| Message ID | 280de880787dc7c064c309efb685f95d4ff732a9.1571647179.git.mbobrowski@mbobrowski.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | ext4: port direct I/O to iomap infrastructure | expand |
On Mon 21-10-19 20:18:37, Matthew Bobrowski wrote: > This patch introduces a new direct I/O read path which makes use of > the iomap infrastructure. > > The new function ext4_do_read_iter() is responsible for calling into > the iomap infrastructure via iomap_dio_rw(). If the read operation > performed on the inode is not supported, which is checked via > ext4_dio_supported(), then we simply fallback and complete the I/O > using buffered I/O. > > Existing direct I/O read code path has been removed, as it is no > longer required. > > Signed-off-by: Matthew Bobrowski <mbobrowski@mbobrowski.org> Looks good to me. You can add: Reviewed-by: Jan Kara <jack@suse.cz> BTW, I think I gave you my Reviewed-by tag for this patch also last time and this patch didn't change since then. You can just include the tag in your posting in that case. Honza > --- > fs/ext4/file.c | 46 +++++++++++++++++++++++++++++++++++++++++++++- > fs/ext4/inode.c | 32 +------------------------------- > 2 files changed, 46 insertions(+), 32 deletions(-) > > diff --git a/fs/ext4/file.c b/fs/ext4/file.c > index ab75aee3e687..6ea7e00e0204 100644 > --- a/fs/ext4/file.c > +++ b/fs/ext4/file.c > @@ -34,6 +34,46 @@ > #include "xattr.h" > #include "acl.h" > > +static bool ext4_dio_supported(struct inode *inode) > +{ > + if (IS_ENABLED(CONFIG_FS_ENCRYPTION) && IS_ENCRYPTED(inode)) > + return false; > + if (fsverity_active(inode)) > + return false; > + if (ext4_should_journal_data(inode)) > + return false; > + if (ext4_has_inline_data(inode)) > + return false; > + return true; > +} > + > +static int ext4_dio_read_iter(struct kiocb *iocb, struct iov_iter *to) > +{ > + ssize_t ret; > + struct inode *inode = file_inode(iocb->ki_filp); > + > + inode_lock_shared(inode); > + if (!ext4_dio_supported(inode)) { > + inode_unlock_shared(inode); > + /* > + * Fallback to buffered I/O if the operation being performed on > + * the inode is not supported by direct I/O. The IOCB_DIRECT > + * flag needs to be cleared here in order to ensure that the > + * direct I/O path within generic_file_read_iter() is not > + * taken. > + */ > + iocb->ki_flags &= ~IOCB_DIRECT; > + return generic_file_read_iter(iocb, to); > + } > + > + ret = iomap_dio_rw(iocb, to, &ext4_iomap_ops, NULL, > + is_sync_kiocb(iocb)); > + inode_unlock_shared(inode); > + > + file_accessed(iocb->ki_filp); > + return ret; > +} > + > #ifdef CONFIG_FS_DAX > static ssize_t ext4_dax_read_iter(struct kiocb *iocb, struct iov_iter *to) > { > @@ -64,7 +104,9 @@ static ssize_t ext4_dax_read_iter(struct kiocb *iocb, struct iov_iter *to) > > static ssize_t ext4_file_read_iter(struct kiocb *iocb, struct iov_iter *to) > { > - if (unlikely(ext4_forced_shutdown(EXT4_SB(file_inode(iocb->ki_filp)->i_sb)))) > + struct inode *inode = file_inode(iocb->ki_filp); > + > + if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) > return -EIO; > > if (!iov_iter_count(to)) > @@ -74,6 +116,8 @@ static ssize_t ext4_file_read_iter(struct kiocb *iocb, struct iov_iter *to) > if (IS_DAX(file_inode(iocb->ki_filp))) > return ext4_dax_read_iter(iocb, to); > #endif > + if (iocb->ki_flags & IOCB_DIRECT) > + return ext4_dio_read_iter(iocb, to); > return generic_file_read_iter(iocb, to); > } > > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > index ebeedbf3900f..03a9e2b85e46 100644 > --- a/fs/ext4/inode.c > +++ b/fs/ext4/inode.c > @@ -863,9 +863,6 @@ int ext4_dio_get_block(struct inode *inode, sector_t iblock, > { > /* We don't expect handle for direct IO */ > WARN_ON_ONCE(ext4_journal_current_handle()); > - > - if (!create) > - return _ext4_get_block(inode, iblock, bh, 0); > return ext4_get_block_trans(inode, iblock, bh, EXT4_GET_BLOCKS_CREATE); > } > > @@ -3865,30 +3862,6 @@ static ssize_t ext4_direct_IO_write(struct kiocb *iocb, struct iov_iter *iter) > return ret; > } > > -static ssize_t