink/pino zero\n",
+ ic->ino);
+ spin_unlock(&c->inocache_lock);
+ jffs2_xattr_delete_inode(c, ic);
+ continue;
+ }
+ switch(ic->state) {
+ case INO_STATE_CHECKEDABSENT:
+ case INO_STATE_PRESENT:
+ jffs2_dbg(1, "Skipping ino #%u already checked\n",
+ ic->ino);
+ spin_unlock(&c->inocache_lock);
+ continue;
+
+ case INO_STATE_GC:
+ case INO_STATE_CHECKING:
+ pr_warn("Inode #%u is in state %d during CRC check phase!\n",
+ ic->ino, ic->state);
+ spin_unlock(&c->inocache_lock);
+ BUG();
+
+ case INO_STATE_READING:
+ /* We need to wait for it to finish, lest we move on
+ and trigger the BUG() above while we haven't yet
+ finished checking all its nodes */
+ jffs2_dbg(1, "Waiting for ino #%u to finish reading\n",
+ ic->ino);
+ /* We need to come back again for the _same_ inode. We've
+ made no progress in this case, but that should be OK */
+ c->checked_ino--;
+
+ mutex_unlock(&c->alloc_sem);
+ sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock);
+ return 0;
+
+ default:
+ BUG();
+
+ case INO_STATE_UNCHECKED:
+ ;
+ }
+ ic->state = INO_STATE_CHECKING;
+ spin_unlock(&c->inocache_lock);
+
+ jffs2_dbg(1, "%s(): triggering inode scan of ino#%u\n",
+ __func__, ic->ino);
+
+ ret = jffs2_do_crccheck_inode(c, ic);
+ if (ret)
+ pr_warn("Returned error for crccheck of ino #%u. Expect badness...\n",
+ ic->ino);
+
+ jffs2_set_inocache_state(c, ic, INO_STATE_CHECKEDABSENT);
+ mutex_unlock(&c->alloc_sem);
+ return ret;
+ }
+
+ /* If there are any blocks which need erasing, erase them now */
+ if (!list_empty(&c->erase_complete_list) ||
+ !list_empty(&c->erase_pending_list)) {
+ spin_unlock(&c->erase_completion_lock);
+ mutex_unlock(&c->alloc_sem);
+ jffs2_dbg(1, "%s(): erasing pending blocks\n", __func__);
+ if (jffs2_erase_pending_blocks(c, 1))
+ return 0;
+
+ jffs2_dbg(1, "No progress from erasing block; doing GC anyway\n");
+ mutex_lock(&c->alloc_sem);
+ spin_lock(&c->erase_completion_lock);
+ }
+
+ /* First, work out which block we're garbage-collecting */
+ jeb = c->gcblock;
+
+ if (!jeb)
+ jeb = jffs2_find_gc_block(c);
+
+ if (!jeb) {
+ /* Couldn't find a free block. But maybe we can just erase one and make 'progress'? */
+ if (c->nr_erasing_blocks) {
+ spin_unlock(&c->erase_completion_lock);
+ mutex_unlock(&c->alloc_sem);
+ return -EAGAIN;
+ }
+ jffs2_dbg(1, "Couldn't find erase block to garbage collect!\n");
+ spin_unlock(&c->erase_completion_lock);
+ mutex_unlock(&c->alloc_sem);
+ return -EIO;
+ }
+
+ jffs2_dbg(1, "GC from block %08x, used_size %08x, dirty_size %08x, free_size %08x\n",
+ jeb->offset, jeb->used_size, jeb->dirty_size, jeb->free_size);
+ D1(if (c->nextblock)
+ printk(KERN_DEBUG "Nextblock at %08x, used_size %08x, dirty_size %08x, wasted_size %08x, free_size %08x\n", c->nextblock->offset, c->nextblock->used_size, c->nextblock->dirty_size, c->nextblock->wasted_size, c->nextblock->free_size));
+
+ if (!jeb->used_size) {
+ mutex_unlock(&c->alloc_sem);
+ goto eraseit;
+ }
+
+ raw = jeb->gc_node;
+ gcblock_dirty = jeb->dirty_size;
+
+ while(ref_obsolete(raw)) {
+ jffs2_dbg(1, "Node at 0x%08x is obsolete... skipping\n",
+ ref_offset(raw));
+ raw = ref_next(raw);
+ if (unlikely(!raw)) {
+ pr_warn("eep. End of raw list while still supposedly nodes to GC\n");
+ pr_warn("erase block at 0x%08x. free_size 0x%08x, dirty_size 0x%08x, used_size 0x%08x\n",
+ jeb->offset, jeb->free_size,
+ jeb->dirty_size, jeb->used_size);
+ jeb->gc_node = raw;
+ spin_unlock(&c->erase_completion_lock);
+ mutex_unlock(&c->alloc_sem);
+ BUG();
+ }
+ }
+ jeb->gc_node = raw;
+
+ jffs2_dbg(1, "Going to garbage collect node at 0x%08x\n",
+ ref_offset(raw));
+
+ if (!raw->next_in_ino) {
+ /* Inode-less node. Clean marker, snapshot or something like that */
+ spin_unlock(&c->erase_completion_lock);
+ if (ref_flags(raw) == REF_PRISTINE) {
+ /* It's an unknown node with JFFS2_FEATURE_RWCOMPAT_COPY */
+ jffs2_garbage_collect_pristine(c, NULL, raw);
+ } else {
+ /* Just mark it obsolete */
+ jffs2_mark_node_obsolete(c, raw);
+ }
+ mutex_unlock(&c->alloc_sem);
+ goto eraseit_lock;
+ }
+
+ ic = jffs2_raw_ref_to_ic(raw);
+
+#ifdef CONFIG_JFFS2_FS_XATTR
+ /* When 'ic' refers xattr_datum/xattr_ref, this node is GCed as xattr.
