Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
rpc_pipe: don't overdo directory locking
Don't try to hold directories locked more than VFS requires;
lock just before getting a child to be made positive (using
simple_start_creating()) and unlock as soon as the child is
created. There's no benefit in keeping the parent locked
while populating the child - it won't stop dcache lookups anyway.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
+9
-35
+9
-35
net/sunrpc/rpc_pipe.c
+9
-35
net/sunrpc/rpc_pipe.c
···
594
594
return 0;
595
595
}
596
596
597
-
static struct dentry *__rpc_lookup_create_exclusive(struct dentry *parent,
598
-
const char *name)
599
-
{
600
-
struct qstr q = QSTR(name);
601
-
struct dentry *dentry = try_lookup_noperm(&q, parent);
602
-
if (!dentry) {
603
-
dentry = d_alloc(parent, &q);
604
-
if (!dentry)
605
-
return ERR_PTR(-ENOMEM);
606
-
}
607
-
if (d_really_is_negative(dentry))
608
-
return dentry;
609
-
dput(dentry);
610
-
return ERR_PTR(-EEXIST);
611
-
}
612
-
613
597
static int rpc_populate(struct dentry *parent,
614
598
const struct rpc_filelist *files,
615
599
int start, int eof,
···
603
619
struct dentry *dentry;
604
620
int i, err;
605
621
606
-
inode_lock(dir);
607
622
for (i = start; i < eof; i++) {
608
-
dentry = __rpc_lookup_create_exclusive(parent, files[i].name);
623
+
dentry = simple_start_creating(parent, files[i].name);
609
624
err = PTR_ERR(dentry);
610
625
if (IS_ERR(dentry))
611
626
goto out_bad;
···
616
633
files[i].mode,
617
634
files[i].i_fop,
618
635
private);
636
+
inode_unlock(dir);
619
637
break;
620
638
case S_IFDIR:
621
639
err = __rpc_mkdir(dir, dentry,
622
640
files[i].mode,
623
641
NULL,
624
642
private);
643
+
inode_unlock(dir);
625
644
}
626
645
if (err != 0)
627
646
goto out_bad;
628
647
}
629
-
inode_unlock(dir);
630
648
return 0;
631
649
out_bad:
632
-
inode_unlock(dir);
633
650
printk(KERN_WARNING "%s: %s failed to populate directory %pd\n",
634
651
__FILE__, __func__, parent);
635
652
return err;
···
643
660
struct inode *dir = d_inode(parent);
644
661
int error;
645
662
646
-
inode_lock_nested(dir, I_MUTEX_PARENT);
647
-
dentry = __rpc_lookup_create_exclusive(parent, name);
663
+
dentry = simple_start_creating(parent, name);
648
664
if (IS_ERR(dentry))
649
-
goto out;
665
+
return dentry;
650
666
error = __rpc_mkdir(dir, dentry, mode, NULL, private);
667
+
inode_unlock(dir);
651
668
if (error != 0)
652
-
goto out_err;
669
+
return ERR_PTR(error);
653
670
if (populate != NULL) {
654
671
error = populate(dentry, args_populate);
655
672
if (error) {
656
-
inode_unlock(dir);
657
673
simple_recursive_removal(dentry, NULL);
658
674
return ERR_PTR(error);
659
675
}
660
676
}
661
-
out:
662
-
inode_unlock(dir);
663
677
return dentry;
664
-
out_err:
665
-
dentry = ERR_PTR(error);
666
-
goto out;
667
678
}
668
679
669
680
/**
···
692
715
if (pipe->ops->downcall == NULL)
693
716
umode &= ~0222;
694
717
695
-
inode_lock_nested(dir, I_MUTEX_PARENT);
696
-
dentry = __rpc_lookup_create_exclusive(parent, name);
697
-
if (IS_ERR(dentry)) {
698
-
inode_unlock(dir);
718
+
dentry = simple_start_creating(parent, name);
719
+
if (IS_ERR(dentry))
699
720
return PTR_ERR(dentry);
700
-
}
701
721
err = __rpc_mkpipe_dentry(dir, dentry, umode, &rpc_pipe_fops,
702
722
private, pipe);
703
723
if (unlikely(err))