[PATCH v3 00/11] lazytime fix and cleanups

[PATCH v3 00/11] lazytime fix and cleanups

[Eric Biggers]

Hello,

Patch 1 fixes a bug in how __writeback_single_inode() handles lazytime
expirations.  I originally reported this last year
(https://lore.kernel.org/r/20200306004555.GB225345@gmail.com) because it
causes the FS_IOC_REMOVE_ENCRYPTION_KEY ioctl to not work properly, as
the bug causes inodes to remain dirty after a sync.

It also turns out that lazytime on XFS is partially broken because it
doesn't actually write timestamps to disk after a sync() or after
dirtytime_expire_interval.  This is fixed by the same fix.

This supersedes previously proposed fixes, including
https://lore.kernel.org/r/20200307020043.60118-1-tytso@mit.edu and
https://lore.kernel.org/r/20200325122825.1086872-3-hch@lst.de from last
year (which had some issues and didn't fix the XFS bug), and v1 of this
patchset which took a different approach
(https://lore.kernel.org/r/20210105005452.92521-1-ebiggers@kernel.org).

Patches 2-11 then clean up various things related to lazytime and
writeback, such as clarifying the semantics of ->dirty_inode() and the
inode dirty flags, and improving comments.

This patchset applies to v5.11-rc2.

Changed v2 => v3:
  - Changed ext4 patch to add a helper function
    inode_is_dirtytime_only() to include/linux/fs.h.
  - Dropped XFS cleanup patch, as it can be sent/applied separately.
  - Added Reviewed-by's.

Changed v1 => v2:
  - Switched to the fix suggested by Jan Kara, and dropped the
    patches which introduced ->lazytime_expired().
  - Fixed bugs in the fat and ext4 patches.
  - Added patch "fs: improve comments for writeback_single_inode()".
  - Reordered the patches a bit.
  - Added Reviewed-by's.

Eric Biggers (11):
  fs: fix lazytime expiration handling in __writeback_single_inode()
  fs: correctly document the inode dirty flags
  fs: only specify I_DIRTY_TIME when needed in generic_update_time()
  fat: only specify I_DIRTY_TIME when needed in fat_update_time()
  fs: don't call ->dirty_inode for lazytime timestamp updates
  fs: pass only I_DIRTY_INODE flags to ->dirty_inode
  fs: clean up __mark_inode_dirty() a bit
  fs: drop redundant check from __writeback_single_inode()
  fs: improve comments for writeback_single_inode()
  gfs2: don't worry about I_DIRTY_TIME in gfs2_fsync()
  ext4: simplify i_state checks in __ext4_update_other_inode_time()

 Documentation/filesystems/vfs.rst |   5 +-
 fs/ext4/inode.c                   |  20 +----
 fs/f2fs/super.c                   |   3 -
 fs/fat/misc.c                     |  23 +++---
 fs/fs-writeback.c                 | 132 +++++++++++++++++-------------
 fs/gfs2/file.c                    |   4 +-
 fs/gfs2/super.c                   |   2 -
 fs/inode.c                        |  38 +++++----
 include/linux/fs.h                |  33 ++++++--
 9 files changed, 146 insertions(+), 114 deletions(-)


base-commit: e71ba9452f0b5b2e8dc8aa5445198cd9214a6a62
-- 
2.30.0

[f2fs-dev] [PATCH v3 00/11] lazytime fix and cleanups

[Eric Biggers]

Hello,

Patch 1 fixes a bug in how __writeback_single_inode() handles lazytime
expirations.  I originally reported this last year
(https://lore.kernel.org/r/20200306004555.GB225345@gmail.com) because it
causes the FS_IOC_REMOVE_ENCRYPTION_KEY ioctl to not work properly, as
the bug causes inodes to remain dirty after a sync.

It also turns out that lazytime on XFS is partially broken because it
doesn't actually write timestamps to disk after a sync() or after
dirtytime_expire_interval.  This is fixed by the same fix.

This supersedes previously proposed fixes, including
https://lore.kernel.org/r/20200307020043.60118-1-tytso@mit.edu and
https://lore.kernel.org/r/20200325122825.1086872-3-hch@lst.de from last
year (which had some issues and didn't fix the XFS bug), and v1 of this
patchset which took a different approach
(https://lore.kernel.org/r/20210105005452.92521-1-ebiggers@kernel.org).

Patches 2-11 then clean up various things related to lazytime and
writeback, such as clarifying the semantics of ->dirty_inode() and the
inode dirty flags, and improving comments.

This patchset applies to v5.11-rc2.

Changed v2 => v3:
  - Changed ext4 patch to add a helper function
    inode_is_dirtytime_only() to include/linux/fs.h.
  - Dropped XFS cleanup patch, as it can be sent/applied separately.
  - Added Reviewed-by's.

Changed v1 => v2:
  - Switched to the fix suggested by Jan Kara, and dropped the
    patches which introduced ->lazytime_expired().
  - Fixed bugs in the fat and ext4 patches.
  - Added patch "fs: improve comments for writeback_single_inode()".
  - Reordered the patches a bit.
  - Added Reviewed-by's.

Eric Biggers (11):
  fs: fix lazytime expiration handling in __writeback_single_inode()
  fs: correctly document the inode dirty flags
  fs: only specify I_DIRTY_TIME when needed in generic_update_time()
  fat: only specify I_DIRTY_TIME when needed in fat_update_time()
  fs: don't call ->dirty_inode for lazytime timestamp updates
  fs: pass only I_DIRTY_INODE flags to ->dirty_inode
  fs: clean up __mark_inode_dirty() a bit
  fs: drop redundant check from __writeback_single_inode()
  fs: improve comments for writeback_single_inode()
  gfs2: don't worry about I_DIRTY_TIME in gfs2_fsync()
  ext4: simplify i_state checks in __ext4_update_other_inode_time()

 Documentation/filesystems/vfs.rst |   5 +-
 fs/ext4/inode.c                   |  20 +----
 fs/f2fs/super.c                   |   3 -
 fs/fat/misc.c                     |  23 +++---
 fs/fs-writeback.c                 | 132 +++++++++++++++++-------------
 fs/gfs2/file.c                    |   4 +-
 fs/gfs2/super.c                   |   2 -
 fs/inode.c                        |  38 +++++----
 include/linux/fs.h                |  33 ++++++--
 9 files changed, 146 insertions(+), 114 deletions(-)


base-commit: e71ba9452f0b5b2e8dc8aa5445198cd9214a6a62
-- 
2.30.0



_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

[PATCH v3 01/11] fs: fix lazytime expiration handling in __writeback_single_inode()

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

When lazytime is enabled and an inode is being written due to its
in-memory updated timestamps having expired, either due to a sync() or
syncfs() system call or due to dirtytime_expire_interval having elapsed,
the VFS needs to inform the filesystem so that the filesystem can copy
the inode's timestamps out to the on-disk data structures.

This is done by __writeback_single_inode() calling
mark_inode_dirty_sync(), which then calls ->dirty_inode(I_DIRTY_SYNC).

However, this occurs after __writeback_single_inode() has already
cleared the dirty flags from ->i_state.  This causes two bugs:

- mark_inode_dirty_sync() redirties the inode, causing it to remain
  dirty.  This wastefully causes the inode to be written twice.  But
  more importantly, it breaks cases where sync_filesystem() is expected
  to clean dirty inodes.  This includes the FS_IOC_REMOVE_ENCRYPTION_KEY
  ioctl (as reported at
  https://lore.kernel.org/r/20200306004555.GB225345@gmail.com), as well
  as possibly filesystem freezing (freeze_super()).

- Since ->i_state doesn't contain I_DIRTY_TIME when ->dirty_inode() is
  called from __writeback_single_inode() for lazytime expiration,
  xfs_fs_dirty_inode() ignores the notification.  (XFS only cares about
  lazytime expirations, and it assumes that i_state will contain
  I_DIRTY_TIME during those.)  Therefore, lazy timestamps aren't
  persisted by sync(), syncfs(), or dirtytime_expire_interval on XFS.

Fix this by moving the call to mark_inode_dirty_sync() to earlier in
__writeback_single_inode(), before the dirty flags are cleared from
i_state.  This makes filesystems be properly notified of the timestamp
expiration, and it avoids incorrectly redirtying the inode.

This fixes xfstest generic/580 (which tests
FS_IOC_REMOVE_ENCRYPTION_KEY) when run on ext4 or f2fs with lazytime
enabled.  It also fixes the new lazytime xfstest I've proposed, which
reproduces the above-mentioned XFS bug
(https://lore.kernel.org/r/20210105005818.92978-1-ebiggers@kernel.org).

Alternatively, we could call ->dirty_inode(I_DIRTY_SYNC) directly.  But
due to the introduction of I_SYNC_QUEUED, mark_inode_dirty_sync() is the
right thing to do because mark_inode_dirty_sync() now knows not to move
the inode to a writeback list if it is currently queued for sync.

Fixes: 0ae45f63d4ef ("vfs: add support for a lazytime mount option")
Cc: stable@vger.kernel.org
Depends-on: 5afced3bf281 ("writeback: Avoid skipping inode writeback")
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/fs-writeback.c | 24 +++++++++++++-----------
 1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index acfb55834af23..c41cb887eb7d3 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -1474,21 +1474,25 @@ __writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
 	}
 
 	/*
-	 * Some filesystems may redirty the inode during the writeback
-	 * due to delalloc, clear dirty metadata flags right before
-	 * write_inode()
+	 * If the inode has dirty timestamps and we need to write them, call
+	 * mark_inode_dirty_sync() to notify the filesystem about it and to
+	 * change I_DIRTY_TIME into I_DIRTY_SYNC.
 	 */
-	spin_lock(&inode->i_lock);
-
-	dirty = inode->i_state & I_DIRTY;
 	if ((inode->i_state & I_DIRTY_TIME) &&
-	    ((dirty & I_DIRTY_INODE) ||
-	     wbc->sync_mode == WB_SYNC_ALL || wbc->for_sync ||
+	    (wbc->sync_mode == WB_SYNC_ALL || wbc->for_sync ||
 	     time_after(jiffies, inode->dirtied_time_when +
 			dirtytime_expire_interval * HZ))) {
-		dirty |= I_DIRTY_TIME;
 		trace_writeback_lazytime(inode);
+		mark_inode_dirty_sync(inode);
 	}
+
+	/*
+	 * Some filesystems may redirty the inode during the writeback
+	 * due to delalloc, clear dirty metadata flags right before
+	 * write_inode()
+	 */
+	spin_lock(&inode->i_lock);
+	dirty = inode->i_state & I_DIRTY;
 	inode->i_state &= ~dirty;
 
 	/*
@@ -1509,8 +1513,6 @@ __writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
 
 	spin_unlock(&inode->i_lock);
 
-	if (dirty & I_DIRTY_TIME)
-		mark_inode_dirty_sync(inode);
 	/* Don't write the inode if only I_DIRTY_PAGES was set */
 	if (dirty & ~I_DIRTY_PAGES) {
 		int err = write_inode(inode, wbc);
-- 
2.30.0

[f2fs-dev] [PATCH v3 01/11] fs: fix lazytime expiration handling in __writeback_single_inode()

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

When lazytime is enabled and an inode is being written due to its
in-memory updated timestamps having expired, either due to a sync() or
syncfs() system call or due to dirtytime_expire_interval having elapsed,
the VFS needs to inform the filesystem so that the filesystem can copy
the inode's timestamps out to the on-disk data structures.