+ * We can decide whether this node is inode or xattr by ic->class. */
+ if (ic->class == RAWNODE_CLASS_XATTR_DATUM
+ || ic->class == RAWNODE_CLASS_XATTR_REF) {
+ spin_unlock(&c->erase_completion_lock);
+
+ if (ic->class == RAWNODE_CLASS_XATTR_DATUM) {
+ ret = jffs2_garbage_collect_xattr_datum(c, (struct jffs2_xattr_datum *)ic, raw);
+ } else {
+ ret = jffs2_garbage_collect_xattr_ref(c, (struct jffs2_xattr_ref *)ic, raw);
+ }
+ goto test_gcnode;
+ }
+#endif
+
+ /* We need to hold the inocache. Either the erase_completion_lock or
+ the inocache_lock are sufficient; we trade down since the inocache_lock
+ causes less contention. */
+ spin_lock(&c->inocache_lock);
+
+ spin_unlock(&c->erase_completion_lock);
+
+ jffs2_dbg(1, "%s(): collecting from block @0x%08x. Node @0x%08x(%d), ino #%u\n",
+ __func__, jeb->offset, ref_offset(raw), ref_flags(raw),
+ ic->ino);
+
+ /* Three possibilities:
+ 1. Inode is already in-core. We must iget it and do proper
+ updating to its fragtree, etc.
+ 2. Inode is not in-core, node is REF_PRISTINE. We lock the
+ inocache to prevent a read_inode(), copy the node intact.
+ 3. Inode is not in-core, node is not pristine. We must iget()
+ and take the slow path.
+ */
+
+ switch(ic->state) {
+ case INO_STATE_CHECKEDABSENT:
+ /* It's been checked, but it's not currently in-core.
+ We can just copy any pristine nodes, but have
+ to prevent anyone else from doing read_inode() while
+ we're at it, so we set the state accordingly */
+ if (ref_flags(raw) == REF_PRISTINE)
+ ic->state = INO_STATE_GC;
+ else {
+ jffs2_dbg(1, "Ino #%u is absent but node not REF_PRISTINE. Reading.\n",
+ ic->ino);
+ }
+ break;
+
+ case INO_STATE_PRESENT:
+ /* It's in-core. GC must iget() it. */
+ break;
+
+ case INO_STATE_UNCHECKED:
+ case INO_STATE_CHECKING:
+ case INO_STATE_GC:
+ /* Should never happen. We should have finished checking
+ by the time we actually start doing any GC, and since
+ we're holding the alloc_sem, no other garbage collection
+ can happen.
+ */
+ pr_crit("Inode #%u already in state %d in jffs2_garbage_collect_pass()!\n",
+ ic->ino, ic->state);
+ mutex_unlock(&c->alloc_sem);
+ spin_unlock(&c->inocache_lock);
+ BUG();
+
+ case INO_STATE_READING:
+ /* Someone's currently trying to read it. We must wait for
+ them to finish and then go through the full iget() route
+ to do the GC. However, sometimes read_inode() needs to get
+ the alloc_sem() (for marking nodes invalid) so we must
+ drop the alloc_sem before sleeping. */
+
+ mutex_unlock(&c->alloc_sem);
+ jffs2_dbg(1, "%s(): waiting for ino #%u in state %d\n",
+ __func__, ic->ino, ic->state);
+ sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock);
+ /* And because we dropped the alloc_sem we must start again from the
+ beginning. Ponder chance of livelock here -- we're returning success
+ without actually making any progress.
+
+ Q: What are the chances that the inode is back in INO_STATE_READING
+ again by the time we next enter this function? And that this happens
+ enough times to cause a real delay?
+
+ A: Small enough that I don't care :)
+ */
+ return 0;
+ }
+
+ /* OK. Now if the inode is in state INO_STATE_GC, we are going to copy the
+ node intact, and we don't have to muck about with the fragtree etc.
+ because we know it's not in-core. If it _was_ in-core, we go through
+ all the iget() crap anyway */
+
+ if (ic->state == INO_STATE_GC) {
+ spin_unlock(&c->inocache_lock);
+
+ ret = jffs2_garbage_collect_pristine(c, ic, raw);
+
+ spin_lock(&c->inocache_lock);
+ ic->state = INO_STATE_CHECKEDABSENT;
+ wake_up(&c->inocache_wq);
+
+ if (ret != -EBADFD) {
+ spin_unlock(&c->inocache_lock);
+ goto test_gcnode;
+ }
+
+ /* Fall through if it wanted us to, with inocache_lock held */
+ }
+
+ /* Prevent the fairly unlikely race where the gcblock is
+ entirely obsoleted by the final close of a file which had
+ the only valid nodes in the block, followed by erasure,
+ followed by freeing of the ic because the erased block(s)
+ held _all_ the nodes of that inode.... never been seen but
+ it's vaguely possible. */
+
+ inum = ic->ino;
+ nlink = ic->pino_nlink;
+ spin_unlock(&c->inocache_lock);
+
+ f = jffs2_gc_fetch_inode(c, inum, !nlink);
+ if (IS_ERR(f)) {
+ ret = PTR_ERR(f);
+ goto release_sem;
+ }
+ if (!f) {
+ ret = 0;
+ goto release_sem;
+ }
+
+ ret = jffs2_garbage_collect_live(c, jeb, raw, f);
+
+ jffs2_gc_release_inode(c, f);
+
+ test_gcnode:
+ if (jeb->dirty_size == gcblock_dirty && !ref_obsolete(jeb->gc_node)) {
+ /* Eep. This really should never happen. GC is broken */
+ pr_err("Error garbage collecting node at %08x!\n",
+ ref_offset(jeb->gc_node));
+ ret = -ENOSPC;
+ }
+ release_sem:
+ mutex_unlock(&c->alloc_sem);
+
+ eraseit_lock:
+ /* If we've finished this block, start it erasing */
+ spin_lock(&c->erase_completion_lock);
+
+ eraseit:
+ if (c->gcblock && !c->gcblock->used_size) {
+ jffs2_dbg(1, "Block at 0x%08x completely obsoleted by GC. Moving to erase_pending_list\n",
+ c->gcblock->offset);
+ /* We're GC'ing an empty block? */
