xfs: remove old vmap cache
[linux-2.6.git] / fs / super.c
index d28fde7..f35ac60 100644 (file)
@@ -15,7 +15,7 @@
  *  Added kerneld support: Jacques Gelinas and Bjorn Ekwall
  *  Added change_root: Werner Almesberger & Hans Lermen, Feb '96
  *  Added options to /proc/mounts:
- *    Torbjörn Lindh (torbjorn.lindh@gopta.se), April 14, 1996.
+ *    Torbjörn Lindh (torbjorn.lindh@gopta.se), April 14, 1996.
  *  Added devfs support: Richard Gooch <rgooch@atnf.csiro.au>, 13-JAN-1998
  *  Heavily rewritten for 'one fs - one tree' dcache architecture. AV, Mar 2000
  */
@@ -28,7 +28,6 @@
 #include <linux/blkdev.h>
 #include <linux/quotaops.h>
 #include <linux/namei.h>
-#include <linux/buffer_head.h>         /* for fsync_super() */
 #include <linux/mount.h>
 #include <linux/security.h>
 #include <linux/syscalls.h>
@@ -37,7 +36,9 @@
 #include <linux/idr.h>
 #include <linux/kobject.h>
 #include <linux/mutex.h>
+#include <linux/file.h>
 #include <asm/uaccess.h>
+#include "internal.h"
 
 
 LIST_HEAD(super_blocks);
@@ -53,7 +54,7 @@ DEFINE_SPINLOCK(sb_lock);
 static struct super_block *alloc_super(struct file_system_type *type)
 {
        struct super_block *s = kzalloc(sizeof(struct super_block),  GFP_USER);
-       static struct super_operations default_op;
+       static const struct super_operations default_op;
 
        if (s) {
                if (security_sb_alloc(s)) {
@@ -61,13 +62,11 @@ static struct super_block *alloc_super(struct file_system_type *type)
                        s = NULL;
                        goto out;
                }
-               INIT_LIST_HEAD(&s->s_dirty);
-               INIT_LIST_HEAD(&s->s_io);
-               INIT_LIST_HEAD(&s->s_more_io);
                INIT_LIST_HEAD(&s->s_files);
                INIT_LIST_HEAD(&s->s_instances);
                INIT_HLIST_HEAD(&s->s_anon);
                INIT_LIST_HEAD(&s->s_inodes);
+               INIT_LIST_HEAD(&s->s_dentry_lru);
                init_rwsem(&s->s_umount);
                mutex_init(&s->s_lock);
                lockdep_set_class(&s->s_umount, &type->s_umount_key);
@@ -77,7 +76,22 @@ static struct super_block *alloc_super(struct file_system_type *type)
                 * lock ordering than usbfs:
                 */
                lockdep_set_class(&s->s_lock, &type->s_lock_key);
-               down_write(&s->s_umount);
+               /*
+                * sget() can have s_umount recursion.
+                *
+                * When it cannot find a suitable sb, it allocates a new
+                * one (this one), and tries again to find a suitable old
+                * one.
+                *
+                * In case that succeeds, it will acquire the s_umount
+                * lock of the old one. Since these are clearly distrinct
+                * locks, and this object isn't exposed yet, there's no
+                * risk of deadlocks.
+                *
+                * Annotate this by putting this lock in a different
+                * subclass.
+                */
+               down_write_nested(&s->s_umount, SINGLE_DEPTH_NESTING);
                s->s_count = S_BIAS;
                atomic_set(&s->s_active, 1);
                mutex_init(&s->s_vfs_rename_mutex);
@@ -105,6 +119,7 @@ static inline void destroy_super(struct super_block *s)
 {
        security_sb_free(s);
        kfree(s->s_subtype);
+       kfree(s->s_options);
        kfree(s);
 }
 
@@ -114,7 +129,7 @@ static inline void destroy_super(struct super_block *s)
  * Drop a superblock's refcount.  Returns non-zero if the superblock was
  * destroyed.  The caller must hold sb_lock.
  */
-int __put_super(struct super_block *sb)
+static int __put_super(struct super_block *sb)
 {
        int ret = 0;
 
