jbd2: clean up feature test macros with predicate functions

Create separate predicate functions to test/set/clear feature flags,
thereby replacing the wordy old macros.  Furthermore, clean out the
places where we open-coded feature tests.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

5 files changed, 91 insertions, 36 deletions

diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index 362e5f614450..36345fefa3ff 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -142,8 +142,7 @@ static int journal_submit_commit_record(journal_t *journal,
 	tmp->h_commit_sec = cpu_to_be64(now.tv_sec);
 	tmp->h_commit_nsec = cpu_to_be32(now.tv_nsec);
 
-	if (JBD2_HAS_COMPAT_FEATURE(journal,
-				    JBD2_FEATURE_COMPAT_CHECKSUM)) {
+	if (jbd2_has_feature_checksum(journal)) {
 		tmp->h_chksum_type 	= JBD2_CRC32_CHKSUM;
 		tmp->h_chksum_size 	= JBD2_CRC32_CHKSUM_SIZE;
 		tmp->h_chksum[0] 	= cpu_to_be32(crc32_sum);
@@ -157,8 +156,7 @@ static int journal_submit_commit_record(journal_t *journal,
 	bh->b_end_io = journal_end_buffer_io_sync;
 
 	if (journal->j_flags & JBD2_BARRIER &&
-	    !JBD2_HAS_INCOMPAT_FEATURE(journal,
-				       JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT))
+	    !jbd2_has_feature_async_commit(journal))
 		ret = submit_bh(WRITE_SYNC | WRITE_FLUSH_FUA, bh);
 	else
 		ret = submit_bh(WRITE_SYNC, bh);
@@ -317,7 +315,7 @@ static void write_tag_block(journal_t *j, journal_block_tag_t *tag,
 				   unsigned long long block)
 {
 	tag->t_blocknr = cpu_to_be32(block & (u32)~0);
-	if (JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_64BIT))
+	if (jbd2_has_feature_64bit(j))
 		tag->t_blocknr_high = cpu_to_be32((block >> 31) >> 1);
 }
 
@@ -356,7 +354,7 @@ static void jbd2_block_tag_csum_set(journal_t *j, journal_block_tag_t *tag,
 			     bh->b_size);
 	kunmap_atomic(addr);
 
-	if (JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V3))
+	if (jbd2_has_feature_csum3(j))
 		tag3->t_checksum = cpu_to_be32(csum32);
 	else
 		tag->t_checksum = cpu_to_be16(csum32);
@@ -730,8 +728,7 @@ start_journal_io:
 				/*
 				 * Compute checksum.
 				 */
-				if (JBD2_HAS_COMPAT_FEATURE(journal,
-					JBD2_FEATURE_COMPAT_CHECKSUM)) {
+				if (jbd2_has_feature_checksum(journal)) {
 					crc32_sum =
 					    jbd2_checksum_data(crc32_sum, bh);
 				}
@@ -797,8 +794,7 @@ start_journal_io:
 		blkdev_issue_flush(journal->j_fs_dev, GFP_NOFS, NULL);
 
 	/* Done it all: now write the commit record asynchronously. */
-	if (JBD2_HAS_INCOMPAT_FEATURE(journal,
-				      JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT)) {
+	if (jbd2_has_feature_async_commit(journal)) {
 		err = journal_submit_commit_record(journal, commit_transaction,
 						 &cbh, crc32_sum);
 		if (err)
@@ -889,8 +885,7 @@ start_journal_io:
 	commit_transaction->t_state = T_COMMIT_JFLUSH;
 	write_unlock(&journal->j_state_lock);
 
-	if (!JBD2_HAS_INCOMPAT_FEATURE(journal,
-				       JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT)) {
+	if (!jbd2_has_feature_async_commit(journal)) {
 		err = journal_submit_commit_record(journal, commit_transaction,
 						&cbh, crc32_sum);
 		if (err)
@@ -898,8 +893,7 @@ start_journal_io:
 	}
 	if (cbh)
 		err = journal_wait_on_commit_record(journal, cbh);
-	if (JBD2_HAS_INCOMPAT_FEATURE(journal,
-				      JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT) &&
+	if (jbd2_has_feature_async_commit(journal) &&
 	    journal->j_flags & JBD2_BARRIER) {
 		blkdev_issue_flush(journal->j_dev, GFP_NOFS, NULL);
 	}
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 474c1781c0ce..eb8a7546e8a4 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -1523,8 +1523,8 @@ static int journal_get_superblock(journal_t *journal)
 		goto out;
 	}
 
-	if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_CSUM_V2) &&
-	    JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_CSUM_V3)) {
+	if (jbd2_has_feature_csum2(journal) &&
+	    jbd2_has_feature_csum3(journal)) {
 		/* Can't have checksum v2 and v3 at the same time! */
 		printk(KERN_ERR "JBD2: Can't enable checksumming v2 and v3 "
 		       "at the same time!\n");
@@ -1532,7 +1532,7 @@ static int journal_get_superblock(journal_t *journal)
 	}
 
 	if (jbd2_journal_has_csum_v2or3_feature(journal) &&
-	    JBD2_HAS_COMPAT_FEATURE(journal, JBD2_FEATURE_COMPAT_CHECKSUM)) {
+	    jbd2_has_feature_checksum(journal)) {
 		/* Can't have checksum v1 and v2 on at the same time! */
 		printk(KERN_ERR "JBD2: Can't enable checksumming v1 and v2/3 "
 		       "at the same time!\n");
@@ -2198,15 +2198,15 @@ size_t journal_tag_bytes(journal_t *journal)
 {
 	size_t sz;
 