+ list_add_tail(&c->gcblock->list, &c->erase_pending_list);
+ c->gcblock = NULL;
+ c->nr_erasing_blocks++;
+ jffs2_garbage_collect_trigger(c);
+ }
+ spin_unlock(&c->erase_completion_lock);
+
+ return ret;
+}
+
+static int jffs2_garbage_collect_live(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+ struct jffs2_raw_node_ref *raw, struct jffs2_inode_info *f)
+{
+ struct jffs2_node_frag *frag;
+ struct jffs2_full_dnode *fn = NULL;
+ struct jffs2_full_dirent *fd;
+ uint32_t start = 0, end = 0, nrfrags = 0;
+ int ret = 0;
+
+ mutex_lock(&f->sem);
+
+ /* Now we have the lock for this inode. Check that it's still the one at the head
+ of the list. */
+
+ spin_lock(&c->erase_completion_lock);
+
+ if (c->gcblock != jeb) {
+ spin_unlock(&c->erase_completion_lock);
+ jffs2_dbg(1, "GC block is no longer gcblock. Restart\n");
+ goto upnout;
+ }
+ if (ref_obsolete(raw)) {
+ spin_unlock(&c->erase_completion_lock);
+ jffs2_dbg(1, "node to be GC'd was obsoleted in the meantime.\n");
+ /* They'll call again */
+ goto upnout;
+ }
+ spin_unlock(&c->erase_completion_lock);
+
+ /* OK. Looks safe. And nobody can get us now because we have the semaphore. Move the block */
+ if (f->metadata && f->metadata->raw == raw) {
+ fn = f->metadata;
+ ret = jffs2_garbage_collect_metadata(c, jeb, f, fn);
+ goto upnout;
+ }
+
+ /* FIXME. Read node and do lookup? */
+ for (frag = frag_first(&f->fragtree); frag; frag = frag_next(frag)) {
+ if (frag->node && frag->node->raw == raw) {
+ fn = frag->node;
+ end = frag->ofs + frag->size;
+ if (!nrfrags++)
+ start = frag->ofs;
+ if (nrfrags == frag->node->frags)
+ break; /* We've found them all */
+ }
+ }
+ if (fn) {
+ if (ref_flags(raw) == REF_PRISTINE) {
+ ret = jffs2_garbage_collect_pristine(c, f->inocache, raw);
+ if (!ret) {
+ /* Urgh. Return it sensibly. */
+ frag->node->raw = f->inocache->nodes;
+ }
+ if (ret != -EBADFD)
+ goto upnout;
+ }
+ /* We found a datanode. Do the GC */
+ if((start >> PAGE_CACHE_SHIFT) < ((end-1) >> PAGE_CACHE_SHIFT)) {
+ /* It crosses a page boundary. Therefore, it must be a hole. */
+ ret = jffs2_garbage_collect_hole(c, jeb, f, fn, start, end);
+ } else {
+ /* It could still be a hole. But we GC the page this way anyway */
+ ret = jffs2_garbage_collect_dnode(c, jeb, f, fn, start, end);
+ }
+ goto upnout;
+ }
+
+ /* Wasn't a dnode. Try dirent */
+ for (fd = f->dents; fd; fd=fd->next) {
+ if (fd->raw == raw)
+ break;
+ }
+
+ if (fd && fd->ino) {
+ ret = jffs2_garbage_collect_dirent(c, jeb, f, fd);
+ } else if (fd) {
+ ret = jffs2_garbage_collect_deletion_dirent(c, jeb, f, fd);
+ } else {
+ pr_warn("Raw node at 0x%08x wasn't in node lists for ino #%u\n",
+ ref_offset(raw), f->inocache->ino);
+ if (ref_obsolete(raw)) {
+ pr_warn("But it's obsolete so we don't mind too much\n");
+ } else {
+ jffs2_dbg_dump_node(c, ref_offset(raw));
+ BUG();
+ }
+ }
+ upnout:
+ mutex_unlock(&f->sem);
+
+ return ret;
+}
+
+static int jffs2_garbage_collect_pristine(struct jffs2_sb_info *c,
+ struct jffs2_inode_cache *ic,
+ struct jffs2_raw_node_ref *raw)
+{
+ union jffs2_node_union *node;
+ size_t retlen;
+ int ret;
+ uint32_t phys_ofs, alloclen;
+ uint32_t crc, rawlen;
+ int retried = 0;
+
+ jffs2_dbg(1, "Going to GC REF_PRISTINE node at 0x%08x\n",
+ ref_offset(raw));
+
+ alloclen = rawlen = ref_totlen(c, c->gcblock, raw);
+
+ /* Ask for a small amount of space (or the totlen if smaller) because we
+ don't want to force wastage of the end of a block if splitting would
+ work. */
+ if (ic && alloclen > sizeof(struct jffs2_raw_inode) + JFFS2_MIN_DATA_LEN)
+ alloclen = sizeof(struct jffs2_raw_inode) + JFFS2_MIN_DATA_LEN;
+
+ ret = jffs2_reserve_space_gc(c, alloclen, &alloclen, rawlen);
+ /* 'rawlen' is not the exact summary size; it is only an upper estimation */
+
+ if (ret)
+ return ret;
+
+ if (alloclen < rawlen) {
+ /* Doesn't fit untouched. We'll go the old route and split it */
+ return -EBADFD;
+ }
+
+ node = kmalloc(rawlen, GFP_KERNEL);
+ if (!node)
+ return -ENOMEM;
+
+ ret = jffs2_flash_read(c, ref_offset(raw), rawlen, &retlen, (char *)node);
+ if (!ret && retlen != rawlen)
+ ret = -EIO;
+ if (ret)
+ goto out_node;
+
+ crc = crc32(0, node, sizeof(struct jffs2_unknown_node)-4);
+ if (je32_to_cpu(node->u.hdr_crc) != crc) {
+ pr_warn("Header CRC failed on REF_PRISTINE node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
+ ref_offset(raw), je32_to_cpu(node->u.hdr_crc), crc);
+ goto bail;
+ }
+
+ switch(je16_to_cpu(node->u.nodetype)) {
+ case JFFS2_NODETYPE_INODE:
+ crc = crc32(0, node, sizeof(node->i)-8);
+ if (je32_to_cpu(node->i.node_crc) != crc) {
+ pr_warn("Node CRC failed on REF_PRISTINE data node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
+ ref_offset(raw), je32_to_cpu(node->i.node_crc),
+ crc);
+ goto bail;
+ }
+
+ if (je32_to_cpu(node->i.dsize)) {
+ crc = crc32(0, node->i.data, je32_to_cpu(node->i.csize));
+ if (je32_to_cpu(node->i.data_crc) != crc) {
+ pr_warn("Data CRC failed on REF_PRISTINE data node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
+ ref_offset(raw),
+ je32_to_cpu(node->i.data_crc), crc);
