[patch 15/39] ext4: Add support for non-native signed/unsigned htree hash algorithms

[patch 15/39] ext4: Add support for non-native signed/unsigned htree hash algorithms

[Greg KH]

[-- Attachment #1: ext4-add-support-for-non-native-signed-unsigned-htree-hash-algorithms.patch --]
[-- Type: text/plain, Size: 6862 bytes --]

2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: "Theodore Ts'o" <tytso@mit.edu>

(cherry picked from commit f99b25897a86fcfff9140396a97261ae65fed872)

The original ext3 hash algorithms assumed that variables of type char
were signed, as God and K&R intended.  Unfortunately, this assumption
is not true on some architectures.  Userspace support for marking
filesystems with non-native signed/unsigned chars was added two years
ago, but the kernel-side support was never added (until now).

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/ext4.h    |    3 ++
 fs/ext4/ext4_sb.h |    1 
 fs/ext4/hash.c    |   77 ++++++++++++++++++++++++++++++++++++++++++++++--------
 fs/ext4/namei.c   |    7 ++++
 fs/ext4/super.c   |   12 ++++++++
 5 files changed, 90 insertions(+), 10 deletions(-)

--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -891,6 +891,9 @@ static inline __le16 ext4_rec_len_to_dis
 #define DX_HASH_LEGACY		0
 #define DX_HASH_HALF_MD4	1
 #define DX_HASH_TEA		2
+#define DX_HASH_LEGACY_UNSIGNED	3
+#define DX_HASH_HALF_MD4_UNSIGNED	4
+#define DX_HASH_TEA_UNSIGNED		5
 
 #ifdef __KERNEL__
 
--- a/fs/ext4/ext4_sb.h
+++ b/fs/ext4/ext4_sb.h
@@ -57,6 +57,7 @@ struct ext4_sb_info {
 	u32 s_next_generation;
 	u32 s_hash_seed[4];
 	int s_def_hash_version;
+	int s_hash_unsigned;	/* 3 if hash should be signed, 0 if not */
 	struct percpu_counter s_freeblocks_counter;
 	struct percpu_counter s_freeinodes_counter;
 	struct percpu_counter s_dirs_counter;
--- a/fs/ext4/hash.c
+++ b/fs/ext4/hash.c
@@ -35,23 +35,71 @@ static void TEA_transform(__u32 buf[4], 
 
 
 /* The old legacy hash */
-static __u32 dx_hack_hash(const char *name, int len)
+static __u32 dx_hack_hash_unsigned(const char *name, int len)
 {
-	__u32 hash0 = 0x12a3fe2d, hash1 = 0x37abe8f9;
+	__u32 hash, hash0 = 0x12a3fe2d, hash1 = 0x37abe8f9;
+	const unsigned char *ucp = (const unsigned char *) name;
+
+	while (len--) {
+		hash = hash1 + (hash0 ^ (((int) *ucp++) * 7152373));
+
+		if (hash & 0x80000000)
+			hash -= 0x7fffffff;
+		hash1 = hash0;
+		hash0 = hash;
+	}
+	return hash0 << 1;
+}
+
+static __u32 dx_hack_hash_signed(const char *name, int len)
+{
+	__u32 hash, hash0 = 0x12a3fe2d, hash1 = 0x37abe8f9;
+	const signed char *scp = (const signed char *) name;
+
 	while (len--) {
-		__u32 hash = hash1 + (hash0 ^ (*name++ * 7152373));
+		hash = hash1 + (hash0 ^ (((int) *scp++) * 7152373));
 
-		if (hash & 0x80000000) hash -= 0x7fffffff;
+		if (hash & 0x80000000)
+			hash -= 0x7fffffff;
 		hash1 = hash0;
 		hash0 = hash;
 	}
-	return (hash0 << 1);
+	return hash0 << 1;
+}
+
+static void str2hashbuf_signed(const char *msg, int len, __u32 *buf, int num)
+{
+	__u32	pad, val;
+	int	i;
+	const signed char *scp = (const signed char *) msg;
+
+	pad = (__u32)len | ((__u32)len << 8);
+	pad |= pad << 16;
+
+	val = pad;
+	if (len > num*4)
+		len = num * 4;
+	for (i = 0; i < len; i++) {
+		if ((i % 4) == 0)
+			val = pad;
+		val = ((int) scp[i]) + (val << 8);
+		if ((i % 4) == 3) {
+			*buf++ = val;
+			val = pad;
+			num--;
+		}
+	}
+	if (--num >= 0)
+		*buf++ = val;
+	while (--num >= 0)
+		*buf++ = pad;
 }
 
-static void str2hashbuf(const char *msg, int len, __u32 *buf, int num)
+static void str2hashbuf_unsigned(const char *msg, int len, __u32 *buf, int num)
 {
 	__u32	pad, val;
 	int	i;
+	const unsigned char *ucp = (const unsigned char *) msg;
 
 	pad = (__u32)len | ((__u32)len << 8);
 	pad |= pad << 16;
@@ -62,7 +110,7 @@ static void str2hashbuf(const char *msg,
 	for (i = 0; i < len; i++) {
 		if ((i % 4) == 0)
 			val = pad;
-		val = msg[i] + (val << 8);
+		val = ((int) ucp[i]) + (val << 8);
 		if ((i % 4) == 3) {
 			*buf++ = val;
 			val = pad;
@@ -95,6 +143,8 @@ int ext4fs_dirhash(const char *name, int
 	const char	*p;
 	int		i;
 	__u32		in[8], buf[4];
+	void		(*str2hashbuf)(const char *, int, __u32 *, int) =
+				str2hashbuf_signed;
 
 	/* Initialize the default seed for the hash checksum functions */
 	buf[0] = 0x67452301;
@@ -113,13 +163,18 @@ int ext4fs_dirhash(const char *name, int
 	}
 
 	switch (hinfo->hash_version) {
+	case DX_HASH_LEGACY_UNSIGNED:
+		hash = dx_hack_hash_unsigned(name, len);
+		break;
 	case DX_HASH_LEGACY:
-		hash = dx_hack_hash(name, len);
+		hash = dx_hack_hash_signed(name, len);
 		break;
+	case DX_HASH_HALF_MD4_UNSIGNED:
+		str2hashbuf = str2hashbuf_unsigned;
 	case DX_HASH_HALF_MD4:
 		p = name;
 		while (len > 0) {
-			str2hashbuf(p, len, in, 8);
+			(*str2hashbuf)(p, len, in, 8);
 			half_md4_transform(buf, in);
 			len -= 32;
 			p += 32;
@@ -127,10 +182,12 @@ int ext4fs_dirhash(const char *name, int
 		minor_hash = buf[2];
 		hash = buf[1];
 		break;
+	case DX_HASH_TEA_UNSIGNED:
+		str2hashbuf = str2hashbuf_unsigned;
 	case DX_HASH_TEA:
 		p = name;
 		while (len > 0) {
-			str2hashbuf(p, len, in, 4);
+			(*str2hashbuf)(p, len, in, 4);
 			TEA_transform(buf, in);
 			len -= 16;
 			p += 16;
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -372,6 +372,8 @@ dx_probe(const struct qstr *d_name, stru
 		goto fail;
 	}
 	hinfo->hash_version = root->info.hash_version;
+	if (hinfo->hash_version <= DX_HASH_TEA)
+		hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
 	hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed;
 	if (d_name)
 		ext4fs_dirhash(d_name->name, d_name->len, hinfo);
@@ -641,6 +643,9 @@ int ext4_htree_fill_tree(struct file *di
 	dir = dir_file->f_path.dentry->d_inode;
 	if (!(EXT4_I(dir)->i_flags & EXT4_INDEX_FL)) {
 		hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
+		if (hinfo.hash_version <= DX_HASH_TEA)
+			hinfo.hash_version +=
+				EXT4_SB(dir->i_sb)->s_hash_unsigned;
 		hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
 		count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo,
 					       start_hash, start_minor_hash);
@@ -1408,6 +1413,8 @@ static int make_indexed_dir(handle_t *ha
 
 	/* Initialize as for dx_probe */
 	hinfo.hash_version = root->info.hash_version;
+	if (hinfo.hash_version <= DX_HASH_TEA)
+		hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
 	hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
 	ext4fs_dirhash(name, namelen, &hinfo);
 	frame = frames;
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -2118,6 +2118,18 @@ static int ext4_fill_super(struct super_
 	for (i = 0; i < 4; i++)
 		sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
 	sbi->s_def_hash_version = es->s_def_hash_version;
+	i = le32_to_cpu(es->s_flags);
+	if (i & EXT2_FLAGS_UNSIGNED_HASH)
+		sbi->s_hash_unsigned = 3;
+	else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
+#ifdef __CHAR_UNSIGNED__
+		es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
+		sbi->s_hash_unsigned = 3;
+#else
+		es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
+#endif
+		sb->s_dirt = 1;
+	}
 
 	if (sbi->s_blocks_per_group > blocksize * 8) {
 		printk(KERN_ERR

[patch 16/39] ext4: tone down ext4_da_writepages warnings

[Greg KH]

[-- Attachment #1: ext4-tone-down-ext4_da_writepages-warnings.patch --]
[-- Type: text/plain, Size: 2013 bytes --]

2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: "Theodore Ts'o" <tytso@mit.edu>

(cherry picked from commit 2a21e37e48b94388f2cc8c0392f104f5443d4bb8)

If the filesystem has errors, ext4_da_writepages() will return a *lot*
of errors, including lots and lots of stack dumps.  While it's true
that we are dropping user data on the floor, which is unfortunate, the
stack dumps aren't helpful, and they tend to obscure the true original
root cause of the problem.  So in the case where the filesystem has
aborted, return an EROFS right away.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/inode.c |   16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -2388,6 +2388,20 @@ static int ext4_da_writepages(struct add
 	 */
 	if (!mapping->nrpages || !mapping_tagged(mapping, PAGECACHE_TAG_DIRTY))
 		return 0;
+
+	/*
+	 * If the filesystem has aborted, it is read-only, so return
+	 * right away instead of dumping stack traces later on that
+	 * will obscure the real source of the problem.  We test
+	 * EXT4_MOUNT_ABORT instead of sb->s_flag's MS_RDONLY because
+	 * the latter could be true if the filesystem is mounted
+	 * read-only, and in that case, ext4_da_writepages should
+	 * *never* be called, so if that ever happens, we would want
+	 * the stack trace.
+	 */
+	if (unlikely(sbi->s_mount_opt & EXT4_MOUNT_ABORT))
+		return -EROFS;
+
 	/*
 	 * Make sure nr_to_write is >= sbi->s_mb_stream_request
 	 * This make sure small files blocks are allocated in
@@ -2432,7 +2446,7 @@ static int ext4_da_writepages(struct add
 		handle = ext4_journal_start(inode, needed_blocks);
 		if (IS_ERR(handle)) {
 			ret = PTR_ERR(handle);
-			printk(KERN_EMERG "%s: jbd2_start: "
+			printk(KERN_CRIT "%s: jbd2_start: "
 			       "%ld pages, ino %lu; err %d\n", __func__,
 				wbc->nr_to_write, inode->i_ino, ret);
 			dump_stack();

[patch 17/39] ext4: Fix the delalloc writepages to allocate blocks at the right offset.

[Greg KH]

[-- Attachment #1: ext4-fix-the-delalloc-writepages-to-allocate-blocks-at-the-right-offset.patch --]
[-- Type: text/plain, Size: 3563 bytes --]


2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

(cherry picked from commit 791b7f08954869d7b8ff438f3dac3cfb39778297)

When iterating through the pages which have mapped buffer_heads, we
failed to update the b_state value. This results in allocating blocks
at logical offset 0.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/inode.c |   56 +++++++++++++++++++++++++++++++++++++++-----------------
 1 file changed, 39 insertions(+), 17 deletions(-)

--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1644,35 +1644,39 @@ struct mpage_da_data {
  */
 static int mpage_da_submit_io(struct mpage_da_data *mpd)
 {
-	struct address_space *mapping = mpd->inode->i_mapping;
-	int ret = 0, err, nr_pages, i;
-	unsigned long index, end;
-	struct pagevec pvec;
 	long pages_skipped;
+	struct pagevec pvec;
+	unsigned long index, end;
+	int ret = 0, err, nr_pages, i;
+	struct inode *inode = mpd->inode;
+	struct address_space *mapping = inode->i_mapping;
 
 	BUG_ON(mpd->next_page <= mpd->first_page);
-	pagevec_init(&pvec, 0);
+	/*
+	 * We need to start from the first_page to the next_page - 1
+	 * to make sure we also write the mapped dirty buffer_heads.
+	 * If we look at mpd->lbh.b_blocknr we would only be looking
+	 * at the currently mapped buffer_heads.
+	 */
 	index = mpd->first_page;
 	end = mpd->next_page - 1;
 
+	pagevec_init(&pvec, 0);
 	while (index <= end) {
-		/*
-		 * We can use PAGECACHE_TAG_DIRTY lookup here because
-		 * even though we have cleared the dirty flag on the page
-		 * We still keep the page in the radix tree with tag
-		 * PAGECACHE_TAG_DIRTY. See clear_page_dirty_for_io.
-		 * The PAGECACHE_TAG_DIRTY is cleared in set_page_writeback
-		 * which is called via the below writepage callback.
-		 */
-		nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
-					PAGECACHE_TAG_DIRTY,
-					min(end - index,
-					(pgoff_t)PAGEVEC_SIZE-1) + 1);
+		nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE);
 		if (nr_pages == 0)
 			break;
 		for (i = 0; i < nr_pages; i++) {
 			struct page *page = pvec.pages[i];
 