@@ -153,7 +168,7 @@ int __put_super_and_need_restart(struct super_block *sb)
  *     Drops a temporary reference, frees superblock if there's no
  *     references left.
  */
-static void put_super(struct super_block *sb)
+void put_super(struct super_block *sb)
 {
        spin_lock(&sb_lock);
        __put_super(sb);
@@ -176,7 +191,7 @@ void deactivate_super(struct super_block *s)
        if (atomic_dec_and_lock(&s->s_active, &sb_lock)) {
                s->s_count -= S_BIAS-1;
                spin_unlock(&sb_lock);
-               DQUOT_OFF(s);
+               vfs_dq_off(s, 0);
                down_write(&s->s_umount);
                fs->kill_sb(s);
                put_filesystem(fs);
@@ -187,6 +202,34 @@ void deactivate_super(struct super_block *s)
 EXPORT_SYMBOL(deactivate_super);
 
 /**
+ *     deactivate_locked_super -       drop an active reference to superblock
+ *     @s: superblock to deactivate
+ *
+ *     Equivalent of up_write(&s->s_umount); deactivate_super(s);, except that
+ *     it does not unlock it until it's all over.  As the result, it's safe to
+ *     use to dispose of new superblock on ->get_sb() failure exits - nobody
+ *     will see the sucker until it's all over.  Equivalent using up_write +
+ *     deactivate_super is safe for that purpose only if superblock is either
+ *     safe to use or has NULL ->s_root when we unlock.
+ */
+void deactivate_locked_super(struct super_block *s)
+{
+       struct file_system_type *fs = s->s_type;
+       if (atomic_dec_and_lock(&s->s_active, &sb_lock)) {
+               s->s_count -= S_BIAS-1;
+               spin_unlock(&sb_lock);
+               vfs_dq_off(s, 0);
+               fs->kill_sb(s);
+               put_filesystem(fs);
+               put_super(s);
+       } else {
+               up_write(&s->s_umount);
+       }
+}
+
+EXPORT_SYMBOL(deactivate_locked_super);
+
+/**
  *     grab_super - acquire an active reference
  *     @s: reference we are trying to make active
  *
@@ -236,37 +279,6 @@ void unlock_super(struct super_block * sb)
 EXPORT_SYMBOL(lock_super);
 EXPORT_SYMBOL(unlock_super);
 
-/*
- * Write out and wait upon all dirty data associated with this
- * superblock.  Filesystem data as well as the underlying block
- * device.  Takes the superblock lock.  Requires a second blkdev
- * flush by the caller to complete the operation.
- */
-void __fsync_super(struct super_block *sb)
-{
-       sync_inodes_sb(sb, 0);
-       DQUOT_SYNC(sb);
-       lock_super(sb);
-       if (sb->s_dirt && sb->s_op->write_super)
-               sb->s_op->write_super(sb);
-       unlock_super(sb);
-       if (sb->s_op->sync_fs)
-               sb->s_op->sync_fs(sb, 1);
-       sync_blockdev(sb->s_bdev);
-       sync_inodes_sb(sb, 1);
-}
-
-/*
- * Write out and wait upon all dirty data associated with this
- * superblock.  Filesystem data as well as the underlying block
- * device.  Takes the superblock lock.
- */
-int fsync_super(struct super_block *sb)
-{
-       __fsync_super(sb);
-       return sync_blockdev(sb->s_bdev);
-}
-
 /**
  *     generic_shutdown_super  -       common helper for ->kill_sb()
  *     @sb: superblock to kill
@@ -285,17 +297,16 @@ void generic_shutdown_super(struct super_block *sb)
 {
        const struct super_operations *sop = sb->s_op;
 
+
        if (sb->s_root) {
                shrink_dcache_for_umount(sb);
-               fsync_super(sb);
-               lock_super(sb);
+               sync_filesystem(sb);
+               get_fs_excl();
                sb->s_flags &= ~MS_ACTIVE;
+
                /* bad name - it should be evict_inodes() */
                invalidate_inodes(sb);
-               lock_kernel();
 
-               if (sop->write_super && sb->s_dirt)
-                       sop->write_super(sb);
                if (sop->put_super)
                        sop->put_super(sb);
 
