staging/lustre/llite: move root_squash from sysfs to debugfs

root_squash control got accidentally moved to sysfs instead of
debugfs, and the write side of it was also broken expecting a
userspace buffer.
It contains both uid and gid values in a single file, so debugfs
is a clear place for it.

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Fixes: c948390f10ccc "fix inconsistencies of root squash feature"
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/lustre/lustre/llite/lproc_llite.c b/drivers/staging/lustre/lustre/llite/lproc_llite.c
index 03682c10fc9e578d08a3eb3bf6850fda65bd3134..f3ee584157e0a80dc54e93245fcbe7265c0fe7a4 100644 (file)
--- a/drivers/staging/lustre/lustre/llite/lproc_llite.c
+++ b/drivers/staging/lustre/lustre/llite/lproc_llite.c
@@ -924,27 +924,29 @@ static ssize_t ll_unstable_stats_seq_write(struct file *file,
 }
 LPROC_SEQ_FOPS(ll_unstable_stats);
 
-static ssize_t root_squash_show(struct kobject *kobj, struct attribute *attr,
-                               char *buf)
+static int ll_root_squash_seq_show(struct seq_file *m, void *v)
 {
-       struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
-                                             ll_kobj);
+       struct super_block *sb = m->private;
+       struct ll_sb_info *sbi = ll_s2sbi(sb);
        struct root_squash_info *squash = &sbi->ll_squash;
 
-       return sprintf(buf, "%u:%u\n", squash->rsi_uid, squash->rsi_gid);
+       seq_printf(m, "%u:%u\n", squash->rsi_uid, squash->rsi_gid);
+       return 0;
 }
 
-static ssize_t root_squash_store(struct kobject *kobj, struct attribute *attr,
-                                const char *buffer, size_t count)
+static ssize_t ll_root_squash_seq_write(struct file *file,
+                                       const char __user *buffer,
+                                       size_t count, loff_t *off)
 {
-       struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
-                                             ll_kobj);
+       struct seq_file *m = file->private_data;
+       struct super_block *sb = m->private;
+       struct ll_sb_info *sbi = ll_s2sbi(sb);
        struct root_squash_info *squash = &sbi->ll_squash;
 
        return lprocfs_wr_root_squash(buffer, count, squash,
-                                     ll_get_fsname(sbi->ll_sb, NULL, 0));
+                                     ll_get_fsname(sb, NULL, 0));
 }
-LUSTRE_RW_ATTR(root_squash);
+LPROC_SEQ_FOPS(ll_root_squash);
 
 static int ll_nosquash_nids_seq_show(struct seq_file *m, void *v)
 {
@@ -997,6 +999,8 @@ static struct lprocfs_vars lprocfs_llite_obd_vars[] = {
        { "statahead_stats",  &ll_statahead_stats_fops, NULL, 0 },
        { "unstable_stats",   &ll_unstable_stats_fops, NULL },
        { "sbi_flags",        &ll_sbi_flags_fops, NULL, 0 },
+       { .name =       "root_squash",
+         .fops =       &ll_root_squash_fops                    },
        { .name =               "nosquash_nids",
          .fops =               &ll_nosquash_nids_fops          },
        { NULL }
@@ -1027,7 +1031,6 @@ static struct attribute *llite_attrs[] = {
        &lustre_attr_max_easize.attr,
        &lustre_attr_default_easize.attr,
        &lustre_attr_xattr_cache.attr,
-       &lustre_attr_root_squash.attr,
        NULL,
 };