fs: make the i_state flags an enum (9a98f9e8) · Commits · git / linux-net

include/linux/fs.h

+119 −112

Original line number	Diff line number	Diff line
		@@ -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)
		{