Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kern…

…el/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "Various bug fixes and cleanups for ext4; no new features this cycle"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (29 commits)
  ext4: remove unnecessary wbc parameter from ext4_bio_write_page
  ext4: avoid s_mb_prefetch to be zero in individual scenarios
  ext4: defer saving error info from atomic context
  ext4: simplify ext4 error translation
  ext4: move functions in super.c
  ext4: make ext4_abort() use __ext4_error()
  ext4: standardize error message in ext4_protect_reserved_inode()
  ext4: remove redundant sb checksum recomputation
  ext4: don't remount read-only with errors=continue on reboot
  ext4: fix deadlock with fs freezing and EA inodes
  jbd2: add a helper to find out number of fast commit blocks
  ext4: make fast_commit.h byte identical with e2fsprogs/fast_commit.h
  ext4: fix fall-through warnings for Clang
  ext4: add docs about fast commit idempotence
  ext4: remove the unused EXT4_CURRENT_REV macro
  ext4: fix an IS_ERR() vs NULL check
  ext4: check for invalid block size early when mounting a file system
  ext4: fix a memory leak of ext4_free_data
  ext4: delete nonsensical (commented-out) code inside ext4_xattr_block_set()
  ext4: update ext4_data_block_valid related comments
  ...

Documentation/filesystems/ext4/journal.rst

@@ -681,3 +681,53 @@ Here is the list of supported tags and their meanings:
      - Stores the TID of the commit, CRC of the fast commit of which this tag
        represents the end of
 
+Fast Commit Replay Idempotence
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Fast commits tags are idempotent in nature provided the recovery code follows
+certain rules. The guiding principle that the commit path follows while
+committing is that it stores the result of a particular operation instead of
+storing the procedure.
+
+Let's consider this rename operation: 'mv /a /b'. Let's assume dirent '/a'
+was associated with inode 10. During fast commit, instead of storing this
+operation as a procedure "rename a to b", we store the resulting file system
+state as a "series" of outcomes:
+
+- Link dirent b to inode 10
+- Unlink dirent a
+- Inode 10 with valid refcount
+
+Now when recovery code runs, it needs "enforce" this state on the file
+system. This is what guarantees idempotence of fast commit replay.
+
+Let's take an example of a procedure that is not idempotent and see how fast
+commits make it idempotent. Consider following sequence of operations:
+
+1) rm A
+2) mv B A
+3) read A
+
+If we store this sequence of operations as is then the replay is not idempotent.
+Let's say while in replay, we crash after (2). During the second replay,
+file A (which was actually created as a result of "mv B A" operation) would get
+deleted. Thus, file named A would be absent when we try to read A. So, this
+sequence of operations is not idempotent. However, as mentioned above, instead
+of storing the procedure fast commits store the outcome of each procedure. Thus
+the fast commit log for above procedure would be as follows:
+
+(Let's assume dirent A was linked to inode 10 and dirent B was linked to
+inode 11 before the replay)
+
+1) Unlink A
+2) Link A to inode 11
+3) Unlink B
+4) Inode 11
+
+If we crash after (3) we will have file A linked to inode 11. During the second
+replay, we will remove file A (inode 11). But we will create it back and make
+it point to inode 11. We won't find B, so we'll just skip that step. At this
+point, the refcount for inode 11 is not reliable, but that gets fixed by the
+replay of last inode 11 tag. Thus, by converting a non-idempotent procedure
+into a series of idempotent outcomes, fast commits ensured idempotence during
+the replay.

fs/ext4/balloc.c

@@ -185,7 +185,7 @@ static int ext4_init_block_bitmap(struct super_block *sb,
 	struct ext4_sb_info *sbi = EXT4_SB(sb);
 	ext4_fsblk_t start, tmp;
 
-	J_ASSERT_BH(bh, buffer_locked(bh));
+	ASSERT(buffer_locked(bh));
 
