diff options
Diffstat (limited to 'fs/ext4/ext4.h')
-rw-r--r-- | fs/ext4/ext4.h | 24 |
1 files changed, 20 insertions, 4 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 58dede76f75f..3dbc56eb4849 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -2432,16 +2432,32 @@ do { \ #define EXT4_FREECLUSTERS_WATERMARK 0 #endif +/* Update i_disksize. Requires i_mutex to avoid races with truncate */ static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize) { - /* - * XXX: replace with spinlock if seen contended -bzzz - */ + WARN_ON_ONCE(S_ISREG(inode->i_mode) && + !mutex_is_locked(&inode->i_mutex)); + down_write(&EXT4_I(inode)->i_data_sem); + if (newsize > EXT4_I(inode)->i_disksize) + EXT4_I(inode)->i_disksize = newsize; + up_write(&EXT4_I(inode)->i_data_sem); +} + +/* + * Update i_disksize after writeback has been started. Races with truncate + * are avoided by checking i_size under i_data_sem. + */ +static inline void ext4_wb_update_i_disksize(struct inode *inode, loff_t newsize) +{ + loff_t i_size; + down_write(&EXT4_I(inode)->i_data_sem); + i_size = i_size_read(inode); + if (newsize > i_size) + newsize = i_size; if (newsize > EXT4_I(inode)->i_disksize) EXT4_I(inode)->i_disksize = newsize; up_write(&EXT4_I(inode)->i_data_sem); - return ; } struct ext4_group_info { |