diff options
author | Matthew Bobrowski <mbobrowski@mbobrowski.org> | 2019-11-05 12:59:22 +0100 |
---|---|---|
committer | Theodore Ts'o <tytso@mit.edu> | 2019-11-05 17:31:39 +0100 |
commit | 548feebec7e93e58b647dba70b3303dcb569c914 (patch) | |
tree | 4f345cdb41a3835dd3c8047ee480a4c942912ddf /fs/ext4 | |
parent | ext4: reorder map.m_flags checks within ext4_iomap_begin() (diff) | |
download | linux-548feebec7e93e58b647dba70b3303dcb569c914.tar.xz linux-548feebec7e93e58b647dba70b3303dcb569c914.zip |
ext4: update direct I/O read lock pattern for IOCB_NOWAIT
This patch updates the lock pattern in ext4_direct_IO_read() to not
block on inode lock in cases of IOCB_NOWAIT direct I/O reads. The
locking condition implemented here is similar to that of 942491c9e6d6
("xfs: fix AIM7 regression").
Fixes: 16c54688592c ("ext4: Allow parallel DIO reads")
Signed-off-by: Matthew Bobrowski <mbobrowski@mbobrowski.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/c5d5e759f91747359fbd2c6f9a36240cf75ad79f.1572949325.git.mbobrowski@mbobrowski.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Diffstat (limited to 'fs/ext4')
-rw-r--r-- | fs/ext4/inode.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index e4b0722717b3..f33fa86fff67 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3881,7 +3881,13 @@ static ssize_t ext4_direct_IO_read(struct kiocb *iocb, struct iov_iter *iter) * writes & truncates and since we take care of writing back page cache, * we are protected against page writeback as well. */ - inode_lock_shared(inode); + if (iocb->ki_flags & IOCB_NOWAIT) { + if (!inode_trylock_shared(inode)) + return -EAGAIN; + } else { + inode_lock_shared(inode); + } + ret = filemap_write_and_wait_range(mapping, iocb->ki_pos, iocb->ki_pos + count - 1); if (ret) |