+ goto bail;
+ }
+ }
+ break;
+
+ case JFFS2_NODETYPE_DIRENT:
+ crc = crc32(0, node, sizeof(node->d)-8);
+ if (je32_to_cpu(node->d.node_crc) != crc) {
+ pr_warn("Node CRC failed on REF_PRISTINE dirent node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
+ ref_offset(raw),
+ je32_to_cpu(node->d.node_crc), crc);
+ goto bail;
+ }
+
+ if (strnlen(node->d.name, node->d.nsize) != node->d.nsize) {
+ pr_warn("Name in dirent node at 0x%08x contains zeroes\n",
+ ref_offset(raw));
+ goto bail;
+ }
+
+ if (node->d.nsize) {
+ crc = crc32(0, node->d.name, node->d.nsize);
+ if (je32_to_cpu(node->d.name_crc) != crc) {
+ pr_warn("Name CRC failed on REF_PRISTINE dirent node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
+ ref_offset(raw),
+ je32_to_cpu(node->d.name_crc), crc);
+ goto bail;
+ }
+ }
+ break;
+ default:
+ /* If it's inode-less, we don't _know_ what it is. Just copy it intact */
+ if (ic) {
+ pr_warn("Unknown node type for REF_PRISTINE node at 0x%08x: 0x%04x\n",
+ ref_offset(raw), je16_to_cpu(node->u.nodetype));
+ goto bail;
+ }
+ }
+
+ /* OK, all the CRCs are good; this node can just be copied as-is. */
+ retry:
+ phys_ofs = write_ofs(c);
+
+ ret = jffs2_flash_write(c, phys_ofs, rawlen, &retlen, (char *)node);
+
+ if (ret || (retlen != rawlen)) {
+ pr_notice("Write of %d bytes at 0x%08x failed. returned %d, retlen %zd\n",
+ rawlen, phys_ofs, ret, retlen);
+ if (retlen) {
+ jffs2_add_physical_node_ref(c, phys_ofs | REF_OBSOLETE, rawlen, NULL);
+ } else {
+ pr_notice("Not marking the space at 0x%08x as dirty because the flash driver returned retlen zero\n",
+ phys_ofs);
+ }
+ if (!retried) {
+ /* Try to reallocate space and retry */
+ uint32_t dummy;
+ struct jffs2_eraseblock *jeb = &c->blocks[phys_ofs / c->sector_size];
+
+ retried = 1;
+
+ jffs2_dbg(1, "Retrying failed write of REF_PRISTINE node.\n");
+
+ jffs2_dbg_acct_sanity_check(c,jeb);
+ jffs2_dbg_acct_paranoia_check(c, jeb);
+
+ ret = jffs2_reserve_space_gc(c, rawlen, &dummy, rawlen);
+ /* this is not the exact summary size of it,
+ it is only an upper estimation */
+
+ if (!ret) {
+ jffs2_dbg(1, "Allocated space at 0x%08x to retry failed write.\n",
+ phys_ofs);
+
+ jffs2_dbg_acct_sanity_check(c,jeb);
+ jffs2_dbg_acct_paranoia_check(c, jeb);
+
+ goto retry;
+ }
+ jffs2_dbg(1, "Failed to allocate space to retry failed write: %d!\n",
+ ret);
+ }
+
+ if (!ret)
+ ret = -EIO;
+ goto out_node;
+ }
+ jffs2_add_physical_node_ref(c, phys_ofs | REF_PRISTINE, rawlen, ic);
+
+ jffs2_mark_node_obsolete(c, raw);
+ jffs2_dbg(1, "WHEEE! GC REF_PRISTINE node at 0x%08x succeeded\n",
+ ref_offset(raw));
+
+ out_node:
+ kfree(node);
+ return ret;
+ bail:
+ ret = -EBADFD;
+ goto out_node;
+}
+
+static int jffs2_garbage_collect_metadata(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+ struct jffs2_inode_info *f, struct jffs2_full_dnode *fn)
+{
+ struct jffs2_full_dnode *new_fn;
+ struct jffs2_raw_inode ri;
+ struct jffs2_node_frag *last_frag;
+ union jffs2_device_node dev;
+ char *mdata = NULL;
+ int mdatalen = 0;
+ uint32_t alloclen, ilen;
+ int ret;
+
+ if (S_ISBLK(JFFS2_F_I_MODE(f)) ||
+ S_ISCHR(JFFS2_F_I_MODE(f)) ) {
+ /* For these, we don't actually need to read the old node */
+ mdatalen = jffs2_encode_dev(&dev, JFFS2_F_I_RDEV(f));
+ mdata = (char *)&dev;
+ jffs2_dbg(1, "%s(): Writing %d bytes of kdev_t\n",
+ __func__, mdatalen);
+ } else if (S_ISLNK(JFFS2_F_I_MODE(f))) {
+ mdatalen = fn->size;
+ mdata = kmalloc(fn->size, GFP_KERNEL);
+ if (!mdata) {
+ pr_warn("kmalloc of mdata failed in jffs2_garbage_collect_metadata()\n");
+ return -ENOMEM;
+ }
+ ret = jffs2_read_dnode(c, f, fn, mdata, 0, mdatalen);
+ if (ret) {
+ pr_warn("read of old metadata failed in jffs2_garbage_collect_metadata(): %d\n",
+ ret);
+ kfree(mdata);
+ return ret;
+ }
+ jffs2_dbg(1, "%s(): Writing %d bites of symlink target\n",
+ __func__, mdatalen);
+
+ }
+
+ ret = jffs2_reserve_space_gc(c, sizeof(ri) + mdatalen, &alloclen,
+ JFFS2_SUMMARY_INODE_SIZE);
+ if (ret) {
+ pr_warn("jffs2_reserve_space_gc of %zd bytes for garbage_collect_metadata failed: %d\n",
+ sizeof(ri) + mdatalen, ret);
+ goto out;
+ }
+
+ last_frag = frag_last(&f->fragtree);
+ if (last_frag)
+ /* Fetch the inode length from the fragtree rather then
+ * from i_size since i_size may have not been updated yet */
+ ilen = last_frag->ofs + last_frag->size;
+ else
+ ilen = JFFS2_F_I_SIZE(f);
+
+ memset(&ri, 0, sizeof(ri));
+ ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
+ ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
+ ri.totlen = cpu_to_je32(sizeof(ri) + mdatalen);
+ ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));
+
+ ri.ino = cpu_to_je32(f->inocache->ino);
+ ri.version = cpu_to_je32(++f->highest_version);
+ ri.mode = cpu_to_jemode(JFFS2_F_I_MODE(f));
+ ri.uid = cpu_to_je16(JFFS2_F_I_UID(f));
+ ri.gid = cpu_to_je16(JFFS2_F_I_GID(f));
+ ri.isize = cpu_to_je32(ilen);
+ ri.atime = cpu_to_je32(JFFS2_F_I_ATIME(f));
+ ri.ctime = cpu_to_je32(JFFS2_F_I_CTIME(f));
+ ri.mtime = cpu_to_je32(JFFS2_F_I_MTIME(f));