This is done by __writeback_single_inode() calling
mark_inode_dirty_sync(), which then calls ->dirty_inode(I_DIRTY_SYNC).

However, this occurs after __writeback_single_inode() has already
cleared the dirty flags from ->i_state.  This causes two bugs:

- mark_inode_dirty_sync() redirties the inode, causing it to remain
  dirty.  This wastefully causes the inode to be written twice.  But
  more importantly, it breaks cases where sync_filesystem() is expected
  to clean dirty inodes.  This includes the FS_IOC_REMOVE_ENCRYPTION_KEY
  ioctl (as reported at
  https://lore.kernel.org/r/20200306004555.GB225345@gmail.com), as well
  as possibly filesystem freezing (freeze_super()).

- Since ->i_state doesn't contain I_DIRTY_TIME when ->dirty_inode() is
  called from __writeback_single_inode() for lazytime expiration,
  xfs_fs_dirty_inode() ignores the notification.  (XFS only cares about
  lazytime expirations, and it assumes that i_state will contain
  I_DIRTY_TIME during those.)  Therefore, lazy timestamps aren't
  persisted by sync(), syncfs(), or dirtytime_expire_interval on XFS.

Fix this by moving the call to mark_inode_dirty_sync() to earlier in
__writeback_single_inode(), before the dirty flags are cleared from
i_state.  This makes filesystems be properly notified of the timestamp
expiration, and it avoids incorrectly redirtying the inode.

This fixes xfstest generic/580 (which tests
FS_IOC_REMOVE_ENCRYPTION_KEY) when run on ext4 or f2fs with lazytime
enabled.  It also fixes the new lazytime xfstest I've proposed, which
reproduces the above-mentioned XFS bug
(https://lore.kernel.org/r/20210105005818.92978-1-ebiggers@kernel.org).

Alternatively, we could call ->dirty_inode(I_DIRTY_SYNC) directly.  But
due to the introduction of I_SYNC_QUEUED, mark_inode_dirty_sync() is the
right thing to do because mark_inode_dirty_sync() now knows not to move
the inode to a writeback list if it is currently queued for sync.

Fixes: 0ae45f63d4ef ("vfs: add support for a lazytime mount option")
Cc: stable@vger.kernel.org
Depends-on: 5afced3bf281 ("writeback: Avoid skipping inode writeback")
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/fs-writeback.c | 24 +++++++++++++-----------
 1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index acfb55834af23..c41cb887eb7d3 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -1474,21 +1474,25 @@ __writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
 	}
 
 	/*
-	 * Some filesystems may redirty the inode during the writeback
-	 * due to delalloc, clear dirty metadata flags right before
-	 * write_inode()
+	 * If the inode has dirty timestamps and we need to write them, call
+	 * mark_inode_dirty_sync() to notify the filesystem about it and to
+	 * change I_DIRTY_TIME into I_DIRTY_SYNC.
 	 */
-	spin_lock(&inode->i_lock);
-
-	dirty = inode->i_state & I_DIRTY;
 	if ((inode->i_state & I_DIRTY_TIME) &&
-	    ((dirty & I_DIRTY_INODE) ||
-	     wbc->sync_mode == WB_SYNC_ALL || wbc->for_sync ||
+	    (wbc->sync_mode == WB_SYNC_ALL || wbc->for_sync ||
 	     time_after(jiffies, inode->dirtied_time_when +
 			dirtytime_expire_interval * HZ))) {
-		dirty |= I_DIRTY_TIME;
 		trace_writeback_lazytime(inode);
+		mark_inode_dirty_sync(inode);
 	}
+
+	/*
+	 * Some filesystems may redirty the inode during the writeback
+	 * due to delalloc, clear dirty metadata flags right before
+	 * write_inode()
+	 */
+	spin_lock(&inode->i_lock);
+	dirty = inode->i_state & I_DIRTY;
 	inode->i_state &= ~dirty;
 
 	/*
@@ -1509,8 +1513,6 @@ __writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
 
 	spin_unlock(&inode->i_lock);
 
-	if (dirty & I_DIRTY_TIME)
-		mark_inode_dirty_sync(inode);
 	/* Don't write the inode if only I_DIRTY_PAGES was set */
 	if (dirty & ~I_DIRTY_PAGES) {
 		int err = write_inode(inode, wbc);
-- 
2.30.0



_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

[PATCH v3 02/11] fs: correctly document the inode dirty flags

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

The documentation for I_DIRTY_SYNC and I_DIRTY_DATASYNC is a bit
misleading, and I_DIRTY_TIME isn't documented at all.  Fix this.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 include/linux/fs.h | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index fd47deea7c176..45a0303b2aeb6 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2084,8 +2084,8 @@ static inline void kiocb_clone(struct kiocb *kiocb, struct kiocb *kiocb_src,
 /*
  * Inode state bits.  Protected by inode->i_lock
  *
- * Three bits determine the dirty state of the inode, I_DIRTY_SYNC,
- * I_DIRTY_DATASYNC and I_DIRTY_PAGES.
+ * Four bits determine the dirty state of the inode: I_DIRTY_SYNC,
+ * I_DIRTY_DATASYNC, I_DIRTY_PAGES, and I_DIRTY_TIME.
  *
  * Four bits define the lifetime of an inode.  Initially, inodes are I_NEW,
  * until that flag is cleared.  I_WILL_FREE, I_FREEING and I_CLEAR are set at
@@ -2094,12 +2094,20 @@ static inline void kiocb_clone(struct kiocb *kiocb, struct kiocb *kiocb_src,
  * Two bits are used for locking and completion notification, I_NEW and I_SYNC.
  *
  * I_DIRTY_SYNC		Inode is dirty, but doesn't have to be written on
- *			fdatasync().  i_atime is the usual cause.
- * I_DIRTY_DATASYNC	Data-related inode changes pending. We keep track of
+ *			fdatasync() (unless I_DIRTY_DATASYNC is also set).
+ *			Timestamp updates are the usual cause.
+ * I_DIRTY_DATASYNC	Data-related inode changes pending.  We keep track of
  *			these changes separately from I_DIRTY_SYNC so that we
  *			don't have to write inode on fdatasync() when only
- *			mtime has changed in it.
+ *			e.g. the timestamps have changed.
  * I_DIRTY_PAGES	Inode has dirty pages.  Inode itself may be clean.
+ * I_DIRTY_TIME		The inode itself only has dirty timestamps, and the
+ *			lazytime mount option is enabled.  We keep track of this
+ *			separately from I_DIRTY_SYNC in order to implement
+ *			lazytime.  This gets cleared if I_DIRTY_INODE
+ *			(I_DIRTY_SYNC and/or I_DIRTY_DATASYNC) gets set.  I.e.
+ *			either I_DIRTY_TIME *or* I_DIRTY_INODE can be set in
+ *			i_state, but not both.  I_DIRTY_PAGES may still be set.
  * I_NEW		Serves as both a mutex and completion notification.
  *			New inodes set I_NEW.  If two processes both create
  *			the same inode, one of them will release its inode and
-- 
2.30.0

[f2fs-dev] [PATCH v3 02/11] fs: correctly document the inode dirty flags

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

The documentation for I_DIRTY_SYNC and I_DIRTY_DATASYNC is a bit
misleading, and I_DIRTY_TIME isn't documented at all.  Fix this.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 include/linux/fs.h | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index fd47deea7c176..45a0303b2aeb6 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2084,8 +2084,8 @@ static inline void kiocb_clone(struct kiocb *kiocb, struct kiocb *kiocb_src,
 /*
  * Inode state bits.  Protected by inode->i_lock
  *
- * Three bits determine the dirty state of the inode, I_DIRTY_SYNC,
- * I_DIRTY_DATASYNC and I_DIRTY_PAGES.
+ * Four bits determine the dirty state of the inode: I_DIRTY_SYNC,
+ * I_DIRTY_DATASYNC, I_DIRTY_PAGES, and I_DIRTY_TIME.
  *
  * Four bits define the lifetime of an inode.  Initially, inodes are I_NEW,
  * until that flag is cleared.  I_WILL_FREE, I_FREEING and I_CLEAR are set at
@@ -2094,12 +2094,20 @@ static inline void kiocb_clone(struct kiocb *kiocb, struct kiocb *kiocb_src,
  * Two bits are used for locking and completion notification, I_NEW and I_SYNC.
  *
  * I_DIRTY_SYNC		Inode is dirty, but doesn't have to be written on
- *			fdatasync().  i_atime is the usual cause.
- * I_DIRTY_DATASYNC	Data-related inode changes pending. We keep track of
+ *			fdatasync() (unless I_DIRTY_DATASYNC is also set).
+ *			Timestamp updates are the usual cause.
+ * I_DIRTY_DATASYNC	Data-related inode changes pending.  We keep track of
  *			these changes separately from I_DIRTY_SYNC so that we
  *			don't have to write inode on fdatasync() when only
- *			mtime has changed in it.
+ *			e.g. the timestamps have changed.
  * I_DIRTY_PAGES	Inode has dirty pages.  Inode itself may be clean.
+ * I_DIRTY_TIME		The inode itself only has dirty timestamps, and the
+ *			lazytime mount option is enabled.  We keep track of this
+ *			separately from I_DIRTY_SYNC in order to implement
+ *			lazytime.  This gets cleared if I_DIRTY_INODE
+ *			(I_DIRTY_SYNC and/or I_DIRTY_DATASYNC) gets set.  I.e.
+ *			either I_DIRTY_TIME *or* I_DIRTY_INODE can be set in
+ *			i_state, but not both.  I_DIRTY_PAGES may still be set.
  * I_NEW		Serves as both a mutex and completion notification.
  *			New inodes set I_NEW.  If two processes both create
  *			the same inode, one of them will release its inode and
-- 
2.30.0



_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

[PATCH v3 03/11] fs: only specify I_DIRTY_TIME when needed in generic_update_time()

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

generic_update_time() always passes I_DIRTY_TIME to
__mark_inode_dirty(), which doesn't really make sense because (a)
generic_update_time() might be asked to do only an i_version update, not
also a timestamps update; and (b) I_DIRTY_TIME is only supposed to be
set in i_state if the filesystem has lazytime enabled, so using it
unconditionally in generic_update_time() is inconsistent.

