[PATCH 0/2] erofs: misc fixes for erofs in fscache mode

[PATCH 0/2] erofs: misc fixes for erofs in fscache mode

[Jingbo Xu]

There are several minor fixes for the data path of the fscache mode.

Jingbo Xu (2):
  erofs: put metabuf in error path in fscache mode
  erofs: get correct count for unmapped range in fscache mode

 fs/erofs/fscache.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

-- 
2.19.1.6.gb485710b

[PATCH 1/2] erofs: put metabuf in error path in fscache mode

[Jingbo Xu]

For tail packing layout, put metabuf when error is encountered.

Fixes: 1ae9470c3e14 ("erofs: clean up .read_folio() and .readahead() in fscache mode")
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
---
 fs/erofs/fscache.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c
index fe05bc51f9f2..83559008bfa8 100644
--- a/fs/erofs/fscache.c
+++ b/fs/erofs/fscache.c
@@ -287,8 +287,10 @@ static int erofs_fscache_data_read(struct address_space *mapping,
 			return PTR_ERR(src);
 
 		iov_iter_xarray(&iter, READ, &mapping->i_pages, pos, PAGE_SIZE);
-		if (copy_to_iter(src + offset, size, &iter) != size)
+		if (copy_to_iter(src + offset, size, &iter) != size) {
+			erofs_put_metabuf(&buf);
 			return -EFAULT;
+		}
 		iov_iter_zero(PAGE_SIZE - size, &iter);
 		erofs_put_metabuf(&buf);
 		return PAGE_SIZE;
-- 
2.19.1.6.gb485710b

Re: [PATCH 1/2] erofs: put metabuf in error path in fscache mode

[Gao Xiang]

On Fri, Nov 04, 2022 at 01:40:27PM +0800, Jingbo Xu wrote:
> For tail packing layout, put metabuf when error is encountered.
> 
> Fixes: 1ae9470c3e14 ("erofs: clean up .read_folio() and .readahead() in fscache mode")
> Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>

Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>

Thanks,
Gao Xiang

> ---
>  fs/erofs/fscache.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c
> index fe05bc51f9f2..83559008bfa8 100644
> --- a/fs/erofs/fscache.c
> +++ b/fs/erofs/fscache.c
> @@ -287,8 +287,10 @@ static int erofs_fscache_data_read(struct address_space *mapping,
>  			return PTR_ERR(src);
>  
>  		iov_iter_xarray(&iter, READ, &mapping->i_pages, pos, PAGE_SIZE);
> -		if (copy_to_iter(src + offset, size, &iter) != size)
> +		if (copy_to_iter(src + offset, size, &iter) != size) {
> +			erofs_put_metabuf(&buf);
>  			return -EFAULT;
> +		}
>  		iov_iter_zero(PAGE_SIZE - size, &iter);
>  		erofs_put_metabuf(&buf);
>  		return PAGE_SIZE;
> -- 
> 2.19.1.6.gb485710b

Re: [External] [PATCH 1/2] erofs: put metabuf in error path in fscache mode

[Jia Zhu]

在 2022/11/4 13:40, Jingbo Xu 写道:
> For tail packing layout, put metabuf when error is encountered.
> 
> Fixes: 1ae9470c3e14 ("erofs: clean up .read_folio() and .readahead() in fscache mode")
> Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
> ---
>   fs/erofs/fscache.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c
> index fe05bc51f9f2..83559008bfa8 100644
> --- a/fs/erofs/fscache.c
> +++ b/fs/erofs/fscache.c
> @@ -287,8 +287,10 @@ static int erofs_fscache_data_read(struct address_space *mapping,
>   			return PTR_ERR(src);
>   
>   		iov_iter_xarray(&iter, READ, &mapping->i_pages, pos, PAGE_SIZE);
> -		if (copy_to_iter(src + offset, size, &iter) != size)
> +		if (copy_to_iter(src + offset, size, &iter) != size) {
> +			erofs_put_metabuf(&buf);
>   			return -EFAULT;
> +		}
>   		iov_iter_zero(PAGE_SIZE - size, &iter);
>   		erofs_put_metabuf(&buf);
>   		return PAGE_SIZE;

Re: [PATCH 1/2] erofs: put metabuf in error path in fscache mode

[Chao Yu]

On 2022/11/4 13:40, Jingbo Xu wrote:
> For tail packing layout, put metabuf when error is encountered.
> 
> Fixes: 1ae9470c3e14 ("erofs: clean up .read_folio() and .readahead() in fscache mode")
> Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>

Reviewed-by: Chao Yu <chao@kernel.org>

Thanks,

[PATCH 2/2] erofs: get correct count for unmapped range in fscache mode

[Jingbo Xu]

For unmapped range, the returned map.m_llen is zero, and thus the
calculated count is unexpected zero.

