diff options
| -rw-r--r-- | fs/btrfs/btrfs_inode.h | 19 | ||||
| -rw-r--r-- | fs/btrfs/inode.c | 23 |
2 files changed, 40 insertions, 2 deletions
diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h index c935a774a9f..d9b97d4960e 100644 --- a/fs/btrfs/btrfs_inode.h +++ b/fs/btrfs/btrfs_inode.h @@ -41,6 +41,7 @@ #define BTRFS_INODE_NEEDS_FULL_SYNC 7 #define BTRFS_INODE_COPY_EVERYTHING 8 #define BTRFS_INODE_IN_DELALLOC_LIST 9 +#define BTRFS_INODE_READDIO_NEED_LOCK 10 /* in memory btrfs inode */ struct btrfs_inode { @@ -217,4 +218,22 @@ static inline int btrfs_inode_in_log(struct inode *inode, u64 generation) return 0; } +/* + * Disable DIO read nolock optimization, so new dio readers will be forced + * to grab i_mutex. It is used to avoid the endless truncate due to + * nonlocked dio read. + */ +static inline void btrfs_inode_block_unlocked_dio(struct inode *inode) +{ + set_bit(BTRFS_INODE_READDIO_NEED_LOCK, &BTRFS_I(inode)->runtime_flags); + smp_mb(); +} + +static inline void btrfs_inode_resume_unlocked_dio(struct inode *inode) +{ + smp_mb__before_clear_bit(); + clear_bit(BTRFS_INODE_READDIO_NEED_LOCK, + &BTRFS_I(inode)->runtime_flags); +} + #endif diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index d11f38d8696..c6ee8f1063f 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -3888,6 +3888,12 @@ static int btrfs_setsize(struct inode *inode, struct iattr *attr) /* we don't support swapfiles, so vmtruncate shouldn't fail */ truncate_setsize(inode, newsize); + + /* Disable nonlocked read DIO to avoid the end less truncate */ + btrfs_inode_block_unlocked_dio(inode); + inode_dio_wait(inode); + btrfs_inode_resume_unlocked_dio(inode); + ret = btrfs_truncate(inode); if (ret && inode->i_nlink) btrfs_orphan_del(NULL, inode); @@ -6670,6 +6676,8 @@ static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb, struct file *file = iocb->ki_filp; struct inode *inode = file->f_mapping->host; size_t count = 0; + int flags = 0; + bool wakeup = false; ssize_t ret; if (check_direct_IO(BTRFS_I(inode)->root, rw, iocb, iov, @@ -6681,13 +6689,22 @@ static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb, ret = btrfs_delalloc_reserve_space(inode, count); if (ret) return ret; + } else { + atomic_inc(&inode->i_dio_count); + smp_mb__after_atomic_inc(); + if (unlikely(test_bit(BTRFS_INODE_READDIO_NEED_LOCK, + &BTRFS_I(inode)->runtime_flags))) { + inode_dio_done(inode); + flags = DIO_LOCKING | DIO_SKIP_HOLES; + } else { + wakeup = true; + } } ret = __blockdev_direct_IO(rw, iocb, inode, BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev, iov, offset, nr_segs, btrfs_get_blocks_direct, NULL, - btrfs_submit_direct, 0); - + btrfs_submit_direct, flags); if (rw & WRITE) { if (ret < 0 && ret != -EIOCBQUEUED) btrfs_delalloc_release_space(inode, count); @@ -6700,6 +6717,8 @@ static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb, } btrfs_delalloc_release_metadata(inode, 0); } + if (wakeup) + inode_dio_done(inode); return ret; } |