As a result there is a weird edge case where if only an i_version update
was requested (not also a timestamps update) but it is no longer needed
(i.e. inode_maybe_inc_iversion() returns false), then I_DIRTY_TIME will
be set in i_state even if the filesystem isn't mounted with lazytime.

Fix this by only passing I_DIRTY_TIME to __mark_inode_dirty() if the
timestamps were updated and the filesystem has lazytime enabled.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/inode.c | 38 ++++++++++++++++++++------------------
 1 file changed, 20 insertions(+), 18 deletions(-)

diff --git a/fs/inode.c b/fs/inode.c
index 6442d97d9a4ab..d0fa43d8e9d5c 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1743,24 +1743,26 @@ static int relatime_need_update(struct vfsmount *mnt, struct inode *inode,
 
 int generic_update_time(struct inode *inode, struct timespec64 *time, int flags)
 {
-	int iflags = I_DIRTY_TIME;
-	bool dirty = false;
-
-	if (flags & S_ATIME)
-		inode->i_atime = *time;
-	if (flags & S_VERSION)
-		dirty = inode_maybe_inc_iversion(inode, false);
-	if (flags & S_CTIME)
-		inode->i_ctime = *time;
-	if (flags & S_MTIME)
-		inode->i_mtime = *time;
-	if ((flags & (S_ATIME | S_CTIME | S_MTIME)) &&
-	    !(inode->i_sb->s_flags & SB_LAZYTIME))
-		dirty = true;
-
-	if (dirty)
-		iflags |= I_DIRTY_SYNC;
-	__mark_inode_dirty(inode, iflags);
+	int dirty_flags = 0;
+
+	if (flags & (S_ATIME | S_CTIME | S_MTIME)) {
+		if (flags & S_ATIME)
+			inode->i_atime = *time;
+		if (flags & S_CTIME)
+			inode->i_ctime = *time;
+		if (flags & S_MTIME)
+			inode->i_mtime = *time;
+
+		if (inode->i_sb->s_flags & SB_LAZYTIME)
+			dirty_flags |= I_DIRTY_TIME;
+		else
+			dirty_flags |= I_DIRTY_SYNC;
+	}
+
+	if ((flags & S_VERSION) && inode_maybe_inc_iversion(inode, false))
+		dirty_flags |= I_DIRTY_SYNC;
+
+	__mark_inode_dirty(inode, dirty_flags);
 	return 0;
 }
 EXPORT_SYMBOL(generic_update_time);
-- 
2.30.0

[f2fs-dev] [PATCH v3 03/11] fs: only specify I_DIRTY_TIME when needed in generic_update_time()

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

generic_update_time() always passes I_DIRTY_TIME to
__mark_inode_dirty(), which doesn't really make sense because (a)
generic_update_time() might be asked to do only an i_version update, not
also a timestamps update; and (b) I_DIRTY_TIME is only supposed to be
set in i_state if the filesystem has lazytime enabled, so using it
unconditionally in generic_update_time() is inconsistent.

As a result there is a weird edge case where if only an i_version update
was requested (not also a timestamps update) but it is no longer needed
(i.e. inode_maybe_inc_iversion() returns false), then I_DIRTY_TIME will
be set in i_state even if the filesystem isn't mounted with lazytime.

Fix this by only passing I_DIRTY_TIME to __mark_inode_dirty() if the
timestamps were updated and the filesystem has lazytime enabled.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/inode.c | 38 ++++++++++++++++++++------------------
 1 file changed, 20 insertions(+), 18 deletions(-)

diff --git a/fs/inode.c b/fs/inode.c
index 6442d97d9a4ab..d0fa43d8e9d5c 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1743,24 +1743,26 @@ static int relatime_need_update(struct vfsmount *mnt, struct inode *inode,
 
 int generic_update_time(struct inode *inode, struct timespec64 *time, int flags)
 {
-	int iflags = I_DIRTY_TIME;
-	bool dirty = false;
-
-	if (flags & S_ATIME)
-		inode->i_atime = *time;
-	if (flags & S_VERSION)
-		dirty = inode_maybe_inc_iversion(inode, false);
-	if (flags & S_CTIME)
-		inode->i_ctime = *time;
-	if (flags & S_MTIME)
-		inode->i_mtime = *time;
-	if ((flags & (S_ATIME | S_CTIME | S_MTIME)) &&
-	    !(inode->i_sb->s_flags & SB_LAZYTIME))
-		dirty = true;
-
-	if (dirty)
-		iflags |= I_DIRTY_SYNC;
-	__mark_inode_dirty(inode, iflags);
+	int dirty_flags = 0;
+
+	if (flags & (S_ATIME | S_CTIME | S_MTIME)) {
+		if (flags & S_ATIME)
+			inode->i_atime = *time;
+		if (flags & S_CTIME)
+			inode->i_ctime = *time;
+		if (flags & S_MTIME)
+			inode->i_mtime = *time;
+
+		if (inode->i_sb->s_flags & SB_LAZYTIME)
+			dirty_flags |= I_DIRTY_TIME;
+		else
+			dirty_flags |= I_DIRTY_SYNC;
+	}
+
+	if ((flags & S_VERSION) && inode_maybe_inc_iversion(inode, false))
+		dirty_flags |= I_DIRTY_SYNC;
+
+	__mark_inode_dirty(inode, dirty_flags);
 	return 0;
 }
 EXPORT_SYMBOL(generic_update_time);
-- 
2.30.0



_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

[PATCH v3 04/11] fat: only specify I_DIRTY_TIME when needed in fat_update_time()

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

As was done for generic_update_time(), only pass I_DIRTY_TIME to
__mark_inode_dirty() when the inode's timestamps were actually updated
and lazytime is enabled.  This avoids a weird edge case where
I_DIRTY_TIME could be set in i_state when lazytime isn't enabled.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/fat/misc.c | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/fs/fat/misc.c b/fs/fat/misc.c
index f1b2a1fc2a6a4..18a50a46b57f8 100644
--- a/fs/fat/misc.c
+++ b/fs/fat/misc.c
@@ -329,22 +329,23 @@ EXPORT_SYMBOL_GPL(fat_truncate_time);
 
 int fat_update_time(struct inode *inode, struct timespec64 *now, int flags)
 {
-	int iflags = I_DIRTY_TIME;
-	bool dirty = false;
+	int dirty_flags = 0;
 
 	if (inode->i_ino == MSDOS_ROOT_INO)
 		return 0;
 
-	fat_truncate_time(inode, now, flags);
-	if (flags & S_VERSION)
-		dirty = inode_maybe_inc_iversion(inode, false);
-	if ((flags & (S_ATIME | S_CTIME | S_MTIME)) &&
-	    !(inode->i_sb->s_flags & SB_LAZYTIME))
-		dirty = true;
+	if (flags & (S_ATIME | S_CTIME | S_MTIME)) {
+		fat_truncate_time(inode, now, flags);
+		if (inode->i_sb->s_flags & SB_LAZYTIME)
+			dirty_flags |= I_DIRTY_TIME;
+		else
+			dirty_flags |= I_DIRTY_SYNC;
+	}
+
+	if ((flags & S_VERSION) && inode_maybe_inc_iversion(inode, false))
+		dirty_flags |= I_DIRTY_SYNC;
 
-	if (dirty)
-		iflags |= I_DIRTY_SYNC;
-	__mark_inode_dirty(inode, iflags);
+	__mark_inode_dirty(inode, dirty_flags);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(fat_update_time);
-- 
2.30.0

[f2fs-dev] [PATCH v3 04/11] fat: only specify I_DIRTY_TIME when needed in fat_update_time()

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

As was done for generic_update_time(), only pass I_DIRTY_TIME to
__mark_inode_dirty() when the inode's timestamps were actually updated
and lazytime is enabled.  This avoids a weird edge case where
I_DIRTY_TIME could be set in i_state when lazytime isn't enabled.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/fat/misc.c | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/fs/fat/misc.c b/fs/fat/misc.c
index f1b2a1fc2a6a4..18a50a46b57f8 100644
--- a/fs/fat/misc.c
+++ b/fs/fat/misc.c
@@ -329,22 +329,23 @@ EXPORT_SYMBOL_GPL(fat_truncate_time);
 
 int fat_update_time(struct inode *inode, struct timespec64 *now, int flags)
 {
-	int iflags = I_DIRTY_TIME;
-	bool dirty = false;
+	int dirty_flags = 0;
 
 	if (inode->i_ino == MSDOS_ROOT_INO)
 		return 0;
 
-	fat_truncate_time(inode, now, flags);
-	if (flags & S_VERSION)
-		dirty = inode_maybe_inc_iversion(inode, false);
-	if ((flags & (S_ATIME | S_CTIME | S_MTIME)) &&
-	    !(inode->i_sb->s_flags & SB_LAZYTIME))
-		dirty = true;
+	if (flags & (S_ATIME | S_CTIME | S_MTIME)) {
+		fat_truncate_time(inode, now, flags);
+		if (inode->i_sb->s_flags & SB_LAZYTIME)
+			dirty_flags |= I_DIRTY_TIME;
+		else
+			dirty_flags |= I_DIRTY_SYNC;
+	}
+
+	if ((flags & S_VERSION) && inode_maybe_inc_iversion(inode, false))
+		dirty_flags |= I_DIRTY_SYNC;
 
-	if (dirty)
-		iflags |= I_DIRTY_SYNC;
-	__mark_inode_dirty(inode, iflags);
+	__mark_inode_dirty(inode, dirty_flags);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(fat_update_time);
-- 
2.30.0



_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

[PATCH v3 05/11] fs: don't call ->dirty_inode for lazytime timestamp updates

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

There is no need to call ->dirty_inode for lazytime timestamp updates
(i.e. for __mark_inode_dirty(I_DIRTY_TIME)), since by the definition of
lazytime, filesystems must ignore these updates.  Filesystems only need
to care about the updated timestamps when they expire.

