[PATCH v3 08/13] ext4: fast-commit commit range tracking

[Harshad Shirwadkar <harshadshirwadkar@gmail.com>]

With this patch, we track logical range of file offsets that need to
be committed using fast commit. This allows us to find file extents
that need to be committed during the commit time.

Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
---
 fs/ext4/ext4_jbd2.c | 34 ++++++++++++++++++++++++++++++++++
 fs/ext4/ext4_jbd2.h |  2 ++
 fs/ext4/inline.c    |  4 +++-
 fs/ext4/inode.c     | 17 ++++++++++++++++-
 4 files changed, 55 insertions(+), 2 deletions(-)

diff --git a/fs/ext4/ext4_jbd2.c b/fs/ext4/ext4_jbd2.c
index e70ad7a8e46e..0bb8de2139a5 100644
--- a/fs/ext4/ext4_jbd2.c
+++ b/fs/ext4/ext4_jbd2.c
@@ -405,6 +405,40 @@ void ext4_fc_del(struct inode *inode)
 	spin_unlock(&EXT4_SB(inode->i_sb)->s_fc_lock);
 }
 
+void ext4_fc_update_commit_range(struct inode *inode, ext4_lblk_t start,
+				 ext4_lblk_t end)
+{
+	struct ext4_inode_info *ei = EXT4_I(inode);
+	tid_t running_txn_tid = get_running_txn_tid(inode->i_sb);
+
+	if (!ext4_should_fast_commit(inode->i_sb))
+		return;
+
+	if (inode->i_ino < EXT4_FIRST_INO(inode->i_sb))
+		ext4_debug("Special inode %ld being modified\n", inode->i_ino);
+
+	if (!EXT4_SB(inode->i_sb)->s_fc_eligible)
+		return;
+
+	write_lock(&ei->i_fc.fc_lock);
+	if (ei->i_fc.fc_tid == running_txn_tid) {
+		ei->i_fc.fc_lblk_start = ei->i_fc.fc_lblk_start < start ?
+					 ei->i_fc.fc_lblk_start : start;
+		ei->i_fc.fc_lblk_end = ei->i_fc.fc_lblk_end > end ?
+				     ei->i_fc.fc_lblk_end : end;
+		write_unlock(&ei->i_fc.fc_lock);
+		return;
+	}
+
+	ext4_reset_inode_fc_info(&ei->i_fc);
+	ei->i_fc.fc_eligible = true;
+	ei->i_fc.fc_lblk_start = start;
+	ei->i_fc.fc_lblk_end = end;
+	ei->i_fc.fc_tid = running_txn_tid;
+	write_unlock(&ei->i_fc.fc_lock);
+
+}
+
 void ext4_fc_mark_new(struct inode *inode)
 {
 	struct ext4_inode_info *ei = EXT4_I(inode);
diff --git a/fs/ext4/ext4_jbd2.h b/fs/ext4/ext4_jbd2.h
index 65f20fbfb002..2cb7e7e1f025 100644
--- a/fs/ext4/ext4_jbd2.h
+++ b/fs/ext4/ext4_jbd2.h
@@ -501,6 +501,8 @@ ext4_fc_mark_ineligible(struct inode *inode)
 	spin_unlock(&sbi->s_fc_lock);
 }
 
+void ext4_fc_update_commit_range(struct inode *inode, ext4_lblk_t start,
+				 ext4_lblk_t end);
 
 void ext4_fc_mark_new(struct inode *inode);
 bool ext4_is_inode_fc_ineligible(struct inode *inode);
diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
index fbd561cba098..66b2c0e3f7e4 100644
--- a/fs/ext4/inline.c
+++ b/fs/ext4/inline.c
@@ -966,8 +966,10 @@ int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
 	 * But it's important to update i_size while still holding page lock:
 	 * page writeout could otherwise come in and zero beyond i_size.
 	 */
-	if (pos+copied > inode->i_size)
+	if (pos+copied > inode->i_size) {
+		ext4_fc_update_commit_range(inode, inode->i_size, pos + copied);
 		i_size_write(inode, pos+copied);
+	}
 	unlock_page(page);
 	put_page(page);
 
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 6d2efbd9aba9..ea039e3e1a4d 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1549,6 +1549,8 @@ static int ext4_journalled_write_end(struct file *file,
 			SetPageUptodate(page);
 	}
 	size_changed = ext4_update_inode_size(inode, pos + copied);
+	ext4_fc_update_commit_range(inode, pos, pos + copied);
+
 	ext4_set_inode_state(inode, EXT4_STATE_JDATA);
 	EXT4_I(inode)->i_datasync_tid = handle->h_transaction->t_tid;
 	unlock_page(page);
@@ -2610,8 +2612,12 @@ static int mpage_map_and_submit_extent(handle_t *handle,
 		i_size = i_size_read(inode);
 		if (disksize > i_size)
 			disksize = i_size;
-		if (disksize > EXT4_I(inode)->i_disksize)
+		if (disksize > EXT4_I(inode)->i_disksize) {
+			ext4_fc_update_commit_range(inode,
+						    EXT4_I(inode)->i_disksize,
+						    disksize);
 			EXT4_I(inode)->i_disksize = disksize;
+		}
 		up_write(&EXT4_I(inode)->i_data_sem);
 		err2 = ext4_mark_inode_dirty(handle, inode);
 		ext4_fc_enqueue_inode(handle, inode);
@@ -3220,6 +3226,8 @@ static int ext4_da_write_end(struct file *file,
 		}
 	}
 
+	ext4_fc_update_commit_range(inode, pos, pos + copied);
+
 	if (write_mode != CONVERT_INLINE_DATA &&
 	    ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA) &&
 	    ext4_has_inline_data(inode))
@@ -3627,6 +3635,7 @@ static int ext4_iomap_end(struct inode *inode, loff_t offset, loff_t length,
 		goto orphan_del;
 	}
 
+	ext4_fc_update_commit_range(inode, offset, offset + written);
 	if (ext4_update_inode_size(inode, offset + written)) {
 		ext4_mark_inode_dirty(handle, inode);
 		ext4_fc_enqueue_inode(handle, inode);
@@ -3751,6 +3760,7 @@ static ssize_t ext4_direct_IO_write(struct kiocb *iocb, struct iov_iter *iter)
 		ext4_update_i_disksize(inode, inode->i_size);
 		ext4_journal_stop(handle);
 	}
+	ext4_fc_update_commit_range(inode, offset, offset + count);
 
 	BUG_ON(iocb->private == NULL);
 
@@ -3869,6 +3879,8 @@ static ssize_t ext4_direct_IO_write(struct kiocb *iocb, struct iov_iter *iter)
 				ext4_mark_inode_dirty(handle, inode);
 				ext4_fc_enqueue_inode(handle, inode);
 			}
+			ext4_fc_update_commit_range(inode, offset,
+						    offset + end);
 		}
 		err = ext4_journal_stop(handle);
 		if (ret == 0)
@@ -5327,6 +5339,9 @@ static int ext4_do_update_inode(handle_t *handle,
 			cpu_to_le16(ei->i_file_acl >> 32);
 	raw_inode->i_file_acl_lo = cpu_to_le32(ei->i_file_acl);
 	if (ei->i_disksize != ext4_isize(inode->i_sb, raw_inode)) {
+		ext4_fc_update_commit_range(inode,
+					    ext4_isize(inode->i_sb, raw_inode),
+					    ei->i_disksize);
 		ext4_isize_set(raw_inode, ei->i_disksize);
 		need_datasync = 1;
 	}
-- 
2.23.0.444.g18eeb5a265-goog