[PATCH 11/14] isofs: Implement show_options

From: David Howells
Date: Wed Jul 05 2017 - 11:25:43 EST


Implement the show_options superblock op for omfs as part of a bid to get
rid of s_options and generic_show_options() to make it easier to implement
a context-based mount where the mount options can be passed individually
over a file descriptor.

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
cc: Jan Kara <jack@xxxxxxx>
---

fs/isofs/inode.c | 51 ++++++++++++++++++++++++++++++++++++++++++++++++---
fs/isofs/isofs.h | 3 +++
2 files changed, 51 insertions(+), 3 deletions(-)

diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c
index 020ba0936146..f80ee600d1bc 100644
--- a/fs/isofs/inode.c
+++ b/fs/isofs/inode.c
@@ -23,6 +23,7 @@
#include <linux/parser.h>
#include <linux/mpage.h>
#include <linux/user_namespace.h>
+#include <linux/seq_file.h>

#include "isofs.h"
#include "zisofs.h"
@@ -57,6 +58,7 @@ static void isofs_put_super(struct super_block *sb)

static int isofs_read_inode(struct inode *, int relocated);
static int isofs_statfs (struct dentry *, struct kstatfs *);
+static int isofs_show_options(struct seq_file *, struct dentry *);

static struct kmem_cache *isofs_inode_cachep;

@@ -123,7 +125,7 @@ static const struct super_operations isofs_sops = {
.put_super = isofs_put_super,
.statfs = isofs_statfs,
.remount_fs = isofs_remount,
- .show_options = generic_show_options,
+ .show_options = isofs_show_options,
};


@@ -473,6 +475,48 @@ static int parse_options(char *options, struct iso9660_options *popt)
}

/*
+ * Display the mount options in /proc/mounts.
+ */
+static int isofs_show_options(struct seq_file *m, struct dentry *root)
+{
+ struct isofs_sb_info *sbi = ISOFS_SB(root->d_sb);
+
+ if (!sbi->s_rock) seq_puts(m, ",norock");
+ else if (!sbi->s_joliet_level) seq_puts(m, ",nojoliet");
+ if (sbi->s_cruft) seq_puts(m, ",cruft");
+ if (sbi->s_hide) seq_puts(m, ",hide");
+ if (sbi->s_nocompress) seq_puts(m, ",nocompress");
+ if (sbi->s_overriderockperm) seq_puts(m, ",overriderockperm");
+ if (sbi->s_showassoc) seq_puts(m, ",showassoc");
+ if (sbi->s_utf8) seq_puts(m, ",utf8");
+
+ if (sbi->s_check) seq_printf(m, ",check=%c", sbi->s_check);
+ if (sbi->s_mapping) seq_printf(m, ",map=%c", sbi->s_mapping);
+ if (sbi->s_session != -1) seq_printf(m, ",session=%u", sbi->s_session);
+ if (sbi->s_sbsector != -1) seq_printf(m, ",sbsector=%u", sbi->s_sbsector);
+
+ if (root->d_sb->s_blocksize != 1024)
+ seq_printf(m, ",blocksize=%lu", root->d_sb->s_blocksize);
+
+ if (sbi->s_uid_set)
+ seq_printf(m, ",uid=%u",
+ from_kuid_munged(&init_user_ns, sbi->s_uid));
+ if (sbi->s_gid_set)
+ seq_printf(m, ",gid=%u",
+ from_kgid_munged(&init_user_ns, sbi->s_gid));
+
+ if (sbi->s_dmode != ISOFS_INVALID_MODE)
+ seq_printf(m, ",dmode=%o", sbi->s_dmode);
+ if (sbi->s_fmode != ISOFS_INVALID_MODE)
+ seq_printf(m, ",fmode=%o", sbi->s_fmode);
+
+ if (sbi->s_nls_iocharset &&
+ strcmp(sbi->s_nls_iocharset->charset, CONFIG_NLS_DEFAULT) != 0)
+ seq_printf(m, ",iocharset=%s", sbi->s_nls_iocharset->charset);
+ return 0;
+}
+
+/*
* look if the driver can tell the multi session redirection value
*
* don't change this if you don't know what you do, please!
@@ -583,8 +627,6 @@ static int isofs_fill_super(struct super_block *s, void *data, int silent)
int table, error = -EINVAL;
unsigned int vol_desc_start;

- save_mount_options(s, data);
-
sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
if (!sbi)
return -ENOMEM;
@@ -605,6 +647,8 @@ static int isofs_fill_super(struct super_block *s, void *data, int silent)
opt.blocksize = sb_min_blocksize(s, opt.blocksize);

sbi->s_high_sierra = 0; /* default is iso9660 */
+ sbi->s_session = opt.session;
+ sbi->s_sbsector = opt.sbsector;

vol_desc_start = (opt.sbsector != -1) ?
opt.sbsector : isofs_get_last_session(s,opt.session);
@@ -911,6 +955,7 @@ static int isofs_fill_super(struct super_block *s, void *data, int silent)
table += 2;
if (opt.check == 'r')
table++;
+ sbi->s_check = opt.check;

if (table)
s->s_d_op = &isofs_dentry_ops[table - 1];
diff --git a/fs/isofs/isofs.h b/fs/isofs/isofs.h
index 0ac4c1f73fbd..133a456b0425 100644
--- a/fs/isofs/isofs.h
+++ b/fs/isofs/isofs.h
@@ -36,8 +36,11 @@ struct isofs_sb_info {
unsigned long s_max_size;

int s_rock_offset; /* offset of SUSP fields within SU area */
+ s32 s_sbsector;
unsigned char s_joliet_level;
unsigned char s_mapping;
+ unsigned char s_check;
+ unsigned char s_session;
unsigned int s_high_sierra:1;
unsigned int s_rock:2;
unsigned int s_utf8:1;