Therefore, only call ->dirty_inode when I_DIRTY_INODE is set.

Based on a patch from Christoph Hellwig:
https://lore.kernel.org/r/20200325122825.1086872-4-hch@lst.de

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/ext4/inode.c   | 12 +-----------
 fs/f2fs/super.c   |  3 ---
 fs/fs-writeback.c |  6 +++---
 fs/gfs2/super.c   |  2 --
 4 files changed, 4 insertions(+), 19 deletions(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 27946882d4ce4..4cc6c7834312f 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -5933,26 +5933,16 @@ int __ext4_mark_inode_dirty(handle_t *handle, struct inode *inode,
  * If the inode is marked synchronous, we don't honour that here - doing
  * so would cause a commit on atime updates, which we don't bother doing.
  * We handle synchronous inodes at the highest possible level.
- *
- * If only the I_DIRTY_TIME flag is set, we can skip everything.  If
- * I_DIRTY_TIME and I_DIRTY_SYNC is set, the only inode fields we need
- * to copy into the on-disk inode structure are the timestamp files.
  */
 void ext4_dirty_inode(struct inode *inode, int flags)
 {
 	handle_t *handle;
 
-	if (flags == I_DIRTY_TIME)
-		return;
 	handle = ext4_journal_start(inode, EXT4_HT_INODE, 2);
 	if (IS_ERR(handle))
-		goto out;
-
+		return;
 	ext4_mark_inode_dirty(handle, inode);
-
 	ext4_journal_stop(handle);
-out:
-	return;
 }
 
 int ext4_change_inode_journal_flag(struct inode *inode, int val)
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index b4a07fe62d1a5..cc98dc49f4a26 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -1196,9 +1196,6 @@ static void f2fs_dirty_inode(struct inode *inode, int flags)
 			inode->i_ino == F2FS_META_INO(sbi))
 		return;
 
-	if (flags == I_DIRTY_TIME)
-		return;
-
 	if (is_inode_flag_set(inode, FI_AUTO_RECOVER))
 		clear_inode_flag(inode, FI_AUTO_RECOVER);
 
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index c41cb887eb7d3..b7616bbd55336 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -2255,16 +2255,16 @@ void __mark_inode_dirty(struct inode *inode, int flags)
 	 * Don't do this for I_DIRTY_PAGES - that doesn't actually
 	 * dirty the inode itself
 	 */
-	if (flags & (I_DIRTY_INODE | I_DIRTY_TIME)) {
+	if (flags & I_DIRTY_INODE) {
 		trace_writeback_dirty_inode_start(inode, flags);
 
 		if (sb->s_op->dirty_inode)
 			sb->s_op->dirty_inode(inode, flags);
 
 		trace_writeback_dirty_inode(inode, flags);
-	}
-	if (flags & I_DIRTY_INODE)
+
 		flags &= ~I_DIRTY_TIME;
+	}
 	dirtytime = flags & I_DIRTY_TIME;
 
 	/*
diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index 2f56acc41c049..042b94288ff11 100644
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -562,8 +562,6 @@ static void gfs2_dirty_inode(struct inode *inode, int flags)
 	int need_endtrans = 0;
 	int ret;
 
-	if (!(flags & I_DIRTY_INODE))
-		return;
 	if (unlikely(gfs2_withdrawn(sdp)))
 		return;
 	if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
-- 
2.30.0

[f2fs-dev] [PATCH v3 05/11] fs: don't call ->dirty_inode for lazytime timestamp updates

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

There is no need to call ->dirty_inode for lazytime timestamp updates
(i.e. for __mark_inode_dirty(I_DIRTY_TIME)), since by the definition of
lazytime, filesystems must ignore these updates.  Filesystems only need
to care about the updated timestamps when they expire.

Therefore, only call ->dirty_inode when I_DIRTY_INODE is set.

Based on a patch from Christoph Hellwig:
https://lore.kernel.org/r/20200325122825.1086872-4-hch@lst.de

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/ext4/inode.c   | 12 +-----------
 fs/f2fs/super.c   |  3 ---
 fs/fs-writeback.c |  6 +++---
 fs/gfs2/super.c   |  2 --
 4 files changed, 4 insertions(+), 19 deletions(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 27946882d4ce4..4cc6c7834312f 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -5933,26 +5933,16 @@ int __ext4_mark_inode_dirty(handle_t *handle, struct inode *inode,
  * If the inode is marked synchronous, we don't honour that here - doing
  * so would cause a commit on atime updates, which we don't bother doing.
  * We handle synchronous inodes at the highest possible level.
- *
- * If only the I_DIRTY_TIME flag is set, we can skip everything.  If
- * I_DIRTY_TIME and I_DIRTY_SYNC is set, the only inode fields we need
- * to copy into the on-disk inode structure are the timestamp files.
  */
 void ext4_dirty_inode(struct inode *inode, int flags)
 {
 	handle_t *handle;
 
-	if (flags == I_DIRTY_TIME)
-		return;
 	handle = ext4_journal_start(inode, EXT4_HT_INODE, 2);
 	if (IS_ERR(handle))
-		goto out;
-
+		return;
 	ext4_mark_inode_dirty(handle, inode);
-
 	ext4_journal_stop(handle);
-out:
-	return;
 }
 
 int ext4_change_inode_journal_flag(struct inode *inode, int val)
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index b4a07fe62d1a5..cc98dc49f4a26 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -1196,9 +1196,6 @@ static void f2fs_dirty_inode(struct inode *inode, int flags)
 			inode->i_ino == F2FS_META_INO(sbi))
 		return;
 
-	if (flags == I_DIRTY_TIME)
-		return;
-
 	if (is_inode_flag_set(inode, FI_AUTO_RECOVER))
 		clear_inode_flag(inode, FI_AUTO_RECOVER);
 
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index c41cb887eb7d3..b7616bbd55336 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -2255,16 +2255,16 @@ void __mark_inode_dirty(struct inode *inode, int flags)
 	 * Don't do this for I_DIRTY_PAGES - that doesn't actually
 	 * dirty the inode itself
 	 */
-	if (flags & (I_DIRTY_INODE | I_DIRTY_TIME)) {
+	if (flags & I_DIRTY_INODE) {
 		trace_writeback_dirty_inode_start(inode, flags);
 
 		if (sb->s_op->dirty_inode)
 			sb->s_op->dirty_inode(inode, flags);
 
 		trace_writeback_dirty_inode(inode, flags);
-	}
-	if (flags & I_DIRTY_INODE)
+
 		flags &= ~I_DIRTY_TIME;
+	}
 	dirtytime = flags & I_DIRTY_TIME;
 
 	/*
diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index 2f56acc41c049..042b94288ff11 100644
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -562,8 +562,6 @@ static void gfs2_dirty_inode(struct inode *inode, int flags)
 	int need_endtrans = 0;
 	int ret;
 
-	if (!(flags & I_DIRTY_INODE))
-		return;
 	if (unlikely(gfs2_withdrawn(sdp)))
 		return;
 	if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
-- 
2.30.0



_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

[PATCH v3 06/11] fs: pass only I_DIRTY_INODE flags to ->dirty_inode

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

->dirty_inode is now only called when I_DIRTY_INODE (I_DIRTY_SYNC and/or
I_DIRTY_DATASYNC) is set.  However it may still be passed other dirty
flags at the same time, provided that these other flags happened to be
passed to __mark_inode_dirty() at the same time as I_DIRTY_INODE.

This doesn't make sense because there is no reason for filesystems to
care about these extra flags.  Nor are filesystems notified about all
updates to these other flags.

Therefore, mask the flags before passing them to ->dirty_inode.

Also properly document ->dirty_inode in vfs.rst.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 Documentation/filesystems/vfs.rst | 5 ++++-
 fs/fs-writeback.c                 | 2 +-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/Documentation/filesystems/vfs.rst b/Documentation/filesystems/vfs.rst
index ca52c82e5bb54..287b80948a40b 100644
--- a/Documentation/filesystems/vfs.rst
+++ b/Documentation/filesystems/vfs.rst
@@ -270,7 +270,10 @@ or bottom half).
 	->alloc_inode.
 
 ``dirty_inode``
-	this method is called by the VFS to mark an inode dirty.
+	this method is called by the VFS when an inode is marked dirty.
+	This is specifically for the inode itself being marked dirty,
+	not its data.  If the update needs to be persisted by fdatasync(),
+	then I_DIRTY_DATASYNC will be set in the flags argument.
 
 ``write_inode``
 	this method is called when the VFS needs to write an inode to
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index b7616bbd55336..2e6064012f7d3 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -2259,7 +2259,7 @@ void __mark_inode_dirty(struct inode *inode, int flags)
 		trace_writeback_dirty_inode_start(inode, flags);
 
 		if (sb->s_op->dirty_inode)
-			sb->s_op->dirty_inode(inode, flags);
+			sb->s_op->dirty_inode(inode, flags & I_DIRTY_INODE);
 
 		trace_writeback_dirty_inode(inode, flags);
 
-- 
2.30.0

[f2fs-dev] [PATCH v3 06/11] fs: pass only I_DIRTY_INODE flags to ->dirty_inode

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

->dirty_inode is now only called when I_DIRTY_INODE (I_DIRTY_SYNC and/or
I_DIRTY_DATASYNC) is set.  However it may still be passed other dirty
flags at the same time, provided that these other flags happened to be
passed to __mark_inode_dirty() at the same time as I_DIRTY_INODE.

This doesn't make sense because there is no reason for filesystems to
care about these extra flags.  Nor are filesystems notified about all
updates to these other flags.

Therefore, mask the flags before passing them to ->dirty_inode.

Also properly document ->dirty_inode in vfs.rst.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 Documentation/filesystems/vfs.rst | 5 ++++-
 fs/fs-writeback.c                 | 2 +-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/Documentation/filesystems/vfs.rst b/Documentation/filesystems/vfs.rst
index ca52c82e5bb54..287b80948a40b 100644
--- a/Documentation/filesystems/vfs.rst
+++ b/Documentation/filesystems/vfs.rst
@@ -270,7 +270,10 @@ or bottom half).
 	->alloc_inode.
 
 ``dirty_inode``
-	this method is called by the VFS to mark an inode dirty.
+	this method is called by the VFS when an inode is marked dirty.
+	This is specifically for the inode itself being marked dirty,
+	not its data.  If the update needs to be persisted by fdatasync(),
+	then I_DIRTY_DATASYNC will be set in the flags argument.
 
