On 2023/12/11 22:07, Yu Kuai wrote:
> From: Yu Kuai <[email protected]>
>
> Avoid to access bd_inode directly, prepare to remove bd_inode from
> block_devcie.
>
> Signed-off-by: Yu Kuai <[email protected]>
> ---
> fs/erofs/data.c | 18 ++++++++++++------
> fs/erofs/internal.h | 2 ++
> 2 files changed, 14 insertions(+), 6 deletions(-)
>
> diff --git a/fs/erofs/data.c b/fs/erofs/data.c
> index c98aeda8abb2..8cf3618190ab 100644
> --- a/fs/erofs/data.c
> +++ b/fs/erofs/data.c
> @@ -32,8 +32,7 @@ void erofs_put_metabuf(struct erofs_buf *buf)
> void *erofs_bread(struct erofs_buf *buf, erofs_blk_t blkaddr,
> enum erofs_kmap_type type)
> {
> - struct inode *inode = buf->inode;
> - erofs_off_t offset = (erofs_off_t)blkaddr << inode->i_blkbits;
> + erofs_off_t offset = (erofs_off_t)blkaddr << buf->blkszbits;
I'd suggest that use `buf->blkszbits` only for bdev_read_folio() since
erofs_init_metabuf() is not always called before erofs_bread() is used.
For example, buf->inode can be one of directory inodes other than
initialized by erofs_init_metabuf().
Thanks,
Gao Xiang
> pgoff_t index = offset >> PAGE_SHIFT;
> struct page *page = buf->page;
> struct folio *folio;
> @@ -43,7 +42,9 @@ void *erofs_bread(struct erofs_buf *buf, erofs_blk_t blkaddr,
> erofs_put_metabuf(buf);
>
> nofs_flag = memalloc_nofs_save();
> - folio = read_cache_folio(inode->i_mapping, index, NULL, NULL);
> + folio = buf->inode ?
> + read_mapping_folio(buf->inode->i_mapping, index, NULL) :
> + bdev_read_folio(buf->bdev, offset);
> memalloc_nofs_restore(nofs_flag);
> if (IS_ERR(folio))
> return folio;
> @@ -67,10 +68,15 @@ void *erofs_bread(struct erofs_buf *buf, erofs_blk_t blkaddr,
>
> void erofs_init_metabuf(struct erofs_buf *buf, struct super_block *sb)
> {
> - if (erofs_is_fscache_mode(sb))
> + if (erofs_is_fscache_mode(sb)) {
> buf->inode = EROFS_SB(sb)->s_fscache->inode;
> - else
> - buf->inode = sb->s_bdev->bd_inode;
> + buf->bdev = NULL;
> + buf->blkszbits = buf->inode->i_blkbits;
> + } else {
> + buf->inode = NULL;
> + buf->bdev = sb->s_bdev;
> + buf->blkszbits = EROFS_SB(sb)->blkszbits;
> + }
> }
>
> void *erofs_read_metabuf(struct erofs_buf *buf, struct super_block *sb,
> diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
> index b0409badb017..c9206351b485 100644
> --- a/fs/erofs/internal.h
> +++ b/fs/erofs/internal.h
> @@ -224,8 +224,10 @@ enum erofs_kmap_type {
>
> struct erofs_buf {
> struct inode *inode;
> + struct block_device *bdev;
> struct page *page;
> void *base;
> + u8 blkszbits;
> enum erofs_kmap_type kmap_type;
> };
> #define __EROFS_BUF_INITIALIZER ((struct erofs_buf){ .page = NULL })
Hi,
在 2023/12/12 14:35, Gao Xiang 写道:
>
>
> On 2023/12/11 22:07, Yu Kuai wrote:
>> From: Yu Kuai <[email protected]>
>>
>> Avoid to access bd_inode directly, prepare to remove bd_inode from
>> block_devcie.
>>
>> Signed-off-by: Yu Kuai <[email protected]>
>> ---
>> fs/erofs/data.c | 18 ++++++++++++------
>> fs/erofs/internal.h | 2 ++
>> 2 files changed, 14 insertions(+), 6 deletions(-)
>>
>> diff --git a/fs/erofs/data.c b/fs/erofs/data.c
>> index c98aeda8abb2..8cf3618190ab 100644
>> --- a/fs/erofs/data.c
>> +++ b/fs/erofs/data.c
>> @@ -32,8 +32,7 @@ void erofs_put_metabuf(struct erofs_buf *buf)
>> void *erofs_bread(struct erofs_buf *buf, erofs_blk_t blkaddr,
>> enum erofs_kmap_type type)
>> {
>> - struct inode *inode = buf->inode;
>> - erofs_off_t offset = (erofs_off_t)blkaddr << inode->i_blkbits;
>> + erofs_off_t offset = (erofs_off_t)blkaddr << buf->blkszbits;
> I'd suggest that use `buf->blkszbits` only for bdev_read_folio() since
> erofs_init_metabuf() is not always called before erofs_bread() is used.
>
> For example, buf->inode can be one of directory inodes other than
> initialized by erofs_init_metabuf().
Thanks for the notice, and you're right, I'll update code in v3:
u8 blkszbits = buf->inode ? inode->i_blkbits : buf->blkszbits;
erofs_off_t offset = (erofs_off_t)blkaddr << blkszbits;
Kuai
>
> Thanks,
> Gao Xiang
>
>
>> pgoff_t index = offset >> PAGE_SHIFT;
>> struct page *page = buf->page;
>> struct folio *folio;
>> @@ -43,7 +42,9 @@ void *erofs_bread(struct erofs_buf *buf, erofs_blk_t
>> blkaddr,
>> erofs_put_metabuf(buf);
>> nofs_flag = memalloc_nofs_save();
>> - folio = read_cache_folio(inode->i_mapping, index, NULL, NULL);
>> + folio = buf->inode ?
>> + read_mapping_folio(buf->inode->i_mapping, index, NULL) :
>> + bdev_read_folio(buf->bdev, offset);
>> memalloc_nofs_restore(nofs_flag);
>> if (IS_ERR(folio))
>> return folio;
>> @@ -67,10 +68,15 @@ void *erofs_bread(struct erofs_buf *buf,
>> erofs_blk_t blkaddr,
>> void erofs_init_metabuf(struct erofs_buf *buf, struct super_block *sb)
>> {
>> - if (erofs_is_fscache_mode(sb))
>> + if (erofs_is_fscache_mode(sb)) {
>> buf->inode = EROFS_SB(sb)->s_fscache->inode;
>> - else
>> - buf->inode = sb->s_bdev->bd_inode;
>> + buf->bdev = NULL;
>> + buf->blkszbits = buf->inode->i_blkbits;
>> + } else {
>> + buf->inode = NULL;
>> + buf->bdev = sb->s_bdev;
>> + buf->blkszbits = EROFS_SB(sb)->blkszbits;
>> + }
>> }
>> void *erofs_read_metabuf(struct erofs_buf *buf, struct super_block *sb,
>> diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
>> index b0409badb017..c9206351b485 100644
>> --- a/fs/erofs/internal.h
>> +++ b/fs/erofs/internal.h
>> @@ -224,8 +224,10 @@ enum erofs_kmap_type {
>> struct erofs_buf {
>> struct inode *inode;
>> + struct block_device *bdev;
>> struct page *page;
>> void *base;
>> + u8 blkszbits;
>> enum erofs_kmap_type kmap_type;
>> };
>> #define __EROFS_BUF_INITIALIZER ((struct erofs_buf){ .page = NULL })
> .
>