+			index = page->index;
+			if (index > end)
+				break;
+			index++;
+
+			BUG_ON(!PageLocked(page));
+			BUG_ON(PageWriteback(page));
+
 			pages_skipped = mpd->wbc->pages_skipped;
 			err = mapping->a_ops->writepage(page, mpd->wbc);
 			if (!err && (pages_skipped == mpd->wbc->pages_skipped))
@@ -2086,11 +2090,29 @@ static int __mpage_da_writepage(struct p
 		bh = head;
 		do {
 			BUG_ON(buffer_locked(bh));
+			/*
+			 * We need to try to allocate
+			 * unmapped blocks in the same page.
+			 * Otherwise we won't make progress
+			 * with the page in ext4_da_writepage
+			 */
 			if (buffer_dirty(bh) &&
 				(!buffer_mapped(bh) || buffer_delay(bh))) {
 				mpage_add_bh_to_extent(mpd, logical, bh);
 				if (mpd->io_done)
 					return MPAGE_DA_EXTENT_TAIL;
+			} else if (buffer_dirty(bh) && (buffer_mapped(bh))) {
+				/*
+				 * mapped dirty buffer. We need to update
+				 * the b_state because we look at
+				 * b_state in mpage_da_map_blocks. We don't
+				 * update b_size because if we find an
+				 * unmapped buffer_head later we need to
+				 * use the b_state flag of that buffer_head.
+				 */
+				if (mpd->lbh.b_size == 0)
+					mpd->lbh.b_state =
+						bh->b_state & BH_FLAGS;
 			}
 			logical++;
 		} while ((bh = bh->b_this_page) != head);

[patch 18/39] ext4: avoid ext4_error when mounting a fs with a single bg

[Greg KH]

[-- Attachment #1: ext4-avoid-ext4_error-when-mounting-a-fs-with-a-single-bg.patch --]
[-- Type: text/plain, Size: 1055 bytes --]

2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

(cherry picked from commit 565a9617b2151e21b22700e97a8b04e70e103153)

Remove some completely unneeded code which which caused an ext4_error
to be generated when mounting a file system with only a single block
group.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/super.c |    4 ----
 1 file changed, 4 deletions(-)

--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1445,7 +1445,6 @@ static int ext4_fill_flex_info(struct su
 	ext4_group_t flex_group_count;
 	ext4_group_t flex_group;
 	int groups_per_flex = 0;
-	__u64 block_bitmap = 0;
 	int i;
 
 	if (!sbi->s_es->s_log_groups_per_flex) {
@@ -1468,9 +1467,6 @@ static int ext4_fill_flex_info(struct su
 		goto failed;
 	}
 
-	gdp = ext4_get_group_desc(sb, 1, &bh);
-	block_bitmap = ext4_block_bitmap(sb, gdp) - 1;

[patch 19/39] ext4: Widen type of ext4_sb_info.s_mb_maxs[]

[Greg KH]

[-- Attachment #1: ext4-widen-type-of-ext4_sb_info.s_mb_maxs.patch --]
[-- Type: text/plain, Size: 1564 bytes --]


2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Yasunori Goto <y-goto@jp.fujitsu.com>

(cherry picked from commit ff7ef329b268b603ea4a2303241ef1c3829fd574)

I chased the cause of following ext4 oops report which is tested on
ia64 box.

http://bugzilla.kernel.org/show_bug.cgi?id=12018

The cause is the size of s_mb_maxs array that is defined as "unsigned
short" in ext4_sb_info structure.  If the file system's block size is
8k or greater, an unsigned short is not wide enough to contain the
value fs->blocksize << 3.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/ext4_sb.h |    3 ++-
 fs/ext4/mballoc.c |    2 ++
 2 files changed, 4 insertions(+), 1 deletion(-)

--- a/fs/ext4/ext4_sb.h
+++ b/fs/ext4/ext4_sb.h
@@ -102,7 +102,8 @@ struct ext4_sb_info {
 	spinlock_t s_reserve_lock;
 	spinlock_t s_md_lock;
 	tid_t s_last_transaction;
-	unsigned short *s_mb_offsets, *s_mb_maxs;
+	unsigned short *s_mb_offsets;
+	unsigned int *s_mb_maxs;
 
 	/* tunables */
 	unsigned long s_stripe;
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -2493,6 +2493,8 @@ int ext4_mb_init(struct super_block *sb,
 	if (sbi->s_mb_offsets == NULL) {
 		return -ENOMEM;
 	}
+
+	i = (sb->s_blocksize_bits + 2) * sizeof(unsigned int);
 	sbi->s_mb_maxs = kmalloc(i, GFP_KERNEL);
 	if (sbi->s_mb_maxs == NULL) {
 		kfree(sbi->s_mb_maxs);

[patch 20/39] jbd2: Add barrier not supported test to journal_wait_on_commit_record

[Greg KH]

[-- Attachment #1: jbd2-add-barrier-not-supported-test-to-journal_wait_on_commit_record.patch --]
[-- Type: text/plain, Size: 2434 bytes --]

2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: "Theodore Ts'o" <tytso@mit.edu>

(cherry picked from commit fd98496f467b3d26d05ab1498f41718b5ef13de5)

Xen doesn't report that barriers are not supported until buffer I/O is
reported as completed, instead of when the buffer I/O is submitted.
Add a check and a fallback codepath to journal_wait_on_commit_record()
to detect this case, so that attempts to mount ext4 filesystems on
LVM/devicemapper devices on Xen guests don't blow up with an "Aborting
journal on device XXX"; "Remounting filesystem read-only" error.

Thanks to Andreas Sundstrom for reporting this issue.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/jbd2/commit.c |   27 +++++++++++++++++++++++++--
 1 file changed, 25 insertions(+), 2 deletions(-)

--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -25,6 +25,7 @@
 #include <linux/crc32.h>
 #include <linux/writeback.h>
 #include <linux/backing-dev.h>
+#include <linux/bio.h>
 
 /*
  * Default IO end handler for temporary BJ_IO buffer_heads.
@@ -168,12 +169,34 @@ static int journal_submit_commit_record(
  * This function along with journal_submit_commit_record
  * allows to write the commit record asynchronously.
  */
-static int journal_wait_on_commit_record(struct buffer_head *bh)
+static int journal_wait_on_commit_record(journal_t *journal,
+					 struct buffer_head *bh)
 {
 	int ret = 0;
 
+retry:
 	clear_buffer_dirty(bh);
 	wait_on_buffer(bh);
+	if (buffer_eopnotsupp(bh) && (journal->j_flags & JBD2_BARRIER)) {
+		printk(KERN_WARNING
+		       "JBD2: wait_on_commit_record: sync failed on %s - "
+		       "disabling barriers\n", journal->j_devname);
+		spin_lock(&journal->j_state_lock);
+		journal->j_flags &= ~JBD2_BARRIER;
+		spin_unlock(&journal->j_state_lock);
+
+		lock_buffer(bh);
+		clear_buffer_dirty(bh);
+		set_buffer_uptodate(bh);
+		bh->b_end_io = journal_end_buffer_io_sync;
+
+		ret = submit_bh(WRITE_SYNC, bh);
+		if (ret) {
+			unlock_buffer(bh);
+			return ret;
+		}
+		goto retry;
+	}
 
 	if (unlikely(!buffer_uptodate(bh)))
 		ret = -EIO;
@@ -799,7 +822,7 @@ wait_for_iobuf:
 			__jbd2_journal_abort_hard(journal);
 	}
 	if (!err && !is_journal_aborted(journal))
-		err = journal_wait_on_commit_record(cbh);
+		err = journal_wait_on_commit_record(journal, cbh);
 
 	if (err)
 		jbd2_journal_abort(journal, err);

[patch 21/39] ext4: Dont overwrite allocation_context ac_status

[Greg KH]

[-- Attachment #1: ext4-don-t-overwrite-allocation_context-ac_status.patch --]
[-- Type: text/plain, Size: 1449 bytes --]


2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

(cherry picked from commit 032115fcef837a00336ddf7bda584e89789ea498)

We can call ext4_mb_check_limits even after successfully allocating
the requested blocks.  In that case, make sure we don't overwrite
ac_status if it already has the status AC_STATUS_FOUND.  This fixes
the lockdep warning:

=============================================
[ INFO: possible recursive locking detected ]
2.6.28-rc6-autokern1 #1
---------------------------------------------
fsstress/11948 is trying to acquire lock:
 (&meta_group_info[i]->alloc_sem){----}, at: [<c04d9a49>] ext4_mb_load_buddy+0x9f/0x278
.....

stack backtrace:
.....
 [<c04db974>] ext4_mb_regular_allocator+0xbb5/0xd44
.....

but task is already holding lock:
 (&meta_group_info[i]->alloc_sem){----}, at: [<c04d9a49>] ext4_mb_load_buddy+0x9f/0x278

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
 fs/ext4/mballoc.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -1326,6 +1326,8 @@ static void ext4_mb_check_limits(struct 
 	struct ext4_free_extent ex;
 	int max;
 
+	if (ac->ac_status == AC_STATUS_FOUND)
+		return;
 	/*
 	 * We don't want to scan for a whole year
 	 */

[patch 22/39] ext4: Add blocks added during resize to bitmap

[Greg KH]

[-- Attachment #1: ext4-add-blocks-added-during-resize-to-bitmap.patch --]
[-- Type: text/plain, Size: 10225 bytes --]


2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

(cherry picked from commit e21675d4b63975d09eb75c443c48ebe663d23e18)

With this change new blocks added during resize
are marked as free in the block bitmap and the
group is flagged with EXT4_GROUP_INFO_NEED_INIT_BIT
flag.  This makes sure when mballoc tries to allocate
blocks from the new group we would reload the
buddy information using the bitmap present in the disk.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/balloc.c |  138 ++++++++++++-------------------------------------------
 fs/ext4/ext4.h   |    5 -
 fs/ext4/resize.c |   11 ----
 3 files changed, 35 insertions(+), 119 deletions(-)

--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -20,6 +20,7 @@
 #include "ext4.h"
 #include "ext4_jbd2.h"
 #include "group.h"
+#include "mballoc.h"
 
 /*
  * balloc.c contains the blocks allocation and deallocation routines
@@ -350,62 +351,43 @@ ext4_read_block_bitmap(struct super_bloc
 }
 
 /**
- * ext4_free_blocks_sb() -- Free given blocks and update quota
+ * ext4_add_groupblocks() -- Add given blocks to an existing group
  * @handle:			handle to this transaction
  * @sb:				super block
- * @block:			start physcial block to free
+ * @block:			start physcial block to add to the block group
  * @count:			number of blocks to free
- * @pdquot_freed_blocks:	pointer to quota
  *
- * XXX This function is only used by the on-line resizing code, which
- * should probably be fixed up to call the mballoc variant.  There
- * this needs to be cleaned up later; in fact, I'm not convinced this
- * is 100% correct in the face of the mballoc code.  The online resizing
- * code needs to be fixed up to more tightly (and correctly) interlock
- * with the mballoc code.
- */
-void ext4_free_blocks_sb(handle_t *handle, struct super_block *sb,
-			 ext4_fsblk_t block, unsigned long count,
-			 unsigned long *pdquot_freed_blocks)
+ * This marks the blocks as free in the bitmap. We ask the
+ * mballoc to reload the buddy after this by setting group
+ * EXT4_GROUP_INFO_NEED_INIT_BIT flag
+ */
+void ext4_add_groupblocks(handle_t *handle, struct super_block *sb,
+			 ext4_fsblk_t block, unsigned long count)
 {
 	struct buffer_head *bitmap_bh = NULL;
 	struct buffer_head *gd_bh;
 	ext4_group_t block_group;
 	ext4_grpblk_t bit;
 	unsigned long i;
-	unsigned long overflow;
 	struct ext4_group_desc *desc;
 	struct ext4_super_block *es;
 	struct ext4_sb_info *sbi;
 	int err = 0, ret;
-	ext4_grpblk_t group_freed;
+	ext4_grpblk_t blocks_freed;
+	struct ext4_group_info *grp;
 
-	*pdquot_freed_blocks = 0;
 	sbi = EXT4_SB(sb);
 	es = sbi->s_es;
-	if (block < le32_to_cpu(es->s_first_data_block) ||
-	    block + count < block ||
-	    block + count > ext4_blocks_count(es)) {
-		ext4_error(sb, "ext4_free_blocks",
-			   "Freeing blocks not in datazone - "
-			   "block = %llu, count = %lu", block, count);
-		goto error_return;
-	}
+	ext4_debug("Adding block(s) %llu-%llu\n", block, block + count - 1);
 