 ``write_inode``
 	this method is called when the VFS needs to write an inode to
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index b7616bbd55336..2e6064012f7d3 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -2259,7 +2259,7 @@ void __mark_inode_dirty(struct inode *inode, int flags)
 		trace_writeback_dirty_inode_start(inode, flags);
 
 		if (sb->s_op->dirty_inode)
-			sb->s_op->dirty_inode(inode, flags);
+			sb->s_op->dirty_inode(inode, flags & I_DIRTY_INODE);
 
 		trace_writeback_dirty_inode(inode, flags);
 
-- 
2.30.0



_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

[PATCH v3 07/11] fs: clean up __mark_inode_dirty() a bit

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

Improve some comments, and don't bother checking for the I_DIRTY_TIME
flag in the case where we just cleared it.

Also, warn if I_DIRTY_TIME and I_DIRTY_PAGES are passed to
__mark_inode_dirty() at the same time, as this case isn't handled.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/fs-writeback.c | 49 +++++++++++++++++++++++++++++------------------
 1 file changed, 30 insertions(+), 19 deletions(-)

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 2e6064012f7d3..80ee9816d9df5 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -2219,23 +2219,24 @@ static noinline void block_dump___mark_inode_dirty(struct inode *inode)
 }
 
 /**
- * __mark_inode_dirty -	internal function
+ * __mark_inode_dirty -	internal function to mark an inode dirty
  *
  * @inode: inode to mark
- * @flags: what kind of dirty (i.e. I_DIRTY_SYNC)
+ * @flags: what kind of dirty, e.g. I_DIRTY_SYNC.  This can be a combination of
+ *	   multiple I_DIRTY_* flags, except that I_DIRTY_TIME can't be combined
+ *	   with I_DIRTY_PAGES.
  *
- * Mark an inode as dirty. Callers should use mark_inode_dirty or
- * mark_inode_dirty_sync.
+ * Mark an inode as dirty.  We notify the filesystem, then update the inode's
+ * dirty flags.  Then, if needed we add the inode to the appropriate dirty list.
  *
- * Put the inode on the super block's dirty list.
+ * Most callers should use mark_inode_dirty() or mark_inode_dirty_sync()
+ * instead of calling this directly.
  *
- * CAREFUL! We mark it dirty unconditionally, but move it onto the
- * dirty list only if it is hashed or if it refers to a blockdev.
- * If it was not hashed, it will never be added to the dirty list
- * even if it is later hashed, as it will have been marked dirty already.
+ * CAREFUL!  We only add the inode to the dirty list if it is hashed or if it
+ * refers to a blockdev.  Unhashed inodes will never be added to the dirty list
+ * even if they are later hashed, as they will have been marked dirty already.
  *
- * In short, make sure you hash any inodes _before_ you start marking
- * them dirty.
+ * In short, ensure you hash any inodes _before_ you start marking them dirty.
  *
  * Note that for blockdevs, inode->dirtied_when represents the dirtying time of
  * the block-special inode (/dev/hda1) itself.  And the ->dirtied_when field of
@@ -2247,25 +2248,34 @@ static noinline void block_dump___mark_inode_dirty(struct inode *inode)
 void __mark_inode_dirty(struct inode *inode, int flags)
 {
 	struct super_block *sb = inode->i_sb;
-	int dirtytime;
+	int dirtytime = 0;
 
 	trace_writeback_mark_inode_dirty(inode, flags);
 
-	/*
-	 * Don't do this for I_DIRTY_PAGES - that doesn't actually
-	 * dirty the inode itself
-	 */
 	if (flags & I_DIRTY_INODE) {
+		/*
+		 * Notify the filesystem about the inode being dirtied, so that
+		 * (if needed) it can update on-disk fields and journal the
+		 * inode.  This is only needed when the inode itself is being
+		 * dirtied now.  I.e. it's only needed for I_DIRTY_INODE, not
+		 * for just I_DIRTY_PAGES or I_DIRTY_TIME.
+		 */
 		trace_writeback_dirty_inode_start(inode, flags);
-
 		if (sb->s_op->dirty_inode)
 			sb->s_op->dirty_inode(inode, flags & I_DIRTY_INODE);
-
 		trace_writeback_dirty_inode(inode, flags);
 
+		/* I_DIRTY_INODE supersedes I_DIRTY_TIME. */
 		flags &= ~I_DIRTY_TIME;
+	} else {
+		/*
+		 * Else it's either I_DIRTY_PAGES, I_DIRTY_TIME, or nothing.
+		 * (We don't support setting both I_DIRTY_PAGES and I_DIRTY_TIME
+		 * in one call to __mark_inode_dirty().)
+		 */
+		dirtytime = flags & I_DIRTY_TIME;
+		WARN_ON_ONCE(dirtytime && flags != I_DIRTY_TIME);
 	}
-	dirtytime = flags & I_DIRTY_TIME;
 
 	/*
 	 * Paired with smp_mb() in __writeback_single_inode() for the
@@ -2288,6 +2298,7 @@ void __mark_inode_dirty(struct inode *inode, int flags)
 
 		inode_attach_wb(inode, NULL);
 
+		/* I_DIRTY_INODE supersedes I_DIRTY_TIME. */
 		if (flags & I_DIRTY_INODE)
 			inode->i_state &= ~I_DIRTY_TIME;
 		inode->i_state |= flags;
-- 
2.30.0

[f2fs-dev] [PATCH v3 07/11] fs: clean up __mark_inode_dirty() a bit

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

Improve some comments, and don't bother checking for the I_DIRTY_TIME
flag in the case where we just cleared it.

Also, warn if I_DIRTY_TIME and I_DIRTY_PAGES are passed to
__mark_inode_dirty() at the same time, as this case isn't handled.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/fs-writeback.c | 49 +++++++++++++++++++++++++++++------------------
 1 file changed, 30 insertions(+), 19 deletions(-)

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 2e6064012f7d3..80ee9816d9df5 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -2219,23 +2219,24 @@ static noinline void block_dump___mark_inode_dirty(struct inode *inode)
 }
 
 /**
- * __mark_inode_dirty -	internal function
+ * __mark_inode_dirty -	internal function to mark an inode dirty
  *
  * @inode: inode to mark
- * @flags: what kind of dirty (i.e. I_DIRTY_SYNC)
+ * @flags: what kind of dirty, e.g. I_DIRTY_SYNC.  This can be a combination of
+ *	   multiple I_DIRTY_* flags, except that I_DIRTY_TIME can't be combined
+ *	   with I_DIRTY_PAGES.
  *
- * Mark an inode as dirty. Callers should use mark_inode_dirty or
- * mark_inode_dirty_sync.
+ * Mark an inode as dirty.  We notify the filesystem, then update the inode's
+ * dirty flags.  Then, if needed we add the inode to the appropriate dirty list.
  *
- * Put the inode on the super block's dirty list.
+ * Most callers should use mark_inode_dirty() or mark_inode_dirty_sync()
+ * instead of calling this directly.
  *
- * CAREFUL! We mark it dirty unconditionally, but move it onto the
- * dirty list only if it is hashed or if it refers to a blockdev.
- * If it was not hashed, it will never be added to the dirty list
- * even if it is later hashed, as it will have been marked dirty already.
+ * CAREFUL!  We only add the inode to the dirty list if it is hashed or if it
+ * refers to a blockdev.  Unhashed inodes will never be added to the dirty list
+ * even if they are later hashed, as they will have been marked dirty already.
  *
- * In short, make sure you hash any inodes _before_ you start marking
- * them dirty.
+ * In short, ensure you hash any inodes _before_ you start marking them dirty.
  *
  * Note that for blockdevs, inode->dirtied_when represents the dirtying time of
  * the block-special inode (/dev/hda1) itself.  And the ->dirtied_when field of
@@ -2247,25 +2248,34 @@ static noinline void block_dump___mark_inode_dirty(struct inode *inode)
 void __mark_inode_dirty(struct inode *inode, int flags)
 {
 	struct super_block *sb = inode->i_sb;
-	int dirtytime;
+	int dirtytime = 0;
 
 	trace_writeback_mark_inode_dirty(inode, flags);
 
-	/*
-	 * Don't do this for I_DIRTY_PAGES - that doesn't actually
-	 * dirty the inode itself
-	 */
 	if (flags & I_DIRTY_INODE) {
+		/*
+		 * Notify the filesystem about the inode being dirtied, so that
+		 * (if needed) it can update on-disk fields and journal the
+		 * inode.  This is only needed when the inode itself is being
+		 * dirtied now.  I.e. it's only needed for I_DIRTY_INODE, not
+		 * for just I_DIRTY_PAGES or I_DIRTY_TIME.
+		 */
 		trace_writeback_dirty_inode_start(inode, flags);
-
 		if (sb->s_op->dirty_inode)
 			sb->s_op->dirty_inode(inode, flags & I_DIRTY_INODE);
-
 		trace_writeback_dirty_inode(inode, flags);
 
+		/* I_DIRTY_INODE supersedes I_DIRTY_TIME. */
 		flags &= ~I_DIRTY_TIME;
+	} else {
+		/*
+		 * Else it's either I_DIRTY_PAGES, I_DIRTY_TIME, or nothing.
+		 * (We don't support setting both I_DIRTY_PAGES and I_DIRTY_TIME
+		 * in one call to __mark_inode_dirty().)
+		 */
+		dirtytime = flags & I_DIRTY_TIME;
+		WARN_ON_ONCE(dirtytime && flags != I_DIRTY_TIME);
 	}
-	dirtytime = flags & I_DIRTY_TIME;
 
 	/*
 	 * Paired with smp_mb() in __writeback_single_inode() for the
@@ -2288,6 +2298,7 @@ void __mark_inode_dirty(struct inode *inode, int flags)
 
 		inode_attach_wb(inode, NULL);
 
+		/* I_DIRTY_INODE supersedes I_DIRTY_TIME. */
 		if (flags & I_DIRTY_INODE)
 			inode->i_state &= ~I_DIRTY_TIME;
 		inode->i_state |= flags;
-- 
2.30.0



_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

[PATCH v3 08/11] fs: drop redundant check from __writeback_single_inode()

