Commit 3af91a12 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6 

* 'linux-next' of git://git.infradead.org/ubifs-2.6:
  UBIFS: fix-up free space earlier
  UBIFS: intialize LPT earlier
  UBIFS: assert no fixup when writing a node
  UBIFS: fix clean znode counter corruption in error cases
  UBIFS: fix memory leak on error path
  UBIFS: fix shrinker object count reports
  UBIFS: fix recovery broken by the previous recovery fix
  UBIFS: amend ubifs_recover_leb interface
  UBIFS: introduce a "grouped" journal head flag
  UBIFS: supress false error messages
parents 9a44fde3 09801194

fs/ubifs/io.c

+2 −0
Original line number Diff line number Diff line
@@ -581,6 +581,7 @@ int ubifs_wbuf_write_nolock(struct ubifs_wbuf *wbuf, void *buf, int len) 
	ubifs_assert(wbuf->size % c->min_io_size == 0);

	ubifs_assert(mutex_is_locked(&wbuf->io_mutex));

	ubifs_assert(!c->ro_media && !c->ro_mount);

	ubifs_assert(!c->space_fixup);

	if (c->leb_size - wbuf->offs >= c->max_write_size)

		ubifs_assert(!((wbuf->offs + wbuf->size) % c->max_write_size));
@@ -759,6 +760,7 @@ int ubifs_write_node(struct ubifs_info *c, void *buf, int len, int lnum, 
	ubifs_assert(lnum >= 0 && lnum < c->leb_cnt && offs >= 0);

	ubifs_assert(offs % c->min_io_size == 0 && offs < c->leb_size);

	ubifs_assert(!c->ro_media && !c->ro_mount);

	ubifs_assert(!c->space_fixup);



	if (c->ro_error)

		return -EROFS;

fs/ubifs/journal.c

+1 −0
Original line number Diff line number Diff line
@@ -669,6 +669,7 @@ out_free: 


out_release:

	release_head(c, BASEHD);

	kfree(dent);

out_ro:

	ubifs_ro_mode(c, err);

	if (last_reference)

fs/ubifs/orphan.c

+1 −1
Original line number Diff line number Diff line
@@ -674,7 +674,7 @@ static int kill_orphans(struct ubifs_info *c) 
		if (IS_ERR(sleb)) {

			if (PTR_ERR(sleb) == -EUCLEAN)

				sleb = ubifs_recover_leb(c, lnum, 0,

							 c->sbuf, 0);

							 c->sbuf, -1);

			if (IS_ERR(sleb)) {

				err = PTR_ERR(sleb);

				break;

fs/ubifs/recovery.c

+94 −70
Original line number Diff line number Diff line
@@ -564,19 +564,15 @@ static int fix_unclean_leb(struct ubifs_info *c, struct ubifs_scan_leb *sleb, 
}



/**

 * drop_last_node - drop the last node or group of nodes.

 * drop_last_group - drop the last group of nodes.

 * @sleb: scanned LEB information

 * @offs: offset of dropped nodes is returned here

 * @grouped: non-zero if whole group of nodes have to be dropped

 *

 * This is a helper function for 'ubifs_recover_leb()' which drops the last

 * node of the scanned LEB or the last group of nodes if @grouped is not zero.

 * This function returns %1 if a node was dropped and %0 otherwise.

 * group of nodes of the scanned LEB.

 */

static int drop_last_node(struct ubifs_scan_leb *sleb, int *offs, int grouped)

static void drop_last_group(struct ubifs_scan_leb *sleb, int *offs)

{

	int dropped = 0;



	while (!list_empty(&sleb->nodes)) {

		struct ubifs_scan_node *snod;

		struct ubifs_ch *ch;
@@ -585,17 +581,40 @@ static int drop_last_node(struct ubifs_scan_leb *sleb, int *offs, int grouped) 
				  list);

		ch = snod->node;

		if (ch->group_type != UBIFS_IN_NODE_GROUP)

			return dropped;

		dbg_rcvry("dropping node at %d:%d", sleb->lnum, snod->offs);

			break;



		dbg_rcvry("dropping grouped node at %d:%d",

			  sleb->lnum, snod->offs);

		*offs = snod->offs;

		list_del(&snod->list);

		kfree(snod);

		sleb->nodes_cnt -= 1;

	}

}



/**

 * drop_last_node - drop the last node.