@@ -305,9 +316,7 @@ void generic_shutdown_super(struct super_block *sb)
                           "Self-destruct in 5 seconds.  Have a nice day...\n",
                           sb->s_id);
                }
-
-               unlock_kernel();
-               unlock_super(sb);
+               put_fs_excl();
        }
        spin_lock(&sb_lock);
        /* should be initialized for __put_super_and_need_restart() */
@@ -343,8 +352,10 @@ retry:
                                continue;
                        if (!grab_super(old))
                                goto retry;
-                       if (s)
+                       if (s) {
+                               up_write(&s->s_umount);
                                destroy_super(s);
+                       }
                        return old;
                }
        }
@@ -359,6 +370,7 @@ retry:
        err = set(s, data);
        if (err) {
                spin_unlock(&sb_lock);
+               up_write(&s->s_umount);
                destroy_super(s);
                return ERR_PTR(err);
        }
@@ -381,16 +393,14 @@ void drop_super(struct super_block *sb)
 
 EXPORT_SYMBOL(drop_super);
 
-static inline void write_super(struct super_block *sb)
-{
-       lock_super(sb);
-       if (sb->s_root && sb->s_dirt)
-               if (sb->s_op->write_super)
-                       sb->s_op->write_super(sb);
-       unlock_super(sb);
-}
-
-/*
+/**
+ * sync_supers - helper for periodic superblock writeback
+ *
+ * Call the write_super method if present on all dirty superblocks in
+ * the system.  This is for the periodic writeback used by most older
+ * filesystems.  For data integrity superblock writeback use
+ * sync_filesystems() instead.
+ *
  * Note: check the dirty flag before waiting, so we don't
  * hold up the sync while mounting a device. (The newly
  * mounted device won't need syncing.)
@@ -402,12 +412,15 @@ void sync_supers(void)
        spin_lock(&sb_lock);
 restart:
        list_for_each_entry(sb, &super_blocks, s_list) {
-               if (sb->s_dirt) {
+               if (sb->s_op->write_super && sb->s_dirt) {
                        sb->s_count++;
                        spin_unlock(&sb_lock);
+
                        down_read(&sb->s_umount);
-                       write_super(sb);
+                       if (sb->s_root && sb->s_dirt)
+                               sb->s_op->write_super(sb);
                        up_read(&sb->s_umount);
+
                        spin_lock(&sb_lock);
                        if (__put_super_and_need_restart(sb))
                                goto restart;
@@ -416,59 +429,6 @@ restart:
        spin_unlock(&sb_lock);
 }
 
-/*
- * Call the ->sync_fs super_op against all filesytems which are r/w and
- * which implement it.
- *
- * This operation is careful to avoid the livelock which could easily happen
- * if two or more filesystems are being continuously dirtied.  s_need_sync_fs
- * is used only here.  We set it against all filesystems and then clear it as
- * we sync them.  So redirtied filesystems are skipped.
- *
- * But if process A is currently running sync_filesytems and then process B
- * calls sync_filesystems as well, process B will set all the s_need_sync_fs
- * flags again, which will cause process A to resync everything.  Fix that with
- * a local mutex.
- *
- * (Fabian) Avoid sync_fs with clean fs & wait mode 0
- */
-void sync_filesystems(int wait)
-{
-       struct super_block *sb;
-       static DEFINE_MUTEX(mutex);
-
-       mutex_lock(&mutex);             /* Could be down_interruptible */
-       spin_lock(&sb_lock);
-       list_for_each_entry(sb, &super_blocks, s_list) {
-               if (!sb->s_op->sync_fs)
-                       continue;
-               if (sb->s_flags & MS_RDONLY)
-                       continue;
-               sb->s_need_sync_fs = 1;
-       }
-
-restart:
-       list_for_each_entry(sb, &super_blocks, s_list) {
-               if (!sb->s_need_sync_fs)
-                       continue;
-               sb->s_need_sync_fs = 0;
-               if (sb->s_flags & MS_RDONLY)
-                       continue;       /* hm.  Was remounted r/o meanwhile */
-               sb->s_count++;
-               spin_unlock(&sb_lock);
-               down_read(&sb->s_umount);
-               if (sb->s_root && (wait || sb->s_dirt))
-                       sb->s_op->sync_fs(sb, wait);
-               up_read(&sb->s_umount);
-               /* restart only when sb is no longer on the list */
-               spin_lock(&sb_lock);
-               if (__put_super_and_need_restart(sb))
-                       goto restart;
-       }
-       spin_unlock(&sb_lock);
-       mutex_unlock(&mutex);
-}
-
 /**
  *     get_super - get the superblock of a device
  *     @bdev: device to get the superblock for
@@ -505,6 +465,48 @@ rescan:
 }
 
