fs: make the i_state flags an enum

Adjusting i_state flags always means updating the values manually. Bring
these forward into the 2020's and make a nice clean macro for defining
the i_state values as an enum, providing __ variants for the cases where
we need the bit position instead of the actual value, and leaving the
actual NAME as the 1U << bit value.

Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/0da9348da6ece0dce12fccec07b1dd2b8e4cfdab.1756222464.git.josef@toxicpanda.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
This commit is contained in:
Josef Bacik
2025-08-26 11:39:01 -04:00
committed by Christian Brauner
parent bc986b1d75
commit 9a98f9e84c
+119 -112
View File
@@ -664,6 +664,124 @@ is_uncached_acl(struct posix_acl *acl)
#define IOP_MGTIME 0x0020
#define IOP_CACHED_LINK 0x0040
/*
* Inode state bits. Protected by inode->i_lock
*
* 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
* various stages of removing an inode.
*
* 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() (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
* e.g. the timestamps have changed.
* I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean.
* I_DIRTY_TIME The inode itself 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. But
* I_DIRTY_TIME can still be set if I_DIRTY_SYNC is already
* in place because writeback might already be in progress
* and we don't want to lose the time update
* 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
* wait for I_NEW to be released before returning.
* Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
* also cause waiting on I_NEW, without I_NEW actually
* being set. find_inode() uses this to prevent returning
* nearly-dead inodes.
* I_WILL_FREE Must be set when calling write_inode_now() if i_count
* is zero. I_FREEING must be set when I_WILL_FREE is
* cleared.
* I_FREEING Set when inode is about to be freed but still has dirty
* pages or buffers attached or the inode itself is still
* dirty.
* I_CLEAR Added by clear_inode(). In this state the inode is
* clean and can be destroyed. Inode keeps I_FREEING.
*
* Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
* prohibited for many purposes. iget() must wait for
* the inode to be completely released, then create it
* anew. Other functions will just ignore such inodes,
* if appropriate. I_NEW is used for waiting.
*
* I_SYNC Writeback of inode is running. The bit is set during
* data writeback, and cleared with a wakeup on the bit
* address once it is done. The bit is also used to pin
* the inode in memory for flusher thread.
*
* I_REFERENCED Marks the inode as recently references on the LRU list.
*
* I_WB_SWITCH Cgroup bdi_writeback switching in progress. Used to
* synchronize competing switching instances and to tell
* wb stat updates to grab the i_pages lock. See
* inode_switch_wbs_work_fn() for details.
*
* I_OVL_INUSE Used by overlayfs to get exclusive ownership on upper
* and work dirs among overlayfs mounts.
*
* I_CREATING New object's inode in the middle of setting up.
*
* I_DONTCACHE Evict inode as soon as it is not used anymore.
*
* I_SYNC_QUEUED Inode is queued in b_io or b_more_io writeback lists.
* Used to detect that mark_inode_dirty() should not move
* inode between dirty lists.
*
* I_PINNING_FSCACHE_WB Inode is pinning an fscache object for writeback.
*
* I_LRU_ISOLATING Inode is pinned being isolated from LRU without holding
* i_count.
*
* Q: What is the difference between I_WILL_FREE and I_FREEING?
*
* __I_{SYNC,NEW,LRU_ISOLATING} are used to derive unique addresses to wait
* upon. There's one free address left.
*/
enum inode_state_bits {
__I_NEW = 0U,
__I_SYNC = 1U,
__I_LRU_ISOLATING = 2U
/* reserved wait address bit 3 */
};
enum inode_state_flags_t {
I_NEW = (1U << __I_NEW),
I_SYNC = (1U << __I_SYNC),
I_LRU_ISOLATING = (1U << __I_LRU_ISOLATING),
/* reserved flag bit 3 */
I_DIRTY_SYNC = (1U << 4),
I_DIRTY_DATASYNC = (1U << 5),
I_DIRTY_PAGES = (1U << 6),
I_WILL_FREE = (1U << 7),
I_FREEING = (1U << 8),
I_CLEAR = (1U << 9),
I_REFERENCED = (1U << 10),
I_LINKABLE = (1U << 11),
I_DIRTY_TIME = (1U << 12),
I_WB_SWITCH = (1U << 13),
I_OVL_INUSE = (1U << 14),
I_CREATING = (1U << 15),
I_DONTCACHE = (1U << 16),
I_SYNC_QUEUED = (1U << 17),
I_PINNING_NETFS_WB = (1U << 18)
};
#define I_DIRTY_INODE (I_DIRTY_SYNC | I_DIRTY_DATASYNC)
#define I_DIRTY (I_DIRTY_INODE | I_DIRTY_PAGES)
#define I_DIRTY_ALL (I_DIRTY | I_DIRTY_TIME)
/*
* Keep mostly read-only and often accessed (especially for
* the RCU path lookup and 'stat' data) fields at the beginning
@@ -722,7 +840,7 @@ struct inode {
#endif
/* Misc */
u32 i_state;
enum inode_state_flags_t i_state;
/* 32-bit hole */
struct rw_semaphore i_rwsem;
@@ -2482,117 +2600,6 @@ static inline void kiocb_clone(struct kiocb *kiocb, struct kiocb *kiocb_src,
};
}
/*
* Inode state bits. Protected by inode->i_lock
*
* 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
* various stages of removing an inode.
