[PATCH 7/8] btrfs: Remove btrfs_dio_data

Goldwyn Rodrigues
2019-12-05T15:56:54Z

From: Goldwyn Rodrigues <rgoldwyn@suse.com>

Since, we are using iomap, we don't get multiple calls for get_blocks(),
and there is no incomplete ordered extents. So, remove btrfs_dio_data
and all its manipulations. The bonus is we don't abuse
current->journal_info anymore.

This reverts f28a49287817 ("Btrfs: fix leaking of ordered extents after
direct IO write error")

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
---
fs/btrfs/inode.c | 76 +++-----------------------------------------------------
1 file changed, 3 insertions(+), 73 deletions(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index f619b5f6a095..fedbbcf108cf 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -56,13 +56,6 @@ struct btrfs_iget_args {
struct btrfs_root *root;
};

-struct btrfs_dio_data {
- u64 reserve;
- u64 unsubmitted_oe_range_start;
- u64 unsubmitted_oe_range_end;
- int overwrite;
-};
-
static const struct inode_operations btrfs_dir_inode_operations;
static const struct inode_operations btrfs_symlink_inode_operations;
static const struct inode_operations btrfs_dir_ro_inode_operations;
@@ -7622,7 +7615,6 @@ static struct extent_map *create_io_em(struct inode *inode, u64 start, u64 len,

static int btrfs_get_blocks_direct_write(struct extent_map **map,
struct inode *inode,
- struct btrfs_dio_data *dio_data,
u64 start, u64 len)
{
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
@@ -7696,13 +7688,9 @@ static int btrfs_get_blocks_direct_write(struct extent_map **map,
* Need to update the i_size under the extent lock so buffered
* readers will get the updated i_size when we unlock.
*/
- if (!dio_data->overwrite && start + len > i_size_read(inode))
+ if (start + len > i_size_read(inode))
i_size_write(inode, start + len);

- WARN_ON(dio_data->reserve < len);
- dio_data->reserve -= len;
- dio_data->unsubmitted_oe_range_end = start + len;
- current->journal_info = dio_data;
out:
return ret;
}
@@ -7714,7 +7702,6 @@ static int btrfs_dio_iomap_begin(struct inode *inode, loff_t start,
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct extent_map *em;
struct extent_state *cached_state = NULL;
- struct btrfs_dio_data *dio_data = NULL;
u64 lockstart, lockend;
bool write = !!(flags & IOMAP_WRITE);
int ret = 0;
@@ -7738,16 +7725,6 @@ static int btrfs_dio_iomap_begin(struct inode *inode, loff_t start,
ret = filemap_fdatawrite_range(inode->i_mapping, start,
start + length - 1);

- if (current->journal_info) {
- /*
- * Need to pull our outstanding extents and set journal_info to NULL so
- * that anything that needs to check if there's a transaction doesn't get
- * confused.
- */
- dio_data = current->journal_info;
- current->journal_info = NULL;
- }
-
/*
* If this errors out it's because we couldn't invalidate pagecache for
* this range and we need to fallback to buffered.
@@ -7788,7 +7765,7 @@ static int btrfs_dio_iomap_begin(struct inode *inode, loff_t start,
len = min(len, em->len - (start - em->start));
if (write) {
ret = btrfs_get_blocks_direct_write(&em, inode,
- dio_data, start, len);
+ start, len);
if (ret < 0)
goto unlock_err;
unlock_extents = true;
@@ -7840,8 +7817,6 @@ static int btrfs_dio_iomap_begin(struct inode *inode, loff_t start,
unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
&cached_state);
err:
- if (dio_data)
- current->journal_info = dio_data;
return ret;
}

@@ -8531,21 +8506,6 @@ static blk_qc_t btrfs_submit_direct(struct bio *dio_bio, struct file *file,
dip->subio_endio = btrfs_subio_endio_read;
}

- /*
- * Reset the range for unsubmitted ordered extents (to a 0 length range)
- * even if we fail to submit a bio, because in such case we do the
- * corresponding error handling below and it must not be done a second
- * time by btrfs_direct_IO().
- */
- if (write) {
- struct btrfs_dio_data *dio_data = current->journal_info;
-
- dio_data->unsubmitted_oe_range_end = dip->logical_offset +
- dip->bytes;
- dio_data->unsubmitted_oe_range_start =
- dio_data->unsubmitted_oe_range_end;
- }
-
ret = btrfs_submit_direct_hook(dip);
if (!ret)
return BLK_QC_T_NONE;
@@ -8648,7 +8608,6 @@ ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
struct file *file = iocb->ki_filp;
struct inode *inode = file->f_mapping->host;
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
- struct btrfs_dio_data dio_data = { 0 };
struct extent_changeset *data_reserved = NULL;
loff_t offset = iocb->ki_pos;
size_t count = 0;
@@ -8666,7 +8625,6 @@ ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
* not unlock the i_mutex at this case.
*/
if (offset + count <= inode->i_size) {
- dio_data.overwrite = 1;
inode_unlock(inode);
relock = true;
} else if (iocb->ki_flags & IOCB_NOWAIT) {
@@ -8678,16 +8636,6 @@ ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
if (ret)
goto out;

- /*
- * We need to know how many extents we reserved so that we can
- * do the accounting properly if we go over the number we
- * originally calculated. Abuse current->journal_info for this.
- */
- dio_data.reserve = round_up(count,
- fs_info->sectorsize);
- dio_data.unsubmitted_oe_range_start = (u64)offset;
- dio_data.unsubmitted_oe_range_end = (u64)offset;
- current->journal_info = &dio_data;
down_read(&BTRFS_I(inode)->dio_sem);
}

@@ -8696,25 +8644,7 @@ ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)

if (iov_iter_rw(iter) == WRITE) {
up_read(&BTRFS_I(inode)->dio_sem);
- current->journal_info = NULL;
- if (ret < 0 && ret != -EIOCBQUEUED) {
- if (dio_data.reserve)
- btrfs_delalloc_release_space(inode, data_reserved,
- offset, dio_data.reserve, true);
- /*
- * On error we might have left some ordered extents
- * without submitting corresponding bios for them, so
- * cleanup them up to avoid other tasks getting them
- * and waiting for them to complete forever.
- */
- if (dio_data.unsubmitted_oe_range_start <
- dio_data.unsubmitted_oe_range_end)
- __endio_write_update_ordered(inode,
- dio_data.unsubmitted_oe_range_start,
- dio_data.unsubmitted_oe_range_end -
- dio_data.unsubmitted_oe_range_start,
- false);
- } else if (ret >= 0 && (size_t)ret < count)
+ if (ret >= 0 && (size_t)ret < count)
btrfs_delalloc_release_space(inode, data_reserved,
offset, count - (size_t)ret, true);
btrfs_delalloc_release_extents(BTRFS_I(inode), count);
--
2.16.4