-	ext4_debug("freeing block(s) %llu-%llu\n", block, block + count - 1);
-
-do_more:
-	overflow = 0;
 	ext4_get_group_no_and_offset(sb, block, &block_group, &bit);
 	/*
 	 * Check to see if we are freeing blocks across a group
 	 * boundary.
 	 */
 	if (bit + count > EXT4_BLOCKS_PER_GROUP(sb)) {
-		overflow = bit + count - EXT4_BLOCKS_PER_GROUP(sb);
-		count -= overflow;
+		goto error_return;
 	}
-	brelse(bitmap_bh);
 	bitmap_bh = ext4_read_block_bitmap(sb, block_group);
 	if (!bitmap_bh)
 		goto error_return;
@@ -418,18 +400,17 @@ do_more:
 	    in_range(block, ext4_inode_table(sb, desc), sbi->s_itb_per_group) ||
 	    in_range(block + count - 1, ext4_inode_table(sb, desc),
 		     sbi->s_itb_per_group)) {
-		ext4_error(sb, "ext4_free_blocks",
-			   "Freeing blocks in system zones - "
+		ext4_error(sb, __func__,
+			   "Adding blocks in system zones - "
 			   "Block = %llu, count = %lu",
 			   block, count);
 		goto error_return;
 	}
 
 	/*
-	 * We are about to start releasing blocks in the bitmap,
+	 * We are about to add blocks to the bitmap,
 	 * so we need undo access.
 	 */
-	/* @@@ check errors */
 	BUFFER_TRACE(bitmap_bh, "getting undo access");
 	err = ext4_journal_get_undo_access(handle, bitmap_bh);
 	if (err)
@@ -445,87 +426,28 @@ do_more:
 	if (err)
 		goto error_return;
 
-	jbd_lock_bh_state(bitmap_bh);
-
-	for (i = 0, group_freed = 0; i < count; i++) {
-		/*
-		 * An HJ special.  This is expensive...
-		 */
-#ifdef CONFIG_JBD2_DEBUG
-		jbd_unlock_bh_state(bitmap_bh);
-		{
-			struct buffer_head *debug_bh;
-			debug_bh = sb_find_get_block(sb, block + i);
-			if (debug_bh) {
-				BUFFER_TRACE(debug_bh, "Deleted!");
-				if (!bh2jh(bitmap_bh)->b_committed_data)
-					BUFFER_TRACE(debug_bh,
-						"No commited data in bitmap");
-				BUFFER_TRACE2(debug_bh, bitmap_bh, "bitmap");
-				__brelse(debug_bh);
-			}
-		}
-		jbd_lock_bh_state(bitmap_bh);
-#endif
-		if (need_resched()) {
-			jbd_unlock_bh_state(bitmap_bh);
-			cond_resched();
-			jbd_lock_bh_state(bitmap_bh);
-		}
-		/* @@@ This prevents newly-allocated data from being
-		 * freed and then reallocated within the same
-		 * transaction.
-		 *
-		 * Ideally we would want to allow that to happen, but to
-		 * do so requires making jbd2_journal_forget() capable of
-		 * revoking the queued write of a data block, which
-		 * implies blocking on the journal lock.  *forget()
-		 * cannot block due to truncate races.
-		 *
-		 * Eventually we can fix this by making jbd2_journal_forget()
-		 * return a status indicating whether or not it was able
-		 * to revoke the buffer.  On successful revoke, it is
-		 * safe not to set the allocation bit in the committed
-		 * bitmap, because we know that there is no outstanding
-		 * activity on the buffer any more and so it is safe to
-		 * reallocate it.
-		 */
-		BUFFER_TRACE(bitmap_bh, "set in b_committed_data");
-		J_ASSERT_BH(bitmap_bh,
-				bh2jh(bitmap_bh)->b_committed_data != NULL);
-		ext4_set_bit_atomic(sb_bgl_lock(sbi, block_group), bit + i,
-				bh2jh(bitmap_bh)->b_committed_data);
-
-		/*
-		 * We clear the bit in the bitmap after setting the committed
-		 * data bit, because this is the reverse order to that which
-		 * the allocator uses.
-		 */
+	for (i = 0, blocks_freed = 0; i < count; i++) {
 		BUFFER_TRACE(bitmap_bh, "clear bit");
 		if (!ext4_clear_bit_atomic(sb_bgl_lock(sbi, block_group),
 						bit + i, bitmap_bh->b_data)) {
-			jbd_unlock_bh_state(bitmap_bh);
 			ext4_error(sb, __func__,
 				   "bit already cleared for block %llu",
 				   (ext4_fsblk_t)(block + i));
-			jbd_lock_bh_state(bitmap_bh);
 			BUFFER_TRACE(bitmap_bh, "bit already cleared");
 		} else {
-			group_freed++;
+			blocks_freed++;
 		}
 	}
-	jbd_unlock_bh_state(bitmap_bh);
-
 	spin_lock(sb_bgl_lock(sbi, block_group));
-	le16_add_cpu(&desc->bg_free_blocks_count, group_freed);
+	le16_add_cpu(&desc->bg_free_blocks_count, blocks_freed);
 	desc->bg_checksum = ext4_group_desc_csum(sbi, block_group, desc);
 	spin_unlock(sb_bgl_lock(sbi, block_group));
-	percpu_counter_add(&sbi->s_freeblocks_counter, count);
+	percpu_counter_add(&sbi->s_freeblocks_counter, blocks_freed);
 
 	if (sbi->s_log_groups_per_flex) {
 		ext4_group_t flex_group = ext4_flex_group(sbi, block_group);
 		spin_lock(sb_bgl_lock(sbi, flex_group));
-		sbi->s_flex_groups[flex_group].free_blocks += count;
+		sbi->s_flex_groups[flex_group].free_blocks += blocks_freed;
 		spin_unlock(sb_bgl_lock(sbi, flex_group));
 	}
 
@@ -536,15 +458,17 @@ do_more:
 	/* And the group descriptor block */
 	BUFFER_TRACE(gd_bh, "dirtied group descriptor block");
 	ret = ext4_journal_dirty_metadata(handle, gd_bh);
-	if (!err) err = ret;
-	*pdquot_freed_blocks += group_freed;
-
-	if (overflow && !err) {
-		block += count;
-		count = overflow;
-		goto do_more;
-	}
+	if (!err)
+		err = ret;
 	sb->s_dirt = 1;
+	/*
+	 * request to reload the buddy with the
+	 * new bitmap information
+	 */
+	grp = ext4_get_group_info(sb, block_group);
+	set_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &(grp->bb_state));
+	ext4_mb_update_group_info(grp, blocks_freed);
+
 error_return:
 	brelse(bitmap_bh);
 	ext4_std_error(sb, err);
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1009,9 +1009,8 @@ extern int ext4_claim_free_blocks(struct
 extern int ext4_has_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
 			ext4_fsblk_t block, unsigned long count, int metadata);
-extern void ext4_free_blocks_sb(handle_t *handle, struct super_block *sb,
-				ext4_fsblk_t block, unsigned long count,
-				unsigned long *pdquot_freed_blocks);
+extern void ext4_add_groupblocks(handle_t *handle, struct super_block *sb,
+				ext4_fsblk_t block, unsigned long count);
 extern ext4_fsblk_t ext4_count_free_blocks(struct super_block *);
 extern void ext4_check_blocks_bitmap(struct super_block *);
 extern struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -975,9 +975,7 @@ int ext4_group_extend(struct super_block
 	struct buffer_head *bh;
 	handle_t *handle;
 	int err;
-	unsigned long freed_blocks;
 	ext4_group_t group;
-	struct ext4_group_info *grp;
 
 	/* We don't need to worry about locking wrt other resizers just
 	 * yet: we're going to revalidate es->s_blocks_count after
@@ -1076,7 +1074,8 @@ int ext4_group_extend(struct super_block
 	unlock_super(sb);
 	ext4_debug("freeing blocks %llu through %llu\n", o_blocks_count,
 		   o_blocks_count + add);
-	ext4_free_blocks_sb(handle, sb, o_blocks_count, add, &freed_blocks);
+	/* We add the blocks to the bitmap and set the group need init bit */
+	ext4_add_groupblocks(handle, sb, o_blocks_count, add);
 	ext4_debug("freed blocks %llu through %llu\n", o_blocks_count,
 		   o_blocks_count + add);
 	if ((err = ext4_journal_stop(handle)))
@@ -1119,12 +1118,6 @@ int ext4_group_extend(struct super_block
 			ClearPageUptodate(page);
 			page_cache_release(page);
 		}
-
-		/* Get the info on the last group */
-		grp = ext4_get_group_info(sb, group);

[patch 23/39] ext4: Use EXT4_GROUP_INFO_NEED_INIT_BIT during resize

[Greg KH]

[-- Attachment #1: ext4-use-ext4_group_info_need_init_bit-during-resize.patch --]
[-- Type: text/plain, Size: 16726 bytes --]


2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

(cherry picked from commit 920313a726e04fef0f2c0bcb04ad8229c0e700d8)

The new groups added during resize are flagged as
need_init group. Make sure we properly initialize these
groups. When we have block size < page size and we are adding
new groups the page may still be marked uptodate even though
we haven't initialized the group. While forcing the init
of buddy cache we need to make sure other groups part of the
same page of buddy cache is not using the cache.
group_info->alloc_sem is added to ensure the same.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/balloc.c  |   21 ++--
 fs/ext4/ext4.h    |    7 -
 fs/ext4/mballoc.c |  259 +++++++++++++++++++++++++++++++++++++++++-------------
 fs/ext4/mballoc.h |    3 
 fs/ext4/resize.c  |   49 +---------
 5 files changed, 229 insertions(+), 110 deletions(-)

--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -381,6 +381,7 @@ void ext4_add_groupblocks(handle_t *hand
 	ext4_debug("Adding block(s) %llu-%llu\n", block, block + count - 1);
 
 	ext4_get_group_no_and_offset(sb, block, &block_group, &bit);
+	grp = ext4_get_group_info(sb, block_group);
 	/*
 	 * Check to see if we are freeing blocks across a group
 	 * boundary.
@@ -425,7 +426,11 @@ void ext4_add_groupblocks(handle_t *hand
 	err = ext4_journal_get_write_access(handle, gd_bh);
 	if (err)
 		goto error_return;
-
+	/*
+	 * make sure we don't allow a parallel init on other groups in the
+	 * same buddy cache
+	 */
+	down_write(&grp->alloc_sem);
 	for (i = 0, blocks_freed = 0; i < count; i++) {
 		BUFFER_TRACE(bitmap_bh, "clear bit");
 		if (!ext4_clear_bit_atomic(sb_bgl_lock(sbi, block_group),
@@ -450,6 +455,13 @@ void ext4_add_groupblocks(handle_t *hand
 		sbi->s_flex_groups[flex_group].free_blocks += blocks_freed;
 		spin_unlock(sb_bgl_lock(sbi, flex_group));
 	}
+	/*
+	 * request to reload the buddy with the
+	 * new bitmap information
+	 */
+	set_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &(grp->bb_state));
+	ext4_mb_update_group_info(grp, blocks_freed);
+	up_write(&grp->alloc_sem);
 
 	/* We dirtied the bitmap block */
 	BUFFER_TRACE(bitmap_bh, "dirtied bitmap block");
@@ -461,13 +473,6 @@ void ext4_add_groupblocks(handle_t *hand
 	if (!err)
 		err = ret;
 	sb->s_dirt = 1;
-	/*
-	 * request to reload the buddy with the
-	 * new bitmap information
-	 */
-	grp = ext4_get_group_info(sb, block_group);
-	set_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &(grp->bb_state));
-	ext4_mb_update_group_info(grp, blocks_freed);
 
 error_return:
 	brelse(bitmap_bh);
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1056,12 +1056,13 @@ extern int __init init_ext4_mballoc(void
 extern void exit_ext4_mballoc(void);
 extern void ext4_mb_free_blocks(handle_t *, struct inode *,
 		unsigned long, unsigned long, int, unsigned long *);
-extern int ext4_mb_add_more_groupinfo(struct super_block *sb,
+extern int ext4_mb_add_groupinfo(struct super_block *sb,
 		ext4_group_t i, struct ext4_group_desc *desc);
 extern void ext4_mb_update_group_info(struct ext4_group_info *grp,
 		ext4_grpblk_t add);
-
-
+extern int ext4_mb_get_buddy_cache_lock(struct super_block *, ext4_group_t);
+extern void ext4_mb_put_buddy_cache_lock(struct super_block *,
+						ext4_group_t, int);
 /* inode.c */
 int ext4_forget(handle_t *handle, int is_metadata, struct inode *inode,
 		struct buffer_head *bh, ext4_fsblk_t blocknr);
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -886,18 +886,20 @@ static noinline_for_stack int
 ext4_mb_load_buddy(struct super_block *sb, ext4_group_t group,
 					struct ext4_buddy *e4b)
 {
-	struct ext4_sb_info *sbi = EXT4_SB(sb);
-	struct inode *inode = sbi->s_buddy_cache;
 	int blocks_per_page;
 	int block;
 	int pnum;
 	int poff;
 	struct page *page;
 	int ret;
+	struct ext4_group_info *grp;
+	struct ext4_sb_info *sbi = EXT4_SB(sb);
+	struct inode *inode = sbi->s_buddy_cache;
 
 	mb_debug("load group %lu\n", group);
 
 	blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize;
+	grp = ext4_get_group_info(sb, group);
 
 	e4b->bd_blkbits = sb->s_blocksize_bits;
 	e4b->bd_info = ext4_get_group_info(sb, group);
@@ -905,6 +907,15 @@ ext4_mb_load_buddy(struct super_block *s
 	e4b->bd_group = group;
 	e4b->bd_buddy_page = NULL;
 	e4b->bd_bitmap_page = NULL;
+	e4b->alloc_semp = &grp->alloc_sem;
+
+	/* Take the read lock on the group alloc
+	 * sem. This would make sure a parallel
+	 * ext4_mb_init_group happening on other
+	 * groups mapped by the page is blocked
+	 * till we are done with allocation
+	 */
+	down_read(e4b->alloc_semp);
 
