[PATCH] ext4: Create helper function for EXT4_IO_END_UNWRITTEN and i_aiodio_unwritten.
From: Tao Ma <hidden>
Date: 2011-08-16 07:08:26
Subsystem:
ext4 file system, filesystems (vfs and infrastructure), the rest · Maintainers:
"Theodore Ts'o", Alexander Viro, Christian Brauner, Linus Torvalds
From: Tao Ma <redacted> EXT4_IO_END_UNWRITTEN flag set and the increase of i_aiodio_unwritten should be done simultaneously since ext4_end_io_nolock always clear the flag and decrease the counter in the same time. We have found some bugs that the flag is set while leaving i_aiodio_unwritten unchanged. So this patch just tries to creat a helper function to wrap them to avoid any future bug. The idea is inspired by Eric. Cc: Eric Sandeen <redacted> Cc: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Tao Ma <redacted> --- Ted, This patch is based on the patch with subject "ext4: Resolve the hang of direct i/o read in handling EXT4_IO_END_UNWRITTEN.". I meant it for the next merge window, but if you think it is also ok for 3.1, go ahead. fs/ext4/ext4.h | 11 +++++++++++ fs/ext4/extents.c | 10 ++-------- fs/ext4/inode.c | 5 +---- fs/ext4/page-io.c | 6 ++---- 4 files changed, 16 insertions(+), 16 deletions(-)
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index e717dfd..514f670 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h@@ -1247,6 +1247,17 @@ static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino) ino <= le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count)); } +static inline int ext4_set_io_unwritten_flag(struct inode *inode, + struct ext4_io_end *io_end) +{ + if (io_end && !(io_end->flag & EXT4_IO_END_UNWRITTEN)) { + io_end->flag |= EXT4_IO_END_UNWRITTEN; + atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten); + return 1; + } + + return 0; +} /* * Inode dynamic state flags */
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 57cf568..c0f8655 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c@@ -3190,10 +3190,7 @@ ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode, * that this IO needs to conversion to written when IO is * completed */ - if (io && !(io->flag & EXT4_IO_END_UNWRITTEN)) { - io->flag = EXT4_IO_END_UNWRITTEN; - atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten); - } else + if (!ext4_set_io_unwritten_flag(inode, io)) ext4_set_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN); if (ext4_should_dioread_nolock(inode)) map->m_flags |= EXT4_MAP_UNINIT;
@@ -3572,10 +3569,7 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, * that we need to perform conversion when IO is done. */ if ((flags & EXT4_GET_BLOCKS_PRE_IO)) { - if (io && !(io->flag & EXT4_IO_END_UNWRITTEN)) { - io->flag = EXT4_IO_END_UNWRITTEN; - atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten); - } else + if (!ext4_set_io_unwritten_flag(inode, io)) ext4_set_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN); }
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 40c0b10..128493b 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c@@ -2673,10 +2673,7 @@ static void ext4_end_io_buffer_write(struct buffer_head *bh, int uptodate) * but being more careful is always safe for the future change. */ inode = io_end->inode; - if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) { - io_end->flag |= EXT4_IO_END_UNWRITTEN; - atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten); - } + ext4_set_io_unwritten_flag(inode, io_end); /* Add the io_end to per-inode completed io list*/ spin_lock_irqsave(&EXT4_I(inode)->i_completed_io_lock, flags);
diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index 78839af..edd2f7b 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c@@ -334,10 +334,8 @@ submit_and_retry: if ((io_end->num_io_pages >= MAX_IO_PAGES) && (io_end->pages[io_end->num_io_pages-1] != io_page)) goto submit_and_retry; - if (buffer_uninit(bh) && !(io_end->flag & EXT4_IO_END_UNWRITTEN)) { - io_end->flag |= EXT4_IO_END_UNWRITTEN; - atomic_inc(&EXT4_I(inode)->i_aiodio_unwritten); - } + if (buffer_uninit(bh)) + ext4_set_io_unwritten_flag(inode, io_end); io->io_end->size += bh->b_size; io->io_next_block++; ret = bio_add_page(io->io_bio, bh->b_page, bh->b_size, bh_offset(bh));
--
1.7.0.4