 EXPORT_SYMBOL(get_super);
+
+/**
+ * get_active_super - get an active reference to the superblock of a device
+ * @bdev: device to get the superblock for
+ *
+ * Scans the superblock list and finds the superblock of the file system
+ * mounted on the device given.  Returns the superblock with an active
+ * reference and s_umount held exclusively or %NULL if none was found.
+ */
+struct super_block *get_active_super(struct block_device *bdev)
+{
+       struct super_block *sb;
+
+       if (!bdev)
+               return NULL;
+
+       spin_lock(&sb_lock);
+       list_for_each_entry(sb, &super_blocks, s_list) {
+               if (sb->s_bdev != bdev)
+                       continue;
+
+               sb->s_count++;
+               spin_unlock(&sb_lock);
+               down_write(&sb->s_umount);
+               if (sb->s_root) {
+                       spin_lock(&sb_lock);
+                       if (sb->s_count > S_BIAS) {
+                               atomic_inc(&sb->s_active);
+                               sb->s_count--;
+                               spin_unlock(&sb_lock);
+                               return sb;
+                       }
+                       spin_unlock(&sb_lock);
+               }
+               up_write(&sb->s_umount);
+               put_super(sb);
+               yield();
+               spin_lock(&sb_lock);
+       }
+       spin_unlock(&sb_lock);
+       return NULL;
+}
  
 struct super_block * user_get_super(dev_t dev)
 {
@@ -530,7 +532,7 @@ rescan:
        return NULL;
 }
 
-asmlinkage long sys_ustat(unsigned dev, struct ustat __user * ubuf)
+SYSCALL_DEFINE2(ustat, unsigned, dev, struct ustat __user *, ubuf)
 {
         struct super_block *s;
         struct ustat tmp;
@@ -555,26 +557,6 @@ out:
 }
 
 /**
- *     mark_files_ro
- *     @sb: superblock in question
- *
- *     All files are marked read/only.  We don't care about pending
- *     delete files so this should be used in 'force' mode only
- */
-
-static void mark_files_ro(struct super_block *sb)
-{
-       struct file *f;
-
-       file_list_lock();
-       list_for_each_entry(f, &sb->s_files, f_u.fu_list) {
-               if (S_ISREG(f->f_path.dentry->d_inode->i_mode) && file_count(f))
-                       f->f_mode &= ~FMODE_WRITE;
-       }
-       file_list_unlock();
-}
-
-/**
  *     do_remount_sb - asks filesystem to change mount options.
  *     @sb:    superblock in question
  *     @flags: numeric part of options
@@ -586,37 +568,58 @@ static void mark_files_ro(struct super_block *sb)
 int do_remount_sb(struct super_block *sb, int flags, void *data, int force)
 {
        int retval;
-       
+       int remount_rw, remount_ro;
+
+       if (sb->s_frozen != SB_UNFROZEN)
+               return -EBUSY;
+
 #ifdef CONFIG_BLOCK
        if (!(flags & MS_RDONLY) && bdev_read_only(sb->s_bdev))
                return -EACCES;
 #endif
+
        if (flags & MS_RDONLY)
                acct_auto_close(sb);
        shrink_dcache_sb(sb);
-       fsync_super(sb);
+       sync_filesystem(sb);
+
+       remount_ro = (flags & MS_RDONLY) && !(sb->s_flags & MS_RDONLY);
+       remount_rw = !(flags & MS_RDONLY) && (sb->s_flags & MS_RDONLY);
 
        /* If we are remounting RDONLY and current sb is read/write,
           make sure there are no rw files opened */
-       if ((flags & MS_RDONLY) && !(sb->s_flags & MS_RDONLY)) {
+       if (remount_ro) {
                if (force)
                        mark_files_ro(sb);
                else if (!fs_may_remount_ro(sb))
                        return -EBUSY;
+               retval = vfs_dq_off(sb, 1);
+               if (retval < 0 && retval != -ENOSYS)
+                       return -EBUSY;
        }
 
        if (sb->s_op->remount_fs) {
-               lock_super(sb);
                retval = sb->s_op->remount_fs(sb, &flags, data);
-               unlock_super(sb);
                if (retval)
                        return retval;
        }
        sb->s_flags = (sb->s_flags & ~MS_RMT_MASK) | (flags & MS_RMT_MASK);
+       if (remount_rw)
+               vfs_dq_quota_on_remount(sb);
+       /*
+        * Some filesystems modify their metadata via some other path than the
+        * bdev buffer cache (eg. use a private mapping, or directories in
+        * pagecache, etc). Also file data modifications go via their own
+        * mappings. So If we try to mount readonly then copy the filesystem
+        * from bdev, we could get stale data, so invalidate it to give a best
+        * effort at coherency.
+        */
+       if (remount_ro && sb->s_bdev)
+               invalidate_bdev(sb->s_bdev);
        return 0;
 }
 
