[PATCH 2/5] xfs: fold xfs_attr_get_int into xfs_attr_get

Christoph Hellwig
2014-05-03T15:18:04Z

This allows doing an unlocked check if an attr for is present at all and
slightly reduce the lock hold time if we actually do an attr get.

Plus various minor style fixes to the new xfs_attr_get.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/xfs/xfs_attr.c | 79 ++++++++++++++++++-----------------------------------
1 file changed, 27 insertions(+), 52 deletions(-)

diff --git a/fs/xfs/xfs_attr.c b/fs/xfs/xfs_attr.c
index eb3ae8f..01f2267 100644
--- a/fs/xfs/xfs_attr.c
+++ b/fs/xfs/xfs_attr.c
@@ -106,26 +106,34 @@ xfs_inode_hasattr(
* Overall external interface routines.
*========================================================================*/

-STATIC int
-xfs_attr_get_int(
+int
+xfs_attr_get(
struct xfs_inode *ip,
- struct xfs_name *name,
+ const unsigned char *name,
unsigned char *value,
int *valuelenp,
int flags)
{
- xfs_da_args_t args;
- int error;
+ struct xfs_da_args args;
+ struct xfs_name xname;
+ uint lock_mode;
+ int error;
+
+ XFS_STATS_INC(xs_attr_get);
+
+ if (XFS_FORCED_SHUTDOWN(ip->i_mount))
+ return EIO;

if (!xfs_inode_hasattr(ip))
return ENOATTR;

- /*
- * Fill in the arg structure for this request.
- */
- memset((char *)&args, 0, sizeof(args));
- args.name = name->name;
- args.namelen = name->len;
+ error = xfs_attr_name_to_xname(&xname, name);
+ if (error)
+ return error;
+
+ memset(&args, 0, sizeof(args));
+ args.name = xname.name;
+ args.namelen = xname.len;
args.value = value;
args.valuelen = *valuelenp;
args.flags = flags;
@@ -133,52 +141,19 @@ xfs_attr_get_int(
args.dp = ip;
args.whichfork = XFS_ATTR_FORK;

- /*
- * Decide on what work routines to call based on the inode size.
- */
- if (ip->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
+ lock_mode = xfs_ilock_attr_map_shared(ip);
+ if (!xfs_inode_hasattr(ip))
+ error = ENOATTR;
+ else if (ip->i_d.di_aformat == XFS_DINODE_FMT_LOCAL)
error = xfs_attr_shortform_getvalue(&args);
- } else if (xfs_bmap_one_block(ip, XFS_ATTR_FORK)) {
+ else if (xfs_bmap_one_block(ip, XFS_ATTR_FORK))
error = xfs_attr_leaf_get(&args);
- } else {
+ else
error = xfs_attr_node_get(&args);
- }
+ xfs_iunlock(ip, lock_mode);

- /*
- * Return the number of bytes in the value to the caller.
- */
*valuelenp = args.valuelen;
-
- if (error == EEXIST)
- error = 0;
- return(error);
-}
-
-int
-xfs_attr_get(
- xfs_inode_t *ip,
- const unsigned char *name,
- unsigned char *value,
- int *valuelenp,
- int flags)
-{
- int error;
- struct xfs_name xname;
- uint lock_mode;
-
- XFS_STATS_INC(xs_attr_get);
-
- if (XFS_FORCED_SHUTDOWN(ip->i_mount))
- return(EIO);
-
- error = xfs_attr_name_to_xname(&xname, name);
- if (error)
- return error;
-
- lock_mode = xfs_ilock_attr_map_shared(ip);
- error = xfs_attr_get_int(ip, &xname, value, valuelenp, flags);
- xfs_iunlock(ip, lock_mode);
- return(error);
+ return error == EEXIST ? 0 : error;
}

/*
--
1.7.10.4