Prior to the refactoring introduced by commit 1ae9470c3e14 ("erofs:
clean up .read_folio() and .readahead() in fscache mode"), only the
readahead routine suffers from this. With the refactoring of making
.read_folio() and .readahead() calling one common routine, both
read_folio and readahead have this issue now.

Fix this by calculating count separately in unmapped condition.

Fixes: c665b394b9e8 ("erofs: implement fscache-based data readahead")
Fixes: 1ae9470c3e14 ("erofs: clean up .read_folio() and .readahead() in fscache mode")
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
---
 fs/erofs/fscache.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c
index 83559008bfa8..260fa4737fc0 100644
--- a/fs/erofs/fscache.c
+++ b/fs/erofs/fscache.c
@@ -296,15 +296,16 @@ static int erofs_fscache_data_read(struct address_space *mapping,
 		return PAGE_SIZE;
 	}
 
-	count = min_t(size_t, map.m_llen - (pos - map.m_la), len);
-	DBG_BUGON(!count || count % PAGE_SIZE);
-
 	if (!(map.m_flags & EROFS_MAP_MAPPED)) {
+		count = len;
 		iov_iter_xarray(&iter, READ, &mapping->i_pages, pos, count);
 		iov_iter_zero(count, &iter);
 		return count;
 	}
 
+	count = min_t(size_t, map.m_llen - (pos - map.m_la), len);
+	DBG_BUGON(!count || count % PAGE_SIZE);
+
 	mdev = (struct erofs_map_dev) {
 		.m_deviceid = map.m_deviceid,
 		.m_pa = map.m_pa,
-- 
2.19.1.6.gb485710b

Re: [PATCH 2/2] erofs: get correct count for unmapped range in fscache mode

[Gao Xiang]

On Fri, Nov 04, 2022 at 01:40:28PM +0800, Jingbo Xu wrote:
> For unmapped range, the returned map.m_llen is zero, and thus the
> calculated count is unexpected zero.
> 
> Prior to the refactoring introduced by commit 1ae9470c3e14 ("erofs:
> clean up .read_folio() and .readahead() in fscache mode"), only the
> readahead routine suffers from this. With the refactoring of making
> .read_folio() and .readahead() calling one common routine, both
> read_folio and readahead have this issue now.
> 
> Fix this by calculating count separately in unmapped condition.
> 
> Fixes: c665b394b9e8 ("erofs: implement fscache-based data readahead")
> Fixes: 1ae9470c3e14 ("erofs: clean up .read_folio() and .readahead() in fscache mode")
> Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>

Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>

Thanks,
Gao Xiang

> ---
>  fs/erofs/fscache.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c
> index 83559008bfa8..260fa4737fc0 100644
> --- a/fs/erofs/fscache.c
> +++ b/fs/erofs/fscache.c
> @@ -296,15 +296,16 @@ static int erofs_fscache_data_read(struct address_space *mapping,
>  		return PAGE_SIZE;
>  	}
>  
> -	count = min_t(size_t, map.m_llen - (pos - map.m_la), len);
> -	DBG_BUGON(!count || count % PAGE_SIZE);
> -
>  	if (!(map.m_flags & EROFS_MAP_MAPPED)) {
> +		count = len;
>  		iov_iter_xarray(&iter, READ, &mapping->i_pages, pos, count);
>  		iov_iter_zero(count, &iter);
>  		return count;
>  	}
>  
> +	count = min_t(size_t, map.m_llen - (pos - map.m_la), len);
> +	DBG_BUGON(!count || count % PAGE_SIZE);
> +
>  	mdev = (struct erofs_map_dev) {
>  		.m_deviceid = map.m_deviceid,
>  		.m_pa = map.m_pa,
> -- 
> 2.19.1.6.gb485710b

Re: [PATCH 2/2] erofs: get correct count for unmapped range in fscache mode

[Chao Yu]

On 2022/11/4 13:40, Jingbo Xu wrote:
> For unmapped range, the returned map.m_llen is zero, and thus the
> calculated count is unexpected zero.
> 
> Prior to the refactoring introduced by commit 1ae9470c3e14 ("erofs:
> clean up .read_folio() and .readahead() in fscache mode"), only the
> readahead routine suffers from this. With the refactoring of making
> .read_folio() and .readahead() calling one common routine, both
> read_folio and readahead have this issue now.
> 
> Fix this by calculating count separately in unmapped condition.
> 
> Fixes: c665b394b9e8 ("erofs: implement fscache-based data readahead")
> Fixes: 1ae9470c3e14 ("erofs: clean up .read_folio() and .readahead() in fscache mode")
> Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>

Reviewed-by: Chao Yu <chao@kernel.org>

Thanks,