diff options
Diffstat (limited to 'fs/ext4/ext4_jbd2.h')
| -rw-r--r-- | fs/ext4/ext4_jbd2.h | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/fs/ext4/ext4_jbd2.h b/fs/ext4/ext4_jbd2.h index 05eca817d704..b79ad5126468 100644 --- a/fs/ext4/ext4_jbd2.h +++ b/fs/ext4/ext4_jbd2.h @@ -304,4 +304,28 @@ static inline int ext4_should_writeback_data(struct inode *inode) return 0; } +/* + * This function controls whether or not we should try to go down the + * dioread_nolock code paths, which makes it safe to avoid taking + * i_mutex for direct I/O reads. This only works for extent-based + * files, and it doesn't work for nobh or if data journaling is + * enabled, since the dioread_nolock code uses b_private to pass + * information back to the I/O completion handler, and this conflicts + * with the jbd's use of b_private. + */ +static inline int ext4_should_dioread_nolock(struct inode *inode) +{ + if (!test_opt(inode->i_sb, DIOREAD_NOLOCK)) + return 0; + if (test_opt(inode->i_sb, NOBH)) + return 0; + if (!S_ISREG(inode->i_mode)) + return 0; + if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) + return 0; + if (ext4_should_journal_data(inode)) + return 0; + return 1; +} + #endif /* _EXT4_JBD2_H */ |