+ ri.offset = cpu_to_je32(0);
+ ri.csize = cpu_to_je32(mdatalen);
+ ri.dsize = cpu_to_je32(mdatalen);
+ ri.compr = JFFS2_COMPR_NONE;
+ ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
+ ri.data_crc = cpu_to_je32(crc32(0, mdata, mdatalen));
+
+ new_fn = jffs2_write_dnode(c, f, &ri, mdata, mdatalen, ALLOC_GC);
+
+ if (IS_ERR(new_fn)) {
+ pr_warn("Error writing new dnode: %ld\n", PTR_ERR(new_fn));
+ ret = PTR_ERR(new_fn);
+ goto out;
+ }
+ jffs2_mark_node_obsolete(c, fn->raw);
+ jffs2_free_full_dnode(fn);
+ f->metadata = new_fn;
+ out:
+ if (S_ISLNK(JFFS2_F_I_MODE(f)))
+ kfree(mdata);
+ return ret;
+}
+
+static int jffs2_garbage_collect_dirent(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+ struct jffs2_inode_info *f, struct jffs2_full_dirent *fd)
+{
+ struct jffs2_full_dirent *new_fd;
+ struct jffs2_raw_dirent rd;
+ uint32_t alloclen;
+ int ret;
+
+ rd.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
+ rd.nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
+ rd.nsize = strlen(fd->name);
+ rd.totlen = cpu_to_je32(sizeof(rd) + rd.nsize);
+ rd.hdr_crc = cpu_to_je32(crc32(0, &rd, sizeof(struct jffs2_unknown_node)-4));
+
+ rd.pino = cpu_to_je32(f->inocache->ino);
+ rd.version = cpu_to_je32(++f->highest_version);
+ rd.ino = cpu_to_je32(fd->ino);
+ /* If the times on this inode were set by explicit utime() they can be different,
+ so refrain from splatting them. */
+ if (JFFS2_F_I_MTIME(f) == JFFS2_F_I_CTIME(f))
+ rd.mctime = cpu_to_je32(JFFS2_F_I_MTIME(f));
+ else
+ rd.mctime = cpu_to_je32(0);
+ rd.type = fd->type;
+ rd.node_crc = cpu_to_je32(crc32(0, &rd, sizeof(rd)-8));
+ rd.name_crc = cpu_to_je32(crc32(0, fd->name, rd.nsize));
+
+ ret = jffs2_reserve_space_gc(c, sizeof(rd)+rd.nsize, &alloclen,
+ JFFS2_SUMMARY_DIRENT_SIZE(rd.nsize));
+ if (ret) {
+ pr_warn("jffs2_reserve_space_gc of %zd bytes for garbage_collect_dirent failed: %d\n",
+ sizeof(rd)+rd.nsize, ret);
+ return ret;
+ }
+ new_fd = jffs2_write_dirent(c, f, &rd, fd->name, rd.nsize, ALLOC_GC);
+
+ if (IS_ERR(new_fd)) {
+ pr_warn("jffs2_write_dirent in garbage_collect_dirent failed: %ld\n",
+ PTR_ERR(new_fd));
+ return PTR_ERR(new_fd);
+ }
+ jffs2_add_fd_to_list(c, new_fd, &f->dents);
+ return 0;
+}
+
+static int jffs2_garbage_collect_deletion_dirent(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+ struct jffs2_inode_info *f, struct jffs2_full_dirent *fd)
+{
+ struct jffs2_full_dirent **fdp = &f->dents;
+ int found = 0;
+
+ /* On a medium where we can't actually mark nodes obsolete
+ pernamently, such as NAND flash, we need to work out
+ whether this deletion dirent is still needed to actively
+ delete a 'real' dirent with the same name that's still
+ somewhere else on the flash. */
+ if (!jffs2_can_mark_obsolete(c)) {
+ struct jffs2_raw_dirent *rd;
+ struct jffs2_raw_node_ref *raw;
+ int ret;
+ size_t retlen;
+ int name_len = strlen(fd->name);
+ uint32_t name_crc = crc32(0, fd->name, name_len);
+ uint32_t rawlen = ref_totlen(c, jeb, fd->raw);
+
+ rd = kmalloc(rawlen, GFP_KERNEL);
+ if (!rd)
+ return -ENOMEM;
+
+ /* Prevent the erase code from nicking the obsolete node refs while
+ we're looking at them. I really don't like this extra lock but
+ can't see any alternative. Suggestions on a postcard to... */
+ mutex_lock(&c->erase_free_sem);
+
+ for (raw = f->inocache->nodes; raw != (void *)f->inocache; raw = raw->next_in_ino) {
+
+ cond_resched();
+
+ /* We only care about obsolete ones */
+ if (!(ref_obsolete(raw)))
+ continue;
+
+ /* Any dirent with the same name is going to have the same length... */
+ if (ref_totlen(c, NULL, raw) != rawlen)
+ continue;
+
+ /* Doesn't matter if there's one in the same erase block. We're going to
+ delete it too at the same time. */
+ if (SECTOR_ADDR(raw->flash_offset) == SECTOR_ADDR(fd->raw->flash_offset))
+ continue;
+
+ jffs2_dbg(1, "Check potential deletion dirent at %08x\n",
+ ref_offset(raw));
+
+ /* This is an obsolete node belonging to the same directory, and it's of the right
+ length. We need to take a closer look...*/
+ ret = jffs2_flash_read(c, ref_offset(raw), rawlen, &retlen, (char *)rd);
+ if (ret) {
+ pr_warn("%s(): Read error (%d) reading obsolete node at %08x\n",
+ __func__, ret, ref_offset(raw));
+ /* If we can't read it, we don't need to continue to obsolete it. Continue */
+ continue;
+ }
+ if (retlen != rawlen) {
+ pr_warn("%s(): Short read (%zd not %u) reading header from obsolete node at %08x\n",
+ __func__, retlen, rawlen,
+ ref_offset(raw));
+ continue;
+ }
+
+ if (je16_to_cpu(rd->nodetype) != JFFS2_NODETYPE_DIRENT)
+ continue;
+
+ /* If the name CRC doesn't match, skip */
+ if (je32_to_cpu(rd->name_crc) != name_crc)
+ continue;
+
+ /* If the name length doesn't match, or it's another deletion dirent, skip */
+ if (rd->nsize != name_len || !je32_to_cpu(rd->ino))
+ continue;
+
+ /* OK, check the actual name now */
+ if (memcmp(rd->name, fd->name, name_len))
+ continue;
+
+ /* OK. The name really does match. There really is still an older node on
+ the flash which our deletion dirent obsoletes. So we have to write out
