[PATCH] autofs4: add a show mount options for proc filesystem

Add show_options method to display autofs4 mount options in the proc
filesystem.

Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 34 insertions, 6 deletions

diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h
index 00da71d0f32a..d82a019ff8ef 100644
--- a/fs/autofs4/autofs_i.h
+++ b/fs/autofs4/autofs_i.h
@@ -87,11 +87,14 @@ struct autofs_wait_queue {
 struct autofs_sb_info {
         u32 magic;
         struct dentry *root;
+        int pipefd;
         struct file *pipe;
         pid_t oz_pgrp;
         int catatonic;
         int version;
         int sub_version;
+        int min_proto;
+        int max_proto;
         unsigned long exp_timeout;
         int reghost_enabled;
         int needs_reghost;
diff --git a/fs/autofs4/inode.c b/fs/autofs4/inode.c
index 2335b1d6490f..d9a71dab40fc 100644
--- a/fs/autofs4/inode.c
+++ b/fs/autofs4/inode.c
@@ -13,6 +13,7 @@
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/file.h>
+#include <linux/seq_file.h>
 #include <linux/pagemap.h>
 #include <linux/parser.h>
 #include <linux/bitops.h>
@@ -163,9 +164,26 @@ static void autofs4_put_super(struct super_block *sb)
         DPRINTK("shutting down");
 }
 
+static int autofs4_show_options(struct seq_file *m, struct vfsmount *mnt)
+{
+        struct autofs_sb_info *sbi = autofs4_sbi(mnt->mnt_sb);
+
+        if (!sbi)
+                return 0;
+
+        seq_printf(m, ",fd=%d", sbi->pipefd);
+        seq_printf(m, ",pgrp=%d", sbi->oz_pgrp);
+        seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ);
+        seq_printf(m, ",minproto=%d", sbi->min_proto);
+        seq_printf(m, ",maxproto=%d", sbi->max_proto);
+
+        return 0;
+}
+
 static struct super_operations autofs4_sops = {
         .put_super      = autofs4_put_super,
         .statfs         = simple_statfs,
+        .show_options   = autofs4_show_options,
 };
 
 enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto};
@@ -261,7 +279,6 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
         int pipefd;
         struct autofs_sb_info *sbi;
         struct autofs_info *ino;
-        int minproto, maxproto;
 
         sbi = (struct autofs_sb_info *) kmalloc(sizeof(*sbi), GFP_KERNEL);
         if ( !sbi )
@@ -273,12 +290,15 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
         s->s_fs_info = sbi;
         sbi->magic = AUTOFS_SBI_MAGIC;
         sbi->root = NULL;
+        sbi->pipefd = -1;
         sbi->catatonic = 0;
         sbi->exp_timeout = 0;
         sbi->oz_pgrp = process_group(current);
         sbi->sb = s;
         sbi->version = 0;
         sbi->sub_version = 0;
+        sbi->min_proto = 0;
+        sbi->max_proto = 0;
         mutex_init(&sbi->wq_mutex);
         spin_lock_init(&sbi->fs_lock);
         sbi->queues = NULL;
@@ -311,22 +331,26 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
         if (parse_options(data, &pipefd,
                           &root_inode->i_uid, &root_inode->i_gid,
                           &sbi->oz_pgrp,
-                          &minproto, &maxproto)) {
+                          &sbi->min_proto, &sbi->max_proto)) {
                 printk("autofs: called with bogus options\n");
                 goto fail_dput;
         }
 
         /* Couldn't this be tested earlier? */
-        if (maxproto < AUTOFS_MIN_PROTO_VERSION ||
-            minproto > AUTOFS_MAX_PROTO_VERSION) {
+        if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION ||
+            sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) {
                 printk("autofs: kernel does not match daemon version "
                        "daemon (%d, %d) kernel (%d, %d)\n",
-                        minproto, maxproto,
+                        sbi->min_proto, sbi->max_proto,
                         AUTOFS_MIN_PROTO_VERSION, AUTOFS_MAX_PROTO_VERSION);
                 goto fail_dput;
         }
 
-        sbi->version = maxproto > AUTOFS_MAX_PROTO_VERSION ? AUTOFS_MAX_PROTO_VERSION : maxproto;
+        /* Establish highest kernel protocol version */
+        if (sbi->max_proto > AUTOFS_MAX_PROTO_VERSION)
+                sbi->version = AUTOFS_MAX_PROTO_VERSION;
+        else
+                sbi->version = sbi->max_proto;
         sbi->sub_version = AUTOFS_PROTO_SUBVERSION;
 
         DPRINTK("pipe fd = %d, pgrp = %u", pipefd, sbi->oz_pgrp);
@@ -339,6 +363,7 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
         if ( !pipe->f_op || !pipe->f_op->write )
                 goto fail_fput;
         sbi->pipe = pipe;
+        sbi->pipefd = pipefd;
 
         /*
          * Take a reference to the root dentry so we get a chance to