diff mbox series

[1/2] erofs: clean up erofs_iget()

Message ID 20230113065226.68801-1-hsiangkao@linux.alibaba.com
State New
Headers
Series [1/2] erofs: clean up erofs_iget() |

Commit Message

Gao Xiang Jan. 13, 2023, 6:52 a.m. UTC 
  Move inode hash function into inode.c and simplify erofs_iget().

Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
---
 fs/erofs/inode.c    | 40 +++++++++++++++++++++-------------------
 fs/erofs/internal.h |  9 ---------
 2 files changed, 21 insertions(+), 28 deletions(-)

Comments

Yue Hu Jan. 13, 2023, 7:38 a.m. UTC | #1 
On Fri, 13 Jan 2023 14:52:25 +0800
Gao Xiang <hsiangkao@linux.alibaba.com> wrote:

> Move inode hash function into inode.c and simplify erofs_iget().
> 
> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

Reviewed-by: Yue Hu <huyue2@coolpad.com>
Jingbo Xu Jan. 13, 2023, 7:41 a.m. UTC | #2 
On 1/13/23 2:52 PM, Gao Xiang wrote:
> Move inode hash function into inode.c and simplify erofs_iget().
> 
> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
> ---
>  fs/erofs/inode.c    | 40 +++++++++++++++++++++-------------------
>  fs/erofs/internal.h |  9 ---------
>  2 files changed, 21 insertions(+), 28 deletions(-)
> 
> diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
> index d3b8736fa124..57328691582e 100644
> --- a/fs/erofs/inode.c
> +++ b/fs/erofs/inode.c
> @@ -308,47 +308,49 @@ static int erofs_fill_inode(struct inode *inode)
>  }
>  
>  /*
> - * erofs nid is 64bits, but i_ino is 'unsigned long', therefore
> - * we should do more for 32-bit platform to find the right inode.
> + * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down
> + * so that it will fit.
>   */
> -static int erofs_ilookup_test_actor(struct inode *inode, void *opaque)
> +static ino_t erofs_squash_ino(erofs_nid_t nid)
>  {
> -	const erofs_nid_t nid = *(erofs_nid_t *)opaque;
> +	ino_t ino = (ino_t)nid;
> +
> +	if (sizeof(ino_t) < sizeof(erofs_nid_t))
> +		ino ^= nid >> (sizeof(erofs_nid_t) - sizeof(ino_t)) * 8;

Shouldn't we do:

	ino ^= nid >> sizeof(ino_t) * 8
?
Gao Xiang Jan. 13, 2023, 7:46 a.m. UTC | #3 
On 2023/1/13 15:41, Jingbo Xu wrote:
> 
> 
> On 1/13/23 2:52 PM, Gao Xiang wrote:
>> Move inode hash function into inode.c and simplify erofs_iget().
>>
>> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
>> ---
>>   fs/erofs/inode.c    | 40 +++++++++++++++++++++-------------------
>>   fs/erofs/internal.h |  9 ---------
>>   2 files changed, 21 insertions(+), 28 deletions(-)
>>
>> diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
>> index d3b8736fa124..57328691582e 100644
>> --- a/fs/erofs/inode.c
>> +++ b/fs/erofs/inode.c
>> @@ -308,47 +308,49 @@ static int erofs_fill_inode(struct inode *inode)
>>   }
>>   
>>   /*
>> - * erofs nid is 64bits, but i_ino is 'unsigned long', therefore
>> - * we should do more for 32-bit platform to find the right inode.
>> + * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down
>> + * so that it will fit.
>>    */
>> -static int erofs_ilookup_test_actor(struct inode *inode, void *opaque)
>> +static ino_t erofs_squash_ino(erofs_nid_t nid)
>>   {
>> -	const erofs_nid_t nid = *(erofs_nid_t *)opaque;
>> +	ino_t ino = (ino_t)nid;
>> +
>> +	if (sizeof(ino_t) < sizeof(erofs_nid_t))
>> +		ino ^= nid >> (sizeof(erofs_nid_t) - sizeof(ino_t)) * 8;
> 
> Shouldn't we do:
> 
> 	ino ^= nid >> sizeof(ino_t) * 8
Actually I copied it from fuse, for 64-bit erofs_nid_t it has no difference
though. I will also update it as your suggestion in v2.