+ a new deletion dirent to replace it */
+ mutex_unlock(&c->erase_free_sem);
+
+ jffs2_dbg(1, "Deletion dirent at %08x still obsoletes real dirent \"%s\" at %08x for ino #%u\n",
+ ref_offset(fd->raw), fd->name,
+ ref_offset(raw), je32_to_cpu(rd->ino));
+ kfree(rd);
+
+ return jffs2_garbage_collect_dirent(c, jeb, f, fd);
+ }
+
+ mutex_unlock(&c->erase_free_sem);
+ kfree(rd);
+ }
+
+ /* FIXME: If we're deleting a dirent which contains the current mtime and ctime,
+ we should update the metadata node with those times accordingly */
+
+ /* No need for it any more. Just mark it obsolete and remove it from the list */
+ while (*fdp) {
+ if ((*fdp) == fd) {
+ found = 1;
+ *fdp = fd->next;
+ break;
+ }
+ fdp = &(*fdp)->next;
+ }
+ if (!found) {
+ pr_warn("Deletion dirent \"%s\" not found in list for ino #%u\n",
+ fd->name, f->inocache->ino);
+ }
+ jffs2_mark_node_obsolete(c, fd->raw);
+ jffs2_free_full_dirent(fd);
+ return 0;
+}
+
+static int jffs2_garbage_collect_hole(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+ struct jffs2_inode_info *f, struct jffs2_full_dnode *fn,
+ uint32_t start, uint32_t end)
+{
+ struct jffs2_raw_inode ri;
+ struct jffs2_node_frag *frag;
+ struct jffs2_full_dnode *new_fn;
+ uint32_t alloclen, ilen;
+ int ret;
+
+ jffs2_dbg(1, "Writing replacement hole node for ino #%u from offset 0x%x to 0x%x\n",
+ f->inocache->ino, start, end);
+
+ memset(&ri, 0, sizeof(ri));
+
+ if(fn->frags > 1) {
+ size_t readlen;
+ uint32_t crc;
+ /* It's partially obsoleted by a later write. So we have to
+ write it out again with the _same_ version as before */
+ ret = jffs2_flash_read(c, ref_offset(fn->raw), sizeof(ri), &readlen, (char *)&ri);
+ if (readlen != sizeof(ri) || ret) {
+ pr_warn("Node read failed in jffs2_garbage_collect_hole. Ret %d, retlen %zd. Data will be lost by writing new hole node\n",
+ ret, readlen);
+ goto fill;
+ }
+ if (je16_to_cpu(ri.nodetype) != JFFS2_NODETYPE_INODE) {
+ pr_warn("%s(): Node at 0x%08x had node type 0x%04x instead of JFFS2_NODETYPE_INODE(0x%04x)\n",
+ __func__, ref_offset(fn->raw),
+ je16_to_cpu(ri.nodetype), JFFS2_NODETYPE_INODE);
+ return -EIO;
+ }
+ if (je32_to_cpu(ri.totlen) != sizeof(ri)) {
+ pr_warn("%s(): Node at 0x%08x had totlen 0x%x instead of expected 0x%zx\n",
+ __func__, ref_offset(fn->raw),
+ je32_to_cpu(ri.totlen), sizeof(ri));
+ return -EIO;
+ }
+ crc = crc32(0, &ri, sizeof(ri)-8);
+ if (crc != je32_to_cpu(ri.node_crc)) {
+ pr_warn("%s: Node at 0x%08x had CRC 0x%08x which doesn't match calculated CRC 0x%08x\n",
+ __func__, ref_offset(fn->raw),
+ je32_to_cpu(ri.node_crc), crc);
+ /* FIXME: We could possibly deal with this by writing new holes for each frag */
+ pr_warn("Data in the range 0x%08x to 0x%08x of inode #%u will be lost\n",
+ start, end, f->inocache->ino);
+ goto fill;
+ }
+ if (ri.compr != JFFS2_COMPR_ZERO) {
+ pr_warn("%s(): Node 0x%08x wasn't a hole node!\n",
+ __func__, ref_offset(fn->raw));
+ pr_warn("Data in the range 0x%08x to 0x%08x of inode #%u will be lost\n",
+ start, end, f->inocache->ino);
+ goto fill;
+ }
+ } else {
+ fill:
+ ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
+ ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
+ ri.totlen = cpu_to_je32(sizeof(ri));
+ ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));
+
+ ri.ino = cpu_to_je32(f->inocache->ino);
+ ri.version = cpu_to_je32(++f->highest_version);
+ ri.offset = cpu_to_je32(start);
+ ri.dsize = cpu_to_je32(end - start);
+ ri.csize = cpu_to_je32(0);
+ ri.compr = JFFS2_COMPR_ZERO;
+ }
+
+ frag = frag_last(&f->fragtree);
+ if (frag)
+ /* Fetch the inode length from the fragtree rather then
+ * from i_size since i_size may have not been updated yet */
+ ilen = frag->ofs + frag->size;
+ else
+ ilen = JFFS2_F_I_SIZE(f);
+
+ ri.mode = cpu_to_jemode(JFFS2_F_I_MODE(f));
+ ri.uid = cpu_to_je16(JFFS2_F_I_UID(f));
+ ri.gid = cpu_to_je16(JFFS2_F_I_GID(f));
+ ri.isize = cpu_to_je32(ilen);
+ ri.atime = cpu_to_je32(JFFS2_F_I_ATIME(f));
+ ri.ctime = cpu_to_je32(JFFS2_F_I_CTIME(f));
+ ri.mtime = cpu_to_je32(JFFS2_F_I_MTIME(f));
+ ri.data_crc = cpu_to_je32(0);
+ ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
+
+ ret = jffs2_reserve_space_gc(c, sizeof(ri), &alloclen,
+ JFFS2_SUMMARY_INODE_SIZE);
+ if (ret) {
+ pr_warn("jffs2_reserve_space_gc of %zd bytes for garbage_collect_hole failed: %d\n",
+ sizeof(ri), ret);
+ return ret;
+ }
+ new_fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_GC);
+
+ if (IS_ERR(new_fn)) {
+ pr_warn("Error writing new hole node: %ld\n", PTR_ERR(new_fn));
+ return PTR_ERR(new_fn);
+ }
+ if (je32_to_cpu(ri.version) == f->highest_version) {
+ jffs2_add_full_dnode_to_inode(c, f, new_fn);
+ if (f->metadata) {
+ jffs2_mark_node_obsolete(c, f->metadata->raw);
+ jffs2_free_full_dnode(f->metadata);
+ f->metadata = NULL;
+ }
+ return 0;
+ }
+
+ /*
+ * We should only get here in the case where the node we are
+ * replacing had more than one frag, so we kept the same version
+ * number as before. (Except in case of error -- see 'goto fill;'
+ * above.)
