1 files changed, 49 insertions, 34 deletions

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 045f98854f14..bc8f27cc4483 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -17,11 +17,13 @@
 #include <linux/module.h>
 #include <linux/blkpg.h>
 #include <linux/buffer_head.h>
+#include <linux/writeback.h>
 #include <linux/mpage.h>
 #include <linux/mount.h>
 #include <linux/uio.h>
 #include <linux/namei.h>
 #include <asm/uaccess.h>
+#include "internal.h"
 
 struct bdev_inode {
         struct block_device bdev;
@@ -543,11 +545,11 @@ static struct kobject *bdev_get_holder(struct block_device *bdev)
                 return kobject_get(bdev->bd_disk->holder_dir);
 }
 
-static void add_symlink(struct kobject *from, struct kobject *to)
+static int add_symlink(struct kobject *from, struct kobject *to)
 {
         if (!from || !to)
-                return;
-        sysfs_create_link(from, to, kobject_name(to));
+                return 0;
+        return sysfs_create_link(from, to, kobject_name(to));
 }
 
 static void del_symlink(struct kobject *from, struct kobject *to)
@@ -648,30 +650,38 @@ static void free_bd_holder(struct bd_holder *bo)
  * If there is no matching entry with @bo in @bdev->bd_holder_list,
  * add @bo to the list, create symlinks.
  *
- * Returns 1 if @bo was added to the list.
- * Returns 0 if @bo wasn't used by any reason and should be freed.
+ * Returns 0 if symlinks are created or already there.
+ * Returns -ve if something fails and @bo can be freed.
  */
 static int add_bd_holder(struct block_device *bdev, struct bd_holder *bo)
 {
         struct bd_holder *tmp;
+        int ret;
 
         if (!bo)
-                return 0;
+                return -EINVAL;
 
         list_for_each_entry(tmp, &bdev->bd_holder_list, list) {
                 if (tmp->sdir == bo->sdir) {
                         tmp->count++;
+                        /* We've already done what we need to do here. */
+                        free_bd_holder(bo);
                         return 0;
                 }
         }
 
         if (!bd_holder_grab_dirs(bdev, bo))
-                return 0;
+                return -EBUSY;
 
-        add_symlink(bo->sdir, bo->sdev);
-        add_symlink(bo->hdir, bo->hdev);
-        list_add_tail(&bo->list, &bdev->bd_holder_list);
-        return 1;
+        ret = add_symlink(bo->sdir, bo->sdev);
+        if (ret == 0) {
+                ret = add_symlink(bo->hdir, bo->hdev);
+                if (ret)
+                        del_symlink(bo->sdir, bo->sdev);
+        }
+        if (ret == 0)
+                list_add_tail(&bo->list, &bdev->bd_holder_list);
+        return ret;
 }
 
 /**
@@ -741,7 +751,9 @@ static int bd_claim_by_kobject(struct block_device *bdev, void *holder,
 
         mutex_lock_nested(&bdev->bd_mutex, BD_MUTEX_PARTITION);
         res = bd_claim(bdev, holder);
-        if (res || !add_bd_holder(bdev, bo))
+        if (res == 0)
+                res = add_bd_holder(bdev, bo);
+        if (res)
                 free_bd_holder(bo);
         mutex_unlock(&bdev->bd_mutex);
 
@@ -1021,7 +1033,7 @@ do_open(struct block_device *bdev, struct file *file, unsigned int subclass)
                                 rescan_partitions(bdev->bd_disk, bdev);
                 } else {
                         mutex_lock_nested(&bdev->bd_contains->bd_mutex,
-                                          BD_MUTEX_PARTITION);
+                                          BD_MUTEX_WHOLE);
                         bdev->bd_contains->bd_part_count++;
                         mutex_unlock(&bdev->bd_contains->bd_mutex);
                 }
@@ -1142,22 +1154,6 @@ static int blkdev_close(struct inode * inode, struct file * filp)
         return blkdev_put(bdev);
 }
 
-static ssize_t blkdev_file_write(struct file *file, const char __user *buf,
-                                   size_t count, loff_t *ppos)
-{
-        struct iovec local_iov = { .iov_base = (void __user *)buf, .iov_len = count };
-
-        return generic_file_write_nolock(file, &local_iov, 1, ppos);
-}
-
-static ssize_t blkdev_file_aio_write(struct kiocb *iocb, const char __user *buf,
-                                   size_t count, loff_t pos)
-{
-        struct iovec local_iov = { .iov_base = (void __user *)buf, .iov_len = count };
-
-        return generic_file_aio_write_nolock(iocb, &local_iov, 1, &iocb->ki_pos);
-}
-
 static long block_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 {
         return blkdev_ioctl(file->f_mapping->host, file, cmd, arg);
@@ -1177,18 +1173,16 @@ const struct file_operations def_blk_fops = {
         .open           = blkdev_open,
         .release        = blkdev_close,
         .llseek         = block_llseek,
-        .read           = generic_file_read,
-        .write          = blkdev_file_write,
+        .read           = do_sync_read,
+        .write          = do_sync_write,
         .aio_read       = generic_file_aio_read,
-        .aio_write      = blkdev_file_aio_write, 
+        .aio_write      = generic_file_aio_write_nolock,
         .mmap           = generic_file_mmap,
         .fsync          = block_fsync,
         .unlocked_ioctl = block_ioctl,
 #ifdef CONFIG_COMPAT
         .compat_ioctl   = compat_blkdev_ioctl,
 #endif
-        .readv          = generic_file_readv,
-        .writev         = generic_file_write_nolock,
         .sendfile       = generic_file_sendfile,
         .splice_read    = generic_file_splice_read,
         .splice_write   = generic_file_splice_write,
@@ -1303,3 +1297,24 @@ void close_bdev_excl(struct block_device *bdev)
 }
 
 EXPORT_SYMBOL(close_bdev_excl);
+
+int __invalidate_device(struct block_device *bdev)
+{
+        struct super_block *sb = get_super(bdev);
+        int res = 0;
+
+        if (sb) {
+                /*
+                 * no need to lock the super, get_super holds the
+                 * read mutex so the filesystem cannot go away
+                 * under us (->put_super runs with the write lock
+                 * hold).
+                 */
+                shrink_dcache_sb(sb);
+                res = invalidate_inodes(sb);
+                drop_super(sb);
+        }
+        invalidate_bdev(bdev, 0);
+        return res;
+}
+EXPORT_SYMBOL(__invalidate_device);