 * @sleb: scanned LEB information

 * @offs: offset of dropped nodes is returned here

 * @grouped: non-zero if whole group of nodes have to be dropped

 *

 * This is a helper function for 'ubifs_recover_leb()' which drops the last

 * node of the scanned LEB.

 */

static void drop_last_node(struct ubifs_scan_leb *sleb, int *offs)

{

	struct ubifs_scan_node *snod;



	if (!list_empty(&sleb->nodes)) {

		snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node,

				  list);



		dbg_rcvry("dropping last node at %d:%d", sleb->lnum, snod->offs);

		*offs = snod->offs;

		list_del(&snod->list);

		kfree(snod);

		sleb->nodes_cnt -= 1;

		dropped = 1;

		if (!grouped)

			break;

	}

	return dropped;

}



/**
@@ -604,7 +623,8 @@ static int drop_last_node(struct ubifs_scan_leb *sleb, int *offs, int grouped) 
 * @lnum: LEB number

 * @offs: offset

 * @sbuf: LEB-sized buffer to use

 * @grouped: nodes may be grouped for recovery

 * @jhead: journal head number this LEB belongs to (%-1 if the LEB does not

 *         belong to any journal head)

 *

 * This function does a scan of a LEB, but caters for errors that might have

 * been caused by the unclean unmount from which we are attempting to recover.
@@ -612,13 +632,14 @@ static int drop_last_node(struct ubifs_scan_leb *sleb, int *offs, int grouped) 
 * found, and a negative error code in case of failure.

 */

struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum,

					 int offs, void *sbuf, int grouped)

					 int offs, void *sbuf, int jhead)

{

	int ret = 0, err, len = c->leb_size - offs, start = offs, min_io_unit;

	int grouped = jhead == -1 ? 0 : c->jheads[jhead].grouped;

	struct ubifs_scan_leb *sleb;

	void *buf = sbuf + offs;



	dbg_rcvry("%d:%d", lnum, offs);

	dbg_rcvry("%d:%d, jhead %d, grouped %d", lnum, offs, jhead, grouped);



	sleb = ubifs_start_scan(c, lnum, offs, sbuf);

	if (IS_ERR(sleb))
@@ -635,7 +656,7 @@ struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum, 
		 * Scan quietly until there is an error from which we cannot

		 * recover

		 */

		ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 0);

		ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1);

		if (ret == SCANNED_A_NODE) {

			/* A valid node, and not a padding node */

			struct ubifs_ch *ch = buf;
@@ -695,59 +716,62 @@ struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum, 
		 * If nodes are grouped, always drop the incomplete group at

		 * the end.

		 */

		drop_last_node(sleb, &offs, 1);

		drop_last_group(sleb, &offs);



	if (jhead == GCHD) {

		/*

	 * While we are in the middle of the same min. I/O unit keep dropping

	 * nodes. So basically, what we want is to make sure that the last min.

	 * I/O unit where we saw the corruption is dropped completely with all

	 * the uncorrupted node which may possibly sit there.

		 * If this LEB belongs to the GC head then while we are in the

		 * middle of the same min. I/O unit keep dropping nodes. So

		 * basically, what we want is to make sure that the last min.

		 * I/O unit where we saw the corruption is dropped completely

		 * with all the uncorrupted nodes which may possibly sit there.

		 *

	 * In other words, let's name the min. I/O unit where the corruption

	 * starts B, and the previous min. I/O unit A. The below code tries to

	 * deal with a situation when half of B contains valid nodes or the end

	 * of a valid node, and the second half of B contains corrupted data or

	 * garbage. This means that UBIFS had been writing to B just before the

	 * power cut happened. I do not know how realistic is this scenario

	 * that half of the min. I/O unit had been written successfully and the

	 * other half not, but this is possible in our 'failure mode emulation'

	 * infrastructure at least.

		 * In other words, let's name the min. I/O unit where the

		 * corruption starts B, and the previous min. I/O unit A. The

		 * below code tries to deal with a situation when half of B

		 * contains valid nodes or the end of a valid node, and the

		 * second half of B contains corrupted data or garbage. This

		 * means that UBIFS had been writing to B just before the power

		 * cut happened. I do not know how realistic is this scenario

		 * that half of the min. I/O unit had been written successfully

		 * and the other half not, but this is possible in our 'failure

		 * mode emulation' infrastructure at least.