+ */
+ D1(if(unlikely(fn->frags <= 1)) {
+ pr_warn("%s(): Replacing fn with %d frag(s) but new ver %d != highest_version %d of ino #%d\n",
+ __func__, fn->frags, je32_to_cpu(ri.version),
+ f->highest_version, je32_to_cpu(ri.ino));
+ });
+
+ /* This is a partially-overlapped hole node. Mark it REF_NORMAL not REF_PRISTINE */
+ mark_ref_normal(new_fn->raw);
+
+ for (frag = jffs2_lookup_node_frag(&f->fragtree, fn->ofs);
+ frag; frag = frag_next(frag)) {
+ if (frag->ofs > fn->size + fn->ofs)
+ break;
+ if (frag->node == fn) {
+ frag->node = new_fn;
+ new_fn->frags++;
+ fn->frags--;
+ }
+ }
+ if (fn->frags) {
+ pr_warn("%s(): Old node still has frags!\n", __func__);
+ BUG();
+ }
+ if (!new_fn->frags) {
+ pr_warn("%s(): New node has no frags!\n", __func__);
+ BUG();
+ }
+
+ jffs2_mark_node_obsolete(c, fn->raw);
+ jffs2_free_full_dnode(fn);
+
+ return 0;
+}
+
+static int jffs2_garbage_collect_dnode(struct jffs2_sb_info *c, struct jffs2_eraseblock *orig_jeb,
+ struct jffs2_inode_info *f, struct jffs2_full_dnode *fn,
+ uint32_t start, uint32_t end)
+{
+ struct jffs2_full_dnode *new_fn;
+ struct jffs2_raw_inode ri;
+ uint32_t alloclen, offset, orig_end, orig_start;
+ int ret = 0;
+ unsigned char *comprbuf = NULL, *writebuf;
+ unsigned long pg;
+ unsigned char *pg_ptr;
+
+ memset(&ri, 0, sizeof(ri));
+
+ jffs2_dbg(1, "Writing replacement dnode for ino #%u from offset 0x%x to 0x%x\n",
+ f->inocache->ino, start, end);
+
+ orig_end = end;
+ orig_start = start;
+
+ if (c->nr_free_blocks + c->nr_erasing_blocks > c->resv_blocks_gcmerge) {
+ /* Attempt to do some merging. But only expand to cover logically
+ adjacent frags if the block containing them is already considered
+ to be dirty. Otherwise we end up with GC just going round in
+ circles dirtying the nodes it already wrote out, especially
+ on NAND where we have small eraseblocks and hence a much higher
+ chance of nodes having to be split to cross boundaries. */
+
+ struct jffs2_node_frag *frag;
+ uint32_t min, max;
+
+ min = start & ~(PAGE_CACHE_SIZE-1);
+ max = min + PAGE_CACHE_SIZE;
+
+ frag = jffs2_lookup_node_frag(&f->fragtree, start);
+
+ /* BUG_ON(!frag) but that'll happen anyway... */
+
+ BUG_ON(frag->ofs != start);
+
+ /* First grow down... */
+ while((frag = frag_prev(frag)) && frag->ofs >= min) {
+
+ /* If the previous frag doesn't even reach the beginning, there's
+ excessive fragmentation. Just merge. */
+ if (frag->ofs > min) {
+ jffs2_dbg(1, "Expanding down to cover partial frag (0x%x-0x%x)\n",
+ frag->ofs, frag->ofs+frag->size);
+ start = frag->ofs;
+ continue;
+ }
+ /* OK. This frag holds the first byte of the page. */
+ if (!frag->node || !frag->node->raw) {
+ jffs2_dbg(1, "First frag in page is hole (0x%x-0x%x). Not expanding down.\n",
+ frag->ofs, frag->ofs+frag->size);
+ break;
+ } else {
+
+ /* OK, it's a frag which extends to the beginning of the page. Does it live
+ in a block which is still considered clean? If so, don't obsolete it.
+ If not, cover it anyway. */
+
+ struct jffs2_raw_node_ref *raw = frag->node->raw;
+ struct jffs2_eraseblock *jeb;
+
+ jeb = &c->blocks[raw->flash_offset / c->sector_size];
+
+ if (jeb == c->gcblock) {
+ jffs2_dbg(1, "Expanding down to cover frag (0x%x-0x%x) in gcblock at %08x\n",
+ frag->ofs,
+ frag->ofs + frag->size,
+ ref_offset(raw));
+ start = frag->ofs;
+ break;
+ }
+ if (!ISDIRTY(jeb->dirty_size + jeb->wasted_size)) {
+ jffs2_dbg(1, "Not expanding down to cover frag (0x%x-0x%x) in clean block %08x\n",
+ frag->ofs,
+ frag->ofs + frag->size,
+ jeb->offset);
+ break;
+ }
+
+ jffs2_dbg(1, "Expanding down to cover frag (0x%x-0x%x) in dirty block %08x\n",
+ frag->ofs,
+ frag->ofs + frag->size,
+ jeb->offset);
+ start = frag->ofs;
+ break;
+ }
+ }
+
+ /* ... then up */
+
+ /* Find last frag which is actually part of the node we're to GC. */
+ frag = jffs2_lookup_node_frag(&f->fragtree, end-1);
+
+ while((frag = frag_next(frag)) && frag->ofs+frag->size <= max) {
+
+ /* If the previous frag doesn't even reach the beginning, there's lots
+ of fragmentation. Just merge. */
+ if (frag->ofs+frag->size < max) {
+ jffs2_dbg(1, "Expanding up to cover partial frag (0x%x-0x%x)\n",
+ frag->ofs, frag->ofs+frag->size);
+ end = frag->ofs + frag->size;
+ continue;
+ }
+
+ if (!frag->node || !frag->node->raw) {
+ jffs2_dbg(1, "Last frag in page is hole (0x%x-0x%x). Not expanding up.\n",
+ frag->ofs, frag->ofs+frag->size);
+ break;
+ } else {
+
+ /* OK, it's a frag which extends to the beginning of the page. Does it live
+ in a block which is still considered clean? If so, don't obsolete it.