ext4_direct_IO_read(struct kiocb *iocb, struct iov_iter *iter) > -{ > - struct address_space *mapping = iocb->ki_filp->f_mapping; > - struct inode *inode = mapping->host; > - size_t count = iov_iter_count(iter); > - ssize_t ret; > - > - /* > - * Shared inode_lock is enough for us - it protects against concurrent > - * writes & truncates and since we take care of writing back page cache, > - * we are protected against page writeback as well. > - */ > - inode_lock_shared(inode); > - ret = filemap_write_and_wait_range(mapping, iocb->ki_pos, > - iocb->ki_pos + count - 1); > - if (ret) > - goto out_unlock; > - ret = __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev, > - iter, ext4_dio_get_block, NULL, NULL, 0); > -out_unlock: > - inode_unlock_shared(inode); > - return ret; > -} > - > static ssize_t ext4_direct_IO(struct kiocb *iocb, struct iov_iter *iter) > { > struct file *file = iocb->ki_filp; > @@ -3915,10 +3888,7 @@ static ssize_t ext4_direct_IO(struct kiocb *iocb, struct iov_iter *iter) > return 0; > > trace_ext4_direct_IO_enter(inode, offset, count, iov_iter_rw(iter)); > - if (iov_iter_rw(iter) == READ) > - ret = ext4_direct_IO_read(iocb, iter); > - else > - ret = ext4_direct_IO_write(iocb, iter); > + ret = ext4_direct_IO_write(iocb, iter); > trace_ext4_direct_IO_exit(inode, offset, count, iov_iter_rw(iter), ret); > return ret; > } > -- > 2.20.1 > > --<M>--
On Mon, Oct 21, 2019 at 03:41:31PM +0200, Jan Kara wrote: > On Mon 21-10-19 20:18:37, Matthew Bobrowski wrote: > > This patch introduces a new direct I/O read path which makes use of > > the iomap infrastructure. > > > > The new function ext4_do_read_iter() is responsible for calling into > > the iomap infrastructure via iomap_dio_rw(). If the read operation > > performed on the inode is not supported, which is checked via > > ext4_dio_supported(), then we simply fallback and complete the I/O > > using buffered I/O. > > > > Existing direct I/O read code path has been removed, as it is no > > longer required. > > > > Signed-off-by: Matthew Bobrowski <mbobrowski@mbobrowski.org> > > Looks good to me. You can add: > > Reviewed-by: Jan Kara <jack@suse.cz> > > BTW, I think I gave you my Reviewed-by tag for this patch also last time > and this patch didn't change since then. You can just include the tag in > your posting in that case. The lock pattern was dropped here, so I thought I'd just have you review it again to be sure that you didn't object. But anyway, thank you! --<M>--
On 10/21/19 2:48 PM, Matthew Bobrowski wrote: > This patch introduces a new direct I/O read path which makes use of > the iomap infrastructure. > > The new function ext4_do_read_iter() is responsible for calling into > the iomap infrastructure via iomap_dio_rw(). If the read operation > performed on the inode is not supported, which is checked via > ext4_dio_supported(), then we simply fallback and complete the I/O > using buffered I/O. > > Existing direct I/O read code path has been removed, as it is no > longer required. > > Signed-off-by: Matthew Bobrowski <mbobrowski@mbobrowski.org> Patch looks good to me. You may add: Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com> > --- > fs/ext4/file.c | 46 +++++++++++++++++++++++++++++++++++++++++++++- > fs/ext4/inode.c | 32 +------------------------------- > 2 files changed, 46 insertions(+), 32 deletions(-) > > diff --git a/fs/ext4/file.c b/fs/ext4/file.c > index ab75aee3e687..6ea7e00e0204 100644 > --- a/fs/ext4/file.c > +++ b/fs/ext4/file.c > @@ -34,6 +34,46 @@ > #include "xattr.h" > #include "acl.h" > > +static bool ext4_dio_supported(struct inode *inode) > +{ > + if (IS_ENABLED(CONFIG_FS_ENCRYPTION) && IS_ENCRYPTED(inode)) > + return false; > + if (fsverity_active(inode)) > + return false; > + if (ext4_should_journal_data(inode)) > + return false; > + if (ext4_has_inline_data(inode)) > + return false; > + return true; > +} > + > +static int ext4_dio_read_iter(struct kiocb *iocb, struct iov_iter *to) > +{ > + ssize_t ret; > + struct inode *inode = file_inode(iocb->ki_filp); > + > + inode_lock_shared(inode); > + if (!ext4_dio_supported(inode)) { > + inode_unlock_shared(inode); > + /* > + * Fallback to buffered I/O if the operation being performed on > + * the inode is not supported by direct I/O. The IOCB_DIRECT > + * flag needs to be cleared here in order to ensure that the > + * direct I/O path within generic_file_read_iter() is not > + * taken. > + */ > + iocb->ki_flags &= ~IOCB_DIRECT; > + return generic_file_read_iter(iocb, to); > + } > + > + ret = iomap_dio_rw(iocb, to, &ext4_iomap_ops, NULL, > + is_sync_kiocb(iocb)); > + inode_unlock_shared(inode); > + > + file_accessed(iocb->ki_filp); > + return ret; > +} > + > #ifdef CONFIG_FS_DAX > static ssize_t ext4_dax_read_iter(struct kiocb *iocb, struct iov_iter *to) > { > @@ -64,7 +104,9 @@ static ssize_t ext4_dax_read_iter(struct kiocb *iocb, struct iov_iter *to) > > static ssize_t ext4_file_read_iter(struct kiocb *iocb, struct iov_iter *to) > { > - if (unlikely(ext4_forced_shutdown(EXT4_SB(file_inode(iocb->ki_filp)->i_sb)))) > + struct inode *inode = file_inode(iocb->ki_filp); > + > + if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) > return -EIO; > > if (!iov_iter_count(to)) > @@ -74,6 +116,8 @@ static ssize_t ext4_file_read_iter(struct kiocb *iocb, struct iov_iter *to) > if (IS_DAX(file_inode(iocb->ki_filp))) > return ext4_dax_read_iter(iocb, to); > #endif > + if (iocb->ki_flags & IOCB_DIRECT) > + return ext4_dio_read_iter(iocb, to); > return generic_file_read_iter(iocb, to); > } > > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > index ebeedbf3900f..03a9e2b85e46 100644 > --- a/fs/ext4/inode.c > +++ b/fs/ext4/inode.c > @@ -863,9 +863,6 @@ int ext4_dio_get_block(struct inode *inode, sector_t iblock, > { > /* We don't expect handle for direct IO */ > WARN_ON_ONCE(ext4_journal_current_handle()); > - > - if (!create) > - return _ext4_get_block(inode, iblock, bh, 0); > return ext4_get_block_trans(inode, iblock, bh, EXT4_GET_BLOCKS_CREATE); > } > > @@ -3865,30 +3862,6 @@ static ssize_t ext4_direct_IO_write(struct kiocb *iocb, struct iov_iter *iter) > return ret; > } > > -static ssize_t ext4_direct_IO_read(struct kiocb *iocb, struct iov_iter *iter) > -{ > - struct address_space *mapping = iocb->ki_filp->f_mapping; > - struct inode *inode = mapping->host; > - size_t count = iov_iter_count(iter); > - ssize_t ret; > - > - /* > - * Shared inode_lock is enough for us - it protects against concurrent > - * writes & truncates and since we take care of writing back page cache, > - * we are protected against page writeback as well. > - */ > - inode_lock_shared(inode); > - ret = filemap_write_and_wait_range(mapping, iocb->ki_pos, > - iocb->ki_pos + count - 1); > - if (ret) > - goto out_unlock; > - ret = __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev, > - iter, ext4_dio_get_block, NULL, NULL, 0); > -out_unlock: > - inode_unlock_shared(inode); > - return ret; > -} > - > static ssize_t ext4_direct_IO(struct kiocb *iocb, struct iov_iter *iter) > { > struct file *file = iocb->ki_filp; > @@ -3915,10 +3888,7 @@ static ssize_t ext4_direct_IO(struct kiocb *iocb, struct iov_iter *iter) > return 0; > > trace_ext4_direct_IO_enter(inode, offset, count, iov_iter_rw(iter)); > - if (iov_iter_rw(iter) == READ) > - ret = ext4_direct_IO_read(iocb, iter); > - else > - ret = ext4_direct_IO_write(iocb, iter); > + ret = ext4_direct_IO_write(iocb, iter); > trace_ext4_direct_IO_exit(inode, offset, count, iov_iter_rw(iter), ret); > return ret; > } >