-	if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_CSUM_V3))
+	if (jbd2_has_feature_csum3(journal))
 		return sizeof(journal_block_tag3_t);
 
 	sz = sizeof(journal_block_tag_t);
 
-	if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_CSUM_V2))
+	if (jbd2_has_feature_csum2(journal))
 		sz += sizeof(__u16);
 
-	if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_64BIT))
+	if (jbd2_has_feature_64bit(journal))
 		return sz;
 	else
 		return sz - sizeof(__u32);
diff --git a/fs/jbd2/recovery.c b/fs/jbd2/recovery.c
index 5c836d78af3b..7f277e49fe88 100644
--- a/fs/jbd2/recovery.c
+++ b/fs/jbd2/recovery.c
@@ -342,7 +342,7 @@ static inline unsigned long long read_tag_block(journal_t *journal,
 						journal_block_tag_t *tag)
 {
 	unsigned long long block = be32_to_cpu(tag->t_blocknr);
-	if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_64BIT))
+	if (jbd2_has_feature_64bit(journal))
 		block |= (u64)be32_to_cpu(tag->t_blocknr_high) << 32;
 	return block;
 }
@@ -411,7 +411,7 @@ static int jbd2_block_tag_csum_verify(journal_t *j, journal_block_tag_t *tag,
 	csum32 = jbd2_chksum(j, j->j_csum_seed, (__u8 *)&seq, sizeof(seq));
 	csum32 = jbd2_chksum(j, csum32, buf, j->j_blocksize);
 
-	if (JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V3))
+	if (jbd2_has_feature_csum3(j))
 		return tag3->t_checksum == cpu_to_be32(csum32);
 	else
 		return tag->t_checksum == cpu_to_be16(csum32);
@@ -538,8 +538,7 @@ static int do_one_pass(journal_t *journal,
 			 * just skip over the blocks it describes. */
 			if (pass != PASS_REPLAY) {
 				if (pass == PASS_SCAN &&
-				    JBD2_HAS_COMPAT_FEATURE(journal,
-					    JBD2_FEATURE_COMPAT_CHECKSUM) &&
+				    jbd2_has_feature_checksum(journal) &&
 				    !info->end_transaction) {
 					if (calc_chksums(journal, bh,
 							&next_log_block,
@@ -694,8 +693,7 @@ static int do_one_pass(journal_t *journal,
 			 * much to do other than move on to the next sequence
 			 * number. */
 			if (pass == PASS_SCAN &&
-			    JBD2_HAS_COMPAT_FEATURE(journal,
-				    JBD2_FEATURE_COMPAT_CHECKSUM)) {
+			    jbd2_has_feature_checksum(journal)) {
 				int chksum_err, chksum_seen;
 				struct commit_header *cbh =
 					(struct commit_header *)bh->b_data;
@@ -735,8 +733,7 @@ static int do_one_pass(journal_t *journal,
 				if (chksum_err) {
 					info->end_transaction = next_commit_ID;
 
-					if (!JBD2_HAS_INCOMPAT_FEATURE(journal,
-					   JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT)){
+					if (!jbd2_has_feature_async_commit(journal)) {
 						journal->j_failed_commit =
 							next_commit_ID;
 						brelse(bh);
@@ -750,8 +747,7 @@ static int do_one_pass(journal_t *journal,
 							   bh->b_data)) {
 				info->end_transaction = next_commit_ID;
 
-				if (!JBD2_HAS_INCOMPAT_FEATURE(journal,
-				     JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT)) {
+				if (!jbd2_has_feature_async_commit(journal)) {
 					journal->j_failed_commit =
 						next_commit_ID;
 					brelse(bh);
@@ -859,7 +855,7 @@ static int scan_revoke_records(journal_t *journal, struct buffer_head *bh,
 		return -EINVAL;
 	max = rcount;
 
-	if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_64BIT))
+	if (jbd2_has_feature_64bit(journal))
 		record_len = 8;
 
 	while (offset + record_len <= max) {
diff --git a/fs/jbd2/revoke.c b/fs/jbd2/revoke.c
index 0abf2e7f725b..705ae577882b 100644
--- a/fs/jbd2/revoke.c
+++ b/fs/jbd2/revoke.c
@@ -589,7 +589,7 @@ static void write_one_revoke_record(journal_t *journal,
 	if (jbd2_journal_has_csum_v2or3(journal))
 		csum_size = sizeof(struct jbd2_journal_revoke_tail);
 
-	if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_64BIT))
+	if (jbd2_has_feature_64bit(journal))
 		sz = 8;
 	else
 		sz = 4;
@@ -619,7 +619,7 @@ static void write_one_revoke_record(journal_t *journal,
 		*descriptorp = descriptor;
 	}
 