+ If not, cover it anyway. */
+
+ struct jffs2_raw_node_ref *raw = frag->node->raw;
+ struct jffs2_eraseblock *jeb;
+
+ jeb = &c->blocks[raw->flash_offset / c->sector_size];
+
+ if (jeb == c->gcblock) {
+ jffs2_dbg(1, "Expanding up to cover frag (0x%x-0x%x) in gcblock at %08x\n",
+ frag->ofs,
+ frag->ofs + frag->size,
+ ref_offset(raw));
+ end = frag->ofs + frag->size;
+ break;
+ }
+ if (!ISDIRTY(jeb->dirty_size + jeb->wasted_size)) {
+ jffs2_dbg(1, "Not expanding up to cover frag (0x%x-0x%x) in clean block %08x\n",
+ frag->ofs,
+ frag->ofs + frag->size,
+ jeb->offset);
+ break;
+ }
+
+ jffs2_dbg(1, "Expanding up to cover frag (0x%x-0x%x) in dirty block %08x\n",
+ frag->ofs,
+ frag->ofs + frag->size,
+ jeb->offset);
+ end = frag->ofs + frag->size;
+ break;
+ }
+ }
+ jffs2_dbg(1, "Expanded dnode to write from (0x%x-0x%x) to (0x%x-0x%x)\n",
+ orig_start, orig_end, start, end);
+
+ D1(BUG_ON(end > frag_last(&f->fragtree)->ofs + frag_last(&f->fragtree)->size));
+ BUG_ON(end < orig_end);
+ BUG_ON(start > orig_start);
+ }
+
+ /* First, use readpage() to read the appropriate page into the page cache */
+ /* Q: What happens if we actually try to GC the _same_ page for which commit_write()
+ * triggered garbage collection in the first place?
+ * A: I _think_ it's OK. read_cache_page shouldn't deadlock, we'll write out the
+ * page OK. We'll actually write it out again in commit_write, which is a little
+ * suboptimal, but at least we're correct.
+ */
+ pg_ptr = jffs2_gc_fetch_page(c, f, start, &pg);
+
+ if (IS_ERR(pg_ptr)) {
+ pr_warn("read_cache_page() returned error: %ld\n",
+ PTR_ERR(pg_ptr));
+ return PTR_ERR(pg_ptr);
+ }
+
+ offset = start;
+ while(offset < orig_end) {
+ uint32_t datalen;
+ uint32_t cdatalen;
+ uint16_t comprtype = JFFS2_COMPR_NONE;
+
+ ret = jffs2_reserve_space_gc(c, sizeof(ri) + JFFS2_MIN_DATA_LEN,
+ &alloclen, JFFS2_SUMMARY_INODE_SIZE);
+
+ if (ret) {
+ pr_warn("jffs2_reserve_space_gc of %zd bytes for garbage_collect_dnode failed: %d\n",
+ sizeof(ri) + JFFS2_MIN_DATA_LEN, ret);
+ break;
+ }
+ cdatalen = min_t(uint32_t, alloclen - sizeof(ri), end - offset);
+ datalen = end - offset;
+
+ writebuf = pg_ptr + (offset & (PAGE_CACHE_SIZE -1));
+
+ comprtype = jffs2_compress(c, f, writebuf, &comprbuf, &datalen, &cdatalen);
+
+ ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
+ ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
+ ri.totlen = cpu_to_je32(sizeof(ri) + cdatalen);
+ ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));
+
+ ri.ino = cpu_to_je32(f->inocache->ino);
+ ri.version = cpu_to_je32(++f->highest_version);
+ ri.mode = cpu_to_jemode(JFFS2_F_I_MODE(f));
+ ri.uid = cpu_to_je16(JFFS2_F_I_UID(f));
+ ri.gid = cpu_to_je16(JFFS2_F_I_GID(f));
+ ri.isize = cpu_to_je32(JFFS2_F_I_SIZE(f));
+ ri.atime = cpu_to_je32(JFFS2_F_I_ATIME(f));
+ ri.ctime = cpu_to_je32(JFFS2_F_I_CTIME(f));
+ ri.mtime = cpu_to_je32(JFFS2_F_I_MTIME(f));
+ ri.offset = cpu_to_je32(offset);
+ ri.csize = cpu_to_je32(cdatalen);
+ ri.dsize = cpu_to_je32(datalen);
+ ri.compr = comprtype & 0xff;
+ ri.usercompr = (comprtype >> 8) & 0xff;
+ ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
+ ri.data_crc = cpu_to_je32(crc32(0, comprbuf, cdatalen));
+
+ new_fn = jffs2_write_dnode(c, f, &ri, comprbuf, cdatalen, ALLOC_GC);
+
+ jffs2_free_comprbuf(comprbuf, writebuf);
+
+ if (IS_ERR(new_fn)) {
+ pr_warn("Error writing new dnode: %ld\n",
+ PTR_ERR(new_fn));
+ ret = PTR_ERR(new_fn);
+ break;
+ }
+ ret = jffs2_add_full_dnode_to_inode(c, f, new_fn);
+ offset += datalen;
+ if (f->metadata) {
+ jffs2_mark_node_obsolete(c, f->metadata->raw);
+ jffs2_free_full_dnode(f->metadata);
+ f->metadata = NULL;
+ }
+ }
+
+ jffs2_gc_release_page(c, pg_ptr, &pg);
+ return ret;
+}
Code Review / kvmfornfv.git / blobdiff