Thanks,
Gao Xiang


> ?
> 
>
Jingbo Xu Jan. 14, 2023, 8:21 a.m. UTC | #4 
On 1/13/23 2:52 PM, Gao Xiang wrote:
> Move inode hash function into inode.c and simplify erofs_iget().
> 
> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

Since the v2 triggers the compiling error, this v1 is also acceptable
for me.

Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>

> ---
>  fs/erofs/inode.c    | 40 +++++++++++++++++++++-------------------
>  fs/erofs/internal.h |  9 ---------
>  2 files changed, 21 insertions(+), 28 deletions(-)
> 
> diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
> index d3b8736fa124..57328691582e 100644
> --- a/fs/erofs/inode.c
> +++ b/fs/erofs/inode.c
> @@ -308,47 +308,49 @@ static int erofs_fill_inode(struct inode *inode)
>  }
>  
>  /*
> - * erofs nid is 64bits, but i_ino is 'unsigned long', therefore
> - * we should do more for 32-bit platform to find the right inode.
> + * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down
> + * so that it will fit.
>   */
> -static int erofs_ilookup_test_actor(struct inode *inode, void *opaque)
> +static ino_t erofs_squash_ino(erofs_nid_t nid)
>  {
> -	const erofs_nid_t nid = *(erofs_nid_t *)opaque;
> +	ino_t ino = (ino_t)nid;
> +
> +	if (sizeof(ino_t) < sizeof(erofs_nid_t))
> +		ino ^= nid >> (sizeof(erofs_nid_t) - sizeof(ino_t)) * 8;
> +	return ino;
> +}
>  
> -	return EROFS_I(inode)->nid == nid;
> +static int erofs_iget5_eq(struct inode *inode, void *opaque)
> +{
> +	return EROFS_I(inode)->nid == *(erofs_nid_t *)opaque;
>  }
>  
> -static int erofs_iget_set_actor(struct inode *inode, void *opaque)
> +static int erofs_iget5_set(struct inode *inode, void *opaque)
>  {
>  	const erofs_nid_t nid = *(erofs_nid_t *)opaque;
>  
> -	inode->i_ino = erofs_inode_hash(nid);
> +	inode->i_ino = erofs_squash_ino(nid);
> +	EROFS_I(inode)->nid = nid;
>  	return 0;
>  }
>  
>  struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid)
>  {
> -	const unsigned long hashval = erofs_inode_hash(nid);
>  	struct inode *inode;
>  
> -	inode = iget5_locked(sb, hashval, erofs_ilookup_test_actor,
> -		erofs_iget_set_actor, &nid);
> +	inode = iget5_locked(sb, erofs_squash_ino(nid), erofs_iget5_eq,
> +			     erofs_iget5_set, &nid);
>  	if (!inode)
>  		return ERR_PTR(-ENOMEM);
>  
>  	if (inode->i_state & I_NEW) {
> -		int err;
> -		struct erofs_inode *vi = EROFS_I(inode);
> -
> -		vi->nid = nid;
> +		int err = erofs_fill_inode(inode);
>  
> -		err = erofs_fill_inode(inode);
> -		if (!err) {
> -			unlock_new_inode(inode);
> -		} else {
> +		if (err) {
>  			iget_failed(inode);
> -			inode = ERR_PTR(err);
> +			return ERR_PTR(err);
>  		}
> +		unlock_new_inode(inode);
>  	}
>  	return inode;
>  }
> diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
> index bb8501c0ff5b..168c21f16383 100644
> --- a/fs/erofs/internal.h
> +++ b/fs/erofs/internal.h
> @@ -480,15 +480,6 @@ int erofs_map_blocks(struct inode *inode,
>  		     struct erofs_map_blocks *map, int flags);
>  
>  /* inode.c */
> -static inline unsigned long erofs_inode_hash(erofs_nid_t nid)
> -{
> -#if BITS_PER_LONG == 32
> -	return (nid >> 32) ^ (nid & 0xffffffff);
> -#else
> -	return nid;
> -#endif
> -}
> -
>  extern const struct inode_operations erofs_generic_iops;
>  extern const struct inode_operations erofs_symlink_iops;
>  extern const struct inode_operations erofs_fast_symlink_iops;
Chao Yu Feb. 14, 2023, 1:38 p.m. UTC | #5 
On 2023/1/13 14:52, Gao Xiang wrote:
> Move inode hash function into inode.c and simplify erofs_iget().
> 
> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

