diff options
Diffstat (limited to 'include/linux/fs.h')
| -rw-r--r-- | include/linux/fs.h | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/include/linux/fs.h b/include/linux/fs.h index 013b9c2b88e6..d1eeea669d2c 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -776,6 +776,9 @@ static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index) index < ra->start + ra->size); } +#define FILE_MNT_WRITE_TAKEN 1 +#define FILE_MNT_WRITE_RELEASED 2 + struct file { /* * fu_list becomes invalid after file_free is called and queued via @@ -810,6 +813,9 @@ struct file { spinlock_t f_ep_lock; #endif /* #ifdef CONFIG_EPOLL */ struct address_space *f_mapping; +#ifdef CONFIG_DEBUG_WRITECOUNT + unsigned long f_mnt_write_state; +#endif }; extern spinlock_t files_lock; #define file_list_lock() spin_lock(&files_lock); @@ -818,6 +824,49 @@ extern spinlock_t files_lock; #define get_file(x) atomic_inc(&(x)->f_count) #define file_count(x) atomic_read(&(x)->f_count) +#ifdef CONFIG_DEBUG_WRITECOUNT +static inline void file_take_write(struct file *f) +{ + WARN_ON(f->f_mnt_write_state != 0); + f->f_mnt_write_state = FILE_MNT_WRITE_TAKEN; +} +static inline void file_release_write(struct file *f) +{ + f->f_mnt_write_state |= FILE_MNT_WRITE_RELEASED; +} +static inline void file_reset_write(struct file *f) +{ + f->f_mnt_write_state = 0; +} +static inline void file_check_state(struct file *f) +{ + /* + * At this point, either both or neither of these bits + * should be set. + */ + WARN_ON(f->f_mnt_write_state == FILE_MNT_WRITE_TAKEN); + WARN_ON(f->f_mnt_write_state == FILE_MNT_WRITE_RELEASED); +} +static inline int file_check_writeable(struct file *f) +{ + if (f->f_mnt_write_state == FILE_MNT_WRITE_TAKEN) + return 0; + printk(KERN_WARNING "writeable file with no " + "mnt_want_write()\n"); + WARN_ON(1); + return -EINVAL; +} +#else /* !CONFIG_DEBUG_WRITECOUNT */ +static inline void file_take_write(struct file *filp) {} +static inline void file_release_write(struct file *filp) {} +static inline void file_reset_write(struct file *filp) {} +static inline void file_check_state(struct file *filp) {} +static inline int file_check_writeable(struct file *filp) +{ + return 0; +} +#endif /* CONFIG_DEBUG_WRITECOUNT */ + #define MAX_NON_LFS ((1UL<<31) - 1) /* Page cache limit. The filesystems should put that into their s_maxbytes |