 	/*
 	 * the buddy cache inode stores the block bitmap
@@ -920,6 +931,14 @@ ext4_mb_load_buddy(struct super_block *s
 	page = find_get_page(inode->i_mapping, pnum);
 	if (page == NULL || !PageUptodate(page)) {
 		if (page)
+			/*
+			 * drop the page reference and try
+			 * to get the page with lock. If we
+			 * are not uptodate that implies
+			 * somebody just created the page but
+			 * is yet to initialize the same. So
+			 * wait for it to initialize.
+			 */
 			page_cache_release(page);
 		page = find_or_create_page(inode->i_mapping, pnum, GFP_NOFS);
 		if (page) {
@@ -985,6 +1004,9 @@ err:
 		page_cache_release(e4b->bd_buddy_page);
 	e4b->bd_buddy = NULL;
 	e4b->bd_bitmap = NULL;
+
+	/* Done with the buddy cache */
+	up_read(e4b->alloc_semp);
 	return ret;
 }
 
@@ -994,6 +1016,8 @@ static void ext4_mb_release_desc(struct 
 		page_cache_release(e4b->bd_bitmap_page);
 	if (e4b->bd_buddy_page)
 		page_cache_release(e4b->bd_buddy_page);
+	/* Done with the buddy cache */
+	up_read(e4b->alloc_semp);
 }
 
 
@@ -1694,6 +1718,173 @@ static int ext4_mb_good_group(struct ext
 	return 0;
 }
 
+/*
+ * lock the group_info alloc_sem of all the groups
+ * belonging to the same buddy cache page. This
+ * make sure other parallel operation on the buddy
+ * cache doesn't happen  whild holding the buddy cache
+ * lock
+ */
+int ext4_mb_get_buddy_cache_lock(struct super_block *sb, ext4_group_t group)
+{
+	int i;
+	int block, pnum;
+	int blocks_per_page;
+	int groups_per_page;
+	ext4_group_t first_group;
+	struct ext4_group_info *grp;
+
+	blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize;
+	/*
+	 * the buddy cache inode stores the block bitmap
+	 * and buddy information in consecutive blocks.
+	 * So for each group we need two blocks.
+	 */
+	block = group * 2;
+	pnum = block / blocks_per_page;
+	first_group = pnum * blocks_per_page / 2;
+
+	groups_per_page = blocks_per_page >> 1;
+	if (groups_per_page == 0)
+		groups_per_page = 1;
+	/* read all groups the page covers into the cache */
+	for (i = 0; i < groups_per_page; i++) {
+
+		if ((first_group + i) >= EXT4_SB(sb)->s_groups_count)
+			break;
+		grp = ext4_get_group_info(sb, first_group + i);
+		/* take all groups write allocation
+		 * semaphore. This make sure there is
+		 * no block allocation going on in any
+		 * of that groups
+		 */
+		down_write(&grp->alloc_sem);
+	}
+	return i;
+}
+
+void ext4_mb_put_buddy_cache_lock(struct super_block *sb,
+					ext4_group_t group, int locked_group)
+{
+	int i;
+	int block, pnum;
+	int blocks_per_page;
+	ext4_group_t first_group;
+	struct ext4_group_info *grp;
+
+	blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize;
+	/*
+	 * the buddy cache inode stores the block bitmap
+	 * and buddy information in consecutive blocks.
+	 * So for each group we need two blocks.
+	 */
+	block = group * 2;
+	pnum = block / blocks_per_page;
+	first_group = pnum * blocks_per_page / 2;
+	/* release locks on all the groups */
+	for (i = 0; i < locked_group; i++) {
+
+		grp = ext4_get_group_info(sb, first_group + i);
+		/* take all groups write allocation
+		 * semaphore. This make sure there is
+		 * no block allocation going on in any
+		 * of that groups
+		 */
+		up_write(&grp->alloc_sem);
+	}
+
+}
+
+static int ext4_mb_init_group(struct super_block *sb, ext4_group_t group)
+{
+
+	int ret;
+	void *bitmap;
+	int blocks_per_page;
+	int block, pnum, poff;
+	int num_grp_locked = 0;
+	struct ext4_group_info *this_grp;
+	struct ext4_sb_info *sbi = EXT4_SB(sb);
+	struct inode *inode = sbi->s_buddy_cache;
+	struct page *page = NULL, *bitmap_page = NULL;
+
+	mb_debug("init group %lu\n", group);
+	blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize;
+	this_grp = ext4_get_group_info(sb, group);
+	/*
+	 * This ensures we don't add group
+	 * to this buddy cache via resize
+	 */
+	num_grp_locked =  ext4_mb_get_buddy_cache_lock(sb, group);
+	if (!EXT4_MB_GRP_NEED_INIT(this_grp)) {
+		/*
+		 * somebody initialized the group
+		 * return without doing anything
+		 */
+		ret = 0;
+		goto err;
+	}
+	/*
+	 * the buddy cache inode stores the block bitmap
+	 * and buddy information in consecutive blocks.
+	 * So for each group we need two blocks.
+	 */
+	block = group * 2;
+	pnum = block / blocks_per_page;
+	poff = block % blocks_per_page;
+	page = find_or_create_page(inode->i_mapping, pnum, GFP_NOFS);
+	if (page) {
+		BUG_ON(page->mapping != inode->i_mapping);
+		ret = ext4_mb_init_cache(page, NULL);
+		if (ret) {
+			unlock_page(page);
+			goto err;
+		}
+		unlock_page(page);
+	}
+	if (page == NULL || !PageUptodate(page)) {
+		ret = -EIO;
+		goto err;
+	}
+	mark_page_accessed(page);
+	bitmap_page = page;
+	bitmap = page_address(page) + (poff * sb->s_blocksize);
+
+	/* init buddy cache */
+	block++;
+	pnum = block / blocks_per_page;
+	poff = block % blocks_per_page;
+	page = find_or_create_page(inode->i_mapping, pnum, GFP_NOFS);
+	if (page == bitmap_page) {
+		/*
+		 * If both the bitmap and buddy are in
+		 * the same page we don't need to force
+		 * init the buddy
+		 */
+		unlock_page(page);
+	} else if (page) {
+		BUG_ON(page->mapping != inode->i_mapping);
+		ret = ext4_mb_init_cache(page, bitmap);
+		if (ret) {
+			unlock_page(page);
+			goto err;
+		}
+		unlock_page(page);
+	}
+	if (page == NULL || !PageUptodate(page)) {
+		ret = -EIO;
+		goto err;
+	}
+	mark_page_accessed(page);
+err:
+	ext4_mb_put_buddy_cache_lock(sb, group, num_grp_locked);
+	if (bitmap_page)
+		page_cache_release(bitmap_page);
+	if (page)
+		page_cache_release(page);
+	return ret;
+}
+
 static noinline_for_stack int
 ext4_mb_regular_allocator(struct ext4_allocation_context *ac)
 {
@@ -1777,7 +1968,7 @@ repeat:
 				group = 0;
 
 			/* quick check to skip empty groups */
-			grp = ext4_get_group_info(ac->ac_sb, group);
+			grp = ext4_get_group_info(sb, group);
 			if (grp->bb_free == 0)
 				continue;
 
@@ -1790,10 +1981,9 @@ repeat:
 				 * we need full data about the group
 				 * to make a good selection
 				 */
-				err = ext4_mb_load_buddy(sb, group, &e4b);
+				err = ext4_mb_init_group(sb, group);
 				if (err)
 					goto out;
-				ext4_mb_release_desc(&e4b);
 			}
 
 			/*
@@ -2302,6 +2492,7 @@ int ext4_mb_add_groupinfo(struct super_b
 	}
 
 	INIT_LIST_HEAD(&meta_group_info[i]->bb_prealloc_list);
+	init_rwsem(&meta_group_info[i]->alloc_sem);
 	meta_group_info[i]->bb_free_root.rb_node = NULL;;
 
 #ifdef DOUBLE_CHECK
@@ -2329,54 +2520,6 @@ exit_meta_group_info:
 } /* ext4_mb_add_groupinfo */
 
 /*
- * Add a group to the existing groups.
- * This function is used for online resize
- */
-int ext4_mb_add_more_groupinfo(struct super_block *sb, ext4_group_t group,
-			       struct ext4_group_desc *desc)
-{
-	struct ext4_sb_info *sbi = EXT4_SB(sb);
-	struct inode *inode = sbi->s_buddy_cache;
-	int blocks_per_page;
-	int block;
-	int pnum;
-	struct page *page;
-	int err;
-
-	/* Add group based on group descriptor*/
-	err = ext4_mb_add_groupinfo(sb, group, desc);
-	if (err)
-		return err;
-
-	/*
-	 * Cache pages containing dynamic mb_alloc datas (buddy and bitmap
-	 * datas) are set not up to date so that they will be re-initilaized
-	 * during the next call to ext4_mb_load_buddy
-	 */
-
-	/* Set buddy page as not up to date */
-	blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize;
-	block = group * 2;
-	pnum = block / blocks_per_page;
-	page = find_get_page(inode->i_mapping, pnum);
-	if (page != NULL) {
-		ClearPageUptodate(page);
-		page_cache_release(page);
-	}
-
-	/* Set bitmap page as not up to date */
-	block++;
-	pnum = block / blocks_per_page;
-	page = find_get_page(inode->i_mapping, pnum);
-	if (page != NULL) {
-		ClearPageUptodate(page);
-		page_cache_release(page);
-	}
-
-	return 0;
-}
-
-/*
  * Update an existing group.
  * This function is used for online resize
  */
@@ -4585,11 +4728,6 @@ do_more:
 	err = ext4_journal_get_write_access(handle, gd_bh);
 	if (err)
 		goto error_return;
-
-	err = ext4_mb_load_buddy(sb, block_group, &e4b);
-	if (err)
-		goto error_return;
-
 #ifdef AGGRESSIVE_CHECK
 	{
 		int i;
@@ -4603,6 +4741,8 @@ do_more:
 	/* We dirtied the bitmap block */
 	BUFFER_TRACE(bitmap_bh, "dirtied bitmap block");
 	err = ext4_journal_dirty_metadata(handle, bitmap_bh);
+	if (err)
+		goto error_return;
 
 	if (ac) {
 		ac->ac_b_ex.fe_group = block_group;
@@ -4611,6 +4751,9 @@ do_more:
 		ext4_mb_store_history(ac);
 	}
 
+	err = ext4_mb_load_buddy(sb, block_group, &e4b);
+	if (err)
+		goto error_return;
 	if (metadata) {
 		/* blocks being freed are metadata. these blocks shouldn't
 		 * be used until this transaction is committed */
--- a/fs/ext4/mballoc.h
+++ b/fs/ext4/mballoc.h
@@ -20,6 +20,7 @@
 #include <linux/version.h>
 #include <linux/blkdev.h>
 #include <linux/marker.h>
+#include <linux/mutex.h>
 #include "ext4_jbd2.h"
 #include "ext4.h"
 #include "group.h"
@@ -130,6 +131,7 @@ struct ext4_group_info {
 #ifdef DOUBLE_CHECK
 	void		*bb_bitmap;
 #endif
+	struct rw_semaphore alloc_sem;
 	unsigned short	bb_counters[];
 };
 
@@ -250,6 +252,7 @@ struct ext4_buddy {
 	struct super_block *bd_sb;
 	__u16 bd_blkbits;
 	ext4_group_t bd_group;
+	struct rw_semaphore *alloc_semp;
 };
 #define EXT4_MB_BITMAP(e4b)	((e4b)->bd_bitmap)
 #define EXT4_MB_BUDDY(e4b)	((e4b)->bd_buddy)
--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -747,6 +747,7 @@ int ext4_group_add(struct super_block *s
 	struct inode *inode = NULL;
 	handle_t *handle;
 	int gdb_off, gdb_num;
+	int num_grp_locked = 0;
 	int err, err2;
 
 	gdb_num = input->group / EXT4_DESC_PER_BLOCK(sb);
@@ -787,6 +788,7 @@ int ext4_group_add(struct super_block *s
 		}
 	}
 
+
 	if ((err = verify_group_input(sb, input)))
 		goto exit_put;
 
@@ -855,6 +857,7 @@ int ext4_group_add(struct super_block *s
          * using the new disk blocks.
          */
 
+	num_grp_locked = ext4_mb_get_buddy_cache_lock(sb, input->group);
 	/* Update group descriptor block for new group */
 	gdp = (struct ext4_group_desc *)((char *)primary->b_data +
 					 gdb_off * EXT4_DESC_SIZE(sb));
@@ -870,9 +873,11 @@ int ext4_group_add(struct super_block *s
 	 * We can allocate memory for mb_alloc based on the new group
 	 * descriptor
 	 */
-	err = ext4_mb_add_more_groupinfo(sb, input->group, gdp);
-	if (err)
+	err = ext4_mb_add_groupinfo(sb, input->group, gdp);
+	if (err) {
+		ext4_mb_put_buddy_cache_lock(sb, input->group, num_grp_locked);
 		goto exit_journal;
+	}
 
 	/*
 	 * Make the new blocks and inodes valid next.  We do this before
@@ -914,6 +919,7 @@ int ext4_group_add(struct super_block *s
 
