Parse mount options just once and copy them to super block

[linux-2.6-omap-h63xx.git] / fs / devpts / inode.c

diff --git a/fs/devpts/inode.c b/fs/devpts/inode.c
index fb4da9d8913078a24a2c8f7c3886aca841a25fd3..70013dd8ec7001db49bb52fb7a1516e38d672db0 100644 (file)
--- a/fs/devpts/inode.c
+++ b/fs/devpts/inode.c
@@ -321,61 +321,22 @@ static int compare_init_pts_sb(struct super_block *s, void *p)
        return 0;
 }
 
-/*
- * Safely parse the mount options in @data and update @opts.
- *
- * devpts ends up parsing options two times during mount, due to the
- * two modes of operation it supports. The first parse occurs in
- * devpts_get_sb() when determining the mode (single-instance or
- * multi-instance mode). The second parse happens in devpts_remount()
- * or new_pts_mount() depending on the mode.
- *
- * Parsing of options modifies the @data making subsequent parsing
- * incorrect. So make a local copy of @data and parse it.
- *
- * Return: 0 On success, -errno on error
- */
-static int safe_parse_mount_options(void *data, struct pts_mount_opts *opts)
-{
-       int rc;
-       void *datacp;
-
-       if (!data)
-               return 0;
-
-       /* Use kstrdup() ?  */
-       datacp = kmalloc(PAGE_SIZE, GFP_KERNEL);
-       if (!datacp)
-               return -ENOMEM;
-
-       memcpy(datacp, data, PAGE_SIZE);
-       rc = parse_mount_options((char *)datacp, PARSE_MOUNT, opts);
-       kfree(datacp);
-
-       return rc;
-}
-
 /*
  * Mount a new (private) instance of devpts.  PTYs created in this
  * instance are independent of the PTYs in other devpts instances.
  */
 static int new_pts_mount(struct file_system_type *fs_type, int flags,
-               void *data, struct vfsmount *mnt)
+               void *data, struct pts_mount_opts *opts, struct vfsmount *mnt)
 {
        int err;
        struct pts_fs_info *fsi;
-       struct pts_mount_opts *opts;
 
        err = get_sb_nodev(fs_type, flags, data, devpts_fill_super, mnt);
        if (err)
                return err;
 
        fsi = DEVPTS_SB(mnt->mnt_sb);
-       opts = &fsi->mount_opts;
-
-       err = parse_mount_options(data, PARSE_MOUNT, opts);
-       if (err)
-               goto fail;
+       memcpy(&fsi->mount_opts, opts, sizeof(opts));
 
        err = mknod_ptmx(mnt->mnt_sb);
        if (err)
@@ -390,28 +351,6 @@ fail:
        return err;
 }
 
-/*
- * Check if 'newinstance' mount option was specified in @data.
- *
- * Return: -errno      on error (eg: invalid mount options specified)
- *      : 1            if 'newinstance' mount option was specified
- *      : 0            if 'newinstance' mount option was NOT specified
- */
-static int is_new_instance_mount(void *data)
-{
-       int rc;
-       struct pts_mount_opts opts;
-
-       if (!data)
-               return 0;
-
-       rc = safe_parse_mount_options(data, &opts);
-       if (!rc)
-               rc = opts.newinstance;
-
-       return rc;
-}
-
 /*
  * get_init_pts_sb()
  *
@@ -434,10 +373,9 @@ static int is_new_instance_mount(void *data)
  *     presence of the private namespace (i.e 'newinstance') super-blocks.
  */
 static int get_init_pts_sb(struct file_system_type *fs_type, int flags,
-               void *data, struct vfsmount *mnt)
+               void *data, struct pts_mount_opts *opts, struct vfsmount *mnt)
 {
        struct super_block *s;
-       struct pts_mount_opts *opts;
        struct pts_fs_info *fsi;
        int error;
 
@@ -455,11 +393,12 @@ static int get_init_pts_sb(struct file_system_type *fs_type, int flags,
                }
                s->s_flags |= MS_ACTIVE;
        }
-       fsi = DEVPTS_SB(s);
-       opts = &fsi->mount_opts;
-       parse_mount_options(data, PARSE_REMOUNT, opts);
 
        simple_set_mnt(mnt, s);
+
+       fsi = DEVPTS_SB(mnt->mnt_sb);
+       memcpy(&fsi->mount_opts, opts, sizeof(opts));
+
        return 0;
 }
 
@@ -469,11 +408,11 @@ static int get_init_pts_sb(struct file_system_type *fs_type, int flags,
  * kernel still allows multiple-instances.
  */
 static int init_pts_mount(struct file_system_type *fs_type, int flags,
-               void *data, struct vfsmount *mnt)
+               void *data, struct pts_mount_opts *opts, struct vfsmount *mnt)
 {
        int err;
 
-       err = get_init_pts_sb(fs_type, flags, data, mnt);
+       err = get_init_pts_sb(fs_type, flags, data, opts, mnt);
        if (err)
                return err;
 
@@ -490,17 +429,22 @@ static int init_pts_mount(struct file_system_type *fs_type, int flags,
 static int devpts_get_sb(struct file_system_type *fs_type,
        int flags, const char *dev_name, void *data, struct vfsmount *mnt)
 {
-       int new;
-
-       new = is_new_instance_mount(data);
-       if (new < 0)
-               return new;
+       int error;
+       struct pts_mount_opts opts;
 
-       if (new)
-               return new_pts_mount(fs_type, flags, data, mnt);
+       memset(&opts, 0, sizeof(opts));
+       if (data) {
+               error = parse_mount_options(data, PARSE_MOUNT, &opts);
+               if (error)
+                       return error;
+       }
 
-       return init_pts_mount(fs_type, flags, data, mnt);
+       if (opts.newinstance)
+               return new_pts_mount(fs_type, flags, data, &opts, mnt);
+       else
+               return init_pts_mount(fs_type, flags, data, &opts, mnt);
 }
+
 #else
 /*
  * This supports only the legacy single-instance semantics (no