diff options
Diffstat (limited to 'fs/f2fs/f2fs.h')
-rw-r--r-- | fs/f2fs/f2fs.h | 110 |
1 files changed, 89 insertions, 21 deletions
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index eb22fa91c2b2..8178a9152e49 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -123,6 +123,18 @@ typedef u32 nid_t; #define COMPRESS_EXT_NUM 16 +/* + * An implementation of an rwsem that is explicitly unfair to readers. This + * prevents priority inversion when a low-priority reader acquires the read lock + * while sleeping on the write lock but the write lock is needed by + * higher-priority clients. + */ + +struct f2fs_rwsem { + struct rw_semaphore internal_rwsem; + wait_queue_head_t read_waiters; +}; + struct f2fs_mount_info { unsigned int opt; int write_io_size_bits; /* Write IO size bits */ @@ -752,7 +764,7 @@ struct f2fs_inode_info { /* Use below internally in f2fs*/ unsigned long flags[BITS_TO_LONGS(FI_MAX)]; /* use to pass per-file flags */ - struct rw_semaphore i_sem; /* protect fi info */ + struct f2fs_rwsem i_sem; /* protect fi info */ atomic_t dirty_pages; /* # of dirty pages */ f2fs_hash_t chash; /* hash value of given file name */ unsigned int clevel; /* maximum level of given file name */ @@ -777,8 +789,8 @@ struct f2fs_inode_info { struct extent_tree *extent_tree; /* cached extent_tree entry */ /* avoid racing between foreground op and gc */ - struct rw_semaphore i_gc_rwsem[2]; - struct rw_semaphore i_xattr_sem; /* avoid racing between reading and changing EAs */ + struct f2fs_rwsem i_gc_rwsem[2]; + struct f2fs_rwsem i_xattr_sem; /* avoid racing between reading and changing EAs */ int i_extra_isize; /* size of extra space located in i_addr */ kprojid_t i_projid; /* id for project quota */ @@ -904,7 +916,7 @@ struct f2fs_nm_info { /* NAT cache management */ struct radix_tree_root nat_root;/* root of the nat entry cache */ struct radix_tree_root nat_set_root;/* root of the nat set cache */ - struct rw_semaphore nat_tree_lock; /* protect nat entry tree */ + struct f2fs_rwsem nat_tree_lock; /* protect nat entry tree */ struct list_head nat_entries; /* cached nat entry list (clean) */ spinlock_t nat_list_lock; /* protect clean nat entry list */ unsigned int nat_cnt[MAX_NAT_STATE]; /* the # of cached nat entries */ @@ -1017,7 +1029,7 @@ struct f2fs_sm_info { struct dirty_seglist_info *dirty_info; /* dirty segment information */ struct curseg_info *curseg_array; /* active segment information */ - struct rw_semaphore curseg_lock; /* for preventing curseg change */ + struct f2fs_rwsem curseg_lock; /* for preventing curseg change */ block_t seg0_blkaddr; /* block address of 0'th segment */ block_t main_blkaddr; /* start block address of main area */ @@ -1201,11 +1213,11 @@ struct f2fs_bio_info { struct bio *bio; /* bios to merge */ sector_t last_block_in_bio; /* last block number */ struct f2fs_io_info fio; /* store buffered io info. */ - struct rw_semaphore io_rwsem; /* blocking op for bio */ + struct f2fs_rwsem io_rwsem; /* blocking op for bio */ spinlock_t io_lock; /* serialize DATA/NODE IOs */ struct list_head io_list; /* track fios */ struct list_head bio_list; /* bio entry list head */ - struct rw_semaphore bio_list_lock; /* lock to protect bio entry list */ + struct f2fs_rwsem bio_list_lock; /* lock to protect bio entry list */ }; #define FDEV(i) (sbi->devs[i]) @@ -1571,7 +1583,7 @@ struct f2fs_sb_info { struct super_block *sb; /* pointer to VFS super block */ struct proc_dir_entry *s_proc; /* proc entry */ struct f2fs_super_block *raw_super; /* raw super block pointer */ - struct rw_semaphore sb_lock; /* lock for raw super block */ + struct f2fs_rwsem sb_lock; /* lock for raw super block */ int valid_super_block; /* valid super block no */ unsigned long s_flag; /* flags for sbi */ struct mutex writepages; /* mutex for writepages() */ @@ -1591,7 +1603,7 @@ struct f2fs_sb_info { /* for bio operations */ struct f2fs_bio_info *write_io[NR_PAGE_TYPE]; /* for write bios */ /* keep migration IO order for LFS mode */ - struct rw_semaphore io_order_lock; + struct f2fs_rwsem io_order_lock; mempool_t *write_io_dummy; /* Dummy pages */ /* for checkpoint */ @@ -1599,10 +1611,10 @@ struct f2fs_sb_info { int cur_cp_pack; /* remain current cp pack */ spinlock_t cp_lock; /* for flag in ckpt */ struct inode *meta_inode; /* cache meta blocks */ - struct rw_semaphore cp_global_sem; /* checkpoint procedure lock */ - struct rw_semaphore cp_rwsem; /* blocking FS operations */ - struct rw_semaphore node_write; /* locking node writes */ - struct rw_semaphore node_change; /* locking node change */ + struct f2fs_rwsem cp_global_sem; /* checkpoint procedure lock */ + struct f2fs_rwsem cp_rwsem; /* blocking FS operations */ + struct f2fs_rwsem node_write; /* locking node writes */ + struct f2fs_rwsem node_change; /* locking node change */ wait_queue_head_t cp_wait; unsigned long last_time[MAX_TIME]; /* to store time in jiffies */ long interval_time[MAX_TIME]; /* to store thresholds */ @@ -1662,7 +1674,7 @@ struct f2fs_sb_info { block_t unusable_block_count; /* # of blocks saved by last cp */ unsigned int nquota_files; /* # of quota sysfile */ - struct rw_semaphore quota_sem; /* blocking cp for flags */ + struct f2fs_rwsem quota_sem; /* blocking cp for flags */ /* # of pages, see count_type */ atomic_t nr_pages[NR_COUNT_TYPE]; @@ -1678,7 +1690,7 @@ struct f2fs_sb_info { struct f2fs_mount_info mount_opt; /* mount options */ /* for cleaning operations */ - struct rw_semaphore gc_lock; /* + struct f2fs_rwsem gc_lock; /* * semaphore for GC, avoid * race between GC and GC or CP */ @@ -1698,7 +1710,7 @@ struct f2fs_sb_info { /* threshold for gc trials on pinned files */ u64 gc_pin_file_threshold; - struct rw_semaphore pin_sem; + struct f2fs_rwsem pin_sem; /* maximum # of trials to find a victim segment for SSR and GC */ unsigned int max_victim_search; @@ -2092,9 +2104,65 @@ static inline void clear_ckpt_flags(struct f2fs_sb_info *sbi, unsigned int f) spin_unlock_irqrestore(&sbi->cp_lock, flags); } +static inline void init_f2fs_rwsem(struct f2fs_rwsem *sem) +{ + init_rwsem(&sem->internal_rwsem); + init_waitqueue_head(&sem->read_waiters); +} + +static inline int f2fs_rwsem_is_locked(struct f2fs_rwsem *sem) +{ + return rwsem_is_locked(&sem->internal_rwsem); +} + +static inline int f2fs_rwsem_is_contended(struct f2fs_rwsem *sem) +{ + return rwsem_is_contended(&sem->internal_rwsem); +} + +static inline void f2fs_down_read(struct f2fs_rwsem *sem) +{ + wait_event(sem->read_waiters, down_read_trylock(&sem->internal_rwsem)); +} + +static inline int f2fs_down_read_trylock(struct f2fs_rwsem *sem) +{ + return down_read_trylock(&sem->internal_rwsem); +} + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +static inline void f2fs_down_read_nested(struct f2fs_rwsem *sem, int subclass) +{ + down_read_nested(&sem->internal_rwsem, subclass); +} +#else +#define f2fs_down_read_nested(sem, subclass) f2fs_down_read(sem) +#endif + +static inline void f2fs_up_read(struct f2fs_rwsem *sem) +{ + up_read(&sem->internal_rwsem); +} + +static inline void f2fs_down_write(struct f2fs_rwsem *sem) +{ + down_write(&sem->internal_rwsem); +} + +static inline int f2fs_down_write_trylock(struct f2fs_rwsem *sem) +{ + return down_write_trylock(&sem->internal_rwsem); +} + +static inline void f2fs_up_write(struct f2fs_rwsem *sem) +{ + up_write(&sem->internal_rwsem); + wake_up_all(&sem->read_waiters); +} + static inline void f2fs_lock_op(struct f2fs_sb_info *sbi) { - down_read(&sbi->cp_rwsem); + f2fs_down_read(&sbi->cp_rwsem); } static inline int f2fs_trylock_op(struct f2fs_sb_info *sbi) @@ -2103,22 +2171,22 @@ static inline int f2fs_trylock_op(struct f2fs_sb_info *sbi) f2fs_show_injection_info(sbi, FAULT_LOCK_OP); return 0; } - return down_read_trylock(&sbi->cp_rwsem); + return f2fs_down_read_trylock(&sbi->cp_rwsem); } static inline void f2fs_unlock_op(struct f2fs_sb_info *sbi) { - up_read(&sbi->cp_rwsem); + f2fs_up_read(&sbi->cp_rwsem); } static inline void f2fs_lock_all(struct f2fs_sb_info *sbi) { - down_write(&sbi->cp_rwsem); + f2fs_down_write(&sbi->cp_rwsem); } static inline void f2fs_unlock_all(struct f2fs_sb_info *sbi) { - up_write(&sbi->cp_rwsem); + f2fs_up_write(&sbi->cp_rwsem); } static inline int __get_cp_reason(struct f2fs_sb_info *sbi) |