[v2,1/2] erofs: cleanup erofs_iget()

Message ID 20230114015812.96836-1-hsiangkao@linux.alibaba.com
State New
Headers
Series [v2,1/2] erofs: cleanup erofs_iget() |

Commit Message

Gao Xiang Jan. 14, 2023, 1:58 a.m. UTC
  Move inode hash function into inode.c and simplify erofs_iget().
No logic changes.

Reviewed-by: Yue Hu <huyue2@coolpad.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
---
changes since v1:
 - use ino ^= nid >> sizeof(ino_t) * 8 as suggested by Jingbo.

 fs/erofs/inode.c    | 40 +++++++++++++++++++++-------------------
 fs/erofs/internal.h |  9 ---------
 2 files changed, 21 insertions(+), 28 deletions(-)
  

Comments

kernel test robot Jan. 14, 2023, 3:59 a.m. UTC | #1
Hi Gao,

I love your patch! Perhaps something to improve:

[auto build test WARNING on xiang-erofs/dev-test]
[also build test WARNING on xiang-erofs/dev xiang-erofs/fixes linus/master v6.2-rc3 next-20230113]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Gao-Xiang/erofs-remove-linux-buffer_head-h-dependency/20230114-100018
base:   https://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.git dev-test
patch link:    https://lore.kernel.org/r/20230114015812.96836-1-hsiangkao%40linux.alibaba.com
patch subject: [PATCH v2 1/2] erofs: cleanup erofs_iget()
config: ia64-allyesconfig
compiler: ia64-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/ede350f68141cc6bdc88c627e0f8f992f1b26307
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Gao-Xiang/erofs-remove-linux-buffer_head-h-dependency/20230114-100018
        git checkout ede350f68141cc6bdc88c627e0f8f992f1b26307
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=ia64 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=ia64 SHELL=/bin/bash fs/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

   fs/erofs/inode.c: In function 'erofs_squash_ino':
>> fs/erofs/inode.c:319:28: warning: right shift count >= width of type [-Wshift-count-overflow]
     319 |                 ino ^= nid >> sizeof(ino_t) * 8;
         |                            ^~


vim +319 fs/erofs/inode.c

   309	
   310	/*
   311	 * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down
   312	 * so that it will fit.
   313	 */
   314	static ino_t erofs_squash_ino(erofs_nid_t nid)
   315	{
   316		ino_t ino = (ino_t)nid;
   317	
   318		if (sizeof(ino_t) < sizeof(erofs_nid_t))
 > 319			ino ^= nid >> sizeof(ino_t) * 8;
   320		return ino;
   321	}
   322
  
Gao Xiang Jan. 14, 2023, 4:13 a.m. UTC | #2
On Sat, Jan 14, 2023 at 11:59:41AM +0800, kernel test robot wrote:
> Hi Gao,
> 
> I love your patch! Perhaps something to improve:
> 
> [auto build test WARNING on xiang-erofs/dev-test]
> [also build test WARNING on xiang-erofs/dev xiang-erofs/fixes linus/master v6.2-rc3 next-20230113]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use '--base' as documented in
> https://git-scm.com/docs/git-format-patch#_base_tree_information]
> 
> url:    https://github.com/intel-lab-lkp/linux/commits/Gao-Xiang/erofs-remove-linux-buffer_head-h-dependency/20230114-100018
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.git dev-test
> patch link:    https://lore.kernel.org/r/20230114015812.96836-1-hsiangkao%40linux.alibaba.com
> patch subject: [PATCH v2 1/2] erofs: cleanup erofs_iget()
> config: ia64-allyesconfig
> compiler: ia64-linux-gcc (GCC) 12.1.0
> reproduce (this is a W=1 build):
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # https://github.com/intel-lab-lkp/linux/commit/ede350f68141cc6bdc88c627e0f8f992f1b26307
>         git remote add linux-review https://github.com/intel-lab-lkp/linux
>         git fetch --no-tags linux-review Gao-Xiang/erofs-remove-linux-buffer_head-h-dependency/20230114-100018
>         git checkout ede350f68141cc6bdc88c627e0f8f992f1b26307
>         # save the config file
>         mkdir build_dir && cp config build_dir/.config
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=ia64 olddefconfig
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=ia64 SHELL=/bin/bash fs/
> 
> If you fix the issue, kindly add following tag where applicable
> | Reported-by: kernel test robot <lkp@intel.com>
> 
> All warnings (new ones prefixed by >>):
> 
>    fs/erofs/inode.c: In function 'erofs_squash_ino':
> >> fs/erofs/inode.c:319:28: warning: right shift count >= width of type [-Wshift-count-overflow]
>      319 |                 ino ^= nid >> sizeof(ino_t) * 8;
>          |                            ^~

Okay, I think I have to stick to v1 since v2 causes a
compile warning.

Thanks,
Gao Xiang
  

Patch

diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
index d3b8736fa124..f3b6782c6c53 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(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;