2 files changed, 100 insertions, 29 deletions

diff --git a/fs/autofs4/dev-ioctl.c b/fs/autofs4/dev-ioctl.c
index 63b7c7afe8df..054d6d9ad9ba 100644
--- a/fs/autofs4/dev-ioctl.c
+++ b/fs/autofs4/dev-ioctl.c
@@ -180,7 +180,7 @@ static int autofs_dev_ioctl_protover(struct file *fp,
                                      struct autofs_sb_info *sbi,
                                      struct autofs_dev_ioctl *param)
 {
-        param->arg1 = sbi->version;
+        param->protover.version = sbi->version;
         return 0;
 }
 
@@ -189,7 +189,7 @@ static int autofs_dev_ioctl_protosubver(struct file *fp,
                                         struct autofs_sb_info *sbi,
                                         struct autofs_dev_ioctl *param)
 {
-        param->arg1 = sbi->sub_version;
+        param->protosubver.sub_version = sbi->sub_version;
         return 0;
 }
 
@@ -335,13 +335,13 @@ static int autofs_dev_ioctl_openmount(struct file *fp,
         int err, fd;
 
         /* param->path has already been checked */
-        if (!param->arg1)
+        if (!param->openmount.devid)
                 return -EINVAL;
 
         param->ioctlfd = -1;
 
         path = param->path;
-        devid = param->arg1;
+        devid = param->openmount.devid;
 
         err = 0;
         fd = autofs_dev_ioctl_open_mountpoint(path, devid);
@@ -373,7 +373,7 @@ static int autofs_dev_ioctl_ready(struct file *fp,
 {
         autofs_wqt_t token;
 
-        token = (autofs_wqt_t) param->arg1;
+        token = (autofs_wqt_t) param->ready.token;
         return autofs4_wait_release(sbi, token, 0);
 }
 
@@ -388,8 +388,8 @@ static int autofs_dev_ioctl_fail(struct file *fp,
         autofs_wqt_t token;
         int status;
 
-        token = (autofs_wqt_t) param->arg1;
-        status = param->arg2 ? param->arg2 : -ENOENT;
+        token = (autofs_wqt_t) param->fail.token;
+        status = param->fail.status ? param->fail.status : -ENOENT;
         return autofs4_wait_release(sbi, token, status);
 }
 
@@ -412,10 +412,10 @@ static int autofs_dev_ioctl_setpipefd(struct file *fp,
         int pipefd;
         int err = 0;
 
-        if (param->arg1 == -1)
+        if (param->setpipefd.pipefd == -1)
                 return -EINVAL;
 
-        pipefd = param->arg1;
+        pipefd = param->setpipefd.pipefd;
 
         mutex_lock(&sbi->wq_mutex);
         if (!sbi->catatonic) {
@@ -457,8 +457,8 @@ static int autofs_dev_ioctl_timeout(struct file *fp,
 {
         unsigned long timeout;
 
-        timeout = param->arg1;
-        param->arg1 = sbi->exp_timeout / HZ;
+        timeout = param->timeout.timeout;
+        param->timeout.timeout = sbi->exp_timeout / HZ;
         sbi->exp_timeout = timeout * HZ;
         return 0;
 }
@@ -489,7 +489,7 @@ static int autofs_dev_ioctl_requester(struct file *fp,
         path = param->path;
         devid = sbi->sb->s_dev;
 
-        param->arg1 = param->arg2 = -1;
+        param->requester.uid = param->requester.gid = -1;
 
         /* Get nameidata of the parent directory */
         err = path_lookup(path, LOOKUP_PARENT, &nd);
@@ -505,8 +505,8 @@ static int autofs_dev_ioctl_requester(struct file *fp,
                 err = 0;
                 autofs4_expire_wait(nd.path.dentry);
                 spin_lock(&sbi->fs_lock);
-                param->arg1 = ino->uid;
-                param->arg2 = ino->gid;
+                param->requester.uid = ino->uid;
+                param->requester.gid = ino->gid;
                 spin_unlock(&sbi->fs_lock);
         }
 
@@ -529,7 +529,7 @@ static int autofs_dev_ioctl_expire(struct file *fp,
         int err = -EAGAIN;
         int how;
 
-        how = param->arg1;
+        how = param->expire.how;
         mnt = fp->f_path.mnt;
 
         if (sbi->type & AUTOFS_TYPE_TRIGGER)
@@ -565,9 +565,9 @@ static int autofs_dev_ioctl_askumount(struct file *fp,
                                       struct autofs_sb_info *sbi,
                                       struct autofs_dev_ioctl *param)
 {
-        param->arg1 = 0;
+        param->askumount.may_umount = 0;
         if (may_umount(fp->f_path.mnt))
-                param->arg1 = 1;
+                param->askumount.may_umount = 1;
         return 0;
 }
 
@@ -600,6 +600,7 @@ static int autofs_dev_ioctl_ismountpoint(struct file *fp,
         struct nameidata nd;
         const char *path;
         unsigned int type;
+        unsigned int devid, magic;
         int err = -ENOENT;
 
         if (param->size <= sizeof(*param)) {
@@ -608,10 +609,10 @@ static int autofs_dev_ioctl_ismountpoint(struct file *fp,
         }
 
         path = param->path;
-        type = param->arg1;
+        type = param->ismountpoint.in.type;
 