 	/* If checksum is bad mark all blocks used to prevent allocation
 	 * essentially implementing a per-group read-only flag. */

fs/ext4/block_validity.c

@@ -176,12 +176,10 @@ static int ext4_protect_reserved_inode(struct super_block *sb,
 			err = add_system_zone(system_blks, map.m_pblk, n, ino);
 			if (err < 0) {
 				if (err == -EFSCORRUPTED) {
-					__ext4_error(sb, __func__, __LINE__,
-						     -err, map.m_pblk,
-						     "blocks %llu-%llu from inode %u overlap system zone",
-						     map.m_pblk,
-						     map.m_pblk + map.m_len - 1,
-						     ino);
+					EXT4_ERROR_INODE_ERR(inode, -err,
+						"blocks %llu-%llu from inode overlap system zone",
+						map.m_pblk,
+						map.m_pblk + map.m_len - 1);
 				}
 				break;
 			}
@@ -206,7 +204,7 @@ static void ext4_destroy_system_zone(struct rcu_head *rcu)
  *
  * The update of system_blks pointer in this function is protected by
  * sb->s_umount semaphore. However we have to be careful as we can be
- * racing with ext4_data_block_valid() calls reading system_blks rbtree
+ * racing with ext4_inode_block_valid() calls reading system_blks rbtree
  * protected only by RCU. That's why we first build the rbtree and then
  * swap it in place.
  */
@@ -258,7 +256,7 @@ int ext4_setup_system_zone(struct super_block *sb)
 
 	/*
 	 * System blks rbtree complete, announce it once to prevent racing
-	 * with ext4_data_block_valid() accessing the rbtree at the same
+	 * with ext4_inode_block_valid() accessing the rbtree at the same
 	 * time.
 	 */
 	rcu_assign_pointer(sbi->s_system_blks, system_blks);
@@ -278,7 +276,7 @@ int ext4_setup_system_zone(struct super_block *sb)
  *
  * The update of system_blks pointer in this function is protected by
  * sb->s_umount semaphore. However we have to be careful as we can be
- * racing with ext4_data_block_valid() calls reading system_blks rbtree
+ * racing with ext4_inode_block_valid() calls reading system_blks rbtree
  * protected only by RCU. So we first clear the system_blks pointer and
  * then free the rbtree only after RCU grace period expires.
  */

fs/ext4/ext4.h

@@ -98,6 +98,16 @@
 #define ext_debug(ino, fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
 #endif
 
+#define ASSERT(assert)						\
+do {									\
+	if (unlikely(!(assert))) {					\
+		printk(KERN_EMERG					\
+		       "Assertion failure in %s() at %s:%d: '%s'\n",	\
+		       __func__, __FILE__, __LINE__, #assert);		\
+		BUG();							\
+	}								\
+} while (0)
+
 /* data type for block offset of block group */
 typedef int ext4_grpblk_t;
 
@@ -1619,6 +1629,27 @@ struct ext4_sb_info {
 	errseq_t s_bdev_wb_err;
 	spinlock_t s_bdev_wb_lock;
 
+	/* Information about errors that happened during this mount */
+	spinlock_t s_error_lock;
+	int s_add_error_count;
+	int s_first_error_code;
+	__u32 s_first_error_line;
+	__u32 s_first_error_ino;
+	__u64 s_first_error_block;
+	const char *s_first_error_func;
+	time64_t s_first_error_time;
+	int s_last_error_code;
+	__u32 s_last_error_line;
+	__u32 s_last_error_ino;
+	__u64 s_last_error_block;
+	const char *s_last_error_func;
+	time64_t s_last_error_time;
+	/*
+	 * If we are in a context where we cannot update error information in
+	 * the on-disk superblock, we queue this work to do it.
+	 */
+	struct work_struct s_error_work;
+
 	/* Ext4 fast commit stuff */
 	atomic_t s_fc_subtid;
 	atomic_t s_fc_ineligible_updates;
@@ -1858,7 +1889,6 @@ static inline bool ext4_verity_in_progress(struct inode *inode)
 #define EXT4_GOOD_OLD_REV	0	/* The good old (original) format */
 #define EXT4_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */
 