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

wbc->for_sync implies wbc->sync_mode == WB_SYNC_ALL, so there's no need
to check for both.  Just check for WB_SYNC_ALL.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/fs-writeback.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 80ee9816d9df5..cee1df6e3bd43 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -1479,7 +1479,7 @@ __writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
 	 * change I_DIRTY_TIME into I_DIRTY_SYNC.
 	 */
 	if ((inode->i_state & I_DIRTY_TIME) &&
-	    (wbc->sync_mode == WB_SYNC_ALL || wbc->for_sync ||
+	    (wbc->sync_mode == WB_SYNC_ALL ||
 	     time_after(jiffies, inode->dirtied_time_when +
 			dirtytime_expire_interval * HZ))) {
 		trace_writeback_lazytime(inode);
-- 
2.30.0

[f2fs-dev] [PATCH v3 08/11] fs: drop redundant check from __writeback_single_inode()

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

wbc->for_sync implies wbc->sync_mode == WB_SYNC_ALL, so there's no need
to check for both.  Just check for WB_SYNC_ALL.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/fs-writeback.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 80ee9816d9df5..cee1df6e3bd43 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -1479,7 +1479,7 @@ __writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
 	 * change I_DIRTY_TIME into I_DIRTY_SYNC.
 	 */
 	if ((inode->i_state & I_DIRTY_TIME) &&
-	    (wbc->sync_mode == WB_SYNC_ALL || wbc->for_sync ||
+	    (wbc->sync_mode == WB_SYNC_ALL ||
 	     time_after(jiffies, inode->dirtied_time_when +
 			dirtytime_expire_interval * HZ))) {
 		trace_writeback_lazytime(inode);
-- 
2.30.0



_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

[PATCH v3 09/11] fs: improve comments for writeback_single_inode()

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

Some comments for writeback_single_inode() and
__writeback_single_inode() are outdated or not very helpful, especially
with regards to writeback list handling.  Update them.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/fs-writeback.c | 57 +++++++++++++++++++++++++++--------------------
 1 file changed, 33 insertions(+), 24 deletions(-)

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index cee1df6e3bd43..e91980f493884 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -1442,9 +1442,15 @@ static void requeue_inode(struct inode *inode, struct bdi_writeback *wb,
 }
 
 /*
- * Write out an inode and its dirty pages. Do not update the writeback list
- * linkage. That is left to the caller. The caller is also responsible for
- * setting I_SYNC flag and calling inode_sync_complete() to clear it.
+ * Write out an inode and its dirty pages (or some of its dirty pages, depending
+ * on @wbc->nr_to_write), and clear the relevant dirty flags from i_state.
+ *
+ * This doesn't remove the inode from the writeback list it is on, except
+ * potentially to move it from b_dirty_time to b_dirty due to timestamp
+ * expiration.  The caller is otherwise responsible for writeback list handling.
+ *
+ * The caller is also responsible for setting the I_SYNC flag beforehand and
+ * calling inode_sync_complete() to clear it afterwards.
  */
 static int
 __writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
@@ -1487,9 +1493,10 @@ __writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
 	}
 
 	/*
-	 * Some filesystems may redirty the inode during the writeback
-	 * due to delalloc, clear dirty metadata flags right before
-	 * write_inode()
+	 * Get and clear the dirty flags from i_state.  This needs to be done
+	 * after calling writepages because some filesystems may redirty the
+	 * inode during writepages due to delalloc.  It also needs to be done
+	 * after handling timestamp expiration, as that may dirty the inode too.
 	 */
 	spin_lock(&inode->i_lock);
 	dirty = inode->i_state & I_DIRTY;
@@ -1524,12 +1531,13 @@ __writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
 }
 
 /*
- * Write out an inode's dirty pages. Either the caller has an active reference
- * on the inode or the inode has I_WILL_FREE set.
+ * Write out an inode's dirty data and metadata on-demand, i.e. separately from
+ * the regular batched writeback done by the flusher threads in
+ * writeback_sb_inodes().  @wbc controls various aspects of the write, such as
+ * whether it is a data-integrity sync (%WB_SYNC_ALL) or not (%WB_SYNC_NONE).
  *
- * This function is designed to be called for writing back one inode which
- * we go e.g. from filesystem. Flusher thread uses __writeback_single_inode()
- * and does more profound writeback list handling in writeback_sb_inodes().
+ * To prevent the inode from going away, either the caller must have a reference
+ * to the inode, or the inode must have I_WILL_FREE or I_FREEING set.
  */
 static int writeback_single_inode(struct inode *inode,
 				  struct writeback_control *wbc)
@@ -1544,23 +1552,23 @@ static int writeback_single_inode(struct inode *inode,
 		WARN_ON(inode->i_state & I_WILL_FREE);
 
 	if (inode->i_state & I_SYNC) {
-		if (wbc->sync_mode != WB_SYNC_ALL)
-			goto out;
 		/*
-		 * It's a data-integrity sync. We must wait. Since callers hold
-		 * inode reference or inode has I_WILL_FREE set, it cannot go
-		 * away under us.
+		 * Writeback is already running on the inode.  For WB_SYNC_NONE,
+		 * that's enough and we can just return.  For WB_SYNC_ALL, we
+		 * must wait for the existing writeback to complete, then do
+		 * writeback again if there's anything left.
 		 */
+		if (wbc->sync_mode != WB_SYNC_ALL)
+			goto out;
 		__inode_wait_for_writeback(inode);
 	}
 	WARN_ON(inode->i_state & I_SYNC);
 	/*
-	 * Skip inode if it is clean and we have no outstanding writeback in
-	 * WB_SYNC_ALL mode. We don't want to mess with writeback lists in this
-	 * function since flusher thread may be doing for example sync in
-	 * parallel and if we move the inode, it could get skipped. So here we
-	 * make sure inode is on some writeback list and leave it there unless
-	 * we have completely cleaned the inode.
+	 * If the inode is already fully clean, then there's nothing to do.
+	 *
+	 * For data-integrity syncs we also need to check whether any pages are
+	 * still under writeback, e.g. due to prior WB_SYNC_NONE writeback.  If
+	 * there are any such pages, we'll need to wait for them.
 	 */
 	if (!(inode->i_state & I_DIRTY_ALL) &&
 	    (wbc->sync_mode != WB_SYNC_ALL ||
@@ -1576,8 +1584,9 @@ static int writeback_single_inode(struct inode *inode,
 	wb = inode_to_wb_and_lock_list(inode);
 	spin_lock(&inode->i_lock);
 	/*
-	 * If inode is clean, remove it from writeback lists. Otherwise don't
-	 * touch it. See comment above for explanation.
+	 * If the inode is now fully clean, then it can be safely removed from
+	 * its writeback list (if any).  Otherwise the flusher threads are
+	 * responsible for the writeback lists.
 	 */
 	if (!(inode->i_state & I_DIRTY_ALL))
 		inode_io_list_del_locked(inode, wb);
-- 
2.30.0

[f2fs-dev] [PATCH v3 09/11] fs: improve comments for writeback_single_inode()

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

Some comments for writeback_single_inode() and
__writeback_single_inode() are outdated or not very helpful, especially
with regards to writeback list handling.  Update them.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/fs-writeback.c | 57 +++++++++++++++++++++++++++--------------------
 1 file changed, 33 insertions(+), 24 deletions(-)

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index cee1df6e3bd43..e91980f493884 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -1442,9 +1442,15 @@ static void requeue_inode(struct inode *inode, struct bdi_writeback *wb,
 }
 
 /*
- * Write out an inode and its dirty pages. Do not update the writeback list
- * linkage. That is left to the caller. The caller is also responsible for
- * setting I_SYNC flag and calling inode_sync_complete() to clear it.
+ * Write out an inode and its dirty pages (or some of its dirty pages, depending
+ * on @wbc->nr_to_write), and clear the relevant dirty flags from i_state.
+ *
+ * This doesn't remove the inode from the writeback list it is on, except
+ * potentially to move it from b_dirty_time to b_dirty due to timestamp
+ * expiration.  The caller is otherwise responsible for writeback list handling.
+ *
+ * The caller is also responsible for setting the I_SYNC flag beforehand and
+ * calling inode_sync_complete() to clear it afterwards.
  */
 static int
 __writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
@@ -1487,9 +1493,10 @@ __writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
 	}
 
 	/*
-	 * Some filesystems may redirty the inode during the writeback
-	 * due to delalloc, clear dirty metadata flags right before
-	 * write_inode()
+	 * Get and clear the dirty flags from i_state.  This needs to be done
+	 * after calling writepages because some filesystems may redirty the
+	 * inode during writepages due to delalloc.  It also needs to be done
+	 * after handling timestamp expiration, as that may dirty the inode too.
 	 */
 	spin_lock(&inode->i_lock);
 	dirty = inode->i_state & I_DIRTY;
@@ -1524,12 +1531,13 @@ __writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
 }
 
 /*
- * Write out an inode's dirty pages. Either the caller has an active reference
- * on the inode or the inode has I_WILL_FREE set.
+ * Write out an inode's dirty data and metadata on-demand, i.e. separately from
+ * the regular batched writeback done by the flusher threads in
+ * writeback_sb_inodes().  @wbc controls various aspects of the write, such as
+ * whether it is a data-integrity sync (%WB_SYNC_ALL) or not (%WB_SYNC_NONE).
  *
- * This function is designed to be called for writing back one inode which
- * we go e.g. from filesystem. Flusher thread uses __writeback_single_inode()
- * and does more profound writeback list handling in writeback_sb_inodes().
+ * To prevent the inode from going away, either the caller must have a reference
+ * to the inode, or the inode must have I_WILL_FREE or I_FREEING set.
  */
 static int writeback_single_inode(struct inode *inode,
 				  struct writeback_control *wbc)
@@ -1544,23 +1552,23 @@ static int writeback_single_inode(struct inode *inode,
 		WARN_ON(inode->i_state & I_WILL_FREE);
 
 	if (inode->i_state & I_SYNC) {
-		if (wbc->sync_mode != WB_SYNC_ALL)
-			goto out;
 		/*
-		 * It's a data-integrity sync. We must wait. Since callers hold
-		 * inode reference or inode has I_WILL_FREE set, it cannot go
-		 * away under us.
+		 * Writeback is already running on the inode.  For WB_SYNC_NONE,
+		 * that's enough and we can just return.  For WB_SYNC_ALL, we
+		 * must wait for the existing writeback to complete, then do
+		 * writeback again if there's anything left.
 		 */
+		if (wbc->sync_mode != WB_SYNC_ALL)
+			goto out;
 		__inode_wait_for_writeback(inode);
 	}
 	WARN_ON(inode->i_state & I_SYNC);
 	/*
-	 * Skip inode if it is clean and we have no outstanding writeback in
-	 * WB_SYNC_ALL mode. We don't want to mess with writeback lists in this
-	 * function since flusher thread may be doing for example sync in
-	 * parallel and if we move the inode, it could get skipped. So here we
-	 * make sure inode is on some writeback list and leave it there unless
-	 * we have completely cleaned the inode.
+	 * If the inode is already fully clean, then there's nothing to do.
+	 *
+	 * For data-integrity syncs we also need to check whether any pages are
+	 * still under writeback, e.g. due to prior WB_SYNC_NONE writeback.  If
+	 * there are any such pages, we'll need to wait for them.
 	 */
 	if (!(inode->i_state & I_DIRTY_ALL) &&
 	    (wbc->sync_mode != WB_SYNC_ALL ||
@@ -1576,8 +1584,9 @@ static int writeback_single_inode(struct inode *inode,
 	wb = inode_to_wb_and_lock_list(inode);
 	spin_lock(&inode->i_lock);
 	/*
-	 * If inode is clean, remove it from writeback lists. Otherwise don't
-	 * touch it. See comment above for explanation.
+	 * If the inode is now fully clean, then it can be safely removed from
+	 * its writeback list (if any).  Otherwise the flusher threads are
+	 * responsible for the writeback lists.
 	 */
 	if (!(inode->i_state & I_DIRTY_ALL))
 		inode_io_list_del_locked(inode, wb);
-- 
2.30.0