 	/* Update the global fs size fields */
 	sbi->s_groups_count++;
+	ext4_mb_put_buddy_cache_lock(sb, input->group, num_grp_locked);
 
 	ext4_journal_dirty_metadata(handle, primary);
 
@@ -1081,45 +1087,6 @@ int ext4_group_extend(struct super_block
 	if ((err = ext4_journal_stop(handle)))
 		goto exit_put;
 
-	/*
-	 * Mark mballoc pages as not up to date so that they will be updated
-	 * next time they are loaded by ext4_mb_load_buddy.
-	 *
-	 * XXX Bad, Bad, BAD!!!  We should not be overloading the
-	 * Uptodate flag, particularly on thte bitmap bh, as way of
-	 * hinting to ext4_mb_load_buddy() that it needs to be
-	 * overloaded.  A user could take a LVM snapshot, then do an
-	 * on-line fsck, and clear the uptodate flag, and this would
-	 * not be a bug in userspace, but a bug in the kernel.  FIXME!!!
-	 */
-	{
-		struct ext4_sb_info *sbi = EXT4_SB(sb);
-		struct inode *inode = sbi->s_buddy_cache;
-		int blocks_per_page;
-		int block;
-		int pnum;
-		struct page *page;
-
-		/* Set buddy page as not up to date */
-		blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize;
-		block = group * 2;
-		pnum = block / blocks_per_page;
-		page = find_get_page(inode->i_mapping, pnum);
-		if (page != NULL) {
-			ClearPageUptodate(page);
-			page_cache_release(page);
-		}
-
-		/* Set bitmap page as not up to date */
-		block++;
-		pnum = block / blocks_per_page;
-		page = find_get_page(inode->i_mapping, pnum);
-		if (page != NULL) {
-			ClearPageUptodate(page);
-			page_cache_release(page);
-		}
-	}

[patch 24/39] ext4: cleanup mballoc header files

[Greg KH]

[-- Attachment #1: ext4-cleanup-mballoc-header-files.patch --]
[-- Type: text/plain, Size: 3810 bytes --]


2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

(cherry picked from commit c3a326a657562dab81acf05aee106dc1fe345eb4)

Move some of the forward declaration of the static functions
to mballoc.c where they are used. This enables us to include
mballoc.h in other .c files. Also correct the buddy cache
documentation.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/mballoc.c |   23 +++++++++++++++++++----
 fs/ext4/mballoc.h |   18 +-----------------
 2 files changed, 20 insertions(+), 21 deletions(-)

--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -100,7 +100,7 @@
  * inode as:
  *
  *  {                        page                        }
- *  [ group 0 buddy][ group 0 bitmap] [group 1][ group 1]...
+ *  [ group 0 bitmap][ group 0 buddy] [group 1][ group 1]...
  *
  *
  * one block each for bitmap and buddy information.  So for each group we
@@ -330,6 +330,16 @@
  *        object
  *
  */
+static struct kmem_cache *ext4_pspace_cachep;
+static struct kmem_cache *ext4_ac_cachep;
+static struct kmem_cache *ext4_free_ext_cachep;
+static void ext4_mb_generate_from_pa(struct super_block *sb, void *bitmap,
+					ext4_group_t group);
+static int ext4_mb_init_per_dev_proc(struct super_block *sb);
+static int ext4_mb_destroy_per_dev_proc(struct super_block *sb);
+static void release_blocks_on_commit(journal_t *journal, transaction_t *txn);
+
+
 
 static inline void *mb_correct_addr_and_bit(int *bit, void *addr)
 {
@@ -716,7 +726,7 @@ static void ext4_mb_generate_buddy(struc
  * stored in the inode as
  *
  * {                        page                        }
- * [ group 0 buddy][ group 0 bitmap] [group 1][ group 1]...
+ * [ group 0 bitmap][ group 0 buddy] [group 1][ group 1]...
  *
  *
  * one block each for bitmap and buddy information.
@@ -1320,8 +1330,13 @@ static void ext4_mb_use_best_found(struc
 	ac->ac_tail = ret & 0xffff;
 	ac->ac_buddy = ret >> 16;
 
-	/* XXXXXXX: SUCH A HORRIBLE **CK */
-	/*FIXME!! Why ? */
+	/*
+	 * take the page reference. We want the page to be pinned
+	 * so that we don't get a ext4_mb_init_cache_call for this
+	 * group until we update the bitmap. That would mean we
+	 * double allocate blocks. The reference is dropped
+	 * in ext4_mb_release_context
+	 */
 	ac->ac_bitmap_page = e4b->bd_bitmap_page;
 	get_page(ac->ac_bitmap_page);
 	ac->ac_buddy_page = e4b->bd_buddy_page;
--- a/fs/ext4/mballoc.h
+++ b/fs/ext4/mballoc.h
@@ -99,9 +99,6 @@
  */
 #define MB_DEFAULT_GROUP_PREALLOC	512
 
-static struct kmem_cache *ext4_pspace_cachep;
-static struct kmem_cache *ext4_ac_cachep;
-static struct kmem_cache *ext4_free_ext_cachep;
 
 struct ext4_free_data {
 	/* this links the free block information from group_info */
@@ -262,25 +259,12 @@ static inline void ext4_mb_store_history
 {
 	return;
 }
-#else
-static void ext4_mb_store_history(struct ext4_allocation_context *ac);
 #endif
 
 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
 
 struct buffer_head *read_block_bitmap(struct super_block *, ext4_group_t);
 
-static void ext4_mb_generate_from_pa(struct super_block *sb, void *bitmap,
-					ext4_group_t group);
-static void ext4_mb_return_to_preallocation(struct inode *inode,
-					struct ext4_buddy *e4b, sector_t block,
-					int count);
-static void ext4_mb_put_pa(struct ext4_allocation_context *,
-			struct super_block *, struct ext4_prealloc_space *pa);
-static int ext4_mb_init_per_dev_proc(struct super_block *sb);
-static int ext4_mb_destroy_per_dev_proc(struct super_block *sb);
-static void release_blocks_on_commit(journal_t *journal, transaction_t *txn);

[patch 25/39] ext4: dont use blocks freed but not yet committed in buddy cache init

[Greg KH]

[-- Attachment #1: ext4-don-t-use-blocks-freed-but-not-yet-committed-in-buddy-cache-init.patch --]
[-- Type: text/plain, Size: 6777 bytes --]


2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

(cherry picked from commit 7a2fcbf7f85737735fd44eb34b62315bccf6d6e4)

When we generate buddy cache (especially during resize) we need to
make sure we don't use the blocks freed but not yet comitted.  This
makes sure we have the right value of free blocks count in the group
info and also in the bitmap.  This also ensures the ordered mode
consistency

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/mballoc.c |   82 +++++++++++++++++++++++++++++++++++++++---------------
 1 file changed, 60 insertions(+), 22 deletions(-)

--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -335,6 +335,8 @@ static struct kmem_cache *ext4_ac_cachep
 static struct kmem_cache *ext4_free_ext_cachep;
 static void ext4_mb_generate_from_pa(struct super_block *sb, void *bitmap,
 					ext4_group_t group);
+static void ext4_mb_generate_from_freelist(struct super_block *sb, void *bitmap,
+						ext4_group_t group);
 static int ext4_mb_init_per_dev_proc(struct super_block *sb);
 static int ext4_mb_destroy_per_dev_proc(struct super_block *sb);
 static void release_blocks_on_commit(journal_t *journal, transaction_t *txn);
@@ -858,7 +860,9 @@ static int ext4_mb_init_cache(struct pag
 			/*
 			 * incore got set to the group block bitmap below
 			 */
+			ext4_lock_group(sb, group);
 			ext4_mb_generate_buddy(sb, data, incore, group);
+			ext4_unlock_group(sb, group);
 			incore = NULL;
 		} else {
 			/* this is block of bitmap */
@@ -872,6 +876,7 @@ static int ext4_mb_init_cache(struct pag
 
 			/* mark all preallocated blks used in in-core bitmap */
 			ext4_mb_generate_from_pa(sb, data, group);
+			ext4_mb_generate_from_freelist(sb, data, group);
 			ext4_unlock_group(sb, group);
 
 			/* set incore so that the buddy information can be
@@ -3469,6 +3474,32 @@ ext4_mb_use_preallocated(struct ext4_all
 }
 
 /*
+ * the function goes through all block freed in the group
+ * but not yet committed and marks them used in in-core bitmap.
+ * buddy must be generated from this bitmap
+ * Need to be called with ext4 group lock (ext4_lock_group)
+ */
+static void ext4_mb_generate_from_freelist(struct super_block *sb, void *bitmap,
+						ext4_group_t group)
+{
+	struct rb_node *n;
+	struct ext4_group_info *grp;
+	struct ext4_free_data *entry;
+
+	grp = ext4_get_group_info(sb, group);
+	n = rb_first(&(grp->bb_free_root));
+
+	while (n) {
+		entry = rb_entry(n, struct ext4_free_data, node);
+		mb_set_bits(sb_bgl_lock(EXT4_SB(sb), group),
+				bitmap, entry->start_blk,
+				entry->count);
+		n = rb_next(n);
+	}
+	return;
+}
+
+/*
  * the function goes through all preallocation in this group and marks them
  * used in in-core bitmap. buddy must be generated from this bitmap
  * Need to be called with ext4 group lock (ext4_lock_group)
@@ -4565,12 +4596,13 @@ static int can_merge(struct ext4_free_da
 
 static noinline_for_stack int
 ext4_mb_free_metadata(handle_t *handle, struct ext4_buddy *e4b,
-			  ext4_group_t group, ext4_grpblk_t block, int count)
+		      struct ext4_free_data *new_entry)
 {
+	ext4_grpblk_t block;
+	struct ext4_free_data *entry;
 	struct ext4_group_info *db = e4b->bd_info;
 	struct super_block *sb = e4b->bd_sb;
 	struct ext4_sb_info *sbi = EXT4_SB(sb);
-	struct ext4_free_data *entry, *new_entry;
 	struct rb_node **n = &db->bb_free_root.rb_node, *node;
 	struct rb_node *parent = NULL, *new_node;
 
@@ -4578,14 +4610,9 @@ ext4_mb_free_metadata(handle_t *handle, 
 	BUG_ON(e4b->bd_bitmap_page == NULL);
 	BUG_ON(e4b->bd_buddy_page == NULL);
 
-	new_entry  = kmem_cache_alloc(ext4_free_ext_cachep, GFP_NOFS);
-	new_entry->start_blk = block;
-	new_entry->group  = group;
-	new_entry->count = count;
-	new_entry->t_tid = handle->h_transaction->t_tid;
 	new_node = &new_entry->node;
+	block = new_entry->start_blk;
 
-	ext4_lock_group(sb, group);
 	if (!*n) {
 		/* first free block exent. We need to
 		   protect buddy cache from being freed,
@@ -4603,7 +4630,6 @@ ext4_mb_free_metadata(handle_t *handle, 
 		else if (block >= (entry->start_blk + entry->count))
 			n = &(*n)->rb_right;
 		else {
-			ext4_unlock_group(sb, group);
 			ext4_error(sb, __func__,
 			    "Double free of blocks %d (%d %d)\n",
 			    block, entry->start_blk, entry->count);
@@ -4645,7 +4671,6 @@ ext4_mb_free_metadata(handle_t *handle, 
 	spin_lock(&sbi->s_md_lock);
 	list_add(&new_entry->list, &handle->h_transaction->t_private_list);
 	spin_unlock(&sbi->s_md_lock);
-	ext4_unlock_group(sb, group);
 	return 0;
 }
 
@@ -4750,15 +4775,6 @@ do_more:
 			BUG_ON(!mb_test_bit(bit + i, bitmap_bh->b_data));
 	}
 #endif
-	mb_clear_bits(sb_bgl_lock(sbi, block_group), bitmap_bh->b_data,
-			bit, count);
-
-	/* We dirtied the bitmap block */
-	BUFFER_TRACE(bitmap_bh, "dirtied bitmap block");
-	err = ext4_journal_dirty_metadata(handle, bitmap_bh);
-	if (err)
-		goto error_return;
-
 	if (ac) {
 		ac->ac_b_ex.fe_group = block_group;
 		ac->ac_b_ex.fe_start = bit;
@@ -4770,11 +4786,29 @@ do_more:
 	if (err)
 		goto error_return;
 	if (metadata) {
-		/* blocks being freed are metadata. these blocks shouldn't
-		 * be used until this transaction is committed */
-		ext4_mb_free_metadata(handle, &e4b, block_group, bit, count);
+		struct ext4_free_data *new_entry;
+		/*
+		 * blocks being freed are metadata. these blocks shouldn't
+		 * be used until this transaction is committed
+		 */
+		new_entry  = kmem_cache_alloc(ext4_free_ext_cachep, GFP_NOFS);
+		new_entry->start_blk = bit;
+		new_entry->group  = block_group;
+		new_entry->count = count;
+		new_entry->t_tid = handle->h_transaction->t_tid;
+		ext4_lock_group(sb, block_group);
+		mb_clear_bits(sb_bgl_lock(sbi, block_group), bitmap_bh->b_data,
+				bit, count);
+		ext4_mb_free_metadata(handle, &e4b, new_entry);
+		ext4_unlock_group(sb, block_group);
 	} else {
 		ext4_lock_group(sb, block_group);
+		/* need to update group_info->bb_free and bitmap
+		 * with group lock held. generate_buddy look at
+		 * them with group lock_held
+		 */
+		mb_clear_bits(sb_bgl_lock(sbi, block_group), bitmap_bh->b_data,
+				bit, count);
 		mb_free_blocks(inode, &e4b, bit, count);
 		ext4_mb_return_to_preallocation(inode, &e4b, block, count);
 		ext4_unlock_group(sb, block_group);
@@ -4797,6 +4831,10 @@ do_more:
 
