| Message ID | 38c2c1dd6f62f82e485b1a767ddeb49606439d67.1567978633.git.mbobrowski@mbobrowski.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | ext4: port direct IO to iomap infrastructure | expand |
On 9/9/19 4:49 AM, Matthew Bobrowski wrote: > For iomap direct IO write code path changes, we need to accommodate > for the case where the block mapping flags passed to ext4_map_blocks() > will result in m_flags having both EXT4_MAP_MAPPED and > EXT4_MAP_UNWRITTEN bits set. In order for the allocated unwritten > extents to be converted properly in the end_io handler, iomap->type > must be set to IOMAP_UNWRITTEN, so we need to reshuffle the > conditional statement in order to achieve this. > > This change is a no-op for DAX code path as the block mapping flag > passed to ext4_map_blocks() when IS_DAX(inode) never results in > EXT4_MAP_MAPPED and EXT4_MAP_UNWRITTEN being set at once. > > Signed-off-by: Matthew Bobrowski <mbobrowski@mbobrowski.org> Looks good to me. Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com> > --- > fs/ext4/inode.c | 17 ++++++++++++++--- > 1 file changed, 14 insertions(+), 3 deletions(-) > > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > index 761ce6286b05..efb184928e51 100644 > --- a/fs/ext4/inode.c > +++ b/fs/ext4/inode.c > @@ -3581,10 +3581,21 @@ static int ext4_iomap_begin(struct inode *inode, loff_t offset, loff_t length, > iomap->type = delalloc ? IOMAP_DELALLOC : IOMAP_HOLE; > iomap->addr = IOMAP_NULL_ADDR; > } else { > - if (map.m_flags & EXT4_MAP_MAPPED) { > - iomap->type = IOMAP_MAPPED; > - } else if (map.m_flags & EXT4_MAP_UNWRITTEN) { > + /* > + * Flags passed to ext4_map_blocks() for direct IO > + * writes can result in m_flags having both > + * EXT4_MAP_MAPPED and EXT4_MAP_UNWRITTEN bits set. In > + * order for allocated unwritten extents to be > + * converted to written extents in the end_io handler > + * correctly, we need to ensure that the iomap->type > + * is also set appropriately in that case. Thus, we > + * need to check whether EXT4_MAP_UNWRITTEN is set > + * first. > + */ > + if (map.m_flags & EXT4_MAP_UNWRITTEN) { > iomap->type = IOMAP_UNWRITTEN; > + } else if (map.m_flags & EXT4_MAP_MAPPED) { > + iomap->type = IOMAP_MAPPED; > } else { > WARN_ON_ONCE(1); > return -EIO; >
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 761ce6286b05..efb184928e51 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3581,10 +3581,21 @@ static int ext4_iomap_begin(struct inode *inode, loff_t offset, loff_t length, iomap->type = delalloc ? IOMAP_DELALLOC : IOMAP_HOLE; iomap->addr = IOMAP_NULL_ADDR; } else { - if (map.m_flags & EXT4_MAP_MAPPED) { - iomap->type = IOMAP_MAPPED; - } else if (map.m_flags & EXT4_MAP_UNWRITTEN) { + /* + * Flags passed to ext4_map_blocks() for direct IO + * writes can result in m_flags having both + * EXT4_MAP_MAPPED and EXT4_MAP_UNWRITTEN bits set. In + * order for allocated unwritten extents to be + * converted to written extents in the end_io handler + * correctly, we need to ensure that the iomap->type + * is also set appropriately in that case. Thus, we + * need to check whether EXT4_MAP_UNWRITTEN is set + * first. + */ + if (map.m_flags & EXT4_MAP_UNWRITTEN) { iomap->type = IOMAP_UNWRITTEN; + } else if (map.m_flags & EXT4_MAP_MAPPED) { + iomap->type = IOMAP_MAPPED; } else { WARN_ON_ONCE(1); return -EIO;
For iomap direct IO write code path changes, we need to accommodate for the case where the block mapping flags passed to ext4_map_blocks() will result in m_flags having both EXT4_MAP_MAPPED and EXT4_MAP_UNWRITTEN bits set. In order for the allocated unwritten extents to be converted properly in the end_io handler, iomap->type must be set to IOMAP_UNWRITTEN, so we need to reshuffle the conditional statement in order to achieve this. This change is a no-op for DAX code path as the block mapping flag passed to ext4_map_blocks() when IS_DAX(inode) never results in EXT4_MAP_MAPPED and EXT4_MAP_UNWRITTEN being set at once. Signed-off-by: Matthew Bobrowski <mbobrowski@mbobrowski.org> --- fs/ext4/inode.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-)