_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

[PATCH v3 10/11] gfs2: don't worry about I_DIRTY_TIME in gfs2_fsync()

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

The I_DIRTY_TIME flag is primary used within the VFS, and there's no
reason for ->fsync() implementations to do anything with it.  This is
because when !datasync, the VFS will expire dirty timestamps before
calling ->fsync().  (See vfs_fsync_range().)  This turns I_DIRTY_TIME
into I_DIRTY_SYNC.

Therefore, change gfs2_fsync() to not check for I_DIRTY_TIME.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/gfs2/file.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index b39b339feddc9..7fe2497755a37 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -749,7 +749,7 @@ static int gfs2_fsync(struct file *file, loff_t start, loff_t end,
 {
 	struct address_space *mapping = file->f_mapping;
 	struct inode *inode = mapping->host;
-	int sync_state = inode->i_state & I_DIRTY_ALL;
+	int sync_state = inode->i_state & I_DIRTY;
 	struct gfs2_inode *ip = GFS2_I(inode);
 	int ret = 0, ret1 = 0;
 
@@ -762,7 +762,7 @@ static int gfs2_fsync(struct file *file, loff_t start, loff_t end,
 	if (!gfs2_is_jdata(ip))
 		sync_state &= ~I_DIRTY_PAGES;
 	if (datasync)
-		sync_state &= ~(I_DIRTY_SYNC | I_DIRTY_TIME);
+		sync_state &= ~I_DIRTY_SYNC;
 
 	if (sync_state) {
 		ret = sync_inode_metadata(inode, 1);
-- 
2.30.0

[f2fs-dev] [PATCH v3 10/11] gfs2: don't worry about I_DIRTY_TIME in gfs2_fsync()

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

The I_DIRTY_TIME flag is primary used within the VFS, and there's no
reason for ->fsync() implementations to do anything with it.  This is
because when !datasync, the VFS will expire dirty timestamps before
calling ->fsync().  (See vfs_fsync_range().)  This turns I_DIRTY_TIME
into I_DIRTY_SYNC.

Therefore, change gfs2_fsync() to not check for I_DIRTY_TIME.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/gfs2/file.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index b39b339feddc9..7fe2497755a37 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -749,7 +749,7 @@ static int gfs2_fsync(struct file *file, loff_t start, loff_t end,
 {
 	struct address_space *mapping = file->f_mapping;
 	struct inode *inode = mapping->host;
-	int sync_state = inode->i_state & I_DIRTY_ALL;
+	int sync_state = inode->i_state & I_DIRTY;
 	struct gfs2_inode *ip = GFS2_I(inode);
 	int ret = 0, ret1 = 0;
 
@@ -762,7 +762,7 @@ static int gfs2_fsync(struct file *file, loff_t start, loff_t end,
 	if (!gfs2_is_jdata(ip))
 		sync_state &= ~I_DIRTY_PAGES;
 	if (datasync)
-		sync_state &= ~(I_DIRTY_SYNC | I_DIRTY_TIME);
+		sync_state &= ~I_DIRTY_SYNC;
 
 	if (sync_state) {
 		ret = sync_inode_metadata(inode, 1);
-- 
2.30.0



_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

[PATCH v3 11/11] ext4: simplify i_state checks in __ext4_update_other_inode_time()

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

Since I_DIRTY_TIME and I_DIRTY_INODE are mutually exclusive in i_state,
there's no need to check for I_DIRTY_TIME && !I_DIRTY_INODE.  Just check
for I_DIRTY_TIME.

Also introduce a helper function in include/linux/fs.h to do this check.

Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/ext4/inode.c    |  8 ++------
 include/linux/fs.h | 15 +++++++++++++++
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 4cc6c7834312f..d809a06b6ef7f 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -4961,15 +4961,11 @@ static void __ext4_update_other_inode_time(struct super_block *sb,
 	if (!inode)
 		return;
 
-	if ((inode->i_state & (I_FREEING | I_WILL_FREE | I_NEW |
-			       I_DIRTY_INODE)) ||
-	    ((inode->i_state & I_DIRTY_TIME) == 0))
+	if (!inode_is_dirtytime_only(inode))
 		return;
 
 	spin_lock(&inode->i_lock);
-	if (((inode->i_state & (I_FREEING | I_WILL_FREE | I_NEW |
-				I_DIRTY_INODE)) == 0) &&
-	    (inode->i_state & I_DIRTY_TIME)) {
+	if (inode_is_dirtytime_only(inode)) {
 		struct ext4_inode_info	*ei = EXT4_I(inode);
 
 		inode->i_state &= ~I_DIRTY_TIME;
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 45a0303b2aeb6..de0c789104c26 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2194,6 +2194,21 @@ static inline void mark_inode_dirty_sync(struct inode *inode)
 	__mark_inode_dirty(inode, I_DIRTY_SYNC);
 }
 
+/*
+ * Returns true if the given inode itself only has dirty timestamps (its pages
+ * may still be dirty) and isn't currently being allocated or freed.
+ * Filesystems should call this if when writing an inode when lazytime is
+ * enabled, they want to opportunistically write the timestamps of other inodes
+ * located very nearby on-disk, e.g. in the same inode block.  This returns true
+ * if the given inode is in need of such an opportunistic update.  Requires
+ * i_lock, or at least later re-checking under i_lock.
+ */
+static inline bool inode_is_dirtytime_only(struct inode *inode)
+{
+	return (inode->i_state & (I_DIRTY_TIME | I_NEW |
+				  I_FREEING | I_WILL_FREE)) == I_DIRTY_TIME;
+}
+
 extern void inc_nlink(struct inode *inode);
 extern void drop_nlink(struct inode *inode);
 extern void clear_nlink(struct inode *inode);
-- 
2.30.0

[f2fs-dev] [PATCH v3 11/11] ext4: simplify i_state checks in __ext4_update_other_inode_time()

[Eric Biggers]

From: Eric Biggers <ebiggers@google.com>

Since I_DIRTY_TIME and I_DIRTY_INODE are mutually exclusive in i_state,
there's no need to check for I_DIRTY_TIME && !I_DIRTY_INODE.  Just check
for I_DIRTY_TIME.

Also introduce a helper function in include/linux/fs.h to do this check.

Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/ext4/inode.c    |  8 ++------
 include/linux/fs.h | 15 +++++++++++++++
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 4cc6c7834312f..d809a06b6ef7f 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -4961,15 +4961,11 @@ static void __ext4_update_other_inode_time(struct super_block *sb,
 	if (!inode)
 		return;
 
-	if ((inode->i_state & (I_FREEING | I_WILL_FREE | I_NEW |
-			       I_DIRTY_INODE)) ||
-	    ((inode->i_state & I_DIRTY_TIME) == 0))
+	if (!inode_is_dirtytime_only(inode))
 		return;
 
 	spin_lock(&inode->i_lock);
-	if (((inode->i_state & (I_FREEING | I_WILL_FREE | I_NEW |
-				I_DIRTY_INODE)) == 0) &&
-	    (inode->i_state & I_DIRTY_TIME)) {
+	if (inode_is_dirtytime_only(inode)) {
 		struct ext4_inode_info	*ei = EXT4_I(inode);
 
 		inode->i_state &= ~I_DIRTY_TIME;
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 45a0303b2aeb6..de0c789104c26 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2194,6 +2194,21 @@ static inline void mark_inode_dirty_sync(struct inode *inode)
 	__mark_inode_dirty(inode, I_DIRTY_SYNC);
 }
 
+/*
+ * Returns true if the given inode itself only has dirty timestamps (its pages
+ * may still be dirty) and isn't currently being allocated or freed.
+ * Filesystems should call this if when writing an inode when lazytime is
+ * enabled, they want to opportunistically write the timestamps of other inodes
+ * located very nearby on-disk, e.g. in the same inode block.  This returns true
+ * if the given inode is in need of such an opportunistic update.  Requires
+ * i_lock, or at least later re-checking under i_lock.
+ */
+static inline bool inode_is_dirtytime_only(struct inode *inode)
+{
+	return (inode->i_state & (I_DIRTY_TIME | I_NEW |
+				  I_FREEING | I_WILL_FREE)) == I_DIRTY_TIME;
+}
+
 extern void inc_nlink(struct inode *inode);
 extern void drop_nlink(struct inode *inode);
 extern void clear_nlink(struct inode *inode);
-- 
2.30.0



_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

Re: [PATCH v3 11/11] ext4: simplify i_state checks in __ext4_update_other_inode_time()

[Christoph Hellwig]

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>

Re: [f2fs-dev] [PATCH v3 11/11] ext4: simplify i_state checks in __ext4_update_other_inode_time()

[Christoph Hellwig]

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>


_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

Re: [PATCH v3 00/11] lazytime fix and cleanups

[Jan Kara]

Hello!