diff --git a/fs/ext4/file.c b/fs/ext4/file.c index ab75aee3e687..6ea7e00e0204 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -34,6 +34,46 @@ #include "xattr.h" #include "acl.h" +static bool ext4_dio_supported(struct inode *inode) +{ + if (IS_ENABLED(CONFIG_FS_ENCRYPTION) && IS_ENCRYPTED(inode)) + return false; + if (fsverity_active(inode)) + return false; + if (ext4_should_journal_data(inode)) + return false; + if (ext4_has_inline_data(inode)) + return false; + return true; +} + +static int ext4_dio_read_iter(struct kiocb *iocb, struct iov_iter *to) +{ + ssize_t ret; + struct inode *inode = file_inode(iocb->ki_filp); + + inode_lock_shared(inode); + if (!ext4_dio_supported(inode)) { + inode_unlock_shared(inode); + /* + * Fallback to buffered I/O if the operation being performed on + * the inode is not supported by direct I/O. The IOCB_DIRECT + * flag needs to be cleared here in order to ensure that the + * direct I/O path within generic_file_read_iter() is not + * taken. + */ + iocb->ki_flags &= ~IOCB_DIRECT; + return generic_file_read_iter(iocb, to); + } + + ret = iomap_dio_rw(iocb, to, &ext4_iomap_ops, NULL, + is_sync_kiocb(iocb)); + inode_unlock_shared(inode); + + file_accessed(iocb->ki_filp); + return ret; +} + #ifdef CONFIG_FS_DAX static ssize_t ext4_dax_read_iter(struct kiocb *iocb, struct iov_iter *to) { @@ -64,7 +104,9 @@ static ssize_t ext4_dax_read_iter(struct kiocb *iocb, struct iov_iter *to) static ssize_t ext4_file_read_iter(struct kiocb *iocb, struct iov_iter *to) { - if (unlikely(ext4_forced_shutdown(EXT4_SB(file_inode(iocb->ki_filp)->i_sb)))) + struct inode *inode = file_inode(iocb->ki_filp); + + if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) return -EIO; if (!iov_iter_count(to)) @@ -74,6 +116,8 @@ static ssize_t ext4_file_read_iter(struct kiocb *iocb, struct iov_iter *to) if (IS_DAX(file_inode(iocb->ki_filp))) return ext4_dax_read_iter(iocb, to); #endif + if (iocb->ki_flags & IOCB_DIRECT) + return ext4_dio_read_iter(iocb, to); return generic_file_read_iter(iocb, to); } diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index ebeedbf3900f..03a9e2b85e46 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -863,9 +863,6 @@ int ext4_dio_get_block(struct inode *inode, sector_t iblock, { /* We don't expect handle for direct IO */ WARN_ON_ONCE(ext4_journal_current_handle()); - - if (!create) - return _ext4_get_block(inode, iblock, bh, 0); return ext4_get_block_trans(inode, iblock, bh, EXT4_GET_BLOCKS_CREATE); } @@ -3865,30 +3862,6 @@ static ssize_t ext4_direct_IO_write(struct kiocb *iocb, struct iov_iter *iter) return ret; } -static ssize_t ext4_direct_IO_read(struct kiocb *iocb, struct iov_iter *iter) -{ - struct address_space *mapping = iocb->ki_filp->f_mapping; - struct inode *inode = mapping->host; - size_t count = iov_iter_count(iter); - ssize_t ret; - - /* - * Shared inode_lock is enough for us - it protects against concurrent - * writes & truncates and since we take care of writing back page cache, - * we are protected against page writeback as well. - */ - inode_lock_shared(inode); - ret = filemap_write_and_wait_range(mapping, iocb->ki_pos, - iocb->ki_pos + count - 1); - if (ret) - goto out_unlock; - ret = __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev, - iter, ext4_dio_get_block, NULL, NULL, 0); -out_unlock: - inode_unlock_shared(inode); - return ret; -} - static ssize_t ext4_direct_IO(struct kiocb *iocb, struct iov_iter *iter) { struct file *file = iocb->ki_filp; @@ -3915,10 +3888,7 @@ static ssize_t ext4_direct_IO(struct kiocb *iocb, struct iov_iter *iter) return 0; trace_ext4_direct_IO_enter(inode, offset, count, iov_iter_rw(iter)); - if (iov_iter_rw(iter) == READ) - ret = ext4_direct_IO_read(iocb, iter); - else - ret = ext4_direct_IO_write(iocb, iter); + ret = ext4_direct_IO_write(iocb, iter); trace_ext4_direct_IO_exit(inode, offset, count, iov_iter_rw(iter), ret); return ret; }
This patch introduces a new direct I/O read path which makes use of the iomap infrastructure. The new function ext4_do_read_iter() is responsible for calling into the iomap infrastructure via iomap_dio_rw(). If the read operation performed on the inode is not supported, which is checked via ext4_dio_supported(), then we simply fallback and complete the I/O using buffered I/O. Existing direct I/O read code path has been removed, as it is no longer required. Signed-off-by: Matthew Bobrowski <mbobrowski@mbobrowski.org> --- fs/ext4/file.c | 46 +++++++++++++++++++++++++++++++++++++++++++++- fs/ext4/inode.c | 32 +------------------------------- 2 files changed, 46 insertions(+), 32 deletions(-)