-static void do_emergency_remount(unsigned long foo)
+static void do_emergency_remount(struct work_struct *work)
 {
        struct super_block *sb;
 
@@ -624,27 +627,33 @@ static void do_emergency_remount(unsigned long foo)
        list_for_each_entry(sb, &super_blocks, s_list) {
                sb->s_count++;
                spin_unlock(&sb_lock);
-               down_read(&sb->s_umount);
+               down_write(&sb->s_umount);
                if (sb->s_root && sb->s_bdev && !(sb->s_flags & MS_RDONLY)) {
                        /*
                         * ->remount_fs needs lock_kernel().
                         *
                         * What lock protects sb->s_flags??
                         */
-                       lock_kernel();
                        do_remount_sb(sb, MS_RDONLY, NULL, 1);
-                       unlock_kernel();
                }
-               drop_super(sb);
+               up_write(&sb->s_umount);
+               put_super(sb);
                spin_lock(&sb_lock);
        }
        spin_unlock(&sb_lock);
+       kfree(work);
        printk("Emergency Remount complete\n");
 }
 
 void emergency_remount(void)
 {
-       pdflush_operation(do_emergency_remount, 0);
+       struct work_struct *work;
+
+       work = kmalloc(sizeof(*work), GFP_ATOMIC);
+       if (work) {
+               INIT_WORK(work, do_emergency_remount);
+               schedule_work(work);
+       }
 }
 
 /*
@@ -652,8 +661,9 @@ void emergency_remount(void)
  * filesystems which don't use real block-devices.  -- jrs
  */
 
-static struct idr unnamed_dev_idr;
+static DEFINE_IDA(unnamed_dev_ida);
 static DEFINE_SPINLOCK(unnamed_dev_lock);/* protects the above */
+static int unnamed_dev_start = 0; /* don't bother trying below it */
 
 int set_anon_super(struct super_block *s, void *data)
 {
@@ -661,10 +671,12 @@ int set_anon_super(struct super_block *s, void *data)
        int error;
 
  retry:
-       if (idr_pre_get(&unnamed_dev_idr, GFP_ATOMIC) == 0)
+       if (ida_pre_get(&unnamed_dev_ida, GFP_ATOMIC) == 0)
                return -ENOMEM;
        spin_lock(&unnamed_dev_lock);
-       error = idr_get_new(&unnamed_dev_idr, NULL, &dev);
+       error = ida_get_new_above(&unnamed_dev_ida, unnamed_dev_start, &dev);
+       if (!error)
+               unnamed_dev_start = dev + 1;
        spin_unlock(&unnamed_dev_lock);
        if (error == -EAGAIN)
                /* We raced and lost with another CPU. */
@@ -674,7 +686,9 @@ int set_anon_super(struct super_block *s, void *data)
 
        if ((dev & MAX_ID_MASK) == (1 << MINORBITS)) {
                spin_lock(&unnamed_dev_lock);
-               idr_remove(&unnamed_dev_idr, dev);
+               ida_remove(&unnamed_dev_ida, dev);
+               if (unnamed_dev_start > dev)
+                       unnamed_dev_start = dev;
                spin_unlock(&unnamed_dev_lock);
                return -EMFILE;
        }
@@ -690,17 +704,14 @@ void kill_anon_super(struct super_block *sb)
 
        generic_shutdown_super(sb);
        spin_lock(&unnamed_dev_lock);
-       idr_remove(&unnamed_dev_idr, slot);
+       ida_remove(&unnamed_dev_ida, slot);
+       if (slot < unnamed_dev_start)
+               unnamed_dev_start = slot;
        spin_unlock(&unnamed_dev_lock);
 }
 
 EXPORT_SYMBOL(kill_anon_super);
 
-void __init unnamed_dev_init(void)
-{
-       idr_init(&unnamed_dev_idr);
-}
-
 void kill_litter_super(struct super_block *sb)
 {
        if (sb->s_root)
@@ -710,11 +721,56 @@ void kill_litter_super(struct super_block *sb)
 
 EXPORT_SYMBOL(kill_litter_super);
 
+static int ns_test_super(struct super_block *sb, void *data)
+{
+       return sb->s_fs_info == data;
+}
+
+static int ns_set_super(struct super_block *sb, void *data)
+{
+       sb->s_fs_info = data;
+       return set_anon_super(sb, NULL);
+}
+
+int get_sb_ns(struct file_system_type *fs_type, int flags, void *data,
+       int (*fill_super)(struct super_block *, void *, int),
+       struct vfsmount *mnt)
+{
+       struct super_block *sb;
+
+       sb = sget(fs_type, ns_test_super, ns_set_super, data);
+       if (IS_ERR(sb))
+               return PTR_ERR(sb);
+
+       if (!sb->s_root) {
+               int err;
+               sb->s_flags = flags;
+               err = fill_super(sb, data, flags & MS_SILENT ? 1 : 0);
+               if (err) {
+                       deactivate_locked_super(sb);
+                       return err;
+               }
+
+               sb->s_flags |= MS_ACTIVE;
+       }
+
+       simple_set_mnt(mnt, sb);
+       return 0;
+}
+
+EXPORT_SYMBOL(get_sb_ns);
+
 #ifdef CONFIG_BLOCK
 static int set_bdev_super(struct super_block *s, void *data)
 {
        s->s_bdev = data;
        s->s_dev = s->s_bdev->bd_dev;
+
+       /*
+        * We set the bdi here to the queue backing, file systems can
+        * overwrite this in ->fill_super()
+        */
+       s->s_bdi = &bdev_get_queue(s->s_bdev)->backing_dev_info;
        return 0;
 }
 
@@ -730,9 +786,13 @@ int get_sb_bdev(struct file_system_type *fs_type,
 {
        struct block_device *bdev;
        struct super_block *s;
+       fmode_t mode = FMODE_READ;
        int error = 0;
 
-       bdev = open_bdev_excl(dev_name, flags, fs_type);
+       if (!(flags & MS_RDONLY))
+               mode |= FMODE_WRITE;
+
+       bdev = open_bdev_exclusive(dev_name, mode, fs_type);
        if (IS_ERR(bdev))
                return PTR_ERR(bdev);
 
@@ -741,43 +801,49 @@ int get_sb_bdev(struct file_system_type *fs_type,
         * will protect the lockfs code from trying to start a snapshot
         * while we are mounting
         */
-       down(&bdev->bd_mount_sem);
+       mutex_lock(&bdev->bd_fsfreeze_mutex);
+       if (bdev->bd_fsfreeze_count > 0) {
+               mutex_unlock(&bdev->bd_fsfreeze_mutex);
+               error = -EBUSY;
+               goto error_bdev;
+       }
        s = sget(fs_type, test_bdev_super, set_bdev_super, bdev);
-       up(&bdev->bd_mount_sem);
+       mutex_unlock(&bdev->bd_fsfreeze_mutex);
        if (IS_ERR(s))
                goto error_s;
 
        if (s->s_root) {
                if ((flags ^ s->s_flags) & MS_RDONLY) {
-                       up_write(&s->s_umount);
-                       deactivate_super(s);
+                       deactivate_locked_super(s);
                        error = -EBUSY;
                        goto error_bdev;
                }
 
-               close_bdev_excl(bdev);
+               close_bdev_exclusive(bdev, mode);
        } else {
                char b[BDEVNAME_SIZE];
 
                s->s_flags = flags;
+               s->s_mode = mode;
                strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id));
                sb_set_blocksize(s, block_size(bdev));
                error = fill_super(s, data, flags & MS_SILENT ? 1 : 0);
                if (error) {
-                       up_write(&s->s_umount);
-                       deactivate_super(s);
+                       deactivate_locked_super(s);
                        goto error;
                }
 
                s->s_flags |= MS_ACTIVE;
+               bdev->bd_super = s;
        }
 
-       return simple_set_mnt(mnt, s);
+       simple_set_mnt(mnt, s);
+       return 0;
 
 error_s:
        error = PTR_ERR(s);
 error_bdev:
-       close_bdev_excl(bdev);
+       close_bdev_exclusive(bdev, mode);
 error:
        return error;
 }
@@ -787,10 +853,12 @@ EXPORT_SYMBOL(get_sb_bdev);
 void kill_block_super(struct super_block *sb)
 {
        struct block_device *bdev = sb->s_bdev;
+       fmode_t mode = sb->s_mode;
 