-        param->arg1 = 0;
-        param->arg2 = 0;
+        param->ismountpoint.out.devid = devid = 0;
+        param->ismountpoint.out.magic = magic = 0;
 
         if (!fp || param->ioctlfd == -1) {
                 if (type == AUTOFS_TYPE_ANY) {
@@ -622,7 +623,7 @@ static int autofs_dev_ioctl_ismountpoint(struct file *fp,
                                 goto out;
 
                         sb = nd.path.dentry->d_sb;
-                        param->arg1 = new_encode_dev(sb->s_dev);
+                        devid = new_encode_dev(sb->s_dev);
                 } else {
                         struct autofs_info *ino;
 
@@ -635,14 +636,14 @@ static int autofs_dev_ioctl_ismountpoint(struct file *fp,
                                 goto out_release;
 
                         ino = autofs4_dentry_ino(nd.path.dentry);
-                        param->arg1 = autofs4_get_dev(ino->sbi);
+                        devid = autofs4_get_dev(ino->sbi);
                 }
 
                 err = 0;
                 if (nd.path.dentry->d_inode &&
                     nd.path.mnt->mnt_root == nd.path.dentry) {
                         err = 1;
-                        param->arg2 = nd.path.dentry->d_inode->i_sb->s_magic;
+                        magic = nd.path.dentry->d_inode->i_sb->s_magic;
                 }
         } else {
                 dev_t devid = new_encode_dev(sbi->sb->s_dev);
@@ -655,18 +656,21 @@ static int autofs_dev_ioctl_ismountpoint(struct file *fp,
                 if (err)
                         goto out_release;
 
-                param->arg1 = autofs4_get_dev(sbi);
+                devid = autofs4_get_dev(sbi);
 
                 err = have_submounts(nd.path.dentry);
 
                 if (nd.path.mnt->mnt_mountpoint != nd.path.mnt->mnt_root) {
                         if (follow_down(&nd.path.mnt, &nd.path.dentry)) {
                                 struct inode *inode = nd.path.dentry->d_inode;
-                                param->arg2 = inode->i_sb->s_magic;
+                                magic = inode->i_sb->s_magic;
                         }
                 }
         }
 
+        param->ismountpoint.out.devid = devid;
+        param->ismountpoint.out.magic = magic;
+
 out_release:
         path_put(&nd.path);
 out:
diff --git a/include/linux/auto_dev-ioctl.h b/include/linux/auto_dev-ioctl.h
index f4d05ccd731f..91a773993a5c 100644
--- a/include/linux/auto_dev-ioctl.h
+++ b/include/linux/auto_dev-ioctl.h
@@ -10,6 +10,7 @@
 #ifndef _LINUX_AUTO_DEV_IOCTL_H
 #define _LINUX_AUTO_DEV_IOCTL_H
 
+#include <linux/string.h>
 #include <linux/types.h>
 
 #define AUTOFS_DEVICE_NAME              "autofs"
@@ -25,6 +26,60 @@
  * An ioctl interface for autofs mount point control.
  */
 
+struct args_protover {
+        __u32   version;
+};
+
+struct args_protosubver {
+        __u32   sub_version;
+};
+
+struct args_openmount {
+        __u32   devid;
+};
+
+struct args_ready {
+        __u32   token;
+};
+
+struct args_fail {
+        __u32   token;
+        __s32   status;
+};
+
+struct args_setpipefd {
+        __s32   pipefd;
+};
+
+struct args_timeout {
+        __u64   timeout;
+};
+
+struct args_requester {
+        __u32   uid;
+        __u32   gid;
+};
+
+struct args_expire {
+        __u32   how;
+};
+
+struct args_askumount {
+        __u32   may_umount;
+};
+
+struct args_ismountpoint {
+        union {
+                struct args_in {
+                        __u32   type;
+                } in;
+                struct args_out {
+                        __u32   devid;
+                        __u32   magic;
+                } out;
+        };
+};
+
 /*
  * All the ioctls use this structure.
  * When sending a path size must account for the total length
@@ -39,20 +94,32 @@ struct autofs_dev_ioctl {
                                  * including this struct */
         __s32 ioctlfd;          /* automount command fd */
 
-        __u32 arg1;             /* Command parameters */
-        __u32 arg2;
+        /* Command parameters */
+
+        union {
+                struct args_protover            protover;
+                struct args_protosubver         protosubver;
+                struct args_openmount           openmount;
+                struct args_ready               ready;
+                struct args_fail                fail;
+                struct args_setpipefd           setpipefd;
+                struct args_timeout             timeout;
+                struct args_requester           requester;
+                struct args_expire              expire;
+                struct args_askumount           askumount;
+                struct args_ismountpoint        ismountpoint;
+        };
 
         char path[0];
 };
 
 static inline void init_autofs_dev_ioctl(struct autofs_dev_ioctl *in)
 {
+        memset(in, 0, sizeof(struct autofs_dev_ioctl));
         in->ver_major = AUTOFS_DEV_IOCTL_VERSION_MAJOR;
         in->ver_minor = AUTOFS_DEV_IOCTL_VERSION_MINOR;
         in->size = sizeof(struct autofs_dev_ioctl);
         in->ioctlfd = -1;
-        in->arg1 = 0;
-        in->arg2 = 0;
         return;
 }