filesystem freeze: allow SysRq emergency thaw to thaw frozen filesystems

[safe/jmp/linux-2.6] / fs / ocfs2 / ioctl.c

diff --git a/fs/ocfs2/ioctl.c b/fs/ocfs2/ioctl.c
index 7003d58..9fcd36d 100644 (file)
--- a/fs/ocfs2/ioctl.c
+++ b/fs/ocfs2/ioctl.c
@@ -7,6 +7,7 @@
 
 #include <linux/fs.h>
 #include <linux/mount.h>
+#include <linux/smp_lock.h>
 
 #define MLOG_MASK_PREFIX ML_INODE
 #include <cluster/masklog.h>
@@ -59,10 +60,6 @@ static int ocfs2_set_inode_attr(struct inode *inode, unsigned flags,
                goto bail;
        }
 
-       status = -EROFS;
-       if (IS_RDONLY(inode))
-               goto bail_unlock;
-
        status = -EACCES;
        if (!is_owner_or_cap(inode))
                goto bail_unlock;
@@ -105,16 +102,15 @@ bail_unlock:
 bail:
        mutex_unlock(&inode->i_mutex);
 
-       if (bh)
-               brelse(bh);
+       brelse(bh);
 
        mlog_exit(status);
        return status;
 }
 
-int ocfs2_ioctl(struct inode * inode, struct file * filp,
-       unsigned int cmd, unsigned long arg)
+long ocfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 {
+       struct inode *inode = filp->f_path.dentry->d_inode;
        unsigned int flags;
        int new_clusters;
        int status;
@@ -133,8 +129,13 @@ int ocfs2_ioctl(struct inode * inode, struct file * filp,
                if (get_user(flags, (int __user *) arg))
                        return -EFAULT;
 
-               return ocfs2_set_inode_attr(inode, flags,
+               status = mnt_want_write(filp->f_path.mnt);
+               if (status)
+                       return status;
+               status = ocfs2_set_inode_attr(inode, flags,
                        OCFS2_FL_MODIFIABLE);
+               mnt_drop_write(filp->f_path.mnt);
+               return status;
        case OCFS2_IOC_RESVSP:
        case OCFS2_IOC_RESVSP64:
        case OCFS2_IOC_UNRESVSP:
@@ -144,12 +145,18 @@ int ocfs2_ioctl(struct inode * inode, struct file * filp,
 
                return ocfs2_change_file_space(filp, cmd, &sr);
        case OCFS2_IOC_GROUP_EXTEND:
+               if (!capable(CAP_SYS_RESOURCE))
+                       return -EPERM;
+
                if (get_user(new_clusters, (int __user *)arg))
                        return -EFAULT;
 
                return ocfs2_group_extend(inode, new_clusters);
        case OCFS2_IOC_GROUP_ADD:
        case OCFS2_IOC_GROUP_ADD64:
+               if (!capable(CAP_SYS_RESOURCE))
+                       return -EPERM;
+
                if (copy_from_user(&input, (int __user *) arg, sizeof(input)))
                        return -EFAULT;
 
@@ -162,9 +169,6 @@ int ocfs2_ioctl(struct inode * inode, struct file * filp,
 #ifdef CONFIG_COMPAT
 long ocfs2_compat_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 {
-       struct inode *inode = file->f_path.dentry->d_inode;
-       int ret;
-
        switch (cmd) {
        case OCFS2_IOC32_GETFLAGS:
                cmd = OCFS2_IOC_GETFLAGS;
@@ -184,9 +188,6 @@ long ocfs2_compat_ioctl(struct file *file, unsigned cmd, unsigned long arg)
                return -ENOIOCTLCMD;
        }
 
-       lock_kernel();
-       ret = ocfs2_ioctl(inode, file, cmd, arg);
-       unlock_kernel();
-       return ret;
+       return ocfs2_ioctl(file, cmd, arg);
 }
 #endif