 	*freed += count;
 
+	/* We dirtied the bitmap block */
+	BUFFER_TRACE(bitmap_bh, "dirtied bitmap block");
+	err = ext4_journal_dirty_metadata(handle, bitmap_bh);
+
 	/* And the group descriptor block */
 	BUFFER_TRACE(gd_bh, "dirtied group descriptor block");
 	ret = ext4_journal_dirty_metadata(handle, gd_bh);

[patch 26/39] ext4: Fix race between read_block_bitmap() and mark_diskspace_used()

[Greg KH]

[-- Attachment #1: ext4-fix-race-between-read_block_bitmap-and-mark_diskspace_used.patch --]
[-- Type: text/plain, Size: 2534 bytes --]


2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

(cherry picked from commit e8134b27e351e813414da3b95aa8eac6d3908088)

We need to make sure we update the block bitmap and clear
EXT4_BG_BLOCK_UNINIT flag with sb_bgl_lock held, since
ext4_read_block_bitmap() looks at EXT4_BG_BLOCK_UNINIT to decide
whether to initialize the block bitmap each time it is called
(introduced by commit c806e68f), and this can race with block
allocations in ext4_mb_mark_diskspace_used().

ext4_read_block_bitmap does:

spin_lock(sb_bgl_lock(EXT4_SB(sb), block_group));
if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
	ext4_init_block_bitmap(sb, bh, block_group, desc);

Now on the block allocation side we do

mb_set_bits(sb_bgl_lock(sbi, ac->ac_b_ex.fe_group), bitmap_bh->b_data,
			ac->ac_b_ex.fe_start, ac->ac_b_ex.fe_len);
....
spin_lock(sb_bgl_lock(sbi, ac->ac_b_ex.fe_group));
if (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
	gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT);

ie on allocation we update the bitmap then we take the sb_bgl_lock
and clear the EXT4_BG_BLOCK_UNINIT flag. What can happen is a
parallel ext4_read_block_bitmap can zero out the bitmap in between
the above mb_set_bits and spin_lock(sb_bg_lock..)

The race results in below user visible errors
EXT4-fs error (device sdb1): ext4_mb_release_inode_pa: free 100, pa_free 105
EXT4-fs error (device sdb1): mb_free_blocks: double-free of inode 0's block ..

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/mballoc.c |   15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -1070,7 +1070,10 @@ static void mb_clear_bits(spinlock_t *lo
 			cur += 32;
 			continue;
 		}
-		mb_clear_bit_atomic(lock, cur, bm);
+		if (lock)
+			mb_clear_bit_atomic(lock, cur, bm);
+		else
+			mb_clear_bit(cur, bm);
 		cur++;
 	}
 }
@@ -1088,7 +1091,10 @@ static void mb_set_bits(spinlock_t *lock
 			cur += 32;
 			continue;
 		}
-		mb_set_bit_atomic(lock, cur, bm);
+		if (lock)
+			mb_set_bit_atomic(lock, cur, bm);
+		else
+			mb_set_bit(cur, bm);
 		cur++;
 	}
 }
@@ -3033,10 +3039,9 @@ ext4_mb_mark_diskspace_used(struct ext4_
 		}
 	}
 #endif
-	mb_set_bits(sb_bgl_lock(sbi, ac->ac_b_ex.fe_group), bitmap_bh->b_data,
-				ac->ac_b_ex.fe_start, ac->ac_b_ex.fe_len);

[patch 27/39] ext4: Fix the race between read_inode_bitmap() and ext4_new_inode()

[Greg KH]

[-- Attachment #1: ext4-fix-the-race-between-read_inode_bitmap-and-ext4_new_inode.patch --]
[-- Type: text/plain, Size: 7119 bytes --]


2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

(cherry picked from commit 393418676a7602e1d7d3f6e560159c65c8cbd50e)

We need to make sure we update the inode bitmap and clear
EXT4_BG_INODE_UNINIT flag with sb_bgl_lock held, since
ext4_read_inode_bitmap() looks at EXT4_BG_INODE_UNINIT to decide
whether to initialize the inode bitmap each time it is called.
(introduced by commit c806e68f.)

ext4_read_inode_bitmap does:

spin_lock(sb_bgl_lock(EXT4_SB(sb), block_group));
if (desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
	ext4_init_inode_bitmap(sb, bh, block_group, desc);

and ext4_new_inode does
if (!ext4_set_bit_atomic(sb_bgl_lock(sbi, group),
                   ino, inode_bitmap_bh->b_data))
		   ......
		   ...
spin_lock(sb_bgl_lock(sbi, group));

gdp->bg_flags &= cpu_to_le16(~EXT4_BG_INODE_UNINIT);
i.e., on allocation we update the bitmap then we take the sb_bgl_lock
and clear the EXT4_BG_INODE_UNINIT flag. What can happen is a
parallel ext4_read_inode_bitmap can zero out the bitmap in between
the above ext4_set_bit_atomic and spin_lock(sb_bg_lock..)

The race results in below user visible errors
EXT4-fs error (device sdb1): ext4_free_inode: bit already cleared for inode 168449
EXT4-fs warning (device sdb1): ext4_unlink: Deleting nonexistent file ...
EXT4-fs warning (device sdb1): ext4_rmdir: empty directory has too many links ...
ls: /mnt/tmp/f/p369/d3/d6/d39/db2/dee/d10f/d3f/l71: Stale NFS file handle

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/ialloc.c |  140 ++++++++++++++++++++++++++++++++-----------------------
 1 file changed, 83 insertions(+), 57 deletions(-)

--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -570,6 +570,77 @@ static int find_group_other(struct super
 }
 
 /*
+ * claim the inode from the inode bitmap. If the group
+ * is uninit we need to take the groups's sb_bgl_lock
+ * and clear the uninit flag. The inode bitmap update
+ * and group desc uninit flag clear should be done
+ * after holding sb_bgl_lock so that ext4_read_inode_bitmap
+ * doesn't race with the ext4_claim_inode
+ */
+static int ext4_claim_inode(struct super_block *sb,
+			struct buffer_head *inode_bitmap_bh,
+			unsigned long ino, ext4_group_t group, int mode)
+{
+	int free = 0, retval = 0;
+	struct ext4_sb_info *sbi = EXT4_SB(sb);
+	struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
+
+	spin_lock(sb_bgl_lock(sbi, group));
+	if (ext4_set_bit(ino, inode_bitmap_bh->b_data)) {
+		/* not a free inode */
+		retval = 1;
+		goto err_ret;
+	}
+	ino++;
+	if ((group == 0 && ino < EXT4_FIRST_INO(sb)) ||
+			ino > EXT4_INODES_PER_GROUP(sb)) {
+		spin_unlock(sb_bgl_lock(sbi, group));
+		ext4_error(sb, __func__,
+			   "reserved inode or inode > inodes count - "
+			   "block_group = %lu, inode=%lu", group,
+			   ino + group * EXT4_INODES_PER_GROUP(sb));
+		return 1;
+	}
+	/* If we didn't allocate from within the initialized part of the inode
+	 * table then we need to initialize up to this inode. */
+	if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
+
+		if (gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
+			gdp->bg_flags &= cpu_to_le16(~EXT4_BG_INODE_UNINIT);
+			/* When marking the block group with
+			 * ~EXT4_BG_INODE_UNINIT we don't want to depend
+			 * on the value of bg_itable_unused even though
+			 * mke2fs could have initialized the same for us.
+			 * Instead we calculated the value below
+			 */
+
+			free = 0;
+		} else {
+			free = EXT4_INODES_PER_GROUP(sb) -
+				le16_to_cpu(gdp->bg_itable_unused);
+		}
+
+		/*
+		 * Check the relative inode number against the last used
+		 * relative inode number in this group. if it is greater
+		 * we need to  update the bg_itable_unused count
+		 *
+		 */
+		if (ino > free)
+			gdp->bg_itable_unused =
+				cpu_to_le16(EXT4_INODES_PER_GROUP(sb) - ino);
+	}
+	le16_add_cpu(&gdp->bg_free_inodes_count, -1);
+	if (S_ISDIR(mode)) {
+		le16_add_cpu(&gdp->bg_used_dirs_count, 1);
+	}
+	gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp);
+err_ret:
+	spin_unlock(sb_bgl_lock(sbi, group));
+	return retval;
+}
+
+/*
  * There are two policies for allocating an inode.  If the new inode is
  * a directory, then a forward search is made for a block group with both
  * free space and a low directory-to-inode ratio; if that fails, then of
@@ -652,8 +723,12 @@ repeat_in_this_group:
 			if (err)
 				goto fail;
 
-			if (!ext4_set_bit_atomic(sb_bgl_lock(sbi, group),
-						ino, bitmap_bh->b_data)) {
+			BUFFER_TRACE(bh2, "get_write_access");
+			err = ext4_journal_get_write_access(handle, bh2);
+			if (err)
+				goto fail;
+			if (!ext4_claim_inode(sb, bitmap_bh,
+						ino, group, mode)) {
 				/* we won it */
 				BUFFER_TRACE(bitmap_bh,
 					"call ext4_journal_dirty_metadata");
@@ -661,10 +736,13 @@ repeat_in_this_group:
 								bitmap_bh);
 				if (err)
 					goto fail;
+				/* zero bit is inode number 1*/
+				ino++;
 				goto got;
 			}
 			/* we lost it */
 			jbd2_journal_release_buffer(handle, bitmap_bh);
+			jbd2_journal_release_buffer(handle, bh2);
 
 			if (++ino < EXT4_INODES_PER_GROUP(sb))
 				goto repeat_in_this_group;
@@ -684,21 +762,6 @@ repeat_in_this_group:
 	goto out;
 
 got:
-	ino++;
-	if ((group == 0 && ino < EXT4_FIRST_INO(sb)) ||
-	    ino > EXT4_INODES_PER_GROUP(sb)) {
-		ext4_error(sb, __func__,
-			   "reserved inode or inode > inodes count - "
-			   "block_group = %lu, inode=%lu", group,
-			   ino + group * EXT4_INODES_PER_GROUP(sb));
-		err = -EIO;
-		goto fail;
-	}
-
-	BUFFER_TRACE(bh2, "get_write_access");
-	err = ext4_journal_get_write_access(handle, bh2);
-	if (err) goto fail;
-
 	/* We may have to initialize the block bitmap if it isn't already */
 	if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM) &&
 	    gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
@@ -733,47 +796,10 @@ got:
 		if (err)
 			goto fail;
 	}
-
-	spin_lock(sb_bgl_lock(sbi, group));
-	/* If we didn't allocate from within the initialized part of the inode
-	 * table then we need to initialize up to this inode. */
-	if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
-		if (gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
-			gdp->bg_flags &= cpu_to_le16(~EXT4_BG_INODE_UNINIT);
-
-			/* When marking the block group with
-			 * ~EXT4_BG_INODE_UNINIT we don't want to depend
-			 * on the value of bg_itable_unused even though
-			 * mke2fs could have initialized the same for us.
-			 * Instead we calculated the value below
-			 */
-
-			free = 0;
-		} else {
-			free = EXT4_INODES_PER_GROUP(sb) -
-				le16_to_cpu(gdp->bg_itable_unused);
-		}
-
-		/*
-		 * Check the relative inode number against the last used
-		 * relative inode number in this group. if it is greater
-		 * we need to  update the bg_itable_unused count
-		 *
-		 */
-		if (ino > free)
-			gdp->bg_itable_unused =
-				cpu_to_le16(EXT4_INODES_PER_GROUP(sb) - ino);
-	}

[patch 28/39] jbd2: Add BH_JBDPrivateStart

[Greg KH]

[-- Attachment #1: jbd2-add-bh_jbdprivatestart.patch --]
[-- Type: text/plain, Size: 974 bytes --]


2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Mark Fasheh <mfasheh@suse.com>

(cherry picked from commit e97fcd95a4778a8caf1980c6c72fdf68185a0838)

Add this so that file systems using JBD2 can safely allocate unused b_state
bits.

In this case, we add it so that Ocfs2 can define a single bit for tracking
the validation state of a buffer.

Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 include/linux/jbd2.h |    1 +
 1 file changed, 1 insertion(+)

--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -329,6 +329,7 @@ enum jbd_state_bits {
 	BH_State,		/* Pins most journal_head state */
 	BH_JournalHead,		/* Pins bh->b_private and jh->b_bh */
 	BH_Unshadow,		/* Dummy bit, for BJ_Shadow wakeup filtering */
+	BH_JBDPrivateStart,	/* First bit available for private use by FS */
 };
 
 BUFFER_FNS(JBD, jbd)

[patch 29/39] ext4: Use new buffer_head flag to check uninit group bitmaps initialization

[Greg KH]

[-- Attachment #1: ext4-use-new-buffer_head-flag-to-check-uninit-group-bitmaps-initialization.patch --]
[-- Type: text/plain, Size: 5792 bytes --]


2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

(cherry picked from commit 2ccb5fb9f113dae969d1ae9b6c10e80fa34f8cd3)

For uninit block group, the on-disk bitmap is not initialized. That
implies we cannot depend on the uptodate flag on the bitmap
buffer_head to find bitmap validity.  Use a new buffer_head flag which
would be set after we properly initialize the bitmap.  This also
prevents (re-)initializing the uninit group bitmap every time we call
ext4_read_block_bitmap().