+       bdev->bd_super = NULL;
        generic_shutdown_super(sb);
        sync_blockdev(bdev);
-       close_bdev_excl(bdev);
+       close_bdev_exclusive(bdev, mode);
 }
 
 EXPORT_SYMBOL(kill_block_super);
@@ -811,12 +879,12 @@ int get_sb_nodev(struct file_system_type *fs_type,
 
        error = fill_super(s, data, flags & MS_SILENT ? 1 : 0);
        if (error) {
-               up_write(&s->s_umount);
-               deactivate_super(s);
+               deactivate_locked_super(s);
                return error;
        }
        s->s_flags |= MS_ACTIVE;
-       return simple_set_mnt(mnt, s);
+       simple_set_mnt(mnt, s);
+       return 0;
 }
 
 EXPORT_SYMBOL(get_sb_nodev);
@@ -841,14 +909,15 @@ int get_sb_single(struct file_system_type *fs_type,
                s->s_flags = flags;
                error = fill_super(s, data, flags & MS_SILENT ? 1 : 0);
                if (error) {
-                       up_write(&s->s_umount);
-                       deactivate_super(s);
+                       deactivate_locked_super(s);
                        return error;
                }
                s->s_flags |= MS_ACTIVE;
+       } else {
+               do_remount_sb(s, flags, data, 0);
        }
-       do_remount_sb(s, flags, data, 0);
-       return simple_set_mnt(mnt, s);
+       simple_set_mnt(mnt, s);
+       return 0;
 }
 
 EXPORT_SYMBOL(get_sb_single);
@@ -868,12 +937,15 @@ vfs_kern_mount(struct file_system_type *type, int flags, const char *name, void
        if (!mnt)
                goto out;
 
-       if (data) {
+       if (flags & MS_KERNMOUNT)
+               mnt->mnt_flags = MNT_INTERNAL;
+
+       if (data && !(type->fs_flags & FS_BINARY_MOUNTDATA)) {
                secdata = alloc_secdata();
                if (!secdata)
                        goto out_mnt;
 
-               error = security_sb_copy_data(type, data, secdata);
+               error = security_sb_copy_data(data, secdata);
                if (error)
                        goto out_free_secdata;
        }
@@ -883,10 +955,20 @@ vfs_kern_mount(struct file_system_type *type, int flags, const char *name, void
                goto out_free_secdata;
        BUG_ON(!mnt->mnt_sb);
 
-       error = security_sb_kern_mount(mnt->mnt_sb, secdata);
+       error = security_sb_kern_mount(mnt->mnt_sb, flags, secdata);
        if (error)
                goto out_sb;
 
+       /*
+        * filesystems should never set s_maxbytes larger than MAX_LFS_FILESIZE
+        * but s_maxbytes was an unsigned long long for many releases. Throw
+        * this warning for a little while to try and catch filesystems that
+        * violate this rule. This warning should be either removed or
+        * converted to a BUG() in 2.6.34.
+        */
+       WARN((mnt->mnt_sb->s_maxbytes < 0), "%s set sb->s_maxbytes to "
+               "negative value (%lld)\n", type->name, mnt->mnt_sb->s_maxbytes);
+
        mnt->mnt_mountpoint = mnt->mnt_root;
        mnt->mnt_parent = mnt;
        up_write(&mnt->mnt_sb->s_umount);
@@ -894,8 +976,7 @@ vfs_kern_mount(struct file_system_type *type, int flags, const char *name, void
        return mnt;
 out_sb:
        dput(mnt->mnt_root);
-       up_write(&mnt->mnt_sb->s_umount);
-       deactivate_super(mnt->mnt_sb);
+       deactivate_locked_super(mnt->mnt_sb);
 out_free_secdata:
        free_secdata(secdata);
 out_mnt:
@@ -943,6 +1024,7 @@ do_kern_mount(const char *fstype, int flags, const char *name, void *data)
        put_filesystem(type);
        return mnt;
 }
+EXPORT_SYMBOL_GPL(do_kern_mount);
 
 struct vfsmount *kern_mount_data(struct file_system_type *type, void *data)
 {