-	if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_64BIT))
+	if (jbd2_has_feature_64bit(journal))
 		* ((__be64 *)(&descriptor->b_data[offset])) =
 			cpu_to_be64(record->blocknr);
 	else
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index f2a4b07a6ce6..b5ca2314cace 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -278,6 +278,7 @@ typedef struct journal_superblock_s
 /* 0x0400 */
 } journal_superblock_t;
 
+/* Use the jbd2_{has,set,clear}_feature_* helpers; these will be removed */
 #define JBD2_HAS_COMPAT_FEATURE(j,mask)					\
 	((j)->j_format_version >= 2 &&					\
 	 ((j)->j_superblock->s_feature_compat & cpu_to_be32((mask))))
@@ -288,7 +289,7 @@ typedef struct journal_superblock_s
 	((j)->j_format_version >= 2 &&					\
 	 ((j)->j_superblock->s_feature_incompat & cpu_to_be32((mask))))
 
-#define JBD2_FEATURE_COMPAT_CHECKSUM	0x00000001
+#define JBD2_FEATURE_COMPAT_CHECKSUM		0x00000001
 
 #define JBD2_FEATURE_INCOMPAT_REVOKE		0x00000001
 #define JBD2_FEATURE_INCOMPAT_64BIT		0x00000002
@@ -296,6 +297,8 @@ typedef struct journal_superblock_s
 #define JBD2_FEATURE_INCOMPAT_CSUM_V2		0x00000008
 #define JBD2_FEATURE_INCOMPAT_CSUM_V3		0x00000010
 
+/* See "journal feature predicate functions" below */
+
 /* Features known to this kernel version: */
 #define JBD2_KNOWN_COMPAT_FEATURES	JBD2_FEATURE_COMPAT_CHECKSUM
 #define JBD2_KNOWN_ROCOMPAT_FEATURES	0
@@ -1034,6 +1037,69 @@ struct journal_s
 	__u32 j_csum_seed;
 };
 
+/* journal feature predicate functions */
+#define JBD2_FEATURE_COMPAT_FUNCS(name, flagname) \
+static inline bool jbd2_has_feature_##name(journal_t *j) \
+{ \
+	return ((j)->j_format_version >= 2 && \
+		((j)->j_superblock->s_feature_compat & \
+		 cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname)) != 0); \
+} \
+static inline void jbd2_set_feature_##name(journal_t *j) \
+{ \
+	(j)->j_superblock->s_feature_compat |= \
+		cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \
+} \
+static inline void jbd2_clear_feature_##name(journal_t *j) \
+{ \
+	(j)->j_superblock->s_feature_compat &= \
+		~cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \
+}
+
+#define JBD2_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
+static inline bool jbd2_has_feature_##name(journal_t *j) \
+{ \
+	return ((j)->j_format_version >= 2 && \
+		((j)->j_superblock->s_feature_ro_compat & \
+		 cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname)) != 0); \
+} \
+static inline void jbd2_set_feature_##name(journal_t *j) \
+{ \
+	(j)->j_superblock->s_feature_ro_compat |= \
+		cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \
+} \
+static inline void jbd2_clear_feature_##name(journal_t *j) \
+{ \
+	(j)->j_superblock->s_feature_ro_compat &= \
+		~cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \
+}
+
+#define JBD2_FEATURE_INCOMPAT_FUNCS(name, flagname) \
+static inline bool jbd2_has_feature_##name(journal_t *j) \
+{ \
+	return ((j)->j_format_version >= 2 && \
+		((j)->j_superblock->s_feature_incompat & \
+		 cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname)) != 0); \
+} \
+static inline void jbd2_set_feature_##name(journal_t *j) \
+{ \
+	(j)->j_superblock->s_feature_incompat |= \
+		cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \
+} \
+static inline void jbd2_clear_feature_##name(journal_t *j) \
+{ \
+	(j)->j_superblock->s_feature_incompat &= \
+		~cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \
+}
+
+JBD2_FEATURE_COMPAT_FUNCS(checksum,		CHECKSUM)
+
+JBD2_FEATURE_INCOMPAT_FUNCS(revoke,		REVOKE)
+JBD2_FEATURE_INCOMPAT_FUNCS(64bit,		64BIT)
+JBD2_FEATURE_INCOMPAT_FUNCS(async_commit,	ASYNC_COMMIT)
+JBD2_FEATURE_INCOMPAT_FUNCS(csum2,		CSUM_V2)
+JBD2_FEATURE_INCOMPAT_FUNCS(csum3,		CSUM_V3)
+
 /*
  * Journal flag definitions
  */
@@ -1340,8 +1406,7 @@ extern size_t journal_tag_bytes(journal_t *journal);
 
 static inline bool jbd2_journal_has_csum_v2or3_feature(journal_t *j)
 {
-	return JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2) ||
-	       JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V3);
+	return jbd2_has_feature_csum2(j) || jbd2_has_feature_csum3(j);
 }
 
 static inline int jbd2_journal_has_csum_v2or3(journal_t *journal)