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/balloc.c  |   25 +++++++++++++++++++++++--
 fs/ext4/ext4.h    |   19 +++++++++++++++++++
 fs/ext4/ialloc.c  |   24 ++++++++++++++++++++++--
 fs/ext4/mballoc.c |   24 ++++++++++++++++++++++--
 4 files changed, 86 insertions(+), 6 deletions(-)

--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -320,20 +320,41 @@ ext4_read_block_bitmap(struct super_bloc
 			    block_group, bitmap_blk);
 		return NULL;
 	}
-	if (buffer_uptodate(bh) &&
-	    !(desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)))
+
+	if (bitmap_uptodate(bh))
 		return bh;
 
 	lock_buffer(bh);
+	if (bitmap_uptodate(bh)) {
+		unlock_buffer(bh);
+		return bh;
+	}
 	spin_lock(sb_bgl_lock(EXT4_SB(sb), block_group));
 	if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
 		ext4_init_block_bitmap(sb, bh, block_group, desc);
+		set_bitmap_uptodate(bh);
 		set_buffer_uptodate(bh);
 		unlock_buffer(bh);
 		spin_unlock(sb_bgl_lock(EXT4_SB(sb), block_group));
 		return bh;
 	}
 	spin_unlock(sb_bgl_lock(EXT4_SB(sb), block_group));
+	if (buffer_uptodate(bh)) {
+		/*
+		 * if not uninit if bh is uptodate,
+		 * bitmap is also uptodate
+		 */
+		set_bitmap_uptodate(bh);
+		unlock_buffer(bh);
+		return bh;
+	}
+	/*
+	 * submit the buffer_head for read. We can
+	 * safely mark the bitmap as uptodate now.
+	 * We do it here so the bitmap uptodate bit
+	 * get set with buffer lock held.
+	 */
+	set_bitmap_uptodate(bh);
 	if (bh_submit_read(bh) < 0) {
 		put_bh(bh);
 		ext4_error(sb, __func__,
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -19,6 +19,7 @@
 #include <linux/types.h>
 #include <linux/blkdev.h>
 #include <linux/magic.h>
+#include <linux/jbd2.h>
 #include "ext4_i.h"
 
 /*
@@ -1286,6 +1287,24 @@ extern int ext4_get_blocks_wrap(handle_t
 			sector_t block, unsigned long max_blocks,
 			struct buffer_head *bh, int create,
 			int extend_disksize, int flag);
+
+/*
+ * Add new method to test wether block and inode bitmaps are properly
+ * initialized. With uninit_bg reading the block from disk is not enough
+ * to mark the bitmap uptodate. We need to also zero-out the bitmap
+ */
+#define BH_BITMAP_UPTODATE BH_JBDPrivateStart
+
+static inline int bitmap_uptodate(struct buffer_head *bh)
+{
+	return (buffer_uptodate(bh) &&
+			test_bit(BH_BITMAP_UPTODATE, &(bh)->b_state));
+}
+static inline void set_bitmap_uptodate(struct buffer_head *bh)
+{
+	set_bit(BH_BITMAP_UPTODATE, &(bh)->b_state);
+}
+
 #endif	/* __KERNEL__ */
 
 #endif	/* _EXT4_H */
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -115,20 +115,40 @@ ext4_read_inode_bitmap(struct super_bloc
 			    block_group, bitmap_blk);
 		return NULL;
 	}
-	if (buffer_uptodate(bh) &&
-	    !(desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)))
+	if (bitmap_uptodate(bh))
 		return bh;
 
 	lock_buffer(bh);
+	if (bitmap_uptodate(bh)) {
+		unlock_buffer(bh);
+		return bh;
+	}
 	spin_lock(sb_bgl_lock(EXT4_SB(sb), block_group));
 	if (desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
 		ext4_init_inode_bitmap(sb, bh, block_group, desc);
+		set_bitmap_uptodate(bh);
 		set_buffer_uptodate(bh);
 		unlock_buffer(bh);
 		spin_unlock(sb_bgl_lock(EXT4_SB(sb), block_group));
 		return bh;
 	}
 	spin_unlock(sb_bgl_lock(EXT4_SB(sb), block_group));
+	if (buffer_uptodate(bh)) {
+		/*
+		 * if not uninit if bh is uptodate,
+		 * bitmap is also uptodate
+		 */
+		set_bitmap_uptodate(bh);
+		unlock_buffer(bh);
+		return bh;
+	}
+	/*
+	 * submit the buffer_head for read. We can
+	 * safely mark the bitmap as uptodate now.
+	 * We do it here so the bitmap uptodate bit
+	 * get set with buffer lock held.
+	 */
+	set_bitmap_uptodate(bh);
 	if (bh_submit_read(bh) < 0) {
 		put_bh(bh);
 		ext4_error(sb, __func__,
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -794,22 +794,42 @@ static int ext4_mb_init_cache(struct pag
 		if (bh[i] == NULL)
 			goto out;
 
-		if (buffer_uptodate(bh[i]) &&
-		    !(desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)))
+		if (bitmap_uptodate(bh[i]))
 			continue;
 
 		lock_buffer(bh[i]);
+		if (bitmap_uptodate(bh[i])) {
+			unlock_buffer(bh[i]);
+			continue;
+		}
 		spin_lock(sb_bgl_lock(EXT4_SB(sb), first_group + i));
 		if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
 			ext4_init_block_bitmap(sb, bh[i],
 						first_group + i, desc);
+			set_bitmap_uptodate(bh[i]);
 			set_buffer_uptodate(bh[i]);
 			unlock_buffer(bh[i]);
 			spin_unlock(sb_bgl_lock(EXT4_SB(sb), first_group + i));
 			continue;
 		}
 		spin_unlock(sb_bgl_lock(EXT4_SB(sb), first_group + i));
+		if (buffer_uptodate(bh[i])) {
+			/*
+			 * if not uninit if bh is uptodate,
+			 * bitmap is also uptodate
+			 */
+			set_bitmap_uptodate(bh[i]);
+			unlock_buffer(bh[i]);
+			continue;
+		}
 		get_bh(bh[i]);
+		/*
+		 * submit the buffer_head for read. We can
+		 * safely mark the bitmap as uptodate now.
+		 * We do it here so the bitmap uptodate bit
+		 * get set with buffer lock held.
+		 */
+		set_bitmap_uptodate(bh[i]);
 		bh[i]->b_end_io = end_buffer_read_sync;
 		submit_bh(READ, bh[i]);
 		mb_debug("read bitmap for group %lu\n", first_group + i);

[patch 30/39] ext4: mark the blocks/inode bitmap beyond end of group as used

[Greg KH]

[-- Attachment #1: ext4-mark-the-blocks-inode-bitmap-beyond-end-of-group-as-used.patch --]
[-- Type: text/plain, Size: 1935 bytes --]


2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

(cherry picked from commit 648f5879f5892dddd3ba71cd0d285599f40f2512)

We need to mark the block/inode bitmap beyond the end of the group
with '1'.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/ialloc.c  |    2 +-
 fs/ext4/mballoc.c |    4 ++--
 fs/ext4/resize.c  |    6 ++----
 3 files changed, 5 insertions(+), 7 deletions(-)

--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -84,7 +84,7 @@ unsigned ext4_init_inode_bitmap(struct s
 	}
 
 	memset(bh->b_data, 0, (EXT4_INODES_PER_GROUP(sb) + 7) / 8);
-	mark_bitmap_end(EXT4_INODES_PER_GROUP(sb), EXT4_BLOCKS_PER_GROUP(sb),
+	mark_bitmap_end(EXT4_INODES_PER_GROUP(sb), sb->s_blocksize * 8,
 			bh->b_data);
 
 	return EXT4_INODES_PER_GROUP(sb);
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -3036,8 +3036,8 @@ ext4_mb_mark_diskspace_used(struct ext4_
 	    in_range(block + len - 1, ext4_inode_table(sb, gdp),
 		     EXT4_SB(sb)->s_itb_per_group)) {
 		ext4_error(sb, __func__,
-			   "Allocating block in system zone - block = %llu",
-			   block);
+			   "Allocating block %llu in system zone of %d group\n",
+			   block, ac->ac_b_ex.fe_group);
 		/* File system mounted not to panic on error
 		 * Fix the bitmap and repeat the block allocation
 		 * We leak some of the blocks here.
--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -284,11 +284,9 @@ static int setup_new_group_blocks(struct
 	if ((err = extend_or_restart_transaction(handle, 2, bh)))
 		goto exit_bh;
 
-	mark_bitmap_end(input->blocks_count, EXT4_BLOCKS_PER_GROUP(sb),
-			bh->b_data);
+	mark_bitmap_end(input->blocks_count, sb->s_blocksize * 8, bh->b_data);
 	ext4_journal_dirty_metadata(handle, bh);
 	brelse(bh);

[patch 31/39] ext4: Dont allow new groups to be added during block allocation

[Greg KH]

[-- Attachment #1: ext4-don-t-allow-new-groups-to-be-added-during-block-allocation.patch --]
[-- Type: text/plain, Size: 2885 bytes --]


2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

(cherry picked from commit 8556e8f3b6c4c11601ce1e9ea8090a6d8bd5daae)

After we mark the blocks in the buddy cache as allocated,
we need to ensure that we don't reinit the buddy cache until
the block bitmap is updated.  This commit achieves this by holding
the group_info alloc_semaphore till ext4_mb_release_context

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/mballoc.c |   16 +++++++++++++---
 fs/ext4/mballoc.h |    5 +++++
 2 files changed, 18 insertions(+), 3 deletions(-)

--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -1052,7 +1052,8 @@ static void ext4_mb_release_desc(struct 
 	if (e4b->bd_buddy_page)
 		page_cache_release(e4b->bd_buddy_page);
 	/* Done with the buddy cache */
-	up_read(e4b->alloc_semp);
+	if (e4b->alloc_semp)
+		up_read(e4b->alloc_semp);
 }
 
 
@@ -1372,7 +1373,9 @@ static void ext4_mb_use_best_found(struc
 	get_page(ac->ac_bitmap_page);
 	ac->ac_buddy_page = e4b->bd_buddy_page;
 	get_page(ac->ac_buddy_page);
-
+	/* on allocation we use ac to track the held semaphore */
+	ac->alloc_semp =  e4b->alloc_semp;
+	e4b->alloc_semp = NULL;
 	/* store last allocated for subsequent stream allocation */
 	if ((ac->ac_flags & EXT4_MB_HINT_DATA)) {
 		spin_lock(&sbi->s_md_lock);
@@ -4286,6 +4289,7 @@ ext4_mb_initialize_context(struct ext4_a
 	ac->ac_pa = NULL;
 	ac->ac_bitmap_page = NULL;
 	ac->ac_buddy_page = NULL;
+	ac->alloc_semp = NULL;
 	ac->ac_lg = NULL;
 
 	/* we have to define context: we'll we work with a file or
@@ -4466,6 +4470,8 @@ static int ext4_mb_release_context(struc
 		}
 		ext4_mb_put_pa(ac, ac->ac_sb, pa);
 	}
+	if (ac->alloc_semp)
+		up_read(ac->alloc_semp);
 	if (ac->ac_bitmap_page)
 		page_cache_release(ac->ac_bitmap_page);
 	if (ac->ac_buddy_page)
@@ -4566,10 +4572,14 @@ repeat:
 				ac->ac_o_ex.fe_len < ac->ac_b_ex.fe_len)
 			ext4_mb_new_preallocation(ac);
 	}
-
 	if (likely(ac->ac_status == AC_STATUS_FOUND)) {
 		*errp = ext4_mb_mark_diskspace_used(ac, handle, reserv_blks);
 		if (*errp ==  -EAGAIN) {
+			/*
+			 * drop the reference that we took
+			 * in ext4_mb_use_best_found
+			 */
+			ext4_mb_release_context(ac);
 			ac->ac_b_ex.fe_group = 0;
 			ac->ac_b_ex.fe_start = 0;
 			ac->ac_b_ex.fe_len = 0;
--- a/fs/ext4/mballoc.h
+++ b/fs/ext4/mballoc.h
@@ -216,6 +216,11 @@ struct ext4_allocation_context {
 	__u8 ac_op;		/* operation, for history only */
 	struct page *ac_bitmap_page;
 	struct page *ac_buddy_page;
+	/*
+	 * pointer to the held semaphore upon successful
+	 * block allocation
+	 */
+	struct rw_semaphore *alloc_semp;
 	struct ext4_prealloc_space *ac_pa;
 	struct ext4_locality_group *ac_lg;
 };

[patch 32/39] ext4: Init the complete page while building buddy cache

[Greg KH]

[-- Attachment #1: ext4-init-the-complete-page-while-building-buddy-cache.patch --]
[-- Type: text/plain, Size: 1440 bytes --]


2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

(cherry picked from commit 29eaf024980e07cc01f31ae4ea5d68c917f4b7da)

We need to init the complete page during buddy cache init
by setting the contents to '1'.  Otherwise we can see the
following errors after doing an online resize of the
filesystem:

EXT4-fs error (device sdb1): ext4_mb_mark_diskspace_used:
	Allocating block 1040385 in system zone of 127 group

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/mballoc.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -846,6 +846,8 @@ static int ext4_mb_init_cache(struct pag
 
 	err = 0;
 	first_block = page->index * blocks_per_page;
+	/* init the page  */
+	memset(page_address(page), 0xff, PAGE_CACHE_SIZE);
 	for (i = 0; i < blocks_per_page; i++) {
 		int group;
 		struct ext4_group_info *grinfo;
@@ -872,7 +874,6 @@ static int ext4_mb_init_cache(struct pag
 			BUG_ON(incore == NULL);
 			mb_debug("put buddy for group %u in page %lu/%x\n",
 				group, page->index, i * blocksize);
-			memset(data, 0xff, blocksize);
 			grinfo = ext4_get_group_info(sb, group);
 			grinfo->bb_fragments = 0;
 			memset(grinfo->bb_counters, 0,

[patch 33/39] ext4: Fix s_dirty_blocks_counter if block allocation failed with nodelalloc

[Greg KH]

[-- Attachment #1: ext4-fix-s_dirty_blocks_counter-if-block-allocation-failed-with-nodelalloc.patch --]
[-- Type: text/plain, Size: 1390 bytes --]


2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

(cherry picked from commit 0087d9fb3f29f59e8d42c8b058376d80e5adde4c)

With nodelalloc option we need to update the dirty block counter on
block allocation failure. This is needed because we increment the
dirty block counter early in the block allocation phase. Without
the patch s_dirty_blocks_counter goes wrong so that filesystem's
free blocks decreases incorrectly.

