[PATCH 1/2] btrfs: returns -ENOMEM if path allocation failed in btrfs_cross_ref_exist()

[PATCH 1/2] btrfs: returns -ENOMEM if path allocation failed in btrfs_cross_ref_exist()

[Su Yue]

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
---
 fs/btrfs/extent-tree.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 44093f92a532..99df6199dffc 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3311,7 +3311,7 @@ int btrfs_cross_ref_exist(struct btrfs_root *root, u64 objectid, u64 offset,
 
 	path = btrfs_alloc_path();
 	if (!path)
-		return -ENOENT;
+		return -ENOMEM;
 
 	do {
 		ret = check_committed_ref(root, path, objectid,
-- 
2.17.0

Re: [PATCH 1/2] btrfs: returns -ENOMEM if path allocation failed in btrfs_cross_ref_exist()

[Su Yue]

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Sorry, the [PATCH 2/2] is abandoned. So the subject should be [PATCH].


On 05/30/2018 10:07 AM, Su Yue wrote:
> Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
> ---
>  fs/btrfs/extent-tree.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
> index 44093f92a532..99df6199dffc 100644
> --- a/fs/btrfs/extent-tree.c
> +++ b/fs/btrfs/extent-tree.c
> @@ -3311,7 +3311,7 @@ int btrfs_cross_ref_exist(struct btrfs_root *root, u64 objectid, u64 offset,
>  
>  	path = btrfs_alloc_path();
>  	if (!path)
> -		return -ENOENT;
> +		return -ENOMEM;
>  
>  	do {
>  		ret = check_committed_ref(root, path, objectid,
> 



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Re: [PATCH 1/2] btrfs: returns -ENOMEM if path allocation failed in btrfs_cross_ref_exist()

[Nikolay Borisov]

On 30.05.2018 05:07, Su Yue wrote:
> Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>

Generally we discourage commit log messages. I understand this patch is
very obvious but put a sentence saying that btrfs_alloc_path can fail
due to enomem hence returning enomem is the right ting to do here.
> ---
>  fs/btrfs/extent-tree.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
> index 44093f92a532..99df6199dffc 100644
> --- a/fs/btrfs/extent-tree.c
> +++ b/fs/btrfs/extent-tree.c
> @@ -3311,7 +3311,7 @@ int btrfs_cross_ref_exist(struct btrfs_root *root, u64 objectid, u64 offset,
>  
>  	path = btrfs_alloc_path();
>  	if (!path)
> -		return -ENOENT;
> +		return -ENOMEM;
>  
>  	do {
>  		ret = check_committed_ref(root, path, objectid,
> 

[PATCH v2] btrfs: returns -ENOMEM if path allocation failed in btrfs_cross_ref_exist()

[Su Yue]

btrfs_alloc_path() may fail due to no enough memory,
so let the function return -ENOMEM instead of -ENOENT is better.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
---
Changelog:
v2:
  Add commit message to describe the patch. Thanks Nikolay.
  
 fs/btrfs/extent-tree.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 44093f92a532..99df6199dffc 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3311,7 +3311,7 @@ int btrfs_cross_ref_exist(struct btrfs_root *root, u64 objectid, u64 offset,
 
 	path = btrfs_alloc_path();
 	if (!path)
-		return -ENOENT;
+		return -ENOMEM;
 
 	do {
 		ret = check_committed_ref(root, path, objectid,
-- 
2.17.0

Re: [PATCH v2] btrfs: returns -ENOMEM if path allocation failed in btrfs_cross_ref_exist()

[Nikolay Borisov]

On 30.05.2018 09:49, Su Yue wrote:
> btrfs_alloc_path() may fail due to no enough memory,
> so let the function return -ENOMEM instead of -ENOENT is better.
> 
> Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
> ---
> Changelog:
> v2:
>   Add commit message to describe the patch. Thanks Nikolay.
>   
>  fs/btrfs/extent-tree.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
> index 44093f92a532..99df6199dffc 100644
> --- a/fs/btrfs/extent-tree.c
> +++ b/fs/btrfs/extent-tree.c
> @@ -3311,7 +3311,7 @@ int btrfs_cross_ref_exist(struct btrfs_root *root, u64 objectid, u64 offset,
>  
>  	path = btrfs_alloc_path();
>  	if (!path)
> -		return -ENOENT;
> +		return -ENOMEM;
>  
>  	do {
>  		ret = check_committed_ref(root, path, objectid,
> 

Re: [PATCH v2] btrfs: returns -ENOMEM if path allocation failed in btrfs_cross_ref_exist()

[David Sterba]

On Wed, May 30, 2018 at 02:49:10PM +0800, Su Yue wrote:
> btrfs_alloc_path() may fail due to no enough memory,
> so let the function return -ENOMEM instead of -ENOENT is better.
> 
> Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>

Reviewed-by: David Sterba <dsterba@suse.com>

Thanks. I've audited all return codes after failed path allocation, this
was the only one not matching.

The return code of btrfs_cross_ref_exist should be also distinguished at
the call sites, as both places expect only the ENOENT but should not
react to ENOMEM as if it were ENOENT.

Re: [PATCH v2] btrfs: returns -ENOMEM if path allocation failed in btrfs_cross_ref_exist()

[Su Yue]

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On 05/30/2018 11:33 PM, David Sterba wrote:
> On Wed, May 30, 2018 at 02:49:10PM +0800, Su Yue wrote:
>> btrfs_alloc_path() may fail due to no enough memory,
>> so let the function return -ENOMEM instead of -ENOENT is better.
>>
>> Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
> 
> Reviewed-by: David Sterba <dsterba@suse.com>
> 
> Thanks. I've audited all return codes after failed path allocation, this
> was the only one not matching.
> 
> The return code of btrfs_cross_ref_exist should be also distinguished at
> the call sites, as both places expect only the ENOENT but should not
> react to ENOMEM as if it were ENOENT.
> 
Not quite understand the last paragraph. Is necessary to send patches to
make the two callers to distinguish ENOMEM and ENOENT?

Thanks,
Su

> 



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