[PATCH 10/75] Per-mount 'config' object

Alan Cox
2009-01-02T13:41:19Z

From: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>

With support for multiple mounts of devpts, the 'config' structure really
represents per-mount options rather than config parameters. Rename 'config'
structure to 'pts_mount_opts' and store it in the super-block.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Alan Cox <alan@redhat.com>
---

fs/devpts/inode.c | 45 +++++++++++++++++++++++++++------------------
1 files changed, 27 insertions(+), 18 deletions(-)

diff --git a/fs/devpts/inode.c b/fs/devpts/inode.c
index 49d879d..b793e6e 100644
--- a/fs/devpts/inode.c
+++ b/fs/devpts/inode.c
@@ -34,13 +34,13 @@ static DEFINE_MUTEX(allocated_ptys_lock);

static struct vfsmount *devpts_mnt;

-static struct {
+struct pts_mount_opts {
int setuid;
int setgid;
uid_t uid;
gid_t gid;
umode_t mode;
-} config = {.mode = DEVPTS_DEFAULT_MODE};
+};

enum {
Opt_uid, Opt_gid, Opt_mode,
@@ -56,6 +56,7 @@ static const match_table_t tokens = {

struct pts_fs_info {
struct ida allocated_ptys;
+ struct pts_mount_opts mount_opts;
};

static inline struct pts_fs_info *DEVPTS_SB(struct super_block *sb)
@@ -74,12 +75,14 @@ static inline struct super_block *pts_sb_from_inode(struct inode *inode)
static int devpts_remount(struct super_block *sb, int *flags, char *data)
{
char *p;
+ struct pts_fs_info *fsi = DEVPTS_SB(sb);
+ struct pts_mount_opts *opts = &fsi->mount_opts;

- config.setuid = 0;
- config.setgid = 0;
- config.uid = 0;
- config.gid = 0;
- config.mode = DEVPTS_DEFAULT_MODE;
+ opts->setuid = 0;
+ opts->setgid = 0;
+ opts->uid = 0;
+ opts->gid = 0;
+ opts->mode = DEVPTS_DEFAULT_MODE;

while ((p = strsep(&data, ",")) != NULL) {
substring_t args[MAX_OPT_ARGS];
@@ -94,19 +97,19 @@ static int devpts_remount(struct super_block *sb, int *flags, char *data)
case Opt_uid:
if (match_int(&args[0], &option))
return -EINVAL;
- config.uid = option;
- config.setuid = 1;
+ opts->uid = option;
+ opts->setuid = 1;
break;
case Opt_gid:
if (match_int(&args[0], &option))
return -EINVAL;
- config.gid = option;
- config.setgid = 1;
+ opts->gid = option;
+ opts->setgid = 1;
break;
case Opt_mode:
if (match_octal(&args[0], &option))
return -EINVAL;
- config.mode = option & S_IALLUGO;
+ opts->mode = option & S_IALLUGO;
break;
default:
printk(KERN_ERR "devpts: called with bogus options\n");
@@ -119,11 +122,14 @@ static int devpts_remount(struct super_block *sb, int *flags, char *data)

static int devpts_show_options(struct seq_file *seq, struct vfsmount *vfs)
{
- if (config.setuid)
- seq_printf(seq, ",uid=%u", config.uid);
- if (config.setgid)
- seq_printf(seq, ",gid=%u", config.gid);
- seq_printf(seq, ",mode=%03o", config.mode);
+ struct pts_fs_info *fsi = DEVPTS_SB(vfs->mnt_sb);
+ struct pts_mount_opts *opts = &fsi->mount_opts;
+
+ if (opts->setuid)
+ seq_printf(seq, ",uid=%u", opts->uid);
+ if (opts->setgid)
+ seq_printf(seq, ",gid=%u", opts->gid);
+ seq_printf(seq, ",mode=%03o", opts->mode);

return 0;
}
@@ -143,6 +149,7 @@ static void *new_pts_fs_info(void)
return NULL;

ida_init(&fsi->allocated_ptys);
+ fsi->mount_opts.mode = DEVPTS_DEFAULT_MODE;

return fsi;
}
@@ -262,6 +269,8 @@ int devpts_pty_new(struct inode *ptmx_inode, struct tty_struct *tty)
struct super_block *sb = pts_sb_from_inode(ptmx_inode);
struct inode *inode = new_inode(sb);
struct dentry *root = sb->s_root;
+ struct pts_fs_info *fsi = DEVPTS_SB(sb);
+ struct pts_mount_opts *opts = &fsi->mount_opts;
char s[12];

/* We're supposed to be given the slave end of a pty */
@@ -275,7 +284,7 @@ int devpts_pty_new(struct inode *ptmx_inode, struct tty_struct *tty)
inode->i_uid = config.setuid ? config.uid : current_fsuid();
inode->i_gid = config.setgid ? config.gid : current_fsgid();
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
- init_special_inode(inode, S_IFCHR|config.mode, device);
+ init_special_inode(inode, S_IFCHR|opts->mode, device);
inode->i_private = tty;
tty->driver_data = inode;