		 *

	 * So what is the problem, why we need to drop those nodes? Whey can't

	 * we just clean-up the second half of B by putting a padding node

	 * there? We can, and this works fine with one exception which was

	 * reproduced with power cut emulation testing and happens extremely

	 * rarely. The description follows, but it is worth noting that that is

	 * only about the GC head, so we could do this trick only if the bud

	 * belongs to the GC head, but it does not seem to be worth an

	 * additional "if" statement.

		 * So what is the problem, why we need to drop those nodes? Why

		 * can't we just clean-up the second half of B by putting a

		 * padding node there? We can, and this works fine with one

		 * exception which was reproduced with power cut emulation

		 * testing and happens extremely rarely.

		 *

	 * So, imagine the file-system is full, we run GC which is moving valid

	 * nodes from LEB X to LEB Y (obviously, LEB Y is the current GC head

	 * LEB). The @c->gc_lnum is -1, which means that GC will retain LEB X

	 * and will try to continue. Imagine that LEB X is currently the

	 * dirtiest LEB, and the amount of used space in LEB Y is exactly the

	 * same as amount of free space in LEB X.

		 * Imagine the file-system is full, we run GC which starts

		 * moving valid nodes from LEB X to LEB Y (obviously, LEB Y is

		 * the current GC head LEB). The @c->gc_lnum is -1, which means

		 * that GC will retain LEB X and will try to continue. Imagine

		 * that LEB X is currently the dirtiest LEB, and the amount of

		 * used space in LEB Y is exactly the same as amount of free

		 * space in LEB X.

		 *

	 * And a power cut happens when nodes are moved from LEB X to LEB Y. We

	 * are here trying to recover LEB Y which is the GC head LEB. We find

	 * the min. I/O unit B as described above. Then we clean-up LEB Y by

	 * padding min. I/O unit. And later 'ubifs_rcvry_gc_commit()' function

	 * fails, because it cannot find a dirty LEB which could be GC'd into

	 * LEB Y! Even LEB X does not match because the amount of valid nodes

	 * there does not fit the free space in LEB Y any more! And this is

		 * And a power cut happens when nodes are moved from LEB X to

		 * LEB Y. We are here trying to recover LEB Y which is the GC

		 * head LEB. We find the min. I/O unit B as described above.

		 * Then we clean-up LEB Y by padding min. I/O unit. And later

		 * 'ubifs_rcvry_gc_commit()' function fails, because it cannot

		 * find a dirty LEB which could be GC'd into LEB Y! Even LEB X

		 * does not match because the amount of valid nodes there does

		 * not fit the free space in LEB Y any more! And this is

		 * because of the padding node which we added to LEB Y. The

	 * user-visible effect of this which I once observed and analysed is

	 * that we cannot mount the file-system with -ENOSPC error.

		 * user-visible effect of this which I once observed and

		 * analysed is that we cannot mount the file-system with

		 * -ENOSPC error.

		 *

	 * So obviously, to make sure that situation does not happen we should

	 * free min. I/O unit B in LEB Y completely and the last used min. I/O

	 * unit in LEB Y should be A. This is basically what the below code

	 * tries to do.

		 * So obviously, to make sure that situation does not happen we

		 * should free min. I/O unit B in LEB Y completely and the last

		 * used min. I/O unit in LEB Y should be A. This is basically

		 * what the below code tries to do.

		 */

	while (min_io_unit == round_down(offs, c->min_io_size) &&

	       min_io_unit != offs &&

	       drop_last_node(sleb, &offs, grouped));

		while (offs > min_io_unit)

			drop_last_node(sleb, &offs);

	}



	buf = sbuf + offs;

	len = c->leb_size - offs;
@@ -881,7 +905,7 @@ struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum, 
		}

		ubifs_scan_destroy(sleb);

	}

	return ubifs_recover_leb(c, lnum, offs, sbuf, 0);

	return ubifs_recover_leb(c, lnum, offs, sbuf, -1);

}



/**

fs/ubifs/replay.c

+1 −2
Original line number Diff line number Diff line
@@ -557,8 +557,7 @@ static int replay_bud(struct ubifs_info *c, struct bud_entry *b) 
		 * these LEBs could possibly be written to at the power cut

		 * time.

		 */

		sleb = ubifs_recover_leb(c, lnum, offs, c->sbuf,

					 b->bud->jhead != GCHD);

		sleb = ubifs_recover_leb(c, lnum, offs, c->sbuf, b->bud->jhead);

	else

		sleb = ubifs_scan(c, lnum, offs, c->sbuf, 0);

	if (IS_ERR(sleb))

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