From: Ian Kent <ra...@themaw.net>
The new fsinfo() system call adds a new super block operation
->fsinfo() which is used by file systems to provide file
system specific information for fsinfo() requests.
The fsinfo() request FSINFO_ATTR_PARAMETERS provides the same
function as sb operation ->show_options() so it needs to be
implemented by any file system that provides ->show_options()
as a minimum.
Signed-off-by: Ian Kent <ra...@themaw.net>
Signed-off-by: David Howells <dhowe...@redhat.com>
---
fs/ufs/super.c | 57 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 57 insertions(+)
diff --git a/fs/ufs/super.c b/fs/ufs/super.c
index 84c0c5178cd2..6395ce4da5e6 100644
--- a/fs/ufs/super.c
+++ b/fs/ufs/super.c
@@ -89,6 +89,7 @@
#include <linux/mount.h>
#include <linux/seq_file.h>
#include <linux/iversion.h>
+#include <linux/fsinfo.h>
#include "ufs_fs.h"
#include "ufs.h"
@@ -1401,6 +1402,59 @@ static int ufs_show_options(struct seq_file *seq, struct
dentry *root)
return 0;
}
+#ifdef CONFIG_FSINFO
+static int ufs_fsinfo_print_token(struct fsinfo_kparams *params, const char
*token)
+{
+ char *new, *key, *value;
+
+ new = kstrdup(token, GFP_KERNEL);
+ if (!new)
+ return -ENOMEM;
+
+ key = new;
+ value = strchr(new, '=');
+ if (value)
+ *value++ = '\0';
+
+ fsinfo_note_param(params, key, value);
+
+ kfree(new);
+ return 0;
+}
+
+/*
+ * Get filesystem information.
+ */
+static int ufs_fsinfo(struct path *path, struct fsinfo_kparams *params)
+{
+ struct ufs_sb_info *sbi = UFS_SB(path->dentry->d_sb);
+ unsigned mval = sbi->s_mount_opt & UFS_MOUNT_UFSTYPE;
+ const struct match_token *tp = tokens;
+ int ret;
+
+ switch (params->request) {
+ case FSINFO_ATTR_PARAMETERS:
+ while (tp->token != Opt_onerror_panic && tp->token != mval)
+ ++tp;
+ BUG_ON(tp->token == Opt_onerror_panic);
+ ret = ufs_fsinfo_print_token(params, tp->pattern);
+ if (ret)
+ return ret;
+ mval = sbi->s_mount_opt & UFS_MOUNT_ONERROR;
+ while (tp->token != Opt_err && tp->token != mval)
+ ++tp;
+ BUG_ON(tp->token == Opt_err);
+ ret = ufs_fsinfo_print_token(params, tp->pattern);
+ if (ret)
+ return ret;
+ return params->usage;
+
+ default:
+ return generic_fsinfo(path, params);
+ }
+}
+#endif /* CONFIG_FSINFO */
+
static int ufs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
struct super_block *sb = dentry->d_sb;
@@ -1496,6 +1550,9 @@ static const struct super_operations ufs_super_ops = {
.statfs = ufs_statfs,
.remount_fs = ufs_remount,
.show_options = ufs_show_options,
+#ifdef CONFIG_FSINFO
+ .fsinfo = ufs_fsinfo,
+#endif
};
static struct dentry *ufs_mount(struct file_system_type *fs_type,