*
* 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() (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
* e.g. the timestamps have changed.
* I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean.
* I_DIRTY_TIME The inode itself 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. But
* I_DIRTY_TIME can still be set if I_DIRTY_SYNC is already
* in place because writeback might already be in progress
* and we don't want to lose the time update
* 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
* wait for I_NEW to be released before returning.
* Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
* also cause waiting on I_NEW, without I_NEW actually
* being set. find_inode() uses this to prevent returning
* nearly-dead inodes.
* I_WILL_FREE Must be set when calling write_inode_now() if i_count
* is zero. I_FREEING must be set when I_WILL_FREE is
* cleared.
* I_FREEING Set when inode is about to be freed but still has dirty
* pages or buffers attached or the inode itself is still
* dirty.
* I_CLEAR Added by clear_inode(). In this state the inode is
* clean and can be destroyed. Inode keeps I_FREEING.
*
* Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
* prohibited for many purposes. iget() must wait for
* the inode to be completely released, then create it
* anew. Other functions will just ignore such inodes,
* if appropriate. I_NEW is used for waiting.
*
* I_SYNC Writeback of inode is running. The bit is set during
* data writeback, and cleared with a wakeup on the bit
* address once it is done. The bit is also used to pin
* the inode in memory for flusher thread.
*
* I_REFERENCED Marks the inode as recently references on the LRU list.
*
* I_WB_SWITCH Cgroup bdi_writeback switching in progress. Used to
* synchronize competing switching instances and to tell
* wb stat updates to grab the i_pages lock. See
* inode_switch_wbs_work_fn() for details.
*
* I_OVL_INUSE Used by overlayfs to get exclusive ownership on upper
* and work dirs among overlayfs mounts.
*
* I_CREATING New object's inode in the middle of setting up.
*
* I_DONTCACHE Evict inode as soon as it is not used anymore.
*
* I_SYNC_QUEUED Inode is queued in b_io or b_more_io writeback lists.
* Used to detect that mark_inode_dirty() should not move
* inode between dirty lists.
*
* I_PINNING_FSCACHE_WB Inode is pinning an fscache object for writeback.
*
* I_LRU_ISOLATING Inode is pinned being isolated from LRU without holding
* i_count.
*
* Q: What is the difference between I_WILL_FREE and I_FREEING?
*
* __I_{SYNC,NEW,LRU_ISOLATING} are used to derive unique addresses to wait
* upon. There's one free address left.
*/
#define __I_NEW 0
#define I_NEW (1 << __I_NEW)
#define __I_SYNC 1
#define I_SYNC (1 << __I_SYNC)
#define __I_LRU_ISOLATING 2
#define I_LRU_ISOLATING (1 << __I_LRU_ISOLATING)
#define I_DIRTY_SYNC (1 << 3)
#define I_DIRTY_DATASYNC (1 << 4)
#define I_DIRTY_PAGES (1 << 5)
#define I_WILL_FREE (1 << 6)
#define I_FREEING (1 << 7)
#define I_CLEAR (1 << 8)
#define I_REFERENCED (1 << 9)
#define I_LINKABLE (1 << 10)
#define I_DIRTY_TIME (1 << 11)
#define I_WB_SWITCH (1 << 12)
#define I_OVL_INUSE (1 << 13)
#define I_CREATING (1 << 14)
#define I_DONTCACHE (1 << 15)
#define I_SYNC_QUEUED (1 << 16)
#define I_PINNING_NETFS_WB (1 << 17)
#define I_DIRTY_INODE (I_DIRTY_SYNC | I_DIRTY_DATASYNC)
#define I_DIRTY (I_DIRTY_INODE | I_DIRTY_PAGES)
#define I_DIRTY_ALL (I_DIRTY | I_DIRTY_TIME)
extern void __mark_inode_dirty(struct inode *, int);
static inline void mark_inode_dirty(struct inode *inode)
{