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

Thanks,
diff mbox series

Patch

diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
index d3b8736fa124..57328691582e 100644
--- a/fs/erofs/inode.c
+++ b/fs/erofs/inode.c
@@ -308,47 +308,49 @@  static int erofs_fill_inode(struct inode *inode)
 }
 
 /*
- * erofs nid is 64bits, but i_ino is 'unsigned long', therefore
- * we should do more for 32-bit platform to find the right inode.
+ * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down
+ * so that it will fit.
  */
-static int erofs_ilookup_test_actor(struct inode *inode, void *opaque)
+static ino_t erofs_squash_ino(erofs_nid_t nid)
 {
-	const erofs_nid_t nid = *(erofs_nid_t *)opaque;
+	ino_t ino = (ino_t)nid;
+
+	if (sizeof(ino_t) < sizeof(erofs_nid_t))
+		ino ^= nid >> (sizeof(erofs_nid_t) - sizeof(ino_t)) * 8;
+	return ino;
+}
 
-	return EROFS_I(inode)->nid == nid;
+static int erofs_iget5_eq(struct inode *inode, void *opaque)
+{
+	return EROFS_I(inode)->nid == *(erofs_nid_t *)opaque;
 }
 
-static int erofs_iget_set_actor(struct inode *inode, void *opaque)
+static int erofs_iget5_set(struct inode *inode, void *opaque)
 {
 	const erofs_nid_t nid = *(erofs_nid_t *)opaque;
 
-	inode->i_ino = erofs_inode_hash(nid);
+	inode->i_ino = erofs_squash_ino(nid);
+	EROFS_I(inode)->nid = nid;
 	return 0;
 }
 
 struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid)
 {
-	const unsigned long hashval = erofs_inode_hash(nid);
 	struct inode *inode;
 
-	inode = iget5_locked(sb, hashval, erofs_ilookup_test_actor,
-		erofs_iget_set_actor, &nid);
+	inode = iget5_locked(sb, erofs_squash_ino(nid), erofs_iget5_eq,
+			     erofs_iget5_set, &nid);
 	if (!inode)
 		return ERR_PTR(-ENOMEM);
 
 	if (inode->i_state & I_NEW) {
-		int err;
-		struct erofs_inode *vi = EROFS_I(inode);
-
-		vi->nid = nid;
+		int err = erofs_fill_inode(inode);
 
-		err = erofs_fill_inode(inode);
-		if (!err) {
-			unlock_new_inode(inode);
-		} else {
+		if (err) {
 			iget_failed(inode);
-			inode = ERR_PTR(err);
+			return ERR_PTR(err);
 		}
+		unlock_new_inode(inode);
 	}
 	return inode;
 }
diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index bb8501c0ff5b..168c21f16383 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -480,15 +480,6 @@  int erofs_map_blocks(struct inode *inode,
 		     struct erofs_map_blocks *map, int flags);
 
 /* inode.c */
-static inline unsigned long erofs_inode_hash(erofs_nid_t nid)
-{
-#if BITS_PER_LONG == 32
-	return (nid >> 32) ^ (nid & 0xffffffff);
-#else
-	return nid;
-#endif
-}
-
 extern const struct inode_operations erofs_generic_iops;
 extern const struct inode_operations erofs_symlink_iops;
 extern const struct inode_operations erofs_fast_symlink_iops;