diff options
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/fs.h | 32 |
1 files changed, 30 insertions, 2 deletions
diff --git a/include/linux/fs.h b/include/linux/fs.h index 83f5a21b5d26..b58c1b43f734 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -342,7 +342,7 @@ struct block_device { struct inode * bd_inode; dev_t bd_dev; /* not a kdev_t - it's a search key */ int bd_openers; - const struct block_device_operations *bd_op; + struct block_device_operations *bd_op; struct request_queue *bd_queue; struct semaphore bd_sem; /* open/close mutex */ struct list_head bd_inodes; @@ -351,6 +351,8 @@ struct block_device { struct block_device * bd_contains; unsigned bd_block_size; unsigned long bd_offset; + struct semaphore bd_part_sem; + unsigned bd_part_count; }; struct inode { @@ -1083,7 +1085,7 @@ extern void bd_release(struct block_device *); extern void blk_run_queues(void); /* fs/devices.c */ -extern const struct block_device_operations *get_blkfops(unsigned int); +extern struct block_device_operations *get_blkfops(unsigned int); extern int register_chrdev(unsigned int, const char *, struct file_operations *); extern int unregister_chrdev(unsigned int, const char *); extern int chrdev_open(struct inode *, struct file *); @@ -1293,5 +1295,31 @@ static inline ino_t parent_ino(struct dentry *dentry) return res; } +/* NOTE NOTE NOTE: this interface _will_ change in a couple of patches */ + +static inline int dev_lock_part(kdev_t dev) +{ + struct block_device *bdev = bdget(kdev_t_to_nr(dev)); + if (!bdev) + return -ENOMEM; + if (!down_trylock(&bdev->bd_part_sem)) { + if (!bdev->bd_part_count) + return 0; + up(&bdev->bd_part_sem); + } + bdput(bdev); + return -EBUSY; +} + +static inline void dev_unlock_part(kdev_t dev) +{ + struct block_device *bdev = bdget(kdev_t_to_nr(dev)); + if (!bdev) + BUG(); + up(&bdev->bd_part_sem); + bdput(bdev); + bdput(bdev); +} + #endif /* __KERNEL__ */ #endif /* _LINUX_FS_H */ |