Tested-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/mballoc.c |    9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -4538,7 +4538,7 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t
 	}
 	if (ar->len == 0) {
 		*errp = -EDQUOT;
-		return 0;
+		goto out3;
 	}
 	inquota = ar->len;
 
@@ -4611,6 +4611,13 @@ out2:
 out1:
 	if (ar->len < inquota)
 		DQUOT_FREE_BLOCK(ar->inode, inquota - ar->len);
+out3:
+	if (!ar->len) {
+		if (!EXT4_I(ar->inode)->i_delalloc_reserved_flag)
+			/* release all the reserved blocks if non delalloc */
+			percpu_counter_sub(&sbi->s_dirtyblocks_counter,
+						reserv_blks);
+	}
 
 	return block;
 }

[patch 34/39] ext4: Add sanity checks for the superblock before mounting the filesystem

[Greg KH]

[-- Attachment #1: ext4-add-sanity-checks-for-the-superblock-before-mounting-the-filesystem.patch --]
[-- Type: text/plain, Size: 2799 bytes --]

2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: "Theodore Ts'o" <tytso@mit.edu>

(cherry picked from commit 4ec110281379826c5cf6ed14735e47027c3c5765)

This avoids insane superblock configurations that could lead to kernel
oops due to null pointer derefences.

http://bugzilla.kernel.org/show_bug.cgi?id=12371

Thanks to David Maciejak at Fortinet's FortiGuard Global Security
Research Team who discovered this bug independently (but at
approximately the same time) as Thiemo Nagel, who submitted the patch.

Signed-off-by: Thiemo Nagel <thiemo.nagel@ph.tum.de>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/super.c |   30 ++++++++++++++++++++----------
 1 file changed, 20 insertions(+), 10 deletions(-)

--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1869,8 +1869,8 @@ static int ext4_fill_super(struct super_
 	char *cp;
 	int ret = -EINVAL;
 	int blocksize;
-	int db_count;
-	int i;
+	unsigned int db_count;
+	unsigned int i;
 	int needs_recovery, has_huge_files;
 	__le32 features;
 	__u64 blocks_count;
@@ -2153,20 +2153,30 @@ static int ext4_fill_super(struct super_
 	if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
 		goto cantfind_ext4;
 
-	/* ensure blocks_count calculation below doesn't sign-extend */
-	if (ext4_blocks_count(es) + EXT4_BLOCKS_PER_GROUP(sb) <
-	    le32_to_cpu(es->s_first_data_block) + 1) {
-		printk(KERN_WARNING "EXT4-fs: bad geometry: block count %llu, "
-		       "first data block %u, blocks per group %lu\n",
-			ext4_blocks_count(es),
-			le32_to_cpu(es->s_first_data_block),
-			EXT4_BLOCKS_PER_GROUP(sb));
+        /*
+         * It makes no sense for the first data block to be beyond the end
+         * of the filesystem.
+         */
+        if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
+                printk(KERN_WARNING "EXT4-fs: bad geometry: first data"
+		       "block %u is beyond end of filesystem (%llu)\n",
+		       le32_to_cpu(es->s_first_data_block),
+		       ext4_blocks_count(es));
 		goto failed_mount;
 	}
 	blocks_count = (ext4_blocks_count(es) -
 			le32_to_cpu(es->s_first_data_block) +
 			EXT4_BLOCKS_PER_GROUP(sb) - 1);
 	do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
+	if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
+		printk(KERN_WARNING "EXT4-fs: groups count too large: %u "
+		       "(block count %llu, first data block %u, "
+		       "blocks per group %lu)\n", sbi->s_groups_count,
+		       ext4_blocks_count(es),
+		       le32_to_cpu(es->s_first_data_block),
+		       EXT4_BLOCKS_PER_GROUP(sb));
+		goto failed_mount;
+	}
 	sbi->s_groups_count = blocks_count;
 	db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
 		   EXT4_DESC_PER_BLOCK(sb);

[patch 35/39] ext4: only use i_size_high for regular files

[Greg KH]

[-- Attachment #1: ext4-only-use-i_size_high-for-regular-files.patch --]
[-- Type: text/plain, Size: 2060 bytes --]


2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: "Theodore Ts'o" <tytso@mit.edu>

(cherry picked from commit 06a279d636734da32bb62dd2f7b0ade666f65d7c)

Directories are not allowed to be bigger than 2GB, so don't use
i_size_high for anything other than regular files.  E2fsck should
complain about these inodes, but the simplest thing to do for the
kernel is to only use i_size_high for regular files.

This prevents an intentially corrupted filesystem from causing the
kernel to burn a huge amount of CPU and issuing error messages such
as:

EXT4-fs warning (device loop0): ext4_block_to_path: block 135090028 > max

Thanks to David Maciejak from Fortinet's FortiGuard Global Security
Research Team for reporting this issue.

http://bugzilla.kernel.org/show_bug.cgi?id=12375

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/ext4.h  |    7 +++++--
 fs/ext4/inode.c |    4 ++--
 2 files changed, 7 insertions(+), 4 deletions(-)

--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1188,8 +1188,11 @@ static inline void ext4_r_blocks_count_s
 
 static inline loff_t ext4_isize(struct ext4_inode *raw_inode)
 {
-	return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
-		le32_to_cpu(raw_inode->i_size_lo);
+	if (S_ISREG(le16_to_cpu(raw_inode->i_mode)))
+		return ((loff_t)le32_to_cpu(raw_inode->i_size_high) << 32) |
+			le32_to_cpu(raw_inode->i_size_lo);
+	else
+		return (loff_t) le32_to_cpu(raw_inode->i_size_lo);
 }
 
 static inline void ext4_isize_set(struct ext4_inode *raw_inode, loff_t i_size)
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -351,9 +351,9 @@ static int ext4_block_to_path(struct ino
 		final = ptrs;
 	} else {
 		ext4_warning(inode->i_sb, "ext4_block_to_path",
-				"block %lu > max",
+				"block %lu > max in inode %lu",
 				i_block + direct_blocks +
-				indirect_blocks + double_blocks);
+				indirect_blocks + double_blocks, inode->i_ino);
 	}
 	if (boundary)
 		*boundary = final - 1 - (i_block & (ptrs - 1));

[patch 36/39] ext4: Add sanity check to make_indexed_dir

[Greg KH]

[-- Attachment #1: ext4-add-sanity-check-to-make_indexed_dir.patch --]
[-- Type: text/plain, Size: 2182 bytes --]

2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: "Theodore Ts'o" <tytso@mit.edu>

(cherry picked from commit e6b8bc09ba2075cd91fbffefcd2778b1a00bd76f)

Make sure the rec_len field in the '..' entry is sane, lest we overrun
the directory block and cause a kernel oops on a purposefully
corrupted filesystem.

Thanks to Sami Liedes for reporting this bug.

http://bugzilla.kernel.org/show_bug.cgi?id=12430

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/namei.c |   21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -1372,7 +1372,7 @@ static int make_indexed_dir(handle_t *ha
 	struct fake_dirent *fde;
 
 	blocksize =  dir->i_sb->s_blocksize;
-	dxtrace(printk(KERN_DEBUG "Creating index\n"));
+	dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino));
 	retval = ext4_journal_get_write_access(handle, bh);
 	if (retval) {
 		ext4_std_error(dir->i_sb, retval);
@@ -1381,6 +1381,20 @@ static int make_indexed_dir(handle_t *ha
 	}
 	root = (struct dx_root *) bh->b_data;
 
+	/* The 0th block becomes the root, move the dirents out */
+	fde = &root->dotdot;
+	de = (struct ext4_dir_entry_2 *)((char *)fde +
+		ext4_rec_len_from_disk(fde->rec_len));
+	if ((char *) de >= (((char *) root) + blocksize)) {
+		ext4_error(dir->i_sb, __func__,
+			   "invalid rec_len for '..' in inode %lu",
+			   dir->i_ino);
+		brelse(bh);
+		return -EIO;
+	}
+	len = ((char *) root) + blocksize - (char *) de;
+
+	/* Allocate new block for the 0th block's dirents */
 	bh2 = ext4_append(handle, dir, &block, &retval);
 	if (!(bh2)) {
 		brelse(bh);
@@ -1389,11 +1403,6 @@ static int make_indexed_dir(handle_t *ha
 	EXT4_I(dir)->i_flags |= EXT4_INDEX_FL;
 	data1 = bh2->b_data;
 
-	/* The 0th block becomes the root, move the dirents out */
-	fde = &root->dotdot;
-	de = (struct ext4_dir_entry_2 *)((char *)fde +
-		ext4_rec_len_from_disk(fde->rec_len));
-	len = ((char *) root) + blocksize - (char *) de;
 	memcpy (data1, de, len);
 	de = (struct ext4_dir_entry_2 *) data1;
 	top = data1 + len;

[patch 37/39] jbd2: On a __journal_expect() assertion failure printk "JBD2", not "EXT3-fs"

[Greg KH]

[-- Attachment #1: jbd2-on-a-__journal_expect-assertion-failure-printk-jbd2-not-ext3-fs.patch --]
[-- Type: text/plain, Size: 985 bytes --]

2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: "Theodore Ts'o" <tytso@mit.edu>

(cherry picked from commit 08ec8c3878cea0bf91f2ba3c0badf44b383752d0)

Otherwise it can be very confusing to find a "EXT3-fs: " failure in
the middle of EXT4-fs failures, and it makes it harder to track the
source of the failure.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 include/linux/jbd2.h |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -308,7 +308,8 @@ void buffer_assertion_failure(struct buf
 		int val = (expr);					     \
 		if (!val) {						     \
 			printk(KERN_ERR					     \
-				"EXT3-fs unexpected failure: %s;\n",# expr); \
+			       "JBD2 unexpected failure: %s: %s;\n",	     \
+			       __func__, #expr);			     \
 			printk(KERN_ERR why "\n");			     \
 		}							     \
 		val;							     \

[patch 38/39] ext4: Initialize the new group descriptor when resizing the filesystem

[Greg KH]

[-- Attachment #1: ext4-initialize-the-new-group-descriptor-when-resizing-the-filesystem.patch --]
[-- Type: text/plain, Size: 1367 bytes --]

2.6.28-stable review patch.  If anyone has any objections, please let us know.

------------------

From: "Theodore Ts'o" <tytso@mit.edu>
(cherry picked from commit fdff73f094e7220602cc3f8959c7230517976412)

Make sure all of the fields of the group descriptor are properly
initialized.  Previously, we allowed bg_flags field to be contain
random garbage, which could trigger non-deterministic behavior,
including a kernel OOPS.

http://bugzilla.kernel.org/show_bug.cgi?id=12433

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 fs/ext4/resize.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -860,11 +860,13 @@ int ext4_group_add(struct super_block *s
 	gdp = (struct ext4_group_desc *)((char *)primary->b_data +
 					 gdb_off * EXT4_DESC_SIZE(sb));
 
+	memset(gdp, 0, EXT4_DESC_SIZE(sb));
 	ext4_block_bitmap_set(sb, gdp, input->block_bitmap); /* LV FIXME */
 	ext4_inode_bitmap_set(sb, gdp, input->inode_bitmap); /* LV FIXME */
 	ext4_inode_table_set(sb, gdp, input->inode_table); /* LV FIXME */
 	gdp->bg_free_blocks_count = cpu_to_le16(input->free_blocks_count);
 	gdp->bg_free_inodes_count = cpu_to_le16(EXT4_INODES_PER_GROUP(sb));
+	gdp->bg_flags = cpu_to_le16(EXT4_BG_INODE_ZEROED);
 	gdp->bg_checksum = ext4_group_desc_csum(sbi, input->group, gdp);
 
 	/*