-#define EXT4_CURRENT_REV	EXT4_GOOD_OLD_REV
 #define EXT4_MAX_SUPP_REV	EXT4_DYNAMIC_REV
 
 #define EXT4_GOOD_OLD_INODE_SIZE 128
@@ -2952,9 +2982,9 @@ extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
 					     ext4_group_t block_group,
 					     unsigned int flags);
 
-extern __printf(6, 7)
-void __ext4_error(struct super_block *, const char *, unsigned int, int, __u64,
-		  const char *, ...);
+extern __printf(7, 8)
+void __ext4_error(struct super_block *, const char *, unsigned int, bool,
+		  int, __u64, const char *, ...);
 extern __printf(6, 7)
 void __ext4_error_inode(struct inode *, const char *, unsigned int,
 			ext4_fsblk_t, int, const char *, ...);
@@ -2963,9 +2993,6 @@ void __ext4_error_file(struct file *, const char *, unsigned int, ext4_fsblk_t,
 		     const char *, ...);
 extern void __ext4_std_error(struct super_block *, const char *,
 			     unsigned int, int);
-extern __printf(5, 6)
-void __ext4_abort(struct super_block *, const char *, unsigned int, int,
-		  const char *, ...);
 extern __printf(4, 5)
 void __ext4_warning(struct super_block *, const char *, unsigned int,
 		    const char *, ...);
@@ -2995,6 +3022,9 @@ void __ext4_grp_locked_error(const char *, unsigned int,
 #define EXT4_ERROR_FILE(file, block, fmt, a...)				\
 	ext4_error_file((file), __func__, __LINE__, (block), (fmt), ## a)
 
+#define ext4_abort(sb, err, fmt, a...)					\
+	__ext4_error((sb), __func__, __LINE__, true, (err), 0, (fmt), ## a)
+
 #ifdef CONFIG_PRINTK
 
 #define ext4_error_inode(inode, func, line, block, fmt, ...)		\
@@ -3005,11 +3035,11 @@ void __ext4_grp_locked_error(const char *, unsigned int,
 #define ext4_error_file(file, func, line, block, fmt, ...)		\
 	__ext4_error_file(file, func, line, block, fmt, ##__VA_ARGS__)
 #define ext4_error(sb, fmt, ...)					\
-	__ext4_error((sb), __func__, __LINE__, 0, 0, (fmt), ##__VA_ARGS__)
+	__ext4_error((sb), __func__, __LINE__, false, 0, 0, (fmt),	\
+		##__VA_ARGS__)
 #define ext4_error_err(sb, err, fmt, ...)				\
-	__ext4_error((sb), __func__, __LINE__, (err), 0, (fmt), ##__VA_ARGS__)
-#define ext4_abort(sb, err, fmt, ...)					\
-	__ext4_abort((sb), __func__, __LINE__, (err), (fmt), ##__VA_ARGS__)
+	__ext4_error((sb), __func__, __LINE__, false, (err), 0, (fmt),	\
+		##__VA_ARGS__)
 #define ext4_warning(sb, fmt, ...)					\
 	__ext4_warning(sb, __func__, __LINE__, fmt, ##__VA_ARGS__)
 #define ext4_warning_inode(inode, fmt, ...)				\
@@ -3042,17 +3072,12 @@ do {									\
 #define ext4_error(sb, fmt, ...)					\
 do {									\
 	no_printk(fmt, ##__VA_ARGS__);					\
-	__ext4_error(sb, "", 0, 0, 0, " ");				\
+	__ext4_error(sb, "", 0, false, 0, 0, " ");			\
 } while (0)
 #define ext4_error_err(sb, err, fmt, ...)				\
 do {									\
 	no_printk(fmt, ##__VA_ARGS__);					\
-	__ext4_error(sb, "", 0, err, 0, " ");				\
-} while (0)
-#define ext4_abort(sb, err, fmt, ...)					\
-do {									\
-	no_printk(fmt, ##__VA_ARGS__);					\
-	__ext4_abort(sb, "", 0, err, " ");				\
+	__ext4_error(sb, "", 0, false, err, 0, " ");			\
 } while (0)
 #define ext4_warning(sb, fmt, ...)					\
 do {									\
@@ -3361,6 +3386,21 @@ static inline void ext4_unlock_group(struct super_block *sb,
 	spin_unlock(ext4_group_lock_ptr(sb, group));
 }
 
