1 files changed, 123 insertions, 59 deletions

diff --git a/fs/block_dev.c b/fs/block_dev.c
index aff54219e049..d84f0469a016 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -540,22 +540,6 @@ EXPORT_SYMBOL(bd_release);
  *           /sys/block/sda/holders/dm-0 --> /sys/block/dm-0
  */
 
-static struct kobject *bdev_get_kobj(struct block_device *bdev)
-{
-        if (bdev->bd_contains != bdev)
-                return kobject_get(&bdev->bd_part->dev.kobj);
-        else
-                return kobject_get(&bdev->bd_disk->dev.kobj);
-}
-
-static struct kobject *bdev_get_holder(struct block_device *bdev)
-{
-        if (bdev->bd_contains != bdev)
-                return kobject_get(bdev->bd_part->holder_dir);
-        else
-                return kobject_get(bdev->bd_disk->holder_dir);
-}
-
 static int add_symlink(struct kobject *from, struct kobject *to)
 {
         if (!from || !to)
@@ -604,11 +588,11 @@ static int bd_holder_grab_dirs(struct block_device *bdev,
         if (!bo->hdev)
                 goto fail_put_sdir;
 
-        bo->sdev = bdev_get_kobj(bdev);
+        bo->sdev = kobject_get(&part_to_dev(bdev->bd_part)->kobj);
         if (!bo->sdev)
                 goto fail_put_hdev;
 
-        bo->hdir = bdev_get_holder(bdev);
+        bo->hdir = kobject_get(bdev->bd_part->holder_dir);
         if (!bo->hdir)
                 goto fail_put_sdev;
 
@@ -868,6 +852,87 @@ struct block_device *open_by_devnum(dev_t dev, unsigned mode)
 
 EXPORT_SYMBOL(open_by_devnum);
 
+/**
+ * flush_disk - invalidates all buffer-cache entries on a disk
+ *
+ * @bdev:      struct block device to be flushed
+ *
+ * Invalidates all buffer-cache entries on a disk. It should be called
+ * when a disk has been changed -- either by a media change or online
+ * resize.
+ */
+static void flush_disk(struct block_device *bdev)
+{
+        if (__invalidate_device(bdev)) {
+                char name[BDEVNAME_SIZE] = "";
+
+                if (bdev->bd_disk)
+                        disk_name(bdev->bd_disk, 0, name);
+                printk(KERN_WARNING "VFS: busy inodes on changed media or "
+                       "resized disk %s\n", name);
+        }
+
+        if (!bdev->bd_disk)
+                return;
+        if (disk_partitionable(bdev->bd_disk))
+                bdev->bd_invalidated = 1;
+}
+
+/**
+ * check_disk_size_change - checks for disk size change and adjusts bdev size.
+ * @disk: struct gendisk to check
+ * @bdev: struct bdev to adjust.
+ *
+ * This routine checks to see if the bdev size does not match the disk size
+ * and adjusts it if it differs.
+ */
+void check_disk_size_change(struct gendisk *disk, struct block_device *bdev)
+{
+        loff_t disk_size, bdev_size;
+
+        disk_size = (loff_t)get_capacity(disk) << 9;
+        bdev_size = i_size_read(bdev->bd_inode);
+        if (disk_size != bdev_size) {
+                char name[BDEVNAME_SIZE];
+
+                disk_name(disk, 0, name);
+                printk(KERN_INFO
+                       "%s: detected capacity change from %lld to %lld\n",
+                       name, bdev_size, disk_size);
+                i_size_write(bdev->bd_inode, disk_size);
+                flush_disk(bdev);
+        }
+}
+EXPORT_SYMBOL(check_disk_size_change);
+
+/**
+ * revalidate_disk - wrapper for lower-level driver's revalidate_disk call-back
+ * @disk: struct gendisk to be revalidated
+ *
+ * This routine is a wrapper for lower-level driver's revalidate_disk
+ * call-backs.  It is used to do common pre and post operations needed
+ * for all revalidate_disk operations.
+ */
+int revalidate_disk(struct gendisk *disk)
+{
+        struct block_device *bdev;
+        int ret = 0;
+
+        if (disk->fops->revalidate_disk)
+                ret = disk->fops->revalidate_disk(disk);
+
+        bdev = bdget_disk(disk, 0);
+        if (!bdev)
+                return ret;
+
+        mutex_lock(&bdev->bd_mutex);
+        check_disk_size_change(disk, bdev);
+        mutex_unlock(&bdev->bd_mutex);
+        bdput(bdev);
+        return ret;
+}
+EXPORT_SYMBOL(revalidate_disk);
+
 /*
  * This routine checks whether a removable media has been changed,
  * and invalidates all buffer-cache-entries in that case. This
@@ -887,13 +952,9 @@ int check_disk_change(struct block_device *bdev)
         if (!bdops->media_changed(bdev->bd_disk))
                 return 0;
 
-        if (__invalidate_device(bdev))
-                printk("VFS: busy inodes on changed media.\n");
-
+        flush_disk(bdev);
         if (bdops->revalidate_disk)
                 bdops->revalidate_disk(bdev->bd_disk);
-        if (bdev->bd_disk->minors > 1)
-                bdev->bd_invalidated = 1;
         return 1;
 }
 
@@ -927,10 +988,10 @@ static int __blkdev_put(struct block_device *bdev, int for_part);
 
 static int do_open(struct block_device *bdev, struct file *file, int for_part)
 {
-        struct module *owner = NULL;
         struct gendisk *disk;
+        struct hd_struct *part = NULL;
         int ret;
-        int part;
+        int partno;
         int perm = 0;
 
         if (file->f_mode & FMODE_READ)
@@ -948,25 +1009,27 @@ static int do_open(struct block_device *bdev, struct file *file, int for_part)
 
         ret = -ENXIO;
         file->f_mapping = bdev->bd_inode->i_mapping;
+
         lock_kernel();
-        disk = get_gendisk(bdev->bd_dev, &part);
-        if (!disk) {
-                unlock_kernel();
-                bdput(bdev);
-                return ret;
-        }
-        owner = disk->fops->owner;
+
+        disk = get_gendisk(bdev->bd_dev, &partno);
+        if (!disk)
+                goto out_unlock_kernel;
+        part = disk_get_part(disk, partno);
+        if (!part)
+                goto out_unlock_kernel;
 
         mutex_lock_nested(&bdev->bd_mutex, for_part);
         if (!bdev->bd_openers) {
                 bdev->bd_disk = disk;
+                bdev->bd_part = part;
                 bdev->bd_contains = bdev;
-                if (!part) {
+                if (!partno) {
                         struct backing_dev_info *bdi;
                         if (disk->fops->open) {
                                 ret = disk->fops->open(bdev->bd_inode, file);
                                 if (ret)
-                                        goto out_first;
+                                        goto out_clear;
                         }
                         if (!bdev->bd_openers) {
                                 bd_set_size(bdev,(loff_t)get_capacity(disk)<<9);
@@ -978,36 +1041,36 @@ static int do_open(struct block_device *bdev, struct file *file, int for_part)
                         if (bdev->bd_invalidated)
                                 rescan_partitions(disk, bdev);
                 } else {
-                        struct hd_struct *p;
                         struct block_device *whole;
                         whole = bdget_disk(disk, 0);
                         ret = -ENOMEM;
                         if (!whole)
-                                goto out_first;
+                                goto out_clear;
                         BUG_ON(for_part);
                         ret = __blkdev_get(whole, file->f_mode, file->f_flags, 1);
                         if (ret)
-                                goto out_first;
+                                goto out_clear;
                         bdev->bd_contains = whole;
-                        p = disk->part[part - 1];
                         bdev->bd_inode->i_data.backing_dev_info =
                            whole->bd_inode->i_data.backing_dev_info;
-                        if (!(disk->flags & GENHD_FL_UP) || !p || !p->nr_sects) {
+                        if (!(disk->flags & GENHD_FL_UP) ||
+                            !part || !part->nr_sects) {
                                 ret = -ENXIO;
-                                goto out_first;
+                                goto out_clear;
                         }
-                        kobject_get(&p->dev.kobj);
-                        bdev->bd_part = p;
-                        bd_set_size(bdev, (loff_t) p->nr_sects << 9);
+                        bd_set_size(bdev, (loff_t)part->nr_sects << 9);
                 }
         } else {
+                disk_put_part(part);
                 put_disk(disk);
-                module_put(owner);
+                module_put(disk->fops->owner);
+                part = NULL;
+                disk = NULL;
                 if (bdev->bd_contains == bdev) {
                         if (bdev->bd_disk->fops->open) {
                                 ret = bdev->bd_disk->fops->open(bdev->bd_inode, file);
                                 if (ret)
-                                        goto out;
+                                        goto out_unlock_bdev;
                         }
                         if (bdev->bd_invalidated)
                                 rescan_partitions(bdev->bd_disk, bdev);
@@ -1020,19 +1083,24 @@ static int do_open(struct block_device *bdev, struct file *file, int for_part)
         unlock_kernel();
         return 0;
 
-out_first:
+ out_clear:
         bdev->bd_disk = NULL;
+        bdev->bd_part = NULL;
         bdev->bd_inode->i_data.backing_dev_info = &default_backing_dev_info;
         if (bdev != bdev->bd_contains)
                 __blkdev_put(bdev->bd_contains, 1);
         bdev->bd_contains = NULL;
-        put_disk(disk);
-        module_put(owner);
-out:
+ out_unlock_bdev:
         mutex_unlock(&bdev->bd_mutex);
+ out_unlock_kernel:
         unlock_kernel();
-        if (ret)
-                bdput(bdev);
+
+        disk_put_part(part);
+        if (disk)
+                module_put(disk->fops->owner);
+        put_disk(disk);
+        bdput(bdev);
+
         return ret;
 }
 
@@ -1117,11 +1185,8 @@ static int __blkdev_put(struct block_device *bdev, int for_part)
 
                 put_disk(disk);
                 module_put(owner);
-
-                if (bdev->bd_contains != bdev) {
-                        kobject_put(&bdev->bd_part->dev.kobj);
-                        bdev->bd_part = NULL;
-                }
+                disk_put_part(bdev->bd_part);
+                bdev->bd_part = NULL;
                 bdev->bd_disk = NULL;
                 bdev->bd_inode->i_data.backing_dev_info = &default_backing_dev_info;
                 if (bdev != bdev->bd_contains)
@@ -1197,10 +1262,9 @@ EXPORT_SYMBOL(ioctl_by_bdev);
 
 /**
  * lookup_bdev  - lookup a struct block_device by name
+ * @pathname:   special file representing the block device
  *
- * @path:       special file representing the block device
- *
- * Get a reference to the blockdevice at @path in the current
+ * Get a reference to the blockdevice at @pathname in the current
  * namespace if possible and return it.  Return ERR_PTR(error)
  * otherwise.
  */