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gc.c
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gc.c
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/*
* 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 (;;) {
/* We can't start doing GC until we've finished checking
the node CRCs etc. */
int bucket, want_ino;
spin_lock(&c->erase_completion_lock);
if (!c->unchecked_size)
break;
spin_unlock(&c->erase_completion_lock);
if (!xattr)
xattr = jffs2_verify_xattr(c);
spin_lock(&c->inocache_lock);
/* Instead of doing the inodes in numeric order, doing a lookup
* in the hash for each possible number, just walk the hash
* buckets of *existing* inodes. This means that we process
* them out-of-order, but it can be a lot faster if there's
* a sparse inode# space. Which there often is. */
want_ino = c->check_ino;
for (bucket = c->check_ino % c->inocache_hashsize ; bucket < c->inocache_hashsize; bucket++) {
for (ic = c->inocache_list[bucket]; ic; ic = ic->next) {
if (ic->ino < want_ino)
continue;
if (ic->state != INO_STATE_CHECKEDABSENT &&
ic->state != INO_STATE_PRESENT)
goto got_next; /* with inocache_lock held */
jffs2_dbg(1, "Skipping ino #%u already checked\n",
ic->ino);
}
want_ino = 0;
}
/* Point c->check_ino past the end of the last bucket. */
c->check_ino = ((c->highest_ino + c->inocache_hashsize + 1) &
~c->inocache_hashsize) - 1;
spin_unlock(&c->inocache_lock);
pr_crit("Checked all inodes but still 0x%x bytes of unchecked space?\n",
c->unchecked_size);
jffs2_dbg_dump_block_lists_nolock(c);
mutex_unlock(&c->alloc_sem);
return -ENOSPC;
got_next:
/* For next time round the loop, we want c->checked_ino to indicate
* the *next* one we want to check. And since we're walking the
* buckets rather than doing it sequentially, it's: */
c->check_ino = ic->ino + c->inocache_hashsize;
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:
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->check_ino = ic->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_SHIFT) < ((end-1) >> PAGE_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;