On Tue 12-01-21 11:02:42, Eric Biggers wrote:
> Patch 1 fixes a bug in how __writeback_single_inode() handles lazytime
> expirations.  I originally reported this last year
> (https://lore.kernel.org/r/20200306004555.GB225345@gmail.com) because it
> causes the FS_IOC_REMOVE_ENCRYPTION_KEY ioctl to not work properly, as
> the bug causes inodes to remain dirty after a sync.
> 
> It also turns out that lazytime on XFS is partially broken because it
> doesn't actually write timestamps to disk after a sync() or after
> dirtytime_expire_interval.  This is fixed by the same fix.
> 
> This supersedes previously proposed fixes, including
> https://lore.kernel.org/r/20200307020043.60118-1-tytso@mit.edu and
> https://lore.kernel.org/r/20200325122825.1086872-3-hch@lst.de from last
> year (which had some issues and didn't fix the XFS bug), and v1 of this
> patchset which took a different approach
> (https://lore.kernel.org/r/20210105005452.92521-1-ebiggers@kernel.org).
> 
> Patches 2-11 then clean up various things related to lazytime and
> writeback, such as clarifying the semantics of ->dirty_inode() and the
> inode dirty flags, and improving comments.
> 
> This patchset applies to v5.11-rc2.

Thanks for the patches. I've picked the patches to my tree. I plan to push
patch 1/11 to Linus later this week, the rest of the cleanups will go to
him during the next merge window.

								Honza

> 
> Changed v2 => v3:
>   - Changed ext4 patch to add a helper function
>     inode_is_dirtytime_only() to include/linux/fs.h.
>   - Dropped XFS cleanup patch, as it can be sent/applied separately.
>   - Added Reviewed-by's.
> 
> Changed v1 => v2:
>   - Switched to the fix suggested by Jan Kara, and dropped the
>     patches which introduced ->lazytime_expired().
>   - Fixed bugs in the fat and ext4 patches.
>   - Added patch "fs: improve comments for writeback_single_inode()".
>   - Reordered the patches a bit.
>   - Added Reviewed-by's.
> 
> Eric Biggers (11):
>   fs: fix lazytime expiration handling in __writeback_single_inode()
>   fs: correctly document the inode dirty flags
>   fs: only specify I_DIRTY_TIME when needed in generic_update_time()
>   fat: only specify I_DIRTY_TIME when needed in fat_update_time()
>   fs: don't call ->dirty_inode for lazytime timestamp updates
>   fs: pass only I_DIRTY_INODE flags to ->dirty_inode
>   fs: clean up __mark_inode_dirty() a bit
>   fs: drop redundant check from __writeback_single_inode()
>   fs: improve comments for writeback_single_inode()
>   gfs2: don't worry about I_DIRTY_TIME in gfs2_fsync()
>   ext4: simplify i_state checks in __ext4_update_other_inode_time()
> 
>  Documentation/filesystems/vfs.rst |   5 +-
>  fs/ext4/inode.c                   |  20 +----
>  fs/f2fs/super.c                   |   3 -
>  fs/fat/misc.c                     |  23 +++---
>  fs/fs-writeback.c                 | 132 +++++++++++++++++-------------
>  fs/gfs2/file.c                    |   4 +-
>  fs/gfs2/super.c                   |   2 -
>  fs/inode.c                        |  38 +++++----
>  include/linux/fs.h                |  33 ++++++--
>  9 files changed, 146 insertions(+), 114 deletions(-)
> 
> 
> base-commit: e71ba9452f0b5b2e8dc8aa5445198cd9214a6a62
> -- 
> 2.30.0
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR

Re: [f2fs-dev] [PATCH v3 00/11] lazytime fix and cleanups

[Jan Kara]

Hello!

On Tue 12-01-21 11:02:42, Eric Biggers wrote:
> Patch 1 fixes a bug in how __writeback_single_inode() handles lazytime
> expirations.  I originally reported this last year
> (https://lore.kernel.org/r/20200306004555.GB225345@gmail.com) because it
> causes the FS_IOC_REMOVE_ENCRYPTION_KEY ioctl to not work properly, as
> the bug causes inodes to remain dirty after a sync.
> 
> It also turns out that lazytime on XFS is partially broken because it
> doesn't actually write timestamps to disk after a sync() or after
> dirtytime_expire_interval.  This is fixed by the same fix.
> 
> This supersedes previously proposed fixes, including
> https://lore.kernel.org/r/20200307020043.60118-1-tytso@mit.edu and
> https://lore.kernel.org/r/20200325122825.1086872-3-hch@lst.de from last
> year (which had some issues and didn't fix the XFS bug), and v1 of this
> patchset which took a different approach
> (https://lore.kernel.org/r/20210105005452.92521-1-ebiggers@kernel.org).
> 
> Patches 2-11 then clean up various things related to lazytime and
> writeback, such as clarifying the semantics of ->dirty_inode() and the
> inode dirty flags, and improving comments.
> 
> This patchset applies to v5.11-rc2.

Thanks for the patches. I've picked the patches to my tree. I plan to push
patch 1/11 to Linus later this week, the rest of the cleanups will go to
him during the next merge window.

								Honza

> 
> Changed v2 => v3:
>   - Changed ext4 patch to add a helper function
>     inode_is_dirtytime_only() to include/linux/fs.h.
>   - Dropped XFS cleanup patch, as it can be sent/applied separately.
>   - Added Reviewed-by's.
> 
> Changed v1 => v2:
>   - Switched to the fix suggested by Jan Kara, and dropped the
>     patches which introduced ->lazytime_expired().
>   - Fixed bugs in the fat and ext4 patches.
>   - Added patch "fs: improve comments for writeback_single_inode()".
>   - Reordered the patches a bit.
>   - Added Reviewed-by's.
> 
> Eric Biggers (11):
>   fs: fix lazytime expiration handling in __writeback_single_inode()
>   fs: correctly document the inode dirty flags
>   fs: only specify I_DIRTY_TIME when needed in generic_update_time()
>   fat: only specify I_DIRTY_TIME when needed in fat_update_time()
>   fs: don't call ->dirty_inode for lazytime timestamp updates
>   fs: pass only I_DIRTY_INODE flags to ->dirty_inode
>   fs: clean up __mark_inode_dirty() a bit
>   fs: drop redundant check from __writeback_single_inode()
>   fs: improve comments for writeback_single_inode()
>   gfs2: don't worry about I_DIRTY_TIME in gfs2_fsync()
>   ext4: simplify i_state checks in __ext4_update_other_inode_time()
> 
>  Documentation/filesystems/vfs.rst |   5 +-
>  fs/ext4/inode.c                   |  20 +----
>  fs/f2fs/super.c                   |   3 -
>  fs/fat/misc.c                     |  23 +++---
>  fs/fs-writeback.c                 | 132 +++++++++++++++++-------------
>  fs/gfs2/file.c                    |   4 +-
>  fs/gfs2/super.c                   |   2 -
>  fs/inode.c                        |  38 +++++----
>  include/linux/fs.h                |  33 ++++++--
>  9 files changed, 146 insertions(+), 114 deletions(-)
> 
> 
> base-commit: e71ba9452f0b5b2e8dc8aa5445198cd9214a6a62
> -- 
> 2.30.0
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR


_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

Re: [PATCH v3 00/11] lazytime fix and cleanups

[Eric Biggers]

On Wed, Jan 13, 2021 at 05:29:58PM +0100, Jan Kara wrote:
> Hello!
> 
> On Tue 12-01-21 11:02:42, Eric Biggers wrote:
> > Patch 1 fixes a bug in how __writeback_single_inode() handles lazytime
> > expirations.  I originally reported this last year
> > (https://lore.kernel.org/r/20200306004555.GB225345@gmail.com) because it
> > causes the FS_IOC_REMOVE_ENCRYPTION_KEY ioctl to not work properly, as
> > the bug causes inodes to remain dirty after a sync.
> > 
> > It also turns out that lazytime on XFS is partially broken because it
> > doesn't actually write timestamps to disk after a sync() or after
> > dirtytime_expire_interval.  This is fixed by the same fix.
> > 
> > This supersedes previously proposed fixes, including
> > https://lore.kernel.org/r/20200307020043.60118-1-tytso@mit.edu and
> > https://lore.kernel.org/r/20200325122825.1086872-3-hch@lst.de from last
> > year (which had some issues and didn't fix the XFS bug), and v1 of this
> > patchset which took a different approach
> > (https://lore.kernel.org/r/20210105005452.92521-1-ebiggers@kernel.org).
> > 
> > Patches 2-11 then clean up various things related to lazytime and
> > writeback, such as clarifying the semantics of ->dirty_inode() and the
> > inode dirty flags, and improving comments.
> > 
> > This patchset applies to v5.11-rc2.
> 
> Thanks for the patches. I've picked the patches to my tree. I plan to push
> patch 1/11 to Linus later this week, the rest of the cleanups will go to
> him during the next merge window.
> 
> 								Honza

Sounds good, thanks!

- Eric

Re: [f2fs-dev] [PATCH v3 00/11] lazytime fix and cleanups

[Eric Biggers]

On Wed, Jan 13, 2021 at 05:29:58PM +0100, Jan Kara wrote:
> Hello!
> 
> On Tue 12-01-21 11:02:42, Eric Biggers wrote:
> > Patch 1 fixes a bug in how __writeback_single_inode() handles lazytime
> > expirations.  I originally reported this last year
> > (https://lore.kernel.org/r/20200306004555.GB225345@gmail.com) because it
> > causes the FS_IOC_REMOVE_ENCRYPTION_KEY ioctl to not work properly, as
> > the bug causes inodes to remain dirty after a sync.
> > 
> > It also turns out that lazytime on XFS is partially broken because it
> > doesn't actually write timestamps to disk after a sync() or after
> > dirtytime_expire_interval.  This is fixed by the same fix.
> > 
> > This supersedes previously proposed fixes, including
> > https://lore.kernel.org/r/20200307020043.60118-1-tytso@mit.edu and
> > https://lore.kernel.org/r/20200325122825.1086872-3-hch@lst.de from last
> > year (which had some issues and didn't fix the XFS bug), and v1 of this
> > patchset which took a different approach
> > (https://lore.kernel.org/r/20210105005452.92521-1-ebiggers@kernel.org).
> > 
> > Patches 2-11 then clean up various things related to lazytime and
> > writeback, such as clarifying the semantics of ->dirty_inode() and the
> > inode dirty flags, and improving comments.
> > 
> > This patchset applies to v5.11-rc2.
> 
> Thanks for the patches. I've picked the patches to my tree. I plan to push
> patch 1/11 to Linus later this week, the rest of the cleanups will go to
> him during the next merge window.
> 
> 								Honza

Sounds good, thanks!

- Eric


_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel