Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull Ext4 updates from Theodore Ts'o:
 "The major new feature added in this update is Darrick J Wong's
  metadata checksum feature, which adds crc32 checksums to ext4's
  metadata fields.

  There is also the usual set of cleanups and bug fixes."

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (44 commits)
  ext4: hole-punch use truncate_pagecache_range
  jbd2: use kmem_cache_zalloc wrapper instead of flag
  ext4: remove mb_groups before tearing down the buddy_cache
  ext4: add ext4_mb_unload_buddy in the error path
  ext4: don't trash state flags in EXT4_IOC_SETFLAGS
  ext4: let getattr report the right blocks in delalloc+bigalloc
  ext4: add missing save_error_info() to ext4_error()
  ext4: add debugging trigger for ext4_error()
  ext4: protect group inode free counting with group lock
  ext4: use consistent ssize_t type in ext4_file_write()
  ext4: fix format flag in ext4_ext_binsearch_idx()
  ext4: cleanup in ext4_discard_allocated_blocks()
  ext4: return ENOMEM when mounts fail due to lack of memory
  ext4: remove redundundant "(char *) bh->b_data" casts
  ext4: disallow hard-linked directory in ext4_lookup
  ext4: fix potential integer overflow in alloc_flex_gd()
  ext4: remove needs_recovery in ext4_mb_init()
  ext4: force ro mount if ext4_setup_super() fails
  ext4: fix potential NULL dereference in ext4_free_inodes_counts()
  ext4/jbd2: add metadata checksumming to the list of supported features
  ...

1 files changed, 67 insertions, 3 deletions

diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index 840f70f50792..216f4299f65e 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -85,6 +85,24 @@ nope:
 	__brelse(bh);
 }
 
+static void jbd2_commit_block_csum_set(journal_t *j,
+				       struct journal_head *descriptor)
+{
+	struct commit_header *h;
+	__u32 csum;
+
+	if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2))
+		return;
+
+	h = (struct commit_header *)(jh2bh(descriptor)->b_data);
+	h->h_chksum_type = 0;
+	h->h_chksum_size = 0;
+	h->h_chksum[0] = 0;
+	csum = jbd2_chksum(j, j->j_csum_seed, jh2bh(descriptor)->b_data,
+			   j->j_blocksize);
+	h->h_chksum[0] = cpu_to_be32(csum);
+}
+
 /*
  * Done it all: now submit the commit record.  We should have
  * cleaned up our previous buffers by now, so if we are in abort
@@ -128,6 +146,7 @@ static int journal_submit_commit_record(journal_t *journal,
 		tmp->h_chksum_size 	= JBD2_CRC32_CHKSUM_SIZE;
 		tmp->h_chksum[0] 	= cpu_to_be32(crc32_sum);
 	}
+	jbd2_commit_block_csum_set(journal, descriptor);
 
 	JBUFFER_TRACE(descriptor, "submit commit block");
 	lock_buffer(bh);
@@ -301,6 +320,44 @@ static void write_tag_block(int tag_bytes, journal_block_tag_t *tag,
 		tag->t_blocknr_high = cpu_to_be32((block >> 31) >> 1);
 }
 
+static void jbd2_descr_block_csum_set(journal_t *j,
+				      struct journal_head *descriptor)
+{
+	struct jbd2_journal_block_tail *tail;
+	__u32 csum;
+
+	if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2))
+		return;
+
+	tail = (struct jbd2_journal_block_tail *)
+			(jh2bh(descriptor)->b_data + j->j_blocksize -
+			sizeof(struct jbd2_journal_block_tail));
+	tail->t_checksum = 0;
+	csum = jbd2_chksum(j, j->j_csum_seed, jh2bh(descriptor)->b_data,
+			   j->j_blocksize);
+	tail->t_checksum = cpu_to_be32(csum);
+}
+
+static void jbd2_block_tag_csum_set(journal_t *j, journal_block_tag_t *tag,
+				    struct buffer_head *bh, __u32 sequence)
+{
+	struct page *page = bh->b_page;
+	__u8 *addr;
+	__u32 csum;
+
+	if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2))
+		return;
+
+	sequence = cpu_to_be32(sequence);
+	addr = kmap_atomic(page, KM_USER0);
+	csum = jbd2_chksum(j, j->j_csum_seed, (__u8 *)&sequence,
+			  sizeof(sequence));
+	csum = jbd2_chksum(j, csum, addr + offset_in_page(bh->b_data),
+			  bh->b_size);
+	kunmap_atomic(addr, KM_USER0);
+
+	tag->t_checksum = cpu_to_be32(csum);
+}
 /*
  * jbd2_journal_commit_transaction
  *
@@ -334,6 +391,10 @@ void jbd2_journal_commit_transaction(journal_t *journal)
 	unsigned long first_block;
 	tid_t first_tid;
 	int update_tail;
+	int csum_size = 0;
+
+	if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_CSUM_V2))
+		csum_size = sizeof(struct jbd2_journal_block_tail);
 
 	/*
 	 * First job: lock down the current transaction and wait for
@@ -627,7 +688,9 @@ void jbd2_journal_commit_transaction(journal_t *journal)
 
 		tag = (journal_block_tag_t *) tagp;
 		write_tag_block(tag_bytes, tag, jh2bh(jh)->b_blocknr);
-		tag->t_flags = cpu_to_be32(tag_flag);
+		tag->t_flags = cpu_to_be16(tag_flag);
+		jbd2_block_tag_csum_set(journal, tag, jh2bh(new_jh),
+					commit_transaction->t_tid);
 		tagp += tag_bytes;
 		space_left -= tag_bytes;
 
@@ -643,7 +706,7 @@ void jbd2_journal_commit_transaction(journal_t *journal)
 
 		if (bufs == journal->j_wbufsize ||
 		    commit_transaction->t_buffers == NULL ||
-		    space_left < tag_bytes + 16) {
+		    space_left < tag_bytes + 16 + csum_size) {
 
 			jbd_debug(4, "JBD2: Submit %d IOs\n", bufs);
 
@@ -651,8 +714,9 @@ void jbd2_journal_commit_transaction(journal_t *journal)
                            submitting the IOs.  "tag" still points to
                            the last tag we set up. */
 
-			tag->t_flags |= cpu_to_be32(JBD2_FLAG_LAST_TAG);
+			tag->t_flags |= cpu_to_be16(JBD2_FLAG_LAST_TAG);
 
+			jbd2_descr_block_csum_set(journal, descriptor);
 start_journal_io:
 			for (i = 0; i < bufs; i++) {
 				struct buffer_head *bh = wbuf[i];