+#ifdef CONFIG_QUOTA
+static inline bool ext4_quota_capable(struct super_block *sb)
+{
+	return (test_opt(sb, QUOTA) || ext4_has_feature_quota(sb));
+}
+
+static inline bool ext4_is_quota_journalled(struct super_block *sb)
+{
+	struct ext4_sb_info *sbi = EXT4_SB(sb);
+
+	return (ext4_has_feature_quota(sb) ||
+		sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]);
+}
+#endif
+
 /*
  * Block validity checking
  */
@@ -3609,7 +3649,6 @@ extern void ext4_io_submit(struct ext4_io_submit *io);
 extern int ext4_bio_write_page(struct ext4_io_submit *io,
 			       struct page *page,
 			       int len,
-			       struct writeback_control *wbc,
 			       bool keep_towrite);
 extern struct ext4_io_end_vec *ext4_alloc_io_end_vec(ext4_io_end_t *io_end);
 extern struct ext4_io_end_vec *ext4_last_io_end_vec(ext4_io_end_t *io_end);

fs/ext4/ext4_jbd2.c

@@ -296,8 +296,8 @@ int __ext4_forget(const char *where, unsigned int line, handle_t *handle,
 	if (err) {
 		ext4_journal_abort_handle(where, line, __func__,
 					  bh, handle, err);
-		__ext4_abort(inode->i_sb, where, line, -err,
-			   "error %d when attempting revoke", err);
+		__ext4_error(inode->i_sb, where, line, true, -err, 0,
+			     "error %d when attempting revoke", err);
 	}
 	BUFFER_TRACE(bh, "exit");
 	return err;

fs/ext4/ext4_jbd2.h

@@ -86,17 +86,14 @@
 #ifdef CONFIG_QUOTA
 /* Amount of blocks needed for quota update - we know that the structure was
  * allocated so we need to update only data block */
-#define EXT4_QUOTA_TRANS_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\
-		ext4_has_feature_quota(sb)) ? 1 : 0)
+#define EXT4_QUOTA_TRANS_BLOCKS(sb) ((ext4_quota_capable(sb)) ? 1 : 0)
 /* Amount of blocks needed for quota insert/delete - we do some block writes
  * but inode, sb and group updates are done only once */
-#define EXT4_QUOTA_INIT_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\
-		ext4_has_feature_quota(sb)) ?\
+#define EXT4_QUOTA_INIT_BLOCKS(sb) ((ext4_quota_capable(sb)) ?\
 		(DQUOT_INIT_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\
 		 +3+DQUOT_INIT_REWRITE) : 0)
 
-#define EXT4_QUOTA_DEL_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\
-		ext4_has_feature_quota(sb)) ?\
+#define EXT4_QUOTA_DEL_BLOCKS(sb) ((ext4_quota_capable(sb)) ?\
 		(DQUOT_DEL_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\
 		 +3+DQUOT_DEL_REWRITE) : 0)
 #else

fs/ext4/extents.c

@@ -5815,8 +5815,8 @@ int ext4_ext_replay_update_ex(struct inode *inode, ext4_lblk_t start,
 	int ret;
 
 	path = ext4_find_extent(inode, start, NULL, 0);
-	if (!path)
-		return -EINVAL;
+	if (IS_ERR(path))
+		return PTR_ERR(path);
 	ex = path[path->p_depth].p_ext;
 	if (!ex) {
 		ret = -EFSCORRUPTED;
@@ -5988,7 +5988,6 @@ int ext4_ext_replay_set_iblocks(struct inode *inode)
 			kfree(path);
 			break;
 		}
-		ex = path2[path2->p_depth].p_ext;
 		for (i = 0; i <= max(path->p_depth, path2->p_depth); i++) {
 			cmp1 = cmp2 = 0;
 			if (i <= path->p_depth)